WO2024061796A1 - Polymerisable liquid crystal medium and polymerised liquid crystal film - Google Patents

Polymerisable liquid crystal medium and polymerised liquid crystal film Download PDF

Info

Publication number
WO2024061796A1
WO2024061796A1 PCT/EP2023/075581 EP2023075581W WO2024061796A1 WO 2024061796 A1 WO2024061796 A1 WO 2024061796A1 EP 2023075581 W EP2023075581 W EP 2023075581W WO 2024061796 A1 WO2024061796 A1 WO 2024061796A1
Authority
WO
WIPO (PCT)
Prior art keywords
polymerizable
tego
compounds
optical
optical component
Prior art date
Application number
PCT/EP2023/075581
Other languages
French (fr)
Inventor
Matthew CREALLY
Jack Bradford
Stephen Mulcahy
Tara Perrett
Iain Gardiner
Original Assignee
Merck Patent Gmbh
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
Application filed by Merck Patent Gmbh filed Critical Merck Patent Gmbh
Publication of WO2024061796A1 publication Critical patent/WO2024061796A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K19/00—Liquid crystal materials
    • C09K19/52—Liquid crystal materials characterised by components which are not liquid crystals, e.g. additives with special physical aspect: solvents, solid particles
    • C09K19/58—Dopants or charge transfer agents
    • C09K19/586—Optically active dopants; chiral dopants
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • 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
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K2219/00—Aspects relating to the form of the liquid crystal [LC] material, or by the technical area in which LC material are used
    • C09K2219/03—Aspects relating to the form of the liquid crystal [LC] material, or by the technical area in which LC material are used in the form of films, e.g. films after polymerisation of LC precursor

