TWI676654B - Liquid crystal aligning agents containing polyamic acid or derivative thereof, liquid crystal alighment films and liquid crystal display devices - Google Patents

Abstract

The invention relates to a liquid crystal alignment agent, which contains: at least one polymer selected from the group consisting of polyamic acid and its derivatives; and selected from the group consisting of N-methyl-2-pyrrolidone, γ -The first solvent in the group consisting of butyrolactone, etc .; the first solvent selected from the group consisting of butyl cellosolve, 1-butoxy-2-propanol, diethylene glycol ethyl methyl ether, etc. A second solvent; a third solvent selected from the group consisting of diisobutyl ketone and dipentyl ether; a fourth solvent selected from the group consisting of compounds represented by the following formula (1).

In formula (1), when R ¹ is an alkyl group having ² carbon atoms, R ² is an alkyl group having 3 carbon atoms, and when R ¹ is an alkyl group having 4 carbon atoms, R ² is an alkyl group having 1 or 2 carbon atoms. base.

Description

Liquid crystal alignment agent containing polyamic acid or its derivative, liquid crystal alignment Film and liquid crystal display element

The present invention relates to a polyamic acid or a derivative thereof obtained using a tetracarboxylic dianhydride, a liquid crystal alignment agent containing a specific solvent, a liquid crystal alignment film formed using the liquid crystal alignment agent, and further including the liquid crystal alignment. Film liquid crystal display element. The term “liquid crystal alignment agent” in the present invention refers to a polymer-containing composition for forming a liquid crystal alignment film.

Various display devices such as monitors for personal computers, LCD TVs, viewfinders for cameras, projection displays, and other liquid-crystal display elements such as optical print heads, optical Fourier transform elements, and light valves, which are currently being manufactured and generally distributed. The mainstream is the display element using a nematic liquid crystal. The display mode of a nematic liquid crystal display element is well known as a twisted nematic (TN) mode and a super twisted nematic (STN) mode. In recent years, in order to improve the narrowness of the viewing angle, which is one of the problem points of these modes, a TN-type liquid crystal display element using an optical compensation film, and a technology that combines vertical alignment with a protruding structure have been proposed. A multi-domain vertical alignment (MVA) mode, or an in-plane switching (IPS) mode, a fringe field switching (FFS) mode of a lateral electric field method, and are practical.

The development of the technology of liquid crystal display elements is achieved not only by the improvement of these driving methods or the element structure, but also by the improvement of the constituent members used in the element. Among the constituent members used in the liquid crystal display element, particularly the liquid crystal alignment film is one of important materials related to display quality, and as the quality of the liquid crystal display element is improved, it is important to improve the performance of the alignment film.

The liquid crystal alignment film is formed using a liquid crystal alignment agent. Currently, the main liquid crystal alignment agents used are resins such as polyamic acid, polyimide, polyimide, polyimide, and polyamic acid esters, which are solutions in which these resins are dissolved in an organic solvent. (Varnish). After applying this solution on a substrate, a film is formed by a method such as heating to form a polyfluorene-based liquid crystal alignment film.

An alignment treatment method for regularly aligning liquid crystal molecules on the surface of a liquid crystal alignment film is widely used in industry as a rubbing method capable of performing simple and large-area high-speed processing. The rubbing method is a process of wiping a surface of a liquid crystal alignment film in one direction by using a cloth having fibers such as nylon, rayon, and polyester, thereby obtaining a uniform alignment of liquid crystal molecules. However, the following problems have been pointed out in the rubbing treatment: dust caused by the removal of the liquid crystal alignment film or damage caused by the liquid crystal alignment film, which reduces the display quality, and the generation of static electricity; Alignment processing method.

Attention as an alignment treatment method instead of a rubbing method is irradiation light The photo-alignment processing method to perform the alignment processing. The photo-alignment treatment method has proposed various alignment mechanisms such as a photodecomposition method, a photo-isomerization method, a photo-dimerization method, and a photo-crosslinking method (for example, refer to Non-Patent Document 1, Patent Document 1, and Patent Document 2). Compared with the rubbing method, the photo-alignment method has higher alignment uniformity, and because it is a non-contact alignment processing method, it does not damage the film, and it can reduce the display failure of liquid crystal display elements such as dust and static electricity. And other advantages.

In this case, the printing method of the alignment film includes a spin coating method, flexographic printing, inkjet printing, and the like. Among these printing methods, a method suitable for pattern printing is flexographic printing. This method is a method of transferring a varnish on an APR plate to a substrate, and it is difficult to cause unevenness in film thickness or disturbance of the linearity of the edge portion of the printed alignment film (hereinafter, sometimes referred to as “unevenness”). However, for printing on a large-area substrate of the sixth generation or more, inkjet printing is preferred.

However, if the varnish is ejected onto the substrate in the form of droplets using an inkjet method to form a coating film, there may be a problem that uneven stripes occur along the scanning direction of the ejection port (nozzle). It is generally believed that the cause of this unevenness in the stripe is: (1) the droplets are not sufficiently coated and diffused on the substrate; (2) the ejected droplets have poor leveling properties, and the solute component (solid content) is unevenly precipitated ); (3) A solvent having a good applicability dries quickly, and causes degradation of the applied solution during drying (for example, refer to Patent Document 3).

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 9-297313

[Patent Document 2] Japanese Patent Laid-Open No. 10-251646

[Patent Document 3] Japanese Patent Laid-Open No. 2009-063797

[Non-patent literature]

[Non-Patent Document 1] "Liquid Crystal" Vol. 3 No. 4 262, 1999

An object of the present invention is to provide a liquid crystal alignment agent capable of preventing unevenness of streaks of the coating film when the coating film for a liquid crystal alignment film is printed by an inkjet method, without causing shrinkage of the film or uneven edges. In addition, a liquid crystal alignment film formed using the liquid crystal alignment agent is provided, and a liquid crystal display element including the liquid crystal alignment film is further provided.

The present inventors have found a solvent capable of simultaneously preventing streaks, preventing shrinkage of the film, and unevenness of the edges by using a solvent of a plurality of components for a resin for forming an alignment film described later, and thus completed the present invention.

The present invention includes the following items.

[1] A liquid crystal alignment agent containing at least one polymer and a solvent selected from the group consisting of polyamic acid and its derivatives; and the solvent contains a solvent selected from N-methyl-2-pyrrolidine At least one of a group consisting of ketone, γ-butyrolactone, 1,3-dimethyl-2-imidazolidinone, and N-ethyl-2-pyrrolidone, as a first solvent, contains At least one of the group consisting of butyl cellosolve (BC), 1-butoxy-2-propanol, diethylene glycol ethyl methyl ether, and diethylene glycol propyl methyl ether is used as the first Two solvents containing at least one selected from the group consisting of diisobutyl ketone and dipentyl ether as the third solvent, and further containing a group selected from the group consisting of a compound represented by the following formula (1) At least one of them is used as the fourth solvent;

In formula (1), when R ¹ is an alkyl group having ² carbon atoms, R ² is an alkyl group having 3 carbon atoms, and when R ¹ is an alkyl group having 4 carbon atoms, R ² is an alkyl group having 1 or 2 carbon atoms. base.

[2] The liquid crystal alignment agent according to item [1], wherein the proportion of the first solvent is 20% to 89% by weight relative to the weight of the entire solvent, and the proportion of the second solvent is 10% by weight relative to the total weight of the solvent. % To 60% by weight, the ratio of the third solvent is 0.1% to 15% by weight with respect to the total solvent weight, and the ratio of the fourth solvent is 0.1% to 20% by weight relative to the total solvent weight.

[3] The liquid crystal alignment agent according to item [1] or [2], wherein the tetracarboxylic dianhydride used in the synthesis of the polymer contains a compound selected from the following formulae (AN-I) to (AN-VII) At least one of the group of compounds represented by); the diamine contains a diamine selected from the following formulae (DI-1) to (DI-16) without a side chain, and the following formula (DIH -1) to dihydrazide without side chains represented by formula (DIH-3) and diamines with side chains represented by formulas (DI-31) to (DI-35) below At least one of the group;

In formula (AN-I), formula (AN-IV) and formula (AN-V), X is independently a single bond or -CH _2- ; in formula (AN-II), G is a single bond and carbon number 1 ~ 20 alkylene, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- ; formula (AN-II) ~ formula In (AN-IV), Y is independently one selected from the group of a trivalent group described below, and the bond is connected to an arbitrary carbon. At least one hydrogen of the group may be methyl or ethyl Group or phenyl group;

In formulas (AN-III) to (AN-V), ring A ¹⁰ is a group of a monocyclic hydrocarbon having 3 to 10 carbons or a group of a condensing polycyclic hydrocarbon having 6 to 30 carbons. At least one hydrogen of the group may be substituted by methyl, ethyl, or phenyl, and the bonding bond hanging on the ring is linked to any carbon constituting the ring, and two bonding bonds may also be linked to the same carbon; the formula (AN -VI), X ¹⁰ is an alkylene group having 2 to 6 carbon atoms, Me represents a methyl group, and Ph represents a phenyl group; in the formula (AN-VII), G ^{10 is} independently -O-, -COO-, or- OCO-, r is independently 0 or 1;

In the formula (DI-1), G ²⁰ is -CH _2- , at least one -CH ₂ -may be substituted with -NH-, -O-, m is an integer from 1 to 12, and at least one hydrogen of alkylene is Can be replaced by -OH; in formula (DI-3) and formula (DI-5) to formula (DI-7), G ^{21 is} independently a single bond, -NH-, -NCH _3- , -O-,- S-, -SS-, -SO _2- , -CO-, -COO-, -CONCH _3- , -CONH-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -,-(CH ₂ ) _m- , -O- (CH ₂ ) _m -O-, -N (-Ra)-(CH ₂ ) _k -N (-Ra)-,-(OC ₂ H ₄ ) _m -O-,- O-CH ₂ -C (CF ₃ ) ₂ -CH ₂ -O-, -O-CO- (CH ₂ ) _m -CO-O-, -CO-O- (CH ₂ ) _m -O-CO-, -(CH ₂ ) _m -NH- (CH ₂ ) _m- , -CO- (CH ₂ ) _k -NH- (CH ₂ ) _k -,-(NH- (CH ₂ ) _m ) _k -NH-,- CO-C ₃ H _6- (NH-C ₃ H ₆ ) _n -CO- or -S- (CH ₂ ) _m -S-, Ra is an alkyl group having 1 to 3 carbon atoms, and m is independently 1 to 12 Is an integer of 1 to 5, and k is an integer of 1 or 2. In formula (DI-4), s is an integer of 0 to 2. In formula (DI-6) and formula (DI-7), G ^{22 is} independently a single bond, -O-, -S-, -CO-, -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -NH-, or an extension of 1 to 10 carbon atoms Alkyl group; at least one hydrogen of cyclohexane ring and benzene ring in formula (DI-2) to formula (DI-7) may pass -F, -Cl, alkyl group having 1 to 3 carbon atoms , -OCH ₃ , -OH, -CF ₃ , -CO ₂ H, -CONH ₂ , -NHC ₆ H ₅ , phenyl or benzyl. In addition, in formula (DI-4), the At least one hydrogen may be substituted with one selected from the group consisting of a group represented by the following formulae (DI-4-a) to (DI-4-e); the bonding position in the formula is A group that is not fixed on a carbon atom constituting a ring indicates that the bonding position in the ring is arbitrary; the bonding position of -NH ₂ on a cyclohexane ring or a benzene ring is a bond other than G ²¹ or G ²² Any position other than the position;

