TW202242459A - Polarizing element and manufacturing method therefor which is less susceptible to peeling when bent - Google Patents

Abstract

An objective of the invention is to provide a polarizing element which is less susceptible to peeling when bent. The polarizing element of the present invention is formed by sequentially laminating a base material, an alignment film, and a polarizing film. The alignment film is formed by curing an alignment film-forming composition, and the alignment film-forming composition comprises an alignment polymer (A-1) and a compound (A-2) having an active hydrogen-reactive group.

Description

Polarizing element and manufacturing method thereof

The present invention relates to a polarizing element, a method for manufacturing the above-mentioned polarizing element, a flat panel display device and a flexible display material including the above-mentioned polarizing element.

Polarizing plates are used in image display devices represented by organic electroluminescent (hereinafter, also referred to as organic EL) display devices, bonded to image display elements such as liquid crystal cells or organic EL display elements. In recent years, as such image display devices have been required to be thinner, further thinning of polarizing plates or polarizing films, which are one of their constituent elements, has also been required. Various polarizing plates or polarizing films have been proposed to meet this demand. For example, Patent Document 1 discloses an ultra-thin polarizing element in which a polarizing layer in which a polymerizable liquid crystal compound and a dichroic dye are aligned via a photoalignment layer is provided on a substrate. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 2017-102479

[Problem to be Solved by the Invention]

It is expected that the ultra-thin polarizing element can be preferably used in flexible displays and the like. However, if the bending diameter becomes smaller, peeling of the polarizing film or the like may occur at the bent portion, and therefore a polarizing element with high bending resistance that is more suitable for use in flexible displays is required.

The purpose of the present invention is to provide a polarizing element that is not easy to be peeled off when bent. [Technical means to solve the problem]

The inventors of the present invention conducted earnest research in order to solve the above-mentioned problems, and as a result completed the present invention. That is, the present invention includes the following aspects. [1] A polarizing element comprising sequentially laminating a base material, an alignment film, and a polarizing film, wherein the alignment film is formed by curing an alignment film-forming composition, and the alignment film-forming composition includes an alignment property A polymer (A-1), and a compound (A-2) having an active hydrogen reactive group. [2] The polarizing element according to the above [1], wherein the polarizing film is obtained by curing the composition for forming a polarizing film, and the composition for forming a polarizing film contains a polymerizable liquid crystal compound (B-1), A compound (B-2) having an active hydrogen reactive group, and a dichroic dye (B-3). [3] The polarizing element according to the above [1] or [2], wherein the compound (A-2) further has an active hydrogen-containing group. [4] The polarizing element according to any one of [1] to [3] above, wherein the alignment polymer (A-1) is a polymer having a photoreactive group that causes a dimerization reaction. [5] The polarizing element according to any one of the above [1] to [4], wherein the alignment polymer (A-1) is a (meth)acrylic polymer. [6] The polarizing element according to any one of [1] to [5] above, wherein the weight average molecular weight of the alignment polymer (A-1) is not less than 10,000 and not more than 1,000,000. [7] The polarizing element according to any one of [1] to [6] above, wherein the compound (A-2) is a silane coupling agent. [8] The polarizing element described in any one of the above [1] to [7], wherein the compound (A-2) is selected from the group consisting of primary amine groups, secondary amine groups, hydroxyl groups, and mercapto groups. A silane coupling agent with at least one functional group. [9] The polarizing element according to any one of the above [1] to [8], wherein the content of the compound (A-2) is 1 part by mass or more with respect to 100 parts by mass of the alignment polymer (A-1) 30 parts by mass or less. [10] The polarizing element according to any one of [2] to [9] above, wherein the compound (B-2) further has a polymerizable group. [11] The polarizing element according to the above [10], wherein the polymerizable group is a (meth)acryl group. [12] The polarizing element according to any one of [2] to [11] above, wherein the compound (B-2) has one or more isocyanate groups and one or more (meth)acryl groups, respectively. base. [13] The polarizing element according to any one of [2] to [12] above, wherein the content of the compound (B-2) is 0.1 parts by mass or more based on 100 parts by mass of the polymerizable liquid crystal compound (B-1) 12 parts by mass or less. [14] The polarizing element according to any one of [2] to [13] above, wherein the dichroic dye (B-3) contains a compound represented by the formula (I): K ¹ (-N=NK ² ) _p -N=NK ³ (I) [In the formula (I), K ¹ and K ³ independently represent a phenyl group that may have a substituent, a naphthyl group that may have a substituent, and a benzoic acid benzene group that may have a substituent An ester group or a valent heterocyclic group that may have a substituent, K2 represents a ^p -phenylene group that may have a substituent, a naphthalene-1,4-diyl group that may have a substituent, and 4,4' that may have a substituent - a stilbene group or a divalent heterocyclic group that may have a substituent, p represents an integer of 0 to 4, and when p is an integer of 2 or more, the plurality of K ² may be the same or different from each other, in the range of visible light Within the range of performance absorption, -N=N-bonds can be replaced by -C=C-, -COO-, -NHCO-, -N=CH-bonds]. [15] The polarizing element according to any one of [2] to [14] above, wherein the polymerizable liquid crystal compound (B-1) is a liquid crystal compound exhibiting smectic liquid crystallinity. [16] The polarizing element according to any one of [1] to [15] above, wherein the substrate has a thickness of not less than 1 μm and not more than 10 μm. [17] The polarizing element according to any one of [1] to [16] above, wherein the surface of the polarizing film opposite to the alignment film includes an overcoat layer. [18] A manufacturing method, which is a method of manufacturing a polarizing element formed by sequentially laminating a substrate, an alignment film, and a polarizing film, comprising the following steps: (1) forming an alignment polymer ( A-1) and a coating film of a composition for forming an alignment film of a compound (A-2) having an active hydrogen reactive group, and drying the coating film, thereby deactivating the active hydrogen contained in the compound (A-2) The reactive group reacts with the polar group of the substrate to form a bond; (2) forming an alignment film by performing rubbing treatment or light irradiation on the dried coating film obtained in step (1); (3) in step (2) ) forming a composition for forming a polarizing film comprising a polymerizable liquid crystal compound (B-1), a compound having an active hydrogen reactive group (B-2) and a dichroic dye (B-3) on the alignment film obtained coating film, and drying the coating film; and (4) making the polymerizable liquid crystal compound (B-1) and dichroic pigment (B-3) in the dry coating film obtained in step (3) in an aligned state hardened to form a polarizing film. [19] The production method described in [18] above, further comprising: a step of forming an overcoat layer on the polarizing film formed in step (4). [20] A flat panel display device comprising the polarizing element according to any one of the above [1] to [17]. [21] A flexible display material comprising the polarizing element described in any one of the above-mentioned [1] to [17]. [Effect of Invention]

According to the present invention, it is possible to provide a polarizing element that does not easily peel off when bent.

Embodiments of the present invention will be described in detail below. In addition, the range of this invention is not limited to embodiment demonstrated here, Various changes are possible in the range which does not damage the summary of this invention.

The polarizing element of the present invention sequentially comprises a base material, an alignment film and a polarizing film. In the polarizing element of the present invention, it is preferable that the substrate, the alignment film, and the polarizing film be adjacent to each other as a structure that can more easily achieve the effect of the present invention. As long as the effect of the present invention is not affected, the polarizing element of the present invention may further include other layers in addition to the base material, alignment film, and polarizing film. Examples of other layers include an overcoat layer provided on a polarizing film, an adhesive layer for bonding to image display elements such as a liquid crystal cell or an organic EL display element, and the like.

＜Alignment film＞ The polarizing device of the present invention includes an alignment film formed by curing a composition for forming an alignment film. The composition for forming an alignment film includes an alignment polymer (A-1) and a compound having an active hydrogen reactive group (A- 2). In the present invention, the alignment film has the alignment restriction force to make the following polymerizable liquid crystal compounds or dichroic pigments that constitute the polarizing film align the liquid crystals in the desired direction. Composition of polarizing films such as liquid crystal compounds can easily obtain polarizing films with high precision alignment.

Regarding the state of liquid crystal alignment such as horizontal alignment, vertical alignment, hybrid alignment, and oblique alignment, the state of liquid crystal alignment such as horizontal alignment, vertical alignment, hybrid alignment, and oblique alignment can be controlled according to the properties of the alignment film and the polymerizable liquid crystal compound. In the invention, the combination can be selected arbitrarily according to the desired alignment state. For example, by using an alignment film formed of a material exhibiting horizontal alignment as an alignment limiting force, the polymerizable liquid crystal compound can be aligned horizontally or mixed, and by using an alignment film formed of a material exhibiting vertical alignment as an alignment limiting force film, which can align the polymerizable liquid crystal compound vertically or obliquely. In addition, alignment directions such as horizontal alignment and vertical alignment mean the long axis direction of the polymerizable liquid crystal compound aligned when the plane of the polarizing film is taken as a reference. For example, horizontal alignment refers to the state of aligning the long axis direction of the polymerizable liquid crystal compound in the direction parallel to the plane of the polarizing film, and vertical alignment refers to the state of aligning the polymerizable liquid crystal in the direction perpendicular to the plane of the polarizing film. The state of the long axis direction of the compound. Here, horizontal to the plane of the polarizing film means 0°±20° relative to the plane of the polarizing film, and vertical means 90°±20° relative to the plane of the polarizing film.

In this invention, an alignment film is formed from the composition for alignment film formation containing an alignment polymer (A-1). Regarding the alignment restriction force of the alignment film, the alignment film can be arbitrarily controlled by the surface state or rubbing state, polarized light irradiation conditions, etc. according to the type of the alignment polymer (A-1) contained in the composition for forming the alignment film. Alignment constraints. In addition, liquid crystal alignment can also be controlled by selecting physical properties such as surface tension and liquid crystallinity of the polymerizable liquid crystal compound.

As an alignment film, it is insoluble in a solvent used for forming a polarizing film on an alignment film, and preferably has heat resistance for solvent removal or heat treatment for liquid crystal alignment. The alignment film may, for example, be a rubbed alignment film formed of an alignment polymer, a photo-alignment film, or a groove alignment film. In one embodiment of the present invention, the alignment film is preferably a photo-alignment film in terms of easy control of the alignment direction during manufacture of the polarizing element, and excellent alignment angle accuracy and quality.

When the alignment film is a rubbed alignment film formed of an alignment polymer, examples of the alignment polymer (A-1) include: polyamide or gelatin having an amide bond in the molecule, molecular Polyamide acid, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, polyoxazole, polyethylene imine, poly Styrene, polyvinylpyrrolidone, polyacrylic acid and polyacrylates, etc. Hereinafter, the alignment polymer for rubbing alignment films is also referred to as "rubbing alignment polymer". Among them, polyvinyl alcohol is preferable as the rubbing alignment polymer. The rubbing alignment polymer may be used alone or in combination of two or more.

When the alignment film is a photo-alignment film, the alignment polymer (A-1) is usually an alignment polymer having a photoreactive group. Hereinafter, the alignment polymer for forming a photo-alignment film is also referred to as a "photo-alignment polymer". In this specification, the photoreactive group refers to the group that generates liquid crystal alignment energy by light irradiation. In the polymer forming the photoalignment film, the photoreactive group helps to impart liquid crystal alignment energy through the action of light. . Specifically, it means that the alignment of polymer molecules is induced by photoreactions such as dimerization reactions, isomerization reactions, photocrosslinking reactions, or photodecomposition reactions that become the origin of liquid crystal alignment energy by light irradiation. base. The photoreactive group which a photoalignment polymer has may be 1 type, and may be 2 or more types.

As the photoreactive group that can cause the reaction as described above, those with unsaturated bonds, especially those with double bonds are preferred, for example, those with a carbon-carbon double bond (C=C bond), A base of at least one of the group consisting of carbon-nitrogen double bond (C=N bond), nitrogen-nitrogen double bond (N=N bond) and carbon-oxygen double bond (C=O bond).

As a group which has a C=C bond, a vinyl group, a polyalkenyl group, a stilbene group, a styrylpyridyl group, a styrylpyridinium group, a chalcone group, a cinnamoyl group etc. are mentioned, for example. As a group which has a C=N bond, the group which has structures, such as an aromatic Schiff base and an aromatic hydrazone, is mentioned, for example. As the group having an N=N bond, for example, azophenyl group, azonaphthyl group, aromatic heterocyclic azo group, disazo group, formazan group, and azobenzene oxide as the basic structure By. As a group which has a C=O bond, a benzophenone group, a coumarin group, an anthraquinone group, a maleimide group, etc. are mentioned. These groups may also have substituents such as alkyl, alkoxy, aryl, allyloxy, cyano, alkoxycarbonyl, hydroxyl, sulfonic acid, and halogenated alkyl. Among them, from the viewpoint of excellent alignment or reactivity, the photoalignment polymer preferably has a photoreactive group that causes a dimerization reaction or a photocrosslinking reaction, and more preferably has a photoreactive group that causes a dimerization reaction. base.

The dimerization reaction is an addition reaction between two groups by the action of light, and typically refers to a reaction in which a ring structure is formed. As the group that causes the dimerization reaction, a group including a carbon-carbon double bond (C=C bond) or a carbon-oxygen double bond (C=O bond) that causes a dimerization reaction by light irradiation, For example, a group having a cinnamyl structure, a group having a chalcone structure, a group having a coumarin structure, a group having a benzophenone structure, a group having an anthracene structure, etc. may be mentioned. Among them, in terms of easy control of reactivity and excellent alignment restriction force during photo-alignment, groups having a cinnamoyl structure and a group having a chalcone structure are preferred, and those having a cinnamoyl structure are more preferred. base. In addition, the group having the above structure is also advantageous in terms of easily obtaining a photoalignment film that requires relatively less amount of polarized light irradiation required for photoalignment and is excellent in thermal stability or temporal stability.

The photo-alignment polymer preferably has a photoreactive group that produces a dimerization reaction at the end of the polymer side chain, and more preferably has a group containing a cinnamoyl structure or a chalcone structure at the end of the polymer side chain It is more preferable to have a group containing a cinnamoyl structure at the end of the polymer side chain. As the photo-alignment polymer, for example, a polymer whose side chain has a structure represented by the following formula (A1') and/or a structure represented by the formula (A1'') (hereinafter, these collectively referred to as "photo-alignment polymer (A)").

