WO2017221760A1 - Half mirror and mirror with image displaying function - Google Patents

Half mirror and mirror with image displaying function Download PDF

Info

Publication number
WO2017221760A1
WO2017221760A1 PCT/JP2017/021699 JP2017021699W WO2017221760A1 WO 2017221760 A1 WO2017221760 A1 WO 2017221760A1 JP 2017021699 W JP2017021699 W JP 2017021699W WO 2017221760 A1 WO2017221760 A1 WO 2017221760A1
Authority
WO
WIPO (PCT)
Prior art keywords
layer
half mirror
liquid crystal
image display
retardation film
Prior art date
Application number
PCT/JP2017/021699
Other languages
French (fr)
Japanese (ja)
Inventor
広敏 安藤
田口　貴雄
美喜男 都丸
Original Assignee
富士フイルム株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2017108085A external-priority patent/JP2017227879A/en
Application filed by 富士フイルム株式会社 filed Critical 富士フイルム株式会社
Publication of WO2017221760A1 publication Critical patent/WO2017221760A1/en
Priority to US16/178,939 priority Critical patent/US20190079304A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R1/00—Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
    • B60R1/02—Rear-view mirror arrangements
    • B60R1/04—Rear-view mirror arrangements mounted inside vehicle
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R1/00—Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
    • B60R1/12—Mirror assemblies combined with other articles, e.g. clocks
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/13363—Birefringent elements, e.g. for optical compensation
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
    • G09F9/00—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements

