Polymerizable liquid crystal composition, optically anisotropic film, laminate, polarizing plate, and image display device

Abstract

To provide an optically anisotropic film capable of suppressing retardation variation due to heat, a laminate, a polarizing plate comprising the optically anisotropic film, and image display device comprising them.SOLUTION: A polymerizable liquid crystal composition containing at least one polymerizable liquid crystal compound is provided, the polymerizable liquid crystal composition containing a polymerizable liquid crystal compound having a ClogP value of 7 or greater and a reactive group-containing non-liquid crystal compound having at least one reactive group selected from an acryloyloxy group and a methacryloyloxy group, in an amount of 3-18 pts.mass with respect to 100 pts.mass of the total polymerizable liquid crystal compounds.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a polymerizable liquid crystal composition, an optically anisotropic film, a laminate including an optically anisotropic layer, and a polarizing plate and an image display device including the optically anisotropic film. [Background technology]

[0002] It is generally known that ion plane switching (IPS) liquid crystal display devices have a large amount of light leakage in black display, and are prone to contrast reduction and color shift when viewed from an oblique direction at an angle of 45 degrees to the absorption axis of the polarizer. This phenomenon occurs because the angle between the absorption axes of the polarizers arranged on the front and back sides of the liquid crystal cell does not appear to be 90 degrees.

[0003] In order to reduce the light leakage when viewed from an oblique direction, a method of disposing a retardation film between a liquid crystal cell and a polarizer has been proposed. For example, Patent Document 1 describes a method of reducing the light leakage of an IPS liquid crystal display device by disposing a stretched retardation film having a refractive index anisotropy of nx>ny>nz and a stretched retardation film having a refractive index anisotropy of nz>nx>ny. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2009-139747 A Summary of the Invention [Problem to be solved by the invention]

[0005] The polarizing plate having a polarizer and a retardation film laminated thereto, as described in Patent Document 1, is suitably used for reducing light leakage from an IPS-type liquid crystal display device. However, in the liquid crystal display device having this configuration, as the use environment of the image display device becomes harsher, there is a demand for further suppression of change in retardation in the retardation layer used.

[0006] The present invention aims to provide a novel solution to the above problems, that is, a new optically anisotropic film made of a novel polymerizable liquid crystal composition. Another object of the present invention is to provide an optically anisotropic film capable of suppressing a change in retardation due to heat, a laminate, a polarizing plate including the optically anisotropic film, and an image display device having the same. [Means for solving the problem]

[0007] The present inventors have conducted extensive research to solve the above problems and have completed the present invention. [1] A polymerizable liquid crystal composition comprising at least one polymerizable liquid crystal compound, the polymerizable liquid crystal composition comprising a polymerizable liquid crystal compound having a ClogP value of 7 or more, and a reactive group-containing non-liquid crystal compound having at least one reactive group selected from an acryloyloxy group and a methacryloyloxy group, in an amount of 3 to 18 parts by mass relative to 100 parts by mass of the total polymerizable liquid crystal compounds. [2] The polymerizable liquid crystal composition according to [1] above, wherein the weight-average molecular weight of the reactive group-containing non-liquid crystal compound is 1,200 or less. [3] The polymerizable liquid crystal composition according to [1] above, further comprising a smectic liquid crystal compound. [4] The polymerizable liquid crystal composition according to [1] above, further comprising a polymerizable liquid crystal compound having a polar group. [5] The polymerizable liquid crystal composition according to [1] above, further comprising a solvent. [6] The polymerizable liquid crystal composition according to [1], further comprising a polymerization initiator. [7] The polymerizable liquid crystal composition according to [1] above, further comprising a leveling agent. [8] An optically anisotropic film obtained by curing the composition of [1] above, which satisfies the following formula (1): O S / O C ≧1.1 (1) [In formula (1), O S is the oxygen atom ratio at 10 nm from the film surface of the optically anisotropic film, and O C represents the oxygen atomic ratio in the central portion of the optically anisotropic film. [9] The optically anisotropic film according to [8] above, which satisfies the following formula (2): nx≒ny <nz (2) [In formula (2), nx represents the principal refractive index in a direction parallel to the film plane in the index ellipsoid formed by the retardation layer. ny represents the refractive index in a direction parallel to the film plane and perpendicular to the direction of nx in the index ellipsoid formed by the retardation layer. nz represents the refractive index in a direction perpendicular to the film plane in the index ellipsoid formed by the retardation layer.)]

[10] The optically anisotropic film according to [8] above, having a thickness of 0.1 μm or more and 3 μm or less.

[11] The optically anisotropic film according to [8] above, which satisfies the following formula (3): -180nm≦RthC(550)≦-30nm (3) [In formula (3), RthC(550) represents a retardation value in the thickness direction at a wavelength of 550 nm.]

[12] The optically anisotropic film according to [8] above, which satisfies the following formula (4): RthC(450) / RthC(550)≧1.04 (4) [In formula (4), RthC(450) represents a retardation value in the thickness direction at a wavelength of 450 nm, and RthC(550) represents a retardation value in the thickness direction at a wavelength of 550 nm.]

[13] A laminate comprising the optically anisotropic film according to [8] above and an optically anisotropic layer.

[14] A polarizing plate comprising a polarizing film and the optically anisotropic film described in [8].

[15] An image display device comprising the polarizing plate according to

[14] above. Effect of the Invention

[0008] According to the present invention, it is possible to provide an optically anisotropic film and laminate that exhibit little change in hue due to heat, a polarizing plate including the laminate, and an image display device having these. [Brief description of the drawings]

[0009] [Figure 1]FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of an optically anisotropic film of the present invention. [Diagram 2] FIG. 1 is a schematic cross-sectional view showing an example of a layer structure of a laminate of the present invention. [Diagram 3] FIG. 1 is a schematic cross-sectional view showing an example of a layer structure of a polarizing plate of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [Polymerizable liquid crystal composition] The polymerizable liquid crystal composition of the present invention contains at least one polymerizable liquid crystal compound, and contains a polymerizable liquid crystal compound having a ClоgP value of 7 or more, and a non-liquid crystal compound having at least one reactive group selected from an acryloyloxy group and a methacryloyloxy group, in an amount of 3 to 18 parts by mass relative to 100 parts by mass of the total polymerizable liquid crystal compounds. In the polymerizable liquid crystal composition of the present invention, "containing at least one polymerizable liquid crystal compound" may mean containing one polymerizable liquid crystal compound having a ClоgP value of 7 or more, may contain two or more polymerizable liquid crystal compounds having a ClоgP value of 7 or more, or may further contain one or a mixture of two or more polymerizable liquid crystal compounds having a ClоgP value of less than 7. It is believed that a polymerizable liquid crystal compound having a ClоgP value of 7 or more is less compatible with a non-liquid crystal compound having at least one reactive group selected from a relatively hydrophilic acryloyloxy group and a methacryloyloxy group, and as a result, promotes the vertical alignment of the polymerizable liquid crystal compound. In order to promote such vertical alignment, it is preferable that a polymerizable liquid crystal compound having a ClоgP value of 7 or more is the main component having the largest weight among the polymerizable liquid crystal compounds in the composition. In terms of promoting vertical alignment, the ClоgP value is preferably 8 or more, more preferably 9 or more, and even more preferably 10 or more. The ClоgP value is usually 15 or less. Here, the ClogP value is a value obtained by calculating the common logarithm logP of the partition coefficient P between 1-octanol and water. Although publicly known methods and software can be used to calculate the ClogP value, unless otherwise specified, in the present invention, the ClogP program incorporated in Cambridgesoft's ChemDraw 22.0 is used.

[0011] As described later in the manufacturing method, the composition of the present invention is cured in a state in which the polymerizable liquid crystal compound is aligned in a direction perpendicular to a plane, and used as a cured product of the polymerizable liquid crystal composition (hereinafter, also referred to as a "vertically aligned liquid crystal cured film").

[0012] Examples of the polymerizable liquid crystal compound include nematic liquid crystal and discotic liquid crystal.

[0013] In the present invention, the polymerizable liquid crystal compound means a liquid crystal compound having a polymerizable group, and examples thereof include nematic liquid crystal and discotic liquid crystal. The polymerizable group refers to a group that can participate in a polymerization reaction by an active radical or an acid generated from a polymerization initiator. Examples of the polymerizable group include a vinyl group, a vinyloxy group, a 1-chlorovinyl group, an isopropenyl group, a 4-vinylphenyl group, an acryloyloxy group, a methacryloyloxy group, an oxiranyl group, and an oxetanyl group. Among them, a radical polymerizable group is preferable, an acryloyloxy group, a methacryloyloxy group, a vinyl group, and a vinyloxy group are more preferable, and an acryloyloxy group and a methacryloyloxy group are even more preferable.

[0014] The liquid crystallinity exhibited by the polymerizable liquid crystal compound may be thermotropic liquid crystal or lyotropic liquid crystal, but thermotropic liquid crystal is preferred in terms of enabling precise control of the film thickness.

[0015] As the polymerizable liquid crystal compound, generally, there are a polymerizable liquid crystal compound exhibiting positive wavelength dispersion and a polymerizable liquid crystal compound exhibiting reverse wavelength dispersion. Only one type of polymerizable liquid crystal compound can be used, or both types of polymerizable liquid crystal compounds can be mixed and used. It is preferable to adjust the composition so that the optically anisotropic film satisfies the following formula (4). RthC(450) / RthC(550)≧1.04 (4) [In formula (5), RthC(450) represents a retardation value in the thickness direction at a wavelength of 450 nm, and RthC(550) represents a retardation value in the thickness direction at a wavelength of 550 nm.]

[0016] In the present invention, as the polymerizable liquid crystal compound having a ClogP value of 7 or more, for example, a compound containing a group represented by the following formula (Y) (hereinafter, also referred to as "polymerizable liquid crystal compound (Y)") may be used. The polymerizable liquid crystal compound (Y) generally tends to exhibit positive wavelength dispersion. The polymerizable liquid crystal compound may be used alone or in combination of two or more kinds.

[0017] P11-B11-E11-B12-A11-B13- (Y) In formula (Y), P11 represents a polymerizable group. A11 represents a divalent alicyclic hydrocarbon group or a divalent aromatic hydrocarbon group. A hydrogen atom contained in the divalent alicyclic hydrocarbon group and the divalent aromatic hydrocarbon group may be substituted with a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, or a nitro group, and a hydrogen atom contained in the alkyl group having 1 to 6 carbon atoms and the alkoxy group having 1 to 6 carbon atoms may be substituted with a fluorine atom. B11 is -O-, -S-, -CO-O-, -O-CO-, -O-CO-O-, -CO-NR 16 -, -NR 16 Represents -CO-, -CO-, -CS- or a single bond. R 16 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. B12 and B13 each independently represent -C≡C-, -CH=CH-, -CH2-CH2-, -O-, -S-, -C(=O)-, -C(=O)-O-, -OC(=O)-, -OC(=O)-O-, -CH=N-, -N=CH-, -N=N-, -C(=O)-NR 16 -, -NR 16 It represents -C(=O)-, -OCH2-, -OCF2-, -CH2O-, -CF2O-, -CH=CH-C(=O)-O-, -OC(=O)-CH=CH- or a single bond. E11 represents an alkanediyl group having 1 to 12 carbon atoms, and a hydrogen atom contained in the alkanediyl group may be substituted with an alkoxy group having 1 to 5 carbon atoms, and a hydrogen atom contained in the alkoxy group may be substituted with a halogen atom. In addition, -CH2- constituting the alkanediyl group may be substituted with -O- or -CO-.]

[0018] The number of carbon atoms in the aromatic hydrocarbon group and alicyclic hydrocarbon group of A11 is preferably in the range of 3 to 18, more preferably in the range of 5 to 12, and particularly preferably 5 or 6. A11 is preferably a cyclohexane-1,4-diyl group or a 1,4-phenylene group.

[0019] E11 is preferably a linear alkanediyl group having 1 to 12 carbon atoms. -CH2- constituting the alkanediyl group may be replaced with -O-. Specific examples include linear alkanediyl groups having 1 to 12 carbon atoms, such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, and a dodecane-1,12-diyl group; -CH2-CH2-O-CH2-CH2-, -CH2-CH2-O-CH2-CH2-O-CH2-CH2-, and -CH2-CH2-O-CH2-CH2-O-CH2-CH2-O-CH2-CH2-. As B11, -O-, -S-, -CO-O-, and -O-CO- are preferable, and among them, -CO-O- is more preferable. As B12 and B13, each independently, -O-, -S-, -C(=O)-, -C(=O)-O-, -OC(=O)- or -OC(=O)-O- is preferable, and among them, -O- or -OC(=O)-O- is more preferable.

[0020] As the polymerizable group represented by P11, a radically polymerizable group or a cationic polymerizable group is preferred from the viewpoint of high polymerization reactivity, particularly high photopolymerization reactivity. In addition, the polymerizable group is preferably a group represented by the following formulae (P-11) to (P-15), since it is easy to handle and the liquid crystal compound can be easily produced.