[式(A1')及式(A1'')中， k表示0或1。 L ¹表示單鍵或-O-。 L ²表示單鍵、-O-、-COO-、-OCO-、-N=N-、-CH=CH-或-CH ₂-。 R ¹、R ²及R ³分別獨立地表示氫原子、鹵素原子、鹵化烷基、鹵化烷氧基、氰基、硝基、烷基、烷氧基、芳基、烯丙氧基、烷氧基羰基、羧基、磺酸基、胺基或羥基，該羧基及該磺酸基亦可與鹼金屬離子形成鹽。 R ⁴表示氫原子、烷基或苯基。 *表示對聚合物主鏈之鍵結鍵] [chemical 1]

[In formula (A1') and formula (A1''), k represents 0 or 1. L ¹ represents a single bond or -O-. L ² represents a single bond, -O-, -COO-, -OCO-, -N=N-, -CH=CH- or -CH ₂ -. R ¹ , R ² and R ³ independently represent hydrogen atom, halogen atom, halogenated alkyl, halogenated alkoxy, cyano, nitro, alkyl, alkoxy, aryl, allyloxy, alkoxy Carbonyl group, carboxyl group, sulfonic acid group, amino group or hydroxyl group, the carboxyl group and the sulfonic acid group can also form salts with alkali metal ions. R ⁴ represents a hydrogen atom, an alkyl group or a phenyl group. *Indicates a bond to the polymer backbone]

L ² in formula (A1') and formula (A1'') is any one of -O-, -COO-, -OCO-, -N=N-, -C=C- and -CH ₂ - In this case, it is easy to produce the photo-alignment polymer (A).

R ¹ , R ² and R ³ in formula (A1') and formula (A1'') are preferably each independently a hydrogen atom, an alkyl group with 1-4 carbons, or an alkoxy group with 1-4 carbons. Examples of alkyl groups represented by R ¹ , R ² and R ³ include methyl, ethyl, and butyl groups, and examples of alkoxy groups include methoxy, ethoxy, and butoxy groups. .

The main chain of the photo-alignment polymer (A) is not particularly limited. As the structure of the monomer units forming the main chain, for example, it can be selected from the group consisting of the following units: formula (M-1) or The (meth)acrylate unit represented by formula (M-2); the (meth)acrylamide unit represented by formula (M-3) or formula (M-4); the formula (M-5) or formula Vinyl ether unit represented by (M-6); (methyl)styrene unit represented by formula (M-7) or formula (M-8), and formula (M-9) or formula (M-10) Represented vinyl ester units. In formulas (M-1) to (M-10), * represents a bond with the structure represented by formula (A1') or formula (A1''), or represents a bond with the following spacer unit key. Furthermore, in this specification, "the main chain of the photo-alignment polymer (A)" refers to the longest molecular chain among the molecular chains of the photo-alignment polymer (A).

[Chem 2]

The main chain of the photo-alignment polymer (A) may be a homopolymer composed of one type of monomer unit, or may be a copolymer composed of two or more types of monomer units. In the case where the main chain of the photo-alignment polymer (A) is a copolymer, any bonding method such as alternating type, block type, random type, or graft type can be used.

Also, the structure of the monomer unit forming the main chain of the photoalignment polymer (A) may be a silsesquioxane structure including repeating units represented by formulas (M-11) to (M-16). In formulas (M-11) to (M-16), * represents a bond with the structure represented by formula (A1') or formula (A1''), or represents a bond with the following spacer unit . [Chem 3]

In the formulas (M-11) to (M-16), R ⁵ represents an alkyl group having 1 to 6 carbons, an alkoxy group having 1 to 6 carbons, or one bonded to another silicon atom via an oxygen atom. The alkyl group having 1 to 6 carbon atoms represented by R ³ may, for example, be methyl, ethyl, n-propyl, isopropyl or n-butyl, among which methyl and ethyl are preferred. As the alkoxy group having 1 to 6 carbon atoms represented by R ⁵ , for example, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, etc., are preferred. Methoxy, Ethoxy.

In formulas (M-13) and (M-14), Ph represents a divalent benzene ring which may have a substituent (for example, a phenylene group, etc.). In formula (M-16), Cy may, for example, be a divalent cyclohexane ring which may have a substituent (for example, cyclohexane-1,4-diyl, etc.).

n represents an integer of 1-4.

The main chain of the photo-alignment polymer (A) preferably includes a structural unit represented by any one of formula (M-1) to formula (M-16), more preferably includes formula (M-1) to formula The structural unit represented by any one of (M-10) preferably includes (meth)acrylate units and (meth)acrylic ester units represented by formulas (M-1) to (M-4) A structural unit in the group consisting of acrylamide units.

As represented by any one of formulas (M-1) to (M-16), the monomer structural unit forming the main chain of the photoalignment polymer (A) can be directly combined with formula (A1') or formula (A1' ') can also be bonded via a linking group as an appropriate spacer unit. In the case of bonding via a linking group, the linking group may, for example, be a carbonyloxy group (ester bond), an oxygen atom (ether bond), an imine group, a carbonylimino group (amide bond), or an imine group. A carbonylimino group (urethane bond), a divalent aliphatic hydrocarbon group which may have a substituent, a divalent aromatic hydrocarbon group which may have a substituent, and a divalent group obtained by combining these, and the like. Examples of divalent aromatic hydrocarbon groups that may have substituents include: phenylene, 2-methoxy-1,4-phenylene, 3-methoxy-1,4-phenylene, 2- Ethoxy-1,4-phenylene, 3-ethoxy-1,4-phenylene, 2,3,5-trimethoxy-1,4-phenylene and the like. Among them, an aliphatic hydrocarbon group is preferable, and an alkanediyl group having 1 to 11 carbon atoms which may have a substituent is more preferable. Furthermore, as the alkanediyl group, methylene, ethylidene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, Nonamethylene, decamethylene, undecamethylene, and the like may be linear or branched. Moreover, as a substituent which this alkanediyl group may have, the alkoxy group etc. which have 1-4 carbon atoms are mentioned, for example.

The structure represented by formula (A1') preferably constitutes the photo-alignment polymer (A) as a structural unit represented by (A1-1) (hereinafter, also referred to as "structural unit (A1-1)"). In one embodiment of the present invention, the photo-alignment polymer (A) contains a structural unit (A1-1). Also, the structure represented by the formula (A1'') is preferably constituted by the photoalignment polymer (A) as a structural unit represented by (A1-2) (hereinafter also referred to as "structural unit (A1-2)") ), in one embodiment of the present invention, the photo-alignment polymer (A) includes a structural unit (A1-2). [chemical 4]

In formula (A1-1) and formula (A1-2), L ¹ , L ² , R ¹ , R ² , R ³ , R ⁴ and k are respectively the same as those in formula (A1') or formula (A1'') above They have the same meaning, SP ¹ is an alkanediyl group with 1 to 11 carbon atoms that may have a substituent, and the structure represented by M ¹ is represented by any one of formula (M-1) to formula (M-16). structure.

The photo-alignment polymer (A) may have a carboxyl group in addition to a photoreactive group, especially a photoreactive group that causes a dimerization reaction. The photoalignment polymer (A) having a photoreactive group and a carboxyl group may be, for example, a polymer comprising a structural unit (A1-1), and, as another aspect, for example, may also be constituted such that, in addition to comprising the formula (A1 '), the structure represented by formula (A1'') or structural unit (A1-1) and/or structural unit (A1-2), may also include the structure represented by formula (A1-3) unit (hereinafter also referred to as "structural unit (A1-3)"). [chemical 5]

In formula (A1-3), 1 represents 0 or 1, and SP ² represents an alkanediyl group having 1 to 11 carbon atoms which may have a substituent. The specific example of SP ² is the same as the specific example of SP ¹ in formula (A1-1) and formula (A1-2), and the structure represented by M ² is any of formula (M-1) to formula (M-16). The structure represented by one.

In formula (A1-3), L ³ represents a single bond or -O-, L ⁴ represents a single bond, -O-, -COO-, -OCO-, -N=N-, -CH=CH- or -CH ₂ -.

In the formula (A1-3), R ⁶ and R ⁷ independently represent a hydrogen atom, an alkyl group having 1 to 4 carbons, or an alkoxy group having 1 to 4 carbons. Examples of the alkyl group represented by ^R6 and ^R7 include methyl, ethyl, and butyl groups, and examples of the alkoxy group include methoxy, ethoxy, and butoxy groups.

In the case where the photoalignment polymer (A) is composed of a structural unit (A1-1) or (A1-2) and a structural unit (A1-3), the structural unit (A1-1) is compared to the constituent The molar fraction of the total structural units of the photoalignment polymer (A) is set to p, and the molar fraction of (A1-2) relative to the total structural units constituting the photoalignment polymer (A) is set to q , let the molar fraction of the structural unit (A1-3) relative to the total structural units constituting the photo-alignment polymer (A) be r (here, p+r is 1, and q+r is 1), in this case, Preferably, the relationships of 0.10<p, q≦0.90 and 0.10≦r<0.90 are satisfied. In the photo-alignment polymer containing the structural unit (A1-1), the structural unit (A1-1) may be one type, or two or more types. Also, regarding the photo-alignment polymer (A), as long as the liquid crystal alignment energy obtained by light irradiation is not significantly damaged, the photo-alignment polymer (A) may also have structural units other than (A1-1), (A1-2 ) and structural units other than structural units (A1-3) (hereinafter also referred to as "other structural units").

The photoalignment polymer (A) can be produced by making the monomer of the inducing structural unit (A1-1) or the structural unit (A1-2), and the optional inducing structural unit (A1-3 ) and/or monomer (co)polymerization of other structural units. As the method of copolymerization, methods known in the art can be used, for example, chain polymerization such as radical polymerization, anionic polymerization and cationic polymerization, and addition polymerization such as coordination polymerization can be used. The polymerization conditions can be appropriately determined according to the type and amount of the monomer used, etc., so that the photo-alignment polymer (A) having a desired molecular weight can be obtained.

In the present invention, the molecular weight of the alignment polymer (A-1) is preferably 10,000 to 1,000,000 in terms of weight average molecular weight in terms of polystyrene as measured by gel permeation chromatography (GPC). Below, more preferably 15,000 or more, still more preferably 20,000 or more, and more preferably 500,000 or less, still more preferably 250,000 or less. When the weight-average molecular weight of the alignment polymer (A-1) is within the above range, the solvent resistance is good, and after that, it is easy to ensure high adhesion with the polarizing film formed on the alignment film and to perform excellent liquid crystal alignment. capable alignment film.

In the present invention, the alignment polymer (A-1) is preferably a photo-alignment polymer, more preferably a photo-alignment polymer (A), and further preferably a (meth)acrylic polymer (especially (Meth)acrylic photo-alignment polymer (A)). Especially when the polymerizable liquid crystal compound forming the polarizing film is a compound having a (meth)acryl group as a polymerizable group, if the alignment polymer (A-1) is a (meth)acrylic polymer, Then, the affinity is excellent, and even in the case of a small bending diameter, it is expected that the bending resistance to suppress peeling of the polarizing film and the alignment film can be further improved. Furthermore, in this specification, the ratio of structural units based on (meth)acrylic structures such as (meth)acrylate units or (meth)acrylamide units among the total structural units constituting the polymer main chain is The largest polymers are collectively referred to as "(meth)acrylic polymers".

Regarding the content of the alignment polymer (A-1) in the composition for forming an alignment film, the composition for forming an alignment film can be appropriately determined according to the type of alignment polymer used, the thickness of the alignment film required, etc. The content of the alignment polymer (A-1) in the product. The alignment polymer (A-1) used is not particularly limited if it is in a completely soluble amount, but its content (concentration) is preferably 1.0 to 25.0 mass with respect to the total mass of the composition for forming an alignment film %, more preferably 2.5 to 22.5% by mass. In the composition for forming an alignment film, the alignment polymer (A-1) may be one type alone, or two or more types may be combined. When two or more types are included, the total content thereof is preferably within the above-mentioned within range.

In the present invention, the composition for forming an alignment film that forms an alignment film includes an alignment polymer (A-1) and a compound (A-2) having an active hydrogen reactive group (hereinafter also referred to as "compound (A-2) 2)"). In this specification, "active hydrogen reactive group" refers to a group having active hydrogen such as carboxyl group (-COOH), hydroxyl group (-OH), amine group (-NH ₂ ), mercapto group (-SH), etc. base. If the alignment film is formed of a composition for forming an alignment film containing a compound (A-2) having an active hydrogen reactive group, it is easy to control the adhesion between the substrate and the alignment film, and when the obtained polarizer is bent, the The effect of suppressing peeling that may occur between the base material and the alignment film can be improved.

As the active hydrogen reactive group that the compound (A-2) may have, for example, an epoxy group, a glycidyl group, an azoline group, a carbodiimide group, an aziridinyl group, an imine group, Alkoxysilyl group, isocyanate group, thioisocyanate group, maleic anhydride group, etc. Among them, from the viewpoint of adhesion, compound (A-2) preferably has at least one group selected from the group consisting of alkoxysilyl and isocyanate, more preferably has alkoxysilane base.

The number of active hydrogen reactive groups that the compound (A-2) has is one or more. When there are a plurality of active hydrogen reactive groups, the plurality of active hydrogen reactive groups may be the same or different.

The compound (A-2) preferably further has an active hydrogen-containing group in addition to the active hydrogen reactive group. In this specification, "active hydrogen-containing group" means a functional group containing active hydrogen. If the compound (A-2) has a group containing active hydrogen, it is easy to control the adhesion between the alignment film and the polarizing film, and when the obtained polarizing element is bent, it has an inhibitory effect on the peeling that may occur between the alignment film and the polarizing film can be improved.

The active hydrogen-containing group that the compound (A-2) may have includes, for example, a hydroxyl group, a carboxyl group, an amino group, a mercapto group, a primary amido group, a secondary amido group, and a hydrazine group. Among them, the compound (A-2) preferably has at least one group selected from the group consisting of a hydroxyl group, an amino group, and a mercapto group, and preferably has an amino group or a mercapto group, from the viewpoint of reactivity and adhesiveness.

The number of active hydrogen-containing groups that the compound (A-2) has is one or more. When there are a plurality of active hydrogen-containing groups, the plurality of active hydrogen-containing groups may be the same or different.

In one embodiment of the present invention, the compound (A-2) is a silane coupling agent. When a silane coupling agent is used as the compound (A-2), it is easy to control the adhesiveness with a base material or a polarizing film, and it is easy to obtain a polarizing element excellent in bending resistance. A silane coupling agent may be used individually by 1 type, and may use it in combination of 2 or more types.