In formula (DI-4-a) and formula (DI-4-b), R ^{20 is} independently hydrogen or -CH ₃ ;

In formula (DI-11), r is 0 or 1; in formulas (DI-8) to (DI-11), the bonding position of -NH ₂ bonded to the ring is an arbitrary position;

In the formula (DI-12), R ²¹ and R ^{22 are} independently an alkyl group or a phenyl group having 1 to 3 carbon atoms, and G ^{23 is} independently an alkylene group, a phenylene group, or an alkyl group having 1 to 6 carbon atoms. Substituted phenyl group, w is an integer from 1 to 10; in formula (DI-13), R ^{23 is} independently an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms or -Cl, p Independently an integer of 0 to 3, q is an integer of 0 to 4; in formula (DI-14), ring B is a monocyclic heterocyclic aromatic group, and R ²⁴ is hydrogen, -F, -Cl, carbon 1 to 6 alkyl, alkoxy, vinyl, alkynyl, q is independently an integer of 0 to 4; in formula (DI-15), ring C is a heterocyclic aromatic group or heterocyclic aliphatic Group group; in the formula (DI-16), G ²⁴ is a single bond, an alkylene group having 2 to 6 carbon atoms or 1,4-phenylene group, and r is 0 or 1; A group that is not fixed on a carbon atom constituting a ring indicates that its bonding position in the ring is arbitrary; in formulas (DI-13) to (DI-16), a bond of -NH ₂ on the ring The knot position is arbitrary;

In formula (DIH-1), G ²⁵ is a single bond, an alkylene group having 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- ; In the formula (DIH-2), the ring D is a cyclohexane ring, a benzene ring or a naphthalene ring, and at least one hydrogen of the group may be substituted by a methyl group, an ethyl group or a phenyl group In formula (DIH-3), the ring E is independently a cyclohexane ring or a benzene ring, at least one hydrogen of the group may be substituted by a methyl group, an ethyl group, or a phenyl group, and Y is a single bond and a carbon number 1 to 20 alkylene, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- ; formula (DIH-2) and In formula (DIH-3), the bonding position of -CONHNH ₂ bonded to the ring is an arbitrary position;

In formula (DI-31), G ²⁶ is a single bond, -O-, -COO-, -OCO-, -CO-, -CONH-, -CH ₂ O-, -OCH _2- , -CF ₂ O- , -OCF ₂ -or-(CH ₂ ) _{m '} -, m' is an integer from 1 to 12; R ²⁵ is an alkyl group having 3 to 30 carbon atoms, a phenyl group, a group having a steroid skeleton, or the following formula A group represented by (DI-31-a). In the alkyl group, at least one hydrogen may be substituted by -F, and at least one -CH ₂ -may be substituted by -O-, -CH = CH-, or -C≡. Substituted by C-, the hydrogen of the phenyl group may be -F, -CH ₃ , -OCH ₃ , -OCH ₂ F, -OCHF ₂ , -OCF ₃ , alkyl group having 3 to 30 carbon atoms, or 3 to 30 carbon atoms. Substituted by alkoxy, the bonding position of -NH ₂ bonded to the benzene ring is indicated at any position in the ring,

In the formula (DI-31-a), G ²⁷ , G ²⁸ and G ²⁹ are bonding groups, and these groups are independently a single bond or an alkylene group having 1 to 12 carbon atoms. The above -CH ₂ -may be replaced by -O-, -COO-, -OCO-, -CONH-, -CH = CH-, and ring B ²¹ , ring B ²² , ring B ²³ and ring B ^{24 are} independently 1,4-phenylene, 1,4-cyclohexyl, 1,3-dioxane-2,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl, naphthalene At least one hydrogen of -1,5-diyl, naphthalene-2,7-diyl or anthracene-9,10-diyl, ring B ²¹ , ring B ²² , ring B ²³ and ring B ²⁴ may pass through -F Or -CH ₃ , and s, t, and u are independently integers of 0 to 2. The total of these is 1 to 5. When s, t, or u is 2, the two bonding groups in each bracket can be The same or different, and the two rings may be the same or different. R ²⁶ is hydrogen, -F, -OH, alkyl having 1 to 30 carbons, fluorine substituted alkyl having 1 to 30 carbons, carbon An alkoxy group having 1 to 30, -CN, -OCH ₂ F, -OCHF ₂ , or -OCF _3. At least one of the alkyl groups having 1 to 30 carbon atoms -CH ₂ -can be obtained by the following formula (DI- 31-b) is substituted by a divalent group represented by

In formula (DI-31-b), R ²⁷ and R ^{28 are} independently an alkyl group having 1 to 3 carbon atoms, and v is an integer of 1 to 6,

In formula (DI-32) and formula (DI-33), G ^{30 is} independently a single bond, -CO- or -CH _2- , R ^{29 is} independently hydrogen or -CH ₃ , and R ³⁰ is hydrogen and carbon number 1 to 20 alkyl groups, or alkenyl groups having 2 to 20 carbon atoms; at least one hydrogen of the benzene ring in formula (DI-33) may be substituted with 1 to 20 carbon groups or phenyl groups; the formula A group in which the bonding position in is not fixed to any carbon atom constituting the ring indicates that the bonding position in the ring is arbitrary; in formulas (DI-32) and (DI-33), the bond is -NH ₂ on the benzene ring means that its bonding position in the ring is arbitrary;

In formula (DI-34) and formula (DI-35), G ^{31 is} independently -O- or an alkylene group having 1 to 6 carbon atoms, G ³² is a single bond or an alkylene group having 1 to 3 carbon atoms, R ³¹ is hydrogen or an alkyl group having 1 to 20 carbon atoms. At least one -CH ₂ -of the alkyl group may be substituted by -O-, -CH = CH-, or -C≡C-, and R ³² is 6 carbon atoms. ~ 22 alkyl group, R ³³ is hydrogen or alkyl group having 1 to 22 carbon atoms, ring B ²⁵ is 1,4-phenylene or 1,4-cyclohexyl, r is 0 or 1, and -NH ₂ on the benzene ring indicates that the bonding position in the ring is arbitrary.

[4] The liquid crystal alignment agent according to item [1] or [2], wherein the tetracarboxylic dianhydride used in the synthesis of the polymer contains one selected from the following formulae (2) to (13) At least one of the group of compounds; the diamine contains at least one selected from the group of compounds represented by the following formulae (D-1) to (D-5);

At least one of the hydrogens in the formula may be substituted with -CH ₃ , -CH ₂ CH ₃ or phenyl;

In formula (D-2) and formula (D-4), X and Y are independently a single bond, -O-, -NH-, -S-, or an alkylene group having 1 to 6 carbon atoms; Formula (D In -4), a is an integer of 1 to 8; in formula (D-5), Ra is an alkyl group having 1 to 3 carbons; and at least one hydrogen of a benzene ring in the formula may be passed through -CH ₃ Was replaced.

[5] The liquid crystal alignment agent according to any one of the items [1] to [4], wherein the polyamino acid and its derivative are such that at least one of a tetracarboxylic dianhydride and a diamine has a photoreaction. Polymer (a) obtained by reacting a raw material monomer of a natural structure.

[6] The liquid crystal alignment agent according to the item [5], wherein the diamine includes 4,4'-diaminoazobenzene.

[7] The liquid crystal alignment agent according to item [5] or [6], which includes not only the polymer (a) but also a tetracarboxylic dianhydride selected from a group having no photoreactive structure and a group having no At least one polymer (b) of polyamidic acid and a derivative thereof obtained by reacting a diamine having a photoreactive structure.

[8] The liquid crystal alignment agent according to any one of the items [1] to [7], wherein the tetracarboxylic dianhydride used in the synthesis of the polymer (b) contains a compound selected from the following formula (2) to At least one of a group of compounds represented by formula (13); the diamine contains at least one selected from the group of compounds represented by the following formula (D-1) to formula (D-5);

At least one of the hydrogens in the formula may be substituted with -CH ₃ , -CH ₂ CH ₃ or phenyl;

In formula (D-2) and formula (D-4), X and Y are independently a single bond, -O-, -NH-, -S-, or an alkylene group having 1 to 6 carbon atoms; formula (D In -4), a is an integer of 1 to 8; in formula (D-5), Ra is an alkyl group having 1 to 3 carbons; and at least one hydrogen of a benzene ring in the formula may be passed through -CH ₃ Was replaced.

[9] The liquid crystal alignment agent according to any one of the items [1] to [8], further comprising a compound selected from the group consisting of an oxazine compound, an oxazoline compound, an epoxy compound, and a compound containing a silane coupling agent. At least one of the group.

[10] A liquid crystal alignment film formed using the liquid crystal alignment agent according to any one of [1] to [9].

[11] A liquid crystal display element including the liquid crystal alignment film according to the item [10].

The liquid crystal alignment agent of the present invention in which a polymer obtained from a tetracarboxylic dianhydride and a diamine is dissolved in the solvent obtained by mixing the first solvent to the fourth solvent can be used to print a liquid crystal alignment film by an inkjet method. In the production process of the used coating film, uneven streaks of the coating film are prevented, shrinkage of the film or occurrence of unevenness of edges is suppressed, and good printability is exhibited. In addition, the liquid crystal alignment agent prepared by blending two or more kinds of polymers also exhibited the same effect.

1‧‧‧ Nozzle

2‧‧‧ Ink Drops

3‧‧‧ mirror reflection image

4‧‧‧ No ejection caused by nozzle clogging

5‧‧‧ Inclined spray caused by nozzle clogging

6‧‧‧ coated film

7‧‧‧ substrate

8‧‧‧ Uneven edges

FIG. 1 is an image obtained by photographing a state of ejection in an inkjet ejection experiment (Example 1) using a polyamine solution PC-1.

FIG. 2 is an image obtained by photographing a state of ejection in an inkjet ejection experiment (Comparative Example 1) using a polyamic acid solution PC-27.

FIG. 3 is a microscope photograph for measuring edge irregularity in the linearity evaluation of the edge (Example 1) using the polyamic acid solution PC-1.

FIG. 4 is a microscope photograph for measuring edge irregularity in the linearity evaluation of the edge (Comparative Example 1) using the polyamic acid solution PC-27.

FIG. 5 is a photograph obtained by taking photos of the unevenness of the in-plane streak in the evaluation of the unevenness of the in-plane streak using the polyamic acid solution PC-1 (Example 1).

FIG. 6 is a photograph obtained by photographing the unevenness of the in-plane stripes in the evaluation of the unevenness of the in-plane stripes (Comparative Example 1) using the polyamic acid solution PC-27.

The subject of the present invention is a liquid crystal alignment agent containing at least one polymer and a solvent selected from the group consisting of polyamic acid and its derivatives. The solvent used in the liquid crystal alignment agent of the present invention is divided into the following four groups.

The first solvent is selected from the group consisting of a polar organic solvent having good solubility to a polymer forming the alignment film.

