JP2021165821A - Phase difference film, polarizing plate, and liquid crystal display device - Google Patents

Abstract

To provide a phase difference film having high transparency.SOLUTION: A phase difference film has an optical alignment film and a liquid crystal polymer laminated therein. The optical alignment film is formed of a liquid crystal alignment agent for optical alignment that contains a polymer having a constitutional unit including a photoreactive structure on a side chain, and the constitutional unit including the photoreactive structure is heated to initiate a chemical reaction. The liquid crystal polymer is formed of a polymerizable liquid crystal composition.SELECTED DRAWING: None

Description

The present invention relates to a retardation film, a polarizing plate having the retardation film, and a liquid crystal display element having the polarizing plate. In particular, the present invention relates to a retardation film obtained by laminating a photoalignment film and a film formed from a liquid crystal polymer.

The liquid crystal polymer prepared by polymerizing the polymerizable liquid crystal composition is a retardation film, an optical compensation film, a reflection film, a selective reflection film, an antireflection film, a viewing angle compensation film, a liquid crystal alignment film, a polarizing element, and a circularly polarizing element. It can be used as a material for an elliptically polarized light element, a film having another optically anisotropic film, or a display element having an element.

In recent years, a retardation film using a liquid crystal polymer having a high front contrast has been proposed for the purpose of improving the display quality of a display device (Patent Documents 1 and 2).

Further, it has been proposed that by combining a specific alignment film and a polymerizable liquid crystal composition, the liquid crystal polymer is oriented in a high order and a retardation film having a high front contrast can be obtained (Patent Document 3).

The liquid crystal aligning agent for photoalignment contains a polymer having a structural unit containing a photoreactive structure, and it is known that the structural unit containing the photoreactive structure of the polymer causes a chemical reaction by heating. (Patent Document 4)

Japanese Unexamined Patent Publication No. 2016-051178 Japanese Unexamined Patent Publication No. 2018-076491 Japanese Unexamined Patent Publication No. 2018-095847 Japanese Unexamined Patent Publication No. 2019-204071

Patent Document 3 describes that a liquid crystal polymer having a high front contrast can be obtained by using an alignment film having an azobenzene structure. However, since the azobenzene structure has coloring, there is a problem that the transparency is low. An object of the present invention is to provide a retardation film having high transparency even when an alignment film having an azobenzene structure is used.

The present inventors have found that by combining an alignment film having a specific structure and a liquid crystal polymer, it is possible to provide a retardation film having high transparency and high front contrast, and have completed the present invention.

式（１）において、Ｒ^１およびＲ^２は、それぞれ独立して、水素、式（１−１）、または式（１−２）で表される基であり、Ｒ^１およびＲ^２の少なくとも一つは式（１−１）、または式（１−２）で表される基であり；
ベンゼン環上の一つ以上の水素は、トリフルオロメチル、炭素数１〜５のアルキル、炭素数１〜５のアルコキシ、炭素数１〜５のアルコキシカルボニル、炭素数１〜５のアルカノイル、または炭素数１〜５のアルカノイルオキシで置き換えられてもよく；
式（１−１）および式（１−２）において、Ｒ^３およびＲ^４は、それぞれ独立して、水素、炭素数１〜１０のアルキル、炭素数１〜１０のアルカノイル、炭素数１〜１０のアルキレンを含むアリールアルキレン、またはアリールカルボニルであり、＊は式（１）のＲ^１またはＲ^２に対応する位置への結合場所を表す。
［４］ 前記光配向膜が、ポリアミック酸、ポリイミド、ポリエステル、ポリアミド、ポリアミドーポリアミック酸コポリマー、ポリエステルーポリアミック酸コポリマー、およびポリアミドーポリアミック酸コポリマーからなる群から選ばれる少なくとも１つであるポリマーを含有する配向剤から形成されたものである、［１］〜［３］のいずれか１項に記載の位相差膜。
［５］ 前記光配向膜が、テトラカルボン酸二無水物とジアミンの反応生成物であるポリマーを含有する配向剤から形成されたものであって、前記ジアミンは下記式（２）で表されるジアミンを少なくとも１つ含有する、［１］〜［４］のいずれか１項に記載の位相差膜。

式（２）において、Ｒ^１およびＲ^２は、独立して、水素、式（１−１）、または、式（１−２）で表される基であるが、Ｒ^１およびＲ^２の少なくとも一つは式（１−１）、または、式（１−２）で表される基であり；
ベンゼン環上の一つ以上の水素は、トリフルオロメチル、炭素数１〜５のアルキル、炭素数１〜５のアルコキシ、炭素数１〜５のアルコキシカルボニル、炭素数１〜５のアルカノイル、または炭素数１〜５のアルカノイルオキシで置き換えられてもよく；
式（１−１）および式（１−２）において、Ｒ^３およびＲ^４は、それぞれ独立して、水素、炭素数１〜１０のアルキル、炭素数１〜１０のアルカノイル、炭素数１〜１０のアルキレンを含むアリールアルキレン、またはアリールカルボニルであり、＊は式（２）のＲ^１またはＲ^２に対応する位置への結合場所を表し；
Ｒ^５は、独立して、炭素数１〜２０のアルキレン、−ＣＯＯ−、−ＯＣＯ−、−ＮＨＣＯ−、−ＣＯＮＨ−、−Ｎ（ＣＨ_３）ＣＯ−、−ＣＯＮ（ＣＨ_３）−、または単結合であり、該直鎖アルキレンにおいて、−ＣＨ_２−の１つまたは隣接しない２つは−Ｏ−で置換されていてもよく；
Ｒ^６は、独立して、単環式炭化水素から誘導される二価基、縮合多環式炭化水素から誘導される二価基、複素環を有する二価基、または単結合である。
［６］ 液晶重合体が下記式（３）に記載の重合性液晶化合物を少なくとも１つを含む重合性液晶組成物から形成されたものである、［１］〜［５］のいずれか１項に記載の位相差膜。

式（３）中、
ｍは２〜７であり、
Ａ^１は独立して１，４−フェニレン、１，４−シクロへキシレン、１，４−シクロヘキセニレン、テトラヒドロピラン−２，５−ジイル、１，３−ジオキサン−２，５−ジイル、ナフタレン−２，６−ジイル、フルオレン−２，７−ジイル、またはインダノン−４，７−ジイルで表される二価の環であり、該二価の環において、少なくとも一つの水素はフッ素、塩素、トリフルオロメチル、炭素数１〜１０のアルキル、炭素数２〜１０のアルケニル、炭素数１〜１０のアルコキシ、炭素数１〜１０のアルコキシカルボニル、炭素数１〜１０のアルカノイル、炭素数１〜１０のアルカノイルオキシ、または重合性官能基を有する一価基で置き換えられてもよく、
Ｚ^１は独立して−ＯＣＨ_２−、−ＣＨ_２Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＦ_２Ｏ−、−ＯＣＦ_２−、−ＣＨ_２ＣＨ_２−、−ＣＦ_２ＣＦ_２−、−ＯＣＨ_２ＣＨ_２Ｏ−、−ＣＨ＝ＣＨＣＯＯ−、−ＯＣＯＣＨ＝ＣＨ−、−ＣＨ_２ＣＨ_２ＣＯＯ−、−ＯＣＯＣＨ_２ＣＨ_２−、−ＣＨ_２ＣＨ_２ＯＣＯ−、−ＣＯＯＣＨ_２ＣＨ_２−、−ＣＨ＝ＣＨ−、−Ｎ＝ＣＨ−、−ＣＨ＝Ｎ−、−Ｎ＝Ｃ（ＣＨ_３）−、−Ｃ（ＣＨ_３）＝Ｎ−、−Ｎ＝Ｎ−、−Ｃ≡Ｃ−、−ＣＨ＝Ｎ−Ｎ＝ＣＨ−、−Ｃ（ＣＨ_３）＝Ｎ−Ｎ＝Ｃ（ＣＨ_３）−、または炭素数４〜２０のアルキレンであり、該アルキレンにおいて少なくとも一つの−ＣＨ_２−は−Ｏ−で置き換えられてもよく、
Ｐ^１は独立して重合性官能基を有する一価基である。
［７］ 前記液晶重合体において、液晶分子がホメオトロピック配向、ホモジニアス配向、ツイスト配向、またはスプレイ配向のいずれかの配向形態をとってなる、［１］〜［６］のいずれか１項に記載の位相差膜。
［８］ ［１］〜［７］のいずれか１項に記載の位相差膜を有する偏光板。
［９］ ［１］〜［７］のいずれか１項に記載の位相差膜を有する液晶表示素子。 [1] A retardation film in which a photoalignment film and a liquid crystal polymer are laminated, and the photoalignment film is formed from a photoalignment liquid crystal alignment agent containing a polymer having a photoreactive structure. , A retardation film in which the photoreactive structure causes a chemical reaction by heating and the liquid crystal polymer is formed from a polymerizable liquid crystal composition.
[2] The retardation membrane according to [1], wherein the chemical reaction is a cyclization reaction.
[3] The retardation film according to [1] or [2], wherein the photoalignment film is formed from an alignment agent containing a polymer having a structure represented by the following formula (1).

In formula (1), R ¹ and R ² are independent groups represented by hydrogen, formula (1-1), or formula (1-2), and at least one of ^{R 1} and R ^2. One is a group represented by the formula (1-1) or the formula (1-2);
One or more hydrogens on the benzene ring are trifluoromethyl, alkyl with 1 to 5 carbons, alkoxy with 1 to 5 carbons, alkoxycarbonyl with 1 to 5 carbons, alkanoyl with 1 to 5 carbons, or carbon. May be replaced with alkanoyloxy of numbers 1-5;
In formulas (1-1) and (1-2), R ³ and R ⁴ are independently hydrogen, alkyl having 1 to 10 carbon atoms, alkanoyl having 1 to 10 carbon atoms, and 1 to 10 carbon atoms, respectively. It is an arylalkylene or an arylcarbonyl containing the alkylene of the above, and * represents the bonding location to the position corresponding to ^{R 1} or R ^{2 of the formula (1).}
[4] The photoalignment film contains at least one polymer selected from the group consisting of polyamic acid, polyimide, polyester, polyamide, polyamide polyamic acid copolymer, polyester polyamic acid copolymer, and polyamide polyamic acid copolymer. The retardation film according to any one of [1] to [3], which is formed from an opterifying agent.
[5] The photoalignment film is formed from an alignment agent containing a polymer which is a reaction product of tetracarboxylic dianhydride and diamine, and the diamine is represented by the following formula (2). The retardation film according to any one of [1] to [4], which contains at least one diamine.

In formula (2), R ¹ and R ² are independently represented by hydrogen, formula (1-1), or formula (1-2), but at least ^{R 1} and R ^2. One is a group represented by the formula (1-1) or the formula (1-2);
One or more hydrogens on the benzene ring are trifluoromethyl, alkyl with 1 to 5 carbons, alkoxy with 1 to 5 carbons, alkoxycarbonyl with 1 to 5 carbons, alkanoyl with 1 to 5 carbons, or carbon. May be replaced with alkanoyloxy of numbers 1-5;
In formulas (1-1) and (1-2), R ³ and R ⁴ are independently hydrogen, alkyl having 1 to 10 carbon atoms, alkanoyl having 1 to 10 carbon atoms, and 1 to 10 carbon atoms, respectively. It is an arylalkylene or an arylcarbonyl containing the alkylene of the above, and * represents the bonding location to the position corresponding to ^{R 1} or R ^{2 in the formula (2);}
R ⁵ independently has 1 to 20 carbon atoms of alkylene, -COO-, -OCO-, -NHCO-, -CONH-, -N (CH ₃ ) CO-, -CON (CH ₃ )-, or It is a single bond and in the linear alkylene, one or two non-adjacent _{-CH 2-may be substituted with -O-;}
R ⁶ is independently a divalent group derived from a monocyclic hydrocarbon, a divalent group derived from a fused polycyclic hydrocarbon, a divalent group having a heterocycle, or a single bond.
[6] Any one of [1] to [5], wherein the liquid crystal polymer is formed from a polymerizable liquid crystal composition containing at least one polymerizable liquid crystal compound represented by the following formula (3). The retardation film according to.

In equation (3),
m is 2 to 7
A ¹ is independently 1,4-phenylene, 1,4-cyclohexylene, 1,4-cyclohexenylene, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, naphthalene. A divalent ring represented by −2,6-diyl, fluorene-2,7-diyl, or indanone-4,7-diyl, in which at least one hydrogen is fluorine, chlorine, Trifluoromethyl, alkyl having 1 to 10 carbon atoms, alkenyl having 2 to 10 carbon atoms, alkoxy having 1 to 10 carbon atoms, alkoxycarbonyl having 1 to 10 carbon atoms, alkanoyl having 1 to 10 carbon atoms, carbon atoms 1 to 10 It may be replaced with an alkanoyloxy, or a monovalent group having a polymerizable functional group.
Z ¹ is independently -OCH _2- , -CH ₂ O-, -COO-, -OCO-, -CF ₂ O-, -OCF _2- , -CH ₂ CH _2- , -CF ₂ CF _2- , -OCH ₂ CH ₂ O-, -CH = CHCOO-, -OCOCH = CH-, -CH ₂ CH ₂ COO-, -OCOCH ₂ CH _2- , -CH ₂ CH ₂ OCO-, -COOCH ₂ CH _2- , -CH = CH-, -N = CH-, -CH = N-, -N = C (CH ₃ )-, -C (CH ₃ ) = N-, -N = N-, -C≡C-, -CH = NN = CH-, -C (CH ₃ ) = N-N = C (CH ₃ )-, or an alkylene having 4 to 20 carbon atoms, in which at least one -CH _2- May be replaced with −O−
P ¹ is a monovalent group having a polymerizable functional group independently.
[7] The item according to any one of [1] to [6], wherein in the liquid crystal polymer, the liquid crystal molecules take any orientation form of homeotropic orientation, homogeneous orientation, twist orientation, or spray orientation. Phase difference film.
[8] A polarizing plate having the retardation film according to any one of [1] to [7].
[9] A liquid crystal display element having the retardation film according to any one of [1] to [7].

The usage of terms in this specification is as follows.
In the present invention, the "liquid crystal compound" is a general term for (A) a compound having a liquid crystal phase as a pure substance and (B) a compound which is a component of a liquid crystal composition.

