阅读说明：本技术 化合物、液晶组合物及液晶表示元件 (Compound, liquid crystal composition and liquid crystal display element ) 是由 保坂和义 北浩 三木德俊 于 2018-02-27 设计创作，主要内容包括：通过将下述式[1a]的化合物用于液晶表示元件的液晶组合物,可实现本发明的目的。式中的符号的定义如说明书中所述。<Image he="88" wi="700" file="DDA0002249604810000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>(The object of the present invention can be achieved by using a compound represented by the following formula [1a ] in a liquid crystal composition for a liquid crystal display element. The symbols in the formula are defined in the specification.)

1. A compound represented by the following formula [1a ],

T1 represents a structure selected from the following formulae [2-1a ] to [2-7a ]; t2 represents a linear or branched alkylene group having 2 to 18 carbon atoms, and any-CH 2-in the alkylene group not adjacent to T1 and T3 is optionally replaced by-O-, -CO-, -COO-, -OCO-, -CONH-, -NHCO-, -NH-, a benzene ring or a cyclohexane ring; t3 represents a structure selected from the following formulae [1-1b ] to [1-4b ]; t4 represents a single bond or an alkylene group having 1 to 24 carbon atoms, and any-CH 2-in the alkylene group not adjacent to T3 is optionally replaced by-O-, -CO-, -COO-, -OCO-, -CONH-, -NHCO-, -NH-, -CON (CH3) -, -S-or-SO 2-; t5 represents a 2-valent cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, or a 2-valent organic group having 17 to 51 carbon atoms and having a steroid skeleton, wherein any hydrogen atom in the cyclic group is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms or a fluorine atom; t6 represents a single bond, -O-, -OCH2-, -CH2O-, -COO-or-OCO-; t7 represents a cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, wherein any hydrogen atom in the cyclic group is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms or a fluorine atom; t8 represents an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy group having 1 to 18 carbon atoms; mT represents an integer of 1 to 4; nT represents an integer of 0 to 4,

WA represents a hydrogen atom or a benzene ring,

TB represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

2. The compound according to claim 1, wherein the compound of formula [1a ] is the following formula [1b ] or formula [1c ],

t9, T11, T17 and T19 each represent a structure selected from the group consisting of the above-mentioned formulas [2-1a ] to [2-7a ]; t10 and T18 each represents a linear or branched alkylene group having 2 to 12 carbon atoms; t12 and T20 each represent a structure selected from the group consisting of the above-mentioned formulas [1-1b ] to [1-4b ]; t13 and T21 each represents a single bond or an alkylene group having 1 to 8 carbon atoms; t14 and T15 represent a benzene ring or a cyclohexane ring; t16 represents an alkyl or alkoxy group having 1 to 12 carbon atoms; t22 represents a C17-51 2-valent organic group having a steroid skeleton; pT represents an integer of 0 to 4.

3. A liquid crystal composition comprising at least 1 compound selected from the group consisting of the above-mentioned formula [1a ], formula [1b ] and formula [1c ].

4. A liquid crystal display element having a liquid crystal layer obtained by curing a liquid crystal composition containing a liquid crystal and a polymerizable compound, which is disposed between 1 pair of substrates having electrodes, by irradiating the composition with ultraviolet light, wherein at least one surface of the substrates has a liquid crystal alignment film capable of vertically aligning the liquid crystal,

The liquid crystal composition contains at least 1 compound selected from the group consisting of the above-mentioned formula [1a ], formula [1b ] and formula [1c ].

5. The liquid crystal display element according to claim 4, wherein the liquid crystal composition comprises a compound represented by the following formula [2a ],

W1 represents a structure selected from the following formulae [2-1a ] to [2-7a ]; w2 represents a single bond, -O-, -COO-or-OCO-; w3 represents a single bond or an alkylene group having 1 to 12 carbon atoms; w4 represents a single bond, -O-, -COO-or-OCO-; w5 represents a benzene ring, a cyclohexane ring or a C17-51 organic group having a steroid skeleton; w6 represents a single bond, -CH2-, -CH2O-, -OCH2-, -O-, -COO-, -OCO-, -NHCO-or-CONH-; w7 represents a benzene ring or a cyclohexane ring; w8 represents an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy group having 1 to 18 carbon atoms; mW represents an integer of 0 to 4,

WA represents a hydrogen atom or a benzene ring.

6. The liquid crystal display element according to claim 4 or claim 5, wherein the liquid crystal alignment film is a liquid crystal alignment film obtained from a liquid crystal alignment treatment agent containing a polymer having a side chain structure of the following formula [4-1a ] or formula [4-2a ],

X1 and X3 respectively represent a single bond, - (CH2) a-, -O-, -CH2O-, -COO-or-OCO-, and a is an integer of 1-15; x2 represents a single bond or- (CH2) b-, b represents an integer of 1 to 15; x4 represents a 2-valent cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, or a 2-valent organic group having 17 to 51 carbon atoms and having a steroid skeleton, wherein any hydrogen atom in the cyclic group is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms or a fluorine atom; x5 represents at least 1 cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, wherein any hydrogen atom on the cyclic groups is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluoroalkyl group having 1 to 3 carbon atoms, a fluoroalkoxy group having 1 to 3 carbon atoms or a fluorine atom; x6 represents an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy group having 1 to 18 carbon atoms; n represents an integer of 0 to 4,

-X-X [4-2a]

x7 represents a single bond, -O-, -CH2O-, -CONH-, -NHCO-, -CON (CH3) -, -N (CH3) CO-, -COO-or-OCO-; x8 represents an alkyl group having 8 to 18 carbon atoms or a fluoroalkyl group having 6 to 18 carbon atoms.

7. The liquid crystal display element according to claim 6, wherein the liquid crystal alignment treatment agent contains at least 1 selected from the group consisting of an acrylic polymer, a methacrylic polymer, a novolac resin, polyhydroxystyrene, a polyimide precursor, polyimide, polyamide, polyester, cellulose, and polysiloxane.

8. The liquid crystal display element according to claim 7, wherein the liquid crystal alignment treatment agent contains a polyimide precursor obtained by a reaction of a diamine component containing a diamine having a side chain structure of the formula [4-1a ] or the formula [4-2a ] with a tetracarboxylic acid component or a polyimide obtained by imidizing the polyimide precursor.

9. The liquid crystal display element according to claim 8, wherein the diamine having a side chain structure of the formula [4-1a ] or the formula [4-2a ] is represented by the following formula [4a ],

X represents a structure of the formula [4-1a ] or the formula [4-2a ]; m represents an integer of 1 to 4.

10. The liquid crystal display element according to claim 8 or 9, wherein the tetracarboxylic acid component is a tetracarboxylic dianhydride represented by the following formula [5],

Z represents a structure selected from the following formulas [5a ] to [5l ],

Z1 to Z4 each represent a hydrogen atom, a methyl group, a chlorine atom or a benzene ring; z5 and Z6 each represent a hydrogen atom or a methyl group.

11. The liquid crystal display element according to claim 7, wherein the liquid crystal alignment treatment agent comprises a polysiloxane obtained by polycondensing an alkoxysilane of the formula [ A1] or a polysiloxane obtained by polycondensing an alkoxysilane of the formula [ A1] with an alkoxysilane of the formula [ A2] and/or the formula [ A3],

(A)Si(A)(OA) [A1]

A1 represents the structure of the formula [4-1a ] or the formula [4-2a ]; a2 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; a3 represents an alkyl group having 1 to 5 carbon atoms; m represents an integer of 1 or 2; n represents an integer of 0 to 2; p represents an integer of 0 to 3; wherein m + n + p is 4,

(B)si(B)(OB) [A2]

B1 represents an organic group having 2 to 12 carbon atoms and containing at least 1 selected from a vinyl group, an epoxy group, an amino group, a mercapto group, an isocyanate group, a methacryloyl group, an acryloyl group, a ureido group and a cinnamoyl group; b2 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; b3 represents an alkyl group having 1 to 5 carbon atoms; m represents an integer of 1 or 2; n represents an integer of 0 to 2; p represents an integer of 0 to 3; wherein m + n + p is 4,

(D)Si(OD) [A3]

D1 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; d2 represents an alkyl group having 1 to 5 carbon atoms; n represents an integer of 0 to 3.

12. The liquid crystal display element according to any one of claims 6 to 11, wherein the liquid crystal alignment treatment agent comprises a compound having at least 1 structure selected from the following formulae [ b-1] to [ b-11],

BA represents a hydrogen atom or a benzene ring; BB to BD each represent an alkyl group having 1 to 5 carbon atoms.

13. The liquid crystal-represented element according to any one of claims 6 to 12, wherein the liquid crystal alignment treatment agent comprises a compound having at least 1 group selected from an epoxy group, an isocyanate group, an oxetanyl group, a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group, and a lower alkoxyalkyl group.

14. The liquid crystal display element according to any one of claims 6 to 13, wherein the liquid crystal alignment treatment agent contains at least 1 kind selected from the group consisting of 1-hexanol, cyclohexanol, 1, 2-ethylene glycol, 1, 2-propylene glycol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, dipropylene glycol dimethyl ether, cyclohexanone, cyclopentanone, and a solvent represented by any one of formulae [ D1] to [ D3],

D1 and D2 each represents an alkyl group having 1 to 3 carbon atoms; d3 represents an alkyl group having 1 to 4 carbon atoms.

15. The liquid crystal display element according to any one of claims 6 to 14, wherein the liquid crystal alignment treatment agent contains at least 1 selected from the group consisting of N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, and γ -butyrolactone.

16. The liquid crystal display element according to any one of claims 4 to 15, wherein the substrate is a plastic substrate.

Technical Field

The present invention relates to a novel compound, a liquid crystal composition containing the compound, and a transmission/scattering type liquid crystal display element obtained using the liquid crystal composition.

Background

Liquid crystal alignment elements of tn (twisted nematic) mode have been put into practical use. In this mode, a polarizing plate is used to switch light using the optical rotation characteristics of liquid crystal. If the polarizing plate is used, the light use efficiency is lowered. As a Liquid crystal display element not using a polarizing plate, an element using a polymer Dispersed Liquid crystal (also referred to as pdlc (polymer Dispersed Liquid crystal)) or a polymer Network Liquid crystal (also referred to as pnlc (polymer Network Liquid crystal)) which switches between a transmissive state (also referred to as a transparent state) and a scattering state of a Liquid crystal is known.

