WO2016031744A1 - 液晶表示装置 - Google Patents
液晶表示装置 Download PDFInfo
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- WO2016031744A1 WO2016031744A1 PCT/JP2015/073646 JP2015073646W WO2016031744A1 WO 2016031744 A1 WO2016031744 A1 WO 2016031744A1 JP 2015073646 W JP2015073646 W JP 2015073646W WO 2016031744 A1 WO2016031744 A1 WO 2016031744A1
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- liquid crystal
- display device
- alignment film
- crystal display
- formula
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- 0 CC(C)(CC(*)CC1(C)C)N1O* Chemical compound CC(C)(CC(*)CC1(C)C)N1O* 0.000 description 3
- BBOZNQARJOMDMQ-UHFFFAOYSA-N CC(C)(CC(CC(CCCCCCCCC(OC(CC1(C)C)CC(C)(C)N1O)=O)=O)CC1(C)C)N1O Chemical compound CC(C)(CC(CC(CCCCCCCCC(OC(CC1(C)C)CC(C)(C)N1O)=O)=O)CC1(C)C)N1O BBOZNQARJOMDMQ-UHFFFAOYSA-N 0.000 description 1
- ZXDIQRGIYADNBI-UHFFFAOYSA-N CC(C)(CC(CC1(C)C)OC(CCC(OC(CC2(C)C)CC(C)(C)N2O)=O)=O)N1O Chemical compound CC(C)(CC(CC1(C)C)OC(CCC(OC(CC2(C)C)CC(C)(C)N2O)=O)=O)N1O ZXDIQRGIYADNBI-UHFFFAOYSA-N 0.000 description 1
- LKJXECVSGJBZGK-UHFFFAOYSA-N CC(C)(CC(CC1(C)C)OCCCCOC(CC2(C)C)CC(C)(C)N2O)N1O Chemical compound CC(C)(CC(CC1(C)C)OCCCCOC(CC2(C)C)CC(C)(C)N2O)N1O LKJXECVSGJBZGK-UHFFFAOYSA-N 0.000 description 1
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- 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
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- C08F32/00—Homopolymers and copolymers of cyclic compounds having no unsaturated aliphatic radicals in a side chain, and having one or more carbon-to-carbon double bonds in a carbocyclic ring system
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- C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
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- C09K19/06—Non-steroidal liquid crystal compounds
- C09K19/08—Non-steroidal liquid crystal compounds containing at least two non-condensed rings
- C09K19/30—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing saturated or unsaturated non-aromatic rings, e.g. cyclohexane rings
- C09K19/3098—Unsaturated non-aromatic rings, e.g. cyclohexene rings
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- C09K19/52—Liquid crystal materials characterised by components which are not liquid crystals, e.g. additives with special physical aspect: solvents, solid particles
- C09K19/54—Additives having no specific mesophase characterised by their chemical composition
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- 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
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- 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
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- G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
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- G—PHYSICS
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- 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
- G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
- G02F1/13378—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers by treatment of the surface, e.g. embossing, rubbing or light irradiation
- G02F1/133788—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers by treatment of the surface, e.g. embossing, rubbing or light irradiation by light irradiation, e.g. linearly polarised light photo-polymerisation
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- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F222/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a carboxyl radical and containing at least one other carboxyl radical in the molecule; Salts, anhydrides, esters, amides, imides, or nitriles thereof
- C08F222/10—Esters
- C08F222/1006—Esters of polyhydric alcohols or polyhydric phenols
- C08F222/102—Esters of polyhydric alcohols or polyhydric phenols of dialcohols, e.g. ethylene glycol di(meth)acrylate or 1,4-butanediol dimethacrylate
- C08F222/1025—Esters of polyhydric alcohols or polyhydric phenols of dialcohols, e.g. ethylene glycol di(meth)acrylate or 1,4-butanediol dimethacrylate of aromatic dialcohols
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- C09K19/00—Liquid crystal materials
- C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
- C09K2019/0444—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit characterized by a linking chain between rings or ring systems, a bridging chain between extensive mesogenic moieties or an end chain group
- C09K2019/0448—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit characterized by a linking chain between rings or ring systems, a bridging chain between extensive mesogenic moieties or an end chain group the end chain group being a polymerizable end group, e.g. -Sp-P or acrylate
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- C09K19/00—Liquid crystal materials
- C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
- C09K19/06—Non-steroidal liquid crystal compounds
- C09K19/08—Non-steroidal liquid crystal compounds containing at least two non-condensed rings
- C09K19/10—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings
- C09K19/12—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings at least two benzene rings directly linked, e.g. biphenyls
- C09K2019/121—Compounds containing phenylene-1,4-diyl (-Ph-)
- C09K2019/122—Ph-Ph
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- C09K19/00—Liquid crystal materials
- C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
- C09K19/06—Non-steroidal liquid crystal compounds
- C09K19/08—Non-steroidal liquid crystal compounds containing at least two non-condensed rings
- C09K19/30—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing saturated or unsaturated non-aromatic rings, e.g. cyclohexane rings
- C09K19/3001—Cyclohexane rings
- C09K19/3003—Compounds containing at least two rings in which the different rings are directly linked (covalent bond)
- C09K2019/3009—Cy-Ph
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- C09K19/00—Liquid crystal materials
- C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
- C09K19/06—Non-steroidal liquid crystal compounds
- C09K19/08—Non-steroidal liquid crystal compounds containing at least two non-condensed rings
- C09K19/30—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing saturated or unsaturated non-aromatic rings, e.g. cyclohexane rings
- C09K19/3001—Cyclohexane rings
- C09K19/3003—Compounds containing at least two rings in which the different rings are directly linked (covalent bond)
- C09K2019/3016—Cy-Ph-Ph
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- 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
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- 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
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- G02F1/133528—Polarisers
- G02F1/133545—Dielectric stack polarisers
Definitions
- the present invention relates to a liquid crystal display device. More specifically, the present invention relates to a liquid crystal display device in which the alignment of liquid crystal molecules is controlled by an alignment film.
- a liquid crystal display device is a display device that uses a liquid crystal composition for display.
- a typical display method is to irradiate light from a backlight onto a liquid crystal panel in which the liquid crystal composition is sealed between a pair of substrates. The amount of light transmitted through the liquid crystal panel is controlled by applying a voltage to the liquid crystal composition to change the orientation of the liquid crystal molecules.
- Such a liquid crystal display device has features such as thinness, light weight, and low power consumption, and thus is used in electronic devices such as smartphones, tablet PCs, and car navigation systems. In recent years, in applications such as smartphones, higher definition of pixels has progressed, and accordingly, the number and area of wirings and black matrices provided in a liquid crystal panel have tended to increase.
- the alignment of liquid crystal molecules in a state where no voltage is applied is generally controlled by an alignment film that has been subjected to an alignment treatment.
- a rubbing method of rubbing the alignment film surface with a roller or the like has been widely used.
- a step is likely to occur on the substrate surface in the liquid crystal panel. If there is a step on the substrate surface, the vicinity of the step may not be properly rubbed by the rubbing method. If the alignment treatment is not uniform, the contrast ratio is lowered in the liquid crystal display device.
- the alignment process can be performed without contacting the surface of the alignment film, so even if there are steps on the substrate surface, the alignment process is less likely to be uneven, and good liquid crystal alignment is achieved over the entire surface of the substrate. There is an advantage that you can.
- an increase in the number and area of wirings and black matrices provided in the liquid crystal panel also reduces the area ratio (opening ratio) of the openings that can be used for display.
- a decrease in the aperture ratio directly leads to a decrease in the amount of light that can be transmitted through the liquid crystal panel. Therefore, in order to maintain the display performance of the liquid crystal display device such as the contrast ratio, it is considered that the brightness of the backlight is greatly improved. Has been.
- Patent Document 1 discloses that an antioxidant and a light stabilizer are added to the liquid crystal composition.
- Patent Document 2 also discloses adding a stabilizer to the liquid crystal composition (see Table C in paragraphs [0208] to [0211]).
- Radiation-generating liquid crystal panel is irradiated with backlight light (amount of energy: h ⁇ ), and photofunctional groups contained in the photo-alignment film are excited as shown in the following formula (AI).
- a radical is generated by the cleavage of the photofunctional group.
- a backlight with high brightness is used, radical generation becomes significant.
- liquid crystal compositions are added with additives such as antioxidants and light stabilizers.
- additives such as antioxidants and light stabilizers.
- these additives are specific to the case where a photo-alignment film is used. It was not intended to solve the problem.
- an antioxidant or the like having a function of desorbing oxygen from an oxide generated under the influence of light or heat in the presence of oxygen has been added to the liquid crystal composition.