In the present invention, a "polymerizable group" is a functional group that gives a compound the ability to polymerize by light, heat, catalyst or other means to transform into a compound with a higher molecular weight. Acryloyl group, methacrylic group and the like are polymerizable groups.
In the present invention, the "hydrogen donor group" is a functional group in which hydrogen is adjacent to an atom having a higher electronegativity than carbon, such as a hydroxyl group, an amino group, or a carboxyl group.
In the present invention, the "photosensitive group" is a functional group peculiar to a compound that undergoes a reaction accompanied by a change in molecular structure due to excitation of electrons in the molecule. Examples of the reaction include a photodecomposition reaction and a photoisomerization reaction.

In the present invention, the "polymerizable compound" is a compound having a polymerizable group.
In the present invention, the "monofunctional compound" is a compound having one polymerizable group.
In the present invention, the "polyfunctional compound" is a compound having a plurality of polymerizable groups.
In the present invention, the "X functional compound" is a compound having X polymerizable groups. Here, X in the "X functional compound" is an integer.
In the present invention, the "polymerizable liquid crystal compound" is a liquid crystal compound and a compound having a polymerizable group.
In the present invention, the "non-liquid crystal polymerizable compound" is a polymerizable compound that does not have a liquid crystal phase by itself.

In the present invention, the "polymerizable liquid crystal composition" means a composition containing a polymerizable compound and a liquid crystal compound, and a composition containing a "polymerizable liquid crystal compound".

In the present invention, the "alignment film" is a film that aligns a liquid crystal display.
In the present invention, the "photoalignment film" is an alignment film formed by light.
In the present invention, the "base material with an alignment film" is a base material having an alignment film.
In the present invention, the "base material" is a general term for a base material with an alignment film and a base material without an alignment film.
In the present invention, the "liquid crystal polymer" is a film obtained by polymerizing a polymerizable liquid crystal composition.
In the present invention, the "liquid crystal polymer with a base material" is a product containing a base material obtained by polymerizing a polymerizable liquid crystal composition on the base material.

In the present invention, the "phase difference film" is an optical conversion element having optical anisotropy. The retardation film contains a liquid crystal polymer.

In the present invention, the “orientation” refers to a state in which the long axes (easy-orientation axes) of the liquid crystal molecules are aligned in a certain direction in a state where they can be optically used.
In the present invention, the "tilt angle" is an angle between the orientation direction of the liquid crystal molecules and the surface of the base material.
In the present invention, the "homogeneous orientation" means a state in which the tilt angle is 0 to 5 degrees and is uniaxially oriented in the azimuth direction with respect to the substrate plane.
In the present invention, the "homeotropic orientation" refers to a state in which the tilt angle is 85 to 90 degrees and the orientation is uniaxially oriented.
In the present invention, the "tilt orientation" represents a state in which the tilt angle is oriented so as to increase with the distance from the base material surface.
In the present invention, "twist orientation" means that the orientation direction of the liquid crystal molecules in the long axis direction is parallel to the base material, and as the liquid crystal molecules move away from the base material, the vertical line on the surface of the base material is used as an axis. , Refers to the orientation twisted in a stepped manner.

When the following description is given in the chemical formula, it means that the wavy line portion or * is the bonding position. Here, the following arbitrary is an arbitrary atom.

In the present invention, the "cyclization reaction" is a reaction described in JP-A-2019-204071 and the like.

In the present invention, "transparency" refers to the transmittance of the retardation film at a wavelength of 430 nm. For the transmittance, the transmission spectrum of the retardation film at 300 to 800 nm was measured using a spectrophotometer, and the transmittance at a wavelength of 430 nm was calculated.

In the present invention, "Re" is a retardation, which is a phase delay of abnormal light with respect to normal light. The phase difference function means lettering. When the thickness of the layer of the liquid crystal polymer is d and Δn is the birefringence, it is represented by Re = Δn · d.

In the present invention, "contrast" means that the orientation direction of the liquid crystal polymer with a base material and the axis of one of the polarizing plates are aligned between the two polarizing plates, and the liquid crystal polymer with a base material is arranged. It means the value of (brightness in parallel Nicol state) / (brightness in cross Nicol state).
In the present invention, the "cross-nicol state" refers to a state in which the polarization axes of the polarizing plates arranged opposite to each other are orthogonal to each other.
In the present invention, the "parallel Nicol state" refers to a state in which the polarization axes of the polarizing plates arranged opposite to each other coincide with each other.
≪Alignment film≫

By aligning the functional groups in contact with the liquid crystal compound in the alignment film in a certain direction, the orientation of the polymerizable liquid crystal can be induced in the azimuth and / or polar directions with respect to the plane of the base material.
A rubbing method in which the surface of the alignment film is rubbed with a cloth, a photoalignment method by irradiation with polarized light, and the like are methods for aligning the orientation in a certain direction.
In the present invention, the photo-orientation method is used because the orientation and the contrast of the liquid crystal polymer can be improved.

In the photo-alignment method, it is necessary to incorporate a photosensitive group in the alignment film. The photosensitive group is preferably an azobenzene structure, a cyclobutane structure, a cinnamic acid structure, a chalcone structure, or a coumarin derivative structure because it is oriented with a small amount of exposure.
In order to improve the contrast, an azobenzene structure or a cyclobutane derivative structure, which has a high anchor energy for the liquid crystal compound and easily orients the liquid crystal compound, is more preferable.
Multiple types of photosensitive groups can be used in combination.

式（２）において、Ｒ^１およびＲ^２は、独立して、水素、式（１−１）、または、式（１−２）で表される基であるが、Ｒ^１およびＲ^２の少なくとも一つは式（１−１）、または、式（１−２）で表される基であり；
ベンゼン環上の一つ以上の水素は、トリフルオロメチル、炭素数１〜５のアルキル、炭素数１〜５のアルコキシ、炭素数１〜５のアルコキシカルボニル、炭素数１〜５のアルカノイル、または炭素数１〜５のアルカノイルオキシで置き換えられてもよく；
式（１−１）および式（１−２）において、Ｒ^３およびＲ^４は、それぞれ独立して、水素、炭素数１〜１０のアルキル、炭素数１〜１０のアルカノイル、炭素数１〜１０のアルキレンを含むアリールアルキレン、またはアリールカルボニルであり、＊は式（２）のＲ^１またはＲ^２に対応する位置への結合場所を表し；
Ｒ^５は、独立して、炭素数１〜２０のアルキレン、−ＣＯＯ−、−ＯＣＯ−、−ＮＨＣＯ−、−ＣＯＮＨ−、−Ｎ（ＣＨ_３）ＣＯ−、−ＣＯＮ（ＣＨ_３）−、または単結合であり、該直鎖アルキレンにおいて、−ＣＨ_２−の１つまたは隣接しない２つは−Ｏ−で置換されていてもよく；
Ｒ^６は、独立して、単環式炭化水素から誘導される二価基、縮合多環式炭化水素から誘導される二価基、複素環を有する二価基、または単結合である。 <Diamine represented by formula (2)>
The diamine represented by the formula (2) used for producing the polyamic acid and its derivative according to the embodiment of the present invention will be described.

In formula (2), R ¹ and R ² are independently represented by hydrogen, formula (1-1), or formula (1-2), but at least ^{R 1} and R ^2. One is a group represented by the formula (1-1) or the formula (1-2);
One or more hydrogens on the benzene ring are trifluoromethyl, alkyl with 1 to 5 carbons, alkoxy with 1 to 5 carbons, alkoxycarbonyl with 1 to 5 carbons, alkanoyl with 1 to 5 carbons, or carbon. May be replaced with alkanoyloxy of numbers 1-5;
In formulas (1-1) and (1-2), R ³ and R ⁴ are independently hydrogen, alkyl having 1 to 10 carbon atoms, alkanoyl having 1 to 10 carbon atoms, and 1 to 10 carbon atoms, respectively. It is an arylalkylene or an arylcarbonyl containing the alkylene of the above, and * represents the bonding location to the position corresponding to ^{R 1} or R ^{2 in the formula (2);}
R ⁵ independently has 1 to 20 carbon atoms of alkylene, -COO-, -OCO-, -NHCO-, -CONH-, -N (CH ₃ ) CO-, -CON (CH ₃ )-, or It is a single bond and in the linear alkylene, one or two non-adjacent _{-CH 2-may be substituted with -O-;}
R ⁶ is independently a divalent group derived from a monocyclic hydrocarbon, a divalent group derived from a fused polycyclic hydrocarbon, a divalent group having a heterocycle, or a single bond.

The diamine represented by the formula (2) is useful as a raw material for polymers such as polyamic acid, polyimide, polyamide, partial polyimide, polyamic acid ester, polyamic acid-polyamide copolymer, and polyamideimide. The polymer synthesized by using the diamine of the present invention as a raw material can be used for a liquid crystal alignment film, an optical variant, a retardation film, an optical compensation film, an antireflection film, various films, an optical member, and the like.

Ｒ^３およびＲ^４は、それぞれ独立して、水素、炭素数１〜１０のアルキル、炭素数１〜１０のアルカノイル、炭素数１〜１０のアルキレンを含むアリールアルキレン、またはアリールカルボニルである。 Among the diamines represented by the formula (2), the formulas (4) to (4) to the formulas (4) to the formulas (4) to ( The diamine compound represented by 7) is preferable.

R ³ and R ⁴ are independently hydrogen, an alkyl having 1 to 10 carbon atoms, an alkanoyl having 1 to 10 carbon atoms, an aryl alkylene containing an alkylene having 1 to 10 carbon atoms, or an arylcarbonyl.

Among the diamine compounds represented by the formulas (4) to (7), the formulas (4-1) to (4-8) and the formulas (5-1) to (5) are due to the high liquid crystal orientation. −8), formula (6-1), formula (6-2), formula (7-1), and diamine compounds represented by formula (7-2) are preferable.

The compound represented by the formula (4) according to the embodiment of the present invention is obtained by reducing commercially available 5-nitroanthranic acid to obtain 2-amino-5-nitrophenylmethanol, and then subjecting it to an oxidation reaction of an aromatic amine. An azobenzene having a hydroxymethyl group at the ortho-position and a nitro group at the para-position of the azo group in the benzene ring is obtained. Subsequently, the hydroxyl group is used as a trifluoromethanesulfonic acid ester, and an alkoxy group is used in the nucleophilic substitution reaction. Finally, it is obtained by reducing the nitro group.

The compound represented by the formula (5) according to the embodiment of the present invention has 1-alkoxymethyl-3-nitrobenzene obtained from a commercially available 1-bromomethyl-3-nitrobenzene by a nucleophilic substitution reaction, and then the nitro group is reduced. To obtain 3-alkoxymethylaniline. Subsequently, it is obtained by synthesizing azobenzene by diazo coupling with 4-nitroaniline and reducing the nitro group.

The compound represented by the formula (6) according to the embodiment of the present invention is obtained by reducing commercially available 5-nitroanthranic acid to obtain 2-amino-5-nitrophenylmethanol, and then subjecting it to an oxidation reaction of an aromatic amine. An azobenzene having a hydroxymethyl group at the ortho-position and a nitro group at the para-position of the azo group in the benzene ring is obtained. Subsequently, the hydroxyl group is used as a trifluoromethanesulfonic acid ester, and an N, N'-dialkylamino group is used in the nucleophilic substitution reaction. Finally, it is obtained by reducing the nitro group.

The compound represented by the formula (7) according to the embodiment of the present invention is obtained from a commercially available 1-bromomethyl-3-nitrobenzene by a nucleophilic substitution reaction to obtain N, N'-dialkyl-1- (3-nitrophenyl) methaneamine. After that, the nitro group is reduced to obtain dialkylaminomethyl-3-nitrobenzene. Subsequently, it is obtained by synthesizing azobenzene by diazo coupling with 4-nitroaniline and reducing the nitro group.

These compounds can also be purified and used by recrystallization or column chromatography.

In order to provide a liquid crystal alignment agent which can be a liquid crystal alignment film having higher liquid crystal orientation, one of the raw materials among these compounds is the formula (5-2), the formula (5-3), and the formula (5-). It is preferable to use at least one of the diamine compounds represented by 5) and the formula (7-1).

<Tetracarboxylic dianhydride>
The tetracarboxylic dianhydride used for producing the polyamic acid and its derivative according to the embodiment of the present invention will be described. The tetracarboxylic dianhydride used in the present invention can be selected from known tetracarboxylic dianhydrides without limitation. Such tetracarboxylic acid dianhydrides are aromatic systems (including heteroaromatic ring systems) in which the dicarboxylic acid anhydride is directly bonded to the aromatic ring, and aliphatic systems in which the dicarboxylic acid anhydride is not directly bonded to the aromatic ring. It may belong to any group of systems (including heterocyclic systems).

式（ＡＮ−Ｉ）、式（ＡＮ−ＩＶ）および式（ＡＮ−Ｖ）において、Ｘは独立して単結合または−ＣＨ_２−である。式（ＡＮ−ＩＩ）において、Ｇは単結合、炭素数１〜２０のアルキレン、−ＣＯ−、−Ｏ−、−Ｓ−、−ＳＯ_２−、−Ｃ（ＣＨ_３）_２−、−Ｃ（ＣＦ_３）_２−、または下記式（Ｇ１３−１）で表される２価の基であり、このＧ中の−ＣＨ_２−は、−Ｏ−、−ＣＯ−、−ＮＨ−で置き換えられてもよい。

式（Ｇ１３−１）において、Ｇ^１３ａおよびＧ^１３ｂはそれぞれ独立して、単結合、−Ｏ−、−ＣＯＮＨ−、または−ＮＨＣＯ−で表される２価の基である。フェニレンは、１，４−フェニレンおよび１，３−フェニレンが好ましい。
式（ＡＮ−ＩＩ）〜式（ＡＮ−ＩＶ）において、Ｙは独立して下記の３価の基の群から選ばれる１つであり、結合手は任意の炭素に連結しており、この基の少なくとも１つの水素はメチル、エチルまたはフェニルで置き換えられてもよい。

式（ＡＮ−ＩＩＩ）〜式（ＡＮ−Ｖ）において、環Ａ^１０は炭素数３〜１０の単環式炭化水素から誘導される二価基または炭素数６〜３０の縮合多環式炭化水素から誘導される二価基であり、この基の少なくとも１つの水素はメチル、エチルまたはフェニルで置き換えられていてもよく、環に掛かっている結合手は環を構成する任意の炭素に連結しており、２本の結合手が同一の炭素に連結してもよい。 Preferable examples of such a tetracarboxylic dianhydride are formulas (AN-I) to (AN-V) from the viewpoints of easy availability of raw materials, ease of polymer production, and electrical characteristics of the film. Examples thereof include the tetracarboxylic dianhydride represented.