Specific examples of such polar organic solvents are: N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethylimidazolidone, N-methylcaprolactam, N- Methamphetamine, N, N-dimethylacetamide, dimethylmethane, N, N-dimethylformamide, N, N-diethylformamide, diethylacetamidine Lactones such as amines and γ-butyrolactone.

Among these compounds, preferred solvents in terms of boiling points are: N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethylimidazolidone, and γ-butyrolactone. .

In order to avoid cracking of the film caused by evaporation of the low-boiling solvent before the fluorenimidization, and to avoid the residual of the high-boiling solvent, the non-uniformity caused by the liquid oozing into the liquid crystal after the panel is assembled, the boiling point of the first solvent is relatively low. It is preferably in a range of 190 ° C to 250 ° C.

The second solvent is characterized in that the surface energy is less than 30 mN / m, is relatively small, and the coating property to the substrate is good. Specific examples include alcohols and ethers.

Specific examples of alcohols are: butyl cellosolve (ethylene glycol monobutyl ether), ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, and propylene glycol monopropyl ether , 1-butoxy-2-propanol, ethyl lactate, methyl lactate, propyl lactate.

Specific examples of the ethers are ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, and diethylene glycol propyl Methyl ether, propylene glycol monoethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether ethyl Acid ester, propylene glycol monomethyl ether propionate.

Among these compounds, preferred solvents in terms of boiling points are: butyl cellosolve (ethylene glycol monobutyl ether), 1-butoxy-2-propanol, ethylene glycol diethyl ether, and diethylene glycol dimethyl ether. Ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, and diethylene glycol propyl methyl ether. More preferred solvents are: butyl cellosolve, 1-butoxy-2-propanol, diethylene glycol ethyl methyl ether, and diethylene glycol propyl methyl ether.

In order to prevent the liquid from drying too quickly due to the evaporation of the low boiling point solvent, the uniformity of the coating film is deteriorated, and to avoid the residual of the high boiling point solvent, it will bleed into the liquid crystal after the panel assembly and cause unevenness. The boiling point of the two solvents is preferably in the range of 120 ° C to 200 ° C.

The third solvent is a solvent that improves the diffusivity of the solution. By mixing these solvents, unevenness in streaks of the coating film can be prevented.

Specific examples of such a solvent include methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, and methyl isoamyl. Ketones such as methyl ketone, methyl-3-methoxypropionate, and dipentyl ether. Among these compounds, preferred solvents are methyl isobutyl ketone, diisobutyl ketone, and dipentyl ether. More preferred solvents are diisobutyl ketone and dipentyl ether.

The fourth solvent has the effects of suppressing film shrinkage and preventing unevenness of the edges of the coating film. This effect is considered to be caused by the fact that the fourth solvent has a boiling point in a temperature region close to the first solvent, and is higher than the boiling points of the second solvent and the third solvent. That is, the reason is considered to be that the fourth solvent with a high boiling point slows down the drying speed when the ejection liquid is diffused, and in particular, the evaporation of the solvent in the edge portion is suppressed.

Specific examples of the preferred fourth solvent are diethylene glycol ethylpropyl ether, diethylene glycol butyl methyl ether, and diethylene glycol butyl ether.

Since these four solvents each have different characteristics, it is important to have a composition ratio described below.

The ratio of the first solvent to the weight of the entire solvent is 20% to 89% by weight, preferably 30% to 84% by weight, and more preferably 45% to 75% by weight.

In order to prevent the precipitation of the polymer in the solution, the clogging of the nozzles or heads of the inkjet device, and the in-plane unevenness of the coating film, the first solvent is used in a proportion of 20% by weight or more based on the total solvent weight. On the other hand, since the amount of the second solvent as the lean solvent is reduced and the printability is not deteriorated, it is used at a ratio of 89% by weight or less with respect to the total solvent weight.

The ratio of the second solvent to the weight of the entire solvent is 10% to 60% by weight, preferably 15% to 50% by weight, and more preferably 20% to 45% by weight.

The second solvent is used in a proportion of 10% by weight or more based on the total solvent weight in order to prevent the occurrence of poor printing or liquid shrinkage caused by evaporation from the edge portion. In contrast, the proportion of good solvents is reduced. In order to prevent the precipitation of polymers in the solution, blockage of the nozzles or heads of the inkjet device, and in-plane unevenness of the coating film, the weight of the solvent is 60% by weight Use at a ratio of less than%.

The ratio of the third solvent to the weight of the entire solvent is from 0.1% to 15% by weight, preferably from 0.1% to 10% by weight, and more preferably from 0.1% to 5% by weight.

In order to prevent deterioration of the liquid diffusivity and unevenness of streaks in the traveling direction of the head, the third solvent is used at a ratio of 0.1% by weight or more based on the weight of the entire solvent. In contrast, the liquid is excessively diffused, and in order to prevent the linearity of the edges from being deteriorated, it is used at a ratio of 15% by weight or less with respect to the total solvent weight.

The ratio of the fourth solvent to the weight of the entire solvent is 0.1% to 20% by weight, preferably 0.1% to 15% by weight, and more preferably 0.1% to 10% by weight.

In order to exert the effect of maintaining the linearity of the edge and the effect of good liquid diffusion, the fourth solvent is used at a ratio of 0.1% by weight or more based on the total solvent weight. On the contrary, in order to prevent the drying of the coating film or the occurrence of in-plane unevenness, Since the uniformity is deteriorated, it is used at a ratio of 20% by weight or less based on the total solvent weight.

The polyamidic acid and its derivatives of the present invention will be described.

The polyamidic acid and its derivatives of the present invention are reaction products of tetracarboxylic dianhydride and diamine. The polyamic acid derivative is a component that is dissolved in a solvent when a liquid crystal alignment agent described later containing a solvent is made. When the liquid crystal alignment agent is made into a liquid crystal alignment film, a polyfluorene can be formed. Imine is a component of a liquid crystal alignment film as a main component. Examples of the polyamidic acid derivative include soluble polyamidoimide, polyamidate, polyamidoamine, and the like, and more specifically, 1) all of polyamidate Polyimide formed by dehydration and ring closure reaction of amine group and carboxyl group; 2) Partial polyimide produced by dehydration and ring closure reaction partially; 4) a polyamic acid-polyamine copolymer obtained by substituting a part of the acid dianhydride contained in the tetracarboxylic dianhydride compound with an organic dicarboxylic acid and reacting; further 5) making the polyamine A part or all of the acid-polyamidine copolymer is a polyamidene and imine obtained by performing a dehydration ring-closure reaction. The polyamidic acid and its derivative may be one kind of compound or two or more kinds. In addition, the polyphosphonic acid and its derivative may be a compound having a structure of a reaction product of a tetracarboxylic dianhydride and a diamine, and may include the use of other raw materials by using a tetracarboxylic dianhydride and a diamine. A reaction product obtained by a reaction other than the reaction of.

The tetracarboxylic dianhydride used in order to manufacture the polyamic acid and its derivative contained in the liquid crystal aligning agent of this invention is demonstrated. The tetracarboxylic dianhydride used in the present invention can be selected from known tetracarboxylic dianhydrides without limitation. The tetracarboxylic dianhydride may It is any of the aromatic systems (including heteroaromatic ring systems) in which the dicarboxylic anhydride is directly bonded to the aromatic ring, and the aliphatic systems (including heterocyclic systems) in which the dicarboxylic anhydride is not directly bonded to the aromatic ring. A group of people. Tetracarboxylic dianhydride allows one compound to react with a diamine, or two or more compounds can be mixed to react with a diamine. The term "tetracarboxylic dianhydride" as used in this specification refers not only to a single compound but also to a mixture of two or more compounds.

In terms of ease of obtaining raw materials, ease of polymer polymerization, and electrical characteristics of the film, the preferred examples of the tetracarboxylic dianhydride described above include Formula (AN-I) to Formula (AN -Tetracarboxylic dianhydride represented by -VII).

In formula (AN-I), formula (AN-IV), and formula (AN-V), X is independently a single bond or -CH _2- . In the formula (AN-II), G is a single bond, an alkylene group having 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) ₂ -or- C (CF ₃ ) _2- . In the formulae (AN-II) to (AN-IV), Y is independently one selected from the group of a trivalent group described below, and is bonded to an arbitrary carbon with a bond, and at least the group is at least One hydrogen can be substituted with methyl, ethyl or phenyl.

In formulas (AN-III) to (AN-V), ring A ¹⁰ is a group of a monocyclic hydrocarbon having 3 to 10 carbons or a group of a condensing polycyclic hydrocarbon having 6 to 30 carbons. At least one hydrogen of the group may be substituted by a methyl group, an ethyl group, or a phenyl group, and a bonding bond hanging on the ring is connected to any carbon constituting the ring, and two bonding bonds may be connected to the same carbon. In the formula (AN-VI), X ¹⁰ is an alkylene group having 2 to 6 carbon atoms, Me represents a methyl group, and Ph represents a phenyl group. In formula (AN-VII), G ^{10 is} independently -O-, -COO-, or -OCO-, and r is independently 0 or 1.

More specifically, the tetracarboxylic dianhydride represented by the following formula (AN-1)-(AN-16-14) is mentioned.

[Tetracarboxylic dianhydride represented by formula (AN-1)]

In Formula (AN-1), G ¹¹ is a single bond, an alkylene group having 1 to 12 carbon atoms, 1,4-phenylene group, or 1,4-cyclohexyl group. X ^{11 is} independently a single bond or -CH _2- . G ^{12 is} independently any one of the following trivalent groups.

When G ¹² is> CH-, hydrogen of> CH- may be replaced by -CH ₃ . When G ¹² is> N-, G ^{11 is} not a single bond and -CH _2- , and X ^{11 is} not a single bond. R ¹¹ is hydrogen or -CH ₃ .

Examples of the tetracarboxylic dianhydride represented by the formula (AN-1) include compounds represented by the following formula.

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

[Tetracarboxylic dianhydride represented by formula (AN-2)]

In the formula (AN-2), R ^{12 is} independently hydrogen, -CH ₃ , -CH ₂ CH ₃ , or phenyl.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-2) include compounds represented by the following formula.

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

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

Examples of the tetracarboxylic dianhydride represented by the formula (AN-3) include compounds represented by the following formula.

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

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

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

Examples of the tetracarboxylic dianhydride represented by the formula (AN-4) include compounds represented by the following formula.

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

[Tetracarboxylic dianhydride represented by formula (AN-5)]

In Formula (AN-5), R ¹¹ is hydrogen or -CH ₃ . R ¹¹ where the bonding position is not fixed to the carbon atom constituting the benzene ring means that the bonding position in the benzene ring is arbitrary.

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

[Tetracarboxylic dianhydride represented by formula (AN-6)]

In Formula (AN-6), X ^{11 is} independently a single bond or -CH _2- . X ¹² is -CH _2- , -CH ₂ CH _2- , or -CH = CH-. n is 1 or 2.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-6) include compounds represented by the following formula.

[Tetracarboxylic dianhydride represented by formula (AN-7)]

In Formula (AN-7), X ¹¹ is a single bond or -CH _2- .