As a silane coupling agent, the compound well-known in this field can be used. Specifically, for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, N-(2-aminoethyl)- 3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3- Triethoxysilyl-N-(1,3-dimethyl-butylene)propylamine, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethyl Oxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-acryl Oxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-shrink Glyceryloxypropyltriethoxysilane, 3-glycidoxypropyldimethoxymethylsilane, and 3-glycidoxypropylethoxydimethylsilane.

Also, the silane coupling agent may be a silicone oligomer type. As a silicone oligomer-type silane coupling agent, if the silicone oligomer is expressed in the form of a (monomer) oligomer, for example: 3-mercaptopropyltrimethoxysilane-tetramethoxy Silane copolymer, 3-mercaptopropyltrimethoxysilane-tetraethoxysilane copolymer, 3-mercaptopropyltriethoxysilane-tetramethoxysilane copolymer, 3-mercaptopropyltriethoxysilane Silane-tetraethoxysilane copolymer and other mercaptopropyl-containing copolymers; mercaptomethyltrimethoxysilane-tetramethoxysilane copolymer, mercaptomethyltrimethoxysilane-tetraethoxysilane copolymer, Mercaptomethyltriethoxysilane-tetramethoxysilane copolymer, mercaptomethyltriethoxysilane-tetraethoxysilane copolymer and other mercaptomethyl-containing copolymers; 3-glycidyloxypropyl Trimethoxysilane-tetramethoxysilane copolymer, 3-glycidoxypropyltrimethoxysilane-tetraethoxysilane copolymer, 3-glycidoxypropyltriethoxysilane-tetramethyl Oxysilane copolymer, 3-glycidoxypropyltriethoxysilane-tetraethoxysilane copolymer, 3-glycidoxypropylmethyldimethoxysilane-tetramethoxysilane copolymer 3-glycidoxypropylmethyldimethoxysilane-tetraethoxysilane copolymer, 3-glycidoxypropylmethyldiethoxysilane-tetramethoxysilane copolymer, 3-glycidyloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer and other copolymers containing 3-glycidyloxypropyl; 3-methacryloxypropyltrimethoxy Silane-tetramethoxysilane copolymer, 3-methacryloxypropyltrimethoxysilane-tetraethoxysilane copolymer, 3-methacryloxypropyltriethoxysilane-tetraethoxysilane Methoxysilane copolymer, 3-methacryloxypropyltriethoxysilane-tetraethoxysilane copolymer, 3-methacryloxypropylmethyldimethoxysilane-tetraethoxysilane Methoxysilane copolymer, 3-methacryloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer, 3-methacryloxypropylmethyldiethoxysilane - Copolymers containing methacryloxypropyl groups such as tetramethoxysilane copolymer, 3-methacryloxypropyl methyldiethoxysilane-tetraethoxysilane copolymer; 3- Acryloxypropyltrimethoxysilane-tetramethoxysilane copolymer, 3-acryloxypropyltrimethoxysilane-tetraethoxysilane copolymer, 3-acryloxypropyltriethyl Oxysilane-tetramethoxysilane copolymer, 3-acryloxypropyltriethoxysilane-tetraethoxysilane copolymer, 3-acryloxypropylmethyldimethoxysilane- Tetramethoxysilane copolymer, 3-acryloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer, 3-acryloxypropylmethyldiethoxysilane-tetramethoxysilane Oxysilane copolymer, 3-acryloxypropyl methyldiethoxysilane-tetraethoxysilane copolymer and other copolymers containing acryloxypropyl group; vinyltrimethoxysilane-tetramethoxysilane Oxysilane copolymer, vinyltrimethoxysilane-tetraethoxysilane copolymer, vinyltriethoxysilane-tetraethoxysilane Methoxysilane copolymer, vinyltriethoxysilane-tetraethoxysilane copolymer, vinylmethyldimethoxysilane-tetramethoxysilane copolymer, vinylmethyldimethoxysilane - Copolymers containing vinyl groups such as tetraethoxysilane copolymer, vinylmethyldiethoxysilane-tetramethoxysilane copolymer, vinylmethyldiethoxysilane-tetraethoxysilane copolymer, etc. 3-aminopropyltrimethoxysilane-tetramethoxysilane copolymer, 3-aminopropyltrimethoxysilane-tetraethoxysilane copolymer, 3-aminopropyltriethoxysilane Silane-tetramethoxysilane copolymer, 3-aminopropyltriethoxysilane-tetraethoxysilane copolymer, 3-aminopropylmethyldimethoxysilane-tetramethoxysilane copolymer 3-aminopropylmethyldimethoxysilane-tetraethoxysilane copolymer, 3-aminopropylmethyldiethoxysilane-tetramethoxysilane copolymer, 3-aminopropylmethyldiethoxysilane-tetramethoxysilane copolymer, Amino-containing copolymers such as propylmethyldiethoxysilane-tetraethoxysilane copolymer, etc.

In one embodiment of the present invention, the silane coupling agent preferably has a group containing active hydrogen. Specifically, it is more preferable to have at least one functional group selected from the group consisting of amine groups (primary and secondary), hydroxyl and mercapto groups, more preferably to have primary or secondary amine groups, and more preferably A compound containing Si element having at least one functional group and at least one alkoxysilyl group or silanol group. Amino groups (primary and secondary), hydroxyl groups, and mercapto groups are polar. By properly selecting these functional groups, the adhesion between the obtained alignment film and polarizing film can be controlled, and the bending resistance of the polarizing element can be improved. From this point of view, the silane coupling agent is preferably a silane coupling agent having an alkoxysilyl group and at least one of the above functional groups. Furthermore, the above-mentioned functional groups may also have substituents or protecting groups as appropriate to control the reactivity of the silane coupling agent. As an example of a silane coupling agent having a protecting group, the amine-protected type includes: KBE-9103P (ketimine type) and X-12-1172ES (aldimine type) manufactured by Shin-Etsu Chemical Co., Ltd. , as the thiol-protected type, for example: X-12-1056ES.

A commercially available compound can also be used as the compound (A-2). Such commercially available products include, for example, KP321, KP323, KP324, KP326, KP340, KP341, X22-161A, KF6001, KBM-1003, KBE-1003, KBM-303, KBM-402, KBM-403, KBE-402, KBE-403, KBM-1403, KBM-502, KBM-503, KBE-502, KBE-503, KBM-5103, KBM-602, KBM-603, KBM-903, KBE-903, KBE- 9103, KBM-573, KBM-575, KBM-9659, KBE-585, KBM-802, KBM-803, KBE-846, KBE-9007, X-12-1172ES, X-12-1154, KR-519 A silane coupling agent manufactured by Shin-Etsu Chemical Co., Ltd.

Regarding the content of the compound (A-2) in the composition for forming an alignment film, the composition for forming an alignment film can be appropriately determined according to the type of compound (A-2), the type or surface state of the substrate, the composition of the polarizing film, etc. The content of compound (A-2) in the product. In one embodiment of the present invention, the content of the compound (A-2) is preferably not less than 1 part by mass and not more than 30 parts by mass, more preferably not less than 2.5 parts by mass, relative to 100 parts by mass of the alignment polymer (A-1). It is not more than 25 parts by mass, more preferably not less than 5.0 parts by mass, and more preferably not more than 23 parts by mass. If the content of the compound (A-2) is within the above range, it is easy to maintain good optical characteristics, and further improve the bending resistance, even in the case of a small bending diameter, it is also expected to inhibit the alignment film and the substrate and/or Or the effect of peeling off the polarizing film.

The composition for forming an alignment film usually contains a solvent. The solvent is not particularly limited as long as it can dissolve the components contained in the photoalignment film forming composition, for example, water; methanol, ethanol, ethylene glycol, isopropanol, propylene glycol, methyl cellosolve, Alcohol solvents such as butyl cellosolve 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; acetone Ketone solvents such as , methyl ethyl ketone, cyclopentanone, cyclohexanone, methyl amyl ketone and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; toluene and xylene, etc. Aromatic hydrocarbon solvents, nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran and dimethoxyethane; chlorine-substituted hydrocarbon solvents such as chloroform and chlorobenzene, etc. These solvents may be used alone or in combination of two or more.

In the present invention, the composition for forming an alignment film may contain, in addition to the above-mentioned components, arbitrary components within a range in which the properties of the alignment film are not significantly impaired. Such a component may, for example, be a polymer material or a photosensitizer.

The composition for forming an alignment film can be prepared, for example, by making an alignment polymer (A-1) [or an oligomer or a monomer from which the alignment polymer (A-1) can be obtained] and a compound (A-2), Optionally, other components are dissolved in a solvent to prepare, for example, an alignment film as a cured product thereof can be obtained by curing the composition for forming an alignment film according to the method described below.

The thickness of the alignment film is usually in the range of 10 nm to 10000 nm, preferably 10 nm to 2500 nm, more preferably 10 nm to 1000 nm, further preferably 10 nm to 500 nm, especially 20 Above nm and below 250 nm. The thickness of the alignment film can be measured by a laser microscope or a film thickness gauge. Hereinafter, the measurement of the thickness of each layer such as the substrate or the polarizing film constituting the polarizing element is also the same.

＜Substrate＞ As a base material constituting the polarizing element of the present invention, a resin film or the like previously known in the field of optical films can be used. Examples of the resin constituting the base material include polyolefin-based resins such as polyethylene and polypropylene; cyclic olefin-based resins such as norbornene-based polymers; polyethylene terephthalate, polyethylene naphthalate, etc. Polyester resins such as diesters; poly(meth)acrylic resins such as (meth)acrylic acid and polymethyl(meth)acrylate; triacetyl cellulose, diacetyl cellulose, and cellulose acetate propionate, etc. Cellulose ester-based resins; vinyl alcohol-based resins such as polyvinyl alcohol and polyvinyl acetate; polycarbonate-based resins; polystyrene-based resins; polyarylate-based resins; Amide-based resins; polyimide-based resins; polyetherketone-based resins; polyphenylene sulfide-based resins; polyphenylene ether-based resins, and mixtures thereof. Among them, from the viewpoints of improvement of bending resistance, versatility, heat resistance, etc., those selected from vinyl alcohol-based resins, cellulose ester-based resins, cyclic olefin-based resins, and poly(meth)acrylic resins are preferred. At least one of the group formed.

In the present invention, the substrate preferably has a polar group. Here, in this specification, the fact that the substrate has a polar group means that the polar group exists in the substrate before an alignment film is formed on the substrate. As a polar group, a hydroxyl group, a carboxyl group, an amino group etc. are mentioned, for example. Among them, as a material constituting the substrate, or easily introduced to the surface of the substrate by surface modification treatment of the substrate, etc., and having good reactivity with the active hydrogen reactive group possessed by the compound (A-2) From a viewpoint, it is preferable to have at least one kind of polar group selected from the group consisting of a hydroxyl group, a carboxyl group, and an amino group, and it is more preferable to have a hydroxyl group. By having the above-mentioned polar group in the base material before the alignment film is formed, a bond resulting from the reaction of the polar group present in the base material with the active hydrogen reactive group possessed by the compound (A-2) forming the alignment film is generated, The adhesion between the base material and the alignment film is improved, thereby imparting high bending resistance to the obtained polarizing element. Therefore, in one embodiment of the present invention, there may be between the substrate and the alignment film that constitute the polarizing element of the present invention A bond resulting from the reaction of an active hydrogen reactive group (for example, a Si-O bond).

The polar group is preferably present on the surface of the substrate on the side of the laminated alignment film. Such a base material may be, for example, a base material obtained by using a resin having a polar group such as a vinyl alcohol resin or a cellulose resin as a material and forming the base material into a film shape, or a material having a polar group precursor. The base material obtained by modifying the precursor contained in the precursor film into a polar group after the material is formed into a film (precursor film). As the modifying method, for example, plasma treatment, corona treatment, laser treatment, ozone treatment, saponification treatment, or flame treatment performed under vacuum or atmospheric pressure may be mentioned. In addition, it may also be a substrate obtained by attaching a polymer having a polar group to the surface of a substrate containing a material having no polar group or its precursor group, or may be modified by attaching a polymer having a polar group and its precursor group. The substance is the base material obtained by the polar group. Furthermore, after attaching a monomer or polymer having a polar group to the surface of a base material containing a material without a polar group or its precursor, irradiating radiation, plasma, ultraviolet rays, etc. to react, graft polymerization can also be carried out. And obtain the base material. As a method of attaching a polymer or monomer having a polar group or a polar group precursor to the surface of the substrate, for example, a method of applying a solution in which the polymer or monomer is dissolved to the surface of the substrate, etc. .

The thickness of the substrate is preferably from 1 μm to 20 μm, more preferably from 1 μm to 10 μm, from the viewpoint of processability and thinning of the polarizing element.

＜Polarizing Film＞ In the present invention, the polarizing film is a film (layer) having a polarizing function. From the viewpoint of achieving ultra-thinness and ensuring bending resistance suitable for flexible display materials, in the polarizing element of the present invention, the polarizing film is preferably a coating layer, and more preferably contains a polymerizable liquid crystal compound (B-1), the compound (B-2) having an active hydrogen reactive group, and the polarizing film-forming composition of the dichroic dye (B-3) are cured polarizing film.

The polymerizable liquid crystal compound (B-1) contained in the composition for forming a polarizing film is a compound having at least one polymerizable group. Here, 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 possessed by the polymerizable liquid crystal compound (B-1) include vinyl, vinyloxy, 1-chlorovinyl, isopropenyl, 4-vinylphenyl, (methyl ) acryl group, oxiranyl group, oxetanyl group, etc. Among them, a radical polymerizable group is preferable, a (meth)acryl group, a vinyl group, and a vinyloxy group are more preferable, and a (meth)acryl group is still more preferable. If the polymerizable liquid crystal compound forming the polarizing film has the same functional group (polymerizable group) as that of the compound forming the alignment film, such as (meth)acryl group, the affinity between the alignment film and the polarizing film When the ratio becomes higher, excellent bending resistance can be imparted to the obtained polarizing element.

In the present invention, the polymerizable liquid crystal compound (B-1) is preferably a liquid crystal compound exhibiting smectic liquid crystallinity. By using a polymerizable liquid crystal compound exhibiting smectic liquid crystallinity, a polarizing film with a high degree of alignment order can be formed. The liquid crystal state exhibited by the polymerizable liquid crystal compound (B-1) is more preferably a higher order smectic phase (higher order smectic liquid crystal state) from the viewpoint of realizing a higher degree of alignment order. Here, the higher-order smectic phase means smectic B phase, smectic D phase, smectic E phase, smectic F phase, smectic G phase, smectic H phase, smectic Among the I phase, the smectic J phase, the smectic K phase, and the smectic L phase, the smectic B phase, the smectic F phase, and the smectic I phase are more preferable. Liquid crystallinity may be thermotropic liquid crystal or lyotropic liquid crystal, and thermotropic liquid crystal is preferable in terms of being able to control the dense film thickness. In addition, the polymerizable liquid crystal compound (B-1) may be a monomer, an oligomer obtained by polymerizing a polymerizable group, or a polymer.

