JP2018124528A - Composition for optical alignment film, optical alignment film, optical laminate, and image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition for an optical alignment film from which an optical film excellent in alignability can be manufactured, an optical alignment film manufactured by using the same, an optical laminate, and an image display device.SOLUTION: A composition for an optical alignment film contains a polymer A that has a constitutional unit a1 including a cinnamate group, and a low-molecular weight compound B that has a smaller molecular weight than that of the polymer A.SELECTED DRAWING: None

Description

  The present invention relates to a composition for a photoalignment film, a photoalignment film, an optical laminate, and an image display device.

Optical films such as optical compensation sheets and retardation films are used in various image display devices in order to eliminate image coloring and expand the viewing angle.
A stretched birefringent film has been used as the optical film, but recently, it has been proposed to use an optically anisotropic layer made of a liquid crystalline compound instead of the stretched birefringent film.

  It is known that such an optically anisotropic layer is provided with an alignment film on a support on which the optically anisotropic layer is formed in order to align the liquid crystalline compound. A photo-alignment film subjected to a photo-alignment process instead of the process is known.

  For example, Patent Document 1 discloses that “(A) component thermosetting film having photo-alignment property and containing an acrylic copolymer having a photodimerization site and a thermal crosslinking site and (B) a crosslinking agent”. Forming composition ”([Claim 1]), and also describes an embodiment in which the photodimerization site of the component (A) is a cinnamoyl group ([Claim 3]).

Japanese Patent No. 5457520

  The present inventors examined the conventional composition for photo-alignment films described in Patent Document 1 and the like, and found that the material for the support (for example, polymer film, polarizer, etc.) that forms the composition for photo-alignment films It has been clarified that there is a problem that the orientation of the formed photo-alignment film becomes insufficient depending on the conditions of the photo-alignment treatment caused by the above.

  Therefore, the present invention provides a composition for a photo-alignment film that can produce a photo-alignment film having excellent orientation, and a photo-alignment film, an optical laminate, and an image display device that are produced using the composition. Is an issue.

As a result of intensive studies to achieve the above-mentioned problems, the inventors of the present invention are formed by using a composition containing a polymer having a structural unit containing a cinnamate group and a low molecular compound having a cinnamate group. The inventors have found that the alignment property of the photo-alignment film is good and completed the present invention.
That is, it has been found that the above-described problem can be achieved by the following configuration.

[1] a polymer A having a structural unit a1 containing a cinnamate group;
A composition for a photoalignment film, comprising a low molecular compound B having a cinnamate group and having a molecular weight smaller than that of the polymer A.
[2] The composition for a photoalignment film according to [1], wherein the molecular weight of the low molecular compound B is 200 to 500.
[3] The composition for a photoalignment film according to [1] or [2], wherein the content of the low molecular compound B is 10 to 500% by mass with respect to the mass of the structural unit a1 of the polymer A.
[4] The composition for a photoalignment film according to any one of [1] to [3], wherein the low molecular compound B is a compound represented by the following formula (B1).

Here, in formula (B1), a represents an integer of 0 to 5, R ¹ represents a hydrogen atom or a monovalent organic group, and R ² represents a monovalent organic group. When a is 2 or more, the plurality of R ¹ may be the same or different from each other.
[5] The composition for photoalignment film according to any one of [1] to [4], wherein the polymer A further includes a structural unit a2 containing a crosslinkable group.
[6] The composition for a photoalignment film according to any one of [1] to [5], further comprising a crosslinking agent C having a crosslinkable group.

[7] The photoalignment film composition according to any one of [1] to [6] is produced, and the cinnamate groups of the polymer A and the low molecular compound B contained in the photoalignment composition are dimerized. Photoalignment film having a structure in which the cyclobutane ring and / or cinnamate group is isomerized.
[8] An optical laminate having the photo-alignment film according to [7] and an optically anisotropic layer provided on the photo-alignment film and containing a liquid crystalline compound.
[9] The optical laminate according to [8], which includes a support, a photo-alignment film, and an optically anisotropic layer in this order.
[10] An image display device comprising the optical laminate according to any one of [8] and [9].

  According to the present invention, a photoalignment film composition capable of producing a photoalignment film having excellent orientation, and a photoalignment film, an optical laminate and an image display device produced using the composition are provided. Can do.

1A to 1D are schematic cross-sectional views each showing an example of the optical layered body of the present invention.

Hereinafter, the present invention will be described in detail.
The description of the constituent elements described below may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments.
In the present specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

[Composition for photo-alignment film]
The composition for a photoalignment film of the present invention comprises a polymer A having a structural unit a1 containing a cinnamate group, and a low molecular compound B having a cinnamate group and having a molecular weight smaller than that of the polymer A. It is a composition for alignment films.
Here, in this specification, the cinnamate group is a group having a cinnamic acid structure containing cinnamic acid or a derivative thereof as a basic skeleton, and a group represented by the following formula (I) or the following formula (II): Say.

(Wherein, a represents an integer of 0 to 5, R ¹ represents a hydrogen atom or a monovalent organic group, R ² represents a monovalent organic group. When a is 2 or more, a plurality of R ¹ May be the same or different. * Indicates a bond.)
Examples of the monovalent organic group represented by R ¹ include a chain or cyclic alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and an optionally substituted 6 to 6 carbon atoms. And 20 aryl groups.

Since the composition for photo-alignment films of the present invention contains both the polymer A and the low-molecular compound B as described above, the orientation of the produced photo-alignment film becomes good. Although this is not clear in detail, the present inventors presume as follows.
In the case where the temperature condition of the photo-alignment treatment is relaxed by the material of the support for forming the composition for photo-alignment film, the alignment does not proceed sufficiently when a composition not containing the low molecular compound B is used. This is thought to be because the mobility of the cinnamate group is limited by the main chain of the polymer A. In the present invention, by blending the low molecular weight compound B whose thermal motion is not limited by the polymer chain, the orientation of the low molecular weight compound B of the photo-alignment film containing the polymer A becomes an auxiliary or starting point. Thus, it is considered that the orientation of the cinnamate group of the polymer A could also be improved.

  Hereinafter, the polymer A, the low-molecular compound B, and optional components contained in the composition for photo-alignment films of the present invention will be described in detail.

[Polymer A]
The polymer A contained in the composition for photo-alignment film of the present invention is not particularly limited as long as it is a polymer having a structural unit a1 containing a cinnamate group, and a conventionally known polymer can be used.
The main skeleton of the polymer A is, for example, polyamic acid, polyamic acid ester, polyimide, polyorganosiloxane, (meth) acrylic polymer, cycloolefin polymer, polyester, polyamide, polyacetal derivative, polystyrene derivative, poly (styrene- And a skeleton formed by a phenylmaleimide) derivative or the like. In particular, when the alignment layer is provided on the resin film, it is preferable to use at least one selected from the group consisting of a (meth) acrylic polymer and a polyorganosiloxane from the viewpoint of excellent solvent solubility and film handleability.

The preferred molecular weight range of the polymer A is preferably 1,000 to 500,000 in terms of weight average molecular weight from the viewpoints of solvent solubility at the time of coating, viscosity of the solution, and expression and maintenance of the orientation regulating force after the orientation treatment. More preferably, it is -300,000, and it is still more preferable that it is 3000-200000.
Here, the weight average molecular weight is defined as a polystyrene (PS) equivalent value by gel permeation chromatography (GPC) measurement, and the measurement by GPC in the present invention uses HLC-8220 GPC (manufactured by Tosoh Corporation) as a column. It can be measured using TSKgel Super HZM-H, HZ4000, HZ2000.

<Structural unit a1 containing cinnamate group>
As the structural unit a1 containing the cinnamate group of the polymer A, for example, when a (meth) acrylic polymer and a polyorganosiloxane are taken as examples, repeating units represented by the following formulas (A1) and (A2) are used. It can be used suitably.

Here, in the formula (A1), R ¹ represents a hydrogen atom or a methyl group. In the formula (A2), R ² represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an oxygen atom. It represents bonding with other silicon atoms via.
In formula (A1) and formula (A2), L represents a single bond or a divalent linking group, and Y represents a cinnamate group represented by the above formula (I) or (II).
Specific examples of the alkyl group having 1 to 6 carbon atoms of R ² include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and an n-butyl group. An ethyl group is preferred. Specific examples of the alkoxy group having 1 to 6 carbon atoms of R ² include a methoxy group, an ethoxy group, an n-propyloxy group, an isopropyloxy group, and an n-butoxy group. An ethoxy group is preferred.

