JP2007332229A - Liquid crystal composition, and color filter and liquid crystal display device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal composition from which a phase difference layer excellent in the point of hardness can easily and inexpensively be produced; to provide a color filter having the phase difference layer formed by using the composition, and a liquid crystal display using the color filter. <P>SOLUTION: The liquid crystal composition from which the phase difference layer excellent in the point of hardness can be produced contains a crosslinkable liquid crystal molecule, and a polyfunctional molecule having an alcoholic hydroxy group and a polymerizable functional group in the molecular structure. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal composition, a color filter having a retardation layer made of the liquid crystal composition, and a liquid crystal display device using the color filter.

  Since the liquid crystal display device has the great advantages of being thin and light and low power consumption, it is actively used in display devices such as personal computers, mobile phones, and electronic notebooks. These liquid crystal display devices perform light switching by utilizing the birefringence of liquid crystal (driving liquid crystal) molecules contained in the driving liquid crystal layer. Therefore, the liquid crystal display device has a problem of viewing angle dependency derived from the birefringence of the driving liquid crystal, and in order to solve this problem using a retardation layer that compensates for the phase difference of light, various retardations are used. For example, a retardation layer forming film has been developed as a member having a layer formed thereon. This retardation layer forming film is usually produced by stretching a film of polyacrylate, polycarbonate, triacetyl cellulose or the like. The retardation forming film is usually installed at an outer position of a liquid crystal cell having a structure in which a liquid crystal is sealed between a facing display side substrate and a driving liquid crystal side substrate. In such a liquid crystal cell, the retardation layer is disposed at the outer position.

  In addition, the retardation layer is not limited to the case where the retardation layer is installed outside the liquid crystal cell as described above, and recently, a method of installing the retardation layer inside the liquid crystal cell using a crosslinkable liquid crystal or a polymer liquid crystal has been proposed. (Patent Document 1), a high mechanical strength and heat resistance can be obtained by providing a retardation layer inside the liquid crystal cell.

  As for the retardation layer installed inside the liquid crystal cell, a method of laminating a protective layer on the surface of the retardation layer has been proposed in order to further improve the mechanical strength (Patent Document 2). Furthermore, a method for forming a retardation layer having a high hardness by aligning and curing a polymerizable monomer having a special skeleton on an alignment film has also been proposed (Patent Document 3).

JP 2000-221506 A JP 2004-126534 A JP 2005-309255 A

  However, since the method proposed in Patent Document 2 is a method of laminating a protective film on the retardation layer, there is a problem in that the number of manufacturing steps increases, yield decreases, and manufacturing costs increase. In addition, the method proposed in Patent Document 3 is a method that requires the use of a polymerizable monomer having a special molecular skeleton structure as a material. Therefore, the synthesis of the material is complicated, and the production cost is also low. The rise was a problem.

  The present invention has been made in view of the above problems, and a liquid crystal composition capable of forming a retardation layer easily and inexpensively and forming a retardation layer excellent in hardness, and using the same It is an object of the present invention to provide a color filter having a formed retardation layer and a liquid crystal display device using the color filter.

The present invention comprises (1) a crosslinkable liquid crystal molecule and a polyfunctional molecule having an alcoholic hydroxyl group and a polymerizable functional group in the molecular structure,
(2) The liquid crystal composition according to the above (1), wherein the crosslinkable liquid crystal molecule has at least one (meth) acryloyl group in at least one molecule.
(3) The liquid crystal composition according to (1) or (2), wherein the polyfunctional molecule is contained in an amount of 5 to 20% by weight in terms of the formulation.
(4) The liquid crystal composition according to any one of (1) to (3), wherein the polyfunctional molecule is a polyfunctional (meth) acrylate,
(5) Polyfunctional (meth) acrylate is 2-hydroxy 1-3 dimethacryloxy propane, 2-hydroxy 1-3 dimethacryloxy propane, 2-hydroxy, 1-acryloxy, 3-methacryloxy propane, ethylene bis [ Oxy (2-hydroxypropane-1,3-diyl)] dimethacrylate, (1-methyl-1,2-ethanediyl) bis [oxy (2-hydroxy-3,1-propanediyl)] diacrylate, bisphenol A- The liquid crystal composition according to the above (4), selected from glycidyl methacrylate, bisphenol A-glycidyl acrylate, and pentaerythritol diacrylate monostearate;
(6) The liquid crystal composition according to the above (4), wherein the polyfunctional (meth) acrylate is pentaerythritol triacrylate,
(7) The liquid crystal composition according to (4), wherein the polyfunctional (meth) acrylate is dipentaerythritol hydroxypentaacrylate,
(8) A colored layer and a retardation layer are laminated on a light-transmitting substrate, and the retardation layer cures the liquid crystal composition according to any one of the above (1) to (7). A color filter characterized by being formed,
(9) The retardation layer is directed toward the surface of the liquid crystal coating film with respect to the liquid crystal coating film formed by coating the liquid crystal composition according to any one of (1) to (7) on the colored layer. The color filter according to (8) above, which is formed by irradiating light to cure the crosslinkable liquid crystal molecules.
(10) The retardation layer contains (meth) acryloyl group containing at least 94.9 to 70% by weight of the crosslinkable liquid crystal molecules in terms of the compound and 0.1 to 10% in terms of the compound. % Of a photopolymerization initiator and a liquid crystal composition containing 5 to 20% by weight of a polyfunctional molecule in terms of the formulation, photocured and baked, and the pencil hardness of the retardation layer is JIS K5600-5 The color filter according to (8) or (9) above, wherein the color filter is 2H or more by evaluation according to -4,
(11) The color filter according to any one of (8) to (10), wherein the crosslinkable liquid crystal molecules contained in the phase difference phase are homeotropically aligned.
(12) A liquid crystal display device in which a liquid crystal material is sealed between an opposing display side substrate and a driving liquid crystal side substrate to form a driving liquid crystal layer, wherein the display side substrate is the above (8) to (11). The gist of the liquid crystal display device is a color filter according to any one of the above.

  In addition, in this specification, the conversion value relative to the compound for what is blended as a component constituting the liquid crystal composition (referred to as a compound component (excluding a solvent when the liquid crystal composition includes a solvent)) is , When the total weight of the liquid crystal composition (however, when the liquid crystal composition contains a solvent, excluding the weight of the solvent) is 100, the weight ratio (% by weight) of the target formulation component Indicates the value.