The polymerizable liquid crystal compound (B-1) is not particularly limited as long as it is a liquid crystal compound having at least one polymerizable group, and known polymerizable liquid crystal compounds can be used. As a polymeric liquid crystal compound, the compound represented by following formula (B1) is mentioned, for example (Hereinafter, it may be called "a polymeric liquid crystal compound (B1)"). U ¹ -V ¹ -W ¹ -(X ¹ -Y ¹ ) _n -X ² -W ² -V ² -U ² (B1) [In formula (B1), X ¹ and X ² independently represent divalent An aromatic group or a divalent alicyclic hydrocarbon group. Here, the hydrogen atom contained in the divalent aromatic group or a divalent alicyclic hydrocarbon group can be replaced by a halogen atom, an alkyl group with 1 to 4 carbon atoms, or an alkyl group with 1 carbon number. ～4 fluoroalkyl groups, alkoxy groups having 1～4 carbons, cyano groups or nitro groups, the carbon atoms constituting the divalent aromatic groups or divalent alicyclic hydrocarbon groups can be replaced by oxygen atoms, sulfur atoms or nitrogen atomic substitution. Among them, at least ^one of X1 and X2 is a 1,4 ^- phenylene group which may have a substituent or a cyclohexane-1,4-diyl group which may have a substituent. Y ¹ is a single bond or a divalent linking group. n is 1 to 3, and when n is 2 or more, a plurality of X ¹ may be the same as or different from each other. X ² may be the same as or different from at least one or all of the plurality of X ^1s . Moreover, when n is 2 or more, a plurality of Y ¹ may mutually be the same or different. From the viewpoint of liquid crystallinity, n is preferably 2 or more. U ¹ represents a hydrogen atom or a polymerizable group. U ² represents a polymerizable group. W ¹ and W ² are independently a single bond or a divalent linking group. V ¹ and V ² independently represent an alkanediyl group having 1 to 20 carbon atoms which may have a substituent, and -CH ₂ - constituting the alkanediyl group may be replaced by -O-, -CO-, -S- or NH- replace]

In the polymerizable liquid crystal ^compound (B1), X1 and X2 are preferably 1,4 ^- phenylene groups which may have substituents or cyclohexane-1,4-diyl groups which may have substituents independently of each other. , at least one of X ¹ and X ² is a 1,4-phenylene group that may have a substituent, or a cyclohexane-1,4-diyl group that may have a substituent, preferably trans-cyclohexane Alkane-1,4-diyl. Examples of substituents that may be optionally substituted for 1,4-phenylene or cyclohexane-1,4-diyl that may have substituents include methyl, ethyl, and butyl, etc. C1-C4 alkyl group, cyano group, chlorine atom, fluorine atom and other halogen atoms. Preferably it is unsubstituted.

Also, the polymerizable liquid crystal compound (B-1) is preferably the part represented by the formula (B1') in the formula (B1) [hereinafter also referred to as Partial structure (B1')] is an asymmetric structure: -(X ¹ -Y ¹ ) _n -X ² - (B1') [wherein, X ¹ , Y ¹ , X ² and n represent the same meanings as above] . As the polymerizable liquid crystal compound (B1) whose partial structure (B1′) is an asymmetric structure, for example, a polymerizable liquid crystal compound (B1) in which n is 1 and one X ¹ and X ² have different structures. Also, for example: a compound in which n is 2 and the structures of the two ^Y1s are the same as each other, the structure of the two X1s is the same as that of the two X1s, and the polymerizability ^of the structure of ^one X2 is different from the structures of the ^two X1s. Liquid crystal compound (B1) ^{; a} polymerizable liquid crystal compound in which the structure ^of X1 bonded to W1 among ^{two X1s} is different from that ^of the other X1 and X2, and the structures ^of the other X1 and X2 are identical to each other (B1). Further examples include: a compound in which n is 3 and three ^Y1 structures are identical to each other; a polymerizable liquid crystal compound in which at least one of the ^three X1 and ^one X2 structures is different from the other three structures ( B1).

Y ¹ is preferably -CH ₂ CH ₂ -, -CH ₂ O-, -CH ₂ CH ₂ O-, -COO-, -OCOO-, single bond, -N=N-, -CR ^a =CR ^b - , -C≡C-, -CR ^a =N- or -CO-NR ^a -. R ^a and R ^b independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Y ¹ is more preferably -CH ₂ CH ₂ -, -COO- or a single bond, and when there are multiple Y ^1s , the Y ¹ bonded to X ² is more preferably -CH ₂ CH ₂ - or CH ₂ O -. When the structures of X ¹ and X ² are completely the same, it is preferable that two or more Y ¹ having different bonding methods exist. When there are a plurality of Y ¹ having different bonding methods, since the plurality of Y ¹ have an asymmetric structure, smectic liquid crystallinity tends to be easily expressed.

U ² is a polymeric group. U ¹ is a hydrogen atom or a polymerizable group, preferably a polymerizable group. Both U ¹ and U ² are preferably polymerizable groups, more preferably both are radical polymerizable groups. As a polymeric group, what was mentioned above as a polymeric group which a polymeric liquid crystal compound (B-1) has is the same thing as an example. ^The polymerizable group represented by ^U1 and the polymerizable group represented by U2 may be different from each other, but are preferably the same type of group, preferably at least ^one of U1 and U2 is a ⁽ meth)acryl group , more preferably both are (meth)acryloyl. In addition, the polymerizable group may be in a polymerized state or may be in a non-polymerized state, and is preferably in a non-polymerized state.

Examples of the alkanediyl groups represented by V1 and V2 include methylene, ethylidene, propane ^- 1,3 ^- diyl, butane-1,3-diyl, butane-1,4 -diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, decane-1,10 -diyl, tetradecane-1,14-diyl, eicosane-1,20-diyl, etc. V ¹ and V ² are preferably an alkanediyl group having 2 to 12 carbons, more preferably an alkanediyl group having 6 to 12 carbons.

The optional substituent of the alkanediyl group may, for example, be a cyano group or a halogen atom. The alkanediyl group is preferably unsubstituted, more preferably an unsubstituted linear alkanediyl group.

W ¹ and W ² are each independently preferably a single bond, -O-, -S-, -COO- or -OCOO-, more preferably a single bond or -O-.

As a structure that is likely to exhibit smectic liquid crystallinity, it is preferable to have an asymmetric molecular structure in the molecular structure. Specifically, the polymerizable liquid crystal compound (B-1) preferably has the following (B-a) to (B-i) The polymerizable liquid crystal compound having a partial structure is more preferably a polymerizable liquid crystal compound exhibiting smectic liquid crystallinity. From the viewpoint of easy expression of higher-order smectic liquid crystallinity, it is more preferable to have a partial structure of (B-a), (B-b) or (B-c). In addition, in following (B-a)-(B-i), * represents a bond (single bond).

[chemical 6]

As a polymerizable liquid crystal compound (B-1), specifically, the compound represented by a formula (B1-1) - a formula (B1-25) is mentioned, for example. When the polymerizable liquid crystal compound (B-1) has a cyclohexane-1,4-diyl group, the cyclohexane-1,4-diyl group is preferably a trans form.

[chemical 7]

[chemical 8]

[chemical 9]

Among them, preferably selected from formula (B1-2), formula (B1-3), formula (B1-4), formula (B1-5), formula (B1-6), formula (B1-7 ), formula (B1-8), formula (B1-13), formula (B1-14), formula (B1-15), formula (B1-16) and formula (B1-17) At least one of the group. As the polymerizable liquid crystal compound (B-1), one type may be used alone, or two or more types may be used in combination.

The polymerizable liquid crystal compound (B-1) can be produced, for example, by a known method described in Lub et al., Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996), or Japanese Patent No. 4719156 .

In the present invention, the composition for forming a polarizing film may also contain other polymerizable liquid crystal compounds other than the polymerizable liquid crystal compound (B1). From the viewpoint of obtaining a polarizing film with a high degree of alignment order, the composition for forming a polarizing film The ratio of the polymerizable liquid crystal compound (B1) contained in the product to the total mass of the total polymerizable liquid crystal compounds is preferably at least 51% by mass, more preferably at least 70% by mass, and still more preferably at least 90% by mass.

When the composition for forming a polarizing film contains two or more polymerizable liquid crystal compounds, at least one of them may be the polymerizable liquid crystal compound (B1), or all of them may be the polymerizable liquid crystal compound (B1). By combining a plurality of polymerizable liquid crystal compounds, it is sometimes possible to temporarily maintain liquid crystallinity at a temperature below the liquid crystal-crystal phase transition temperature.

The content of the polymerizable liquid crystal compound (B-1) in the composition for forming a polarizing film is preferably 40 to 99.9% by mass, more preferably 60 to 99% by mass, based on the solid content of the composition for forming a polarizing film, More preferably, it is 70-99 mass %. There exists a tendency for the alignment property of a polymeric liquid crystal compound to become high that content of a polymeric liquid crystal compound (B-1) is in the said range. Furthermore, the solid content of the composition for forming a polarizing film refers to the total amount of components obtained by removing volatile components such as solvents from the composition for forming a polarizing film, and is hereinafter referred to as "solid content" in this specification. In the same case, it refers to the component obtained by removing volatile components such as solvents from the target composition.

In the present invention, the composition for forming a polarizing film preferably contains a compound (B-2) having an active hydrogen reactive group (hereinafter also referred to as "compound (B-2)"). The active hydrogen reactive group possessed by the compound (B-2) may, for example, be the same as those exemplified as the active hydrogen reactive group which may be possessed by the compound (A-2) contained in the composition for forming an alignment film. The functional group. Among them, from the viewpoint of reactivity with active hydrogen-containing groups that compound (A-2) may have, compound (B-2) preferably has And at least one group of the group consisting of an alkoxysilyl group, more preferably has an isocyanato group or an alkoxysilyl group, and still more preferably has an isocyanato group.

The number of active hydrogen reactive groups possessed by compound (B-2) is usually 1 to 20, preferably 1 to 10, and in a more preferred embodiment of the present invention, there are at least 2 active hydrogen reactive groups base. When there are a plurality of active hydrogen reactive groups, the plurality of active hydrogen reactive groups may be the same or different.

The compound (B-2) preferably further has a polymerizable group in addition to the active hydrogen reactive group. The polymerizable group may be, for example, a carbon-carbon unsaturated bond such as a carbon-carbon double bond or a carbon-carbon triple bond, and specifically, vinyl, vinyloxy, 1-chlorovinyl, isopropenyl, etc. , 4-vinylphenyl, (meth)acryl, oxiranyl, oxetanyl, etc. Among them, in the relationship with the alignment polymer (A-1), if the compound (B-2) has the same functional group (polymerizable group) as the above-mentioned compound, such as (meth)acryl group, the alignment film The affinity with the polarizing film becomes high, and the bending resistance of the obtained polarizing element can be further improved, so a (meth)acryl group is preferable.

The number of polymerizable groups that the compound (B-2) has is usually 1-20, preferably 1-10.

In one embodiment of the present invention, the compound (B-2) preferably has at least one group selected from the group consisting of epoxy group, glycidyl group, isocyanate group and alkoxysilyl group as a reactive group. The hydrogen-reactive group preferably includes a (meth)acryl group as a polymerizable group, and more preferably has one or more isocyanate groups and one or more (meth)acryl groups.

Specific examples of the compound (B-2) include: compounds having a (meth)acryl group and an epoxy group such as methacryloxyglycidyl ether or acryloxyglycidyl ether; oxa Cyclobutane acrylate or oxetane methacrylate and other compounds with (meth)acryl and oxetanyl groups; lactone acrylate or lactone methacrylate and other compounds with (meth) Compounds with acryl and lactone groups; compounds with vinyl and oxazolyl groups such as vinyl oxazoline or isopropenyl oxazoline; isocyanatomethyl acrylate and isocyanatomethyl methacrylate , 2-isocyanatoethyl acrylate and 2-isocyanatoethyl methacrylate and other compounds with (meth)acryl and isocyanate groups; 3-acryloxypropyltrimethoxy Silane, 3-methacryloxypropylmethyldimethoxysilane, oligomers of compounds having (meth)acryl and alkoxysilyl groups, etc. Moreover, the compound etc. which have a vinyl group, a vinylidene group, and an acid anhydride, such as methacrylic anhydride, acrylic anhydride, maleic anhydride, and vinylmaleic anhydride, are mentioned. Among them, preferred are methacryloxy glycidyl ether, acryloxy glycidyl ether, isocyanatomethyl acrylate, isocyanatomethyl methacrylate, vinyloxazoline, acrylic acid 2- Isocyanatoethyl ester, 2-isocyanatoethyl methacrylate, 3-acryloxypropyltrimethoxysilane and the above oligomers, especially isocyanatomethyl acrylate, acrylic acid 2-isocyanatoethyl ester, 3-acryloxypropyltrimethoxysilane and the above oligomers.

A commercial item can also be used as a compound (B-2). Such commercially available products include, for example, Laromer (registered trademark) PR9000 (manufactured by BASF Corporation), Karenz AOI (registered trademark) (manufactured by Showa Denko Co., Ltd.), Karenz BEI (registered trademark) (manufactured by Showa Denko Co., Ltd. company), Karenz MOI-EG (registered trademark) (manufactured by Showa Denko Co., Ltd.), KBM-5103 (manufactured by Shin-Etsu Chemical Co., Ltd.), etc.

When the composition for forming a polarizing film contains the compound (B-2), the compound (B-2) may be the same as or different from the compound (A-2) contained in the composition for forming an alignment film.

The content of the compound (B-2) in the composition for forming a polarizing film is preferably from 0.1 to 12 parts by mass, more preferably from 0.5 to 10 parts by mass, based on 100 parts by mass of the polymerizable liquid crystal compound (B-1). It is at most one part by mass, and more preferably at least 1 part by mass and at most 10 parts by mass. When the content of the compound (B-2) is within the above range, it is easy to improve the bending resistance of the polarizing element without impairing the alignment of the obtained polarizing film. Compound (B-2) may be used alone or in combination of two or more. In the case of using two or more compounds (B-2), it is preferable that the total content thereof is within the above-mentioned range.