Definitions

  • the present invention relates to a half mirror and a mirror with an image display function including the half mirror.
  • Patent Document 1 describes a mirror with a vehicle image display function that can display an image such as an image captured by a vehicle-mounted camera on a vehicle mirror.
  • a liquid crystal display device is provided inside the housing of the vehicle mirror, and an image is displayed through a half mirror provided on the front surface of the vehicle mirror. The image display on the mirror is realized.
  • Patent Document 2 discloses a mirror with an information display function applied to interior, cosmetic, crime prevention, and safety mirrors, and a polarizing reflector is used as a half mirror. It is described.
  • Patent Document 3 a method in which a reflective film is thermocompression bonded to a resin layer obtained by injection molding is known.
  • An object of the present invention is to provide a half mirror that gives a mirror reflection image without unevenness as a half mirror having a polarizing reflector on a resin layer formed by processing including heating and pressing. Furthermore, the present invention provides a mirror with an image display function including a half mirror having a polarizing reflector on a resin layer formed by processing including heating and pressurization, as well as a non-uniform mirror reflection image, and a bright, non-uniformity. It is an object of the present invention to provide a mirror with an image display function that gives a non-image.
  • the present inventors diligently studied to solve the above problems and completed the present invention.
  • the present invention provides the following [1] to [19].
  • [1] An observation surface, a molded resin layer, and a polarizing reflector are included in this order, Including at least one high Re retardation film between the observation surface and the polarizing reflector, the total front retardation of the high Re retardation film is 3000 nm or more, A half mirror including a first high Re retardation film as the high Re retardation film between the observation surface and the molding resin layer.
  • [3] The half mirror according to [1] or [2], wherein the total front retardation of the high Re retardation film is 5000 nm or more.
  • the half mirror according to [6] wherein the direction of the slow axis of the first high Re retardation film is the same as the direction of the slow axis of the second high Re retardation film.
  • the molded resin layer includes one or more polymers selected from the group consisting of polycarbonate, poly (meth) acrylate, polyester, and cycloolefin polymer.
  • [13] Further includes a quarter wave plate, The half mirror according to any one of [10] to [12], including the molded resin layer, the polarizing reflector, and the quarter-wave plate in this order. [14] The half mirror according to [13], wherein the polarizing reflector and the quarter-wave plate are in direct contact with each other.
  • the image display device emits linearly polarized light to form an image
  • the image display device has a backlight that gives a continuous emission spectrum
  • the mirror with an image display function according to [17] wherein a slow axis of the first high Re retardation film forms an angle of 30 ° to 60 ° with a polarization direction of the linearly polarized light.
  • the mirror with an image display function according to [18] wherein the image display device is a liquid crystal display device, and the backlight is a white LED.
  • a half mirror that gives a mirror reflection image without unevenness as a half mirror having a polarizing reflector on a resin layer formed by processing including heating and pressing.
  • a mirror with an image display function including a half mirror having a polarizing reflector on a resin layer formed by processing including heating and pressurization, a bright and non-uniform image is displayed together with a non-uniform mirror reflection image.
  • a mirror with an image display function can be provided.
  • “selective” for circularly polarized light means that either the right circularly polarized light component or the left circularly polarized light component has more light than the other circularly polarized light component.
  • the degree of circular polarization of light is preferably 0.3 or more, more preferably 0.6 or more, and even more preferably 0.8 or more. It is particularly preferred that it is substantially 1.0. Table In / (I R + I L)
  • sense for circularly polarized light means right circularly polarized light or left circularly polarized light.
  • the sense of circularly polarized light is right-handed circularly polarized light when the electric field vector tip turns clockwise as time increases when viewed as the light travels toward you, and left when it turns counterclockwise. Defined as being circularly polarized.
  • the term “sense” is sometimes used for the twist direction of the spiral of the cholesteric liquid crystal.
  • the twist direction (sense) of the spiral of the cholesteric liquid crystal is right, the right circular polarized light is reflected and the left circular polarized light is transmitted.
  • the spiral sense of the cholesteric liquid crystal is on the left, it reflects left circularly polarized light and transmits right circularly polarized light.
  • the front phase difference is a value measured using an AxoScan manufactured by Axometrics.
  • the measurement wavelength is 550 nm unless otherwise specified.
  • the front phase difference is a value measured by making light in a wavelength range of visible light such as the central wavelength of selective reflection of the cholesteric liquid crystal layer incident in the normal direction of the film in KOBRA 21ADH or WR (manufactured by Oji Scientific Instruments). You can also When selecting the measurement wavelength, the wavelength selection filter can be exchanged manually, or the measurement value can be converted by a program or the like.
  • the front phase difference is sometimes referred to as “Re”.
  • mirror reflection image means an image observed based on reflection from a half mirror. The mirror reflection image only needs to be observed on the observation surface.
  • image refers to an image of an image display device or an image of an image display device that is observed by a mirror with an image display function when the image is displayed on an image display unit of the image display device. It means the image of origin.
  • a half mirror means a mirror having a function of reflecting light and a function of transmitting at least part of light having a desired wavelength.
  • the half mirror of the present invention includes an observation surface, a molded resin layer, and a polarizing reflector in this order, and further includes a high Re retardation film.
  • the half mirror may include other layers such as an optical functional layer, an adhesive layer, and a thermoplastic welding layer.
  • the half mirror of this invention should just use the outermost surface which is a shaping
  • the observation surface is a surface on the side where the mirror reflection image is observed, and means the reflection surface of the half mirror.
  • the shape of a half mirror should just be a thing according to a use, and is not specifically limited, It is preferable that it is plate shape or film shape.
  • the half mirror may have a curved surface. That is, the half mirror may be flat or curved.
  • a curved shape can be designed with a free-form surface such as a polynomial aspherical surface or a Zernike polynomial surface according to the required optical performance other than the spherical surface.
  • a shape in which the observation surface is a convex curved surface is preferable.
  • the molded resin layer means a resin layer molded by processing including heating and pressing.
  • the molded resin layer is preferably obtained by injection molding. The method for producing the molded resin layer will be described later.
  • the shape of the molded resin layer is not particularly limited, and is preferably a plate shape or a film shape.
  • the molded resin layer may have a curved surface. That is, the molded resin layer may be flat or curved.
  • a transparent resin layer in the visible light region is used as the molded resin layer.
  • being transparent in the visible light region means that the light transmittance in the visible light region is 80% or more, preferably 85% or more.
  • the light transmittance used as a scale of transparency is obtained by the method described in JIS A5759. That is, the transmittance obtained at a wavelength of 380 nm to 780 nm is measured with a spectrophotometer, and the weight obtained from the spectral distribution of CIE (International Commission on Illumination) daylight D65, the wavelength distribution of CIE light adaptation standard relative luminous sensitivity, and the wavelength interval.
  • the light transmittance is obtained by multiplying the coefficient and performing a weighted average.
  • the molded resin layer is likely to have non-uniform birefringence due to processing including heating and pressing.
  • the front retardation distribution of the molded resin layer is preferably 50 nm or more, and particularly preferably 100 nm or more.
  • the distribution of the front retardation of the molded resin layer is preferably about 500 nm at the maximum.
  • the distribution of the front phase difference is obtained by measuring the front phase difference of the measurement object divided into nine equal parts and calculating the difference between the maximum value and the minimum value.
  • the thickness of the molded resin layer may be about 100 ⁇ m to 10 mm, preferably 200 ⁇ m to 5.0 mm, more preferably 500 ⁇ m to 4.0 mm, and still more preferably 1.0 mm to 3.0 mm.
  • the material for forming the molded resin layer examples include thermoplastic resins and thermosetting resins.
  • the material for forming the molded resin layer may contain a monomer having a polymerizable group.
  • a thermoplastic resin is preferable.
  • the material for forming the molded resin layer is a resin that is generally used for injection molding because it is, for example, a resin that is injected into a mold in the manufacture of the molded resin layer.
  • the material for forming the molded resin layer is used as a molten resin heated to the melting point or higher when forming the molded resin layer.
  • thermoplastic resin examples include polycarbonate (PC), poly (meth) acrylate, polyester such as polyethylene terephthalate (PET), and cycloolefin polymer (COP).
  • thermosetting resins include phenolic resins, epoxy resins, melamine resins, urea resins, unsaturated polyester resins, diallyl phthalate resins, polyurethane resins, and silicone resins.
  • polycarbonate poly (meth) acrylate, polyester, and cycloolefin polymer are preferable as the material for forming the molded resin layer
  • poly (meth) acrylate or polycarbonate is more preferable
  • polycarbonate is more preferable.
  • thermoplastic resins examples include Iupilon S3000 l (polycarbonate, manufactured by Mitsubishi Engineering Plastics), Novalex 7022-l (polycarbonate, manufactured by Mitsubishi Engineering Plastics), Sumipex MG5 (poly (meth) acrylate, Sumitomo Chemical Co., Ltd.), PETG K2012 (polyethylene terephthalate, Eastman Chemical Co., Ltd.), Zeonex E48R (cycloolefin polymer, Nippon Zeon Co., Ltd.), Panlite L-1250Z100 (Polycarbonate, Teijin Ltd.), DURBIO T744OIR ( Polycarbonate, manufactured by Mitsubishi Chemical Corporation) can be used.
  • linearly polarized reflective layer examples include a linearly polarized light reflecting layer and a circularly polarized light reflecting layer.
  • the linearly polarized light reflecting layer examples include (i) a linearly polarized light reflecting plate having a multilayer structure, (ii) a polarizer in which thin films having different birefringence are laminated, (iii) a wire grid polarizer, (iv) a polarizing prism, (v) Examples include a scattering anisotropic polarizing plate.
  • Examples of the linearly polarized light reflecting plate having a multilayer structure include those obtained by laminating a plurality of dielectric thin films having different refractive indexes. In order to obtain a wavelength selective reflection film, it is preferable to alternately stack a plurality of high-refractive-index dielectric thin films and low-refractive-index dielectric thin films. It may be.
  • the number of laminated layers is preferably 2 to 20 layers, more preferably 2 to 12 layers, still more preferably 4 to 10 layers, and particularly preferably 6 to 8 layers. By making the number of layers 20 or less, it is possible to prevent a decrease in production efficiency due to multilayer deposition.
  • the order of stacking the dielectric thin films is not particularly limited and can be appropriately selected depending on the purpose. For example, when the refractive index of an adjacent film is high, a film having a lower refractive index is first stacked. . Conversely, if the refractive index of the adjacent layer is low, a film having a higher refractive index is first deposited.
  • the standard for the boundary of the refractive index is 1.8. Note that the refractive index level is not absolute, and among the high refractive index materials, there may be a relatively high refractive index and a low refractive index, or these may be used alternately. .
  • Examples of the material for the high refractive index dielectric thin film include Sb 2 O 3 , Sb 2 S 3 , Bi 2 O 3 , CeO 2 , CeF 3 , HfO 2 , La 2 O 3 , Nd 2 O 3 , and Pr 6.
  • O 11 Sc 2 O 3 , SiO, Ta 2 O 5 , TiO 2 , TlCl, Y 2 O 3 , ZnSe, ZnS, ZrO 2 and the like can be mentioned.
  • Bi 2 O 3 , CeO 2 , CeF 3 , HfO 2 , SiO, Ta 2 O 5 , TiO 2 , Y 2 O 3 , ZnSe, ZnS, ZrO 2 are preferable, and SiO, Ta 2 O 5 , TiO 2 , Y 2 O 3 , ZnSe, ZnS and ZrO 2 are particularly preferred.
  • Examples of the material for the low refractive index dielectric thin film include Al 2 O 3 , BiF 3 , CaF 2 , LaF 3 , PbCl 2 , PbF 2 , LiF, MgF 2 , MgO, NdF 3 , SiO 2 , Si 2 O. 3 , NaF, ThO 2 , ThF 4 and the like.
  • Al 2 O 3 , BiF 3 , CaF 2 , MgF 2 , MgO, SiO 2 and Si 2 O 3 are preferable, and Al 2 O 3 , CaF 2 , MgF 2 , MgO, SiO 2 and Si 2 O 3 are preferable.
  • the material of the dielectric thin film is not particularly limited with respect to the atomic ratio, and can be appropriately selected according to the purpose. The atomic ratio can be adjusted by changing the atmospheric gas concentration during film formation.
  • the method for forming the dielectric thin film is not particularly limited and can be appropriately selected depending on the purpose.
  • physical vapor deposition such as ion plating, vacuum deposition such as ion beam, sputtering, etc. (PVD method), chemical vapor deposition method (CVD method) and the like.
  • the vacuum evaporation method and the sputtering method are preferable, and the sputtering method is particularly preferable.
  • a DC sputtering method having a high film formation rate is preferable. In the DC sputtering method, it is preferable to use a material having high conductivity.
  • a method for forming a multilayer film by a sputtering method for example, (1) a one-chamber method for forming a film alternately or sequentially from a plurality of targets in one chamber, and (2) a continuous film formation in a plurality of chambers.
  • a multi-chamber method for example, (1) a one-chamber method for forming a film alternately or sequentially from a plurality of targets in one chamber, and (2) a continuous film formation in a plurality of chambers.
  • the multi-chamber method is particularly preferable from the viewpoint of productivity and the viewpoint of preventing material contamination.
  • the thickness of the dielectric thin film is preferably ⁇ / 16 to ⁇ , more preferably ⁇ / 8 to 3 ⁇ / 4, and more preferably ⁇ / 6 to 3 ⁇ / 8 in the optical wavelength order.
  • the light propagating in the dielectric deposition layer is determined by the product of the thickness of the dielectric thin film and the refractive index of the film with respect to the light due to multiple reflections of part of the light for each dielectric thin film. Only light of a wavelength is selectively transmitted. Further, the central transmission wavelength of the dielectric vapor deposition layer has an angle dependency with respect to the incident light, and the transmission wavelength can be changed by changing the incident light.
  • a polarizer in which thin films having different birefringence are laminated for example, those described in JP-T-9-506837 can be used.
  • a polarizer when processed under conditions selected to obtain a specific refractive index relationship, a polarizer can be formed using a wide variety of materials.
  • one of the first materials has a different refractive index than the second material in the chosen direction.
  • This difference in refractive index can be achieved in a variety of ways, including stretching, extrusion, or coating during or after film formation.
  • Commercially available products can be used as the polarizer in which thin films having different birefringence are laminated. Examples of commercially available products include DBEF (registered trademark) (manufactured by 3M).
  • a wire grid polarizer is a polarizer that transmits one of polarized light and reflects the other by birefringence of a fine metal wire.
  • the wire grid polarizer is a periodic arrangement of metal wires, and is mainly used as a polarizer in the terahertz wave band. In order for the wire grid to function as a polarizer, it is preferable that the wire interval is sufficiently smaller than the wavelength of the incident electromagnetic wave.
  • metal wires are arranged at equal intervals. The polarization component in the polarization direction parallel to the longitudinal direction of the metal wire is reflected by the wire grid polarizer, and the polarization component in the perpendicular polarization direction is transmitted through the wire grid polarizer.
  • wire grid polarizer a commercially available product can be used, and examples of the commercially available product include a wire grid polarizing filter 50 ⁇ 50, NT46-636 manufactured by Edmund Optics.
  • Circularly polarized reflective layer By using the circularly polarized light reflecting layer, incident light from the molding resin layer side can be reflected as circularly polarized light. Moreover, when using a half mirror for a mirror with an image display function, incident light from the image display device can be transmitted as circularly polarized light. Therefore, in a half mirror using a circularly polarized reflection layer and a mirror with an image display function using this half mirror, an image and a mirror reflection image can be observed through polarization sunglasses without depending on the direction. it can.
  • the circularly polarized light reflecting layer examples include a laminated circularly polarized light reflecting layer including a linearly polarized light reflecting plate and a quarter wavelength plate, and a cholesteric circularly polarized light reflecting layer including a cholesteric liquid crystal layer.
  • the linearly polarized light reflecting plate and the quarter wavelength plate are arranged so that the slow axis of the quarter wavelength plate is 45 ° with respect to the polarized light reflecting axis of the linearly polarized light reflecting plate. That's fine.
  • the quarter wave plate and the linearly polarized light reflecting plate may be bonded by, for example, an adhesive layer.
  • the linearly polarized light reflection plate is arranged and used in the laminated circularly polarized light reflection layer so as to be a surface close to the image display device.
  • the polarization reflection axis of the linearly polarized light reflecting plate may be adjusted so as to transmit this linearly polarized light.
  • the thickness of the circularly polarized light reflecting layer including the linearly polarized light reflecting plate and the quarter wavelength plate is preferably in the range of 2.0 ⁇ m to 300 ⁇ m, more preferably in the range of 8.0 ⁇ m to 200 ⁇ m.
  • the linearly polarized light reflecting plate those described above as the linearly polarized light reflecting layer can be used.
  • the quarter wavelength plate a quarter wavelength plate described later can be used.
  • the cholesteric circularly polarized light reflection layer includes at least one cholesteric liquid crystal layer.
  • the cholesteric liquid crystal layer included in the cholesteric circularly polarized light reflection layer may be any layer that exhibits selective reflection in the visible light region.
  • the circularly polarized light reflecting layer may include two or more cholesteric liquid crystal layers, and may include other layers such as an alignment layer.
  • the circularly polarized light reflecting layer is preferably composed only of a cholesteric liquid crystal layer. Further, when the circularly polarized light reflection layer includes a plurality of cholesteric liquid crystal layers, it is preferable that they are in direct contact with adjacent cholesteric liquid crystal layers.
  • the circularly polarized light reflection layer preferably includes three or more cholesteric liquid crystal layers such as three layers and four layers.
  • the thickness of the cholesteric circularly polarized light reflecting layer is preferably in the range of 1.0 ⁇ m to 300 ⁇ m, more preferably in the range of 1.5 ⁇ m to 100 ⁇ m, and still more preferably in the range of 2.0 ⁇ m to 20 ⁇ m.
  • a cholesteric liquid crystal layer means a layer in which a cholesteric liquid crystal phase is fixed.
  • the cholesteric liquid crystal layer is sometimes simply referred to as a liquid crystal layer.
  • the cholesteric liquid crystal phase selectively reflects circularly polarized light of either right circularly polarized light or left circularly polarized light in a specific wavelength region and selectively transmits circularly polarized light of the other sense. It is known to show.
  • the circularly polarized light selective reflection is sometimes simply referred to as selective reflection.
  • films formed from a composition containing a polymerizable liquid crystal compound have been known as films containing a layer in which a cholesteric liquid crystal phase exhibiting circularly polarized light selective reflection is fixed.
  • films containing a layer in which a cholesteric liquid crystal phase exhibiting circularly polarized light selective reflection is fixed are known.
  • those conventional techniques are known. Can be referred to.
  • the cholesteric liquid crystal layer may be a layer that maintains the orientation of the liquid crystal compound that is in the cholesteric liquid crystal phase.
  • a polymerizable liquid crystal compound is brought into an orientation state of a cholesteric liquid crystal phase, and then polymerized and cured by ultraviolet irradiation, heating, etc. to form a non-flowable layer, and simultaneously aligned by an external field or an external force. Any layer may be used as long as the shape is not changed.
  • the cholesteric liquid crystal layer it is sufficient that the optical properties of the cholesteric liquid crystal phase are maintained in the layer, and the liquid crystal compound in the layer may no longer exhibit liquid crystallinity.
  • the polymerizable liquid crystal compound may have a high molecular weight due to a curing reaction and may no longer have liquid crystallinity.
  • the selective reflection center wavelength and the half width of the cholesteric liquid crystal layer can be obtained as follows. When the transmission spectrum of the light reflection layer (measured from the normal direction of the cholesteric liquid crystal layer) is measured using a spectrophotometer UV3150 (Shimadzu Corporation), a peak of reduced transmittance is observed in the selective reflection region.
  • the wavelength value on the short wavelength side is ⁇ l (nm)
  • the wavelength value on the long wavelength side is ⁇ h (nm )
  • the center wavelength and the full width at half maximum of selective reflection can be expressed by the following equations.
  • the center wavelength ⁇ of selective reflection possessed by the cholesteric liquid crystal layer, obtained as described above, usually coincides with the wavelength at the center of gravity of the reflection peak of the circularly polarized reflection spectrum measured from the normal direction of the cholesteric liquid crystal layer.
  • the center wavelength of selective reflection means the center wavelength when measured from the normal direction of the cholesteric liquid crystal layer.
  • the center wavelength of selective reflection can be adjusted by adjusting the pitch of the helical structure.
  • the center wavelength ⁇ can be adjusted in order to selectively reflect either the right circularly polarized light or the left circularly polarized light with respect to light of a desired wavelength by adjusting the n value and the P value.
  • n ⁇ P the center wavelength of selective reflection when a light beam passes at an angle of ⁇ 2 with respect to the normal direction of the cholesteric liquid crystal layer (helical axis direction of the cholesteric liquid crystal layer) is ⁇ d .
  • ⁇ d n 2 ⁇ P ⁇ cos ⁇ 2
  • the central wavelength of selective reflection of the cholesteric liquid crystal layer included in the circularly polarized light reflection layer is designed in consideration of the above, thereby making it possible to see the image from an oblique direction. Can be prevented. Also, the visibility of the image from an oblique direction can be intentionally reduced. Further, due to the selective reflection property described above, in the half mirror of the present invention or the mirror with an image display function including the half mirror of the present invention, a color may appear in an image viewed from an oblique direction or a mirror reflection image.
  • the center wavelength of selective reflection in the infrared region is specifically 780 to 900 nm, preferably 780 to 850 nm.
  • a cholesteric liquid crystal layer having a central wavelength of selective reflection is provided in the infrared light region, it is preferably outermost with respect to all the cholesteric liquid crystal layers each having a central wavelength of selective reflection in the visible light region. More preferably in a distant layer.
  • the pitch of the cholesteric liquid crystal phase depends on the type of chiral agent used together with the polymerizable liquid crystal compound or the concentration of the chiral agent, a desired pitch can be obtained by adjusting these.
  • a desired pitch can be obtained by adjusting these.
  • the circularly polarized light reflection layer includes a cholesteric liquid crystal layer having a central wavelength of selective reflection in the wavelength range of red light, a cholesteric liquid crystal layer having a central wavelength of selective reflection in the wavelength range of green light, and a wavelength of blue light. And a cholesteric liquid crystal layer having a central wavelength of selective reflection in the region.
  • the reflective layer is, for example, a cholesteric liquid crystal layer having a central wavelength of selective reflection in 400 nm to 500 nm, a cholesteric liquid crystal layer having a central wavelength of selective reflection in 500 nm to 580 nm, and a cholesteric liquid crystal having a central wavelength of selective reflection in 580 nm to 700 nm. It is preferable to include a layer.
  • the circularly polarized light reflecting layer includes a plurality of cholesteric liquid crystal layers
  • the cholesteric liquid crystal layer closer to the image display device has a longer selective reflection center wavelength.
  • the center wavelength of selective reflection that each cholesteric liquid crystal layer has is 5 nm or more with the wavelength of the emission peak of the image display device. It is preferable to make them different. This difference is more preferably 10 nm or more.
  • the wavelength of the emission peak of the image display device can be confirmed by the emission spectrum when the image display device displays white.
  • the peak wavelength may be any peak wavelength in the visible light region of the emission spectrum.
  • the above-described red light emission peak wavelength ⁇ R, green light emission peak wavelength ⁇ G, and blue light emission peak wavelength ⁇ B of the image display device Any one or more selected from the group consisting of:
  • the selective reflection center wavelength of the cholesteric liquid crystal layer is different from the above-described red light emission peak wavelength ⁇ R, green light emission peak wavelength ⁇ G, and blue light emission peak wavelength ⁇ B of the image display device by 5 nm or more. It is preferable that the difference is 10 nm or more.
  • the central wavelength of selective reflection of all the cholesteric liquid crystal layers is preferably 5 nm or more, more preferably 10 nm or more, with the peak wavelength of light emitted from the image display device. It should be different.
  • the image display device is a full-color display device showing an emission peak wavelength ⁇ R of red light, an emission peak wavelength ⁇ G of green light, and an emission peak wavelength ⁇ B of blue light in the emission spectrum during white display
  • All of the central wavelengths of selective reflection of the cholesteric liquid crystal layer may be different from each of ⁇ R, ⁇ G, and ⁇ B by 5 nm or more, more preferably by 10 nm or more.
  • the circularly polarized light reflecting layer includes three cholesteric liquid crystal layers having different central wavelengths of selective reflection represented by ⁇ 1, ⁇ 2, and ⁇ 3, the relationship of ⁇ B ⁇ 1 ⁇ G ⁇ 2 ⁇ R ⁇ 3 is established. It is preferable that it is satisfy
  • a half mirror When a half mirror is used as a mirror with an image display function, light is used by adjusting the center wavelength of selective reflection of the cholesteric liquid crystal layer to be used according to the emission wavelength range of the image display device and the usage mode of the circularly polarized reflection layer. A bright image can be displayed efficiently.
  • the usage of the circularly polarized light reflecting layer include an incident angle of light to the circularly polarized light reflecting layer, an image observation direction, and the like.
  • each cholesteric liquid crystal layer a cholesteric liquid crystal layer whose spiral sense is either right or left is used.
  • the sense of reflected circularly polarized light in the cholesteric liquid crystal layer coincides with the sense of a spiral.
  • the spiral senses of the plurality of cholesteric liquid crystal layers may all be the same or different. In other words, either the right or left sense cholesteric liquid crystal layer may be included, or both the right and left sense cholesteric liquid crystal layers may be included.
  • the spiral senses of the plurality of cholesteric liquid crystal layers are all the same.
  • the spiral sense at that time may be determined according to the sense of circularly polarized light of the sense obtained as each cholesteric liquid crystal layer emitted from the image display device and transmitted through the quarter-wave plate. Specifically, a cholesteric liquid crystal layer having a spiral sense that transmits the circularly polarized light of the sense obtained from the image display device and transmitted through the quarter wavelength plate may be used.
  • ⁇ n can be adjusted by adjusting the kind of the polymerizable liquid crystal compound and the mixing ratio thereof, or by controlling the temperature at the time of fixing the alignment.
  • a plurality of cholesteric liquid crystal layers having the same pitch P and the same spiral sense may be stacked. By laminating cholesteric liquid crystal layers having the same pitch P and the same spiral sense, the circularly polarized light selectivity can be increased at a specific wavelength.
  • the half mirror When the half mirror is used as a mirror with an image display function, the half mirror further includes a quarter wavelength plate, a molded resin layer, a polarizing reflector (preferably a circularly polarizing reflector layer, more preferably a cholesteric circularly polarizing reflector layer). ) And a quarter-wave plate in this order. It is preferable that the polarizing reflection plate and the quarter wavelength plate are in direct contact with each other.
  • the quarter-wave plate is preferably disposed so as to be between the image display device and the cholesteric circularly polarizing reflection layer.
  • the light from the image display device displaying an image by linearly polarized light is converted into circularly polarized light, and the cholesteric circularly polarized light is converted. It is possible to make the light incident on the reflective layer. Therefore, the light reflected by the circularly polarized light reflection layer and returning to the image display device side can be greatly reduced, and a bright image can be displayed.
  • a cholesteric circularly polarized light reflection layer can be configured not to generate sense circularly polarized light reflected to the image display device side by using a quarter wavelength plate, it is based on multiple reflections between the image display device and the half mirror.
  • the image display quality is unlikely to deteriorate. That is, for example, the center wavelength of selective reflection of the cholesteric liquid crystal layer included in the cholesteric circularly polarizing reflection layer is substantially the same as the emission peak wavelength of blue light in the emission spectrum during white display of the image display device (for example, the difference is less than 5 nm). Even in such a case, the emitted light of the image display device can be transmitted to the observation surface side without causing the circularly polarized light reflection layer to generate the sense circularly polarized light reflected to the image display side.
  • the quarter-wave plate used in combination with the cholesteric circularly polarized reflective layer is preferably angle-adjusted so that the image is brightest when bonded to the image display device. That is, the relationship between the polarization direction of the linearly polarized light (transmission axis) and the slow axis of the quarter-wave plate so that the linearly polarized light is transmitted best, particularly for an image display device displaying an image by linearly polarized light. Is preferably adjusted. For example, in the case of a single layer type quarter wave plate, it is preferable that the transmission axis and the slow axis form an angle of 45 °.
  • the light emitted from the image display device displaying an image by linearly polarized light is circularly polarized light of either right or left sense after passing through the quarter wavelength plate.
  • the circularly polarized light reflecting layer may be formed of a cholesteric liquid crystal layer having a twist direction that transmits the circularly polarized light having the above-described sense.
  • the quarter wave plate may be a retardation layer that functions as a quarter wave plate in the visible light region.
  • the quarter wavelength plate include a single layer type quarter wavelength plate, a broadband quarter wavelength plate in which a quarter wavelength plate and a half wavelength plate are laminated, and the like.
  • the front phase difference of the former quarter-wave plate may be a length that is 1 ⁇ 4 of the emission wavelength of the image display device. Therefore, for example, when the emission wavelength of the image display device is 450 nm, 530 nm, or 640 nm, the wavelength of 450 nm is preferably 112.5 nm ⁇ 10 nm, more preferably 112.5 nm ⁇ 5 nm, still more preferably 112.5 nm, 530 nm.
  • a reverse-dispersion retardation layer that is a phase difference is most preferable as the quarter-wave plate, but a retardation plate having a small retardation wavelength dispersion or a forward-dispersion retardation plate can also be used.
  • the reverse dispersion means a property that the absolute value of the phase difference becomes larger as the wavelength becomes longer, and the forward dispersion means a property that the absolute value of the phase difference becomes larger as the wavelength becomes shorter.
  • the laminated quarter-wave plate is composed of a quarter-wave plate and a half-wave plate that are bonded to each other with the slow axis at an angle of 60 °, and the half-wave plate side is disposed on the incident side of linearly polarized light.
  • the slow axis of the half-wave plate is used so as to cross 15 ° or 75 ° with respect to the polarization plane of the incident linearly polarized light, and is preferable because the reverse dispersion of the phase difference is good. Can be used.
  • quartz plate stretched polycarbonate film, stretched norbornene polymer film, transparent film containing inorganic particles exhibiting birefringence such as strontium carbonate, and oblique deposition of inorganic dielectric on support Thin films and the like.
  • the quarter-wave plate examples include (1) a birefringent film having a large retardation and a birefringence having a small retardation described in JP-A-5-27118 and JP-A-5-27119.
  • 00/26705 pamphlet which can achieve a quarter wavelength in a wide wavelength range by laminating two polymer films.
  • a commercially available product can also be used as the 1 ⁇ 4 wavelength plate. Examples of the commercially available product include Pure Ace (registered trademark) WR (polycarbonate film manufactured by Teijin Limited).
  • the quarter wavelength plate may be formed by arranging and fixing a polymerizable liquid crystal compound or a polymer liquid crystal compound.
  • a liquid crystal composition is applied to the temporary support or the alignment film surface, and after forming a polymerizable liquid crystal compound in the liquid crystal composition in a nematic alignment in a liquid crystal state, photocrosslinking or thermal crosslinking is performed. Can be formed by immobilization. Details of the liquid crystal composition or the production method will be described later.
  • the quarter-wave plate is aligned by applying a liquid crystal composition on the surface of a temporary support, support or alignment film to form a nematic alignment in a liquid crystal state and then cooling the composition containing a polymer liquid crystal compound. It may be a layer obtained by immobilizing.
  • the quarter wave plate may be adhered to the cholesteric circularly polarized light reflecting layer by an adhesive layer, or may be in direct contact with the latter, and the latter is preferred.
  • a preparation material and a preparation method of a quarter-wave plate formed from a cholesteric liquid crystal layer and a liquid crystal composition will be described.
  • the material used for forming the quarter wavelength plate include a liquid crystal composition containing a polymerizable liquid crystal compound.
  • Examples of the material used for forming the cholesteric liquid crystal layer include a liquid crystal composition containing a chiral agent (optically active compound).
  • the above liquid crystal composition mixed with a surfactant or a polymerization initiator and dissolved in a solvent is used as a temporary support, a support, an alignment film, a lower cholesteric liquid crystal layer, a quarter-wave plate. After the alignment ripening, the liquid crystal composition is fixed by curing, and a cholesteric liquid crystal layer or a quarter wavelength plate can be formed.
  • a rod-like liquid crystal compound may be used as the polymerizable liquid crystal compound.
  • the rod-like polymerizable liquid crystal compound include a rod-like nematic liquid crystal compound.
  • rod-like nematic liquid crystal compounds include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines.
  • Phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles are preferably used. Not only low-molecular liquid crystal compounds but also high-molecular liquid crystal compounds can be used.
  • the polymerizable liquid crystal compound can be obtained by introducing a polymerizable group into the liquid crystal compound.
  • the polymerizable group include an unsaturated polymerizable group, an epoxy group, and an aziridinyl group, preferably an unsaturated polymerizable group, and particularly preferably an ethylenically unsaturated polymerizable group.
  • the polymerizable group can be introduced into the molecule of the liquid crystal compound by various methods.
  • the number of polymerizable groups possessed by the polymerizable liquid crystal compound is preferably 1 to 6, more preferably 1 to 3. Examples of polymerizable liquid crystal compounds are described in Macromol. Chem. 190, 2255 (1989), Advanced Materials, 5, 107 (1993), US Pat. No.
  • the addition amount of the polymerizable liquid crystal compound in the liquid crystal composition is preferably 80% by mass to 99.9% by mass with respect to the solid content mass (mass excluding the solvent) of the liquid crystal composition, 85 It is more preferably from 9% by mass to 99.5% by mass, and particularly preferably from 90% by mass to 99% by mass.
  • the liquid crystal composition used for forming the cholesteric liquid crystal layer preferably contains a chiral agent.
  • the chiral agent has a function of inducing a helical structure of a cholesteric liquid crystal phase.
  • the chiral compound may be selected according to the purpose because the helical sense or helical pitch induced by the compound is different. There is no restriction
  • Examples of chiral agents include liquid crystal device handbook (Chapter 3, Section 4-3, TN, chiral agent for STN, page 199, edited by Japan Society for the Promotion of Science, 142th Committee, 1989), Japanese Patent Application Laid-Open No. 2003-287623. And compounds described in JP-A Nos. 2002-302487, 2002-80478, 2002-80851, 2010-181852 and 2014-034581.
  • a chiral agent generally contains an asymmetric carbon atom, but an axially asymmetric compound or a planar asymmetric compound containing no asymmetric carbon atom can also be used as the chiral agent.
  • the axial asymmetric compound or the planar asymmetric compound include binaphthyl, helicene, paracyclophane, and derivatives thereof.
  • the chiral agent may have a polymerizable group. When both the chiral agent and the liquid crystal compound have a polymerizable group, they are derived from the repeating unit derived from the polymerizable liquid crystal compound and the chiral agent by a polymerization reaction between the polymerizable chiral agent and the polymerizable liquid crystal compound.
  • the polymerizable group possessed by the polymerizable chiral agent is preferably the same group as the polymerizable group possessed by the polymerizable liquid crystal compound. Therefore, the polymerizable group of the chiral agent is also preferably an unsaturated polymerizable group, an epoxy group or an aziridinyl group, more preferably an unsaturated polymerizable group, and an ethylenically unsaturated polymerizable group. Particularly preferred.
  • the chiral agent may be a liquid crystal compound.
  • an isosorbide derivative As the chiral agent, an isosorbide derivative, an isomannide derivative, or a binaphthyl derivative can be preferably used.
  • an isosorbide derivative a commercial product such as LC-756 manufactured by BASF may be used.
  • the content of the chiral agent in the liquid crystal composition is preferably from 0.01 mol% to 200 mol%, more preferably from 1.0 mol% to 30 mol%, based on the total molar amount of the polymerizable liquid crystal compound.
  • the liquid crystal composition preferably contains a polymerization initiator.
  • the polymerization initiator to be used is preferably a photopolymerization initiator capable of initiating the polymerization reaction by ultraviolet irradiation, and particularly preferably a radical photopolymerization initiator.
  • radical photopolymerization initiators include ⁇ -carbonyl compounds (described in US Pat. Nos. 2,367,661 and 2,367,670), acyloin ether (described in US Pat. No. 2,448,828), ⁇ -hydrocarbon substitution Aromatic acyloin compounds (described in US Pat. No.
  • acyl phosphine oxide compound As the polymerization initiator, it is also preferable to use an acyl phosphine oxide compound or an oxime compound.
  • acylphosphine oxide compound for example, IRGACURE819 (compound name: bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide) manufactured by BASF Japan Ltd. can be used.
  • Examples of the oxime compounds include IRGACURE OXE01 (manufactured by BASF), IRGACURE OXE02 (manufactured by BASF), TR-PBG-304 (manufactured by Changzhou Strong Electronic New Materials Co., Ltd.), Adeka Arcles NCI-831, Adeka Arcles NCI-930 Commercial products such as (ADEKA) and Adeka Arcles NCI-831 (ADEKA) can be used.
  • the content of the polymerization initiator in the liquid crystal composition is preferably 0.1 to 20% by mass, and preferably 0.5 to 5.0% by mass with respect to the content of the polymerizable liquid crystal compound. Is more preferable.
  • the liquid crystal composition may optionally contain a crosslinking agent in order to improve the film strength after curing and improve the durability.
  • a crosslinking agent one that can be cured by ultraviolet rays, heat, moisture, or the like can be suitably used.
  • polyfunctional acrylate compounds such as a trimethylol propane tri (meth) acrylate and pentaerythritol tri (meth) acrylate
  • Glycidyl (meth) acrylate Epoxy compounds such as ethylene glycol diglycidyl ether; aziridine compounds such as 2,2-bishydroxymethylbutanol-tris [3- (1-aziridinyl) propionate], 4,4-bis (ethyleneiminocarbonylamino) diphenylmethane; hexa Isocyanate compounds such as methylene diisocyanate and biuret type isocyanate; polyoxazoline compounds having an oxazoline group in the side chain; vinyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropylto Alkoxysilane compounds such as methoxy silane.
  • a well-known catalyst can be used according to the reactivity of a crosslinking agent, and productivity can be improved in addition to membrane strength and durability improvement. These may be used individually by 1 type and may use 2 or more types together.
  • the content of the crosslinking agent in the liquid crystal composition is preferably 3.0% by mass to 20% by mass, and more preferably 5.0% by mass to 15% by mass. When the content of the crosslinking agent is 3.0% by mass or more, an effect of improving the crosslinking density can be obtained. Moreover, the stability of the layer formed can be maintained by setting it as 20 mass% or less.
  • an alignment control agent that contributes to stable or rapid planar alignment may be added.
  • the alignment control agent include fluorine (meth) acrylate polymers described in paragraphs 0018 to 0043 of JP 2007-272185 A, and formulas (I) described in paragraphs 0031 to 0034 of JP 2012-203237 A, and the like.
  • To (IV) 1 type may be used independently and 2 or more types may be used together.
  • the addition amount of the alignment control agent in the liquid crystal composition is preferably 0.01% by mass to 10% by mass and more preferably 0.01% by mass to 5.0% by mass with respect to the total mass of the polymerizable liquid crystal compound. 0.02% by mass to 1.0% by mass is particularly preferable.
  • the liquid crystal composition may contain at least one selected from a surfactant for adjusting the surface tension of the coating film to make the thickness uniform, and various additives such as a polymerizable monomer.
  • a polymerization inhibitor, an antioxidant, an ultraviolet absorber, a light stabilizer, a colorant, metal oxide fine particles, and the like may be added as long as the optical performance is not deteriorated. Can be added.
  • solvent there is no restriction
  • the organic solvent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include ketones, alkyl halides, amides, sulfoxides, heterocyclic compounds, hydrocarbons, esters, ethers and the like. Can be mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, ketones are particularly preferable in consideration of environmental load.
  • the method for applying the liquid crystal composition to the temporary support, the alignment film, the quarter-wave plate, the lower cholesteric liquid crystal layer, etc. is not particularly limited and can be appropriately selected according to the purpose.
  • the application method in this specification includes, for example, a wire bar coating method, a curtain coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, and a die coating method. , Spin coating method, dip coating method, spray coating method, slide coating method and the like. It can also be carried out by transferring a liquid crystal composition separately coated on a support. The liquid crystal compound is aligned by heating the applied liquid crystal composition.
  • cholesteric alignment may be performed, and in forming the quarter-wave plate, nematic alignment is preferable.
  • the heating temperature is preferably 200 ° C. or lower, and more preferably 130 ° C. or lower.
  • the heating temperature is preferably 50 ° C. to 120 ° C., more preferably 60 ° C. to 100 ° C.
  • the aligned liquid crystal compound can be further polymerized to cure the liquid crystal composition.
  • the polymerization may be either thermal polymerization or photopolymerization utilizing light irradiation, but photopolymerization is preferred. It is preferable to use ultraviolet rays for light irradiation.
  • the irradiation energy is preferably 20mJ / cm 2 ⁇ 50J / cm 2, 100mJ / cm 2 ⁇ 1,500mJ / cm 2 is more preferable.
  • light irradiation may be performed under heating conditions or in a nitrogen atmosphere.
  • the irradiation ultraviolet wavelength is preferably 350 nm to 430 nm.
  • the polymerization reaction rate is preferably high from the viewpoint of stability, more preferably 70% or more, and further preferably 80% or more.
  • the polymerization reaction rate can be determined by measuring the consumption rate of the polymerizable group using an IR absorption spectrum.
  • each cholesteric liquid crystal layer is not particularly limited as long as it exhibits the above characteristics, and is preferably in the range of 0.5 to 100 ⁇ m, more preferably in the range of 1.0 to 40 ⁇ m.
  • the thickness of the quarter wave plate formed from the liquid crystal composition is not particularly limited, and is preferably 0.2 ⁇ m to 10 ⁇ m, more preferably 0.5 ⁇ m to 2.0 ⁇ m.
  • the liquid crystal on the air interface side of the cholesteric liquid crystal layer formed earlier is formed by forming the next cholesteric liquid crystal layer so as to be in direct contact with the surface of the cholesteric liquid crystal layer formed earlier. This is because the orientation direction of the molecules matches the orientation direction of the liquid crystal molecules below the cholesteric liquid crystal layer formed thereon, and the polarization property of the laminate of the cholesteric liquid crystal layer is improved.
  • the liquid crystal composition is preferably applied and layered on the surface of a support, a temporary support, or an alignment layer formed on the surface of the support or the temporary support.
  • the support may not be peeled after the layer is formed, and the temporary support, or the temporary support and the alignment layer may be peeled after the layer is formed.
  • the temporary support and the support include a plastic film or a glass plate.
  • the material of the plastic film include polyesters such as polyethylene terephthalate (PET), polycarbonate, acrylic resin, epoxy resin, polyurethane, polyamide, polyolefin, cellulose derivative, and silicone.
  • PET polyethylene terephthalate
  • the temporary support which is a plastic film functions as a base film of a transfer sheet described later.
  • the temporary support may function as a protective film until the half mirror is used, for example, until it is adhered to the image display device.
  • the alignment layer has a rubbing treatment of organic compounds such as polymers (resins such as polyimide, polyvinyl alcohol, polyester, polyarylate, polyamideimide, polyetherimide, polyamide, modified polyamide), oblique deposition of inorganic compounds, and microgrooves. It can be provided by means such as formation of a layer or accumulation of an organic compound (for example, ⁇ -tricosanoic acid, dioctadecylmethylammonium chloride, methyl stearylate) using the Langmuir-Blodgett method (LB method). Further, an alignment layer that generates an alignment function by application of an electric field, application of a magnetic field, or light irradiation may be used.
  • organic compounds such as polymers (resins such as polyimide, polyvinyl alcohol, polyester, polyarylate, polyamideimide, polyetherimide, polyamide, modified polyamide), oblique deposition of inorganic compounds, and microgrooves.
  • the alignment layer made of a polymer is preferably subjected to a rubbing treatment and then a liquid crystal composition is applied to the rubbing treatment surface.
  • the rubbing treatment can be performed by rubbing the surface of the polymer layer several times in a certain direction with paper or cloth.
  • the liquid crystal composition may be applied to the surface of the temporary support without providing the alignment layer, or to the surface on which the temporary support has been rubbed.
  • the thickness of the alignment layer is preferably 0.01 ⁇ m to 5.0 ⁇ m, and more preferably 0.05 ⁇ m to 2.0 ⁇ m.
  • the half mirror of the present invention includes a high Re retardation film.
  • the term “high Re phase difference film” means a phase difference film having a high front phase difference, which is distinguished from a quarter wave plate (phase difference plate). At least one high Re retardation film is included between the observation surface and the polarizing reflector.
  • the half mirror of the present invention preferably includes one or two high Re retardation films.
  • the half mirror of the present invention includes the first high Re retardation film as the high Re retardation film between the observation surface and the molded resin layer.
  • the half mirror of the present invention preferably includes only the first high Re retardation film as the high Re retardation film.
  • a second high Re retardation film is further provided as a high Re retardation film between the molded resin layer and the polarizing reflector. It is preferable to include. That is, it is preferable that high Re retardation films are disposed on both surfaces of the molded resin layer. In the present specification, when it is simply described as “high Re retardation film”, it corresponds to both “first high Re retardation film” and “second high Re retardation film”.
  • the direction of the slow axis of the two or more High Re retardation films is preferably the same.
  • the direction of the slow axis of the first high Re retardation film and the second The direction of the slow axis of the high Re retardation film is preferably the same.
  • the total front retardation of the high Re retardation film is preferably 3000 nm or more, and more preferably 5000 nm or more.
  • the total front retardation of the high Re retardation film is preferably as large as possible, but is preferably 100000 nm or less, more preferably 50000 nm or less, still more preferably 40000 nm or less, and particularly preferably 30000 nm or less in consideration of production efficiency and thinning.
  • the front retardation of the first high Re retardation film is preferably 3000 nm or more.
  • the front retardation of each high Re retardation film is preferably 1500 nm or more, more preferably 2000 nm or more, More preferably, it is 3000 nm or more. Further, it is preferable that the front phase differences of two or more high Re retardation films are equal to each other because manufacturing is easy.
  • the front retardation of the first high Re retardation film and the second high Re retardation film Are preferably equal.
  • the molded resin layer tends to have non-uniform birefringence.
  • a half mirror is used for a mirror with an image display function
  • the light for forming an image is transmitted through the molding resin layer, and therefore the image is observed through polarized sunglasses under the influence of the non-uniform birefringence described above. Then, light and dark unevenness and color unevenness occur.
  • the mirror reflection image is also observed by the light that has passed through the molding resin layer twice, it is affected by the above-mentioned non-uniform birefringence, and when the image is observed through polarized sunglasses, light and dark unevenness or color unevenness occurs.
  • tempered glass for example, tempered glass which is not a laminated glass
  • vehicle window glass particularly rear glass
  • tempered glass has a birefringence distribution. For this reason, it is considered that light and dark unevenness or color unevenness occurs in the mirror reflection image based on the light that passes through the rear glass of the vehicle and enters the front surface of the mirror with an image display function.
  • the front phase difference that can make the polarized light pseudo-non-polarized is described in paragraphs 0022 to 0033 of JP-A-2005-321544.
  • the specific numerical value of the front phase difference can be determined according to the molded resin layer and, when used as a mirror with a vehicle image display function described later, according to the molded resin layer and the vehicle.
  • the high Re retardation film examples include a birefringent material such as a plastic film and a quartz plate.
  • the plastic film examples include polyester films such as polyethylene terephthalate (PET), polycarbonate films, polyacetal films, polyarylate films, and the like. JP-A-2013-257579, JP-A-2015-102636, and the like can be referred to for a retardation film having a high retardation including PET.
  • Commercial products such as optical Cosmo Shine (registered trademark) super birefringence type (Toyobo) may be used.
  • plastic films with high phase difference are melt extruded and cast on a drum or the like to form a film, which is heated and stretched uniaxially or biaxially 2 to 5 times. It can be formed by stretching at a magnification.
  • a heat treatment called “heat setting” may be performed at a temperature exceeding the stretching temperature after stretching.
  • a high Re retardation film may be produced by laminating a plurality of films having a retardation. Other layers such as an adhesive layer may be included between the films having a plurality of retardations.
  • the thickness of the high Re retardation film is preferably 1.0 ⁇ m to 10,000 ⁇ m, more preferably 10 ⁇ m to 1000 ⁇ m, and even more preferably 20 ⁇ m to 200 ⁇ m.
  • the half mirror of the present invention may include an optical function layer.
  • the optical functional layer is preferably provided so that the optical functional layer, the first high Re retardation film, the molded resin layer, and the reflective polarizing plate are in this order.
  • an optical functional layer that is transparent in the visible light region is used. Examples of the optical functional layer include a hard coat layer, an antiglare layer, an antireflection layer, and an antistatic layer.
  • the optical functional layer is preferably a cured layer of a polymerizable composition provided on the first high Re retardation film.
  • the optical functional layer is preferably provided on the molded resin layer after being provided on the first high Re retardation film and then being integrated with the first high Re retardation film.
  • the hard coat layer may be included as the outermost layer of the half mirror, and another layer may be provided outside the hard coat layer.
  • the hard coat layer refers to a layer that, when formed, increases the pencil hardness of the half mirror surface. Specifically, it is a layer having a pencil hardness (JIS K5400) of H or higher after the hard coat layer lamination.
  • the pencil hardness after laminating the hard coat layer is preferably 2H or more, and more preferably 3H or more.
  • the thickness of the hard coat layer is preferably 0.1 ⁇ m to 100 ⁇ m, more preferably 1.0 ⁇ m to 70 ⁇ m, and further preferably 2.0 ⁇ m to 50 ⁇ m.
  • the hard coat layer may also serve as an antireflection layer or an antistatic layer.
  • the hard coat layer include a layer formed from a composition containing an ultraviolet curable polymerizable compound.
  • the composition may contain other components such as particles.
  • As the ultraviolet curable polymerizable compound (meth) acrylate is preferable.
  • As for the material and the production method of the hard coat layer reference can be made to JP-A-2016-071085, JP-A-2012-168295, JP-A-2011-225846, and the like.
  • the antiglare layer is a layer for imparting antiglare properties based on surface scattering.
  • the antiglare layer may be included as the outermost layer of the half mirror, and another layer may be further provided outside the antiglare layer.
  • the antiglare layer can be formed from a composition containing a binder resin-forming compound for the antiglare layer and particles for the antiglare layer.
  • material and production method of the antiglare layer reference can be made to the descriptions of 0101 to 0109 of JP2013-178484A, JP2016-053601A, and the like.
  • the antireflection layer is preferably included on the outermost surface of the half mirror. By providing the antireflection layer, the reflected light on the outermost surface is suppressed, and a mirror reflection image based on an image derived from the light from the polarizing reflection plate can be clearly observed.
  • the description in 0049 to 0053 of WO2015 / 050202A can be referred to.
  • the antistatic layer is preferably contained on the outermost surface of the half mirror.
  • the half mirror may include an adhesive layer for bonding the layers.
  • the adhesive layer may be formed from an adhesive. It is preferable to include an adhesive layer between the molded resin layer and the polarizing reflector. Moreover, it is preferable that an adhesive layer is included between the first high Re retardation film and the molded resin layer. Moreover, it is preferable that an adhesive layer is included between the second high Re retardation film and the molded resin layer.
  • Adhesives include thermal curing type, photocuring type, reaction curing type, and pressure-sensitive adhesive type that does not require curing, from the viewpoint of curing method, and acrylate, urethane, urethane acrylate, epoxy, epoxy as materials It is possible to use compounds such as acrylate, polyolefin, modified olefin, polypropylene, ethylene vinyl alcohol, vinyl chloride, chloroprene rubber, cyanoacrylate, polyamide, polyimide, polystyrene, polyvinyl butyral, etc. it can. From the viewpoint of workability and productivity, the photocuring type is preferable as the curing method, and from the viewpoint of optical transparency and heat resistance, it is preferable to use an acrylate, urethane acrylate, epoxy acrylate, or the like material.
  • a pressure-sensitive adhesive type adhesive layer that does not require curing can be formed using a sheet-like commercially available adhesive layer. You may form using what is called a highly transparent adhesive transfer tape (OCA tape).
  • OCA tape a highly transparent adhesive transfer tape
  • a commercially available product for an image display device particularly a commercially available product for the image display unit surface of the image display device may be used. Examples of commercially available products include PANAC Corporation pressure-sensitive adhesive sheets (PD-S1 and the like), MHI Series MHM series pressure-sensitive adhesive sheets, and the like.
  • adhesion between the molded resin layer and the high Re retardation film can be performed by a pressure-sensitive adhesive type adhesive layer that does not require curing.
  • the half mirror may include a thermoplastic weld layer.
  • the thermoplastic weld layer is used for adhesion between the layers.
  • the thermoplastic weld layer is melted by heating and then cooled to adhere the layers.
  • the thermoplastic weld layer is preferably used for adhesion between the molded resin layer and another layer, and the thermoplastic weld layer and the molded resin layer are preferably in direct contact with each other.
  • the thermoplastic welding layer is used when a high Re phase difference film or a polarizing reflector is provided on one surface of the molded resin layer at the same time as the production of the molded resin layer by injection molding, as will be described later.
  • the molded resin layer and the thermoplastic weld layer may form a mixed layer in which both components are mixed.
  • a mixed layer may be formed between the molded resin layer and the thermoplastic weld layer. It is preferable to include a thermoplastic weld layer between the molded resin layer and the polarizing reflector. Moreover, it is preferable that a thermoplastic weld layer is included between the first high Re retardation film and the molded resin layer. Moreover, it is preferable that a thermoplastic weld layer is included between the second high Re retardation film and the molded resin layer.
  • the thermoplastic weld layer contains a thermoplastic resin.
  • thermoplastic resins include vinyl chloride resin, vinyl acetate resin, copolymer resin of vinyl chloride and vinyl acetate, copolymer resin of ethylene and vinyl acetate, copolymer resin of isobutene and maleic anhydride, (meta ) Acrylic resin, (meth) acrylic copolymer resin, copolymer resin of styrene and butadiene, urethane resin, polyester resin, epoxy resin, silicone resin, modified silicone resin, rosin resin, polyvinyl acetal resin, chloroprene rubber, nitrile rubber, A nitrile resin etc. are mentioned.
  • the thickness of the thermoplastic weld layer may be 0.1 ⁇ m to 100 ⁇ m, preferably 0.5 ⁇ m to 30 ⁇ m, and more preferably 1.0 ⁇ m to 8.0 ⁇ m.
  • the thickness of the thermoplastic weld layer may be 0.1 ⁇ m to 100 ⁇ m, preferably 0.5 ⁇ m to 30 ⁇ m, and more preferably 1.0 ⁇ m to 8.0 ⁇ m.
  • the thermoplastic welding layer can be formed by applying a coating liquid containing a thermoplastic resin to the surface of a polarizing reflection layer or a release sheet.
  • Solvents for coating solutions include amides (eg, N, N-dimethylformamide), sulfoxides (eg, dimethyl sulfoxide), heterocyclic compounds (eg, pyridine), hydrocarbons (eg, benzene, hexane, cyclohexane), alkyl halides (Eg, chloroform, dichloromethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane), alkyl alcohols (Eg, methanol, ethanol, propanol).
  • amides eg,
  • thermoplastic weld layer Two or more kinds of solvents may be mixed and used. Among the above, alkyl halides, esters, ketones and mixed solvents thereof are preferable.
  • a commercially available composition as it is as a heat sealant, or a solution dissolved in a solvent or a solution diluted with a solvent can be used.
  • the half mirror of the present invention may be manufactured by adhering each layer using an adhesive layer, and at the same time as manufacturing of a molded resin layer by injection molding or the like, a high Re retardation film or a polarizing reflector is formed as a molded resin layer. It may be produced by providing on one of the surfaces and further bonding another layer to the surface using an adhesive layer.
  • a half mirror including only the first high Re retardation film as the high Re retardation film can be obtained, for example, by any of the following procedures. Adhering a polarizing reflector on one main surface side of the molded resin layer and a first high Re retardation film on the other main surface side using an adhesive layer; one of the molded resin layers simultaneously with the production of the molded resin layer A polarizing reflector is provided on the main surface side of the first, and the first high Re retardation film is adhered to the other main surface side using an adhesive layer; one main surface side of the molded resin layer simultaneously with the production of the molded resin layer The first high-Re retardation film is provided on the other main surface, and the polarizing reflector is adhered to the other main surface side by using an adhesive layer; The first high Re retardation film is provided on the other main surface side.
  • the half mirror including the first high Re phase difference film and the second high Re phase difference film as the high Re phase difference film can be obtained by any of the following procedures, for example.
  • a first high Re phase difference film is adhered to one main surface side of the molded resin layer, and a second high Re phase difference film is adhered to the other main surface side using an adhesive layer, and further, a second high Re level is obtained.
  • a polarizing reflector is adhered to the surface side of the retardation film on which the molded resin layer is not adhered by using an adhesive layer; simultaneously with the production of the molded resin layer, a second high Re phase difference is formed on one main surface side of the molded resin layer.
  • a film is provided and adhered to the second high Re retardation film side of the obtained molded body using an adhesive layer. Thereafter, a first high Re retardation film is adhered to the other main surface side of the molded resin layer using an adhesive layer; simultaneously with the production of the molded resin layer, the first high Re film is formed on one main surface side of the molded resin layer.
  • An Re retardation film is provided, and a polarizing reflector and a second high Re retardation film are adhered in this order using an adhesive layer on the other main surface side; one of the molded resin layers simultaneously with the production of the molded resin layer A first high-Re phase difference film is provided on the main surface side, and a second high-Re phase difference film is provided on the other main surface side, and then bonded to the second high-Re phase difference film side of the obtained molded body. Adhere using layers.
  • the molded resin layer is preferably manufactured by injection molding.
  • Injection molding is a method in which a resin is heated and melted, and then the molten resin is injected into a mold under pressure and solidified or cured to obtain a molded product.
  • the inside of the mold means a space formed by the mold. Usually, the space only needs to be formed by two molds, a male mold and a female mold.
  • the injection speed when the molten resin is pressure-injected and filled into the mold is preferably 1 mm / second to 50 mm / second, and more preferably 5 mm / second to 30 mm / second.
  • Injection molding is performed by cooling the molten resin after it is heated and pressurized in the mold.
  • the heating temperature (mold temperature: surface temperature of the mold inner surface) may be 50 ° C. to 150 ° C., preferably 80 ° C. to 130 ° C.
  • By setting the temperature range to 50 ° C. to 150 ° C. it is possible to suppress the occurrence of sink marks, burrs, flow marks, etc. when the molten resin is injected into the mold under pressure, and the molded resin layer has a stable dimension. Can be obtained.
  • the pressurization may be from 0.01 MPa to 1.0 MPa, preferably from 0.05 MPa to 0.5 MPa, more preferably from 0.1 MPa to 0.3 MPa.
  • the heating and pressurizing time is preferably 1 to 300 seconds, more preferably 10 to 120 seconds.
  • Cooling is preferably performed at room temperature or lower, specifically 10 ° C. to 30 ° C. It is preferable to pressurize before cooling. Furthermore, it is preferable that the pressurized state is maintained during cooling. In general, when the mold temperature is raised, the time until cooling becomes longer, which causes a problem that the molding cycle becomes longer. Therefore, it is preferable to cool the inner surface of the mold in a short time.
  • the inner surface of the mold is preferably cooled at 1 ° C. to 100 ° C./second from the viewpoint of scratch resistance of the molded resin layer.
  • the cooling rate of the inner surface of the mold is more preferably 30 ° C. to 90 ° C./second, and further preferably 40 ° C. to 80 ° C./second.
  • Injection molding can be performed by an injection molding machine.
  • the injection molding machine may have an injection mechanism, a temperature control mechanism, a mold clamping mechanism, and the like in addition to the mold or the part where the mold is installed.
  • the mold is usually a set of two, and the space is formed by clamping the two. Any one of the two plates may be a fixed platen and the other may be a movable platen. One of them may be a female mold and the other may be a male mold.
  • the female die may be a fixed platen or the male die may be a fixed platen, and the female die is preferably a fixed platen.
  • polarizing reflector or high Re retardation film Simultaneously with the production of the molded resin layer, at least one of the polarizing reflector, the first high Re retardation film, and the second high Re retardation film (hereinafter referred to as “polarizing reflector or high Re retardation film”).
  • polarizing reflector or high Re retardation film a method generally known as in-mold molding or insert molding can be used. Which is used is not particularly limited, and it is preferable that the polarizing reflector is provided by in-mold molding, and the high Re retardation film is provided by insert molding.
  • in-mold molding when injection molding is performed, a state in which a molding sheet including a polarizing reflector or a high Re retardation film and a base film is sandwiched between molds, for example, a molding sheet is a two-sheet mold.
  • a polarizing reflector or a high Re retardation film is adhered to the surface of the injection molded product in the mold simultaneously with the injection molding.
  • the molten resin is injected into the mold during the injection molding, and the base film, the polarizing reflector or the high Re retardation film, and the molten resin may be arranged in this order.
  • thermoplastic weld layer When a molding sheet having a thermoplastic weld layer is used, the thermoplastic weld layer and the molten resin such as a base film, a polarizing reflector, or a high Re retardation film are arranged in this order. Thereafter, the base film is peeled from the obtained molded resin layer, a polarizing reflector, a high Re retardation film, and the like, and a molded body including the base film.
  • a half mirror can be manufactured by feeding a roll-shaped molding sheet into a mold and sequentially sandwiching necessary portions of the molding sheet.
  • Insert molding is a state in which a molding sheet including a polarizing reflector or a high Re retardation film is sandwiched between molds when performing injection molding, for example, a state in which a molding sheet is sandwiched between two molds. At the same time as the injection molding, a polarizing reflector or a high Re retardation film is adhered to the surface of the injection molded product in the mold.
  • the molding sheet has a thermoplastic weld layer, the thermoplastic weld layer and the molten resin, such as a polarizing reflector or a high Re retardation film, are arranged in this order. In insert molding, substantially the entire molding sheet is part of the finished product.
  • the molding sheet When the molding sheet is sandwiched between molds, it is preferable that the molding sheet is in contact with the inner surface of the mold.
  • the contact of the molding sheet with the inner surface of the mold only needs to be achieved on at least a part of the molding sheet, and is preferably achieved on substantially the entire area corresponding to the mold. That is, it is preferable that the corresponding area of the molding sheet is in close contact with the entire surface.
  • Contact may be achieved simply by placing the transfer sheet on the mold, or means may be taken to achieve contact. Examples of means for achieving the contact include vacuum suction.
  • vacuum suction reference can be made, for example, to JP-A-10-264201.
  • the molded body obtained by the injection molding may be removed from the mold and then bonded.
  • the base film When the base film is peeled from the molded body obtained by in-mold molding, the base film may be peeled before or after adhesion of the optical functional layer.
  • the molding sheet preferably includes one or more of a polarizing reflector, a first high Re retardation film, and a second high Re retardation film.
  • the molding sheet may include a thermoplastic welding layer.
  • molding may contain the base film.
  • the molding sheet includes a thermoplastic welding layer
  • the polarizing reflector or the high Re retardation film is integrated with the molding resin layer by adhering the thermoplastic welding layer of the molding sheet to the molding resin layer (molten resin).
  • a resin mirror can be obtained.
  • the thermoplastic weld layer is preferably in the outermost layer of the molding sheet.
  • the surface of the outermost layer of the molding sheet for example, the surface of the thermoplastic welding layer, may be provided with a protective layer for protection during transportation, etc., and the protective layer is peeled off when used as a molding sheet May be used.
  • a transfer sheet can be used as a molding sheet for providing a polarizing reflector.
  • a transfer sheet can be used for providing the polarizing reflector on the molded resin layer.
  • the transfer sheet may be a plate or a film.
  • the transfer sheet may be in the form of a roll.
  • the thickness of the transfer sheet may be 1.0 ⁇ m to 300 ⁇ m, preferably 5.0 ⁇ m to 200 ⁇ m. By setting the thickness of the transfer sheet to 1.0 ⁇ m to 300 ⁇ m, it can be formed without generating wrinkles.
  • the transfer sheet has an elongation at room temperature of preferably 5% to 300%, more preferably 10% to 250%, and even more preferably 20% to 200%. The tensile elongation can be measured according to a thin plastic sheet tensile test (ASTM D882).
  • the transfer sheet includes a polarizing reflector.
  • the transfer sheet preferably includes a thermoplastic weld layer.
  • the transfer sheet may include other layers such as a base film, a release layer, an orientation layer, a protective layer, and an adhesive layer.
  • the polarizing reflector and the thermoplastic welding layer may be in direct contact with each other or there may be other layers between them.
  • the transfer sheet the polarizing reflector produced as described above can be used as it is. What has a temporary support body in the case of preparation can use a temporary support body as a base film as it is.
  • a transfer sheet including a thermoplastic welding layer can be produced by forming a thermoplastic welding layer on a polarizing reflector, usually on the surface of the polarizing reflector.
  • thermoplastic welding layer is obtained by applying a coating solution containing a thermoplastic resin on the polarizing reflector and drying it, or transferring the thermoplastic welding layer from the release sheet on which the thermoplastic welding layer is formed onto the polarizing reflector. It can produce by doing.
  • the molding sheet may include a base film.
  • the transfer sheet preferably includes a base film.
  • the same material as the temporary support for applying the liquid crystal composition to form a layer can be used.
  • a preferred example is a polyethylene terephthalate film.
  • the temporary support for forming a layer by applying the liquid crystal composition is the base film of the transfer sheet as it is.
  • the transfer sheet may include an alignment layer used at the time of forming the polarizing reflector, and when the base film is peeled off in the half mirror manufacturing method, the orientation layer may or may not be peeled off at the same time. Good.
  • the thickness of the base film is usually about 5.0 to 200 ⁇ m, preferably about 20 to 100 ⁇ m.
  • the molding sheet may include a release layer.
  • the release layer is provided on the surface of the base film, and is disposed between the base film and the polarizing reflector or the high Re retardation film. It is a layer for facilitating separation, and when the base film is peeled off, it is peeled off together with the base film.
  • the release layer may cover the entire surface of the base film, or may be provided on a part of the base film. Usually, it is preferable to cover the entire surface of the base film in consideration of peelability.
  • the release layer is made of silicone resin, fluorine resin, acrylic resin (for example, acrylic-melamine resin), polyester resin, polyolefin resin, polystyrene resin, polyurethane resin, cellulose resin, chloride resin, Vinyl-vinyl acetate copolymer resins, thermoplastic resins such as nitrified cotton, copolymers of monomers that form this thermoplastic resin, or those modified with (meth) acrylic acid or urethane alone It can be formed by using a resin composition in which two or more are mixed. Among these, acrylic resins, polyester resins, polyolefin resins, polystyrene resins, copolymers of monomers forming these resins, and those obtained by urethane modification thereof are preferable.
  • the release layer is composed of an acrylic-melamine resin alone or a composition containing 50% by mass or more of the acrylic-melamine resin.
  • the thickness of the release layer is usually about 0.01 to 5.0 ⁇ m, preferably about 0.05 to 3.0 ⁇ m.
  • the half mirror can be used for various applications depending on the optical characteristics of the polarizing reflector. Examples of applications include vehicle (on-vehicle) mirrors, optical lenses, eyewear optical members, and the like. Of these, vehicle mirrors are preferred.
  • a mirror with an image display function can be manufactured using the half mirror of the present invention.
  • the mirror with an image display function includes a half mirror and an image display device.
  • the observation surface, the molded resin layer, the polarizing reflector, and the image display device are arranged in this order.
  • the image display device and the half mirror may be in direct contact with each other, an air layer may be present therebetween, or may be directly bonded via an adhesive layer.
  • a half mirror having the same surface area as the area of the image display unit of the image display device may be used, and the half mirror having a surface area larger or smaller than the area of the image display unit of the image display device.
  • a mirror may be used.
  • the slow axis of the quarter wavelength plate is adjusted so that the image is brightest. That is, the relationship between the polarization direction of the linearly polarized light (transmission axis) and the slow axis of the quarter-wave plate so that the linearly polarized light is transmitted best, particularly for an image display device displaying an image by linearly polarized light. Is preferably adjusted. For example, in the case of a quarter wavelength plate, it is preferable that the transmission axis and the slow axis form an angle of 45 °.
  • the light emitted from the image display device displaying an image by linearly polarized light is circularly polarized light of either right or left sense after passing through the quarter wavelength plate.
  • the circularly polarized light reflecting layer described later only needs to be composed of a cholesteric liquid crystal layer having a twist direction that transmits the circularly polarized light of the above-described sense.
  • the image display device is preferably an image display device that emits (emits light) linearly polarized light to form an image.
  • the half mirror of the present invention is arranged so that the slow axis of the high Re retardation film forms an angle of 30 ° to 60 ° with the polarization direction of the linearly polarized light emitted from the image display device, thereby producing a mirror with an image display function.
  • an image having no brightness unevenness or color unevenness can be observed even when observed through polarized sunglasses.
  • the image display device may be a liquid crystal display device.
  • the half mirror of the present invention eliminates light / dark unevenness or color unevenness in an image observed through polarized sunglasses by using it in combination with an image display device having a backlight that gives a continuous emission spectrum as a backlight. be able to.
  • a white LED white light emitting diode
  • the continuous emission spectrum means, for example, an emission spectrum in the visible light region (eg, a spectrum in the visible light region of sunlight) having no wavelength region that does not substantially emit light.
  • Examples of the backlight that gives a continuous emission spectrum include white LEDs, and those that show a discontinuous emission spectrum having a peak at a specific wavelength in the visible light wavelength region, such as a fluorescent lamp, are not included.
  • the liquid crystal display device may be a transmissive type or a reflective type, and is particularly preferably a transmissive type.
  • Liquid crystal display devices include IPS (In-Plane Switching) mode, FFS (Fringe Field Switching) mode, VA (Vertical Alignment) mode, ECB (Electrically Controlled Birefringence) mode, STN (Super Twisted Nematic) mode, and TN (Twisted Nematic) mode. Any liquid crystal display device such as an OCB (Optically Compensated Bend) mode may be used.
  • the image displayed on the image display unit of the image display device may be a still image, a moving image, or simply text information. Further, it may be a monochrome display such as black and white, a multi-color display, or a full-color display.
  • a preferable example of the image displayed on the image display unit of the image display device is an image taken by a vehicle-mounted camera. This image is preferably a moving image.
  • the image display device only needs to indicate the emission peak wavelength ⁇ R of red light, the emission peak wavelength ⁇ G of green light, and the emission peak wavelength ⁇ B of blue light in the emission spectrum during white display.
  • ⁇ R may be any wavelength in the range of 580 nm to 700 nm, preferably in the range of 610 nm to 680 nm.
  • ⁇ G may be any wavelength in the range of 500 nm to 580 nm, preferably in the range of 510 nm to 550 nm.
  • ⁇ B may be any wavelength in the range of 400 nm to 500 nm, preferably in the range of 440 nm to 480 nm.
  • the mirror with an image display function can be manufactured by arranging the half mirror on the image display side of the image display device and integrating the image display device and the half mirror.
  • the half mirror is arranged so that the observation surface, the molded resin layer, the polarizing reflector, and the image display device are in this order.
  • the slow axis of the first high Re retardation film of the half mirror may be arranged so as to form an angle of 30 ° to 60 ° with the polarization direction of the linearly polarized light emitted from the image display device. It is preferable to arrange them at an angle of 40 ° to 50 °.
  • the direction of the slow axis of the first high Re phase difference film and the second high Re phase difference it is preferable to use half mirrors having the same slow axis direction of the film. Since the direction of the slow axis of the first high Re retardation film and the direction of the slow axis of the second high Re retardation film are the same, image unevenness can be reduced efficiently. For example, by using those having the same slow axis direction, even if the front phase difference is about 1500 nm or more and less than 3000 nm, it is possible to reduce image unevenness.
  • the difference between the front phase difference of the first high Re retardation film and the front phase difference of the second high Re retardation film is 3000 nm or more, the image can be obtained even if the slow axis directions of both are different. Unevenness can be reduced.
  • Integrating the image display device and the half mirror may be performed by connecting with a frame or a hinge or bonding.
  • a mirror with an image display function can be manufactured by adhering a half mirror to an image display surface of an image display device. Adhesion is performed so that the molded resin layer, the polarizing reflector, and the image display device are in this order. Adhesion between the image display device and the half mirror can be performed using the above-mentioned adhesive layer, and it is preferable to use a highly transparent adhesive transfer tape.
  • the use of the mirror with an image display function is not particularly limited. For example, it can be used as a security mirror, a beauty salon or a barber mirror, and can display images such as character information, still images, and moving images.
  • the mirror with an image display function may be a vehicle rearview mirror, and may be used as a television, a personal computer, a smartphone, or a mobile phone.
  • the mirror with an image display function is particularly preferably used as a vehicle rearview mirror.
  • the mirror with an image display function may have a frame, a housing, a support arm for attaching to the vehicle body, and the like for use as a rearview mirror.
  • the vehicle image display function-equipped mirror may be formed for incorporation into a room mirror. In the vehicle-mounted image display function-equipped mirror having the above shape, it is possible to specify the vertical and horizontal directions during normal use.
  • Such a curved observation surface can be produced using a curved half mirror.
  • the curve may be in the vertical direction, the horizontal direction, or both the vertical direction and the horizontal direction.
  • the curvature may be a curvature radius of 500 mm to 3000 mm. More preferably, it is 1000 mm to 2500 mm.
  • the radius of curvature is the radius of the circumscribed circle when the circumscribed circle of the curved portion is assumed in the cross section.
  • Compound 2 was produced by the method described in JP-A-2005-99248.
  • the temporary support (100 mm ⁇ 150 mm) uses a PET film (Cosmo Shine A4100, thickness: 100 ⁇ m) manufactured by Toyobo Co., Ltd., and is rubbed (rayon cloth, pressure: 0.1 kgf (0.98 N), rotation speed: 1000 rpm. , Transport speed: 10 m / min, number of times: 1 reciprocation).
  • the coating liquid 1 was applied to the rubbed surface of the PET film using a wire bar, then dried and placed on a 30 ° C. hot plate.
  • UV irradiation was performed for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd. to fix the cholesteric liquid crystal phase to obtain a cholesteric liquid crystal layer having a thickness of 3.5 ⁇ m.
  • the same process is further repeated on the surface of the obtained layer using the coating liquid 2 and the coating liquid 3, and a circularly polarizing reflector A having three cholesteric liquid crystal layers (layer of coating liquid 2: 3.0 ⁇ m, coating liquid 3 Layer: 2.7 ⁇ m).
  • linearly polarized light reflecting plate was produced based on the method described in JP-T-9-506837.
  • 2,6-polyethylene naphthalate (PEN) and naphthalate 70 / terephthalate 30 copolyester (coPEN) were synthesized in a standard polyester resin synthesis kettle using ethylene glycol as the diol.
  • a single layer film of PEN and coPEN was extruded and then stretched at a stretch ratio of 5: 1 at about 150 ° C.
  • the refractive index of PEN with respect to the orientation axis was about 1.88
  • the refractive index with respect to the transverse axis was 1.64
  • the refractive index of the coPEN film was about 1.64.
  • the thickness of the alternating layer of PEN and coPEN was formed in the film thickness shown in Table 2 (1) by co-extrusion using a 50 slot supply block supplied with a standard extrusion die.
  • the PEN and coPEN layers having the thicknesses shown in Table 2 (2) to (5) were formed in order, and the formation of the layers (1) to (5) was further repeated to measure 50 layers each. 250 layers were laminated. Thereafter, the stretched film was thermally cured at about 230 ° C. for 30 seconds in an air oven to obtain a linearly polarized light reflector.
  • PET resin pellets having an intrinsic viscosity of 0.62 dl / g were dried under reduced pressure at 135 ° C. for 6 hours (1 Torr (133 Pa)), then supplied to an extruder and dissolved at 285 ° C.
  • This polymer is filtered with a filter material of stainless sintered body (nominal filtration accuracy 10 ⁇ m particles 95% cut), extruded into a sheet form from the die, and then applied to a casting drum having a surface temperature of 30 ° C. using an electrostatic application casting method. It was wound and solidified by cooling to make an unstretched film.
  • the unstretched film was guided to a tenter stretching machine, and the end of the film was guided by a clip while being guided by a clip, and stretched in the width direction.
  • it was processed at a temperature of 225 ° C. for 30 seconds, and further subjected to a relaxation treatment of 3% in the width direction, and uniaxially oriented light having a front phase difference shown in Table 3
  • the front phase difference was measured using an AxoScan manufactured by Axometrics.
  • UV irradiation was performed for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd. to form an antiglare layer having a thickness of 5 ⁇ m.
  • PETA (trade name PET-30): (Nippon Kayaku Co., Ltd.): 50 parts by mass KE-P30 (Nippon Shokubai Co., Ltd. amorphous silica particle seahoster, average primary particle size 300 nm): 10 parts by mass Irgacure 184 (BASF Japan shares) (Made by company): 2.0 parts by mass Butyl acetate: 50 parts by mass
  • the above coating solution was applied on a light-transmitting substrate having a front phase difference of 8000 nm using a wire bar, and then dried and placed on a hot plate at 30 ° C. placed.
  • UV irradiation was performed for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd. to form an antireflection layer having a thickness of 5.0 ⁇ m.
  • IP-15 described in Japanese Patent No. 5674729: IP-15: 5 parts by mass A-TMMT (Shin Nakamura Chemical Co., Ltd.): 92 parts by mass 1-butanol: 10 parts by mass Methyl ethyl ketone: 90 parts by mass Part
  • the coating solution was applied onto a light-transmitting substrate using a wire bar, dried, and placed on a 30 ° C. hot plate.
  • UV irradiation was carried out for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd., and the cholesteric liquid crystal phase was fixed to form an antistatic layer having a thickness of 5.0 ⁇ m.
  • a mold comprising a combination of a concave mold and a convex mold was prepared as a mold for producing a flat plate.
  • the temporary support (base film) of the transfer sheet was arranged so as to contact the inner surface of the mold, and vacuum transfer was performed to bring the transfer sheet into contact with the bottom surface of the concave mold.
  • a convex mold is combined with this concave mold, the mold is closed, and a molten resin made of PC (polycarbonate, Iupilon S3000) is brought into contact with the surface of the transfer sheet on the thermoplastic welding layer side in the formed space.
  • the molded resin layer was a flat plate of 150 mm ⁇ 100 mm ⁇ 3.0 mm.
  • the front phase difference distribution of the molded resin layer was adjusted by changing the injection speed and the cooling speed so as to take the values shown in Table 3.
  • the front phase difference distribution of the molded resin layer is the front phase difference of each sample obtained by equally dividing the molded resin layer produced in the same manner.
  • an optical adhesive film PDS1 manufactured by Panac was bonded to the surface of the molded resin layer of the obtained molded body with a SEAL type precision single-wafer bonding machine SE550aa (manufactured by Climb Products), and then the same apparatus was used.
  • a light transmissive substrate (first high Re retardation film: front phase difference 8000 nm) provided with the hard coat layer, antiglare layer, antireflection layer, and antistatic layer, respectively.
  • the half mirrors of Examples 12 to 15 were produced in the same manner as the production of the half mirror of Example 1, except that (2) was used.
  • the bonding to the adhesive film was performed so that the light-transmitting substrate side was in contact with the adhesive film.
  • the light transmissive substrate with the thermoplastic weld layer was disposed so that the light transmissive substrate was in contact with the inner surface of the convex mold.
  • the temporary transfer substrate (base film) of the same transfer sheet as the transfer sheet used in Example 1 is disposed so as to contact the inner surface of the mold, and vacuum transfer is performed to place the transfer sheet on the bottom surface of the concave mold. Contact.
  • Both molds are combined and closed, and a molten resin made of PC (polycarbonate, Iupilon S3000) is injected between the light-transmitting substrate in the mold and the transfer sheet (mold temperature 90 ° C., resin temperature : 300 ° C., pressure 100 MPa, time 30 seconds).
  • the molded body obtained by cooling to room temperature and opening the mold was taken out.
  • the temporary support was peeled off to obtain a half mirror.
  • the front phase difference distribution of the molded resin layer was adjusted to take the values shown in Table 3 as in Example 1.
  • An optical adhesive film PDS1 manufactured by Panac was bonded to the main surface on one side of the obtained molded resin layer using a SEAL type precision single wafer bonding machine SE550aa (manufactured by Climb Products). Subsequently, the same apparatus was used, and the circularly polarized light reflector B or the linearly polarized light reflector was bonded to the surface of the adhesive film. At this time, in the case of the circularly polarized light reflector B, the cholesteric liquid crystal layer side (the side opposite to the temporary support side) was bonded so as to contact the adhesive film, and the temporary support was peeled off.
  • An optical adhesive film PDS1 made by Panac is pasted on the surface of the molded resin layer opposite to the circularly polarized light reflector B or the linearly polarized light reflector with a SEAL type precision single wafer pasting machine SE550aa (Crim Products), and then the same.
  • a light-transmitting substrate first high Re phase difference film: front phase difference 8000 nm
  • the optical adhesive film PDS1 made by Panac is pasted on the surface of the molding resin layer opposite to the surface on which the quarter-wave plate is provided, using a SEAL type precision single wafer laminating machine SE550aa (manufactured by Climb Products). Then, using the same apparatus, a light transmissive substrate (first high Re retardation film: front retardation 8000 nm) was bonded.
  • the SEAL system precision sheet bonding machine SE550aa (manufactured by Climb Products) is used to bond the optical adhesive film PDS1 manufactured by Panac on the surface of the light-transmitting substrate, and then the same apparatus is used.
  • a circularly polarized light reflector A was bonded to the substrate. At this time, it bonded so that the cholesteric liquid crystal layer side (opposite side to a temporary support body side) might contact an adhesive film, and the temporary support body was peeled after that.
  • a quarter-wave plate with a support was bonded. At this time, it bonded so that the quarter wavelength plate side (opposite side to a temporary support body side) might contact an adhesive film, and the temporary support body was peeled after that.
  • SEAL type precision single wafer laminating machine SE550aa manufactured by Climb Products
  • optical adhesive film PDS1 made by Panac is used, and then the same device is used to apply circularly polarizing reflector A. did.
  • the cholesteric liquid crystal layer side opposite side to a temporary support body side
  • the temporary support body was peeled after that.
  • a heat sealant A-100 (made by DIC) was applied to the surface of a light-transmitting substrate (second high Re retardation film: front retardation 4000 nm) using a wire bar, and then dried to heat 3.0 ⁇ m.
  • a plastic welding layer was formed to obtain a molding sheet.
  • a mold comprising a combination of a concave mold and a convex mold was prepared as a mold for producing a flat plate.
  • the light-transmitting substrate of the molding sheet was arranged in such a direction as to contact the inner surface of the mold, and vacuum suction was performed to bring the molding sheet into contact with the bottom surface of the concave mold.
  • a convex mold is combined with this concave mold, the mold is closed, and a molten resin made of PC (polycarbonate, Iupilon S3000) is brought into contact with the surface of the transfer sheet on the thermoplastic welding layer side in the formed space. Then, it was poured into a mold and molded (mold temperature 90 ° C., resin temperature: 300 ° C., pressure 100 MPa, time 30 seconds). The molded body obtained by cooling to room temperature and opening the mold was taken out. The molded resin layer in the obtained molded body was a flat plate of 150 mm ⁇ 100 mm ⁇ 3.0 mm. The front phase difference distribution of the molded resin layer at this time was prepared by adjusting the injection speed and the cooling speed so as to take the values shown in the table.
  • PC polycarbonate, Iupilon S3000
  • an optical adhesive film PDS1 made by Panac was pasted on the light-transmitting base material (second high Re retardation film) with a SEAL-type precision single-wafer laminating machine SE550aa (Crim Products), and then the same.
  • the circularly polarized light reflector B was bonded.
  • the cholesteric liquid crystal layer side (the side opposite to the temporary support side) was bonded so as to contact the adhesive film, and the temporary support was peeled off.
  • the optical adhesive film PDS1 made by Panac is pasted on the surface of the molded resin layer opposite to the circularly polarizing reflector B using a SEAL precision single-wafer laminating machine SE550aa (manufactured by Climb Products), and then the same apparatus is used.
  • the direction of the slow axis of the light transmissive substrate (first high Re phase difference film, front phase difference 4000 nm) is the angle shown in Table 4 with respect to the direction of the slow axis of the second high Re phase difference film.
  • the half mirrors of Example 19 and Reference Example 4 were obtained.
  • Example 7 the mold for producing a flat plate comprising a combination of a concave mold and a convex mold was closed, and the molten resin shown in Table 4 was injected and molded (mold temperature 90 ° C., resin temperature: 300 ° C., pressure 100 MPa. , Time 30 seconds)).
  • the molded resin layer flat plate of 150 mm ⁇ 100 mm ⁇ 3 mm obtained by cooling to room temperature and opening the mold was taken out.
  • the molten resin PC is Iupilon S3000.
  • the front phase difference distribution of the molded resin layer was adjusted to take the values shown in the table in the same manner as in Example 1.
  • An optical adhesive film PDS1 manufactured by Panac was bonded to the main surface on one side of the obtained molded resin layer using a SEAL type precision single wafer bonding machine SE550aa (manufactured by Climb Products).
  • a light-transmitting substrate second high Re retardation film, front retardation 4000 nm
  • SEAL type precision single wafer bonding machine SE550aa Climb
  • An optical adhesive film PDS1 manufactured by Panac Co., Ltd. was pasted with a product manufactured by Products Co., Ltd., and then the circularly polarizing reflector B was pasted using the same apparatus.
  • the circularly polarized light reflector B the cholesteric liquid crystal layer side (the side opposite to the temporary support side) was bonded so as to contact the adhesive film, and the temporary support was peeled off.
  • An optical adhesive film PDS1 manufactured by Panac was bonded to the surface of the molded resin layer opposite to the circularly polarizing reflector B using a SEAL type precision single wafer bonding machine SE550aa (manufactured by Climb Products), and then the same apparatus was used.
  • the light transmissive substrate (first high Re phase difference film, front phase difference 4000 nm) is set so that the slow axis direction forms an angle of 0 ° with the slow axis direction of the second high Re phase difference film.
  • the half mirror of Example 20 was obtained.
  • Tables 3 and 4 show the angles formed by the slow axis of the light-transmitting substrate and the polarization axis of the viewing-side polarizer of the image display device between 0 ° and 90 ° while maintaining the above parallel state.
  • the position was set as follows. When the white image was displayed on the image display device, the image was observed from the observation surface with polarized sunglasses, and the presence and extent of color unevenness was confirmed. Evaluation was made according to the following criteria. The results are shown in Tables 3 and 4. None: When observed from the front, color unevenness does not occur and visibility is not a problem. Existence: Color unevenness is observed when observed from the front.
  • Table 3 shows the angles formed by the slow axis of the light-transmitting substrate and the polarization axis of the viewing-side polarizer of the image display device in the range of 0 ° to 90 °, as in the case of the color unevenness evaluation of the image.
  • the position was set as follows.
  • the mirror reflection image when the image display device was turned off was observed from the observation surface with polarized sunglasses, and the presence and extent of color unevenness was confirmed. Evaluation was made according to the following criteria. The results are shown in Tables 3 and 4. None: When observed from the front, color unevenness does not occur and visibility is not a problem. Existence: Color unevenness is observed when observed from the front.
  • Linear polarization transmittance The linearly polarized light transmittance was measured using an ultraviolet-visible near-infrared spectrophotometer V-670 manufactured by JASCO Corporation. The transmittance for linearly polarized light was measured by placing a linearly polarizing plate on the light source side of the spectrophotometer so that the polarization transmission axis and the slow axis of the quarter wavelength plate were 45 °. The average transmittance with respect to the linearly polarized light having a wavelength of 400 nm to 700 nm of the natural light transmittance thus obtained was calculated, and 80% or more was judged good and less than 80% was judged as bad. The results are shown in Tables 3 and 4.