  The liquid crystal composition of the present invention contains a crosslinkable liquid crystal molecule and a polyfunctional molecule having an alcoholic hydroxyl group and a polymerizable functional group. Accordingly, the liquid crystal composition of the present invention is applied onto the substrate surface to form a film (liquid crystal coating film), and a predetermined orientation is imparted to the crosslinkable liquid crystal molecules contained in the liquid crystal coating film. When the cross-linkable liquid crystal molecules are polymerized and cured to form a retardation layer, the hardness of the retardation layer can be increased by polyfunctional molecules while maintaining the excellent viewing angle improvement function of the retardation layer. . In addition, the retardation layer obtained from the liquid crystal composition can be easily and inexpensively manufactured and has excellent mechanical strength over a long period of time. For this reason, a color filter in which a retardation layer is formed from the liquid crystal composition of the present invention and a liquid crystal display device using this color filter as a display-side substrate exhibit an excellent viewing angle improvement effect over a long period of time.

  Further, according to the present invention, the use of a polyfunctional molecule having a hydroxyl group and a polymerizable functional group improves the compatibility with the crosslinkable liquid crystal (admixes well).

  The liquid crystal composition of the present invention is a composition containing a crosslinkable liquid crystal molecule having a crosslinkable molecular structure and a polyfunctional molecule.

  Examples of the crosslinkable liquid crystal molecules used in the liquid crystal composition of the present invention include nematic liquid crystal molecules having crosslinkability (crosslinkable nematic liquid crystal molecules). Examples of the crosslinkable nematic liquid crystal molecules include monomers, oligomers, and polymers having at least one polymerizable group such as a (meth) acryloyl group, an epoxy group, an octacene group, and an isocyanate group in one molecule. As such a crosslinkable liquid crystal molecule, more specifically, one compound (compound (I)) or two or more compounds represented by the following general formula (1) A mixture, a compound of the compounds shown in Chemical Formula 2 and Chemical Formula 3 (Compound (II)), a mixture of two or more, or a combination thereof can be used.

In the general formula (1) shown in Chemical Formula 1, R ¹ and R ² each represent hydrogen or a methyl group, but in order to broaden the temperature range in which the crosslinkable liquid crystal molecules exhibit a liquid crystal phase, R ¹ and Both R ² are preferably hydrogen. X may be any of hydrogen, chlorine, bromine, iodine, an alkyl group having 1 to 4 carbon atoms, a methoxy group, a cyano group, or a nitro group, but is preferably a chlorine or methyl group. In addition, a and b indicating the chain length of the alkylene group between the (meth) acryloyloxy group and the aromatic ring at both ends of the molecular chain of the general formula (1) each independently take an arbitrary integer in the range of 2 to 12. However, it is preferably in the range of 4-10, more preferably in the range of 6-9. The compound (I) of the general formula (1) in which a = b = 0 is poor in stability, is susceptible to hydrolysis, and the crystallinity of the compound (I) itself is high. Further, the compound (I) of the general formula (1) in which a and b are each 13 or more has a low isotropic phase transition temperature (TI). For these reasons, both of these compounds have a narrow temperature range (temperature range in which the liquid crystal phase is maintained) that stably exhibits liquid crystallinity, and are not preferable for use in the liquid crystal composition of the present invention.

  As the crosslinkable liquid crystal molecules to be blended in the liquid crystal composition, the above-described chemical formula 1, chemical formula 2, and chemical formula 3 exemplify liquid crystal (polymerizable liquid crystal) monomers having polymerizable properties. These polymers may be used, and for these, well-known ones such as the above-mentioned oligomers and polymers such as Chemical Formula 1, Chemical Formula 2, and Chemical Formula 3 can be appropriately selected and used.

  The retardation amount and the alignment characteristics indicating the characteristics of the retardation layer are determined by the birefringence Δn of the crosslinkable liquid crystal molecules and the film thickness of the retardation layer, but the retardation layer in which the crosslinkable liquid crystal molecules are homeotropically aligned is used. In the case of forming an optical element having a so-called positive C plate, Δn of the crosslinkable liquid crystal molecules is preferably about 0.03 to 0.20, and more preferably about 0.05 to 0.15. Homeotropic alignment means that the crosslinkable liquid crystal molecules are in the retardation layer so that the direction of the optical axis of the crosslinkable liquid crystal molecules is substantially perpendicular to the phase difference layer surface (ideally, the perpendicular direction). Shows the state of being arranged.

  The polyfunctional molecule used in the liquid crystal composition of the present invention is a molecule containing two or more polymerizable functional groups in the molecular structure. As the polyfunctional molecule, those containing an alcoholic hydroxyl group in the molecular structure are preferably used. be able to. The number of alcoholic hydroxyl groups contained in this polyfunctional molecule is usually 1 to 3, but 1 or 2 is preferable because it effectively prevents the orientation of the crosslinkable liquid crystal molecules from being disturbed.

  Moreover, as a polymerizable functional group in a polyfunctional molecule, a (meth) acrylate group, an epoxy group, or an oxetane group can be mentioned. For the reason of high reactivity, a polyfunctional molecule is a polymerizable functional group ( A polyfunctional (meth) acrylate having a (meth) acrylate is preferable. Furthermore, as the polyfunctional (meth) acrylate, polyfunctional (meth) acrylate having an alcoholic hydroxyl group in the molecular structure, that is, polyfunctional acrylate and / or polyfunctional methacrylate can be preferably used.

  Examples of the polyfunctional (meth) acrylate containing an alcoholic hydroxyl group include monomers, oligomers, and polymers having at least one alcoholic hydroxyl group in one molecule. As such a polyfunctional (meth) acrylate, specifically, one compound or a mixture of two or more of the compounds represented by the general formula shown below (compound (III)) is used. Can do.

In the general formula shown in Chemical Formula 4, m represents an integer of 1 to 3, n represents an integer of 2 or more, R ¹ represents an organic hydrocarbon structure having 1 or more carbon atoms, and R ² represents hydrogen or methyl, respectively. Indicates a group. In the general formula shown in Chemical formula 4, any molecular weight compound can be used, and 2-hydroxy 1-3 dimethacryloxypropane, 2-hydroxy, 1-acryloxy, 3-methacryloxypropane, ethylenebis [oxy (2 -Hydroxypropane-1,3-diyl)] dimethacrylate, (1-methyl-1,2-ethanediyl) bis [oxy (2-hydroxy-3,1-propanediyl)] diacrylate, bisphenol A-glycidyl methacrylate, Bisphenol A-glycidyl acrylate, pentaerythritol diacrylate monostearate, pentaerythritol triacrylate, dipentaerythritol hydroxypentaacrylate, and the like can be mentioned. From the viewpoint of compatibility with crosslinkable liquid crystal molecules, the molecular weight is 1000 or less. There are preferred.