In this invention, the composition for polarizing film formation contains a dichroic dye (B-3) normally. Here, the dichroic dye means a dye having a property that the absorbance of the molecule in the long-axis direction is different from the absorbance in the short-axis direction. In the present invention, the usable dichroic dye (B-3) is not particularly limited as long as it has the above properties, and may be a dye or a pigment. In addition, two or more dyes or pigments may be used in combination, respectively, or a dye and a pigment may be used in combination. In addition, the dichroic dye may have polymerizability or liquid crystallinity.

The dichroic dye (B-3) preferably has a maximum absorption wavelength (λ _MAX ) in the range of 300 to 700 nm. As such a dichroic dye, an acridine dye, a cyanine dye, a cyanine dye, a naphthalene dye, an azo dye, an anthraquinone dye, etc. are mentioned, for example.

As an azo dye, for example: a monoazo dye, a disazo dye, a trisazo dye, a tetrazo dye, a stilbene azo dye, etc., preferably a disazo dye and a trisazo dye, for example, For example: a compound represented by formula (I) (hereinafter also referred to as "compound (I)"). K ¹ (-N=NK ² ) _p -N=NK ³ (I) [In the formula (I), K ¹ and K ³ each independently represent a phenyl group which may have a substituent, a naphthyl group which may have a substituent, A phenylbenzoate group which may have a substituent or a valent heterocyclic group which may have a substituent. K2 represents a ^p -phenylene group that may have a substituent, a naphthalene-1,4-diyl group that may have a substituent, a 4,4'-stilbene group that may have a substituent, or a divalent heterocyclic ring that may have a substituent base. p represents an integer of 0-4. When p is an integer of 2 or more, the plurality of K ² may be the same as or different from each other. In the range of visible light absorption, -N=N-bonds can be replaced by -C=C-, -COO-, -NHCO-, -N=CH-bonds]

Examples of monovalent heterocyclic groups include those obtained by removing one hydrogen atom from heterocyclic compounds such as quinoline, thiazole, benzothiazole, thienothiazole, imidazole, benzimidazole, oxazole, and benzoxazole. base. The divalent heterocyclic group may, for example, be a group obtained by removing two hydrogen atoms from the above heterocyclic compound.

As phenyl, naphthyl, benzoate phenyl group and monovalent heterocyclic group in K ¹ and K ³ , and p-phenylene, naphthalene-1,4-diyl, 4,4'- in K ² The optional substituents of the stilbene group and the divalent heterocyclic group include, for example, an alkyl group having 1 to 20 carbon atoms, an alkyl group having a polymerizable group having 1 to 20 carbon atoms, and an alkene group having 1 to 4 carbon atoms. Alkoxy groups with 1 to 20 carbons such as methoxy, ethoxy and butoxy; alkoxy groups with 1 to 20 carbons having a polymerizable group; trifluoromethyl groups with 1 to 4 carbons Fluorinated alkyl group; cyano group; nitro group; halogen atom; amino group, diethylamino group, pyrrolidinyl group, etc. Amino group of 1-6 alkyl group, amine group of 1-6 carbon number containing 1 or 2 polymerizable groups, or 2-substituted alkyl group bonded together to form an alkane group of 2-8 carbon number Diyl amino group. The unsubstituted amino group is -NH ₂ ) and the like. In addition, as said polymeric group, a (meth)acryl group, a (meth)acryloxy group, etc. are mentioned.

[式(I-1)～(I-8)中， B ¹～B ³⁰相互獨立地表示氫原子、碳數1～6之烷基、碳數1～6之烯基、碳數1～4之烷氧基、氰基、硝基、經取代或未經取代之胺基(經取代之胺基及未經取代之胺基之定義如上所述)、氯原子或三氟甲基。 n1～n4分別獨立地表示0～3之整數。 於n1為2以上之情形時，複數個B ²相互可相同，亦可不同， 於n2為2以上之情形時，複數個B ⁶相互可相同，亦可不同， 於n3為2以上之情形時，複數個B ⁹相互可相同，亦可不同， 於n4為2以上之情形時，複數個B ¹⁴相互可相同，亦可不同] Among the compounds (I), preferred are compounds represented by any one of the following formulas (I-1) to (I-8). [chemical 10]

[In the formulas (I-1) to (I-8), B ¹ to B ³⁰ independently represent a hydrogen atom, an alkyl group with 1 to 6 carbons, an alkenyl group with 1 to 6 carbons, an alkenyl group with 1 to 4 carbons alkoxy, cyano, nitro, substituted or unsubstituted amino (the definitions of substituted and unsubstituted amino are as above), chlorine atom or trifluoromethyl. n1-n4 each independently represent the integer of 0-3. When n1 is 2 or more, a plurality of B ² may be the same or different from each other. When n2 is 2 or more, a plurality of B ⁶ may be the same or different. When n3 is 2 or more , the plurality of B ⁹ may be the same or different, and when n4 is 2 or more, the plurality of B ¹⁴ may be the same or different]

[式(I-9)中， R ¹～R ⁸相互獨立地表示氫原子、-R ^x、-NH ₂、-NHR ^x、-NR ^x ₂、-SR ^x或鹵素原子。 R ^x表示碳數1～4之烷基或碳數6～12之芳基] The above-mentioned anthraquinone dye is preferably a compound represented by formula (I-9). [chemical 11]

[In formula (I-9), R ¹ to R ⁸ independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom. R ^x represents an alkyl group with 1 to 4 carbons or an aryl group with 6 to 12 carbons]

[式(I-10)中， R ⁹～R ¹⁵相互獨立地表示氫原子、-R ^x、-NH ₂、-NHR ^x、-NR ^x ₂、-SR ^x或鹵素原子。 R ^x表示碳數1～4之烷基或碳數6～12之芳基] As the above-mentioned ketone dye, a compound represented by the formula (I-10) is preferable. [chemical 12]

[In the formula (I-10), R ⁹ to R ¹⁵ independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom. R ^x represents an alkyl group with 1 to 4 carbons or an aryl group with 6 to 12 carbons]

[式(I-11)中， R ¹⁶～R ²³相互獨立地表示氫原子、-R ^x、-NH ₂、-NHR ^x、-NR ^x ₂、-SR ^x或鹵素原子。 R ^x表示碳數1～4之烷基或碳數6～12之芳基] 於式(I-9)、式(I-10)及式(I-11)中，作為R ^x之碳數1～6之烷基，可例舉：甲基、乙基、丙基、丁基、戊基及己基等，作為碳數6～12之芳基，可例舉：苯基、甲苯甲醯基、二甲苯基及萘基等。 The acridine dye is preferably a compound represented by formula (I-11). [chemical 13]

[In formula (I-11), R ¹⁶ to R ²³ independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom. R ^x represents an alkyl group with 1 to 4 carbons or an aryl group with 6 to 12 carbons] In formula (I-9), formula (I-10) and formula (I-11), as the carbon number of R ^x Alkyl groups of 1 to 6 include methyl, ethyl, propyl, butyl, pentyl, and hexyl, and aryl groups with 6 to 12 carbons include phenyl and toluyl , xylyl and naphthyl, etc.

[式(I-12)中， D ¹及D ²分別獨立地表示式(I-12a)～式(I-12d)之任一者所表示之基。 [化15]

n5表示1～3之整數] [化16]

[式(I-13)中， D ³及D ⁴分別獨立地表示式(I-13a)～式(1-13h)之任一者所表示之基。 [化17]

n6表示1～3之整數] As the above-mentioned cyanine dye, compounds represented by formula (I-12) and compounds represented by formula (I-13) are preferable. [chemical 14]

[In formula (I-12), D ¹ and D ² each independently represent a group represented by any one of formula (I-12a) to formula (I-12d). [chemical 15]

n5 represents an integer of 1 to 3] [Chemical 16]

[In formula (I-13), D ³ and D ⁴ each independently represent a group represented by any one of formula (I-13a) to formula (1-13h). [chemical 17]

n6 represents an integer from 1 to 3]

Among these dichroic dyes, azo dyes are better used in the production of polarizing films with excellent polarizing performance due to their high linearity. Therefore, in one embodiment of the present invention, the dichroic dye (B-3) contained in the composition for forming a polarizing film that forms a polarizing film is preferably an azo dye.

In the present invention, the weight average molecular weight of the dichroic dye (B-3) is usually 300-2000, preferably 400-1000.

In one Embodiment of this invention, it is preferable that the dichroic dye (B-3) contained in the composition for polarizing film formation which forms a polarizing film is hydrophobic. If the dichroic dye (B-3) is hydrophobic, the compatibility of the dichroic dye (B-3) and the polymerizable liquid crystal compound (B-1) is improved, and the dichroic dye (B-3) and The polymerizable liquid crystal compound (B-1) forms a uniform phase state, and can obtain a polarizing film with a high degree of alignment order. In addition, in this invention, a hydrophobic dichroic dye means the dye whose solubility with respect to 100 g of water at 25 degreeC is 1 g or less.

Regarding the content of the dichroic dye (B-3) in the composition for forming a polarizing film, the dichroic dye (B-3) in the composition for forming a polarizing film can be appropriately determined according to the type of the dichroic dye used, etc. -3) The content of the dichroic dye (B-3) in the composition for forming a polarizing film is preferably 0.1 to 50 parts by mass, more preferably 0.1 to 20 parts by mass relative to 100 parts by mass of the polymerizable liquid crystal compound parts, more preferably 0.1 to 12 parts by mass. If the content of the dichroic dye (B-3) is within the above range, it is difficult to interfere with the alignment of the polymerizable liquid crystal compound, and a polarizing film with a higher degree of alignment order can be obtained.

In this invention, the composition for polarizing film formation used for forming a polarizing film may contain a polymerization initiator. The polymerization initiator is a compound that can start the polymerization reaction of the polymerizable liquid crystal compound (B-1), and is preferably a photopolymerization initiator at the point that the polymerization reaction can be started at a lower temperature. Specifically, a photopolymerization initiator capable of generating active radicals or acids by the action of light is exemplified, and among them, a photopolymerization initiator that generates free radicals by the action of light is preferable. A polymerization initiator can be used individually or in combination of 2 or more types.

系化合物、鹵代苯乙酮系化合物、二烷氧基苯乙酮系化合物、鹵代雙咪唑系化合物、鹵代三𠯤系化合物、三𠯤系化合物等。 As the photopolymerization initiator, known photopolymerization initiators can be used, for example, as photopolymerization initiators that generate active radicals, there are self-cleavage type photopolymerization initiators and hydrogen abstraction type photopolymerization initiators. As the self-cleavage type photopolymerization initiator, self-cleavage type benzoin-based compounds, acetophenone-based compounds, hydroxyacetophenone-based compounds, α-aminoacetophenone-based compounds, oxime ester-based compounds, acyl oxidation Phosphine compounds, azo compounds, etc. Moreover, as a hydrogen abstraction type photopolymerization initiator, a hydrogen abstraction type benzophenone type compound, a benzoin ether type compound, a benzoyl ketal type compound, a dibenzocycloheptanone type compound, an anthraquinone type compound, etc. can be used. , 𠮿 ketone compounds, 9-oxosulfur

series compounds, halogenated acetophenone series compounds, dialkoxyacetophenone series compounds, halogenated bis-imidazole series compounds, halogenated three-series compounds, three-series compounds, etc.

As the acid-generating photopolymerization initiator, iodonium salts, permeic acid salts, and the like can be used.

Among them, from the viewpoint of preventing the dissolution of the pigment, it is preferable to react at low temperature, and from the viewpoint of the reaction effect at low temperature, a self-cleavage type photopolymerization initiator is preferable, and an acetophenone-based compound is particularly preferable. , Hydroxyacetophenone-based compounds, α-aminoacetophenone-based compounds, oxime ester-based compounds.

As a photoinitiator, specifically, the following are mentioned, for example. Benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin isobutyl ether and other benzoin compounds; 2-Hydroxy-2-methyl-1-phenylpropan-1-one, 1,2-diphenyl-2,2-dimethoxyethan-1-one, 2-hydroxy-2-methyl -1-[4-(2-hydroxyethoxy)phenyl]propane-1-one, 1-hydroxycyclohexyl phenyl ketone and 2-hydroxy-2-methyl-1-[4-(1-methyl Hydroxyacetophenone compounds such as oligomers of vinyl)phenyl]propan-1-one; 2-methyl-2-𠰌linyl-1-(4-methylphenylthio)propan-1-one, 2-dimethylamino-2-benzyl-1-(4-𠰌linylphenyl ) butane-1-one and other α-aminoacetophenone compounds; 1,2-octanedione, 1-[4-(phenylthio)-,2-(O-benzoyl oxime)], ethyl ketone, 1-[9-ethyl-6-(2-methyl Oxime ester compounds such as benzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyl oxime); Acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide; Benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 3,3',4,4' - Benzophenone compounds such as tetrakis(tert-butylcarbonylperoxy)benzophenone and 2,4,6-trimethylbenzophenone; Dialkoxyacetophenone compounds such as diethoxyacetophenone; 2,4-bis(trichloromethyl)-6-(4-methoxyphenyl)-1,3,5-trichloromethyl, 2,4-bis(trichloromethyl)-6-(4- Methoxynaphthyl)-1,3,5-trimethoxyl, 2,4-bis(trichloromethyl)-6-(4-methoxystyryl)-1,3,5-trimethoxyl, 2,4-bis(trichloromethyl)-6-[2-(5-methylfuran-2-yl)ethenyl]-1,3,5-trimethanone, 2,4-bis(trichloromethyl Base)-6-[2-(furan-2-yl)ethenyl]-1,3,5-three 𠯤, 2,4-bis(trichloromethyl)-6-[2-(4-diethyl Amino-2-methylphenyl)vinyl]-1,3,5-trimethoxy and 2,4-bis(trichloromethyl)-6-[2-(3,4-dimethoxy Phenyl)vinyl]-1,3,5-trisalpine and other trisylvanic compounds. Regarding the photopolymerization initiator, for example, in relation to the polymerizable liquid crystal compound (B-1) or compound (B-2) contained in the composition for forming a polarizing film, it can be suitably selected from the photopolymerization initiators mentioned above. choose.