Landscapes

  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Optics & Photonics (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mathematical Physics (AREA)
  • Multimedia (AREA)
  • Mechanical Engineering (AREA)
  • Theoretical Computer Science (AREA)
  • Polarising Elements (AREA)

Abstract

Provided are: a half mirror configured to have a reflective polarizing plate on a resin layer formed by processes including heating and pressing, and capable of presenting a uniform mirror reflection image; and a mirror with image displaying function displaying an image that presents a uniform mirror reflection image and a bright and uniform image. The half mirror includes an observation surface, a molded resin layer, and a reflective polarizing plate in this order and includes at least one high-Re phase difference film between the observation surface and the reflective polarizing plate, the sum of the front phase differences of the high-Re phase difference film being 3000 nm or greater. The half mirror includes a first high-Re phase difference film between the observation surface and the molded resin layer as the high-Re phase difference film.

Description

ハーフミラーおよび画像表示機能付きミラーHalf mirror and mirror with image display function
　本発明は、ハーフミラー、およびハーフミラーを含む画像表示機能付きミラーに関する。 The present invention relates to a half mirror and a mirror with an image display function including the half mirror.
　車両用のミラーに車載カメラで撮像された画像などの画像の表示も可能とした車両用画像表示機能付きミラーについては、例えば、特許文献１に記載がある。特許文献１で開示される車両用画像表示機能付きミラーでは、車両用ミラーのハウジングの内部に液晶表示装置を設け、車両用ミラーの前面に設けられたハーフミラーを介して画像を表示することにより、ミラーでの画像表示を実現している。 For example, Patent Document 1 describes a mirror with a vehicle image display function that can display an image such as an image captured by a vehicle-mounted camera on a vehicle mirror. In the mirror with a vehicle image display function disclosed in Patent Document 1, a liquid crystal display device is provided inside the housing of the vehicle mirror, and an image is displayed through a half mirror provided on the front surface of the vehicle mirror. The image display on the mirror is realized.
　表示機能付きミラーとしては、特許文献２においては、インテリア、化粧用、防犯用、および、安全用の鏡に適用される情報表示機能付鏡に関する開示があり、ハーフミラーとして偏光反射板を利用することが記載されている。
　ミラーの製造方法としては、特許文献３に記載されているように、射出成形で得られる樹脂層に反射フィルムを熱圧着する方法が知られている。 As a mirror with a display function, Patent Document 2 discloses a mirror with an information display function applied to interior, cosmetic, crime prevention, and safety mirrors, and a polarizing reflector is used as a half mirror. It is described.
As a method for manufacturing a mirror, as described in Patent Document 3, a method in which a reflective film is thermocompression bonded to a resin layer obtained by injection molding is known.
特開２０１４－２０１１４６号公報JP 2014-2011146 A 特開２０１１－４５４２７号公報JP 2011-45427 A 特開２００４－２８６９４３号公報Japanese Patent Application Laid-Open No. 2004-286943
　特許文献１に記載の車両用画像表示機能付きミラーにおけるハーフミラーとして、金属蒸着ミラー等を用いると、可視光の透過率が通常３０％～７０％程度となり、画像がハーフミラーを有していないものよりも暗くなるという問題が潜在的にある。
　一方、特許文献２に記載のような偏光反射板を利用すると光のロスをなくすことができる。そこで、本発明者らは、特許文献３に記載のような射出成形により得られた樹脂層の表面に偏光反射板を設けたハーフミラーを作製した。しかし、得られたハーフミラーのミラー反射像を偏光サングラスを介して観察したところ、明暗ムラが確認された。また、このハーフミラーを用いて作製した画像表示機能付きミラーの画像についても、偏光サングラスを介して観察したところ、明暗ムラまたは色ムラ（虹色など）が確認された。 When a metal-deposited mirror or the like is used as a half mirror in the vehicle image display function mirror described in Patent Document 1, the visible light transmittance is usually about 30% to 70%, and the image does not have a half mirror. There is a potential problem of becoming darker than things.
On the other hand, when a polarizing reflector as described in Patent Document 2 is used, light loss can be eliminated. Therefore, the present inventors produced a half mirror in which a polarizing reflector is provided on the surface of a resin layer obtained by injection molding as described in Patent Document 3. However, when the mirror reflection image of the obtained half mirror was observed through polarized sunglasses, uneven brightness was confirmed. Moreover, when the image of the mirror with an image display function produced using this half mirror was also observed through polarized sunglasses, light / dark unevenness or color unevenness (rainbow color, etc.) was confirmed.
　本発明は、加熱および加圧を含む加工で成形された樹脂層上に偏光反射板を有する構成のハーフミラーとして、ムラのないミラー反射像を与えるハーフミラーを提供することを課題とする。本発明はさらに、加熱および加圧を含む加工で成形された樹脂層上に偏光反射板を有する構成のハーフミラーを含む画像表示機能付きミラーとして、ムラのないミラー反射像とともに、明るく、ムラのない画像を与える画像表示機能付きミラーを提供することを課題とする。 An object of the present invention is to provide a half mirror that gives a mirror reflection image without unevenness as a half mirror having a polarizing reflector on a resin layer formed by processing including heating and pressing. Furthermore, the present invention provides a mirror with an image display function including a half mirror having a polarizing reflector on a resin layer formed by processing including heating and pressurization, as well as a non-uniform mirror reflection image, and a bright, non-uniformity. It is an object of the present invention to provide a mirror with an image display function that gives a non-image.
　本発明者らは、上記課題の解決のため鋭意検討し、本発明を完成させた。
　本発明は以下の［１］～［１９］を提供する。
［１］観察面、成形樹脂層、および偏光反射板をこの順で含み、
上記観察面と上記偏光反射板との間に高Ｒｅ位相差膜を少なくとも１つ含み、上記高Ｒｅ位相差膜の正面位相差の合計が３０００ｎｍ以上であり、
上記高Ｒｅ位相差膜として第１の高Ｒｅ位相差膜を、上記観察面と上記成形樹脂層との間に、含むハーフミラー。
［２］上記成形樹脂層の正面位相差分布が１００ｎｍ以上である［１］に記載のハーフミラー。
［３］上記高Ｒｅ位相差膜の正面位相差の合計が５０００ｎｍ以上である［１］または［２］に記載のハーフミラー。 The present inventors diligently studied to solve the above problems and completed the present invention.
The present invention provides the following [1] to [19].
[1] An observation surface, a molded resin layer, and a polarizing reflector are included in this order,
Including at least one high Re retardation film between the observation surface and the polarizing reflector, the total front retardation of the high Re retardation film is 3000 nm or more,
A half mirror including a first high Re retardation film as the high Re retardation film between the observation surface and the molding resin layer.
[2] The half mirror according to [1], wherein the front phase difference distribution of the molded resin layer is 100 nm or more.
[3] The half mirror according to [1] or [2], wherein the total front retardation of the high Re retardation film is 5000 nm or more.
［４］上記第１の高Ｒｅ位相差膜の正面位相差が３０００ｎｍ以上である［１］～［３］のいずれかに記載のハーフミラー。
［５］上記高Ｒｅ位相差膜として上記第１の高Ｒｅ位相差膜のみを含む［１］～［４］のいずれかに記載のハーフミラー。
［６］上記高Ｒｅ位相差膜として第２の高Ｒｅ位相差膜を、上記成形樹脂層と上記偏光反射板との間に、さらに含む［１］～［４］のいずれかに記載のハーフミラー。
［７］上記第１の高Ｒｅ位相差膜の遅相軸の方向と、上記第２の高Ｒｅ位相差膜の遅相軸の方向と、が同じである［６］に記載のハーフミラー。
［８］上記第２の高Ｒｅ位相差膜と上記成形樹脂層との間に接着層または熱可塑性溶着層を含む［６］または［７］に記載のハーフミラー。 [4] The half mirror according to any one of [1] to [3], wherein the front phase difference of the first high Re retardation film is 3000 nm or more.
[5] The half mirror according to any one of [1] to [4], including only the first high Re retardation film as the high Re retardation film.
[6] The half according to any one of [1] to [4], further including a second high Re retardation film as the high Re retardation film between the molding resin layer and the polarizing reflector. mirror.
[7] The half mirror according to [6], wherein the direction of the slow axis of the first high Re retardation film is the same as the direction of the slow axis of the second high Re retardation film.
[8] The half mirror according to [6] or [7], including an adhesive layer or a thermoplastic weld layer between the second high Re retardation film and the molded resin layer.
［９］上記成形樹脂層が、ポリカーボネート、ポリ（メタ）アクリレート、ポリエステル、およびシクロオレフィンポリマーからなる群より選択されるいずれか1つ以上のポリマーを含む［１］～［８］のいずれかに記載のハーフミラー。
［１０］上記偏光反射板が円偏光反射層である［１］～［９］のいずれかに記載のハーフミラー。
［１１］上記円偏光反射層がコレステリック液晶層を含む［１０］に記載のハーフミラー。
［１２］上記円偏光反射層が３層以上のコレステリック液晶層を含む［１１］に記載のハーフミラー。
［１３］１／４波長板をさらに含み、
上記成形樹脂層、上記偏光反射板、および上記１／４波長板をこの順に含む［１０］～［１２］のいずれかに記載のハーフミラー。
［１４］上記偏光反射板と上記１／４波長板とが互いに直接接している［１３］に記載のハーフミラー。 [9] Any one of [1] to [8], wherein the molded resin layer includes one or more polymers selected from the group consisting of polycarbonate, poly (meth) acrylate, polyester, and cycloolefin polymer. Half mirror described.
[10] The half mirror according to any one of [1] to [9], wherein the polarizing reflector is a circularly polarizing reflecting layer.
[11] The half mirror according to [10], wherein the circularly polarized light reflecting layer includes a cholesteric liquid crystal layer.
[12] The half mirror according to [11], wherein the circularly polarized light reflection layer includes three or more cholesteric liquid crystal layers.
[13] Further includes a quarter wave plate,
The half mirror according to any one of [10] to [12], including the molded resin layer, the polarizing reflector, and the quarter-wave plate in this order.
[14] The half mirror according to [13], wherein the polarizing reflector and the quarter-wave plate are in direct contact with each other.
［１５］上記成形樹脂層と上記偏光反射板との間に接着層または熱可塑性溶着層を含む［１］～［１４］のいずれかに記載のハーフミラー。
［１６］上記第１の高Ｒｅ位相差膜と上記成形樹脂層との間に接着層または熱可塑性溶着層を含む［１］～［１５］のいずれかに記載のハーフミラー。
［１７］［１］～［１６］のいずれかに記載のハーフミラー、および画像表示装置を含み、
上記観察面、上記成形樹脂層、上記偏光反射板、および上記画像表示装置がこの順で配置されている画像表示機能付きミラー。
［１８］上記画像表示装置は直線偏光を出射して画像を形成し、
上記画像表示装置が、連続的な発光スペクトルを与えるバックライトを有し、
上記第１の高Ｒｅ位相差膜の遅相軸が上記直線偏光の偏光方向と３０°～６０°の角度をなしている［１７］に記載の画像表示機能付きミラー。
［１９］上記画像表示装置が液晶表示装置であり、上記バックライトが白色ＬＥＤである［１８］に記載の画像表示機能付きミラー。 [15] The half mirror according to any one of [1] to [14], which includes an adhesive layer or a thermoplastic weld layer between the molded resin layer and the polarizing reflector.
[16] The half mirror according to any one of [1] to [15], which includes an adhesive layer or a thermoplastic weld layer between the first high Re retardation film and the molded resin layer.
[17] The half mirror according to any one of [1] to [16] and an image display device,
A mirror with an image display function in which the observation surface, the molded resin layer, the polarizing reflector, and the image display device are arranged in this order.
[18] The image display device emits linearly polarized light to form an image,
The image display device has a backlight that gives a continuous emission spectrum,
The mirror with an image display function according to [17], wherein a slow axis of the first high Re retardation film forms an angle of 30 ° to 60 ° with a polarization direction of the linearly polarized light.
[19] The mirror with an image display function according to [18], wherein the image display device is a liquid crystal display device, and the backlight is a white LED.
　本発明により、加熱および加圧を含む加工で成形された樹脂層上に偏光反射板を有する構成のハーフミラーとして、ムラのないミラー反射像を与えるハーフミラーを提供することができる。また、加熱および加圧を含む加工で成形された樹脂層上に偏光反射板を有する構成のハーフミラーを含む画像表示機能付きミラーとして、ムラのないミラー反射像とともに、明るく、ムラのない画像を与える画像表示機能付きミラーを提供することができる。 According to the present invention, it is possible to provide a half mirror that gives a mirror reflection image without unevenness as a half mirror having a polarizing reflector on a resin layer formed by processing including heating and pressing. Moreover, as a mirror with an image display function including a half mirror having a polarizing reflector on a resin layer formed by processing including heating and pressurization, a bright and non-uniform image is displayed together with a non-uniform mirror reflection image. A mirror with an image display function can be provided.
　以下、本発明を詳細に説明する。
　本明細書において「～」とはその前後に記載される数値を下限値および上限値として含む意味で使用される。
　本明細書において、例えば、「４５°」、「平行」、「垂直」あるいは「直交」等の角度は、特に記載がなければ、厳密な角度との差異が５°未満の範囲内であることを意味する。厳密な角度との差異は、４°未満であることが好ましく、３°未満であることがより好ましい。
　本明細書において、「（メタ）アクリレート」との記載は、「アクリレートおよびメタクリレートのいずれか一方または双方」の意味を表す。「ポリ（メタ）アクリレート」等も同様である。 Hereinafter, the present invention will be described in detail.
In the present specification, “to” is used in the sense of including the numerical values described before and after it as lower and upper limits.
In this specification, for example, an angle such as “45 °”, “parallel”, “vertical” or “orthogonal” is within a range where the difference from the exact angle is less than 5 ° unless otherwise specified. Means. The difference from the exact angle is preferably less than 4 °, more preferably less than 3 °.
In the present specification, the description of “(meth) acrylate” represents the meaning of “any one or both of acrylate and methacrylate”. The same applies to “poly (meth) acrylate” and the like.
　本明細書において、円偏光につき「選択的」というときは、右円偏光成分または左円偏光成分のいずれかの光量が、他方の円偏光成分よりも多いことを意味する。具体的には「選択的」というとき、光の円偏光度は、０．３以上であることが好ましく、０．６以上がより好ましく、０．８以上がさらに好ましい。実質的に１．０であることが特に好ましい。ここで、円偏光度とは、光の右円偏光成分の強度をＩR、左円偏光成分の強度をＩLとしたとき、｜ＩR－ＩL｜／（ＩR＋ＩL）で表される値である。 In this specification, “selective” for circularly polarized light means that either the right circularly polarized light component or the left circularly polarized light component has more light than the other circularly polarized light component. Specifically, when referred to as “selective”, the degree of circular polarization of light is preferably 0.3 or more, more preferably 0.6 or more, and even more preferably 0.8 or more. It is particularly preferred that it is substantially 1.0. Table In / (I R + I L) | Here, the degree of circular polarization, the intensity of the right circularly polarized light component of the light I R, when the strength of the left-handed circularly polarized light component and I L, | I R -I L Is the value to be
　本明細書において、円偏光につき「センス」というときは、右円偏光であるか、または左円偏光であるかを意味する。円偏光のセンスは、光が手前に向かって進んでくるように眺めた場合に電場ベクトルの先端が時間の増加に従って時計回りに回る場合が右円偏光であり、反時計回りに回る場合が左円偏光であるとして定義される。 In this specification, “sense” for circularly polarized light means right circularly polarized light or left circularly polarized light. The sense of circularly polarized light is right-handed circularly polarized light when the electric field vector tip turns clockwise as time increases when viewed as the light travels toward you, and left when it turns counterclockwise. Defined as being circularly polarized.
　本明細書においては、コレステリック液晶の螺旋の捩れ方向について「センス」との用語を用いることもある。コレステリック液晶の螺旋の捩れ方向（センス）が右の場合は右円偏光を反射し、左円偏光を透過する。コレステリック液晶の螺旋のセンスが左の場合は左円偏光を反射し、右円偏光を透過する。 In this specification, the term “sense” is sometimes used for the twist direction of the spiral of the cholesteric liquid crystal. When the twist direction (sense) of the spiral of the cholesteric liquid crystal is right, the right circular polarized light is reflected and the left circular polarized light is transmitted. When the spiral sense of the cholesteric liquid crystal is on the left, it reflects left circularly polarized light and transmits right circularly polarized light.
　本明細書において、正面位相差は、Ａｘｏｍｅｔｒｉｃｓ社製のＡｘｏＳｃａｎを用いて測定した値である。測定波長は特に言及のないときは５５０ｎｍとする。正面位相差はＫＯＢＲＡ　２１ＡＤＨまたはＷＲ（王子計測機器株式会社製）においてコレステリック液晶層の選択反射の中心波長などの可視光波長域内の波長の光をフィルム法線方向に入射させて測定した値を用いることもできる。測定波長の選択にあたっては、波長選択フィルターをマニュアルで交換するか、または測定値をプログラム等で変換して測定することができる。本明細書において、正面位相差を「Ｒｅ」ということもある。 In the present specification, the front phase difference is a value measured using an AxoScan manufactured by Axometrics. The measurement wavelength is 550 nm unless otherwise specified. The front phase difference is a value measured by making light in a wavelength range of visible light such as the central wavelength of selective reflection of the cholesteric liquid crystal layer incident in the normal direction of the film in KOBRA 21ADH or WR (manufactured by Oji Scientific Instruments). You can also When selecting the measurement wavelength, the wavelength selection filter can be exchanged manually, or the measurement value can be converted by a program or the like. In the present specification, the front phase difference is sometimes referred to as “Re”.
　本明細書において、「ミラー反射像」というときは、ハーフミラーからの反射に基づいて観測される像を意味する。ミラー反射像は観察面で観測されるものであればよい。本明細書において、「画像」というときは、画像表示装置の画像、または画像表示装置の画像表示部で画像が表示されているときに、画像表示機能付きミラーで観察される画像表示装置の画像由来の像を意味する。 In this specification, “mirror reflection image” means an image observed based on reflection from a half mirror. The mirror reflection image only needs to be observed on the observation surface. In this specification, the term “image” refers to an image of an image display device or an image of an image display device that is observed by a mirror with an image display function when the image is displayed on an image display unit of the image display device. It means the image of origin.
＜＜ハーフミラー＞＞
　本明細書において、ハーフミラーは、鏡として、光を反射する機能を有するとともに、所望の波長の光の少なくとも一部を透過する機能を有するものを意味する。
　本発明のハーフミラーは、観察面、成形樹脂層、および偏光反射板をこの順で含み、さらに高Ｒｅ位相差膜を含む。ハーフミラーは光学機能層、接着層、熱可塑性溶着層などの他の層を含んでいてもよい。 << Half Mirror >>
In this specification, a half mirror means a mirror having a function of reflecting light and a function of transmitting at least part of light having a desired wavelength.
The half mirror of the present invention includes an observation surface, a molded resin layer, and a polarizing reflector in this order, and further includes a high Re retardation film. The half mirror may include other layers such as an optical functional layer, an adhesive layer, and a thermoplastic welding layer.
　本発明のハーフミラーは、偏光反射板から見て成形樹脂層側である最外面を観察面としていればよい。なお、本明細書において、観察面は、ミラー反射像を観察する側の面であって、ハーフミラーの反射面を意味する。
　ハーフミラーの形状は用途に応じたものであればよく、特に限定されず、板状またはフィルム状であることが好ましい。ハーフミラーは曲面を有していてもよい。すなわち、ハーフミラーは平坦であってもよく、湾曲していてもよい。特に湾曲した形状は、球面以外に必要な光学性能に応じて多項式非球面やゼルニケ多項式面等の自由曲面で設計することができる。車両用ミラー用途などにおいては、観察面が凸曲面である形状が好ましい。 The half mirror of this invention should just use the outermost surface which is a shaping | molding resin layer side seeing from a polarizing reflective plate as an observation surface. In the present specification, the observation surface is a surface on the side where the mirror reflection image is observed, and means the reflection surface of the half mirror.
The shape of a half mirror should just be a thing according to a use, and is not specifically limited, It is preferable that it is plate shape or film shape. The half mirror may have a curved surface. That is, the half mirror may be flat or curved. In particular, a curved shape can be designed with a free-form surface such as a polynomial aspherical surface or a Zernike polynomial surface according to the required optical performance other than the spherical surface. In a vehicle mirror application, a shape in which the observation surface is a convex curved surface is preferable.
＜成形樹脂層（溶融樹脂）＞
　本明細書において、成形樹脂層は加熱および加圧を含む加工で成形された樹脂層を意味する。成形樹脂層は射出成形で得られたものであることが好ましい。成形樹脂層の製法については後述する。
　成形樹脂層の形状は特に限定されず、板状またはフィルム状であることが好ましい。成形樹脂層は曲面を有していてもよい。すなわち、成形樹脂層は平坦であってもよく、湾曲していてもよい。 <Molded resin layer (molten resin)>
In the present specification, the molded resin layer means a resin layer molded by processing including heating and pressing. The molded resin layer is preferably obtained by injection molding. The method for producing the molded resin layer will be described later.
The shape of the molded resin layer is not particularly limited, and is preferably a plate shape or a film shape. The molded resin layer may have a curved surface. That is, the molded resin layer may be flat or curved.
　本発明のハーフミラーにおいて、成形樹脂層としては可視光領域で透明であるものが用いられる。ここで、可視光領域で透明とは、可視光領域における光線透過率が、８０％以上、好ましくは８５％以上であることをいう。透明の尺度として用いられる光線透過率は、ＪＩＳ　Ａ５７５９に記載された方法で求められる。すなわち分光光度計にて、波長３８０ｎｍ～７８０ｎｍの透過率を測定し、ＣＩＥ（国際照明委員会）昼光Ｄ６５の分光分布、ＣＩＥ　明順応標準比視感度の波長分布および波長間隔から得られる重価係数を乗じて加重平均することによって光線透過率を求める。 In the half mirror of the present invention, a transparent resin layer in the visible light region is used as the molded resin layer. Here, being transparent in the visible light region means that the light transmittance in the visible light region is 80% or more, preferably 85% or more. The light transmittance used as a scale of transparency is obtained by the method described in JIS A5759. That is, the transmittance obtained at a wavelength of 380 nm to 780 nm is measured with a spectrophotometer, and the weight obtained from the spectral distribution of CIE (International Commission on Illumination) daylight D65, the wavelength distribution of CIE light adaptation standard relative luminous sensitivity, and the wavelength interval. The light transmittance is obtained by multiplying the coefficient and performing a weighted average.
　成形樹脂層は加熱および加圧を含む加工によって、複屈折性が不均一となりやすい。例えば、成形樹脂層の正面位相差の分布は５０ｎｍ以上が好ましく、１００ｎｍ以上が特に好ましい。また、成形樹脂層の正面位相差の分布は最大で５００ｎｍ程度が好ましい。ここで、正面位相差の分布は、実施例に示すように、９等分した測定対象の正面位相差を測定し、最大値と最小値との差を算出することにより求める。 The molded resin layer is likely to have non-uniform birefringence due to processing including heating and pressing. For example, the front retardation distribution of the molded resin layer is preferably 50 nm or more, and particularly preferably 100 nm or more. The distribution of the front retardation of the molded resin layer is preferably about 500 nm at the maximum. Here, as shown in the embodiment, the distribution of the front phase difference is obtained by measuring the front phase difference of the measurement object divided into nine equal parts and calculating the difference between the maximum value and the minimum value.
　成形樹脂層の厚みは、１００μｍ～１０ｍｍ程度であればよく、好ましくは２００μｍ～５．０ｍｍであり、より好ましくは５００μｍ～４．０ｍｍであり、さらに好ましくは１．０ｍｍ～３．０ｍｍである。 The thickness of the molded resin layer may be about 100 μm to 10 mm, preferably 200 μm to 5.0 mm, more preferably 500 μm to 4.0 mm, and still more preferably 1.0 mm to 3.0 mm.
　成形樹脂層の形成のための材料としては、熱可塑性樹脂および熱硬化性樹脂が挙げられる。熱硬化性樹脂である場合、成形樹脂層の形成のための材料は、重合性基を有するモノマーを含んでいてもよい。成形樹脂層の形成のための材料としては、熱可塑性樹脂が好ましい。成形樹脂層の形成のための材料は、すなわち、成形樹脂層の製造において、例えば金型に射出される樹脂であることから、一般的に射出成形に使用される樹脂であることが好ましい。成形樹脂層の形成のための材料は成形樹脂層の形成の際、融点以上に加熱された溶融樹脂として用いられる。 Examples of the material for forming the molded resin layer include thermoplastic resins and thermosetting resins. In the case of a thermosetting resin, the material for forming the molded resin layer may contain a monomer having a polymerizable group. As a material for forming the molded resin layer, a thermoplastic resin is preferable. The material for forming the molded resin layer is a resin that is generally used for injection molding because it is, for example, a resin that is injected into a mold in the manufacture of the molded resin layer. The material for forming the molded resin layer is used as a molten resin heated to the melting point or higher when forming the molded resin layer.
　熱可塑性樹脂の例としては、ポリカーボネート（ＰＣ）、ポリ（メタ）アクリレート、ポリエチレンテレフタレート（ＰＥＴ）などのポリエステル、シクロオレフィンポリマー（ＣＯＰ）を挙げることができる。熱硬化性樹脂の例としては、フェノール樹脂、エポキシ樹脂、メラミン樹脂、ユリア樹脂、不飽和ポリエステル樹脂、ジアリルフタレート樹脂、ポリウレタン樹脂、シリコーン樹脂を挙げることができる。 Examples of the thermoplastic resin include polycarbonate (PC), poly (meth) acrylate, polyester such as polyethylene terephthalate (PET), and cycloolefin polymer (COP). Examples of thermosetting resins include phenolic resins, epoxy resins, melamine resins, urea resins, unsaturated polyester resins, diallyl phthalate resins, polyurethane resins, and silicone resins.
　成形樹脂層の形成のための材料としては、これらのうち、ポリカーボネート、ポリ（メタ）アクリレート、ポリエステル、シクロオレフィンポリマーが好ましく、ポリ（メタ）アクリレートまたはポリカーボネートがより好ましく、ポリカーボネートがさらに好ましい。
　市販品の熱可塑性樹脂の例としては、ユーピロンＳ３０００　ｌ（ポリカーボネート、三菱エンジニアリングプラスチック株式会社製）、ノバレックス７０２２－ｌ（ポリカーボネート、三菱エンジニアリングプラスチック株式会社製）、スミペックス　ＭＧ５（ポリ（メタ）アクリレート、住友化学株式会社製）、ＰＥＴＧ　Ｋ２０１２（ポリエチレンテレフタレート、イーストマンケミカル社製）、ゼオネックス　Ｅ４８Ｒ（シクロオレフィンポリマー、日本ゼオン株式会社製）、パンライト　Ｌ－１２５０Ｚ１００（ポリカーボネート、帝人株式会社）、ＤＵＲＢＩＯ　Ｔ７４４ＯＩＲ（ポリカーボネート、三菱化学株式会社製）等を用いることができる。 Of these, polycarbonate, poly (meth) acrylate, polyester, and cycloolefin polymer are preferable as the material for forming the molded resin layer, poly (meth) acrylate or polycarbonate is more preferable, and polycarbonate is more preferable.
Examples of commercially available thermoplastic resins include Iupilon S3000 l (polycarbonate, manufactured by Mitsubishi Engineering Plastics), Novalex 7022-l (polycarbonate, manufactured by Mitsubishi Engineering Plastics), Sumipex MG5 (poly (meth) acrylate, Sumitomo Chemical Co., Ltd.), PETG K2012 (polyethylene terephthalate, Eastman Chemical Co., Ltd.), Zeonex E48R (cycloolefin polymer, Nippon Zeon Co., Ltd.), Panlite L-1250Z100 (Polycarbonate, Teijin Ltd.), DURBIO T744OIR ( Polycarbonate, manufactured by Mitsubishi Chemical Corporation) can be used.
＜偏光反射板：直線偏光反射層＞
　偏光反射板としては、直線偏光反射層および円偏光反射層が挙げられる。
　直線偏光反射層としては、例えば（ｉ）多層構造の直線偏光反射板、（ｉｉ）複屈折の異なる薄膜を積層した偏光子、（ｉｉｉ）ワイヤーグリッド偏光子、（ｉｖ）偏光プリズム、（ｖ）散乱異方性型偏光板などが挙げられる。 <Polarized reflector: linearly polarized reflective layer>
Examples of the polarizing reflector include a linearly polarized light reflecting layer and a circularly polarized light reflecting layer.
Examples of the linearly polarized light reflecting layer include (i) a linearly polarized light reflecting plate having a multilayer structure, (ii) a polarizer in which thin films having different birefringence are laminated, (iii) a wire grid polarizer, (iv) a polarizing prism, (v) Examples include a scattering anisotropic polarizing plate.
　（ｉ）多層構造の直線偏光反射板としては、互いに屈折率の異なる誘電体薄膜を複数積層してなるものが挙げられる。波長選択反射膜とするためには、高屈折率の誘電体薄膜と低屈折率の誘電体薄膜とを交互に複数層積層することが好ましいが、２種以上に限定されず、それ以上の種類であってもよい。積層数は、２層～２０層が好ましく、２層～１２層がより好ましく、４層～１０層が更に好ましく、６層～８層が特に好ましい。積層数を２０層以下とすることで、多層蒸着を原因とする生産効率性の低下を防止することができる。 (I) Examples of the linearly polarized light reflecting plate having a multilayer structure include those obtained by laminating a plurality of dielectric thin films having different refractive indexes. In order to obtain a wavelength selective reflection film, it is preferable to alternately stack a plurality of high-refractive-index dielectric thin films and low-refractive-index dielectric thin films. It may be. The number of laminated layers is preferably 2 to 20 layers, more preferably 2 to 12 layers, still more preferably 4 to 10 layers, and particularly preferably 6 to 8 layers. By making the number of layers 20 or less, it is possible to prevent a decrease in production efficiency due to multilayer deposition.
　誘電体薄膜の積層順については、特に制限はなく、目的に応じて適宜選択することができ、例えば、隣接する膜の屈折率が高い場合にはそれより低い屈折率の膜を最初に積層する。その逆に、隣接する層の屈折率が低い場合にはそれより高い屈折率の膜を最初に積層する。屈折率の高低の境目の目安は１．８である。なお、屈折率の高低は絶対的なものではなく、高屈折率の材料の中でも、相対的に屈折率の高いものと低いものとが存在してもよく、これらを交互に使用してもよい。 The order of stacking the dielectric thin films is not particularly limited and can be appropriately selected depending on the purpose. For example, when the refractive index of an adjacent film is high, a film having a lower refractive index is first stacked. . Conversely, if the refractive index of the adjacent layer is low, a film having a higher refractive index is first deposited. The standard for the boundary of the refractive index is 1.8. Note that the refractive index level is not absolute, and among the high refractive index materials, there may be a relatively high refractive index and a low refractive index, or these may be used alternately. .
　高屈折率の誘電体薄膜の材料としては、例えば、Ｓｂ2Ｏ3、Ｓｂ2Ｓ3、Ｂｉ2Ｏ3、ＣｅＯ2、ＣｅＦ3、ＨｆＯ2、Ｌａ2Ｏ3、Ｎｄ2Ｏ3、Ｐｒ6Ｏ11、Ｓｃ2Ｏ3、ＳｉＯ、Ｔａ2Ｏ5、ＴｉＯ2、ＴｌＣｌ、Ｙ2Ｏ3、ＺｎＳｅ、ＺｎＳ、ＺｒＯ2、などが挙げられる。これらの中でも、Ｂｉ2Ｏ3、ＣｅＯ2、ＣｅＦ3、ＨｆＯ2、ＳｉＯ、Ｔａ2Ｏ5、ＴｉＯ2、Ｙ2Ｏ3、ＺｎＳｅ、ＺｎＳ、ＺｒＯ2が好ましく、ＳｉＯ、Ｔａ2Ｏ5、ＴｉＯ2、Ｙ2Ｏ3、ＺｎＳｅ、ＺｎＳ、ＺｒＯ2が特に好ましい。 Examples of the material for the high refractive index dielectric thin film include Sb 2 O 3 , Sb 2 S 3 , Bi 2 O 3 , CeO 2 , CeF 3 , HfO 2 , La 2 O 3 , Nd 2 O 3 , and Pr 6. O 11 , Sc 2 O 3 , SiO, Ta 2 O 5 , TiO 2 , TlCl, Y 2 O 3 , ZnSe, ZnS, ZrO 2 and the like can be mentioned. Among these, Bi 2 O 3 , CeO 2 , CeF 3 , HfO 2 , SiO, Ta 2 O 5 , TiO 2 , Y 2 O 3 , ZnSe, ZnS, ZrO 2 are preferable, and SiO, Ta 2 O 5 , TiO 2 , Y 2 O 3 , ZnSe, ZnS and ZrO 2 are particularly preferred.
　低屈折率の誘電体薄膜の材料としては、例えば、Ａｌ2Ｏ3、ＢｉＦ3、ＣａＦ2、ＬａＦ3、ＰｂＣｌ2、ＰｂＦ2、ＬｉＦ、ＭｇＦ2、ＭｇＯ、ＮｄＦ3、ＳｉＯ2、Ｓｉ2Ｏ3、ＮａＦ、ＴｈＯ2、ＴｈＦ4などが挙げられる。これらの中でも、Ａｌ2Ｏ3、ＢｉＦ3、ＣａＦ2、ＭｇＦ2、ＭｇＯ、ＳｉＯ2、Ｓｉ2Ｏ3が好ましく、Ａｌ2Ｏ3、ＣａＦ2、ＭｇＦ2、ＭｇＯ、ＳｉＯ2、Ｓｉ2Ｏ3が特に好ましい。
　なお、誘電体薄膜の材料においては、原子比について特に制限はなく、目的に応じて適宜選択することができ、成膜時に雰囲気ガス濃度を変えることにより、原子比を調整することができる。 Examples of the material for the low refractive index dielectric thin film include Al 2 O 3 , BiF 3 , CaF 2 , LaF 3 , PbCl 2 , PbF 2 , LiF, MgF 2 , MgO, NdF 3 , SiO 2 , Si 2 O. 3 , NaF, ThO 2 , ThF 4 and the like. Among these, Al 2 O 3 , BiF 3 , CaF 2 , MgF 2 , MgO, SiO 2 and Si 2 O 3 are preferable, and Al 2 O 3 , CaF 2 , MgF 2 , MgO, SiO 2 and Si 2 O 3 are preferable. Is particularly preferred.
The material of the dielectric thin film is not particularly limited with respect to the atomic ratio, and can be appropriately selected according to the purpose. The atomic ratio can be adjusted by changing the atmospheric gas concentration during film formation.
　誘電体薄膜の成膜方法としては、特に制限はなく、目的に応じて適宜選択することができ、例えば、イオンプレーティング、イオンビーム等の真空蒸着法、スパッタリング法等の物理的気相成長法（ＰＶＤ法）、化学的気相成長法（ＣＶＤ法）などが挙げられる。これらの中でも、真空蒸着法、スパッタリング法が好ましく、スパッタリング法が特に好ましい。
　スパッタリング法としては、成膜速度の高いＤＣスパッタリング法が好ましい。なお、ＤＣスパッタリング法においては、導電性が高い材料を用いることが好ましい。
　また、スパッタリング法により多層成膜する方法としては、例えば、（１）１つのチャンバで複数のターゲットから交互又は順番に成膜する１チャンバ法と、（２）複数のチャンバで連続的に成膜するマルチチャンバ法とがある。これらの中でも、生産性の観点及び材料コンタミネーションを防ぐ観点から、マルチチャンバ法が特に好ましい。
　誘電体薄膜の厚みとしては、光学波長オーダーで、λ／１６～λの厚みが好ましく、λ／８～３λ／４がより好ましく、λ／６～３λ／８がより好ましい。 The method for forming the dielectric thin film is not particularly limited and can be appropriately selected depending on the purpose. For example, physical vapor deposition such as ion plating, vacuum deposition such as ion beam, sputtering, etc. (PVD method), chemical vapor deposition method (CVD method) and the like. Among these, the vacuum evaporation method and the sputtering method are preferable, and the sputtering method is particularly preferable.
As the sputtering method, a DC sputtering method having a high film formation rate is preferable. In the DC sputtering method, it is preferable to use a material having high conductivity.
In addition, as a method for forming a multilayer film by a sputtering method, for example, (1) a one-chamber method for forming a film alternately or sequentially from a plurality of targets in one chamber, and (2) a continuous film formation in a plurality of chambers. There is a multi-chamber method. Among these, the multi-chamber method is particularly preferable from the viewpoint of productivity and the viewpoint of preventing material contamination.
The thickness of the dielectric thin film is preferably λ / 16 to λ, more preferably λ / 8 to 3λ / 4, and more preferably λ / 6 to 3λ / 8 in the optical wavelength order.
　誘電体蒸着層中を伝播する光は、誘電体薄膜毎に光の一部が多重反射し、それらの反射光が干渉して誘電体薄膜の厚みと光に対する膜の屈折率との積で決まる波長の光のみが選択的に透過される。また、誘電体蒸着層の中心透過波長は入射光に対して角度依存性を有しており、入射光を変化させると透過波長を変えることができる。 The light propagating in the dielectric deposition layer is determined by the product of the thickness of the dielectric thin film and the refractive index of the film with respect to the light due to multiple reflections of part of the light for each dielectric thin film. Only light of a wavelength is selectively transmitted. Further, the central transmission wavelength of the dielectric vapor deposition layer has an angle dependency with respect to the incident light, and the transmission wavelength can be changed by changing the incident light.
　（ｉｉ）複屈折の異なる薄膜を積層した偏光子としては、例えば特表平９－５０６８３７号公報などに記載されたものを用いることができる。具体的には、特定の屈折率関係を得るために選ばれた条件下で加工すると、広く様々な材料を用いて、偏光子を形成できる。一般に、第一の材料の一つが、選ばれた方向において、第二の材料とは異なる屈折率を有することが好ましい。この屈折率の違いは、フィルムの形成中、又はフィルムの形成後の延伸、押出成形、或いはコーティングを含む様々な方法で達成できる。更に、２つの材料が同時押出することができるように、類似のレオロジー特性（例えば、溶融粘度）を有することが好ましい。
　複屈折の異なる薄膜を積層した偏光子としては、市販品を用いることができ、市販品としては、例えば、ＤＢＥＦ（登録商標）（３Ｍ社製）などが挙げられる。 (Ii) As a polarizer in which thin films having different birefringence are laminated, for example, those described in JP-T-9-506837 can be used. Specifically, when processed under conditions selected to obtain a specific refractive index relationship, a polarizer can be formed using a wide variety of materials. In general, it is preferred that one of the first materials has a different refractive index than the second material in the chosen direction. This difference in refractive index can be achieved in a variety of ways, including stretching, extrusion, or coating during or after film formation. Furthermore, it is preferred to have similar rheological properties (eg, melt viscosity) so that the two materials can be coextruded.
Commercially available products can be used as the polarizer in which thin films having different birefringence are laminated. Examples of commercially available products include DBEF (registered trademark) (manufactured by 3M).
　（ｉｉｉ）ワイヤーグリッド偏光子は、金属細線の複屈折によって、偏光の一方を透過し、他方を反射させる偏光子である。
ワイヤーグリッド偏光子は、金属ワイヤーを周期的に配列したもので、テラヘルツ波帯域で主に偏光子として用いられる。ワイヤーグリッドが偏光子として機能するためには，ワイヤー間隔が入射電磁波の波長よりも十分小さいことが好ましい。
　ワイヤーグリッド偏光子では、金属ワイヤーが等間隔に配列されている。金属ワイヤーの長手方向と平行な偏光方向の偏光成分はワイヤーグリッド偏光子において反射され、垂直な偏光方向の偏光成分はワイヤーグリッド偏光子を透過する。 (Iii) A wire grid polarizer is a polarizer that transmits one of polarized light and reflects the other by birefringence of a fine metal wire.
The wire grid polarizer is a periodic arrangement of metal wires, and is mainly used as a polarizer in the terahertz wave band. In order for the wire grid to function as a polarizer, it is preferable that the wire interval is sufficiently smaller than the wavelength of the incident electromagnetic wave.
In the wire grid polarizer, metal wires are arranged at equal intervals. The polarization component in the polarization direction parallel to the longitudinal direction of the metal wire is reflected by the wire grid polarizer, and the polarization component in the perpendicular polarization direction is transmitted through the wire grid polarizer.
　ワイヤーグリッド偏光子としては、市販品を用いることができ、市販品としては、例えば、エドモンドオプティクス社製のワイヤーグリッド偏光フィルタ５０×５０、ＮＴ４６－６３６などが挙げられる。 As the wire grid polarizer, a commercially available product can be used, and examples of the commercially available product include a wire grid polarizing filter 50 × 50, NT46-636 manufactured by Edmund Optics.
＜偏光反射板：円偏光反射層＞
　円偏光反射層を用いることにより、成形樹脂層側からの入射光を円偏光として反射させることができる。また、ハーフミラーを画像表示機能付きミラーに用いる場合、画像表示装置からの入射光を円偏光として透過させることができる。そのため、円偏光反射層を用いたハーフミラーおよびこのハーフミラーを用いた画像表示機能付きミラーでは、偏光サングラスを介しても、方向に依存せずに、画像およびミラー反射像の観察を行うことができる。 <Polarized reflector: Circularly polarized reflective layer>
By using the circularly polarized light reflecting layer, incident light from the molding resin layer side can be reflected as circularly polarized light. Moreover, when using a half mirror for a mirror with an image display function, incident light from the image display device can be transmitted as circularly polarized light. Therefore, in a half mirror using a circularly polarized reflection layer and a mirror with an image display function using this half mirror, an image and a mirror reflection image can be observed through polarization sunglasses without depending on the direction. it can.
　円偏光反射層の例としては、直線偏光反射板と１／４波長板とを含む積層型円偏光反射層およびコレステリック液晶層を含むコレステリック円偏光反射層が挙げられる。 Examples of the circularly polarized light reflecting layer include a laminated circularly polarized light reflecting layer including a linearly polarized light reflecting plate and a quarter wavelength plate, and a cholesteric circularly polarized light reflecting layer including a cholesteric liquid crystal layer.
［直線偏光反射板と１／４波長板とを含む積層型円偏光反射層］
　積層型円偏光反射層において、直線偏光反射板と１／４波長板とは直線偏光反射板の偏光反射軸に対し１／４波長板の遅相軸が４５°となるように配置されていればよい。また、１／４波長板と直線偏光反射板とは、例えば、接着層により接着されていればよい。
　ハーフミラーを画像表示機能付きミラーに用いる場合、積層型円偏光反射層において直線偏光反射板が画像表示装置に近い面となるように配置して使用する。その結果、画像表示装置からの画像表示のための光を効率よく円偏光に変換して、画像表示機能付きミラーの観察面から出射させることができる。画像表示装置からの画像表示のための光が直線偏光であるとき、この直線偏光を透過するように直線偏光反射板の偏光反射軸を調整すればよい。
　直線偏光反射板と１／４波長板とを含む円偏光反射層の厚みは、好ましくは２．０μｍ～３００μｍの範囲、より好ましくは８．０μｍ～２００μｍの範囲であればよい。
　直線偏光反射板としては、上記で直線偏光反射層として説明したものを用いることができる。
　１／４波長板としては、後述する１／４波長板を用いることができる。 [Laminated circularly polarized light reflection layer including linearly polarized light reflection plate and quarter wave plate]
In the laminated circularly polarized light reflecting layer, the linearly polarized light reflecting plate and the quarter wavelength plate are arranged so that the slow axis of the quarter wavelength plate is 45 ° with respect to the polarized light reflecting axis of the linearly polarized light reflecting plate. That's fine. Moreover, the quarter wave plate and the linearly polarized light reflecting plate may be bonded by, for example, an adhesive layer.
When a half mirror is used for a mirror with an image display function, the linearly polarized light reflection plate is arranged and used in the laminated circularly polarized light reflection layer so as to be a surface close to the image display device. As a result, light for image display from the image display device can be efficiently converted into circularly polarized light and emitted from the observation surface of the mirror with an image display function. When the light for image display from the image display device is linearly polarized light, the polarization reflection axis of the linearly polarized light reflecting plate may be adjusted so as to transmit this linearly polarized light.
The thickness of the circularly polarized light reflecting layer including the linearly polarized light reflecting plate and the quarter wavelength plate is preferably in the range of 2.0 μm to 300 μm, more preferably in the range of 8.0 μm to 200 μm.
As the linearly polarized light reflecting plate, those described above as the linearly polarized light reflecting layer can be used.
As the quarter wavelength plate, a quarter wavelength plate described later can be used.
［コレステリック円偏光反射層］
　コレステリック円偏光反射層はコレステリック液晶層を少なくとも１層含む。コレステリック円偏光反射層に含まれるコレステリック液晶層は可視光領域で選択反射を示すものであればよい。
　円偏光反射層は２層以上のコレステリック液晶層を含んでいてもよく、配向層などの他の層を含んでいてもよい。円偏光反射層はコレステリック液晶層のみからなることが好ましい。また、円偏光反射層が複数のコレステリック液晶層を含むときは、それらは隣接するコレステリック液晶層と直接接していることが好ましい。円偏光反射層は、３層、４層など、３層以上のコレステリック液晶層を含んでいることが好ましい。
　コレステリック円偏光反射層の厚みは、好ましくは１．０μｍ～３００μｍの範囲、より好ましくは１．５μｍ～１００μｍの範囲、さらに好ましくは２．０μｍ～２０μｍの範囲であればよい。 [Cholesteric circularly polarized reflective layer]
The cholesteric circularly polarized light reflection layer includes at least one cholesteric liquid crystal layer. The cholesteric liquid crystal layer included in the cholesteric circularly polarized light reflection layer may be any layer that exhibits selective reflection in the visible light region.
The circularly polarized light reflecting layer may include two or more cholesteric liquid crystal layers, and may include other layers such as an alignment layer. The circularly polarized light reflecting layer is preferably composed only of a cholesteric liquid crystal layer. Further, when the circularly polarized light reflection layer includes a plurality of cholesteric liquid crystal layers, it is preferable that they are in direct contact with adjacent cholesteric liquid crystal layers. The circularly polarized light reflection layer preferably includes three or more cholesteric liquid crystal layers such as three layers and four layers.
The thickness of the cholesteric circularly polarized light reflecting layer is preferably in the range of 1.0 μm to 300 μm, more preferably in the range of 1.5 μm to 100 μm, and still more preferably in the range of 2.0 μm to 20 μm.
　本明細書において、コレステリック液晶層は、コレステリック液晶相を固定した層を意味する。コレステリック液晶層を単に液晶層ということもある。
　コレステリック液晶相は、特定の波長域において右円偏光または左円偏光のいずれか一方のセンスの円偏光を選択的に反射させるとともに他方のセンスの円偏光を選択的に透過する円偏光選択反射を示すことが知られている。本明細書において、円偏光選択反射を単に選択反射ということもある。 In this specification, a cholesteric liquid crystal layer means a layer in which a cholesteric liquid crystal phase is fixed. The cholesteric liquid crystal layer is sometimes simply referred to as a liquid crystal layer.
The cholesteric liquid crystal phase selectively reflects circularly polarized light of either right circularly polarized light or left circularly polarized light in a specific wavelength region and selectively transmits circularly polarized light of the other sense. It is known to show. In this specification, the circularly polarized light selective reflection is sometimes simply referred to as selective reflection.
　円偏光選択反射を示すコレステリック液晶相を固定した層を含むフィルムとして、重合性液晶化合物を含む組成物から形成されたフィルムは従来から数多く知られており、コレステリック液晶層については、それらの従来技術を参照することができる。 Many films formed from a composition containing a polymerizable liquid crystal compound have been known as films containing a layer in which a cholesteric liquid crystal phase exhibiting circularly polarized light selective reflection is fixed. For cholesteric liquid crystal layers, those conventional techniques are known. Can be referred to.
　コレステリック液晶層は、コレステリック液晶相となっている液晶化合物の配向が保持されている層であればよい。典型的には、重合性液晶化合物をコレステリック液晶相の配向状態としたうえで、紫外線照射、加熱等によって重合、硬化し、流動性が無い層を形成して、同時に、外場や外力によって配向形態に変化を生じさせることない状態に変化した層であればよい。なお、コレステリック液晶層においては、コレステリック液晶相の光学的性質が層中において保持されていれば十分であり、層中の液晶化合物はもはや液晶性を示していなくてもよい。例えば、重合性液晶化合物は、硬化反応により高分子量化して、もはや液晶性を失っていてもよい。 The cholesteric liquid crystal layer may be a layer that maintains the orientation of the liquid crystal compound that is in the cholesteric liquid crystal phase. Typically, a polymerizable liquid crystal compound is brought into an orientation state of a cholesteric liquid crystal phase, and then polymerized and cured by ultraviolet irradiation, heating, etc. to form a non-flowable layer, and simultaneously aligned by an external field or an external force. Any layer may be used as long as the shape is not changed. In the cholesteric liquid crystal layer, it is sufficient that the optical properties of the cholesteric liquid crystal phase are maintained in the layer, and the liquid crystal compound in the layer may no longer exhibit liquid crystallinity. For example, the polymerizable liquid crystal compound may have a high molecular weight due to a curing reaction and may no longer have liquid crystallinity.
　コレステリック液晶層の選択反射の中心波長λは、コレステリック液晶相における螺旋構造のピッチＰ（＝螺旋の周期）に依存し、コレステリック液晶層の平均屈折率ｎとλ＝ｎ×Ｐの関係に従う。なお、コレステリック液晶層の選択反射中心波長と半値幅は下記のように求めることができる。
　分光光度計ＵＶ３１５０（島津製作所）を用いて光反射層の透過スペクトル（コレステリック液晶層の法線方向から測定したもの）を測定すると、選択反射領域に透過率の低下ピークがみられる。この最も大きいピーク高さの１／２の高さの透過率となる２つの波長のうち、短波長側の波長の値をλl（ｎｍ）、長波長側の波長の値をλh（ｎｍ）とすると、選択反射の中心波長と半値幅は下記式で表すことができる。
選択反射中心波長＝（λl＋λh）／２半値幅＝（λh－λl）
　上記のように求められる、コレステリック液晶層が有する選択反射の中心波長λは、コレステリック液晶層の法線方向から測定した円偏光反射スペクトルの反射ピークの重心位置にある波長と通常一致する。なお、本明細書において、選択反射の中心波長はコレステリック液晶層の法線方向から測定した時の中心波長を意味する。
　上記式から分かるように、螺旋構造のピッチを調節することによって、選択反射の中心波長を調整できる。ｎ値とＰ値を調節して、所望の波長の光に対して右円偏光および左円偏光のいずれか一方を選択的に反射させるために、中心波長λを調節することができる。 The central wavelength λ of selective reflection of the cholesteric liquid crystal layer depends on the pitch P (= spiral period) of the helical structure in the cholesteric liquid crystal phase, and follows the relationship between the average refractive index n of the cholesteric liquid crystal layer and λ = n × P. The selective reflection center wavelength and the half width of the cholesteric liquid crystal layer can be obtained as follows.
When the transmission spectrum of the light reflection layer (measured from the normal direction of the cholesteric liquid crystal layer) is measured using a spectrophotometer UV3150 (Shimadzu Corporation), a peak of reduced transmittance is observed in the selective reflection region. Of the two wavelengths having a transmittance of ½ of the largest peak height, the wavelength value on the short wavelength side is λ l (nm), and the wavelength value on the long wavelength side is λ h (nm ), The center wavelength and the full width at half maximum of selective reflection can be expressed by the following equations.
Selective reflection center wavelength = (λ l + λ h ) / 2 half width = (λ h −λ l )
The center wavelength λ of selective reflection possessed by the cholesteric liquid crystal layer, obtained as described above, usually coincides with the wavelength at the center of gravity of the reflection peak of the circularly polarized reflection spectrum measured from the normal direction of the cholesteric liquid crystal layer. In the present specification, the center wavelength of selective reflection means the center wavelength when measured from the normal direction of the cholesteric liquid crystal layer.
As can be seen from the above equation, the center wavelength of selective reflection can be adjusted by adjusting the pitch of the helical structure. The center wavelength λ can be adjusted in order to selectively reflect either the right circularly polarized light or the left circularly polarized light with respect to light of a desired wavelength by adjusting the n value and the P value.
　コレステリック液晶層に対して斜めに光が入射する場合は、選択反射の中心波長は短波長側にシフトする。そのため、画像表示のために必要とされる選択反射の波長に対して、上記のλ＝ｎ×Ｐの式に従って計算されるλが長波長となるようにｎ×Ｐを調整することが好ましい。屈折率ｎ2のコレステリック液晶層中でコレステリック液晶層の法線方向（コレステリック液晶層の螺旋軸方向）に対して光線がθ2の角度で通過するときの選択反射の中心波長をλdとするとき、λdは以下の式で表される。
λd＝ｎ2×Ｐ×ｃｏｓθ2 When light is incident on the cholesteric liquid crystal layer at an angle, the center wavelength of selective reflection is shifted to the short wavelength side. Therefore, it is preferable to adjust n × P so that λ calculated according to the above formula λ = n × P becomes a long wavelength with respect to the wavelength of selective reflection required for image display. In the cholesteric liquid crystal layer having a refractive index n 2 , the center wavelength of selective reflection when a light beam passes at an angle of θ 2 with respect to the normal direction of the cholesteric liquid crystal layer (helical axis direction of the cholesteric liquid crystal layer) is λ d . Λ d is expressed by the following equation.
λ d = n 2 × P × cos θ 2
　本発明のハーフミラーを画像表示機能付きミラーに用いる場合、上記を考慮して、円偏光反射層に含まれるコレステリック液晶層の選択反射の中心波長を設計することにより、画像の斜めからの視認性の低下を防止することができる。また、画像の斜めからの視認性を意図的に低下させることもできる。また、上記の選択反射の性質により、本発明のハーフミラーまたは本発明のハーフミラーを含む画像表示機能付きミラーにおいて、斜め方向から見た画像またはミラー反射像に、色味が出ることがある。円偏光反射層に赤外光領域に選択反射の中心波長を有するコレステリック液晶層を含ませることによって、このような色味を防止することも可能である。この場合の赤外光領域の選択反射の中心波長は具体的には、７８０～９００ｎｍ、好ましくは７８０～８５０ｎｍにあればよい。
　赤外光領域に選択反射の中心波長を有するコレステリック液晶層を設ける場合は、可視光領域に選択反射の中心波長をそれぞれ有するコレステリック液晶層すべてに対し最も外側にあることが好ましく、観察面から最も遠い層にあることがより好ましい。 When the half mirror of the present invention is used for a mirror with an image display function, the central wavelength of selective reflection of the cholesteric liquid crystal layer included in the circularly polarized light reflection layer is designed in consideration of the above, thereby making it possible to see the image from an oblique direction. Can be prevented. Also, the visibility of the image from an oblique direction can be intentionally reduced. Further, due to the selective reflection property described above, in the half mirror of the present invention or the mirror with an image display function including the half mirror of the present invention, a color may appear in an image viewed from an oblique direction or a mirror reflection image. By including a cholesteric liquid crystal layer having a central wavelength of selective reflection in the infrared light region in the circularly polarized light reflecting layer, it is possible to prevent such a color. In this case, the center wavelength of selective reflection in the infrared region is specifically 780 to 900 nm, preferably 780 to 850 nm.