Specific examples of structures that can be used as L include —O—CO—, —O—CO— (CH ₂ ) _n —O—, —CO—O—Ph—, and —CO—O—Ph—Ph. _{-, - CO-O- (CH} 2) n -, - (CH 2) n -Cy- , and the like. Here, Ph represents a divalent benzene ring (for example, phenylene group) which may have a substituent, and Cy represents a divalent cyclohexane ring (for example, cyclohexane-) which may have a substituent. 1,4-diyl group, etc.). Here, m and n represent an integer of 1 to 4.

More specifically, examples of the structural unit represented by the above formula (A1) include the following structural units.

On the other hand, specific examples of the structural unit represented by the above formula (A2) include the following structural units.

Other examples of Y in the above formulas (A1) and (A2) (cinnamate groups represented by the above formulas (I) and (II)) are described in paragraph [0016] of JP-A-2015-026050. Further, those substituted with the following structures are mentioned. In the following structures, * indicates a bonding position with the main chain structure of the polymer.

<Structural Unit a2 Containing Crosslinkable Group>
In the present invention, it is preferable that the polymer A further has a structural unit a2 containing a crosslinkable group because the orientation is further improved.
The crosslinkable group is preferably a heat crosslinkable group that causes a curing reaction by the action of heat.
The structural unit a2 having a crosslinkable group is represented by, for example, an epoxy group, an oxetanyl group, or —NH—CH ₂ —O—R (R represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms). And a structural unit containing at least one selected from the group consisting of an ethylenically unsaturated group and a blocked isocyanate group.
Among these, a structural unit having an epoxy group and / or an oxetanyl group is preferable. A 3-membered cyclic ether group is also called an epoxy group, and a 4-membered cyclic ether group is also called an oxetanyl group.

  Specific examples of the radical polymerizable monomer used to form the structural unit having an epoxy group include, for example, glycidyl acrylate, glycidyl methacrylate, glycidyl α-ethyl acrylate, and glycidyl α-n-propyl acrylate. Glycidyl α-n-butyl acrylate, 3,4-epoxybutyl acrylate, 3,4-epoxybutyl methacrylate, 3,4-epoxycyclohexylmethyl acrylate, 3,4-epoxycyclohexyl methacrylate Methyl, α-ethylacrylic acid-3,4-epoxycyclohexylmethyl, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, described in paragraphs 0031 to 0035 of Japanese Patent No. 4168443 Alicyclic epoch Such compounds may be mentioned containing shea skeleton, the contents of which are incorporated herein.

Specific examples of the radical polymerizable monomer used for forming the structural unit having an oxetanyl group include, for example, a (meth) acryl having an oxetanyl group described in paragraphs 0011 to 0016 of JP-A No. 2001-330953. Acid esters, and the like, the contents of which are incorporated herein.
Specific examples of the radical polymerizable monomer used for forming the structural unit a2-1 having the epoxy group and / or oxetanyl group include a monomer having a methacrylic ester structure and an acrylic ester structure. A monomer is preferred.

  Among these, preferred are glycidyl methacrylate, 3,4-epoxycyclohexylmethyl acrylate, 3,4-epoxycyclohexylmethyl methacrylate, (3-ethyloxetane-3-yl) methyl acrylate, and methacrylic acid ( 3-ethyloxetane-3-yl) methyl. These structural units can be used individually by 1 type or in combination of 2 or more types.

Preferable specific examples of the structural unit having an epoxy group and / or oxetanyl group include the following structural units. Incidentally, R ¹ and R ² are each the same meaning as R ¹ and R ² in the above-mentioned formula (A1) and formula (A2).

Another example of the structural unit a2 having a crosslinkable group includes a structural unit having an ethylenically unsaturated group. The structural unit having an ethylenically unsaturated group is preferably a structural unit having an ethylenically unsaturated group in the side chain, having an ethylenically unsaturated group at the terminal, and having a side chain having 3 to 16 carbon atoms. Units are more preferred.
About the structural unit which has an ethylenically unsaturated group, description of Paragraphs 0072-0090 of Unexamined-Japanese-Patent No. 2011-215580 and description of Paragraphs 0013-0031 of Unexamined-Japanese-Patent No. 2008-256974 can be referred, These contents Is incorporated herein.

  In the above, compounds that can be used to form a structural unit having a crosslinkable group are exemplified, but it is not always necessary to form such a compound, and for example, an intermediate of the polymer A is pendant with a crosslinkable group. May be formed.

<Other structural units>
In the present invention, the polymer A may have a structural unit other than the structural unit a1 and the structural unit a2 described above. By including other structural units in the copolymer, for example, substrate adhesion, solvent solubility, heat resistance and the like can be improved.
From the viewpoint of substrate adhesion and solvent solubility, a functional group that adjusts the polarity of the polymer A, for example, a structural unit containing a hydroxyl group, a carboxylic acid group, or an ionic group from the viewpoint of imparting hydrophilicity, From the viewpoint of imparting oiliness, structural units having higher alkyl groups and aromatic groups can be imparted respectively. From the viewpoint of achieving both substrate adhesion and solvent solubility, it is preferable to provide a structural unit having a 5-membered or higher heterocyclic ring, cyclic ketone, or aromatic ring. Further, from the viewpoint of improving heat resistance, a structural unit having a rigid structure can be provided.

<Content>
In this invention, when the content of the said polymer A contains the organic solvent mentioned later, it is preferable that it is 0.1-50 mass parts with respect to 100 mass parts of solvent, 0.5-10 mass parts It is more preferable that

[Low molecular compound B]
The low molecular compound B contained in the composition for photo-alignment films of the present invention is a compound having a cinnamate group and having a molecular weight smaller than that of the polymer A.
As described above, the composition for a photo-alignment film of the present invention contains the low molecular compound B, so that the alignment property of the produced photo-alignment film becomes good.

  In the present invention, the molecular weight of the low molecular weight compound B is preferably 200 to 500, more preferably 200 to 400, because the orientation is further improved.

Examples of the low molecular compound B include a compound represented by the following formula (B1).

Here, in formula (B1), a represents an integer of 0 to 5, R ¹ represents a hydrogen atom or a monovalent organic group, and R ² represents a monovalent organic group. When a is 2 or more, the plurality of R ¹ may be the same or different from each other.
Examples of the monovalent organic group represented by R ¹ include, for example, a linear or cyclic alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and an optionally substituted carbon number. Examples thereof include 6 to 20 aryl groups, among which an alkoxy group having 1 to 20 carbon atoms is preferable, an alkoxy group having 1 to 6 carbon atoms is more preferable, and a methoxy group and an ethoxy group are further preferable.
The monovalent organic group R ^2, for example, include a chain or cyclic alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms which may optionally have a substituent Among them, a chain alkyl group having 1 to 20 carbon atoms is preferable, and a branched alkyl group having 1 to 10 carbon atoms is more preferable.
Further, a is preferably ¹ , and R ¹ is preferably in the para position.
Moreover, as a substituent which the aryl group mentioned above may have, an alkoxy group, a hydroxy group, a carboxy group, an amino group etc. are mentioned, for example.

  Specific examples of the compound represented by the formula (B1) include octyl cinnamate, ethyl-4-isopropyl cinnamate, ethyl-2,4-diisopropyl cinnamate, methyl-2,4-diisopropyl cinnamate. Mate, propyl-p-methoxycinnamate, isopropyl-p-methoxycinnamate, isoamyl-p-methoxycinnamate, 2-ethylhexyl-p-methoxycinnamate, 2-ethoxyethyl-p-methoxycinnamate, 2-hexyl Examples include decanyl-p-methoxycinnamate and cyclohexyl-p-methoxycinnamate.

<Content>
In the present invention, the content of the low molecular compound B is 10 to 500% by mass with respect to the mass of the structural unit a1 of the polymer A because the orientation of the produced photoalignment film becomes better. It is preferable that it is 30 to 300% by mass.
The content of the low-molecular compound B is preferably 0.01 to 50 parts by mass, and 0.1 to 10 parts by mass with respect to 100 parts by mass of the solvent when the organic solvent described later is contained. Is more preferable.

[Crosslinking agent C]
The composition for photo-alignment films of the present invention contains a crosslinking agent C having a crosslinkable group separately from the polymer A having the structural unit a2 containing a crosslinkable group, for the reason that the orientation is further improved. It is preferable.
The molecular weight of the crosslinking agent C is preferably 1000 or less, more preferably 100 to 500.