In formulas (AN-I), formulas (AN-IV) and formulas (AN-V), X is independently single-bonded or -CH _2- . In formula (AN-II), G is a single bond, alkylene with 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) _2- , -C ( CF ₃ ) _2- or a divalent group represented by the following formula (G13-1), and -CH _{2- in} this G is replaced with -O-, -CO-, -NH-. May be good.

In formula (G13-1), G ^13a and G ^13b are independently divalent groups represented by single bonds, -O-, -CONH-, or -NHCO-, respectively. Phenylene is preferably 1,4-phenylene and 1,3-phenylene.
In formulas (AN-II) to (AN-IV), Y is one independently selected from the group of trivalent groups below, and the bond is linked to any carbon, and this group. At least one hydrogen of the above may be replaced with methyl, ethyl or phenyl.

In formulas (AN-III) to (AN-V), ring A ¹⁰ is a divalent group derived from a monocyclic hydrocarbon having 3 to 10 carbon atoms or a fused polycyclic hydrocarbon having 6 to 30 carbon atoms. It is a divalent group derived from, at least one hydrogen of this group may be replaced with methyl, ethyl or phenyl, and the bond on the ring is linked to any carbon that makes up the ring. The two binders may be connected to the same carbon.

More specifically, tetracarboxylic dianhydrides represented by the following formulas (AN-1) to (AN-16-15) can be mentioned.

式（ＡＮ−１）において、Ｇ^１１は単結合、炭素数１〜１２のアルキレン、１，４−フェニレン、または１，４−シクロヘキシレンである。Ｘ^１１は独立して単結合または−ＣＨ_２−である。Ｇ^１２は独立して下記の３価の基のどちらかである。Ｒ^１１は独立して水素または−ＣＨ_３である。

Ｇ^１２が＞ＣＨ−であるとき、＞ＣＨ−の水素は−ＣＨ_３に置き換えられてもよい。Ｇ^１２が＞Ｎ−であるとき、Ｇ^１１が単結合および−ＣＨ_２−であることはなく、Ｘ^１１は単結合であることはない。 [Tetracarboxylic dianhydride represented by the formula (AN-1)]

In formula (AN-1), G ¹¹ is a single bond, alkylene with 1-12 carbon atoms, 1,4-phenylene, or 1,4-cyclohexylene. X ¹¹ is independently single-bonded or -CH _2- . G ¹² is independently one of the following trivalent groups. R ¹¹ is independently hydrogen or -CH ₃ .

When G ¹² is> CH-, the hydrogen in> CH- may be replaced by _{-CH 3.} When G ¹² is> N-, G ¹¹ is not single-bonded and -CH _2- , and X ¹¹ is not single-bonded.

式（ＡＮ−１−２）および（ＡＮ−１−１４）において、ｍは１〜１２の整数である。 Examples of the tetracarboxylic dianhydride represented by the formula (AN-1) include a compound represented by the following formula.

In equations (AN-1-2) and (AN-1-14), m is an integer of 1-12.

式（ＡＮ−２）中、Ｒ^６１は独立して、水素原子、炭素数１〜５のアルキル基、またはフェニル基である。 [Tetracarboxylic dianhydride represented by the formula (AN-2)]

In formula (AN-2), R ⁶¹ is independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a phenyl group.

［式（ＡＮ−３）で表されるテトラカルボン酸二無水物］

式（ＡＮ−３）において、環Ａ^１１はシクロヘキサン環またはベンゼン環である。 Examples of the tetracarboxylic dianhydride represented by the formula (AN-2) include a compound represented by the following formula.

[Tetracarboxylic dianhydride represented by the formula (AN-3)]

In formula (AN-3), ring A ¹¹ is a cyclohexane ring or a benzene ring.

［式（ＡＮ−４）で表されるテトラカルボン酸二無水物］

式（ＡＮ−４）において、Ｇ^１３は単結合、−（ＣＨ_２）ｍ−、−Ｏ−、−Ｓ−、−Ｃ（ＣＨ_３）_２−、−ＳＯ_２−、−ＣＯ−、−Ｃ（ＣＦ_３）_２−、または下記の式（Ｇ１３−１）で表される２価の基であり、ｍは１〜１２の整数である。環Ａ^１１はそれぞれ独立してシクロヘキサン環またはベンゼン環である。Ｇ^１３は環Ａ^１１の任意の位置に結合してよい。

式（Ｇ１３−１）において、Ｇ^１３ａおよびＧ^１３ｂはそれぞれ独立して、単結合、−Ｏ−、−ＣＯＮＨ−、または−ＮＨＣＯ−で表される２価の基である。フェニレンは、１，４−フェニレンまたは１，３−フェニレンが好ましい。 Examples of the tetracarboxylic dianhydride represented by the formula (AN-3) include a compound represented by the following formula.

[Tetracarboxylic dianhydride represented by the formula (AN-4)]

In formula (AN-4), G ¹³ is a single bond,-(CH ₂ ) m-, -O-, -S-, -C (CH ₃ ) _2- , -SO _2- , -CO-, -C. (CF ₃ ) _2- or a divalent group represented by the following formula (G13-1), and m is an integer of 1 to 12. Ring A ¹¹ is independently a cyclohexane ring or a benzene ring. G ¹³ may be coupled to any position on ring A ^11.

In formula (G13-1), G ^13a and G ^13b are independently divalent groups represented by single bonds, -O-, -CONH-, or -NHCO-, respectively. The phenylene is preferably 1,4-phenylene or 1,3-phenylene.

式（ＡＮ−４−１７）において、ｍは１〜１２の整数である。 Examples of the tetracarboxylic dianhydride represented by the formula (AN-4) include a compound represented by the following formula.

In the formula (AN-4-17), m is an integer of 1-12.

式（ＡＮ−５）において、Ｒ^１１は独立して水素または−ＣＨ_３である。ベンゼン環を構成する炭素原子に結合位置が固定されていないＲ^１１は、ベンゼン環における結合位置が任意であることを示す。 [Tetracarboxylic dianhydride represented by the formula (AN-5)]

In formula (AN-5), R ¹¹ is independently hydrogen or −CH ₃ . ^{R 11} in which the bond position is not fixed to the carbon atom constituting the benzene ring indicates that the bond position in the benzene ring is arbitrary.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-5) include a compound represented by the following formula.

In the above tetracarboxylic dianhydride, a suitable material for improving each property of the liquid crystal alignment film described later will be described. When it is important to improve the orientation of the liquid crystal, the compounds represented by the formulas (AN-1), the formula (AN-3), and the formula (AN-4) are preferable, and the compounds represented by the formula (AN-1-) are preferable. 2), the compound represented by the formula (AN-1-13), the formula (AN-3-2), the formula (AN-4-17), or the formula (AN-4-29) is more preferable, and the compound represented by the formula (AN-4-29) is more preferable. In AN-1-2), m = 4 or 8 is preferable, and in the formula (AN-4-17), m = 4 or 8 is preferable, and m = 8 is more preferable.

When it is important to improve the transmittance of the liquid crystal display element, the formula (AN-1-1), the formula (AN-1-2), the formula (AN-3-1), and the formula (AN-4-4) 17), Equation (AN-4-30), Equation (AN-5-1), Equation (AN-7-2), Equation (AN-10-1), Equation (AN-16-3), Equation (AN-16-3) The compound represented by AN-16-4) or the formula (AN-2-1) is preferable, and in the formula (AN-1-2), m = 4 or 8 is preferable, and the formula (AN-4-1) is preferable. In 17), m = 4 or 8 is preferable, and m = 8 is more preferable.

When it is important to improve the VHR of the liquid crystal display element, the formula (AN-1-1), the formula (AN-1-2), the formula (AN-3-1), and the formula (AN-4-17) ), Equation (AN-4-30), Equation (AN-7-2), Equation (AN-10-1), Equation (AN-16-3), Equation (AN-16-4), or Equation (AN-16-4). The compound represented by AN-2-1) is preferable, m = 4 or 8 is preferable in the formula (AN-1-2), and m = 4 or 8 is preferable in the formula (AN-4-17). Preferably, m = 8 is more preferable.

Improving the relaxation rate of the residual charge (residual DC) in the liquid crystal alignment film by reducing the volume resistance value of the liquid crystal alignment film is effective as one of the methods for preventing seizure. When this purpose is emphasized, the formula (AN-1-13), the formula (AN-3-2), the formula (AN-4-21), the formula (AN-4-29), or the formula (AN-) The compound represented by 11-3) is preferable.

<Diamines other than diamines represented by the formula (2)>
The diamine used for producing the polyamic acid and its derivative according to the embodiment of the present invention will be described. In producing the polyamic acid or its derivative according to the embodiment of the present invention, a diamine represented by the formula (2) can be selected without limitation from known diamines.

Diamines can be divided into two types according to their structure. That is, when the skeleton connecting two amino groups is viewed as a main chain, it is a group branched from the main chain, that is, a diamine having a side chain group and a diamine having no side chain group. In the following description, a diamine having such a side chain group may be referred to as a side chain type diamine. A diamine that does not have such a side chain group may be referred to as a non-side chain diamine. This side chain group is a group having an effect of increasing the pretilt angle.
By properly using the non-side chain diamine and the side chain diamine properly, it is possible to correspond to the pretilt angle required for each.

The side chain diamine is preferably used in combination to the extent that the characteristics of the present invention are not impaired. Further, it is preferable to select and use the side-chain type diamine and the non-side-chain type diamine for the purpose of improving the vertical orientation, VHR, seizure characteristics and orientation with respect to the liquid crystal display.

Known diamines are shown below.

式（ＤＩ−１−ａ）において、ｖは独立して１〜６の整数である。 In the above equation (DI-1), G ²⁰ is −CH _2- or equation (DI-1-a), and when G ²⁰ is −CH ₂₋ , at least one −CH ₂₋ is −. NH -, - may be replaced by O-, m is an integer from 1 to 12, at least one hydrogen of the alkylene may be replaced by ^{-OH, G 20} is the formula (DI-1-a) In the case of, m is 1.

In the formula (DI-1-a), v is independently an integer of 1-6.

In formula (DI-3), G ²¹ is independently single-bonded, -NH-, -NCH _3- , -O-, -S-, -S-S-, -SO _2- , -CO-,- COO-, -CONCH _3- , -CONH-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -,-(CH ₂ ) _m- , -O- (CH ₂ ) _m- O-, −N (CH ₃ ) − (CH ₂ ) _k −N (CH ₃ ) −, − ( _{OC 2} H ₄ ) _m −O −, −O −CH ₂ −C (CF ₃ ) ₂ −CH ₂ − O-, -O-CO- (CH ₂ ) _m -CO-O-, -CO-O- (CH ₂ ) _m- O-CO-,-(CH ₂ ) _m- NH- (CH ₂ ) _m- , -CO- (CH ₂ ) _k- NH- (CH ₂ ) _k -,-(NH- (CH ₂ ) m) _k- NH-, -CO-C ₃ H _6- (NH-C ₃ H ₆ ) _n- CO-, or -S- (CH ₂ ) _m -S-, where m is an independent integer of 1-12, k is an integer of 1-5, and n is 1 or 2. .. In equation (DI-4), s is an independently integer of 0-2.

In formula (DI-5), G ³³ is independently single-bonded, -NH-, -NCH _3- , -O-, -S-, -S-S-, -SO _2- , -CO-,- COO-, -CONCH _3- , -CONH-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -,-(CH ₂ ) _m- , -O- (CH ₂ ) _m- O-, −N (CH ₃ ) − (CH ₂ ) _k −N (CH ₃ ) −, − ( _{OC 2} H ₄ ) _m −O −, −O −CH ₂ −C (CF ₃ ) ₂ −CH ₂ − O-, -O-CO- (CH ₂ ) _m -CO-O-, -CO-O- (CH ₂ ) _m- O-CO-,-(CH ₂ ) _m- NH- (CH ₂ ) _m- , -CO- (CH ₂ ) _k- NH- (CH ₂ ) _k -,-(NH- (CH ₂ ) _m ) _k- NH-, -CO-C ₃ H _6- (NH-C ₃ H ₆ ) _n- CO-, or -S- (CH ₂ ) _m -S-, -N (Boc)-(CH ₂ ) _e- N (Boc)-, -NH- (CH ₂ ) _e- N (Boc)- , -N (Boc)-(CH ₂ ) _e- , a group represented by the following formula (DI-5a) or the following formula (DI-5b), and m is independently 1 to 12 It is an integer, k is an integer of 1-5, e is an integer of 2-10, and n is 1 or 2. Boc means tert-butoxycarbonyl.

At least one hydrogen of the cyclohexane ring and the benzene ring in the formulas (DI-2) to (DI-5) is -F, -Cl, an alkylene having 1 to 3 carbon atoms, -OCH ₃ , -OH, -CF. ₃ , -CO ₂ H, -CONH ₂ , -NHC ₆ H ₅ , may be replaced with phenyl, or benzyl, and in addition, in formula (DI-4), at least one hydrogen in the cyclohexane ring and the benzene ring It may be replaced with one selected from the group of groups represented by the following formulas (DI-4-a) to (DI-4-i), and in the formula (DI-5), G ³³ is used. At the time of single bond, at least one hydrogen of cyclohexane ring and benzene ring may be replaced with _{NHBoc or N (Boc) 2.}

A group in which the bond position of at least one hydrogen of the cyclohexane ring and the benzene ring is not fixed to the carbon atom constituting the ring indicates that the bond position in the ring is arbitrary. The bond position _{of -NH 2} to the cyclohexane ring or the benzene ring is any position except the bond position of ^{G 21} or G ^33.