Moreover, a commercially available photopolymerization initiator can also be used. Examples of commercially available polymerization initiators include: Irgacure (registered trademark) 907, 184, 651, 819, 250, and 369, 379, 127, 754, OXE01, OXE02, OXE03 (manufactured by BASF); Omnirad BCIM , Esacure 1001M, Esacure KIP160 (manufactured by IDM Resins B.V.); Seikuol (registered trademark) BZ, Z, and BEE (manufactured by Seiko Chemical Co., Ltd.); kayacure (registered trademark) BP100, and UVI-6992 (Dow Chemical Co., Ltd. company); Adeka Optomer SP-152, N-1717, N-1919, SP-170, Adeka Arkles NCI-831, Adeka Arkles NCI-930 (manufactured by ADEKA Co., Ltd.); TAZ-A, and TAZ-PP ( Nihon SiberHegner Co., Ltd.); and TAZ-104 (Sanwa Chemical Co., Ltd.) and the like.

The content of the polymerization initiator in the composition for forming a polarizing film for forming a polarizing film is preferably 1 to 10 parts by mass, more preferably 1 to 8 parts by mass, based on 100 parts by mass of the polymerizable liquid crystal compound (B-1). Parts by mass, more preferably 2 to 8 parts by mass, particularly preferably 4 to 8 parts by mass. If the content of the polymerization initiator is within the above range, the polymerization reaction of the polymerizable liquid crystal compound can proceed without greatly disturbing the alignment of the polymerizable liquid crystal compound.

等𠮿酮化合物(例如，2,4-二乙基9-氧硫

、2-異丙基9-氧硫

等)；蒽、烷氧基含有蒽(例如二丁氧基蒽等)等蒽化合物；啡噻𠯤及紅螢烯等。光敏劑可單獨使用或組合兩種以上使用。The composition for polarizing film formation may further contain a photosensitizer. By using a photosensitizer, the polymerization reaction of the polymerizable liquid crystal compound (B-1) can be further accelerated. Examples of photosensitizers include: ketone, 9-oxosulfur

Other ketone compounds (for example, 2,4-diethyl 9-oxosulfur

, 2-isopropyl 9-oxosulfur

etc.); anthracene compounds such as anthracene and alkoxy containing anthracene (such as dibutoxyanthracene, etc.); A photosensitizer can be used individually or in combination of 2 or more types.

When the composition for forming a polarizing film contains a photosensitizer, the content of the photosensitizer can be appropriately determined according to the type and amount of the polymerization initiator and the polymerizable liquid crystal compound (B-1). The content of the agent is preferably from 0.1 to 30 parts by mass, more preferably from 0.5 to 10 parts by mass, and still more preferably from 0.5 to 8 parts by mass, based on 100 parts by mass of the polymerizable liquid crystal compound (B-1).

Moreover, the composition for polarizing film formation may contain a leveling agent. The leveling agent has the function of adjusting the fluidity of the composition for forming a polarizing film and making the coating film obtained by applying the composition for forming a polarizing film more flat. active agent. The leveling agent is preferably at least one selected from the group consisting of a polyacrylate compound as a main component and a fluorine atom-containing compound as a main component. A leveling agent can be used individually or in combination of 2 or more types.

Examples of leveling agents mainly composed of polyacrylate compounds include "BYK-350", "BYK-352", "BYK-353", "BYK-354", "BYK-355", " BYK-358N", "BYK-361N", "BYK-380", "BYK-381" and "BYK-392" (BYK Chemie).

As a leveler mainly composed of a compound containing a fluorine atom, for example, "Megafac (registered trademark) R-08", "Megafac R-30", "Megafac R-90", "Megafac F-410 ", "Megafac F-411", "Megafac F-443", "Megafac F-445", "Megafac F-470", "Megafac F-471", "Megafac F-477", "Megafac F-479" , "Megafac F-482" and "Megafac F-483" (DIC Corporation); 393", "Surflon SC-101", "Surflon SC-105", "KH-40" and "SA-100" (AGC Seimi Chemical Co., Ltd.); "E1830", "E5844" (Daikin Fine Chemical Research Co., Ltd.); "Eftop EF301", "Eftop EF303", "Eftop EF351" and "Eftop EF352" (Mitsubishi Materials Electron Chemicals Co., Ltd.).

When the composition for forming a polarizing film contains a leveling agent, the content of the leveling agent is preferably 0.05 to 5 parts by mass, more preferably 0.05 to 3 parts by mass relative to 100 parts by mass of the polymerizable liquid crystal compound (B-1). share. When the content of the leveling agent is within the above range, it is easy to align the polymerizable liquid crystal compound (B-1), and unevenness is less likely to occur, and a smoother polarizing film tends to be obtained.

The composition for polarizing film formation may contain other additives other than a photosensitizer and a leveling agent. Examples of other additives include coloring agents such as antioxidants, release agents, stabilizers, and bluing agents, flame retardants, lubricants, and the like. When the composition for forming a polarizing film contains other additives, the content of the other additives is preferably more than 0% and 20% by mass or less, more preferably more than 0% and less than the solid content of the composition for forming a polarizing film. 10% by mass or less.

The composition for forming a polarizing film can be produced by a previously known method for preparing a composition for forming a polarizing film, for example, by mixing a polymerizable liquid crystal compound (B-1), a compound (B-2) and a dichroic dye (B-3), and if necessary, a polymerization initiator and the above-mentioned additives are mixed and stirred to prepare. In addition, since the viscosity of the compound exhibiting smectic liquid crystallinity is generally high, from the viewpoint of improving the coatability of the composition for forming a polarizing film and making it easy to form a polarizing film, it can be added to the composition for forming a polarizing film. The viscosity is adjusted by adding a solvent.

The solvent used in the composition for forming a polarizing film can be appropriately selected according to the solubility of the polymerizable liquid crystal compound (B-1), compound (B-2) and dichroic dye (B-3) to be used, etc. The solvent used in the composition for forming a polarizing film is selected. Specifically, the same ones as those exemplified as the solvent usable in the composition for forming an alignment film can be mentioned at present. As a solvent, only 1 type may be used individually, and 2 or more types may be used in combination. The content of the solvent is preferably from 100 to 1900 parts by mass, more preferably from 150 to 900 parts by mass, and still more preferably from 180 to 600 parts by mass, based on 100 parts by mass of solid content of the composition for forming a polarizing film.

For example, a polarizing film can be obtained by hardening the composition for polarizing film formation by the method mentioned below. For example, the polymerizable liquid crystal compound (B-1) such as the polymerizable liquid crystal compound (B1) can maintain a liquid crystal phase, especially a smectic phase, preferably a liquid crystal state of a higher order smectic phase by photopolymerization In this case, a polarizing film is formed. The polarizing film obtained by polymerization under the condition of maintaining the liquid crystal state of the smectic phase has polarizing properties compared with the previous host-guest polarizing film, that is, the polarizing film containing the liquid crystal state of the nematic phase. higher advantage. Furthermore, it also has the advantage that it is more excellent in strength compared with the thing which apply|coats only a dichroic dye or a lyotropic liquid crystal.

In the present invention, the polarizing film is preferably a polarizing element with a high degree of alignment order. Polarizing elements with a high degree of alignment order can obtain Buhlerg peaks from high-order structures such as hexagonal phases or crystals in X-ray diffraction measurements. A Bragg peak means a peak derived from a surface periodic structure of molecular alignment. Therefore, it is preferable that the polarizing film constituting the polarizing element of the present invention exhibit a Buhlerg peak in X-ray diffraction measurement. That is, in the polarizing film constituting the polarizing element of the present invention, the polymerizable liquid crystal compound (B-1) or its polymer is preferably aligned such that the polarizing film shows a Buhlerg peak in X-ray diffraction measurement, more preferably It is "horizontal alignment" in which the molecules of the polymerizable liquid crystal compound (B-1) are aligned in the direction of light absorption. In the present invention, it is preferably a polarizing element with a surface period interval of molecular alignment of 3.0-6.0 Å. For example, the higher degree of alignment order of the Buhlerg peak can be determined by the types of the polymerizable liquid crystal compound (B-1), compound (B-2) and dichroic dye (B-3) used or their etc., and the type or amount of the polymerization initiator is controlled to achieve.

The thickness of the polarizing film can be appropriately selected according to the display device used, and is preferably 0.1-10 μm, more preferably 0.3-9 μm, and still more preferably 0.5-8 μm. If the film thickness of the polarizing film is more than the above-mentioned lower limit, it is easy to prevent the desired light absorption from being obtained, and if it is below the above-mentioned upper limit, it is easy to suppress the occurrence of alignment defects caused by the reduction of the alignment restriction force of the alignment film. .

In one embodiment of the present invention, the polarizing element may also include an overcoat layer on the surface of the polarizing film opposite to the alignment film. The overcoat layer functions, for example, to prevent diffusion of a dichroic dye or to prevent damage to a polarizing film. The overcoat layer is not particularly limited as long as it can impart the desired function to the polarizing element. Layers formed by sexual components, etc. Among them, since the polarity of the water-soluble polymer is generally different from that of the dichroic dye, the effect of preventing the diffusion of the dichroic dye is excellent, and it can be expected that by combining with the compound contained in the composition for forming a polarizing film ( The active hydrogen reactive groups in B-2) form bonds to improve the bending resistance. Therefore, in one embodiment of the present invention, the outer covering layer is preferably formed of a resin composition containing a water-soluble polymer. Floor.

Examples of water-soluble polymers that can form the outer coating include: polyacrylamide-based polymers; polyvinyl alcohol, ethylene-vinyl alcohol copolymers, (meth)acrylic acid or its anhydride-vinyl alcohol copolymers Such as vinyl alcohol polymers; carboxy vinyl polymers; polyvinylpyrrolidone; starches; sodium alginate; or polyethylene oxide polymers, etc. These polymers may be used alone or in combination of two or more.

When the outer covering layer is a layer formed of a resin composition containing a water-soluble polymer (hereinafter also referred to as "resin composition containing a water-soluble polymer"), the content of the water-soluble polymer in the layer Preferably it is 75 mass % or more, More preferably, it is 80 mass % or more, More preferably, it is 85 mass % or more.

When the overcoat layer is a layer formed of a resin composition containing a water-soluble polymer, a crosslinked structure may also be introduced by using a crosslinking agent in order to increase the density of the layer. As such a cross-linking agent, for example, water-soluble additives or cross-linking agents such as ion-bonding cross-linking agents such as glyoxylate or epoxy-based cross-linking agents, and isocyanate-based cross-linking agents for the purpose of imparting water resistance can be used. Hydrophobic crosslinking agents such as polyaldehyde-based crosslinking agents such as glyoxal or glyoxal derivatives, and metal compound-based crosslinking agents such as zirconium chloride or titanium lactate.

When using a crosslinking agent, the addition amount can be suitably determined according to the kind etc. of the crosslinking agent used. For example, the crosslinking agent can be 0.1-100 mass parts with respect to 100 mass parts of water-soluble polymers, Preferably it is 1-50 mass parts, More preferably, it is 10-30 mass parts. When the content of the crosslinking agent is within the above range, the overcoat layer becomes dense, and the shielding effect of the dichroic dye (B-3) in the polarizing film is easily enhanced.

The resin composition containing a water-soluble polymer capable of forming an overcoat layer can generally be prepared as a solution obtained by dissolving a water-soluble polymer in a solvent. The solvent can be selected according to the water-soluble polymer to be used, and typically, water, alcohol, a mixture of water and alcohol, etc. are mentioned, and water is preferred.

The solid content concentration of the water-soluble polymer-containing resin composition obtained by adding a solvent to the components constituting the outer coating layer, such as a water-soluble polymer or a crosslinking agent, is preferably 1 to 50% by mass, more preferably 2 to 50% by mass. 30% by mass, more preferably 3 to 15% by mass. When the solid content concentration of the water-soluble polymer-containing resin composition is within the above-mentioned range, the viscosity of the composition becomes low, so that the applicability and workability are good.

The water-soluble polymer-containing resin composition may contain other components such as additives in addition to solvents such as water-soluble polymers, crosslinking agents, and water. As such other components, a preservative, a leveling agent, etc. are mentioned, for example. When the water-soluble polymer-containing resin composition contains additives and other components, the amount of the additives and other components is preferably 10% by mass or less, more preferably 5% by mass or less, based on the solid content of the resin composition.

For example, the overcoat layer can be formed by curing a water-soluble polymer-containing resin composition prepared by dissolving essential components such as a water-soluble polymer and a crosslinking agent in a solvent according to the method described below.

The thickness of the overcoat layer can be appropriately selected according to the material constituting the overcoat layer or the display device to be used. The thickness of the overcoat layer may be, for example, 0.1-5.0 μm, preferably 0.5-3.0 μm.

The polarizing element of the present invention can be manufactured by, for example, the following method, which includes the following steps: (1) forming a polarizer comprising an alignment polymer (A-1) and an active hydrogen reactive group on a substrate having a polar group. A coating film of the composition for forming an alignment film of the compound (A-2), and drying the coating film, whereby the active hydrogen reactive group possessed by the compound (A-2) reacts with the polar group possessed by the substrate and form a bond; (2) form an alignment film by performing rubbing treatment or light irradiation on the dry coating film obtained in step (1); (3) form an alignment film containing polymerizable liquid crystal on the alignment film obtained in step (2). a coating film of a composition for forming a polarizing film of the compound (B-1), the compound (B-2) having an active hydrogen reactive group, and the dichroic dye (B-3), and drying the coating film; and ( 4) Harden the polymerizable liquid crystal compound (B-1) and the dichroic pigment (B-3) in the dried coating film obtained in step (3) in an aligned state to form a polarizing film. Hereinafter, this manufacturing method is also called "the manufacturing method of the polarizing element of this invention."

In step (1), as a method of coating the composition for forming an alignment film on a substrate, a spin coating method, an extrusion method, a gravure coating method, a die coating method, a bar coating method, etc. may be mentioned. Known methods such as coating methods such as the cloth method and the dressing method, or printing methods such as the flexographic method.

The solvent in the coating film of the obtained composition for forming an alignment film is dried, and the active hydrogen reactive group possessed by the compound (A-2) reacts with the polar group possessed by the substrate to form The key to the base. Thereby, higher adhesion between the base material and the alignment film can be ensured. The drying method for removing the solvent contained in the coating film of the composition for forming an alignment film may, for example, be natural drying, ventilation drying, heat drying, or reduced pressure drying. Among them, heat drying is preferred from the viewpoint of accelerating the reaction between the active hydrogen reactive group possessed by the compound (A-2) and the polar group possessed by the substrate, or from the viewpoint of productivity. Conditions for heating and drying can be appropriately determined according to the composition of the composition for forming an alignment film, the type of substrate, the thickness of the alignment film, and the like. For example, the heating temperature may be 50-200°C, preferably 100-150°C. Also, the drying time is usually 20 seconds to 10 minutes, preferably 30 seconds to 5 minutes.