The crosslinkable group is preferably a heat crosslinkable group that causes a curing reaction by the action of heat.
Examples of the crosslinking agent C include compounds having two or more epoxy groups or oxetanyl groups in the molecule, blocked isocyanate compounds (compounds having a protected isocyanato group), and alkoxymethyl group-containing compounds.
Of these, compounds having two or more epoxy groups or oxetanyl groups in the molecule and block isocyanate compounds, which are shown below as specific examples, are preferred.

<Compound having two or more epoxy groups in the molecule>
Specific examples of the compound having two or more epoxy groups in the molecule include aliphatic epoxy compounds.
These are available as commercial products. For example, Denacol EX-611, EX-612, EX-614, EX-614B, EX-622, EX-512, EX-521, EX-411, EX-421, EX-313, EX-314, EX-321 , EX-211, EX-212, EX-810, EX-811, EX-850, EX-851, EX-821, EX-830, EX-832, EX-841, EX-911, EX-941, EX -920, EX-931, EX-212L, EX-214L, EX-216L, EX-321L, EX-850L, DLC-201, DLC-203, DLC-204, DLC-205, DLC-206, DLC-301 , DLC-402 (manufactured by Nagase ChemteX Corporation), Celoxide 2021P, 2081, 3000, EHPE31 0, Epolead GT401, Serubinasu B0134, B0177 ((Ltd.) manufactured by Daicel), and the like.
These can be used alone or in combination of two or more.

<Compounds having two or more oxetanyl groups in the molecule>
As specific examples of the compound having two or more oxetanyl groups in the molecule, Aron oxetane OXT-121, OXT-221, OX-SQ, PNOX (manufactured by Toagosei Co., Ltd.) can be used.

<Block isocyanate compound>
The blocked isocyanate compound is not particularly limited as long as the isocyanate group has a chemically protected blocked isocyanate group, but is a compound having two or more blocked isocyanate groups in one molecule from the viewpoint of curability. It is preferable.
In addition, the blocked isocyanate group in this invention is a group which can produce | generate an isocyanate group with a heat | fever, For example, the group which reacted the blocking agent and the isocyanate group and protected the isocyanate group can illustrate preferably. Moreover, it is preferable that the said blocked isocyanate group is a group which can produce | generate an isocyanate group with the heat | fever of 90 to 250 degreeC.
Further, the skeleton of the blocked isocyanate compound is not particularly limited and may be any as long as it has two isocyanate groups in one molecule, and may be aliphatic, alicyclic or aromatic. Polyisocyanate may be used, for example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, isophorone diisocyanate, 1,6-hexamethylene diisocyanate, 1,3-trimethylene diisocyanate, 1,4-tetramethylene Diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, 1,9-nonamethylene diisocyanate, 1,10-decamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 2, '-Diethyl ether diisocyanate, diphenylmethane-4,4'-diisocyanate, o-xylene diisocyanate, m-xylene diisocyanate, p-xylene diisocyanate, methylene bis (cyclohexyl isocyanate), cyclohexane-1,3-dimethylene diisocyanate, cyclohexane-1, 4-dimethylene diisocyanate, 1,5-naphthalene diisocyanate, p-phenylene diisocyanate, 3,3′-methylene ditolylene-4,4′-diisocyanate, 4,4′-diphenyl ether diisocyanate, tetrachlorophenylene diisocyanate, norbornane diisocyanate, Isocyanate compounds such as hydrogenated 1,3-xylylene diisocyanate and hydrogenated 1,4-xylylene diisocyanate In addition, a prepolymer type skeleton compound derived from these compounds can be preferably used. Among these, tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), hexamethylene diisocyanate (HDI), and isophorone diisocyanate (IPDI) are particularly preferable.

Examples of the matrix structure of the blocked isocyanate compound include biuret type, isocyanurate type, adduct type, and bifunctional prepolymer type.
Examples of the blocking agent that forms the block structure of the blocked isocyanate compound include oxime compounds, lactam compounds, phenol compounds, alcohol compounds, amine compounds, active methylene compounds, pyrazole compounds, mercaptan compounds, imidazole compounds, and imide compounds. be able to. Among these, a blocking agent selected from oxime compounds, lactam compounds, phenol compounds, alcohol compounds, amine compounds, active methylene compounds, and pyrazole compounds is particularly preferable.

  The block isocyanate compound is available as a commercial product. For example, Coronate AP Stable M, Coronate 2503, 2515, 2507, 2513, 2555, Millionate MS-50 (above, manufactured by Nippon Polyurethane Industry Co., Ltd.), Takenate B -830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, B-882N (manufactured by Mitsui Chemicals, Inc.), Duranate 17B-60PX, 17B-60P, TPA-B80X, TPA-B80E, MF-B60X, MF-B60B, MF-K60X, MF-K60B, E402-B80B, SBN-70D, SBB-70P, K6000 (above, manufactured by Asahi Kasei Chemicals Corporation), Death Module BL1100, BL1265 MPA / X, L3575 / 1, BL3272MPA, BL3370MPA, BL3475BA / SN, BL5375MPA, VPLS2078 / 2, BL4265SN, PL340, PL350, Sumidur BL3175 (above, manufactured by Sumika Bayer Urethane Co.) can be preferably used, and the like.

<Content>
In this invention, it is preferable that it is 1-1000 mass parts with respect to 100 mass parts of the structural unit a1 of the polymer A, when containing the said crosslinking agent C, It is 10-500 mass parts. Is preferred.
Moreover, when containing the said crosslinking agent C, when containing the organic solvent mentioned later, it is preferable that it is 0.05-50 mass parts with respect to 100 mass parts of solvent, and is 1-10 mass parts. More preferably.

[Organic solvent]
The composition for a photo-alignment film of the present invention preferably contains an organic solvent from the viewpoint of workability for producing the photo-alignment film.
Specific examples of the organic solvent include ketones (eg, acetone, 2-butanone, methyl isobutyl ketone, cyclohexanone, cyclopentanone, etc.), ethers (eg, dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons. (E.g., hexane), alicyclic hydrocarbons (e.g., cyclohexane), aromatic hydrocarbons (e.g., toluene, xylene, trimethylbenzene), halogenated carbons (e.g., dichloromethane, dichloroethane, di) Chlorobenzene, chlorotoluene, etc.), esters (eg, methyl acetate, ethyl acetate, butyl acetate, etc.), water, alcohols (eg, ethanol, isopropanol, butanol, cyclohexanol, etc.), cellosolves (eg, methyl cellosolve, ethyl) Rosolve, etc.), cellosolve acetates, sulfoxides (eg, dimethyl sulfoxide, etc.), amides (eg, dimethylformamide, dimethylacetamide, etc.), etc., and these may be used alone or in combination of two or more. You may use together.

[Other components D]
The photo-alignment composition of the present invention may contain components other than those described above, and examples thereof include a crosslinking accelerator, an adhesion improver, a leveling agent, and a plasticizer. Examples of the crosslinking accelerator include various metal salt chelate compounds and latent acid generators. As the adhesion improving agent, leveling agent, plasticizer, and the like, various known materials that are conventionally known to be added to the coating composition can be used.

[Photo-alignment film]
The photo-alignment film of the present invention is produced using the above-described composition for photo-alignment film of the present invention, and a cyclobutane ring in which the cinnamate groups of the polymer A and the low-molecular compound B contained in the photo-alignment composition are dimerized. And / or a photo-alignment film having a structure in which the cinnamate group is isomerized.

  There is no restriction | limiting in particular as a film thickness of a photo-alignment film | membrane, Although it can select suitably according to the objective, 10-1000 nm is preferable and 10-300 nm is more preferable.

  Furthermore, in this invention, the material of WO2014-171376 and WO2014-073658 can also be used as a photo-alignment film material.

〔Production method〕
The photo-alignment film of the present invention can be produced by a conventionally known production method except that the above-described composition for a photo-alignment film of the present invention is used. For example, the photo-alignment film of the present invention described above is supported. It can be produced by a production method having a coating step of applying to the body surface and a light irradiation step of irradiating the coating film of the composition for photo-alignment film with polarized light or non-polarized light from an oblique direction with respect to the coating film surface. it can.
In addition, about a support body, it demonstrates in the optical laminated body of this invention mentioned later.

<Application process>
The application method in the application step is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include spin coating, die coating, gravure coating, flexographic printing, and inkjet printing.