When a cholesteric liquid crystal layer having a central wavelength of selective reflection is provided in the infrared light region, it is preferably outermost with respect to all the cholesteric liquid crystal layers each having a central wavelength of selective reflection in the visible light region. More preferably in a distant layer.
　コレステリック液晶相のピッチは重合性液晶化合物とともに用いるキラル剤の種類、またはその添加濃度に依存するため、これらを調整することによって所望のピッチを得ることができる。なお、螺旋のセンスやピッチの測定法については「液晶化学実験入門」日本液晶学会編　シグマ出版２００７年出版、４６頁、および「液晶便覧」液晶便覧編集委員会　丸善　１９６頁に記載の方法を用いることができる。 Since the pitch of the cholesteric liquid crystal phase depends on the type of chiral agent used together with the polymerizable liquid crystal compound or the concentration of the chiral agent, a desired pitch can be obtained by adjusting these. For the method of measuring spiral sense and pitch, use the methods described in “Introduction to Liquid Crystal Chemistry Experiments” edited by the Japanese Liquid Crystal Society, Sigma Publishing 2007, page 46, and “Liquid Crystal Handbook”, Liquid Crystal Handbook Editorial Committee, Maruzen, page 196. be able to.
　ハーフミラーにおいて、円偏光反射層は、赤色光の波長域に選択反射の中心波長を有するコレステリック液晶層と、緑色光の波長域に選択反射の中心波長を有するコレステリック液晶層と、青色光の波長域に選択反射の中心波長を有するコレステリック液晶層とを含むことが好ましい。反射層は、例えば、４００ｎｍ～５００ｎｍに選択反射の中心波長を有するコレステリック液晶層、５００ｎｍ～５８０ｎｍに選択反射の中心波長を有するコレステリック液晶層、および５８０ｎｍ～７００ｎｍに選択反射の中心波長を有するコレステリック液晶層を含むことが好ましい。 In the half mirror, the circularly polarized light reflection layer includes a cholesteric liquid crystal layer having a central wavelength of selective reflection in the wavelength range of red light, a cholesteric liquid crystal layer having a central wavelength of selective reflection in the wavelength range of green light, and a wavelength of blue light. And a cholesteric liquid crystal layer having a central wavelength of selective reflection in the region. The reflective layer is, for example, a cholesteric liquid crystal layer having a central wavelength of selective reflection in 400 nm to 500 nm, a cholesteric liquid crystal layer having a central wavelength of selective reflection in 500 nm to 580 nm, and a cholesteric liquid crystal having a central wavelength of selective reflection in 580 nm to 700 nm. It is preferable to include a layer.
　また、円偏光反射層が複数のコレステリック液晶層を含むときは、より画像表示装置に近いコレステリック液晶層がより長い選択反射の中心波長を有していることが好ましい。このような構成により、画像における斜め色味を抑えることができる。 Further, when the circularly polarized light reflecting layer includes a plurality of cholesteric liquid crystal layers, it is preferable that the cholesteric liquid crystal layer closer to the image display device has a longer selective reflection center wavelength. With such a configuration, it is possible to suppress an oblique color tone in an image.
　特に、１／４波長板を含まないコレステリック円偏光反射層を利用した画像表示機能付きミラーにおいて、各コレステリック液晶層が有する選択反射の中心波長は、画像表示装置の発光のピークの波長と５ｎｍ以上異なるようにすることが好ましい。この差異は、１０ｎｍ以上とすることもより好ましい。選択反射の中心波長と画像表示装置の画像表示のための発光ピークの波長をずらすことにより、画像表示のための光がコレステリック液晶層で反射されず、表示画像を明るくすることができる。画像表示装置の発光のピークの波長は画像表示装置の白表示時の発光スペクトルで確認できる。ピーク波長は上記発光スペクトルの可視光領域におけるピーク波長であればよく、例えば、画像表示装置の上述の赤色光の発光ピーク波長λＲ、緑色光の発光ピーク波長λＧ、および青色光の発光ピーク波長λＢからなる群から選択されるいずれか１つ以上であればよい。コレステリック液晶層が有する選択反射の中心波長は、画像表示装置の上述の赤色光の発光ピーク波長λＲ、緑色光の発光ピーク波長λＧ、および青色光の発光ピーク波長λＢのいずれとも５ｎｍ以上異なっていることが好ましく、１０ｎｍ以上異なっていることがより好ましい。円偏光反射層が複数のコレステリック液晶層を含む場合は、すべてのコレステリック液晶層の選択反射の中心波長を、画像表示装置の発光する光のピークの波長と好ましくは５ｎｍ以上、より好ましくは１０ｎｍ以上異なるようにすればよい。例えば、画像表示装置が白表示時の発光スペクトルにおいて赤色光の発光ピーク波長λＲと、緑色光の発光ピーク波長λＧと、青色光の発光ピーク波長λＢとを示すフルカラー表示の表示装置である場合、コレステリック液晶層が有する選択反射の中心波長がいずれも、λＲ、λＧ、およびλＢのいずれとも好ましくは５ｎｍ以上、より好ましくは１０ｎｍ以上異なるようにすればよい。さらに、円偏光反射層がλ１、λ２、およびλ３で表される互いに異なる選択反射の中心波長を有する３つのコレステリック液晶層を含む場合は、λＢ＜λ１＜λＧ＜λ２＜λＲ＜λ３の関係が満たされていることが好ましい。 In particular, in a mirror with an image display function using a cholesteric circularly polarized reflection layer that does not include a quarter-wave plate, the center wavelength of selective reflection that each cholesteric liquid crystal layer has is 5 nm or more with the wavelength of the emission peak of the image display device. It is preferable to make them different. This difference is more preferably 10 nm or more. By shifting the center wavelength of selective reflection and the wavelength of the emission peak for image display of the image display device, the light for image display is not reflected by the cholesteric liquid crystal layer, and the display image can be brightened. The wavelength of the emission peak of the image display device can be confirmed by the emission spectrum when the image display device displays white. The peak wavelength may be any peak wavelength in the visible light region of the emission spectrum. For example, the above-described red light emission peak wavelength λR, green light emission peak wavelength λG, and blue light emission peak wavelength λB of the image display device. Any one or more selected from the group consisting of: The selective reflection center wavelength of the cholesteric liquid crystal layer is different from the above-described red light emission peak wavelength λR, green light emission peak wavelength λG, and blue light emission peak wavelength λB of the image display device by 5 nm or more. It is preferable that the difference is 10 nm or more. When the circularly polarized light reflection layer includes a plurality of cholesteric liquid crystal layers, the central wavelength of selective reflection of all the cholesteric liquid crystal layers is preferably 5 nm or more, more preferably 10 nm or more, with the peak wavelength of light emitted from the image display device. It should be different. For example, when the image display device is a full-color display device showing an emission peak wavelength λR of red light, an emission peak wavelength λG of green light, and an emission peak wavelength λB of blue light in the emission spectrum during white display, All of the central wavelengths of selective reflection of the cholesteric liquid crystal layer may be different from each of λR, λG, and λB by 5 nm or more, more preferably by 10 nm or more. Further, when the circularly polarized light reflecting layer includes three cholesteric liquid crystal layers having different central wavelengths of selective reflection represented by λ1, λ2, and λ3, the relationship of λB <λ1 <λG <λ2 <λR <λ3 is established. It is preferable that it is satisfy | filled.
　ハーフミラーを画像表示機能付きミラーに用いる場合、使用するコレステリック液晶層の選択反射の中心波長を、画像表示装置の発光波長域、および円偏光反射層の使用態様に応じて調整することにより光利用効率良く明るい画像を表示することができる。円偏光反射層の使用態様としては、特に円偏光反射層への光の入射角、画像観察方向などが挙げられる。 When a half mirror is used as a mirror with an image display function, light is used by adjusting the center wavelength of selective reflection of the cholesteric liquid crystal layer to be used according to the emission wavelength range of the image display device and the usage mode of the circularly polarized reflection layer. A bright image can be displayed efficiently. Examples of the usage of the circularly polarized light reflecting layer include an incident angle of light to the circularly polarized light reflecting layer, an image observation direction, and the like.
　各コレステリック液晶層としては、螺旋のセンスが右および左のいずれかであるコレステリック液晶層が用いられる。コレステリック液晶層の反射円偏光のセンスは螺旋のセンスに一致する。複数のコレステリック液晶層の螺旋のセンスは全て同じであっても、異なるものが含まれていてもよい。すなわち、右および左のいずれか一方のセンスのコレステリック液晶層を含んでいてもよく、右および左の双方のセンスのコレステリック液晶層を含んでいてもよい。ただし、１／４波長板を含む画像表示機能付きミラーにおいては、複数のコレステリック液晶層の螺旋のセンスは全て同じであることが好ましい。そのときの螺旋のセンスは、各コレステリック液晶層として、画像表示装置から出射して１／４波長板を透過して得られているセンスの円偏光のセンスに応じて決定すればよい。具体的には、画像表示装置から出射して１／４波長板を透過して得られているセンスの円偏光を透過する螺旋のセンスを有するコレステリック液晶層を用いればよい。 As each cholesteric liquid crystal layer, a cholesteric liquid crystal layer whose spiral sense is either right or left is used. The sense of reflected circularly polarized light in the cholesteric liquid crystal layer coincides with the sense of a spiral. The spiral senses of the plurality of cholesteric liquid crystal layers may all be the same or different. In other words, either the right or left sense cholesteric liquid crystal layer may be included, or both the right and left sense cholesteric liquid crystal layers may be included. However, in the mirror with an image display function including a quarter wavelength plate, it is preferable that the spiral senses of the plurality of cholesteric liquid crystal layers are all the same. The spiral sense at that time may be determined according to the sense of circularly polarized light of the sense obtained as each cholesteric liquid crystal layer emitted from the image display device and transmitted through the quarter-wave plate. Specifically, a cholesteric liquid crystal layer having a spiral sense that transmits the circularly polarized light of the sense obtained from the image display device and transmitted through the quarter wavelength plate may be used.
　選択反射を示す選択反射帯の半値幅Δλ（ｎｍ）は、Δλが液晶化合物の複屈折Δｎと上記ピッチＰに依存し、Δλ＝Δｎ×Ｐの関係に従う。そのため、選択反射帯の幅の制御は、Δｎを調整して行うことができる。Δｎの調整は重合性液晶化合物の種類やその混合比率を調整したり、配向固定時の温度を制御したりすることで行うことができる。
　選択反射の中心波長が同一の１種のコレステリック液晶層の形成のために、ピッチＰが同じで、同じ螺旋のセンスのコレステリック液晶層を複数積層してもよい。ピッチＰが同じで、同じ螺旋のセンスのコレステリック液晶層を積層することによっては、特定の波長で円偏光選択性を高くすることができる。 The full width at half maximum Δλ (nm) of the selective reflection band showing selective reflection depends on the relationship of Δλ = Δn × P, where Δλ depends on the birefringence Δn of the liquid crystal compound and the pitch P. Therefore, the width of the selective reflection band can be controlled by adjusting Δn. Δn can be adjusted by adjusting the kind of the polymerizable liquid crystal compound and the mixing ratio thereof, or by controlling the temperature at the time of fixing the alignment.
In order to form one type of cholesteric liquid crystal layer having the same selective reflection center wavelength, a plurality of cholesteric liquid crystal layers having the same pitch P and the same spiral sense may be stacked. By laminating cholesteric liquid crystal layers having the same pitch P and the same spiral sense, the circularly polarized light selectivity can be increased at a specific wavelength.
＜１／４波長板＞
　ハーフミラーを画像表示機能付きミラーに用いる場合、ハーフミラーは、さらに１／４波長板を含み、成形樹脂層、偏光反射板（好ましくは円偏光反射板層、より好ましくはコレステリック円偏光反射板層）、および１／４波長板をこの順で含むことが好ましい。偏光反射板と１／４波長板とが互いに直接接していることが好ましい。また１／４波長板は画像表示装置とコレステリック円偏光反射層との間となるように配置されることが好ましい。画像表示装置とコレステリック円偏光反射層との間に１／４波長板を含むことによっては、特に、直線偏光により画像表示している画像表示装置からの光を円偏光に変換してコレステリック円偏光反射層に入射させることが可能となる。そのため、円偏光反射層において反射されて画像表示装置側に戻る光を大幅に減らすことができ、明るい画像の表示が可能となる。また、１／４波長板の利用によりコレステリック円偏光反射層において画像表示装置側に反射するセンスの円偏光を生じさせない構成が可能であるため、画像表示装置およびハーフミラーの間の多重反射に基づく画像表示品質の低下が生じにくい。
　すなわち、例えば、コレステリック円偏光反射層に含まれるコレステリック液晶層の選択反射の中心波長が、画像表示装置の白表示時の発光スペクトルにおける青色光の発光ピーク波長と略同一（例えば差異が５ｎｍ未満）であったとしても、円偏光反射層において画像表示側に反射するセンスの円偏光を生じさせることなく、画像表示装置の出射光を観察面側に透過させることができる。 <1/4 wavelength plate>
When the half mirror is used as a mirror with an image display function, the half mirror further includes a quarter wavelength plate, a molded resin layer, a polarizing reflector (preferably a circularly polarizing reflector layer, more preferably a cholesteric circularly polarizing reflector layer). ) And a quarter-wave plate in this order. It is preferable that the polarizing reflection plate and the quarter wavelength plate are in direct contact with each other. The quarter-wave plate is preferably disposed so as to be between the image display device and the cholesteric circularly polarizing reflection layer. By including a quarter-wave plate between the image display device and the cholesteric circularly polarized light reflection layer, in particular, the light from the image display device displaying an image by linearly polarized light is converted into circularly polarized light, and the cholesteric circularly polarized light is converted. It is possible to make the light incident on the reflective layer. Therefore, the light reflected by the circularly polarized light reflection layer and returning to the image display device side can be greatly reduced, and a bright image can be displayed. In addition, since a cholesteric circularly polarized light reflection layer can be configured not to generate sense circularly polarized light reflected to the image display device side by using a quarter wavelength plate, it is based on multiple reflections between the image display device and the half mirror. The image display quality is unlikely to deteriorate.
That is, for example, the center wavelength of selective reflection of the cholesteric liquid crystal layer included in the cholesteric circularly polarizing reflection layer is substantially the same as the emission peak wavelength of blue light in the emission spectrum during white display of the image display device (for example, the difference is less than 5 nm). Even in such a case, the emitted light of the image display device can be transmitted to the observation surface side without causing the circularly polarized light reflection layer to generate the sense circularly polarized light reflected to the image display side.
　コレステリック円偏光反射層と組み合わせて用いられる１／４波長板は画像表示装置に接着した際に、画像が最も明るくなるように、角度調整されていることが好ましい。すなわち、特に直線偏光により画像表示している画像表示装置に対し、上記直線偏光を最もよく透過させるように上記直線偏光の偏光方向（透過軸）と１／４波長板の遅相軸との関係が調整されていることが好ましい。例えば、一層型の１／４波長板の場合、上記透過軸と遅相軸とは４５°の角度をなしていることが好ましい。直線偏光により画像表示している画像表示装置から出射した光は１／４波長板を透過後、右および左のいずれかのセンスの円偏光となっている。円偏光反射層は、上記のセンスの円偏光を透過する捩れ方向を有するコレステリック液晶層で構成されていればよい。 The quarter-wave plate used in combination with the cholesteric circularly polarized reflective layer is preferably angle-adjusted so that the image is brightest when bonded to the image display device. That is, the relationship between the polarization direction of the linearly polarized light (transmission axis) and the slow axis of the quarter-wave plate so that the linearly polarized light is transmitted best, particularly for an image display device displaying an image by linearly polarized light. Is preferably adjusted. For example, in the case of a single layer type quarter wave plate, it is preferable that the transmission axis and the slow axis form an angle of 45 °. The light emitted from the image display device displaying an image by linearly polarized light is circularly polarized light of either right or left sense after passing through the quarter wavelength plate. The circularly polarized light reflecting layer may be formed of a cholesteric liquid crystal layer having a twist direction that transmits the circularly polarized light having the above-described sense.
　１／４波長板は可視光領域において１／４波長板として機能する位相差層であればよい。１／４波長板の例としては、一層型の１／４波長板、１／４波長板と１／２波長板とを積層した広帯域１／４波長板などが挙げられる。
　前者の１／４波長板の正面位相差は、画像表示装置の発光波長の１／４の長さであればよい。それゆえに例えば画像表示装置の発光波長が４５０ｎｍ、５３０ｎｍ、６４０ｎｍの場合は、４５０ｎｍの波長で好ましくは１１２．５ｎｍ±１０ｎｍ、より好ましくは１１２．５ｎｍ±５ｎｍ、さらに好ましくは１１２．５ｎｍ、５３０ｎｍの波長で好ましくは１３２．５ｎｍ±１０ｎｍ、より好ましくは、１３２．５ｎｍ±５ｎｍ、さらに好ましくは１３２．５ｎｍ、６４０ｎｍの波長で好ましくは１６０ｎｍ±１０ｎｍ、より好ましくは、１６０ｎｍ±５ｎｍ、さらに好ましくは１６０ｎｍの位相差であるような逆分散性の位相差層が１／４波長板として最も好ましいが、位相差の波長分散性の小さい位相差板や順分散性の位相差板も用いることができる。なお、逆分散性とは長波長になるほど位相差の絶対値が大きくなる性質を意味し、順分散性とは短波長になるほど位相差の絶対値が大きくなる性質を意味する。 The quarter wave plate may be a retardation layer that functions as a quarter wave plate in the visible light region. Examples of the quarter wavelength plate include a single layer type quarter wavelength plate, a broadband quarter wavelength plate in which a quarter wavelength plate and a half wavelength plate are laminated, and the like.
The front phase difference of the former quarter-wave plate may be a length that is ¼ of the emission wavelength of the image display device. Therefore, for example, when the emission wavelength of the image display device is 450 nm, 530 nm, or 640 nm, the wavelength of 450 nm is preferably 112.5 nm ± 10 nm, more preferably 112.5 nm ± 5 nm, still more preferably 112.5 nm, 530 nm. Preferably at 132.5 nm ± 10 nm, more preferably at 132.5 nm ± 5 nm, more preferably at 132.5 nm and 640 nm, preferably at 160 nm ± 10 nm, more preferably at 160 nm ± 5 nm, more preferably at 160 nm. A reverse-dispersion retardation layer that is a phase difference is most preferable as the quarter-wave plate, but a retardation plate having a small retardation wavelength dispersion or a forward-dispersion retardation plate can also be used. The reverse dispersion means a property that the absolute value of the phase difference becomes larger as the wavelength becomes longer, and the forward dispersion means a property that the absolute value of the phase difference becomes larger as the wavelength becomes shorter.
　積層型の１／４波長板は、１／４波長板と１／２波長板とをその遅相軸を６０°の角度で貼り合わせ、１／２波長板側を直線偏光の入射側に配置して、且つ１／２波長板の遅相軸を入射直線偏光の偏光面に対して１５°、または７５°に交差して使用するもので、位相差の逆分散性が良好なため好適に用いることができる。 The laminated quarter-wave plate is composed of a quarter-wave plate and a half-wave plate that are bonded to each other with the slow axis at an angle of 60 °, and the half-wave plate side is disposed on the incident side of linearly polarized light. In addition, the slow axis of the half-wave plate is used so as to cross 15 ° or 75 ° with respect to the polarization plane of the incident linearly polarized light, and is preferable because the reverse dispersion of the phase difference is good. Can be used.
　１／４波長板としては、特に制限はなく、目的に応じて適宜選択することができる。例えば、石英板、延伸されたポリカーボネートフィルム、延伸されたノルボルネン系ポリマーフィルム、炭酸ストロンチウムのような複屈折を示す無機粒子を含有して配向させた透明フィルム、支持体上に無機誘電体を斜め蒸着した薄膜などが挙げられる。 There is no restriction | limiting in particular as a quarter wavelength plate, According to the objective, it can select suitably. For example, quartz plate, stretched polycarbonate film, stretched norbornene polymer film, transparent film containing inorganic particles exhibiting birefringence such as strontium carbonate, and oblique deposition of inorganic dielectric on support Thin films and the like.
　１／４波長板としては、例えば、（１）特開平５－２７１１８号公報、及び特開平５－２７１１９号公報に記載された、レターデーションが大きい複屈折性フィルムと、レターデーションが小さい複屈折性フィルムとを、それらの光軸が直交するように積層させた位相差板、（２）特開平１０－６８８１６号公報に記載された、特定波長において１／４波長となっているポリマーフィルムと、それと同一材料からなり同じ波長において１／２波長となっているポリマーフィルムとを積層させて、広い波長域で１／４波長が得られる位相差板、（３）特開平１０－９０５２１号公報に記載された、二枚のポリマーフィルムを積層することにより広い波長域で１／４波長を達成できる位相差板、（４）国際公開第００／２６７０５号パンフレットに記載された変性ポリカーボネートフィルムを用いた広い波長域で１／４波長を達成できる位相差板、（５）国際公開第００／６５３８４号パンフレットに記載されたセルロースアセテートフィルムを用いた広い波長域で１／４波長を達成できる位相差板、などが挙げられる。
　１／４波長板としては、市販品を用いることもでき、市販品としては、例えば、ピュアエース（登録商標）ＷＲ（帝人株式会社製ポリカーボネートフィルム）などが挙げられる。 Examples of the quarter-wave plate include (1) a birefringent film having a large retardation and a birefringence having a small retardation described in JP-A-5-27118 and JP-A-5-27119. A retardation film in which the optical axes are laminated so that their optical axes are orthogonal to each other; (2) a polymer film described in JP-A-10-68816 and having a quarter wavelength at a specific wavelength; And a retardation film which is obtained by laminating a polymer film made of the same material and having a ½ wavelength at the same wavelength to obtain a ¼ wavelength in a wide wavelength range, (3) JP-A-10-90521 (4) International Publication No. 00/26705 pamphlet, which can achieve a quarter wavelength in a wide wavelength range by laminating two polymer films. A retardation plate capable of achieving a quarter wavelength in a wide wavelength range using the modified polycarbonate film described above, (5) 1 in a wide wavelength range using a cellulose acetate film described in International Publication No. 00/65384 pamphlet And a retardation plate capable of achieving a / 4 wavelength.
A commercially available product can also be used as the ¼ wavelength plate. Examples of the commercially available product include Pure Ace (registered trademark) WR (polycarbonate film manufactured by Teijin Limited).
　１／４波長板は、重合性液晶化合物、高分子液晶化合物を配列させて固定して形成してもよい。例えば、１／４波長板は、仮支持体、または配向膜表面に液晶組成物を塗布し、そこで液晶組成物中の重合性液晶化合物を液晶状態においてネマチック配向に形成後、光架橋や熱架橋によって固定化して、形成することができる。液晶組成物または製法について、詳細は後述する。１／４波長板は、高分子液晶化合物を含む組成物を、仮支持体、支持体、または配向膜表面に液晶組成物を塗布して液晶状態においてネマチック配向に形成後、冷却することによって配向を固定化して得られる層であってもよい。
　１／４波長板はコレステリック円偏光反射層と、接着層により接着されていてもよく、直接接していてもよく、後者が好ましい。 The quarter wavelength plate may be formed by arranging and fixing a polymerizable liquid crystal compound or a polymer liquid crystal compound. For example, for a quarter-wave plate, a liquid crystal composition is applied to the temporary support or the alignment film surface, and after forming a polymerizable liquid crystal compound in the liquid crystal composition in a nematic alignment in a liquid crystal state, photocrosslinking or thermal crosslinking is performed. Can be formed by immobilization. Details of the liquid crystal composition or the production method will be described later. The quarter-wave plate is aligned by applying a liquid crystal composition on the surface of a temporary support, support or alignment film to form a nematic alignment in a liquid crystal state and then cooling the composition containing a polymer liquid crystal compound. It may be a layer obtained by immobilizing.
The quarter wave plate may be adhered to the cholesteric circularly polarized light reflecting layer by an adhesive layer, or may be in direct contact with the latter, and the latter is preferred.
＜コレステリック液晶層および液晶組成物から形成される１／４波長板の作製方法＞
　以下、コレステリック液晶層および液晶組成物から形成される１／４波長板の作製材料および作製方法について説明する。
　上記１／４波長板の形成に用いる材料としては、重合性液晶化合物を含む液晶組成物などが挙げられる。上記コレステリック液晶層の形成に用いる材料としては、さらにキラル剤（光学活性化合物）とを含む液晶組成物などが挙げられる。必要に応じてさらに界面活性剤や重合開始剤などと混合して溶剤などに溶解した上記液晶組成物を、仮支持体、支持体、配向膜、下層となるコレステリック液晶層、１／４波長板などに塗布し、配向熟成後、液晶組成物の硬化により固定化してコレステリック液晶層または１／４波長板を形成することができる。 <Method for Producing 1/4 Wave Plate Formed from Cholesteric Liquid Crystal Layer and Liquid Crystal Composition>
Hereinafter, a preparation material and a preparation method of a quarter-wave plate formed from a cholesteric liquid crystal layer and a liquid crystal composition will be described.
Examples of the material used for forming the quarter wavelength plate include a liquid crystal composition containing a polymerizable liquid crystal compound. Examples of the material used for forming the cholesteric liquid crystal layer include a liquid crystal composition containing a chiral agent (optically active compound). If necessary, the above liquid crystal composition mixed with a surfactant or a polymerization initiator and dissolved in a solvent is used as a temporary support, a support, an alignment film, a lower cholesteric liquid crystal layer, a quarter-wave plate. After the alignment ripening, the liquid crystal composition is fixed by curing, and a cholesteric liquid crystal layer or a quarter wavelength plate can be formed.
［重合性液晶化合物］
　重合性液晶化合物としては、棒状液晶化合物を用いればよい。
　棒状の重合性液晶化合物の例としては、棒状ネマチック液晶化合物が挙げられる。棒状ネマチック液晶化合物としては、アゾメチン類、アゾキシ類、シアノビフェニル類、シアノフェニルエステル類、安息香酸エステル類、シクロヘキサンカルボン酸フェニルエステル類、シアノフェニルシクロヘキサン類、シアノ置換フェニルピリミジン類、アルコキシ置換フェニルピリミジン類、フェニルジオキサン類、トラン類およびアルケニルシクロヘキシルベンゾニトリル類が好ましく用いられる。低分子液晶化合物だけではなく、高分子液晶化合物も用いることができる。 [Polymerizable liquid crystal compound]
A rod-like liquid crystal compound may be used as the polymerizable liquid crystal compound.
Examples of the rod-like polymerizable liquid crystal compound include a rod-like nematic liquid crystal compound. Examples of rod-like nematic liquid crystal compounds include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines. , Phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles are preferably used. Not only low-molecular liquid crystal compounds but also high-molecular liquid crystal compounds can be used.
　重合性液晶化合物は、重合性基を液晶化合物に導入することで得られる。重合性基の例には、不飽和重合性基、エポキシ基、およびアジリジニル基が含まれ、不飽和重合性基が好ましく、エチレン性不飽和重合性基が特に好ましい。重合性基は種々の方法で、液晶化合物の分子中に導入できる。重合性液晶化合物が有する重合性基の個数は、好ましくは１～６個、より好ましくは１～３個である。重合性液晶化合物の例は、Ｍａｃｒｏｍｏｌ．Ｃｈｅｍ．，１９０巻、２２５５頁（１９８９年）、Ａｄｖａｎｃｅｄ　Ｍａｔｅｒｉａｌｓ　５巻、１０７頁（１９９３年）、米国特許第４６８３３２７号明細書、同５６２２６４８号明細書、同５７７０１０７号明細書、ＷＯ９５／２２５８６Ａ、ＷＯ９５／２４４５５Ａ、ＷＯ９７／００６００Ａ、ＷＯ９８／２３５８０Ａ、ＷＯ９８／５２９０５Ａ、特開平１－２７２５５１号公報、同６－１６６１６号公報、同７－１１０４６９号公報、同１１－８００８１号公報、および特開２００１－３２８９７３号公報などに記載の化合物が含まれる。２種類以上の重合性液晶化合物を併用してもよい。２種類以上の重合性液晶化合物を併用すると、配向温度を低下させることができる。 The polymerizable liquid crystal compound can be obtained by introducing a polymerizable group into the liquid crystal compound. Examples of the polymerizable group include an unsaturated polymerizable group, an epoxy group, and an aziridinyl group, preferably an unsaturated polymerizable group, and particularly preferably an ethylenically unsaturated polymerizable group. The polymerizable group can be introduced into the molecule of the liquid crystal compound by various methods. The number of polymerizable groups possessed by the polymerizable liquid crystal compound is preferably 1 to 6, more preferably 1 to 3. Examples of polymerizable liquid crystal compounds are described in Macromol. Chem. 190, 2255 (1989), Advanced Materials, 5, 107 (1993), US Pat. No. 4,683,327, US Pat. No. 5,622,648, US Pat. No. 5,770,107, WO 95 / 22586A, WO 95 / 24455A. WO97 / 00600A, WO98 / 23580A, WO98 / 52905A, JP-A-1-272551, JP-A-6-16616, JP-A-7-110469, JP-A-11-80081, and JP-A-2001-328773. And the like. Two or more kinds of polymerizable liquid crystal compounds may be used in combination. When two or more kinds of polymerizable liquid crystal compounds are used in combination, the alignment temperature can be lowered.
　また、液晶組成物中の重合性液晶化合物の添加量は、液晶組成物の固形分質量（溶媒を除いた質量）に対して、８０質量％～９９．９質量％であることが好ましく、８５質量％～９９．５質量％であることがより好ましく、９０質量％～９９質量％であることが特に好ましい。 The addition amount of the polymerizable liquid crystal compound in the liquid crystal composition is preferably 80% by mass to 99.9% by mass with respect to the solid content mass (mass excluding the solvent) of the liquid crystal composition, 85 It is more preferably from 9% by mass to 99.5% by mass, and particularly preferably from 90% by mass to 99% by mass.
［キラル剤：光学活性化合物］
　コレステリック液晶層の形成に用いる液晶組成物はキラル剤を含んでいることが好ましい。キラル剤はコレステリック液晶相の螺旋構造を誘起する機能を有する。キラル化合物は、化合物によって誘起する螺旋のセンスまたは螺旋ピッチが異なるため、目的に応じて選択すればよい。
　キラル剤としては、特に制限はなく、公知の化合物を用いることができる。キラル剤の例としては、液晶デバイスハンドブック（第３章４－３項、ＴＮ、ＳＴＮ用カイラル剤、１９９頁、日本学術振興会第１４２委員会編、１９８９に記載）、特開２００３－２８７６２３号、特開２００２－３０２４８７号、特開２００２－８０４７８号、特開２００２－８０８５１号、特開２０１０－１８１８５２号または特開２０１４－０３４５８１号の各公報に記載の化合物が挙げられる。 [Chiral agent: optically active compound]
The liquid crystal composition used for forming the cholesteric liquid crystal layer preferably contains a chiral agent. The chiral agent has a function of inducing a helical structure of a cholesteric liquid crystal phase. The chiral compound may be selected according to the purpose because the helical sense or helical pitch induced by the compound is different.
There is no restriction | limiting in particular as a chiral agent, A well-known compound can be used. Examples of chiral agents include liquid crystal device handbook (Chapter 3, Section 4-3, TN, chiral agent for STN, page 199, edited by Japan Society for the Promotion of Science, 142th Committee, 1989), Japanese Patent Application Laid-Open No. 2003-287623. And compounds described in JP-A Nos. 2002-302487, 2002-80478, 2002-80851, 2010-181852 and 2014-034581.
　キラル剤は、一般に不斉炭素原子を含むが、不斉炭素原子を含まない軸性不斉化合物あるいは面性不斉化合物もキラル剤として用いることができる。軸性不斉化合物または面性不斉化合物の例には、ビナフチル、ヘリセン、パラシクロファンおよびこれらの誘導体が含まれる。キラル剤は、重合性基を有していてもよい。キラル剤と液晶化合物とがいずれも重合性基を有する場合は、重合性キラル剤と重合性液晶化合物との重合反応により、重合性液晶化合物から誘導される繰り返し単位と、キラル剤から誘導される繰り返し単位とを有するポリマーを形成することができる。この態様では、重合性キラル剤が有する重合性基は、重合性液晶化合物が有する重合性基と、同種の基であることが好ましい。従って、キラル剤の重合性基も、不飽和重合性基、エポキシ基またはアジリジニル基であることが好ましく、不飽和重合性基であることがさらに好ましく、エチレン性不飽和重合性基であることが特に好ましい。
　また、キラル剤は、液晶化合物であってもよい。 A chiral agent generally contains an asymmetric carbon atom, but an axially asymmetric compound or a planar asymmetric compound containing no asymmetric carbon atom can also be used as the chiral agent. Examples of the axial asymmetric compound or the planar asymmetric compound include binaphthyl, helicene, paracyclophane, and derivatives thereof. The chiral agent may have a polymerizable group. When both the chiral agent and the liquid crystal compound have a polymerizable group, they are derived from the repeating unit derived from the polymerizable liquid crystal compound and the chiral agent by a polymerization reaction between the polymerizable chiral agent and the polymerizable liquid crystal compound. A polymer having repeating units can be formed. In this aspect, the polymerizable group possessed by the polymerizable chiral agent is preferably the same group as the polymerizable group possessed by the polymerizable liquid crystal compound. Therefore, the polymerizable group of the chiral agent is also preferably an unsaturated polymerizable group, an epoxy group or an aziridinyl group, more preferably an unsaturated polymerizable group, and an ethylenically unsaturated polymerizable group. Particularly preferred.
The chiral agent may be a liquid crystal compound.
　キラル剤としては、イソソルビド誘導体、イソマンニド誘導体、またはビナフチル誘導体を好ましく用いることができる。イソソルビド誘導体としては、ＢＡＳＦ社製のＬＣ－７５６等の市販品を用いてもよい。
　液晶組成物における、キラル剤の含有量は、重合性液晶化合物の総モル量に対し０．０１モル％～２００モル％が好ましく、１．０モル％～３０モル％がより好ましい。 As the chiral agent, an isosorbide derivative, an isomannide derivative, or a binaphthyl derivative can be preferably used. As the isosorbide derivative, a commercial product such as LC-756 manufactured by BASF may be used.
The content of the chiral agent in the liquid crystal composition is preferably from 0.01 mol% to 200 mol%, more preferably from 1.0 mol% to 30 mol%, based on the total molar amount of the polymerizable liquid crystal compound.
［重合開始剤］
　液晶組成物は、重合開始剤を含有していることが好ましい。紫外線照射により重合反応を進行させる態様では、使用する重合開始剤は、紫外線照射によって重合反応を開始可能な光重合開始剤であることが好ましく、特にラジカル光重合開始剤が好ましい。ラジカル光重合開始剤の例には、α－カルボニル化合物（米国特許第２３６７６６１号、同２３６７６７０号の各明細書記載）、アシロインエーテル（米国特許第２４４８８２８号明細書記載）、α－炭化水素置換芳香族アシロイン化合物（米国特許第２７２２５１２号明細書記載）、多核キノン化合物（米国特許第３０４６１２７号、同２９５１７５８号の各明細書記載）、トリアリールイミダゾールダイマーとｐ－アミノフェニルケトンとの組み合わせ（米国特許第３５４９３６７号明細書記載）、アクリジンおよびフェナジン化合物（特開昭６０－１０５６６７号公報、米国特許第４２３９８５０号明細書記載）、アシルフォスフィンオキシド化合物（特公昭６３－４０７９９号公報、特公平５－２９２３４号公報、特開平１０－９５７８８号公報、特開平１０－２９９９７号公報記載）、オキシム化合物（特公昭６３－４０７９９号、特公平５－２９２３４号、特開平１０－９５７８８号、特開平１０－２９９９７号、特開２００１－２３３８４２号、特開２０００－８００６８号、特開２００６－３４２１６６号、特開２０１３－１１４２４９号、特開２０１４－１３７４６６号、特許４２２３０７１号、特開２０１０－２６２０２８号、特表２０１４－５００８５２号の各公報記載）およびオキサジアゾール化合物（米国特許第４２１２９７０号明細書記載）等が挙げられる。例えば、特開２０１２－２０８４９４号公報の段落０５００～０５４７の記載も参酌できる。 [Polymerization initiator]
The liquid crystal composition preferably contains a polymerization initiator. In the embodiment in which the polymerization reaction is advanced by ultraviolet irradiation, the polymerization initiator to be used is preferably a photopolymerization initiator capable of initiating the polymerization reaction by ultraviolet irradiation, and particularly preferably a radical photopolymerization initiator. Examples of radical photopolymerization initiators include α-carbonyl compounds (described in US Pat. Nos. 2,367,661 and 2,367,670), acyloin ether (described in US Pat. No. 2,448,828), α-hydrocarbon substitution Aromatic acyloin compounds (described in US Pat. No. 2,722,512), polynuclear quinone compounds (described in US Pat. Nos. 3,046,127 and 2,951,758), combinations of triarylimidazole dimers and p-aminophenyl ketone (US) No. 3549367), acridine and phenazine compounds (JP-A-60-105667, U.S. Pat. No. 4,239,850), acylphosphine oxide compounds (JP-B 63-40799, JP-B-5) -29234, JP-A-10-957 88, JP-A-10-29997), oxime compounds (JP-B 63-40799, JP-B 5-29234, JP-A 10-95788, JP-A 10-29997, JP-A 2001-233842). JP, 2000-80068, JP 2006-342166, JP 2013-114249, JP 2014-137466, JP 4223071, JP 2010-262028, and JP 2014-500852 Description) and oxadiazole compounds (described in US Pat. No. 4,221,970). For example, the description in paragraphs 0500 to 0547 of JP2012-208494A can be considered.
　重合開始剤としては、アシルフォスフィンオキシド化合物またはオキシム化合物を用いることも好ましい。
　アシルフォスフィンオキシド化合物としては、例えば、市販品のＢＡＳＦジャパン（株）製のＩＲＧＡＣＵＲＥ８１９（化合物名：ビス（２，４，６－トリメチルベンゾイル）－フェニルフォスフィンオキサイド）を用いることができる。オキシム化合物としては、ＩＲＧＡＣＵＲＥ　ＯＸＥ０１（ＢＡＳＦ社製）、ＩＲＧＡＣＵＲＥ　ＯＸＥ０２（ＢＡＳＦ社製）、ＴＲ－ＰＢＧ－３０４（常州強力電子新材料有限公司製）、アデカアークルズＮＣＩ－８３１、アデカアークルズＮＣＩ－９３０（ＡＤＥＫＡ社製）、アデカアークルズＮＣＩ－８３１（ＡＤＥＫＡ社製）等の市販品を用いることができる。 As the polymerization initiator, it is also preferable to use an acyl phosphine oxide compound or an oxime compound.
As the acylphosphine oxide compound, for example, IRGACURE819 (compound name: bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide) manufactured by BASF Japan Ltd. can be used. Examples of the oxime compounds include IRGACURE OXE01 (manufactured by BASF), IRGACURE OXE02 (manufactured by BASF), TR-PBG-304 (manufactured by Changzhou Strong Electronic New Materials Co., Ltd.), Adeka Arcles NCI-831, Adeka Arcles NCI-930 Commercial products such as (ADEKA) and Adeka Arcles NCI-831 (ADEKA) can be used.
　重合開始剤は、１種のみ用いてもよいし、２種以上を併用してもよい。
　液晶組成物中の重合開始剤の含有量は、重合性液晶化合物の含有量に対して０．１～２０質量％であることが好ましく、０．５質量％～５．０質量％であることがさらに好ましい。 Only one type of polymerization initiator may be used, or two or more types may be used in combination.
The content of the polymerization initiator in the liquid crystal composition is preferably 0.1 to 20% by mass, and preferably 0.5 to 5.0% by mass with respect to the content of the polymerizable liquid crystal compound. Is more preferable.
［架橋剤］
　液晶組成物は、硬化後の膜強度向上、耐久性向上のため、任意に架橋剤を含有していてもよい。架橋剤としては、紫外線、熱、湿気等で硬化するものが好適に使用できる。
　架橋剤としては、特に制限はなく、目的に応じて適宜選択することができ、例えばトリメチロールプロパントリ（メタ）アクリレート、ペンタエリスリトールトリ（メタ）アクリレート等の多官能アクリレート化合物；グリシジル（メタ）アクリレート、エチレングリコールジグリシジルエーテル等のエポキシ化合物；２，２－ビスヒドロキシメチルブタノール－トリス［３－（１－アジリジニル）プロピオネート］、４，４－ビス（エチレンイミノカルボニルアミノ）ジフェニルメタン等のアジリジン化合物；ヘキサメチレンジイソシアネート、ビウレット型イソシアネート等のイソシアネート化合物；オキサゾリン基を側鎖に有するポリオキサゾリン化合物；ビニルトリメトキシシラン、Ｎ－（２－アミノエチル）３－アミノプロピルトリメトキシシラン等のアルコキシシラン化合物などが挙げられる。また、架橋剤の反応性に応じて公知の触媒を用いることができ、膜強度および耐久性向上に加えて生産性を向上させることができる。これらは、１種単独で使用してもよいし、２種以上を併用してもよい。
　液晶組成物の架橋剤の含有量は、３．０質量％～２０質量％が好ましく、５．０質量％～１５質量％がより好ましい。架橋剤の含有量が３．０質量％以上であることにより、架橋密度向上の効果を得ることができる。また、２０質量％以下とすることにより、形成される層の安定性を維持することができる。 [Crosslinking agent]
The liquid crystal composition may optionally contain a crosslinking agent in order to improve the film strength after curing and improve the durability. As the cross-linking agent, one that can be cured by ultraviolet rays, heat, moisture, or the like can be suitably used.
There is no restriction | limiting in particular as a crosslinking agent, According to the objective, it can select suitably, For example, polyfunctional acrylate compounds, such as a trimethylol propane tri (meth) acrylate and pentaerythritol tri (meth) acrylate; Glycidyl (meth) acrylate , Epoxy compounds such as ethylene glycol diglycidyl ether; aziridine compounds such as 2,2-bishydroxymethylbutanol-tris [3- (1-aziridinyl) propionate], 4,4-bis (ethyleneiminocarbonylamino) diphenylmethane; hexa Isocyanate compounds such as methylene diisocyanate and biuret type isocyanate; polyoxazoline compounds having an oxazoline group in the side chain; vinyltrimethoxysilane, N- (2-aminoethyl) 3-aminopropylto Alkoxysilane compounds such as methoxy silane. Moreover, a well-known catalyst can be used according to the reactivity of a crosslinking agent, and productivity can be improved in addition to membrane strength and durability improvement. These may be used individually by 1 type and may use 2 or more types together.
The content of the crosslinking agent in the liquid crystal composition is preferably 3.0% by mass to 20% by mass, and more preferably 5.0% by mass to 15% by mass. When the content of the crosslinking agent is 3.0% by mass or more, an effect of improving the crosslinking density can be obtained. Moreover, the stability of the layer formed can be maintained by setting it as 20 mass% or less.
［配向制御剤］
　液晶組成物中には、安定的にまたは迅速にプレーナー配向とするために寄与する配向制御剤を添加してもよい。配向制御剤の例としては特開２００７－２７２１８５号公報の段落００１８～００４３等に記載のフッ素（メタ）アクリレート系ポリマー、特開２０１２－２０３２３７号公報の段落００３１～００３４等に記載の式（Ｉ）～（ＩＶ）で表される化合物などが挙げられる。
　なお、配向制御剤としては１種を単独で用いてもよいし、２種以上を併用してもよい。 [Orientation control agent]
In the liquid crystal composition, an alignment control agent that contributes to stable or rapid planar alignment may be added. Examples of the alignment control agent include fluorine (meth) acrylate polymers described in paragraphs 0018 to 0043 of JP 2007-272185 A, and formulas (I) described in paragraphs 0031 to 0034 of JP 2012-203237 A, and the like. ) To (IV).
In addition, as an orientation control agent, 1 type may be used independently and 2 or more types may be used together.
　液晶組成物中における、配向制御剤の添加量は、重合性液晶化合物の全質量に対して０．０１質量％～１０質量％が好ましく、０．０１質量％～５．０質量％がより好ましく、０．０２質量％～１．０質量％が特に好ましい。 The addition amount of the alignment control agent in the liquid crystal composition is preferably 0.01% by mass to 10% by mass and more preferably 0.01% by mass to 5.0% by mass with respect to the total mass of the polymerizable liquid crystal compound. 0.02% by mass to 1.0% by mass is particularly preferable.
［その他の添加剤］
　その他、液晶組成物は、塗膜の表面張力を調整し厚みを均一にするための界面活性剤、および重合性モノマー等の種々の添加剤から選ばれる少なくとも１種を含有していてもよい。また、液晶組成物中には、必要に応じて、さらに重合禁止剤、酸化防止剤、紫外線吸収剤、光安定化剤、色材、金属酸化物微粒子等を、光学的性能を低下させない範囲で添加することができる。 [Other additives]
In addition, the liquid crystal composition may contain at least one selected from a surfactant for adjusting the surface tension of the coating film to make the thickness uniform, and various additives such as a polymerizable monomer. Further, in the liquid crystal composition, if necessary, a polymerization inhibitor, an antioxidant, an ultraviolet absorber, a light stabilizer, a colorant, metal oxide fine particles, and the like may be added as long as the optical performance is not deteriorated. Can be added.
［溶媒］
　液晶組成物の調製に使用する溶媒としては、特に制限はなく、目的に応じて適宜選択することができ、有機溶媒が好ましく用いられる。
　有機溶媒としては、特に制限はなく、目的に応じて適宜選択することができ、例えばケトン類、アルキルハライド類、アミド類、スルホキシド類、ヘテロ環化合物、炭化水素類、エステル類、エーテル類などが挙げられる。これらは、１種単独で使用してもよいし、２種以上を併用してもよい。これらの中でも、環境への負荷を考慮した場合にはケトン類が特に好ましい。 [solvent]
There is no restriction | limiting in particular as a solvent used for preparation of a liquid-crystal composition, According to the objective, it can select suitably, An organic solvent is used preferably.
The organic solvent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include ketones, alkyl halides, amides, sulfoxides, heterocyclic compounds, hydrocarbons, esters, ethers and the like. Can be mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, ketones are particularly preferable in consideration of environmental load.
［塗布、配向、重合］
　仮支持体、配向膜、１／４波長板、下層となるコレステリック液晶層などへの液晶組成物の塗布方法は、特に制限はなく、目的に応じて適宜選択することができる。液晶組成物の塗布のほか、本明細書中で塗布というときの塗布方法としては、例えば、ワイヤーバーコーティング法、カーテンコーティング法、押し出しコーティング法、ダイレクトグラビアコーティング法、リバースグラビアコーティング法、ダイコーティング法、スピンコーティング法、ディップコーティング法、スプレーコーティング法、スライドコーティング法などが挙げられる。また、別途支持体上に塗設した液晶組成物を転写することによっても実施できる。塗布した液晶組成物を加熱することにより、液晶化合物を配向させる。コレステリック液晶層形成の際はコレステリック配向させればよく、１／４波長板形成の際は、ネマチック配向させることが好ましい。コレステリック配向の際、加熱温度は２００℃以下が好ましく、１３０℃以下がより好ましい。この配向処理により、重合性液晶化合物がフィルム面に対して実質的に垂直な方向に螺旋軸を有するようにねじれ配向している光学薄膜が得られる。ネマチック配向の際、加熱温度は５０℃～１２０℃が好ましく、６０℃～１００℃がより好ましい。 [Coating, orientation, polymerization]
The method for applying the liquid crystal composition to the temporary support, the alignment film, the quarter-wave plate, the lower cholesteric liquid crystal layer, etc. is not particularly limited and can be appropriately selected according to the purpose. In addition to the application of the liquid crystal composition, the application method in this specification includes, for example, a wire bar coating method, a curtain coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, and a die coating method. , Spin coating method, dip coating method, spray coating method, slide coating method and the like. It can also be carried out by transferring a liquid crystal composition separately coated on a support. The liquid crystal compound is aligned by heating the applied liquid crystal composition. In forming the cholesteric liquid crystal layer, cholesteric alignment may be performed, and in forming the quarter-wave plate, nematic alignment is preferable. In the cholesteric orientation, the heating temperature is preferably 200 ° C. or lower, and more preferably 130 ° C. or lower. By this alignment treatment, an optical thin film in which the polymerizable liquid crystal compound is twisted and aligned so as to have a helical axis in a direction substantially perpendicular to the film surface is obtained. In the nematic orientation, the heating temperature is preferably 50 ° C. to 120 ° C., more preferably 60 ° C. to 100 ° C.
　配向させた液晶化合物は、更に重合させ、液晶組成物を硬化することができる。重合は、熱重合、光照射を利用する光重合のいずれでもよいが、光重合が好ましい。光照射は、紫外線を用いることが好ましい。照射エネルギーは、２０ｍＪ／ｃｍ2～５０Ｊ／ｃｍ2が好ましく、１００ｍＪ／ｃｍ2～１，５００ｍＪ／ｃｍ2がより好ましい。光重合反応を促進するため、加熱条件下または窒素雰囲気下で光照射を実施してもよい。照射紫外線波長は３５０ｎｍ～４３０ｎｍが好ましい。重合反応率は安定性の観点から高いことが好ましく、７０％以上がより好ましく、８０％以上がさらに好ましい。重合反応率は、重合性基の消費割合をＩＲ吸収スペクトルを用いて測定することにより決定することができる。 The aligned liquid crystal compound can be further polymerized to cure the liquid crystal composition. The polymerization may be either thermal polymerization or photopolymerization utilizing light irradiation, but photopolymerization is preferred. It is preferable to use ultraviolet rays for light irradiation. The irradiation energy is preferably 20mJ / cm 2 ~ 50J / cm 2, 100mJ / cm 2 ~ 1,500mJ / cm 2 is more preferable. In order to accelerate the photopolymerization reaction, light irradiation may be performed under heating conditions or in a nitrogen atmosphere. The irradiation ultraviolet wavelength is preferably 350 nm to 430 nm. The polymerization reaction rate is preferably high from the viewpoint of stability, more preferably 70% or more, and further preferably 80% or more. The polymerization reaction rate can be determined by measuring the consumption rate of the polymerizable group using an IR absorption spectrum.
　個々のコレステリック液晶層の厚みは、上記特性を示す範囲であれば、特に限定されず、好ましくは０．５μｍ以上１００μｍ以下の範囲、より好ましくは１．０μｍ以上４０μｍ以下の範囲であればよい。また、液晶組成物から形成される１／４波長板の厚みは、特に限定されず、好ましくは０．２μｍ～１０μｍ、より好ましくは０．５μｍ～２．０μｍであればよい。 The thickness of each cholesteric liquid crystal layer is not particularly limited as long as it exhibits the above characteristics, and is preferably in the range of 0.5 to 100 μm, more preferably in the range of 1.0 to 40 μm. The thickness of the quarter wave plate formed from the liquid crystal composition is not particularly limited, and is preferably 0.2 μm to 10 μm, more preferably 0.5 μm to 2.0 μm.
［重合性液晶化合物から形成される層の積層膜］
　複数のコレステリック液晶層からなる積層膜、および１／４波長板と複数のコレステリック液晶層とからなる積層膜の形成の際は、それぞれ、１／４波長板または先のコレステリック液晶層の表面に直接、重合性液晶化合物等を含む液晶組成物を塗布し、配向および固定の工程を繰り返してもよく、別に用意した１／４波長板、コレステリック液晶層、またはそれらの積層体を接着剤等を用いて積層してもよく、前者が好ましい。接着層の厚みムラに由来する干渉ムラが観測されにくくなるからである。また、コレステリック液晶層の積層膜においては、先に形成されたコレステリック液晶層の表面に直接接するように次のコレステリック液晶層を形成することにより、先に形成したコレステリック液晶層の空気界面側の液晶分子の配向方位と、その上に形成するコレステリック液晶層の下側の液晶分子の配向方位が一致し、コレステリック液晶層の積層体の偏光特性が良好となるからである。 [Laminated film of layers formed from polymerizable liquid crystal compound]
When forming a multi-layer film composed of a plurality of cholesteric liquid crystal layers and a multi-layer film composed of a quarter-wave plate and a plurality of cholesteric liquid crystal layers, each is directly applied to the surface of the quarter-wave plate or the previous cholesteric liquid crystal layer. The liquid crystal composition containing a polymerizable liquid crystal compound or the like may be applied, and the steps of alignment and fixing may be repeated. A separately prepared quarter wave plate, cholesteric liquid crystal layer, or a laminate thereof is used with an adhesive or the like. The former is preferable. This is because the interference unevenness derived from the thickness unevenness of the adhesive layer becomes difficult to be observed. In the laminated film of the cholesteric liquid crystal layer, the liquid crystal on the air interface side of the cholesteric liquid crystal layer formed earlier is formed by forming the next cholesteric liquid crystal layer so as to be in direct contact with the surface of the cholesteric liquid crystal layer formed earlier. This is because the orientation direction of the molecules matches the orientation direction of the liquid crystal molecules below the cholesteric liquid crystal layer formed thereon, and the polarization property of the laminate of the cholesteric liquid crystal layer is improved.
［仮支持体、支持体、配向層］
　液晶組成物は、支持体、仮支持体、または、支持体もしくは仮支持体表面に形成された配向層の表面に塗布され層形成されていることが好ましい。支持体は層形成後に剥離しなくてよく、仮支持体、または、仮支持体および配向層は、層形成後に剥離されてもよい。
　仮支持体および支持体の例としては、プラスチックフィルムまたはガラス板が挙げられる。プラスチックフィルムの材料の例としては、ポリエチレンテレフタレート（ＰＥＴ）などのポリエステル、ポリカーボネート、アクリル樹脂、エポキシ樹脂、ポリウレタン、ポリアミド、ポリオレフィン、セルロース誘導体、シリコーンなどが挙げられる。プラスチックフィルムである仮支持体は、後述の転写シートの基材フィルムとして機能することも好ましい。仮支持体は、ハーフミラーが使用されるまで、例えば画像表示装置に接着されるまで、保護フィルムとして機能していてもよい。 [Temporary support, support, alignment layer]
The liquid crystal composition is preferably applied and layered on the surface of a support, a temporary support, or an alignment layer formed on the surface of the support or the temporary support. The support may not be peeled after the layer is formed, and the temporary support, or the temporary support and the alignment layer may be peeled after the layer is formed.
Examples of the temporary support and the support include a plastic film or a glass plate. Examples of the material of the plastic film include polyesters such as polyethylene terephthalate (PET), polycarbonate, acrylic resin, epoxy resin, polyurethane, polyamide, polyolefin, cellulose derivative, and silicone. It is also preferable that the temporary support which is a plastic film functions as a base film of a transfer sheet described later. The temporary support may function as a protective film until the half mirror is used, for example, until it is adhered to the image display device.
　配向層は、ポリマーなどの有機化合物（ポリイミド、ポリビニルアルコール、ポリエステル、ポリアリレート、ポリアミドイミド、ポリエーテルイミド、ポリアミド、変性ポリアミドなどの樹脂）のラビング処理、無機化合物の斜方蒸着、マイクログルーブを有する層の形成、またはラングミュア・ブロジェット法（ＬＢ法）を用いた有機化合物（例えば、ω－トリコサン酸、ジオクタデシルメチルアンモニウムクロライド、ステアリル酸メチル）の累積のような手段で、設けることができる。更に、電場の付与、磁場の付与または光照射により、配向機能が生じる配向層を用いてもよい。
　特にポリマーからなる配向層はラビング処理を行ったうえで、ラビング処理面に液晶組成物を塗布することが好ましい。ラビング処理は、ポリマー層の表面を、紙、布で一定方向に、数回擦ることにより実施することができる。
　配向層を設けずに仮支持体表面に、または仮支持体をラビング処理した表面に、液晶組成物を塗布してもよい。
　配向層の厚さは０．０１μｍ～５．０μｍであることが好ましく、０．０５μｍ～２．０μｍであることがさらに好ましい。 The alignment layer has a rubbing treatment of organic compounds such as polymers (resins such as polyimide, polyvinyl alcohol, polyester, polyarylate, polyamideimide, polyetherimide, polyamide, modified polyamide), oblique deposition of inorganic compounds, and microgrooves. It can be provided by means such as formation of a layer or accumulation of an organic compound (for example, ω-tricosanoic acid, dioctadecylmethylammonium chloride, methyl stearylate) using the Langmuir-Blodgett method (LB method). Further, an alignment layer that generates an alignment function by application of an electric field, application of a magnetic field, or light irradiation may be used.
In particular, the alignment layer made of a polymer is preferably subjected to a rubbing treatment and then a liquid crystal composition is applied to the rubbing treatment surface. The rubbing treatment can be performed by rubbing the surface of the polymer layer several times in a certain direction with paper or cloth.
The liquid crystal composition may be applied to the surface of the temporary support without providing the alignment layer, or to the surface on which the temporary support has been rubbed.