When the alignment film is a rubbed alignment film, the rubbed alignment film can be obtained by subjecting the dry coating film of the composition for forming an alignment film obtained in the step (1) to the rubbing treatment in the step (2). As the rubbing treatment method, for example, a method of bringing the dry coating film of the composition for forming an alignment film obtained in the step (1) into contact with a rubbing roll wound with a rubbing cloth and rotating.

When the alignment film is a photo-alignment film, the photo-alignment film can be obtained by irradiating the dry coating film of the composition for forming an alignment film obtained in the step (1) with light in the step (2). By selecting the polarization direction of the irradiated polarized light, the direction of the alignment restriction force can be arbitrarily controlled.

The method of irradiating polarized light may be a method of directly irradiating polarized light on the dry coating film of the composition for forming an alignment film formed on the substrate, or a method of irradiating polarized light from the substrate side and transmitting the polarized light. The polarized light is preferably substantially parallel light. The wavelength of the irradiated polarized light can be the wavelength region where the photoreactive group of the photoalignment polymer can absorb light energy. Specifically, UV (ultraviolet light) having a wavelength of 250 to 400 nm is preferable. The light source used in the polarized light irradiation may, for example, be a xenon lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, an ultraviolet laser such as KrF or ArF, etc., more preferably a high-pressure mercury lamp, an ultra-high pressure mercury lamp or a metal halide. lamp. These lamps are preferred due to the greater luminous intensity of ultraviolet light with a wavelength of 313 nm. Polarized light can be irradiated by irradiating light from the aforementioned light source through an appropriate polarizing element. As the polarizer, a polarizer, a polarizer such as Glenn-Thompson, Glenn-Taylor, or a wire-grid polarizer can be used.

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

The method of applying the composition for forming a polarizing film on the alignment film in step (3) may, for example, be the same method as the method of applying the composition for forming an alignment film on the substrate. The obtained coating film of the composition for forming a polarizing film forms a dry coating film by removing the solvent by drying or the like under the condition that the polymerizable liquid crystal compound (B-1) contained in the coating film is not polymerized. As a drying method, the method similar to the method of drying the coating film of the composition for alignment film formation is mentioned. Also, when the compound (A-2) in the composition for forming an alignment film is a compound having an active hydrogen-containing group, the solvent in the coating film of the composition for forming a polarizing film is dried, and the compound (A-2) is The active hydrogen-containing group possessed by -2) reacts with the active hydrogen reactive group possessed by the compound (B-2) to form a bond derived from these functional groups. Thereby, higher adhesion between the alignment film and the polarizing film can be ensured.

Furthermore, in order to make the phase transition of the polymerizable liquid crystal compound (B-1) into a liquid phase, the temperature is raised to a temperature above the temperature at which the polymerizable liquid crystal compound (B-1) phase transitions into a liquid phase, and then the temperature is lowered to make the polymerizable liquid crystal compound (B-1) 1) Phase transition to liquid crystal phase (smectic phase). The phase transfer can be carried out after the solvent in the coating film in step (3) is removed, and can also be carried out simultaneously with the removal of the solvent.

In step (4), the polymerizable liquid crystal compound (B-1) is polymerized while maintaining the liquid crystal state of the polymerizable liquid crystal compound (B-1), whereby a polarizing film can be formed as a composition for forming a polarizing film of hardening. As the polymerization method, a photopolymerization method is preferable. In photopolymerization, as the light irradiated to the dry coating film, it can be determined according to the type of the polymerizable liquid crystal compound (B-1) contained in the dry coating film (in particular, the polymerizable liquid crystal compound (B-1) has The type of the polymerizable group), the type of the polymerization initiator and the amount thereof are appropriately selected. As the light source, etc., the thing similar to what was illustrated in the formation of a photo-alignment film is mentioned. The irradiation energy is preferably set so that the irradiation intensity in the wavelength region effective for activation of the polymerization initiator is 10 to 5000 mJ/cm ² , more preferably 100 to 2000 mJ/cm ² . It is preferable to select the kind of the polymerizable liquid crystal compound (B-1) or the polymerization initiator constituting the composition for forming a polarizing film so that photopolymerization can be performed by ultraviolet light. In addition, during polymerization, the polymerization temperature can also be controlled by performing light irradiation while cooling and drying the coating film by appropriate cooling means. During photopolymerization, a patterned polarizing film can also be obtained by performing masking or developing.

Furthermore, the manufacturing method of the polarizing element of the present invention may further include: a step of forming an overcoat layer on the polarizing film formed in step (4).

For example, when the overcoat layer is formed of a resin composition containing a water-soluble polymer, the resin composition containing a water-soluble polymer is applied to the surface of the polarizing film opposite to the alignment film, and the coating is dried and removed. The solvent in it makes it harden, so that the outer coating can be obtained.

The method of applying the resin composition containing a water-soluble polymer is not particularly limited, and examples thereof include the same method as the method of applying the composition for forming an alignment film.

The drying temperature and time for forming the overcoat layer from the coating film of the water-soluble polymer-containing resin composition are not particularly limited, and may be appropriately determined according to the composition and the like of the water-soluble polymer-containing resin composition to be used. The drying treatment can be carried out, for example, by blowing hot air or the like, and the temperature thereof is usually 40 to 100°C, preferably within the range of 60 to 100°C. In addition, the drying time is usually 10 to 600 seconds.

The polarizing element of the present invention is a structure that achieves high bending resistance and can easily cope with ultra-thinning. For example, when the polarizing element includes a substrate, an alignment film, and a polarizing film, the total thickness can be set to 1.0 ~10.0 μm.

The polarizing element of the present invention can be used in various display devices. A display device is a device having a display element, including a light-emitting element or a light-emitting device as a light-emitting source. As the display device, 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 (for example, a field emission display device ( FED), surface field emission display device (SED)), electronic paper (display device using electronic ink or electrophoretic element, plasma display device, projection display device (for example, grid light valve imaging system (GLV) display device, Display devices with digital micromirror devices (DMDs) and piezoelectric ceramic displays, etc. Liquid crystal display devices also include transmissive liquid crystal display devices, semi-transmissive liquid crystal display devices, reflective liquid crystal display devices, direct-view liquid crystal display devices and projection Type liquid crystal display devices, etc. These display devices can be display devices that display two-dimensional images, and can also be stereoscopic display devices that display three-dimensional images. In particular, the polarizing element of the present invention can be preferably used In organic electroluminescence (EL) display devices and inorganic electroluminescence (EL) display devices, it can also be preferably used in liquid crystal display devices and touch panel display devices.

In addition, the polarizing element of the present invention can be preferably used in flat panel display devices, has a relatively high bending resistance and can also cope with ultra-thin configuration, and is also preferably used as a flexible display material. The flexible display material of the present invention can be preferably assembled in a flexible image display device. [Example]

Hereinafter, based on an Example and a comparative example, although this invention is demonstrated more concretely, this invention is not limited to a following example. "%" and "parts" in the examples mean % by mass and parts by mass, respectively, unless otherwise specified.

1. Example 1 (1) Preparation of composition for forming photo-alignment film Synthesis Example 1: Synthesis of Alignment Polymer 1 Alignment polymer 1 includes the following structural units. [Alignment Polymer 1] [Chem. 18]

[Synthetic scheme of alignment polymer 1] [Chem. 19]

[Synthesis of Compound (a1-1-1)] 50 g (258 mmol) of ferulic acid was dissolved in 360 g of methanol. To the obtained solution, 10 g of sulfuric acid was added at room temperature, and the temperature was raised until the solvent was refluxed, and then reacted under reflux for 2 hours. After cooling the obtained reaction solution, 150 g of ice and 150 g of water were added. The supernatant was removed by decantation, and 150 g of water at 5° C. was added to crystallize it. The obtained white crystals were filtered. Furthermore, the filtered white crystals were washed with 1 M aqueous sodium bicarbonate solution and water, and then vacuum-dried to obtain 22.2 g of compound (a1-1-1). The yield was 83% based on ferulic acid.

[Synthesis of compound (b1-1-1)] 25 g (120 mmol) of compound (a1-1-1) was dissolved in 250 g of dimethylacetamide. 33.19 g (240 mmol) of potassium carbonate and 1.99 g (12 mmol) of potassium iodide were added to the obtained solution. 6-Chlorohexanol was added dropwise to the obtained dispersion liquid, stirred at room temperature for 1 hour, and then stirred at 70° C. for 8 hours. The obtained reaction solution was filtered to remove insoluble matter. 200 g of methyl isobutyl ketone and 300 g of water were added to the filtrate, stirred, left still, liquid-separated, and the organic layer was recovered. 200 g of water was added to the recovered organic layer, and a series of washing operations including stirring, standing and liquid separation were repeated twice. The solvent was removed from the recovered organic layer by distillation under reduced pressure using an evaporator to obtain a crude product of compound (b1-1-1).

[Synthesis of compound (c1-1-1)] All the crude product of the above-mentioned compound (b1-1-1) was dissolved in 185 g of ethanol. 92 g of water and 14.41 g (360 mmol) of sodium hydroxide were added to the obtained solution, and stirred at 80° C. for 1 hour. The reaction solution was cooled to about 3°C, and thereafter, maintaining the temperature at 5°C or lower, 2 M aqueous hydrochloric acid was added to adjust the pH to 2. The white precipitate obtained by acid analysis was collected by filtration, washed twice with a mixed solution of 100 g of water and 80 g of methanol, and then vacuum-dried to obtain 30.4 g of compound (c1-1-1). The yield was 86% based on compound (a1-1-1).

[Synthesis of compound (M1-1-1)] 27.46 g (93 mmol) of compound (c1-1-1) was dissolved in 280 g of chloroform. 2.06 g of BHT (di-tert-butyl-hydroxytoluene) and 37.73 g (373 mmol) of triethylamine were added as polymerization inhibitors to the obtained solution, followed by stirring under ice-cooling. 29.26 g (260 mmol) of methacryloyl chloride was added dropwise to the reaction solution, followed by stirring at 5° C. or lower for 5 hours. 5.7 g of dimethylaminopyridine and 190 g of water were added to the obtained reaction solution, and stirred at room temperature for 12 hours. After standing still, recover the organic layer, add 100 g of 2 N hydrochloric acid aqueous solution to the organic layer, and repeat a series of cleaning operations such as stirring, standing, and liquid separation twice. The organic layer was recovered, 300 g of n-heptane was added, and the resulting crystals were collected by filtration and precipitated. After washing twice with a mixed solvent containing 100 g of water and 80 g of methanol, vacuum drying was performed to obtain 22.0 g of compound (M1-1-1). The yield was 65% based on compound (c1-1-1).

[Synthesis of Alignment Polymer 1] Add 1.00 g (2.76 mmol) of compound (M1-1-1) and 10 g of tetrahydrofuran to a Schlenk tube. After deoxygenation, let nitrogen flow, while adding 2.27 mg of azobisisobutyronitrile (AIBN) , stirred at 60°C for 72 hours. The obtained reaction solution was added to 200 g of toluene. The precipitate was collected by filtration, washed with heptane, and vacuum-dried to obtain 0.75 g of alignment polymer 1 . The yield was 75% based on compound (M1-1-1). According to the molecular weight of the obtained alignment polymer 1 measured by GPC, the number average molecular weight is 28200, the weight average molecular weight is about 51300, the Mw/Mn is 1.82, and the monomer content is 0.5%.

Synthesis Examples 2 and 3: Synthesis of Alignment Polymer 2 and Alignment Polymer 3 By the method described in Macromolecules, Vol.39, No.26, 9357 (2006), an alignment polymer 2 with the following structure was synthesized and alignment polymer 3. Furthermore, the values in brackets in the following structural formula represent the mole fraction of each structural unit relative to the total structural units of the alignment polymer 2 and the alignment polymer 3 . [chemical 20]

[chem 21]

The weight average molecular weight of the alignment polymer 2 is about 100,000, and the weight average molecular weight of the alignment polymer 3 is about 90,000.

Synthesis Example 4: Synthesis of Alignment Polymer 4 According to the synthesis method of Alignment Polymer 2 and Alignment Polymer 3 above, Alignment Polymer 4 with the following structure was synthesized. Furthermore, the values in brackets in the following structural formulas represent the mole fraction of each structural unit relative to the total structural units of the alignment polymer 4 . [chem 22]

The weight average molecular weight of the alignment polymer 4 is about 95,000.

Preparation of composition for photo-alignment film formation 2 parts of the above-prepared alignment polymer (alignment polymer 1) and 98 parts of o-xylene were mixed, and the mixture was stirred at 80° C. for 1 hour, whereby alignment polymer solution 1 was obtained. Next, in the obtained alignment polymer solution 1, 1.0 parts of 3-aminopropyl triethoxysilane (trade name: KBE -903, manufactured by Shin-Etsu Chemical Co., Ltd.), were mixed to obtain a composition for forming a photoalignment film.