In these liquid crystal display elements, a liquid crystal composition containing a polymerizable compound that is polymerized by ultraviolet light is disposed between a pair of substrates having electrodes. By curing the liquid crystal composition by irradiation with ultraviolet rays, a composite of the liquid crystal and a cured product (for example, a polymer network) of the polymerizable compound can be formed. In such a liquid crystal display element, the transmissive state and the scattering state of the liquid crystal can be controlled by applying a voltage.

In a conventional liquid crystal display element using PDLC or PNLC, liquid crystal molecules are often in a turbid (scattering) state in a random direction when no voltage is applied, and in a transmissive state when a voltage is applied, liquid crystals are aligned in an electric field direction and transmit light (such a liquid crystal display element is also referred to as a normal (normal) type element). However, since the standard type element requires a constant voltage application to obtain a transmissive state, power consumption increases when the standard type element is used for applications in which the element is often used in a transparent state, for example, for window glass. On the other hand, a liquid crystal display element (also referred to as a reverse type element) using PDLC which exhibits a transmissive state when no voltage is applied and exhibits a scattering state when a voltage is applied has been proposed (see patent documents 1 and 2).

Disclosure of Invention

Problems to be solved by the invention

The polymerizable compound in the liquid crystal composition has an action of forming a polymer network to obtain desired optical characteristics and an action of improving the adhesion between the liquid crystal layer (the composite of the liquid crystal and the cured product of the polymerizable compound) and the liquid crystal alignment film. The liquid crystal alignment film used in the reverse cell has a problem that the adhesiveness between the liquid crystal layer and the liquid crystal alignment film is low because the liquid crystal alignment film has high hydrophobicity for vertically aligning the liquid crystal. In order to improve the adhesion, it is necessary to make the polymer network denser, and therefore it is necessary to introduce a large amount of polymerizable compound into the liquid crystal composition of the reverse type cell. However, when the polymer network is made dense, the vertical alignment of the liquid crystal is inhibited, and the transparency of the reverse type element when no voltage is applied and the scattering property when a voltage is applied are deteriorated. Therefore, it is necessary to improve the vertical alignment property of the liquid crystal when forming a liquid crystal layer for the polymerizable compound in the liquid crystal composition used for the reverse type device.

further, since the reverse type element is used by being stuck to a window glass of an automobile or a building in some cases, it is necessary that the vertical alignment property of the liquid crystal is not lowered and the adhesion between the liquid crystal layer and the liquid crystal alignment film is high even if the reverse type element is exposed to a severe environment of high temperature and high humidity and light irradiation for a long time. Heretofore, a liquid crystal display element satisfying this condition has not been found.

The invention aims to provide a liquid crystal display element which has high vertical alignment property of liquid crystal, good optical properties, namely good transparency when no voltage is applied and good scattering property when voltage is applied, has high adhesion between a liquid crystal layer and a liquid crystal alignment film, and can maintain the properties even when exposed to high temperature, high humidity and light irradiation environment for a long time.

Means for solving the problems

The present inventors have conducted extensive studies to achieve the above object, and as a result, have completed the present invention having the following gist.

That is, the present invention is directed to the following 1 to 16 liquid crystal compositions that can be used for liquid crystal display elements.

1. A compound represented by the following formula [1a ] (hereinafter also referred to as a specific compound).

T1 represents a structure selected from the following formulas [2-1a ] to [2-7a ]. T2 represents a linear or branched alkylene group having 2 to 18 carbon atoms, and any-CH 2-in the alkylene groups not adjacent to T1 and T3 is optionally replaced by-O-, -CO-, -COO-, -OCO-, -CONH-, -NHCO-, -NH-, a benzene ring or a cyclohexane ring. T3 represents a structure selected from the following formulae [1-1b ] to [1-4b ]. T4 represents a single bond or an alkylene group having 1 to 24 carbon atoms, and any of the aforementioned alkylene groups which are not adjacent to T3-CH 2-is optionally replaced by-O-, -CO-, -COO-, -OCO-, -CONH-, -NHCO-, -NH-, -CON (CH3) -, -S-or-SO 2-. T5 represents a 2-valent cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, or a 2-valent organic group having 17 to 51 carbon atoms and having a steroid skeleton, wherein any hydrogen atom in the cyclic group is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms or a fluorine atom. T6 represents a single bond, -O-, -OCH2-, -CH2O-, -COO-or-OCO-. T7 represents a cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, and any hydrogen atom in these cyclic groups is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms or a fluorine atom. T8 represents an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy group having 1 to 18 carbon atoms. mT represents an integer of 1 to 4. nT represents an integer of 0 to 4.

WA represents a hydrogen atom or a benzene ring.

TB represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

2. The compound according to 1, wherein the compound of the formula [1a ] is represented by the following formula [1b ] or formula [1c ].

T9, T11, T17 and T19 each represent a structure selected from the group consisting of the above-mentioned formulas [2-1a ] to [2-7a ]. T10 and T18 each represents a linear or branched alkylene group having 2 to 12 carbon atoms. T12 and T20 represent structures selected from the group consisting of the above-mentioned formulas [1-1b ] to [1-4b ]. T13 and T21 each represents a single bond or an alkylene group having 1 to 8 carbon atoms. T14 and T15 represent a benzene ring or a cyclohexane ring. T16 represents an alkyl or alkoxy group having 1 to 12 carbon atoms. T22 represents a C17-51 organic group having a steroid skeleton and a valence of 2. pT represents an integer of 0 to 4.

3. a liquid crystal composition comprising at least 1 compound selected from the group consisting of the compounds represented by the above formulae [1a ], [1b ] and [1c ].

4. A liquid crystal display element comprising a liquid crystal layer obtained by curing a liquid crystal composition containing a liquid crystal and a polymerizable compound, which is disposed between 1 pair of substrates provided with electrodes, by irradiating the composition with ultraviolet light, wherein at least one surface of the substrates is provided with a liquid crystal alignment film capable of vertically aligning the liquid crystal, and the liquid crystal composition contains at least 1 compound selected from the group consisting of the compounds represented by the above formulae [1a ], [1b ] and [1c ].

5. The liquid crystal display element according to claim 4, wherein the liquid crystal composition contains a compound represented by the following formula [2a ].

W1 represents a structure selected from the following formulas [2-1a ] to [2-7a ]. W2 represents a single bond, -O-, -COO-or-OCO-. W3 represents a single bond or an alkylene group having 1 to 12 carbon atoms. W4 represents a single bond, -O-, -COO-or-OCO-. W5 represents a benzene ring, a cyclohexane ring or a C17-51 organic group having a steroid skeleton. W6 represents a single bond, -CH2-, -CH2O-, -OCH2-, -O-, -COO-, -OCO-, -NHCO-or-CONH-. W7 represents a benzene ring or a cyclohexane ring. W8 represents an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy group having 1 to 18 carbon atoms. mW represents an integer of 0 to 4.

WA represents a hydrogen atom or a benzene ring.

6. The liquid crystal display element according to 4 or 5, wherein the liquid crystal alignment film is obtained from a liquid crystal alignment treatment agent containing a polymer having a side chain structure represented by the following formula [4-1a ] or formula [4-2a ].

x1 and X3 each represent a single bond, - (CH2) a- (a is an integer of 1 to 15), -O-, -CH2O-, -COO-or-OCO-. X2 represents a single bond or- (CH2) b- (b is an integer of 1 to 15). X4 represents a 2-valent cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, or a 2-valent organic group having 17 to 51 carbon atoms and having a steroid skeleton, wherein any hydrogen atom in the cyclic group is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms or a fluorine atom. X5 represents at least 1 cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, and any hydrogen atom on the cyclic groups is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms or a fluorine atom. X6 represents an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy group having 1 to 18 carbon atoms. n represents an integer of 0 to 4.

-X-X [4-2a]

X7 represents a single bond, -O-, -CH2O-, -CONH-, -NHCO-, -CON (CH3) -, -N (CH3) CO-, -COO-or-OCO-. X8 represents an alkyl group having 8 to 18 carbon atoms or a fluoroalkyl group having 6 to 18 carbon atoms.

7. The liquid crystal display element according to claim 6, wherein the liquid crystal alignment treatment agent contains at least 1 selected from the group consisting of an acrylic polymer, a methacrylic polymer, a novolac resin, polyhydroxystyrene, a polyimide precursor, polyimide, polyamide, polyester, cellulose, and polysiloxane.

8. The liquid crystal display element according to claim 7, wherein the liquid crystal alignment treatment agent contains a polyimide precursor obtained by a reaction of a diamine component containing a diamine having a side chain structure of the formula [4-1a ] or the formula [4-2a ] with a tetracarboxylic acid component, or a polyimide obtained by imidizing the polyimide precursor.

9. The liquid crystal display element according to claim 8, wherein the diamine having a side chain structure of the formula [4-1a ] or the formula [4-2a ] is represented by the following formula [4a ].

X represents a structure of the above formula [4-1a ] or formula [4-2a ]. m represents an integer of 1 to 4.

10. The liquid crystal display element according to 8 or 9, wherein the tetracarboxylic acid component is a tetracarboxylic dianhydride represented by the following formula [5 ].

Z represents a structure selected from the following formulas [5a ] to [5l ].

Z1 to Z4 each represent a hydrogen atom, a methyl group, a chlorine atom or a benzene ring. Z5 and Z6 each represent a hydrogen atom or a methyl group.

11. The liquid crystal display element according to claim 7, wherein the liquid crystal alignment treatment agent contains a polysiloxane obtained by polycondensing an alkoxysilane represented by the following formula [ A1] or a polysiloxane obtained by polycondensing an alkoxysilane represented by the following formula [ A1] with an alkoxysilane represented by the following formula [ A2] and/or formula [ A3 ].

(A)Si(A)(OA) [A1]

A1 represents the structure of the above formula [4-1a ] or formula [4-2a ]. A2 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. A3 represents an alkyl group having 1 to 5 carbon atoms. m represents an integer of 1 or 2. n represents an integer of 0 to 2. p represents an integer of 0 to 3. Wherein m + n + p is 4.