  The polyfunctional molecule containing an alcoholic hydroxyl group needs to be added within a range that does not significantly impair the orientation of the crosslinkable liquid crystal molecules contained in the liquid crystal composition, and is generally 5. It is added so as to be 0 to 20% by weight, preferably 10 to 15% by weight. When the blending amount of the polyfunctional molecule is 5.0% by weight or less, the hardness in the thickness direction of the retardation layer obtained when the retardation layer is formed using the liquid crystal composition is not sufficiently improved, and the polyfunctional molecule is not functional. When the blending amount of the molecules is 20% by weight or more, there is a possibility that the orientation of the crosslinkable liquid crystal molecules is likely to be disturbed when trying to give a certain alignment to the crosslinkable liquid crystal molecules contained in the liquid crystal composition.

  In the liquid crystal composition, a polymerization initiator such as a photopolymerization initiator is usually blended. As the photopolymerization initiator, a radical polymerizable initiator can be used. Radical polymerizable initiators are compounds that generate free radicals by the energy of ultraviolet rays, for example, benzophenone derivatives such as benzoin and benzophenone or derivatives thereof; xanthone and thioxanthone derivatives; chlorosulfonyl, chloromethyl polynuclear aromatic compounds Halogen-containing compounds such as chloromethyl heterocyclic compounds and chloromethylbenzophenones; triazines; fluorenones; haloalkanes; redox couples of photoreductive dyes and reducing agents; organic sulfur compounds; It is done. As photopolymerization initiators, Irgacure 184, Irgacure 369, Irgacure 651, Irgacure 907 (all manufactured by Ciba Specialty Chemicals), Darocur (Merck), Adeka 1717 (Asahi Denka Kogyo) Co., Ltd.), 2,2′-bis (o-chlorophenyl) -4,5,4′-tetraphenyl-1,2′-biimidazole (manufactured by Kurokin Kasei Co., Ltd.), etc. Compounds and the like are preferred. These polymerization initiators can be used alone or in combination of two or more. When using 2 or more types together, it is preferable to combine polymerization initiators having different absorption wavelengths so as not to inhibit the absorption spectral characteristics.

  The photopolymerization initiator needs to be added within a range that does not impair the alignment performance of the crosslinkable liquid crystal molecules in the liquid crystal composition, and is generally 0.01 to 15% by weight in terms of the formulation, Preferably, it is added in an amount of 0.1 to 12% by weight, more preferably 0.5 to 10% by weight.

  In addition, although a polymerization inhibitor may be added to the liquid crystal composition, the storage stability of the liquid crystal composition can be further improved. In addition to the photopolymerization initiator, a sensitizer, a surfactant and the like can be appropriately added to the liquid crystal composition as long as the object of the present invention is not impaired.

  In the case of producing an optical element having a retardation layer in which crosslinkable liquid crystal molecules are homeotropically aligned, that is, a so-called positive C plate, using the liquid crystal composition of the present invention, a vertical alignment aid is added to the liquid crystal composition. May be blended. The vertical alignment aid has an effect of making the alignment state of the crosslinkable liquid crystal molecules more stable and reliable when the crosslinkable liquid crystal molecules are homeotropically aligned. Vertical alignment aids include surface coupling agents having vertically aligned alkyl or fluorocarbon chains such as lecithin or quaternary ammonium surfactants such as HTAB (hexadecyl-trimethylammonium bromide), DMOAP (N, N- Specific examples thereof include dimethyl-N-octadecyl-3-aminopropyltrimethoxysilyl chloride) or N-perfluorooctylsulfonyl-3-aminopropyltrimethylammonium iodide, silane polymer, and long-chain alkyl alcohol.

  The vertical alignment aid is blended so as to be 0.1 to 10% by weight, preferably 0.5 to 5% by weight, in terms of the compound. A particularly preferable amount of the vertical alignment aid is 0.8 to 2% by weight in terms of the compound equivalent. When the content of the vertical alignment aid relative to the total amount of the composition components is less than 0.1% by weight, it may not sufficiently contribute to imparting homeotropic alignment to the crosslinkable liquid crystal molecules contained in the liquid crystal composition. When the weight percentage is exceeded, the alignment performance of the crosslinkable liquid crystal molecules in the liquid crystal composition is hindered, and when the liquid crystal composition is cured by crosslinking polymerization of the crosslinkable liquid crystal molecules, the curing rate decreases and the crosslinking density decreases. There is a risk of causing problems such as a decrease.

  In the case of producing a positive C plate using the liquid crystal composition of the present invention, it is necessary to add compound components other than the crosslinkable liquid crystal molecules so as to be 30% by weight or less in terms of the compound equivalent. . If compound components other than the crosslinkable liquid crystal molecules are added in an amount of 30% by weight or more in terms of the compound, the orientation of the crosslinkable liquid crystal molecules may be deteriorated. However, in the case where a so-called negative C plate is prepared using a liquid crystal composition constituted by adding a chiral agent, the compound components other than the crosslinkable liquid crystal molecules are converted into the compound equivalent value. It is not excluded that the addition amount of the crosslinkable liquid crystal molecules is less than 70% by weight.

  In addition, when the liquid crystal composition of the present invention is used to form an optical element, a so-called negative C plate, in which a cholesteric regularity is imparted to crosslinkable liquid crystal molecules to form a chiral nematic liquid crystal and a retardation layer is formed. In addition, a chiral agent may be added to the liquid crystal composition.

  The chiral agent is preferably a low molecular weight compound having an optically active site in the molecule and having a molecular weight of 1500 or less. Specifically, examples of the chiral agent include compounds as shown in the following chemical formula 5, but the compound (I) shown in chemical formula 1 or the compound (II) shown in chemical formula 2 or chemical formula 3 and a solution state or As long as it has compatibility in the molten state and can induce the helical pitch without impairing the liquid crystal properties of the crosslinkable nematic liquid crystal molecules, the compound is not limited to the compound shown in Chemical Formula 5. However, as the chiral agent, those having a crosslinkable functional group at both ends in the molecular structure are preferable for obtaining a retardation layer having good heat resistance, and the chiral agent has an optically active site in the molecular structure. It is important to be a compound.