<Light irradiation process>
In the light irradiation step, the polarized light applied to the coating film of the composition for photo-alignment film is not particularly limited, and examples thereof include linearly polarized light, circularly polarized light, and elliptically polarized light. Among these, linearly polarized light is preferable.
Further, the “oblique direction” for irradiating non-polarized light is not particularly limited as long as it is a direction inclined by a polar angle θ (0 <θ <90 °) with respect to the normal direction of the coating film surface, and depending on the purpose. The angle θ is preferably 20 to 80 °.

The wavelength in polarized light or non-polarized light is not particularly limited as long as the coating film of the composition for photo-alignment film can impart alignment control ability to liquid crystal molecules, but for example, ultraviolet light, near ultraviolet light, visible light, etc. Is mentioned. Among these, near ultraviolet rays of 250 nm to 450 nm are particularly preferable.
Examples of the light source for irradiating polarized light or non-polarized light include a xenon lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, and a metal halide lamp. By using an interference filter, a color filter, or the like for ultraviolet rays or visible light obtained from such a light source, the wavelength range to be irradiated can be limited. Moreover, linearly polarized light can be obtained by using a polarizing filter or a polarizing prism for the light from these light sources.

The accumulated light quantity of polarized light or non-polarized light is not particularly limited as long as it can impart alignment controllability to liquid crystal molecules to the coating film of the composition for photo-alignment film, but is not particularly limited, but 1 to 300 mJ / cm ² is preferable, and 5 to 100 mJ / cm ² is more preferable.
The illuminance for polarized light or non-polarized light is not particularly limited as long as it can provide the alignment controllability for liquid crystal molecules to the coating film of the composition for photo-alignment film, but is preferably 0.1 to 300 mW / cm ^2. 1 to 100 mW / cm ² is more preferable.

[Optical laminate]
The optical laminate of the present invention is an optical laminate having the above-described photo-alignment film of the present invention and an optically anisotropic layer provided on the photo-alignment film and containing a liquid crystalline compound.
Further, the optical layered body of the present invention preferably further has a support, and specifically, preferably has a support, a photo-alignment film, and an optically anisotropic layer in this order. .

1A to 1D are schematic cross-sectional views each showing an example of the optical layered body of the present invention. 1A to 1D are schematic diagrams, and the relationship between the thicknesses of the layers does not necessarily match the actual one.
An optical laminate 10 shown in FIG. 1A has a photo-alignment film 1 and an optically anisotropic layer 2 in this order.
The optical laminated body 20 shown in FIG. 1 (B) has the support body 3, the photo-alignment film | membrane 1, and the optically anisotropic layer 2 in this order.
The optical laminate 30 shown in FIG. 1C has a polymer film 3b and a polarizer 3a, a photo-alignment film 1, and an optically anisotropic layer 2 in this order.
The optical layered body 40 shown in FIG. 1D includes the support 3, the photo-alignment film 1, the first optical anisotropic layer 2a, and the second optical anisotropic layer 2b in this order.

(Optically anisotropic layer)
The optically anisotropic layer of the optical layered body of the present invention is not particularly limited as long as it is an optically anisotropic layer containing a liquid crystalline compound, and a conventionally known optically anisotropic layer may be appropriately employed and used. it can.
Such an optically anisotropic layer is a layer obtained by curing a composition containing a liquid crystal compound having a polymerizable group (hereinafter also referred to as “optically anisotropic layer forming composition”). Preferably, it may be a single layer structure or a structure (laminate) in which a plurality of layers are laminated.
Hereinafter, the liquid crystal compound and optional additives contained in the composition for forming an optically anisotropic layer will be described.

<Liquid crystal compound>
The liquid crystalline compound contained in the composition for forming an optically anisotropic layer is a liquid crystalline compound having a polymerizable group.
In general, liquid crystal compounds can be classified into a rod-shaped type and a disk-shaped type based on their shapes. In addition, there are low and high molecular types, respectively. Polymer generally refers to a polymer having a degree of polymerization of 100 or more (Polymer Physics / Phase Transition Dynamics, Masao Doi, 2 pages, Iwanami Shoten, 1992).
In the present invention, any liquid crystal compound can be used, but a rod-like liquid crystal compound or a discotic liquid crystal compound is preferably used, and a rod-like liquid crystal compound is more preferably used.

  In the present invention, a liquid crystalline compound having a polymerizable group is used for immobilizing the above-mentioned liquid crystalline compound, but it is more preferable that the liquid crystalline compound has two or more polymerizable groups in one molecule. In addition, when a liquid crystalline compound is a 2 or more types of mixture, it is preferable that at least 1 type of liquid crystalline compound has a 2 or more polymeric group in 1 molecule. In addition, after the liquid crystal compound is fixed by polymerization, it is no longer necessary to exhibit liquid crystallinity.

  Moreover, the kind in particular of polymeric group is not restrict | limited, The functional group in which addition polymerization reaction is possible is preferable, and a polymerizable ethylenically unsaturated group or a ring-polymerizable group is preferable. More specifically, a (meth) acryloyl group, a vinyl group, a styryl group, an allyl group, etc. are mentioned preferably, and a (meth) acryloyl group is more preferable. The (meth) acryloyl group is a notation meaning a methacryloyl group or an acryloyl group.

  As the rod-like liquid crystalline compound, for example, those described in claim 1 of JP-T-11-53019 and paragraphs [0026] to [0098] of JP-A-2005-289980 can be preferably used. As the tick liquid crystal compound, for example, those described in paragraphs [0020] to [0067] of JP-A-2007-108732 and paragraphs [0013] to [0108] of JP-A-2010-244038 are preferably used. However, it is not limited to these.

<Additives>
The composition for forming an optically anisotropic layer may contain components other than the liquid crystalline compounds described above.
For example, the composition for forming an optically anisotropic layer may contain a polymerization initiator. The polymerization initiator used is selected according to the type of the polymerization reaction, and examples thereof include a thermal polymerization initiator and a photopolymerization initiator. For example, examples of photopolymerization initiators include α-carbonyl compounds, acyloin ethers, α-hydrocarbon substituted aromatic acyloin compounds, polynuclear quinone compounds, combinations of triarylimidazole dimers and p-aminophenyl ketones, and oxime esters. And the like.
The amount of the polymerization initiator used is preferably 0.01 to 20% by mass and more preferably 0.5 to 5% by mass with respect to the total solid content of the composition.

The composition for forming an optically anisotropic layer may contain a polymerizable monomer from the viewpoint of the uniformity of the coating film and the strength of the film.
Examples of the polymerizable monomer include radically polymerizable or cationically polymerizable compounds. Preferably, it is a polyfunctional radically polymerizable monomer and is preferably copolymerizable with the polymerizable group-containing liquid crystalline compound. Examples thereof include those described in paragraphs [0018] to [0020] in JP-A No. 2002-296423.
The addition amount of the polymerizable monomer is preferably 1 to 50% by mass and more preferably 2 to 30% by mass with respect to the total mass of the liquid crystal compound.

Further, the composition for forming an optically anisotropic layer may contain a surfactant from the viewpoint of the uniformity of the coating film and the strength of the film.
Examples of the surfactant include conventionally known compounds, and fluorine compounds are particularly preferable. Specifically, for example, compounds described in paragraphs [0028] to [0056] in JP-A No. 2001-330725, and compounds described in paragraphs [0069] to [0126] in Japanese Patent Application No. 2003-295212. Is mentioned.

One of the structural units of the surfactant of the present invention includes a linking group represented by the general formula (3) and having a structural site that is cleaved by light, heat, acid or base stimulation. It is preferable that a linking group having a structural site that is cleaved by light, heat, or acid or base stimulation, and a low-polarity substituent in the same molecule, and a linking group having a structural site that is cleaved by acid stimulation and a fluorine group. More preferably, it is in the same molecule.

  In general formula (3), it is preferable that R2-R5 is a hydrogen atom, ma is 1 or 2, na is 4 or 6, and X is a fluorine atom.

(Example compounds)
The repeating unit represented by the general formula (3) can be obtained by polymerization of monomers. Specific examples of preferable monomers giving the repeating unit represented by the general formula (3) are shown below.

One of the structural units of the polymer of the present invention is a compound represented by the general formula (4).

  In the general formula (4), L is a group consisting of a substituted or unsubstituted aliphatic chain group, a substituted or unsubstituted aliphatic cyclic group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group. A divalent linking group composed of at least one selected from the above, preferably an aliphatic chain group or a cyclic group or a combination thereof, and an aliphatic chain group or a cyclic group having 2 to 8 carbon atoms Most preferably. Y represents a hydrogen atom or an organic group having 1 to 18 carbon atoms, and is most preferably a hydrogen atom, a methoxy group, or a cyclohexyl group. R6 is preferably a hydrogen atom or a methyl group.