The thickness of the alignment layer is preferably 0.01 μm to 5.0 μm, and more preferably 0.05 μm to 2.0 μm.
＜高Ｒｅ位相差膜＞
　本発明のハーフミラーは高Ｒｅ位相差膜を含む。本明細書において、「高Ｒｅ位相差膜」というとき、１／４波長板（位相差板）とは区別される、高い正面位相差を有する位相差膜を意味する。高Ｒｅ位相差膜は、観察面と偏光反射板との間に少なくとも１つ含まれる。本発明のハーフミラーは、高Ｒｅ位相差膜が１つまたは２つ含まれていることが好ましい。 <High Re retardation film>
The half mirror of the present invention includes a high Re retardation film. In this specification, the term “high Re phase difference film” means a phase difference film having a high front phase difference, which is distinguished from a quarter wave plate (phase difference plate). At least one high Re retardation film is included between the observation surface and the polarizing reflector. The half mirror of the present invention preferably includes one or two high Re retardation films.
　本発明のハーフミラーは、高Ｒｅ位相差膜として第１の高Ｒｅ位相差膜を、観察面と成形樹脂層との間に、含む。本発明のハーフミラーは、高Ｒｅ位相差膜として第１の高Ｒｅ位相差膜のみを含むことが好ましい。
　また、本発明のハーフミラーが２つ以上の高Ｒｅ位相差膜を含む場合、成形樹脂層と偏光反射板との間に、高Ｒｅ位相差膜として第２の高Ｒｅ位相差膜を、さらに含むことが好ましい。すなわち、成形樹脂層の両面に高Ｒｅ位相差膜が配置されていることが好ましい。
　本明細書において単に「高Ｒｅ位相差膜」として説明するときは、「第１の高Ｒｅ位相差膜」および「第２の高Ｒｅ位相差膜」のいずれにも該当するものとする。 The half mirror of the present invention includes the first high Re retardation film as the high Re retardation film between the observation surface and the molded resin layer. The half mirror of the present invention preferably includes only the first high Re retardation film as the high Re retardation film.
Further, when the half mirror of the present invention includes two or more high Re retardation films, a second high Re retardation film is further provided as a high Re retardation film between the molded resin layer and the polarizing reflector. It is preferable to include. That is, it is preferable that high Re retardation films are disposed on both surfaces of the molded resin layer.
In the present specification, when it is simply described as “high Re retardation film”, it corresponds to both “first high Re retardation film” and “second high Re retardation film”.
　本発明のハーフミラーが２つ以上の高Ｒｅ位相差膜を含む場合、２つ以上の高Ｒｅ位相差膜の遅相軸の方向は同じであることが好ましい。具体的には、本発明のハーフミラーが第１の高Ｒｅ位相差膜および第２の高Ｒｅ位相差膜を含む場合、第１の高Ｒｅ位相差膜の遅相軸の方向および第２の高Ｒｅ位相差膜の遅相軸の方向は同じであることが好ましい。この遅相軸の方向が同じである本発明のハーフミラーを用いることによって、画像のムラがより効率的に低減した画像表示装置を提供することができる。 When the half mirror of the present invention includes two or more high Re retardation films, the direction of the slow axis of the two or more High Re retardation films is preferably the same. Specifically, when the half mirror of the present invention includes the first high Re retardation film and the second high Re retardation film, the direction of the slow axis of the first high Re retardation film and the second The direction of the slow axis of the high Re retardation film is preferably the same. By using the half mirror of the present invention in which the direction of the slow axis is the same, it is possible to provide an image display device in which image unevenness is more efficiently reduced.
　高Ｒｅ位相差膜の正面位相差の合計は、３０００ｎｍ以上であることが好ましく、５０００ｎｍ以上であることがより好ましい。高Ｒｅ位相差膜の正面位相差の合計は、大きいほど好ましいが、製造効率や薄膜化を考慮して、１０００００ｎｍ以下が好ましく、５００００ｎｍ以下がより好ましく、４００００ｎｍ以下がさらに好ましく、３００００ｎｍ以下が特に好ましい。
　第１の高Ｒｅ位相差膜の正面位相差が３０００ｎｍ以上であることが好ましい。 The total front retardation of the high Re retardation film is preferably 3000 nm or more, and more preferably 5000 nm or more. The total front retardation of the high Re retardation film is preferably as large as possible, but is preferably 100000 nm or less, more preferably 50000 nm or less, still more preferably 40000 nm or less, and particularly preferably 30000 nm or less in consideration of production efficiency and thinning. .
The front retardation of the first high Re retardation film is preferably 3000 nm or more.
　また、本発明のハーフミラーが２つ以上の高Ｒｅ位相差膜を含む場合、それぞれの高Ｒｅ位相差膜の正面位相差は１５００ｎｍ以上であることが好ましく、２０００ｎｍ以上であることがより好ましく、３０００ｎｍ以上であることがさらに好ましい。また、２つ以上の高Ｒｅ位相差膜の正面位相差は、製造が容易になるため、それぞれ等しいことが好ましい。特に、本発明のハーフミラーが第１の高Ｒｅ位相差膜および第２の高Ｒｅ位相差膜を含む場合、第１の高Ｒｅ位相差膜および第２の高Ｒｅ位相差膜の正面位相差は等しいことが好ましい。 In addition, when the half mirror of the present invention includes two or more high Re retardation films, the front retardation of each high Re retardation film is preferably 1500 nm or more, more preferably 2000 nm or more, More preferably, it is 3000 nm or more. Further, it is preferable that the front phase differences of two or more high Re retardation films are equal to each other because manufacturing is easy. In particular, when the half mirror of the present invention includes the first high Re retardation film and the second high Re retardation film, the front retardation of the first high Re retardation film and the second high Re retardation film Are preferably equal.
　上述のように、成形樹脂層は、複屈折性が不均一となりやすい。ハーフミラーを画像表示機能付きミラーに使用する場合、画像を形成するための光は成形樹脂層を透過するため、上記の不均一な複屈折性の影響を受け、偏光サングラスを介して画像を観測すると明暗ムラや色ムラが生じる。同様にミラー反射像も成形樹脂層を２回透過した光により観測されるため、上記の不均一な複屈折性の影響を受け、偏光サングラスを介して画像を観測すると明暗ムラまたは色ムラが生じやすい。 As described above, the molded resin layer tends to have non-uniform birefringence. When a half mirror is used for a mirror with an image display function, the light for forming an image is transmitted through the molding resin layer, and therefore the image is observed through polarized sunglasses under the influence of the non-uniform birefringence described above. Then, light and dark unevenness and color unevenness occur. Similarly, since the mirror reflection image is also observed by the light that has passed through the molding resin layer twice, it is affected by the above-mentioned non-uniform birefringence, and when the image is observed through polarized sunglasses, light and dark unevenness or color unevenness occurs. Cheap.
　また、車両の窓ガラス、特にリアガラスに用いられる強化ガラス（例えば、合わせガラスの構成ではない強化ガラス）は複屈折分布を有することが知られている。そのため、車両のリアガラスなどを通過して画像表示機能付きミラー前面に入射する光に基づくミラー反射像には明暗ムラまたは色ムラが生じると考えられる。すなわち、複屈折分布により画像表示機能付きミラー前面に入射する光に分布を伴った偏光成分が生じると、画像表示機能付きミラー前面（最表面）での反射光と円偏光反射層での選択反射光との干渉によって反射光の強度の差が生じ、上述の明暗ムラまたは色ムラが生じうると考えられる。 Further, it is known that tempered glass (for example, tempered glass which is not a laminated glass) used for vehicle window glass, particularly rear glass, has a birefringence distribution. For this reason, it is considered that light and dark unevenness or color unevenness occurs in the mirror reflection image based on the light that passes through the rear glass of the vehicle and enters the front surface of the mirror with an image display function. In other words, when a polarized component with a distribution is generated in the light incident on the front surface of the mirror with the image display function due to the birefringence distribution, the reflected light on the front surface (outermost surface) of the mirror with the image display function and the selective reflection on the circularly polarized reflective layer It is considered that the difference in intensity of reflected light occurs due to interference with light, and the above-described brightness / darkness unevenness or color unevenness can occur.
　高Ｒｅ位相差膜は、偏光を疑似的に無偏光とすることができるため、明暗ムラや色ムラを解消することができる。
　偏光を疑似的に無偏光とすることができる正面位相差については、特開２００５－３２１５４４号公報の段落００２２～００３３に記載がある。具体的な正面位相差の数値は、成形樹脂層に応じて、また、後述の車両用画像表示機能付きミラーとして用いる場合については、成形樹脂層および車両に応じて決定することができる。 Since the high Re retardation film can make the polarized light non-polarized in a pseudo manner, it is possible to eliminate light and dark unevenness and color unevenness.
The front phase difference that can make the polarized light pseudo-non-polarized is described in paragraphs 0022 to 0033 of JP-A-2005-321544. The specific numerical value of the front phase difference can be determined according to the molded resin layer and, when used as a mirror with a vehicle image display function described later, according to the molded resin layer and the vehicle.
　高Ｒｅ位相差膜としては、プラスチックフィルムや、水晶板などの複屈折性材料を挙げることができる。プラスチックフィルムとしては、ポリエチレンテレフタレート（ＰＥＴ）などのポリエステルフィルム、ポリカーボネートフィルム、ポリアセタールフィルム、ポリアリレートフィルムなどが挙げられる。ＰＥＴを含む高い位相差を有する位相差膜については、特開２０１３－２５７５７９号公報、特開２０１５－１０２６３６号公報などを参照することができる。光学コスモシャイン（登録商標）超複屈折タイプ（東洋紡）などの市販品を用いてもよい。 Examples of the high Re retardation film include a birefringent material such as a plastic film and a quartz plate. Examples of the plastic film include polyester films such as polyethylene terephthalate (PET), polycarbonate films, polyacetal films, polyarylate films, and the like. JP-A-2013-257579, JP-A-2015-102636, and the like can be referred to for a retardation film having a high retardation including PET. Commercial products such as optical Cosmo Shine (registered trademark) super birefringence type (Toyobo) may be used.
　高い位相差を有するプラスチックフィルムは一般的には、樹脂を溶融押出ししてドラム上などにキャストしてフィルム状に成形し、これを加熱しながら、一軸、または二軸に２～５倍の延伸倍率で延伸することによって形成できる。また結晶化を促進しフィルムの強度を上げる目的で、延伸した後に延伸温度を超える温度で「熱固定」とよばれる熱処理を行ってもよい。 In general, plastic films with high phase difference are melt extruded and cast on a drum or the like to form a film, which is heated and stretched uniaxially or biaxially 2 to 5 times. It can be formed by stretching at a magnification. In order to promote crystallization and increase the strength of the film, a heat treatment called “heat setting” may be performed at a temperature exceeding the stretching temperature after stretching.
　位相差を有する膜を複数積層することにより、高Ｒｅ位相差膜を作製してもよい。複数の位相差を有する膜の間には、接着層などの他の層が含まれていてもよい。
　高Ｒｅ位相差膜の厚みは１．０μｍ～１００００μｍが好ましく、１０μｍ～１０００μｍがより好ましく、２０μｍ～２００μｍがさらに好ましい。 A high Re retardation film may be produced by laminating a plurality of films having a retardation. Other layers such as an adhesive layer may be included between the films having a plurality of retardations.
The thickness of the high Re retardation film is preferably 1.0 μm to 10,000 μm, more preferably 10 μm to 1000 μm, and even more preferably 20 μm to 200 μm.
＜光学機能層＞
　本発明のハーフミラーは、光学機能層を含んでいてもよい。光学機能層は本発明のハーフミラーにおいて、光学機能層、第１の高Ｒｅ位相差膜、成形樹脂層、および反射偏光板がこの順となるように設けられていることが好ましい。
　本発明のハーフミラーにおいて、光学機能層としては可視光領域で透明であるものが用いられる。
　光学機能層としては、ハードコート層、防眩層、反射防止層、または帯電防止層などが挙げられる。
　光学機能層は第１の高Ｒｅ位相差膜上に設けられた重合性組成物の硬化層であることが好ましい。光学機能層は第１の高Ｒｅ位相差膜上に設けられたあと、第１の高Ｒｅ位相差膜と一体となって、成形樹脂層上に設けられることが好ましい。 <Optical function layer>
The half mirror of the present invention may include an optical function layer. In the half mirror of the present invention, the optical functional layer is preferably provided so that the optical functional layer, the first high Re retardation film, the molded resin layer, and the reflective polarizing plate are in this order.
In the half mirror of the present invention, an optical functional layer that is transparent in the visible light region is used.
Examples of the optical functional layer include a hard coat layer, an antiglare layer, an antireflection layer, and an antistatic layer.
The optical functional layer is preferably a cured layer of a polymerizable composition provided on the first high Re retardation film. The optical functional layer is preferably provided on the molded resin layer after being provided on the first high Re retardation film and then being integrated with the first high Re retardation film.
［ハードコート層］
　ハードコート層はハーフミラーの最外層として含まれていてもよく、ハードコート層の外側にさらに他の層が設けられていてもよい。
　本明細書において、ハードコート層とは、形成されることでハーフミラー表面の鉛筆硬度が上昇する層をいう。具体的には、ハードコート層積層後の鉛筆硬度（ＪＩＳ Ｋ５４００）がＨ以上となる層である。ハードコート層積層後の鉛筆硬度は好ましくは２Ｈ以上であり、さらに好ましくは３Ｈ以上となっていればよい。ハードコート層の厚みは、０．１μｍ～１００μｍが好ましく、１．０μｍ～７０μｍがより好ましく、２．０μｍ～５０μｍがさらに好ましい。
　ハードコート層は反射防止層または帯電防止層などを兼ねるものであってもよい。 [Hard coat layer]
The hard coat layer may be included as the outermost layer of the half mirror, and another layer may be provided outside the hard coat layer.
In this specification, the hard coat layer refers to a layer that, when formed, increases the pencil hardness of the half mirror surface. Specifically, it is a layer having a pencil hardness (JIS K5400) of H or higher after the hard coat layer lamination. The pencil hardness after laminating the hard coat layer is preferably 2H or more, and more preferably 3H or more. The thickness of the hard coat layer is preferably 0.1 μm to 100 μm, more preferably 1.0 μm to 70 μm, and further preferably 2.0 μm to 50 μm.
The hard coat layer may also serve as an antireflection layer or an antistatic layer.
　ハードコート層の具体例としては、紫外線硬化性重合性化合物を含む組成物から形成された層が挙げられる。この組成物は粒子など他の成分を含んでいてもよい。紫外線硬化性重合性化合物としては（メタ）アクリレートが好ましい。ハードコート層の材料および作製方法については、特開２０１６－０７１０８５号公報、特開２０１２－１６８２９５号公報、特開２０１１－２２５８４６号公報等を参照することができる。 Specific examples of the hard coat layer include a layer formed from a composition containing an ultraviolet curable polymerizable compound. The composition may contain other components such as particles. As the ultraviolet curable polymerizable compound, (meth) acrylate is preferable. As for the material and the production method of the hard coat layer, reference can be made to JP-A-2016-071085, JP-A-2012-168295, JP-A-2011-225846, and the like.
［防眩層］
　防眩層は、表面散乱に基づく防眩性を付与するための層である。防眩層は、ハーフミラーの最外層として含まれていてもよく、防眩層の外側にさらに他の層が設けられていてもよい。
　防眩層は、防眩層用バインダー樹脂形成化合物と防眩層用粒子を含む組成物から形成することができる。
　防眩層の材料および作製方法については、特開２０１３－１７８５８４号公報の０１０１～０１０９の記載、特開２０１６－０５３６０１号公報等を参照することができる。 [Anti-glare layer]
The antiglare layer is a layer for imparting antiglare properties based on surface scattering. The antiglare layer may be included as the outermost layer of the half mirror, and another layer may be further provided outside the antiglare layer.
The antiglare layer can be formed from a composition containing a binder resin-forming compound for the antiglare layer and particles for the antiglare layer.
With respect to the material and production method of the antiglare layer, reference can be made to the descriptions of 0101 to 0109 of JP2013-178484A, JP2016-053601A, and the like.
［反射防止層］
　反射防止層は、ハーフミラーの最表面に含まれていることが好ましい。反射防止層を設けることによって、最表面の反射光が抑制され、偏光反射板からの光に由来する像に基づくミラー反射像を鮮明に観測することができる。反射防止層の材料および作製方法については、ＷＯ２０１５／０５０２０２Ａの００４９～００５３の記載を参照できる。 [Antireflection layer]
The antireflection layer is preferably included on the outermost surface of the half mirror. By providing the antireflection layer, the reflected light on the outermost surface is suppressed, and a mirror reflection image based on an image derived from the light from the polarizing reflection plate can be clearly observed. For the material and manufacturing method of the antireflection layer, the description in 0049 to 0053 of WO2015 / 050202A can be referred to.
［帯電防止層］
　帯電防止層は、ハーフミラーの最表面に含まれていることが好ましい。帯電防止層の材料および作製方法については、特開２０１２－０２７１９１号公報の００２０～００２８の記載を参照できる。 [Antistatic layer]
The antistatic layer is preferably contained on the outermost surface of the half mirror. Regarding the material and the production method of the antistatic layer, reference can be made to the description in JP-A-2012-027191, 0020 to 0028.
＜接着層＞
　ハーフミラーは、各層の接着のための接着層を含んでいてもよい。接着層は接着剤から形成されるものであればよい。成形樹脂層と偏光反射板との間に接着層を含むことが好ましい。また、第１の高Ｒｅ位相差膜と成型樹脂層との間に接着層を含むことが好ましい。また、第２の高Ｒｅ位相差膜と成型樹脂層との間に接着層を含むことが好ましい。
　接着剤としては硬化方式の観点から、熱硬化タイプ、光硬化タイプ、反応硬化タイプ、硬化の不要な感圧接着タイプがあり、それぞれ素材としてアクリレート系、ウレタン系、ウレタンアクリレート系、エポキシ系、エポキシアクリレート系、ポリオレフィン系、変性オレフィン系、ポリプロピレン系、エチレンビニルアルコール系、塩化ビニル系、クロロプレンゴム系、シアノアクリレート系、ポリアミド系、ポリイミド系、ポリスチレン系、ポリビニルブチラール系などの化合物を使用することができる。作業性、生産性の観点から、硬化方式として光硬化タイプが好ましく、光学的な透明性、耐熱性の観点から、素材はアクリレート系、ウレタンアクリレート系、エポキシアクリレート系などを使用することが好ましい。 <Adhesive layer>
The half mirror may include an adhesive layer for bonding the layers. The adhesive layer may be formed from an adhesive. It is preferable to include an adhesive layer between the molded resin layer and the polarizing reflector. Moreover, it is preferable that an adhesive layer is included between the first high Re retardation film and the molded resin layer. Moreover, it is preferable that an adhesive layer is included between the second high Re retardation film and the molded resin layer.
Adhesives include thermal curing type, photocuring type, reaction curing type, and pressure-sensitive adhesive type that does not require curing, from the viewpoint of curing method, and acrylate, urethane, urethane acrylate, epoxy, epoxy as materials It is possible to use compounds such as acrylate, polyolefin, modified olefin, polypropylene, ethylene vinyl alcohol, vinyl chloride, chloroprene rubber, cyanoacrylate, polyamide, polyimide, polystyrene, polyvinyl butyral, etc. it can. From the viewpoint of workability and productivity, the photocuring type is preferable as the curing method, and from the viewpoint of optical transparency and heat resistance, it is preferable to use an acrylate, urethane acrylate, epoxy acrylate, or the like material.
　硬化の不要な感圧接着タイプの接着層はシート状の市販の接着層を用いて形成することができる。いわゆる、高透明性接着剤転写テープ（ＯＣＡテープ）を用いて形成してもよい。高透明性接着剤転写テープとしては、画像表示装置用の市販品、特に画像表示装置の画像表示部表面用の市販品を用いればよい。市販品の例としては、パナック株式会社製の粘着シート（ＰＤ－Ｓ１など）、日栄化工株式会社のＭＨＭシリーズの粘着シートなどが挙げられる。
　例えば、成形樹脂層と高Ｒｅ位相差膜との接着は、硬化の不要な感圧接着タイプの接着層で行うことができる。 A pressure-sensitive adhesive type adhesive layer that does not require curing can be formed using a sheet-like commercially available adhesive layer. You may form using what is called a highly transparent adhesive transfer tape (OCA tape). As the highly transparent adhesive transfer tape, a commercially available product for an image display device, particularly a commercially available product for the image display unit surface of the image display device may be used. Examples of commercially available products include PANAC Corporation pressure-sensitive adhesive sheets (PD-S1 and the like), MHI Series MHM series pressure-sensitive adhesive sheets, and the like.
For example, adhesion between the molded resin layer and the high Re retardation film can be performed by a pressure-sensitive adhesive type adhesive layer that does not require curing.
＜熱可塑性溶着層＞
　ハーフミラーは、熱可塑性溶着層を含んでいてもよい。熱可塑性溶着層は層間の接着のために用いられる。熱可塑性溶着層は、加熱により溶解し、その後冷却することで層を接着させる。熱可塑性溶着層は成形樹脂層と他の層との接着に用いられることが好ましく、熱可塑性溶着層と成形樹脂層とは直接接していることが好ましい。熱可塑性溶着層は、特に、後述のように、成形樹脂層の射出成形等による製造と同時に、高Ｒｅ位相差膜または偏光反射板等を成形樹脂層のいずれか一方の表面に設けるときに用いられることが好ましい。成形樹脂層と熱可塑性溶着層とは両者の成分が混合した混合層を形成していてもよい。成形樹脂層と熱可塑性溶着層との間に混合層が形成されていてもよい。成形樹脂層と偏光反射板との間に熱可塑性溶着層を含むことが好ましい。また、第１の高Ｒｅ位相差膜と成型樹脂層との間に熱可塑性溶着層を含むことが好ましい。また、第２の高Ｒｅ位相差膜と成型樹脂層との間に熱可塑性溶着層を含むことが好ましい。 <Thermoplastic weld layer>
The half mirror may include a thermoplastic weld layer. The thermoplastic weld layer is used for adhesion between the layers. The thermoplastic weld layer is melted by heating and then cooled to adhere the layers. The thermoplastic weld layer is preferably used for adhesion between the molded resin layer and another layer, and the thermoplastic weld layer and the molded resin layer are preferably in direct contact with each other. The thermoplastic welding layer is used when a high Re phase difference film or a polarizing reflector is provided on one surface of the molded resin layer at the same time as the production of the molded resin layer by injection molding, as will be described later. It is preferred that The molded resin layer and the thermoplastic weld layer may form a mixed layer in which both components are mixed. A mixed layer may be formed between the molded resin layer and the thermoplastic weld layer. It is preferable to include a thermoplastic weld layer between the molded resin layer and the polarizing reflector. Moreover, it is preferable that a thermoplastic weld layer is included between the first high Re retardation film and the molded resin layer. Moreover, it is preferable that a thermoplastic weld layer is included between the second high Re retardation film and the molded resin layer.
　熱可塑性溶着層は熱可塑性樹脂を含む。熱可塑性樹脂の例としては、塩化ビニル樹脂、酢酸ビニル樹脂、塩化ビニルと酢酸ビニルとの共重合樹脂、エチレンと酢酸ビニルとの共重合樹脂、イソブテンと無水マレイン酸との共重合樹脂、（メタ）アクリル樹脂、（メタ）アクリル共重合樹脂、スチレンとブタジエンとの共重合樹脂、ウレタン樹脂、ポリエステル樹脂、エポキシ樹脂、シリコーン樹脂、変性シリコーン樹脂、ロジン樹脂、ポリビニルアセタール樹脂、クロロプレンゴム、ニトリルゴム、ニトリル樹脂などが挙げられる。 The thermoplastic weld layer contains a thermoplastic resin. Examples of thermoplastic resins include vinyl chloride resin, vinyl acetate resin, copolymer resin of vinyl chloride and vinyl acetate, copolymer resin of ethylene and vinyl acetate, copolymer resin of isobutene and maleic anhydride, (meta ) Acrylic resin, (meth) acrylic copolymer resin, copolymer resin of styrene and butadiene, urethane resin, polyester resin, epoxy resin, silicone resin, modified silicone resin, rosin resin, polyvinyl acetal resin, chloroprene rubber, nitrile rubber, A nitrile resin etc. are mentioned.
　熱可塑性溶着層の厚みは０．１μｍ～１００μｍであればよく、０．５μｍ～３０μｍであることが好ましく、１．０μｍ～８．０μｍであることがより好ましい。熱可塑性溶着層の厚みを１．０μｍ以上とすることにより、基材との十分な密着性が確実となる。また、熱可塑性溶着層の厚みを８．０μｍ以下とすることにより、表面粗さを抑えやすく、鏡面状が得られやすい。 The thickness of the thermoplastic weld layer may be 0.1 μm to 100 μm, preferably 0.5 μm to 30 μm, and more preferably 1.0 μm to 8.0 μm. By setting the thickness of the thermoplastic weld layer to 1.0 μm or more, sufficient adhesion with the substrate is ensured. Moreover, when the thickness of the thermoplastic weld layer is 8.0 μm or less, the surface roughness can be easily suppressed and a mirror-like shape can be easily obtained.
　熱可塑性溶着層は、熱可塑性樹脂を含む塗布液を偏光反射層または離型シート等の表面等に塗布して形成することができる。塗布液の溶媒としては、アミド（例、Ｎ，Ｎ－ジメチルホルムアミド）、スルホキシド（例、ジメチルスルホキシド）、ヘテロ環化合物（例、ピリジン）、炭化水素（例、ベンゼン、ヘキサン、シクロヘキサン）、アルキルハライド（例、クロロホルム、ジクロロメタン）、エステル（例、酢酸メチル、酢酸ブチル）、ケトン（例、アセトン、メチルエチルケトン、メチルイソブチルケトン、シクロヘキサノン）、エーテル（例、テトラヒドロフラン、１，２－ジメトキシエタン）、アルキルアルコール（例、メタノール、エタノール、プロパノール）が挙げられる。また、二種類以上の溶媒を混合して使用してもよい。上記の中で、アルキルハライド、エステル、ケトンおよびそれらの混合溶媒が好ましい。
　熱可塑性溶着層の形成のための塗布液としては、ヒートシール剤として市販の組成物をそのまま用いるか、または溶媒に溶解したもの、もしくは溶媒で希釈したものを用いることができる。 The thermoplastic welding layer can be formed by applying a coating liquid containing a thermoplastic resin to the surface of a polarizing reflection layer or a release sheet. Solvents for coating solutions include amides (eg, N, N-dimethylformamide), sulfoxides (eg, dimethyl sulfoxide), heterocyclic compounds (eg, pyridine), hydrocarbons (eg, benzene, hexane, cyclohexane), alkyl halides (Eg, chloroform, dichloromethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane), alkyl alcohols (Eg, methanol, ethanol, propanol). Two or more kinds of solvents may be mixed and used. Among the above, alkyl halides, esters, ketones and mixed solvents thereof are preferable.
As the coating solution for forming the thermoplastic weld layer, a commercially available composition as it is as a heat sealant, or a solution dissolved in a solvent or a solution diluted with a solvent can be used.
＜＜ハーフミラーの製造方法＞＞
　本発明のハーフミラーは、各層を接着層を用いて接着させることにより製造してもよく、成形樹脂層の射出成形等による製造と同時に、高Ｒｅ位相差膜または偏光反射板等を成形樹脂層のいずれか一方の表面に設け、これにさらに他の層を接着層を用いて接着させることにより製造してもよい。 << Method of manufacturing half mirror >>
The half mirror of the present invention may be manufactured by adhering each layer using an adhesive layer, and at the same time as manufacturing of a molded resin layer by injection molding or the like, a high Re retardation film or a polarizing reflector is formed as a molded resin layer. It may be produced by providing on one of the surfaces and further bonding another layer to the surface using an adhesive layer.
　高Ｒｅ位相差膜として第１の高Ｒｅ位相差膜のみを含むハーフミラーは、例えば、以下のいずれかの手順で得ることができる。
　成形樹脂層の一方の主表面側に偏光反射板、他方の主表面側に第１の高Ｒｅ位相差膜を、接着層を用いて接着させる；成形樹脂層の作製と同時に成形樹脂層の一方の主表面側に偏光反射板を設け、他方の主表面側に接着層を用いて第１の高Ｒｅ位相差膜を接着させる；成形樹脂層の作製と同時に成形樹脂層の一方の主表面側に第１の高Ｒｅ位相差膜を設け、他方の主表面側に接着層を用いて偏光反射板を接着させる；成形樹脂層の作製と同時に成形樹脂層の一方の主表面側に偏光反射板、他方の主表面側に第１の高Ｒｅ位相差膜を設ける。 A half mirror including only the first high Re retardation film as the high Re retardation film can be obtained, for example, by any of the following procedures.
Adhering a polarizing reflector on one main surface side of the molded resin layer and a first high Re retardation film on the other main surface side using an adhesive layer; one of the molded resin layers simultaneously with the production of the molded resin layer A polarizing reflector is provided on the main surface side of the first, and the first high Re retardation film is adhered to the other main surface side using an adhesive layer; one main surface side of the molded resin layer simultaneously with the production of the molded resin layer The first high-Re retardation film is provided on the other main surface, and the polarizing reflector is adhered to the other main surface side by using an adhesive layer; The first high Re retardation film is provided on the other main surface side.
　また、高Ｒｅ位相差膜として第１の高Ｒｅ位相差膜および第２の高Ｒｅ位相差膜を含むハーフミラーは、例えば、以下のいずれかの手順で得ることができる。
　成形樹脂層の一方の主表面側に第１の高Ｒｅ位相差膜、他方の主表面側に第２の高Ｒｅ位相差膜を、接着層を用いて接着させ、さらに第２の高Ｒｅ位相差膜の成形樹脂層が接着していない表面側に偏光反射板を接着層を用いて接着させる；成形樹脂層の作製と同時に成形樹脂層の一方の主表面側に第２の高Ｒｅ位相差膜を設け、得られた成形体の第２の高Ｒｅ位相差膜側に接着層を用いて接着させる。その後、成形樹脂層の他方の主表面側に第１の高Ｒｅ位相差膜を接着層を用いて接着させる；成形樹脂層の作製と同時に成形樹脂層の一方の主表面側に第１の高Ｒｅ位相差膜を設け、他方の主表面側に偏光反射板、第２の高Ｒｅ位相差膜をこの順でそれぞれ接着層を用いて接着させる；成形樹脂層の作製と同時に成形樹脂層の一方の主表面側に第１の高Ｒｅ位相差膜、他方の主表面側に第２の高Ｒｅ位相差膜を設け、その後、得られた成形体の第２の高Ｒｅ位相差膜側に接着層を用いて接着させる。 Moreover, the half mirror including the first high Re phase difference film and the second high Re phase difference film as the high Re phase difference film can be obtained by any of the following procedures, for example.
A first high Re phase difference film is adhered to one main surface side of the molded resin layer, and a second high Re phase difference film is adhered to the other main surface side using an adhesive layer, and further, a second high Re level is obtained. A polarizing reflector is adhered to the surface side of the retardation film on which the molded resin layer is not adhered by using an adhesive layer; simultaneously with the production of the molded resin layer, a second high Re phase difference is formed on one main surface side of the molded resin layer. A film is provided and adhered to the second high Re retardation film side of the obtained molded body using an adhesive layer. Thereafter, a first high Re retardation film is adhered to the other main surface side of the molded resin layer using an adhesive layer; simultaneously with the production of the molded resin layer, the first high Re film is formed on one main surface side of the molded resin layer. An Re retardation film is provided, and a polarizing reflector and a second high Re retardation film are adhered in this order using an adhesive layer on the other main surface side; one of the molded resin layers simultaneously with the production of the molded resin layer A first high-Re phase difference film is provided on the main surface side, and a second high-Re phase difference film is provided on the other main surface side, and then bonded to the second high-Re phase difference film side of the obtained molded body. Adhere using layers.
＜射出成形＞
　成形樹脂層は射出成形で製造することが好ましい。射出成形は樹脂を加熱溶融させたのち、溶融樹脂を金型内に加圧注入充填し、固化あるいは硬化して成形品を得る方法である。金型内とは金型により形成されている空間の中を意味する。通常は雄型と雌型の２枚の型により空間が形成されていればよい。 <Injection molding>
The molded resin layer is preferably manufactured by injection molding. Injection molding is a method in which a resin is heated and melted, and then the molten resin is injected into a mold under pressure and solidified or cured to obtain a molded product. The inside of the mold means a space formed by the mold. Usually, the space only needs to be formed by two molds, a male mold and a female mold.
　溶融樹脂を金型内に加圧注入充填する際の射出速度は１ｍｍ／秒～５０ｍｍ／秒であることが好ましく、５ｍｍ／秒～３０ｍｍ／秒であることがより好ましい。
　射出成形は、金型内で溶融樹脂が加熱および加圧された後、冷却されることにより行われる。
　加熱温度（金型温度：金型内面の表面温度）は５０℃～１５０℃であればよく、８０℃～１３０℃が好ましい。５０℃～１５０℃の温度範囲にすることで、溶融樹脂を金型内に加圧注入充填する際のヒケ、バリ、またはフローマークなどの発生を抑えることができ、寸法の安定した成形樹脂層を得ることができる。加圧は、０．０１ＭＰａ～１．０ＭＰａであればよく、０．０５ＭＰａ～０．５ＭＰａが好ましく、０．１ＭＰａ～０．３ＭＰａがより好ましい。加熱および加圧の時間は１秒から３００秒が好ましく、１０秒から１２０秒がより好ましい。 The injection speed when the molten resin is pressure-injected and filled into the mold is preferably 1 mm / second to 50 mm / second, and more preferably 5 mm / second to 30 mm / second.
Injection molding is performed by cooling the molten resin after it is heated and pressurized in the mold.
The heating temperature (mold temperature: surface temperature of the mold inner surface) may be 50 ° C. to 150 ° C., preferably 80 ° C. to 130 ° C. By setting the temperature range to 50 ° C. to 150 ° C., it is possible to suppress the occurrence of sink marks, burrs, flow marks, etc. when the molten resin is injected into the mold under pressure, and the molded resin layer has a stable dimension. Can be obtained. The pressurization may be from 0.01 MPa to 1.0 MPa, preferably from 0.05 MPa to 0.5 MPa, more preferably from 0.1 MPa to 0.3 MPa. The heating and pressurizing time is preferably 1 to 300 seconds, more preferably 10 to 120 seconds.
　冷却は室温以下にすることが好ましく、具体的には１０℃～３０℃にすればよい。冷却の前には加圧を行うことが好ましい。さらに冷却時は加圧状態が維持されていることが好ましい。一般に、金型温度を高くすると冷却までの時間が長くなるため、成形サイクルが長くなる問題がある。そこで、金型内面を短時間で冷却することが好ましい。金型内面は、成形樹脂層の耐擦過傷性の点から、１℃～１００℃／秒で冷却されることが好ましい。この金型内面の冷却速度は、３０℃～９０℃／秒がより好ましく、４０℃～８０℃／秒が更に好ましい。
　射出成形は、射出成形機により行うことができる。射出成形機は金型または金型を設置する部位のほか、射出機構、温度制御機構、型締機構などを有していればよい。 Cooling is preferably performed at room temperature or lower, specifically 10 ° C. to 30 ° C. It is preferable to pressurize before cooling. Furthermore, it is preferable that the pressurized state is maintained during cooling. In general, when the mold temperature is raised, the time until cooling becomes longer, which causes a problem that the molding cycle becomes longer. Therefore, it is preferable to cool the inner surface of the mold in a short time. The inner surface of the mold is preferably cooled at 1 ° C. to 100 ° C./second from the viewpoint of scratch resistance of the molded resin layer. The cooling rate of the inner surface of the mold is more preferably 30 ° C. to 90 ° C./second, and further preferably 40 ° C. to 80 ° C./second.
Injection molding can be performed by an injection molding machine. The injection molding machine may have an injection mechanism, a temperature control mechanism, a mold clamping mechanism, and the like in addition to the mold or the part where the mold is installed.
［金型］
　金型は通常、二枚組となっており、二枚を型締めすることにより上記空間が形成される。二枚のいずれかが固定盤であり、他方が可動盤であればよい。またいずれかが雌型であり、他方が雄型であればよい。雌型が固定盤であっても雄型が固定盤であってもよく、雌型が固定盤であることが好ましい。 [Mold]
The mold is usually a set of two, and the space is formed by clamping the two. Any one of the two plates may be a fixed platen and the other may be a movable platen. One of them may be a female mold and the other may be a male mold. The female die may be a fixed platen or the male die may be a fixed platen, and the female die is preferably a fixed platen.
＜インモールド成形またはインサート成形＞
　成形樹脂層の作製と同時に偏光反射板、第１の高Ｒｅ位相差膜、または第２の高Ｒｅ位相差膜のいずれか１つ以上（以下「偏光反射板または高Ｒｅ位相差膜等」ということがある）を設ける方法としては、一般的にインモールド成形またはインサート成形として知られる方法を用いることができる。いずれを用いるかは特に限定されず、偏光反射板はインモールド成形、高Ｒｅ位相差膜はインサート成形で設けられることが好ましい。 <In-mold molding or insert molding>
Simultaneously with the production of the molded resin layer, at least one of the polarizing reflector, the first high Re retardation film, and the second high Re retardation film (hereinafter referred to as “polarizing reflector or high Re retardation film”). In some cases, a method generally known as in-mold molding or insert molding can be used. Which is used is not particularly limited, and it is preferable that the polarizing reflector is provided by in-mold molding, and the high Re retardation film is provided by insert molding.
　インモールド成形では、射出成形を行う際に、偏光反射板または高Ｒｅ位相差膜等および基材フィルムを含む成形用シートが金型に挟み込まれた状態、例えば、成形用シートが二枚の金型に挟み込まれた状態とし、射出成形と同時に金型内で偏光反射板または高Ｒｅ位相差膜等を射出成形品表面に接着させる。射出成形の際に溶融樹脂が金型内に注入されて、基材フィルム、偏光反射板または高Ｒｅ位相差膜等、および溶融樹脂がこの順となるように配置すればよい。なお、熱可塑性溶着層を有する成形用シートを用いる場合は、基材フィルム、偏光反射板または高Ｒｅ位相差膜等、熱可塑性溶着層および溶融樹脂がこの順となるように配置する。その後、得られた成形樹脂層、偏光反射板または高Ｒｅ位相差膜等、および基材フィルムを含む成形体から基材フィルムを剥離する。インモールド成形では、金型内にロール状の成形用シートを送り込み、順次成形用シートの必要部位を挟み込んでハーフミラーを製造することができる。 In in-mold molding, when injection molding is performed, a state in which a molding sheet including a polarizing reflector or a high Re retardation film and a base film is sandwiched between molds, for example, a molding sheet is a two-sheet mold. In a state of being sandwiched between the molds, a polarizing reflector or a high Re retardation film is adhered to the surface of the injection molded product in the mold simultaneously with the injection molding. The molten resin is injected into the mold during the injection molding, and the base film, the polarizing reflector or the high Re retardation film, and the molten resin may be arranged in this order. When a molding sheet having a thermoplastic weld layer is used, the thermoplastic weld layer and the molten resin such as a base film, a polarizing reflector, or a high Re retardation film are arranged in this order. Thereafter, the base film is peeled from the obtained molded resin layer, a polarizing reflector, a high Re retardation film, and the like, and a molded body including the base film. In in-mold molding, a half mirror can be manufactured by feeding a roll-shaped molding sheet into a mold and sequentially sandwiching necessary portions of the molding sheet.
　インサート成形は、射出成形を行う際に偏光反射板または高Ｒｅ位相差膜等を含む成形用シートが金型に挟み込まれた状態、例えば、成形用シートが二枚の金型に挟み込まれた状態とし、射出成形と同時に金型内で、偏光反射板または高Ｒｅ位相差膜等を射出成形品表面に接着させる。成形用シートが熱可塑性溶着層を有する場合は、偏光反射板または高Ｒｅ位相差膜等、熱可塑性溶着層および溶融樹脂がこの順となるように配置する。インサート成形では実質的に成形用シート全体が完成品の一部となる。 Insert molding is a state in which a molding sheet including a polarizing reflector or a high Re retardation film is sandwiched between molds when performing injection molding, for example, a state in which a molding sheet is sandwiched between two molds. At the same time as the injection molding, a polarizing reflector or a high Re retardation film is adhered to the surface of the injection molded product in the mold. When the molding sheet has a thermoplastic weld layer, the thermoplastic weld layer and the molten resin, such as a polarizing reflector or a high Re retardation film, are arranged in this order. In insert molding, substantially the entire molding sheet is part of the finished product.
　成形用シートが金型に挟み込まれた状態とする際には、成形用シートを金型の内面に接触させておくことが好ましい。成形用シートの金型の内面への接触は、成形用シートの少なくとも一部で達成されていればよく、金型の対応する面積の実質的に全面で達成されていることが好ましい。すなわち、成形用シートの対応する面積は全面で密着していることが好ましい。接触は、単に転写シートを金型上に配置することにより達成されていてもよく、または、接触を達成する手段が講じられていてもよい。接触を達成する手段としては、真空吸引などが挙げられる。真空吸引については、例えば特開平１０－２６４２０１号公報を参照することができる。 When the molding sheet is sandwiched between molds, it is preferable that the molding sheet is in contact with the inner surface of the mold. The contact of the molding sheet with the inner surface of the mold only needs to be achieved on at least a part of the molding sheet, and is preferably achieved on substantially the entire area corresponding to the mold. That is, it is preferable that the corresponding area of the molding sheet is in close contact with the entire surface. Contact may be achieved simply by placing the transfer sheet on the mold, or means may be taken to achieve contact. Examples of means for achieving the contact include vacuum suction. For vacuum suction, reference can be made, for example, to JP-A-10-264201.
　成形樹脂層を成形後、他の部材を接着させる場合は、上記射出成形で得られる成形体を金型から取り外したあと、接着させればよい。インモールド成形で得られた成形体から基材フィルムを剥離する場合、基材フィルムの剥離は光学機能層の接着の前であっても後であってもよい。 When other members are bonded after molding the molded resin layer, the molded body obtained by the injection molding may be removed from the mold and then bonded. When the base film is peeled from the molded body obtained by in-mold molding, the base film may be peeled before or after adhesion of the optical functional layer.
［成形用シート］
　成形用シートは、偏光反射板、第１の高Ｒｅ位相差膜、および第２の高Ｒｅ位相差膜のいずれか１つ以上を含むことが好ましい。成形用シートは、熱可塑性溶着層を含んでいてもよい。また、成形用シートは、基材フィルムを含んでいてもよい。 [Sheet for molding]
The molding sheet preferably includes one or more of a polarizing reflector, a first high Re retardation film, and a second high Re retardation film. The molding sheet may include a thermoplastic welding layer. Moreover, the sheet | seat for shaping | molding may contain the base film.
　成形用シートが熱可塑性溶着層を含む場合、成形用シートの熱可塑性溶着層の成形樹脂層（溶融樹脂）への接着により、偏光反射板または高Ｒｅ位相差膜等が成形樹脂層と一体になった樹脂ミラーを得ることができる。熱可塑性溶着層は成形用シートの最外層にあることが好ましい。 When the molding sheet includes a thermoplastic welding layer, the polarizing reflector or the high Re retardation film is integrated with the molding resin layer by adhering the thermoplastic welding layer of the molding sheet to the molding resin layer (molten resin). A resin mirror can be obtained. The thermoplastic weld layer is preferably in the outermost layer of the molding sheet.
　成形用シートの最外層の表面、例えば熱可塑性溶着層の表面には、運搬等の際の保護のために保護層などが設けられていてもよく、成形用シートとしての使用時に保護層を剥離して用いてもよい。 The surface of the outermost layer of the molding sheet, for example, the surface of the thermoplastic welding layer, may be provided with a protective layer for protection during transportation, etc., and the protective layer is peeled off when used as a molding sheet May be used.
（転写シート）
　特に、偏光反射板を設けるための成形用シートとしては、転写シートを用いることができる。
　成形樹脂層の射出成形において偏光反射板を成形樹脂層上に設けるために転写シートを用いることができる。転写シートは板状またはフィルム状であればよい。転写シートはロール状になっていてもよい。
　転写シートの厚みは１．０μｍ～３００μｍであればよく、５．０μｍ～２００μｍであることが好ましい。転写シートの厚みを１．０μｍ～３００μｍとすることにより、シワを発生させることなく成形することができる。
　転写シートは、常温下での伸長伸びが５％～３００％であることが好ましく、１０％～２５０％であることがより好ましく、２０％～２００％であることがさらに好ましい。引張伸びは、薄いプラスチックシートの引張試験（ＡＳＴＭＤ８８２）に準じて測定することができる。 (Transfer sheet)
In particular, a transfer sheet can be used as a molding sheet for providing a polarizing reflector.
In the injection molding of the molded resin layer, a transfer sheet can be used for providing the polarizing reflector on the molded resin layer. The transfer sheet may be a plate or a film. The transfer sheet may be in the form of a roll.
The thickness of the transfer sheet may be 1.0 μm to 300 μm, preferably 5.0 μm to 200 μm. By setting the thickness of the transfer sheet to 1.0 μm to 300 μm, it can be formed without generating wrinkles.
The transfer sheet has an elongation at room temperature of preferably 5% to 300%, more preferably 10% to 250%, and even more preferably 20% to 200%. The tensile elongation can be measured according to a thin plastic sheet tensile test (ASTM D882).
　転写シートは偏光反射板を含む。転写シートは熱可塑性溶着層を含むことが好ましい。転写シートは、基材フィルム、離型層、配向層、保護層、接着層などの他の層を含んでいてもよい。偏光反射板および熱可塑性溶着層は、直接接していても、両者間に他の層があってもよい。
　転写シートとしては、上述のように作製された偏光反射板をそのまま用いることができる。作製の際に仮支持体を有するものは、仮支持体を基材フィルムとして、そのまま用いることができる。熱可塑性溶着層を含む転写シートは、偏光反射板上に、通常は偏光反射板の表面に、熱可塑性溶着層を形成することにより製造することができる。熱可塑性溶着層は、熱可塑性樹脂を含む塗布液を偏光反射板上に塗布して乾燥させること、または熱可塑性溶着層が形成された離型シートから熱可塑性溶着層を偏光反射板上に転写することにより作製することができる。 The transfer sheet includes a polarizing reflector. The transfer sheet preferably includes a thermoplastic weld layer. The transfer sheet may include other layers such as a base film, a release layer, an orientation layer, a protective layer, and an adhesive layer. The polarizing reflector and the thermoplastic welding layer may be in direct contact with each other or there may be other layers between them.
As the transfer sheet, the polarizing reflector produced as described above can be used as it is. What has a temporary support body in the case of preparation can use a temporary support body as a base film as it is. A transfer sheet including a thermoplastic welding layer can be produced by forming a thermoplastic welding layer on a polarizing reflector, usually on the surface of the polarizing reflector. The thermoplastic welding layer is obtained by applying a coating solution containing a thermoplastic resin on the polarizing reflector and drying it, or transferring the thermoplastic welding layer from the release sheet on which the thermoplastic welding layer is formed onto the polarizing reflector. It can produce by doing.
（基材フィルム）
　成形用シートは基材フィルムを含んでいてもよい。特に転写シートは基材フィルムを含むことが好ましい。
　基材フィルムとしては、液晶組成物を塗布して層形成するための仮支持体と同様の材料を用いることができる。好ましい例としては、ポリエチレンテレフタレートフィルムを挙げることができる。液晶組成物を塗布して層形成するための仮支持体がそのまま転写シートの基材フィルムとなっていることが好ましい。転写シートは偏光反射板形成時に用いられた配向層を含んでいてもよく、ハーフミラーの製造方法において、基材フィルムが剥離される場合、配向層も同時に剥離されてもよく、されなくてもよい。
　基材フィルムの厚みは、通常、５．０～２００μｍ程度であり、好ましくは、２０～１００μｍ程度であればよい。 (Base film)
The molding sheet may include a base film. In particular, the transfer sheet preferably includes a base film.
As the base film, the same material as the temporary support for applying the liquid crystal composition to form a layer can be used. A preferred example is a polyethylene terephthalate film. It is preferable that the temporary support for forming a layer by applying the liquid crystal composition is the base film of the transfer sheet as it is. The transfer sheet may include an alignment layer used at the time of forming the polarizing reflector, and when the base film is peeled off in the half mirror manufacturing method, the orientation layer may or may not be peeled off at the same time. Good.
The thickness of the base film is usually about 5.0 to 200 μm, preferably about 20 to 100 μm.
（離型層）
　成形用シート、特に転写シートは離型層を含んでいてもよい。離型層は基材フィルムの表面に設けられ、基材フィルムと偏光反射板または高Ｒｅ位相差膜等との間に配置されて、基材フィルムと偏光反射板または高Ｒｅ位相差膜等との分離を容易にするための層であり、基材フィルムが剥離されるときは、基材フィルムとともに剥離される。
　離型層は、基材フィルムの全面を被覆していてもよいし、基材フィルムの一部に設けられるものであってもよい。通常は、剥離性を考慮して、基材フィルムの全面を被覆していることが好ましい。 (Release layer)
The molding sheet, particularly the transfer sheet, may include a release layer. The release layer is provided on the surface of the base film, and is disposed between the base film and the polarizing reflector or the high Re retardation film. It is a layer for facilitating separation, and when the base film is peeled off, it is peeled off together with the base film.
The release layer may cover the entire surface of the base film, or may be provided on a part of the base film. Usually, it is preferable to cover the entire surface of the base film in consideration of peelability.
　離型層は、シリコーン樹脂、フッ素系樹脂、アクリル系樹脂（例えば、アクリル－メラミン系樹脂が含まれる。）、ポリエステル系樹脂、ポリオレフィン系樹脂、ポリスチレン系樹脂、ポリウレタン系樹脂、セルロース系樹脂、塩化ビニル－酢酸ビニル系共重合体樹脂、硝化綿などの熱可塑性樹脂、この熱可塑性樹脂を形成するモノマーの共重合体、あるいはこれらの樹脂を（メタ）アクリル酸やウレタンで変性したものを、単独でまたは複数を混合した樹脂組成物を用いて形成することができる。なかでも、アクリル系樹脂、ポリエステル系樹脂、ポリオレフィン系樹脂、ポリスチレン系樹脂、これらの樹脂を形成するモノマーの共重合体、及びこれらをウレタン変性したものが好ましい。より具体的には、アクリル－メラミン系樹脂単独、アクリル－メラミン系樹脂含有組成物、ポリエステル系樹脂とエチレン及びアクリル酸の共重合体をウレタン変性したものとを混合した樹脂組成物、アクリル系樹脂とスチレン及びアクリルとの共重合体のエマルションとを混合した樹脂組成物などが挙げられる。これらのうち、アクリル－メラミン系樹脂単独又はアクリル－メラミン系樹脂を５０質量％以上含有する組成物で離型層を構成することが特に好ましい。離型層の厚みは、通常、０．０１～５．０μｍ程度であればよく、好ましくは、０．０５～３．０μｍ程度であればよい。 The release layer is made of silicone resin, fluorine resin, acrylic resin (for example, acrylic-melamine resin), polyester resin, polyolefin resin, polystyrene resin, polyurethane resin, cellulose resin, chloride resin, Vinyl-vinyl acetate copolymer resins, thermoplastic resins such as nitrified cotton, copolymers of monomers that form this thermoplastic resin, or those modified with (meth) acrylic acid or urethane alone It can be formed by using a resin composition in which two or more are mixed. Among these, acrylic resins, polyester resins, polyolefin resins, polystyrene resins, copolymers of monomers forming these resins, and those obtained by urethane modification thereof are preferable. More specifically, an acrylic-melamine resin alone, an acrylic-melamine resin-containing composition, a resin composition in which a polyester resin and a copolymer of ethylene and acrylic acid are modified with urethane, an acrylic resin And a resin composition in which an emulsion of a copolymer of styrene and acrylic is mixed. Among these, it is particularly preferable that the release layer is composed of an acrylic-melamine resin alone or a composition containing 50% by mass or more of the acrylic-melamine resin. The thickness of the release layer is usually about 0.01 to 5.0 μm, preferably about 0.05 to 3.0 μm.
＜＜ハーフミラーの用途＞＞
　ハーフミラーは、偏光反射板の光学特性に応じて、様々な用途に用いることができる。用途の例としては、車両用（車載用）ミラー、光学レンズ、アイウェア用光学部材などが挙げられる。これらのうち、車両用ミラーが好ましい。 << Use of half mirror >>
The half mirror can be used for various applications depending on the optical characteristics of the polarizing reflector. Examples of applications include vehicle (on-vehicle) mirrors, optical lenses, eyewear optical members, and the like. Of these, vehicle mirrors are preferred.
＜＜画像表示機能付きミラー＞＞
　本発明のハーフミラーを用いて、画像表示機能付きミラーを作製することができる。画像表示機能付きミラーはハーフミラーおよび画像表示装置を含む。画像表示機能付きミラーにおいて、観察面、成形樹脂層、偏光反射板、および画像表示装置はこの順で配置される。画像表示機能付きミラーにおいて、画像表示装置およびハーフミラーは、互いに直接接していてもよく、その間に空気層が存在してもよく、または接着層を介して直接接着されていてもよい。 << Mirror with image display function >>
A mirror with an image display function can be manufactured using the half mirror of the present invention. The mirror with an image display function includes a half mirror and an image display device. In the mirror with an image display function, the observation surface, the molded resin layer, the polarizing reflector, and the image display device are arranged in this order. In the mirror with an image display function, the image display device and the half mirror may be in direct contact with each other, an air layer may be present therebetween, or may be directly bonded via an adhesive layer.
　画像表示機能付きミラーにおいては、画像表示装置の画像表示部の面積と同じ表面積を有するハーフミラーを用いてもよく、画像表示装置の画像表示部の面積よりも大きいか、または小さい表面積を有するハーフミラーを用いてもよい。これらの関係を選択することにより、ミラーの全面に対する画像表示部表面の割合や位置を調整することができる。なお、本明細書において、「表面積」とは、板状またはフィルム状の部材のおもて面および裏面のいずれか一方の面積をいう。 In the mirror with an image display function, a half mirror having the same surface area as the area of the image display unit of the image display device may be used, and the half mirror having a surface area larger or smaller than the area of the image display unit of the image display device. A mirror may be used. By selecting these relationships, it is possible to adjust the ratio and position of the surface of the image display unit with respect to the entire surface of the mirror. In the present specification, the “surface area” refers to the area of either the front surface or the back surface of a plate-like or film-like member.
　１／４波長板を含むハーフミラーを用いる場合、画像表示機能付きミラーにおいて、１／４波長板の遅相軸は、画像が最も明るくなるように調整されていることが好ましい。すなわち、特に直線偏光により画像表示している画像表示装置に対し、上記直線偏光を最もよく透過させるように上記直線偏光の偏光方向（透過軸）と１／４波長板の遅相軸との関係が調整されていることが好ましい。例えば、１／４波長板の場合、上記透過軸と遅相軸とは４５°の角度をなしていることが好ましい。直線偏光により画像表示している画像表示装置から出射した光は１／４波長板を透過後、右および左のいずれかのセンスの円偏光となっている。後述の円偏光反射層は、上記のセンスの円偏光を透過する捩れ方向を有するコレステリック液晶層で構成されていればよい。 When a half mirror including a quarter wavelength plate is used, in the mirror with an image display function, it is preferable that the slow axis of the quarter wavelength plate is adjusted so that the image is brightest. That is, the relationship between the polarization direction of the linearly polarized light (transmission axis) and the slow axis of the quarter-wave plate so that the linearly polarized light is transmitted best, particularly for an image display device displaying an image by linearly polarized light. Is preferably adjusted. For example, in the case of a quarter wavelength plate, it is preferable that the transmission axis and the slow axis form an angle of 45 °. The light emitted from the image display device displaying an image by linearly polarized light is circularly polarized light of either right or left sense after passing through the quarter wavelength plate. The circularly polarized light reflecting layer described later only needs to be composed of a cholesteric liquid crystal layer having a twist direction that transmits the circularly polarized light of the above-described sense.