  When such a chiral agent is blended in a liquid crystal composition containing the compound (I) shown in Chemical Formula 1 or the compound (II) shown in Chemical Formula 2 or Chemical Formula 3 as a crosslinkable liquid crystal molecule, the liquid crystal composition is used. In forming the retardation layer, a helical pitch can be induced with positive uniaxial nematic regularity with respect to the crosslinkable liquid crystal molecules contained in the retardation layer.

  Examples of the chiral agent that can be used in the present invention include a compound having one or more asymmetric carbons, a compound having an asymmetric point on a heteroatom such as a chiral amine, a chiral sulfoxide, or the like. And compounds having axial asymmetry such as binaphthol. Depending on the properties of the selected chiral agent, nematic regularity may be destroyed and the orientation may be lowered, and in the case of a non-polymerizable chiral agent, the curing performance due to the polymerization of the crosslinkable liquid crystal may be reduced. There is a risk of reducing the electrical reliability of the retardation layer formed using the liquid crystal composition, and the use of a large amount of a chiral agent having an optically active site causes an increase in cost. Therefore, as the chiral agent used in the present invention, it is preferable to select a chiral agent having a large effect of inducing a helical pitch in the alignment of liquid crystal even in a small amount, specifically, the general formulas (2) to (4) described in Chemical formula 5 It is preferable to use a low molecular weight compound having an axial asymmetry in the molecule. More specifically, as the chiral agent, for example, a commercially available product such as S-811 manufactured by Merck can be used.

In the general formulas (2) to (4), R ⁴ represents hydrogen or a methyl group, and Y is any one of (i) to (xxiv) shown in the following chemical formula 6 and chemical formula 7; (I), (ii), (iii), (v) and (vii) are preferred. In addition, it is more preferable that c and d, which indicate the number of repeating alkylene groups, each individually range from 2 to 12. A compound in which the value of c or d is 0 or 1 lacks stability, is susceptible to hydrolysis, and has high crystallinity. On the other hand, a compound having a value of c or d of 13 or more has a low melting point (Tm). As a result, when a compound in which the values of c and d are outside the above preferred range is used as the chiral agent, the compatibility with the crosslinkable liquid crystal molecules exemplified by the compound (I) or the compound (II) is lowered, and depending on the concentration There is a risk of phase separation and the like.

  The optimum range of the amount of the chiral agent is appropriately determined in consideration of the ability to induce helical pitch and the degree of cholesteric regularity of the crosslinkable liquid crystal molecules contained in the finally obtained retardation layer. It varies greatly depending on the type of liquid crystal molecules. Specifically, the chiral agent is generally 0.01 to 30% by weight, preferably 0.1 to 20% by weight, and more preferably 0.5 to 15% by weight in terms of the compound. Is blended into. A particularly preferable amount of the chiral agent is 1 to 15% by weight in terms of the compound. When the content of the chiral agent in the composition component is less than 0.01% by weight, the cholesteric regularity may not be sufficiently imparted to the crosslinkable liquid crystal molecules contained in the liquid crystal composition. In the case of exceeding, the alignment performance of the crosslinkable liquid crystal molecules in the liquid crystal composition is hindered, and when the liquid crystal composition is cured by crosslinking polymerization of the crosslinkable liquid crystal molecules, the curing rate is lowered or the crosslinking density is lowered. May cause problems.

  The chiral agent used in the present invention is not particularly required to have crosslinkability, but considering the thermal stability of the obtained retardation layer, the crosslinkable liquid crystal molecules contained in the liquid crystal composition It is preferable to use a chiral agent having a crosslinking ability that can be polymerized and fix a state in which cholesteric regularity is imparted to the crosslinkable liquid crystal molecules. As such a chiral agent, in particular, those having a crosslinkable functional group at both ends of the molecular structure of the chiral agent are more preferable for improving the heat resistance of the retardation layer.

  The liquid crystal composition of the present invention may be formed by mixing components such as the crosslinkable liquid crystal molecules constituting the liquid crystal composition, or may be formed in a state of being suspended or dissolved in a solvent as appropriate. . When the liquid crystal composition is in the state of a solution dissolved in a solvent, the coating property can be improved. In this case, the solvent is not particularly limited as long as it can dissolve compound components such as the above-described crosslinkable liquid crystal and silane coupling agent and does not impair the performance of the counterpart material to be applied. is not.

  Specific examples of the solvent for dissolving the compound components include hydrocarbons such as benzene, toluene, xylene, n-butylbenzene, diethylbenzene, and tetralin, and ethers such as methoxybenzene, 1,2-dimethoxybenzene, and diethylene glycol dimethyl ether. , Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 2,4-pentanedione, ethyl acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, γ-butyrolactone, etc. Amides such as esters, 2-pyrrolidone, N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, chloroform, dichloro Halogen solvents such as methane, carbon tetrachloride, dichloroethane, tetrachloroethane, tritrichloroethylene, tetrachloroethylene, chlorobenzene, orthodichlorobenzene, t-butyl alcohol, diacetone alcohol, glycerin, monoacetin, ethylene glycol, triethylene glycol, hexylene glycol, One or more alcohols such as ethylene glycol monomethyl ether, ethyl cellosolve and butyl cellosolve, and phenols such as phenol and parachlorophenol can be used. If only one type of solvent is used, the solubility of compound components such as crosslinkable liquid crystal molecules is insufficient, or if there is a risk that the material of the other side to be coated may be affected, two or more types These disadvantages can be avoided by mixing the solvents. Among the above-mentioned solvents, hydrocarbon solvents and glycol monoether acetate solvents are preferable as the sole solvent, and preferable solvents are ethers or ketones and glycols mixed. It is a mixed solvent. The concentration of the compound component of the liquid crystal composition solution varies depending on the solubility of the compound component used in the liquid crystal composition in the solvent and the layer thickness desired for the retardation layer, but is usually 1 to 60% by weight, preferably It is in the range of 3 to 40% by weight.

  According to the liquid crystal composition of the present invention, it can be applied to a substrate to form a retardation layer to form an optical element. This optical element can be used as an element that can be incorporated in a liquid crystal display device and can exhibit a phase difference compensation function for adjusting a viewing angle.