Although the specific example of the preferable monomer which gives the repeating unit represented by General formula (4) below is shown, this invention is not limited to this.

Next, although the preferable specific example of the copolymer which has a repeating unit represented by General formula (3) and (4) is shown, this invention is not limited to these.

  Moreover, the polymer in this invention has repeating units (other repeating units) other than the repeating unit represented by General formula (3) and the repeating unit represented by General formula (4) as needed. It may be.

1000-500000 are preferable, as for the weight average molecular weight (Mw) of the polymer of this invention, 1500-400000 are more preferable, and 2000-300000 are especially preferable.
500-250,000 are preferable, as for the number average molecular weight (Mn) of the polymer of this invention, 1000-200000 are more preferable, and 1500-150,000 are especially preferable.
The dispersion degree (Mw / Mn) of the polymer of the present invention is preferably 1.00 to 20.00, more preferably 1.00 to 18.00, and particularly preferably 1.00 to 16.00.
In addition, a weight average molecular weight and a number average molecular weight are the values measured on condition of the following by gel permeation chromatography (GPC).

  The composition for forming an optically anisotropic layer may contain an organic solvent. As an organic solvent, the thing similar to what was demonstrated in the composition for photo-alignment films | membranes of this invention mentioned above can be mentioned.

Further, the composition for forming an optically anisotropic layer includes a vertical alignment accelerator such as a polarizer interface side vertical alignment agent and an air interface side vertical alignment agent, a horizontal direction alignment agent such as a polarizer interface side horizontal alignment agent, and an air interface side horizontal alignment agent. Various alignment agents such as an alignment accelerator may be contained.
Furthermore, in addition to the above components, the composition for forming an optically anisotropic layer may contain an adhesion improving agent, a plasticizer, a polymer, and the like.

The method for forming an optically anisotropic layer using the composition for forming an optically anisotropic layer having such a component is not particularly limited. For example, the optically anisotropic layer is formed on the above-described photo-alignment film of the present invention. It can form by apply | coating the composition for formation, forming a coating film, and performing a hardening process (ultraviolet irradiation (light irradiation process) or heat processing) with respect to the obtained coating film.
The composition for forming an optically anisotropic layer can be applied by a known method (for example, a wire bar coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, or a die coating method).

  In the present invention, the thickness of the optically anisotropic layer is not particularly limited, but is preferably 0.1 to 10 μm, and more preferably 0.5 to 5 μm.

In the present invention, when the optically anisotropic layer is desired to function as a positive A plate, it is preferably an optically anisotropic layer in which rod-like liquid crystalline compounds are homogeneously (horizontal) oriented.
Further, in order to adjust the phase difference change in the oblique incident direction in which the positive A plate is generated, the optically anisotropic layer includes a first optically anisotropic layer in which a rod-like liquid crystal compound is homogeneously (horizontal) oriented, and a rod-like liquid crystal. It is preferable to have a second optically anisotropic layer in which the organic compound is homeotropically (vertically) aligned.

  Furthermore, in the present invention, for the reason that the orientation of the optically anisotropic layer is further improved, the optically anisotropic layer is polymerized after orienting the optically anisotropic layer forming composition described above into a smectic phase ( A layer obtained by fixing the orientation is preferable.

  The optically anisotropic layer of the present invention may have a support, or only the optically anisotropic layer may be peeled off from the support.

The optically anisotropic layer of the optical layered body of the present invention preferably satisfies the following formula (II) from the viewpoint of imparting excellent viewing angle characteristics.
0.75 <(450) / Re (550) <1.00 (II)
Here, in formula (II), Re (450) represents the in-plane retardation of the optically anisotropic layer at a wavelength of 450 nm, and Re (550) represents the in-plane retardation of the optically anisotropic layer at a wavelength of 550 nm. Represents.
Moreover, the value of in-plane retardation means the value measured using the light of a measurement wavelength using AxoScan OPMF-1 (made by Optoscience).

[Support]
As described above, the optical layered body of the present invention may have a support as a base material for forming the optically anisotropic layer.
Examples of such a support include a polarizer and a polymer film, and combinations thereof, for example, a laminate of a polarizer and a polymer film, a laminate of a polymer film, a polarizer and a polymer film. It may be a body. Moreover, the support body may be provided so as to be peelable from the photo-alignment layer and the optically anisotropic layer as necessary.

<Polarizer>
In the present invention, when the optical layered body of the present invention is used for an image display device, a polarizer can be used as a support.
A polarizer will not be specifically limited if it is a member which has the function to convert light into specific linearly polarized light, A conventionally well-known absorption type polarizer and reflection type polarizer can be utilized.
As the absorption polarizer, an iodine polarizer, a dye polarizer using a dichroic dye, a polyene polarizer, and the like are used. Iodine polarizers and dye polarizers include coating polarizers and stretchable polarizers, both of which can be applied. Polarized light produced by adsorbing iodine or dichroic dye to polyvinyl alcohol and stretching. A child is preferred.
Further, as a method for obtaining a polarizer by stretching and dyeing in the state of a laminated film in which a polyvinyl alcohol layer is formed on a substrate, Patent No. 5048120, Patent No. 5143918, Patent No. 5048120, Patent No. 4691205, Japanese Patent No. 4751481, and Japanese Patent No. 4751486 can be cited, and known techniques relating to these polarizers can also be preferably used.
As the reflective polarizer, a polarizer in which thin films having different birefringence are stacked, a wire grid polarizer, a polarizer in which a cholesteric liquid crystal having a selective reflection region and a quarter wavelength plate are combined, or the like is used.
Among these, from the viewpoint of handleability, a polyvinyl alcohol resin (a polymer containing —CH ₂ —CHOH— as a repeating unit, in particular, at least one selected from the group consisting of polyvinyl alcohol and an ethylene-vinyl alcohol copolymer). It is preferable that it is a polarizer containing.

  Although the thickness of a polarizer is not specifically limited, It is preferable that it is 1-60 micrometers, It is more preferable that it is 1-30 micrometers, It is still more preferable that it is 2-20 micrometers.

<Polymer film>
A polymer film is not specifically limited, The polymer film (for example, polarizer protective film etc.) used normally can be used.
Specifically, the polymer constituting the polymer film is, for example, a cellulose-based polymer; an acrylic polymer having an acrylate polymer such as polymethyl methacrylate or a lactone ring-containing polymer; a thermoplastic norbornene-based polymer; a polycarbonate-based polymer. Polymers: Polyester polymers such as polyethylene terephthalate and polyethylene naphthalate; Styrene polymers such as polystyrene and acrylonitrile / styrene copolymer (AS resin); Polyolefin polymers such as polyethylene, polypropylene and ethylene / propylene copolymer; Vinyl polymers; Amide polymers such as nylon and aromatic polyamide; Imide polymers; Sulfone polymers; Polyether sulfone polymers; Polyether ether keto System polymers; polyphenylene sulfide-based polymers; vinylidene chloride polymer; vinyl alcohol-based polymer, vinyl butyral-based polymers; arylate polymers; polyoxymethylene polymers, epoxy-based polymers; or polymers obtained by mixing these polymers.

Among these, a cellulose polymer represented by triacetyl cellulose (hereinafter also referred to as “cellulose acylate”) can be preferably used.
From the viewpoint of processability and optical performance, it is also preferable to use an acrylic polymer.
Examples of the acrylic polymer include polymethyl methacrylate and lactone ring-containing polymers described in paragraphs [0017] to [0107] of JP-A-2009-98605.

  The thickness of the polymer film is not particularly limited, but is preferably 40 μm or less because the thickness of the optical laminate can be reduced. Although a minimum is not specifically limited, Usually, it is 5 micrometers or more.

In this invention, it is preferable that the glass transition temperature of a support body is 130 degrees C or less from the reason for which the predominance using the composition for photo-alignment films | membranes of this invention becomes high. Such a support is likely to be wrinkled or deformed by the heat during the formation of the photo-alignment film or the alignment treatment in the conventional composition for photo-alignment films, but according to the present invention, photo-alignment is not caused without causing such difficulties. A film can be formed.
Here, in this specification, with a differential scanning calorimeter (X-DSC7000 (manufactured by IT Measurement & Control Co., Ltd.)), 20 mg of the sample of the support is put in a measurement pan, and this is speeded in a nitrogen residence. The temperature was raised from 30 ° C. to 120 ° C. at 10 ° C./min and held for 15 minutes, and then cooled to 30 ° C. at −20 ° C./min. Thereafter, the temperature is raised again from 30 ° C. to 250 ° C., and the temperature at which the baseline starts to deviate from the low temperature side is defined as the glass transition temperature Tg.