　画像表示装置と円偏光反射層との間に１／４波長板を含むことによって、画像表示装置からの光を円偏光に変換して円偏光反射層に入射させることが可能となる。そのため、円偏光反射層において反射されて画像表示装置側に戻る光を大幅に減らすことができ、明るい画像の表示が可能となる。 By including a quarter-wave plate between the image display device and the circularly polarized reflection layer, it becomes possible to convert the light from the image display device into circularly polarized light and make it incident on the circularly polarized reflection layer. Therefore, the light reflected by the circularly polarized light reflection layer and returning to the image display device side can be greatly reduced, and a bright image can be displayed.
＜画像表示装置＞
　画像表示装置は直線偏光を出射して（発光して）画像を形成する画像表示装置であることが好ましい。高Ｒｅ位相差膜の遅相軸は画像表示装置が出射する直線偏光の偏光方向と３０°～６０°の角度をなすように本発明のハーフミラーを配置して画像表示機能付きミラーを作製することにより、偏光サングラスを介して観察しても明暗ムラまたは色ムラのない画像を観測することができる。 <Image display device>
The image display device is preferably an image display device that emits (emits light) linearly polarized light to form an image. The half mirror of the present invention is arranged so that the slow axis of the high Re retardation film forms an angle of 30 ° to 60 ° with the polarization direction of the linearly polarized light emitted from the image display device, thereby producing a mirror with an image display function. Thus, an image having no brightness unevenness or color unevenness can be observed even when observed through polarized sunglasses.
　画像表示装置は、液晶表示装置であればよい。また、本発明のハーフミラーは、バックライトとして連続的な発光スペクトルを与えるバックライトを有する画像表示装置と組み合わせて用いることにより、偏光サングラスを介して観察した画像における明暗ムラまたは色ムラを解消することができる。バックライトとしては白色ＬＥＤ（白色発光ダイオード）が好ましい。ここで、連続的な発光スペクトルとは、例えば、発光を実質的に示さない波長域がない可視光領域の発光スペクトル（例えば太陽光の可視光領域のスペクトル）を意味する。連続的な発光スペクトルを与えるバックライトの例には、白色ＬＥＤが含まれ、蛍光灯などのように可視光波長領域において特定波長にピークを有する不連続な発光スペクトルを示すものは含まれない。 The image display device may be a liquid crystal display device. In addition, the half mirror of the present invention eliminates light / dark unevenness or color unevenness in an image observed through polarized sunglasses by using it in combination with an image display device having a backlight that gives a continuous emission spectrum as a backlight. be able to. A white LED (white light emitting diode) is preferable as the backlight. Here, the continuous emission spectrum means, for example, an emission spectrum in the visible light region (eg, a spectrum in the visible light region of sunlight) having no wavelength region that does not substantially emit light. Examples of the backlight that gives a continuous emission spectrum include white LEDs, and those that show a discontinuous emission spectrum having a peak at a specific wavelength in the visible light wavelength region, such as a fluorescent lamp, are not included.
　液晶表示装置は透過型であっても反射型であってもよく、特に、透過型であることが好ましい。液晶表示装置は、ＩＰＳ（In Plane Switching）モード、ＦＦＳ（Fringe Field Switching)モード、ＶＡ（Vertical Alignment）モード、ＥＣＢ（Electrically Controlled Birefringence）モード、ＳＴＮ（Super Twisted Nematic）モード、ＴＮ（Twisted Nematic）モード、ＯＣＢ（Optically Compensated Bend）モードなどのいずれの液晶表示装置であってもよい。 The liquid crystal display device may be a transmissive type or a reflective type, and is particularly preferably a transmissive type. Liquid crystal display devices include IPS (In-Plane Switching) mode, FFS (Fringe Field Switching) mode, VA (Vertical Alignment) mode, ECB (Electrically Controlled Birefringence) mode, STN (Super Twisted Nematic) mode, and TN (Twisted Nematic) mode. Any liquid crystal display device such as an OCB (Optically Compensated Bend) mode may be used.
　画像表示装置の画像表示部に示される画像は、静止画であっても動画であっても、単なる文字情報であってもよい。また白黒などのモノカラー表示であってもよく、マルチカラー表示であってもよく、フルカラー表示であってもよい。画像表示装置の画像表示部に示される画像の好ましい例としては、車載用のカメラで撮影された像が挙げられる。この像は動画であることが好ましい。 The image displayed on the image display unit of the image display device may be a still image, a moving image, or simply text information. Further, it may be a monochrome display such as black and white, a multi-color display, or a full-color display. A preferable example of the image displayed on the image display unit of the image display device is an image taken by a vehicle-mounted camera. This image is preferably a moving image.
　画像表示装置は、例えば、白表示時の発光スペクトルにおいて赤色光の発光ピーク波長λＲと、緑色光の発光ピーク波長λＧと、青色光の発光ピーク波長λＢとを示していればよい。このような発光ピーク波長を有することによりフルカラーの画像表示が可能である。λＲは５８０ｎｍ～７００ｎｍの範囲、好ましくは６１０ｎｍ～６８０ｎｍの範囲のいずれかの波長であればよい。λＧは５００ｎｍ～５８０ｎｍの範囲、好ましくは５１０ｎｍ～５５０ｎｍの範囲のいずれかの波長であればよい。λＢは４００ｎｍ～５００ｎｍの範囲、好ましくは４４０ｎｍ～４８０ｎｍの範囲のいずれかの波長であればよい。 For example, the image display device only needs to indicate the emission peak wavelength λR of red light, the emission peak wavelength λG of green light, and the emission peak wavelength λB of blue light in the emission spectrum during white display. By having such an emission peak wavelength, full-color image display is possible. λR may be any wavelength in the range of 580 nm to 700 nm, preferably in the range of 610 nm to 680 nm. λG may be any wavelength in the range of 500 nm to 580 nm, preferably in the range of 510 nm to 550 nm. λB may be any wavelength in the range of 400 nm to 500 nm, preferably in the range of 440 nm to 480 nm.
＜＜画像表示機能付きミラーの製法＞＞
　画像表示機能付きミラーは、画像表示装置の画像表示側に、上記ハーフミラーを配置して、画像表示装置とハーフミラーとを一体化することにより作製することができる。ハーフミラーは、観察面、成形樹脂層、偏光反射板、および画像表示装置がこの順となるように配置する。また、上述のように、ハーフミラーの第１の高Ｒｅ位相差膜の遅相軸が画像表示装置が出射する直線偏光の偏光方向と３０°～６０°の角度をなすように配置することが好ましく、４０°～５０°の角度をなすように配置することがより好ましい。この場合、第１の高Ｒｅ位相差膜および第２の高Ｒｅ位相差膜を含むハーフミラーを用いる場合、第１の高Ｒｅ位相差膜の遅相軸の方向および第２の高Ｒｅ位相差膜の遅相軸の方向が同じであるハーフミラーを用いることが好ましい。第１の高Ｒｅ位相差膜の遅相軸の方向および第２の高Ｒｅ位相差膜の遅相軸の方向が同じであることにより、画像ムラを効率的に低減することができる。例えば、両者の遅相軸の方向が同じものを用いることにより、それぞれの正面位相差が１５００ｎｍ以上３０００ｎｍ未満程度である場合であっても、画像ムラを低減することができる。また、第１の高Ｒｅ位相差膜の正面位相差と第２の高Ｒｅ位相差膜の正面位相差との差異が３０００ｎｍ以上ある場合は、両者の遅相軸の方向が異なっていても画像ムラを低減することができる。 << Manufacturing method of mirror with image display function >>
The mirror with an image display function can be manufactured by arranging the half mirror on the image display side of the image display device and integrating the image display device and the half mirror. The half mirror is arranged so that the observation surface, the molded resin layer, the polarizing reflector, and the image display device are in this order. Further, as described above, the slow axis of the first high Re retardation film of the half mirror may be arranged so as to form an angle of 30 ° to 60 ° with the polarization direction of the linearly polarized light emitted from the image display device. It is preferable to arrange them at an angle of 40 ° to 50 °. In this case, when a half mirror including the first high Re phase difference film and the second high Re phase difference film is used, the direction of the slow axis of the first high Re phase difference film and the second high Re phase difference It is preferable to use half mirrors having the same slow axis direction of the film. Since the direction of the slow axis of the first high Re retardation film and the direction of the slow axis of the second high Re retardation film are the same, image unevenness can be reduced efficiently. For example, by using those having the same slow axis direction, even if the front phase difference is about 1500 nm or more and less than 3000 nm, it is possible to reduce image unevenness. Further, when the difference between the front phase difference of the first high Re retardation film and the front phase difference of the second high Re retardation film is 3000 nm or more, the image can be obtained even if the slow axis directions of both are different. Unevenness can be reduced.
　画像表示装置とハーフミラーとの一体化は、フレームまたは蝶番での連結や、接着により行えばよい。例えば、画像表示機能付きミラーは、画像表示装置の画像表示面にハーフミラーを接着して作製することができる。接着は、成形樹脂層、偏光反射板、および画像表示装置がこの順になるように行う。画像表示装置とハーフミラーとの接着は上述の接着層を用いて行うことができ、高透明性接着剤転写テープを用いることが好ましい。 Integrating the image display device and the half mirror may be performed by connecting with a frame or a hinge or bonding. For example, a mirror with an image display function can be manufactured by adhering a half mirror to an image display surface of an image display device. Adhesion is performed so that the molded resin layer, the polarizing reflector, and the image display device are in this order. Adhesion between the image display device and the half mirror can be performed using the above-mentioned adhesive layer, and it is preferable to use a highly transparent adhesive transfer tape.
＜＜画像表示機能付きミラーの用途＞＞
　画像表示機能付きミラーの用途としては特に限定されない。例えば、防犯用ミラー、美容室または理容室のミラー等として用い、文字情報、静止画、動画などの画像を表示することができる。また、画像表示機能付きミラーは、車両用ルームミラーであってもよく、テレビ、パーソナルコンピューター、スマートフォン、携帯電話として用いられていてもよい。 << Use of mirror with image display function >>
The use of the mirror with an image display function is not particularly limited. For example, it can be used as a security mirror, a beauty salon or a barber mirror, and can display images such as character information, still images, and moving images. The mirror with an image display function may be a vehicle rearview mirror, and may be used as a television, a personal computer, a smartphone, or a mobile phone.
　画像表示機能付きミラーは車両用ルームミラーとして用いられることが特に好ましい。画像表示機能付きミラーは、ルームミラーとしての使用のため、フレーム、ハウジング、車両本体に取り付けるための支持アーム等を有していてもよい。あるいは、車両用画像表示機能付きミラーはルームミラーへの組み込み用に成形されたものであってもよい。上記の形状の車両用画像表示機能付きミラーにおいては、通常使用時に上下左右となる方向が特定できる。 The mirror with an image display function is particularly preferably used as a vehicle rearview mirror. The mirror with an image display function may have a frame, a housing, a support arm for attaching to the vehicle body, and the like for use as a rearview mirror. Alternatively, the vehicle image display function-equipped mirror may be formed for incorporation into a room mirror. In the vehicle-mounted image display function-equipped mirror having the above shape, it is possible to specify the vertical and horizontal directions during normal use.
　画像表示機能付きミラーを湾曲させて、観察面を凸曲面とすることにより、広角的に後方視野等を視認できるワイドミラーとすることも可能である。このような湾曲した観察面は湾曲したハーフミラーを用いて作製することができる。
　湾曲は、上下方向、左右方向、または上下方向と左右方向との両方にあればよい。また、湾曲は、曲率半径が５００ｍｍ～３０００ｍｍであればよい。１０００ｍｍ～２５００ｍｍであることがより好ましい。曲率半径は、断面で湾曲部分の外接円を仮定した場合の、この外接円の半径である。 By curving the mirror with an image display function and making the observation surface convex, it is possible to make a wide mirror that can visually recognize the rear visual field and the like in a wide angle. Such a curved observation surface can be produced using a curved half mirror.
The curve may be in the vertical direction, the horizontal direction, or both the vertical direction and the horizontal direction. In addition, the curvature may be a curvature radius of 500 mm to 3000 mm. More preferably, it is 1000 mm to 2500 mm. The radius of curvature is the radius of the circumscribed circle when the circumscribed circle of the curved portion is assumed in the cross section.
　以下に実施例を挙げて本発明をさらに具体的に説明する。以下の実施例に示す材料、試薬、物質量とその割合、操作等は本発明の趣旨から逸脱しない限り適宜変更することができる。従って、本発明の範囲は以下の実施例に限定されない。 The present invention will be described more specifically with reference to the following examples. The materials, reagents, amounts and ratios of substances, operations, and the like shown in the following examples can be appropriately changed without departing from the gist of the present invention. Therefore, the scope of the present invention is not limited to the following examples.
＜ハーフミラーの作製＞
　以下の材料および手順を表３に示すように用いて実施例１～２０、比較例１～４，参考例１～４のハーフミラーを作製した。 <Production of half mirror>
Half mirrors of Examples 1 to 20, Comparative Examples 1 to 4, and Reference Examples 1 to 4 were produced using the following materials and procedures as shown in Table 3.
［偏光反射板の作製］
（塗布液の調製）
　コレステリック液晶層形成用として、塗布液１、塗布液２、および塗布液３、並びに、１／４波長板用として塗布液４を下記表１に示す組成で調製した。 [Preparation of polarizing reflector]
(Preparation of coating solution)
For forming the cholesteric liquid crystal layer, the coating liquid 1, the coating liquid 2, and the coating liquid 3 and the coating liquid 4 for a quarter wavelength plate were prepared with the compositions shown in Table 1 below.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-C000002
　化合物２は特開２００５－９９２４８号公報に記載の方法で製造した。
Figure JPOXMLDOC01-appb-C000002
Compound 2 was produced by the method described in JP-A-2005-99248.
（円偏光反射板Ａの作製）
　仮支持体（１００ｍｍ×１５０ｍｍ）は東洋紡（株）製ＰＥＴフィルム（コスモシャインＡ４１００、厚み：１００μｍ）を使用し、ラビング処理（レーヨン布、圧力：０．１ｋｇｆ（０．９８Ｎ）、回転数：１０００ｒｐｍ、搬送速度：１０ｍ／ｍｉｎ、回数：１往復）を施した。塗布液１を、ワイヤーバーを用いてＰＥＴフィルムのラビングした表面に塗布後、乾燥させて３０℃のホットプレート上に置いた。次いでフュージョンＵＶシステムズ株式会社製無電極ランプ「Ｄバルブ」（６０ｍＷ／ｃｍ2）にて６秒間ＵＶ照射し、コレステリック液晶相を固定して、厚み３．５μｍのコレステリック液晶層を得た。得られた層の表面にさらに塗布液２および塗布液３を用いて同様の工程を繰り返し、３層のコレステリック液晶層の円偏光反射板Ａ（塗布液２の層：３．０μｍ、塗布液３の層：２．７μｍ）を得た。円偏光反射板Ａの透過スペクトルを分光光度計（日本分光株式会社製、Ｖ－６７０）で測定したところ、６３０ｎｍ、５４０ｎｍ、４５０ｎｍに反射ピークを有する透過スペクトルが得られた。 (Preparation of circularly polarized light reflector A)
The temporary support (100 mm × 150 mm) uses a PET film (Cosmo Shine A4100, thickness: 100 μm) manufactured by Toyobo Co., Ltd., and is rubbed (rayon cloth, pressure: 0.1 kgf (0.98 N), rotation speed: 1000 rpm. , Transport speed: 10 m / min, number of times: 1 reciprocation). The coating liquid 1 was applied to the rubbed surface of the PET film using a wire bar, then dried and placed on a 30 ° C. hot plate. Subsequently, UV irradiation was performed for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd. to fix the cholesteric liquid crystal phase to obtain a cholesteric liquid crystal layer having a thickness of 3.5 μm. The same process is further repeated on the surface of the obtained layer using the coating liquid 2 and the coating liquid 3, and a circularly polarizing reflector A having three cholesteric liquid crystal layers (layer of coating liquid 2: 3.0 μm, coating liquid 3 Layer: 2.7 μm). When the transmission spectrum of the circularly polarized light reflector A was measured with a spectrophotometer (manufactured by JASCO Corporation, V-670), transmission spectra having reflection peaks at 630 nm, 540 nm, and 450 nm were obtained.
（円偏光反射板Ｂ（１／４波長板を含む）の作製）
　塗布液４を、ワイヤーバーを用いてＰＥＴフィルムのラビングした表面に塗布後、乾燥させて３０℃のホットプレート上に置いた。次いでフュージョンＵＶシステムズ株式会社製無電極ランプ「Ｄバルブ」（６０ｍＷ／ｃｍ2）にて、６秒間ＵＶ照射し、液晶相を固定して、厚み０．８μｍの１／４波長板を得た。得られた層の表面にさらに塗布液１、塗布液２および塗布液３を用いて同様の工程を繰り返し、１／４波長板上に３層のコレステリック液晶層の円偏光反射板Ｂ（塗布液１の層：３．５μｍ、塗布液２の層：３．０μｍ、塗布液３の層：２．７μｍ）を得た。円偏光反射板Ｂの透過スペクトルをＶ－６７０にて測定したところ、６３０ｎｍ、５４０ｎｍ、４５０ｎｍに反射ピークを有する透過スペクトルが得られた。 (Production of circularly polarized light reflector B (including quarter-wave plate))
The coating liquid 4 was applied to the rubbed surface of the PET film using a wire bar, then dried and placed on a 30 ° C. hot plate. Subsequently, UV irradiation was carried out for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd., and the liquid crystal phase was fixed to obtain a quarter wavelength plate having a thickness of 0.8 μm. The same process is repeated using the coating liquid 1, the coating liquid 2 and the coating liquid 3 on the surface of the obtained layer, and a circularly polarizing reflector B (coating liquid) having three cholesteric liquid crystal layers on a quarter-wave plate. 1 layer: 3.5 μm, coating solution 2 layer: 3.0 μm, coating solution 3 layer: 2.7 μm). When the transmission spectrum of the circularly polarizing reflector B was measured with V-670, transmission spectra having reflection peaks at 630 nm, 540 nm, and 450 nm were obtained.
（直線偏光反射板の作製）
　特表平９－５０６８３７号公報に記載された方法に基づき、直線偏光反射板を作製した。２，６－ポリエチレンナフタレート（ＰＥＮ）とナフタレート７０／テレフタレート３０のコポリエステル（ｃｏＰＥＮ）とを、ジオールとしてエチレングリコールを用いて、標準ポリエステル樹脂合成釜において合成した。ＰＥＮとｃｏＰＥＮの単層フィルムを押出成形した後、約１５０℃において、延伸比５：１で延伸した。配向軸に関するＰＥＮの屈折率は、約１．８８、横断軸に関する屈折率は、１．６４、ｃｏＰＥＮフィルムの屈折率は、約１．６４となることを確認した。
　続いて、標準押出ダイを供給した５０スロット供給ブロックを用いて同時押出することにより、ＰＥＮとｃｏＰＥＮの交互の層の厚さを表２（１）に示す膜厚で形成した。上記を繰返して、表２（２）～（５）に示す膜厚のＰＥＮおよびｃｏＰＥＮの層を順に形成し、さらに（１）～（５）の層の形成を繰り返して各５０層ずつを計２５０層積層した。その後、延伸したフィルムを、エアーオーブン内において、約２３０℃で３０秒間熱硬化し、直線偏光反射板を得た。 (Production of linearly polarized light reflector)
A linearly polarized light reflecting plate was produced based on the method described in JP-T-9-506837. 2,6-polyethylene naphthalate (PEN) and naphthalate 70 / terephthalate 30 copolyester (coPEN) were synthesized in a standard polyester resin synthesis kettle using ethylene glycol as the diol. A single layer film of PEN and coPEN was extruded and then stretched at a stretch ratio of 5: 1 at about 150 ° C. It was confirmed that the refractive index of PEN with respect to the orientation axis was about 1.88, the refractive index with respect to the transverse axis was 1.64, and the refractive index of the coPEN film was about 1.64.
Then, the thickness of the alternating layer of PEN and coPEN was formed in the film thickness shown in Table 2 (1) by co-extrusion using a 50 slot supply block supplied with a standard extrusion die. By repeating the above, the PEN and coPEN layers having the thicknesses shown in Table 2 (2) to (5) were formed in order, and the formation of the layers (1) to (5) was further repeated to measure 50 layers each. 250 layers were laminated. Thereafter, the stretched film was thermally cured at about 230 ° C. for 30 seconds in an air oven to obtain a linearly polarized light reflector.
Figure JPOXMLDOC01-appb-T000003
Figure JPOXMLDOC01-appb-T000003
［仮支持体付き１／４波長板の作製］
　上記塗布液４を、ワイヤーバーを用いてＰＥＴフィルムのラビングした表面に塗布後、乾燥させて３０℃のホットプレート上に置いた。次いでフュージョンＵＶシステムズ株式会社製無電極ランプ「Ｄバルブ」（６０ｍＷ／ｃｍ2）にて、６秒間ＵＶ照射し、液晶相を固定して、厚み０．８μｍの仮支持体付き１／４波長板を得た。 [Preparation of quarter wave plate with temporary support]
The coating solution 4 was applied to a rubbed surface of a PET film using a wire bar, then dried and placed on a 30 ° C. hot plate. Next, UV irradiation was performed for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd., the liquid crystal phase was fixed, and a quarter-wave plate with a temporary support having a thickness of 0.8 μm. Got.
［光透過性基材（高Ｒｅ位相差膜）の作製］
　固有粘度０．６２ｄｌ／ｇのＰＥＴ樹脂ペレットを１３５℃で６時間減圧乾燥（１Ｔｏｒｒ（１３３Ｐａ））した後、押出機に供給し、２８５℃で溶解した。このポリマーを、ステンレス焼結体の濾材（公称濾過精度１０μｍ粒子９５％カット）で濾過し、口金よりシート状にして押し出した後、静電印加キャスト法を用いて表面温度３０℃のキャスティングドラムに巻きつけて冷却固化し、未延伸フィルムを作った。
　上記未延伸フィルムをテンター延伸機に導き、フィルムの端部をクリップで把持しながら、温度１２５℃の熱風ゾーンに導き、幅方向に延伸した。次に、幅方向に延伸された幅を保ったまま、温度２２５℃、３０秒間で処理し、さらに幅方向に３％の緩和処理を行い、表３に示す正面位相差を有する一軸配向の光透過性基材を得た。正面位相差はＡｘｏｍｅｔｒｉｃｓ社製のＡｘｏＳｃａｎを用いて測定した。 [Production of light-transmitting substrate (high Re retardation film)]
PET resin pellets having an intrinsic viscosity of 0.62 dl / g were dried under reduced pressure at 135 ° C. for 6 hours (1 Torr (133 Pa)), then supplied to an extruder and dissolved at 285 ° C. This polymer is filtered with a filter material of stainless sintered body (nominal filtration accuracy 10 μm particles 95% cut), extruded into a sheet form from the die, and then applied to a casting drum having a surface temperature of 30 ° C. using an electrostatic application casting method. It was wound and solidified by cooling to make an unstretched film.
The unstretched film was guided to a tenter stretching machine, and the end of the film was guided by a clip while being guided by a clip, and stretched in the width direction. Next, while maintaining the width stretched in the width direction, it was processed at a temperature of 225 ° C. for 30 seconds, and further subjected to a relaxation treatment of 3% in the width direction, and uniaxially oriented light having a front phase difference shown in Table 3 A permeable substrate was obtained. The front phase difference was measured using an AxoScan manufactured by Axometrics.
［光学機能層の作製］
（ハードコート層：ＨＣ）
　ＤＰＨＡ（日本化薬株式会社製）：５０質量部
　Ｉｒｇａｃｕｒｅ１８４（ＢＡＳＦジャパン株式会社製）：２．０質量部
　メチルエチルケトン：５０質量部
　上記塗布液を、ワイヤーバーを用いて正面位相差８０００ｎｍの光透過性基材上に塗布後、乾燥させて３０℃のホットプレート上に置いた。次いでフュージョンＵＶシステムズ株式会社製無電極ランプ「Ｄバルブ」（６０ｍＷ／ｃｍ2）にて６秒間ＵＶ照射し、厚み５．０μｍのハードコート層を形成した。 [Production of optical functional layer]
(Hard coat layer: HC)
DPHA (manufactured by Nippon Kayaku Co., Ltd.): 50 parts by mass Irgacure 184 (manufactured by BASF Japan Ltd.): 2.0 parts by mass Methyl ethyl ketone: 50 parts by mass Using the wire bar, a light transmission with a front phase difference of 8000 nm is used. After coating on the substrate, it was dried and placed on a 30 ° C. hot plate. Subsequently, UV irradiation was performed for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd. to form a hard coat layer having a thickness of 5.0 μm.
（防眩層：ＡＧ）
　ＤＰＨＡ（日本化薬株式会社製）：５０質量部
　ＳＸ－３５０（平均粒径３．５μｍ、屈折率１．５５、綜研化学株式会社製、３０％トルエン分散液、ポリトロン分散機にて１００００ｒｐｍで２０分分散後使用）：１０質量部
　Ｉｒｇａｃｕｒｅ１８４（ＢＡＳＦジャパン株式会社製）：２．０質量部
　トルエン：４０質量部
　上記塗布液を、ワイヤーバーを用いて正面位相差８０００ｎｍの光透過性基材上に塗布後、乾燥させて３０℃のホットプレート上に置いた。次いでフュージョンＵＶシステムズ株式会社製無電極ランプ「Ｄバルブ」（６０ｍＷ／ｃｍ2）にて６秒間ＵＶ照射し、厚み５μｍの防眩層を形成した。 (Anti-glare layer: AG)
DPHA (manufactured by Nippon Kayaku Co., Ltd.): 50 parts by mass SX-350 (average particle size 3.5 μm, refractive index 1.55, manufactured by Soken Chemical Co., Ltd., 30% toluene dispersion, Polytron disperser 20 at 10,000 rpm Use after dispersion): 10 parts by weight Irgacure 184 (BASF Japan Ltd.): 2.0 parts by weight Toluene: 40 parts by weight The above coating solution is applied onto a light-transmitting substrate having a front phase difference of 8000 nm using a wire bar. After coating, it was dried and placed on a 30 ° C. hot plate. Subsequently, UV irradiation was performed for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd. to form an antiglare layer having a thickness of 5 μm.
（反射防止層：ＡＲ）
　ＰＥＴＡ（商品名ＰＥＴ－３０）：（日本化薬株式会社製）：５０質量部
　ＫＥ－Ｐ３０（日本触媒株式会社製アモルファスシリカ粒子シーホスター、平均一次粒子径３００ｎｍ）：１０質量部
　Ｉｒｇａｃｕｒｅ１８４（ＢＡＳＦジャパン株式会社製）：２．０質量部
　酢酸ブチル：５０質量部
　上記塗布液を、ワイヤーバーを用いて正面位相差８０００ｎｍの光透過性基材上に塗布後、乾燥させて３０℃のホットプレート上に置いた。次いでフュージョンＵＶシステムズ株式会社製無電極ランプ「Ｄバルブ」（６０ｍＷ／ｃｍ2）にて６秒間ＵＶ照射し、厚み５．０μｍの反射防止層を形成した。 (Antireflection layer: AR)
PETA (trade name PET-30): (Nippon Kayaku Co., Ltd.): 50 parts by mass KE-P30 (Nippon Shokubai Co., Ltd. amorphous silica particle seahoster, average primary particle size 300 nm): 10 parts by mass Irgacure 184 (BASF Japan shares) (Made by company): 2.0 parts by mass Butyl acetate: 50 parts by mass The above coating solution was applied on a light-transmitting substrate having a front phase difference of 8000 nm using a wire bar, and then dried and placed on a hot plate at 30 ° C. placed. Subsequently, UV irradiation was performed for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd. to form an antireflection layer having a thickness of 5.0 μm.
（帯電防止層：ＡＳ）
　特許第５６７４７２９号公報に記載のイオン伝導性化合物（導電性ポリマー）ＩＰ－１５：５質量部
　Ａ－ＴＭＭＴ（新中村化学工業株式会社）：９２質量部
　１－ブタノール：１０質量部
　メチルエチルケトン：９０質量部
　上記塗布液を、ワイヤーバーを用いて光透過性基材上に塗布後、乾燥させて３０℃のホットプレート上に置いた。次いでフュージョンＵＶシステムズ株式会社製無電極ランプ「Ｄバルブ」（６０ｍＷ／ｃｍ2）にて６秒間ＵＶ照射し、コレステリック液晶相を固定して、厚み５．０μｍの帯電防止層を形成した。 (Antistatic layer: AS)
Ion conductive compound (conductive polymer) IP-15 described in Japanese Patent No. 5674729: IP-15: 5 parts by mass A-TMMT (Shin Nakamura Chemical Co., Ltd.): 92 parts by mass 1-butanol: 10 parts by mass Methyl ethyl ketone: 90 parts by mass Part The coating solution was applied onto a light-transmitting substrate using a wire bar, dried, and placed on a 30 ° C. hot plate. Subsequently, UV irradiation was carried out for 6 seconds with an electrodeless lamp “D bulb” (60 mW / cm 2 ) manufactured by Fusion UV Systems Co., Ltd., and the cholesteric liquid crystal phase was fixed to form an antistatic layer having a thickness of 5.0 μm.
＜実施例１～６、９、１０、比較例１、２、および参考例１～３のハーフミラーの作製＞（シングルインモールド）
　上記円偏光反射板Ｂのコレステリック液晶層の表面にヒートシール剤　Ａ－１００（ＤＩＣ製）をワイヤーバーを用いて塗布後、乾燥させて３．０μｍの熱可塑性溶着層を形成して、転写シートを得た。 <Production of Half Mirrors of Examples 1 to 6, 9, 10, Comparative Examples 1 and 2 and Reference Examples 1 to 3> (Single In Mold)
A heat sealant A-100 (made by DIC) is applied to the surface of the cholesteric liquid crystal layer of the circularly polarizing reflector B using a wire bar, and then dried to form a 3.0 μm thermoplastic weld layer. Got.
　平面板作製用の金型として凹型および凸型の組み合わせからなる金型を用意した。凹型金型上に、転写シートの仮支持体（基材フィルム）が金型の内面に接するような向きで配置し、真空吸引して転写シートを凹部底面に接触させた。この凹型金型に凸型金型を組み合わせて、金型を閉じ、形成された空間にＰＣ（ポリカーボネート、ユーピロンＳ３０００）からなる溶融樹脂を、転写シートの熱可塑性溶着層側の面に接するように、金型内に注入して成形（金型温度９０℃、樹脂温度：３００℃、圧力１００ＭＰａ、時間３０秒）した。室温に冷却し、金型を開いて得られた成形体を取り出した。仮支持体を剥離して、成形体を得た。得られた成形体において、成形樹脂層は１５０ｍｍ×１００ｍｍ×３．０ｍｍの平板であった。 金 A mold comprising a combination of a concave mold and a convex mold was prepared as a mold for producing a flat plate. On the concave mold, the temporary support (base film) of the transfer sheet was arranged so as to contact the inner surface of the mold, and vacuum transfer was performed to bring the transfer sheet into contact with the bottom surface of the concave mold. A convex mold is combined with this concave mold, the mold is closed, and a molten resin made of PC (polycarbonate, Iupilon S3000) is brought into contact with the surface of the transfer sheet on the thermoplastic welding layer side in the formed space. Then, it was poured into a mold and molded (mold temperature 90 ° C., resin temperature: 300 ° C., pressure 100 MPa, time 30 seconds). The molded body obtained by cooling to room temperature and opening the mold was taken out. The temporary support was peeled off to obtain a molded body. In the obtained molded body, the molded resin layer was a flat plate of 150 mm × 100 mm × 3.0 mm.
　このとき成形樹脂層の正面位相差分布は表３に示す値をとるように射出速度、冷却速度を変更して調整した。
　なお、表３、および表４に示す実施例、比較例、および参考例において、成形樹脂層の正面位相差分布は、それぞれ同様に作製した成形樹脂層を９等分した各サンプルの正面位相差をＡｘｏｍｅｔｒｉｃｓ社製のＡｘｏＳｃａｎを用いて測定し、最大値と最小値との差を正面位相差分布として算出した。 At this time, the front phase difference distribution of the molded resin layer was adjusted by changing the injection speed and the cooling speed so as to take the values shown in Table 3.
In the examples, comparative examples, and reference examples shown in Tables 3 and 4, the front phase difference distribution of the molded resin layer is the front phase difference of each sample obtained by equally dividing the molded resin layer produced in the same manner. Was measured using AxoScan manufactured by Axometrics, and the difference between the maximum value and the minimum value was calculated as the front phase difference distribution.
　その後、得られた成形体の成形樹脂層の面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）でパナック社製光学粘着フィルムＰＤＳ１を貼合し、次いで同装置を使用し、光透過性基材（第１の高Ｒｅ位相差膜：表３に示す正面位相差）を貼合して、または貼合しないで、実施例１～６、９、１０、比較例１、２、および参考例１～３のハーフミラーを得た。 Thereafter, an optical adhesive film PDS1 manufactured by Panac was bonded to the surface of the molded resin layer of the obtained molded body with a SEAL type precision single-wafer bonding machine SE550aa (manufactured by Climb Products), and then the same apparatus was used. Examples 1 to 6, 9, 10, Comparative Examples 1 and 2, with or without bonding a permeable substrate (first high Re retardation film: front phase difference shown in Table 3) And the half mirrors of Reference Examples 1 to 3 were obtained.
＜実施例１２～１５のハーフミラーの作製＞
　光透過性基材の代わりにそれぞれ、上記ハードコート層、防眩層、反射防止層、および帯電防止層が設けられた光透過性基材（第１の高Ｒｅ位相差膜：正面位相差８０００ｎｍ）を用いた以外は、実施例１のハーフミラーの作製と同様に、実施例１２～１５のハーフミラーを作製した。なお、粘着フィルムへの貼合は光透過性基材側が粘着フィルムに接触するように行った。 <Production of Half Mirrors of Examples 12 to 15>
Instead of the light transmissive substrate, a light transmissive substrate (first high Re retardation film: front phase difference 8000 nm) provided with the hard coat layer, antiglare layer, antireflection layer, and antistatic layer, respectively. The half mirrors of Examples 12 to 15 were produced in the same manner as the production of the half mirror of Example 1, except that (2) was used. In addition, the bonding to the adhesive film was performed so that the light-transmitting substrate side was in contact with the adhesive film.
＜実施例１１のハーフミラーの作製＞（片面インモールド／片面インサート成形）
　正面位相差８０００ｎｍの光透過性基材（第１の高Ｒｅ位相差膜）の片側にヒートシール剤　Ａ－１００（ＤＩＣ製）をワイヤーバーを用いて塗布後、乾燥させて３．０μｍの熱可塑性溶着層を形成し、熱可塑性溶着層付きの光透過性基材（成形用シート）を得た。
　平面板作製用の金型として凹型および凸型の組み合わせからなる金型を用意した。凸型金型の内面に光透過性基材が接するように、上記熱可塑性溶着層付きの光透過性基材を配置した。凹型金型上に、実施例１で使用した転写シートと同じ転写シートの仮支持体（基材フィルム）が金型の内面に接するような向きで配置し、真空吸引して転写シートを凹部底面に接触させた。両金型を組み合わせて閉じ、ＰＣ（ポリカーボネート、ユーピロンＳ３０００）からなる溶融樹脂を、金型内の光透過性基材と転写シートとの間に注入して成形（金型温度９０℃、樹脂温度：３００℃、圧力１００ＭＰａ、時間３０秒）した。室温に冷却し、金型を開いて得られた成形体を取り出した。仮支持体を剥離して、ハーフミラーを得た。成形樹脂層の正面位相差分布は実施例１と同様に表３に示す値をとるように調整した。 <Production of Half Mirror of Example 11> (Single-sided in-mold / single-sided insert molding)
Heat sealant A-100 (manufactured by DIC) was applied to one side of a light-transmitting substrate (first high Re retardation film) having a front phase difference of 8000 nm using a wire bar, and then dried to heat 3.0 μm. A plastic weld layer was formed to obtain a light-transmitting substrate (molding sheet) with a thermoplastic weld layer.
A mold comprising a combination of a concave mold and a convex mold was prepared as a mold for producing a flat plate. The light transmissive substrate with the thermoplastic weld layer was disposed so that the light transmissive substrate was in contact with the inner surface of the convex mold. On the concave mold, the temporary transfer substrate (base film) of the same transfer sheet as the transfer sheet used in Example 1 is disposed so as to contact the inner surface of the mold, and vacuum transfer is performed to place the transfer sheet on the bottom surface of the concave mold. Contact. Both molds are combined and closed, and a molten resin made of PC (polycarbonate, Iupilon S3000) is injected between the light-transmitting substrate in the mold and the transfer sheet (mold temperature 90 ° C., resin temperature : 300 ° C., pressure 100 MPa, time 30 seconds). The molded body obtained by cooling to room temperature and opening the mold was taken out. The temporary support was peeled off to obtain a half mirror. The front phase difference distribution of the molded resin layer was adjusted to take the values shown in Table 3 as in Example 1.
＜実施例７、８、１６、１７、１８のハーフミラーの作製＞
［成形樹脂層の作製］
　凹型および凸型の組み合わせからなる平面板作製用の金型を閉じ、表３に示す溶融樹脂を注入して成形（金型温度９０℃、樹脂温度：３００℃、圧力１００ＭＰａ、時間３０秒））した。室温に冷却し金型を開いて得られた成形樹脂層（１５０ｍｍ×１００ｍｍ×３ｍｍの平板）を取り出した。
　表３中、溶融樹脂のＰＣはユーピロンＳ３０００、アクリルはスミペックス　ＭＧ５、ＰＥＴはＰＥＴＧ　Ｋ２０１２、ＣＯＰはゼオネックス　Ｅ４８Ｒである。成形樹脂層の正面位相差分布は実施例１と同様に表３に示す値をとるように調整した。 <Production of Half Mirrors of Examples 7, 8, 16, 17, and 18>
[Production of molded resin layer]
Close the mold for producing a flat plate consisting of a combination of concave and convex molds and inject the molten resin shown in Table 3 (mold temperature 90 ° C, resin temperature: 300 ° C, pressure 100 MPa, time 30 seconds)) did. The molded resin layer (flat plate of 150 mm × 100 mm × 3 mm) obtained by cooling to room temperature and opening the mold was taken out.
In Table 3, PC of the molten resin is Iupilon S3000, acrylic is Sumipex MG5, PET is PETG K2012, and COP is ZEONEX E48R. The front phase difference distribution of the molded resin layer was adjusted to take the values shown in Table 3 as in Example 1.
　得られた成形樹脂層の片側の主表面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）を使用してパナック社製光学粘着フィルムＰＤＳ１を貼合した。次いで同装置を使用し粘着フィルムの面に円偏光反射板Ｂまたは直線偏光反射板を貼合した。このとき、円偏光反射板Ｂの場合には、コレステリック液晶層側（仮支持体側と反対側）が粘着フィルムと接触するように貼合し、仮支持体を剥離した。また直線偏光反射板の場合には、任意の面が粘着フィルムと接触するように貼合し、かつ直線偏光反射フィルムの透過軸と画像表示装置の表示側偏光板の透過軸が一致するように貼合した。 An optical adhesive film PDS1 manufactured by Panac was bonded to the main surface on one side of the obtained molded resin layer using a SEAL type precision single wafer bonding machine SE550aa (manufactured by Climb Products). Subsequently, the same apparatus was used, and the circularly polarized light reflector B or the linearly polarized light reflector was bonded to the surface of the adhesive film. At this time, in the case of the circularly polarized light reflector B, the cholesteric liquid crystal layer side (the side opposite to the temporary support side) was bonded so as to contact the adhesive film, and the temporary support was peeled off. In the case of a linearly polarized light reflecting plate, it is bonded so that an arbitrary surface is in contact with the adhesive film, and the transmission axis of the linearly polarized light reflecting film and the transmission axis of the display-side polarizing plate of the image display device are matched. Pasted.
　成形樹脂層の円偏光反射板Ｂあるいは直線偏光反射板と反対側の面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）でパナック社製光学粘着フィルムＰＤＳ１を貼合し、次いで同装置を使用し、光透過性基材（第１の高Ｒｅ位相差膜：正面位相差８０００ｎｍ）を貼合した。 An optical adhesive film PDS1 made by Panac is pasted on the surface of the molded resin layer opposite to the circularly polarized light reflector B or the linearly polarized light reflector with a SEAL type precision single wafer pasting machine SE550aa (Crim Products), and then the same. Using the apparatus, a light-transmitting substrate (first high Re phase difference film: front phase difference 8000 nm) was bonded.
＜比較例３のハーフミラーの作製＞
　実施例７と同様の手順で得た成形樹脂層の片側の主表面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）を使用してパナック社製光学粘着フィルムＰＤＳ１を貼合した。次いで同装置を使用し、光学粘着フィルムと仮支持体付き１／４波長板とを貼合した。このとき、１／４波長板側（仮支持体側と反対側）が粘着フィルムと接触するように貼合し、その後仮支持体を剥離した。
　その後、１／４波長板が設けられた面と反対側の、成形樹脂層の面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）でパナック社製光学粘着フィルムＰＤＳ１を貼合し、次いで同装置を使用し、光透過性基材（第１の高Ｒｅ位相差膜：正面位相差８０００ｎｍ）を貼合した。
　光透過性基材の面に、ＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）を使用し、パナック社製光学粘着フィルムＰＤＳ１を貼合し、次いで同装置を使用し、この粘着フィルムに円偏光反射板Ａを貼合した。このとき、コレステリック液晶層側（仮支持体側と反対側）が粘着フィルムと接触するように貼合し、その後仮支持体を剥離した。 <Production of Half Mirror of Comparative Example 3>
An optical adhesive film PDS1 manufactured by Panac was bonded to the main surface of one side of the molded resin layer obtained in the same procedure as in Example 7 using a SEAL precision sheet-fed bonding machine SE550aa (manufactured by Climb Products). Subsequently, the same apparatus was used, and the optical adhesive film and the quarter wavelength plate with a temporary support were bonded. At this time, it bonded so that the quarter wavelength plate side (opposite side to a temporary support body side) might contact an adhesive film, and the temporary support body was peeled after that.
After that, the optical adhesive film PDS1 made by Panac is pasted on the surface of the molding resin layer opposite to the surface on which the quarter-wave plate is provided, using a SEAL type precision single wafer laminating machine SE550aa (manufactured by Climb Products). Then, using the same apparatus, a light transmissive substrate (first high Re retardation film: front retardation 8000 nm) was bonded.
The SEAL system precision sheet bonding machine SE550aa (manufactured by Climb Products) is used to bond the optical adhesive film PDS1 manufactured by Panac on the surface of the light-transmitting substrate, and then the same apparatus is used. A circularly polarized light reflector A was bonded to the substrate. At this time, it bonded so that the cholesteric liquid crystal layer side (opposite side to a temporary support body side) might contact an adhesive film, and the temporary support body was peeled after that.
＜比較例４のハーフミラーの作製＞
　実施例７と同様の手順で得た成形樹脂層の片側の主表面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）を使用してパナック社製光学粘着フィルムＰＤＳ１を貼合した。次いで同装置を使用し、光学粘着フィルムと光透過性基材（第１の高Ｒｅ位相差膜：正面位相差８０００ｎｍ）とを貼合した。この光透過性基材の面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）でパナック社製光学粘着フィルムＰＤＳ１を貼合し、次いで同装置を使用し、この光学粘着フィルムと仮支持体付き１／４波長板を貼合した。このとき、１／４波長板側（仮支持体側と反対側）が粘着フィルムと接触するように貼合し、その後仮支持体を剥離した。この剥離面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）を使用し、パナック社製光学粘着フィルムＰＤＳ１を貼合し、次いで同装置を使用し、円偏光反射板Ａを貼合した。このとき、コレステリック液晶層側（仮支持体側と反対側）が粘着フィルムと接触するように貼合し、その後仮支持体を剥離した。 <Production of Half Mirror of Comparative Example 4>
An optical adhesive film PDS1 manufactured by Panac was bonded to the main surface of one side of the molded resin layer obtained in the same procedure as in Example 7 using a SEAL precision sheet-fed bonding machine SE550aa (manufactured by Climb Products). Next, using the same apparatus, an optical adhesive film and a light-transmitting substrate (first high Re retardation film: front retardation 8000 nm) were bonded. An optical adhesive film PDS1 manufactured by Panac Co., Ltd. was bonded to the surface of this light-transmitting substrate with a SEAL-type precision single-wafer bonding machine SE550aa (manufactured by Crime Products Co., Ltd.). A quarter-wave plate with a support was bonded. At this time, it bonded so that the quarter wavelength plate side (opposite side to a temporary support body side) might contact an adhesive film, and the temporary support body was peeled after that. SEAL type precision single wafer laminating machine SE550aa (manufactured by Climb Products) is used on this release surface, optical adhesive film PDS1 made by Panac is used, and then the same device is used to apply circularly polarizing reflector A. did. At this time, it bonded so that the cholesteric liquid crystal layer side (opposite side to a temporary support body side) might contact an adhesive film, and the temporary support body was peeled after that.
＜実施例１９、参考例４のハーフミラーの作製＞
　光透過性基材（第２の高Ｒｅ位相差膜：正面位相差４０００ｎｍ）の表面にヒートシール剤　Ａ－１００（ＤＩＣ製）をワイヤーバーを用いて塗布後、乾燥させて３．０μｍの熱可塑性溶着層を形成して、成形用シートを得た。
　平面板作製用の金型として凹型および凸型の組み合わせからなる金型を用意した。凹型金型上に、上記成形用シートの光透過性基材が金型の内面に接するような向きで配置し、真空吸引して成形用シートを凹部底面に接触させた。この凹型金型に凸型金型を組み合わせて、金型を閉じ、形成された空間にＰＣ（ポリカーボネート、ユーピロンＳ３０００）からなる溶融樹脂を、転写シートの熱可塑性溶着層側の面に接するように、金型内に注入して成形（金型温度９０℃、樹脂温度：３００℃、圧力１００ＭＰａ、時間３０秒）した。室温に冷却し、金型を開いて得られた成形体を取り出した。得られた成形体中の成形樹脂層は１５０ｍｍ×１００ｍｍ×３．０ｍｍの平板であった。
　このときの成形樹脂層の正面位相差分布は表に示す値をとるように射出速度、冷却速度を調整して作製した。 <Production of Half Mirror of Example 19 and Reference Example 4>
A heat sealant A-100 (made by DIC) was applied to the surface of a light-transmitting substrate (second high Re retardation film: front retardation 4000 nm) using a wire bar, and then dried to heat 3.0 μm. A plastic welding layer was formed to obtain a molding sheet.
A mold comprising a combination of a concave mold and a convex mold was prepared as a mold for producing a flat plate. On the concave mold, the light-transmitting substrate of the molding sheet was arranged in such a direction as to contact the inner surface of the mold, and vacuum suction was performed to bring the molding sheet into contact with the bottom surface of the concave mold. A convex mold is combined with this concave mold, the mold is closed, and a molten resin made of PC (polycarbonate, Iupilon S3000) is brought into contact with the surface of the transfer sheet on the thermoplastic welding layer side in the formed space. Then, it was poured into a mold and molded (mold temperature 90 ° C., resin temperature: 300 ° C., pressure 100 MPa, time 30 seconds). The molded body obtained by cooling to room temperature and opening the mold was taken out. The molded resin layer in the obtained molded body was a flat plate of 150 mm × 100 mm × 3.0 mm.
The front phase difference distribution of the molded resin layer at this time was prepared by adjusting the injection speed and the cooling speed so as to take the values shown in the table.
　その後、光透過性基材（第２の高Ｒｅ位相差膜）の上からＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）でパナック社製光学粘着フィルムＰＤＳ１を貼合し、次いで同装置を使用し、円偏光反射板Ｂを貼合した。このとき、円偏光反射板Ｂの場合には、コレステリック液晶層側（仮支持体側と反対側）が粘着フィルムと接触するように貼合し、仮支持体を剥離した。
　その後、成形樹脂層の円偏光反射板Ｂと反対側の面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）でパナック社製光学粘着フィルムＰＤＳ１を貼合し、次いで同装置を使用し、光透過性基材（第１の高Ｒｅ位相差膜、正面位相差４０００ｎｍ）を、遅相軸の方向が第２の高Ｒｅ位相差膜の遅相軸の方向と表４に示す角度となるように貼合し、実施例１９、参考例４のハーフミラーを得た。 Thereafter, an optical adhesive film PDS1 made by Panac was pasted on the light-transmitting base material (second high Re retardation film) with a SEAL-type precision single-wafer laminating machine SE550aa (Crim Products), and then the same. Using the apparatus, the circularly polarized light reflector B was bonded. At this time, in the case of the circularly polarized light reflector B, the cholesteric liquid crystal layer side (the side opposite to the temporary support side) was bonded so as to contact the adhesive film, and the temporary support was peeled off.
After that, the optical adhesive film PDS1 made by Panac is pasted on the surface of the molded resin layer opposite to the circularly polarizing reflector B using a SEAL precision single-wafer laminating machine SE550aa (manufactured by Climb Products), and then the same apparatus is used. The direction of the slow axis of the light transmissive substrate (first high Re phase difference film, front phase difference 4000 nm) is the angle shown in Table 4 with respect to the direction of the slow axis of the second high Re phase difference film. The half mirrors of Example 19 and Reference Example 4 were obtained.
＜実施例２０のハーフミラーの作製＞
　実施例７と同様、凹型および凸型の組み合わせからなる平面板作製用の金型を閉じ、表４に示す溶融樹脂を注入して成形（金型温度９０℃、樹脂温度：３００℃、圧力１００ＭＰａ、時間３０秒））した。室温に冷却し金型を開いて得られた成形樹脂層（１５０ｍｍ×１００ｍｍ×３ｍｍの平板）を取り出した。
　表４中、溶融樹脂のＰＣはユーピロンＳ３０００、である。成形樹脂層の正面位相差分布は実施例１と同様に表に示す値をとるように調整した。 <Production of Half Mirror of Example 20>
As in Example 7, the mold for producing a flat plate comprising a combination of a concave mold and a convex mold was closed, and the molten resin shown in Table 4 was injected and molded (mold temperature 90 ° C., resin temperature: 300 ° C., pressure 100 MPa. , Time 30 seconds)). The molded resin layer (flat plate of 150 mm × 100 mm × 3 mm) obtained by cooling to room temperature and opening the mold was taken out.
In Table 4, the molten resin PC is Iupilon S3000. The front phase difference distribution of the molded resin layer was adjusted to take the values shown in the table in the same manner as in Example 1.
　得られた成形樹脂層の片側の主表面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）を使用してパナック社製光学粘着フィルムＰＤＳ１を貼合した。次いで同装置を使用し粘着フィルムの面に光透過性基材（第２の高Ｒｅ位相差膜、正面位相差４０００ｎｍ）を貼合し、その上からＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）でパナック社製光学粘着フィルムＰＤＳ１を貼合し、次いで同装置を使用し、円偏光反射板Ｂを貼合した。このとき、円偏光反射板Ｂの場合には、コレステリック液晶層側（仮支持体側と反対側）が粘着フィルムと接触するように貼合し、仮支持体を剥離した。 An optical adhesive film PDS1 manufactured by Panac was bonded to the main surface on one side of the obtained molded resin layer using a SEAL type precision single wafer bonding machine SE550aa (manufactured by Climb Products). Next, using the same device, a light-transmitting substrate (second high Re retardation film, front retardation 4000 nm) is bonded to the surface of the adhesive film, and SEAL type precision single wafer bonding machine SE550aa (Climb) An optical adhesive film PDS1 manufactured by Panac Co., Ltd. was pasted with a product manufactured by Products Co., Ltd., and then the circularly polarizing reflector B was pasted using the same apparatus. At this time, in the case of the circularly polarized light reflector B, the cholesteric liquid crystal layer side (the side opposite to the temporary support side) was bonded so as to contact the adhesive film, and the temporary support was peeled off.
　成形樹脂層の円偏光反射板Ｂと反対側の面にＳＥＡＬ方式精密枚葉貼合機ＳＥ５５０ａａ（クライムプロダクツ社製）でパナック社製光学粘着フィルムＰＤＳ１を貼合し、次いで同装置を使用し、光透過性基材（第１の高Ｒｅ位相差膜、正面位相差４０００ｎｍ）を、遅相軸の方向が第２の高Ｒｅ位相差膜の遅相軸の方向と０°の角度をなすように貼合し、実施例２０のハーフミラーを得た。 An optical adhesive film PDS1 manufactured by Panac was bonded to the surface of the molded resin layer opposite to the circularly polarizing reflector B using a SEAL type precision single wafer bonding machine SE550aa (manufactured by Climb Products), and then the same apparatus was used. The light transmissive substrate (first high Re phase difference film, front phase difference 4000 nm) is set so that the slow axis direction forms an angle of 0 ° with the slow axis direction of the second high Re phase difference film. The half mirror of Example 20 was obtained.
＜ハーフミラーの評価＞
［画像の色ムラの評価］
　以下の画像表示装置の画像表示面に画像表示面と平行になるようにハーフミラーを配置して、白画像を表示させた。
（画像表示装置）
液晶モニター白色ＬＥＤタイプ：（ＦＬＡＴＯＲＯＮ　Ｅ２２６０Ｖ（ＬＧ　Ｅｌｅｃｔｒｏｎｉｃｓ　Ｊａｐａｎ社製））
蛍光灯タイプ：（ＦＬＡＴＯＲＯＮ　Ｗ２２４０Ｖ（ＬＧ　Ｅｌｅｃｔｒｏｎｉｃｓ　Ｊａｐａｎ社製）） <Evaluation of half mirror>
[Evaluation of uneven color of image]
A half mirror was arranged on the image display surface of the following image display device so as to be parallel to the image display surface, and a white image was displayed.
(Image display device)
LCD monitor white LED type: (FLATORON E2260V (manufactured by LG Electronics Japan))
Fluorescent lamp type: (FLATORON W2240V (manufactured by LG Electronics Japan))
　上記の平行状態を維持したまま光透過性基材の遅相軸と画像表示装置の視認側偏光子の偏光軸とが形成する角を０°～９０°の間で表３、表４に示すように位置を設定した。画像表示装置において白画像を表示したときの画像を観察面から偏光サングラスを着けて観察し、色ムラ発生の有無及び程度を確認した。下記の基準に従って評価した。結果を表３、表４に示す。
　無：　正面から観察したときに、色ムラが発生せず視認性に問題ない。
　有り：　正面から観察したときに、色ムラが観察される。 Tables 3 and 4 show the angles formed by the slow axis of the light-transmitting substrate and the polarization axis of the viewing-side polarizer of the image display device between 0 ° and 90 ° while maintaining the above parallel state. The position was set as follows. When the white image was displayed on the image display device, the image was observed from the observation surface with polarized sunglasses, and the presence and extent of color unevenness was confirmed. Evaluation was made according to the following criteria. The results are shown in Tables 3 and 4.
None: When observed from the front, color unevenness does not occur and visibility is not a problem.
Existence: Color unevenness is observed when observed from the front.
［ミラー反射像のムラの評価］
　光透過性基材の遅相軸と画像表示装置の視認側偏光子の偏光軸とが形成する角を、画像の色ムラの評価と同様に、０°～９０°の間で表３に示すように位置を設定した。画像表示装置をオフとした時のミラー反射像を、観察面から偏光サングラスを着けて観察し、色ムラ発生の有無及び程度を確認した。下記の基準に従って評価した。結果を表３、表４に示す。
　無：　正面から観察したときに、色ムラが発生せず視認性に問題ない。
　有り：　正面から観察したときに、色ムラが観察される。 [Evaluation of unevenness of mirror reflection image]
Table 3 shows the angles formed by the slow axis of the light-transmitting substrate and the polarization axis of the viewing-side polarizer of the image display device in the range of 0 ° to 90 °, as in the case of the color unevenness evaluation of the image. The position was set as follows. The mirror reflection image when the image display device was turned off was observed from the observation surface with polarized sunglasses, and the presence and extent of color unevenness was confirmed. Evaluation was made according to the following criteria. The results are shown in Tables 3 and 4.
None: When observed from the front, color unevenness does not occur and visibility is not a problem.
Existence: Color unevenness is observed when observed from the front.
［直線偏光透過率］
　直線偏光透過率を日本分光社製の紫外可視近赤外分光光度計Ｖ－６７０を用いて測定した。直線偏光に対する透過率の測定は、直線偏光板を分光光度計の光源側において、その偏光透過軸と１／４波長板の遅相軸が４５°になるように配置して測定を行った。このようにして得られた自然光透過率の波長４００ｎｍから７００ｎｍまでの直線偏光に対する平均透過率を算出し、８０％以上を良、８０％未満を不良とした。結果を表３、表４に示す。 [Linear polarization transmittance]
The linearly polarized light transmittance was measured using an ultraviolet-visible near-infrared spectrophotometer V-670 manufactured by JASCO Corporation. The transmittance for linearly polarized light was measured by placing a linearly polarizing plate on the light source side of the spectrophotometer so that the polarization transmission axis and the slow axis of the quarter wavelength plate were 45 °. The average transmittance with respect to the linearly polarized light having a wavelength of 400 nm to 700 nm of the natural light transmittance thus obtained was calculated, and 80% or more was judged good and less than 80% was judged as bad. The results are shown in Tables 3 and 4.
Figure JPOXMLDOC01-appb-T000004
Figure JPOXMLDOC01-appb-T000004
Figure JPOXMLDOC01-appb-T000005
Figure JPOXMLDOC01-appb-T000005