  Further, according to the liquid crystal composition of the present invention, a retardation layer can be directly formed on a member constituting the liquid crystal display device. For example, the retardation layer is provided on a color filter constituting the liquid crystal display device. it can. Even in this case, the retardation layer can exhibit a retardation compensation function for adjusting the viewing angle in the liquid crystal display device.

  Next, a color filter provided with a retardation layer will be described with reference to the drawings.

FIG. 1 shows an embodiment of a color filter according to the present invention.
The color filter 1 includes a black matrix 5 (BM), a red (R) sub-pixel 6, a green (G) sub-pixel 7, and a blue (B) sub-pixel 8 on the surface of the substrate 2. 3 is formed, and a retardation layer 4 is further laminated on the surface of the colored layer 3.

  The substrate 2 is preferably transparent and optically isotropic with light transmission, but if necessary, a region having optical anisotropy or a region having light shielding properties is locally applied. It can also be provided. The light transmittance can be appropriately selected according to the use of the color filter.

  Specifically, the substrate 2 may be a base material (organic base material) based on an organic material in addition to a base material based on an inorganic material such as glass, silicon, or quartz. Examples of organic substrates include acrylics such as polymethyl methacrylate, polyamide, polyacetal, polybutylene terephthalate, polyethylene terephthalate, polyethylene naphthalate, triacetyl cellulose, or syndiotactic polystyrene, polyphenylene sulfide, polyether ketone, polyether Ether ketone, fluororesin, polyether nitrile, etc., polycarbonate, modified polyphenylene ether, polycyclohexene, polynorbornene resin, etc., or polysulfone, polyethersulfone, polysulfone, polypropylene, polyarylate, polyamideimide, polyetherimide , Polyetherketone, or thermoplastic polyimide. That it can also be used which generally consists of plastic. Also about the thickness of the board | substrate 2, the thing of about 5 micrometers-3 mm is used according to a use, for example.

  On the substrate 2, a black matrix 5 (BM) is provided in a predetermined position and pattern, and further, a red (R) sub-pixel 6, a green (G) sub-pixel 7, and a blue (B) sub-pixel. Sub-pixels 8 are sequentially provided, and the colored layer 3 is formed by a black matrix 5 (BM), a red (R) sub-pixel 6, a green (G) sub-pixel 7, and a blue (B) sub-pixel 8. It is formed.

  The black matrix 5 is an area corresponding to the position where the sub-pixels (colored sub-pixels) 6, 7, 8 of each color are arranged on the surface of the substrate 2, for each colored sub-pixel 6, 7, 8 in plan view. It is formed so as to be partitioned.

  The black matrix 5 can be formed by patterning a light-shielding or light-absorbing metal thin film such as a metal chromium thin film or a tungsten thin film on the surface of the substrate 2 in a predetermined shape. The black matrix 5 can also be formed by printing an organic material such as a black resin in a predetermined shape.

  The red (R) sub-pixel 6, the green (G) sub-pixel 7, and the blue (B) sub-pixel 8 constituting the colored layer 3 are each dispersed in a solvent with coloring materials for red, green, and blue, respectively. In addition to being formed by patterning the coating film of the colored material dispersion liquid into a predetermined shape by, for example, photolithography, a solution (coloring material dispersion liquid) in which the coloring material corresponding to each color of the colored sub-pixel is dispersed is formed. Patterning can also be performed by applying in a predetermined shape. As a patterning pattern for applying the coloring material dispersion, various patterns such as a stripe type, a mosaic type, and a triangle type can be appropriately selected.

  The retardation layer 4 is formed by forming a film as follows using the liquid crystal composition of the present invention.

  On the surface of the colored layer 3, the liquid crystal composition of the present invention is applied to form a liquid crystal coating film. For the application of the liquid crystal composition, for example, gravure printing, offset printing, relief printing, screen printing, transfer printing, electrostatic printing, plateless printing, gravure coating, roll coating, etc. Coating methods such as coating method, knife coating method, air knife coating method, bar coating method, dip coating method, kiss coating method, spray coating method, die coating method, comma coating method, ink jet method, spin coating method, slit coating method, etc. A combination of these methods can be used as appropriate.

  In the formation of the liquid crystal coating film, when the surface of the colored layer 3 is preliminarily subjected to UV (ultraviolet) treatment (UV cleaning treatment) or corona discharge treatment (corona treatment), The wettability of the colored layer 3 is improved, and the contact between the colored layer 3 and the liquid crystal coating film can be made closer, which is preferable.

  When the liquid crystal coating film is formed on the colored layer 3, the crosslinkable liquid crystal molecules included in the liquid crystal coating film are given a predetermined orientation to crosslink polymerize the crosslinkable liquid crystal molecules.

  For example, when the liquid crystal coating film is used as the retardation layer 4 having a function as a positive C plate, the crosslinkable liquid crystal molecules are polymerized by homeotropic alignment of the crosslinkable liquid crystal molecules in the liquid crystal coating film. Giving homeotropic alignment to the crosslinkable liquid crystal molecules means that the liquid crystal coating film is heated by means of heating with infrared rays, etc., and the temperature of the liquid crystal coating film is changed so that the crosslinkable liquid crystal contained therein has a liquid crystal phase. The temperature (liquid crystal phase temperature) is equal to or higher than the temperature at which the crosslinkable liquid crystal becomes the isotropic phase (liquid phase).

  In addition, the polymerization (crosslinking polymerization) between the crosslinkable liquid crystal molecules imparted with alignment in the liquid crystal coating film is performed by using light having a photosensitive wavelength such as a cross-linked liquid crystal molecule or a photopolymerization initiator contained in the liquid crystal composition. It can be advanced by irradiating the surface. At this time, the wavelength of light applied to the liquid crystal coating film is appropriately selected according to the absorption wavelength of the liquid crystal composition, but is generally about 200 to 500 nm. The light applied to the liquid crystal coating film is not limited to monochromatic light, and may be light having a certain wavelength range including the photosensitive wavelength of the photopolymerization initiator.

  Thus, when the crosslinkable liquid crystal molecules contained in the liquid crystal coating film are polymerized, the liquid crystal coating film forms the retardation layer 4 and the color filter 1 is manufactured.

  In order to make the liquid crystal coating film into the retardation layer 4, the liquid crystal coating film is irradiated with light to advance the crosslinking polymerization reaction of the crosslinkable liquid crystal molecules, and further, the liquid crystal coating film is baked using an oven or the like. It may be done. By performing such firing, the retardation layer 4 can be further cured, and the color filter 1 in which the surface of the retardation layer 4 is cured can be obtained.