  In the present invention, the thickness of the support is not particularly limited, but is preferably 1 to 100 μm, and more preferably 5 to 50 μm. In addition, the thickness of the said support body means the total thickness of these thickness, when it has both a polarizer and a polymer film.

[Image display device]
The image display device of the present invention is an image display device having the optical laminate of the present invention.
The display element used in the image display device of the present invention is not particularly limited, and examples thereof include a liquid crystal cell, an organic electroluminescence (hereinafter abbreviated as “EL”) display panel, a plasma display panel, and the like. On the other hand, it can also be used for optical compensation for improving the display image quality, and can also be used for suppressing deterioration of the display image quality due to reflection of external light by the display element.

[Liquid Crystal Display]
The liquid crystal display device which is an example of the image display device of the present invention is a liquid crystal display device having the above-described optical laminate of the present invention and a liquid crystal cell.
In the present invention, among the polarizing plates provided on both sides of the liquid crystal cell, it is preferable to use the optical layered body of the present invention as a polarizing plate on the front side.
Below, the liquid crystal cell which comprises a liquid crystal display device is explained in full detail.

<Liquid crystal cell>
The liquid crystal cell used in the liquid crystal display device is preferably a VA (Virtual Alignment Bend) mode, an OCB (Optical Compensated Bend) mode, an IPS (In-Placed Switching) mode, or a TN (Twisted Nematic). It is not limited to.
In a TN mode liquid crystal cell, rod-like liquid crystal molecules are substantially horizontally aligned when no voltage is applied, and are twisted and aligned at 60 to 120 °. The TN mode liquid crystal cell is most frequently used as a color TFT liquid crystal display device, and is described in many documents.

  In a VA mode liquid crystal cell, rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied. The VA mode liquid crystal cell includes (1) a narrowly defined VA mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied, and substantially horizontally when a voltage is applied (Japanese Patent Laid-Open No. Hei 2-). 176625) (2) Liquid crystal cell (SID97, Digest of tech. Papers (Preliminary Proceed) 28 (1997) 845 in which the VA mode is converted into a multi-domain (MVA mode) for widening the viewing angle. ), (3) A liquid crystal cell in a mode (n-ASM mode) in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied (Preliminary collections 58-59 of the Japan Liquid Crystal Society) (1998)) and (4) SURVIVAL mode liquid crystal cells (announced at LCD International 98). Moreover, any of PVA (Patterned Vertical Alignment) type, optical alignment type (Optical Alignment), and PSA (Polymer-Stained Alignment) may be used. Details of these modes are described in JP-A-2006-215326 and JP-T-2008-538819.

  In an IPS mode liquid crystal cell, rod-like liquid crystal molecules are aligned substantially parallel to the substrate, and the liquid crystal molecules respond in a planar manner when an electric field parallel to the substrate surface is applied. The IPS mode displays black when no electric field is applied, and the absorption axes of the pair of upper and lower polarizing plates are orthogonal. JP-A-10-54982, JP-A-11-202323, and JP-A-9-292522 are methods for reducing leakage light at the time of black display in an oblique direction and improving a viewing angle using an optical compensation sheet. No. 11-133408, No. 11-305217, No. 10-307291, and the like.

[Organic EL display device]
In the organic EL display device, by arranging the optical laminate of the present invention so that the polarizer, the optically anisotropic layer, and the organic EL panel are in this order, external light is reflected on the electrodes of the organic EL panel. The phenomenon of lowering the display contrast can be suppressed and high-quality display can be realized. As the organic EL panel, a known configuration can be widely used, and a touch panel can be further provided.

  Hereinafter, the present invention will be described in more detail based on examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the following examples.

[Synthesis of Polymer A]
<Polymer A1>
A flask equipped with a condenser and a stirrer was charged with 1 part by mass of 2,2′-azobis (isobutyronitrile) as a polymerization initiator and 180 parts by mass of diethylene glycol methyl ethyl ether as a solvent. To this, 100 parts by mass of 3,4-epoxycyclohexylmethyl methacrylate was added, and the inside of the flask was purged with nitrogen, followed by gentle stirring. By raising the solution temperature to 80 ° C. and maintaining this temperature for 5 hours, a polymer solution containing about 35% by weight of polymethacrylate having an epoxy group was obtained. The obtained epoxy-containing polymethacrylate had a weight average molecular weight Mw of 25,000.
Subsequently, in another reaction vessel, 286 parts by mass of the solution containing the epoxy-containing polymethacrylate obtained above (100 parts by mass in terms of polymethacrylate), obtained by the method of Synthesis Example 1 of JP-A-2015-26050 120 parts by mass of the resulting cinnamic acid derivative, 20 parts by mass of tetrabutylammonium bromide as a catalyst, and 150 parts by mass of propylene glycol monomethyl ether acetate as a diluting solvent were allowed to react with stirring at 90 ° C. for 12 hours in a nitrogen atmosphere. went. After completion of the reaction, 100 parts by mass of propylene glycol monomethyl ether acetate was added to the reaction mixture for dilution, and this was washed with water three times. The organic phase after washing with water was poured into a large excess of methanol to precipitate a polymer, and the collected precipitate was vacuum-dried at 40 ° C. for 12 hours to obtain the following polymer A1 having a photo-alignment group. .

<Polymer A2>
In a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel and a reflux condenser, 100.0 parts by mass of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 500 parts by mass of methyl isobutyl ketone and 10 parts of triethylamine 0.0 parts by weight were charged and mixed at room temperature. Next, 100 parts by mass of deionized water was dropped from the dropping funnel over 30 minutes, and the mixture was reacted at 80 ° C. for 6 hours while mixing under reflux. After completion of the reaction, the organic phase is taken out, washed with 0.2% by mass ammonium nitrate aqueous solution until the water after washing becomes neutral, and then the solvent and water are distilled off under reduced pressure to obtain an epoxy-containing polyorganosiloxane. Obtained as a viscous clear liquid.
When this epoxy-containing polyorganosiloxane was subjected to ¹ H-NMR analysis, a peak based on the oxiranyl group was obtained in the vicinity of chemical shift (δ) = 3.2 ppm according to the theoretical intensity. Was confirmed not to happen. The epoxy-containing polyorganosiloxane had a weight average molecular weight Mw of 2,200 and an epoxy equivalent of 186 g / mol.

  Next, in a 100 mL three-necked flask, 10.5 parts by mass of the epoxy-containing polyorganosiloxane obtained above, acrylic group-containing carboxylic acid (trade name “Aronix M-5300” manufactured by Toagosei Co., Ltd., acrylic acid ω-carboxyl) 0.4 parts by weight of polycaprolactone (polymerization degree n≈2), 20 parts by weight of butyl acetate, 0.5 parts by weight of cinnamic acid derivative obtained by the method of Synthesis Example 1 of JP-A-2015-26050, tetrahydrofoam 0.5 parts by mass of viscous mucoic acid (manufactured by Wako Pure Chemical Industries, Ltd.) and 0.3 parts by mass of tetrabutylammonium bromide were added and stirred at 90 ° C. for 12 hours. After completion of the reaction, the reaction solution was diluted with an equal amount (mass) of butyl acetate and washed with water three times. The operation of concentrating this solution and diluting with butyl acetate was repeated twice, and finally a solution containing a polyorganosiloxane having a photo-alignment group (polymer A2) was obtained. The weight average molecular weight Mw of the polymer A2 was 10,000.

[Synthesis of low molecular compound B]
<Low molecular compound B1>
Methoxycinnamic acid (3.56 g, 20 mmol), 2-hexyl-1-decanol (4.8 g, 20 mmol) and dimethylaminopyridine (0.2 g, 2 mmol) are dissolved in 30 ml of tetrahydrofuran (hereinafter abbreviated as “THF”). And stirred at 0 ° C.
To the above THF solution, dicyclohexylcarbodiimide (4.126 g, 20 mmol) was added and stirred at room temperature for 6 hours.
Next, THF was distilled off, 150 ml of ethyl acetate was added, and the precipitated solid was removed by filtration. After washing with 30 ml of ethyl acetate, ethyl acetate contained in the filtrate was distilled off to obtain 8 g of a crude product. The crude product was isolated and purified with a silica gel column (hexane / ethyl acetate = 3/1) to obtain a low molecular compound B1 represented by the following formula.