(B)Si(B)(OB) [A2]

B1 represents an organic group having 2 to 12 carbon atoms and containing at least 1 selected from a vinyl group, an epoxy group, an amino group, a mercapto group, an isocyanate group, a methacryloyl group, an acryloyl group, a ureido group and a cinnamoyl group. B2 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. B3 represents an alkyl group having 1 to 5 carbon atoms. m represents an integer of 1 or 2. n represents an integer of 0 to 2. p represents an integer of 0 to 3. Wherein m + n + p is 4.

(D)Si(OD) [A3]

D1 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. D2 represents an alkyl group having 1 to 5 carbon atoms. n represents an integer of 0 to 3.

12. The liquid crystal display element according to any one of claims 6 to 11, wherein the liquid crystal alignment treatment agent contains a compound having at least 1 structure selected from the following formulae [ b-1] to [ b-11 ].

BA represents a hydrogen atom or a benzene ring. BB to BD each represent an alkyl group having 1 to 5 carbon atoms.

13. The liquid crystal display element according to any one of claims 6 to 12, wherein the liquid crystal alignment treatment agent contains a compound having at least 1 group selected from an epoxy group, an isocyanate group, an oxetanyl group, a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group, and a lower alkoxyalkyl group.

14. The liquid crystal display element according to any one of claims 6 to 13, wherein the liquid crystal alignment treatment agent contains at least 1 kind selected from the group consisting of 1-hexanol, cyclohexanol, 1, 2-ethylene glycol, 1, 2-propylene glycol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, dipropylene glycol dimethyl ether, cyclohexanone, cyclopentanone, and a solvent represented by any one of formulae [ D1] to [ D3 ].

D1 and D2 each represents an alkyl group having 1 to 3 carbon atoms. D3 represents an alkyl group having 1 to 4 carbon atoms.

15. The liquid crystal display element according to any one of claims 6 to 14, wherein the liquid crystal alignment treatment agent contains at least 1 selected from the group consisting of N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, and γ -butyrolactone.

16. The liquid crystal display element according to any one of claims 4 to 15, wherein the substrate is a plastic substrate.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a liquid crystal display element can be obtained which has good optical properties, i.e., good transparency when no voltage is applied and good scattering properties when a voltage is applied, has high adhesion between a liquid crystal layer and a liquid crystal alignment film, and can maintain these properties even when exposed to an environment of high temperature, high humidity, or light irradiation for a long period of time. Therefore, the liquid crystal display element of the present invention can be used as a reverse type element for a liquid crystal display for display purposes, a light control window for controlling transmission and shielding of light, a light shutter element, and the like.

Detailed Description

< specific Compound liquid Crystal composition >

The specific compound is a compound represented by the formula [1a ]. Wherein T1 to T8, mT, and nT are as defined above, and among them, the following options are preferred.

T1 is preferably represented by the formulae [2-1a ] to [2-4a ] from the viewpoint of adhesion between a liquid crystal layer of a liquid crystal display element and a liquid crystal alignment film. More preferably, it is represented by the formula [2-1a ] or the formula [2-2a ]. T2 is preferably a linear or branched alkylene group having 2 to 12 carbon atoms, and any-CH 2-in the alkylene groups not adjacent to T1 and T3 is optionally replaced by-O-, -CO-, -COO-, -OCO-, -CONH-, -NHCO-, or-NH-. More preferably a linear or branched alkylene group having 2 to 8 carbon atoms. T3 is preferably represented by the formula [1-1b ], the formula [1-2b ] or the formula [1-4b ] from the viewpoint of optical characteristics of the liquid crystal display element. More preferably a formula [1-1b ] or a formula [1-2b ].

T4 is preferably a single bond or an alkylene group having 1 to 12 carbon atoms, and any of the aforementioned alkylene groups which are not adjacent to T3-CH 2-is optionally replaced by-O-, -CO-, -COO-, -OCO-, -CONH-, -NHCO-, -NH-, -CON (CH3) -, -S-or-SO 2-. More preferably a single bond or an alkylene group having 1 to 8 carbon atoms. T5 is preferably a benzene ring, a cyclohexane ring, or a C17-51 valent organic group having a steroid skeleton, from the viewpoint of optical characteristics of the liquid crystal display element. T6 is preferably a single bond, -O-, -COO-or-OCO-. More preferably a single bond. T7 is preferably a benzene ring or a cyclohexane ring from the viewpoint of optical characteristics of the liquid crystal display element.

T8 is preferably an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms or an alkoxy group having 1 to 18 carbon atoms from the viewpoint of optical characteristics of the liquid crystal display element. More preferably an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. mT is preferably 2 to 4 from the viewpoint of adhesion between a liquid crystal layer of the liquid crystal display element and the liquid crystal alignment film. More preferably 2. nT is preferably 0 to 3. More preferably 0 to 2.

the method for synthesizing the specific compound is not particularly limited, and can be synthesized, for example, by heating an isocyanate compound represented by the following formula [ TA ] and compounds represented by the following formulae [ TA-1] to [ TA-5] in the presence of a basic catalyst.

t1 and T2 are as defined in formula [1a ].

T4 to T8 and nT are as defined in the formula [1a ]. Ta represents an alkyl group having 1 to 3 carbon atoms.

The specific compound is preferably a compound represented by the following formula [1b ] or formula [1c ].

T9, T11, T17 and T19 represent the structures of the formulae [2-1a ] to [2-7a ], respectively. Among them, from the viewpoint of adhesion between the liquid crystal layer of the liquid crystal display element and the liquid crystal alignment film, the formulae [2-1a ] to [2-4a ] are preferable. More preferably, it is represented by the formula [2-1a ] or the formula [2-2a ]. T10 and T18 each represents a linear or branched alkylene group having 2 to 12 carbon atoms. Among them, a linear or branched alkylene group having 2 to 8 carbon atoms is preferable.

T12 and T20 represent the structures of the formulae [1-1b ] to [1-4b ]. Among them, the formula [1-1b ], the formula [1-2b ] or the formula [1-4b ] is preferable from the viewpoint of optical characteristics of the liquid crystal display element. More preferably a formula [1-1b ] or a formula [1-2b ]. T13 and T21 each represents a single bond or an alkylene group having 1 to 8 carbon atoms. T14 and T15 each represent a benzene ring or a cyclohexane ring.

T16 represents an alkyl or alkoxy group having 1 to 12 carbon atoms. Among them, from the viewpoint of optical characteristics of the liquid crystal display element, an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, or an alkoxy group having 1 to 18 carbon atoms is preferable. More preferably an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. T22 represents a C17-51 organic group having a steroid skeleton and a valence of 2. pT represents an integer of 0 to 4. Among them, 0 to 3 is preferable. More preferably 0 to 2.

Specific examples of the specific compounds of the formulae [1b ] and [1c ] include the following formulae [1a-1] to [1a-16], and these compounds are preferably used.

TA represents a structure selected from the group consisting of formulas [1-1b ] to [1-4b ]. TB represents a single bond, -O-, -COO-or-OCO-. TC represents an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. p1 and p2 each represents an integer of 0 to 7, and p1+ p2 each represents an integer of 1 to 7. p3 represents an integer of 0 to 8. p4 represents an integer of 0 to 2. p5, p6 and p7 each represent an integer of 0 to 6, and p5+ p6+ p7 represents an integer of 1 to 6.

TD represents a structure selected from the group consisting of formulas [1-1b ] to [1-4b ]. TE represents a single bond, -O-, -COO-or-OCO-. TF represents a single bond, -CH2-, -O-, -COO-or-OCO-. TG represents an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. p8 and p9 each represents an integer of 0 to 7, and p8+ p9 each represents an integer of 1 to 7. p10 represents an integer of 0 to 8. p11, p12 and p13 each represent an integer of 0 to 6, and p11+ p12+ p13 represents an integer of 1 to 6.

TH represents a structure selected from the group consisting of formulas [1-1b ] to [1-4b ]. TI represents a single bond, -O-, -COO-or-OCO-. p14 and p15 each represent an integer of 0 to 7, and p14+ p15 each represent an integer of 1 to 7. p16 represents an integer of 0 to 8. p17, p18 and p19 each represent an integer of 0 to 6, and p17+ p18+ p19 represents an integer of 1 to 6.

Specific examples of the specific compounds of the formula [1b ] and the formula [1c ] are more preferably those of the formula [1a-5], the formula [1a-7], the formula [1a-11] and the formula [1a-15 ]. From the viewpoint of optical characteristics of the liquid crystal display element, the formula [1a-5], the formula [1a-7] or the formula [1a-15] is particularly preferable.

The proportion of the specific compound is preferably 1 to 40 parts by mass relative to 100 parts by mass of the liquid crystal in the liquid crystal composition, from the viewpoint of optical characteristics of the liquid crystal display element. More preferably 1 to 30 parts by mass. Particularly preferably 1 to 15 parts by mass. The specific compound may be used in 1 kind or 2 or more kinds in combination depending on each property. The specific compound of the present invention can be used not only as a component of the liquid crystal composition of the liquid crystal display element of the present invention but also as a component of a liquid crystal composition of a liquid crystal display element other than the liquid crystal display element.

The liquid crystal composition used in the liquid crystal display element of the present invention contains a liquid crystal, a polymerizable compound, and the specific compound of the formula [1a ]. The liquid crystal may use nematic liquid crystal, smectic liquid crystal, or cholesteric liquid crystal. Among them, liquid crystals having negative dielectric anisotropy are preferable. In addition, from the viewpoint of low-voltage driving and scattering characteristics, liquid crystals having large anisotropy of dielectric constant and large anisotropy of refractive index are preferable. In addition, in the liquid crystal, 2 or more kinds of liquid crystals can be used according to the above-described respective physical property values of the phase transition temperature, the dielectric anisotropy, and the refractive index anisotropy.

In order to drive a liquid crystal display element as an active element such as a tft (thin Film transistor), the liquid crystal is required to have high resistance and high voltage holding ratio (also referred to as VHR). Therefore, as the liquid crystal, fluorine-based or chlorine-based liquid crystals having high resistance and whose VHR is not lowered by active energy rays such as ultraviolet rays are preferable.