式（ＤＩ−４−ａ）および式（ＤＩ−４−ｂ）において、Ｒ^２０は独立して水素または−ＣＨ_３である。式（ＤＩ−４−ｆ）および式（ＤＩ−４−ｇ）において、ｍは０〜１２の整数であり、Ｂｏｃはｔ−ブトキシカルボニル基である。

In formulas (DI-4-a) and (DI-4-b), R ²⁰ is independently hydrogen or −CH ₃ . In formulas (DI-4-f) and formula (DI-4-g), m is an integer from 0 to 12 and Boc is a t-butoxycarbonyl group.

式（ＤＩ−５−a）において、ｑは独立して０〜６の整数である。Ｒ^４４は水素、−ＯＨ、炭素数１〜６のアルキル、または炭素数１〜６のアルコキシである。

In equation (DI-5-a), q is an independent integer from 0 to 6. R ⁴⁴ is hydrogen, -OH, alkyl of 1 to 6 carbon atoms or alkoxy of 1 to 6 carbon atoms.

In formula (DI-13), R ²³ is independently an alkyl having 1 to 5 carbon atoms, an alkoxy or −Cl having 1 to 5 carbon atoms, p is independently an integer of 0 to 3, and q is an integer of 0 to 3 independently. It is an integer from 0 to 4.
In the formulas (DI-13) to (DI-16), _{the bonding position of −NH 2} bonded to the ring is an arbitrary position.

Specific examples of the following formulas (DI-1-1) to (DI-16-1) can be given as diamines having no side chain of the above formulas (DI-1) to (DI-16). can.

式（ＤＩ−１−７）および式（ＤＩ−１−８）において、ｋはそれぞれ独立して、１〜３の整数である。式（ＤＩ−１−9）においてｖは独立して１〜６の整数である。 An example of the diamine represented by the formula (DI-1) is shown below.

In the formula (DI-1-7) and the formula (DI-1-8), k is an integer of 1 to 3 independently. In equation (DI-1-9), v is an independent integer of 1-6.

Examples of diamines represented by the formulas (DI-2) to (DI-3) are shown below.

An example of the diamine represented by the formula (DI-4) is shown below.

式（ＤＩ−５−１）において、ｍは１〜１２の整数である。 An example of the diamine represented by the formula (DI-5) is shown below.

In equation (DI-5-1), m is an integer of 1-12.

式（ＤＩ−５−１２）および式（ＤＩ−５−１３）において、ｍは１〜１２の整数である。

式（ＤＩ−５−１６）において、ｖは１〜６の整数である。

In equations (DI-5-12) and (DI-5-13), m is an integer of 1-12.

In equation (DI-5-16), v is an integer of 1-6.

An example of the diamine represented by the formula (DI-13) is shown below.

In the above diamine, a suitable material for improving each property of the liquid crystal alignment film described later will be described. When it is important to further improve the orientation of the liquid crystal, the formula (DI-1-3), the formula (DI-5-1), the formula (DI-5-5), the formula (DI-5-9) ), Equation (DI-5-12), Equation (DI-5-13), Equation (DI-5-29), Equation (DI-6-7), Equation (DI-7-3), or Equation (DI-7-3). It is preferable to use the compound represented by DI-11-2). In the formula (DI-5-1), m = 2, 4 or 6 is preferable, and m = 4 is more preferable. In the formula (DI-5-12), m = 2 to 6 is preferable, and m = 5 is more preferable. In the formula (DI-5-13), m = 1 or 2 is preferable, and m = 1 is more preferable.

When it is important to improve the transmittance, Eq. (DI-1-3), Eq. (DI-2-1), Eq. (DI-5-1), Eq. (DI-5-5), Eq. It is preferable to use the diamine represented by (DI-5-24) or the formula (DI-7-3), and the compound represented by the formula (DI-2-1) is more preferable. In the formula (DI-5-1), m = 2, 4 or 6 is preferable, and m = 4 is more preferable. In the formula (DI-7-3), m = 2 or 3, n = 1 or 2, is preferable, and m = 3, n = 1 is more preferable.

When it is important to improve the VHR of the liquid crystal display element, the formula (DI-2-1), the formula (DI-4-1), the formula (DI-4-2), and the formula (DI-4-10) ), Equation (DI-4-15), Equation (DI-4-22), Equation (DI-5-28), Equation (DI-5-30), or Equation (DI-13-1). The compound is preferably used, and the diamine represented by the formula (DI-2-1), the formula (DI-5-1), or the formula (DI-13-1) is more preferable. In the formula (DI-5-1), m = 1 is preferable. In the formula (DI-5-30), k = 2 is preferable.

Improving the relaxation rate of the residual charge (residual DC) in the liquid crystal alignment film by reducing the volume resistance value of the liquid crystal alignment film is effective as one of the methods for preventing seizure. When this purpose is emphasized, Eq. (DI-4-1), Eq. (DI-4-2), Eq. (DI-4-10), Eq. (DI-4-15), Eq. (DI-5) -1), formula (DI-5-12), formula (DI-5-13), formula (DI-5-28), formula (DI-4-20), formula (DI-4-21), formula It is preferable to use the compound represented by (DI-7-12) or the formula (DI-16-1), and the formula (DI-4-1), the formula (DI-5-1), or the formula (DI). The compound represented by -5-13) is more preferable. In the formula (DI-5-1), m = 2, 4 or 6 is preferable, and m = 4 is more preferable. In the formula (DI-5-12), m = 2 to 6 is preferable, and m = 5 is more preferable. In the formula (DI-5-13), m = 1 or 2 is preferable, and m = 1 is more preferable. In the formula (DI-7-12), m = 3 or 4 is preferable, and m = 4 is more preferable.

In each diamine, a part of the diamine may be replaced with the monoamine in the range where the ratio of the monoamine to the diamine is 40 mol% or less. Such replacement can cause termination of the polymerization reaction when producing a polyamic acid, and can suppress further progress of the polymerization reaction. Therefore, by such replacement, the molecular weight of the obtained polymer (polyamic acid or derivative thereof) can be easily controlled, and for example, the coating properties of the liquid crystal alignment agent can be improved without impairing the effects of the present invention. Can be done. The diamine to be replaced with the monoamine may be one kind or two or more kinds as long as the effect of the present invention is not impaired. Examples of the monoamine include aniline, 4-hydroxyaniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine and n-. Undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, and n-eicosylamine. Can be mentioned.

The polyamic acid or a derivative thereof according to the embodiment of the present invention may further contain a monoisocyanate compound in its monomer. By including the monoisocyanate compound in the monomer, the terminal of the obtained polyamic acid or its derivative is modified and the molecular weight is adjusted. By using this terminal-modified polyamic acid or a derivative thereof, for example, the coating characteristics of the liquid crystal alignment agent can be improved without impairing the effects of the present invention. The content of the monoisocyanate compound in the monomer is preferably 1 to 10 mol% with respect to the total amount of the diamine and the tetracarboxylic dianhydride in the monomer from the above viewpoint. Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

<Monomer with photoreactive structure>
In producing the polyamic acid or its derivative according to the embodiment of the present invention, it can be used together with a monomer having a photoreactive structure other than the diamine represented by the formula (2). Other photoreactive structures include, for example, photoisomerized structures represented by formulas (P-1) to (P-3) that cause isomerization by irradiation with ultraviolet rays, and formulas that cause dimerization (P-5). Examples thereof include an optical quantification structure represented by the formula (P-7).

When the following description is given in the chemical formula, it means that * is the bond position.

式（ＩＩ）〜式（Ｖ）において、Ｒ^２ａおよびＲ^３ａは−ＮＨ_２を有する１価の有機基または−ＣＯ−Ｏ−ＣＯ−を有する１価の有機基であり、式（ＩＶ）においてＲ^４ａは２価の有機基であり、式（ＶＩ）においてＲ^５ａは独立して−ＮＨ_２または−ＣＯ−Ｏ−ＣＯ−を有する芳香環である。 The compounds having a photoisomerization structure represented by the formulas (P-1) to (P-3) include a group of compounds represented by the following formulas (II) to (VI) having good photosensitivity. It is preferably at least one selected, and the compound represented by the formula (V) is more preferable.

In formulas (II) to (V), R ^2a and R ^3a are _{monovalent organic groups having -NH 2} or -CO-O-CO-, and in formula (IV). R ^4a is a divalent organic group, and in formula (VI) R ^5a is an aromatic ring independently having -NH ₂ or -CO-O-CO-.

The photoisomerized structure may be incorporated into either the main chain or the side chain of the polyamic acid or its derivative in the present invention, but by incorporating it into the main chain, it can be suitably used for a transverse electric field type liquid crystal display element.

Examples of the material having the photoisomerization structure include the following formulas (II-1), formula (II-2), formula (III-1), formula (III-2), formulas (IV-1) to (IV-). 3), at least one selected from the group of compounds represented by the formulas (V-1) to (V-3), formula (VI-1), and formula (VI-2) may be preferably used. can.

In each of the above equations, a group whose bond position is not fixed to any of the carbon atoms constituting the ring indicates that the bond position in the ring is arbitrary, and in the equation (IV-3), r is 1 to 1. It is an integer of 10, and in equation (V-2), R ^6a is independently _{an integer of -CH 3} , -OCH ₃ , -CF 3, or -COOCH ₃ , and a is an independently integer of 0 to 2. , In the formula (V-3), ring A and ring B independently form a divalent group derived from a monocyclic hydrocarbon, a divalent group derived from a fused polycyclic hydrocarbon, and a heterocycle. At least one selected from the divalent groups having, R ^11a is a linear alkylene with 1 to 20 carbon atoms, -COO-, -OCO-, -NHCO- or -N (CH ₃ ) CO-. R ^12a is a linear alkylene, −COO−, −OCO−, −NHCO− or −N (CH ₃ ) CO− having 1 to 20 carbon atoms, and in R ^11a and R ^12a , the linear alkylene −CH. ₂ - one or two of may be replaced by ^-O-, R ^{7a to R 10a} are each _{independently, -F, -CH 3, -OCH 3} , -CF 3 or -OH, Yes, and be to e are independently integers from 0 to 4.

The compounds represented by the above formulas (V-1), (V-2) and (VI-2) can be particularly preferably used from the viewpoint of their photosensitivity. In the formula (V-2) and the formula (VI-2), the compound in which the bond position of the amino group is in the para position, and in the formula (V-2), the compound having a = 0 is the point of orientation thereof. Can be used more preferably. Further, the compound represented by the formula (IV-3) can be used for purposes other than exhibiting photosensitivity.

Tetracarboxylic dianhydrides or diamines having a structure capable of causing isomerization by ultraviolet irradiation represented by formulas (II-1) to (VI-2) are described in the following formulas (II-1) to (VI-2). It can be concretely expressed by -3).

式（ＩＶ−３−１）において、ｒは１から１０の整数である。

In formula (IV-3-1), r is an integer from 1 to 10.

Among these, by making the formulas (VI-1-1) to (V-3-8) compounds containing a structure capable of causing isomerization by ultraviolet irradiation, for photo-alignment with higher sensitivity to ultraviolet irradiation. A liquid crystal alignment agent can be obtained. Formula (V-1-1), formula (V-2-1), formula (V-2-4) to formula (V-2-11) and formula (V-3-1) to formula (V-3) By making -8) a compound containing a structure capable of causing isomerization by irradiation with ultraviolet rays, a liquid crystal alignment agent for photoalignment capable of orienting liquid crystal molecules more uniformly can be obtained.
Above all, the compound represented by the formula (V-2-1) can be more preferably used because it exhibits greater anisotropy when the liquid crystal alignment film is formed.

式（ＰＤＩ−１２）において、Ｒ^５４は炭素数１〜１０のアルキルまたはアルコキシであり、アルキルまたはアルコキシの少なくとも１つの水素はフッ素に置き換えられていてもよい。 Examples of the compound having a photoreactive structure represented by the formulas (P-5) to (P-7) include diamine compounds represented by the following formulas (PDI-9) to (PDI-13). ..

In formula (PDI-12), R ⁵⁴ is an alkyl or alkoxy having 1 to 10 carbon atoms, and at least one hydrogen of the alkyl or alkoxy may be replaced with fluorine.

The above formula (PDI-9) or (PDI-11) can be preferably used.

In the embodiment in which a (non-photosensitive) tetracarboxylic acid dianhydride having no photoreactive structure and a (photosensitive) tetracarboxylic acid dianhydride having a photoreactive structure are used in combination, the sensitivity of the liquid crystal alignment film to light is achieved. The photosensitive tetracarboxylic acid dianhydride is 0 to 0 with respect to the total amount of the tetracarboxylic acid dianhydride used as a raw material in producing the polyamic acid or a derivative thereof according to the embodiment of the present invention in order to prevent the decrease in the amount of the tetracarboxylic acid dianhydride. 70 mol% is preferable, and 0 to 50 mol% is more preferable. In addition, two or more photosensitive tetracarboxylic dianhydrides may be used in combination in order to improve the above-mentioned various characteristics such as sensitivity to light, electrical characteristics, and afterimage characteristics.

In the embodiment in which a diamine having no photoreactive structure (non-photosensitive) and a diamine having a photoreactive structure (photosensitive) are used in combination, in order to prevent a decrease in the sensitivity of the liquid crystal alignment film to light, the present invention is used. The photosensitive diamine is preferably 20 to 100 mol%, more preferably 50 to 100 mol%, based on the total amount of the diamine used as a raw material in producing the polyamic acid or a derivative thereof according to the embodiment. In addition, two or more photosensitive diamines may be used in combination in order to improve the above-mentioned various characteristics such as sensitivity to light and afterimage characteristics. As described above, the embodiment of the present invention includes the case where the total amount of the tetracarboxylic dianhydride is occupied by the non-photosensitive tetracarboxylic dianhydride, but even in that case, at least 20 mol% of the total amount of the diamine is photosensitive. It is required to be a sex diamine. As described above, the diamine represented by the formula (2) of the present invention may be used alone as a photosensitive diamine or may be used in combination with another photosensitive diamine. When used alone, the amount of diamine represented by the formula (2) is 20 to 100 mol% with respect to the total amount of diamine used as a raw material in producing the polyamic acid or its derivative according to the embodiment of the present invention. Preferably, 50-100 mol% is more preferred. When other photosensitive diamines are used in combination, the diamine represented by the formula (2) is preferably 20 to 90 mol%, preferably 50 to 90 mol%.