- the present invention has been made in view of the above situation, and provides a liquid crystal display device that maintains a good voltage holding ratio over a long period of time by using a photo-alignment film and prevents the occurrence of burn-in and spots on a display screen. It is for the purpose.
- the inventors have reduced the voltage holding ratio at the edge of the screen of the liquid crystal panel and the edge of the box pattern display, and thereby burn-in on the display screen.
- the present inventors have found for the first time that the cause of the failure is that radicals are generated in the photo-alignment film by being exposed to the light of the backlight, and this is eluted in the liquid crystal layer. It was.
- it was conceived that the above problem could be solved brilliantly by including a radical scavenger in the liquid crystal layer, and the present invention was achieved.
- one embodiment of the present invention includes an active matrix liquid crystal panel and a backlight
- the liquid crystal panel includes a liquid crystal layer, a pair of substrates that sandwich the liquid crystal layer, and the liquid crystal layer side of the pair of substrates.
- the alignment film is a photo-alignment film formed from a material having photo-alignment properties
- the liquid crystal layer contains a liquid crystal material and a radical scavenger. It may be a liquid crystal display device.
- the liquid crystal display device of the present invention since it has the above-described configuration, radicals eluted in the liquid crystal layer can be deactivated by the radical scavenger, and a decrease in voltage holding ratio can be prevented. Thereby, a favorable voltage holding ratio can be maintained over a long period of time using the photo-alignment film, and the occurrence of image sticking and spots on the display screen can be prevented.
- FIG. 1 is a cross-sectional view schematically showing the liquid crystal display device of the present embodiment.
- the liquid crystal display device of this embodiment includes an active matrix liquid crystal panel 20 and a backlight 10, and the liquid crystal panel 20 includes a liquid crystal layer 23, a pair of substrates 21 that sandwich the liquid crystal layer 23, and the pair of pairs. And an alignment film 22 disposed on the surface of the substrate 21 on the liquid crystal layer 23 side.
- the alignment film 22 is a photo-alignment film formed of a material having photo-alignment properties. A liquid crystal material and a radical scavenger.
- the active matrix liquid crystal panel 20 includes a liquid crystal layer 23, a pair of substrates 21 that sandwich the liquid crystal layer 23, and an alignment film 22 that is disposed on the surface of the pair of substrates 21 on the liquid crystal layer 23 side.
- Any ordinary liquid crystal panel that employs an active matrix display method may be used.
- the active matrix display method normally, when an active element such as a thin film transistor (TFT) provided in each pixel is on, a signal voltage is applied to the electrode through the TFT, and the charge charged in the pixel at this time is , Hold while the active element is off.
- a voltage holding ratio (VHR) indicates a ratio of holding the charged charge during one frame period (for example, 16.7 ms). That is, a low VHR means that the voltage applied to the liquid crystal layer tends to decay with time. In the active matrix display method, it is required to increase the VHR.
- Examples of the pair of substrates 21 include a combination of an active matrix substrate (TFT substrate) and a color filter (CF) substrate.
- TFT substrate active matrix substrate
- CF color filter
- the active matrix substrate those normally used in the field of liquid crystal display devices can be used.
- the configuration is such that a plurality of parallel gate signal lines on a transparent substrate; a plurality of sources extending in a direction perpendicular to the gate signal lines and parallel to each other Signal lines; active elements such as TFTs arranged corresponding to the intersections of gate signal lines and source signal lines; pixel electrodes arranged in a matrix in a region partitioned by gate signal lines and source signal lines
- TFT substrate active matrix substrate
- CF color filter
- a common wiring; a counter electrode connected to the common wiring, and the like are further provided.
- a TFT having a channel formed of IGZO (indium-gallium-zinc-oxygen) which is an oxide semiconductor is preferably used.
- the color filter substrate those usually used in the field of liquid crystal display devices can be used.
- the configuration of the color filter substrate include a configuration in which a black matrix formed in a lattice shape, a color filter formed inside a lattice, that is, a pixel, and the like are provided on a transparent substrate.
- the pair of substrates 21 may be one in which both the color filter and the active matrix are formed on one substrate.
- An alignment film 22 is interposed between the pair of substrates 21 and the liquid crystal layer 23.
- the alignment film 22 has a function of controlling the alignment of the liquid crystal molecules in the liquid crystal layer 23.
- the alignment film 22 mainly functions.
- the alignment of the liquid crystal molecules in the liquid crystal layer 23 is controlled.
- an angle formed by the major axis of the liquid crystal molecules with respect to the surfaces of the pair of substrates 21 is called a “pretilt angle”.
- the “pretilt angle” means an angle of inclination of liquid crystal molecules from a direction parallel to the substrate surface, the angle parallel to the substrate surface is 0 °, and the normal angle of the substrate surface is 90 °. It is.
- the size of the pretilt angle of the liquid crystal molecules provided by the alignment film 22 is not particularly limited, and the alignment film 22 may be a horizontal alignment film or a vertical alignment film, but preferably a horizontal alignment. It is a membrane.
- the pretilt angle is preferably substantially 0 ° (for example, less than 10 °), and is 0 ° from the viewpoint of obtaining an effect of maintaining good contrast characteristics over a long period of time. More preferred.
- the pretilt angle is preferably 0 ° from the viewpoint of viewing angle characteristics, but when the display mode is the TN mode, Due to restrictions, the pretilt angle is set to about 2 °, for example.
- the alignment film 22 is a photo-alignment film formed from a material exhibiting photo-alignment properties.
- a material exhibiting photo-alignment property has a property (alignment regulating force) that causes structural changes when irradiated with light (electromagnetic waves) such as ultraviolet light and visible light, and regulates the orientation of liquid crystal molecules present in the vicinity thereof. It means all the materials that develop and the materials whose orientation regulating force changes in size and / or direction.
- Examples of the material exhibiting photo-alignment include those containing a photoreactive site in which a reaction such as dimerization (dimer formation), isomerization, photofleece transition, or decomposition occurs due to light irradiation.
- Examples of photoreactive sites (functional groups) that are dimerized and isomerized by light irradiation include, for example, cinnamate represented by the following formula (B-1), 4-chalcone represented by the following formula (B-2-1), 4′-chalcone represented by the formula (B-2-2), coumarin represented by the following formula (B-3), and stilbene represented by the following formula (B-4) are preferably used.
- the following formula (B-1-I) shows the isomerization reaction and dimerization reaction of cinnamate.
- azobenzene is used suitably, for example.
- the trans form of azobenzene is shown in the following formula (B-5-1), and the cis isomer of azobenzene is shown in the following formula (B-5-2).
- a phenol ester structure represented by the following formula (B-6) is preferably used as a photoreactive site that undergoes photofleece transition upon irradiation with light.
- the phenol ester structure undergoes optical fleece transition as shown in the following formula (B-6-I).
- a cyclobutane structure is preferably used as the photoreactive site that is decomposed by light irradiation.
- a photo-alignment film containing a cyclobutane structure for example, an acid anhydride having a cyclobutane structure represented by the following formula (B-7-1) and an amine compound represented by the following formula (B-7-2) are used as monomers. Examples thereof include polymers obtained by copolymerization.
- the cyclobutane structure is ring-opened and exhibits photo-alignment.
- the hydrogen atom in the cyclobutane structure represented by the following formula (B-7-1) may be substituted with another atom or a functional group.
- a polymer supported alignment (PSA) technique may be used.
- PSA polymer supported alignment
- a liquid crystal composition containing a photopolymerizable monomer is sealed between a pair of substrates 21, and then the liquid crystal layer 23 is irradiated with light to polymerize the photopolymerizable monomer, whereby the surface of the alignment film 22 is obtained.
- a polymer (polymer) is formed on the substrate, and the initial tilt (pretilt) of the liquid crystal is fixed by this polymer.
- the PSA technology for example, a form having a layer containing a polymer obtained by polymerizing a photopolymerizable monomer represented by the following formula (C) on the surface of the alignment film 22 on the liquid crystal layer 23 side Is mentioned.
- A1-Y-A2 (C) (In the formula, Y represents a structure containing at least one benzene ring and / or a condensed benzene ring, and a hydrogen atom in the benzene ring and the condensed benzene ring may be replaced by a halogen atom, and A1 and A2 At least one represents acrylate or methacrylate, and A1 and A2 are directly bonded to the benzene ring or the condensed benzene ring.
- the skeleton Y in the above formula (C) preferably has a structure represented by the following formula (C-1), (C-2) or (C-3). Note that hydrogen atoms in the following formulas (C-1), (C-2), and (C-3) may be independently replaced with halogen atoms.