  In the color filter 1, the pencil hardness of the retardation layer 4 is preferably 2H or more according to the evaluation standard of JIS K5600-5-4.

  Here, the pencil hardness of the retardation layer 4 is a value specifically measured by the following test method. First, in this pencil hardness test method, a pencil composed of an elongated cylindrical core and a wood portion surrounding the core is used, and the wood portion is removed from the end of the pencil in the longitudinal direction with a pencil sharpener. The core is exposed about 5 to 6 mm. At this time, care should be taken so that the pencil core is not damaged and a large chip is not formed, so that it becomes a substantially smooth cylindrical shape. Then, the tip of the pencil lead is brought into contact with the abrasive paper perpendicularly, and the pencil is moved back and forth with respect to the abrasive paper while maintaining an angle of about 90 °, thereby keeping the tip of the lead flat. Next, a substrate (sample substrate) serving as a sample whose hardness is to be measured is prepared in advance, and the sample substrate is placed in a pencil hardness tester provided with a pencil whose tip is flattened. The pencil hardness tester is set so that the load is 0 g when the tip of the pencil contacts the sample substrate at an angle of 1 °. Then, a load of 750 ± 10 g is applied to the pencil. After the tip of the pencil is placed on the sample substrate, the sample substrate is moved 7 mm at a speed of 0.5 to 1 mm / s in a direction in which the pencil is inclined at 45 ± 1 °. After the tip of the pencil moves on the surface of the sample substrate, move the pencil on the sample substrate and inspect the condition of the surface (painted surface) part (test part) that was tested with the naked eye to determine the type of pencil indentation. Investigate. Pencil indentation may or may not cause an indentation. When an indentation occurs, it is classified and defined as follows (a) to (c) depending on the situation.

(A) Plastic deformation: Permanent indentation occurs in the coating film on the surface of the sample substrate, but there is no cohesive failure.
(B) Cohesive failure: The coating material used for forming the coating film is peeled off, scratched or broken by the naked eye on the surface of the sample substrate.
(C) Combination of the above: In the final stage, all defects may occur simultaneously.

  If no indentation of any of the above classifications (a), (b), (c) occurs, the test is repeated with the pencil hardness scale raised, and any one of classifications (a), (b), (c) If indentation occurs, lower the pencil hardness scale and repeat the test. However, in such a repeated test, the position where the pencil tip and the sample substrate are brought into contact with each other is set to a different position so as not to overlap each other in each test.

  This pencil hardness test specifies the hardness of a pencil at which a scar having a length of at least 3 mm is generated at a test site. The pencil hardness test is performed twice, and when the result of the two times differs by one unit or more, it is discarded and the test is performed again.

  Thus, in the pencil hardness test, the hardness of the hardest pencil that does not cause any indentation of classification (a), (b), or (c) is specified, and the hardness becomes the pencil hardness.

  In addition, the color filter 1 in which the colored layer 3 is formed between the substrate 2 and the retardation layer 4 is specifically described as an example of the color filter in which the retardation layer is formed using the liquid crystal composition in the present invention. However, the present invention is not limited to this, and the color filter may be one in which a retardation layer 4 is formed between the substrate 2 and the colored layer 3 as shown in FIG.

  As shown in FIGS. 3 and 4, the color filter 1 may be provided with a protective layer 9 and a spacer 10 on the surface of the retardation layer 4 as necessary.

  The protective layer 9 is made of a transparent resin material made of a material such as an acrylic, amide or ester polymer containing a polyfunctional acrylate, or a material such as an acrylic, amide or ester polymer containing a polyfunctional epoxy. A resin composition such as a transparent resin coating can be applied to the surface of the retardation layer 4 to form a resin coating film, and the resin coating film can be dried and further cured. The resin coating film can be cured by appropriately performing a known curing method according to the properties of the resin composition. For example, the resin coating film can be made of a transparent resin material made of an acrylic polymer material containing a polyfunctional acrylate. When the film is formed, the resin coating film can be cured by irradiating the resin coating film with UV light or the like.

  The spacer 10 is formed by applying a photo-curable photosensitive paint made of an acrylic, amide, or ester polymer containing polyfunctional acrylate on the surface of the retardation layer 4 or the protective layer 9. Is dried and exposed through a mask on which a pattern corresponding to a position where the spacer 10 is to be formed (spacer formation scheduled position) is exposed, and then developed to remove the photosensitive paint other than the spacer formation planned position, thereby forming a spacer. It is formed by baking the photosensitive paint left at the predetermined position.

  As shown in FIG. 5, the color filter 1 of the present invention has a liquid crystal material (a driving liquid crystal material 14) between two opposing substrates (a display side substrate 12, a driving circuit side substrate 13 as a driving liquid crystal side substrate). In the liquid crystal display device 11 formed by appropriately arranging the linear deflection plates 23, 32 and the like in the liquid crystal cell 15 formed by forming the drive liquid crystal layer by enclosing the liquid crystal display device), the observer side of the liquid crystal display device 11 ( It can be used as the display-side substrate 12 installed in the upper part of the figure. In the case of the example of FIG. 5, the retardation layer 4 of the color filter 1 is fixed in a state where, for example, the crosslinkable liquid crystal molecules are homeotropically aligned with respect to the transparent substrate 2 (sometimes referred to as a transparent substrate). The positive C plate is formed.

  The driving circuit side substrate 13 includes a driving circuit 33 on the in-cell side of the transparent substrate 31 (side on which the driving liquid crystal material 14 is sealed), and a driving electrode 34 that controls the voltage load. Is provided.

  When the liquid crystal display device 11 is in the IPS mode, the linearly polarizing plate 32 of the display side substrate 12 and the linearly polarizing plate 32 of the driving circuit side substrate 13 are arranged so that their transmission axes are orthogonal to each other. ing.

  Further, in the liquid crystal display device 11, a transparent conductive film 21 is interposed so as to be sandwiched between the display-side substrate 12 and the linear deflection plate 32 as necessary, and a retardation film such as a positive A plate 22 is interposed. 20 may be interposed, and a negative C plate may be further interposed.

  According to the color filter 1 of the present invention, the retardation layer 4 is disposed inside the liquid crystal cell so as to be sandwiched between the transparent substrate 2 of the color filter 1 and the transparent substrate 31 constituting the driving circuit side substrate 13. It is possible to form a liquid crystal display device that is disposed and includes a so-called in-cell type retardation layer 4.