Definitions

  • the invention relates to an optical component exhibiting a reverse or negative optical dispersion profile comprising two or more liquid crystalline polymer films, wherein the first utilized polymer film exhibits a uniform planar alignment of the polymerised LC molecules and the second polymer film adjacent to the first polymer film exhibits a cholesteric alignment of the polymerised LC molecules having a % pitch rotation through the film thickness of the second polymer film.
  • the present invention relates also to a method for its preparation.
  • These optical components may be used for purposes such as, for example, adjusting optical properties of a liquid crystal display (LCD), improving light utilization efficiency, or ensuring anti-reflectivity and visibility in an organic light emitting device (OLED), or even for AVA/R applications. Accordingly, the invention relates further to the use of such optical components for optical, electro-optical, decorative or security applications and to corresponding devices as such.
  • LCD liquid crystal display
  • OLED organic light emitting device
  • OLED displays are constructed with a metallic cathode which has high reflectivity and acts like a mirror. It is important that the viewer only sees the light emitted by the OLED and not light incident reflected off the display. To achieve this an anti-reflection layer or anti reflection stack is required in the display.
  • a circular polariser will be employed to optically isolate incident light and remove reflection.
  • the circular polariser consists of a linear polariser combined with a quarter wave retarder.
  • the quarter wave plate QWP must have an optical retardation that matches exactly one quarter of the wavelength of the incident light.
  • the QWP should be achromatic, so it performs equally well for all visible wavelengths.
  • the ambient contrast ratio ACR is an important figure of merit for OLED devices which may need to be viewed in bright sunlight.
  • Standard quarter wave plate materials have positive dispersion characteristics, i.e. the birefringence decreases with increasing wavelength. These positive dispersion QWP films have good anti-reflection performance only at a single wavelength (typically 550nm). Higher-end QWP films have negative dispersion (ND) characteristics, i.e. the birefringence increases with increasing wavelength.
  • ND negative dispersion
  • a negative dispersion film typically shows a quarter wave retardance at a wider wavelength range to a positive dispersion film, this leads to an achromatic antireflection performance.
  • Standard transparent materials have positive optical dispersion, the refractive index reduces with increasing wavelength.
  • An RM film with standard optical dispersion produces a QWP which converts linearly polarised input light to perfectly circular polarised light, and vice versa, for only a single wavelength. All other wavelengths will be converted to a nonideal elliptical polarisation state, a portion of this light will not be absorbed by the polariser after reflection and be transmitted to the viewer. This results in poor anti-reflection and a screen which may look purple rather than black.
  • the retarder To produce an achromatic QWP the retarder must have reverse (also known as negative) optical dispersion, the refractive index increases with increasing wavelength.
  • reverse optical dispersion QWP One way to make a reverse optical dispersion QWP is to combine a half wave plate (HWP) with positive optical dispersion with a QWP with positive optical dispersion. These two retarders must be laminated with their directors perpendicular to each other. The problem with this solution is increased process cost from having to coat two separate films and then laminate them together. There is also reduced yield due to the lamination cutting process.
  • Suitable optical films for this purpose are typically based on polymerisable liquid crystal materials, typically exhibiting a wavelength dependent retardation.
  • three main kind of optical behaviour are known: i) “Normal” or “Positive” optical dispersion, such as for example described in EP 0 940 707 B1 ii) “Reverse” or “Negative” optical dispersion, such as, for example described in WO 2016/020035 A1 , and iii) “Flat” optical dispersion, such as for example described in WO 2009/058396 A1 .
  • flat or negative dispersion polymerisable liquid crystal materials can be produced by adding at least one component with an ordinary refractive index (n 0 ) higher than extraordinary refractive index (n e ) in the formulation. Therefore, highly conjugated substituents are required in the orthogonal position with respect to the long-axis of the molecules.
  • the latter materials absorb part of the UV dose when curing optical films which results in poor degree of cure and poor thermal durability of cured films.
  • molecular blocks can easily oxidise under high temperatures in the presence of oxygen. Same applies to high birefringent formulations containing highly conjugated reactive mesogens which reduces the thermal durability of cured films and which are typically prone to yellowing.
  • WO 2008/1 19427 A1 describes a birefringent polymer film with negative optical dispersion, which is obtainable from a polymerisable LC medium comprising as negative dispersion component compounds having the H shape.
  • Suitable materials having a T-Shape and corresponding birefringent polymer films with negative optical dispersion are disclosed e.g. in US 2015175564, WO 17079867 A1 , WO16104317 A, US 2015277007 A1 , or WO 16171041 A1 and in particular include compounds represented by formulae 1 to 5 of US 2015175564 A1 , compounds represented by formulae (1-1) to (I-5), (I-8), (1-14), (1-16) to (I-36), (1-41), (I-54) to (I-65), (I-75) to (I-80), (I-82), (I-83), (I-86) to (I-97) and (1-121) to (1-125) of WO 17/079867 A1 , compounds represented by formulae (A12-16) to (A12-18), (A14-1) to (A14-3) and (A141 -1) to (A143-2) of WO 16104317 A1 , compounds represented by formulae (2-A
  • the bulky nature of the negative dispersion compounds according to the prior art are typically hard to align or give formulations with a narrow process window for annealing temperature, which is not convenient for mass production.
  • the polymer film is normally weaker and less resistant to heat.
  • the main disadvantage is that the cost of synthesis of the T-shape and H-shape materials is much higher than standard LC molecules due the increased number of synthesis steps.
  • a cheaper alternative to the typical reverse dispersion films would allow competitiveness in a wider range of markets particularly for OLED TV. Ravi K. Komanduri, Kristopher F. Lawler, and Michael J. Escuti (14 January 2013 / Vol. 21 , No.
  • Multi-Twist Retarders which are liquid crystal polymer films with chiral additives used to give them ideal optical properties over a range of bandwidths.
  • MTRs Multi-Twist Retarders
  • US 9,298,041 B discloses a multi-layer twisted retarder arrangement that includes two or three twisted layers configured to provide broadband retardance for a wide field of view, for example, by varying the number of layers, twist angles, and/or thickness of each layer.
  • the inventors of the present invention have found that one or more, preferably all of the above requirements can be fufilled, preferably at the same time, by using a polymerisable LC medium according to claim 1 .
  • the invention relates to an optical component exhibiting a reverse or negative optical dispersion profile comprising two or more liquid crystalline polymer films, wherein the first utilized polymer film exhibits a uniform planar alignment of the polymerised LC molecules and the second polymer film adjacent to the first polymer film exhibits a cholesteric alignment of the polymerised LC molecules having a % pitch rotation through the film thickness of the second polymer film.
  • the invention further relates to a method of production for an optical component as described above and below.
  • the invention especially relates to the use of an optical component as described above and below, in an optical, electronic or electro optical device.
  • the invention further relates to an optical, electronic or electro optical component or device as such, comprising an optical component as described above and below.
  • Said devices include, without limitation, electro optical displays, such as OLED and LCDs, non-linear optic (NLO) devices, optical information storage devices, electronic devices, electroluminescent displays, organic photovoltaic (OPV) devices, lighting devices, sensor devices, electro photographic recording devices, organic memory devices or devices for AR/VR applications.
  • electro optical displays such as OLED and LCDs
  • NLO non-linear optic
  • OLED organic photovoltaic
  • OLED organic photovoltaic
  • polymer will be understood to mean a molecule that encompasses a backbone of one or more distinct types of repeating units (the smallest constitutional unit of the molecule) and is inclusive of the commonly known terms ‘‘oligomer’’, ‘‘copolymer’’, ‘‘homopolymer’’ and the like. Further, it will be understood that the term polymer is inclusive of, in addition to the polymer itself, residues from initiators, catalysts, and other elements attendant to the synthesis of such a polymer, where such residues are understood as not being covalently incorporated thereto. Further, such residues and other elements, while normally removed during post polymerisation purification processes, are typically mixed or co-mingled with the polymer such that they generally remain with the polymer when it is transferred between vessels or between solvents or dispersion media.
  • (meth)acrylic polymer includes a polymer obtained from acrylic monomers, a polymer obtainable from methacrylic monomers, and a corresponding co-polymer obtainable from mixtures of such monomers.
  • polymerisation means the chemical process to form a polymer by bonding together multiple polymerisable groups or polymer precursors (polymerisable compounds) containing such polymerisable groups.
  • film and layer include rigid or flexible, self-supporting or freestanding films with mechanical stability, as well as coatings or layers on a supporting substrate or between two substrates.
  • liquid crystal or mesogenic compound means a compound comprising one or more calamitic (rod- or board/lath-shaped) or discotic (disk-shaped) mesogenic groups.
  • mesogenic group means a group with the ability to induce liquid crystal (LC) phase behaviour.
  • the compounds comprising mesogenic groups do not necessarily have to exhibit an LC phase themselves. It is also possible that they show LC phase behaviour only in mixtures with other compounds, or when the mesogenic compounds or materials, or the mixtures thereof, are polymerised.
  • the term “liquid crystal” is used hereinafter for both mesogenic and LC materials.
  • a calamitic mesogenic group is usually comprising a mesogenic core consisting of one or more aromatic or non-aromatic cyclic groups connected to each other directly or via linkage groups, optionally comprising terminal groups attached to the ends of the mesogenic core, and optionally comprising one or more lateral groups attached to the long side of the mesogenic core, wherein these terminal and lateral groups are usually selected e.g. from carbyl or hydrocarbyl groups, polar groups like halogen, nitro, hydroxy, etc., or polymerisable groups.
  • RM reactive mesogen
  • Non-mesogenic compound or material means a compound or material that does not contain a mesogenic group as defined above.
  • Visible light is electromagnetic radiation that has a wavelength in a range from about 400 nm to about 740 nm.
  • Ultraviolet (UV) light is electromagnetic radiation with a wavelength in a range from about 200 nm to about 450 nm.
  • linearly polarised light means light, which is at least partially linearly polarized.
  • the aligning light is linearly polarized with a degree of polarization of more than 5:1 .
  • Wavelengths, intensity and energy of the linearly polarised light are chosen depending on the photosensitivity of the photoalignable material. Typically, the wavelengths are in the UV-A, UV-B and/or UV-C range or in the visible range.
  • the linearly polarised light comprises light of wavelengths less than 450 nm, more preferably less than 420 nm at the same time the linearly polarised light preferably comprises light of wavelengths longer than 280nm, preferably more than 320nm, more preferably over 350nm.
  • the Irradiance (E e ) or radiation power is defined as the power of electromagnetic radiation (dO) per unit area (dA) incident on a surface:
  • the radiant exposure or radiation dose (He), is as the irradiance or radiation power (E e ) per time (t):
  • ‘clearing point” means the temperature at which the transition between the mesophase with the highest temperature range and the isotropic phase occurs.
  • “Polarizability” means the ease with which the electron distribution in the atom or molecule can be distorted.
  • the polarizability increases with greater number of electrons and a more diffuse electron cloud.
  • the polarizability can be calculated using a method described in e.g. Jap. J. Appl. Phys. 42, (2003) p. 3463.
  • optical retardation at a given wavelength R(/.) (in nm) of a layer of liquid crystalline or birefringent material is defined as the product of birefringence at that wavelength An( ) and layer thickness d (in nm) according to the equation
  • optical retardation R represents the difference in the optical path lengths in nanometres travelled by S- polarised and P-polarised light whilst passing through the birefringent material.
  • On-axis retardation means the retardation at normal incidence to the sample surface.
  • negative (optical) dispersion refers to a birefringent or liquid crystalline material or layer that exhibits reverse birefringence dispersion where the magnitude of the birefringence (An) increases with increasing wavelength ( ). i . e . , I An(450) I ⁇ I An(550) I , or An(450)/An(550) ⁇ 1 , where An(450) and An(550) are the birefringence of the material measured at wavelengths of 450nm and 550nm respectively.
  • positive (optical) dispersion” means a material or layer having I An(450) I > I An(550) I or An(450)/An(550) > 1 .
  • the optical dispersion can be expressed either as the "birefringence dispersion" by the ratio An(450)/An(550), or as “retardation dispersion” by the ratio R(450)/R(550), wherein R(450) and R(550) are the retardation of the material measured at wavelengths of 450nm and 550nm respectively. Since the layer thickness d does not change with the wavelength, R(450)/R(550) is equal to An(450)/An(550).
  • a material or layer with negative or reverse dispersion has R(450)/R(550) ⁇ 1 or I R(450) I ⁇ I R(550) I
  • a material or layer with positive or normal dispersion has R(450)/R(550) > 1 or
  • optical dispersion means the retardation dispersion i.e. , the ratio R(450)/R(550).
  • high dispersion means that the absolute value of the dispersion shows a large deviation from 1
  • low dispersion means that the absolute value of the dispersion shows a small deviation from 1
  • high negative dispersion means that the dispersion value is significantly smaller than 1
  • low negative dispersion means that the dispersion value is only slightly smaller than 1 .
  • the retardation (R(/.)) of a material can be measured using a spectroscopic ellipsometer, for example the M2000 spectroscopic ellipsometer manufactured by J. A. Woollam Co. This instrument can measure the optical retardance in nanometres of a birefringent sample e.g., Quartz over a range of wavelengths typically, 370nm to 2000nm. From this data it is possible to calculate the dispersion (R(450)/R(550) or An(450)/An(550)) of a material.
  • the birefringence An is defined as follows
  • n e the extraordinary refractive index and n 0 is the ordinary refractive index
  • n av the effective average refractive index
  • the average refractive index n av and the ordinary refractive index n 0 can be measured using an Abbe refractometer. An can then be calculated from the above equations.
  • a polymerizable LC medium in accordance with the present invention can be prepared, for example, by doping the medium with chiral compounds having a high twisting power.
  • HTPtotai Zi Ci HTPi wherein ci is the concentration of each individual chiral compound and HTPi is the helical twisting power of each individual chiral compound.
  • IHTPA I (Is Cs HTPs) - ((ZrCrHTPr) wherein c s is the concentration of each individual chiral compound with S configuration, HTPs is the helical twisting power of each individual chiral compound having S configuration and wherein c r is the concentration of each individual chiral compound with R configuartion and HTPR is the helical twisting power of each individual chiral compound having R configuration.
  • director is known in prior art and means the preferred orientation direction of the long molecular axes (in case of calamitic compounds) or short molecular axes (in case of discotic compounds) of the liquidcrystalline or RM molecules. In case of uniaxial ordering of such anisotropic molecules, the director is the axis of anisotropy. All physical properties have been and are determined according to "Merck Liquid Crystals, Physical Properties of Liquid Crystals", Status Nov. 1997, Merck KGaA, Germany and are given for a temperature of 20 °C, unless explicitly stated otherwise.
  • the optical anisotropy (An) is determined at a wavelength of 589.3 nm
  • “Hydrocarbyl group” denotes a carbyl group, which additionally contains one or more H atoms and optionally one or more heteroatoms, such as, for example, N, O, S, P, Si, Se, As, Te or Ge.
  • a carbyl or hydrocarbyl group can be a saturated or unsaturated group. Unsaturated groups are, for example, aryl, alkenyl, or alkynyl groups.
  • a carbyl or hydrocarbyl group having more than 3 C atoms can be straight chain, branched and/or cyclic and may contain spiro links or condensed rings.
  • Preferred carbyl and hydrocarbyl groups are optionally substituted alkyl, alkenyl, alkinyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy and alkoxycarbonyloxy having 1 to 40, preferably 1 to 25, particularly preferably 1 to 18 C atoms, optionally substituted aryl or aryloxy having 6 to 40, preferably 6 to 25 C atoms, or optionally substituted alkylaryl, arylalkyl, alkylaryloxy, arylalkyloxy, arylcarbonyl, aryloxycarbonyl, arylcarbonyloxy and aryloxycarbonyloxy having 6 to 40, preferably 6 to 25 C atoms.
  • carbyl and hydrocarbyl groups are C1-C40 alkyl, C2-C40 alkenyl, C2-C40 alkinyl, C3-C40 allyl, C4-C40 alkyldienyl, C4-C40 polyenyl, C6-C40 aryl, C6-C40 alkylaryl, C6-C40 arylalkyl, C6-C40 alkylaryloxy, C6-C40 arylalkyloxy, C2-C40 heteroaryl, C4-C40 cycloalkyl, C4-C40 cycloalkenyl, etc.
  • C1-C22 alkyl Preference is given to C1-C22 alkyl, C2-C22 alkenyl, C2-C22 alkinyl, C3-C22 allyl, C4-C22 alkyldienyl, C6-C12 aryl, C6-C20 arylalkyl, and C2-C20 heteroaryl.
  • R x preferably denotes H, halogen, a straight-chain, branched or cyclic alkyl chain having 1 to 25 C atoms, in which, in addition, one or more non-adjacent C atoms may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, and in which one or more H atoms may be replaced by fluorine, an optionally substituted aryl or aryloxy group having 6 to 40 C atoms or an optionally substituted heteroaryl or heteroaryloxy group having 2 to 40 C atoms.
  • Preferred alkyl groups are, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl, n-hexyl, 2-ethylhexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, dodecanyl, trifluoromethyl, perfluoro-n-butyl, 2,2,2-trifluoroethyl, perfluorooctyl, perfluorohexyl, etc.
  • Preferred alkenyl groups are, for example, ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, etc.
  • Preferred alkinyl groups are, for example, ethynyl, propynyl, butynyl, pentynyl, hexynyl, octynyl, etc.
  • Preferred alkoxy groups are, for example, methoxy, ethoxy, 2- meth oxy ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, 2-methylbutoxy, n-pentoxy, n-hexoxy, n-heptyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, n-undecyloxy, n-dodecyloxy, etc.
  • Preferred amino groups are, for example, dimethylamino, methylamino, methylphenylamino, phenylamino, etc.
  • Aryl and heteroaryl groups can be monocyclic or polycyclic, i.e. they can have one ring (such as, for example, phenyl) or two or more rings, which may also be fused (such as, for example, naphthyl) or covalently linked (such as, for example, biphenyl), or contain a combination of fused and linked rings.
  • Heteroaryl groups contain one or more heteroatoms, preferably selected from O, N, S and Se.
  • Preferred aryl groups are, for example, phenyl, biphenyl, terphenyl, [1 ,1 ':3 l ,1"]terphenyl-2 l -yl, naphthyl, anthracene, binaphthyl, phenanthrene, pyrene, dihydropyrene, chrysene, perylene, tetracene, pentacene, benzopyrene, fluorene, indene, indenofluorene, spirobifluorene, etc.
  • Preferred heteroaryl groups are, for example, 5-membered rings, such as pyrrole, pyrazole, imidazole, 1 ,2,3- triazole, 1 ,2,4-triazole, tetrazole, furan, thiophene, selenophene, oxazole, isoxazole, 1 ,2-thiazole, 1 ,3-thiazole, 1 ,2,3-oxadiazole, 1 ,2,4-oxadiazole, 1 ,2,5-oxadiazole, 1 ,3,4-oxadiazole, 1 ,2,3-thiadiazole, 1 ,2,4-thiadiazole,
  • the (non-aromatic) alicyclic and heterocyclic groups encompass both saturated rings, i.e. those that contain exclusively single bonds, and partially unsaturated rings, i.e. those that may also contain multiple bonds.
  • Heterocyclic rings contain one or more heteroatoms, preferably selected from Si, O, N, S and Se.
  • the (non-aromatic) alicyclic and heterocyclic groups can be monocyclic, i.e. contain only one ring (such as, for example, cyclohexane), or polycyclic, i.e. contain a plurality of rings (such as, for example, decahydronaphthalene or bicyclooctane).
  • Preference is given to saturated groups.
  • Preference is furthermore given to mono-, bi-, or tricyclic groups having 3 to 25 C atoms, which optionally contain fused rings and which are optionally substituted.
  • Preferred alicyclic and heterocyclic groups are, for example, 5-membered groups, such as cyclopentane, tetrahydrofuran, tetrahydrothiofuran, pyrrolidine, 6-membered groups, such as cyclohexane, silinane, cyclohexene, tetrahydropyran, tetrahydrothiopyran, 1 ,3-dioxane, 1 ,3-dithiane, piperidine, 7-membered groups, such as cycloheptane, and fused groups, such as tetrahydronaphthalene, decahydronaphthalene, indane, bicyclo[1 .1 .1 ]pentane-1 ,3-diyl, bicyclo[2.2.2]octane-1 ,4-diyl, spiro[3.3]heptane-2,6-diyl, octahydr
  • the aryl, heteroaryl, (non-aromatic) alicyclic and heterocyclic groups optionally have one or more substituents, which are preferably selected from the group comprising silyl, sulfo, sulfonyl, formyl, amine, imine, nitrile, mercapto, nitro, halogen, C1-C12 alkyl, C6-C12 aryl, C1-C12 alkoxy, hydroxyl, or combinations of these groups.
  • Preferred substituents are, for example, solubility-promoting groups, such as alkyl or alkoxy, electronwithdrawing groups, such as fluorine, nitro or nitrile, or substituents for increasing the glass transition temperature (Tg) in the polymer, in particular bulky groups, such as, for example, t-butyl or optionally substituted aryl groups.
  • Substituted silyl or aryl preferably means substituted by halogen, -CN, R y , -OR*, -CO-R y , -CO-O-R y , -O-CO- R y or -O-CO-O-R y , in which R y denotes H, a straight-chain, branched or cyclic alkyl chain having 1 to 12 C atoms.
  • Halogen denotes F, Cl, Br or I, preferably F or Cl, more preferably F.
  • polymerisable groups (P) are selected from the group consisting of
  • W 1 denotes H, F, Cl, CN, CF 3 , phenyl or alkyl having 1 to 5 C atoms, in particular H, F, Cl or CH 3 ,
  • W 2 denotes H or alkyl having 1 to 5 C atoms, in particular H, methyl, ethyl, or n-propyl,
  • W 3 and W 4 each, independently of one another, denote H, Cl or alkyl having 1 to 5 C atoms
  • Phe denotes 1 ,4-phenylene, which is optionally substituted by one or more radicals L as being defined above but being different from P-Sp
  • preferably preferred substituents L are F, Cl, CN, NO 2 , CH3, C2H5, OCH3, OC2H5, COCH3, COC2H5, COOCH3, COOC2H5, CF3, OCF3, OCHF2, OC2F5, furthermore phenyl, and ki , k 2 and ks each, independently of one another, denote 0 or 1 , ks preferably denotes 1 , and k4 is an integer from 1 to 10.
  • polymerizable groups (P) are vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxide, most preferably acrylate or methacrylate, in particular acrylate.
  • all multireactive polymerisable compounds and sub-formulae thereof contain instead of one or more radicals P-Sp-, one or more branched radicals containing two or more polymerisable groups P (multireactive polymerisable radicals).
  • X has one of the meanings indicated for X 1 .
  • P v to P z each, independently of one another, have one of the meanings indicated above for P.
  • Preferred spacer groups Sp are selected from the formula Sp'-X 1 , so that the radical "P-Sp-" conforms to the formula "P-Sp'-X 1 -", where
  • X' denotes -O-, -S-, -CO-, -COO-, -OCO-, -O-COO-, -CO-NR"-,
  • R xx and R yy each, independently of one another, denote H or alkyl having 1 to 12 C atoms, and
  • Y xx and Y yy each, independently of one another, denote H, F, Cl or CN.
  • X' is preferably -O-, -S- -CO-, -COO-, -OCO-, -O-COO-,
  • Typical spacer groups Sp 1 are, for example, -(CH2)pi-, -(CH2CH2O) q i-CH2CH2-, -CH2CH2-S-CH2CH2-, - CH2CH2-NH-CH2CH2- or -(SIR xx R yy -O) P i-, in which p1 is an integer from 1 to 12, q1 is an integer from 1 to 3, and R ⁇ and R yy have the above-mentioned meanings.
  • Particularly preferred groups -X'-Sp 1 - are -(CH2)pi-, -O-(CH2) P I-, -OCO-(CH2) P I-, -OCOO-(CH2) P I-, in which p1 is an integer from 1 to 12.
  • Particularly preferred groups Sp 1 are, for example, in each case straight-chain, methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, octadecylene, ethyleneoxyethylene, methyleneoxybutylene, ethylenethioethylene, ethylene-N- methyliminoethylene, 1 -methylalkylene, ethenylene, propenylene and butenylene.
  • trans-1 ,4-cyclohexylene denotes trans-1 ,4-cyclohexylene, and denote 1 ,4-phenylene.
  • one or more of the liquid crystalline polymer films of the optical component is obtainable or obtained from a polymerizable LC medium comprising one or more di- or multireactive RMs which are preferably selected from the group of compounds of formula DRM,
  • P 1 and P 2 independently of each other denote a polymerisable group
  • Sp 1 and Sp 2 independently of each other are a spacer group or a single bond
  • MG is a rod-shaped mesogenic group, which is preferably selected of formula MG
  • a 1 and A 2 denote, in case of multiple occurrence independently of one another, an aromatic or alicyclic group, which optionally contains one or more heteroatoms selected from N, O and S, and is optionally mono- or polysubstituted by L,
  • R x and R y independently of each other denote H or alkyl with 1 to 12 C-atoms
  • Y 1 and Y 2 independently of each other denote H, F, Cl or CN, n is 1 , 2, 3 or 4, preferably 1 or 2, most preferably 2, n1 is an integer from 1 to 10, preferably 1 , 2, 3 or 4.
  • Preferred groups A 1 and A 2 include, without limitation, furan, pyrrol, thiophene, oxazole, thiazole, thiadiazole, imidazole, phenylene, cyclohexylene, bicyclooctylene, cyclohexenylene, pyridine, pyrimidine, pyrazine, azulene, indane, fluorene, naphthalene, tetrahydronaphthalene, anthracene, phenanthrene and dithienothiophene, all of which are unsubstituted or substituted by 1 , 2, 3 or 4 groups L as defined above.
  • Particular preferred groups A 1 and A 2 are selected from 1 ,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, thiophene-2, 5-diyl, naphthalene-2,6-diyl, 1 ,2,3,4-tetrahydro-naphthalene-2,6-diyl, indane-2,5-diyl, bicyclooctylene or 1 ,4-cyclohexylene wherein one or two non-adjacent CH2 groups are optionally replaced by O and/or S, wherein these groups are unsubstituted or substituted by 1 , 2, 3 or 4 groups L as defined above.
  • Preferred RMs of formula DRM are selected of formula DRMa
  • P° is, in case of multiple occurrence independently of one another, a polymerisable group, preferably an acryl, methacryl, oxetane, epoxy, vinyl, heptadiene, vinyloxy, propenyl ether or styrene group,
  • L has on each occurrence identically or differently one of the meanings given for L 1 in formula I, and is preferably, in case of multiple occurrence independently of one another, selected from F, Cl, CN or optionally halogenated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 5 C atoms, r is 0, 1 , 2, 3 or 4, x and y are independently of each other 0 or identical or different integers from 1 to 12, z is 0 or 1 , with z being 0 if the adjacent x or y is 0.
  • Very preferred RMs of formula DRM are selected from the following formulae: wherein P°, L, r, x, y and z are as defined in formula DRMa.
  • the concentration of di- or multireactive RMs, preferably those of formula DRM and its subformulae, in the polymerizable LC medium is preferably from 1 % to 60 %, very preferably from 10 to 60%, more preferably 20 to 55%.
  • the polymerizable LC medium comprises one or more monoreactive RMs additionally to the di- or multireactive RMs that are preferably selected of formula DRM
  • X is halogen, preferably F or Cl, and
  • R x and R y are independently of each other H or alkyl with 1 to 12 C-atoms.
  • the RMs of formula MRM are selected from the following formulae. MRM24 wherein P°, L, r, x, y and z are as defined in formula DRMa,
  • R° is alkyl, alkoxy, thioalkyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 or more, preferably 1 to 15 C atoms or denotes Y° or P-(CH2) y -(O) z -, -OCH2-, -CH2O-, -
  • Y° is F, Cl, CN, NO2, OCH3, OCN, SCN, SFs, or mono- oligo- or polyfluorinated alkyl or alkoxy with 1 to 4 C atoms,
  • a 0 is, in case of multiple occurrence independently of one another, 1 ,4-phenylene that is unsubstituted or substituted with 1 , 2, 3 or 4 groups L, or trans-1 ,4-cyclohexylene,
  • R 01 02 are independently of each other H, R° or Y°, u and v are independently of each other 0, 1 or 2, w is 0 or 1 , and wherein the benzene and naphthalene rings can additionally be substituted with one or more identical or different groups L.
  • MRM1 Especially preferred are compounds of formula MRM1 , MRM2, MRM3, MRM4, MRM5, MRM6, MRM7, in particular those of formula MRM1 , MRM4, MRM6, and MRM7.
  • the concentration of all monoreactive RMs in the polymerizable LC medium is preferably from 1 to 80%, very preferably from 5 to 70%, more preferably 10 to 60%.
  • the proportion of polymerizable mesogenic compounds in the polymerizable liquid-crystalline medium according to the present invention as a whole is in the range from 30 to 99 % by weight, more preferably in the range from 40 to 97 % by weight and even more preferably in the range from 50 to 95% by weight.
  • the proportion of said mono-, di- or multireactive liquid-crystalline compounds is preferably in the range from 30 to 99.9 % by weight, more preferably in the range from 40 to 99.9 % by weight and even more preferably in the range from 50 to 99.9% by weight.
  • the proportion of di- or multireactive polymerizable mesogenic compounds in the polymerizable liquid-crystalline medium according to the present invention as a whole is preferably in the range from 5 to 99 % by weight, more preferably in the range from 10 to 97 % by weight and even more preferably in the range from 15 to 95% by weight.
  • the proportion of monoreactive polymerizable mesogenic compounds in a polymerizable liquid-crystalline medium according to the present invention as a whole is, if present, preferably in the range from 5 to 80% by weight, more preferably in the range from 10 to 75 % by weight and even more preferably in the range from 15 to 70 % by weight.
  • the proportion of multireactive polymerizable mesogenic compounds in a polymerizable liquid-crystalline medium according to the present invention as a whole is, if present, preferably in the range from 1 to 30 % by weight, more preferably in the range from 2 to 20 % by weight and even more preferably in the range from 3 to 10% by weight.
  • the polymerizable LC medium does not contain polymerizable mesogenic compounds having more than two polymerizable groups.
  • the polymerizable LC medium does not contain polymerizable mesogenic compounds having less than two polymerizable groups.
  • the polymerizable LC materia comprises one or more monoreactive mesogenic compounds, preferably selected from formulae MRM-10, one or more direactive mesogenic compounds, preferably selected from formula DRMa-1 .
  • the polymerizable LC medium comprises at least two monoreactive mesogenic compounds, preferably selected from compounds of formulae MRM-8 and/or MRM-10, one or more direactive mesogenic compounds, preferably selected from formula DRMa-1 .
  • the polymerizable LC medium comprises at least two monoreactive mesogenic compounds, preferably selected from compounds of formulae MRM-8 and/or MRM-10, at least two direactive mesogenic compounds, preferably selected from compounds of formula DRMa-1 .
  • the polymerizable LC medium comprises at least two direactive mesogenic compounds, preferably selected from compounds of formula DRMa-1 .
  • the polymerizable LC medium suitable for the production of the second or cholesteric polymer film comprises one or more chiral compounds.
  • the utilized chiral compounds have each alone or in combination with each other an absolute value of the helical twisting power (HTP) of 20 pm' 1 or more, preferably of 40 pm' 1 or more, more preferably in the range of 60 pm' 1 or more, most preferably in the range of 80 pm' 1 or more to 260 pm' 1 .
  • HTP helical twisting power
  • non-polymerisable chiral compounds are selected from the group of compounds of formulae C-l to C-lll, the latter ones including the respective (S,S) enantiomers, wherein E and F are each independently 1 ,4-phenylene or trans-1 ,4-cyclohexylene, v is 0 or 1 , Z° is -COO-, - OCO-, -CH2CH2- or a single bond, and R is alkyl, alkoxy or alkanoyl with 1 to 12 C atoms.
  • chiral compounds which do not necessarily have to show a liquid crystalline phase.
  • the compounds of formula C-ll and their synthesis are described in WO 98/00428. Especially preferred is the compound CD-1 , as shown in table D below.
  • the compounds of formula C-lll and their synthesis are described in GB 2 328 207.
  • typically used chiral compounds are e.g. the commercially available R/S-5011 , CD-1 , R/S-811 and CB-15 (from Merck KGaA, Darmstadt, Germany).
  • the polymerizable LC medium preferably comprises 1 to 5, in particular 1 to 3, very preferably 1 or 2 chiral compounds, preferably selected from the above formula C-ll, in particular CD-1 , and/or formula C-lll and/or R-5011 or S-5011 , very preferably, the chiral compound is R-5011 , S-5011 or CD-1 .
  • the polymerizable LC medium comprise one or more non-reactive chiral compound and/or one or more reactive chiral compounds, which are preferably selected from mono- and/or multireactive chiral compounds.
  • Suitable mesogenic reactive chiral compounds preferably comprise one or more ring elements, linked together by a direct bond or via a linking group and, where two of these ring elements optionally may be linked to each other, either directly or via a linking group, which may be identical to or different from the linking group mentioned.
  • the ring elements are preferably selected from the group of four-, five-, six- or seven-, preferably of five- or six-, membered rings.
  • Preferred mono-reactive chiral compounds are selected from compounds of formula CRMa to CRMc. b c wherein
  • P°* denotes a polymerisable group
  • R is alkyl, alkoxy, thioalkyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 or more, preferably 1 to 15 C atoms or P°*-(CH2)o-X 2 -,
  • a 0 and B° are, in case of multiple occurrence independently of one another, 1 ,4-phenylene that is unsubstituted or substituted with 1 , 2, 3 or 4 groups L as defined above, or trans-1 ,4-cyclohexylene,
  • X 1 and X 2 are independently of each other -O-, -COO-, -OCO-, -O-CO-O- or a single bond,
  • Z°* and Z° are, in case of multiple occurrence independently of one another, -COO-, -OCO-, -O-CO-O-,
  • 0 is, independently of each other 0, 1 , 2 or 3, t is 0, 1 or 2,
  • naphthalene rings can additionally be substituted with one or more identical or different groups L wherein L is, independently of each other F, Cl, CN, halogenated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 5 C atoms.
  • the compounds of formula CRM are preferably selected from the group of compounds of the following formula wherein A 0 , B°, Z 0 *, P 0 *, a and b have the meanings given in formula CRM or one of the preferred meanings given above and below, and (OCO) denotes -O-CO- or a single bond, and X2 denotes -O-, -COO-, -OCO-, -O-CO-O- or a single bond.
  • Especially preferred compounds of formula CRM are selected from the group consisting of the following subformulae: wherein R is -X 2 -(CH2)x-P°* as defined in formula CRMa, and the benzene and naphthalene rings are unsubstituted or substituted with 1 , 2, 3 or 4 groups L as defined above and below.
  • the polymerizable LC medium optionally comprises one or more additives selected from the group consisting of further polymerization initiators, antioxidants, surfactants, stabilisers, catalysts, sensitizers, inhibitors, chain-transfer agents, co-reacting monomers, reactive thinners, surfaceactive compounds, lubricating agents, wetting agents, dispersing agents, hydrophobing agents, adhesive agents, flow improvers, degassing or defoaming agents, deaerators, diluents, reactive diluents, auxiliaries, colourants, dyes, pigments and nanoparticles.
  • additives selected from the group consisting of further polymerization initiators, antioxidants, surfactants, stabilisers, catalysts, sensitizers, inhibitors, chain-transfer agents, co-reacting monomers, reactive thinners, surfaceactive compounds, lubricating agents, wetting agents, dispersing agents, hydrophobing agents, adhesive agents, flow improvers, degassing or defoaming
  • the polymerizable LC medium optionally comprises one or more additives selected from polymerizable non-mesogenic compounds (reactive thinners).
  • the amount of these additives in the polymerizable LC medium is preferably from 0 to 30 %, very preferably from 0 to 25 %.
  • the reactive thinners used are not only substances which are referred to in the actual sense as reactive thinners, but also auxiliary compounds already mentioned above which contain one or more complementary reactive units or polymerizable groups P, for example hydroxyl, thiol-, or amino groups, via which a reaction with the polymerizable units of the liquid-crystalline compounds can take place.