In the liquid crystal display element, a dichroic dye may be dissolved in a liquid crystal composition to form a guest-host type element. In this case, an element which is transparent when no voltage is applied and which absorbs (scatters) when a voltage is applied can be obtained. In this liquid crystal display element, the direction of the director (direction of alignment) of the liquid crystal changes by 90 degrees depending on the presence or absence of an applied voltage. Therefore, by utilizing the difference in the light absorption characteristics of the dichroic dye, a high contrast can be obtained as compared with a conventional guest-host type element in which switching is performed between random alignment and vertical alignment. In the guest-host type element in which the dichroic dye is dissolved, the liquid crystal becomes colored when it is aligned in the horizontal direction, and becomes opaque only in the scattering state. Therefore, an element which is switched from colorless transparency when no voltage is applied to colored opaque state or colored transparent state with the application of voltage can be obtained.

In order to form the polymer network, a polymerizable compound may be introduced into the liquid crystal composition, and a polymerization reaction may be performed by irradiating ultraviolet rays when manufacturing the liquid crystal display element, or a polymer obtained by previously polymerizing a polymerizable compound may be introduced into the liquid crystal composition. In the case where a polymer is formed, it is also necessary to have a site where a polymerization reaction occurs by irradiation with ultraviolet rays. From the viewpoint of the operability of the liquid crystal composition, that is, the suppression of the increase in viscosity of the liquid crystal composition and the solubility in liquid crystal, it is preferable to introduce a polymerizable compound into the liquid crystal composition and to cause a polymerization reaction to form a polymer network by irradiating ultraviolet rays at the time of producing a device.

The polymerizable compound in the liquid crystal composition is not particularly limited as long as it is dissolved in the liquid crystal, but when the polymerizable compound is dissolved in the liquid crystal, a temperature at which a part or the whole of the liquid crystal composition is in a liquid crystal phase needs to be present. When a part of the liquid crystal composition is in a liquid crystal phase, the liquid crystal display element may be visually confirmed, and substantially uniform transparency and scattering characteristics may be obtained in the entire element.

The polymerizable compound may be a compound that is polymerized by ultraviolet light, and in this case, the polymerization may be advanced in any reaction form to form a polymer network. Specific reaction forms include radical polymerization, cationic polymerization, anionic polymerization, and addition polymerization. Among them, radical polymerization is preferred as a reaction form of the polymerizable compound from the viewpoint of optical characteristics of the liquid crystal display element. In this case, the following radical type polymerizable compound or oligomer thereof can be used as the polymerizable compound. As described above, a polymer obtained by polymerizing these polymerizable compounds may be used.

Specific examples of the radical polymerizable compound or oligomer thereof include radical polymerizable compounds described in International patent publication No. 2015/146987 (published as 2015.10.1) on pages 69 to 71. The amount of the radical polymerizable compound or oligomer thereof is preferably 70 to 120 parts by mass based on 100 parts by mass of the liquid crystal in the liquid crystal composition, from the viewpoint of adhesion between the liquid crystal layer of the liquid crystal display element and the liquid crystal alignment film. More preferably 80 to 110 parts by mass. These radical polymerizable compounds may be used in 1 kind or in a mixture of 2 or more kinds depending on the characteristics.

In order to promote the formation of the polymer network, it is preferable to introduce a radical initiator (also referred to as a polymerization initiator) that generates radicals by ultraviolet rays into the liquid crystal composition for the purpose of promoting radical polymerization of the polymerizable compound. Specifically, the radical initiator is described in International patent publication No. 2015/146987 (publication No. 2015.10.1) at pages 71 to 72. The amount of the radical initiator is preferably 0.01 to 10 parts by mass per 100 parts by mass of the liquid crystal in the liquid crystal composition, from the viewpoint of adhesion between the liquid crystal layer of the liquid crystal display element and the liquid crystal alignment film. More preferably 0.05 to 5 parts by mass. The radical initiator may be used in 1 kind or 2 or more kinds in combination depending on the characteristics.

In order to improve the optical properties, particularly the transparency, of the liquid crystal display element, it is preferable to introduce a compound represented by the following formula [2a ] (also referred to as an additive compound) into the liquid crystal composition used for the liquid crystal display element of the present invention. In particular, it is preferably used together with a specific compound.

W1 represents a structure selected from the following formulas [2-1a ] to [2-7a ]. W2 represents a single bond, -O-, -COO-or-OCO-. W3 represents a single bond or an alkylene group having 1 to 12 carbon atoms. W4 represents a single bond, -O-, -COO-or-OCO-. W5 represents a benzene ring, a cyclohexane ring or a C17-51 organic group having a steroid skeleton. W6 represents a single bond, -CH2-, -CH2O-, -OCH2-, -O-, -COO-, -OCO-, -NHCO-or-CONH-. W7 represents a benzene ring or a cyclohexane ring. W8 represents an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy group having 1 to 18 carbon atoms. mW represents an integer of 0 to 4.

WA represents a hydrogen atom or a benzene ring.

More specifically, the compounds represented by the formula [2a ] include compounds represented by the following formulae [2a-1] to [2a-6], and these compounds are preferably used from the viewpoint of optical characteristics of the liquid crystal display element.

WA represents a single bond, -O-, -COO-or-OCO-. WB represents an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. p1 represents an integer of 1 to 8. p2 represents an integer of 0 to 2.

WC represents a single bond, -O-, -COO-or-OCO-. WD represents a single bond, -CH2-, -O-, -COO-or-OCO-. WE represents an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. p3 represents an integer of 1 to 8.

WF represents a single bond, -O-, -COO-or-OCO-. p4 represents an integer of 0 to 8.

Among the compounds represented by the formula [2a ], preferred is a compound represented by the formula [2a-1], the formula [2a-2], the formula [2a-7] or the formula [2a-8] from the viewpoint of optical characteristics of the liquid crystal display element. More preferably formula [2a-1] or formula [2a-2 ].

The proportion of the additive compound is preferably 1 to 30 parts by mass relative to 100 parts by mass of the liquid crystal in the liquid crystal composition, from the viewpoint of optical characteristics of the liquid crystal display element. More preferably 1 to 20 parts by mass, and most preferably 1 to 15 parts by mass. The additive compound may be used in 1 kind or in combination of 2 or more kinds depending on the characteristics.

< Polymer >

The liquid crystal alignment film in the liquid crystal display element of the present invention is preferably a liquid crystal alignment film obtained from a liquid crystal alignment treatment agent containing a polymer having a specific side chain structure represented by the following formula [4-1a ] or formula [4-2a ].

X1 represents a single bond, - (CH2) a- (a is an integer of 1 to 15), -O-, -CH2O-, -COO-or-OCO-. Among them, a single bond, - (CH2) a- (a is an integer of 1 to 15), - (O) -, -CH2O-, or-COO-is preferable from the viewpoint of availability of raw materials and ease of synthesis. More preferably a single bond, - (CH2) a- (a is an integer of 1 to 10), -O-, -CH 2O-or-COO-. X2 represents a single bond or- (CH2) b- (b is an integer of 1 to 15). Among them, a single bond or- (CH2) b- (b is an integer of 1 to 10) is preferable.

X3 represents a single bond, - (CH2) a- (a is an integer of 1 to 15), -O-, -CH2O-, -COO-or-OCO-. Among them, a single bond, - (CH2) a- (a is an integer of 1 to 15), -O-, -CH 2O-or-COO-is preferable from the viewpoint of ease of synthesis. More preferably a single bond, - (CH2) a- (a is an integer of 1 to 10), -O-, -CH 2O-or-COO-. X4 represents a 2-valent cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, or a 2-valent organic group having 17 to 51 carbon atoms and having a steroid skeleton, wherein any hydrogen atom in the cyclic group is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms or a fluorine atom. Among them, a benzene ring, a cyclohexane ring, or an organic group having 17 to 51 carbon atoms and having a steroid skeleton is preferable from the viewpoint of ease of synthesis.

X5 represents a cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, and any hydrogen atom in these cyclic groups is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms or a fluorine atom. Among them, preferred is a benzene ring or a cyclohexane ring.

x6 represents an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy group having 1 to 18 carbon atoms. Among them, preferred is an alkyl group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluorinated alkoxy group having 1 to 10 carbon atoms. More preferably an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. Particularly preferably an alkyl group having 1 to 9 carbon atoms or an alkoxy group having 1 to 9 carbon atoms. n represents an integer of 0 to 4. Among them, from the viewpoint of availability of raw materials and ease of synthesis, 0 to 3 is preferable. More preferably 0 to 2.

Preferable combinations of X1 to X6 and n include the same combinations as (2-1) to (2-629) described in tables 6 to 47 on pages 13 to 34 of International publication WO2011/132751 (published 2011.10.27). In the tables of the international publications, X1 to X6 in the present invention are represented as Y1 to Y6, and Y1 to Y6 are alternatively understood as X1 to X6. In addition, (2-605) to (2-629) described in each table of the international publication, the organic group having 17 to 51 carbon atoms of the steroid skeleton in the present invention is an organic group having 12 to 25 carbon atoms of the steroid skeleton, and the organic group having 12 to 25 carbon atoms of the steroid skeleton may be alternatively understood as an organic group having 17 to 51 carbon atoms of the steroid skeleton.

Among them, preferred is a combination of (2-25) to (2-96), (2-145) to (2-168), (2-217) to (2-240), (2-268) to (2-315), (2-364) to (2-387), (2-436) to (2-483), or (2-603) to (2-615). More preferred is a combination of (2-49) to (2-96), (2-145) to (2-168), (2-217) to (2-240), (2-603) to (2-606), (2-607) to (2-609), (2-611), (2-612), or (2-624).

-X-X [4-2a]

X7 represents a single bond, -O-, -CH2O-, -CONH-, -NHCO-, -CON (CH3) -, -N (CH3) CO-, -COO-or-OCO-. Among them, a single bond, -O-, -CH2O-, -CONH-, -CON (CH3) -or-COO-is preferable. More preferably a single bond, -O-, -CONH-or-COO-. X8 represents an alkyl group having 8 to 18 carbon atoms or a fluoroalkyl group having 6 to 18 carbon atoms. Among them, an alkyl group having 8 to 18 carbon atoms is preferable.

As described above, the specific side chain structure in the present invention is preferably represented by the formula [4-1a ] from the viewpoint of obtaining a high and stable vertical alignment property of liquid crystal.