  Next, the retardation layer using the liquid crystal composition of the present invention will be described in detail by taking as an example the case where the liquid crystal molecules contained in the liquid crystal composition are homeotropically aligned to form the retardation layer as a positive C plate. .

Example 1
A mixture of compounds (a) to (d) shown in the following chemical formula 8 is used as a crosslinkable liquid crystal molecule, BHT (2,6-di-tert-butyl-4-hydroxytoluene) as a polymerization inhibitor, and Irgacure 907 as a polymerization initiator. In addition, dodecanol was used as an additive, and these were mixed to prepare a composition (Composition A) having the following composition. Composition A was produced according to the description in JP-T-2004-524385.

Component A of composition A (a) 32.67% by weight
Compound (b) 18.67% by weight
Compound (c) 21.00% by weight
Compound (d) 21.00% by weight
Dodecanol 1.02% by weight
BHT 0.04% by weight
Irgacure 907 5.60% by weight

  With respect to the composition A, pentaerythritol diacrylate monostearate (M-233 manufactured by Toagosei Co., Ltd.), which is a polyfunctional molecule containing an alcoholic hydroxyl group as a polyfunctional molecule, is 5% by weight in terms of the formulation. And further dissolved in propylene glycol monomethyl ether acetate (PGMEA) to obtain a liquid crystal composition having a composition component concentration of 20% by weight. Here, the compounding component concentration indicates the weight ratio of the entire compounding component excluding the solvent with respect to the total weight of the liquid crystal composition.

A glass substrate (manufactured by Corning, 1737 glass) (dimensions: length 100 mm × width 100 mm × thickness 0.7 mm) was set on a spin coater (manufactured by Mikasa, 1H-360S) and obtained on the glass substrate as described above. The liquid crystal composition was spin-coated to form a liquid crystal coating film, which was dried under reduced pressure. Next, the glass substrate on which the liquid crystal coating film was formed was irradiated with ultraviolet rays (365 nm) for 10 seconds at 20 mW / cm ² by an ultraviolet irradiation device having an ultra-high pressure mercury lamp (“TOSCURE 751” manufactured by Harrison Toshiba Lighting Co., Ltd.). The crosslinkable liquid crystal molecules contained in the liquid crystal coating film are cross-linked and polymerized, and then baked at 230 ° C. for 30 minutes using an oven to form the liquid crystal coating film as a retardation layer (film thickness: 1.5 μm). An optical element having a layer was obtained.

  For the retardation layer formed in the obtained optical element, the alignment state and hardness of the crosslinkable liquid crystal molecules were measured.

"Alignment state of crosslinkable liquid crystal molecules (orientation)"
The alignment state of the crosslinkable liquid crystal molecules contained in the retardation layer formed in the optical element was evaluated by measuring the retardation produced when light having a wavelength of 589 nm passed through the retardation layer as follows. The retardation layer was measured using RETS-1250AV manufactured by Otsuka Electronics.

  As shown in FIG. 6, an x-axis and a y-axis that are orthogonal to each other are assumed on the surface of the retardation layer of the optical element, and a z-axis that is perpendicular to the x-axis and the y-axis is assumed. And the phase difference of the optical element was measured about the z-axis direction and the direction inclined in the x-axis direction and the y-axis direction with respect to the z-axis. In addition, when measured in the direction tilted in the x-axis direction, when measured in the direction tilted in the y-axis direction, it is measured whether or not the phase difference generated in the optical element exhibits symmetry with respect to the z-axis. did. Based on these measurement results, the quality of the orientation as to whether or not the crosslinkable liquid crystal molecules are homeotropically oriented was evaluated as follows. The results are shown in Table 1.

The phase difference is symmetrical in both the x-axis direction and the y-axis direction, or the phase difference value in the z-axis direction is 4 nm or less, and either one is satisfied.
The phase difference is disturbed in symmetry in both the x-axis direction and the y-axis direction, and the value of the phase difference in the z-axis direction is larger than 4 nm.

  In addition, regarding the above reference of 4 nm phase difference, when a phase difference is generated between two polarizing plates arranged in crossed Nicols and light is transmitted through the two polarizing plates, visually, The reference value of the phase difference that falls within such a range that light transmission cannot be confirmed is 4 nm.

“Hardness of retardation layer (layer hardness)”
The measurement of the hardness of the retardation layer formed on the optical element was performed by measuring the pencil hardness according to JIS K5600-5-4. The hardness of the retardation layer formed on the obtained optical element was evaluated as follows. The results are shown in Table 1.

Pencil hardness is equivalent to or harder than 2H (pencil hardness is 2H or more)
Pencil hardness is softer than 2H and harder than B or equivalent ...
Pencil hardness is softer than that of B ...

Example 2
Example 1 except that pentaerythritol diacrylate monostearate (M-233 manufactured by Toagosei Co., Ltd.), which is a polyfunctional molecule containing an alcoholic hydroxyl group as a polyfunctional molecule, was used in an amount of 10% by weight in terms of the formulation. Similarly, an optical element having a retardation layer was produced. For the retardation layer of the obtained optical element, the orientation state of the crosslinkable liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

Example 3
An optical element in which a retardation layer is formed in the same manner as in Example 1 except that bisphenol A-glycidyl methacrylate (epoxy ester 3000M manufactured by Kyoeisha Chemical Co., Ltd.), which is a polyfunctional molecule containing an alcoholic hydroxyl group, is used as the polyfunctional molecule. Produced. For the retardation layer of the obtained optical element, the orientation state of the crosslinkable liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

Example 4
An optical element having a retardation layer formed in the same manner as in Example 1 except that pentaerythritol triacrylate (M-305 manufactured by Toagosei Co., Ltd.), which is a polyfunctional molecule containing an alcoholic hydroxyl group, was used as the polyfunctional molecule. did. For the retardation layer of the obtained optical element, the orientation state of the crosslinkable liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

Example 5
Optical in which a retardation layer is formed in the same manner as in Example 1 except that dipentaerythritol hydroxypentaacrylate (SR-399E manufactured by Nippon Kayaku Co., Ltd.), which is a polyfunctional molecule containing an alcoholic hydroxyl group, is used as the polyfunctional molecule. An element was produced. For the retardation layer of the obtained optical element, the orientation state of the crosslinkable liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