- photopolymerizable monomer represented by the above formula (C) include the following formulas (C-1-1), (C-1-2), and (C-3-1).
- the liquid crystal layer 23 contains a liquid crystal material and a radical scavenger.
- the liquid crystal material may have a negative dielectric anisotropy ( ⁇ ) defined by the following formula (P), or a positive value. That is, the liquid crystal material may have a negative dielectric anisotropy or a positive dielectric anisotropy.
- ⁇ (dielectric constant in the major axis direction) ⁇ (dielectric constant in the minor axis direction) (P)
- the use of a liquid crystal material having a negative dielectric anisotropy is greater than the use of a liquid crystal material having a positive dielectric anisotropy.
- the burn-in and stain defects tended to appear more obvious. This is presumably because the liquid crystal material having negative dielectric anisotropy has a large polarization in the minor axis direction, and thus the influence of the decrease in VHR when ionized becomes large. That is, the radical scavenger used in the present invention exhibits a great effect in a system in which a liquid crystal material having negative dielectric anisotropy and a photo-alignment film are combined.
- At least one component of the liquid crystal material is preferably a compound having an alkenyl structure.
- Examples of the compound having an alkenyl structure include compounds represented by the following formula (D-1), (D-2) or (D-3).
- n are the same or different integers, preferably 1 to 6)
- At least one component of the liquid crystal material is preferably a compound containing an alkoxy structure.
- the compound containing an alkoxy structure include compounds represented by the following formula (E-1), (E-2), (E-3), (E-4) or (E-5).
- n are the same or different integers, preferably 1 to 7.
- the radical scavenger is not particularly limited as long as it can react with the alignment film radical generated from the photo-alignment film or the alignment film radical transferred to the liquid crystal to deactivate the alignment film radical or the liquid crystal radical.
- a hindered amine compound is preferably used.
- the hindered amine compound is not highly soluble in the liquid crystal material, and on the other hand, it has a high affinity with amines and carboxylic acids present in the photo-alignment film. It is thought that it can selectively react with the alignment film radical.
- FIG. 2 is a diagram illustrating a reaction mechanism in which radicals generated from the photo-alignment film are deactivated by a hindered amine compound (radical scavenger).
- a hindered amine compound radical scavenger
- the optical functional group P AL in optical alignment film, light (energy: hv) is excited by being irradiated with an alignment film radicals R AL is generated To do.
- the hindered amine compound added to the liquid crystal material constituting the liquid crystal layer 23 can also be reacted selectively with the alignment film radicals R AL, loses alignment film radicals R AL Can be used.
- R AL represents a hydrocarbon group derived from a hindered amine compound.
- R h represents a hydrocarbon group derived from a hindered amine compound.
- the hindered amine radical is bonded to another alignment film radical RAL, and therefore both the hindered amine radical and the alignment film radical RAL disappear.
- a compound formed by combining a hindered amine radical with an alignment film radical R AL also functions as a radical scavenger, and yet another alignment film radical R Reacts with AL to generate hindered amine radicals.
- This hindered amine radical is a radical scavenger that reacts with the alignment film radical R AL as shown in the formula (A-III).
- the radical scavenger does not decrease, and the generated radical can continue to be deactivated, and the generation of ions from the radical can be inhibited for a long time. That is, according to the hindered amine compound (radical scavenger), a decrease in VHR due to exposure to backlight light can be suppressed for a long time with a small addition amount.
- the hindered amine compound has high reactivity with the radical generated from the photo-alignment film, the radical in the liquid crystal layer 23 can be quickly deactivated. Therefore, when an antioxidant is used in combination, the antioxidant can be effectively suppressed from being consumed by reacting with radicals generated from the photo-alignment film. As a result, in the liquid crystal layer Oxide generation can also be suppressed. Therefore, seizure and stains derived from the oxide can also be prevented.
- the liquid crystal display device can be driven at a low frequency, and as a result, the power consumption can be kept low.
- Examples of the hindered amine compounds include compounds represented by the following formula (F-1) or (F-2), and among them, compounds represented by the following formula (F-1) are preferably used.
- hindered amine compound represented by the formula (F-1) include, for example, the following formulas (F-1-1), (F-1-2), (F-1-3), (F- And compounds represented by 1-4) or (F-1-5).
- hindered amine compound represented by the above formula (F-2) include compounds represented by the following formula (F-2-1) or (F-2-2).
- a compound in which a hydrogen atom is substituted with a methyl group as in the following formula (F-2-3) can also be used.
- the hindered amine compound may have a structure having a radical moiety as shown in the following formula (F-3). Specific examples thereof include, for example, the following formulas (F-3-1), ( And a structure represented by (F-3-2) or (F-3-3).
- the concentration of the radical scavenger (hindered amine compound) is preferably 1 ppm or more and 1000 ppm or less. Within this range, radicals generated from the photo-alignment film can be sufficiently deactivated, and the effect of suppressing the reduction in VHR can be obtained particularly sufficiently.
- the radical of a hindered amine can exist stably, when the density
- a more preferable upper limit of the concentration of the radical scavenger (hindered amine compound) is 500 ppm, and a more preferable upper limit is 250 ppm.
- the liquid crystal layer 23 may further contain an antioxidant.
- the antioxidant is not particularly limited as long as it has higher reactivity with respect to oxygen or oxide than the liquid crystal material.
- a phenol-based antioxidant is preferably used.
- FIG. 3 is a diagram illustrating the action of the phenolic antioxidant in the present invention.
- equation (1) in FIG. 3 when oxygen enters the liquid crystal panel and light or heat energy is applied, the alkyl group (R) contained in the liquid crystal material, the alignment film, and the seal material is oxidized. This produces an oxidizing substance (ROOH). Radicals are generated from this oxidized substance, and the radicals are ionized under the condition that no antioxidant or radical scavenger is present.
- ROOH oxidizing substance
- the oxidized material dissociated from the polymer constituting the alignment film or the sealant is ionized and eluted into the liquid crystal layer 23. Ions are generated inside. Therefore, the VHR is lowered by the ions in the liquid crystal layer 23.
- an antioxidant as shown in the formulas (2) and (3) of FIG. 3, before the radical is ionized, the antioxidant reacts with the radical, and the liquid crystal material, the photo-alignment film, and It is possible to prevent generation of ions due to oxidation of the sealing material. Further, in the cycle shown in the formulas (2) and (3) in FIG. 3, the amount of the antioxidant is not decreased, so that radical ionization can be prevented over a long period of time.
- the antioxidant has a function of desorbing (reducing) oxygen from the oxide by repeating a cycle of desorption of hydrogen group ⁇ addition ⁇ desorption. It suppresses deterioration (decomposition and ionization) caused by However, the antioxidant may be consumed by a reaction between the antioxidant and the photo-alignment film.
- FIG. 4 is a diagram illustrating the reaction between the phenolic antioxidant and the photoreactive film. As shown in FIG. 4, when the cinnamate group, which is a photofunctional group, is cleaved by the ultraviolet light of the backlight and a radical is generated, the antioxidant reacts with the radical, whereby the antioxidant itself is radicalized.
- the radicalized antioxidant may be combined with radicals on the photo-alignment film side generated by cleavage of the cinnamate group.
- the antioxidant bonded to the radical on the photo-alignment film side cannot return to the antioxidant again, the amount of the antioxidant in the liquid crystal layer 23 gradually decreases.
- the cinnamate group is described as an example, but it is known that the consumption of the antioxidant similarly occurs when another photofunctional group such as an azobenzene group is used.
- the antioxidant is prevented from being consumed by using the antioxidant in combination with the radical scavenger.
- the radical scavenger has a function of trapping radicals in the alignment film and the liquid crystal, and prevents radical ionization by repeatedly capturing and releasing radicals.
- the radical scavenger which has higher reactivity with radicals than the antioxidant, keeps scavenging radicals in the photo-alignment film and liquid crystal, so that the reaction that consumes the antioxidant can be suppressed. It is thought that it can continue maintaining.
- phenolic antioxidant examples include those represented by the following formula (G). More specifically, for example, the following formula (G-1), (G-2) or (G-3) ).
- n is an integer, preferably 3 to 20.
- phenolic antioxidant represented by the above formula (G) include, for example, the following formulas (Ga), (Gb), (Gc), (Gd), (G -E), a compound represented by (Gf) or (Gg).
- the concentration of the antioxidant is preferably 1 ppm or more and 10% by weight or less. Within this range, oxygen that has entered the liquid crystal panel from the outside can be prevented from oxidizing the liquid crystal material, so that display burn-in and spots caused by the oxide can be effectively prevented.
- an antioxidant can partially deactivate radicals generated from the photo-alignment film, so that the effect of suppressing the reduction in VHR can be obtained particularly sufficiently.