The specific polymer having a specific side chain structure is not particularly limited, and is preferably at least one polymer selected from the group consisting of an acrylic polymer, a methacrylic polymer, a novolac resin, polyhydroxystyrene, a polyimide precursor, polyimide, polyamide, polyester, cellulose, and polysiloxane. More preferably a polyimide precursor, polyimide or polysiloxane. When a polyimide precursor or a polyimide (also collectively referred to as a polyimide-based polymer) is used as the specific polymer, it is preferably a polyimide precursor or a polyimide obtained by reacting a diamine component with a tetracarboxylic acid component.

The polyimide precursor has a structure represented by the following formula [ A ].

R1 represents a 4-valent organic group. R2 represents a 2-valent organic group. A1 and A2 each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. A3 and A4 each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an acetyl group. n represents a positive integer.

The diamine component is a diamine having 2 primary or secondary amino groups in the molecule. Examples of the tetracarboxylic acid component include a tetracarboxylic acid compound, a tetracarboxylic acid dianhydride, a tetracarboxylic acid dihalide compound, a tetracarboxylic acid dialkyl ester compound, or a tetracarboxylic acid dialkyl ester dihalide compound.

The polyimide-based polymer is preferably a polyamic acid having a structural formula of a repeating unit represented by the following formula [ D ] or a polyimide obtained by imidizing the polyamic acid, because the polyimide can be obtained relatively easily from a tetracarboxylic dianhydride represented by the following formula [ B ] and a diamine represented by the following formula [ C ].

R1 and R2 are the same as defined in the formula [ A ].

R1 and R2 are the same as defined in the formula [ A ].

In addition, the polymer of the formula [ D ] obtained above may be introduced with an alkyl group having 1 to 8 carbon atoms of A1 and A2 in the formula [ A ], an alkyl group having 1 to 5 carbon atoms of A3 and A4 in the formula [ A ] or an acetyl group by a usual synthesis method. .

< specific side chain type diamine >

As a method for introducing a specific side chain structure into a polyimide-based polymer, a diamine having a specific side chain structure is preferably used as a part of the raw material. Particularly, a diamine represented by the following formula [4a ] (also referred to as a specific side chain type diamine) is preferably used.

X represents a structure of the above formula [4-1a ] or formula [4-2a ]. Further, specific contents and preferred combinations of X1, X2, X3, X4, X5, X6, and n in the formula [4-1a ] are as described in the aforementioned formula [4-1a ], and specific contents and preferred combinations of X7 and X8 in the formula [4-2a ] are as described in the aforementioned formula [4-2a ]. m represents an integer of 1 to 4. Among them, 1 is preferable. In the present invention, as described above, it is preferable to use a specific side chain type diamine having a specific side chain structure of the formula [4-1a ] from the viewpoint of the vertical alignment property of the liquid crystal.

Specific examples of the specific side chain type diamine having a specific side chain structure of the formula [4-1a ] include diamine compounds of the formulae [2-1] to [2-6] and the formulae [2-9] to [2-36] described in the international publication WO2013/125595 (publication 2013.8.29) at pages 15 to 19. In the description of International publication WO2013/125595, R2 in the formulae [2-1] to [2-3] and R4 in the formulae [2-4] to [2-6] represent an alkyl group having 1 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy group having 1 to 18 carbon atoms. A4 in the formula [2-13] represents a linear or branched alkyl group having 3 to 18 carbon atoms. R3 in the formulae [2-4] to [2-6] represents-O-, -CH2O-, -COO-or-OCO-.

Among them, preferred diamines are those represented by the formulae [2-1] to [2-6], the formulae [2-9] to [2-13] or the formulae [2-22] to [2-31] described in International publication WO 2013/125595. From the viewpoint of optical characteristics of the liquid crystal display element, diamines of the following formulae [4a-32] to [4a-41] are more preferable.

R1 and R2 each represents an alkyl group having 3 to 12 carbon atoms.

R3 and R4 represent alkyl groups having 3 to 12 carbon atoms, and cis-trans isomerization of 1, 4-cyclohexylene is trans isomer.

Particularly preferred are diamines of formulae [4a-35] to [4a-37], formulae [4a-40] and formulae [4a-41] from the viewpoint of optical characteristics of the liquid crystal display element.

Specific examples of the specific side chain type diamine having a specific side chain structure of the formula [4-2a ] include diamine compounds of the formulae [ DA1] to [ DA11] described in International publication WO2013/125595 (publication 2013.8.29) page 23. In the description of International publication WO2013/125595, A1 in the formulae [ DA1] to [ DA5] represents an alkyl group having 8 to 22 carbon atoms or a fluoroalkyl group having 6 to 18 carbon atoms.

The ratio of the specific side chain diamine used is preferably 10 to 80 mol% based on the diamine component as a whole, from the viewpoint of optical properties of the liquid crystal display element and adhesion between the liquid crystal layer and the liquid crystal alignment film. More preferably 20 to 70 mol%. The specific side chain type diamine may be used in 1 kind or 2 or more kinds in combination depending on the respective properties.

< diamine of No. 2 >

The diamine component used for producing the polyimide-based polymer preferably contains a diamine represented by the following formula [4b ] (also referred to as a2 nd diamine).

Y1 represents a single bond, -O-, -NH-, -N (CH3) -, -CH2O-, -CONH-, -NHCO-, -CON (CH3) -, -N (CH3) CO-, -COO-or-OCO-. Among them, a single bond, -O-, -CH2O-, -CONH-, -COO-or-OCO-is preferable. From the viewpoint of availability of raw materials and ease of synthesis, a single bond, -O-, -CH 2O-or-COO-is more preferable.

Y2 represents a single bond, an alkylene group having 1 to 18 carbon atoms, or an organic group having 6 to 24 carbon atoms and having a cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle, wherein any hydrogen atom in the cyclic group is optionally substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms or a fluorine atom. Among them, a single bond, an alkylene group having 1 to 12 carbon atoms, a benzene ring or a cyclohexane ring is preferable. The liquid crystal layer is more preferably a single bond or an alkylene group having 1 to 12 carbon atoms, from the viewpoint of adhesion between the liquid crystal layer and the liquid crystal alignment film.

Y3 represents a single bond, -O-, -NH-, -N (CH3) -, -CH2O-, -CONH-, -NHCO-, -CON (CH3) -, -N (CH3) CO-, -COO-or-OCO-. Among them, a single bond, -O-, -COO-or-OCO-is preferable. More preferably a single bond or-OCO-. Y4 represents a structure selected from the following formulae [4b-a ] to [4b-i ], preferably from [4b-a ] to [4b-f ]. Among them, the formulae [4b-a ] to [4b-e ] are preferable. More preferred is the formula [4b-a ], the formula [4b-b ], the formula [4b-d ] or the formula [4b-e ] from the viewpoint of adhesion between the liquid crystal layer and the liquid crystal alignment film.

YA represents a hydrogen atom or a benzene ring. m represents an integer of 1 to 4. Among them, 1 or 2 is preferable. n represents an integer of 1 to 4. Among them, 1 is preferable.

Specific examples of the 2 nd type diamine include the following formulas [4b-1] to [4b-12], and these examples are preferably used.

n1 represents an integer of 2 to 12.

n2 represents an integer of 0 to 12. n3 represents an integer of 2 to 12.

Specific examples of the 2 nd type diamine are preferably represented by the formula [4b-1], the formula [4b-2], the formula [4b-5] to the formula [4b-7], the formula [4b-11] or the formula [4b-12 ]. More preferably, the compound is represented by any one of the formulae [4b-5] to [4b-7], [4b-11] or [4b-12 ].

The use ratio of the 2 nd type diamine is preferably 10 to 70 mol%, more preferably 20 to 60 mol%, based on the diamine component as a whole, from the viewpoint of optical characteristics of the liquid crystal display element and adhesion between the liquid crystal layer and the liquid crystal alignment film. The 2 nd diamine may be used in 1 kind or 2 or more kinds in combination depending on the characteristics.

< diamine of No. 3 >

The diamine component used for producing the polyimide-based polymer also preferably contains a diamine represented by the following formula [4c ] (also referred to as 3 rd diamine).

W represents a structure selected from the following formulas [4c-a ] to [4c-d ]. m represents an integer of 1 to 4. Among them, 1 is preferable.

a represents an integer of 0 to 4. Among them, from the viewpoint of availability of raw materials and ease of synthesis, 0 or 1 is preferable. b represents an integer of 0 to 4. Among them, from the viewpoint of availability of raw materials and ease of synthesis, 0 or 1 is preferable. WA and WB each represent an alkyl group having 1 to 12 carbon atoms. WC represents an alkyl group having 1 to 5 carbon atoms.

Specific examples of the 3 rd diamine include the following. For example, 2, 4-dimethyl-m-phenylenediamine, 2, 6-diaminotoluene, 2, 4-diaminophenol, 3, 5-diaminobenzyl alcohol, 2, 4-diaminobenzyl alcohol, 4, 6-diaminoresorcinol, 2, 4-diaminobenzoic acid, 2, 5-diaminobenzoic acid, 3, 5-diaminobenzoic acid. In addition, diamines of the following formulae [4c-1] and [4c-2] are exemplified.

As specific examples of the 3 rd diamine, among them, 2, 4-diaminophenol, 3, 5-diaminobenzyl alcohol, 2, 4-diaminobenzyl alcohol, 4, 6-diaminoresorcinol, 2, 4-diaminobenzoic acid, 2, 5-diaminobenzoic acid, 3, 5-diaminobenzoic acid, diamines of the formula [4c-1] or the formula [4c-2] are preferable. From the viewpoint of solubility of the polyimide polymer in a solvent and optical characteristics of the liquid crystal display element, 2, 4-diaminophenol, 3, 5-diaminobenzyl alcohol, 3, 5-diaminobenzoic acid, or formula [2a-1] are more preferable.

As the diamine component used for producing the polyimide-based polymer, diamines other than the aforementioned diamines (also referred to as other diamines) may be used. Specifically, there are mentioned other diamine compounds described in International patent publication WO2015/012368 (publication 2015.1.29) at pages 27 to 30 and diamine compounds of the formulae [ DA1] to [ DA14] described at pages 30 to 32 of the above publication. Further, other diamines may be used in 1 kind or in combination of 2 or more kinds depending on the characteristics.