  • the substances which are usually capable of photopolymerization, include, for example, mono-, bi- and polyfunctional compounds containing at least one olefinic double bond.
  • examples thereof are vinyl esters of carboxylic acids, for example of lauric, myristic, palmitic and stearic acid, and of dicarboxylic acids, for example of succinic acid, adipic acid, allyl and vinyl ethers and methacrylic and acrylic esters of monofunctional alcohols, for example of lauryl, myristyl, palmityl and stearyl alcohol, and diallyl and divinyl ethers of bifunctional alcohols, for example ethylene glycol and 1 ,4-butanediol.
  • methacrylic and acrylic esters of polyfunctional alcohols are also suitable, for example, methacrylic and acrylic esters of polyfunctional alcohols, in particular those which contain no further functional groups, or at most ether groups, besides the hydroxyl groups.
  • examples of such alcohols are bifunctional alcohols, such as ethylene glycol, propylene glycol and their more highly condensed representatives, for example diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol etc., butanediol, pentanediol, hexanediol, neopentyl glycol, alkoxylated phenolic compounds, such as ethoxylated and propoxylated bisphenols, cyclohexanedimethanol, trifunctional and polyfunctional alcohols, such as glycerol, trimethylolpropane, butanetriol, trimethylolethane, pentaerythritol, ditrimethylolpropane, dipenta
  • polyester (meth)acrylates which are the (meth)acrylic ester of polyesterols.
  • polyesterols examples are those which can be prepared by esterification of polycarboxylic acids, preferably dicarboxylic acids, using polyols, preferably diols.
  • the starting materials for such hydroxylcontaining polyesters are known to the person skilled in the art.
  • Dicarboxylic acids which can be employed are succinic, glutaric acid, adipic acid, sebacic acid, o-phthalic acid and isomers and hydrogenation products thereof, and esterifiable and transesterifiable derivatives of said acids, for example anhydrides and dialkyl esters.
  • Suitable polyols are the abovementioned alcohols, preferably ethyleneglycol, 1 ,2- and 1 ,3-propylene glycol, 1 ,4-butanediol, 1 ,6-hexanediol, neopentyl glycol, cyclohexanedimethanol and polyglycols of the ethylene glycol and propylene glycol type.
  • Suitable reactive thinners are furthermore 1 ,4-divinylbenzene, triallyl cyanurate, acrylic esters of tricyclodecenyl alcohol also known under the name dihydrodicyclopentadienyl acrylate, and the allyl esters of acrylic acid, methacrylic acid and cyanoacrylic acid.
  • This group includes, for example, dihydric and polyhydric alcohols, for example ethylene glycol, propylene glycol and more highly condensed representatives thereof, for example diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol etc., butanediol, pentanediol, hexanediol, neopentyl glycol, cyclohexanedimethanol, glycerol, trimethylolpropane, butanetriol, trimethylolethane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, sorbitol, mannitol and the corresponding alkoxylated, in particular ethoxylated and propoxylated alcohols.
  • dihydric and polyhydric alcohols for example ethylene glycol, propylene glycol and more highly condensed representatives thereof, for example diethylene glycol, triethylene glycol, dipropylene
  • the group furthermore also includes, for example, alkoxylated phenolic compounds, for example ethoxylated and propoxylated bisphenols.
  • These reactive thinners may furthermore be, for example, epoxide or urethane (meth)acrylates.
  • Epoxide (meth)acrylates are, for example, those as obtainable by the reaction, known to the person skilled in the art, of epoxidized olefins or poly- or diglycidyl ether, such as bisphenol A diglycidyl ether, with (meth)acrylic acid.
  • Urethane (meth)acrylates are, in particular, the products of a reaction, likewise known to the person skilled in the art, of hydroxylalkyl (meth)acrylates with poly- or diisocyanates.
  • Such epoxide and urethane (meth)acrylates are included amongst the compounds listed above as “mixed forms”.
  • the low-crosslinking (high-crosslinking) liquid-crystalline compositions can be prepared, for example, using corresponding reactive thinners, which have a relatively low (high) number of reactive units per molecule.
  • the group of diluents include, for example:
  • C1-C4-alcohols for example methanol, ethanol, n-propanol, isopropanol, butanol, isobutanol, sec-butanol and, in particular, the C5-C12-alcohols n-pentanol, n-hexanol, n-heptanol, n-octanol, n-nonanol, n-decanol, n- undecanol and n-dodecanol, and isomers thereof, glycols, for example 1 ,2-ethylene glycol, 1 ,2- and 1 ,3- propylene glycol, 1 ,2-, 2,3- and 1 ,4-butylene glycol, di- and triethylene glycol and di- and tripropylene glycol, ethers, for example methyl tert-butyl ether, 1 ,2-ethylene glycol mono- and dimethyl ether, 1 ,2-ethylene glycol
  • these diluents can also be mixed with water.
  • suitable diluents are C1-C4-alcohols, for example methanol, ethanol, n-propanol, isopropanol, butanol, isobutanol and sec-butanol, glycols, for example 1 ,2-ethylene glycol, 1 ,2- and 1 ,3-propylene glycol, 1 ,2-, 2,3- and 1 ,4-butylene glycol, di- and triethylene glycol, and di- and tripropylene glycol, ethers, for example tetrahydrofuran and dioxane, ketones, for example acetone, methyl ethyl ketone and diacetone alcohol (4- hydroxy-4-methyl-2-pentanone), and C1-C4-alkyl esters, for example methyl, ethyl, propyl and butyl acetate.
  • C1-C4-alcohols for
  • the diluents are optionally employed in a proportion of from about 0 to 10.0% by weight, preferably from about 0 to 5.0% by weight, based on the total weight of the polymerizable LC medium.
  • the antifoams and deaerators (c1 )), lubricants and flow auxiliaries (c2)), thermally curing or radiation-curing auxiliaries (c3)), substrate wetting auxiliaries (c4)), wetting and dispersion auxiliaries (c5)), hydrophobicizing agents (c6)), adhesion promoters (c7)) and auxiliaries for promoting scratch resistance (c8)) cannot strictly be delimited from one another in their action.
  • lubricants and flow auxiliaries often also act as antifoams and/or deaerators and/or as auxiliaries for improving scratch resistance.
  • Radiation-curing auxiliaries can also act as lubricants and flow auxiliaries and/or deaerators and/or as substrate wetting auxiliaries. In individual cases, some of these auxiliaries can also fulfil the function of an adhesion promoter (c8)).
  • a certain additive can therefore be classified in a number of the groups c1) to c8) described below.
  • the antifoams in group c1) include silicon-free and silicon-containing polymers.
  • the silicon-containing polymers are, for example, unmodified or modified polydialkylsiloxanes or branched copolymers, comb or block copolymers comprising polydialkylsiloxane and polyether units, the latter being obtainable from ethylene oxide or propylene oxide.
  • the deaerators in group c1) include, for example, organic polymers, for example polyethers and polyacrylates, dialkylpolysiloxanes, in particular dimethylpolysiloxanes, organically modified polysiloxanes, for example arylalkyl-modified polysiloxanes, and fluorosilicones.
  • organic polymers for example polyethers and polyacrylates
  • dialkylpolysiloxanes in particular dimethylpolysiloxanes
  • organically modified polysiloxanes for example arylalkyl-modified polysiloxanes
  • fluorosilicones fluorosilicones.
  • the action of the antifoams is essentially based on preventing foam formation or destroying foam that has already formed.
  • Antifoams essentially work by promoting coalescence of finely divided gas or air bubbles to give larger bubbles in the medium to be deaerated, for example the compositions according to the invention, and thus accelerate escape of the gas (of the air). Since antifoams can frequently also be employed as deaerators and vice versa, these additives have been included together under group c1).
  • auxiliaries are, for example, commercially available from Tego as TEGO® Foamex 800, TEGO® Foamex 805 N, TEGO® Foamex 810, TEGO® Foamex 815 N, TEGO® Foamex 825, TEGO® Foamex 835, TEGO® Foamex 840, TEGO® Foamex 842, TEGO® Foamex 1435, TEGO® Foamex 1488, TEGO® Foamex 1495, TEGO® Foamex 3062, TEGO® Foamex 7447, TEGO® Foamex 8020, TEGO® Foamex 8030, TEGO® Foamex 8050, Tego® Foamex N, TEGO® Foamex K 3, TEGO® Antifoam 2-18, TEGO® Antifoam 2-18, TEGO® Antifoam 2-57, TEGO® Antifoam 2-80, TEGO® Antifoam 2-82, TEGO® Anti
  • the auxiliaries in group c1) are optionally employed in a proportion of from about 0 to 3.0% by weight, preferably from about 0 to 2.0% by weight, based on the total weight of the polymerizable LC medium.
  • the lubricants and flow auxiliaries typically include silicon-free, but also silicon-containing polymers, for example polyacrylates or modifiers, low-molecular-weight polydialkylsiloxanes.
  • the modification consists in some of the alkyl groups having been replaced by a wide variety of organic radicals. These organic radicals are, for example, polyethers, polyesters or even long-chain (fluorinated)alkyl radicals, the former being used the most frequently.
  • polyether radicals in the correspondingly modified polysiloxanes are usually built up from ethylene oxide and/or propylene oxide units. Generally, the higher the proportion of these alkylene oxide units in the modified polysiloxane, the more hydrophilic is the resultant product.
  • auxiliaries are, for example, commercially available from Tego as TEGO® Glide 100, TEGO® Glide ZG 400, TEGO® Glide 406, TEGO® Glide 410, TEGO® Glide 411 , TEGO® Glide 415, TEGO® Glide 420, TEGO® Glide 432, TEGO® Glide 435, TEGO® Glide 440, TEGO® Glide 450, TEGO® Glide 466, TEGO® Glide 490, TEGO® Glide 496, TEGO® Glide A116, TEGO® Glide A 115, TEGO® Glide B 1484 (can also be used as antifoam and deaerator), TEGO® Flow ATF2, TEGO® Flow 300, TEGO® Flow 460N, TEGO® Flow 425 and TEGO® Flow ZFS 460.
  • TEGO® Rad 2500 TEGO® Rad 2600, TEGO® Rad 2650, and TEGO® Rad 2700, which are likewise obtainable from TEGO.
  • Such-auxiliaries are also available, for example, from BYK as BYK®-300 BYK®-306, BYK®-307, BYK®-310, BYK®-320, BYK®-333, BYK®-341 , Byk® 354, Byk®361 , Byk®361 N, BYK®388.
  • Such-auxiliaries are also available, for example, from 3M as FC4430®.
  • Such-auxiliaries are also available, for example, from Cytonix as FluorN®561 or FluorN®562.
  • Such-auxiliaries are also available, for example, from Merck KGaA as Tivida® FL 2300 and Tivida® FL 2500
  • the auxiliaries in group c2) are optionally employed in a proportion of from about 0 to 3.0% by weight, preferably from about 0 to 2.0% by weight, based on the total weight of the polymerizable LC medium.
  • the radiation-curing auxiliaries include, in particular, polysiloxanes having terminal double bonds which are, for example, a constituent of an acrylate group.
  • Such auxiliaries can be crosslinked by actinic or, for example, electron radiation. These auxiliaries generally combine a number of properties together. In the uncrosslinked state, they can act as antifoams, deaerators, lubricants and flow auxiliaries and/or substrate wetting auxiliaries, while, in the crosslinked state, they increase, in particular, the scratch resistance, for example of coatings or films which can be produced using the compositions according to the invention.
  • Suitable radiation-curing auxiliaries are the products TEGO® Rad 2100, TEGO® Rad 2200, TEGO® Rad 2500, TEGO® Rad 2650 and TEGO® Rad 2700 available from TEGO and the product BYK®- 371 available from BYK.
  • Thermally curing auxiliaries in group c3) contain, for example, primary OH groups, which are able to react with isocyanate groups, for example of the binder.
  • thermally curing auxiliaries which can be used, are the products BYK®-370, BYK®-373 and BYK®-375 available from BYK.
  • the auxiliaries in group c3) are optionally employed in a proportion of from about 0 to 5.0% by weight, preferably from about 0 to 3.0% by weight, based on the total weight of the polymerizable LC medium.
  • the substrate wetting auxiliaries in group c4) serve, in particular, to increase the wettability of the substrate to be printed or coated, for example, by printing inks or coating compositions, for example compositions according to the invention.
  • the generally attendant improvement in the lubricant and flow behaviour of such printing inks or coating compositions has an effect on the appearance of the finished (for example crosslinked) print or coating.
  • auxiliaries are commercially available, for example from Tego as TEGO® Wet KL 245, TEGO® Wet 250, TEGO® Wet 260, TEGO® Wet 500, TEGO® Wet 505, TEGO® Wet 510, and from BYK as BYK®-306, BYK®-307, BYK®-310, BYK®-333, BYK®-344, BYK®-345, BYK®-346 and Byk®-348.
  • Tego TEGO® Wet KL 245, TEGO® Wet 250, TEGO® Wet 260, TEGO® Wet 500, TEGO® Wet 505, TEGO® Wet 510
  • BYK as BYK®-306, BYK®-307, BYK®-310, BYK®-333, BYK®-344, BYK®-345, BYK®-346 and Byk®-348.
  • the auxiliaries in group c4) are optionally employed in a proportion of from about 0 to 3.0% by weight, preferably from about 0 to 1 .5% by weight, based on the total weight of the liquid-crystalline composition.
  • the wetting and dispersion auxiliaries in group c5) serve, in particular, to prevent the flooding and floating and the sedimentation of pigments and are therefore, if necessary, suitable in particular in pigmented compositions.
  • auxiliaries stabilize pigment dispersions essentially through electrostatic repulsion and/or steric hindrance of the pigment particles containing these additives, where, in the latter case, the interaction of the auxiliary with the ambient medium (for example binder) plays a major role.
  • Such wetting and dispersion auxiliaries are commercially available, for example from Tego, as , TEGO® Dispers 630, , TEGO® Dispers 705, TEGO® Dispers 710, TEGO® Dispers 740 W and from BYK as Disperbyk®, Disperbyk®-107, Disperbyk®-108, Disperbyk®-110, Disperbyk®-111 , Disperbyk®-115, Disperbyk®-130, Disperbyk®-160, Disperbyk®-161 , Disperbyk®-162, Disperbyk®-163, Disperbyk®-164, 1 Disperbyk®-165, Disperbyk®-166, Disperbyk®-167, Disperbyk®-170, Disperbyk®-174, Disperbyk®-180, Disperbyk®-181 , Disperbyk®-182, Disperbyk®-183, Disperbyk®-184, Disperbyk®-185, Disperbyk
  • the hydrophobicizing agents in group c6) can be used to give water-repellent properties to prints or coatings produced, for example, using compositions according to the invention. This prevents or at least greatly suppresses swelling due to water absorption and thus a change in, for example, the optical properties of such prints or coatings.
  • the composition when used, for example, as a printing ink in offset printing, water absorption can thereby be prevented or at least greatly reduced.
  • Such hydrophobicizing agents are commercially available, for example, from Tego as, Tego® Phobe 1000, Tego® Phobe 1000 S, Tego® Phobe 1010, Tego® Phobe 1030, Tego® Phobe 1010, Tego® Phobe 1010, Tego® Phobe 1030, Tego® Phobe 1040, Tego® Phobe 1050, Tego® Phobe 1200, Tego® Phobe 1300, Tego® Phobe 1310 Tego® Phobe 1409, Tego® Phobe 1500 N, Tego® Phobe 1650, Tego® Phobe 1659, Tego® Phobe 6010, Tego® Phobe 6510 and Tego® Phobe 1400.
  • the auxiliaries in group c6) are optionally employed in a proportion of from about 0 to 5.0% by weight, preferably from about 0 to 3.0% by weight, based on the total weight of the polymerizable LC medium.
  • adhesion promoters from group c7) serve to improve the adhesion of two interfaces in contact. It is directly evident from this that essentially the only fraction of the adhesion promoter that is effective is that located at one or the other or at both interfaces. If, for example, it is desired to apply liquid or pasty printing inks, coating compositions or paints to a solid substrate, this generally means that the adhesion promoter must be added directly to the latter or the substrate must be pre-treated with the adhesion promoters (also known as priming), i.e. this substrate is given modified chemical and/or physical surface properties.
  • the substrate has previously been primed with a primer
  • the adhesion properties between the substrate and the primer, but also between the substrate and the printing ink or coating composition or paint play a part in adhesion of the overall multilayer structure on the substrate.
  • Adhesion promoters in the broader sense which may be mentioned are also the substrate wetting auxiliaries already listed under group c4), but these generally do not have the same adhesion promotion capacity.
  • Adhesion promoters based on silanes are, for example, 3-aminopropyltrimethoxysilane, 3- aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, N-aminoethyl-3- aminopropyltrimethoxysilane, N-aminoethyl-3-aminopropylmethyldimethoxysilane, N-methyl-3- aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3- glycidyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane and vinyltrimethoxysilane.
  • silanes are commercially available from Huis, for example under the tradename DYNASILAN®.
  • additives are to be added as auxiliaries from group c7) to the polymerizable LC mediums according to the invention, their proportion optionally corresponds to from about 0 to 5.0% by weight, based on the total weight of the polymerizable LC medium.
  • concentration data serve merely as guidance, since the amount and identity of the additive are determined in each individual case by the nature of the substrate and of the printing/coating composition. Corresponding technical information is usually available from the manufacturers of such additives for this case or can be determined in a simple manner by the person skilled in the art through corresponding preliminary experiments.
  • the auxiliaries for improving the scratch resistance in group c8) include, for example, the abovementioned products TEGO® Rad 2100, TEGO® Rad 2200, TEGO® Rad 2500, and TEGO® Rad 2700, which are available from Tego.
  • the amount data given for group c3) are likewise suitable, i.e. these additives are optionally employed in a proportion of from about 0 to 5.0% by weight, preferably from about 0 to 3.0% by weight, based on the total weight of the liquid-crystalline composition.
  • alkylated monophenols such as 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert- butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4- methylphenol, 2-(a-methylcyclohexyl)-4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2,4,6- tricyclohexylphenol, 2,6-di-tert-butyl-4-methoxymethylphenol, nonylphenols which have a linear or branched side chain, for example 2,6-dinonyl-4-methylphenol, 2,4-dimethyl-6-
  • Hydroquinones and alkylated hydroquinones such as 2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert- butylhydroquinone, 2,5-di-tert-amylhydrocrainone, 2,6-diphenyl-4-octadecyloxyphenol, 2,6-di-tert- butylhydroquinone, 2,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4- hydroxyphenyl stearate and bis(3,5-di-tert-butyl-4-hydroxyphenyl)adipate,
  • Tocopherols such as a-tocopherol, p-tocopherol, y-tocopherol, b-tocopherol and mixtures of these compounds, and tocopherol derivatives, such as tocopheryl acetate, succinate, nicotinate and polyoxyethylenesuccinate (“tocofersolate”), hydroxylated diphenyl thioethers, such as 2,2'-thiobis(6-tert-butyl-4-methylphenol), 2,2'-thiobis(4-octylphenol), 4,4'-thiobis(6-tert-butyl-3-methylphenol), 4,4'-thiobis(6-tert-butyl-2-methylphenol), 4,4'-thiobis(3,6-di-sec- amylphenol) and 4,4'-bis(2,6-dimethyl-4-hydroxyphenyl)disulfide,
  • tocopherol derivatives such as tocopheryl acetate, succinate, nicot
  • Alkylidenebisphenols such as 2,2'-methylenebis(6-tert-butyl-4-methylphenol), 2,2'-methylenebis(6-tert-butyl- 4-ethylphenol), 2,2'-methylenebis[4-methyl-6-(a-methylcyclohexyl)phenol], 2,2'-methylenebis(4-methyl-6- cyclohexylphenol), 2,2'-methylenebis(6-nonyl-4-methylphenol), 2,2'-methylenebis(4,6-di-tert-butylphenol), 2,2- ethylidenebis(4,6-di-tert-butylphenol), 2,2'-ethylidenebis(6-tert-butyl-4-isobutylphenol), 2,2'-methylenebis[6-(a- methylbenzyl)-4-nonylphenol], 2,2'-methylenebis[6-(a,a-dimethylbenzyl)-4-nonylphenol
  • O-, N- and S-benzyl compounds such as 3,5,3',5'-tetra-tert-butyl-4,4'-dihydroxydibenzyl ether, octadecyl 4- hydroxy-3,5-dimethylbenzylmercaptoacetate, tridecyl 4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate, tris(3,5-di-tert-butyl-4-hydroxybenzyl)amine, bis(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)dithioterephthalate, bis(3,5-di-tert-butyl-4-hydroxybenzyl)sulfide and isooctyl-3,5-di-tert-butyl-4-hydroxybenzylmercaptoacetate, aromatic hydroxybenzyl compounds, such as 1 ,3,5-tris(3,5-di-tert-butyl-4-hydroxy
  • Triazine compounds such as 2,4-bis(octylmercapto)-6-(3,5-di-tert-butyl-4-hydroxyanilino)-1 ,3,5-triazine, 2- octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyanilino)-1 ,3,5-triazine, 2-octylmercapto-4,6-bis(3,5-di-tert- butyl-4-hydroxyphenoxy)-1 ,3,5-triazine, 2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenoxy)-1 ,2,3-triazine, 1 ,3,5- tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1 ,3,5-tris(4-tert-butyl-3-hydroxy-2,6- dimethylbenzyl)isocyanurate, 2,4,
  • Benzylphosphonates such as dimethyl 2,5-di-tert-butyl-4-hydroxybenzylphosphonate, diethyl 3,5-di-tert-butyl- 4-hydroxybenzylphosphonate, dioctadecyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate and dioctadecyl 5- tert-butyl-4-hydroxy-3-methylbenzylphosphonate,
  • Acylaminophenols such as 4-hydroxylauroylanilide, 4-hydroxystearoylanilide and octyl N-(3,5-di-tert-butyl-4- hydroxyphenyl)carbamate,
  • Propionic and acetic esters for example of monohydric or polyhydric alcohols, such as methanol, ethanol, n- octanol, i-octanol, octadecanol, 1 ,6-hexanediol, 1 ,9-nonanediol, ethylene glycol, 1 ,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N'-bis(hydroxyethyl)oxalamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane and 4-hydroxymethyl-1 -phospha-2,6,7-trioxabicyclo[2.2.2]-octane,
  • Propionamides based on amine derivatives such as N,N'-bis(3,5-di-tert-butyl-4- hydroxyphenylpropionyl)hexamethylenediamine, N,N'-bis(3,5-di-tert-butyl-4- hydroxyphenylpropionyl)trimethylenediamine and N,N'-bis(3,5-di-tert-butyl-4- hydroxyphenylpropionyl)hydrazine,
  • Ascorbic acid (Vitamin C) and ascorbic acid derivatives, such as ascorbyl palmitate, laurate and stearate, and ascorbyl sulfate and phosphate,
  • Antioxidants based on amine compounds such as N,N'-diisopropyl-p-phenylenediamine, N,N'-di-sec-butyl-p- phenylenediamine, N,N'-bis(1 ,4-dimethylpentyl)-p-phenylenediamine, N,N'-bis(1-ethyl-3-methylpentyl)-p- phenylenediamine, N,N'-bis(1-methylheptyl)-p-phenylenediamine, N,N'-dicyclohexyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamine, N,N'-bis(2-naphthyl)-p-phenylenediamine, N-isopropyl-N'-phenyl-p- phenylenediamine, N-(1 ,3-dimethylbutyl)-N'
  • Phosphines, Phosphites and phosphonites such as triphenylphosnine triphenylphosphite, diphenyl alkyl phosphite, phenyl dialkyl phosphite, tris(nonylphenyl)phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl)phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4- methylphenyl)pentaerythritol diphosphite, diisodecyloxy pentaery
  • 2-(2'-Hydroxyphenyl)benzotriazoles such as 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(3',5'-di-tert- butyl-2'-hydroxyphenyl)benzotriazole, 2-(5'-tert-butyl-2'-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'- (1 ,1 ,3,3-tetramethylbutyl)phenyl)benzotriazole, 2-(3',5'-di-tert-butyl-2'-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3'-tert-butyl-2'-hydroxy-5'-methylphenyl)-5-chlorobenzotriazole, 2-(3'-sec-butyl-5'-tert-butyl-2'- hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-4'-octyloxypheny
  • 2-hydroxybenzophenones such as the 4-hydroxy, 4-methoxy, 4-octyloxy, 4-decycloxy, 4-dodecyloxy, 4- benzyloxy, 4,2',4'-trihydroxy and 2'-hydroxy-4,4'-dimethoxy derivatives,
  • Esters of unsubstituted and substituted benzoic acids such as 4-tert-butylphenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoylresorcinol, bis(4-tert-butylbenzoyl)resorcinol, benzoylresorcinol, 2,4-di-tert- butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl-3, 5-di-tert-butyl-4-hydroxybenzoate, octadecyl-
  • Acrylates such as ethyl a-cyano-p,[3-diphenylacrylate, isooctyl a-cyano-p,[3-diphenylacrylate, methyl a- methoxycarbonylcinnamate, methyl a-cyano-p-methyl-p-methoxycinnamate, butyl-a-cyano-p-methyl-p- methoxycinnamate and methyl-a-methoxycarbonyl-p-methoxycinnamate, sterically hindered amines, such as bis(2,2,6,6-tetramethylpiperidin-4-yl)sebacate, bis(2,2,6,6-tetramethylpiperidin-4-yl)succinate, bis(1 , 2, 2,6,6- pentamethylpiperidin-4-yl)sebacate, bis(1 -octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)sebac
  • Oxalamides such as 4,4'-dioctyloxyoxanilide, 2,2'-diethoxyoxanilide, 2,2'-dioctyloxy-5,5'-di-tert-butoxanilide, 2,2'-didodecyloxy-5,5'-di-tert-butoxanilide, 2-ethoxy-2'-ethyloxanilide, N,N'-bis(3- dimethylaminopropyl)oxalamide, 2-ethoxy-5-tert-butyl-2'-ethoxanilide and its mixture with 2-ethoxy-2'-ethyl- 5,4'-di-tert-butoxanilide, and mixtures of ortho-, para-methoxy-disubstituted oxanilides and mixtures of ortho- and para-ethoxy-disubstituted oxanilides, and
  • 2-(2-hydroxyphenyl)-1 ,3,5-triazines such as 2,4,6-tris-(2-hydroxy-4-octyloxyphenyl)-1 ,3,5-triazine, 2-(2- hydroxy-4-octyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1 ,3,5-triazine, 2-(2,4-dihydroxyphenyl)-4,6-bis(2,4- dimethylphenyl)-1 ,3,5-triazine, 2,4-bis(2-hydroxy-4-propyloxyphenyl)-6-(2,4-dimethylphenyl)-1 ,3,5-triazine, 2- (2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl)-1 ,3,5-triazine, 2-(2-hydroxy-4-dodecyloxyphenyl)-4,6- bis(2,4-dimethylphenyl)-1 ,3,5
  • the polymerizable LC medium comprises one or more specific antioxidant additives, preferably selected from the Irganox® series, e.g. the commercially available antioxidants lrganox®1076 and lrganox®1010, from Ciba, Switzerland.
  • specific antioxidant additives preferably selected from the Irganox® series, e.g. the commercially available antioxidants lrganox®1076 and lrganox®1010, from Ciba, Switzerland.
  • the polymerizable LC medium comprises one or more, more preferably two or more photoinitiators, for example, selected from the commercially available Irgacure® or Darocure® (Ciba AG) series, in particular, Irgacure 127, Irgacure 184, Irgacure 369, Irgacure 651 , Irgacure 817, Irgacure 907, Irgacure 1300, Irgacure, Irgacure 2022, Irgacure 2100, Irgacure 2959, or Darcure TPO.
  • Irgacure® or Darocure® Darocure®
  • the polymerizable LC medium comprises preferably one or more oxime ester photoinitiators preferably selected from the commercially available OXE02 (Ciba AG), NCI 930, N1919T (Adeka), SPI-03 or SPI-04 (Samyang).
  • the concentration of the polymerization initiator(s) as a whole in the polymerizable LC medium is preferably from 0.5 to 10%, very preferably from 0.8 to 8%, more preferably 1 to 6%.
  • the polymerizable LC medium comprises a given ratio between the concentration of the photoinitiator and the concentration of all chiral compounds as a whole, which is in the range from 1 :1 to 1 :5, more preferably in the range from 1 :1 to 1 :4, even more preferably in the range from 1 :1 to 1 :3.
  • the polymerizable LC medium is dissolved in a suitable solvent, which are preferably selected from organic solvents.
  • the solvents are preferably selected from ketones such as acetone, methyl ethyl ketone, methyl propyl ketone, methyl isobutyl ketone or cyclohexanone; acetates such as methyl, ethyl or butyl acetate or methyl acetoacetate; alcohols such as methanol, ethanol or isopropyl alcohol; aromatic solvents such as toluene or xylene; alicyclic hydrocarbons such as cyclopentane or cyclohexane; halogenated hydrocarbons such as di- or trichloromethane; glycols or their esters such as PGMEA (propyl glycol monomethyl ether acetate), ⁇ - butyrolactone. It is also possible to use binary, ternary or higher mixtures of the above solvents.
  • the total concentration of all solids, including the RMs, in the solvent(s) is preferably from 10 to 60%.
  • the polymerizable LC medium comprises, a) one or more di- or multireactive polymerizable mesogenic compounds, b) optionally one or more monoreactive polymerizable mesogenic compounds, preferably selected from compounds of formula MRM 8, MRM9 and/or MRM10 and their corresponding subformulae, c) in case of the cholesteric polymer film, one or more chiral mesogenic compounds, preferably selected from compounds of formula CRA or CRB, more preferably of CRB and its subformulae, d) optionally one or more antioxidative additives, e) optionally one or more adhesion promotors, f) optionally one or more surfactants, g) optionally one or more mono-, di- or multireactive polymerizable non-mesogenic compounds, h) optionally one or more dyes showing an absorption maximum at the wavelength used to initiate photo polymerization,
  • the polymerizable LC medium comprises, a) one or more di- or multireactive polymerizable mesogenic compounds, b) optionally one or more monoreactive polymerizable mesogenic compounds, preferably selected from compounds of formula MRM 8, MRM9 and/or MRM10 and their corresponding subformulae, c) in case of the cholesteric polymer film, one or more chiral mesogenic compounds, preferably selected from compounds of formula CRA or CRB, more preferably of CRB and its subformulae, d) optionally one or more antioxidative additives, e) optionally one or more adhesion promotors, f) optionally one or more surfactants, g) optionally one or more mono-, di- or multireactive polymerizable non-mesogenic compounds, h) optionally one or more dyes showing an absorption maximum at the wavelength used to initiate photo polymerization,
  • the optical component is typically prepared by a method comprising the steps of
  • the coating order of the above described layers is not important for the optical effects to be achieved, however the light input direction into the optical component is a factor that has to be considered while applying the optical component to the optical or electrooptical device.
  • the polymerizable LC medium can be coated or printed onto the substrate, for example by spincoating, printing, or other known techniques, and the solvent is evaporated off before polymerization. In most cases, it is suitable to heat the mixture in order to facilitate the evaporation of the solvent.
  • the polymerizable LC medium can be applied onto a substrate by conventional coating techniques like spin coating, bar coating or blade coating. It can also be applied to the substrate by conventional printing techniques which are known to the expert, like for example screen printing, offset printing, reel-to-reel printing, letter press printing, gravure printing, rotogravure printing, flexographic printing, intaglio printing, pad printing, heat-seal printing, ink-jet printing or printing by means of a stamp or printing plate.
  • Suitable substrate mediums and substrates are known to the expert and described in the literature, as for example conventional substrates used in the optical films industry, such as glass or plastic.
  • Especially suitable and preferred substrates for polymerization are polyester such as polyethyleneterephthalate (PET) or polyethylenenaphthalate (PEN), polyvinylalcohol (PVA), polycarbonate (PC) triacetylcellulose (TAC), or cyclo olefin polymers (COP), or commonly known color filter materials, in particular triacetylcellulose (TAC), cyclo olefin polymers (COP), or commonly known colour filter materials.
  • PET polyethyleneterephthalate
  • PEN polyethylenenaphthalate
  • PVA polyvinylalcohol
  • PC polycarbonate
  • TAC triacetylcellulose
  • COP cyclo olefin polymers
  • color filter materials in particular triacetylcellulose (TAC), cyclo olefin polymers (COP), or commonly known colour filter materials.
  • the Friedel-Creagh-Kmetz rule can be used to predict whether a mixture will adopt planar or homeotropic alignment, by comparing the surface energies of the RM layer (YRM) and the substrate (y s ):
  • planar alignment is by coating the substrate with a polyimide layer, and then rubbing the alignment layer with a velvet cloth.
  • suitable planar alignment layers are known in the art, like for example rubbed polyimide or alignment layers prepared by photoalignment as described in US 5,602,661 , US 5,389,698 or US 6,717,644.
  • the process according to the invention contains a process step where the polymerisable LC medium either for the first or for the second polymer film or even both polymer films is allowed to rest for a period of time in order to evenly redistribute the polymerisable LC medium on the substrate or the first polymer film (herein referred to as “annealing”).
  • the layer stack is annealed for a time between 10 seconds and 1 hour, preferably between 20 seconds and 10 minutes and most preferably between 30 seconds and 2 minutes.
  • the annealing is preferably performed at room temperature.
  • the annealing is performed at elevated temperature, preferably above 20°C and below 120°C, more preferably above 40°C and below 100°C and most preferably above 50°C and below 80°C.
  • the layer stack is cooled down to room temperature after annealing at an elevated temperature.
  • the cooling can be perfomed actively with the help of cooling aids or passively just by letting the layer stack rest for a given time.
  • the polymerizable LC medium in the 1 st UV step is exposed to actinic radiation as described for example in WO 01/20394, GB 2,315,072 or WO 98/04651 .
  • Actinic radiation means irradiation with light, like UV light, IR light or visible light, irradiation with X-rays or gamma rays, or irradiation with high-energy particles, such as ions or electrons.
  • the 1 st UV step is carried out by photo irradiation, in particular with UV light, especially with UVA light.
  • a source for actinic radiation for example a single UV lamp or a set of UV lamps can be used. When using a high lamp power the curing time can be reduced.
  • Another possible source for photo radiation is a laser, like e.g. a UV laser, an IR laser, or a visible laser.
  • the curing time in each step is each and idependently, dependent, inter alia, on the reactivity of the photoreactive compounds, the thickness of the coated layer, and the power and selected wavelength of the UV lamp.
  • the curing time is preferably ⁇ 5 minutes, very preferably ⁇ 3 minutes, most preferably ⁇ 1 minute. For mass production, short curing times of ⁇ 30 seconds are preferred.
  • a suitable UV radiation power in each step is each and idependently and preferably in the range from 5 to 300 mWcm-2, more preferably in the range from 50 to 250 mWcnr 2 and most preferably in the range from 100 to 180 mWcirr 2 .
  • a suitable UV dose in each step is each and idependently is preferably in the range from 20 to 1000 mJcm' 2 more preferably in the range from 40 to 800 mJcm' 2 and most preferably in the range from 40 to 500 mJcnr 2 .
  • the curing in each step is each and idependently and preferably performed in air.However it is likewise preferably that the curing step is performed under an inert gas atmosphere, such as preferably nitrogen.
  • the curing in each step is each and idependently and preferably performed at a temperature from 1 to 70°C, more preferably 5 to 50°C, even more preferably 15 to 30°C, most preferably at room temperature.
  • each polymerized LC film according to the present invention is determined by the optical properties desired from the film or the final product.
  • each of the polymer films have typically a thickness of from 0.5 to 10 pm, very preferably from 0.5 to 5 pm, in particular from 0.5 to 3 pm.
  • the resulting layer stack of polymer films or the final optical component can be removed from the substrate and combined with other substrates or further optical films by a laminating process known by the skilled person.
  • Suitable substrates and optical films are given above and include especially polarisers.
  • optical component according to the present invention can be used in displays of the transmissive or reflective type, especially they can be used in conventional OLED displays or LCDs, in particular OLED displays.
  • Irganox1076 is a stabilizer, being commercially available (Ciba AG, Basel, Switzerland).
  • NCI-930 is a photoinitiator, being commercially available (Adeka Coorporation, Japan).
  • BYK-310 is a surfactant being commercially available (BYK, Germany).
  • the mixtures are each transformed to corresponding solutions by dissolving the solids in a solvent blend of toluene: cyclohexanone (7:3), at a ratio of 30% mixture M1 or M2 to 70% solvent by mass, respectively.
  • the solution of mixture M1 is then spin coated at 5000rpm for 30s on a commercially available glass substrate covered with polyimide.
  • the coated film is than annealed on a hotplate at 60°C for 60s and subsequently cooled via an applied N2 purge (20l/min) with a circulator (20°C) for 60s. Curing is performed with a high pressure mercury lamp (LH6 fusion) at 10m/min with 77% power (200mJ/cm 2 ), while applying further the N2 purge.
  • the solution of mixture M2 is then spin coated at 4000rpm for 30s on top of polymer film 1 obtained from M1 .
  • the layer stack is annealed on a hotplate at 60°C for 60s and subsequently cooled via an applied N2 purge (20l/min.) with a circulator (20°C) for 60s. Curing is performed with a high pressure mercury lamp (LH6 fusion) at 10m/min with 77% power (200mJ/cm 2 ), while applying further the N2 purge.
  • the resulting optical component exhibits reverse optical dispersion.
  • the retardation profile is close to the ideal quarter wave retardation at all viewing angles and visible wavelengths.
  • the on-axis dispersion is 0.870 while the dispersion value increases with the viewing angle and the corresponding angular dispersion profile is approximately symmetrical.
  • the retardation profile for the wavelength of 450 nm, 550 nm and 650 nm have all the characteristics of planarly alignment polymer film of optical component. At lower wavelengths occurs typically less retardation variation with the angle of incidence.
  • the retardation profile (Retardation [nm]/Angle of incidence [°]), angular retardation (R450/R550 / Angle of Incidence [°]) and optical dispersion (Retardation [nm]/Wavelength [nm]) are measured via ellipsometry.
  • An anti-reflection stack is created by arranging the optical component between a reflective surface, such as a metallic cathode of an OLED display, and a linear polariser.
  • a reflective surface such as a metallic cathode of an OLED display
  • a linear polariser In comparison to a standard planar aligned film according to such as, for example described in WO 2016/020035 A1 the optical component according to the invention exhibits much dark reflection.
  • the material cost for the optical component is much reduced compared to other reverse dispersion application methods such as, for example described in WO 2016/020035 A1 , making this a potentially viable commercial alternative for anti-reflection productions due to its simplicity and compatibility to methods of mass production.