<Low molecular compound B2>
A low molecular compound B2 (NOMCOAT TAB, manufactured by Nisshin Orio Corporation) represented by the following formula was used.

[Crosslinking agent C]
A polyfunctional epoxy compound (Epolide GT401, manufactured by Daicel Corporation) was used as the crosslinking agent C1.

[Compound D1]
For the purpose of promoting crosslinking, a thermal acid generator (Sun-Aid SI-60, Sanshin Chemical Industry Co., Ltd.) was used as compound D1.

[Compound E1]
A 100 mL autoclave was charged with 10 parts by weight of Nomcoat TAB (manufactured by Nisshin Oilio Co., Ltd.), 20 parts by weight of butyl acetate, and 5 parts by weight of palladium activated carbon. After completion of the reaction, the reaction solution was filtered through Celite, and the filtrate was washed with water three times. The solution was concentrated, and chromatographic purification (silica gel, ethyl acetate / hexane mixed eluent) was repeated twice. Finally, p-methoxyphenylpropionic acid having no photo-alignment group represented by the following formula E1 2-Ethylhexyl (hereinafter referred to as “Compound E1”) was obtained.

[Examples 1-11 and Comparative Examples 1-2]
[Preparation of composition for photo-alignment film]
After adding and stirring the polymer A, the low molecular weight compound B, etc. in parts by mass shown in Table 1 below with respect to butyl acetate, the mixture is filtered with a filter having a pore size of 1 μm, so that the solid content concentration is 7.5% by weight. A liquid crystal aligning agent was prepared. In the obtained liquid crystal aligning agent, the polymer A and other components were sufficiently dissolved in the solvent according to the amount added.

[Preparation of optically anisotropic layer forming composition]
A coating liquid for optically anisotropic layer having the following composition (liquid crystals 1 to 4) was prepared.

─────────────────────────────────
Coating liquid for optically anisotropic layer (liquid crystal 1)
─────────────────────────────────
-80.00 parts by mass of the following liquid crystalline compound L-1-20.00 parts by mass of the following liquid crystalline compound L-2-Polymerization initiator (IRGACURE 184, manufactured by BASF)
3.00 parts by mass / polymerization initiator (IRGACURE OXE-01, manufactured by BASF)
3.00 parts by mass, leveling agent (compound G-1 below) 0.20 parts by mass, 424.8 parts by mass of methyl ethyl ketone ――――――――――――――――――――――― ――――――――――

―――――――――――――――――――――――――――――――――
Coating liquid for optically anisotropic layer (liquid crystal 2)
―――――――――――――――――――――――――――――――――
-42.00 parts by mass of the following liquid crystalline compound L-3-42.00 parts by mass of the following liquid crystalline compound L-4-16.00 parts by mass of the following polymerizable compound A-1-The following polymerization initiator S-1 (oxime type) ) 0.50 parts by mass / leveling agent (compound G-1) 0.20 parts by mass / high-solve MTEM (manufactured by Toho Chemical Co., Ltd.) 2.00 parts by mass / NK ester A-200 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 1.00 parts by mass ・ Methyl ethyl ketone 424.8 parts by mass ――――――――――――――――――――――――――――――――――
In addition, the group adjacent to the acryloyloxy group of the following liquid crystalline compounds L-3 and L-4 represents a propylene group (a group in which a methyl group is substituted with an ethylene group), and the following liquid crystalline compounds L-3 and L-4 Represents a mixture of positional isomers having different methyl group positions.

―――――――――――――――――――――――――――――――――
Coating liquid for optically anisotropic layer (liquid crystal 3)
―――――――――――――――――――――――――――――――――
-42.00 parts by mass of the liquid crystalline compound L-3-42.00 parts by mass of the liquid crystalline compound L-4-16.00 parts by mass of the polymerizable compound A-1-The polymerization initiator S-1 (oxime type) ) 0.50 parts by mass / leveling agent (compound G-1) 0.15 parts by mass / leveling agent (compound G-2) 0.15 parts by mass / highsolv MTEM (manufactured by Toho Chemical Co., Ltd.) 2.00 mass・ NK Ester A-200 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 1.00 parts by mass ・ Methyl ethyl ketone 424.8 parts by mass ―――――――――――――――――――――――― ――――――――――

―――――――――――――――――――――――――――――――――
Coating liquid for optically anisotropic layer (liquid crystal 4)
―――――――――――――――――――――――――――――――――
-42.00 parts by mass of the liquid crystalline compound L-3-42.00 parts by mass of the liquid crystalline compound L-4-16.00 parts by mass of the polymerizable compound A-1-The polymerization initiator S-1 (oxime type) ) 0.50 parts by mass / leveling agent (compound G-1) 0.15 parts by mass / leveling agent (compound G-3) 0.15 parts by mass / highsolv MTEM (manufactured by Toho Chemical Co., Ltd.) 2.00 mass・ NK Ester A-200 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 1.00 parts by mass ・ Methyl ethyl ketone 424.8 parts by mass ―――――――――――――――――――――――― ――――――――――

[Production of Cellulose Acylate Film 1]
(Preparation of core layer cellulose acylate dope)
The following composition was put into a mixing tank and stirred to dissolve each component to prepare a cellulose acetate solution used as a core layer cellulose acylate dope.
─────────────────────────────────
Core layer cellulose acylate dope─────────────────────────────────
Cellulose acetate having an acetyl substitution degree of 2.88 100 parts by mass Polyester compound B described in Examples of JP-A-2015-227955 12 parts by mass The following compound F 2 parts by mass Methylene chloride (first solvent) 430 parts by mass Methanol (Second solvent) 64 parts by mass ──────────────────────────────────

(Preparation of outer layer cellulose acylate dope)
10 parts by mass of the following matting agent solution was added to 90 parts by mass of the core layer cellulose acylate dope to prepare a cellulose acetate solution used as an outer layer cellulose acylate dope.
─────────────────────────────────
Matting agent solution ─────────────────────────────────
Silica particles having an average particle size of 20 nm (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) 2 parts by mass Methylene chloride (first solvent) 76 parts by mass Methanol (second solvent) 11 parts by mass The above core layer cellulose acylate dope 1 mass ──────────────────────────────────

(Preparation of cellulose acylate film 1)
The core layer cellulose acylate dope and the outer layer cellulose acylate dope are filtered through a filter paper having an average pore size of 34 μm and a sintered metal filter having an average pore size of 10 μm, and then the core layer cellulose acylate dope and the outer layer cellulose acylate dope on both sides thereof 3 layers were simultaneously cast on a drum at 20 ° C. from a casting port (band casting machine). The film was peeled off at a solvent content of about 20% by mass, both ends in the width direction of the film were fixed with tenter clips, and dried while being stretched in the transverse direction at a stretch ratio of 1.1. Then, it further dried by conveying between the rolls of a heat processing apparatus, produced the optical film with a thickness of 40 micrometers, and made this the optical film of Example 1. The core layer of the optical film of Example 1 had a thickness of 36 μm, and the outer layers disposed on both sides of the core layer had a thickness of 2 μm. The in-plane retardation of the obtained cellulose acylate film 1 was 0 nm.

(Production of optical laminate)
Each composition for photo-alignment films prepared above was applied to one surface of the produced cellulose acylate film 1 with a bar coater.
After coating, the solvent was removed by drying on a hot plate at 120 ° C. for 1 minute to form a photoisomerized composition layer having a thickness of 0.3 μm.
The obtained photoisomerizable composition layer was irradiated with polarized ultraviolet rays (10 mJ / cm ² , using an ultrahigh pressure mercury lamp) to form a photo-alignment film.
Next, the liquid crystal 1 or 2 (the composition for forming an optically anisotropic layer) prepared previously was applied on the photo-alignment film with a bar coater to form a composition layer.
The formed composition layer was once heated to 110 ° C. on a hot plate and then cooled to 60 ° C. to stabilize the orientation.
Thereafter, the orientation is fixed by irradiation with ultraviolet rays (500 mJ / cm ² , using an ultra-high pressure mercury lamp) in a nitrogen atmosphere (oxygen concentration 100 ppm) under a nitrogen atmosphere to form an optically anisotropic layer having a thickness of 2.3 μm. An optical laminate was produced. The in-plane retardation of the obtained optical laminated body was 140 nm.