- a more preferred lower limit of the concentration is 10 ppm, a more preferred upper limit is 5% by weight, and a still more preferred upper limit is 1% by weight.
- the alignment mode of the liquid crystal panel is not particularly limited.
- a horizontal alignment mode such as a fringe field switching (FFS) mode, an in-plane switching (IPS) mode, or the like; vertical alignment Mode; Twisted Nematic (TN) mode can be used.
- FFS fringe field switching
- IPS in-plane switching
- TN Twisted Nematic
- the alignment mode of the liquid crystal panel is a horizontal alignment mode
- radicals are easily generated from the photo-alignment film, so that the effect of adding a radical scavenger can be obtained remarkably. That is, in the vertical alignment mode photo-alignment process (polarized UV irradiation), the pretilt angle only needs to be slightly tilted from 90 °, but in the horizontal alignment mode photo-alignment process, the orientation of the liquid crystal alignment (the direction in the substrate plane) ) Must be controlled with higher accuracy. Therefore, the irradiation amount in the photo-alignment process in the horizontal alignment mode is usually larger by one digit or more than in the vertical alignment mode, and more radicals are likely to be generated due to side reactions than in the vertical alignment mode. Since the radical scavenger contained in the liquid crystal layer can deactivate radicals generated during the photo-alignment treatment, it is possible to effectively prevent radicals from remaining after completion of the liquid crystal panel (after liquid crystal injection).
- At least one substrate 21 is provided with a structure (FFS electrode structure) including a planar electrode, a slit electrode, and an insulating film disposed between the planar electrode and the slit electrode.
- An oblique electric field is formed in the adjacent liquid crystal layer 23.
- the slit electrode, the insulating film, and the planar electrode are arranged in this order from the liquid crystal layer 23 side.
- the slit electrode for example, a slit having a linear opening surrounded by the electrode around the entire circumference, or a linear notch provided with a plurality of comb teeth and disposed between the comb teeth.
- the comb-shaped thing which comprises a slit can be used.
- a pair of comb electrodes are provided on at least one substrate 21, and a lateral electric field is formed in the liquid crystal layer 23 adjacent to the substrate 21.
- the pair of comb-shaped electrodes for example, an electrode pair that includes a plurality of comb-tooth portions and is arranged so that the comb-tooth portions mesh with each other can be used.
- the pair of substrates 21 are usually bonded to each other by a sealing material (not shown) provided so as to surround the periphery of the liquid crystal layer 23, and the liquid crystal layer 23 is held in a predetermined region. Is done.
- a sealing material for example, an epoxy resin containing an inorganic filler or an organic filler and a curing agent can be used.
- polarizing plates linear polarizers
- a typical example of the polarizing plate is a polyvinyl alcohol (PVA) film obtained by adsorbing and orienting an anisotropic material such as an iodine complex having dichroism.
- PVA polyvinyl alcohol
- a protective film such as a triacetyl cellulose film is laminated on both sides of the PVA film and put to practical use.
- An optical film such as a retardation film may be disposed between the polarizing plate and the pair of substrates 21.
- a backlight 10 is disposed on the back side of the liquid crystal panel.
- a liquid crystal display device having such a configuration is generally called a transmissive liquid crystal display device.
- the backlight 10 is not particularly limited as long as it emits light including visible light, may emit light including only visible light, and emits light including both visible light and ultraviolet light. It may be.
- a backlight 10 that emits white light is preferably used.
- a light emitting diode (LED) is preferably used.
- visible light means light (electromagnetic wave) having a wavelength of 380 nm or more and less than 800 nm.
- the present invention is characterized in that radicals generated from the photo-alignment film by being exposed to light from the backlight 10 are deactivated by a radical scavenger. Therefore, the radical scavenger can function effectively when at least part of the emission spectrum of the backlight 10 overlaps with at least part of the absorption spectrum of the photo-alignment film.
- the liquid crystal display device includes an external circuit such as a TCP (tape carrier package) and a PCB (printed wiring board) in addition to the liquid crystal panel 20 and the backlight 10; opticals such as a viewing angle widening film and a brightness enhancement film.
- Film It is comprised by several members, such as a bezel (frame), and may be integrated in the other member depending on the member. Members other than those already described are not particularly limited, and those normally used in the field of liquid crystal display devices can be used, and thus description thereof is omitted.
- a fringe field switching mode (FFS mode) liquid crystal panel was actually fabricated by the following method. First, a TFT substrate having a TFT, FFS electrode structure, and the like, and a color filter substrate (CF substrate) having a black matrix, a color filter, and the like were prepared. Then, an alignment film solution was applied on the surface of each of the TFT substrate and the CF substrate. The solid content of the alignment film solution was a polymer material containing a polyamic acid structure and a photoreactive azobenzene structure in the main chain.
- both substrates were heated at 70 ° C. in order to volatilize the solvent in the alignment film solution.
- the surfaces of both substrates were irradiated with linearly polarized light having a dominant wavelength of 365 nm at an intensity of 2000 mJ / cm 2 .
- the polarization direction of the linearly polarized light was set to be orthogonal to the direction in which the liquid crystal is aligned. Irradiation with linearly polarized light caused a trans-cis isomerization reaction in the azobenzene structure, and the orientation regulating power was expressed.
- the trans form of the azobenzene structure has the structure shown in the following (B-5-1), and the cis form has the structure shown in the following (B-5-2).
- substrates were heated at 220 degreeC as this baking.
- imidization dehydration ring closure reaction
- a horizontal alignment film in which sufficient alignment regulating force was expressed by light irradiation was obtained.
- the film thickness after the main firing was 100 nm.
- a liquid crystal composition was dropped on the TFT substrate, and a heat / visible light sealing material was drawn on the CF substrate with a dispenser. Then, the TFT substrate and the CF substrate were bonded together, and the liquid crystal composition was sealed between the substrates. At the time of bonding the substrates, the display area was shielded from light and exposure for curing the sealing material was performed.
- liquid crystal composition a liquid crystal material containing a compound having an alkenyl structure represented by the following formula (D-1-1) and a hindered amine compound (radical scavenger) represented by the following formula (F-1-2) is used. It was. The concentration of the hindered amine compound was 200 ppm with respect to the total amount of the liquid crystal composition.
- the liquid crystal molecules were realigned by heating at 130 ° C. for 40 minutes. Then, a pair of polarizing plates are provided on the back surface side of the TFT substrate (backlight light incident surface side) and the CF substrate observation surface side (backlight light emission surface side) so that the polarization axes have a crossed Nicols relationship. Was pasted. As described above, an FFS mode liquid crystal panel was produced. Then, the backlight provided with white LED was attached to the back side of a liquid crystal panel, and the liquid crystal display device of Example 1 was completed.
- Example 1 A liquid crystal panel for FFS mode was produced in the same manner as in Example 1 except that the hindered amine compound was not added to the liquid crystal composition.
- Comparative Example 2 In place of the photo-alignment film that expresses alignment regulating force by light irradiation, except that a rubbing alignment film that expresses alignment regulating force is formed by rubbing treatment, and no hindered amine compound is added to the liquid crystal composition. In the same manner as in Example 1, a liquid crystal panel for FFS mode was produced. In Comparative Example 2, a polymer material containing a polyamic acid structure in the main chain was used as the solid content of the alignment film solution. Moreover, the rubbing process was implemented without implementing the photo-alignment process.
- Example 1 The liquid crystal panels produced in Example 1 and Comparative Examples 1 and 2 were continuously energized with the backlight turned on, and changes in voltage holding ratio over time were confirmed.
- FIG. 5 is a graph showing the change over time in the voltage holding ratio of the liquid crystal panels of Example 1 and Comparative Examples 1 and 2.
- Example 1 and Comparative Example 1 indicate that the decrease in the voltage holding ratio could be suppressed by adding the hindered amine compound to the liquid crystal material.
- the comparison result of the comparative example 1 and the comparative example 2 has shown that the remarkable fall of the voltage holding ratio which arose in the comparative example 1 originates in a photo-alignment film. That is, the effect confirmed in Example 1 became clear in the combination of a radical scavenger (hindered amine compound) and a photo-alignment film.
- the reason why the voltage holding ratio decreases due to the photo-alignment film is considered as follows.
- the azobenzene structure contained in the photo-alignment film used in Example 1 and Comparative Example 1 is subjected to an alignment treatment with light having a wavelength of 365 nm close to the visible light region.
- the backlight of the liquid crystal display device mainly emits light in the visible light region for color display. From the results of Comparative Example 1, the short wavelength side of the emission spectrum of the backlight and the length of the absorption spectrum of the azobenzene structure are shown. Although it is difficult to detect by the actual spectrum analysis, the wavelength side is slightly overlapped, and it is assumed that radicals are generated.