Abstract

The invention relates to an optical component exhibiting a reverse or negative optical dispersion profile comprising two or more liquid crystalline polymer films, wherein the first utilized polymer film exhibits a uniform planar alignment of the polymerised LC molecules and the second polymer film adjacent to the first polymer film exhibits a cholesteric alignment of the polymerised LC molecules having a ¼ pitch rotation through the film thickness of the second polymer film. Furthermore, the present invention relates also to a method for its preparation. These optical components may be used for purposes suh as, for example, adjusting optical properties of a liquid crystal display (LCD), improving light utilization efficiency, or ensuring anti-reflectivity and visibility in an organic light emitting device (OLED), or even for AV/VR applications. Accordingly, the invention relates further to the use of such optical components for optical, electro-optical, decorative or security applications and to corresponding devices as such.

Description

Polymerisable Liquid Crystal Medium and Polymerised Liquid Crystal Film
Technical Field of the Invention
The invention relates to an optical component exhibiting a reverse or negative optical dispersion profile comprising two or more liquid crystalline polymer films, wherein the first utilized polymer film exhibits a uniform planar alignment of the polymerised LC molecules and the second polymer film adjacent to the first polymer film exhibits a cholesteric alignment of the polymerised LC molecules having a % pitch rotation through the film thickness of the second polymer film. Furthermore, the present invention relates also to a method for its preparation. These optical components may be used for purposes such as, for example, adjusting optical properties of a liquid crystal display (LCD), improving light utilization efficiency, or ensuring anti-reflectivity and visibility in an organic light emitting device (OLED), or even for AVA/R applications. Accordingly, the invention relates further to the use of such optical components for optical, electro-optical, decorative or security applications and to corresponding devices as such.
Background and Prior Art
OLED displays are constructed with a metallic cathode which has high reflectivity and acts like a mirror. It is important that the viewer only sees the light emitted by the OLED and not light incident reflected off the display. To achieve this an anti-reflection layer or anti reflection stack is required in the display.
Typically a circular polariser will be employed to optically isolate incident light and remove reflection. The circular polariser consists of a linear polariser combined with a quarter wave retarder. To prevent any reflected light leaving the system the quarter wave plate (QWP) must have an optical retardation that matches exactly one quarter of the wavelength of the incident light. Ideally the QWP should be achromatic, so it performs equally well for all visible wavelengths. In this regard, the ambient contrast ratio (ACR) is an important figure of merit for OLED devices which may need to be viewed in bright sunlight.
Standard quarter wave plate materials have positive dispersion characteristics, i.e. the birefringence decreases with increasing wavelength. These positive dispersion QWP films have good anti-reflection performance only at a single wavelength (typically 550nm). Higher-end QWP films have negative dispersion (ND) characteristics, i.e. the birefringence increases with increasing wavelength. A negative dispersion film typically shows a quarter wave retardance at a wider wavelength range to a positive dispersion film, this leads to an achromatic antireflection performance.
Standard transparent materials have positive optical dispersion, the refractive index reduces with increasing wavelength. An RM film with standard optical dispersion produces a QWP which converts linearly polarised input light to perfectly circular polarised light, and vice versa, for only a single wavelength. All other wavelengths will be converted to a nonideal elliptical polarisation state, a portion of this light will not be absorbed by the polariser after reflection and be transmitted to the viewer. This results in poor anti-reflection and a screen which may look purple rather than black.
To produce an achromatic QWP the retarder must have reverse (also known as negative) optical dispersion, the refractive index increases with increasing wavelength. One way to make a reverse optical dispersion QWP is to combine a half wave plate (HWP) with positive optical dispersion with a QWP with positive optical dispersion. These two retarders must be laminated with their directors perpendicular to each other. The problem with this solution is increased process cost from having to coat two separate films and then laminate them together. There is also reduced yield due to the lamination cutting process.
Suitable optical films for this purpose are typically based on polymerisable liquid crystal materials, typically exhibiting a wavelength dependent retardation. In this regard, three main kind of optical behaviour are known: i) “Normal” or “Positive” optical dispersion, such as for example described in EP 0 940 707 B1 ii) “Reverse” or “Negative” optical dispersion, such as, for example described in WO 2016/020035 A1 , and iii) “Flat” optical dispersion, such as for example described in WO 2009/058396 A1 .
For example, flat or negative dispersion polymerisable liquid crystal materials can be produced by adding at least one component with an ordinary refractive index (n0) higher than extraordinary refractive index (ne) in the formulation. Therefore, highly conjugated substituents are required in the orthogonal position with respect to the long-axis of the molecules. The latter materials absorb part of the UV dose when curing optical films which results in poor degree of cure and poor thermal durability of cured films. Besides the latter molecular blocks can easily oxidise under high temperatures in the presence of oxygen. Same applies to high birefringent formulations containing highly conjugated reactive mesogens which reduces the thermal durability of cured films and which are typically prone to yellowing.
For example, WO 2008/1 19427 A1 describes a birefringent polymer film with negative optical dispersion, which is obtainable from a polymerisable LC medium comprising as negative dispersion component compounds having the H shape.
Suitable materials having a T-Shape and corresponding birefringent polymer films with negative optical dispersion are disclosed e.g. in US 2015175564, WO 17079867 A1 , WO16104317 A, US 2015277007 A1 , or WO 16171041 A1 and in particular include compounds represented by formulae 1 to 5 of US 2015175564 A1 , compounds represented by formulae (1-1) to (I-5), (I-8), (1-14), (1-16) to (I-36), (1-41), (I-54) to (I-65), (I-75) to (I-80), (I-82), (I-83), (I-86) to (I-97) and (1-121) to (1-125) of WO 17/079867 A1 , compounds represented by formulae (A12-16) to (A12-18), (A14-1) to (A14-3) and (A141 -1) to (A143-2) of WO 16104317 A1 , compounds represented by formulae (2-A) to (2-D), (3-A) to (3-D), (4-A) to (4-D), (5-A) to (5-D), (7-A) to (7-D), (8-A) to (8- D), (9-A) to (9-D), (1 1 -B) to (1 1 -D), (12-b) to (12-D), (13-B) to (13-D), (22-B) to (22-D), (25-B) to (25-D), (40-A) to (40-D), (41 -A) to (41 -D), (42-A) to (42-D), (43-A) to (43-D), (44-A) to (44-D), (50-A) to (50-D), (52-A) to (52- D), (54-A) to (54-D), (55-A) to (55-D), or (56 -A) to (56-D) of US 2015/0277007 A1 , compounds represented by formulae (A) to (E) of WO 16171041 A1 ,
However, the bulky nature of the negative dispersion compounds according to the prior art are typically hard to align or give formulations with a narrow process window for annealing temperature, which is not convenient for mass production. Also, the polymer film is normally weaker and less resistant to heat. However, the main disadvantage is that the cost of synthesis of the T-shape and H-shape materials is much higher than standard LC molecules due the increased number of synthesis steps. A cheaper alternative to the typical reverse dispersion films would allow competitiveness in a wider range of markets particularly for OLED TV. Ravi K. Komanduri, Kristopher F. Lawler, and Michael J. Escuti (14 January 2013 / Vol. 21 , No. 1 / OPTICS EXPRESS 404) disclose Multi-Twist Retarders (MTRs) which are liquid crystal polymer films with chiral additives used to give them ideal optical properties over a range of bandwidths. By using different combinations (1-3 layers) of different chiral (RHS, LHS, none), achromatic retarders can be produced with varying efficiency. Further approaches in view of the above-defined technical problem are for instance disclosed in US 2013-286479 A, US 2010-225876 A, US 2010-225856 A, US 2010-110362 A, US 2008- 158490 A, US 2004- 032677 A, JP 2002-062540 A1 , US 6,693,746 B, US 2003-202137 A, US 6,480,251 B, and US 6,061 ,108 B.
In particular, US 9,298,041 B discloses a multi-layer twisted retarder arrangement that includes two or three twisted layers configured to provide broadband retardance for a wide field of view, for example, by varying the number of layers, twist angles, and/or thickness of each layer.
However, there is still the need for new and preferably improved, optical components not exhibiting the drawbacks of prior art materials or if do so, only exhibiting them to a less extent.
Other aims of the present invention are immediately evident to the person skilled in the art from the following detailed description.
Surprisingly, the inventors of the present invention have found that one or more, preferably all of the above requirements can be fufilled, preferably at the same time, by using a polymerisable LC medium according to claim 1 .
Summary of the Invention
The invention relates to an optical component exhibiting a reverse or negative optical dispersion profile comprising two or more liquid crystalline polymer films, wherein the first utilized polymer film exhibits a uniform planar alignment of the polymerised LC molecules and the second polymer film adjacent to the first polymer film exhibits a cholesteric alignment of the polymerised LC molecules having a % pitch rotation through the film thickness of the second polymer film.
The invention further relates to a method of production for an optical component as described above and below.
The invention especially relates to the use of an optical component as described above and below, in an optical, electronic or electro optical device.
The invention further relates to an optical, electronic or electro optical component or device as such, comprising an optical component as described above and below.
Said devices include, without limitation, electro optical displays, such as OLED and LCDs, non-linear optic (NLO) devices, optical information storage devices, electronic devices, electroluminescent displays, organic photovoltaic (OPV) devices, lighting devices, sensor devices, electro photographic recording devices, organic memory devices or devices for AR/VR applications. Terms and Definitions
As used herein, the term "polymer" will be understood to mean a molecule that encompasses a backbone of one or more distinct types of repeating units (the smallest constitutional unit of the molecule) and is inclusive of the commonly known terms ‘‘oligomer’’, ‘‘copolymer’’, ‘‘homopolymer’’ and the like. Further, it will be understood that the term polymer is inclusive of, in addition to the polymer itself, residues from initiators, catalysts, and other elements attendant to the synthesis of such a polymer, where such residues are understood as not being covalently incorporated thereto. Further, such residues and other elements, while normally removed during post polymerisation purification processes, are typically mixed or co-mingled with the polymer such that they generally remain with the polymer when it is transferred between vessels or between solvents or dispersion media.
The term “(meth)acrylic polymer" as used in the present invention includes a polymer obtained from acrylic monomers, a polymer obtainable from methacrylic monomers, and a corresponding co-polymer obtainable from mixtures of such monomers.
The term ‘‘polymerisation’’ means the chemical process to form a polymer by bonding together multiple polymerisable groups or polymer precursors (polymerisable compounds) containing such polymerisable groups.
The terms "film" and "layer" include rigid or flexible, self-supporting or freestanding films with mechanical stability, as well as coatings or layers on a supporting substrate or between two substrates.
The term "liquid crystal or mesogenic compound" means a compound comprising one or more calamitic (rod- or board/lath-shaped) or discotic (disk-shaped) mesogenic groups. The term "mesogenic group" means a group with the ability to induce liquid crystal (LC) phase behaviour. The compounds comprising mesogenic groups do not necessarily have to exhibit an LC phase themselves. It is also possible that they show LC phase behaviour only in mixtures with other compounds, or when the mesogenic compounds or materials, or the mixtures thereof, are polymerised. For the sake of simplicity, the term "liquid crystal" is used hereinafter for both mesogenic and LC materials. For an overview of definitions see C. Tschierske, G. Pelzl and S. Diele, Angew. Chem. 2004, 116, 6340-6368.
A calamitic mesogenic group is usually comprising a mesogenic core consisting of one or more aromatic or non-aromatic cyclic groups connected to each other directly or via linkage groups, optionally comprising terminal groups attached to the ends of the mesogenic core, and optionally comprising one or more lateral groups attached to the long side of the mesogenic core, wherein these terminal and lateral groups are usually selected e.g. from carbyl or hydrocarbyl groups, polar groups like halogen, nitro, hydroxy, etc., or polymerisable groups.
The term "reactive mesogen" (RM) means a polymerisable mesogenic or liquid crystal compound.
Polymerisable compounds with one polymerisable group are also referred to as "monoreactive" compounds, compounds with two polymerisable groups as "direactive" compounds, and compounds with more than two polymerisable groups as "multireactive" compounds. Compounds without a polymerisable group are also referred to as "non-reactive" compounds. The term “non-mesogenic compound or material” means a compound or material that does not contain a mesogenic group as defined above.
Visible light is electromagnetic radiation that has a wavelength in a range from about 400 nm to about 740 nm. Ultraviolet (UV) light is electromagnetic radiation with a wavelength in a range from about 200 nm to about 450 nm.
According to the present application, the term "linearly polarised light" means light, which is at least partially linearly polarized. Preferably, the aligning light is linearly polarized with a degree of polarization of more than 5:1 . Wavelengths, intensity and energy of the linearly polarised light are chosen depending on the photosensitivity of the photoalignable material. Typically, the wavelengths are in the UV-A, UV-B and/or UV-C range or in the visible range. Preferably, the linearly polarised light comprises light of wavelengths less than 450 nm, more preferably less than 420 nm at the same time the linearly polarised light preferably comprises light of wavelengths longer than 280nm, preferably more than 320nm, more preferably over 350nm.
The Irradiance (Ee) or radiation power is defined as the power of electromagnetic radiation (dO) per unit area (dA) incident on a surface:
Ee = d9/dA.
The radiant exposure or radiation dose (He), is as the irradiance or radiation power (Ee) per time (t):
He = Ee ' t.
All temperatures, such as, for example, the melting point T(C,N) or T(C,S), the transition from the smectic (S) to the nematic (N) phase T(S,N) and the clearing point T(N , I) of the liquid crystals, are quoted in degrees Celsius. All temperature differences are quoted in differential degrees.
The term ‘‘clearing point" means the temperature at which the transition between the mesophase with the highest temperature range and the isotropic phase occurs.
On the molecular level, the birefringence of a liquid crystal depends on the anisotropy of the polarizability (Aa=aira-L). "Polarizability" means the ease with which the electron distribution in the atom or molecule can be distorted. The polarizability increases with greater number of electrons and a more diffuse electron cloud. The polarizability can be calculated using a method described in e.g. Jap. J. Appl. Phys. 42, (2003) p. 3463.
The "optical retardation" at a given wavelength R(/.) (in nm) of a layer of liquid crystalline or birefringent material is defined as the product of birefringence at that wavelength An( ) and layer thickness d (in nm) according to the equation
R(X) = An( ) ■ d The optical retardation R represents the difference in the optical path lengths in nanometres travelled by S- polarised and P-polarised light whilst passing through the birefringent material. "On-axis" retardation means the retardation at normal incidence to the sample surface.
The term "negative (optical) dispersion" refers to a birefringent or liquid crystalline material or layer that exhibits reverse birefringence dispersion where the magnitude of the birefringence (An) increases with increasing wavelength ( ). i . e . , I An(450) I < I An(550) I , or An(450)/An(550) < 1 , where An(450) and An(550) are the birefringence of the material measured at wavelengths of 450nm and 550nm respectively. In contrast, positive (optical) dispersion" means a material or layer having I An(450) I > I An(550) I or An(450)/An(550) > 1 . See also for example A. Uchiyama, T. Yatabe ‘‘Control of Wavelength Dispersion of Birefringence for Oriented Copolycarbonate Films Containing Positive and Negative Birefringent Units". J. Appl. Phys. Vol. 42 pp 6941 -6945 (2003). ‘‘Flat (optical) dispersion" means a material or layer having I An(450) I > I An(550) I or An(450)/An(550) =1 .
Since the optical retardation at a given wavelength is defined as the product of birefringence and layer thickness as described above [R( ) = An( ) ■ d], the optical dispersion can be expressed either as the "birefringence dispersion" by the ratio An(450)/An(550), or as "retardation dispersion" by the ratio R(450)/R(550), wherein R(450) and R(550) are the retardation of the material measured at wavelengths of 450nm and 550nm respectively. Since the layer thickness d does not change with the wavelength, R(450)/R(550) is equal to An(450)/An(550). Thus, a material or layer with negative or reverse dispersion has R(450)/R(550) < 1 or I R(450) I < I R(550) I , a material or layer with positive or normal dispersion has R(450)/R(550) > 1 or | R(450) | > | R(550) | , and a material or layer with flat dispersion has R(450)/R(550) = 1 or | R(450) | = | R(550) | .
In the present invention, unless stated otherwise "optical dispersion" means the retardation dispersion i.e. , the ratio R(450)/R(550).
The term "high dispersion" means that the absolute value of the dispersion shows a large deviation from 1 , whereas the term "low dispersion" means that the absolute value of the dispersion shows a small deviation from 1 . Thus, for example, "high negative dispersion" means that the dispersion value is significantly smaller than 1 , and "low negative dispersion" means that the dispersion value is only slightly smaller than 1 .
The retardation (R(/.)) of a material can be measured using a spectroscopic ellipsometer, for example the M2000 spectroscopic ellipsometer manufactured by J. A. Woollam Co. This instrument can measure the optical retardance in nanometres of a birefringent sample e.g., Quartz over a range of wavelengths typically, 370nm to 2000nm. From this data it is possible to calculate the dispersion (R(450)/R(550) or An(450)/An(550)) of a material.
A method for carrying out these measurements was presented at the National Physics Laboratory (London, UK) by N. Singh in October 2006 and entitled ‘‘Spectroscopic Ellipsometry, Part 1 -Theory and Fundamentals, Part 2 - Practical Examples and Part 3 - measurements". In accordance with the measurement procedures described Retardation Measurement (RetMeas) Manual (2002) and Guide to WVASE (2002) (Woollam Variable Angle Spectroscopic Ellipsometer) published by J. A. Woollam Co. Inc (Lincoln, NE, USA). Unless stated otherwise, this method is used to determine the retardation of the materials, films and devices described in this invention.
The birefringence An is defined as follows
An = ne -n0 wherein ne is the extraordinary refractive index and n0 is the ordinary refractive index, and the effective average refractive index nav is given by the following equation: nav = ((2n0 2 + ne 2)/3) 54
The average refractive index nav and the ordinary refractive index n0 can be measured using an Abbe refractometer. An can then be calculated from the above equations.
A polymerizable LC medium in accordance with the present invention can be prepared, for example, by doping the medium with chiral compounds having a high twisting power. The pitch p of the induced cholesteric helix is then given by the concentration c and the helical twisting power HTP of the chiral compound in accordance with the following equation: p = (HTP c)-1
The total HTP of chiral compounds having the same configuration (HTPtotai) holds then approximately the following equation:
HTPtotai = Zi Ci HTPi wherein ci is the concentration of each individual chiral compound and HTPi is the helical twisting power of each individual chiral compound.
The HTP of all chiral compounds within a mixture of different configurations (IHTPAI) holds then approximately the following equation:
IHTPA I = (Is Cs HTPs) - ((ZrCrHTPr) wherein cs is the concentration of each individual chiral compound with S configuration, HTPs is the helical twisting power of each individual chiral compound having S configuration and wherein cr is the concentration of each individual chiral compound with R configuartion and HTPR is the helical twisting power of each individual chiral compound having R configuration.
The term "director" is known in prior art and means the preferred orientation direction of the long molecular axes (in case of calamitic compounds) or short molecular axes (in case of discotic compounds) of the liquidcrystalline or RM molecules. In case of uniaxial ordering of such anisotropic molecules, the director is the axis of anisotropy. All physical properties have been and are determined according to "Merck Liquid Crystals, Physical Properties of Liquid Crystals", Status Nov. 1997, Merck KGaA, Germany and are given for a temperature of 20 °C, unless explicitly stated otherwise. The optical anisotropy (An) is determined at a wavelength of 589.3 nm
In case of doubt the definitions as given in C. Tschierske, G. Pelzl and S. Diele, Angew. Chem. 2004, 1 16, 6340-6368 shall apply.
Unless explicitly stated otherwise in the given generic formulae, the following terms have the following meanings:
"Carbyl group" denotes a mono- or polyvalent organic group containing at least one carbon atom which either contains no further atoms (such as, for example, -C=C-) or optionally contains one or more further atoms, such as, for example, N, O, S, P, Si, Se, As, Te or Ge (for example carbonyl, etc.). "Hydrocarbyl group" denotes a carbyl group, which additionally contains one or more H atoms and optionally one or more heteroatoms, such as, for example, N, O, S, P, Si, Se, As, Te or Ge.
A carbyl or hydrocarbyl group can be a saturated or unsaturated group. Unsaturated groups are, for example, aryl, alkenyl, or alkynyl groups. A carbyl or hydrocarbyl group having more than 3 C atoms can be straight chain, branched and/or cyclic and may contain spiro links or condensed rings.
Preferred carbyl and hydrocarbyl groups are optionally substituted alkyl, alkenyl, alkinyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy and alkoxycarbonyloxy having 1 to 40, preferably 1 to 25, particularly preferably 1 to 18 C atoms, optionally substituted aryl or aryloxy having 6 to 40, preferably 6 to 25 C atoms, or optionally substituted alkylaryl, arylalkyl, alkylaryloxy, arylalkyloxy, arylcarbonyl, aryloxycarbonyl, arylcarbonyloxy and aryloxycarbonyloxy having 6 to 40, preferably 6 to 25 C atoms.
Further preferred carbyl and hydrocarbyl groups are C1-C40 alkyl, C2-C40 alkenyl, C2-C40 alkinyl, C3-C40 allyl, C4-C40 alkyldienyl, C4-C40 polyenyl, C6-C40 aryl, C6-C40 alkylaryl, C6-C40 arylalkyl, C6-C40 alkylaryloxy, C6-C40 arylalkyloxy, C2-C40 heteroaryl, C4-C40 cycloalkyl, C4-C40 cycloalkenyl, etc. Preference is given to C1-C22 alkyl, C2-C22 alkenyl, C2-C22 alkinyl, C3-C22 allyl, C4-C22 alkyldienyl, C6-C12 aryl, C6-C20 arylalkyl, and C2-C20 heteroaryl.
Further preferred carbyl and hydrocarbyl groups are straight-chain, branched or cyclic alkyl radicals having 1 to 40, preferably 1 to 25 C atoms, more preferably 1 to 12 C atoms, which are unsubstituted or mono- or polysubstituted by F, Cl, Br, I or CN and in which one or more non-adjacent CH2 groups may each be replaced, independently of one another, by -C(RX)=C(RX)-, -C=C-, -N(RX)-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- in such a way that O and/or S atoms are not linked directly to one another.
Above, Rx preferably denotes H, halogen, a straight-chain, branched or cyclic alkyl chain having 1 to 25 C atoms, in which, in addition, one or more non-adjacent C atoms may be replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, and in which one or more H atoms may be replaced by fluorine, an optionally substituted aryl or aryloxy group having 6 to 40 C atoms or an optionally substituted heteroaryl or heteroaryloxy group having 2 to 40 C atoms. Preferred alkyl groups are, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl, n-hexyl, 2-ethylhexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, dodecanyl, trifluoromethyl, perfluoro-n-butyl, 2,2,2-trifluoroethyl, perfluorooctyl, perfluorohexyl, etc.
Preferred alkenyl groups are, for example, ethenyl, propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, etc.
Preferred alkinyl groups are, for example, ethynyl, propynyl, butynyl, pentynyl, hexynyl, octynyl, etc.
Preferred alkoxy groups are, for example, methoxy, ethoxy, 2- meth oxy ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, 2-methylbutoxy, n-pentoxy, n-hexoxy, n-heptyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, n-undecyloxy, n-dodecyloxy, etc.
Preferred amino groups are, for example, dimethylamino, methylamino, methylphenylamino, phenylamino, etc.
Aryl and heteroaryl groups can be monocyclic or polycyclic, i.e. they can have one ring (such as, for example, phenyl) or two or more rings, which may also be fused (such as, for example, naphthyl) or covalently linked (such as, for example, biphenyl), or contain a combination of fused and linked rings. Heteroaryl groups contain one or more heteroatoms, preferably selected from O, N, S and Se.
Preference is given to mono-, bi-, or tricyclic aryl groups having 6 to 25 C atoms and mono-, bi- or tricyclic heteroaryl groups having 2 to 25 C atoms, which optionally contain fused rings, and which are optionally substituted. Preference is furthermore given to 5-, 6- or 7-membered aryl and heteroaryl groups, in which, in addition, one or more CH groups may be replaced by N, S or O in such a way that O atoms and/or S atoms are not linked directly to one another.
Preferred aryl groups are, for example, phenyl, biphenyl, terphenyl, [1 ,1 ':3l,1"]terphenyl-2l-yl, naphthyl, anthracene, binaphthyl, phenanthrene, pyrene, dihydropyrene, chrysene, perylene, tetracene, pentacene, benzopyrene, fluorene, indene, indenofluorene, spirobifluorene, etc.