Examples of the tetracarboxylic dianhydride represented by the formula (AN-7) include compounds represented by the following formula.

[Tetracarboxylic dianhydride represented by formula (AN-8)]

In Formula (AN-8), X ¹¹ is a single bond or -CH _2- . R ¹² is hydrogen, -CH ₃ , -CH ₂ CH ₃ , or phenyl, and ring A ¹² is a cyclohexane ring or a cyclohexene ring.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-8) include compounds represented by the following formula.

[Tetracarboxylic dianhydride represented by formula (AN-9)]

In Formula (AN-9), r is independently 0 or 1.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-9) include compounds represented by the following formula.

[Tetracarboxylic dianhydride represented by formula (AN-10-1) and formula (AN-10-2)]

[Tetracarboxylic dianhydride represented by formula (AN-11)]

In the formula (AN-11), the ring A ^{11 is} independently a cyclohexane ring or a benzene ring.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-11) include compounds represented by the following formula.

[Tetracarboxylic dianhydride represented by formula (AN-12)]

In the formula (AN-12), the ring A ^{11 is} each independently a cyclohexane ring or a benzene ring.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-12) include compounds represented by the following formula.

[Tetracarboxylic dianhydride represented by formula (AN-13)]

In the formula (AN-13), X ¹³ is an alkylene group having 2 to 6 carbon atoms, and Ph represents a phenyl group.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-13) include compounds represented by the following formula.

In the formula (AN-13-1), Ph represents a phenyl group.

[Tetracarboxylic dianhydride represented by formula (AN-14)]

In the formula (AN-14), G ^{14 is} independently -O-, -COO-, or -OCO-, and r is independently 0 or 1.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-14) include compounds represented by the following formula.

[Tetracarboxylic dianhydride represented by formula (AN-15)]

In Formula (AN-15), w is an integer of 1-10.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-15) include compounds represented by the following formula.

Examples of the tetracarboxylic dianhydride other than the above include the following compounds.

Among the acid dianhydrides, preferable materials for improving each characteristic will be described. In the case where it is important to improve the alignment of the liquid crystal, compounds represented by the formula (AN-1), (AN-3), and (AN-4) are preferred, and formula (AN-1-2) is particularly preferred Compounds represented by Formula (AN-1-13), Formula (AN-3-2), Formula (AN-4-17) and Formula (AN-4-29), wherein ), M = 4 or 8 is preferred, and in formula (AN-4-17), m = 4 or 8 is preferred, and m = 8 is particularly preferred.

In the case where it is important to improve the transmittance of a liquid crystal display element, the acid Among the anhydrides, formula (AN-1-1), formula (AN-1-2), formula (AN-2-1), formula (AN-3-1), and formula (AN-4-17) are preferred. , Formula (AN-4-30), formula (AN-5-1), formula (AN-7-2), formula (AN-10), formula (AN-16-3) and formula (AN-16- The compound represented by 4), wherein m = 4 or 8 is preferred in formula (AN-1-2), and m = 4 or 8 is preferred in formula (AN-4-17). It is m = 8.

In the case of increasing the voltage holding ratio (VHR) of the liquid crystal display element, among the acid dianhydrides, the formula (AN-1-1), the formula (AN-1-2), and the formula are preferred. (AN-2-1), formula (AN-3-1), formula (AN-4-17), formula (AN-4-30), formula (AN-7-2), formula (AN-10) Compounds represented by Formula (AN-16-3) and Formula (AN-16-4), wherein in Formula (AN-1-2), it is preferably m = 4 or 8, and in Formula (AN-4 In -17), m = 4 or 8 is preferable, and m = 8 is particularly preferable.

Increasing the reduction of the volume resistance value of the liquid crystal alignment film to increase the residual charge (the reduction speed of the residual direct-current (DC) in the alignment film) can be effectively used as one of the methods to prevent scoring. In the case where this purpose is valued In the following, among the acid dianhydrides, formula (AN-1-13), formula (AN-3-2), formula (AN-4-21), formula (AN-4-29), and formula ( AN-11-3).

As the raw material of the polymer contained in the liquid crystal alignment agent of the present invention, the tetracarboxylic dianhydride that is more suitably used is at least one selected from the group of the compounds represented by the following formulae (2) to (13). By.

At least one of the hydrogens in the formula may be substituted with -CH ₃ , -CH ₂ CH ₃ or phenyl.

In addition, the unsubstituted compound in the formula (2) corresponds to the compound of the formula (AN-3-2), and the unsubstituted compound in the formula (3) corresponds to the formula (AN-2-1) ), The unsubstituted compound in formula (4) corresponds to the compound of formula (AN-1-1), and the unsubstituted compound in formula (5) corresponds to the formula (AN-3) -1) a compound, an unsubstituted compound in the formula (6) corresponds to the compound of the formula (AN-1-13), and an unsubstituted compound in the formula (7) corresponds to the formula (AN) -16-1), the unsubstituted compound in formula (8) corresponds to the compound of formula (AN-7-2), and the unsubstituted compound in formula (9) The compound corresponds to the compound of the formula (AN-10-1), the unsubstituted compound in the formula (10) corresponds to the compound of m = 8 in the formula (AN-4-17), and the formula (11) The unsubstituted compound in is equivalent to the compound of formula (AN-4-21), the unsubstituted compound in formula (12) is equivalent to the compound of formula (AN-5-1), and, The unsubstituted compound in the formula (13) corresponds to the compound of the formula (AN-4-5).

The diamine and the dihydrazine used for producing the polyamidic acid and its derivative contained in the liquid crystal aligning agent of this invention are demonstrated. The diamine and dihydrazine used in the present invention can be selected from known diamines and dihydrazine without limitation. Diamine can react one compound with tetracarboxylic dianhydride, or it can also mix two or more compounds to react with tetracarboxylic dianhydride. The "diamine" in this specification means not only one kind of compound but also a mixture of two or more kinds of compounds in its meaning. In addition, in this specification, dihydrazine is also assumed to be operated as a "diamine".

Diamines can be divided into two types based on their structure. That is, when a skeleton to which two amine groups are connected is regarded as a main chain, the diamine is a diamine having a side chain group that is a group branched on an autonomous chain and a diamine having no side chain group. The side chain group is a group having an effect of increasing the pretilt angle. The side chain group having the above effect must be a group having 3 or more carbon atoms. Specific examples include an alkyl group having 3 or more carbon atoms, an alkoxy group having 3 or more carbon atoms, and an alkoxyalkyl group having 3 or more carbon atoms. And a group having a steroid skeleton. A group having one or more rings, and a terminal ring having any of an alkyl group having 1 or more carbon atoms, an alkoxy group having 1 or more carbon atoms, and an alkoxyalkyl group having 2 or more carbon atoms as substituents The group also has an effect as a side chain group. In the following description, sometimes there will be The diamine of the side chain group is called a side chain type diamine. In addition, a diamine having no side chain group as described above is sometimes referred to as a non-side chain type diamine.

By appropriately using the non-side chain type diamine and the side chain type diamine separately, it is possible to correspond to the respective pretilt angles required. The side chain type diamine is preferably used in combination to such an extent that the characteristics of the present invention are not impaired. In addition, as for the side chain type diamine and the non-side chain type diamine, it is preferable to select and use it for the purpose of improving the vertical alignment property to the liquid crystal, the voltage holding ratio, the mark retention property, and the alignment property.

The non-side chain type diamine will be described. Examples of known diamines having no side chain include diamines of the following formulae (DI-1) to (DI-16).

In the formula (DI-1), G ²⁰ is -CH _2- , at least one -CH ₂ -may be substituted with -NH-, -O-, m is an integer from 1 to 12, and at least one of alkylene Hydrogen may be replaced by -OH.

In formulas (DI-3) and (DI-5) to (DI-7), G ^{21 is} independently a single bond, -NH-, -NCH _3- , -O-, -S-, -SS- , -SO _2- , -CO-, -COO-, -CONCH _3- , -CONH-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -,-(CH ₂ ) _m -,- O- (CH ₂ ) _m -O-, -N (-Ra)-(CH ₂ ) _k -N (-Ra)-,-(OC ₂ H ₄ ) _m -O-, -O-CH ₂ -C (CF ₃ ) ₂ -CH ₂ -O-, -O-CO- (CH ₂ ) _m -CO-O-, -CO-O- (CH ₂ ) _m -O-CO-,-(CH ₂ ) _m -NH- (CH ₂ ) _m- , -CO- (CH ₂ ) _k -NH- (CH ₂ ) _k -,-(NH- (CH ₂ ) _m ) _k -NH-, -CO-C ₃ H ₆ -(NH-C ₃ H ₆ ) _n -CO- or -S- (CH ₂ ) _m -S-, Ra is an alkyl group having 1 to 3 carbon atoms, m is independently an integer of 1 to 12, and k is 1 An integer of ~ 5, where n is 1 or 2.

In the formula (DI-4), s is independently an integer of 0 to 2. In formula (DI-6) and formula (DI-7), G ^{22 is} independently a single bond, -O-, -S-, -CO-, -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -NH-, or an alkylene group having 1 to 10 carbon atoms. At least one hydrogen of the cyclohexane ring and the benzene ring in the formulae (DI-2) to (DI-7) may pass through -F, -Cl, an alkyl group having 1 to 3 carbon atoms, -OCH ₃ , -OH, In addition to -CF ₃ , -CO ₂ H, -CONH ₂ , -NHC ₆ H ₅ , phenyl or benzyl, in addition, in formula (DI-4), at least one hydrogen of the benzene ring may be selected from One of the groups represented by the formulae (DI-4-a) to (DI-4-e) is substituted. A group whose bonding position is not fixed to a carbon atom constituting a ring indicates that its bonding position in the ring is arbitrary. The bonding position of -NH ₂ on the cyclohexane ring or benzene ring is any position other than the bonding position of G ²¹ or G ²² .

In the formula (D1-4-a) and the formula (DI-4-b), R ^{20 is} independently hydrogen or -CH ₃ .

In Formula (DI-11), r is 0 or 1. In formulas (DI-8) to (DI-11), the bonding position of -NH ₂ bonded to the ring is arbitrary.

In the formula (DI-12), R ²¹ and R ^{22 are} independently an alkyl group or a phenyl group having 1 to 3 carbon atoms, and G ^{23 is} independently an alkylene group, a phenylene group, or an alkyl group having 1 to 6 carbon atoms. For substituted phenylene, w is an integer from 1 to 10. In formula (DI-13), R ^{23 is} independently an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms or -Cl, p is independently an integer of 0 to 3, and q is 0 to 4 Integer. In formula (DI-14), ring B is a monocyclic heterocyclic aromatic group, and R ²⁴ is hydrogen, -F, -Cl, alkyl having 1 to 6 carbons, alkoxy, vinyl, and alkynyl , Q is independently an integer from 0 to 4. In formula (DI-15), ring C is a heterocyclic aromatic group or a heterocyclic aliphatic group. In the formula (DI-16), G ²⁴ is a single bond, an alkylene group or a 1,4-phenylene group having 2 to 6 carbon atoms, and r is 0 or 1. In addition, a group in which the bonding position is not fixed to the carbon atom constituting the ring indicates that the bonding position in the ring is arbitrary. In formulas (DI-13) to (DI-16), the bonding position of -NH ₂ bonded to the ring is arbitrary.