・式(A-7)所表示之聚合性液晶化合物 25份 [化24]

・下述所示之二色性色素(1) 2.8份 [化25]

・下述所示之二色性色素(2) 2.8份 [化26]

・下述所示之二色性色素(3) 2.8份 [化27]

・聚合起始劑：2-二甲胺基-2-苄基-1-(4-𠰌啉基苯基)丁烷-1-酮(Irgacure 369；Ciba Specialty Chemicals公司製造) 6份 ・整平劑：聚丙烯酸酯化合物(BYK-361N；BYK-Chemie公司製造) 1.2份 ・化合物(B-2)：具有下述結構之化合物(商品名：Laromer(註冊商標)LR-9000，BASF公司製造) 2份 [化28]

・溶劑：環戊酮 250份 (2) Preparation of Polarizing Film Forming Composition The following components were mixed and stirred at 80° C. for 1 hour to obtain a polarizing film forming composition. As the polymerizable liquid crystal compound and dichroic dye, the polymerizable liquid crystal compound and azo dye described in the examples of JP-A-2013-101328 were used.・75 parts of polymerizable liquid crystal compound represented by formula (A-6) [Chem. 23]

・25 parts of polymerizable liquid crystal compound represented by formula (A-7) [Chem. 24]

・2.8 parts of the following dichroic pigment (1) [Chemical 25]

・2.8 parts of the following dichroic pigment (2) [Chemical 26]

・2.8 parts of dichroic pigment (3) shown below [Chemical 27]

・Polymerization initiator: 2-dimethylamino-2-benzyl-1-(4-𠰌linylphenyl)butan-1-one (Irgacure 369; manufactured by Ciba Specialty Chemicals) 6 parts ・Level Agent: 1.2 parts of polyacrylate compound (BYK-361N; manufactured by BYK-Chemie) ・Compound (B-2): a compound having the following structure (trade name: Laromer (registered trademark) LR-9000, manufactured by BASF) 2 servings [Chemical 28]

・Solvent: 250 parts of cyclopentanone

(3) Production of Acrylic Resin Film Based on the description of Japanese Patent Laid-Open No. 2020-56835, an acrylic resin film was produced. Polyfunctional acrylate monomer (ethylene oxide (12 units) dipentaerythritol hexaacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., "NK Ester A-DPH-12E"): 90 parts, urethane Acrylate polymer (urethane acrylate (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., "Ultraviolet UV-3310B"): 10 parts, radical polymerization initiator (phenyl bis(2,4,6- Trimethylbenzoyl)phosphine oxide (manufactured by BASF, "Irgacure 819")): 3 parts, solvent (methyl ethyl ketone): 10 parts were mixed, and stirred at 50° C. for 4 hours to obtain Composition for forming an acrylic resin layer. Corona treatment is performed on the release-treated surface of a release-treated polyethylene terephthalate film (SP-PLR382050 manufactured by LINTEC Co., Ltd.) (release film), and thereafter , the composition for forming the acrylic resin layer was applied by bar coating (#2 30 mm/s), and the resin layer was formed using a UV irradiation device (SPOT CURE SP-7; manufactured by Ushio Electric Co., Ltd.). The film layer of the composition was irradiated with ultraviolet light at an exposure dose of 500 mJ/cm ² (based on 365 nm) to obtain an acrylic resin film with an acrylic resin layer formed on the surface of the release film. The thickness of the acrylic resin layer was 1.5 μm.

(4) Production of polarizing element Cut the acrylic resin film produced above into a square (10 cm in length x 10 cm in width) as a substrate, and use a corona treatment device (AGF-B10 ; Manufactured by Kasuga Electric Co., Ltd.), treated once under the conditions of output 0.3 kW and processing speed 3 m/min. Coat the above-mentioned photoalignment film-forming composition on the corona-treated surface with a bar coater, dry at 80°C for 1 minute, and use a polarizing UV irradiation device (SPOT CURE SP- 7; manufactured by Ushio Electric Co., Ltd.), polarized UV exposure was carried out under the accumulated light amount of 100 mJ/cm ² to form a photo-alignment film. The thickness of the obtained optical alignment film was measured with an ellipsometer M-220 (manufactured by JASCO Corporation), and the result was 40 nm.

The composition for forming a polarizing film was coated on the obtained photo-alignment film using a bar coater, and then dried for 1 minute by a drying oven set at 120°C.

Thereafter, using a high-pressure mercury lamp (Unicure VB-15201BY-A, manufactured by Ushio Electric Co., Ltd.), irradiate ultraviolet rays (under a nitrogen atmosphere, wavelength: 365 nm, cumulative light intensity at a wavelength of 365 nm: 1000 mJ/cm ² ), borrow A polarizing film aligned with a polymerizable liquid crystal compound and a dichroic pigment is formed to obtain a polarizing element (1) comprising a base material/optical alignment film/polarizing film. At this time, when the thickness of the polarizing film was measured with an ellipsometer, it was 2.0 μm.

(5) Characteristic evaluation [Evaluation of Adhesiveness] The adhesiveness between the optical alignment film and the substrate in the obtained polarizing element (1) was evaluated by the following method.

(Bag test) Adhesion between the optical alignment film and the substrate in the obtained polarizing element (1) was evaluated by a 100-grid test ("grid adhesion test" in JIS) according to JIS D0202-1988. On the side surface of the substrate of the polarizing element of 10 cm×10 cm, a 10×10 grid-shaped damage penetrating to the substrate and photo-alignment film was drawn at an interval of 2 mm to make a grid. Adhesive tape (25 mm in width, manufactured by Nichiban) was completely attached to the surface of the grid made by the institute. Next, the adhesive tape was peeled off in a direction of 90° with respect to the surface.

The number of remaining unpeeled grids was measured to evaluate the adhesion. Furthermore, for the stripped grid, it was confirmed by X-ray photoelectron spectroscopy (XPS) that the stripped interface was between the photoalignment film and the substrate. The results are shown in Table 1.

[Evaluation of Optical Properties (Measurement of Polarization Py, Elemental Transmittance Ty)] The degree of polarization Py and the transmittance Ty of the single substance of the polarizing element were measured as follows. The transmittance (Ta ) and the transmittance (Tb) along the absorption axis. Regarding the bracket, the reference side is provided with a screen that cuts off 50% of the light. Use the following formulas (Formula 1) and (Formula 2) to calculate the transmittance and polarization degree of the single substance at each wavelength, and then use the 2-degree field of view (C light source) of JIS Z 8701 to correct the visual sensitivity to calculate the corrected single substance Transmittance (Ty) and sensitivity correction polarization (Py). The results are shown in Table 1. Single substance transmittance Ty(%)=(Ta+Tb)/2 (Formula 1) Degree of polarization Py(%)=(Ta－Tb)/(Ta+Tb)×100 (Formula 2)

[Evaluation of bending resistance] The evaluation of bending resistance was carried out as follows using the method of the general test method for coatings-bending resistance (cylindrical mandrel method) described in JIS-K-5600-5-1. Cut the polarizer (1) into a square of 25 mm×200 mm. Using the cylindrical mandrel method bending resistance tester type II (manufactured by TP Giken Co., Ltd.), under the conditions of temperature 25°C and relative humidity 55%RH, the polarized light of the cut out polarizing element (1) The film surface is wound on the outside of a mandrel rod with a diameter of 2 mm (bending radius R=1 mm), and the bending resistance test is carried out. In a dark room environment, visually confirm the polarizing element (1) after the test under the illumination through the light, observe the occurrence of peeling between the substrate and the alignment film, and judge the complete peeling as "×", and judge the peeling as visually recognized. Some of them were judged as "△", and those who did not recognize the peeling were judged as "◯". The results are shown in Table 1.

2. Examples 2-23 and Comparative Example 1 According to the composition recorded in Table 1, the types and addition amounts of the alignment polymer (A-1), compound (A-2) and compound (B-2) were changed, and the same sequence as in Example 1 was followed. A polarizing element was fabricated and evaluated. Table 1 shows the obtained results.

・X-12-1154(信越化學工業股份有限公司製造)：有機鏈型，含巰基 ・KR-519(信越化學工業股份有限公司製造)：矽酮低聚物，含巰基 ＜化合物(B-2)＞ ・Karenz A01(昭和電工股份有限公司製造)： [化30]

・Karenz BEI(昭和電工股份有限公司製造)： [化31]

・Karenz MOI-EG(昭和電工股份有限公司製造)： [化32]

In Examples 13 to 18, the following compound (A-2) and compound (B-2) were used. <Compound (A-2)> ・X-12-1172ES (manufactured by Shin-Etsu Chemical Co., Ltd.): [Chemical 29]

・X-12-1154 (manufactured by Shin-Etsu Chemical Co., Ltd.): organic chain type, containing mercapto group ・KR-519 (manufactured by Shin-Etsu Chemical Co., Ltd.): silicone oligomer, containing mercapto group )＞ ・Karenz A01 (manufactured by Showa Denko Co., Ltd.): [chemical 30]

・Karenz BEI (product made in Showa Denko Co., Ltd.): [chemical 31]

・Karenz MOI-EG (manufactured by Showa Denko Co., Ltd.): [化32]

In Table 1, the addition amount of the compound (A-2) represents the mass parts of the compound (A-2) relative to 100 mass parts of the alignment polymer (A-1), and the addition amount of the compound (B-2) represents the compound ( B-2) Parts by mass relative to 100 parts by mass of the polymerizable liquid crystal compound. [Table 1] Alignment film polarizing film Characteristic evaluation Alignment polymer (A-1) Compound (A-2) Compound (B-2) The number of residues in one hundred grid test/100 Bending test optical properties type Amount added (parts) type Amount added (parts) Ty Python Comparative example 1 Alignment Polymer 1 not added 0.0 LR-9000 2 0/100 x 42 98 Example 1 3-Aminopropyltriethoxysilane (KBE-903) 1.0 2 10/100 △ 42 98 Example 2 2.5 2 28/100 △ 42 98 Example 3 5.0 2 62/100 〇 42 98 Example 4 7.5 2 100/100 〇 42 98 Example 5 10.0 1 50/100 △ 42 98 Example 6 10.0 2 100/100 〇 42 98 Example 7 10.0 5 100/100 〇 40 94 Example 8 10.0 10 100/100 〇 37 89 Example 9 12.5 2 100/100 〇 42 98 Example 10 15.0 2 100/100 〇 41 97 Example 11 22.5 2 100/100 〇 40 95 Example 12 25.0 2 100/100 〇 38 90 Example 13 10.0 Karenz A01 2 52/100 △ 42 98 Example 14 10.0 Karenz BEI 2 50/100 △ 42 98 Example 15 10.0 Karenz MOI-EG 2 55/100 △ 42 98 Example 16 X-12-1172ES 10.0 LR-9000 2 93/100 〇 42 98 Example 17 X-12-1154 10.0 2 99/100 〇 42 98 Example 18 KR-519 10.0 2 99/100 〇 42 98 Example 19 3-Aminopropyltriethoxysilane 5.0 0 15/100 △ 42 98 Example 20 (KBE-903) 0.5 30/100 △ 42 98 Example 21 Alignment Polymer 2 3-Aminopropyltriethoxysilane (KBE-903) 10.0 LR9000 2 100/100 〇 42 98 Example 22 Alignment Polymer 3 3-Aminopropyltriethoxysilane (KBE-903) 10.0 LR9000 2 100/100 〇 42 98 Example 23 Alignment Polymer 4 3-Aminopropyltriethoxysilane (KBE-903) 10.0 LR9000 2 100/100 〇 42 98

Claims (21)

A polarizing element, which is formed by sequentially laminating a substrate, an alignment film and a polarizing film, The above-mentioned alignment film is formed by curing the composition for forming an alignment film, and The composition for forming an alignment film includes an alignment polymer (A-1), and Compound (A-2) having an active hydrogen reactive group. The polarizing element according to claim 1, wherein the polarizing film is formed by curing the composition for forming a polarizing film, and The composition for forming a polarizing film includes a polymerizable liquid crystal compound (B-1), A compound (B-2) having an active hydrogen reactive group, and Dichroic pigment (B-3). The polarizing element according to claim 1 or 2, wherein the compound (A-2) further has an active hydrogen-containing group. The polarizing element according to any one of claims 1 to 3, wherein the alignment polymer (A-1) is a polymer having a photoreactive group that undergoes a dimerization reaction. The polarizing element according to any one of claims 1 to 4, wherein the alignment polymer (A-1) is a (meth)acrylic polymer. The polarizing element according to any one of claims 1 to 5, wherein the weight average molecular weight of the alignment polymer (A-1) is not less than 10,000 and not more than 1,000,000. The polarizing element according to any one of claims 1 to 6, wherein the compound (A-2) is a silane coupling agent. The polarizing element according to any one of claims 1 to 7, wherein the compound (A-2) is a silane disulfide containing at least one functional group selected from the group consisting of a primary amine group, a secondary amine group, a hydroxyl group, and a mercapto group. mixture. The polarizing element according to any one of claims 1 to 8, wherein the content of the compound (A-2) is 1 to 30 parts by mass relative to 100 parts by mass of the alignment polymer (A-1). The polarizing element according to any one of claims 2 to 9, wherein the compound (B-2) further has a polymerizable group. The polarizing element according to claim 10, wherein the polymerizable group is a (meth)acryl group. The polarizing element according to any one of claims 2 to 11, wherein the compound (B-2) has one or more isocyanate groups and one or more (meth)acryl groups. The polarizing element according to any one of claims 2 to 12, wherein the content of the compound (B-2) is 0.1 to 12 parts by mass relative to 100 parts by mass of the polymerizable liquid crystal compound (B-1). The polarizing element according to any one of claims 2 to 13, wherein the dichroic pigment (B-3) comprises a compound represented by formula (I): K1 (-N=N-K2) _p -N=N-K3 (I) [In the formula (I), K1 and K3 independently represent a phenyl group that may have a substituent, a naphthyl group that may have a substituent, a phenylbenzoate group that may have a substituent, or one of the substituents that may have A valent heterocyclic group, K2 represents a phenylene group that may have a substituent, a naphthalene-1,4-diyl group that may have a substituent, a 4,4'-stilbene group that may have a substituent, or a stilbene group that may have a substituent Divalent heterocyclic group, p represents an integer of 0 to 4, when p is an integer of 2 or more, the plurality of K2 may be the same or different from each other, within the range of visible light absorption, -N=N- Bonds may be replaced by -C=C-, -COO-, -NHCO-, -N=CH- bonds]. The polarizing element according to any one of claims 2 to 14, wherein the polymerizable liquid crystal compound (B-1) is a liquid crystal compound exhibiting smectic liquid crystallinity. The polarizing element according to any one of claims 1 to 15, wherein the thickness of the substrate is not less than 1 μm and not more than 10 μm. The polarizing element according to any one of claims 1 to 16, wherein the surface of the polarizing film opposite to the alignment film includes an overcoat layer. A manufacturing method, which is a manufacturing method of a polarizing element formed by sequentially laminating a substrate, an alignment film, and a polarizing film, comprising the following steps: (1) Form a coating film of a composition for forming an alignment film comprising an alignment polymer (A-1) and a compound (A-2) having an active hydrogen reactive group on a substrate having a polar group, and make the The coating film is dried, whereby the active hydrogen reactive group possessed by the compound (A-2) reacts with the polar group possessed by the substrate to form a bond; (2) forming an alignment film by performing rubbing treatment or light irradiation on the dried coating film obtained in step (1); (3) On the alignment film obtained in step (2), a compound comprising a polymerizable liquid crystal compound (B-1), a compound (B-2) having an active hydrogen reactive group, and a dichroic dye (B-3) is formed. a coating film of the composition for forming a polarizing film, and drying the coating film; and (4) The polymerizable liquid crystal compound (B-1) and the dichroic dye (B-3) in the dried coating film obtained in step (3) are cured in an aligned state to form a polarizing film. The manufacturing method according to claim 18, further comprising: a step of forming an overcoat layer on the polarizing film formed in step (4). A flat panel display device comprising the polarizing element according to any one of Claims 1 to 17. A flexible display material comprising the polarizing element according to any one of Claims 1-17.