< tetracarboxylic acid component >

As the tetracarboxylic acid component used for producing the polyimide-based polymer, a tetracarboxylic dianhydride represented by the following formula [5], a tetracarboxylic acid dihalide compound, a tetracarboxylic acid dialkyl ester compound or a tetracarboxylic acid dialkyl ester dihalide compound as a tetracarboxylic acid derivative thereof (all of which are also collectively referred to as a specific tetracarboxylic acid component.) are preferably used.

Z represents a structure selected from the following formulas [5a ] to [5l ].

Z1 to Z4 each represent a hydrogen atom, a methyl group, a chlorine atom or a benzene ring. Z5 and Z6 each represent a hydrogen atom or a methyl group.

Among them, Z in the formula [5] is preferably represented by the formula [5a ], the formula [5c ], the formula [5d ], the formula [5e ], the formula [5f ], the formula [5g ], the formula [5k ] or the formula [5l ] from the viewpoint of ease of synthesis and ease of polymerization reaction in producing a polymer. More preferably, the compound is represented by the formula [5a ], the formula [5e ], the formula [5f ], the formula [5g ], the formula [5k ] or the formula [5l ]. From the viewpoint of optical characteristics of the liquid crystal display element, the formula [5a ], the formula [5e ], the formula [5f ], the formula [5g ] or the formula [5l ] is particularly preferable.

The ratio of the specific tetracarboxylic acid component is preferably 1 mol% or more based on the total tetracarboxylic acid component. More preferably 5 mol% or more. Particularly preferably 10 mol% or more. From the viewpoint of optical characteristics of the liquid crystal display element, the molar ratio is most preferably 10 to 90 mol%.

The polyimide-based polymer may contain a tetracarboxylic acid component other than the specific tetracarboxylic acid component within a range not impairing the effects of the present invention. Examples of the other tetracarboxylic acid component include tetracarboxylic acid compounds shown below, tetracarboxylic dianhydrides, dicarboxylic acid dihalide compounds, dicarboxylic acid dialkyl esters, or dialkyl ester dihalide compounds.

Specifically, other tetracarboxylic acid components described in International patent publication WO2015/012368 (published 2015.1.29) at pages 34 to 35 can be mentioned. The specific tetracarboxylic acid component and the other tetracarboxylic acid components may be used in 1 kind or in combination of 2 or more kinds depending on the characteristics. The method for synthesizing the polyimide-based polymer is not particularly limited. Usually, the diamine component is reacted with a tetracarboxylic acid component. Specifically, the method described in International patent application publication WO2015/012368 (published 2015.1.29) on pages 35 to 36 can be mentioned.

< polyimide-based Polymer and production thereof >

The reaction of the diamine component and the tetracarboxylic acid component is usually carried out in a solvent containing the diamine component and the tetracarboxylic acid component. The solvent used in this case is not particularly limited as long as the polyimide precursor formed is dissolved. Specific examples thereof include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ -butyrolactone, N-dimethylformamide, N-dimethylacetamide, dimethylsulfoxide, and 1, 3-dimethyl-imidazolidinone. When the polyimide precursor has high solubility in a solvent, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or a solvent represented by any one of the following formulae [ D1] to [ D3] may be used.

D1 and D2 each represents an alkyl group having 1 to 3 carbon atoms. D3 represents an alkyl group having 1 to 4 carbon atoms. Further, they may be used alone or in combination. Further, even in the case of a solvent which does not dissolve the polyimide precursor, the solvent may be mixed and used within a range where the produced polyimide precursor is not precipitated. Further, the organic solvent is preferably dehydrated and dried for use because moisture in the organic solvent inhibits the polymerization reaction and causes hydrolysis of the polyimide precursor to be produced.

The polyimide is obtained by ring-closing a polyimide precursor, and the ring-closing ratio of the amic acid group (also referred to as imidization ratio) in this polyimide is not necessarily 100%, and can be arbitrarily adjusted depending on the application and purpose. Among them, from the viewpoint of solubility of the polyimide polymer in a solvent, 30 to 80% is preferable. More preferably 40 to 70%.

The molecular weight of the polyimide-based polymer is preferably 5000 to 1000000, more preferably 10000 to 150000, in terms of the strength of the liquid crystal alignment film obtained therefrom, the workability in forming the liquid crystal alignment film, and the film coatability, as measured by GPC (Gel Permeation Chromatography).

< production of siloxane-based Polymer >

when a polysiloxane is used as the specific polymer, it is preferable to use a polysiloxane obtained by polycondensation of an alkoxysilane represented by the following formula [ a1], or a polysiloxane (also collectively referred to as a polysiloxane polymer) obtained by polycondensation of an alkoxysilane represented by the following formula [ a1] and an alkoxysilane represented by the following formula [ a2] and/or formula [ A3 ].

An alkoxysilane of the formula [ A1 ]:

(A)Si(A)(OA) [A1]

A1 represents the structure of the above formula [4-1a ] or formula [4-2a ]. Further, specific contents and preferable combinations of X1, X2, X3, X4, X5, X6 and n in the formula [4-1a ] are as described in the aforementioned formula [4-1a ], and specific contents and preferable combinations of X7 and X8 in the formula [4-2a ] are as described in the aforementioned formula [4-2a ]. Among them, the structure of the formula [4-1a ] is preferable from the viewpoint of obtaining a high and stable vertical alignment property of liquid crystal. A2 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Among them, hydrogen atom or alkyl group having 1 to 3 carbon atoms is preferable. A3 represents an alkyl group having 1 to 5 carbon atoms. Among them, an alkyl group having 1 to 3 carbon atoms is preferable from the viewpoint of reactivity of the polycondensation.

m represents an integer of 1 or 2. Among them, 1 is preferable from the viewpoint of ease of synthesis. n represents an integer of 0 to 2. p represents an integer of 0 to 3. Among them, from the viewpoint of reactivity of polycondensation, 1 to 3 is preferable. More preferably 2 or 3. m + n + p is 4.

Specific examples of the alkoxysilane of the formula [ A1] include alkoxysilanes of the formulae [2a-1] to [2a-32] described in International patent publication WO2015/008846(2015.1.22 publication) at pages 17 to 21. Among them, alkoxysilanes of the formulae [2a-9] to [2a-21], [2a-25] to [2a-28] or [2a-32] in the above publication are preferable. The alkoxysilane of the formula [ A1] may be used in 1 kind or in a mixture of 2 or more kinds depending on the characteristics.

An alkoxysilane of the formula [ A2 ]:

(B)Si(B)(OB) [A2]

B1 represents an organic group having 2 to 12 carbon atoms and containing at least 1 selected from a vinyl group, an epoxy group, an amino group, a mercapto group, an isocyanate group, a methacryloyl group, an acryloyl group, a ureido group and a cinnamoyl group. Among them, from the viewpoint of ease of obtaining, an organic group having a vinyl group, an epoxy group, an amino group, a methacryloyl group, an acryloyl group, or a ureido group is preferable. More preferably an organic group having a methacryloyl group, an acryloyl group or a ureido group. B2 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Among them, hydrogen atom or alkyl group having 1 to 3 carbon atoms is preferable. B3 represents an alkyl group having 1 to 5 carbon atoms. Among them, an alkyl group having 1 to 3 carbon atoms is preferable from the viewpoint of reactivity of the polycondensation.

m represents an integer of 1 or 2. Among them, 1 is preferable from the viewpoint of ease of synthesis. n represents an integer of 0 to 2. p represents an integer of 0 to 3. Among them, from the viewpoint of reactivity of polycondensation, 1 to 3 is preferable. More preferably 2 or 3. m + n + p is 4.

Specific examples of the alkoxysilane of the formula [ A2] include alkoxysilanes of the formula [2b ] described in International patent publication WO2015/008846 (2015.1.22), pages 21 to 24. Among them, preferred is allyltriethoxysilane, allyltrimethoxysilane, diethoxymethylvinylsilane, dimethoxymethylvinylsilane, triethoxyvinylsilane, vinyltrimethoxysilane, vinyltris (2-methoxyethoxy) silane, 3- (triethoxysilyl) propyl methacrylate, 3- (trimethoxysilyl) propyl acrylate, 3- (trimethoxysilyl) propyl methacrylate, 3- (trimethoxysilyl) propyl 3-glycidoxypropyl (dimethoxy) methylsilane, 3-glycidoxypropyl (diethoxy) methylsilane, 3-glycidoxypropyltrimethoxysilane or 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane. The alkoxysilane of the formula [ A2] may be used in 1 kind or in a mixture of 2 or more kinds depending on the characteristics.

An alkoxysilane of the formula [ A3 ]:

(D)Si(OD) [A3]

D1 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Among them, hydrogen atom or alkyl group having 1 to 3 carbon atoms is preferable. D2 represents an alkyl group having 1 to 5 carbon atoms. Among them, an alkyl group having 1 to 3 carbon atoms is preferable from the viewpoint of reactivity of the polycondensation. n represents an integer of 0 to 3.

Specific examples of the alkoxysilane of the formula [ A3] include alkoxysilanes of the formula [2c ] described in International patent publication WO2015/008846(2015.1.22 publication) at pages 24 to 25.

In the formula [ A3], examples of the alkoxysilane in which n is 0 include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane and tetrabutoxysilane. As the alkoxysilane of the formula [ A3], it is preferable to use these alkoxysilanes. The alkoxysilane of the formula [ A3] may be used in 1 kind or in a mixture of 2 or more kinds depending on the characteristics.

The polysiloxane polymer is a polysiloxane obtained by polycondensing an alkoxysilane of the formula [ A1] or a polysiloxane obtained by polycondensing an alkoxysilane of the formula [ A1] with an alkoxysilane of the formula [ A2] and/or the formula [ A3 ]. That is, the polysiloxane polymer is any of a polysiloxane obtained by polycondensing only an alkoxysilane of the formula [ a1], a polysiloxane obtained by polycondensing 2 alkoxysilanes of the formulae [ a1] and [ a2], a polysiloxane obtained by polycondensing 2 alkoxysilanes of the formulae [ a1] and [ A3], and a polysiloxane obtained by polycondensing 3 alkoxysilanes of the formulae [ a1], [ a2], and [ A3 ].