The liquid crystal alignment film, the optical variant, the retardation film, the optical compensation film, the antireflection film, various films, the optical member and the like, which are mentioned as applications of the polymer using the diamine of the present invention, relate to the embodiment of the present invention. It may be composed of one kind of polymer, or two or more kinds of polymers according to the embodiment of the present invention may be mixed. Among these applications, applications in which orientation is more important, for example, a retardation film, is preferably composed of one type of polymer according to the embodiment of the present invention.

<Additives>
Further, for example, the liquid crystal alignment agent of the present invention may further contain various additives. Examples of various additives include high molecular weight compounds other than polyamic acid and its derivatives, and low molecular weight compounds, which can be selected and used according to their respective purposes.

For example, examples of the polymer compound include polymer compounds that are soluble in organic solvents. It is preferable to add such a polymer compound to the liquid crystal alignment agent of the present invention from the viewpoint of controlling the electrical characteristics and orientation of the formed liquid crystal alignment film. Examples of the polymer compound include polyamide, polyurethane, polyurea, polyester, polyepoxyside, polyester polyol, silicone-modified polyurethane, and silicone-modified polyester.

Examples of the small molecule compound include the following materials. 1) When it is desired to improve the coatability, a surfactant that meets the purpose. 2) Antistatic agent when improvement of antistatic is required. 3) When you want to improve the adhesion to the substrate, use a silane coupling agent or a titanium-based coupling agent. 4) Imidization catalyst when imidization proceeds at low temperature. Examples of the silane coupling agent include silane coupling agents disclosed in Japanese Patent Application Laid-Open No. 2013-242526 and the like. A preferred silane coupling agent is 3-aminopropyltriethoxysilane. Examples of the imidization catalyst include imidization catalysts disclosed in Japanese Patent Application Laid-Open No. 2013-242526 and the like.

式（３）中、
ｍは２〜７であり、
Ａ^１は独立して１，４−フェニレン、１，４−シクロへキシレン、１，４−シクロヘキセニレン、テトラヒドロピラン−２，５−ジイル、１，３−ジオキサン−２，５−ジイル、ナフタレン−２，６−ジイル、フルオレン−２，７−ジイル、またはインダノン−４，７−ジイルで表される二価の環であり、該二価の環において、少なくとも一つの水素はフッ素、塩素、トリフルオロメチル、炭素数１〜１０のアルキル、炭素数２〜１０のアルケニル、炭素数１〜１０のアルコキシ、炭素数１〜１０のアルコキシカルボニル、炭素数１〜１０のアルカノイル、炭素数１〜１０のアルカノイルオキシ、または重合性官能基を有する一価基で置き換えられてもよく、
Ｚ^１は独立して−ＯＣＨ_２−、−ＣＨ_２Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＦ_２Ｏ−、−ＯＣＦ_２−、−ＣＨ_２ＣＨ_２−、−ＣＦ_２ＣＦ_２−、−ＯＣＨ_２ＣＨ_２Ｏ−、−ＣＨ＝ＣＨＣＯＯ−、−ＯＣＯＣＨ＝ＣＨ−、−ＣＨ_２ＣＨ_２ＣＯＯ−、−ＯＣＯＣＨ_２ＣＨ_２−、−ＣＨ_２ＣＨ_２ＯＣＯ−、−ＣＯＯＣＨ_２ＣＨ_２−、−ＣＨ＝ＣＨ−、−Ｎ＝ＣＨ−、−ＣＨ＝Ｎ−、−Ｎ＝Ｃ（ＣＨ_３）−、−Ｃ（ＣＨ_３）＝Ｎ−、−Ｎ＝Ｎ−、−Ｃ≡Ｃ−、−ＣＨ＝Ｎ−Ｎ＝ＣＨ−、−Ｃ（ＣＨ_３）＝Ｎ−Ｎ＝Ｃ（ＣＨ_３）−、または炭素数４〜２０のアルキレンであり、該アルキレンにおいて少なくとも一つの−ＣＨ_２−は−Ｏ−で置き換えられてもよく、
Ｐ^１は独立して重合性官能基を有する一価基である。 ≪Polymerizable liquid crystal compound≫
The polymerizable liquid crystal composition of the present invention contains one or more polymerizable liquid crystal compounds. As the polymerizable liquid crystal compound, a compound represented by the following formula (3) is preferable from the viewpoint of a wide temperature range of the liquid crystal phase, compatibility with an organic solvent, and easy control of wavelength dispersion.

In equation (3),
m is 2 to 7
A ¹ is independently 1,4-phenylene, 1,4-cyclohexylene, 1,4-cyclohexenylene, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, naphthalene. A divalent ring represented by −2,6-diyl, fluorene-2,7-diyl, or indanone-4,7-diyl, in which at least one hydrogen is fluorine, chlorine, Trifluoromethyl, alkyl having 1 to 10 carbon atoms, alkenyl having 2 to 10 carbon atoms, alkoxy having 1 to 10 carbon atoms, alkoxycarbonyl having 1 to 10 carbon atoms, alkanoyl having 1 to 10 carbon atoms, carbon atoms 1 to 10 It may be replaced with an alkanoyloxy, or a monovalent group having a polymerizable functional group.
Z ¹ is independently -OCH _2- , -CH ₂ O-, -COO-, -OCO-, -CF ₂ O-, -OCF _2- , -CH ₂ CH _2- , -CF ₂ CF _2- , -OCH ₂ CH ₂ O-, -CH = CHCOO-, -OCOCH = CH-, -CH ₂ CH ₂ COO-, -OCOCH ₂ CH _2- , -CH ₂ CH ₂ OCO-, -COOCH ₂ CH _2- , -CH = CH-, -N = CH-, -CH = N-, -N = C (CH ₃ )-, -C (CH ₃ ) = N-, -N = N-, -C≡C-, -CH = NN = CH-, -C (CH ₃ ) = N-N = C (CH ₃ )-, or an alkylene having 4 to 20 carbon atoms, in which at least one -CH _2- May be replaced with −O−
P ¹ is a monovalent group having a polymerizable functional group independently.

式（８）中、Ａ^２は独立して、１，４−フェニレン、１，４−シクロヘキシレン、ナフタレン−２，６−ジイルまたはピペラジン−１，４−ジイルであり、これらにおいて、少なくとも１つの水素は、フッ素、炭素数１〜１０のアルキル、炭素数２〜１０のアルケニル、炭素数１〜１０のアルコキシ、炭素数１〜１０のアルコキシカルボニル、炭素数１〜１０のアルカノイル、炭素数１〜１０のアルカノイルオキシ、または重合性官能基を有する１価基で置き換えられてもよく、
Ｚ^２は独立して、単結合、−ＣＨ_２ＣＨ_２−、−ＣＯＯ−、−ＯＣＯ−、−ＣＨ_２Ｏ−、−ＯＣＨ_２−、−ＯＣＨ_２ＣＨ_２Ｏ−、−ＣＨ＝ＣＨＣＯＯ−、−ＯＣＯＣＨ＝ＣＨ−、−ＣＨ_２ＣＨ_２ＣＯＯ−、−ＯＣＯＣＨ_２ＣＨ_２−、−ＣＨ_２ＣＨ_２ＯＣＯ−、または−ＣＯＯＣＨ_２ＣＨ_２−である。液晶重合体の高温環境下における位相差機能の悪化の抑制の観点から、少なくとも１つが、−ＣＨ_２ＣＨ_２ＣＯＯ−または−ＯＣＯＣＨ_２ＣＨ_２−であることが好ましい。
ａおよびｂは独立して、０から３の整数であり、かつａおよびｂの和は、２から６である。
Ｙ^２は独立して、単結合、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、または−ＯＣＯＯ−である。
Ｑ^２は独立して、単結合または炭素数１から２０のアルキレンであり、このアルキレンにおいて、少なくとも１つの−ＣＨ_２−は−Ｏ−、−ＣＯＯ−、または−ＯＣＯ−で置き換えられてもよい。
ＰＧはアクリロイルオキシ基またはメタクリロイルオキシである。
Ｇは１，４−フェニレン、１，４−シクロヘキシレン、フルオレン―２，７−ジイルまたは式（Ｇ−１）〜式（Ｇ−４）で表される基である。この１，４−フェニレン、１，４−シクロヘキシレン、およびフルオレン―２，７−ジイルにおいて、少なくとも１つの水素は、フッ素、炭素数１〜１０のアルキル、炭素数２〜１０のアルケニル、炭素数１〜１０のアルコキシ、炭素数１〜１０のアルコキシカルボニル、炭素数１〜１０のアルカノイル、炭素数１〜１０のアルカノイルオキシ、または重合性官能基を有する１価基で置き換えられてもよい。

More specifically, a compound represented by the following formula (8) is preferable.

In formula (8), A ² is independently 1,4-phenylene, 1,4-cyclohexylene, naphthalene-2,6-diyl or piperazin-1,4-diyl, wherein at least one of them is used. Hydrogen is fluorine, an alkyl having 1 to 10 carbon atoms, an alkenyl having 2 to 10 carbon atoms, an alkoxy having 1 to 10 carbon atoms, an alkoxycarbonyl having 1 to 10 carbon atoms, an alkanoyl having 1 to 10 carbon atoms, and 1 to 10 carbon atoms. It may be replaced with 10 alkanoyloxys, or monovalent groups with polymerizable functional groups.
Z ² is independently a single _{bond, -CH 2 CH 2 -, -} COO -, - OCO -, - CH 2 O -, - OCH 2 -, - OCH 2 CH 2 O -, - CH = CHCOO-, -OCOCH = CH-, -CH ₂ CH _{2 COO-, -OCOCH 2} CH _2- , -CH ₂ CH ₂ OCO-, or -COOCH ₂ CH _2- . From the viewpoint of suppressing deterioration of the phase difference function of the liquid crystal polymer in a high temperature environment, at least one is preferably _{-CH 2} CH ₂ COO- or -OCOCH ₂ CH _2-.
a and b are independently integers from 0 to 3, and the sum of a and b is 2 to 6.
Y ² is independently a single bond, -O-, -COO-, -OCO-, or -OCOO-.
Q ² is independently a single bond or an alkylene with 1 to 20 carbon atoms, in which at least one -CH _2- may be replaced by -O-, -COO-, or -OCO-. ..
PG is an acryloyloxy group or methacryloyloxy.
G is 1,4-phenylene, 1,4-cyclohexylene, fluorene-2,7-diyl or a group represented by the formulas (G-1) to (G-4). In the 1,4-phenylene, 1,4-cyclohexylene, and fluorene-2,7-diyl, at least one hydrogen is fluorine, an alkyl having 1 to 10 carbon atoms, an alkenyl having 2 to 10 carbon atoms, and a carbon number of carbon atoms. It may be replaced with an alkoxy of 1 to 10, an alkoxycarbonyl having 1 to 10 carbon atoms, an alkanoyl having 1 to 10 carbon atoms, an alkanoyloxy having 1 to 10 carbon atoms, or a monovalent group having a polymerizable functional group.

(In formulas (G-1) to (G-4), X ¹ is independently -CH _2- , -NH-, -O-, -S-, or -CO-, and this -CH ₂ In − or −NH−, at least one hydrogen may be replaced by an alkyl having 1 to 5 carbon atoms, X ² is independently −CH = or −N =, and Z ³ is independently single bonded. , -CH = CH-, -C≡C-, -CH = N-, -N = CH-, -CH = N-NR ^6- , -C (CH ₃ ) = N-NR ^6- or -CH = NN = CH-, where R ⁶ is a monovalent group independently having hydrogen, an alkyl having 1 to 10 carbon atoms or a polymerizable functional group, and T ¹ , T ⁴ and T ⁵ are respectively. It is a monovalent group having 6 to 14 π electrons, and T ² , T ³ and T ⁶ are independently hydrogen, trifluoromethyl, cyano, alkyl having 1 to 5 carbon atoms, and 2 to 2 carbon atoms. 5 alkenyl, 1 to 5 carbon alkoxy, 1 to 5 carbon alkoxycarbonyl, 1 to 5 carbon alkanoyl, 1 to 5 carbon alkanoyloxy, 1 to 5 carbon alkyl sulfide, or polymerizable It is a monovalent group having a functional group, and T ² and T ³ may form a 5- to 7-membered heterocycle or a cyclic ketone containing an oxygen atom, a nitrogen atom and a sulfur atom.

Hereinafter, preferred examples of the compound represented by the formula (8) will be shown.

Formulas (8-A-1) to (8-A-20), formulas (8-1-1) to formulas (8-1-5), formulas (8-2-1) to formulas (8-2) -6), formulas (8-3-1) to formulas (8-3-6), and formulas (8-4-1) to formulas (8-4-5), Y ² is independently single-bonded. , -O-, -COO-, -OCO-, or -OCOO-, where Q ² is independently a single bond or an alkylene with 1 to 20 carbon atoms, in which at least one -CH _2- It may be replaced by −O−, −COO−, or −OCO−, and PG ² is independently an acryloyloxy group or a methacryloyloxy group.

≪Additives to polymerizable liquid crystal composition≫
The polymerizable liquid crystal composition of the present invention may contain additives other than the polymerizable liquid crystal compound as long as the liquid crystal phase is not impaired.

Addition of a surfactant to the polymerizable liquid crystal composition improves the smoothness of the liquid crystal polymer. The addition of the nonionic surfactant to the polymerizable liquid crystal composition further improves the smoothness of the liquid crystal polymer.
Surfactants are classified into ionic surfactants and nonionic surfactants.

A nonionic surfactant is preferable because it has an effect of suppressing the tilt orientation of the liquid crystal polymer on the air interface side. Silicone-based nonionic surfactants, fluorine-based nonionic surfactants, vinyl-based nonionic surfactants, hydrocarbon-based nonionic surfactants, and the like are nonionic surfactants.

In order to improve the mechanical strength and chemical resistance of the surface of the liquid crystal polymer, a surfactant which is a polymerizable compound may be added to the polymerizable liquid crystal composition. As the surfactant which is a polymerizable compound, a surfactant which starts a polymerization reaction with ultraviolet rays is preferable.