Preferred heteroaryl groups are, for example, 5-membered rings, such as pyrrole, pyrazole, imidazole, 1 ,2,3- triazole, 1 ,2,4-triazole, tetrazole, furan, thiophene, selenophene, oxazole, isoxazole, 1 ,2-thiazole, 1 ,3-thiazole, 1 ,2,3-oxadiazole, 1 ,2,4-oxadiazole, 1 ,2,5-oxadiazole, 1 ,3,4-oxadiazole, 1 ,2,3-thiadiazole, 1 ,2,4-thiadiazole,
1 .2.5-thiadiazole, 1 ,3,4-thiadiazole, 6-membered rings, such as pyridine, pyridazine, pyrimidine, pyrazine,
1 .3.5-triazine, 1 ,2,4-triazine, 1 ,2,3-triazine, 1 ,2,4,5-tetrazine, 1 ,2,3,4-tetrazine, 1 ,2,3,5-tetrazine, or condensed groups, such as indole, isoindole, indolizine, indazole, benzimidazole, benzotriazole, purine, naphthimidazole, phenanthrimidazole, pyridimidazole, pyrazinimidazole, quinoxalinimidazole, benzoxazole, naphthoxazole, anthroxazole, phenanthroxazole, isoxazole, benzothiazole, benzofuran, isobenzofuran, dibenzofuran, quinoline, isoquinoline, pteridine, benzo-5,6-quinoline, benzo-6,7-quinoline, benzo-7,8-quinoline, benzoisoquinoline, acridine, phenothiazine, phenoxazine, benzopyridazine, benzopyrimidine, quinoxaline, phenazine, naphthyridine, azacarbazole, benzocarboline, phenanthridine, phenanthroline, thieno[2,3b]thiophene, thieno[3,2b]thiophene, dithienothiophene, isobenzothiophene, dibenzothiophene, benzothiadiazothiophene, or combinations of these groups. The heteroaryl groups may also be substituted by alkyl, alkoxy, thioalkyl, fluorine, fluoroalkyl or further aryl or heteroaryl groups.
The (non-aromatic) alicyclic and heterocyclic groups encompass both saturated rings, i.e. those that contain exclusively single bonds, and partially unsaturated rings, i.e. those that may also contain multiple bonds. Heterocyclic rings contain one or more heteroatoms, preferably selected from Si, O, N, S and Se.
The (non-aromatic) alicyclic and heterocyclic groups can be monocyclic, i.e. contain only one ring (such as, for example, cyclohexane), or polycyclic, i.e. contain a plurality of rings (such as, for example, decahydronaphthalene or bicyclooctane). Preference is given to saturated groups. Preference is furthermore given to mono-, bi-, or tricyclic groups having 3 to 25 C atoms, which optionally contain fused rings and which are optionally substituted. Preference is furthermore given to 5-, 6-, 7- or 8-membered carbocyclic groups in which, in addition, one or more C atoms may be replaced by Si and/or one or more CH groups may be replaced by N and/or one or more non-adjacent CH2 groups may be replaced by -O- and/or -S-.
Preferred alicyclic and heterocyclic groups are, for example, 5-membered groups, such as cyclopentane, tetrahydrofuran, tetrahydrothiofuran, pyrrolidine, 6-membered groups, such as cyclohexane, silinane, cyclohexene, tetrahydropyran, tetrahydrothiopyran, 1 ,3-dioxane, 1 ,3-dithiane, piperidine, 7-membered groups, such as cycloheptane, and fused groups, such as tetrahydronaphthalene, decahydronaphthalene, indane, bicyclo[1 .1 .1 ]pentane-1 ,3-diyl, bicyclo[2.2.2]octane-1 ,4-diyl, spiro[3.3]heptane-2,6-diyl, octahydro-4, 7- methanoindane-2,5-diyl.
The aryl, heteroaryl, (non-aromatic) alicyclic and heterocyclic groups optionally have one or more substituents, which are preferably selected from the group comprising silyl, sulfo, sulfonyl, formyl, amine, imine, nitrile, mercapto, nitro, halogen, C1-C12 alkyl, C6-C12 aryl, C1-C12 alkoxy, hydroxyl, or combinations of these groups.
Preferred substituents are, for example, solubility-promoting groups, such as alkyl or alkoxy, electronwithdrawing groups, such as fluorine, nitro or nitrile, or substituents for increasing the glass transition temperature (Tg) in the polymer, in particular bulky groups, such as, for example, t-butyl or optionally substituted aryl groups.
Preferred substituents, also referred to as "L" below, are, for example, F, Cl, Br, I, -OH, -CN, -NO2, -NCO, -NCS, -OCN, -SCN, -C(=O)N(RX)2, -C(=O)YX, -C(=O)RX, -C(=O)ORX, -N(RX)2, in which Rx has the above-mentioned meaning, and above Yx denotes halogen, optionally substituted silyl, optionally substituted aryl or heteroaryl having 4 to 40, preferably 4 to 20 ring atoms, and straight-chain or branched alkyl, alkenyl, alkinyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, in which one or more H atoms may optionally be replaced by F or Cl.
"Substituted silyl or aryl" preferably means substituted by halogen, -CN, Ry, -OR*, -CO-Ry, -CO-O-Ry, -O-CO- Ry or -O-CO-O-Ry, in which Ry denotes H, a straight-chain, branched or cyclic alkyl chain having 1 to 12 C atoms. In the formula shown above and below, a substituted phenylene ring
Figure imgf000012_0001
in which L has, on each occurrence identically or differently, one of the meanings given above and below, and is preferably F, Cl, CN, NO2, CH3, C2H5, C(CH3)3, CH(CH3)2, CH2CH(CH3)C2H5, OCH3, OC2H5, COCH3, COC2H5, COOCH3, COOC2H5, CF3, OCF3, OCHF2, OC2F5 or P-Sp-, very preferably F, Cl, CN, CH3, C2H5, OCH3, COCH3, OCF3 or P-Sp-, most preferably F, Cl, CH3, OCH3, COCH3 or OCF3.
"Halogen" denotes F, Cl, Br or I, preferably F or Cl, more preferably F.
‘‘Polymerisable groups" (P) are preferably selected from groups containing a C=C double bond or C=C triple bond, and groups which are suitable for polymerisation with ring opening, such as, for example, oxetane or epoxide groups.
Preferably, polymerisable groups (P) are selected from the group consisting of
O w3
Figure imgf000012_0002
in which
W1 denotes H, F, Cl, CN, CF3, phenyl or alkyl having 1 to 5 C atoms, in particular H, F, Cl or CH3,
W2 denotes H or alkyl having 1 to 5 C atoms, in particular H, methyl, ethyl, or n-propyl,
W3 and W4 each, independently of one another, denote H, Cl or alkyl having 1 to 5 C atoms, Phe denotes 1 ,4-phenylene, which is optionally substituted by one or more radicals L as being defined above but being different from P-Sp, preferably preferred substituents L are F, Cl, CN, NO2, CH3, C2H5, OCH3, OC2H5, COCH3, COC2H5, COOCH3, COOC2H5, CF3, OCF3, OCHF2, OC2F5, furthermore phenyl, and ki , k2 and ks each, independently of one another, denote 0 or 1 , ks preferably denotes 1 , and k4 is an integer from 1 to 10.
Particularly preferred polymerizable groups P are CH2=CH-COO-, CH2=C(CH3)-COO-, CH2=CF-COO-,
O 2 ' ' CH2=CH)2CH-OCO-, (CH2=CH)2CH-O-, W HO - CH - and
Figure imgf000013_0001
in which W2 denotes H or alkyl having 1 to 5 C atoms, in particular H, methyl, ethyl or n-propyl,
Further preferred polymerizable groups (P) are vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane and epoxide, most preferably acrylate or methacrylate, in particular acrylate.
Preferably, all multireactive polymerisable compounds and sub-formulae thereof contain instead of one or more radicals P-Sp-, one or more branched radicals containing two or more polymerisable groups P (multireactive polymerisable radicals).
Suitable radicals of this type, and polymerisable compounds containing them, are described, for example, in US 7,060,200 B1 or US 2006/0172090 A1 .
Preference is given to multireactive polymerisable radicals selected from the following formulae:
-X-alkyl-CHPx-CH2-CH2Py l*a
-X-alkyl-C(CH2Px)(CH2Py)-CH2Pz l*b
-X-alkyl-CHPxCHPy-CH2Pz l*c
-X-alkyl-C(CH2Px)(CH2Py)-CaaH2aa+i l*d
-X-alkyl-CHPx-CH2Py l*e
-X-alkyl-CHPxPy l*f
-X-alkyl-CPxPy-CaaH2aa+i l*g
-X-alkyl-C(CH2Pv)(CH2Pw)-CH2OCH2-C(CH2Px)(CH2Py)CH2Pz l*h
-X-alkyl-CH((CH2)aaPx)((CH2)bbPy) l*i -X-alkyl-CHPxCHPy-CaaH2aa+1 l*k in which alkyl denotes a single bond or straight-chain or branched alkylene having 1 to 12 C atoms, in which one or more non-adjacent CH2 groups may each be replaced, independently of one another, by -C(RX)=C(RX)-, -C=C-, -N(RX)-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- in such a way that O and/or S atoms are not linked directly to one another, and in which, in addition, one or more H atoms may be replaced by F, Cl or CN, where Rx has one the above-mentioned meaning, aa and bb each, independently of one another, denote 0, 1 , 2, 3, 4, 5 or 6,
X has one of the meanings indicated for X1, and
Pvto Pz each, independently of one another, have one of the meanings indicated above for P.
Preferred spacer groups Sp are selected from the formula Sp'-X1, so that the radical "P-Sp-" conforms to the formula "P-Sp'-X1-", where
Sp1 denotes alkylene having 1 to 20, preferably 1 to 12 C atoms, which is optionally mono- or polysubstituted by F, Cl, Br, I or CN and in which, in addition, one or more non-adjacent CH2 groups may each be replaced, independently of one another, by -O-, -S-, -NH-, -NRxx-, -SIRXXR»'-, -CO-, -COO-, -OCO-, -OCO-O-, -S-CO-, -CO-S-, -NR^-CO-O-, -O-CO-NR0xx-, -NRxx-CO-NRyy-, -CH=CH- or -C=C- in such a way that O and/or S atoms are not linked directly to one another,
X' denotes -O-, -S-, -CO-, -COO-, -OCO-, -O-COO-, -CO-NR"-,
-NRXX-CO-, -NRxx-CO-NRyy-, -OCH2-, -CH2O-, -SCH2-,
-CH2S-, -CF2O-, -OCF2-, -CF2S-, -SCF2-, -CF2CH2-,
-CH2CF2-, -CF2CF2-, -CH=N-, -N=CH-, -N=N-, -CH=CRXX-,
-CYXX=CYXX-, -C=C-, -CH=CH-COO-, -OCO-CH=CH- or a single bond,
Rxx and Ryy each, independently of one another, denote H or alkyl having 1 to 12 C atoms, and
Yxx and Yyy each, independently of one another, denote H, F, Cl or CN.
X' is preferably -O-, -S- -CO-, -COO-, -OCO-, -O-COO-,
-CO-NRXX-, -NR^-CO-, -NRxx-CO-NRyy- or a single bond.
Typical spacer groups Sp1 are, for example, -(CH2)pi-, -(CH2CH2O)qi-CH2CH2-, -CH2CH2-S-CH2CH2-, - CH2CH2-NH-CH2CH2- or -(SIRxxRyy-O)Pi-, in which p1 is an integer from 1 to 12, q1 is an integer from 1 to 3, and R^ and Ryy have the above-mentioned meanings. Particularly preferred groups -X'-Sp1- are -(CH2)pi-, -O-(CH2)PI-, -OCO-(CH2)PI-, -OCOO-(CH2)PI-, in which p1 is an integer from 1 to 12.
Particularly preferred groups Sp1 are, for example, in each case straight-chain, methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, octadecylene, ethyleneoxyethylene, methyleneoxybutylene, ethylenethioethylene, ethylene-N- methyliminoethylene, 1 -methylalkylene, ethenylene, propenylene and butenylene.
For the present invention,
Figure imgf000015_0001
denote trans-1 ,4-cyclohexylene, and
Figure imgf000015_0002
denote 1 ,4-phenylene.
Figure imgf000015_0003
For the present invention the groups -COO- -C(=O)O- or -CO2- denote an ester group of formula
Figure imgf000015_0004
and the groups -OCO-, -OC(=O)-, -O2C- or -OOC- denote an ester group of formula
All concentrations are quoted in percent by weight (w/w) and relate to the respective mixture as a whole, all temperatures are quoted in degrees Celsius, and all temperature differences are quoted in differential degrees.
Unless the context clearly indicates otherwise, as used herein plural forms of the terms herein are to be construed as including the singular form and vice versa.
Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of the words, for example “comprising” and “comprises”, mean “including but not limited to”, and are not intended to (and do not) exclude other components. On the other hand, the word “comprise” also encompasses the term “consisting of” but is not limited to it.
Throughout the description and claims of this specification, the words “obtainable” and “obtained” and variations of the words, mean “including but not limited to”, and are not intended to (and do not) exclude other components. On the other hand, the word “obtainable” also encompasses the term “obtained” but is not limited to it. Detailed Description of the Invention
In preferred embodiment, one or more of the liquid crystalline polymer films of the optical component is obtainable or obtained from a polymerizable LC medium comprising one or more di- or multireactive RMs which are preferably selected from the group of compounds of formula DRM,
P1-Sp1-MG-Sp2-P2 DRM wherein
P1 and P2 independently of each other denote a polymerisable group,
Sp1 and Sp2 independently of each other are a spacer group or a single bond, and
MG is a rod-shaped mesogenic group, which is preferably selected of formula MG
-(A1-Z1)n-A2- MG wherein
A1 and A2 denote, in case of multiple occurrence independently of one another, an aromatic or alicyclic group, which optionally contains one or more heteroatoms selected from N, O and S, and is optionally mono- or polysubstituted by L,
L is P-Sp-, F, Cl, Br, I, -CN, -NO2 , -NCO, -NCS, -OCN, -SCN, -C(=O)NRxRy, -C(=O)ORX, -C(=O)RX, - NRxRy, -OH, -SF5, optionally substituted silyl, aryl or heteroaryl with 1 to 12, preferably 1 to 6 C atoms, and straight chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 12, preferably 1 to 6 C atoms, wherein one or more H atoms are optionally replaced by F or Cl,
Rx and Ry independently of each other denote H or alkyl with 1 to 12 C-atoms,
Z1 denotes, in case of multiple occurrence independently of one another, -O-, -S-, -CO-, -COO-, - -O-, -O-CO-NR00-, - -CF2CH2-, -CH2CF2-, -
Figure imgf000016_0001
CO-CH=CH- or a single bond, preferably -COO-, -OCO- or a single bond,
Y1 and Y2 independently of each other denote H, F, Cl or CN, n is 1 , 2, 3 or 4, preferably 1 or 2, most preferably 2, n1 is an integer from 1 to 10, preferably 1 , 2, 3 or 4.
Preferred groups A1 and A2 include, without limitation, furan, pyrrol, thiophene, oxazole, thiazole, thiadiazole, imidazole, phenylene, cyclohexylene, bicyclooctylene, cyclohexenylene, pyridine, pyrimidine, pyrazine, azulene, indane, fluorene, naphthalene, tetrahydronaphthalene, anthracene, phenanthrene and dithienothiophene, all of which are unsubstituted or substituted by 1 , 2, 3 or 4 groups L as defined above. Particular preferred groups A1 and A2 are selected from 1 ,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, thiophene-2, 5-diyl, naphthalene-2,6-diyl, 1 ,2,3,4-tetrahydro-naphthalene-2,6-diyl, indane-2,5-diyl, bicyclooctylene or 1 ,4-cyclohexylene wherein one or two non-adjacent CH2 groups are optionally replaced by O and/or S, wherein these groups are unsubstituted or substituted by 1 , 2, 3 or 4 groups L as defined above.
Preferred RMs of formula DRM are selected of formula DRMa
DRMa
Figure imgf000017_0001
wherein
P° is, in case of multiple occurrence independently of one another, a polymerisable group, preferably an acryl, methacryl, oxetane, epoxy, vinyl, heptadiene, vinyloxy, propenyl ether or styrene group,
Z° is each and idependently,-COO-, -OCO-, -CH2CH2-, -CF2O-, -OCF2-, -C=C-, -CH=CH-,-OCO-CH=CH-, - CH=CH-COO-, or a single bond,
L has on each occurrence identically or differently one of the meanings given for L1 in formula I, and is preferably, in case of multiple occurrence independently of one another, selected from F, Cl, CN or optionally halogenated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 5 C atoms, r is 0, 1 , 2, 3 or 4, x and y are independently of each other 0 or identical or different integers from 1 to 12, z is 0 or 1 , with z being 0 if the adjacent x or y is 0.
Very preferred RMs of formula DRM are selected from the following formulae:
Figure imgf000017_0002
Figure imgf000018_0001
wherein P°, L, r, x, y and z are as defined in formula DRMa.
Especially preferred are compounds of formula DRMal , DRMa2 and DRMa3, in particular those of formula DRMal . The concentration of di- or multireactive RMs, preferably those of formula DRM and its subformulae, in the polymerizable LC medium is preferably from 1 % to 60 %, very preferably from 10 to 60%, more preferably 20 to 55%.
In preferred embodiment, the polymerizable LC medium comprises one or more monoreactive RMs additionally to the di- or multireactive RMs that are preferably selected of formula DRM
These additional monoreactive RMs are preferably selected from the group of compounds of formula MRM,
P1-Sp1-MG-R MRM wherein P1, Sp1 and MG have the meanings given in formula DRM,
R denotes, F, Cl, Br, I, -CN, -NO2 , -NCO, -NCS, -OCN, -SCN, -C(=O)NRXR'', -C(=O)X, -C(=O)ORX, - C(=O)R*, -NRxR , -OH, -SF5, optionally substituted silyl, straight chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 12, preferably 1 to 6 C atoms, wherein one or more H atoms are optionally replaced by F or Cl,
X is halogen, preferably F or Cl, and
Rx and Ry are independently of each other H or alkyl with 1 to 12 C-atoms.
Preferably the RMs of formula MRM are selected from the following formulae.
Figure imgf000019_0001
Figure imgf000020_0001
Figure imgf000021_0001
MRM24
Figure imgf000022_0001
wherein P°, L, r, x, y and z are as defined in formula DRMa,
R° is alkyl, alkoxy, thioalkyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 or more, preferably 1 to 15 C atoms or denotes Y° or P-(CH2)y-(O)z-, -OCH2-, -CH2O-, -
-CF2CF2-, -CH=N-, -
Figure imgf000022_0002
single bond,
Y° is F, Cl, CN, NO2, OCH3, OCN, SCN, SFs, or mono- oligo- or polyfluorinated alkyl or alkoxy with 1 to 4 C atoms,
Z° is -COO-, -OCO-, -CH2CH2-, -CF2O-, -OCF2-, -CH=CH-,-OCO-CH=CH-, -CH=CH-COO-, or a single bond,
A0 is, in case of multiple occurrence independently of one another, 1 ,4-phenylene that is unsubstituted or substituted with 1 , 2, 3 or 4 groups L, or trans-1 ,4-cyclohexylene,
R01 02 are independently of each other H, R° or Y°, u and v are independently of each other 0, 1 or 2, w is 0 or 1 , and wherein the benzene and naphthalene rings can additionally be substituted with one or more identical or different groups L.
Especially preferred are compounds of formula MRM1 , MRM2, MRM3, MRM4, MRM5, MRM6, MRM7, in particular those of formula MRM1 , MRM4, MRM6, and MRM7.
The concentration of all monoreactive RMs in the polymerizable LC medium is preferably from 1 to 80%, very preferably from 5 to 70%, more preferably 10 to 60%.
The compounds of the formulae DRM, MRM, and sub-formulae thereof can be pre-pared analogously to processes known to the person skilled in the art and described in standard works of organic chemistry, such as, for example, in Houben-Weyl, Methoden der organischen Chemie [Methods of Organic Chemistry], Thieme-Verlag, Stuttgart.
In a preferred embodiment, the proportion of polymerizable mesogenic compounds in the polymerizable liquid-crystalline medium according to the present invention as a whole, is in the range from 30 to 99 % by weight, more preferably in the range from 40 to 97 % by weight and even more preferably in the range from 50 to 95% by weight.
Preferably, the proportion of said mono-, di- or multireactive liquid-crystalline compounds, preferably selected from the compounds of the formulae DRM, MRM as given above and below in the polymerizable liquidcrystalline medium according to the present invention as a whole, is preferably in the range from 30 to 99.9 % by weight, more preferably in the range from 40 to 99.9 % by weight and even more preferably in the range from 50 to 99.9% by weight.
In a preferred embodiment, the proportion of di- or multireactive polymerizable mesogenic compounds in the polymerizable liquid-crystalline medium according to the present invention as a whole, is preferably in the range from 5 to 99 % by weight, more preferably in the range from 10 to 97 % by weight and even more preferably in the range from 15 to 95% by weight.
In another preferred embodiment, the proportion of monoreactive polymerizable mesogenic compounds in a polymerizable liquid-crystalline medium according to the present invention as a whole, is, if present, preferably in the range from 5 to 80% by weight, more preferably in the range from 10 to 75 % by weight and even more preferably in the range from 15 to 70 % by weight.
In another preferred embodiment, the proportion of multireactive polymerizable mesogenic compounds in a polymerizable liquid-crystalline medium according to the present invention as a whole is, if present, preferably in the range from 1 to 30 % by weight, more preferably in the range from 2 to 20 % by weight and even more preferably in the range from 3 to 10% by weight.
In another preferred embodiment the polymerizable LC medium does not contain polymerizable mesogenic compounds having more than two polymerizable groups.
In another preferred embodiment the polymerizable LC medium does not contain polymerizable mesogenic compounds having less than two polymerizable groups.
In a further preferred embodiment, the polymerizable LC materia comprises one or more monoreactive mesogenic compounds, preferably selected from formulae MRM-10, one or more direactive mesogenic compounds, preferably selected from formula DRMa-1 .
In a further preferred embodiment, the polymerizable LC medium comprises at least two monoreactive mesogenic compounds, preferably selected from compounds of formulae MRM-8 and/or MRM-10, one or more direactive mesogenic compounds, preferably selected from formula DRMa-1 .
In a further preferred embodiment, the polymerizable LC medium comprises at least two monoreactive mesogenic compounds, preferably selected from compounds of formulae MRM-8 and/or MRM-10, at least two direactive mesogenic compounds, preferably selected from compounds of formula DRMa-1 .
In a further preferred embodiment, the polymerizable LC medium comprises at least two direactive mesogenic compounds, preferably selected from compounds of formula DRMa-1 . The polymerizable LC medium suitable for the production of the second or cholesteric polymer film comprises one or more chiral compounds.
Preferably the utilized chiral compounds have each alone or in combination with each other an absolute value of the helical twisting power (HTP) of 20 pm'1 or more, preferably of 40 pm'1 or more, more preferably in the range of 60 pm'1 or more, most preferably in the range of 80 pm'1 or more to 260 pm'1 .
Preferably, non-polymerisable chiral compounds are selected from the group of compounds of formulae C-l to C-lll,
Figure imgf000024_0001
the latter ones including the respective (S,S) enantiomers, wherein E and F are each independently 1 ,4-phenylene or trans-1 ,4-cyclohexylene, v is 0 or 1 , Z° is -COO-, - OCO-, -CH2CH2- or a single bond, and R is alkyl, alkoxy or alkanoyl with 1 to 12 C atoms.
Particularly preferred are chiral compounds, which do not necessarily have to show a liquid crystalline phase.
The compounds of formula C-ll and their synthesis are described in WO 98/00428. Especially preferred is the compound CD-1 , as shown in table D below. The compounds of formula C-lll and their synthesis are described in GB 2 328 207. Further, typically used chiral compounds are e.g. the commercially available R/S-5011 , CD-1 , R/S-811 and CB-15 (from Merck KGaA, Darmstadt, Germany).
The above mentioned chiral compounds R/S-5011 and CD-1 and the (other) compounds of formulae C-l, C-ll and C-lll exhibit a very high helical twisting power (HTP), and are therefore particularly useful for the purpose of the present invention.
The polymerizable LC medium preferably comprises 1 to 5, in particular 1 to 3, very preferably 1 or 2 chiral compounds, preferably selected from the above formula C-ll, in particular CD-1 , and/or formula C-lll and/or R-5011 or S-5011 , very preferably, the chiral compound is R-5011 , S-5011 or CD-1 .
Preferably the polymerizable LC medium comprise one or more non-reactive chiral compound and/or one or more reactive chiral compounds, which are preferably selected from mono- and/or multireactive chiral compounds.
Suitable mesogenic reactive chiral compounds preferably comprise one or more ring elements, linked together by a direct bond or via a linking group and, where two of these ring elements optionally may be linked to each other, either directly or via a linking group, which may be identical to or different from the linking group mentioned. The ring elements are preferably selected from the group of four-, five-, six- or seven-, preferably of five- or six-, membered rings.
Preferred mono-reactive chiral compounds are selected from compounds of formula CRMa to CRMc. b c
Figure imgf000025_0001
wherein
P°* denotes a polymerisable group P
R is alkyl, alkoxy, thioalkyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 or more, preferably 1 to 15 C atoms or P°*-(CH2)o-X2-,
A0 and B° are, in case of multiple occurrence independently of one another, 1 ,4-phenylene that is unsubstituted or substituted with 1 , 2, 3 or 4 groups L as defined above, or trans-1 ,4-cyclohexylene,
X1 and X2 are independently of each other -O-, -COO-, -OCO-, -O-CO-O- or a single bond,
Z°* and Z° are, in case of multiple occurrence independently of one another, -COO-, -OCO-, -O-CO-O-,
-OCH2-, -CH2O-, -CF2O-, -OCF2-, -CH2CH2-, -(CH2)4-, -CF2CH2-, -CH2CF2-, -CF2CF2-, -C=C-, -CH=CH-, -CH=CH-COO-, -OCO-CH=CH- or a single bond,
0 is, independently of each other 0, 1 , 2 or 3, t is 0, 1 or 2,
0 is 0 or an integer from 1 to 12, a and v is 0, 1 , or 2, z is 0 or 1 , and wherein the naphthalene rings can additionally be substituted with one or more identical or different groups L wherein L is, independently of each other F, Cl, CN, halogenated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 5 C atoms.
The compounds of formula CRM are preferably selected from the group of compounds of the following formula
Figure imgf000026_0001
wherein A0, B°, Z0*, P0*, a and b have the meanings given in formula CRM or one of the preferred meanings given above and below, and (OCO) denotes -O-CO- or a single bond, and X2 denotes -O-, -COO-, -OCO-, -O-CO-O- or a single bond.
Especially preferred compounds of formula CRM are selected from the group consisting of the following subformulae:
Figure imgf000027_0001
Figure imgf000028_0001
wherein R is -X2-(CH2)x-P°* as defined in formula CRMa, and the benzene and naphthalene rings are unsubstituted or substituted with 1 , 2, 3 or 4 groups L as defined above and below. In a further preferred embodiment the polymerizable LC medium optionally comprises one or more additives selected from the group consisting of further polymerization initiators, antioxidants, surfactants, stabilisers, catalysts, sensitizers, inhibitors, chain-transfer agents, co-reacting monomers, reactive thinners, surfaceactive compounds, lubricating agents, wetting agents, dispersing agents, hydrophobing agents, adhesive agents, flow improvers, degassing or defoaming agents, deaerators, diluents, reactive diluents, auxiliaries, colourants, dyes, pigments and nanoparticles.
In another preferred embodiment, the polymerizable LC medium optionally comprises one or more additives selected from polymerizable non-mesogenic compounds (reactive thinners). The amount of these additives in the polymerizable LC medium is preferably from 0 to 30 %, very preferably from 0 to 25 %.
The reactive thinners used are not only substances which are referred to in the actual sense as reactive thinners, but also auxiliary compounds already mentioned above which contain one or more complementary reactive units or polymerizable groups P, for example hydroxyl, thiol-, or amino groups, via which a reaction with the polymerizable units of the liquid-crystalline compounds can take place.
The substances, which are usually capable of photopolymerization, include, for example, mono-, bi- and polyfunctional compounds containing at least one olefinic double bond. Examples thereof are vinyl esters of carboxylic acids, for example of lauric, myristic, palmitic and stearic acid, and of dicarboxylic acids, for example of succinic acid, adipic acid, allyl and vinyl ethers and methacrylic and acrylic esters of monofunctional alcohols, for example of lauryl, myristyl, palmityl and stearyl alcohol, and diallyl and divinyl ethers of bifunctional alcohols, for example ethylene glycol and 1 ,4-butanediol.
Also suitable are, for example, methacrylic and acrylic esters of polyfunctional alcohols, in particular those which contain no further functional groups, or at most ether groups, besides the hydroxyl groups. Examples of such alcohols are bifunctional alcohols, such as ethylene glycol, propylene glycol and their more highly condensed representatives, for example diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol etc., butanediol, pentanediol, hexanediol, neopentyl glycol, alkoxylated phenolic compounds, such as ethoxylated and propoxylated bisphenols, cyclohexanedimethanol, trifunctional and polyfunctional alcohols, such as glycerol, trimethylolpropane, butanetriol, trimethylolethane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, sorbitol, mannitol, and the corresponding alkoxylated, in particular ethoxylated and propoxylated alcohols.