Example 6
A retardation layer was formed in the same manner as in Example 1 except that 2-hydroxy 1-3 dimethacryloxypropane (epoxy ester 40EM manufactured by Kyoeisha Chemical Co., Ltd.), which is a polyfunctional molecule containing an alcoholic hydroxyl group, was used as the polyfunctional molecule. The formed optical element was produced. For the retardation layer of the obtained optical element, the orientation state of the crosslinkable liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

Reference example 1
Example, except that pentaerythritol diacrylate monostearate (M-233, manufactured by Toagosei Co., Ltd.), which is a polyfunctional molecule containing an alcoholic hydroxyl group as a polyfunctional molecule, was used in an amount of 3.0% by weight in terms of a compound. The optical element which formed the phase difference layer like 1 was produced. For the retardation layer of the obtained optical element, the orientation state of the crosslinkable liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

Reference example 2
Example 1 except that 25% by weight of pentaerythritol diacrylate monostearate (M-233 manufactured by Toagosei Co., Ltd.), which is a polyfunctional molecule containing an alcoholic hydroxyl group as a polyfunctional molecule, was used in terms of the amount of the compound. Similarly, an optical element having a retardation layer was produced. For the retardation layer of the obtained optical element, the orientation state of the crosslinkable liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

Comparative Example 1
An optical element having a retardation layer was prepared in the same manner as in Example 1 except that no polyfunctional molecule was used. For the retardation layer of the obtained optical element, the orientation state of the crosslinked liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

Comparative Example 2
An optical element having a retardation layer was prepared in the same manner as in Example 1 except that trimethylolpropane triacrylate (Kyoeisha Chemical Co., Ltd., Light Acrylate TMP-A) was used as the polyfunctional molecule. For the retardation layer of the obtained optical element, the orientation state of the crosslinked liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

Comparative Example 3
An optical element having a retardation layer was produced in the same manner as in Example 1 except that pentaerythritol tetraacrylate (light acrylate PE-4A manufactured by Kyoeisha Chemical Co., Ltd.) was used as the polyfunctional molecule. For the retardation layer of the obtained optical element, the orientation state of the crosslinked liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

Comparative Example 4
An optical element having a retardation layer was prepared in the same manner as in Example 1 except that dipentaerythritol hexaacrylate (light acrylate DPE-6A manufactured by Kyoeisha Chemical Co., Ltd.) was used as the polyfunctional molecule. For the retardation layer of the obtained optical element, the orientation state of the crosslinked liquid crystal molecules and the hardness of the retardation layer were measured in the same manner as in Example 1, and the orientation and layer hardness were evaluated. The results are shown in Table 1.

(Table 1)

  According to these examples and comparative examples, according to the liquid crystal composition of the present invention, the retardation layer formed using this liquid crystal composition is maintained while maintaining the orientation of the crosslinked liquid crystal molecules contained in the retardation layer. It can be seen that the hardness of the retardation layer can be improved.

It is a schematic longitudinal cross-sectional view for demonstrating one Example of the color filter using the liquid-crystal composition in this invention. It is a schematic longitudinal cross-sectional view for demonstrating the other Example of the color filter using the liquid-crystal composition in this invention. It is a schematic longitudinal cross-sectional view for demonstrating the other Example of the color filter using the liquid-crystal composition in this invention. It is a schematic longitudinal cross-sectional view for demonstrating the other Example of the color filter using the liquid-crystal composition in this invention. It is a schematic longitudinal cross-sectional view for demonstrating one Example of the liquid crystal display device using the color filter in this invention. It is explanatory drawing for demonstrating the direction which measures the phase difference measurement direction of a phase difference layer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Color filter 2 Board | substrate 3 Colored layer 4 Phase difference layer 5 Black matrix 6, 7, 8 Sub pixel

Claims (12)

  A liquid crystal composition comprising a crosslinkable liquid crystal molecule and a polyfunctional molecule having an alcoholic hydroxyl group and a polymerizable functional group in the molecular structure.   The liquid crystal composition according to claim 1, wherein the crosslinkable liquid crystal molecule has one or more (meth) acryloyl groups in at least one molecule.   The liquid crystal composition according to claim 1 or 2, wherein the polyfunctional molecule is contained in an amount of 5 to 20% by weight in terms of a compound.   The liquid crystal composition according to claim 1, wherein the polyfunctional molecule is a polyfunctional (meth) acrylate.   Polyfunctional (meth) acrylates include 2-hydroxy 1-3 dimethacryloxy propane, 2-hydroxy 1-3 dimethacryloxy propane, 2-hydroxy, 1-acryloxy, 3-methacryloxy propane, ethylene bis [oxy (2 -Hydroxypropane-1,3-diyl)] dimethacrylate, (1-methyl-1,2-ethanediyl) bis [oxy (2-hydroxy-3,1-propanediyl)] diacrylate, bisphenol A-glycidyl methacrylate, The liquid crystal composition according to claim 4, which is selected from bisphenol A-glycidyl acrylate and pentaerythritol diacrylate monostearate.   The liquid crystal composition according to claim 4, wherein the polyfunctional (meth) acrylate is pentaerythritol triacrylate.   The liquid crystal composition according to claim 4, wherein the polyfunctional (meth) acrylate is dipentaerythritol hydroxypentaacrylate.   A colored layer and a retardation layer are laminated on a light-transmitting substrate, and the retardation layer is formed by curing the liquid crystal composition according to claim 1. A color filter characterized by   A phase difference layer irradiates light toward the surface of the liquid crystal coating film with respect to the liquid crystal coating film formed by coating the liquid crystal composition according to claim 1 on the colored layer. The color filter according to claim 8, which is formed by curing the crosslinkable liquid crystal molecules.   The retardation layer contains (meth) acryloyl group at least 94.9 to 70% by weight of the crosslinkable liquid crystal molecules in terms of the compound, and 0.1 to 10% by weight of photopolymerization in terms of the compound. Evaluation is made according to JIS K5600-5-4, which is formed by photocuring and baking a liquid crystal composition containing an initiator and a polyfunctional molecule in an amount of 5 to 20% by weight in terms of a compound, and having a retardation layer having a pencil hardness. The color filter according to claim 8 or 9, wherein the color filter is 2H or more by reference.   The color filter according to claim 8, wherein the crosslinkable liquid crystal molecules contained in the retardation layer are homeotropically aligned.   12. A liquid crystal display device in which a liquid crystal material is sealed between an opposing display side substrate and a driving liquid crystal side substrate to form a driving liquid crystal layer, wherein the display side substrate is according to claim 8. A liquid crystal display device which is a color filter.

Images