Since the liquid crystal polymer tends to be uniformly oriented and the coatability of the polymerizable liquid crystal composition is improved, the surfactant in the polymerizable liquid crystal composition is 0. 01 to 5% by weight is preferable, and 0.05 to 1% by weight is more preferable.

A silicone-based nonionic surfactant is a linear polymer composed of a siloxane bond, such as a compound in which an organic group such as a polyether or a long-chain alkyl is introduced into a side chain and / or a terminal.

A compound having a perfluoroalkyl group or a perfluoroalkenyl group having 2 to 7 carbon atoms is a fluorine-based nonionic surfactant.
Examples of the vinyl-based nonionic surfactant include (meth) acrylic polymers having a weight average molecular weight of 1000 to 1000000.

The polymerizable liquid crystal composition of the present invention may contain a non-liquid crystal polymerizable compound. In order to maintain the liquid crystal phase, the total weight of the non-liquid crystal polymerizable compounds in the polymerizable liquid crystal composition is preferably 30% by weight or less based on the total amount of the polymerizable liquid crystal composition.

The addition of the polyfunctional non-liquid crystal polymerizable compound to the polymerizable liquid crystal composition can be expected to enhance the mechanical strength of the liquid crystal polymer, improve the chemical resistance, or both.
The non-liquid crystal polymerizable compound is typically a compound having one or more vinyl-based polymerizable groups.

Addition of a non-liquid crystal polymerizable compound having a polar group at the side chain and / or the terminal to the polymerizable liquid crystal composition can be expected to improve the adhesion between the liquid crystal polymer and the photoalignment film.
The carbon number of styrene, nuclear-substituted styrene, acrylonitrile, vinyl chloride, vinylidene chloride, vinylpyridine, N-vinylpyrrolidone, vinylsulfonic acid, fatty acid vinyl, α, β-ethylenically unsaturated carboxylic acid, and alkyl is 1 to 18. Alkyl ester of (meth) acrylic acid, hydroxyalkyl ester of (meth) acrylic acid having 1 to 18 carbon atoms, aminoalkyl ester of (meth) acrylic acid having 1 to 18 carbon atoms of aminoalkyl , Ether oxygen-containing alkyl ester of (meth) acrylic acid having 3 to 18 carbon atoms of ether oxygen-containing alkyl, N-vinylacetamide, pt-butyl benzoate vinyl, N, N-dimethylaminobenzoate vinyl, Vinyl benzoate, vinyl pivalate, vinyl 2,2-dimethylbutanoate, vinyl 2,2-dimethylpentanate, 2-methyl-2-vinylbutate, vinyl propionate, vinyl stearate, 2-ethyl-2- Vinyl methylbutanoate, dicyclopentanyloxyl ethyl (meth) acrylate, isobornyloxyl ethyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, dimethyl adamantyl (meth) acrylate, dicyclopentanyl (meth) ) Acrylate, dicyclopentenyl (meth) acrylate, 2-acryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid, 2-acryloyloxyethyl phthalic acid, 2-acryloyloxyethyl-2-hydroxy Polyalkylate such as ethylphthalic acid, 2-acryloyloxyethyl acid phosphate, 2-methacryloyloxyethyl acid phosphate, polyethylene glycol having a degree of polymerization of 2 to 100, polypropylene glycol, a copolymer of ethylene oxide and propylene oxide, etc. Mono (meth) acrylic acid ester of len glycol, or di (meth) acrylic acid ester or polyethylene glycol having a degree of polymerization of 2 to 100 capped with an alkyl having 1 to 6 carbon atoms at the end, polypropylene glycol, and ethylene oxide and propylene oxide. The mono (meth) acrylic acid ester of polyalkylene glycol, which is a copolymer with, is a non-liquidaceous polymerizable compound which is a monofunctional compound. Vinyl acetate and the like are "vinyl fatty acid". Acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid and the like are "α, β-ethylenically unsaturated carboxylic acids". Methoxyethyl ester, ethoxyethyl ester, methoxypropyl ester, methylcarbyl ester, ethylcarbyl ester, butylcarbyl ester, etc. are described as "ether oxygen-containing alkyl of (meth) acrylic acid having 3 to 18 carbon atoms of ether oxygen-containing alkyl. Esther ".

1,4-Butanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, neopentyl glycol diacrylate, dimethylol tricyclodecane diacrylate, triethylene glycol diacrylate, dipropylene glycol Diacrylate, tripropylene glycol diacrylate, tetraethylene glycol diacrylate, bisphenol A EO-added diacrylate, bisphenol A glycidyl diacrylate, polyethylene glycol diacrylate, and methacrylate compounds of these compounds are bifunctional non-liquidaceous polymerizable compounds. Is.

Pentaeristol triacrylate, trimethylolpropan triacrylate, trimethylol EO-added triacrylate, trisacryloyloxyethyl phosphate, tris (acryloyloxyethyl) isocyanurate, alkyl-modified dipentaerythritol triacrylate, EO-modified trimethylolpropane triacrylate Rate, PO-modified trimethylolpropane triacrylate, pentaerythritol tetraacrylate, alkyl-modified dipentaerythritol tetraacrylate, ditrimethylolpropanetetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, alkyl-modified dipentaerythritol pentaacrylate , Pentaeristol trimetaacrylate, trimethylolpropane trimetaacrylate, trimethylol EO-added trimetaacrylate, trimethacryloyloxyethyl phosphate, trimethacryloyloxyethyl isocyanurate, alkyl-modified dipentaerythritol trimetaacrylate, EO-modified Trimethylol Propane Trimethacrylate, PO Modified Trimethylol Propane Trimethacrylate, Pentaerythritol Tetramethacrylate, Alkyl Modified Dipentaerythritol Tetramethacrylate, Ditrimethylol Propanetetramethacrylate, Dipentaerythritol Hexamethacrylate, Dipentaerythritol Monohydroxy Pentamethacrylate, alkyl-modified dipentaerythritol pentamethacrylate and the like are trifunctional or higher functional polyfunctional non-liquidaceous polymerizable compounds.

The addition of the polymerization initiator optimizes the polymerization rate of the polymerizable liquid crystal composition. A photoradical initiator is preferable as the polymerization initiator because of the ease of the curing process.
1-Hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenylketone, 2,2-dimethoxy-1,2-diphenylethane-1-one , P-Phenylphenyl-2,4-bis (trichloromethyl) triazine, 2- (p-butoxystylyl) -5-trichloromethyl-1,3,4-oxadiazole, 9-phenylaclysine, 9,10- Benzphenazine, benzophenone / Michler's ketone mixture, hexaarylbiimidazole / mercaptobenzimidazole mixture, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, benzyldimethylketal, 2-methyl-1- [4- (Methylthio) Phenyl] -2-morpholinopropan-1-one, 2,4-diethylxanthone / p-dimethylaminomethyl benzoate mixture, benzophenone / methyltriethanolamine mixture, Adecaarclus N-1919, Adeca Arcles NCI-831, Adeca Arkles NCI-930, Adeca Arkles NCI-730, Omnirad 127, Omnirad 184, Omnirad 369, Omnirad 379, Omnirad 500, Omnirad 651, Omnirad 754, Omnirad 754, Omnirad 73 Omnirad 2022, Omnirad 2100, Omnirad 2959, Omnirad 4265, Irgacure OXE01, Irgacure OXE02, Omnirad MBF, Omnirad TPO and the like are photoradical initiators. Here, Adeka Arkulz, Omnirad, and Irgacure are registered trademarks.

From the viewpoint of improving the frontal contrast of the liquid crystal polymer, preventing stickiness, and preventing the retardation from changing with time, the total weight of the photoradical polymerization initiator in the polymerizable liquid crystal composition is determined by the polymerizable liquid crystal composition. With respect to the total amount, 1 to 30% by weight is preferable, 1 to 15% by weight is more preferable, and 3 to 10% by weight is further preferable.

A sensitizer may be added to the polymerizable liquid crystal composition together with the photoradical polymerization initiator. Sensitizers include isopropylthioxanthone, diethylthioxanthone, ethyl-4 dimethylaminobenzoate, and 2-ethylhexyl-4-dimethylaminobenzoate.

By adding the chain transfer agent to the polymerizable liquid crystal composition, the reaction rate of the polymerizable liquid crystal compound and the chain length of the polymer in the liquid crystal polymer can be adjusted. As the amount of the chain transfer agent increases, the reaction rate of the polymerizable liquid crystal compound decreases. As the amount of the chain transfer agent increases, the chain length of the polymer decreases.

Thiol derivatives, styrene dimer derivatives and the like are chain transfer agents.
Dodecanethiol, 2-ethylhexyl- (3-mercapto) propionate and the like are monofunctional thiol derivatives.

Trimethylolpropanetris (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptopropionate), 1,4-bis (3-mercaptobutyryloxy) butane, pentaerythritol tetrakis (3-mercaptobutyrate) , 1,3,5-Tris (3-mercaptobutyloxyethyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione and the like are polyfunctional thiol derivatives.

2,4-Diphenyl-4-methyl-1-pentene, 2,4-diphenyl-1-butene and the like are styrene dimer chain transfer agents.
The addition of the polymerization inhibitor to the polymerizable liquid crystal composition prevents the initiation of polymerization of the polymerizable liquid crystal composition and the solution of the polymerizable liquid crystal composition during storage. The addition of the polymerization inhibitor improves the storage stability of the polymerizable liquid crystal composition.

Polymerization inhibitors include (a) phenolic antioxidants, (b) sulfur-based antioxidants, (c) phosphoric acid-based antioxidants, and (d) hindered amine-based antioxidants. From the viewpoint of compatibility with the polymerizable liquid crystal composition and transparency of the liquid crystal polymer, a phenolic antioxidant is preferable. From the viewpoint of compatibility, a phenolic antioxidant having a t-butyl group at the ortho position of the hydroxyl group is preferable.

From the viewpoint of improving storage stability, preventing stickiness, and preventing changes in retardation over time, the total weight of the polymerization inhibitor in the polymerizable liquid crystal composition is based on the total amount of the polymerizable liquid crystal composition. It is preferably 0.01 to 5% by weight, more preferably 0.01 to 0.5% by weight.

The addition of an ultraviolet absorber to the polymerizable liquid crystal composition improves the weather resistance of the polymerizable liquid crystal composition.
The addition of a light stabilizer to the polymerizable liquid crystal composition improves the weather resistance of the polymerizable liquid crystal composition.
Addition of an antioxidant to the polymerizable liquid crystal composition improves the weather resistance of the polymerizable liquid crystal composition.
The addition of the silane coupling agent to the polymerizable liquid crystal composition improves the adhesion between the substrate and the liquid crystal polymer.

<< Polymerizable liquid crystal composition solution >>
It is preferable to add a solvent to the polymerizable liquid crystal composition in order to facilitate application to the photoalignment film.
From the viewpoint of compatibility between the polymerizable liquid crystal compound and the solvent, the content of the polymerizable liquid crystal composition in the polymerizable liquid crystal composition solution is preferably 5 to 50% by weight, more preferably 15 to 40% by weight.

Ester-based solvent, amide-based solvent, alcohol-based solvent, ether-based solvent, cyclic ether-based solvent, aromatic hydrocarbon-based solvent, halogenated aromatic hydrocarbon-based solvent, aliphatic hydrocarbon-based solvent, halogenated aliphatic hydrocarbon A system solvent, an alicyclic hydrocarbon solvent, a ketone solvent, an acetate solvent and the like are components of the solvent.

The ester-based solvent refers to a compound having an ester bond, which is a component of the solvent.
Alkyl acetate, ethyl trifluoroacetate, alkyl propionate, alkyl butyrate, dialkyl malonate, alkyl glycolate, alkyl lactate, monoacetin, γ-butyrolactone, γ-valerolactone and the like are ester solvents.

Methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, 3-methoxybutyl acetate, isobutyl acetate, pentyl acetate, isopentyl acetate and the like are alkyl acetates.

Methyl propionate, methyl 3-methoxypropionate, ethyl propionate, propyl propionate, butyl propionate and the like are alkyl propionates.
Methyl butyrate, ethyl butyrate, butyl butyrate, isobutyl butyrate, propyl butyrate and the like are alkyl butyrate.

Diethyl malonate and the like are dialkyl malonic acids.
Methyl glycolate, ethyl glycolate and the like are alkyl glycolates.
Methyl lactate, ethyl lactate, isopropyl lactate, n-propyl lactate, butyl lactate, ethylhexyl lactate and the like are alkyl lactates.

The amide-based solvent refers to a compound having an amide bond, which is a component of the solvent.
N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N-methylpropionamide, N, N-dimethylformamide, N, N-diethylformamide, N, N-diethylacetamide, N, N-dimethylacetamide dimethylacetamide , N-Methylcaprolactam, 1,3-dimethyl-2-imidazolidinone and the like are amide-based solvents.

The alcohol-based solvent refers to a compound having a hydroxyl group, which is a component of the solvent.
Methanol, ethanol, 1-propanol, 2-propanol, 1-methoxy-2-propanol, t-butyl alcohol, sec-butyl alcohol, butanol, 3-methoxybutanol, 2-ethylbutanol, n-hexanol, n-heptanol, n-octanol, 1-dodecanol, ethylhexanol, 3,5,5-trimethylhexanol, n-amyl alcohol, hexafluoro-2-propanol, glycerin, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, Dipropylene glycol, tripropylene glycol, hexylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 2,4-pentanediol, 2,5 -Hexanediol, 3-methyl-3-methoxybutanol, cyclohexanol, methylcyclohexanol, ethylene glycol monomethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether , Triethylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, Terpineol, dihydroterpineol, etc. are alcohols.

The ether solvent refers to a compound having an ether bond and which is a component of the solvent.
Ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, bis (2-propyl) ether, diethylene glycol methyl ethyl ether, dipropylene glycol dimethyl ether, anisole, cyclopentyl methyl ether, methyl T-butyl ether and the like are ether-based solvents.

The cyclic ether-based solvent refers to a cyclic compound having an ether bond, which is a component of the solvent.
1,4-dioxane, 1,3-dioxolane, tetrahydrofuran and the like are cyclic ether solvents.