[0021] [ka] [In formulas (P-11) to (P-15), R 17 ~R 21 each independently represents an alkyl group having 1 to 6 carbon atoms or a hydrogen atom.

[0022] Specific examples of the groups represented by formulae (P-11) to (P-15) include groups represented by the following formulae (P-16) to (P-20).

[0023] [ka]

[0024] P11 is preferably a group represented by formula (P-14) to formula (P-20), and more preferably a vinyl group, a p-stilbene group, an epoxy group or an oxetanyl group. The group represented by P11-B11- is more preferably an acryloyloxy group or a methacryloyloxy group.

[0025] Examples of the polymerizable liquid crystal compound (Y) include compounds represented by formula (I), formula (II), formula (III), formula (IV), formula (V) or formula (VI). P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-A14-B16-E12-B17-P12 (I) P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-A14-F11 (II) P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-E12-B17-P12 (III) P11-B11-E11-B12-A11-B13-A12-B14-A13-F11 (IV) P11-B11-E11-B12-A11-B13-A12-B14-E12-B17-P12 (V) P11-B11-E11-B12-A11-B13-A12-F11 (VI) (In the formula, A12 to A14 each independently have the same meaning as A11, B14 to B16 each independently have the same meaning as B12, B17 has the same meaning as B11, and E12 has the same meaning as E11. F11 represents a hydrogen atom, an alkyl group having 1 to 13 carbon atoms, an alkoxy group having 1 to 13 carbon atoms, a cyano group, a nitro group, a trifluoromethyl group, a dimethylamino group, a hydroxy group, a methylol group, a formyl group, a sulfo group (-SO3H), a carboxy group, an alkoxycarbonyl group having 1 to 10 carbon atoms, or a halogen atom, and -CH2- constituting the alkyl group and the alkoxy group may be replaced with -O-.

[0026] Specific examples of the polymerizable liquid crystal compound (Y) include compounds having a polymerizable group among the compounds described in “3.8.6 Network (completely crosslinked type)” and “6.5.1 Liquid crystal materials b. Polymerizable nematic liquid crystal materials” in Liquid Crystal Handbook (edited by Liquid Crystal Handbook Editorial Committee, published by Maruzen Co., Ltd. on October 30, 2000), and the polymerizable liquid crystals described in JP-A Nos. 2010-31223, 2010-270108, 2011-6360, and 2011-207765.

[0027] Specific examples of the polymerizable liquid crystal compound (Y) include compounds represented by the following formulae (I-1) to (I-10). In the following formulae, k1 and k2 each independently represent an integer of 2 to 12. These polymerizable liquid crystal compounds (Y) are preferred in terms of ease of synthesis or availability.

[0028] [ka]

[0029] In addition to the main component polymerizable liquid crystal compound having a ClogP value of 7 or more, it is preferable to add a smectic liquid crystal compound or a polymerizable liquid crystal compound having a polar group at the end of the structure. Smectic liquid crystal compounds are produced from known compounds described in Lub et al. Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996) and Japanese Patent No. 4719156, and by known methods. Examples of the polar group of the polymerizable liquid crystal compound having a polar group include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a pentafluorosulfuranyl group, a cyano group, a nitro group, an isocyano group, and a thioisocyano group, and preferably a cyano group or an isocyano group.

[0030] The content of the polymerizable liquid crystal compound having a ClogP value of 7 or more in the polymerizable liquid crystal composition is, for example, 30 to 100 parts by mass, preferably 40 to 90 parts by mass, and more preferably 45 to 80 parts by mass, relative to 100 parts by mass of the total polymerizable liquid crystal compounds.

[0031] The content of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition is, for example, 70 to 99.5 parts by mass, preferably 80 to 99 parts by mass, more preferably 85 to 98 parts by mass, and further preferably 90 to 95 parts by mass, based on 100 parts by mass of the solid content of the polymerizable liquid crystal composition. If the content of the polymerizable liquid crystal compound is within the above range, it is advantageous in terms of the alignment of the obtained liquid crystal cured film. In the present invention, the solid content of the polymerizable liquid crystal composition means all components excluding volatile components such as organic solvents from the polymerizable liquid crystal composition.

[0032] In the present invention, the polymerizable liquid crystal composition preferably contains a non-liquid crystal compound having at least one reactive group selected from an acryloyloxy group and a methacryloyloxy group. By containing a reactive group-containing non-liquid crystal compound having at least one reactive group selected from an acryloyloxy group and a methacryloyloxy group, vertical alignment is promoted and the retardation value change after heat resistance test of the obtained liquid crystal cured film can be suppressed.

[0033] Examples of reactive group-containing non-liquid crystal compounds include monofunctional (meth)acrylates and polyfunctional (meth)acrylates. Monofunctional means having one reactive group, and polyfunctional means having multiple reactive groups. In the present invention, the reactive group-containing non-liquid crystal compound constituting the optically anisotropic film is preferably at least one selected from monofunctional (meth)acrylates and polyfunctional (meth)acrylates, more preferably at least one selected from monofunctional acrylates and polyfunctional acrylates, and more preferably polyfunctional acrylates, in that the polymerization reaction between the polymerizable liquid crystal compound and the reactive group-containing non-liquid crystal compound is easily proceeded continuously. As the reactive group-containing non-liquid crystal compound, one type may be used alone, or two or more types may be used in combination. In this specification, (meth)acrylate means acrylate or methacrylate, and the same applies to (meth)acryloyloxy and the like. In addition, since such monofunctional (meth)acrylates and polyfunctional (meth)acrylates are non-liquid crystal, it is preferable that they do not have a mesogen structure. Furthermore, in a coating film of the composition for forming an optically anisotropic film, the polymerizable liquid crystal compound contained therein may contain a urethane structure, an amino structure, an epoxy structure, an ethylene glycol structure, and a polyester structure in the molecule, as long as the liquid crystal phase of the polymerizable liquid crystal compound contained therein is not disturbed.

[0034] A monofunctional (meth)acrylate is a compound having one (meth)acryloyloxy group (i.e., an acryloyloxy group (CH2=CHCOO-) or a methacryloyloxy group (CH2=C(CH3)COO-)) in the molecule.

[0035] Examples of monofunctional (meth)acrylates having one (meth)acryloyloxy group include alkyl (meth)acrylates having 4 to 16 carbon atoms, β-carboxyalkyl (meth)acrylates having 2 to 14 carbon atoms, alkylated phenyl (meth)acrylates having 2 to 14 carbon atoms, methoxypolyethylene glycol (meth)acrylates, phenoxypolyethylene glycol (meth)acrylates, and isobornyl (meth)acrylates.

[0036] A polyfunctional (meth)acrylate is a compound having two or more (meth)acryloyloxy groups in a molecule. In the present invention, the polyfunctional (meth)acrylate used as the reactive group-containing non-liquid crystal compound preferably has 2 to 8 (meth)acryloyloxy groups in a molecule.

[0037] Examples of bifunctional (meth)acrylates having two (meth)acryloyloxy groups include 1,3-butanediol di(meth)acrylate; 1,3-butanediol (meth)acrylate; 1,6-hexanediol di(meth)acrylate; ethylene glycol di(meth)acrylate; diethylene glycol di(meth)acrylate; neopentyl glycol di(meth)acrylate; triethylene glycol di(meth)acrylate; tetraethylene glycol di(meth)acrylate; polyethylene glycol diacrylate; bis(acryloyloxyethyl)ether of bisphenol A; ethoxylated bisphenol A di(meth)acrylate; propoxylated neopentyl glycol di(meth)acrylate; ethoxylated neopentyl glycol di(meth)acrylate and 3-methylpentanediol di(meth)acrylate.

[0038] Examples of polyfunctional (meth)acrylates having 3 to 6 (meth)acryloyloxy groups include: Trimethylolpropane tri(meth)acrylate;Pentaerythritol tri(meth)acrylate;Tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate;Ethoxylated trimethylolpropane tri(meth)acrylate;Propoxylated trimethylolpropane tri(meth)acrylate;Pentaerythritol tetra(meth)acrylate;Dipentaerythritol penta(meth)acrylate;Dipentaerythritol hexa(meth)acrylate;Tripentaerythritol tetra(meth)acrylate;Tripentaerythritol penta(meth)acrylate;Tripentaerythritol hexa(meth)acrylate;Tripentaerythritol hepta(meth)acrylate;Tripentaerythritol octa(meth)acrylate; Reaction products of pentaerythritol tri(meth)acrylate with acid anhydride;Reaction products of dipentaerythritol penta(meth)acrylate with acid anhydride;Reaction products of tripentaerythritol hepta(meth)acrylate with acid anhydride; Caprolactone modified trimethylolpropane tri(meth)acrylate;Caprolactone modified pentaerythritol tri(meth)acrylate;Caprolactone modified tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate;Caprolactone modified pentaerythritol tetra(meth)acrylate;Caprolactone modified dipentaerythritol penta(meth)acrylate;Caprolactone modified dipentaerythritol hexa(meth)acrylate;Caprolactone modified tripentaerythritol tetra(meth)acrylate;Caprolactone modified tripentaerythritol Examples of the acryloyloxy group include caprolactone-modified tripentaerythritol penta(meth)acrylate, caprolactone-modified tripentaerythritol hexa(meth)acrylate, caprolactone-modified tripentaerythritol hepta(meth)acrylate, caprolactone-modified tripentaerythritol octa(meth)acrylate, a reaction product of caprolactone-modified pentaerythritol tri(meth)acrylate and an acid anhydride, a reaction product of caprolactone-modified dipentaerythritol penta(meth)acrylate and an acid anhydride, and a reaction product of caprolactone-modified tripentaerythritol hepta(meth)acrylate and an acid anhydride. The term "caprolactone-modified" means that a ring-opened product or a ring-opened polymer of caprolactone is introduced between the alcohol-derived portion of the (meth)acrylate compound and the (meth)acryloyloxy group.

[0039] Examples of polyfunctional (meth)acrylates having seven or more (meth)acryloyloxy groups include tripentaerythritol hepta(meth)acrylate; tripentaerythritol octa(meth)acrylate; a reaction product of tripentaerythritol hepta(meth)acrylate and an acid anhydride; caprolactone-modified tripentaerythritol hepta(meth)acrylate; caprolactone-modified tripentaerythritol octa(meth)acrylate; a reaction product of caprolactone-modified tripentaerythritol hepta(meth)acrylate and an acid anhydride.

[0040] As the reactive group-containing non-liquid crystal compound, a commercially available polyfunctional (meth)acrylate can also be used. Examples of such commercially available products include A-DOD-N, A-HD-N, A-NOD-N, APG-100, APG-200, APG-400, A-GLY-9E, A-GLY-20E, A-TMM-3, A-TMPT, AD-TMP, ATM-35E, A-TMMT, A-9550, A-DPH, HD-N, NOD-N, NPG, and TMPT (all manufactured by Shin-Nakamura Chemical Co., Ltd.), ARONIX M-220, ARONIX M-325, ARONIX M-240, ARONIX M-270, ARONIX M-309, ARONIX M-310, ARONIX M-321, ARONIX M-350, ARONIX M-360, ARONIX M-305, ARONIX M-306, ARONIX M-450, and ARONIX Examples include M-451, ARONIX M-408, ARONIX M-400, ARONIX M-402, ARONIX M-403, ARONIX M-404, ARONIX M-405, ARONIX M-406 (all manufactured by Toa Gosei Co., Ltd.), EBECRYL11, EBECRYL145, EBECRYL150, EBECRYL40, EBECRYL140, EBECRYL180, DPGDA, HDDA, TPGDA, HPNDA, PETIA, PETRA, TMPTA, TMPEOTA, DPHA, and EBECRYL series (all manufactured by Daicel-Cytec Co., Ltd.).

[0041] Preferred polyfunctional (meth)acrylates include compounds represented by the following formulas (B-1) to (B-14).

[0042] [ka]

[0043] The reactive group-containing non-liquid crystal compound preferably has 2 to 12 reactive groups in the molecule, more preferably has 2 to 12 polymerizable groups in the molecule, and is further preferably a polyfunctional (meth)acrylate having 2 to 12 polymerizable groups in the molecule. From the viewpoint of easier improvement of film strength, the reactive group-containing non-liquid crystal compound has preferably 3 or more reactive groups (polymerizable groups) in one molecule, more preferably 4 or more, and even more preferably 5 or more polymerizable groups. The number of polymerizable groups in the reactive group-containing non-liquid crystal compound is preferably 10 or less, more preferably 9 or less, and even more preferably 8 or less in one molecule.