Other suitable reactive thinners are polyester (meth)acrylates, which are the (meth)acrylic ester of polyesterols.
Examples of suitable polyesterols are those which can be prepared by esterification of polycarboxylic acids, preferably dicarboxylic acids, using polyols, preferably diols. The starting materials for such hydroxylcontaining polyesters are known to the person skilled in the art. Dicarboxylic acids which can be employed are succinic, glutaric acid, adipic acid, sebacic acid, o-phthalic acid and isomers and hydrogenation products thereof, and esterifiable and transesterifiable derivatives of said acids, for example anhydrides and dialkyl esters. Suitable polyols are the abovementioned alcohols, preferably ethyleneglycol, 1 ,2- and 1 ,3-propylene glycol, 1 ,4-butanediol, 1 ,6-hexanediol, neopentyl glycol, cyclohexanedimethanol and polyglycols of the ethylene glycol and propylene glycol type. Suitable reactive thinners are furthermore 1 ,4-divinylbenzene, triallyl cyanurate, acrylic esters of tricyclodecenyl alcohol also known under the name dihydrodicyclopentadienyl acrylate, and the allyl esters of acrylic acid, methacrylic acid and cyanoacrylic acid.
Of the reactive thinners, which are mentioned by way of example, those containing photopolymerizable groups are used in particular and in view of the abovementioned preferred compositions.
This group includes, for example, dihydric and polyhydric alcohols, for example ethylene glycol, propylene glycol and more highly condensed representatives thereof, for example diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol etc., butanediol, pentanediol, hexanediol, neopentyl glycol, cyclohexanedimethanol, glycerol, trimethylolpropane, butanetriol, trimethylolethane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, sorbitol, mannitol and the corresponding alkoxylated, in particular ethoxylated and propoxylated alcohols.
The group furthermore also includes, for example, alkoxylated phenolic compounds, for example ethoxylated and propoxylated bisphenols.
These reactive thinners may furthermore be, for example, epoxide or urethane (meth)acrylates.
Epoxide (meth)acrylates are, for example, those as obtainable by the reaction, known to the person skilled in the art, of epoxidized olefins or poly- or diglycidyl ether, such as bisphenol A diglycidyl ether, with (meth)acrylic acid.
Urethane (meth)acrylates are, in particular, the products of a reaction, likewise known to the person skilled in the art, of hydroxylalkyl (meth)acrylates with poly- or diisocyanates.
Such epoxide and urethane (meth)acrylates are included amongst the compounds listed above as “mixed forms”.
If reactive thinners are used, their amount and properties must be matched to the respective conditions in such a way that, on the one hand, a satisfactory desired effect, for example the desired colour of the composition according to the invention, is achieved, but, on the other hand, the phase behaviour of the liquidcrystalline composition is not excessively impaired. The low-crosslinking (high-crosslinking) liquid-crystalline compositions can be prepared, for example, using corresponding reactive thinners, which have a relatively low (high) number of reactive units per molecule.
The group of diluents include, for example:
C1-C4-alcohols, for example methanol, ethanol, n-propanol, isopropanol, butanol, isobutanol, sec-butanol and, in particular, the C5-C12-alcohols n-pentanol, n-hexanol, n-heptanol, n-octanol, n-nonanol, n-decanol, n- undecanol and n-dodecanol, and isomers thereof, glycols, for example 1 ,2-ethylene glycol, 1 ,2- and 1 ,3- propylene glycol, 1 ,2-, 2,3- and 1 ,4-butylene glycol, di- and triethylene glycol and di- and tripropylene glycol, ethers, for example methyl tert-butyl ether, 1 ,2-ethylene glycol mono- and dimethyl ether, 1 ,2-ethylene glycol mono- and -diethylether, 3-methoxypropanol, 3-isopropoxypropanol, tetra hydrofuran and dioxane, ketones, for example acetone, methyl ethyl ketone, methyl isobutyl ketone and diacetone alcohol (4-hydroxy-4-methyl- 2-pentanone), C1-C5-alkyl esters, for example methyl acetate, ethyl acetate, propyl acetate, butyl acetate and amyl acetate, aliphatic and aromatic hydrocarbons, for example pentane, hexane, heptane, octane, isooctane, petroleum ether, toluene, xylene, ethylbenzene, tetralin, decalin, dimethylnaphthalene, white spirit, Shellsol® and Solvesso® mineral oils, for example gasoline, kerosine, diesel oil and heating oil, but also natural oils, for example olive oil, soya oil, rapeseed oil, linseed oil and sunflower oil.
It is of course also possible to use mixtures of these diluents in the compositions according to the invention.
So long as there is at least partial miscibility, these diluents can also be mixed with water. Examples of suitable diluents here are C1-C4-alcohols, for example methanol, ethanol, n-propanol, isopropanol, butanol, isobutanol and sec-butanol, glycols, for example 1 ,2-ethylene glycol, 1 ,2- and 1 ,3-propylene glycol, 1 ,2-, 2,3- and 1 ,4-butylene glycol, di- and triethylene glycol, and di- and tripropylene glycol, ethers, for example tetrahydrofuran and dioxane, ketones, for example acetone, methyl ethyl ketone and diacetone alcohol (4- hydroxy-4-methyl-2-pentanone), and C1-C4-alkyl esters, for example methyl, ethyl, propyl and butyl acetate.
The diluents are optionally employed in a proportion of from about 0 to 10.0% by weight, preferably from about 0 to 5.0% by weight, based on the total weight of the polymerizable LC medium.
The antifoams and deaerators (c1 )), lubricants and flow auxiliaries (c2)), thermally curing or radiation-curing auxiliaries (c3)), substrate wetting auxiliaries (c4)), wetting and dispersion auxiliaries (c5)), hydrophobicizing agents (c6)), adhesion promoters (c7)) and auxiliaries for promoting scratch resistance (c8)) cannot strictly be delimited from one another in their action.
For example, lubricants and flow auxiliaries often also act as antifoams and/or deaerators and/or as auxiliaries for improving scratch resistance. Radiation-curing auxiliaries can also act as lubricants and flow auxiliaries and/or deaerators and/or as substrate wetting auxiliaries. In individual cases, some of these auxiliaries can also fulfil the function of an adhesion promoter (c8)).
Corresponding to the above-said, a certain additive can therefore be classified in a number of the groups c1) to c8) described below.
The antifoams in group c1) include silicon-free and silicon-containing polymers. The silicon-containing polymers are, for example, unmodified or modified polydialkylsiloxanes or branched copolymers, comb or block copolymers comprising polydialkylsiloxane and polyether units, the latter being obtainable from ethylene oxide or propylene oxide.
The deaerators in group c1) include, for example, organic polymers, for example polyethers and polyacrylates, dialkylpolysiloxanes, in particular dimethylpolysiloxanes, organically modified polysiloxanes, for example arylalkyl-modified polysiloxanes, and fluorosilicones.
The action of the antifoams is essentially based on preventing foam formation or destroying foam that has already formed. Antifoams essentially work by promoting coalescence of finely divided gas or air bubbles to give larger bubbles in the medium to be deaerated, for example the compositions according to the invention, and thus accelerate escape of the gas (of the air). Since antifoams can frequently also be employed as deaerators and vice versa, these additives have been included together under group c1).
Such auxiliaries are, for example, commercially available from Tego as TEGO® Foamex 800, TEGO® Foamex 805 N, TEGO® Foamex 810, TEGO® Foamex 815 N, TEGO® Foamex 825, TEGO® Foamex 835, TEGO® Foamex 840, TEGO® Foamex 842, TEGO® Foamex 1435, TEGO® Foamex 1488, TEGO® Foamex 1495, TEGO® Foamex 3062, TEGO® Foamex 7447, TEGO® Foamex 8020, TEGO® Foamex 8030, TEGO® Foamex 8050, Tego® Foamex N, TEGO® Foamex K 3, TEGO® Antifoam 2-18, TEGO® Antifoam 2-18, TEGO® Antifoam 2-57, TEGO® Antifoam 2-80, TEGO® Antifoam 2-82, TEGO® Antifoam 2-89, TEGO® Antifoam 2-92, TEGO® Antifoam 14, TEGO® Antifoam 28, TEGO® Antifoam 81 , TEGO® Antifoam D 90, TEGO® Antifoam 93, TEGO® Antifoam 200, TEGO® Antifoam 201 , TEGO® Antifoam 202, TEGO® Antifoam 793, TEGO® Antifoam 1488, TEGO® Antifoam 3062, TEGOPREN® 5803, TEGOPREN® 5852, TEGOPREN® 5863, TEGOPREN® 7008, TEGO® Antifoam 1-60, TEGO® Antifoam 1-62, TEGO® Antifoam 1-85, TEGO® Antifoam 2-67, TEGO® Antifoam WM 20, TEGO® Antifoam 50, TEGO® Antifoam 105, TEGO® Antifoam 730, TEGO® Antifoam MR 1015, TEGO® Antifoam MR 1016, TEGO® Antifoam 1435, TEGO® Antifoam N, TEGO® Antifoam KS 6, TEGO® Antifoam KS 10, TEGO® Antifoam KS 53, TEGO® Antifoam KS 95, TEGO® Antifoam KS 100, TEGO® Antifoam KE 600, TEGO® Antifoam KS 911 , TEGO® Antifoam MR 1000, TEGO® Antifoam KS 1100, Tego® Airex 900, Tego® Airex 910, Tego® Airex 920, Tego® Airex 931 , Tego® Airex 935, Tego® Airex 936, Tego® Airex 944, Tego® Airex 960, Tego® Airex 962, Tego® Airex 970, Tego® Airex 978, Tego® Airex 980 and Tego® Airex 985 , Tego® Airex 990, and from BYK as BYK®-011 , BYK®-019, BYK®-020, BYK®-021 , BYK®-022, BYK®-023, BYK®-024, BYK®-025, BYK®-027, BYK®-031 , BYK®-032, BYK®-033, BYK®-034, BYK®-035, BYK®-036, BYK®-037, BYK®-045, BYK®-051 , BYK®-052, BYK®-053, BYK®-055, BYK®-057, BYK®-065, BYK®-066, BYK®-070, BYK®-080, BYK®-088, BYK®-141 and BYK®-A 530.
The auxiliaries in group c1) are optionally employed in a proportion of from about 0 to 3.0% by weight, preferably from about 0 to 2.0% by weight, based on the total weight of the polymerizable LC medium.
In group c2), the lubricants and flow auxiliaries typically include silicon-free, but also silicon-containing polymers, for example polyacrylates or modifiers, low-molecular-weight polydialkylsiloxanes. The modification consists in some of the alkyl groups having been replaced by a wide variety of organic radicals. These organic radicals are, for example, polyethers, polyesters or even long-chain (fluorinated)alkyl radicals, the former being used the most frequently.
The polyether radicals in the correspondingly modified polysiloxanes are usually built up from ethylene oxide and/or propylene oxide units. Generally, the higher the proportion of these alkylene oxide units in the modified polysiloxane, the more hydrophilic is the resultant product.
Such auxiliaries are, for example, commercially available from Tego as TEGO® Glide 100, TEGO® Glide ZG 400, TEGO® Glide 406, TEGO® Glide 410, TEGO® Glide 411 , TEGO® Glide 415, TEGO® Glide 420, TEGO® Glide 432, TEGO® Glide 435, TEGO® Glide 440, TEGO® Glide 450, TEGO® Glide 466, TEGO® Glide 490, TEGO® Glide 496, TEGO® Glide A116, TEGO® Glide A 115, TEGO® Glide B 1484 (can also be used as antifoam and deaerator), TEGO® Flow ATF2, TEGO® Flow 300, TEGO® Flow 460N, TEGO® Flow 425 and TEGO® Flow ZFS 460. Suitable radiation-curable lubricants and flow auxiliaries, which can also be used to improve the scratch resistance, are the products TEGO® Rad 2100, TEGO® Rad 2200, TEGO® Rad
2200 N, TEGO® Rad 2500, TEGO® Rad 2600, TEGO® Rad 2650, and TEGO® Rad 2700, which are likewise obtainable from TEGO.
Such-auxiliaries are also available, for example, from BYK as BYK®-300 BYK®-306, BYK®-307, BYK®-310, BYK®-320, BYK®-333, BYK®-341 , Byk® 354, Byk®361 , Byk®361 N, BYK®388.
Such-auxiliaries are also available, for example, from 3M as FC4430®.
Such-auxiliaries are also available, for example, from Cytonix as FluorN®561 or FluorN®562.
Such-auxiliaries are also available, for example, from Merck KGaA as Tivida® FL 2300 and Tivida® FL 2500
The auxiliaries in group c2) are optionally employed in a proportion of from about 0 to 3.0% by weight, preferably from about 0 to 2.0% by weight, based on the total weight of the polymerizable LC medium.
In group c3), the radiation-curing auxiliaries include, in particular, polysiloxanes having terminal double bonds which are, for example, a constituent of an acrylate group. Such auxiliaries can be crosslinked by actinic or, for example, electron radiation. These auxiliaries generally combine a number of properties together. In the uncrosslinked state, they can act as antifoams, deaerators, lubricants and flow auxiliaries and/or substrate wetting auxiliaries, while, in the crosslinked state, they increase, in particular, the scratch resistance, for example of coatings or films which can be produced using the compositions according to the invention. The improvement in the gloss properties, for example of precisely those coatings or films, is regarded essentially as a consequence of the action of these auxiliaries as antifoams, deaerators and/or lubricants and flow auxiliaries (in the uncrosslinked state).
Examples of suitable radiation-curing auxiliaries are the products TEGO® Rad 2100, TEGO® Rad 2200, TEGO® Rad 2500, TEGO® Rad 2650 and TEGO® Rad 2700 available from TEGO and the product BYK®- 371 available from BYK.
Thermally curing auxiliaries in group c3) contain, for example, primary OH groups, which are able to react with isocyanate groups, for example of the binder.
Examples of thermally curing auxiliaries, which can be used, are the products BYK®-370, BYK®-373 and BYK®-375 available from BYK.
The auxiliaries in group c3) are optionally employed in a proportion of from about 0 to 5.0% by weight, preferably from about 0 to 3.0% by weight, based on the total weight of the polymerizable LC medium.
The substrate wetting auxiliaries in group c4) serve, in particular, to increase the wettability of the substrate to be printed or coated, for example, by printing inks or coating compositions, for example compositions according to the invention. The generally attendant improvement in the lubricant and flow behaviour of such printing inks or coating compositions has an effect on the appearance of the finished (for example crosslinked) print or coating. A wide variety of such auxiliaries are commercially available, for example from Tego as TEGO® Wet KL 245, TEGO® Wet 250, TEGO® Wet 260, TEGO® Wet 500, TEGO® Wet 505, TEGO® Wet 510, and from BYK as BYK®-306, BYK®-307, BYK®-310, BYK®-333, BYK®-344, BYK®-345, BYK®-346 and Byk®-348.
The auxiliaries in group c4) are optionally employed in a proportion of from about 0 to 3.0% by weight, preferably from about 0 to 1 .5% by weight, based on the total weight of the liquid-crystalline composition.
The wetting and dispersion auxiliaries in group c5) serve, in particular, to prevent the flooding and floating and the sedimentation of pigments and are therefore, if necessary, suitable in particular in pigmented compositions.
These auxiliaries stabilize pigment dispersions essentially through electrostatic repulsion and/or steric hindrance of the pigment particles containing these additives, where, in the latter case, the interaction of the auxiliary with the ambient medium (for example binder) plays a major role.
Since the use of such wetting and dispersion auxiliaries is common practice, for example in the technical area of printing inks and paints, the selection of a suitable auxiliary of this type generally does not present the person skilled in the art with any difficulties, if they are used.
Such wetting and dispersion auxiliaries are commercially available, for example from Tego, as , TEGO® Dispers 630, , TEGO® Dispers 705, TEGO® Dispers 710, TEGO® Dispers 740 W and from BYK as Disperbyk®, Disperbyk®-107, Disperbyk®-108, Disperbyk®-110, Disperbyk®-111 , Disperbyk®-115, Disperbyk®-130, Disperbyk®-160, Disperbyk®-161 , Disperbyk®-162, Disperbyk®-163, Disperbyk®-164, 1 Disperbyk®-165, Disperbyk®-166, Disperbyk®-167, Disperbyk®-170, Disperbyk®-174, Disperbyk®-180, Disperbyk®-181 , Disperbyk®-182, Disperbyk®-183, Disperbyk®-184, Disperbyk®-185, Disperbyk®-190, Anti- Terra®-U, Anti-Terra®-U 80, Anti-Terra®-P, Anti-Terra®-203, Anti-Terra®-204, Anti-Terra®-206, BYK®-151 , BYK®-154, BYK®-155, BYK®-P 104 S, BYK®-P 105, Lactimon®, Lactimon®-WS and Bykumen®.
The amount of the auxiliaries in group c5) used on the mean molecular weight of the auxiliary. In any case, a preliminary experiment is therefore advisable, but this can be accomplished simply by the person skilled in the art.
The hydrophobicizing agents in group c6) can be used to give water-repellent properties to prints or coatings produced, for example, using compositions according to the invention. This prevents or at least greatly suppresses swelling due to water absorption and thus a change in, for example, the optical properties of such prints or coatings. In addition, when the composition is used, for example, as a printing ink in offset printing, water absorption can thereby be prevented or at least greatly reduced.
Such hydrophobicizing agents are commercially available, for example, from Tego as, Tego® Phobe 1000, Tego® Phobe 1000 S, Tego® Phobe 1010, Tego® Phobe 1030, Tego® Phobe 1010, Tego® Phobe 1010, Tego® Phobe 1030, Tego® Phobe 1040, Tego® Phobe 1050, Tego® Phobe 1200, Tego® Phobe 1300, Tego® Phobe 1310 Tego® Phobe 1409, Tego® Phobe 1500 N, Tego® Phobe 1650, Tego® Phobe 1659, Tego® Phobe 6010, Tego® Phobe 6510 and Tego® Phobe 1400. The auxiliaries in group c6) are optionally employed in a proportion of from about 0 to 5.0% by weight, preferably from about 0 to 3.0% by weight, based on the total weight of the polymerizable LC medium.
Further adhesion promoters from group c7) serve to improve the adhesion of two interfaces in contact. It is directly evident from this that essentially the only fraction of the adhesion promoter that is effective is that located at one or the other or at both interfaces. If, for example, it is desired to apply liquid or pasty printing inks, coating compositions or paints to a solid substrate, this generally means that the adhesion promoter must be added directly to the latter or the substrate must be pre-treated with the adhesion promoters (also known as priming), i.e. this substrate is given modified chemical and/or physical surface properties.
If the substrate has previously been primed with a primer, this means that the interfaces in contact are that of the primer on the one hand and of the printing ink or coating composition or paint on the other hand. In this case, not only the adhesion properties between the substrate and the primer, but also between the substrate and the printing ink or coating composition or paint play a part in adhesion of the overall multilayer structure on the substrate.
Adhesion promoters in the broader sense which may be mentioned are also the substrate wetting auxiliaries already listed under group c4), but these generally do not have the same adhesion promotion capacity.
In view of the widely varying physical and chemical natures of substrates and of printing inks, coating compositions and paints intended, for example, for their printing or coating, the multiplicity of adhesion promoter systems is not surprising.
Adhesion promoters based on silanes are, for example, 3-aminopropyltrimethoxysilane, 3- aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, N-aminoethyl-3- aminopropyltrimethoxysilane, N-aminoethyl-3-aminopropylmethyldimethoxysilane, N-methyl-3- aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3- glycidyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane and vinyltrimethoxysilane. These and other silanes are commercially available from Huis, for example under the tradename DYNASILAN®.
Corresponding technical information from the manufacturers of such additives should generally be used or the person skilled in the art can obtain this information in a simple manner through corresponding preliminary experiments.
However, if these additives are to be added as auxiliaries from group c7) to the polymerizable LC mediums according to the invention, their proportion optionally corresponds to from about 0 to 5.0% by weight, based on the total weight of the polymerizable LC medium. These concentration data serve merely as guidance, since the amount and identity of the additive are determined in each individual case by the nature of the substrate and of the printing/coating composition. Corresponding technical information is usually available from the manufacturers of such additives for this case or can be determined in a simple manner by the person skilled in the art through corresponding preliminary experiments. The auxiliaries for improving the scratch resistance in group c8) include, for example, the abovementioned products TEGO® Rad 2100, TEGO® Rad 2200, TEGO® Rad 2500, and TEGO® Rad 2700, which are available from Tego.
For these auxiliaries, the amount data given for group c3) are likewise suitable, i.e. these additives are optionally employed in a proportion of from about 0 to 5.0% by weight, preferably from about 0 to 3.0% by weight, based on the total weight of the liquid-crystalline composition.
Examples that may be mentioned of further light, heat and/or oxidation stabilizers are the following: alkylated monophenols, such as 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert- butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4- methylphenol, 2-(a-methylcyclohexyl)-4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2,4,6- tricyclohexylphenol, 2,6-di-tert-butyl-4-methoxymethylphenol, nonylphenols which have a linear or branched side chain, for example 2,6-dinonyl-4-methylphenol, 2,4-dimethyl-6-(1 '-methylundec-1 '-yl)phenol, 2,4- dimethyl-6-(1 '-methylheptadec-1 '-yl)phenol, 2, 4-dimethyl-6-(1 '-methyltridec- 1 '-yl)phenol and mixtures of these compounds, alkylthiomethylphenols, such as 2,4-dioctylthiomethyl-6-tert-butylphenol, 2,4-dioctylthiomethyl-6- methylphenol, 2,4-dioctylthiomethyl-6-ethylphenol and 2,6-didodecylthiomethyl-4-nonylphenol,
Hydroquinones and alkylated hydroquinones, such as 2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert- butylhydroquinone, 2,5-di-tert-amylhydrocrainone, 2,6-diphenyl-4-octadecyloxyphenol, 2,6-di-tert- butylhydroquinone, 2,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4- hydroxyphenyl stearate and bis(3,5-di-tert-butyl-4-hydroxyphenyl)adipate,
Tocopherols, such as a-tocopherol, p-tocopherol, y-tocopherol, b-tocopherol and mixtures of these compounds, and tocopherol derivatives, such as tocopheryl acetate, succinate, nicotinate and polyoxyethylenesuccinate (“tocofersolate”), hydroxylated diphenyl thioethers, such as 2,2'-thiobis(6-tert-butyl-4-methylphenol), 2,2'-thiobis(4-octylphenol), 4,4'-thiobis(6-tert-butyl-3-methylphenol), 4,4'-thiobis(6-tert-butyl-2-methylphenol), 4,4'-thiobis(3,6-di-sec- amylphenol) and 4,4'-bis(2,6-dimethyl-4-hydroxyphenyl)disulfide,
Alkylidenebisphenols, such as 2,2'-methylenebis(6-tert-butyl-4-methylphenol), 2,2'-methylenebis(6-tert-butyl- 4-ethylphenol), 2,2'-methylenebis[4-methyl-6-(a-methylcyclohexyl)phenol], 2,2'-methylenebis(4-methyl-6- cyclohexylphenol), 2,2'-methylenebis(6-nonyl-4-methylphenol), 2,2'-methylenebis(4,6-di-tert-butylphenol), 2,2- ethylidenebis(4,6-di-tert-butylphenol), 2,2'-ethylidenebis(6-tert-butyl-4-isobutylphenol), 2,2'-methylenebis[6-(a- methylbenzyl)-4-nonylphenol], 2,2'-methylenebis[6-(a,a-dimethylbenzyl)-4-nonylphenol], 4,4'- methylenebis(2,6-di-tert-butylphenol), 4,4'-methylenebis(6-tert-butyl-2-methylphenol), 1 ,1 -bis(5-tert-butyl-4- hydroxy-2-methylphenyl)butane, 2,6-bis(3-tert-butyl-5-methyl-2-hydroxybenzyl)-4-methylphenol, 1 ,1 ,3-tris(5- tert-butyl-4-hydroxy-2-methylphenyl)butane, 1 ,1 -bis(5-tert-butyl-4-hydroxy-2-methylphenyl)-3-n-dodecyl- mercaptobutane, ethylene glycol bis[3,3-bis(3'-tert-butyl-4'-hydroxyphenyl)butyrate], bis(3-tert-butyl-4- hydroxy-5-methylphenyl)dicyclopentadiene, bis[2-(3'-tert-butyl-2'-hydroxy-5'-methylbenzyl)-6-tert-butyl-4- methylphenyl]terephthalate, 1 ,1 -bis(3,5-dimethyl-2-hydroxyphenyl)butane, 2,2-bis(3,5-di-tert-butyl-4- hydroxyphenyl)propane, 2,2-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)-4-n-dodecyl-mercaptobutane and 1 ,1 ,5,5-tetrakis(5-tert-butyl-4-hydroxy-2-methylphenyl)pentane,
O-, N- and S-benzyl compounds, such as 3,5,3',5'-tetra-tert-butyl-4,4'-dihydroxydibenzyl ether, octadecyl 4- hydroxy-3,5-dimethylbenzylmercaptoacetate, tridecyl 4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate, tris(3,5-di-tert-butyl-4-hydroxybenzyl)amine, bis(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)dithioterephthalate, bis(3,5-di-tert-butyl-4-hydroxybenzyl)sulfide and isooctyl-3,5-di-tert-butyl-4-hydroxybenzylmercaptoacetate, aromatic hydroxybenzyl compounds, such as 1 ,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethyl- benzene, 1 ,4-bis(3,5-di-tert-butyl-4-hydroxybenzyl)-2,3,5,6-tetramethyl-benzene and 2,4,6-tris(3,5-di-tert- butyl-4-hydroxybenzyl)phenol,
Triazine compounds, such as 2,4-bis(octylmercapto)-6-(3,5-di-tert-butyl-4-hydroxyanilino)-1 ,3,5-triazine, 2- octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyanilino)-1 ,3,5-triazine, 2-octylmercapto-4,6-bis(3,5-di-tert- butyl-4-hydroxyphenoxy)-1 ,3,5-triazine, 2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenoxy)-1 ,2,3-triazine, 1 ,3,5- tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1 ,3,5-tris(4-tert-butyl-3-hydroxy-2,6- dimethylbenzyl)isocyanurate, 2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenylethyl)-1 ,3,5-triazine, 1 , 3 ,5-tris-(3 ,5-d i- tert-butyl-4-hydroxyphenylpropionyl)hexahydro-1 ,3,5-triazine, 1 ,3,5-tris(3,5-dicyclohexyl-4- hydroxybenzyl)isocyanurate and 1 ,3,5-tris(2-hydroxyethyl)isocyanurate,
Benzylphosphonates, such as dimethyl 2,5-di-tert-butyl-4-hydroxybenzylphosphonate, diethyl 3,5-di-tert-butyl- 4-hydroxybenzylphosphonate, dioctadecyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate and dioctadecyl 5- tert-butyl-4-hydroxy-3-methylbenzylphosphonate,
Acylaminophenols, such as 4-hydroxylauroylanilide, 4-hydroxystearoylanilide and octyl N-(3,5-di-tert-butyl-4- hydroxyphenyl)carbamate,
Propionic and acetic esters, for example of monohydric or polyhydric alcohols, such as methanol, ethanol, n- octanol, i-octanol, octadecanol, 1 ,6-hexanediol, 1 ,9-nonanediol, ethylene glycol, 1 ,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N'-bis(hydroxyethyl)oxalamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane and 4-hydroxymethyl-1 -phospha-2,6,7-trioxabicyclo[2.2.2]-octane,
Propionamides based on amine derivatives, such as N,N'-bis(3,5-di-tert-butyl-4- hydroxyphenylpropionyl)hexamethylenediamine, N,N'-bis(3,5-di-tert-butyl-4- hydroxyphenylpropionyl)trimethylenediamine and N,N'-bis(3,5-di-tert-butyl-4- hydroxyphenylpropionyl)hydrazine,
Ascorbic acid (Vitamin C) and ascorbic acid derivatives, such as ascorbyl palmitate, laurate and stearate, and ascorbyl sulfate and phosphate,
Antioxidants based on amine compounds, such as N,N'-diisopropyl-p-phenylenediamine, N,N'-di-sec-butyl-p- phenylenediamine, N,N'-bis(1 ,4-dimethylpentyl)-p-phenylenediamine, N,N'-bis(1-ethyl-3-methylpentyl)-p- phenylenediamine, N,N'-bis(1-methylheptyl)-p-phenylenediamine, N,N'-dicyclohexyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamine, N,N'-bis(2-naphthyl)-p-phenylenediamine, N-isopropyl-N'-phenyl-p- phenylenediamine, N-(1 ,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, N-(1 -methylheptyl)-N'-phenyl-p- phenylenediamine, N-cyclohexyl-N'-phenyl-p-phenylenediamine, 4-(p-toluenesulfamoyl)diphenylamine, N,N'- dimethyl-N,N'-di-sec-butyl-p-phenylenediamine, diphenylamine, N-allyldiphenylamine, 4- isopropoxydiphenylamine, N-phenyl-1 -naphthylamine, N-(4-tert-octylphenyl)-1 -naphthylamine, N-phenyl-2- naphthylamine, octyl-substituted diphenylamine, such as p,p'-di-tert-octyldiphenylamine, 4-n- butylaminophenol, 4-butyrylaminophenol, 4-nonanoylaminophenol, 4-dodecanoylaminophenol, 4- octadecanoylaminophenol, bis[4-methoxyphenyl)amine, 2,6-di-tert-butyl-4-dimethylaminomethylphenol, 2,4- diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, N,N,N',N'-tetramethyl-4,4'-diaminodiphenylmethane, 1 ,2-bis[(2-methylphenyl)amino]ethane, 1 ,2-bis(phenylamino)propane, (o-toly l)big uan ide , bis[4-(1 ',3'- dimethylbutyl)phenyl]amine, tert-octyl-substituted N-phenyl-1 -naphthylamine, a mixture of mono- and dialkylated tert-butyl/tert-octyldiphenylamine, a mixture of mono- and dialkylated nonyldiphenylamine, a mixture of mono- and dialkylated dodecyldiphenylamine, a mixture of mono- and dialkylated isopropyl/isohexyldiphenylamine, a mixture of mono- and dialkylated tert-butyldiphenylamine, 2, 3-d I hydro-3, 3- dimethyl-4H-1 ,4-benzothiazine, phenothiazine, a mixture of mono- and dialkylated tert-butyl/tert- octylphenothiazine, a mixture of mono- and dialkylated tert-octylphenothiazine, N-allylphenothiazine, N,N,N',N'-tetraphenyl-1 ,4-diaminobut-2-ene, N,N-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine, bis(2,2,6,6-tetramethylpiperidin-4-yl)sebacate, 2,2,6,6-tetramethylpiperidin-4-one and 2, 2,6,6- tetramethylpiperidin-4-ol,