<Absorption ratio>
After forming a photo-alignment film on the cellulose acylate film 1, methyl ethyl ketone was applied by spin coating method simulating liquid crystal application and dried to prepare a laminate sample.
Using an ultraviolet-visible near-infrared spectrophotometer (V-7200 manufactured by JASCO Corporation) equipped with a Glan-Thompson polarizer, linearly polarized measurement light was incident, and the absorbance at a wavelength of 290 nm of the prepared laminate sample was measured. . The absorbance of the cellulose acylate film 1 was subtracted from the measured value to determine the absorbance of the photoalignment film alone.
The absorption ratio (Ac / Ap) was determined with Ap as the absorbance in the direction parallel to the polarization direction of the polarized ultraviolet light irradiated during the preparation of the photo-alignment film and Ac as the absorbance in the orthogonal direction. The results are shown in Table 1 below. The higher the absorption ratio, the higher the degree of orientation.

<Orientation>
About the produced optical laminated body, it observed in the state shifted | deviated twice from the quenching position using the polarizing microscope. As a result, the following criteria were evaluated. The results are shown in Table 1 below.
AAA: The liquid crystal director is finely aligned and aligned, and the display performance is very excellent. AA: The liquid crystal director is uniformly aligned and aligned, and the display performance is excellent. A: The liquid crystal director is not disturbed and the surface state is stable. B : Disturbance of the liquid crystal director is negligible and the surface is stable. C: Disturbance of the liquid crystal director is partial and the surface is stable. D: The liquid crystal director is greatly disturbed and the surface is stable. Display performance is very poor

From the results shown in Table 1, it was found that when only the polymer A was blended and prepared without blending the low molecular compound B, the orientation was inferior (Comparative Examples 1 and 2).
On the other hand, when it prepared by mix | blending both the polymer A and the low molecular compound B, it turned out that orientation becomes favorable (Examples 1-11).
In particular, from the comparison of Examples 1 to 4, it was found that the content of the low molecular compound B was 50 to 500% by mass with respect to the mass of the polymer A, and the orientation became better.
Further, from the comparison between Examples 7 and 8, it was found that the orientation was further improved when the optically anisotropic layer was formed of a liquid crystalline compound exhibiting smectic properties.

[Evaluation of anti-reflection plate (circular polarizing plate) for organic EL]
(Preparation of positive C plate film 1)
As a temporary support, a commercially available triacetyl cellulose film “Z-TAC” (manufactured by FUJIFILM Corporation) was used (this is referred to as cellulose acylate film 2). After passing the cellulose acylate film 2 through a dielectric heating roll having a temperature of 60 ° C. and raising the film surface temperature to 40 ° C., the coating amount of an alkali solution having the composition shown below is applied to one side of the film using a bar coater. It was applied at 14 ml / m @ 2, heated to 110 DEG C., and conveyed for 10 seconds under a steam far infrared heater manufactured by Noritake Company Limited. Subsequently, 3 ml / m 2 of pure water was applied using the same bar coater. Next, washing with a fountain coater and draining with an air knife were repeated three times, and then the sheet was transported to a drying zone at 70 ° C. for 10 seconds and dried to prepare an alkali saponified cellulose acylate film 2.
─────────────────────────────────
Composition of alkaline solution (parts by mass)
─────────────────────────────────
Potassium hydroxide 4.7 parts by weight Water 15.8 parts by weight Isopropanol 63.7 parts by weight Fluorine-containing surfactant SF-1
(C ₁₄ H ₂₉ O (CH ₂ CH ₂ O) ₂₀ H) 1.0 part by mass propylene glycol 14.8 parts by mass ────────────────────── ───────────

Using the above-described alkali saponified cellulose acylate film 2, a coating solution for forming an alignment film having the following composition was continuously applied with a # 8 wire bar. The alignment film was formed by drying with warm air of 60 ° C. for 60 seconds and further with warm air of 100 ° C. for 120 seconds.
─────────────────────────────────
Composition of coating solution for alignment film C formation ──────────────────────────────────
Polyvinyl alcohol (manufactured by Kuraray, PVA103) 2.4 parts by mass Isopropyl alcohol 1.6 parts by mass Methanol 36 parts by mass Water 60 parts by mass ────────────────────── ───────────

The following coating liquid N is applied on the cellulose acylate film 2 having an alignment film prepared as described above, and after aging at 60 ° C. for 60 seconds, an air-cooled metal halide lamp of 70 mW / cm 2 under air (Igraphics Corporation) )) Was used to irradiate ultraviolet rays of 1000 mJ / cm 2 to fix the alignment state, whereby the polymerizable rod-like liquid crystal compound was vertically aligned, and a positive C plate film 1 was produced. Rth was −60 nm at a wavelength of 550 nm.
─────────────────────────────────
Composition of coating liquid N for optically anisotropic film ──────────────────────────────────
Liquid crystal compound L-1 80 parts by mass Liquid crystal compound L-2 20 parts by mass Vertical alignment liquid crystal compound (S01) 1 part by mass Vertical alignment agent (S02) 0.5 parts by mass Ethylene oxide-modified trimethylolpropane triacrylate (V # 360, manufactured by Osaka Organic Chemical Co., Ltd.) 8 parts by mass Irgacure 907 (manufactured by BASF) 3 parts by mass Kayacure DETX (manufactured by Nippon Kayaku Co., Ltd.) 1 part by mass Compound B03 0.4 parts by mass methyl ethyl ketone 170 parts by mass cyclohexanone 30 Mass part ──────────────────────────────────

(Production of circularly polarizing plate)
(Example 71)
The positive C plate film 1 prepared above was transferred to the optically anisotropic layer side of the optical laminate of Example 7 via an adhesive, and the cellulose acylate film 2 was removed. Further, a polarizing plate was bonded to the cellulose acylate film 1 side of the optical laminate through an adhesive to obtain a circularly polarizing plate.

(Mounting and evaluation on organic EL panels)
Next, disassemble GALAXY SII manufactured by SAMSUNG equipped with an organic EL panel, peel off the circularly polarizing plate, and paste it with an adhesive so that the circularly polarizing plate created above and the positive C plate side become the panel side. A display device was manufactured.
White, black, and image display were performed on the display device, and reflected light when a fluorescent lamp was projected from a polar angle of 60 degrees was observed, and the display quality was evaluated according to the following criteria.
A: Black float is not visually recognized at all (excellent).
B: Although the black float is visually recognized slightly, it is permissible (acceptable).
C: The black float is clearly visible.

(Example 81, Example 91, Comparative Example 101)
In place of the optical laminate of Example 7, those using the optical laminate of Example 8, Example 9, and Comparative Example 1 were mounted and evaluated as Example 81, Example 91, and Comparative Example 101, respectively. . The results are shown in Table 2.

  From the results shown in Table 2, it is clear that the optical laminate formed using the photo-alignment film of the present invention brings about a significant improvement in display function even when used in an organic EL display device.

DESCRIPTION OF SYMBOLS 1 Optical alignment film 2 Optical anisotropic layer 2a 1st optical anisotropic layer 2b 2nd optical anisotropic layer 3 Support body 3a Polarizer 3b Polymer film 10, 20, 30, 40 Optical laminated body

Claims (10)

A polymer A having a structural unit a1 containing a cinnamate group;
A composition for a photoalignment film, comprising a low molecular compound B having a cinnamate group and having a molecular weight smaller than that of the polymer A.   The composition for photoalignment films according to claim 1 whose molecular weight of said low molecular compound B is 200-500.   The composition for photo-alignment films according to claim 1 or 2, wherein the content of the low-molecular compound B is 10 to 500% by mass with respect to the mass of the structural unit a1 of the polymer A. The composition for photo-alignment films according to any one of claims 1 to 3, wherein the low-molecular compound B is a compound represented by the following formula (B1).

In the formula (B1), a represents an integer of 0 to 5, R ¹ represents a hydrogen atom or a monovalent organic group, and R ² represents a monovalent organic group. When a is 2 or more, the plurality of R ¹ may be the same or different from each other.   The composition for photo-alignment films according to any one of claims 1 to 4, wherein the polymer A further has a structural unit a2 containing a crosslinkable group.   Furthermore, the composition for photo-alignment films of any one of Claims 1-5 containing the crosslinking agent C which has a crosslinkable group. It produces using the composition for photo-alignment films of any one of Claims 1-6,
A photo-alignment film having a structure in which the cinnamate group of the polymer A and the low-molecular compound B contained in the photo-alignment composition is dimerized and / or the cinnamate group is isomerized.   An optical laminate comprising the photo-alignment film according to claim 7 and an optically anisotropic layer provided on the photo-alignment film and containing a liquid crystalline compound.   The optical laminate according to claim 8, comprising a support, the photo-alignment film, and the optically anisotropic layer in this order.   An image display device comprising the optical laminate according to claim 8.