Among them, from the viewpoint of reactivity of polycondensation and solubility of the polysiloxane polymer in a solvent, a polysiloxane obtained by polycondensation of a plurality of kinds of alkoxysilanes is preferable. That is, it is preferable to use any of polysiloxanes obtained by polycondensing 2 kinds of alkoxysilanes of the formulae [ A1] and [ A2], polysiloxanes obtained by polycondensing 2 kinds of alkoxysilanes of the formulae [ A1] and [ A3], and polysiloxanes obtained by polycondensing 3 kinds of alkoxysilanes of the formulae [ A1], [ A2], and [ A3 ].

when a plurality of alkoxysilanes are used in the preparation of the polysiloxane polymer, the alkoxysilane of the formula [ a1] is used in an amount of preferably 1 to 40 mol%, more preferably 1 to 30 mol%, based on the total amount of the alkoxysilanes. The ratio of the alkoxysilane of the formula [ a2] to be used is preferably 1 to 70 mol%, more preferably 1 to 60 mol%, based on the total amount of the alkoxysilanes. Further, the ratio of the alkoxysilane of the formula [ a3] used is preferably 1 to 99 mol%, more preferably 1 to 80 mol%, of all alkoxysilanes.

The method of polycondensing the polysiloxane polymer is not particularly limited. Specifically, the method described in International patent application publication WO2015/008846 (published 2015.1.22) on pages 26 to 29 can be mentioned.

In the polycondensation reaction for producing the polysiloxane polymer, when a plurality of alkoxysilanes of the formula [ A1], the formula [ A2] or the formula [ A3] are used, the reaction may be carried out using a mixture obtained by mixing a plurality of alkoxysilanes in advance, or may be carried out while adding a plurality of alkoxysilanes in sequence.

In the present invention, the solution of the polysiloxane polymer obtained by the above-mentioned method may be used as it is as a specific composition, or the solution of the polysiloxane polymer obtained by the above-mentioned method may be concentrated, diluted with a solvent or replaced with another solvent as necessary to be used as a specific polymer.

The solvent used for dilution (also referred to as an addition solvent) may be a solvent used in the polycondensation reaction or other solvents. The solvent to be added is not particularly limited as long as the polysiloxane polymer is uniformly dissolved, and 1 or 2 or more kinds thereof can be arbitrarily selected. Examples of the solvent to be added include, in addition to the solvents used in the above-mentioned polycondensation reaction, ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, ester solvents such as methyl acetate, ethyl acetate, and ethyl lactate, and the like.

When the polysiloxane polymer and the other polymer are used as the specific polymer, it is preferable that the alcohol generated in the polycondensation reaction of the polysiloxane polymer is distilled off under normal pressure or reduced pressure before the polysiloxane polymer is mixed with the other polymer.

< liquid Crystal alignment treatment agent >

The liquid crystal aligning agent of the present invention is a solution for forming a liquid crystal alignment film, and preferably a solution containing a specific polymer having a specific side chain structure of the above formula [4-1a ] or formula [4-2a ] and a solvent. All of the polymer components in the liquid crystal alignment treatment agent may be a specific polymer, or a polymer other than the specific polymer may be mixed. In this case, the content of the polymer other than the above is 0.5 to 15 parts by mass, preferably 1 to 10 parts by mass, based on 100 parts by mass of the specific polymer. As the polymer other than these, the aforementioned polymers having no specific side chain structure of the formula [4-1a ] or the formula [4-2a ] can be exemplified.

The content of the solvent in the liquid crystal aligning agent can be appropriately selected from the viewpoint of the method of applying the liquid crystal aligning agent and obtaining a desired film thickness. Among them, the solvent content in the liquid crystal alignment treatment agent is preferably 50 to 99.9 mass% from the viewpoint of forming a uniform vertical liquid crystal alignment film by coating. More preferably 60 to 99% by mass. Particularly preferably 65 to 99 mass%.

< solvent >

the solvent used in the liquid crystal aligning agent is not particularly limited as long as it dissolves the specific polymer. Among them, when the specific polymer is a polyimide precursor, polyimide, polyamide or polyester, or when the solubility of an acrylic polymer, methacrylic polymer, novolac resin, polyhydroxystyrene, cellulose or polysiloxane in a solvent is low, it is preferable to use the solvent (also referred to as solvent a).

examples thereof include N, N-dimethylformamide, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ -butyrolactone, 1, 3-dimethyl-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, and 4-hydroxy-4-methyl-2-pentanone. Among them, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ -butyrolactone is preferably used. These solvents may be used alone or in combination.

When the specific polymer is an acrylic polymer, a methacrylic polymer, a novolac resin, polyhydroxystyrene, cellulose, or polysiloxane, and further when the specific polymer is a polyimide precursor, polyimide, polyamide, or polyester, and the solubility of these specific polymers in a solvent is high, the following solvents (also referred to as solvents B.) can be used.

Specific examples of the solvent B include those described in International patent publication WO2014/171493 (publication 2014.10.23) at pages 58 to 60. Among them, 1-hexanol, cyclohexanol, 1, 2-ethylene glycol, 1, 2-propylene glycol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, dipropylene glycol dimethyl ether, cyclohexanone, cyclopentanone, or a solvent of the formula [ D1] to [ D3] is preferably used.

When these solvents B are used, it is preferable to use N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ -butyrolactone in combination with the solvents A in order to improve the coatability of the liquid crystal alignment treatment agent. More preferably, gamma-butyrolactone is used in combination.

These solvents B can improve the film coatability and surface smoothness of the liquid crystal alignment film when the liquid crystal alignment treatment agent is applied, and therefore, when a polyimide precursor, a polyimide, a polyamide or a polyester is used as the specific polymer, it is preferable to use them in combination with the above-mentioned solvents a. In this case, the solvent B is preferably 1 to 99% by mass of the entire solvent contained in the liquid crystal aligning agent. Among them, 10 to 99% by mass is preferable. More preferably 20 to 95 mass%.

< specific Compound A >

From the viewpoint of optical characteristics of the liquid crystal display element, it is preferable to introduce a compound having at least 1 structure selected from the following formulae [ b-1] to [ b-11] (also referred to as a specific compound a.) into the liquid crystal aligning agent.

BA represents a hydrogen atom or a benzene ring. BB to BD represent an alkyl group having 1 to 5 carbon atoms.

Specific examples of the specific compound A include the following formulae [ b-1a ] to [ b-24a ], and these compounds are preferably used.

k1 represents an integer of 1 to 12. Among them, 1 to 8 are preferable from the viewpoint of optical characteristics of the liquid crystal display element. k2 represents an integer of 0 to 4. Among them, 1 or 2 is preferable from the viewpoint of optical characteristics of the liquid crystal display element. Ka represents a single bond, -O-, -CH2O-, -CONH-, -NHCO-, -CON (CH3) -, -N (CH3) CO-, -COO-or-OCO-. Among them, from the viewpoint of availability of raw materials and ease of synthesis, -O-or-COO-is preferred.

Kb represents an alkyl group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluorinated alkoxy group having 1 to 18 carbon atoms. Among them, preferred is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. More preferably an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms.

k3 represents an integer of 1 to 12. Among them, 1 to 8 are preferable from the viewpoint of optical characteristics of the liquid crystal display element. Kc represents a single bond, - (CH2) c- (c is an integer of 1 to 15), -O-, -CH2O-, -COO-or-OCO-. Among them, preferred is-COO-or-OCO-from the viewpoint of availability of raw materials and ease of synthesis. Kd represents a single bond, -O-, -CH2O-, -CONH-, -NHCO-, -CON (CH3) -, -N (CH3) CO-, -COO-or-OCO-. Among them, from the viewpoint of availability of raw materials and ease of synthesis, -O-or-COO-is preferred.

Ke represents an alkyl group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluorinated alkoxy group having 1 to 18 carbon atoms. Among them, preferred is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. More preferably an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms.

k4 represents an integer of 0 to 4. Among them, 1 or 2 is preferable from the viewpoint of optical characteristics of the liquid crystal display element. Kf represents an alkyl group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluorinated alkoxy group having 1 to 18 carbon atoms. Among them, preferred is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. More preferably an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms.

k5 represents an integer of 1 to 12. Among them, 1 to 8 are preferable from the viewpoint of optical characteristics of the liquid crystal display element. k6 represents an integer of 0 to 4. Among them, 1 or 2 is preferable from the viewpoint of optical characteristics of the liquid crystal display element. Kg represents an alkyl group having 1 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluoroalkoxy group having 1 to 18 carbon atoms. Among them, preferred is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. More preferably an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms.

Kh represents a single bond, - (CH2) c- (c is an integer of 1 to 15), -O-, -CH2O-, -COO-or-OCO-. Among them, preferred is-COO-or-OCO-from the viewpoint of availability of raw materials and ease of synthesis. Ki represents an alkyl group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluorinated alkoxy group having 1 to 18 carbon atoms. Among them, preferred is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. More preferably an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms.

k7 represents an integer of 1 to 12. Among them, 1 to 8 are preferable from the viewpoint of optical characteristics of the liquid crystal display element. Kj represents a single bond, - (CH2) c- (c is an integer of 1 to 15), -O-, -CH2O-, -COO-or-OCO-. Among them, preferred is-COO-or-OCO-from the viewpoint of availability of raw materials and ease of synthesis.

Kk represents an alkyl group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluorinated alkoxy group having 1 to 18 carbon atoms. Among them, preferred is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. More preferably an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms.

As specific examples of the specific compound A, among them, preferred is a compound of the formula [ b-1a ], the formula [ b-2a ], the formula [ b-7a ], the formula [ b-8a ], the formula [ b-10a ], the formula [ b-11a ], the formula [ b-13a ], the formula [ b-14a ], the formula [ b-16a ] or the formula [ b-17a ].

The amount of the specific compound a used in the liquid crystal aligning agent is preferably 0.1 to 30 parts by mass per 100 parts by mass of the specific polymer, from the viewpoint of optical characteristics of the liquid crystal display device. More preferably 0.5 to 20 parts by mass. Particularly preferably 1 to 10 parts by mass. The specific compound a may be used in a mixture of 1 or 2 or more depending on the characteristics.