Claims (19)

  1. 観察面、成形樹脂層、および偏光反射板をこの順で含み、
    前記観察面と前記偏光反射板との間に高Ｒｅ位相差膜を少なくとも１つ含み、前記高Ｒｅ位相差膜の正面位相差の合計が３０００ｎｍ以上であり、
    前記高Ｒｅ位相差膜として第１の高Ｒｅ位相差膜を、前記観察面と前記成形樹脂層との間に、含むハーフミラー。     Including the observation surface, the molded resin layer, and the polarizing reflector in this order,
    Including at least one high Re retardation film between the observation surface and the polarizing reflector, the total of the front retardation of the high Re retardation film is 3000 nm or more,
    A half mirror comprising a first high Re retardation film as the high Re retardation film between the observation surface and the molding resin layer.
  2. 前記成形樹脂層の正面位相差分布が１００ｎｍ以上である請求項１に記載のハーフミラー。 The half mirror according to claim 1, wherein a front phase difference distribution of the molded resin layer is 100 nm or more.
  3. 前記高Ｒｅ位相差膜の正面位相差の合計が５０００ｎｍ以上である請求項１または２に記載のハーフミラー。 The half mirror according to claim 1 or 2, wherein a total of the front phase differences of the high Re retardation film is 5000 nm or more.
  4. 前記第１の高Ｒｅ位相差膜の正面位相差が３０００ｎｍ以上である請求項１～３のいずれか一項に記載のハーフミラー。 The half mirror according to any one of claims 1 to 3, wherein a front phase difference of the first high Re retardation film is 3000 nm or more.
  5. 前記高Ｒｅ位相差膜として前記第１の高Ｒｅ位相差膜のみを含む請求項１～４のいずれか一項に記載のハーフミラー。 The half mirror according to any one of claims 1 to 4, wherein only the first high Re retardation film is included as the high Re retardation film.
  6. 前記高Ｒｅ位相差膜として第２の高Ｒｅ位相差膜を、前記成形樹脂層と前記偏光反射板との間に、さらに含む請求項１～４のいずれか一項に記載のハーフミラー。 The half mirror according to any one of claims 1 to 4, further comprising a second high Re retardation film as the high Re retardation film between the molding resin layer and the polarizing reflector.
  7. 前記第１の高Ｒｅ位相差膜の遅相軸の方向と、前記第２の高Ｒｅ位相差膜の遅相軸の方向と、が同じである請求項６に記載のハーフミラー。 The half mirror according to claim 6, wherein a direction of a slow axis of the first high Re retardation film and a direction of a slow axis of the second high Re retardation film are the same.
  8. 前記第２の高Ｒｅ位相差膜と前記成形樹脂層との間に接着層または熱可塑性溶着層を含む請求項６または７に記載のハーフミラー。 The half mirror according to claim 6 or 7, comprising an adhesive layer or a thermoplastic welding layer between the second high Re retardation film and the molding resin layer.
  9. 前記成形樹脂層が、ポリカーボネート、ポリ（メタ）アクリレート、ポリエステル、およびシクロオレフィンポリマーからなる群より選択されるいずれか1つ以上のポリマーを含む請求項１～８のいずれか一項に記載のハーフミラー。 The half according to any one of claims 1 to 8, wherein the molded resin layer contains one or more polymers selected from the group consisting of polycarbonate, poly (meth) acrylate, polyester, and cycloolefin polymer. mirror.
  10. 前記偏光反射板が円偏光反射層である請求項１～９のいずれか一項に記載のハーフミラー。 The half mirror according to any one of claims 1 to 9, wherein the polarizing reflector is a circularly polarizing reflector layer.
  11. 前記円偏光反射層がコレステリック液晶層を含む請求項１０に記載のハーフミラー。 The half mirror according to claim 10, wherein the circularly polarized light reflection layer includes a cholesteric liquid crystal layer.
  12. 前記円偏光反射層が３層以上のコレステリック液晶層を含む請求項１１に記載のハーフミラー。 The half mirror according to claim 11, wherein the circularly polarized light reflection layer includes three or more cholesteric liquid crystal layers.
  13. １／４波長板をさらに含み、
    前記成形樹脂層、前記偏光反射板、および前記１／４波長板をこの順に含む請求項１０～１２のいずれか一項に記載のハーフミラー。     A quarter wave plate;
    The half mirror according to any one of claims 10 to 12, including the molded resin layer, the polarizing reflector, and the quarter-wave plate in this order.
  14. 前記偏光反射板と前記１／４波長板とが互いに直接接している請求項１３に記載のハーフミラー。 The half mirror according to claim 13, wherein the polarizing reflection plate and the quarter-wave plate are in direct contact with each other.
  15. 前記成形樹脂層と前記偏光反射板との間に接着層または熱可塑性溶着層を含む請求項１～１４のいずれか一項に記載のハーフミラー。 The half mirror according to any one of claims 1 to 14, further comprising an adhesive layer or a thermoplastic weld layer between the molded resin layer and the polarizing reflector.
  16. 前記第１の高Ｒｅ位相差膜と前記成形樹脂層との間に接着層または熱可塑性溶着層を含む請求項１～１５のいずれか一項に記載のハーフミラー。 The half mirror according to any one of claims 1 to 15, further comprising an adhesive layer or a thermoplastic welding layer between the first high Re retardation film and the molding resin layer.
  17. 請求項１～１６のいずれか一項に記載のハーフミラー、および画像表示装置を含み、
    前記観察面、前記成形樹脂層、前記偏光反射板、および前記画像表示装置がこの順で配置されている画像表示機能付きミラー。     A half mirror according to any one of claims 1 to 16, and an image display device,
    The mirror with an image display function in which the observation surface, the molding resin layer, the polarizing reflector, and the image display device are arranged in this order.
  18. 前記画像表示装置は直線偏光を出射して画像を形成し、
    前記画像表示装置が、連続的な発光スペクトルを与えるバックライトを有し、
    前記第１の高Ｒｅ位相差膜の遅相軸が前記直線偏光の偏光方向と３０°～６０°の角度をなしている請求項１７に記載の画像表示機能付きミラー。     The image display device emits linearly polarized light to form an image,
    The image display device has a backlight that gives a continuous emission spectrum;
    The mirror with an image display function according to claim 17, wherein a slow axis of the first high Re retardation film forms an angle of 30 ° to 60 ° with a polarization direction of the linearly polarized light.
  19. 前記画像表示装置が液晶表示装置であり、前記バックライトが白色ＬＥＤである請求項１８に記載の画像表示機能付きミラー。 The mirror with an image display function according to claim 18, wherein the image display device is a liquid crystal display device, and the backlight is a white LED.
PCT/JP2017/021699 2016-06-21 2017-06-12 Half mirror and mirror with image displaying function WO2017221760A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US16/178,939 US20190079304A1 (en) 2016-06-21 2018-11-02 Half mirror and mirror with image display function