[0044] In the present invention, it is preferable that the reactive group (polymerizable group) of the reactive group-containing non-liquid crystal compound is the same as the polymerizable group of the polymerizable liquid crystal compound. In addition, when at least one compound selected from the polymerizable liquid crystal compound and the reactive group-containing non-liquid crystal compound has a plurality of reactive groups, it is preferable that at least one polymerizable group of the polymerizable liquid crystal compound is the same as at least one reactive group of the reactive group-containing non-liquid crystal compound. For example, when the reactive group-containing non-liquid crystal compound is a monofunctional (meth)acrylate, it is preferable that the polymerizable liquid crystal compound also has a (meth)acryloyloxy group. When the reactive group-containing non-liquid crystal compound is a polyfunctional (meth)acrylate, it is preferable that the polymerizable liquid crystal compound also has a (meth)acryloyloxy group.

[0045] The content of the reactive group-containing non-liquid crystal compound in the polymerizable liquid crystal composition is 3 parts by mass or more and 18 parts by mass or less with respect to 100 parts by mass of the total polymerizable liquid crystal compounds in the composition. The reactive group-containing non-liquid crystal compound is unlikely to disturb the alignment of the polymerizable liquid crystal compound, and is likely to suppress the change in retardation value after a heat resistance test while having high vertical alignment properties. From the viewpoint of a balance between an appropriate retardation change suppression ability and the alignment order of the polymerizable liquid crystal compound, the content of the reactive group-containing non-liquid crystal compound is more preferably 5 parts by mass or more and more preferably 15 parts by mass or less with respect to 100 parts by mass of the total polymerizable liquid crystal compounds. The weight average molecular weight of the reactive group-containing non-liquid crystal compound is preferably 1200 or less, more preferably 1000 or less, and more preferably 100 or more, more preferably 200 or more. When the weight average molecular weight of the reactive group-containing non-liquid crystal compound is within the above range, it is easy to suppress the change in retardation value after a heat resistance test while having high vertical alignment properties. The weight average molecular weight of the reactive group-containing non-liquid crystal compound can be measured, for example, by gel permeation chromatography (GPC).

[0046] The content of the reactive group-containing non-liquid crystal compound in the optically anisotropic film is preferably 3 parts by mass or more and 18 parts by mass or less with respect to 100 parts by mass of the polymerizable liquid crystal compound constituting the optically anisotropic film. When the content of the reactive group-containing non-liquid crystal compound is within the above range, the reactive group-containing non-liquid crystal compound is unlikely to disturb the alignment of the polymerizable liquid crystal compound, and it is easy to suppress the change in retardation value after heat resistance test while having high vertical alignment property. From the viewpoint of the balance between the moderate retardation change suppression ability and the alignment order of the polymerizable liquid crystal compound, the content of the reactive group-containing non-liquid crystal compound is more preferably 5 parts by mass or more and more preferably 15 parts by mass or less with respect to 100 parts by mass of the polymerizable liquid crystal compound constituting the optically anisotropic film.

[0047] The polymerizable liquid crystal composition used for forming the vertically aligned liquid crystal cured film may further contain, in addition to the polymerizable liquid crystal compound, additives such as a solvent, a polymerization initiator, a leveling agent, an antioxidant, a photosensitizer, etc. Each of these components may be used alone or in combination of two or more.

[0048] The polymerizable liquid crystal composition used for forming the vertically aligned liquid crystal cured film is preferably dissolved in a solvent and applied onto a substrate, a vertically aligned film, etc. The solvent is preferably a solvent capable of dissolving the polymerizable liquid crystal compound, and is preferably a solvent inactive to the polymerization reaction of the polymerizable liquid crystal compound. Examples of the solvent include alcohol solvents such as water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, 1-methoxy-2-propanol, 2-butoxyethanol, and propylene glycol monomethyl ether; ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate, and ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane, and heptane; alicyclic hydrocarbon solvents such as ethylcyclohexane; aromatic hydrocarbon solvents such as toluene and xylene; nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran and dimethoxyethane; chlorine-containing solvents such as chloroform and chlorobenzene; and amide solvents such as dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone (NMP), and 1,3-dimethyl-2-imidazolidinone. These solvents can be used alone or in combination of two or more. Among these, alcohol solvents, ester solvents, ketone solvents, chlorine-containing solvents, amide solvents and aromatic hydrocarbon solvents are preferred.

[0049] The content of the solvent in the polymerizable liquid crystal composition is preferably 50 to 98 parts by weight, more preferably 70 to 95 parts by weight, relative to 100 parts by weight of the polymerizable liquid crystal composition. Therefore, the solid content per 100 parts by weight of the polymerizable liquid crystal composition is preferably 2 to 50 parts by weight. If the solid content is 50 parts by weight or less, the viscosity of the polymerizable liquid crystal composition is low, so that the thickness of the film becomes approximately uniform and unevenness tends to be less likely to occur. The solid content can be appropriately determined in consideration of the thickness of the liquid crystal cured film to be produced.

[0050] The polymerization initiator is a compound that generates reactive species by the contribution of heat or light and can initiate a polymerization reaction of a polymerizable liquid crystal compound, etc. Examples of the reactive species include active species such as radicals, cations, and anions. Among them, a photopolymerization initiator that generates radicals by light irradiation is preferred from the viewpoint of easy reaction control.

[0051] Examples of photopolymerization initiators include benzoin compounds, benzophenone compounds, benzyl ketal compounds, α-hydroxyketone compounds, α-aminoketone compounds, oxime compounds, triazine compounds, iodonium salts, and sulfonium salts.Specific examples include Irgacure (registered trademark) 907, Irgacure 184, Irgacure 651, Irgacure 819, Irgacure 250, Irgacure 369, Irgacure 379, Irgacure 127, Irgacure 2959, Irgacure 754, Irgacure 379EG (all manufactured by BASF Japan Ltd.), Seikuol BZ, Seikuol Z, Seikuol BEE (all manufactured by Seiko Chemical Co., Ltd.), Kayacure (registered trademark) Examples of suitable antibacterial agents include ADEKA CURE BP100 (manufactured by Nippon Kayaku Co., Ltd.), Kayacure UVI-6992 (manufactured by Dow), ADEKA OPTOMER SP-152, ADEKA OPTOMER SP-170, ADEKA OPTOMER N-1717, ADEKA OPTOMER N-1919, ADEKA ARCLES NCI-831, ADEKA ARCLES NCI-930 (all manufactured by ADEKA Corporation), TAZ-A, TAZ-PP (all manufactured by Nippon SiberHegner AG) and TAZ-104 (manufactured by Sanwa Chemical Co., Ltd.).

[0052] The photopolymerization initiator can fully utilize the energy emitted from the light source and has excellent productivity, so that the maximum absorption wavelength is preferably 300 nm to 400 nm, and more preferably 300 nm to 380 nm, and among them, an α-acetophenone-based polymerization initiator or an oxime-based photopolymerization initiator is preferable.

[0053] Examples of α-acetophenone compounds include 2-methyl-2-morpholino-1-(4-methylsulfanylphenyl)propan-1-one, 2-dimethylamino-1-(4-morpholinophenyl)-2-benzylbutan-1-one, and 2-dimethylamino-1-(4-morpholinophenyl)-2-(4-methylphenylmethyl)butan-1-one, and more preferably 2-methyl-2-morpholino-1-(4-methylsulfanylphenyl)propan-1-one and 2-dimethylamino-1-(4-morpholinophenyl)-2-benzylbutan-1-one. Examples of commercially available α-acetophenone compounds include Irgacure 369, 379EG, and 907 (all manufactured by BASF Japan Co., Ltd.) and Seikuol BEE (manufactured by Seiko Chemical Co., Ltd.).

[0054] The oxime-based photopolymerization initiator generates radicals such as phenyl radicals and methyl radicals when irradiated with light. The polymerization of the polymerizable liquid crystal compound proceeds favorably by these radicals, and among them, the oxime-based photopolymerization initiator that generates methyl radicals is preferred in terms of high initiation efficiency of the polymerization reaction. In addition, from the viewpoint of proceeding the polymerization reaction more efficiently, it is preferable to use a photopolymerization initiator that can efficiently utilize ultraviolet light with a wavelength of 350 nm or more. As the photopolymerization initiator that can efficiently utilize ultraviolet light with a wavelength of 350 nm or more, a triazine compound or a carbazole compound containing an oxime structure is preferred, and from the viewpoint of sensitivity, a carbazole compound containing an oxime ester structure is more preferred. Examples of the carbazole compound containing an oxime structure include 1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyloxime)], ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(O-acetyloxime), and the like. Commercially available oxime ester photopolymerization initiators include Irgacure OXE-01, Irgacure OXE-02, Irgacure OXE-03 (all manufactured by BASF Japan Ltd.), ADEKA Optomer N-1919, ADEKA Arcles NCI-831 (all manufactured by ADEKA Corporation), and the like.

[0055] The content of the photopolymerization initiator is usually 0.1 to 30 parts by mass, preferably 1 to 20 parts by mass, and more preferably 1 to 15 parts by mass, based on 100 parts by mass of the polymerizable liquid crystal compound. Within the above range, the reaction of the polymerizable group proceeds sufficiently, and the alignment of the polymerizable liquid crystal compound is unlikely to be disturbed.

[0056] A leveling agent is an additive that has the function of adjusting the fluidity of a polymerizable liquid crystal composition and making the coating film obtained by applying the composition flatter. Examples of the leveling agent include silicone-based, polyacrylate-based and perfluoroalkyl-based leveling agents. As the leveling agent, a commercially available product may be used. Specific examples of the leveling agent include DC3PA, SH7PA, DC11PA, SH28PA, SH29PA, SH30PA, ST80PA, ST86PA, SH8400, SH8700, FZ2123 (all manufactured by Toray Dow Corning Co., Ltd.), KP321, KP323, KP324, KP326, KP340, KP341, X22-161A, KF6001 (all manufactured by Shin-Etsu Chemical Co., Ltd.), TSF400, TSF401, TSF410, TSF4300, TSF4440, TSF4445, TSF-4446, TSF4452, TSF4460 (all manufactured by Momentive Performance Materials Co., Ltd.). Japan LLC), Fluorinert (registered trademark) FC-72, FC-40, FC-43, FC-3283 (all manufactured by Sumitomo 3M Limited), Megafac (registered trademark) R-08, R-30, R-90, F-410, F-411, F-443, F-445, F-470, F-477, F-479, F-482, F-483, F-556 (all manufactured by DIC Corporation), F-top (trade name) EF301, EF3 03, EF351, EF352 (all manufactured by Mitsubishi Materials Electronics Co., Ltd.), Surflon (registered trademark) S-381, S-382, S-383, S-393, SC-101, SC-105, KH-40, SA-100 (all manufactured by AGC Seimi Chemical Co., Ltd.), trade names E1830, E5844 (manufactured by Daikin Fine Chemical Research Institute Co., Ltd.), BM-1000, BM-1100, BYK-352, BYK-353 and BYK-361N (all trade names: manufactured by BM Chemie), etc. The leveling agent can be used alone or in combination of two or more kinds.

[0057] The content of the leveling agent is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, based on 100 parts by mass of the polymerizable liquid crystal compound. When the content of the leveling agent is within the above range, it is easy to align the polymerizable liquid crystal compound, and the obtained liquid crystal cured film tends to be smoother, which is preferable.

[0058] By blending an antioxidant, the polymerization reaction of the polymerizable liquid crystal compound can be controlled. The antioxidant may be a primary antioxidant selected from phenol-based antioxidants, amine-based antioxidants, quinone-based antioxidants, and nitroso-based antioxidants, or a secondary antioxidant selected from phosphorus-based antioxidants and sulfur-based antioxidants. In order to polymerize the polymerizable liquid crystal compound without disturbing the alignment of the polymerizable liquid crystal compound, the content of the antioxidant is usually 0.01 to 10 parts by mass, preferably 0.1 to 5 parts by mass, and more preferably 0.1 to 3 parts by mass, based on 100 parts by mass of the polymerizable liquid crystal compound. The antioxidant may be used alone or in combination of two or more kinds.

[0059] In addition, the photopolymerization initiator can be made highly sensitive by using a photosensitizer. Examples of the photosensitizer include xanthones such as xanthone and thioxanthone; anthracenes having a substituent such as anthracene and alkyl ether; phenothiazine; and rubrene. The photosensitizer can be used alone or in combination of two or more kinds. The content of the photosensitizer is usually 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass, and more preferably 0.1 to 3 parts by mass, based on 100 parts by mass of the polymerizable liquid crystal compound.

[0060] The polymerizable liquid crystal composition used for forming the vertically aligned liquid crystal cured film can be obtained by stirring the polymerizable liquid crystal compound, a solvent, a photopolymerization initiator, and components other than the polymerizable liquid crystal compound at a predetermined temperature.

[0061] [Optical anisotropic film] The optically anisotropic film of the present invention will be described below with reference to FIG. 1, but the present invention is not limited to these embodiments. The optically anisotropic film of the present invention preferably satisfies the following formula (1). O S / O C ≧1.1 (1) [In formula (1), O S is the oxygen atom ratio at 10 nm from the film surface of the optically anisotropic film, and O C represents the oxygen atomic ratio in the central portion of the optically anisotropic film.