< specific crosslinkable Compound >

In order to improve the film strength of the resin film, it is preferable to introduce a compound having at least 1 group selected from an epoxy group, an isocyanate group, an oxetanyl group, a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group, and a lower alkoxyalkyl group (also collectively referred to as a specific crosslinkable compound) into the liquid crystal aligning agent. In this case, it is necessary to have 2 or more of these groups in the compound.

Specific examples of the crosslinkable compound having an epoxy group or an isocyanate group include crosslinkable compounds having an epoxy group or an isocyanate group described in International publication WO2014/171493 (publication 2014.10.23) pages 63 to 64.

Specific examples of the crosslinkable compound having an oxetanyl group include crosslinkable compounds of the formulae [4a ] to [4k ] described in International patent publication WO2011/132751(2011.10.27 publication) at pages 58 to 59.

Specific examples of the crosslinkable compound having a cyclocarbonate group include crosslinkable compounds of the formulae [5-1] to [5-42] described in International patent publication WO2012/014898 (publication 2012.2.2) at pages 76 to 82.

Specific examples of the crosslinkable compound having a hydroxyl group, a hydroxyalkyl group and a lower alkoxyalkyl group include melamine derivatives and benzoguanamine derivatives described in International publication No. 2014/171493 (publication No. 2014.10.23) at pages 65 to 66, and crosslinkable compounds of formulae [6-1] to [6-48] described in International publication No. WO2011/132751 (publication No. 2011.10.27) at pages 62 to 66.

The content of the specific crosslinkable compound in the liquid crystal aligning agent is preferably 0.1 to 100 parts by mass per 100 parts by mass of the total polymer components. In order to promote the crosslinking reaction and to exhibit the desired effect, it is more preferably 0.1 to 50 parts by mass per 100 parts by mass of the total polymer components. Particularly preferably 1 to 30 parts by mass.

< specific Generator >

It is preferable to introduce at least 1 kind of generator (also referred to as a specific generator) selected from a photoradical generator, a photoacid generator, and a photobase generator into the liquid crystal alignment treatment agent. Specific examples of the specific propellant include those described in International patent publication No. 2014/171493 (publication No. 2014.10.23) at pages 54 to 56. Among them, the specific generator is preferably a photo radical generator from the viewpoint of adhesion between the liquid crystal layer of the liquid crystal display element and the liquid crystal alignment film.

< specific adhesion Compound >

In order to improve the adhesion between the liquid crystal layer of the liquid crystal display element and the vertical liquid crystal alignment film, it is preferable to introduce a compound having at least 1 structure selected from the following formulae [ e-1] to [ e-8] (also referred to as a specific adhesion compound) into the liquid crystal alignment treatment agent.

EA represents a hydrogen atom or a benzene ring. EB represents at least 1 cyclic group selected from a benzene ring, a cyclohexane ring and a heterocycle. EC represents an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms or a fluorine-containing alkoxy group having 1 to 18 carbon atoms.

Specific examples of the specific adhesion compounds include compounds of the formula [6] described in International patent publication WO2015/012368(2015.1.29 publication) at pages 43 to 46. Further, an adhesive compound described in International publication WO2014/171493 (publication 2014.10.23) on pages 61 to 63 can be used.

The content of the specific adhesion compound in the liquid crystal aligning agent is preferably 0.1 to 150 parts by mass with respect to 100 parts by mass of the total polymer components. In order to promote the crosslinking reaction and to exhibit the desired effect, it is more preferably 0.1 to 100 parts by mass per 100 parts by mass of the total polymer components. Particularly preferably 1 to 50 parts by mass.

In order to promote charge transfer in the liquid crystal alignment film and to promote element charge removal, a nitrogen-containing heterocyclic amine compound represented by the formulae [ M1] to [ M156] described in International publication WO2011/132751 (published 2011.10.27) on pages 69 to 73 may be added to the liquid crystal alignment agent. The amine compound may be added directly to the liquid crystal aligning agent, or may be added after being dissolved in an appropriate solvent to a concentration of 0.1 to 10% by mass, preferably 1 to 7% by mass. The solvent is not particularly limited as long as it is an organic solvent that dissolves the specific polymer.

< Compound for improving film thickness uniformity and surface smoothness of liquid Crystal alignment film >

The liquid crystal aligning agent may be a compound which improves the uniformity of the thickness and surface smoothness of the liquid crystal alignment film when the liquid crystal aligning agent is applied thereto, within a range not impairing the effects of the present invention. Further, a compound or the like which improves the adhesion between the liquid crystal alignment film and the substrate may be used.

Examples of the compound for improving the film thickness uniformity and surface smoothness of the liquid crystal alignment film include a fluorine-based surfactant, a silicone-based surfactant, and a nonionic surfactant. Specifically, a surfactant described in International publication WO2014/171493 (publication 2014.10.23) page 67 can be mentioned. The amount of the polymer is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass, per 100 parts by mass of the total polymer components contained in the liquid crystal aligning agent.

Specific examples of the compound for improving the adhesion between the liquid crystal alignment film and the substrate include compounds described in International publication WO2014/171493 (publication 2014.10.23) pages 67 to 69. The amount of the polymer is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, per 100 parts by mass of the total polymer components contained in the liquid crystal aligning agent. In addition to the above, a dielectric or conductive material for changing electrical characteristics such as permittivity and conductivity of the liquid crystal alignment film may be added to the liquid crystal alignment agent.

< method for manufacturing liquid crystal alignment film and liquid crystal display element

The substrate used in the liquid crystal display element is not particularly limited as long as it is a substrate having high transparency, and a plastic substrate such as an acrylic substrate, a polycarbonate substrate, a PET (polyethylene terephthalate) substrate, or the like, and a film thereof may be used in addition to the glass substrate. When the element is made into a reverse type element and used for a light control window or the like, a plastic substrate or a film is preferable. In addition, from the viewpoint of simplifying the process, it is preferable to use a substrate on which an ito (indium Tin oxide) electrode, an izo (indium Zinc oxide) electrode, an igzo (indium Gallium nitride) electrode, an organic conductive film, and the like for driving liquid crystal are formed. In the case of a reflection-type reverse type device, a substrate formed with a dielectric multilayer film of a metal such as silicon wafer or aluminum can be used as long as it is a single-sided substrate.

In the liquid crystal display element, at least one side of a substrate has a liquid crystal alignment film for vertically aligning liquid crystal molecules. The liquid crystal alignment film can be obtained by applying a liquid crystal alignment treatment agent to a substrate, baking the applied liquid crystal alignment treatment agent, and then performing alignment treatment such as brushing treatment or light irradiation. The liquid crystal alignment film of the present invention may be used without performing such alignment treatment. The method of applying the liquid crystal alignment treatment agent is not particularly limited, and there are industrial fields such as screen printing, offset printing, flexographic printing, ink jet method, dipping method, roll coating method, slit coating method, spin coating method, and spray method, and it can be appropriately selected depending on the kind of substrate and the target film thickness of the liquid crystal alignment film.

After the liquid crystal alignment treatment agent is coated on the substrate, the solvent is evaporated at a temperature of 30 to 300 ℃, preferably 30 to 250 ℃ depending on the kind of the substrate and the solvent used in the liquid crystal alignment treatment agent by a heating means such as a hot plate, a thermal cycle oven, or an IR (infrared ray) oven, thereby forming a liquid crystal alignment film. In particular, when a plastic substrate is used as the substrate, the substrate is preferably treated at a temperature of 30 to 150 ℃.

When the thickness of the liquid crystal alignment film after firing is too large, it is disadvantageous in terms of power consumption of the liquid crystal display element, and when the thickness is too small, reliability of the element may be lowered, and therefore, it is preferable to be 5 to 500 nm. More preferably 10 to 300nm, and particularly preferably 10 to 250 nm. The liquid crystal composition used for the liquid crystal display element is the liquid crystal composition described above, but a spacer for controlling an electrode gap (also referred to as a gap) of the liquid crystal display element may be introduced thereto.

The method of injecting the liquid crystal composition is not particularly limited, and examples thereof include the following methods. That is, when a glass substrate is used as the substrate, the following methods can be used: a pair of substrates on which liquid crystal alignment films were formed were prepared, a sealant was applied to all but a part of 4 sides of one substrate, and then the other substrate was attached with the surface of the liquid crystal alignment film facing inward, thereby producing an empty cell. Then, the liquid crystal composition was injected under reduced pressure from a portion where the sealant was not applied, thereby obtaining a liquid crystal composition injection cell. When a plastic substrate or film is used as the substrate, the following methods can be mentioned: a pair of substrates on which liquid crystal alignment films are formed are prepared, a liquid crystal composition is dropped on one substrate by an odf (one Drop filling) method, an ink jet method, or the like, and then the other substrate is bonded to obtain a liquid crystal composition injection unit. In the liquid crystal display element of the present invention, since the liquid crystal layer has high adhesion to the liquid crystal alignment film, the sealant may not be applied to the 4 sides of the substrate.

The gap of the liquid crystal display element can be controlled by the aforementioned spacer or the like. The method includes: as described above, a method of introducing a spacer of a target size into a liquid crystal composition, a method of using a substrate having a column spacer of a target size, and the like can be used. In addition, when the substrates are bonded by lamination using a plastic or film substrate, the gap can be controlled without introducing a spacer.

The gap of the liquid crystal display element is preferably 1 to 100 μm, more preferably 1 to 50 μm. Particularly preferably 2 to 30 μm. If the gap is too small, the contrast of the element decreases, and if the gap is too large, the driving voltage of the element increases.

The liquid crystal display element of the present invention is obtained by curing a liquid crystal composition in a state where a part or all of the liquid crystal composition exhibits liquid crystallinity to form a cured product composite (liquid crystal layer) of a liquid crystal and a polymerizable compound. The curing of the liquid crystal composition is performed by irradiating the liquid crystal composition injection unit with ultraviolet rays. Examples of the light source of the ultraviolet irradiation device used in this case include a metal halide lamp and a high-pressure mercury lamp. The wavelength of the ultraviolet ray is preferably 250 to 400 nm. Among them, the preferable range is 310 to 370 nm. After the irradiation with ultraviolet rays, heat treatment may be performed. The temperature is 40 to 120 ℃, preferably 40 to 80 ℃.