- cinnamate, chalcone, coumarin, stilbene, a phenol ester, etc. are mentioned as a photoreaction site
- a liquid crystal component having an alkenyl structure is effective for reducing the viscosity of the liquid crystal material.
- the double bond contained in the alkenyl structure is easily attacked by radicals, when used in combination with a photo-alignment film that can be a radical generation source, it tends to cause a decrease in VHR.
- the addition of a hindered amine compound to the liquid crystal material can effectively prevent radical attack on the alkenyl structure.
- the liquid crystal component having an alkenyl structure is not limited to a liquid crystal material having a negative dielectric anisotropy but a liquid crystal material having a positive dielectric anisotropy from the viewpoint of improving the response speed of the liquid crystal display device. Is also preferably added.
- Example 2 A liquid crystal display device including an FFS mode liquid crystal panel was actually produced by the following method. First, a TFT substrate having a TFT, FFS electrode structure, and the like, and a CF substrate having a black matrix, a color filter, and the like were prepared. Then, an alignment film solution was applied on the surface of each of the TFT substrate and the CF substrate. The solid content of the alignment film solution was a polymer material containing a polyamic acid structure obtained by polymerizing an acid anhydride of the following formula (B-7-1) and an amine compound of the following formula (B-7-2). . The hydrogen atom of cyclobutane in the acid anhydride of the following formula (B-7-1) may be replaced with another atom or functional group.
- both substrates were heated at 70 ° C. in order to volatilize the solvent in the alignment film solution.
- both substrates were heated at 230 ° C. for the main firing.
- imidization dehydration ring closure reaction
- the surfaces of both substrates were irradiated with linearly polarized light having a dominant wavelength of 254 nm at an intensity of 600 mJ / cm 2 .
- the polarization direction of the linearly polarized light was set to be orthogonal to the direction in which the liquid crystal is aligned.
- a liquid crystal composition was dropped on the TFT substrate, and a heat / visible light sealing material was drawn on the CF substrate with a dispenser. Then, the TFT substrate and the CF substrate were bonded together, and the liquid crystal composition was sealed between the substrates. At the time of bonding the substrates, the display area was shielded from light and exposure for curing the sealing material was performed.
- a hindered amine compound (radical scavenger) of the same formula (F-1-2) as in Example 1 is added to a liquid crystal material containing a compound having an alkoxy structure of the following formula (E-3-1). What was added was used.
- the concentration of the hindered amine compound was 200 ppm with respect to the total amount of the liquid crystal composition.
- the liquid crystal molecules were realigned by heating at 130 ° C. for 40 minutes. Then, a pair of polarizing plates are provided on the back surface side of the TFT substrate (backlight light incident surface side) and the CF substrate observation surface side (backlight light emission surface side) so that the polarization axes have a crossed Nicols relationship.
- a pair of polarizing plates are provided on the back surface side of the TFT substrate (backlight light incident surface side) and the CF substrate observation surface side (backlight light emission surface side) so that the polarization axes have a crossed Nicols relationship.
- the backlight provided with white LED was attached to the back side of a liquid crystal panel, and the liquid crystal display device of Example 2 was completed.
- Comparative Example 3 A liquid crystal display device of Comparative Example 3 was produced in the same manner as in Example 2 except that the hindered amine compound was not added to the liquid crystal composition.
- the cyclobutane structure contained in the photo-alignment film used in Example 2 usually absorbs light having a wavelength of 300 nm or less, thereby generating radicals in the intermediate stage of the reaction.
- a photo-alignment film containing a cyclobutane structure may be improved to a structure with good light absorption in order to reduce the amount of exposure during the alignment process, for example, a film having a high light absorption in the skeleton of the diamine moiety.
- the absorbed light energy transitions to a cyclobutane moiety to promote photocleavage of the cyclobutane moiety.
- the absorbance for light on the longer wavelength side increases, but the short wavelength side of the emission spectrum of the backlight may overlap with the long wavelength side of the absorption spectrum of the photo-alignment film. is there.
- the exposure amount during the alignment treatment is as large as several hundred mJ / cm 2 or more, some of the radicals generated during the alignment treatment may not be deactivated even after the liquid crystal panel is completed. Therefore, even in the decomposition type photo-alignment film having a cyclobutane structure, there is a cause of occurrence of image sticking, and it was confirmed that image sticking occurred in the liquid crystal display device of Comparative Example 3.
- the hindered amine compound can effectively deactivate radicals generated by the reaction of the photo-alignment film and prevent seizure.
- the alkoxy structure in the liquid crystal material used in Example 2 is preferably used for adjusting the magnitude of the dielectric anisotropy of the liquid crystal material having negative dielectric anisotropy (negative liquid crystal).
- size of dielectric anisotropy can be adjusted easily, without using an alkoxy group.
- VHR tends to be low when a liquid crystal material containing an alkoxy structure is used, and this tendency is particularly remarkable when combined with a photo-alignment film.
- a radical scavenger is added to the VHR, the decrease in VHR can be suppressed. The reason can be explained by the following hypothesis models 1 to 4.
- the following formula represents a part of a compound having an alkoxy structure, and shows three resonance structures corresponding to the alkoxy structure.
- the resonance structure (a) shown in the center and the resonance structure (b) shown on the right are in an ionic state, which causes a decrease in VHR.
- the resonance structures (a) and (b) are changed to structures (a ′) and (b ′) having a peroxide structure by the presence of oxygen, respectively.
- the structures (a ′) and (b ′) having a peroxide structure are easily radicalized as shown in (a ′′) and (b ′′), respectively.
- the generated radicals are ionized to cause a reduction in VHR.
- a negative liquid crystal containing an alkoxy structure is composed of a highly polarized molecular structure, so the solubility of impurity ions is higher than that of positive liquid crystals, and mobile ions are likely to exist in the liquid crystal. Mobile ions have the effect of canceling the charged charge, resulting in a decrease in VHR.
- the above hypothetical models 1 to 3 involve radicals and can be countered by capturing radicals with a radical scavenger.
- Hypothesis model 4 explains that negative liquid crystals are more affected by ionic impurities generated through radical generation than positive liquid crystals, and radical trapping is indirectly a hypothesis model. It is also a measure for 4. From the above, by containing a radical scavenger in the liquid crystal layer, it is possible to obtain an effect of suppressing a decrease in VHR that occurs when a liquid crystal material containing an alkoxy structure is used.
- Example 3 A liquid crystal display device including an FFS mode liquid crystal panel was actually produced by the following method. First, a TFT substrate having a TFT, FFS electrode structure, and the like, and a CF substrate having a black matrix, a color filter, and the like were prepared. Then, an alignment film solution was applied on the surface of each of the TFT substrate and the CF substrate. The solid content of the alignment film solution was a polymer material having a polysiloxane structure as a main skeleton and a photofunctional group in the side chain and a cinnamate group of the following formula (B-1).
- both substrates were heated at 70 ° C. in order to volatilize the solvent in the alignment film solution. Subsequently, both substrates were heated at 230 ° C. for the main firing. Thereafter, as a photo-alignment treatment, the surfaces of both substrates were irradiated with linearly polarized light having a dominant wavelength of 313 nm with an intensity of 200 mJ / cm 2 .
- the polarization direction of the linearly polarized light was set to be orthogonal to the direction in which the liquid crystal is aligned.
- an isomerization reaction and a dimerization reaction occurred in the cinnamate group, and an orientation regulating force was expressed.
- a horizontal alignment film in which sufficient alignment regulating force was expressed by light irradiation was obtained.
- the film thickness after the main firing was 100 nm.
- a liquid crystal composition was dropped on the TFT substrate, and a heat / visible light sealing material was drawn on the CF substrate with a dispenser. Then, the TFT substrate and the CF substrate were bonded together, and the liquid crystal composition was sealed between the substrates. At the time of bonding the substrates, the display area was shielded from light and exposure for curing the sealing material was performed.
- a hindered amine compound (radical scavenger) of the following formula (F-1-5) is added to a liquid crystal material containing the same compound having the alkenyl structure of the above formula (D-1-1) as in Example 1.
- the antioxidant of the following formula (Gg) was used.
- the concentration of the hindered amine compound was 200 ppm with respect to the total amount of the liquid crystal composition.
- the concentration of the antioxidant was 0.1% by weight with respect to the total amount of the liquid crystal composition.
- the liquid crystal molecules were realigned by heating at 130 ° C. for 40 minutes. Then, a pair of polarizing plates are provided on the back surface side of the TFT substrate (backlight light incident surface side) and the CF substrate observation surface side (backlight light emission surface side) so that the polarization axes have a crossed Nicols relationship.