[0062] When the optically anisotropic film satisfies the formula (1), the optically anisotropic film exhibits the characteristic that a compound having an O element is segregated on the film surface. Such an optically anisotropic film is excellent in heat resistance and retardation change after a heat resistance test. S / O C The value of is preferably 1.15 or more, more preferably 1.2 or more, and is usually 2.5 or less, preferably 2.0 or less, more preferably 1.8 or less. S / O C If the value is within the above range, it is possible to obtain a laminate in which the change in retardation when the optically anisotropic film is subjected to a heat resistance test is suppressed.

[0063] In addition, the optically anisotropic film preferably satisfies the following formula (2). nx≒ny <nz (2) [In formula (3), nx represents the principal refractive index in a direction parallel to the film plane in the index ellipsoid formed by the retardation layer. ny represents the refractive index in a direction parallel to the film plane and perpendicular to the direction of nx in the index ellipsoid formed by the retardation layer. nz represents the refractive index in a direction perpendicular to the film plane in the index ellipsoid formed by the retardation layer.)]

[0064] The thickness of the optically anisotropic film is usually 0.1 μm to 3 μm, preferably 0.3 μm to 2 μm, and more preferably 0.5 μm to 1.5 μm. When the thickness of the optically anisotropic film satisfies the above range, it is possible to achieve both weight reduction and optical properties of the image display device.

[0065] The in-plane retardation value Re(550) of the optically anisotropic film is usually in the range of 0 to 10 nm, and preferably in the range of 0 to 5 nm. Moreover, it is preferable that the retardation value in the thickness direction satisfies the following formula (3). -180nm≦RthC(550)≦-30nm (3) [In formula (4), RthC(550) represents a retardation value in the thickness direction at a wavelength of 550 nm.]

[0066] [Optical anisotropic layer] The optically anisotropic film of the present application is preferably used in combination with an optically anisotropic layer other than the optically anisotropic film. Examples of the optically anisotropic layer include a stretched film or a cured layer of a polymerizable liquid crystal composition in which a polymerizable liquid crystal compound is cured in a state where the polymerizable liquid crystal compound is aligned in the horizontal direction relative to the film plane.

[0067] Examples of stretched films include uniaxially stretched polycarbonate (PC) films, uniaxially stretched triacetyl cellulose (TAC) films, and uniaxially stretched cycloolefin polymer (COP) films. The in-plane retardation values ​​of these stretched films can be adjusted by controlling the composition of the resin constituting the stretched film, the stretching method, and the thickness of the stretched film.

[0068] The thickness of the optically anisotropic layer is preferably 0.5 μm or more and 5 μm or less, more preferably 0.6 μm or more and 4.5 μm or less, and even more preferably 0.7 μm or more and 4 μm or less. Since a thinner thickness is preferable, as described below, the optically anisotropic layer is preferably a cured product of a polymerizable liquid crystal composition cured in a state where the polymerizable liquid crystal compound is aligned in the horizontal direction relative to the film plane (hereinafter, also referred to as a "horizontally aligned liquid crystal cured film"), and more preferably a liquid crystal cured film obtained by curing a polymerizable liquid crystal compound having at least one radical polymerizable group in a state where the polymerizable liquid crystal compound is aligned horizontally relative to the in-plane direction of the cured film. By using a horizontally aligned liquid crystal cured film having a thickness of the optically anisotropic layer satisfying the above range, it is possible to achieve a reduction in weight of the image display device.

[0069] The polymerizable liquid crystal compound constituting the horizontally aligned liquid crystal cured film is not particularly limited, and for example, a polymerizable liquid crystal compound conventionally known in the field of retardation films can be used. Specifically, the polymerizable liquid crystal compound (X) or the polymerizable liquid crystal compound (Y) exemplified as the polymerizable liquid crystal compound usable for forming the horizontally aligned liquid crystal cured film can be used, and among them, it is preferable to include at least one polymerizable liquid crystal compound exhibiting so-called reverse wavelength dispersion, and for example, the polymerizable liquid crystal compound (X) can be suitably used. In the polymerizable liquid crystal composition for forming the horizontally aligned liquid crystal cured film, the polymerizable liquid crystal compound can be used alone or in combination of two or more kinds, and the polymerizable liquid crystal compound (X) and the polymerizable liquid crystal compound (Y) may be used in combination.

[0070] The content of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition used for forming the horizontally aligned liquid crystal cured film is, for example, 70 to 99.5 parts by mass, preferably 80 to 99 parts by mass, more preferably 85 to 98 parts by mass, and further preferably 90 to 95 parts by mass, relative to 100 parts by mass of the solid content of the polymerizable liquid crystal composition. If the content of the polymerizable liquid crystal compound is within the above range, it is advantageous from the viewpoint of the alignment of the obtained liquid crystal cured film.

[0071] The polymerizable liquid crystal composition used for forming the horizontally aligned liquid crystal cured film may further contain additives such as a solvent, a polymerization initiator, a leveling agent, an antioxidant, a photosensitizer, etc., in addition to the polymerizable liquid crystal compound. Examples of these components include the same ones as those exemplified above as components that can be used in the vertically aligned liquid crystal cured film, and each of them may be used alone or in combination of two or more.

[0072] The polymerizable liquid crystal composition used for forming the horizontally aligned liquid crystal cured film can be obtained by stirring the polymerizable liquid crystal compound and components other than the polymerizable liquid crystal compound, such as a solvent and a photopolymerization initiator, at a predetermined temperature.

[0073] [Method for producing laminate] The laminate of the present invention includes an optically anisotropic film and an optically anisotropic layer. In one embodiment of the present invention, when the optically anisotropic film of the present invention and an optically anisotropic layer are laminated, as illustrated in FIG. 2, a laminate including an optically anisotropic film 1 and an optically anisotropic layer 2 in this order becomes a laminate 10. As the optically anisotropic film, for example, a cured product of a polymerizable liquid crystal composition in which a polymerizable liquid crystal compound is cured in a state where it is aligned in a vertical direction relative to the film plane (vertically aligned liquid crystal cured film) can be used. As the optically anisotropic layer, as described above, for example, a stretched film or a cured product layer of a polymerizable liquid crystal composition in which a polymerizable liquid crystal compound is cured in a state where it is aligned in a horizontal direction relative to the film plane (horizontally aligned liquid crystal cured film) can be used.

[0074] The laminate of the present invention is, for example, A laminate having an optically anisotropic film directly on an optically anisotropic layer can be produced by forming a coating film of a polymerizable liquid crystal composition for forming a vertically aligned liquid crystal cured film, which contains a polymerizable liquid crystal compound, on a stretched film, and forming a vertically aligned liquid crystal cured film from the coating film (hereinafter also referred to as the "vertically aligned liquid crystal cured film forming process").

[0075] The laminate of the present invention is, for example, A laminate having an optically anisotropic layer and a direct optically anisotropic film can be produced by a method including, in this order, a step of forming a coating film of a polymerizable liquid crystal composition for forming a horizontally aligned liquid crystal cured film, which contains a polymerizable liquid crystal compound, and forming a horizontally aligned liquid crystal cured film from the coating film (hereinafter also referred to as a "horizontally aligned liquid crystal cured film forming step"), and a vertically aligned liquid crystal cured film forming step.

[0076] In the laminate of the present invention, when the optically anisotropic layer X is formed of a horizontally aligned liquid crystal cured film, It is preferable to include a step of forming a coating film of a composition for forming a horizontal alignment film and forming a horizontal alignment film from the coating film (hereinafter, also referred to as a "horizontal alignment film forming step") before forming the horizontal alignment film cured film, and it is preferable that the horizontal alignment film forming step and the horizontal alignment liquid crystal cured film forming step are performed continuously in this order. By the manufacturing method including the horizontal alignment film forming step, an optically anisotropic layer X consisting of a horizontal alignment liquid crystal cured film formed on a horizontal alignment film is obtained.

[0077] In the horizontally aligned liquid crystal cured film forming step, the horizontally aligned liquid crystal cured film is, for example, A step of applying a polymerizable liquid crystal composition for forming a horizontally aligned liquid crystal cured film onto a substrate or an alignment film to obtain a coating film; drying the coating to form a dry coating; and A process of irradiating the dried coating with active energy rays to form a horizontally aligned liquid crystal cured film. The composition can be produced by a method comprising the steps of:

[0078] The formation of a coating film of the polymerizable liquid crystal composition can be carried out, for example, by applying the polymerizable liquid crystal composition for forming a horizontally aligned liquid crystal cured film onto a substrate or an alignment film described below. Examples of the substrate include glass substrates and film substrates, but resin film substrates are preferred from the viewpoint of processability. Examples of the resin constituting the film substrate include polyolefins such as polyethylene, polypropylene, and norbornene-based polymers; cyclic olefin resins; polyvinyl alcohol; polyethylene terephthalate; polymethacrylic acid esters; polyacrylic acid esters; cellulose esters such as triacetyl cellulose, diacetyl cellulose, and cellulose acetate propionate; polyethylene naphthalate; polycarbonate; polysulfone; polyether sulfone; polyether ketone; plastics such as polyphenylene sulfide and polyphenylene oxide. Such resins can be formed into a film by known means such as solvent casting and melt extrusion to form a substrate. The substrate surface may have a protective layer formed from an acrylic resin, a methacrylic resin, an epoxy resin, an oxetane resin, a urethane resin, a melamine resin, or the like, and may be subjected to a surface treatment such as a release treatment such as silicone treatment, a corona treatment, or a plasma treatment.

[0079] Commercially available products may be used as the substrate. Examples of commercially available cellulose ester substrates include cellulose ester substrates manufactured by Fuji Photo Film Co., Ltd., such as Fujitac Film; cellulose ester substrates manufactured by Konica Minolta Opto Co., Ltd., such as "KC8UX2M", "KC8UY", and "KC4UY". Examples of commercially available cyclic olefin resins include cyclic olefin resins manufactured by Ticona (Germany), such as "Topas (registered trademark)", cyclic olefin resins manufactured by JSR Corporation, such as "Arton (registered trademark)", cyclic olefin resins manufactured by Zeon Corporation, such as "ZEONOR (registered trademark)" and "ZEONEX (registered trademark)", and cyclic olefin resins manufactured by Mitsui Chemicals, Inc., such as "Apel" (registered trademark). Commercially available cyclic olefin resin substrates may also be used. Commercially available cyclic olefin resin substrates include cyclic olefin resin substrates manufactured by Sekisui Chemical Co., Ltd., such as "S-Cina (registered trademark)" and "SCA40 (registered trademark)"; cyclic olefin resin substrates manufactured by Optes Inc., such as "ZEONORFILM (registered trademark)"; and cyclic olefin resin substrates manufactured by JSR Corporation, such as "ARTONFILM (registered trademark)."

[0080] From the viewpoints of thinning the laminate, ease of peeling the substrate, and ease of handling the substrate, the thickness of the substrate is usually 5 to 300 μm, and preferably 10 to 150 μm. When the substrate is disposed in the laminate of the present invention, the substrate is preferably optically isotropic from the viewpoint of optical compensation described later. In the present invention, being optically isotropic means that the in-plane retardation value of the substrate is 3 nm or less.

[0081] Examples of a method for applying the polymerizable liquid crystal composition to a substrate or the like include known methods such as application methods such as spin coating, extrusion, gravure coating, die coating, bar coating, and applicator methods, and printing methods such as flexography.

[0082] Next, the solvent is removed by drying or the like to form a dried coating film. Examples of drying methods include natural drying, ventilation drying, heat drying, and reduced pressure drying. In this case, the coating film obtained from the polymerizable liquid crystal composition is heated to dry and remove the solvent from the coating film, and the polymerizable liquid crystal compound can be aligned in a horizontal direction relative to the coating film plane. The heating temperature of the coating film can be appropriately determined in consideration of the materials of the polymerizable liquid crystal compound used and the substrate on which the coating film is formed, but it is usually necessary that the temperature be equal to or higher than the liquid crystal phase transition temperature in order to phase-transition the polymerizable liquid crystal compound to a liquid crystal phase state. In order to make the polymerizable liquid crystal compound horizontally aligned while removing the solvent contained in the polymerizable liquid crystal composition, the composition can be heated to a temperature equal to or higher than the liquid crystal phase transition temperature (smectic phase transition temperature or nematic phase transition temperature) of the polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition. The liquid crystal phase transition temperature can be measured using, for example, a polarizing microscope equipped with a temperature control stage, a differential scanning calorimeter (DSC), a thermogravimetric differential thermal analyzer (TG-DTA), etc. When two or more polymerizable liquid crystal compounds are used in combination, the phase transition temperature means a temperature measured in the same manner as when one type of polymerizable liquid crystal compound is used, using a mixture of polymerizable liquid crystal compounds in which all polymerizable liquid crystal compounds constituting the polymerizable liquid crystal composition are mixed in the same ratio as the composition in the polymerizable liquid crystal composition. It is generally known that the liquid crystal phase transition temperature of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition may be lower than the liquid crystal phase transition temperature of the polymerizable liquid crystal compound alone.