The aromatic hydrocarbon-based solvent refers to a compound having an aromatic hydrocarbon and which is a component of the solvent.
Benzene, toluene, xylene, mesityrene, ethylbenzene, diethylbenzene, i-propylbenzene, n-propylbenzene, t-butylbenzene, s-butylbenzene, n-butylbenzene, tetralin and the like are aromatic hydrocarbon solvents.

Examples of the halogenated aromatic hydrocarbon solvent include chlorobenzene and 1,2-dichlorobenzene.
The aliphatic hydrocarbon solvent is hexane, heptane, myrcene or the like.

The halogenated aliphatic hydrocarbon solvent is chloroform, dichloromethane, carbon tetrachloride, dichloroethane, trichlorethylene, tetrachlorethylene and the like.
The alicyclic hydrocarbon solvent is cyclohexane, cycloheptane, decalin, α-pinene, β-pinene, D-limonene and the like.

The ketone solvent refers to a compound having a ketone structure and which is a component of the solvent.
Acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, cyclopentanone, methyl propyl ketone and the like are ketone solvents.

The acetic acid-based solvent refers to a compound having an acetoxy group, which is a component of the solvent.
Ethylene glycol monomethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate, methyl acetoacetate, 1-methoxy-2-propyl acetate, etc. However, it is an acetate-based solvent.

Various coating methods are used for applying the polymerizable liquid crystal composition solution. From the viewpoint of uniform film thickness of the coating film composed of the polymerizable liquid crystal composition, the coating methods include spin coating method, micro gravure coating method, gravure coating method, wire bar coating method, dip coating method, and spray coating method. , Slit coating method, die coating method and inkjet coating method are preferable.

In order to remove the solvent, it is preferable to heat-treat during drying when forming a coating film composed of a polymerizable liquid crystal composition. The heat treatment can be performed by using a hot plate, a drying oven, and blowing hot air or hot air.

In order to obtain the liquid crystal polymer of the present invention, processing means such as electron beam, ultraviolet rays, visible light, and infrared rays can be used for the coating film composed of the polymerizable liquid crystal composition. The wavelength range of the light irradiated to obtain the liquid crystal polymer is 150 to 500 nm. The preferred wavelength range of light is 250-450 nm, and the more preferred range is 300-400 nm.

As a light source of the light, a low-pressure mercury lamp, a high-pressure discharge lamp, and a short arc discharge lamp can be used. Bactericidal lamps, fluorescent chemical lamps, black lights and the like are low pressure mercury lamps. High-pressure mercury lamps, metal halide lamps, and the like are the high-pressure discharge lamps. Ultra-high pressure mercury lamps, xenon lamps, mercury xenon lamps and the like are short arc discharge lamps.

The liquid crystal polymer of the present invention can be arranged inside and outside the liquid crystal cell of the liquid crystal display element. Since the variation in the retardation of the liquid crystal polymer due to the thermal history is small and the elution of impurities from the liquid crystal polymer to the liquid crystal is small, the liquid crystal polymer can be arranged inside the liquid crystal cell.

The thickness of the liquid crystal polymer is appropriately selected depending on the intended purpose, but is preferably in the range of 0.1 to 10 μm, preferably 0.5 to 5 μm.
The in-cell retardation film of the present invention is a laminate of a photoalignment film and a liquid crystal polymer. The photoalignment film is less likely to cause alignment defects, and the tilt angle can be lowered. By using the photoalignment film, the viewing angle characteristics and contrast are improved.

≪Preparation of base material≫
<Preparation of alignment film>
An alignment film can be formed on the substrate by the following procedure (I) or procedure (II).
Procedure (I)
Procedure (I-1)
A solution containing a polyamic acid represented by a repeating unit of the formula (1) is applied onto a substrate and dried to form a coating film.
Procedure (I-2)
The coating film composed of the polyamic acid formed in the procedure (I-1) was calcined at a temperature equal to or higher than the imidization temperature to form an imidized coating film, followed by
Procedure (I-3)
The imidized coating film formed in step (I-2) is subjected to an orientation treatment to impart anisotropy, and an alignment film is formed on the substrate;
Procedure (II)
Procedure (II-1)
A solution containing a polyamic acid represented by a repeating unit of the formula (1) is applied onto a substrate and dried to form a coating film.
Procedure (II-2)
The coating film composed of the polyamic acid formed in the procedure (II-1) is subjected to an orientation treatment to impart anisotropy, and subsequently,
Procedure (II-3)
The coating film composed of the polyamic acid of step (II-2) is calcined at a temperature equal to or higher than the imidization temperature to form an imidized coating film, and an alignment film is formed on the substrate.

At this time, from the viewpoint of the film thickness and its uniformity, the offset printing method and the inkjet printing method are preferable in the formation of the liquid crystal polymer. In order to remove the solvent of the solution on the substrate, a hot plate, a drying oven, and a blowing of warm air and other heat treatments are simultaneously performed in any of the steps (I-1) to (I-2). Is preferable.

In order to improve the contrast of the liquid crystal polymer with a substrate, the photoalignment method is used in the procedure (I-3) or the procedure (II-2).

Low-pressure mercury lamps, high-pressure discharge lamps, short arc discharge lamps, etc. can be used for photoalignment processing. The sterilization lamp, fluorescent chemical lamp, black light and the like are the low pressure mercury lamps. High-pressure mercury lamps, metal halide lamps, and the like are the high-pressure discharge lamps. Ultra-high pressure mercury lamps, xenon lamps, mercury xenon lamps and the like are the short arc discharge lamps. Since the alignment film can be formed with a small amount of exposure, it is preferable to use linearly polarized light in the procedure (I-3) or the procedure (II-2). In order to prevent damage to the alignment film due to the backlight of the liquid crystal display device and visible light, it is preferable that the polyamic acid, which is the raw material of the coating film, has a light absorption wavelength of 400 nm or more.

<Creation of liquid crystal polymer with base material>
A liquid crystal polymer with a base material can be formed by the following procedure.
Procedure (III-1)
A solution containing the polymerizable liquid crystal compound represented by the formula (2) is applied to the alignment film on the substrate and dried to form a coating film.
Procedure (III-2)
At a temperature at which the coating film exhibits a liquid crystal phase,
Procedure (III-3)
The coating film is exposed to prepare a liquid crystal polymer with a base material.

From the viewpoint of improving the adhesion between the liquid crystal polymer and the base material, it is preferable to heat the liquid crystal polymer with the base material after the procedure (III-3). The temperature of this heat treatment is equal to or lower than the durable temperature required for the liquid crystal polymer with a base material.

In step (III-1), from the viewpoint of the film thickness and its uniformity, the spin coating method, the micro gravure coating method, the gravure coating method, the wire bar coating method, the dip coating method, the spray coating method, the meniscus coating method and Application by the die coating method is preferable.

In the LCD, the liquid crystal polymer can be used for in-cell because the decrease in phase difference due to heating is small and the elution of impurities into the nematic liquid crystal is small.

By producing a liquid crystal polymer with a base material using a polarizing plate as a base material, a polarizing plate having a function such as optical compensation can be manufactured. By forming a 1/4 wavelength liquid crystal polymer on the polarizing plate, a liquid crystal polymer with a base material, which is a circular polarizing plate, can be produced. An absorption-type polarizing plate doped with iodine or a dichroic dye, and a reflective polarizing plate such as a wire grid polarizing plate can be the polarizing plate.

The present invention is not limited to published examples.
In the examples of the present invention, the room temperature is 25 ° C.

In the embodiment of the present invention, "NCI-930" is ADEKA ARKULS ™ NCI-930 manufactured by ADEKA CORPORATION.
In the embodiment of the present invention, "NCI-730" is ADEKA ARKULS ™ NCI-730 manufactured by ADEKA CORPORATION.
In the embodiment of the present invention, "FTX-218" is Futergent (trademark) FTX-218 manufactured by Neos Co., Ltd.
In the embodiment of the present invention, "TEGOFlow 370" is TEGOFlow 370 (trademark) manufactured by Evonik Japan Co., Ltd.
In the examples of the present invention, "F-556" is Megafvck ™ F-556, a fluorine-based surfactant manufactured by DIC Corporation.
In the examples of the present invention, the "additive A" is Daicel Corporation's epoxy resin, celoxide 8000.

In the examples of the present invention, "PGMEA" is propylene glycol monomethyl ether acetate.
In the examples of the present invention, "NMP" is N-methyl-2-pyrrolidone.

In the examples of the present invention, "BC" is ethylene glycol monobutyl ether.
In the examples of the present invention, "IPA" is 2-propanol.
In the embodiment of the present invention, the "wire grid polarizing plate" is UVT300A manufactured by Polatechno Co., Ltd.

In the embodiment of the present invention, the "ultra-high pressure mercury lamp" is a multi-light USH-250BY manufactured by Ushio, Inc.
In the examples of the present invention, the "polystyrene having a known molecular weight" is TSKgel standard polystyrene manufactured by Tosoh Corporation.

In an example of the present invention, the "gel permeation chromatograph" is a system consisting of a 2695 separation module manufactured by Waters and a 2414 differential refractometer manufactured by Waters.

In the examples of the present invention, the "gel permeation chromatograph column" is Shodex ™ GF-7M HQ.
In the embodiment of the present invention, the "polarization analyzer" is an OPIPRO polarization analyzer manufactured by Shintech Co., Ltd.

In the embodiment of the present invention, the "365 receiver" is a UVD-S365 manufactured by Ushio, Inc. connected to a UIT-150-A manufactured by Ushio, Inc.
In the embodiment of the present invention, the polarizing microscope is ECLIPSE E600 POL manufactured by Nikon Corporation.
In the embodiment of the present invention, the "luminance meter" is Yokogawa 3298F.
In the embodiment of the present invention, the "viscometer" is a TV-22 manufactured by Toki Sangyo Co., Ltd.
In the embodiment of the present invention, the "profilometer" is an Alpha Step IQ manufactured by KLA TECOR Co., Ltd.
<Measurement of weight average molecular weight>
The weight average molecular weight was determined by using a gel permeation chromatograph and using polystyrene having a known molecular weight as a standard substance. The temperature of the column during the development was set to 50 ° C. A phosphoric acid-NMP mixed solution was used as the developing solvent for the gel permeation chromatograph. The weight ratio of the phosphoric acid-NMP mixed solution was 0.6 / 100.

<Measurement of optical characteristics, etc.>
<Measurement by ellipsometry device>
The retardation of the retardation film was measured with an ellipsometry device at an incident angle of light of 0 °.

<Judgment of homogenius orientation>
Using an ellipsometry apparatus, the angle of incidence of light on the surface of the liquid crystal polymer was changed from −50 ° to 50 in 5 ° increments, and the retardation was measured. Here, the inclination direction of the incident angle of light is the same as the slow axis of the liquid crystal polymer. When both of the following conditions were satisfied, the liquid crystal polymer was considered to have a homogenous orientation.
The difference between the measured values of Re when (a) the retardation with respect to the incident angle of the liquid crystal polymer is convex upward and (b) the absolute value of the incident angle (absolute value) is the same is 5%. If it is within.

<Measurement of brightness in cross Nicol state>
The brightness in the cross Nicol state was measured by the following procedure.
(1) The retardation film is sandwiched between two polarizing plates, and both polarizing plates are arranged on a luminance meter so as to form a cross Nicol.
(2) The minimum brightness when the retardation film was rotated horizontally was defined as "brightness in the cross Nicol state".

<Measurement of brightness in parallel Nicole state>
The brightness in the parallel Nicol state was measured by the following procedure.
(1) The retardation film is sandwiched between two polarizing plates, and both polarizing plates are arranged in a luminance meter so as to form a parallel Nicol.
(2) The maximum brightness when the retardation film was rotated horizontally was defined as "brightness in the parallel Nicol state".

<Measurement of front contrast of liquid crystal polymer with base material>
The front contrast of the liquid crystal polymer with a base material was calculated by "brightness in the parallel Nicol state" / "brightness in the cross Nicol state".

<Adhesion test>
The adhesion test of the liquid crystal polymer with a base material was carried out according to the old JIS K5400 "General paint test method". In the examples herein, the results were classified by 5B-0B based on ASTM D 3559-B. The best is 5B.

5B: Smooth cut line, no peeling on any grid 4B: Slight peeling is seen at the intersection of the cut line, and less than 5% of the entire cut area is greatly affected 3B: Along the cut line, And peeling is seen at the intersection. 5% or more and 15% or less of the cut area is greatly affected. 2B: Wide peeling is seen on a part or the whole of the grid, and part or the whole of the board is peeled off here and there, the whole cut area. 15% or more and 35% or less of the above are greatly affected. 1B: Wide peeling is seen along the sides of the grid, and some grids are gathered together and part or all of them are peeled off. 35% or more and 65% or less of the cut area are greatly affected 0B: Those that do not correspond to the above classification

<Method of producing liquid crystal polymer>
The liquid crystal polymer was prepared by the following procedure.
Procedure (1) The polymerizable liquid crystal composition solution is spin-coated on a photoalignment film to prepare a coating film.
Procedure (2) Heat with a hot plate at 60 to 80 ° C. for 1 to 5 minutes to remove the solvent from the coating film.
Procedure (3) The coating film on the alignment film is irradiated with ultraviolet rays having a constant output at room temperature from a direction of 90 ° to prepare a film of a liquid crystal polymer. Here, the ultraviolet irradiation in the procedure (3) uses a 365 receiver and sets the irradiation time so that the exposure amount of the linearly polarized ultraviolet rays to the surface of the coating film on the substrate is 500 mJ / cm ^2. Adjusted between 5 and 40 seconds.

<Preparation of polyamic acid solution>
The polyamic acid solution was synthesized in the same manner as described in Japanese Patent Application Laid-Open No. 2012-193167.
The structures of the diamine and tetracarboxylic dianhydride used are shown below.

In the examples of the present invention, the compounds (DA-1) to the compound (DA-7) are compounds represented by the following formulas.

Commercially available products were used as the compound (DA-1), the compound (DA-3), the compound (DA-5), the compound (DA-6) and the compound (DA-7). Compound (DA-2), compound (DA-4), and compound were synthesized in accordance with Japanese Patent Application No. 2017-210174 and Japanese Patent Application Laid-Open No. 5634985, respectively.
In the examples of the present invention, the compounds (AA-1) to the compound (AA-4) are compounds represented by the following formulas.