- a pair of polarizing plates are provided on the back surface side of the TFT substrate (backlight light incident surface side) and the CF substrate observation surface side (backlight light emission surface side) so that the polarization axes have a crossed Nicols relationship.
- the backlight provided with white LED was attached to the back side of a liquid crystal panel, and the liquid crystal display device of Example 3 was completed.
- Comparative Example 4 A liquid crystal display device of Comparative Example 4 was produced in the same manner as in Example 3 except that the hindered amine compound and the antioxidant were not added to the liquid crystal composition.
- Example 4 A liquid crystal display device including an FFS mode liquid crystal panel was actually produced by the following method. First, a TFT substrate having a TFT, FFS electrode structure, and the like, and a CF substrate having a black matrix, a color filter, and the like were prepared. Then, an alignment film solution was applied on the surface of each of the TFT substrate and the CF substrate. The solid content of the alignment film solution was a polymer material having a polysiloxane structure as a main skeleton and a cinnamate group as a photofunctional group in the side chain.
- both substrates were heated at 70 ° C. in order to volatilize the solvent in the alignment film solution. Subsequently, both substrates were heated at 230 ° C. for the main firing. Thereafter, as a photo-alignment treatment, the surfaces of both substrates were irradiated with linearly polarized light having a dominant wavelength of 313 nm with an intensity of 20 mJ / cm 2 .
- the polarization direction of the linearly polarized light was set to be orthogonal to the direction in which the liquid crystal is aligned.
- a horizontal alignment film in which the alignment regulating force was expressed by light irradiation was obtained.
- the film thickness after the main firing was 100 nm.
- the exposure amount during the photo-alignment treatment was reduced, but as described later, the photopolymerizable monomer added to the liquid crystal material was aligned.
- the orientation regulating force was improved by polymerizing on the film surface.
- a liquid crystal composition was dropped on the TFT substrate, and a heat / visible light sealing material was drawn on the CF substrate with a dispenser. Then, the TFT substrate and the CF substrate were bonded together, and the liquid crystal composition was sealed between the substrates. At the time of bonding the substrates, the display area was shielded from light and exposure for curing the sealing material was performed.
- the same photopolymerizable monomer represented by the following formula (C-1-1) as Example 1 was added to the liquid crystal material containing the compound having the alkenyl structure represented by the above formula (D-1-1) as in Example 1.
- a hindered amine compound (radical scavenger) of the above formula (F-1-5) and an antioxidant of the above formula (Gg) were added.
- the blending amount of the photopolymerizable monomer was 0.25 wt% with respect to the total amount of the liquid crystal composition.
- the concentration of the hindered amine compound was 200 ppm with respect to the total amount of the liquid crystal composition.
- the concentration of the antioxidant was 0.1% by weight with respect to the total amount of the liquid crystal composition.
- a monomer other than the monomer represented by the formula (C-1-1) may be used as the photopolymerizable monomer.
- the monomer of the formula (C-1-1) the monomer of the formula (C-1-2) in which the terminal methacrylate group is changed to an acrylate group, or the formula (C-1-2) in which the skeleton portion is changed to phenanthrene A monomer of C-1-3) may be used.
- hydrogen atoms present in the skeleton may be independently replaced with halogen atoms. .
- the display area of the liquid crystal panel was irradiated with black light with an intensity of 3000 mJ / cm 2 .
- the photopolymerizable monomer in the liquid crystal layer was polymerized on the alignment film surface while taking in liquid crystal molecules.
- the liquid crystal alignment on the surface of the alignment film was fixed by the polymer of the photopolymerizable monomer, and a sufficient alignment regulating force could be obtained.
- the liquid crystal molecules were realigned by heating at 130 ° C. for 40 minutes. Then, a pair of polarizing plates are provided on the back surface side of the TFT substrate (backlight light incident surface side) and the CF substrate observation surface side (backlight light emission surface side) so that the polarization axes have a crossed Nicols relationship.
- a pair of polarizing plates are provided on the back surface side of the TFT substrate (backlight light incident surface side) and the CF substrate observation surface side (backlight light emission surface side) so that the polarization axes have a crossed Nicols relationship.
- the backlight provided with white LED was attached to the back side of the liquid crystal panel, and the liquid crystal display device of Example 4 was completed.
- Comparative Example 5 A liquid crystal display device of Comparative Example 5 was produced in the same manner as in Example 4 except that the hindered amine compound and the antioxidant were not added to the liquid crystal composition.
- the photopolymerizable monomer used in Example 4 and Comparative Example 5 becomes a radical generation source. Therefore, in Example 4 and Comparative Example 5, in addition to the photo-alignment film, a photopolymerizable monomer is present as a radical generation source, and the conditions are such that radicals are easily generated in the liquid crystal layer.
- a photopolymerizable monomer is present as a radical generation source, and the conditions are such that radicals are easily generated in the liquid crystal layer.
- a hindered amine compound to the liquid crystal material, not only radicals generated by the reaction of the photo-alignment film but also photopolymerizable monomers remaining after the PSA treatment can be effectively deactivated.
- the same effect can be acquired also by adding antioxidant to liquid crystal material. From the above, unevenness occurred in the liquid crystal display device of Comparative Example 5, but unevenness could be effectively prevented in the liquid crystal display device of Example 4.
- One embodiment of the present invention includes an active matrix liquid crystal panel and a backlight.
- the liquid crystal panel includes a liquid crystal layer, a pair of substrates that sandwich the liquid crystal layer, and a surface of the pair of substrates on the liquid crystal layer side.
- the alignment film is a photo-alignment film formed from a material exhibiting photo-alignment, and the liquid crystal layer is a liquid crystal material and a liquid crystal containing a radical scavenger. It may be a display device.
- the radical eluted in the liquid-crystal layer can be deactivated with a radical scavenger, and the fall of VHR can be prevented. As a result, a good VHR can be maintained over a long period of time using the photo-alignment film, and image sticking and spots on the display screen can be prevented.
- the radical scavenger preferably contains a compound represented by the following formula (1). If a hindered amine compound of the following formula (1) is used as a radical scavenger, radicals can be kept inactivated by a cyclic cycle. Therefore, a small amount of addition suppresses VHR reduction due to exposure to backlight for a long period of time. be able to. Moreover, since the reactivity with a radical is high, the radical in a liquid-crystal layer can be deactivated rapidly.
- the liquid crystal layer may further contain an antioxidant, and a compound represented by the following formula (2) is suitably used as the antioxidant.
- an antioxidant By containing the antioxidant, the oxygen that has entered the liquid crystal panel oxidizes the alkyl group (R) contained in the liquid crystal, the alignment film, and the sealing material, and radicals generated from this oxidizing substance cause a decrease in VHR. This can be prevented.
- the photo-alignment film examples include those containing at least one photoreactive site selected from the group consisting of cinnamate, chalcone, coumarin, stilbene, azobenzene, and phenol ester.
- the photo-alignment film may be a polymer obtained by polymerizing a monomer containing an acid anhydride represented by the following formula (3).
- the long wavelength side of the absorption spectrum overlaps the short wavelength side of the emission spectrum of the backlight, and radicals are generated when irradiated with the light of the backlight. Therefore, when the radical scavenger is applied, the effect of preventing the decrease in VHR can be sufficiently obtained.
- a compound having an alkenyl structure may be used as at least one component of the liquid crystal material, and the compound having the alkenyl structure may be represented by the following formula (4-1), (4-2), or (4-3). The compound which is made is mentioned.
- a liquid crystal component having an alkenyl structure is effective in reducing the viscosity of the liquid crystal material, but a double bond contained in the alkenyl structure is easily attacked by radicals. Therefore, when the radical scavenger is applied, the effect of preventing the decrease in VHR can be sufficiently obtained.
- the liquid crystal material may have a negative dielectric anisotropy.
- a liquid crystal material having negative dielectric anisotropy defects of image sticking and spots tend to appear more obvious than when using a liquid crystal material having positive dielectric anisotropy. It was in. Therefore, when the radical scavenger is applied, the effect of preventing the decrease in VHR can be obtained more sufficiently.
- At least one component of the liquid crystal material may be a compound containing an alkoxy structure.
- the compound containing the alkoxy structure include the following formulas (5-1), (5-2), (5-3), ( And compounds represented by 5-4) or (5-5).
- Alkoxy structures (especially methoxy and ethoxy groups) include an ionic state in the resonance structure, which causes a reduction in VHR. Therefore, it is required to prevent further reduction in VHR by applying a radical scavenger.
- a fringe field switching mode or an in-plane switching mode is preferably used.