Specific examples of the following formula (DI-1-1) to formula (DI-16-1) include diamines having no side chains in the formulas (DI-1) to (DI-16).

Examples of the diamine represented by the formula (DI-1) are shown below.

In Formula (DI-1-7) and Formula (DI-1-8), k is an integer of 1-3 each independently.

Examples of the diamine represented by the formula (DI-2) and the formula (DI-3) are shown below.

Examples of the diamine represented by the formula (DI-4) are shown below.

Examples of the diamine represented by the formula (DI-5) are shown below.

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

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

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

In the formula (DI-5-30), k is an integer of 1 to 5.

In formulas (DI-5-35) to (DI-5-37) and (DI-5-39), m is an integer of 1 to 12, and formulas (DI-5-38) and (DI-5 In -39), k is an integer of 1 to 5, and in formula (DI-5-40), n is an integer of 1 or 2.

Examples of the diamine represented by the formula (DI-6) are shown below.

Examples of the diamine represented by the formula (DI-7) are shown below.

In Formula (DI-7-3) and Formula (DI-7-4), m is an integer of 1 to 12, and n is independently 1 or 2.

Examples of the diamine represented by the formula (DI-8) are shown below.

Examples of the diamine represented by the formula (DI-9) are shown below.

Examples of the diamine represented by the formula (DI-10) are shown below.

Examples of the diamine represented by the formula (DI-11) are shown below.

Examples of the diamine represented by the formula (DI-12) are shown below.

Examples of the diamine represented by the formula (DI-13) are shown below.

Examples of the diamine represented by the formula (DI-14) are shown below.

Examples of the diamine represented by the formula (DI-15) are shown below.

Examples of the diamine represented by the formula (DI-16) are shown below.

Dihydrazide will be described. Examples of known dihydrazine having no side chain include the following formulae (DIH-1) to (DIH-3).

In formula (DIH-1), G ²⁵ is a single bond, an alkylene group having 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- .

In the formula (DIH-2), the ring D is a cyclohexane ring, a benzene ring, or a naphthalene ring, and at least one hydrogen of the group may be substituted by a methyl group, an ethyl group, or a phenyl group. In the formula (DIH-3), the ring E is independently a cyclohexane ring or a benzene ring, at least one hydrogen of the group may be substituted by a methyl group, an ethyl group, or a phenyl group, and Y is a single bond and the carbon number is 1 ~ 20 alkylene, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- . In formula (DIH-2) and formula (DIH-3), the bonding position of -CONHNH ₂ bonded to the ring is arbitrary.

Examples of the formulae (DIH-1) to (DIH-3) are shown below.

In Formula (DIH-1-2), m is an integer of 1-12.

The above-mentioned non-side chain diamine and hydrazine have effects of improving the electrical characteristics such as lowering the ion density of the liquid crystal display element. When a non-side chain type diamine and / or hydrazine are used as the diamine used to produce the polyamidic acid or a derivative thereof used in the liquid crystal alignment agent of the present invention, the diamine is preferably The proportion of the total amount of dihydrazine is 0 to 90 mol%, and more preferably 0 to 50 mol%.

The side chain type diamine will be described. Examples of the side chain group of the side chain diamine include Under groups.

Examples of the side chain group include alkyl, alkyloxy, alkyloxyalkyl, alkylcarbonyl, alkylcarbonyloxy, alkyloxycarbonyl, alkylaminocarbonyl, alkenyl, and alkenyl Alkoxy, alkenylcarbonyl, alkenylcarbonyloxy, alkenyloxycarbonyl, alkenylaminocarbonyl, alkynyl, alkynyloxy, alkynylcarbonyl, alkynyloxy, alkynyloxycarbonyl, Alkynylaminocarbonyl and the like. The alkyl group, alkenyl group, and alkynyl group in these groups are all groups having 3 or more carbon atoms. Among them, in the alkyloxyalkyl group, the entire group may be 3 or more carbon atoms. These groups may be linear or branched.

Further, provided that the terminal ring has an alkyl group having 1 or more carbon atoms, an alkoxy group having 1 or more carbon atoms, or an alkoxyalkyl group having 2 or more carbon atoms as a substituent, a phenyl group and a phenylalkyl group can be exemplified. , Phenylalkyloxy, phenyloxy, phenylcarbonyl, phenylcarbonyloxy, phenyloxycarbonyl, phenylaminocarbonyl, phenylcyclohexyloxy, cycloalkyl having 3 or more carbon atoms , Cyclohexylalkyl, cyclohexyloxy, cyclohexyloxycarbonyl, cyclohexylphenyl, cyclohexylphenylalkyl, cyclohexylphenyloxy, bis (cyclohexyl) oxy, bis (cyclohexyl) alkane , Bis (cyclohexyl) phenyl, bis (cyclohexyl) phenylalkyl, bis (cyclohexyl) oxycarbonyl, bis (cyclohexyl) phenyloxycarbonyl, and cyclohexylbis (phenyl) oxy A carbonyl group and other ring structures.

Furthermore, a group having two or more benzene rings, a group having two or more cyclohexane rings, or a two or more ring group including a benzene ring and a cyclohexane ring can be listed, and the bonding group is independently It is a single bond, -O-, -COO-, -OCO-, -CONH-, or an alkylene group having 1 to 3 carbon atoms. The terminal ring has an alkyl group having 1 or more carbon atoms and a fluorine-substituted alkyl group having 1 or more carbon atoms. Group, alkoxy group having 1 or more carbon atoms, or alkoxyalkyl group having 2 or more carbon atoms as Is a ring group of a substituent. A group having a steroid skeleton is also effective as a side chain group.

Examples of the diamine having a side chain include compounds represented by the following formulae (DI-31) to (DI-35).

In formula (DI-31), G ²⁶ is a single bond, -O-, -COO-, -OCO-, -CO-, -CONH-, -CH ₂ O-, -OCH _2- , -CF ₂ O- , -OCF ₂ -or-(CH ₂ ) _{m '} -, m' is an integer from 1 to 12. Preferred examples of G ²⁶ are single bonds, -O-, -COO-, -OCO-, -CH ₂ O-, and alkylene groups having 1 to 3 carbon atoms. Particularly preferred examples are single bonds, -O-, -COO-, -OCO-, -CH ₂ O-, -CH _2- , and -CH ₂ CH _2- . R ²⁵ is an alkyl group having 3 to 30 carbon atoms, a phenyl group, a group having a steroid skeleton, or a group represented by the following formula (DI-31-a). In the alkyl group, at least one hydrogen may be substituted with -F, and at least one -CH ₂ -may be substituted with -O-, -CH = CH-, or -C≡C-. The hydrogen of the phenyl group can be obtained through -F, -CH ₃ , -OCH ₃ , -OCH ₂ F, -OCHF ₂ , -OCF ₃ , alkyl group having 3 to 30 carbon atoms, or alkoxy group having 3 to 30 carbon atoms To replace. The bonding position of -NH _{2 which} is bonded to a benzene ring is shown at any position in the ring, but the bonding position is preferably meta or para. That is, when the bonding position of the group "R ²⁵ -G ^26- " is set to one position, the two bonding positions are preferably 3 positions and 5 positions, or 2 positions and 5 positions.

In the formula (DI-31-a), G ²⁷ , G ²⁸ and G ²⁹ are bonding groups, and these groups are independently a single bond or an alkylene group having 1 to 12 carbon atoms. The above -CH ₂ -may be replaced by -O-, -COO-, -OCO-, -CONH-, -CH = CH-. Ring B ²¹ , Ring B ²² , Ring B ²³ and Ring B ^{24 are} independently 1,4-phenylene, 1,4-cyclohexyl, 1,3-dioxane-2,5-diyl, pyrimidine -2,5-diyl, pyridine-2,5-diyl, naphthalene-1,5-diyl, naphthalene-2,7-diyl, or anthracene-9,10-diyl, ring B ²¹ , ring B ^In ring ²² , ring B ²³ and ring B ²⁴ , at least one hydrogen may be replaced by -F or -CH ₃ , and s, t, and u are independently integers of 0 to 2, and the total of these is 1 to 5, when s When, t or u is 2, the two bonding groups in each parenthesis may be the same or different, and the two rings may be the same or different. R ²⁶ is hydrogen, -F, -OH, alkyl having 1 to 30 carbons, fluorine-substituted alkyl having 1 to 30 carbons, alkoxy having 1 to 30 carbons, -CN, -OCH ₂ F,- OCHF ₂ or -OCF ₃ , and at least one -CH ₂ -of the alkyl group having 1 to 30 carbon atoms may be substituted with a divalent group represented by the following formula (DI-31-b).

In formula (DI-31-b), R ²⁷ and R ^{28 are} independently an alkyl group having 1 to 3 carbon atoms, and v is an integer of 1 to 6. Preferred examples of R ²⁶ are an alkyl group having 1 to 30 carbon atoms and an alkoxy group having 1 to 30 carbon atoms.

In formula (DI-32) and formula (DI-33), G ^{30 is} independently a single bond, -CO- or -CH _2- , R ^{29 is} independently hydrogen or -CH ₃ , and R ³⁰ is hydrogen and carbon number An alkyl group of 1 to 20 or an alkenyl group of 2 to 20 carbons. At least one hydrogen of the benzene ring in the formula (DI-33) may be substituted with an alkyl group or a phenyl group having 1 to 20 carbon atoms. Furthermore, a group in which the bonding position is not fixed to any carbon atom constituting the ring indicates that the bonding position in the ring is arbitrary. Preferably in formula (DI-32) two groups "- phenylene -G ³⁰ -O-" which are bonded to a steroid nucleus the 3-position, bonded to the other steroid nucleus 6th place. The bonding position of the two groups "-phenylene-G ³⁰ -O-" on the benzene ring in the formula (DI-33) is preferably meta or opposite to the bonding position of the steroid core, respectively. Bit. In formulas (DI-32) and (DI-33), -NH ₂ bonded to a benzene ring indicates that the bonding position in the ring is arbitrary.

In Formula (DI-34) and Formula (DI-35), G ^{31 is} independently -O- or an alkylene group having 1 to 6 carbon atoms, and G ³² is a single bond or an alkylene group having 1 to 3 carbon atoms. R ³¹ is hydrogen or an alkyl group having 1 to 20 carbon atoms, and at least one -CH ₂ -of the alkyl group may be substituted by -O-, -CH = CH-, or -C≡C-. R ³² is an alkyl group having 6 to 22 carbon atoms, and R ³³ is hydrogen or an alkyl group having 1 to 22 carbon atoms. Ring B ²⁵ is 1,4-phenylene or 1,4-cyclohexyl, and r is 0 or 1. Furthermore, -NH ₂ bonded to a benzene ring indicates that the bonding position in the ring is arbitrary, but it is preferably meta or para with respect to the bonding position of G ³¹ independently.

Specific examples of the side chain diamine are shown below. Examples of the diamine having a side chain of the formulae (DI-31) to (DI-35) include compounds represented by the following formulae (DI-31-1) to (DI-35-3).

Examples of the compound represented by the formula (DI-31) are shown below.