Commercially available products were used as the compound (AA-2), the compound (AA-3), and the compound (AA-4). Compound (AA-1) was synthesized according to Japanese Patent Application Laid-Open No. 5407394.

[Example 1]
A polyamic acid solution is prepared to prepare a liquid crystal alignment agent for photoalignment in preparation for forming a retardation film.
0.58841 g of the compound (DA-1), in a 100 ml four-necked flask equipped with a thermometer, a stirrer, a raw material inlet and a nitrogen gas inlet, in the same manner as described in JP-A-2012-193167. 0.74487 g of compound (DA-2), 0.01540 g of compound (DA-3), 0.04396 g of compound (DA-4) and 22 g of NMP were added and stirred and dissolved under a nitrogen stream. Next, 0.93319 g of compound (AA-1), 0.45031 g of compound (AA-2), 0.22746 g of compound (AA-3) and 10 g of NMP were added, and the mixture was stirred at room temperature for 24 hours. 15 g of BC was added to the obtained solution and it was named a varnish solution. The varnish solution was stirred at 75 ° C. for 4 hours and named polyamic acid solution (PA-1). The viscosity of the polyamic acid solution (PA-1) was 9 mPa · s. The weight average molecular weight of the polyamic acid solution (PA-1) was 10,000.

[Example 2]
In the preparation of the polyamic acid solution (PA-1), compound (DA-1), compound (DA-2), compound (DA-3) compound (AA-1), compound (AA-2) and compound (AA-). 3) was replaced with the diamine and tetracarboxylic acid dianhydrides shown in Table 1 to prepare (PA-II) from a polyamic acid solution (PA-2) having a polymer solid content concentration of 6% by weight.

Table 1

<Creation of photo-alignment film>
[Example 3]
A base material with a photoalignment film was prepared by the following procedure.
(1) The polyamic acid solutions shown in Table 2 were mixed according to Examples 3 to 5, and NMP was added to the mixture to prepare an orienting agent having a polymer solid content concentration of 4% by weight.
(2) The photoaligning agent was spin-coated on a glass substrate at 2000 rpm.
(3) The obtained glass substrate was placed on a hot plate at 60 ° C. for 1 minute to remove the solvent in the photoaligning agent to prepare a coating film. (4) The coating film was subjected to room temperature. Then, linearly polarized light having a wavelength of 365 nm was irradiated with an energy of ^{2 J / cm 2 from the direction of 90 degrees to the coated surface.}
(5) After that, it was fired for 30 minutes in an oven set at 220 ° C. to obtain a photoalignment film.

[Example 4]
3.0 g of the polyamic acid solution (PA-1) synthesized in Example 1 and the polyamic synthesized in Example 2 in a 50 ml four-necked flask equipped with a thermometer, a stirrer, a raw material inlet and a nitrogen gas inlet. 7.0 g of acid solution (PA-I), 3.5 g of NMP and 1.5 g of BC were added, and the mixture was stirred at room temperature for 1 hour. A photoalignment film (AF-1) was prepared from the obtained solution using the method of Example 3.

[Example 5]
In the preparation of the orienting agent (AF-1), the polyamic acid solution (PA-1) and the polyamic acid solution (PA-I) were replaced with the polyamic acid solutions shown in Table 2, and the polymer solid content concentration was 4% by weight. Alignment agent was prepared. The obtained solution was formed into a film according to the method of Example 3 to prepare (AF-10) from the photoalignment film (AF-2).

[Comparative Example 1]
In the preparation of the aligning agent (AF-1), the polyamic acid solution (PA-1) and the polyamic acid solution (PA-I) were used as the polyamic acid solution (PA-6) and the polyamic acid solution (PA-I) shown in Table 2. A photoaligning agent having a polymer solid content concentration of 4% by weight was prepared by substituting with II). The photo-aligning agent was used to form a film according to the method of Example 3 to obtain a photo-aligning film (AF-11).

Table 2

化合物（８−Ａ−１３−１）は特願２０１６−１５６５５３に従い合成した。化合物（８−４−３−１）は特願２０１５−２４８２２６に従い合成した。化合物（８−Ａ−２−１）、化合物（８−Ａ−１−１）および化合物（８−Ａ−１−２）は特願２００８−３１４８２６に従い合成した。化合物（８−Ａ−１６−１）は特願２０１６−１７１０６６に従い合成した。化合物（８−２−６−１）は特願２０１５−１６３３５０に従い合成した。 <Adjustment of polymerizable liquid crystal composition>
The structure of the compound used in the polymerizable liquid crystal composition in the examples of the present invention is shown below.

Compound (8-A-13-1) was synthesized according to Japanese Patent Application No. 2016-156553. Compound (8-4-3-1) was synthesized according to Japanese Patent Application No. 2015-248226. Compound (8-A-2-1), compound (8-A-1-1) and compound (8-A-1-2) were synthesized according to Japanese Patent Application No. 2008-314826. Compound (8-A-16-1) was synthesized according to Japanese Patent Application No. 2016-171066. Compound (8-2-6-1) was synthesized according to Japanese Patent Application No. 2015-163350.

[Example 6]
A polymerizable liquid crystal composition (LC-1) was prepared by the following method.
0.8750 g of compound (8-A-13) and 0.3750 g of compound (8-4-3) were dissolved in 2.25 g of cyclohexanone and 1.5 g of PGMEA and 0.0875 g of NCI-930, 0. .013 g of AO-60 and 0.038 g of F-556 were further added and dissolved.
In the preparation of the polymerizable liquid crystal composition (LC-1), by changing the corresponding compound and its amount as shown in Table 3, the polymerizable liquid crystal composition (LC-2) can be changed to the polymerizable liquid crystal composition. (LC-6) was prepared. However, the total amount of the polymerizable liquid crystal compounds in the polymerizable liquid crystal composition is 18% by weight for (LC-2), 25% by weight for (LC-3), (LC-5) and (LC-6), and (LC). In -4), the amount of cyclohexane was adjusted so as to be 26% by weight.

Table 3

<Preparation of liquid crystal polymer with base material>
[Example 7]
A liquid crystal polymer with a base material was prepared by the following procedure.
(1) The polymerizable liquid crystal composition solution prepared in Example 7 was applied by spin coating onto a glass substrate with an alignment film prepared in Example 5 by spin coating.
(2) The base material is heated on a hot plate at 60 ° C. for 3 minutes.
(3) Subsequently, the base material was cooled at room temperature for 3 minutes.
(4) At room temperature in a nitrogen atmosphere, the polymerizable liquid crystal composition on the substrate is irradiated with light from an ultra-high pressure mercury lamp having a constant output from a direction perpendicular to the coating film on the substrate. The polymerizable liquid crystal composition on the base material was cured to obtain a liquid crystal polymer with a base material shown in Table 4.

However, using a 365 receiver, the irradiation time in step (4) was set to 5 so that the exposure amount of light from the ultrahigh pressure mercury lamp to the surface of the polymerizable liquid crystal composition ^{in step (4) was 500 mJ / cm 2.} Adjusted between seconds and 40 seconds.

Table 4

Table 5 shows the physical characteristics of the liquid crystal polymer with a substrate using the polymerizable liquid crystal composition solution as a raw material.
Table 5

When a liquid crystal polymer with a substrate was prepared from the photoalignment films (AF-1) to (AF-10) and the polymerizable liquid crystal compositions (LC-1) to (LC-4), the transmittance at 430 nm was 82. % Or more, and a highly transparent liquid crystal polymer can be obtained. However, when a liquid crystal polymer with a base material was prepared from the photoalignment film (AF-11), it was not possible to prepare a highly transparent liquid crystal polymer.

The liquid crystal polymer with a base material shown in Table 5 was further fired at 230 ° C. for 30 minutes to obtain a liquid crystal polymer with a base material. The characteristics after firing are shown in Table 6.

Table 6

When a liquid crystal polymer with a base material is prepared from the photoalignment film (AF-6) and the polymerizable liquid crystal composition (LC-1), a liquid crystal polymer having high adhesion can be obtained.

When a liquid crystal polymer with a base material was prepared from the photoalignment film (AF-11), it was not possible to prepare a highly transparent liquid crystal polymer.
From this, it was clarified that the liquid crystal polymer with a base material using the photoalignment film material of the present invention can obtain a liquid crystal polymer with a base material having high transparency.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a retardation film having high transparency and high frontal contrast even when an alignment film having an azobenzene skeleton and a liquid crystal polymer are combined, and a retardation film, an optical compensation film, an antireflection film, and a selection film can be provided. It can be used as a material for a reflective film, an antireflection film, a viewing angle compensating film, a liquid crystal alignment film, a polarizing element, a circular polarizing element, an elliptically polarizing element, a film having an optically anisotropic film, or a display element having an element. be.

Claims (9)

It is a retardation film in which a photoalignment film and a liquid crystal polymer are laminated, and the photoalignment film is formed from a photoalignment liquid crystal alignment agent containing a polymer having a photoreactive structure. A retardation film in which the reactive structure causes a chemical reaction by heating, and the liquid crystal polymer is formed from a polymerizable liquid crystal composition. The retardation membrane according to claim 1, wherein the chemical reaction is a cyclization reaction. The retardation film according to claim 1 or 2, wherein the photoalignment film is formed of an alignment agent containing a polymer having a structure represented by the following formula (1).

In formula (1), R ¹ and R ² are independent groups represented by hydrogen, formula (1-1), or formula (1-2), and at least one of ^{R 1} and R ^2. One is a group represented by the formula (1-1) or the formula (1-2);
One or more hydrogens on the benzene ring are trifluoromethyl, alkyl with 1 to 5 carbons, alkoxy with 1 to 5 carbons, alkoxycarbonyl with 1 to 5 carbons, alkanoyl with 1 to 5 carbons, or carbon. May be replaced with alkanoyloxy of numbers 1-5;
In formulas (1-1) and (1-2), R ³ and R ⁴ are independently hydrogen, alkyl having 1 to 10 carbon atoms, alkanoyl having 1 to 10 carbon atoms, and 1 to 10 carbon atoms, respectively. It is an arylalkylene or an arylcarbonyl containing the alkylene of the above, and * represents the bonding location to the position corresponding to ^{R 1} or R ^{2 of the formula (1).} An alignment agent containing a polymer whose photoalignment film is at least one selected from the group consisting of polyamic acid, polyimide, polyester, polyamide, polyamide polyamic acid copolymer, polyester polyamic acid copolymer, and polyamide polyamic acid copolymer. The retardation film according to any one of claims 1 to 3, which is formed from. The photoalignment film is formed from an alignment agent containing a polymer which is a reaction product of tetracarboxylic dianhydride and diamine, and the diamine is represented by at least one of the following formula (2). The retardation film according to any one of claims 1 to 4, which contains a diamine.

In formula (2), R ¹ and R ² are independently represented by hydrogen, formula (1-1), or formula (1-2), but at least ^{R 1} and R ^2. One is a group represented by the formula (1-1) or the formula (1-2);
One or more hydrogens on the benzene ring are trifluoromethyl, alkyl with 1 to 5 carbons, alkoxy with 1 to 5 carbons, alkoxycarbonyl with 1 to 5 carbons, alkanoyl with 1 to 5 carbons, or carbon. May be replaced with alkanoyloxy of numbers 1-5;
In formulas (1-1) and (1-2), R ³ and R ⁴ are independently hydrogen, alkyl having 1 to 10 carbon atoms, alkanoyl having 1 to 10 carbon atoms, and 1 to 10 carbon atoms, respectively. It is an arylalkylene or an arylcarbonyl containing the alkylene of the above, and * represents the bonding location to the position corresponding to ^{R 1} or R ^{2 in the formula (2);}
R ⁵ independently has 1 to 20 carbon atoms of alkylene, -COO-, -OCO-, -NHCO-, -CONH-, -N (CH ₃ ) CO-, -CON (CH ₃ )-, or It is a single bond and in the linear alkylene, one or two non-adjacent _{-CH 2-may be substituted with -O-;}
R ⁶ is independently a divalent group derived from a monocyclic hydrocarbon, a divalent group derived from a fused polycyclic hydrocarbon, a divalent group having a heterocycle, or a single bond. The retardation film according to any one of claims 1 to 5, wherein the liquid crystal polymer is formed from a polymerizable liquid crystal composition containing at least one polymerizable liquid crystal compound according to the following formula (3). ..

In equation (3),
m is 2 to 7
A ¹ is independently 1,4-phenylene, 1,4-cyclohexylene, 1,4-cyclohexenylene, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, naphthalene. A divalent ring represented by −2,6-diyl, fluorene-2,7-diyl, or indanone-4,7-diyl, in which at least one hydrogen is fluorine, chlorine, Trifluoromethyl, alkyl having 1 to 10 carbon atoms, alkenyl having 2 to 10 carbon atoms, alkoxy having 1 to 10 carbon atoms, alkoxycarbonyl having 1 to 10 carbon atoms, alkanoyl having 1 to 10 carbon atoms, carbon atoms 1 to 10 It may be replaced with an alkanoyloxy, or a monovalent group having a polymerizable functional group.
Z ¹ is independently -OCH _2- , -CH ₂ O-, -COO-, -OCO-, -CF ₂ O-, -OCF _2- , -CH ₂ CH _2- , -CF ₂ CF _2- , -OCH ₂ CH ₂ O-, -CH = CHCOO-, -OCOCH = CH-, -CH ₂ CH ₂ COO-, -OCOCH ₂ CH _2- , -CH ₂ CH ₂ OCO-, -COOCH ₂ CH _2- , -CH = CH-, -N = CH-, -CH = N-, -N = C (CH ₃ )-, -C (CH ₃ ) = N-, -N = N-, -C≡C-, -CH = NN = CH-, -C (CH ₃ ) = N-N = C (CH ₃ )-, or an alkylene having 4 to 20 carbon atoms, in which at least one -CH _2- May be replaced with −O−
P ¹ is a monovalent group having a polymerizable functional group independently. The retardation film according to any one of claims 1 to 6, wherein in the liquid crystal polymer, liquid crystal molecules take any orientation form of homeotropic orientation, homogenius orientation, twist orientation, or spray orientation. A polarizing plate having the retardation film according to any one of claims 1 to 7. A liquid crystal display element having the retardation film according to any one of claims 1 to 7.