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2016122675 2016-06-21
JP2016-122675 2016-06-21
JP2017-108085 2017-05-31
JP2017108085A JP2017227879A (en) 2016-06-21 2017-05-31 Half mirror and mirror having image display function

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US16/178,939 Continuation US20190079304A1 (en) 2016-06-21 2018-11-02 Half mirror and mirror with image display function

Publications (1)

Publication Number Publication Date
WO2017221760A1 true WO2017221760A1 (en) 2017-12-28

Family

ID=60783476

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2017/021699 WO2017221760A1 (en) 2016-06-21 2017-06-12 Half mirror and mirror with image displaying function

Country Status (1)

Country Link
WO (1) WO2017221760A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020166155A (en) * 2019-03-29 2020-10-08 東洋紡株式会社 Method of manufacturing liquid crystal compound layer laminate, and method for inspecting liquid crystal compound layer
CN111936925A (en) * 2018-03-29 2020-11-13 松下知识产权经营株式会社 Display device
WO2020262474A1 (en) * 2019-06-27 2020-12-30 富士フイルム株式会社 Decorative film for molding, molded article, and display

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005321544A (en) * 2004-05-07 2005-11-17 Nikon Corp Projection type display device
JP2015141318A (en) * 2014-01-29 2015-08-03 富士フイルム株式会社 projection system and projector
WO2016088708A1 (en) * 2014-12-01 2016-06-09 富士フイルム株式会社 Mirror having image display function

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005321544A (en) * 2004-05-07 2005-11-17 Nikon Corp Projection type display device
JP2015141318A (en) * 2014-01-29 2015-08-03 富士フイルム株式会社 projection system and projector
WO2016088708A1 (en) * 2014-12-01 2016-06-09 富士フイルム株式会社 Mirror having image display function

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111936925A (en) * 2018-03-29 2020-11-13 松下知识产权经营株式会社 Display device
JP2020166155A (en) * 2019-03-29 2020-10-08 東洋紡株式会社 Method of manufacturing liquid crystal compound layer laminate, and method for inspecting liquid crystal compound layer
JP7392278B2 (en) 2019-03-29 2023-12-06 東洋紡株式会社 Method for manufacturing liquid crystal compound laminate and method for inspecting liquid crystal compound layer
WO2020262474A1 (en) * 2019-06-27 2020-12-30 富士フイルム株式会社 Decorative film for molding, molded article, and display
JPWO2020262474A1 (en) * 2019-06-27 2020-12-30
JP7317113B2 (en) 2019-06-27 2023-07-28 富士フイルム株式会社 Decorative films for molding, moldings, and displays

Similar Documents

Publication Publication Date Title
US10501017B2 (en) Vehicle mirror with image display function
JP2017227879A (en) Half mirror and mirror having image display function
US11142128B2 (en) Anti-glare mirror with image display function
WO2017145580A1 (en) Vehicle mirror including image display function and method for manufacturing same
US10800333B2 (en) Vehicle mirror with image display function and method of manufacturing the same
WO2017221760A1 (en) Half mirror and mirror with image displaying function
US10670781B2 (en) Mirror with image display function and half mirror
JP2017122776A (en) Mirror with image display function and half mirror
CN108474900B (en) Semitransparent mirror and mirror with image display function
JP6632479B2 (en) Half mirror and mirror with image display function
US10569713B2 (en) Vehicle mirror with image display function
WO2018146958A1 (en) Half mirror, method for producing half mirror, and mirror provided with image display function
JP2017227720A (en) Resin mirror, mirror having image display function, method for manufacturing resin mirror, and transfer sheet
JP6514232B2 (en) Mirror with image display function for vehicles
JP6793781B2 (en) Mirror with image display function for vehicles
JP6806848B2 (en) Mirror with image display function for vehicles
JP7335863B2 (en) Mirror with image display function for vehicles
WO2017208559A1 (en) Half mirror, and mirror with image display function
WO2017183428A1 (en) Mirror with image display function and half mirror

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17815229

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17815229

Country of ref document: EP

Kind code of ref document: A1