In the formulae (DI-31-1) to (DI-31-11), R ³⁴ is an alkyl group having 1 to 30 carbon atoms or an alkoxy group having 1 to 30 carbon atoms, preferably 5 to 25 carbon atoms. Alkyl or alkoxy having 5 to 25 carbon atoms. R ³⁵ is an alkyl group having 1 to 30 carbon atoms or an alkoxy group having 1 to 30 carbon atoms, and is preferably an alkyl group having 3 to 25 carbon atoms or an alkoxy group having 3 to 25 carbon atoms.

In the formulae (DI-31-12) to (DI-31-17), R ³⁶ is an alkyl group having 4 to 30 carbon atoms, and preferably an alkyl group having 6 to 25 carbon atoms. R ³⁷ is an alkyl group having 6 to 30 carbon atoms, and preferably an alkyl group having 8 to 25 carbon atoms.

In the formulae (DI-31-18) to (DI-31-43), R ³⁸ is an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, preferably 3 to 20 carbon atoms. Alkyl or alkoxy having 3 to 20 carbon atoms. R ³⁹ is hydrogen, -F, an alkyl group having 1 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, -CN, -OCH ₂ F, -OCHF ₂ or -OCF ₃ , preferably 3 to 3 carbon atoms. An alkyl group of 25 or an alkoxy group of 3 to 25 carbon atoms. G ³³ is an alkylene group having 1 to 20 carbon atoms.

Examples of the compound represented by the formula (DI-32) are shown below.

Examples of the compound represented by the formula (DI-33) are shown below.

Examples of the compound represented by the formula (DI-34) are shown below.

In formulae (DI-34-1) to (DI-34-12), R ⁴⁰ is hydrogen or an alkyl group having 1 to 20 carbon atoms, preferably hydrogen or an alkyl group having 1 to 10 carbon atoms, and R ^{41 is} It is hydrogen or an alkyl group having 1 to 12 carbon atoms.

Examples of the compound represented by the formula (DI-35) are shown below.

In the formulae (DI-35-1) to (DI-35-3), R ³⁷ is an alkyl group having 6 to 30 carbon atoms, and R ⁴¹ is hydrogen or an alkyl group having 1 to 12 carbon atoms.

The diamine in the present invention can also use formula (DI-1-1) to formula (DI-16-1), formula (DIH-1-1) to formula (DIH-3-6), and formula (DI-31 -1) to diamines other than the diamines represented by formula (DI-35-3). Examples of the diamine include compounds represented by the following formulae (DI-36-1) to (DI-36-13).

In the formulae (DI-36-1) to (DI-36-8), R ⁴² each independently represents an alkyl group having 3 to 30 carbon atoms.

In formulas (DI-36-9) to (DI-36-11), e is an integer from 2 to 10, and in formula (DI-36-12), R ^{43 is} independently hydrogen, -NHBoc, or -N (Boc) ₂ and at least one of R ⁴³ is -NHBoc or -N (Boc) _{2. In} formula (DI-36-13), R ⁴⁴ is -NHBoc or -N (Boc) ₂ , and m is 1 Integer of ~ 12. Here, Boc is a third butoxycarbonyl group.

In the case where it is important to improve the alignment of the liquid crystal, among the diamine and dihydrazine, it is preferable to use the formula (DI-1-3), the formula (DI-5-1), and the formula (DI-5-5 ), Formula (DI-5-9), formula (DI-5-12), formula (DI-5-13), formula (DI-5-29), formula (DI-6-7), formula (DI -7-3) and the diamine represented by the formula (DI-11-2), wherein in the formula (DI-5-1), it is preferably m = 2, 4 or 6, particularly preferably m = 4, In formula (DI-5-12), m = 2 ~ 6 is preferred, and m = 5 is particularly preferred. In formula (DI-5-13), m = 1 or 2 is preferred, and m = 1.

In the case of increasing the transmittance, it is preferable to use the formula (DI-1-3), the formula (DI-2-1), the formula (DI-5-1), the diamine and the dihydrazine. The diamine represented by formula (DI-5-5), formula (DI-5-24), and formula (DI-7-3) is particularly preferably a diamine represented by (DI-2-1). In the formula (DI-5-1), m = 2, 4 or 6 is preferred, and m = 4 is particularly preferred. In the formula (DI-7-3), m = 2 or 3, n is preferred = 1 or 2, especially preferred is m = 1.

In the case where it is important to increase the VHR of a liquid crystal display element, among the diamine and dihydrazine, it is preferable to use the formula (DI-2-1), the formula (DI-4-1), and the formula (DI-4- 2), Formula (DI-4-10), Formula (DI-4-15), Formula (DI-5-28), Formula (DI-5-30) and Formula (DI-13-1) The diamine is particularly preferably a diamine represented by the formula (DI-2-1), the formula (DI-5-1), and the formula (DI-13-1). Among them, in the formula (DI-5-1), particularly preferred is m = 1, and in the formula (DI-5-30), particularly preferred is k = 2.

Reducing the volume resistance value of the liquid crystal alignment film to increase the mitigation speed of the residual charge (residual DC) in the alignment film can be effectively used as one of the methods for preventing a mark. In consideration of this purpose, it is preferable to use the formula (DI-4-1), formula (DI-4-2), formula (DI-4-10), and formula among the diamine and dihydrazine. (DI-4-15), formula (DI-5-1), formula (DI-5-12), formula (DI-5-13), formula (DI-5-28), and formula (DI-16- The diamines represented by 1) are particularly preferably diamines represented by formula (DI-4-1), formula (DI-5-1), and formula (DI-5-13). Among them, in formula (DI-5-1), m = 2, 4 or 6 is preferred, and m = 4 is particularly preferred. In formula (DI-5-12), m = 2 ~ 6 is preferred, Particularly preferred is m = 5. In formula (DI-5-13), m = 1 or 2 is preferred, and m = 1 is particularly preferred.

In each diamine, the ratio of the monoamine to the diamine is in the range of 40 mol% or less, and a part of the diamine may be substituted with the monoamine. Such substitutions may cause termination of the polymerization reaction when polyamic acid is generated, and may inhibit the progress of the polymerization reaction above. Therefore, the molecular weight of the obtained polymer (polyamino acid or a derivative thereof) can be easily controlled by the substitution, and for example, the application of the liquid crystal alignment agent can be improved without impairing the effects of the present invention. Cloth properties. As long as the diamine substituted with a monoamine does not impair the effect of the present invention, it may be one kind or two or more kinds. Examples of the monoamine include aniline, 4-hydroxyaniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, and n-decyl Amine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine Amines, n-octadecylamine, and n- eicosylamine.

The polyamidic acid or its derivative of the present invention may further contain a monoisocyanate compound in its monomer. By including a monoisocyanate compound in the monomer, The ends of the obtained polyamic acid or its derivative are modified, and the molecular weight is adjusted. By using the terminally modified polyamic acid or a derivative thereof, for example, the coating characteristics of the liquid crystal alignment agent can be improved without impairing the effects of the present invention. From the viewpoint described, the content of the monoisocyanate compound in the monomer is preferably 1 mol% to 10 mol% relative to the total amount of the diamine and tetracarboxylic dianhydride in the monomer. Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

As the raw material of the polymer contained in the liquid crystal alignment agent of the present invention, the diamine that is more suitably used is at least one selected from the group of compounds represented by the following formulae (D-1) to (D-5). One.

In formula (D-2) and formula (D-4), X and Y are independently a single bond, -O-, -NH-, -S-, or an alkylene group having 1 to 6 carbon atoms. In Formula (D-4), a is an integer of 1-8. In the formula (D-5), Ra is an alkyl group having 1 to 3 carbon atoms. In addition, at least one hydrogen of the benzene ring in the formula may be substituted by -CH ₃ .

In addition, an unsubstituted compound in the formula (D-1) corresponds to the compound of the formula (DI-4-1), and an unsubstituted compound in the formula (D-3) corresponds to the formula (DI) -13-1). In addition, it is represented by Formula (D-2) or Formula (D-5) The compound represented by the formula (DI-5) is included in the category of the formula (DI-5), and the compound represented by the formula (D-4) is included in the category of the formula (DI-7).

Specific examples of the diamine particularly preferably used among the diamines are the following formulae (D-1), (D-2-1) to (D-2-9), and (D-3) Compounds represented by Formulas (D-4-1) to (D-4-72) and Formulas (D-5-1) to (D-5-3).

In order to make the polymer contained in the liquid crystal alignment agent of the present invention have a photoreactive structure, it is preferable to use a diamine having a photoreactive structure or a tetracarboxylic dianhydride having a photoreactive structure as a raw material. A diamine having a photoreactive structure and a tetracarboxylic dianhydride having a photoreactive structure may be used in combination. Preferable examples of these monomers having a photoreactive structure are compounds represented by the following formulae (I-1) to (I-4).

Among them, a compound represented by formula (I-3) is more preferable because it exhibits greater anisotropy when forming an alignment film.

The polymer contained in the liquid crystal alignment agent of the present invention is obtained by reacting the tetracarboxylic dianhydride and diamine in a solvent. In this synthesis reaction, in addition to the selection of raw materials, no special conditions are required, and the conditions in ordinary polyamic acid synthesis can be directly applied.

The polymer contained in the liquid crystal alignment agent of the present invention may be one kind, or two or more kinds may be used in combination. The form in which two or more polymers are blended includes a case where at least one of the polymers is obtained by reacting a raw material monomer having a photoreactive structure in at least one of tetracarboxylic dianhydride and diamine. Polymer (a), at least one of the other polymers is selected from polyfluorene obtained by reacting a tetracarboxylic dianhydride having no photoreactive structure and a diamine having no photoreactive structure. Polymer (b) of at least one of amino acids and derivatives thereof. The polymer (a) has the following (photo-alignment) properties: by irradiation of energy rays such as ultraviolet rays, the photoreactive structure isomerizes, decomposes, or dimerizes, whereby the structure changes, and accordingly, the The liquid crystal molecules in contact with the polymer film are aligned in a specific direction. The polymer may be used in admixture with other polymers containing no photoreactive structure.

The liquid crystal alignment agent of the present invention may further contain components other than polyamic acid or a derivative thereof. The other components may be one type or two or more types. Examples of the other components include other polymers and compounds described later.

In the case where a plurality of polymers are blended and used in the liquid crystal alignment agent of the present invention, by controlling the structure or molecular weight of each polymer, coating it on a substrate in a manner described below and pre-drying it, for example, Photo-alignment polymer (a) The upper layer of the coating film is separated, and the other polymers (b) are separated into the lower layer of the coating film. It can be controlled by using the following phenomenon: in the mixed polymer, the polymer having a small surface energy is separated into an upper layer, and the polymer having a large surface energy is separated into a lower layer. The confirmation of the layer separation can be confirmed by the following: The surface energy of the formed alignment film is the same as or similar to the surface energy of the alignment film formed of the liquid crystal alignment agent containing only the polymer (a).

The tetracarboxylic dianhydride used for synthesizing the polymer (b) may be selected without limitation from the tetracarboxylic dianhydrides known as the tetracarboxylic dianhydrides used for Examples of the polyphosphonic acid or its derivative that is an essential component for synthesizing the liquid crystal alignment agent of the present invention include the same ones as the exemplified tetracarboxylic dianhydrides.