- the irradiation amount in the horizontal alignment mode photo-alignment treatment is usually more than an order of magnitude higher than in the vertical alignment mode, More radicals are more likely to be generated by side reactions than in the vertical alignment mode. Therefore, when the radical scavenger is applied, the effect of preventing the decrease in VHR can be sufficiently obtained.
- the liquid crystal panel may have a layer containing a polymer obtained by polymerizing a photopolymerizable monomer represented by the following formula (6) on the liquid crystal layer side surface of the alignment film.
- Y in the formula (6) include structures represented by the following formula (7-1), (7-2) or (7-3).
- A1-Y-A2 (6) (In the formula, Y represents a structure containing at least one benzene ring and / or a condensed benzene ring, and a hydrogen atom in the benzene ring and the condensed benzene ring may be replaced by a halogen atom, and A1 and A2 At least one represents acrylate or methacrylate, and A1 and A2 are directly bonded to the benzene ring or the condensed benzene ring.
- a hydrogen atom may be replaced by a halogen atom.
Abstract
Description
(1)ラジカル発生
液晶パネルにバックライトの光(エネルギー量:hν)が照射されることで、下記式(A-I)に示したように、光配向膜に含まれる光官能基が励起され、光官能基が開裂することによってラジカルが発生する。特に高輝度化したバックライトを用いた場合には、ラジカルの発生が顕著になる。
光配向膜中で発生したラジカルが液晶層に溶出し、溶出したラジカルがイオン化する。
(2-2)第二のイオン生成
光配向膜中で発生したラジカルが液晶層に溶出し、ラジカルが光官能基から液晶分子に転移し、液晶分子がイオン化する。
(3)電圧保持率の低下
液晶層中のイオンが、液晶パネルの画面の端部や、ボックスパターン表示の端部に溜まり、その部分の電圧保持率(VHR)が低下することにより、上述した焼き付き及びシミが発生する。
A1-Y-A2 (C)
(式中、Yは、少なくとも1つのベンゼン環及び/又は縮合ベンゼン環を含む構造を表し、上記ベンゼン環及び上記縮合ベンゼン環中の水素原子はハロゲン原子に置き換えられていてもよく、A1及びA2の少なくとも一方は、アクリレート又はメタクリレートを表し、A1及びA2は、上記ベンゼン環又は上記縮合ベンゼン環に直接結合している。)
<液晶材料>
液晶材料は、下記式(P)で定義される誘電率異方性(Δε)が負の値を有するものであってもよく、正の値を有するものであってもよい。すなわち、液晶材料は、負の誘電率異方性を有するものであってもよく、正の誘電率異方性であってもよい。負の誘電率異方性を有する液晶材料としては、例えば、Δεが-1~-20のものを用いることができる。正の誘電率異方性を有する液晶材料としては、例えば、Δεが1~20のものを用いることができる。
Δε=(長軸方向の誘電率)-(短軸方向の誘電率) (P)
ラジカル捕捉剤は、光配向膜から発生した配向膜ラジカルや、その配向膜ラジカルが液晶に転移した液晶ラジカルと反応し、配向膜ラジカルや液晶ラジカルを失活させるものであれば特に限定されず、例えば、ヒンダードアミン化合物が好適に用いられる。ヒンダードアミン化合物は、液晶材料への溶解性が高くなく、一方で、光配向膜中に存在するアミンやカルボン酸との親和性が高いため、配向膜付近に偏在しやすく、光配向膜から発生した配向膜ラジカルと選択的に反応できると考えられる。
液晶層23は、更に酸化防止剤を含有してもよい。酸化防止剤としては、液晶材料よりも酸素又は酸化物に対する反応性が高いものであれば特に限定されず、例えば、フェノール系酸化防止剤が好適に用いられる。
フリンジ・フィールド・スイッチングモード(FFSモード)の液晶パネルを以下の方法により実際に作製した。
まず、TFT、FFS電極構造等を備えるTFT基板、及び、ブラックマトリクス、カラーフィルタ等を備えるカラーフィルタ基板(CF基板)を用意した。そして、TFT基板及びCF基板の各々の表面上に、配向膜溶液を塗布した。配向膜溶液の固形分は、主鎖中に、ポリアミック酸構造と、光反応性を有するアゾベンゼン構造を含むポリマー材料であった。
液晶組成物中にヒンダードアミン化合物を添加しなかったこと以外は、実施例1と同様にして、FFSモード用の液晶パネルを作製した。
光照射により配向規制力が発現する光配向膜に代えて、ラビング処理により配向規制力が発現するラビング配向膜を形成したこと、及び、液晶組成物中にヒンダードアミン化合物を添加しなかったこと以外は、実施例1と同様にして、FFSモード用の液晶パネルを作製した。
比較例2では、配向膜溶液の固形分として、主鎖中にポリアミック酸構造を含むポリマー材料を用いた。また、光配向処理は実施せず、ラビング処理を実施した。
実施例1及び比較例1、2で作製した液晶パネルを、バックライトを点灯させた状態で通電し続け、電圧保持率の経時変化を確認した。図5は、実施例1及び比較例1、2の液晶パネルの電圧保持率の経時変化を示したグラフである。
実施例1及び比較例1で用いた光配向膜に含まれるアゾベンゼン構造は、可視光領域に近い波長365nmの光によって配向処理されるものである。一方、液晶表示装置のバックライトは、カラー表示のために主に可視光領域の光を発するが、比較例1の結果から、バックライトの発光スペクトルの短波長側とアゾベンゼン構造の吸収スペクトルの長波長側とが、実際のスペクトル分析では検出が難しいレベルではあるものの、わずかながら重なっており、ラジカルが発生しているものと推察される。例えば、下記の反応式に示したように、バックライトの光によってアゾベンゼン構造において光開裂反応が生じることが考えられる。これに対して、実施例1の結果から、ヒンダードアミン化合物が、光配向膜の反応によって生じたラジカルを効果的に失活させ、電圧保持率の低下を防止できることが分かった。
FFSモードの液晶パネルを備える液晶表示装置を、以下の方法により実際に作製した。
まず、TFT、FFS電極構造等を備えるTFT基板、及び、ブラックマトリクス、カラーフィルタ等を備えるCF基板を用意した。そして、TFT基板及びCF基板の各々の表面上に、配向膜溶液を塗布した。配向膜溶液の固形分は、下記式(B-7-1)の酸無水物と下記式(B-7-2)のアミン化合物を重合して得られるポリアミック酸構造を含むポリマー材料であった。なお、下記式(B-7-1)の酸無水物中のシクロブタンの水素原子は、他の原子や官能基に置き換えられていてもよい。
液晶組成物中にヒンダードアミン化合物を添加しなかったこと以外は、実施例2と同様にして、比較例3の液晶表示装置を作製した。
実施例2及び比較例3で作製した液晶表示装置を、バックライトを点灯させた状態で通電し続けた。このとき、液晶表示装置の画面には、黒色の背景に白色のボックスパターンを表示させた。500時間後に、画面全体を64階調のグレー表示にしたところ、比較例3の液晶表示装置では、ボックスパターンの周囲にシミ状の焼き付きが観察された。一方、実施例2の液晶表示装置では、そのような焼き付きは観察されなかった。
下記反応式に示したように、アルコキシ構造(-OR)は、光配向膜から発生したラジカルRALの攻撃を受けやすく、4パターンのラジカル生成反応を生じる。発生したラジカルがイオン化することで、VHRの低下が引き起こされる。
下記反応式に示したように、光配向膜から発生したラジカルRALは、液晶層中の酸素と結合してペルオキシド構造(ROO・)を形成する。アルコキシ構造(-OR)は、ペルオキシド構造の攻撃を受けやすく、5パターンのラジカル生成反応を生じる。また、各パターンにおいて、ラジカル生成反応後にも、連鎖的に別のラジカル生成反応が繰り返される。発生したラジカルがイオン化することで、VHRの低下が引き起こされる。なお、このペルオキシド構造を経たラジカル連鎖反応は、自動酸化反応として知られる。
アルコキシ構造(特にメトキシ、エトキシ基)は、電子供与基であり、光曝露下では共鳴構造を取る。下記式は、アルコキシ構造を有する化合物の一部を表しており、アルコキシ構造に対応した3つの共鳴構造を示している。このうち、中央に示された共鳴構造(a)、及び、右に示された共鳴構造(b)はイオン状態であることから、VHRを低下させる原因となる。更に、共鳴構造(a)及び(b)はそれぞれ、酸素の存在によって、ペルオキシド構造を持つ構造(a’)及び(b’)に変化する。ペルオキシド構造を持つ構造(a’)及び(b’)はそれぞれ、(a’’)及び(b’’)に示したように容易にラジカル化する。発生したラジカルがイオン化することで、VHRの低下が引き起こされる。
アルコキシ構造を含むネガ型液晶は、分極が大きい分子構造で構成されているため、不純物イオンの溶解度がポジ型液晶よりも高く、液晶中に可動イオンが存在しやすい。可動イオンは充電した電荷を打ち消す効果があるため、結果としてVHRが低下する。