[0083] The heating time can be appropriately determined depending on the heating temperature, the type of polymerizable liquid crystal compound used, the type and boiling point of the solvent, and the amount thereof, but is usually 15 seconds to 10 minutes, and preferably 0.5 to 5 minutes.

[0084] The removal of the solvent from the coating film may be performed simultaneously with or separately from the heating of the polymerizable liquid crystal compound to a temperature equal to or higher than the liquid crystal phase transition temperature, but is preferably performed simultaneously from the viewpoint of improving productivity. Before heating the polymerizable liquid crystal compound to a temperature equal to or higher than the liquid crystal phase transition temperature, a preliminary drying step may be provided to adequately remove the solvent in the coating film obtained from the polymerizable liquid crystal composition under conditions in which the polymerizable liquid crystal compound contained in the coating film is not polymerized. Examples of the drying method in the preliminary drying step include natural drying, ventilation drying, heat drying, and reduced pressure drying, and the drying temperature (heating temperature) in the drying step can be appropriately determined depending on the type of polymerizable liquid crystal compound used, the type of solvent, its boiling point, and its amount, etc.

[0085] Next, in the obtained dried coating film, the polymerizable liquid crystal compound is polymerized while maintaining the horizontal alignment state of the polymerizable liquid crystal compound, thereby forming a horizontally aligned liquid crystal cured film. Examples of polymerization methods include thermal polymerization and photopolymerization, but photopolymerization is preferred from the viewpoint of easy control of the polymerization reaction. In photopolymerization, the light irradiated to the dried coating film is appropriately selected according to the type of polymerization initiator contained in the dried coating film, the type of polymerizable liquid crystal compound (particularly, the type of polymerizable group possessed by the polymerizable liquid crystal compound) and the amount thereof. Specific examples thereof include one or more types of light selected from the group consisting of visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays and γ-rays, and active electron beams. Among them, ultraviolet light is preferred in terms of easy control of the progress of the polymerization reaction and the ability to use photopolymerization devices that are widely used in this field, and it is preferable to select the types of polymerizable liquid crystal compound and polymerization initiator contained in the polymerizable liquid crystal composition so that they can be photopolymerized by ultraviolet light. In addition, the polymerization temperature can also be controlled by irradiating light while cooling the dried coating film with an appropriate cooling means during polymerization. By adopting such a cooling means, polymerization of the polymerizable liquid crystal compound can be performed at a lower temperature, and even if a substrate with relatively low heat resistance is used, a horizontally aligned liquid crystal cured film can be appropriately formed. In addition, it is also possible to promote the polymerization reaction by increasing the polymerization temperature within a range in which defects due to heat during light irradiation (such as deformation of the substrate due to heat) do not occur. During photopolymerization, a patterned cured film can also be obtained by performing masking and development.

[0086] Examples of the light source of the active energy rays include a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultra-high pressure mercury lamp, a xenon lamp, a halogen lamp, a carbon arc lamp, a tungsten lamp, a gallium lamp, an excimer laser, an LED light source emitting light in the wavelength range of 380 to 440 nm, a chemical lamp, a black light lamp, a microwave excited mercury lamp, and a metal halide lamp.

[0087] The UV irradiation intensity is usually 10 to 3,000 mW / cm 2 The ultraviolet irradiation intensity is preferably an intensity in a wavelength region effective for activating a photopolymerization initiator. The time for light irradiation is usually 0.1 seconds to 10 minutes, preferably 0.1 seconds to 5 minutes, more preferably 0.1 seconds to 3 minutes, and further preferably 0.1 seconds to 1 minute. When irradiating once or multiple times with such ultraviolet irradiation intensity, the integrated light amount is 10 to 3,000 mJ / cm. 2 , preferably 50 to 2,000 mJ / cm 2 , more preferably 100 to 1,000 mJ / cm 2 It is.

[0088] In the present invention, the coating film of the polymerizable liquid crystal composition for forming the horizontally aligned cured liquid crystal film is preferably formed on a horizontal alignment film having an alignment control force in the horizontal direction with respect to the plane of the obtained liquid crystal cured film, since the degree of alignment order of the horizontally aligned cured liquid crystal film can be increased. Therefore, in the laminate of the present invention, it is preferable that the optically anisotropic layer is formed on the horizontal alignment film, and the horizontal alignment film and the horizontally aligned liquid crystal cured film are included in this order. The alignment control force of the alignment film can be arbitrarily adjusted by the type of alignment film, surface condition, rubbing conditions, etc., and when the alignment film is formed from a photoalignable polymer, it can be arbitrarily adjusted by the polarized light irradiation conditions, etc.

[0089] The horizontal alignment film is preferably one that has solvent resistance such that the polymerizable liquid crystal composition is not dissolved by application or the like, and also has heat resistance in the heat treatment for removing the solvent and for aligning the polymerizable liquid crystal compound described below. Examples of the alignment film include an alignment film containing an alignment polymer, a photo-alignment film, a groove alignment film having a concave-convex pattern or a plurality of grooves on the surface, and a stretched film stretched in the alignment direction, and the like, and a photo-alignment film is preferred from the viewpoint of the accuracy of the alignment angle and the quality.

[0090] Examples of the oriented polymer include polyamides and gelatins having an amide bond in the molecule, polyimides having an imide bond in the molecule, and polyamic acids, which are hydrolyzates thereof, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, polyoxazole, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid, and polyacrylic acid esters. Among them, polyvinyl alcohol is preferred. The oriented polymers can be used alone or in combination of two or more kinds.

[0091] An alignment film containing an alignment polymer is usually obtained by applying a composition in which an alignment polymer is dissolved in a solvent (hereinafter, sometimes referred to as an "alignment polymer composition") to a substrate and removing the solvent, or by applying an alignment polymer composition to a substrate, removing the solvent, and rubbing (rubbing method). Examples of the solvent include the same solvents as those exemplified above as solvents that can be used in the polymerizable liquid crystal composition.

[0092] The concentration of the oriented polymer in the oriented polymer composition may be within a range in which the oriented polymer material can be completely dissolved in the solvent, and is preferably 0.1 to 20% in terms of solid content relative to the solution, and more preferably about 0.1 to 10%.

[0093] As the oriented polymer composition, a commercially available alignment film material may be used as it is. Examples of commercially available alignment film materials include Sunever (registered trademark, manufactured by Nissan Chemical Industries, Ltd.) and Optomer (registered trademark, manufactured by JSR Corporation).

[0094] The method for applying the alignable polymer composition to the substrate may be the same as the above-mentioned example of the method for applying the polymerizable liquid crystal composition to the substrate.

[0095] Methods for removing the solvent contained in the orientable polymer composition include natural drying, ventilation drying, heat drying, and reduced pressure drying.

[0096] In order to impart an orientation control force to the orientation film, a rubbing treatment can be performed as necessary (rubbing method). A method for imparting an orientation control force by the rubbing method includes a method in which an orientation polymer composition is applied to a substrate and annealed to bring an orientation polymer film formed on the substrate surface into contact with a rotating rubbing roll wrapped with a rubbing cloth. If masking is performed during the rubbing treatment, multiple regions (patterns) with different orientation directions can also be formed on the orientation film.

[0097] In a preferred embodiment of the present invention, the horizontal alignment film is a photo-alignment film formed from a polymer having a (meth)acryloyl group. When the horizontal alignment film has a polymerizable group similar to or the same as that of the polymerizable liquid crystal compound constituting the horizontal alignment liquid crystal cured film, the adhesion between the horizontal alignment film and the horizontal alignment liquid crystal cured film tends to be increased, so it is preferable that the horizontal alignment film is formed from a polymer having a (meth)acryloyl group, and the horizontal alignment liquid crystal cured film is formed from a polymerizable liquid crystal composition containing a polymerizable liquid crystal compound having a (meth)acryloyl group.

[0098] A photo-alignment film is usually obtained by applying a composition containing a polymer or monomer having a photoreactive group and a solvent (hereinafter also referred to as a "photo-alignment film forming composition") to a substrate, removing the solvent, and then irradiating the substrate with polarized light (preferably polarized UV). Photo-alignment films are also advantageous in that the direction of the alignment control force can be arbitrarily controlled by selecting the polarization direction of the irradiated polarized light.

[0099] The photoreactive group refers to a group that generates liquid crystal alignment ability by irradiation with light. Specifically, it includes groups involved in photoreactions that induce molecular alignment or are the origin of liquid crystal alignment ability, such as isomerization reaction, dimerization reaction, photocrosslinking reaction, or photodecomposition reaction, caused by irradiation with light. Among them, groups involved in dimerization reaction or photocrosslinking reaction are preferred in terms of excellent alignment ability. As the photoreactive group, a group having an unsaturated bond, particularly a double bond, is preferred, and a group having at least one selected from the group consisting of a carbon-carbon double bond (C=C bond), a carbon-nitrogen double bond (C=N bond), a nitrogen-nitrogen double bond (N=N bond), and a carbon-oxygen double bond (C=O bond) is particularly preferred.

[0100] Examples of photoreactive groups having a C=C bond include vinyl groups, polyene groups, stilbene groups, stilbazole groups, stilbazolium groups, chalcone groups, and cinnamoyl groups. Examples of photoreactive groups having a C=N bond include groups having structures such as aromatic Schiff bases and aromatic hydrazones. Examples of photoreactive groups having an N=N bond include azobenzene groups, azonaphthalene groups, aromatic heterocyclic azo groups, bisazo groups, formazan groups, and groups having an azoxybenzene structure. Examples of photoreactive groups having a C=O bond include benzophenone groups, coumarin groups, anthraquinone groups, and maleimide groups. These groups may have substituents such as alkyl groups, alkoxy groups, aryl groups, allyloxy groups, cyano groups, alkoxycarbonyl groups, hydroxyl groups, sulfonic acid groups, and halogenated alkyl groups.

[0101] Among them, photoreactive groups involved in photodimerization reaction are preferred, and azo groups, cinnamoyl groups, and chalcone groups are preferred in that the amount of polarized light irradiation required for photoalignment is relatively small and a photoalignment film excellent in thermal stability and stability over time is easily obtained. As the polymer having a photoreactive group, a polymer having an azo group or a cinnamoyl group is preferred, and a polymer having a cinnamoyl group such that the terminal of the polymer side chain has a cinnamic acid structure is particularly preferred from the viewpoint of improving adhesion between the horizontal alignment film and the horizontal alignment liquid crystal cured film.

[0102] A photo-alignment layer can be formed on a substrate by applying the composition for forming a photo-alignment film on the substrate. The solvent contained in the composition can be the same as the solvents exemplified above as the solvents usable for the polymerizable liquid crystal composition, and can be appropriately selected depending on the solubility of the polymer or monomer having a photoreactive group.

[0103] The content of the polymer or monomer having a photoreactive group in the composition for forming a photo-alignment film can be appropriately adjusted depending on the type of polymer or monomer and the thickness of the intended photo-alignment film, but is preferably at least 0.2% by mass, more preferably in the range of 0.3 to 10% by mass, based on the mass of the composition for forming a photo-alignment film. The composition for forming a photo-alignment film may contain a polymer material such as polyvinyl alcohol or polyimide, or a photosensitizer, within a range that does not significantly impair the properties of the photo-alignment film.

[0104] The method of applying the composition for forming a photo-alignment film to a substrate may be the same as the method of applying the oriented polymer composition to a substrate. Examples of the method of removing the solvent from the applied composition for forming a photo-alignment film include natural drying, ventilation drying, heat drying, and reduced pressure drying.

[0105] The polarized light may be irradiated by directly irradiating the polarized UV light onto the composition for forming a photo-aligned film coated on the substrate after removing the solvent, or by irradiating the polarized light from the substrate side and transmitting the polarized light. In addition, it is particularly preferable that the polarized light is substantially parallel light. The wavelength of the polarized light to be irradiated is preferably in a wavelength range in which the photoreactive group of the polymer or monomer having a photoreactive group can absorb light energy. Specifically, UV (ultraviolet light) having a wavelength of 250 to 400 nm is particularly preferable. Examples of light sources used for the polarized light irradiation include xenon lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, ultraviolet lasers such as KrF and ArF, and high-pressure mercury lamps, ultra-high-pressure mercury lamps, and metal halide lamps are more preferable. Among these, high-pressure mercury lamps, ultra-high-pressure mercury lamps, and metal halide lamps are preferable because they have a high emission intensity of ultraviolet light with a wavelength of 313 nm. The light from the light source can be irradiated by passing through an appropriate polarizer to irradiate the polarized UV light. As such a polarizer, a polarizing filter, a polarizing prism such as a Glan-Thompson or Glan-Taylor type polarizer, or a wire grid type polarizer can be used.