Among these, the acid dianhydride is preferably the formula (AN-3-2), the formula (AN-1-13), and the formula (AN-4-30) in the case where the improvement of the layer separation property is important.

In the case of increasing the transmittance of a liquid crystal display element, among the acid dianhydrides, the formula (AN-1-1), the formula (AN-1-2), the formula (AN-2-1), Formula (AN-3-1), Formula (AN-4-17), Formula (AN-4-30), Formula (AN-5-1), Formula (AN-7-2), Formula (AN-10 -1), a compound represented by the formula (AN-10-2), a formula (AN-16-3), and a formula (AN-16-4), of which the formula (AN-1-2) is preferably m = 4 or 8, in the formula (AN-4-17), m = 4 or 8 is preferred, and m = 8 is particularly preferred.

In the case where it is important to increase the VHR of a liquid crystal display element, among the acid dianhydrides, formula (AN-2-1), formula (AN-7-2), formula (AN-10-1), and formula The compound represented by (AN-10-2), formula (AN-16-3) and formula (AN-16-4), wherein in formula (AN-1-2), m = 4 or 8 is preferred .

Reducing the volume resistance value of the liquid crystal alignment film to increase the mitigation speed of the residual charge (residual DC) in the alignment film can be effectively used as one of the methods for preventing a mark. In consideration of this purpose, among the acid dianhydrides, formula (AN-1-13), formula (AN-3-2), formula (AN-4-21), and formula (AN-4) are preferred. -29) and a compound represented by the formula (AN-11-3).

The tetracarboxylic dianhydride used for synthesizing the polymer (b) preferably contains 10 mol% or more of the aromatic tetracarboxylic dianhydride with respect to the total tetracarboxylic dianhydride, and more preferably 30 mol%. the above.

Examples of the diamine and hydrazine used for synthesizing the polymer (b) are the same as those exemplified as the other diamines described below. The other diamines can be used to synthesize the essential components of the liquid crystal alignment agent of the present invention. Polyamidic acid or its derivative.

Among them, in a case where it is important to further improve the layer separation property, that is, the alignment property of the liquid crystal, among the diamine and dihydrazine, it is preferable to use the formula (DI-4-1) and the formula (DI-4-2). , Diamine represented by formula (DI-4-10), formula (DI-5-1), formula (DI-5-9), formula (DI-5-28), and formula (DIH-2-1) And hydrazine, in the formula (DI-5-1), m = 1, 2 or 4 is preferred, and m = 1 or 2 is particularly preferred.

In the case of increasing the transmittance, it is preferable to use the formula (DI-1-2), the formula (DI-2-1), the formula (DI-5-1), and the diamine and the dihydrazine. The diamine represented by formula (DI-7-3) is particularly preferably a diamine represented by formula (DI-2-1). In formula (DI-5-1), it is preferably m = 1, 2 or 4, particularly preferably m = 1 or 2, and in formula (DI-7-3), it is preferably m = 2 or 3 , N = 1 or 2, especially preferred is m = 1.

In the case where it is important to increase the VHR of a liquid crystal display element, the diamine Among dihydrazine, the formula (DI-2-1), the formula (DI-4-1), the formula (DI-4-2), the formula (DI-4-15), and the formula (DI- 5-1), formula (DI-5-28), formula (DI-5-30) and diamine represented by formula (DI-13-1), particularly preferred are formula (DI-2-1) and formula (DI-5-1) and a diamine represented by formula (DI-13-1). Among them, in formula (DI-5-1), particularly preferred is m = 1 or 2, and in formula (DI-5-30), particularly preferred is k = 2.

Reducing the volume resistance value of the liquid crystal alignment film to increase the mitigation speed of the residual charge (residual DC) in the alignment film can be effectively used as one of the methods for preventing a mark. In consideration of this purpose, among the diamine and dihydrazine, it is preferable to use formula (DI-4-1), formula (DI-4-2), formula (DI-4-10), Formula (DI-4-15), Formula (DI-5-1), Formula (DI-5-9), Formula (DI-5-12), Formula (DI-5-13), Formula (DI-5 -28), diamines represented by formula (DI-5-30) and formula (DI-16-1), particularly preferred are formula (DI-4-1), formula (DI-5-1) and formula ( DI-5-12). Among them, in formula (DI-5-1), m = 1 or 2 is preferred, in formula (DI-5-12), m = 2 ~ 6 is preferred, and m = 5 is particularly preferred. (DI-5-13) is preferably m = 1 or 2, particularly preferably m = 1, and in formula (DI-5-30), k = 2 is more preferred.

The diamine used for synthesizing the polymer (b) is preferably an aromatic diamine containing 30 mol% or more of the total diamine, and more preferably 50 mol% or more.

In the liquid crystal alignment agent of the present invention, the ratio of the polymer (a) to the total amount of the polymer (a) and the polymer (b) is preferably 10% by weight to 100% by weight, and particularly preferably 20% by weight. % ~ 100% by weight.

The polysiloxane may further contain Japanese Patent Laid-Open 2009-036966, Japanese Patent Laid-Open No. 2010-185001, Japanese Patent Laid-Open No. 2011-102963, Japanese Patent Laid-Open No. 2011-253175, Japanese Patent Laid-Open No. 2012-159825, International Publication 2008/044644, International Publication 2009/148099, International Publication 2010/074261, International Publication 2010/074264, International Publication 2010/126108, International Publication 2011/068123, International Publication 2011/068127, International Publication 2011/068128, International Publication 2012/115157, International Publication 2012/165354, etc. Siloxane.

The liquid crystal alignment agent of the present invention may further contain various additives. Examples of the various additives include oxazine compounds, oxazoline compounds, epoxy compounds, polymer compounds other than polyamic acid and its derivatives, and other low-molecular compounds, and they can be selected and used according to their respective purposes.

<Oxazine compound>

For the purpose of stabilizing the electrical characteristics of the liquid crystal display element for a long period of time, the liquid crystal alignment agent of the present invention may further contain an oxazine compound. The oxazine compound may be one kind, or two or more kinds. For the purpose, the content of the oxazine compound is preferably 0.1% to 50% by weight, more preferably 1% to 40% by weight, and even more preferably 1% by weight, relative to polyamidic acid or a derivative thereof. ~ 20% by weight. The oxazine compound will be specifically described below.

The oxazine compound is preferably an oxazine compound having a ring-opening polymerizability in addition to being soluble in a solvent that dissolves polyamic acid or a derivative thereof. The number of oxazine structures in the oxazine compound is not particularly limited.

Various structures are known in oxazine compounds. In the present invention, the structure of oxazine is not The oxazine structure in the oxazine compound is not particularly limited, and examples thereof include a oxazine structure having an aromatic group containing a condensed polycyclic aromatic group such as benzoxazine or naphthoxazine.

Examples of the oxazine compound include compounds represented by the following formulae (OX-1) to (OX-6). In addition, in the following formula, a bond represented toward the center of the ring indicates that the ring constitutes a ring and is bonded to any carbon capable of bonding with a substituent.

In formulas (OX-1) to (OX-3), L ³ and L ⁴ are organic groups having 1 to 30 carbon atoms, and in formulas (OX-1) to (OX-6), L ⁵ to L ⁸ Is hydrogen or a hydrocarbon group having 1 to 6 carbon atoms. In formula (OX-3), formula (OX-4), and formula (OX-6), Q ¹ is a single bond, -O-, -S-, -SS- , -SO _2- , -CO-, -CONH-, -NHCO-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -,-(CH ₂ ) _v- , -O- (CH ₂ ) _v -O-, -S- (CH ₂ ) _v -S-, where v is an integer from 1 to 6, in formulas (OX-5) and (OX-6), Q ^{2 is} independently a single Bond, -O-, -S-, -CO-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -or alkylene group having 1 to 3 carbon atoms, and the bond in Q ² is bonded to benzene The hydrogen on the ring or naphthalene ring may be independently substituted with -F, -CH ₃ , -OH, -COOH, -SO ₃ H, -PO ₃ H ₂ .

The oxazine compound includes an oligomer or polymer having an oxazine structure in a side chain and an oligomer or polymer having an oxazine structure in a main chain.

Examples of the oxazine compound represented by the formula (OX-1) include the following oxazine compounds.

In the formula (OX-1-2), L ^{3 is} preferably an alkyl group having 1 to 30 carbon atoms, and particularly preferably an alkyl group having 1 to 20 carbon atoms.

Examples of the oxazine compound represented by the formula (OX-2) include the following oxazine compounds.

In the formula, L ^{3 is} preferably an alkyl group having 1 to 30 carbon atoms, and particularly preferably an alkyl group having 1 to 20 carbon atoms.

Examples of the oxazine compound represented by the formula (OX-3) include an oxazine compound represented by the following formula (OX-3-I).

In formula (OX-3-I), L ³ and L ⁴ are organic groups having 1 to 30 carbons, L ⁵ to L ⁸ are hydrogen or hydrocarbon groups having 1 to 6 carbons, Q ¹ is a single bond, and -CH ₂ -, -C (CH ₃ ) _2- , -CO-, -O-, -SO _2- , -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- . Examples of the oxazine compound represented by the formula (OX-3-I) include the following oxazine compounds.

In the formula, L ³ and L ^{4 are} preferably an alkyl group having 1 to 30 carbon atoms, and particularly preferably an alkyl group having 1 to 20 carbon atoms.

Examples of the oxazine compound represented by the formula (OX-4) include the following.

Examples of the oxazine compound represented by the formula (OX-5) include the following.

Examples of the oxazine compound represented by the formula (OX-6) include the following.

Among these compounds, more preferred are: formula (OX-2-1), formula (OX-3-1), formula (OX-3-3), formula (OX-3-5), formula (OX -3-7), formula (OX-3-9), formula (OX-4-1) to formula (OX-4-6), formula (OX-5-3), formula (OX-5-4) And oxazine compounds represented by formulas (OX-6-2) to (OX-6-4).

Oxazine compounds are available with International Publication 2004/009708, Japanese Patent JP 11-12258 and JP 2004-352670 are manufactured by the same method.

The oxazine compound represented by the formula (OX-1) is obtained by reacting a phenol compound, a primary amine, and an aldehyde (see International Publication 2004/009708).

The oxazine compound represented by the formula (OX-2) is obtained by a reaction in which a primary amine is slowly added to formaldehyde, and then a compound having a naphthol-based hydroxyl group is reacted (see International Publication 2004). / 009708).

The oxazine compound represented by the formula (OX-3) is obtained by making 1 mol of a phenol compound, an aldehyde of at least 2 mol or more with respect to one phenolic hydroxyl group, and 1 mol in an organic solvent. The primary amine is obtained by performing a reaction in the presence of a secondary aliphatic amine, a tertiary aliphatic amine, or a basic nitrogen-containing heterocyclic compound (see International Publication 2004/009708 and Japanese Patent Laid-Open No. 11-12258).

The oxazine compounds represented by the formulas (OX-4) to (OX-6) are those in which 4,4'-diaminodiphenylmethane and the like have a plurality of benzene rings and an organic group that bonds them. Diamine, aldehydes such as formalin, and phenol are obtained by carrying out dehydration condensation reaction in n-butanol at a temperature of 90 ° C or higher (see Japanese Patent Laid-Open No. 2004-352670).