FFSモードの液晶パネルを備える液晶表示装置を、以下の方法により実際に作製した。
まず、TFT、FFS電極構造等を備えるTFT基板、及び、ブラックマトリクス、カラーフィルタ等を備えるCF基板を用意した。そして、TFT基板及びCF基板の各々の表面上に、配向膜溶液を塗布した。配向膜溶液の固形分は、ポリシロキサン構造を主骨格とし、側鎖に光官能基として、下記式(B-1)のシンナメート基を含むポリマー材料であった。
液晶組成物中にヒンダードアミン化合物及び酸化防止剤を添加しなかったこと以外は、実施例3と同様にして、比較例4の液晶表示装置を作製した。
実施例3及び比較例4で作製した液晶表示装置を、バックライトを点灯させた状態で通電し続けた。このとき、液晶表示装置の画面全体を白表示にした。500時間後に、画面全体を64階調のグレー表示にしたところ、比較例4の液晶表示装置では、画面の端にシミ状のムラが観察された。このムラは、VHRの低下が原因であると考えられる。一方、実施例3の液晶表示装置では、そのような不具合は観察されなかった。
FFSモードの液晶パネルを備える液晶表示装置を、以下の方法により実際に作製した。
まず、TFT、FFS電極構造等を備えるTFT基板、及び、ブラックマトリクス、カラーフィルタ等を備えるCF基板を用意した。そして、TFT基板及びCF基板の各々の表面上に、配向膜溶液を塗布した。配向膜溶液の固形分は、ポリシロキサン構造を主骨格とし、側鎖に光官能基としてシンナメート基を含むポリマー材料であった。
液晶組成物中にヒンダードアミン化合物及び酸化防止剤を添加しなかったこと以外は、実施例4と同様にして、比較例5の液晶表示装置を作製した。
実施例4及び比較例5で作製した液晶表示装置を、バックライトを点灯させた状態で通電し続けた。このとき、液晶表示装置の画面全体を白表示にした。500時間後に、画面全体を64階調のグレー表示にしたところ、比較例5の液晶表示装置では、画面の端にシミ状のムラが観察された。このムラは、電圧保持率の低下が原因であると考えられる。一方、実施例4の液晶表示装置では、そのような不具合は観察されなかった。
本発明の一態様は、アクティブマトリクス型液晶パネル及びバックライトを有し、上記液晶パネルは、液晶層と、上記液晶層を挟持する一対の基板と、上記一対の基板の上記液晶層側の表面にそれぞれ配置された配向膜とを有し、上記配向膜は、光配向性を示す材料から形成された光配向膜であり、上記液晶層は、液晶材料、及び、ラジカル捕捉剤を含有する液晶表示装置であってもよい。上記態様によれば、液晶層中に溶出したラジカルをラジカル捕捉剤によって失活させることができ、VHRの低下を防止することができる。これにより、光配向膜を用いて長期にわたって良好なVHRを維持することができ、表示画面における焼き付き及びシミの発生を防止することができる。
(式中、Yは、少なくとも1つのベンゼン環及び/又は縮合ベンゼン環を含む構造を表し、上記ベンゼン環及び上記縮合ベンゼン環中の水素原子はハロゲン原子に置き換えられていてもよく、A1及びA2の少なくとも一方は、アクリレート又はメタクリレートを表し、A1及びA2は、上記ベンゼン環又は上記縮合ベンゼン環に直接結合している。)
20:液晶パネル
21:基板
22:配向膜
23:液晶層
Claims (14)
- アクティブマトリクス型液晶パネル及びバックライトを有し、
前記液晶パネルは、液晶層と、前記液晶層を挟持する一対の基板と、前記一対の基板の前記液晶層側の表面にそれぞれ配置された配向膜とを有し、
前記配向膜は、光配向性を示す材料から形成された光配向膜であり、
前記液晶層は、液晶材料、及び、ラジカル捕捉剤を含有することを特徴とする液晶表示装置。 - 前記液晶層は、更に酸化防止剤を含有することを特徴とする請求項1又は2記載の液晶表示装置。
- 前記光配向膜は、シンナメート、カルコン、クマリン、スチルベン、アゾベンゼン及びフェノールエステルからなる群より選択された少なくとも一つの光反応部位を含むことを特徴とする請求項1~4のいずれかに記載の液晶表示装置。
- 前記液晶材料の少なくとも一成分は、アルケニル構造を有する化合物であることを特徴とする請求項1~6のいずれかに記載の液晶表示装置。
- 前記液晶材料は、負の誘電異方性を有することを特徴とする請求項1~8のいずれかに記載の液晶表示装置。
- 前記液晶材料の少なくとも一成分は、アルコキシ構造を含む化合物であることを特徴とする請求項9記載の液晶表示装置。
- 前記液晶パネルの配向モードは、フリンジ・フィールド・スイッチングモード又はイン・プレーン・スイッチングモードであることを特徴とする請求項1~11のいずれかに記載の液晶表示装置。
- 前記液晶パネルは、前記配向膜の前記液晶層側の表面に、下記式(6)で表される光重合性モノマーを重合して得られたポリマーを含む層を有することを特徴とする請求項1~12のいずれかに記載の液晶表示装置。
A1-Y-A2 (6)
(式中、Yは、少なくとも1つのベンゼン環及び/又は縮合ベンゼン環を含む構造を表し、前記ベンゼン環及び前記縮合ベンゼン環中の水素原子はハロゲン原子に置き換えられていてもよく、A1及びA2の少なくとも一方は、アクリレート又はメタクリレートを表し、A1及びA2は、前記ベンゼン環又は前記縮合ベンゼン環に直接結合している。)
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CN201580046746.9A CN106796372B (zh) | 2014-08-29 | 2015-08-24 | 液晶显示装置 |
US16/215,708 US10921623B2 (en) | 2014-08-29 | 2018-12-11 | Liquid crystal display device |
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US15/506,900 A-371-Of-International US10197829B2 (en) | 2014-08-29 | 2015-08-24 | Liquid crystal display device |
US16/215,708 Continuation US10921623B2 (en) | 2014-08-29 | 2018-12-11 | Liquid crystal display device |
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WO2016192834A1 (de) * | 2015-05-29 | 2016-12-08 | Merck Patent Gmbh | Flüssigkristallines medium |
WO2018116901A1 (ja) * | 2016-12-19 | 2018-06-28 | Dic株式会社 | 重合性組成物、及び、それを用いた光学異方体 |
WO2018123180A1 (ja) * | 2016-12-26 | 2018-07-05 | Jnc株式会社 | 液晶組成物および液晶表示素子 |
WO2018151312A1 (ja) * | 2017-02-20 | 2018-08-23 | シャープ株式会社 | 液晶表示装置、電子機器 |
CN109791328A (zh) * | 2016-09-29 | 2019-05-21 | 夏普株式会社 | 液晶显示装置及液晶显示装置的制造方法 |
JP2019200315A (ja) * | 2018-05-16 | 2019-11-21 | 株式会社ジャパンディスプレイ | 液晶表示装置 |
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CN106796372B (zh) * | 2014-08-29 | 2020-10-02 | 夏普株式会社 | 液晶显示装置 |
WO2016031745A1 (ja) * | 2014-08-29 | 2016-03-03 | シャープ株式会社 | 液晶表示装置 |
CN111575023B (zh) * | 2020-06-12 | 2022-03-01 | 江苏三月科技股份有限公司 | 一种化合物添加剂及其制备的液晶取向剂、液晶取向膜 |
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- 2015-08-24 US US15/506,900 patent/US10197829B2/en active Active
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CN110291456A (zh) * | 2017-02-20 | 2019-09-27 | 夏普株式会社 | 液晶显示装置、电子机器 |
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Also Published As
Publication number | Publication date |
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CN106796372B (zh) | 2020-10-02 |
JPWO2016031744A1 (ja) | 2017-06-08 |
US10921623B2 (en) | 2021-02-16 |
US20210132421A1 (en) | 2021-05-06 |
US10197829B2 (en) | 2019-02-05 |
JP6348600B2 (ja) | 2018-06-27 |
US11435609B2 (en) | 2022-09-06 |
US20170276976A1 (en) | 2017-09-28 |
US20190113781A1 (en) | 2019-04-18 |
CN106796372A (zh) | 2017-05-31 |
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