[0106] If masking is performed during rubbing or polarized light irradiation, a plurality of regions (patterns) in which the liquid crystal alignment directions are different can be formed.

[0107] A groove alignment film is a film that has a concave-convex pattern or multiple grooves on the film surface. When a polymerizable liquid crystal compound is applied to a film with multiple equally spaced linear grooves, the liquid crystal molecules are aligned in the direction along the grooves.

[0108] Methods for obtaining a groove alignment film include a method in which the surface of a photosensitive polyimide film is exposed to light through an exposure mask having slits in a pattern shape, followed by development and rinsing to form an uneven pattern; a method in which a layer of uncured UV-curable resin is formed on a plate-shaped master having grooves on its surface, the formed resin layer is transferred to a substrate and then cured; and a method in which a roll-shaped master having multiple grooves is pressed against an uncured UV-curable resin film formed on a substrate to form unevenness, followed by curing.

[0109] The thickness of the alignment film (alignment film containing an alignment polymer or photoalignment film) is usually 100 to 5000 nm, preferably 100 to 1000 nm, more preferably 100 to 500 nm, further preferably 100 to 300 nm, and particularly preferably 100 to 250 nm. When the thickness of the alignment film is within the above range, it has sufficient horizontal alignment control power, and the alignment film in the laminate is less likely to suffer from cohesive failure.

[0110] When the optically anisotropic film in the laminate of the present invention is formed of a vertically aligned liquid crystal cured film, In the vertical alignment liquid crystal cured film forming step, the vertical alignment liquid crystal cured film is, for example, A step of applying a polymerizable liquid crystal composition for forming a vertically aligned liquid crystal cured film onto a stretched film (optically anisotropic layer) to obtain a coating film; drying the coating to form a dry coating; and A process of irradiating the dried coating with active energy rays to form a vertically aligned liquid crystal cured film. It is possible to produce a laminate having an optically anisotropic film directly on an optically anisotropic layer by the method comprising the steps of:

[0111] The formation of the coating film of the polymerizable liquid crystal composition can be carried out, for example, by coating the polymerizable liquid crystal composition for forming a vertically aligned liquid crystal cured film on a stretched film. The coating method of the polymerizable liquid crystal composition can be the same as the method that can be adopted in the production method of the horizontally aligned liquid crystal cured film.

[0112] In the vertical alignment liquid crystal cured film forming step, the vertical alignment liquid crystal cured film is, for example, A step of applying a polymerizable liquid crystal composition for forming a vertically aligned liquid crystal cured film onto the horizontally aligned liquid crystal cured film to obtain a coating film; drying the coating to form a dry coating; and A process of irradiating the dried coating with active energy rays to form a vertically aligned liquid crystal cured film. It is possible to produce a laminate having an optically anisotropic film directly on an optically anisotropic layer by the method comprising the steps of:

[0113] The formation of a coating film of the polymerizable liquid crystal composition can be carried out, for example, by coating a polymerizable liquid crystal composition for forming a vertically aligned liquid crystal cured film on a horizontally aligned liquid crystal cured film. Examples of a method for coating the polymerizable liquid crystal composition include the same methods as those that can be adopted in the method for producing a horizontally aligned liquid crystal cured film.

[0114] The coating film of the polymerizable liquid crystal composition can be formed, for example, by applying the polymerizable liquid crystal composition for forming a vertically aligned liquid crystal cured film onto the above-mentioned substrate. As the substrate, those exemplified in the method for producing a horizontally aligned liquid crystal cured film can be used. When the substrate is disposed in the laminate of the present invention, the substrate is preferably optically isotropic from the viewpoint of optical compensation described later. In the present invention, being optically isotropic means that the in-plane retardation value of the substrate is 3 nm or less.

[0115] In the laminate of the present invention, the horizontally aligned liquid crystal cured film and the vertically aligned liquid crystal cured film may be laminated via another layer, as long as the effect of the present invention is not affected. Such another layer may be, for example, an adhesive layer. When the laminate of the present invention includes an adhesive layer, the thickness of the adhesive layer is preferably 0.1 to 30 μm, more preferably 0.5 to 20 μm.

[0116] Examples of the adhesive layer include pressure-sensitive adhesives and energy ray curable adhesives. Among these, acrylic adhesives, epoxy adhesives, and urethane adhesives are preferred because they have high transparency and excellent heat resistance.

[0117] The laminate of the present invention may also include, as the other layer, a cured resin layer or a hard coat layer intended to increase or reinforce the mechanical strength of the liquid crystal cured film. When the laminate of the present invention includes the other layer between the horizontally aligned liquid crystal cured film and the vertically aligned liquid crystal cured film, the thickness of the other layer is preferably 0.1 to 4 μm, more preferably 0.5 to 3 μm. When the laminate of the present invention includes the other layer between the horizontally aligned liquid crystal cured film and the vertically aligned liquid crystal cured film, the other layer may be formed after the horizontally aligned liquid crystal cured film is formed, and then a coating film of a polymerizable liquid crystal composition for forming a vertically aligned liquid crystal cured film may be formed on the other layer.

[0118] The cured resin layer can be formed from, for example, an acrylic resin, a methacrylic resin, an epoxy resin, an oxetane resin, a urethane resin, a melamine resin, etc. By providing the cured resin layer, even if the liquid crystal cured film formed adjacent to the cured resin layer is thin, the cured resin layer can sufficiently compensate for the strength of the liquid crystal cured film as a protective layer or a reinforcing layer.

[0119] After the coating film of the polymerizable liquid crystal composition is formed, the solvent is removed by drying or the like to form a dried coating film. Examples of the drying method include natural drying, ventilation drying, heat drying, and reduced pressure drying. From the viewpoint of productivity, heat drying is preferred, and the heating temperature in this case is preferably such that the solvent can be removed and is equal to or higher than the phase transition temperature of the polymerizable liquid crystal compound. The procedure and conditions in this step may be the same as those that can be adopted in the manufacturing method of the horizontally aligned liquid crystal cured film.

[0120] The obtained dried coating film is irradiated with active energy rays (more specifically, ultraviolet rays, etc.) to polymerize the polymerizable liquid crystal compound while maintaining the state in which the polymerizable liquid crystal compound is aligned in the vertical direction relative to the coating film plane, thereby forming a vertically aligned liquid crystal cured film. As the polymerization method, a method similar to the method that can be adopted in the manufacturing method of the horizontally aligned liquid crystal cured film can be used.

[0121] The laminate of the present invention may be a laminate in which an optically anisotropic layer is disposed on an optically anisotropic film. A laminate having an optically anisotropic layer disposed on an optically anisotropic film is A step of applying a polymerizable liquid crystal composition for forming a vertically aligned liquid crystal cured film onto a substrate to obtain a coating film; drying the coating film to form a dry coating film; A step of irradiating the dried coating film with active energy rays to form a vertically aligned liquid crystal cured film; A step of applying a polymerizable liquid crystal composition for forming a horizontally aligned liquid crystal cured film onto the vertically aligned liquid crystal cured film to obtain a coating film; drying the coating to form a dry coating; and A step of irradiating the dried coating film with active energy rays to form a horizontally aligned liquid crystal cured film; It can be produced by a method comprising the steps of:

[0122] In the laminate of the present invention, when an optically anisotropic layer is formed on the optically anisotropic film, it is preferable to include a step of forming a horizontal alignment film by a horizontal alignment film forming step before forming the horizontal alignment liquid crystal cured film. Here, the horizontal alignment film forming step can be the same step as the method exemplified in the horizontal alignment liquid crystal cured film forming step described above.

[0123] [Polarizing Plate] The present invention includes a polarizing plate comprising the optically anisotropic film of the present invention and a polarizing film. The polarizing film is a film having a polarizing function, and examples of the polarizing film include a stretched film having a dye having anisotropic absorption adsorbed thereon, a film coated with a dye having anisotropic absorption as a polarizer, etc. Examples of the dye having anisotropic absorption include a dichroic dye.

[0124] A film including, as a polarizer, a stretched film having adsorbed thereon a dye having absorption anisotropy is usually produced by uniaxially stretching a polyvinyl alcohol-based resin film, dyeing the polyvinyl alcohol-based resin film with a dichroic dye to adsorb the dichroic dye, treating the polyvinyl alcohol-based resin film having the adsorbed dichroic dye with an aqueous boric acid solution, and washing the film with water after the treatment with the aqueous boric acid solution, and then sandwiching the film between a transparent protective film via an adhesive on at least one surface of the polarizer produced through these steps.

[0125] Polyvinyl alcohol resins are obtained by saponifying polyvinyl acetate resins. As polyvinyl acetate resins, in addition to polyvinyl acetate, which is a homopolymer of vinyl acetate, copolymers of vinyl acetate and other monomers copolymerizable therewith are used. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having an ammonium group.

[0126] The degree of saponification of the polyvinyl alcohol resin is usually about 85 to 100 mol%, preferably 98 mol% or more. The polyvinyl alcohol resin may be modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes can also be used. The degree of polymerization of the polyvinyl alcohol resin is usually about 1,000 to 10,000, preferably in the range of 1,500 to 5,000.

[0127] Such a polyvinyl alcohol-based resin is used as a raw film for a polarizing film. The method for forming a film of the polyvinyl alcohol-based resin is not particularly limited, and the film can be formed by a known method. The thickness of the polyvinyl alcohol-based raw film can be, for example, about 10 to 150 μm.

[0128] The uniaxial stretching of the polyvinyl alcohol-based resin film can be performed before, simultaneously with, or after dyeing with a dichroic dye. When the uniaxial stretching is performed after dyeing, the uniaxial stretching may be performed before or during the boric acid treatment. It is also possible to perform the uniaxial stretching at these multiple stages. In the uniaxial stretching, the film may be uniaxially stretched between rolls having different peripheral speeds, or may be uniaxially stretched using a heated roll. The uniaxial stretching may be dry stretching in which the film is stretched in the air, or wet stretching in which the polyvinyl alcohol-based resin film is stretched in a swollen state using a solvent. The stretching ratio is usually about 3 to 8 times.

[0129] Dyeing of a polyvinyl alcohol-based resin film with a dichroic dye is carried out, for example, by a method of immersing the polyvinyl alcohol-based resin film in an aqueous solution containing the dichroic dye.

[0130] Specifically, iodine or a dichroic organic dye is used as the dichroic pigment. Examples of the dichroic organic dye include a dichroic direct dye made of a disazo compound such as CIDIRECT RED 39, and a dichroic direct dye made of a compound such as trisazo or tetrakisazo. It is preferable that the polyvinyl alcohol resin film is immersed in water before the dyeing process.

[0131] When iodine is used as the dichroic dye, a method of dyeing a polyvinyl alcohol resin film by immersing it in an aqueous solution containing iodine and potassium iodide is usually adopted. The content of iodine in this aqueous solution is usually about 0.01 to 1 part by mass per 100 parts by mass of water. The content of potassium iodide is usually about 0.5 to 20 parts by mass per 100 parts by mass of water. The temperature of the aqueous solution used for dyeing is usually about 20 to 40°C. The immersion time in this aqueous solution (dyeing time) is usually about 20 to 1,800 seconds.

[0132] On the other hand, when a dichroic organic dye is used as the dichroic pigment, a method of dyeing a polyvinyl alcohol resin film by immersing it in an aqueous solution containing a water-soluble dichroic dye is usually adopted. The content of the dichroic organic dye in this aqueous solution is usually 1×10 -4 ~10 parts by mass, preferably 1 × 10 -3 ~1 part by mass, more preferably 1 × 10 -3 ~1×10 -2 The amount of the dye in the aqueous solution is expressed by parts by mass. This aqueous solution may contain an inorganic salt such as sodium sulfate as a dyeing assistant. The temperature of the aqueous dichroic dye solution used for dyeing is usually about 20 to 80° C. The immersion time in the aqueous solution (dyeing time) is usually about 10 to 1,800 seconds.

[0133] The boric acid treatment after dyeing with a dichroic dye can usually be carried out by immersing the dyed polyvinyl alcohol resin film in an aqueous boric acid solution. The content of boric acid in this aqueous boric acid solution is usually about 2 to 15 parts by mass, preferably 5 to 12 parts by mass, per 100 parts by mass of water. When iodine is used as the dichroic dye, this aqueous boric acid solution preferably contains potassium iodide, and in this case, the content of potassium iodide is usually about 0.1 to 15 parts by mass, preferably 5 to 12 parts by mass, per 100 parts by mass of water. The immersion time in the aqueous boric acid solution is usually about 60 to 1,200 seconds, preferably 150 to 600 seconds, and more preferably 200 to 400 seconds. The temperature of the boric acid treatment is usually 50°C or higher, preferably 50 to 85°C, and more preferably 60 to 80°C.