Phosphines, Phosphites and phosphonites, such as triphenylphosnine triphenylphosphite, diphenyl alkyl phosphite, phenyl dialkyl phosphite, tris(nonylphenyl)phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl)phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4- methylphenyl)pentaerythritol diphosphite, diisodecyloxy pentaerythritol diphosphite, bis(2,4-di-tert-butyl-6- methylphenyl)pentaerythritol diphosphite, bis(2,4,6-tris(tert-butylphenyl))pentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis(2,4-di-tert-butylphenyl)4,4'-biphenylenediphosphonite, 6-isooctyloxy-2,4,8,10- tetra-tert-butyl-12H-dibenz[d,g]-1 ,3,2-dioxaphosphocine, 6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl- dibenz[d,g]-1 ,3,2-dioxaphosphocine, bis(2,4-di-tert-butyl-6-methylphenyl)methyl phosphite and bis(2,4-di-tert- butyl-6-methylphenyl)ethyl phosphite,
2-(2'-Hydroxyphenyl)benzotriazoles, such as 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(3',5'-di-tert- butyl-2'-hydroxyphenyl)benzotriazole, 2-(5'-tert-butyl-2'-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'- (1 ,1 ,3,3-tetramethylbutyl)phenyl)benzotriazole, 2-(3',5'-di-tert-butyl-2'-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3'-tert-butyl-2'-hydroxy-5'-methylphenyl)-5-chlorobenzotriazole, 2-(3'-sec-butyl-5'-tert-butyl-2'- hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-4'-octyloxyphenyl)benzotriazole, 2-(3',5'-di-tert-amyl-2'- hydroxyphenyl)benzotriazole, 2-(3,5'-bis-(a,a-dimethylbenzyl)-2'-hydroxyphenyl)benzotriazole, a mixture of 2- (3'-tert-butyl-2'-hydroxy-5'-(2-octyloxycarbonylethyl)phenyl)-5-chlorobenzotriazole, 2-(3'-tert-butyl-5'-[2-(2- ethylhexyloxy)carbonylethyl]-2'-hydroxy phenyl)-5-chlorobenzotriazole, 2-(3'-tert-butyl-2'-hydroxy-5'-(2- methoxycarbonylethyl)phenyl)-5-chlorobenzotriazole, 2-(3'-tert-butyl-2'-hydroxy-5'-(2- methoxycarbonylethyl)phenyl)benzotriazole, 2-(3'-tert-butyl-2'-hydroxy-5'-(2- octyloxycarbonylethyl)phenyl)benzotriazole, 2-(3'-tert-butyl-5'-[2-(2-ethylhexyloxy)carbonylethyl]-2'-hydroxy phenyl)benzotriazole, 2-(3'-dodecyl-2'-hydroxy-5'-methylphenyl)benzotriazole and 2-(3'-tert-butyl-2'-hydroxy- 5'-(2-isooctyloxycarbonylethyl)phenyl benzotriazole, 2,2'-methylenebis[4-(1 ,1 ,3,3-tetramethylbutyl)-6- benzotriazol-2-ylphenol]; the product of complete esterification of 2-[3'-tert-butyl-5'-(2-methoxycarbonylethyl)- 2'-hydroxyphenyl]-2H-benzotriazole with polyethylene glycol 300; sulfur-containing peroxide scavengers and sulfur-containing antioxidants, such as esters of 3,3'- thiodipropionic acid, for example the lauryl, stearyl, myristyl and tridecyl esters, mercaptobenzimidazole and the zinc salt of 2-mercaptobenzimidazole, dibutylzinc dithiocarbamates, dioctadecyl disulfide and pentaerythritol tetrakis(P-dodecylmercapto)propionate,
2-hydroxybenzophenones, such as the 4-hydroxy, 4-methoxy, 4-octyloxy, 4-decycloxy, 4-dodecyloxy, 4- benzyloxy, 4,2',4'-trihydroxy and 2'-hydroxy-4,4'-dimethoxy derivatives,
Esters of unsubstituted and substituted benzoic acids, such as 4-tert-butylphenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoylresorcinol, bis(4-tert-butylbenzoyl)resorcinol, benzoylresorcinol, 2,4-di-tert- butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl-3, 5-di-tert-butyl-4-hydroxybenzoate, octadecyl-
3.5-di-tert-butyl-4-hydroxybenzoate and 2-methyl-4,6-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate,
Acrylates, such as ethyl a-cyano-p,[3-diphenylacrylate, isooctyl a-cyano-p,[3-diphenylacrylate, methyl a- methoxycarbonylcinnamate, methyl a-cyano-p-methyl-p-methoxycinnamate, butyl-a-cyano-p-methyl-p- methoxycinnamate and methyl-a-methoxycarbonyl-p-methoxycinnamate, sterically hindered amines, such as bis(2,2,6,6-tetramethylpiperidin-4-yl)sebacate, bis(2,2,6,6-tetramethylpiperidin-4-yl)succinate, bis(1 , 2, 2,6,6- pentamethylpiperidin-4-yl)sebacate, bis(1 -octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)sebacate, bis(1 , 2, 2,6,6- pentamethylpiperidin-4-yl)-n-butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate, the condensation product of 1 - (2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid, the condensation product of N,N'- bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1 ,3,5-triazine, tris(2,2,6,6-tetramethylpiperidin-4-yl)nitrilotriacetate, tetrakis(2,2,6,6-tetramethylpiperidin-4-yl)1 ,2,3,4- butanetetracarboxylate, 1 ,1 '-(1 ,2-ethylene)bis(3,3,5,5-tetramethylpiperazinone), 4-benzoyl-2, 2,6,6- tetramethylpiperidine, 4-stearyloxy-2,2,6,6-tetramethylpiperidine, bis(1 , 2,2,6, 6-pentamethylpiperidin-4-yl)2-n- butyl-2-(2-hydroxy-3,5-di-tert-butylbenzyl)malonate, 3-n-octyl-7,7,9,9-tetramethyl-1 ,3,8- triazaspiro[4.5]decane-2, 4-dione, bis(1 -octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)sebacate, bis(1 -octyloxy-
2.2.6.6-tetramethylpiperidin-4-yl)succinate, the condensation product of N,N'-bis(2,2,6,6-tetramethylpiperidin- 4-yl)hexamethylenediamine and 4-morpholino-2,6-dichloro-1 ,3,5-triazine, the condensation product of 2- chloro-4,6-bis(4-n-butylamino-2,2,6,6-tetramethylpiperidin-4-yl)-1 ,3,5-triazine and 1 ,2-bis(3- aminopropylamino)ethane, the condensation product of 2-chloro-4,6-di(4-n-butylamino-1 , 2, 2,6,6- pentamethylpiperidin-4-yl)-1 ,3,5-triazine and 1 ,2-bis(3-aminopropylamino)ethane, 8-acetyl-3-dodecyl-7, 7,9,9- tetramethyl-1 , 3, 8-triazaspiro[4.5]-decane-2, 4-dione, 3-dodecyl-1 -(2,2,6, 6-tetramethylpiperidin-4-yl)pyrrolidine-
2.5-dione, 3-dodecyl-1 -(1 ,2,2,6, 6-pentamethylpiperidin-4-yl)pyrrolidine-2, 5-dione, a mixture of 4- hexadecyloxy- and 4-stearyloxy-2,2,6,6-tetramethylpiperidine, the condensation product of N, N'-bis(2, 2,6,6- tetramethylpiperidin-4-yl)hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-1 ,3,5-triazine, the condensation product of 1 ,2-bis(3-aminopropylamino)ethane and 2,4,6-trichloro-1 ,3,5-triazine, 4-butylamino-
2.2.6.6-tetramethylpiperidine, N-(2,2,6,6-tetramethylpiperidin-4-yl)-n-dodecylsuccinimide, N-(1 , 2, 2,6,6- pentamethylpiperidin-4-yl)-n-dodecylsuccinimide, 2-undecyl-7,7,9,9-tetramethyl-1 -oxa-3,8-diaza-4-oxo- spiro[4.5]-decane, the condensation product of 7,7,9, 9-tetramethyl-2-cycloundecyl-1 -oxa-3,8-diaza-4- oxospiro-[4.5]decane and epichlorohydrin, the condensation products of 4-amino-2,2,6,6- tetramethylpiperidine with tetramethylolacetylenediureas and poly(methoxypropyl-3-oxy)-[4(2, 2,6,6- tetramethyl)piperidinyl]-siloxane,
Oxalamides, such as 4,4'-dioctyloxyoxanilide, 2,2'-diethoxyoxanilide, 2,2'-dioctyloxy-5,5'-di-tert-butoxanilide, 2,2'-didodecyloxy-5,5'-di-tert-butoxanilide, 2-ethoxy-2'-ethyloxanilide, N,N'-bis(3- dimethylaminopropyl)oxalamide, 2-ethoxy-5-tert-butyl-2'-ethoxanilide and its mixture with 2-ethoxy-2'-ethyl- 5,4'-di-tert-butoxanilide, and mixtures of ortho-, para-methoxy-disubstituted oxanilides and mixtures of ortho- and para-ethoxy-disubstituted oxanilides, and
2-(2-hydroxyphenyl)-1 ,3,5-triazines, such as 2,4,6-tris-(2-hydroxy-4-octyloxyphenyl)-1 ,3,5-triazine, 2-(2- hydroxy-4-octyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1 ,3,5-triazine, 2-(2,4-dihydroxyphenyl)-4,6-bis(2,4- dimethylphenyl)-1 ,3,5-triazine, 2,4-bis(2-hydroxy-4-propyloxyphenyl)-6-(2,4-dimethylphenyl)-1 ,3,5-triazine, 2- (2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl)-1 ,3,5-triazine, 2-(2-hydroxy-4-dodecyloxyphenyl)-4,6- bis(2,4-dimethylphenyl)-1 ,3,5-triazine, 2-(2-hydroxy-4-tridecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1 ,3,5- triazine, 2-[2-hydroxy-4-(2-hydroxy-3-butyloxypropoxy)phenyl]-4,6-bis(2,4-dimethyl)-1 ,3,5-triazine, 2-[2- hydroxy-4-(2-hydroxy-3-octyloxypropoxy)phenyl]-4,6-bis(2,4-dimethyl)-1 ,3,5-triazine, 2-[4- (dodecyloxy/tridecyloxy-2-hydroxypropoxy)-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1 ,3,5-triazine, 2-[2- hydroxy-4-(2-hydroxy-3-dodecyloxypropoxy)phenyl]-4,6-bis-(2,4-dimethylphenyl)-1 ,3,5-triazine, 2-(2-hydroxy- 4-hexyloxyphenyl)-4,6-diphenyl-1 ,3,5-triazine, 2-(2-hydroxy-4-methoxyphenyl)-4,6-diphenyl-1 ,3,5-triazine, 2,4,6-tris[2-hydroxy-4-(3-butoxy-2-hydroxypropoxy)phenyl]-1 ,3,5-triazine and 2-(2-hydroxyphenyl)-4-(4- methoxyphenyl)-6-phenyl-1 ,3,5-triazine.
In another preferred embodiment the polymerizable LC medium comprises one or more specific antioxidant additives, preferably selected from the Irganox® series, e.g. the commercially available antioxidants lrganox®1076 and lrganox®1010, from Ciba, Switzerland.
In another preferred embodiment, the polymerizable LC medium comprises one or more, more preferably two or more photoinitiators, for example, selected from the commercially available Irgacure® or Darocure® (Ciba AG) series, in particular, Irgacure 127, Irgacure 184, Irgacure 369, Irgacure 651 , Irgacure 817, Irgacure 907, Irgacure 1300, Irgacure, Irgacure 2022, Irgacure 2100, Irgacure 2959, or Darcure TPO. Especially the polymerizable LC medium comprises preferably one or more oxime ester photoinitiators preferably selected from the commercially available OXE02 (Ciba AG), NCI 930, N1919T (Adeka), SPI-03 or SPI-04 (Samyang).
The concentration of the polymerization initiator(s) as a whole in the polymerizable LC medium is preferably from 0.5 to 10%, very preferably from 0.8 to 8%, more preferably 1 to 6%.
Preferably, the polymerizable LC medium comprises a given ratio between the concentration of the photoinitiator and the concentration of all chiral compounds as a whole, which is in the range from 1 :1 to 1 :5, more preferably in the range from 1 :1 to 1 :4, even more preferably in the range from 1 :1 to 1 :3.
In a preferred embodiment the polymerizable LC medium is dissolved in a suitable solvent, which are preferably selected from organic solvents. The solvents are preferably selected from ketones such as acetone, methyl ethyl ketone, methyl propyl ketone, methyl isobutyl ketone or cyclohexanone; acetates such as methyl, ethyl or butyl acetate or methyl acetoacetate; alcohols such as methanol, ethanol or isopropyl alcohol; aromatic solvents such as toluene or xylene; alicyclic hydrocarbons such as cyclopentane or cyclohexane; halogenated hydrocarbons such as di- or trichloromethane; glycols or their esters such as PGMEA (propyl glycol monomethyl ether acetate), □- butyrolactone. It is also possible to use binary, ternary or higher mixtures of the above solvents.
In case the polymerizable LC medium contains one or more solvents, the total concentration of all solids, including the RMs, in the solvent(s) is preferably from 10 to 60%.
Preferably, the polymerizable LC medium comprises, a) one or more di- or multireactive polymerizable mesogenic compounds, b) optionally one or more monoreactive polymerizable mesogenic compounds, preferably selected from compounds of formula MRM 8, MRM9 and/or MRM10 and their corresponding subformulae, c) in case of the cholesteric polymer film, one or more chiral mesogenic compounds, preferably selected from compounds of formula CRA or CRB, more preferably of CRB and its subformulae, d) optionally one or more antioxidative additives, e) optionally one or more adhesion promotors, f) optionally one or more surfactants, g) optionally one or more mono-, di- or multireactive polymerizable non-mesogenic compounds, h) optionally one or more dyes showing an absorption maximum at the wavelength used to initiate photo polymerization,
I) optionally one or more chain transfer agents, j) optionally one or more further stabilizers, k) optionally one or more lubricants and flow auxiliaries, and l) optionally one or more diluents, m) optionally a non-polymerizable nematic component, n) optionally one or more organic solvents.
Alternatively, the polymerizable LC medium comprises, a) one or more di- or multireactive polymerizable mesogenic compounds, b) optionally one or more monoreactive polymerizable mesogenic compounds, preferably selected from compounds of formula MRM 8, MRM9 and/or MRM10 and their corresponding subformulae, c) in case of the cholesteric polymer film, one or more chiral mesogenic compounds, preferably selected from compounds of formula CRA or CRB, more preferably of CRB and its subformulae, d) optionally one or more antioxidative additives, e) optionally one or more adhesion promotors, f) optionally one or more surfactants, g) optionally one or more mono-, di- or multireactive polymerizable non-mesogenic compounds, h) optionally one or more dyes showing an absorption maximum at the wavelength used to initiate photo polymerization,
I) optionally one or more chain transfer agents, j) optionally one or more further stabilizers, k) optionally one or more lubricants and flow auxiliaries, and l) optionally one or more diluents, m) optionally a non-polymerizable nematic component, n) optionally one or more organic solvents.
The optical component is typically prepared by a method comprising the steps of
- providing a layer of a polymerizable LC medium as described above and below onto a substrate, which is optionally provided with an alignment layer capable of inducing a planar alignment to the adjacent layer of a polymerizable LC medium,
- irradiation of the layer stack with actinic radiation light,
- providing a layer of a cholesteric polymerizable LC medium as described above and below onto a substrate
- irradiation of the layer stack with actinic radiation,
- optionally removing the layer stack or optical component from the substrate.
The coating order of the above described layers is not important for the optical effects to be achieved, however the light input direction into the optical component is a factor that has to be considered while applying the optical component to the optical or electrooptical device.
Typically the polymerizable LC medium can be coated or printed onto the substrate, for example by spincoating, printing, or other known techniques, and the solvent is evaporated off before polymerization. In most cases, it is suitable to heat the mixture in order to facilitate the evaporation of the solvent.
The polymerizable LC medium can be applied onto a substrate by conventional coating techniques like spin coating, bar coating or blade coating. It can also be applied to the substrate by conventional printing techniques which are known to the expert, like for example screen printing, offset printing, reel-to-reel printing, letter press printing, gravure printing, rotogravure printing, flexographic printing, intaglio printing, pad printing, heat-seal printing, ink-jet printing or printing by means of a stamp or printing plate.
Suitable substrate mediums and substrates are known to the expert and described in the literature, as for example conventional substrates used in the optical films industry, such as glass or plastic. Especially suitable and preferred substrates for polymerization are polyester such as polyethyleneterephthalate (PET) or polyethylenenaphthalate (PEN), polyvinylalcohol (PVA), polycarbonate (PC) triacetylcellulose (TAC), or cyclo olefin polymers (COP), or commonly known color filter materials, in particular triacetylcellulose (TAC), cyclo olefin polymers (COP), or commonly known colour filter materials.
The Friedel-Creagh-Kmetz rule can be used to predict whether a mixture will adopt planar or homeotropic alignment, by comparing the surface energies of the RM layer (YRM) and the substrate (ys):
If YRM > ys the reactive mesogenic compounds will display homeotropic alignment, If YRM < ys the reactive mesogenic compounds will display homogeneous alignment.
Without to be bound by theory, when the surface energy of a substrate is relatively low, the intermolecular forces between the reactive mesogens are stronger than the forces across the RM-substrate interface and consequently, reactive mesogens align perpendicular to the substrate (homeotropic alignment) in order to maximise the intermolecular forces. Accordingly, an additional alignment layer capable of inducing a planar alignment to the adjacent polymerisable LC medium is required.
When the surface tension of the substrate is greater than the surface tension of the RMs, the force across the interface dominates. The interface energy is minimised if the reactive mesogens align parallel with the substrate, so the long axis of the RM can interact with the substrate. One way planar alignment can be promoted is by coating the substrate with a polyimide layer, and then rubbing the alignment layer with a velvet cloth. Other suitable planar alignment layers are known in the art, like for example rubbed polyimide or alignment layers prepared by photoalignment as described in US 5,602,661 , US 5,389,698 or US 6,717,644.
In general, reviews of alignment techniques are given for example by I. Sage in "Thermotropic Liquid Crystals", edited by G. W. Gray, John Wiley & Sons, 1987, pages 75-77; and by T. Uchida and H. Seki in "Liquid Crystals - Applications and Uses Vol. 3", edited by B. Bahadur, World Scientific Publishing, Singapore 1992, pages 1-63. A further review of alignment materials and techniques is given by J. Cognard, Mol. Cryst. Liq. Cryst. 78, Supplement 1 (1981), pages 1-77.
In a preferred embodiment, the process according to the invention contains a process step where the polymerisable LC medium either for the first or for the second polymer film or even both polymer films is allowed to rest for a period of time in order to evenly redistribute the polymerisable LC medium on the substrate or the first polymer film (herein referred to as “annealing").
In a preferred embodiment, after providing the polymerisable LC medium onto the substrate or the first polymer film, the layer stack is annealed for a time between 10 seconds and 1 hour, preferably between 20 seconds and 10 minutes and most preferably between 30 seconds and 2 minutes. The annealing is preferably performed at room temperature.
In an alternative embodiment, the annealing is performed at elevated temperature, preferably above 20°C and below 120°C, more preferably above 40°C and below 100°C and most preferably above 50°C and below 80°C.
In a preferred embodiment, the layer stack is cooled down to room temperature after annealing at an elevated temperature. The cooling can be perfomed actively with the help of cooling aids or passively just by letting the layer stack rest for a given time.
In a preferred embodiment, in the 1 st UV step the polymerizable LC medium is exposed to actinic radiation as described for example in WO 01/20394, GB 2,315,072 or WO 98/04651 .
Actinic radiation means irradiation with light, like UV light, IR light or visible light, irradiation with X-rays or gamma rays, or irradiation with high-energy particles, such as ions or electrons. Preferably, the 1 st UV step is carried out by photo irradiation, in particular with UV light, especially with UVA light.
As a source for actinic radiation, for example a single UV lamp or a set of UV lamps can be used. When using a high lamp power the curing time can be reduced. Another possible source for photo radiation is a laser, like e.g. a UV laser, an IR laser, or a visible laser. The curing time in each step is each and idependently, dependent, inter alia, on the reactivity of the photoreactive compounds, the thickness of the coated layer, and the power and selected wavelength of the UV lamp. The curing time is preferably < 5 minutes, very preferably < 3 minutes, most preferably < 1 minute. For mass production, short curing times of < 30 seconds are preferred.
A suitable UV radiation power in each step is each and idependently and preferably in the range from 5 to 300 mWcm-2, more preferably in the range from 50 to 250 mWcnr2 and most preferably in the range from 100 to 180 mWcirr2.
In connection with the applied UV radiation and as a function of time, a suitable UV dose in each step is each and idependently is preferably in the range from 20 to 1000 mJcm'2 more preferably in the range from 40 to 800 mJcm'2 and most preferably in the range from 40 to 500 mJcnr2.
The curing in each step is each and idependently and preferably performed in air.However it is likewise preferably that the curing step is performed under an inert gas atmosphere, such as preferably nitrogen.
The curing in each step is each and idependently and preferably performed at a temperature from 1 to 70°C, more preferably 5 to 50°C, even more preferably 15 to 30°C, most preferably at room temperature..
The preferred thickness of each polymerized LC film according to the present invention is determined by the optical properties desired from the film or the final product.
For optical applications each of the polymer films have typically a thickness of from 0.5 to 10 pm, very preferably from 0.5 to 5 pm, in particular from 0.5 to 3 pm.
After photopolymerisation, the resulting layer stack of polymer films or the final optical component can be removed from the substrate and combined with other substrates or further optical films by a laminating process known by the skilled person. Suitable substrates and optical films are given above and include especially polarisers.
The optical component according to the present invention can be used in displays of the transmissive or reflective type, especially they can be used in conventional OLED displays or LCDs, in particular OLED displays.
The present invention is described above and below with particular reference to the preferred embodiments. It should be understood that various changes and modifications might be made therein without departing from the spirit and scope of the invention.
Many of the compounds or mixtures thereof mentioned above and below are commercially available. All of these compounds are either known or can be prepared by methods which are known per se, as described in the literature (for example in the standard works such as Houben-Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart), to be precise under reaction conditions which are known and suitable for said reactions. Use may also be made here of variants which are known per se, but are not mentioned here.
It will be appreciated that variations to the foregoing embodiments of the invention can be made while still falling within the scope of the invention. Alternative features serving the same, equivalent, or similar purpose may replace each feature disclosed in this specification, unless stated otherwise. Thus, unless stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.
All of the features disclosed in this specification may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. In particular, the preferred features of the invention are applicable to all aspects of the invention and may be used in any combination. Likewise, features described in non-essential combinations may be used separately (not in combination).
It will be appreciated that many of the features described above, particularly of the preferred embodiments, are inventive in their own right and not just as part of an embodiment of the present invention. Independent protection may be sought for these features in addition to or alternative to any invention presently claimed.
The invention will now be described in more detail by reference to the following working examples, which are illustrative only and do not limit the scope of the invention.
Examples
Utilized polymerisable LC materials
The following mixtures are prepared in accordance with the following tables:
Mixture M1 :
Figure imgf000046_0001
Mixture M2:
Figure imgf000047_0001
Irganox1076 is a stabilizer, being commercially available (Ciba AG, Basel, Switzerland). NCI-930 is a photoinitiator, being commercially available (Adeka Coorporation, Japan). BYK-310 is a surfactant being commercially available (BYK, Germany).
The mixtures are each transformed to corresponding solutions by dissolving the solids in a solvent blend of toluene: cyclohexanone (7:3), at a ratio of 30% mixture M1 or M2 to 70% solvent by mass, respectively.
Application Method:
Each of the solutions are homogenized while applying a moderate elevated temperature. The solution of mixture M1 is then spin coated at 5000rpm for 30s on a commercially available glass substrate covered with polyimide. The coated film is than annealed on a hotplate at 60°C for 60s and subsequently cooled via an applied N2 purge (20l/min) with a circulator (20°C) for 60s. Curing is performed with a high pressure mercury lamp (LH6 fusion) at 10m/min with 77% power (200mJ/cm2), while applying further the N2 purge. The solution of mixture M2 is then spin coated at 4000rpm for 30s on top of polymer film 1 obtained from M1 . The layer stack is annealed on a hotplate at 60°C for 60s and subsequently cooled via an applied N2 purge (20l/min.) with a circulator (20°C) for 60s. Curing is performed with a high pressure mercury lamp (LH6 fusion) at 10m/min with 77% power (200mJ/cm2), while applying further the N2 purge. Optical Results
The resulting optical component exhibits reverse optical dispersion. The retardation profile is close to the ideal quarter wave retardation at all viewing angles and visible wavelengths. The on-axis dispersion is 0.870 while the dispersion value increases with the viewing angle and the corresponding angular dispersion profile is approximately symmetrical. The retardation profile for the wavelength of 450 nm, 550 nm and 650 nm have all the characteristics of planarly alignment polymer film of optical component. At lower wavelengths occurs typically less retardation variation with the angle of incidence.
The retardation profile (Retardation [nm]/Angle of incidence [°]), angular retardation (R450/R550 / Angle of Incidence [°]) and optical dispersion (Retardation [nm]/Wavelength [nm]) are measured via ellipsometry.
Anti-Reflection Visual Performance
An anti-reflection stack is created by arranging the optical component between a reflective surface, such as a metallic cathode of an OLED display, and a linear polariser. In comparison to a standard planar aligned film according to such as, for example described in WO 2016/020035 A1 the optical component according to the invention exhibits much dark reflection.
Conclusion
Combining the polymer films as described above results in an emulated chiral pitch. This allows for control over the final film dispersion and retardation to meet anti-reflection requirements.The spectral retardation for this the optical component according to the invention matches much closer to the ideal quarter wave plate than standard polymer films as for example described in WO 2016/020035 A1 . There is also some improvement in off-axis performance in comparison to single film applications comprising only one polymer film. The utilized mixtures consist of positive dispersion materials and no complex and expensive H-shape or T-shape LC molecules are required in order to achieve the desired effect of an reverse or negative optical dispersion of the optical component. The material cost for the optical component is much reduced compared to other reverse dispersion application methods such as, for example described in WO 2016/020035 A1 , making this a potentially viable commercial alternative for anti-reflection productions due to its simplicity and compatibility to methods of mass production.

Claims

Patent Claims Optical component comprising two or more liquid crystalline polymer films, wherein the first polymer film exhibits a uniform planar alignment of the polymerised LC molecules and the second polymer film adjacent to the first polymer film exhibits a cholesteric alignment of the polymerised LC molecules. Optical component according to claim 1 , wherein the second polymer film adjacent to the first polymer film exhibits a cholesteric alignment of the polymerised LC molecules having a % pitch rotation through the film thickness of the second polymer film. Optical component according to claim 1 or 2, exhibiting a reverse or negative optical dispersion profile. Optical component according to one or more of claims 1 to 3, wherein at least one of the polymer films is obtainable from a polymerizable LC material comprising one or more di- or multireactive mesogenic compounds Optical component according to one or more of claims 1 to 4, wherein at least one of the polymer films is obtainable from a polymerizable LC material comprising one or more di- or multireactive mesogenic compounds selected of from compounds of formula DRM,
P1-Sp1-MG-Sp2-P2 DRM wherein
P1 and P2 independently of each other denote a polymerisable group,
Sp1 and Sp2 independently of each other are a spacer group or a single bond, and
MG is a rod-shaped mesogenic group, which is selected of formula MG
-(A1-Z1)n-A2- MG wherein
A1 and A2 denote, in case of multiple occurrence independently of one another, an aromatic or alicyclic group, which optionally contains one or more heteroatoms selected from N, O and S, and which is optionally mono- or polysubstituted by L,
L is P-Sp-, F, Cl, Br, I, -CN, -NO2 , -NCO, -NCS, -OCN, -SCN, -C(=O)NRxRy, -C(=O)ORX, -
C(=O)RX, -NRxRy, -OH, -SF5, optionally substituted silyl, aryl or heteroaryl with 1 to 12, and straight chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 12, wherein one or more H atoms are optionally replaced by F or Cl,
Rx, Ry, R00 and R000 independently of each other denote H or alkyl with 1 to 12 C-atoms,
Z1 denotes, in case of multiple occurrence independently of one another, -O-, -S-, -CO-, - COO-, -OCO-, -S-CO-, -CO-S-, -O-COO-, -CO-NR00-, -NR00-CO-, -NR00-CO-NR000, -
NR00-CO-O-, -O-CO-NR00-, -OCH2-, -CH2O-, -SCH2-, -CH2S-, -CF2O-, -OCF2-, -CF2S-, -
SCF2-, -CH2CH2-, -(CH2)n1, -CF2CH2-, -CH2CF2-,
-CF2CF2-, -CH=N-, -N=CH-, -N=N-, -CH=CR00-, -CY1=CY2-, -C=C-, -CH=CH-COO-, - OCO-CH=CH- or a single bond,
Y1 and Y2 are independently of each other denote H, F, Cl or CN, n is 1 , 2, 3 or 4, n1 is an integer from 1 to 10. Optical component according to one or more of claims 1 to 5, wherein at least one of the polymer films is obtainable from a polymerizable LC material wherein the concentration of di- or multireactive mesogenic compounds, in the polymerizable LC material is in the range from 5 to 70 %. Optical component according to one or more of claims 1 to 6, wherein at least one of the polymer films is obtainable from a polymerizable LC material comprising one or more monoreactive mesogenic compounds. Optical component according to one or more of claims 1 to 7, wherein at least one of the polymer films is obtainable from a polymerizable LC material comprising one or more monoreactive mesogenic compounds selected from group of compounds of formula MRM,
P1-Sp1-MG-R MRM wherein P1, Sp1 and MG have the meanings given in formula DRM,
R denotes F, Cl, Br, I, -CN, -NO2 , -NCO, -NCS, -OCN, -SCN, -C(=O)NRxRy, -C(=O)X, - C(=O)ORX, -C(=O)Ry, -NRxRy, -OH, -SF5, optionally substituted silyl, straight chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 12, wherein one or more H atoms are optionally replaced by F or Cl,
X is halogen, and
Rx and Ry are independently of each other H or alkyl with 1 to 12 C-atoms. Optical component according to one or more of claims 1 to 8, wherein at least one of the polymer films is obtainable from a polymerizable LC material comprising one or more monoreactive mesogenic compounds in a concentration of all monoreactive RMs from 1 to 80%. 10. Optical component according to one or more of claims 1 to 9, wherein the polymer films exhibiting a cholesteric alignment of the polymerised LC molecules is obtainable from a polymerizable LC material comprising one or more chiral mesogenic compounds.
1 1 . Optical component according to one or more of claims 1 to 10, wherein the polymer films exhibiting a cholesteric alignment of the polymerised LC molecules is obtainable from a polymerizable LC material comprising one or more mono-reactive chiral compounds selected from the group of compounds of formula CRMa to CRMc,
Figure imgf000051_0002
P°* denotes a polymerisable group P
R is alkyl, alkoxy, thioalkyl, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 or more, preferably 1 to 15 C atoms or P°*-(CH2)o-X2-,
A0 and B° are, in case of multiple occurrence independently of one another, 1 ,4-phenylene that is unsubstituted or substituted with 1 , 2, 3 or 4 groups L as defined above, or trans-1 ,4-cyclohexylene,
X1 and X2 are independently of each other -O-, -COO-, -OCO-, -O-CO-O- or a single bond,
Z°* and Z° are, in case of multiple occurrence independently of one another, -COO-, -OCO-, -O-
Figure imgf000051_0001
-CH=CH-COO-, -OCO-CH=CH- or a single bond,
0 is, independently of each other 0, 1 , 2 or 3, t is 0, 1 or 2, o is 0 or an integer from 1 to 12, a and v is 0, 1 , or 2, z is 0 or 1 , and wherein the naphthalene rings can additionally be substituted with one or more identical or different groups L wherein L is, independently of each other F, Cl, CN, halogenated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 5 C atoms.
12. Method of preparing an optical component according to one or more of claims 1 to 1 1 , comprising the steps of providing a layer of a polymerizable LC medium onto a substrate, which is provided with an alignment layer capable of inducing a planar alignment to the adjacent layer of the polymerizable LC medium, irradiation of the layer stack with actinic radiation, providing a layer of a cholesteric polymerizable LC medium onto the polymer film obtained from the foregoing steps, irradiation of the layer stack with actinic radiation,
Optionally removing the layer stack or optical component from the substrate .
13. Use of an optical component according to one or more of claims 1 to 1 1 , in an optical or electrooptical device.
14. Optical or electrooptical device comprising the optical component according to one or more of claims 1 to 1 1.
15. Optical or electrooptical device according to claim 14, characterized in that it is an OLED display.
PCT/EP2023/075581 2022-09-21 2023-09-18 Polymerisable liquid crystal medium and polymerised liquid crystal film WO2024061796A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP22196759.9 2022-09-21
EP22196759 2022-09-21

Publications (1)

Publication Number Publication Date
WO2024061796A1 true WO2024061796A1 (en) 2024-03-28

Family

ID=83400741

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2023/075581 WO2024061796A1 (en) 2022-09-21 2023-09-18 Polymerisable liquid crystal medium and polymerised liquid crystal film

Country Status (1)

Country Link
WO (1) WO2024061796A1 (en)

Citations (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2004A (en) 1841-03-12 Improvement in the manner of constructing and propelling steam-vessels
US32677A (en) 1861-07-02 Washing-machine
US5389698A (en) 1991-07-26 1995-02-14 Hoffmann-La Roche Inc. Process for making photopolymers having varying molecular orientation using light to orient and polymerize
US5602661A (en) 1993-02-17 1997-02-11 Hoffmann-La Roche Inc. Optical component
WO1998000428A1 (en) 1996-07-01 1998-01-08 Merck Patent Gmbh Chiral dopants
GB2315072A (en) 1996-07-04 1998-01-21 Merck Patent Gmbh Circular UV polariser
WO1998004651A1 (en) 1996-07-26 1998-02-05 Merck Patent Gmbh Combination of optical elements
GB2328207A (en) 1997-08-13 1999-02-17 Merck Patent Gmbh Chiral hydrobenzoin derivatives for use as dopants in liquid crystalline mixtures
US6061108A (en) 1997-01-24 2000-05-09 Sharp Kabushiki Kaisha Broadband cholesteric polarizer and an optical device employing the same
WO2001020394A1 (en) 1999-09-16 2001-03-22 Merck Patent Gmbh Optical compensator and liquid crystal display i
JP2002062540A (en) 2000-08-21 2002-02-28 Fuji Xerox Co Ltd Cholesteric liquid crystal display device
US6480251B1 (en) 1998-05-28 2002-11-12 Matsushita Electric Industrial Co., Ltd. Reflection liquid crystal display element
US20030202137A1 (en) 1999-09-28 2003-10-30 Fuji Photo Film Co., Ltd. Anti-reflection film, polarizing plate comprising the same, and image display device using the anti-reflection film or the polarizing plate
US6693746B1 (en) 1999-09-29 2004-02-17 Fuji Photo Film Co., Ltd. Anti-glare and anti-reflection film, polarizing plate, and image display device
US6717644B2 (en) 1993-02-17 2004-04-06 Rolic Ag Optical component and method of manufacture
US7060200B1 (en) 1999-09-03 2006-06-13 Merck Patent Gmbh Multireactive polymerizable mesogenic compounds
EP0940707B1 (en) 1998-03-05 2006-07-12 MERCK PATENT GmbH Optical retardation film
US20060172090A1 (en) 2005-01-28 2006-08-03 Ryushi Syundo Liquid crystal polyfunctional acrylate derivative and polymer thereof
US20080158490A1 (en) 2006-06-19 2008-07-03 Fujifilm Corporaton Optical film, production method of optical film, optically-compensatory film, polarizing plate and liquid crystal display device
WO2008119427A1 (en) 2007-03-30 2008-10-09 Merck Patent Gmbh Birefringent polymer film with negative optical dispersion
WO2009058396A1 (en) 2007-11-02 2009-05-07 Akron Polymer Systems Inc. Negative birefringent optical films with flat or reversed birefringence wavelength dispersions for liquid crystal displays
US20100225856A1 (en) 2007-04-16 2010-09-09 Michael James Escuti Multi-layer achromatic liquid crystal polarization gratings and related fabrication methods
US20100225876A1 (en) 2007-04-16 2010-09-09 Michael James Escuti Low-twist chiral liquid crystal polarization gratings and related fabrication methods
US20130286479A1 (en) 2012-04-25 2013-10-31 Ko, Chi-Yuan of Cordic Technology Co. Ltd. Polarization recycling structure
US8962103B2 (en) * 2010-11-10 2015-02-24 Lg Chem, Ltd. Liquid crystal film
US20150175564A1 (en) 2012-07-09 2015-06-25 Zeon Corporation Polymerizable compound, polymerizable composition, polymer, optically anisotropic body, and method for producing polymerizable compound
US20150277007A1 (en) 2014-03-31 2015-10-01 Fujifilm Corporation Liquid crystal compound, optical film, and method for producing optical film
WO2016020035A1 (en) 2014-08-04 2016-02-11 Merck Patent Gmbh Polymerisable lc medium and polymer film with negative optical dispersion
US9298041B2 (en) 2007-04-16 2016-03-29 North Carolina State University Multi-twist retarders for broadband polarization transformation and related fabrication methods
WO2016104317A1 (en) 2014-12-25 2016-06-30 Dic株式会社 Polymerizable compound and optically anisotropic object
WO2016171041A1 (en) 2015-04-24 2016-10-27 日本ゼオン株式会社 Multilayer film manufacturing method and multilayer film
WO2017079867A1 (en) 2015-11-09 2017-05-18 Dic Corporation Polymerizable compound and optically anisotropic body

Patent Citations (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US32677A (en) 1861-07-02 Washing-machine
US2004A (en) 1841-03-12 Improvement in the manner of constructing and propelling steam-vessels
US5389698A (en) 1991-07-26 1995-02-14 Hoffmann-La Roche Inc. Process for making photopolymers having varying molecular orientation using light to orient and polymerize
US6717644B2 (en) 1993-02-17 2004-04-06 Rolic Ag Optical component and method of manufacture
US5602661A (en) 1993-02-17 1997-02-11 Hoffmann-La Roche Inc. Optical component
WO1998000428A1 (en) 1996-07-01 1998-01-08 Merck Patent Gmbh Chiral dopants
GB2315072A (en) 1996-07-04 1998-01-21 Merck Patent Gmbh Circular UV polariser
WO1998004651A1 (en) 1996-07-26 1998-02-05 Merck Patent Gmbh Combination of optical elements
US6061108A (en) 1997-01-24 2000-05-09 Sharp Kabushiki Kaisha Broadband cholesteric polarizer and an optical device employing the same
GB2328207A (en) 1997-08-13 1999-02-17 Merck Patent Gmbh Chiral hydrobenzoin derivatives for use as dopants in liquid crystalline mixtures
EP0940707B1 (en) 1998-03-05 2006-07-12 MERCK PATENT GmbH Optical retardation film
US6480251B1 (en) 1998-05-28 2002-11-12 Matsushita Electric Industrial Co., Ltd. Reflection liquid crystal display element
US7060200B1 (en) 1999-09-03 2006-06-13 Merck Patent Gmbh Multireactive polymerizable mesogenic compounds
US20050134774A1 (en) * 1999-09-16 2005-06-23 David Coates Optical compensator and liquid crystal display I
WO2001020394A1 (en) 1999-09-16 2001-03-22 Merck Patent Gmbh Optical compensator and liquid crystal display i
US20030202137A1 (en) 1999-09-28 2003-10-30 Fuji Photo Film Co., Ltd. Anti-reflection film, polarizing plate comprising the same, and image display device using the anti-reflection film or the polarizing plate
US6693746B1 (en) 1999-09-29 2004-02-17 Fuji Photo Film Co., Ltd. Anti-glare and anti-reflection film, polarizing plate, and image display device
JP2002062540A (en) 2000-08-21 2002-02-28 Fuji Xerox Co Ltd Cholesteric liquid crystal display device
US20060172090A1 (en) 2005-01-28 2006-08-03 Ryushi Syundo Liquid crystal polyfunctional acrylate derivative and polymer thereof
US20080158490A1 (en) 2006-06-19 2008-07-03 Fujifilm Corporaton Optical film, production method of optical film, optically-compensatory film, polarizing plate and liquid crystal display device
US20100110362A1 (en) 2007-03-30 2010-05-06 Owain Llyr Parri Birefringent Polymer Film with Negative Optical Dispersion
WO2008119427A1 (en) 2007-03-30 2008-10-09 Merck Patent Gmbh Birefringent polymer film with negative optical dispersion
US20100225856A1 (en) 2007-04-16 2010-09-09 Michael James Escuti Multi-layer achromatic liquid crystal polarization gratings and related fabrication methods
US20100225876A1 (en) 2007-04-16 2010-09-09 Michael James Escuti Low-twist chiral liquid crystal polarization gratings and related fabrication methods
US9298041B2 (en) 2007-04-16 2016-03-29 North Carolina State University Multi-twist retarders for broadband polarization transformation and related fabrication methods
WO2009058396A1 (en) 2007-11-02 2009-05-07 Akron Polymer Systems Inc. Negative birefringent optical films with flat or reversed birefringence wavelength dispersions for liquid crystal displays
US8962103B2 (en) * 2010-11-10 2015-02-24 Lg Chem, Ltd. Liquid crystal film
US20130286479A1 (en) 2012-04-25 2013-10-31 Ko, Chi-Yuan of Cordic Technology Co. Ltd. Polarization recycling structure
US20150175564A1 (en) 2012-07-09 2015-06-25 Zeon Corporation Polymerizable compound, polymerizable composition, polymer, optically anisotropic body, and method for producing polymerizable compound
US20150277007A1 (en) 2014-03-31 2015-10-01 Fujifilm Corporation Liquid crystal compound, optical film, and method for producing optical film
WO2016020035A1 (en) 2014-08-04 2016-02-11 Merck Patent Gmbh Polymerisable lc medium and polymer film with negative optical dispersion
WO2016104317A1 (en) 2014-12-25 2016-06-30 Dic株式会社 Polymerizable compound and optically anisotropic object
WO2016171041A1 (en) 2015-04-24 2016-10-27 日本ゼオン株式会社 Multilayer film manufacturing method and multilayer film
WO2017079867A1 (en) 2015-11-09 2017-05-18 Dic Corporation Polymerizable compound and optically anisotropic body

Non-Patent Citations (10)

* Cited by examiner, † Cited by third party
Title
"Merck Liquid Crystals, Physical Properties of Liquid Crystals", November 1997, MERCK KGAA
"Retardation Measurement (RetMeas) Manual", 2002, J. A. WOOLLAM CO. INC, article "Woollam Variable Angle Spectroscopic Ellipsometer"
A. UCHIYAMAT. YATABE: "Control of Wavelength Dispersion of Birefringence for Oriented Copolycarbonate Films Containing Positive and Negative Birefringent Units", J. APPL. PHYS., vol. 42, 2003, pages 6941 - 6945, XP055347221, DOI: 10.1143/JJAP.42.6941
C. TSCHIERSKEG. PELZLS. DIELE, ANGEW. CHEM., vol. 116, 2004, pages 6340 - 6368
I. SAGE: "Thermotropic Liquid Crystals", 1987, JOHN WILEY & SONS, pages: 75 - 77
J. COGNARD: "Mol. Cryst. Liq. Cryst", vol. 78, 1981, pages: 1 - 77
JAP. J. APPL. PHYS., vol. 42, 2003, pages 3463
N. SINGH: "National Physics Laboratory", October 2006, article "Spectroscopic Ellipsometry, Part 1-Theory and Fundamentals, Part 2 - Practical Examples and Part 3 - measurements"
RAVI K. KOMANDURIKRISTOPHER F. LAWLERMICHAEL J. ESCUTI, OPTICS EXPRESS, vol. 21, no. 1, 14 January 2013 (2013-01-14), pages 404
T. UCHIDAH. SEKI: "Liquid Crystals - Applications and Uses", vol. 3, 1992, SCIENTIFIC PUBLISHING, pages: 1 - 63

Similar Documents

Publication Publication Date Title
EP3246378B1 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
US11820932B2 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
KR102587323B1 (en) Polymerizable liquid crystal materials and polymerized liquid crystal films
WO2019207081A1 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
EP4217442A1 (en) Polymerizable liquid crystal material and polymerized liquid crystal film
EP3784753A1 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
WO2017148567A1 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
WO2020187810A1 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
WO2020035400A1 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
US11939510B2 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
WO2020035401A1 (en) Polymerizable liquid crystal material and polymerized liquid crystal film
EP3548585B1 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
US11697769B2 (en) Polymerizable liquid crystal material and polymerized liquid crystal film
EP3891251B1 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
US20200255736A1 (en) Polymerisable liquid crystal material and polymerised liquid crystal film
WO2024061796A1 (en) Polymerisable liquid crystal medium and polymerised liquid crystal film
WO2023237572A1 (en) Polymerisable liquid crystal medium and polymerised liquid crystal film
WO2024052363A1 (en) Polymerizable liquid crystal material and polymerized liquid crystal film
WO2024042008A1 (en) Polymerizable liquid crystal material and polymerized liquid crystal film
WO2022003079A1 (en) Polymerisable liquid crystal material and polymerised liquid crystal film

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: 23772261

Country of ref document: EP

Kind code of ref document: A1