[0134] The polyvinyl alcohol-based resin film after the boric acid treatment is usually washed with water. The washing can be performed, for example, by immersing the boric acid-treated polyvinyl alcohol-based resin film in water. The temperature of the water used in the washing is usually about 5 to 40° C. The immersion time is usually about 1 to 120 seconds.

[0135] After washing with water, a drying treatment is carried out to obtain a polarizer. The drying treatment can be carried out, for example, using a hot air dryer or a far-infrared heater. The temperature of the drying treatment is usually about 30 to 100°C, and preferably 50 to 80°C. The time of the drying treatment is usually about 60 to 600 seconds, and preferably 120 to 600 seconds. The moisture content of the polarizer is reduced to a practical level by the drying treatment. The moisture content is usually about 5 to 20 mass%, and preferably 8 to 15 mass%. If the moisture content is less than 5 mass%, the polarizer loses its flexibility, and the polarizer may be damaged or broken after drying. If the moisture content exceeds 20 mass%, the thermal stability of the polarizer may be deteriorated.

[0136] The polyvinyl alcohol-based resin film is then uniaxially stretched, dyed with a dichroic dye, treated with boric acid, washed with water and dried to obtain a polarizer having a thickness of preferably 5 to 40 μm.

[0137] Examples of the film coated with a dye having absorption anisotropy include a film obtained by coating a composition containing a dichroic dye having liquid crystal properties or a composition containing a dichroic dye and a polymerizable liquid crystal. The film preferably has a protective film on one or both sides. Examples of the protective film include the same resin film as the above-mentioned example of a substrate that can be used for producing a horizontally aligned liquid crystal cured film.

[0138] The film coated with the dye having absorption anisotropy is preferably thin, but if it is too thin, the strength decreases and the processability tends to be poor. The thickness of the film is usually 20 μm or less, preferably 5 μm or less, and more preferably 0.5 to 3 μm.

[0139] Specific examples of the film coated with a dye having absorption anisotropy include the films described in JP-A-2012-33249 and the like.

[0140] A transparent protective film may be laminated on at least one surface of the polarizer thus obtained, for example, via an adhesive layer. As the transparent protective film, a transparent film similar to the resin film exemplified above as the substrate usable for producing the liquid crystal cured film can be used.

[0141] The polarizing plate of the present invention is composed of the optically anisotropic film of the present invention and a polarizing film, and can be obtained, for example, by laminating the optically anisotropic film of the present invention and the polarizing film via a pressure-sensitive adhesive layer or the like.

[0142] In one embodiment of the present invention, when the laminate of the present invention and a polarizing film are laminated, a polarizing plate 20 including a polarizing film 3 and an optically anisotropic film (layer 1 in FIG. 3) in this order can be given, as exemplified in FIG. 3. In this case, the polarizing plate of the present invention can be obtained by bonding the optically anisotropic film to the polarizing film 3 via a pressure-sensitive adhesive layer. In the present invention, when an optically anisotropic layer is laminated in addition to the polarizing film and the optically anisotropic film, it is preferable to laminate them so that the angle between the slow axis (optical axis) of the optically anisotropic layer constituting the laminate and the absorption axis of the polarizing film is 90±5°.

[0143] As the adhesive layer for bonding the polarizing film and the optically anisotropic film or the optically anisotropic layer, the same adhesive layer as that exemplified as the other layer for bonding the horizontally aligned liquid crystal cured film and the vertically aligned liquid crystal cured film can be used.

[0144] The polarizing plate of the present invention may have a structure similar to that of a conventional polarizing plate, or a polarizing film and a retardation film. Examples of such structures include an adhesive layer (sheet) for attaching the polarizing plate to a display element such as a liquid crystal display device, and a protective film used for protecting the surface of a polarizing film or a liquid crystal cured film from scratches and dirt.

[0145] The laminate and polarizing plate of the present invention can be used in various display devices. A display device is a device having a display element, and includes a light-emitting element or a light-emitting device as a light source. Examples of the display device include a liquid crystal display device, an organic electroluminescence (EL) display device, an inorganic electroluminescence (EL) display device, a touch panel display device, an electron emission display device (e.g., a field emission display device (FED) and a surface field emission display device (SED)), electronic paper (a display device using electronic ink or an electrophoretic element, a plasma display device, a projection type display device (e.g., a grating light valve (GLV) display device, a display device having a digital micromirror device (DMD)), and a piezoelectric ceramic display. The liquid crystal display device includes any of a transmissive liquid crystal display device, a semi-transmissive liquid crystal display device, a reflective liquid crystal display device, a direct-view liquid crystal display device, and a projection type liquid crystal display device. In particular, the laminate and the polarizing plate of the present invention can be suitably used in a liquid crystal display device because the effects thereof are easily exhibited, and it is particularly preferable to use them for an IPS (in-plane switching) liquid crystal display device. By using the laminate or the polarizing plate of the present invention, it is possible to easily realize a thin display device and obtain a display device that can exhibit the characteristics of preventing light leakage and color shift when the liquid crystal display device is viewed from an oblique direction during black display. EXAMPLES

[0146] The present invention will be described in more detail below with reference to examples. In the examples, "%" and "parts" mean mass% and mass parts, respectively, unless otherwise specified. The apparatus and measuring methods used in the following examples are as follows. The corona treatment was performed once using AGF-B10 manufactured by Kasuga Electric Co., Ltd., at an output of 0.3 kW and a treatment speed of 3 m / min. The high pressure mercury lamp used was the Uniqure VB-15201BY-A manufactured by Ushio Electric Co., Ltd. The retardation value Rth(λ) in the thickness direction and the film thickness were measured using an ellipsometer M-220 manufactured by JASCO Corporation.

[0147] [Preparation of composition for forming optically anisotropic film] To 100 parts of the polymerizable liquid crystal compound A described below, 0.2 parts of a leveling agent (BYK361N; manufactured by BASF Japan Ltd.), 6 parts of a polymerization initiator 2-dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one (Irgacure 369 (Irg369); manufactured by BASF Japan Ltd.), and 8 parts of dipentaerythritol hexaacrylate (DPHA; manufactured by Tokyo Chemical Industry Co., Ltd.) were added. Further, cyclopentanone was added as a solvent so that the solid content concentration became 12%, and the mixture was stirred at 50° C. for 1 hour to obtain a composition 1 for forming an optically anisotropic film.

[0148] Polymerizable liquid crystal compound A was produced according to the method described in JP-A-2009-173893. The molecular structure is shown below.

[0149] Polymerizable liquid crystal compound A:

[0150] [ka]

[0151] Example 1 The surface of a cycloolefin polymer (COP) film (ZF-14, manufactured by Zeon Corporation) with a thickness of 40 μm was subjected to a corona treatment, and then the composition for forming an optically anisotropic film 1 was applied thereto and dried at 90° C. for 1 minute. After that, ultraviolet light was irradiated from the applied surface using a UniCure (VB-15201BY-A, manufactured by Ushio Inc.) (accumulated light amount at a wavelength of 365 nm in a nitrogen atmosphere: 500 mJ / cm ). 2 ) to form a vertically aligned liquid crystal cured film 1, thereby obtaining a laminate 1. The film thickness of the obtained optically anisotropic film was measured by an ellipsometer and was found to be 1.0 μm. The laminate 1 was placed in an ultraviolet-visible spectrophotometer (Shimadzu Corporation, "UV-2450"), and the absorbance (A1) measured from a certain angle relative to the in-plane direction and the absorbance (A2) measured after rotating the sample 90 degrees in the in-plane direction from the angle at which A1 was measured were measured. The maximum absorbance ratio A1 / A2 in the range of 300 nm to 400 nm was 1.00, and the minimum was 0.97.

[0152] <Evaluation of orientation> The obtained laminate 1 was observed under a magnification of 200 times using a polarizing microscope (Olympus Corporation, "BX-51") The vertical alignment was confirmed and no alignment defects were observed, and the vertical alignment was confirmed and alignment defects were observed, and the vertical alignment was not confirmed and the laminate was evaluated as ×.

[0153] <Analysis of constituent elements> Of the laminates consisting of the optically anisotropic film and substrate prepared by the above-mentioned method, etching was performed from the interface of the optically anisotropic film opposite the substrate using an Ar gas cluster ion beam under the etching conditions shown in Table 1 below, while confirming elemental information using XPS (K-Alpha+ manufactured by Thermo Fisher Scientific). After confirming the etching time required to reach the interface on the substrate side from the interface on the opposite side to the substrate, elemental analysis information was extracted at a point 10 nm from the interface on the opposite side to the substrate to confirm the constituent elements in the liquid crystal cured film at a point 10 nm in the thickness direction from the interface of the optically anisotropic film opposite the substrate to the liquid crystal cured film side. Similarly, the element ratios in the center of the liquid crystal cured film layer were also confirmed, and the oxygen atomic ratio (O) at a point 10 nm from the interface on the opposite side to the substrate was confirmed. S ) and the oxygen atom ratio (O C ) ratio (O S / O C ) are shown in Table 5.

[0154] [Table 1]

[0155] <Preparation of double-sided glass laminate> The laminate 1 obtained above was cut into a size of 10 cm x 10 cm, the substrate side was subjected to a corona treatment, and the laminate was attached to glass via a 25 µm pressure-sensitive adhesive manufactured by Lintec Corporation. Next, the liquid crystal effect film side was also corona-treated and then bonded to a saponified triacetyl cellulose film (Konica Minolta, Inc., KC4UYTAC, thickness 40 μm) via a 25 μm pressure-sensitive adhesive manufactured by Lintec Corporation. The triacetyl cellulose film side was then bonded to glass via a 25 μm pressure-sensitive adhesive manufactured by Lintec Corporation, to obtain a double-sided glass laminate consisting of glass, adhesive, substrate (ZEONOR film), optically anisotropic film, adhesive, triacetyl cellulose film, adhesive, and glass.

[0156] <Initial phase difference measurement> The retardation value in the thickness direction of the double-sided glass laminate was measured as follows. The front retardation value and the retardation value when tilted 40 degrees from the fast axis were measured by changing the incident angle of light on the sample for measuring optical properties (double-sided glass laminate) using KOBRA-WPR manufactured by Oji Scientific Instruments. The average refractive index at each wavelength was measured using an Ellipsometer M-220 manufactured by JASCO Corporation. The film thickness was measured using an Optical NanoGauge film thickness meter C12562-01 manufactured by Hamamatsu Photonics K.K. The three-dimensional refractive index was calculated from the above-mentioned front retardation value, the retardation value when tilted 50 degrees from the fast axis center, the average refractive index, and the film thickness, with reference to Oji Scientific Instruments technical documents (http: / / www.oji-keisoku.co.jp / prod ucts / kobra / reference.html). The optical properties of each optically anisotropic film were calculated from the obtained three-dimensional refractive index according to the following formula. The results are shown in Table 6. RthC(λ)=((nxC(λ)+nyC(λ)) / 2-nzC(λ))×dC RthC(λ) represents the retardation value in the thickness direction of the optically anisotropic film at a wavelength of λ nm. Also, nxC(λ) is the in-plane principal refractive index of the optically anisotropic film at a wavelength of λ nm, nyC(λ) is the refractive index in the direction perpendicular to nxC(λ) at a wavelength of λ nm, nzC(λ) is the refractive index in the thickness direction of the optically anisotropic film at a wavelength of λ nm. When nxC(λ)=nyC(λ), nxC(λ) can be the refractive index in any direction in the film plane, and dC represents the thickness of the optically anisotropic film. (In the formula, Rth(450) represents the out-of-plane retardation value for light with a wavelength of 450 nm, Rth(550) represents the out-of-plane retardation value for light with a wavelength of 550 nm, and Rth(630) represents the out-of-plane retardation value for light with a wavelength of 630 nm.)

[0157] <Measurement of phase difference value after durability test> The double-sided glass laminate was left in a thermostatic chamber set at 105°C for 250 hours, and then removed from the thermostatic chamber and left in a room temperature (25°C 55%) environment for 1 hour, after which the retardation value was measured by the method described above. The retardation value change from the initial value of 20 nm or less was evaluated as ◯, and the retardation value change from the initial value of more than 20 nm was evaluated as ×. The results are shown in Table 5.

[0158] [Production of polarizing film] A polyvinyl alcohol film having an average degree of polymerization of about 2,400, a degree of saponification of 99.9 mol% or more, and a thickness of 75 μm was immersed in pure water at 30° C., and then immersed in an aqueous solution having a weight ratio of iodine / potassium iodide / water of 0.02 / 2 / 100 at 30° C. to perform iodine dyeing (iodine dyeing step). The polyvinyl alcohol film that had undergone the iodine dyeing step was immersed in an aqueous solution having a weight ratio of potassium iodide / boric acid / water of 12 / 5 / 100 at 56.5° C. to perform boric acid treatment (boric acid treatment step). The polyvinyl alcohol film that had undergone the boric acid treatment step was washed with pure water at 8° C., and then dried at 65° C. to obtain a polarizer (thickness 27 μm after stretching) in which iodine was adsorbed and aligned in the polyvinyl alcohol. At this time, stretching was performed in the iodine dyeing step and the boric acid treatment step. The total stretching ratio in such stretching was 5.3 times. The obtained polarizer and a saponified triacetyl cellulose film (KC4UYTAC 40μm, manufactured by Konica Minolta) were bonded together by nip rolls via a water-based adhesive. The resulting laminate was dried at 60°C for 2 minutes while maintaining a tension of 430N / m to obtain a polarizing film having a triacetyl cellulose film as a protective film on one side. The water-based adhesive was prepared by adding 3 parts of carboxyl-modified polyvinyl alcohol (Kuraray Poval KL318, manufactured by Kuraray) and 1.5 parts of water-soluble polyamide epoxy resin (Sumirez Resin 650, manufactured by Sumika Chemtex, aqueous solution with a solid content of 30%) to 100 parts of water.

[0159] The optical properties of the obtained polarizing film were measured. The measurements were performed using a spectrophotometer (V7100, manufactured by JASCO Corporation) with the polarizer surface of the polarizing film obtained above as the incident surface. The resulting luminous efficiency-corrected single transmittance was 42.1%, the luminous efficiency-corrected polarization degree was 99.996%, the single hue a was -1.1, and the single hue b was 3.7.

[0160] After carrying out corona treatment on the optically anisotropic film surface of the laminate 1 obtained above, it was attached to the polarizer side of the polarizing film produced by the above-mentioned method via an adhesive (5 μm pressure-sensitive adhesive manufactured by Lintec Corporation). Next, a cycloolefin polymer film (substrate) (ZEONOR Film, manufactured by Zeon Corporation) with a thickness of 40 μm and a front retardation value of 120 nm, the surface of which was corona-treated, was attached to the ZF-14 side of the polarizing plate laminate 1 via an adhesive (5 μm pressure-sensitive adhesive manufactured by Lintec Corporation), forming a polarizing plate 1 of protective film / water-based adhesive / polarizer / adhesive / optically anisotropic film / substrate (ZF-14) / adhesive / cycloolefin polymer film (front retardation value 120 nm).

[0161] <Checking the oblique hue> The obtained polarizing plate 1 was attached to a backlight via an adhesive, and then visually observed from a distance of 50 cm from an elevation angle of 60° and an azimuth angle of 0 to 360° to confirm the oblique hue. Clear black was rated as ◯, black with some light leakage was △, and light leakage was x.

[0162] (Examples 2 to 4) Optically anisotropic film-forming compositions 2 to 4 were obtained in the same manner as in Example 1, except that the polymerizable liquid crystal compound A was a mixture of the polymerizable liquid crystal compound A and the following polymerizable liquid crystal compounds B and C. The mixing ratios of the polymerizable liquid crystal compounds A, B and C are as shown in Table 2. The ratios of the polymerizable liquid crystal compounds A, B, and C are expressed as parts per 100 parts of the total amount of the polymerizable liquid crystal compounds. Moreover, optically anisotropic films 2 to 4 were formed in the same manner as in Example 1 to obtain laminates 2 to 4. Furthermore, polarizing plates 2 to 4 were obtained in the same manner as in Example 1, except that the obtained laminates 2 to 4 were used. Moreover, evaluations were performed in the same manner as in Example 1. The results are shown in Table 6.

[0163] [Table 2]

[0164] The polymerizable liquid crystal compound B was prepared by the method described in Lub et al., Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996). The molecular structures of each are shown below.

[0165] Polymerizable liquid crystal compound B:

[0166] [ka]

[0167] Polymerizable liquid crystal compound C:

[0168] [ka]

[0169] (Examples 5 to 8) Optically anisotropic film-forming compositions 5 to 8 were obtained in the same manner as in Example 1, except that the amount of dipentaerythritol hexaacrylate (DPHA; manufactured by Tokyo Chemical Industry Co., Ltd.) added was changed as shown in Table 3. Except for using the optically anisotropic film-forming compositions 5 to 8, the optically anisotropic films 5 to 8 were formed in the same manner as in Example 1 to obtain laminates 5 to 8. The obtained laminates were then used to obtain polarizing plates 5 to 8. Evaluations were also performed in the same manner as in Example 1. The results are shown in Table 6.

[0170] [Table 3]

[0171] Example 9 Except for changing the substrate to a cycloolefin polymer film (substrate) (ZEONORFILM, manufactured by Zeon Corporation) having a thickness of 40 μm and a front retardation value of 120 nm, an optically anisotropic film 1 was formed in the same manner as in Example 1 to obtain a laminate 9. After performing a corona treatment on the optically anisotropic film surface of the obtained laminate 9, the polarizer side was attached to the polarizing film manufactured by the above-mentioned method via an adhesive (5 μm pressure-sensitive adhesive manufactured by Lintec Corporation) to form a polarizing plate 9. Evaluation was also performed in the same manner as in Example 1. The results are shown in Table 6.

[0172] Comparative Example 1 [Preparation of alignment film composition for forming optically anisotropic film] A silane coupling agent KBM-9103 manufactured by Shin-Etsu Chemical Co., Ltd. was dissolved in a mixed solvent of ethanol and water in a ratio of 9:1 (weight ratio) to obtain a composition for forming an alignment film with a solid content of 1%. [Preparation of composition for forming optically anisotropic film (composition 9)] An optically anisotropic film-forming composition 9 was obtained in the same manner as in Example 2, except that dipentaerythritol hexaacrylate (DPHA; manufactured by Tokyo Chemical Industry Co., Ltd.) was not added.

[0173] After the surface of a 40 μm thick cycloolefin polymer (COP) film ZF-14 (base material) manufactured by Zeon Corporation was corona-treated, an alignment film composition for forming an optically anisotropic film was applied with a bar coater and dried at 120° C. for 1 minute to obtain an alignment film for forming an optically anisotropic film. The thickness of the obtained alignment film for forming an optically anisotropic film was measured with an ellipsometer to be 100 nm. Next, the composition 9 for forming an optically anisotropic film is applied to the alignment film for forming an optically anisotropic film using a bar coater, dried at 90°C for 1 minute, and then irradiated with ultraviolet light from the coated surface using a UniCure (integrated light amount at a wavelength of 365 nm in a nitrogen atmosphere: 500 mJ / cm 2 ) to form an optically anisotropic film 9, thereby obtaining a laminate 10. Further, a polarizing plate 10 was obtained in the same manner as in Example 1, except that the obtained laminate 10 was used. Moreover, evaluation was performed in the same manner as in Example 1. The results are shown in Table 5.

[0174] Comparative Example 2 [Preparation of optically anisotropic film-forming composition (composition 10)] An optically anisotropic film-forming composition 10 was obtained in the same manner as in Example 1, except that 2 parts of the following ionic compound 1 described in JP 2019-139168 A was added instead of dipentaerythritol hexaacrylate (DPHA; manufactured by Tokyo Chemical Industry Co., Ltd.).

[0175] Ionic compound 1:

[0176] [ka]

[0177] Except for changing the optically anisotropic film-forming composition 1 to 10, the same procedure as in Example 1 was carried out to form an optically anisotropic film 10, and a laminate 11 was obtained. Furthermore, except for using the obtained laminate 11, a polarizing plate 11 was obtained in the same manner as in Example 1. Evaluation was also carried out in the same manner as in Example 1. The results are shown in Table 6.

[0178] (Comparative Examples 3 and 4) Optically anisotropic film-forming compositions 11 and 12 were obtained in the same manner as in Example 1, except that the amount of dipentaerythritol hexaacrylate (DPHA; manufactured by Tokyo Chemical Industry Co., Ltd.) added was changed as shown in Table 4. Optically anisotropic films 11 and 12 were formed in the same manner as in Example 2, except that optically anisotropic film-forming compositions 11 and 12 were used, and laminates 12 and 13 were obtained. Furthermore, polarizing plates 12 and 13 were obtained in the same manner as in Example 1, except that the obtained laminates 12 and 13 were used. Furthermore, evaluations were performed in the same manner as in Example 1. The results are shown in Table 6.

[0179] [Table 4]

[0180] Comparative Example 5 An optically anisotropic film-forming composition 13 was obtained in the same manner as in Example 1, except that the polymerizable liquid crystal compound was changed to a polymerizable liquid crystal compound D described below. Further, an optically anisotropic layer 13 was formed in the same manner as in Example 1 to obtain a laminate 14. Further, a polarizing plate 14 was obtained in the same manner as in Example 1, except that the obtained laminate 14 was used. Further, evaluation was performed in the same manner as in Example 1. The results are shown in Table 6.

[0181] Polymerizable liquid crystal compound D was produced according to the method described in JP-A-2009-173893. The molecular structure is shown below.

[0182] Polymerizable liquid crystal compound D:

[0183] [ka]

[0184] (Comparative Examples 6 to 8) Optically anisotropic film-forming compositions 14 to 16 were obtained in the same manner as in Example 1, except that the polymerizable liquid crystal compound was a mixture of the following polymerizable liquid crystal compounds B, C, and D. The mixing ratios of the polymerizable liquid crystal compounds B, C, and D are as shown in Table 5. The ratios of the polymerizable liquid crystal compounds B, C and D are expressed as parts per 100 parts of the total amount of the polymerizable liquid crystal compounds. Moreover, optically anisotropic films 14 to 16 were formed in the same manner as in Example 1 to obtain laminates 15 to 17. Furthermore, polarizing plates 15 to 17 were obtained in the same manner as in Example 1, except that the obtained laminates 15 to 17 were used. Moreover, evaluations were performed in the same manner as in Example 1. The results are shown in Table 6.

[0185] [Table 5]

[0186] [Table 6]

[0187] According to the present invention, it is possible to provide an optically anisotropic film and laminate that exhibit small thermal retardation change, a polarizing plate including the laminate, and an image display device having these. [Explanation of symbols]

[0188] 1: Optically anisotropic film 2: Optically anisotropic layer 3: Polarizing film 10: Laminate 20: Polarizing plate

Claims

1. A polymerizable liquid crystal composition containing at least one polymerizable liquid crystal compound, the polymerizable liquid crystal composition having a ClogP value of 7 or more, and a reactive group-containing non-liquid crystal compound having at least one reactive group selected from an acryloyloxy group and a methacryloyloxy group in an amount of 3 to 18 parts by mass relative to 100 parts by mass of the total polymerizable liquid crystal compounds.

2. The polymerizable liquid crystal composition according to claim 1 , wherein the weight average molecular weight of the reactive group-containing non-liquid crystal compound is 1,200 or less.

3. The polymerizable liquid crystal composition according to claim 1 , further comprising a smectic liquid crystal compound.

4. The polymerizable liquid crystal composition according to claim 1 , further comprising a polymerizable liquid crystal compound having a polar group.

5. The polymerizable liquid crystal composition according to claim 1 , further comprising a solvent.

6. The polymerizable liquid crystal composition according to claim 1 , further comprising a polymerization initiator.

7. The polymerizable liquid crystal composition according to claim 1 , further comprising a leveling agent.

8. 2. An optically anisotropic film obtained by curing the composition of claim 1, which satisfies the following formula (1): ABOUT Ｓ / ABOUT Ｃ ≧1.1 (1) [In formula (1), O Ｓ is the oxygen atomic ratio at a point 10 nm from the film surface of the optically anisotropic film, and O Ｃ represents the oxygen atomic ratio in the central portion of the optically anisotropic film.

9. The optically anisotropic film according to claim 8 , which satisfies the following formula (2): nx ≈ ny < nz (2) [In formula (2), nx represents the principal refractive index in a direction parallel to the film plane in the index ellipsoid formed by the retardation layer. ny represents the refractive index in a direction parallel to the film plane and perpendicular to the direction of nx in the index ellipsoid formed by the retardation layer. nz represents the refractive index in a direction perpendicular to the film plane in the index ellipsoid formed by the retardation layer.)]

10. 9. The optically anisotropic film according to claim 8, which has a thickness of 0.1 μm or more and 3 μm or less.

11. The optically anisotropic film according to claim 8 , which satisfies the following formula (3): -180nm≦RthC(550)≦-30nm (3) [In formula (3), RthC(550) represents a retardation value in the thickness direction at a wavelength of 550 nm.]

12. The optically anisotropic film according to claim 8 , which satisfies the following formula (4): RthC(450) / RthC(550)≧1.04 (4) [In formula (4), RthC(450) represents a retardation value in the thickness direction at a wavelength of 450 nm, and RthC(550) represents a retardation value in the thickness direction at a wavelength of 550 nm.]

13. A laminate comprising the optically anisotropic film according to claim 8 and an optically anisotropic layer.

14. A polarizing plate comprising a polarizing film and the optically anisotropic film according to claim 8.

15. An image display device comprising the polarizing plate according to claim 14.

Images