<Oxazoline compound>

For the purpose of stabilizing the electrical characteristics of the liquid crystal display element for a long period of time, the liquid crystal alignment agent of the present invention may further contain an oxazoline compound. An oxazoline compound is a compound having an oxazoline structure. The oxazoline compound may be a single compound or two or more compounds. For the stated purpose, oxazole is relative to polyamidic acid or its derivatives The content of the phthaloline compound is preferably 0.1% to 50% by weight, more preferably 1% to 40% by weight, and even more preferably 1% to 20% by weight. Alternatively, when the oxazoline structure in the oxazoline compound is converted into the oxazoline for the purpose, the content of the oxazoline compound is preferably 0.1% by weight relative to the polyamidic acid or a derivative thereof. ~ 40% by weight. The oxazoline compound will be specifically described below.

The oxazoline compound may have only one oxazoline structure in one compound, or may have two or more. The oxazoline compound only needs to have one oxazoline structure in one compound, and preferably has two or more. The oxazoline compound may be a polymer having a oxazoline structure in a side chain, or a copolymer. The polymer having an oxazoline structure on the side chain may be a homopolymer of a monomer having an oxazoline structure on the side chain, or a monomer having an oxazoline structure on the side chain and a non-oxazoline structure Copolymer of monomers. The copolymer having an oxazoline structure on a side chain may be a copolymer of two or more monomers having an oxazoline structure on a side chain, or may be a copolymer of two or more monomers having an oxazoline structure on a side chain. Copolymer of a monomer having an oxazoline structure.

The oxazoline structure is preferably a structure that exists in the oxazoline compound such that one or both of oxygen and nitrogen in the oxazoline structure can react with the carbonyl group of the polyamidic acid.

Examples of the oxazoline compound include 2,2'-bis (2-oxazoline), 1,2,4-tri- (2-oxazolinyl-2) -benzene, and 4-furan-2-yl Methylene-2-phenyl-4H-oxazole-5-one, 1,4-bis (4,5-dihydro-2-oxazolyl) benzene, 1,3-bis (4,5-bis Hydrogen-2-oxazolyl) benzene, 2,3-bis (4-isopropenyl-2-oxazolin-2-yl) butane, 2,2'-bis-4-benzyl-2-oxane Oxazoline, 2,6-bis (iso Propyl-2-oxazoline-2-yl) pyridine, 2,2'-isopropylidenebis (4-third-butyl-2-oxazoline), 2,2'-isopropylidenebis (4-phenyl-2-oxazoline), 2,2'-methylenebis (4-third butyl-2-oxazoline), and 2,2'-methylenebis (4- Phenyl-2-oxazoline). In addition to these compounds, polymers or oligomers having an oxazole group, such as Epocros (trade name, manufactured by Nippon Catalysts, Ltd.) can also be mentioned. Among these compounds, 1,3-bis (4,5-dihydro-2-oxazolyl) benzene is more preferable.

<Epoxy compound>

For the purpose of stabilizing the electrical characteristics of the liquid crystal display element for a long period of time, the liquid crystal alignment agent of the present invention may further contain an epoxy compound. The epoxy compound may be one kind of compound or two or more kinds of compounds. For the stated purpose, the content of the epoxy compound is preferably 0.1% to 50% by weight, more preferably 1% to 40% by weight, and even more preferably 1% by weight relative to polyamic acid or a derivative thereof. % ~ 20% by weight. The epoxy compound will be specifically described below.

Examples of the epoxy compound include various compounds having one or two or more epoxy rings in the molecule. Examples of the compound having one epoxy ring in the molecule include phenyl glycidyl ether, butyl glycidyl ether, 3,3,3-trifluoromethyl propylene oxide, styrene oxide, hexafluoro propylene oxide, Cyclohexene oxide, 3-glycidyloxypropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N-glycidylphthalimide , (Nonafluoro-N-butyl) epoxide, perfluoroethyl glycidyl ether, epichlorohydrin, epibromohydrin, N, N-diglycidylaniline, and 3- [2- (perfluorohexyl) ) Ethoxy] -1,2-propylene oxide.

Examples of the compound having two epoxy rings in the molecule include ethylene glycol. Diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol Diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromo neopentyl glycol diglycidyl ether, 3,4-epoxycyclohexenylmethyl-3 ', 4'-epoxy ring Hexene carboxylate and 3- (N, N-diglycidyl) aminopropyltrimethoxysilane.

Examples of the compound having three epoxy rings in the molecule include 2- [4- (2,3-epoxypropoxy) phenyl] -2- [4- [1,1-bis [4- ([2,3-Epoxypropoxy] phenyl)] ethyl] phenyl] propane (trade name "Techmore VG3101L" (manufactured by Mitsui Chemicals, Ltd.)).

Examples of the compound having four epoxy rings in the molecule include: 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl -M-xylylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ', N'-tetraglycidyl-4,4'- Diaminodiphenylmethane, and 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane.

In addition to the above, examples of the compound having an epoxy group in the molecule include an oligomer or a polymer having an epoxy group. Examples of the monomer having an epoxy group include glycidyl (meth) acrylate, 3,4-epoxycyclohexyl (meth) acrylate, and methyl glycidyl (meth) acrylate.

Examples of other monomers copolymerized with the monomer having an epoxy ring include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, and isopropyl (meth) acrylate. , Butyl (meth) acrylate, isobutyl (meth) acrylate, third butyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, styrene, methylstyrene, chloromethylstyrene, (3-ethyl-3-oxy) (meth) acrylate Heterocyclobutyl) methyl ester, N-cyclohexylcis-butenedifluorene imine, and N-phenylcis-butenedifluorene imine.

Preferred specific examples of the polymer of the monomer having an epoxy group include polyglycidyl methacrylate and the like. Examples of preferred specific examples of the copolymer of a monomer having an epoxy ring and other monomers include: N-phenylcis butylene diimide-glycidyl methacrylate copolymer, and N-cyclohexyl Maleimide-glycidyl methacrylate copolymer, benzyl methacrylate-glycidyl methacrylate copolymer, butyl methacrylate-glycidyl methacrylate copolymer, methyl 2-hydroxyethyl acrylate-glycidyl methacrylate copolymer, (3-ethyl-3-oxetanyl) methyl methacrylate-glycidyl methacrylate copolymer, and styrene-methyl Glycidyl acrylate copolymer.

In these examples, particularly preferred are: N, N, N ', N'-tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) ring Hexane, N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, trade name "Techmore VG3101L", 3,4-epoxy Cyclohexenylmethyl-3 ', 4'-epoxycyclohexene carboxylic acid ester, N-phenylcis butylene diimide-glycidyl methacrylate copolymer, and 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane.

More systematically, the epoxy compound includes, for example, glycidyl ether, glycidyl ester, glycidylamine, epoxy-containing acrylic resin, glycidylamidoamine, glycidyl isocyanurate, and chain Aliphatic epoxy compounds and cyclic aliphatic epoxy compounds. In addition, an epoxy compound refers to a compound having an epoxy group. Epoxy resin means a resin having an epoxy group.

Examples of the epoxy compound include glycidyl ether, glycidyl ester, glycidylamine, epoxy-containing acrylic resin, glycidylamidoamine, glycidyl isocyanurate, and chain aliphatic epoxy. Compounds, and cyclic aliphatic epoxy compounds.

Examples of the glycidyl ether include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, bisphenol type epoxy compounds, hydrogenated bisphenol-A type epoxy compounds, and hydrogenated bisphenol Phenol-F type epoxy compound, hydrogenated bisphenol-S type epoxy compound, hydrogenated bisphenol type epoxy compound, brominated bisphenol-A type epoxy compound, brominated bisphenol-F type epoxy compound, phenol novolac Varnish type epoxy compound, cresol novolac type epoxy compound, brominated phenol novolac type epoxy compound, brominated cresol novolac type epoxy compound, bisphenol A novolac type epoxy compound, naphthalene skeleton-containing Epoxy compounds, aromatic polyglycidyl ether compounds, dicyclopentadiene phenol type epoxy compounds, alicyclic diglycidyl ether compounds, aliphatic polyglycidyl ether compounds, polythioether diglycidyl ether compounds, And biphenol type epoxy compounds.

Examples of the glycidyl ester include a diglycidyl ester compound and a glycidyl epoxy compound.

Examples of the glycidylamine include polyglycidylamine compounds and glycidylamine-type epoxy resins.

Examples of the epoxy group-containing acrylic compound include homopolymers and copolymers of a monomer having an oxetanyl group.

Examples of the glycidylamidoamine include a glycidylamido-type epoxy compound.

Examples of the chain aliphatic epoxy compound include an epoxy group-containing compound obtained by oxidizing a carbon-carbon double bond of an olefin compound.

Examples of the cyclic aliphatic epoxy compound include an epoxy group-containing compound obtained by oxidizing a carbon-carbon double bond of a cycloolefin compound.

Examples of the bisphenol A-type epoxy compound include jER828, jER1001, jER1002, jER1003, jER1004, jER1007, and jER1010 (all are trade names, manufactured by Mitsubishi Chemical Corporation), and Epotohto YD-128 (Toto Kasei (Manufactured), DER-331, DER-332, DER-324 (all manufactured by The Dow Chemical Company), Epiclon 840, Epiclon 850, Epiclon 1050 (both trade names, manufactured by DIC), Epomik R-140, Epomik R-301, and Epomik (Epomik) R-304 (both trade names, manufactured by Mitsui Chemicals, Inc.).

Examples of the bisphenol F-type epoxy compound include jER806, jER807, and jER4004P (all of which are trade names, manufactured by Mitsubishi Chemical Corporation), Epotohto YDF-170, Epotohto YDF-175S, Epotohto YDF-2001 (both trade names, manufactured by Tohto Kasei Co., Ltd.), DER-354 (trade name, manufactured by The Dow Chemical Company), Epiclon 830 and Epiclon (Epiclon ) 835 (both are trade names, manufactured by DIC).

Examples of the bisphenol-type epoxy compound include 2,2-bis (4-hydroxybenzene Epoxide) -1,1,1,3,3,3-hexafluoropropane.

Examples of the hydrogenated bisphenol-A epoxy compound include: Santoto ST-3000 (trade name, manufactured by Toto Kasei Co., Ltd.), and Ricaresin HBE-100 (trade name, Shinnippon Physico Chemical ( ) And Denacol EX-252 (trade name, made by Nagase ChemteX).

Examples of the hydrogenated bisphenol-type epoxy compound include hydrogenated epoxides of 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane.

Examples of the brominated bisphenol-A epoxy compound include jER5050 and jER5051 (both are trade names, manufactured by Mitsubishi Chemical Corporation), Epotohto YDB-360, and Epotohto YDB-400 (Both trade names, manufactured by Toto Kasei Co., Ltd.), DER-530, DER-538 (both trade names, manufactured by The Dow Chemical Company), Epiclon 152, and love Epiclon 153 (both trade names, manufactured by DIC).

Examples of the phenol novolac epoxy compound include jER152 and jER154 (both are trade names, manufactured by Mitsubishi Chemical Corporation), YDPN-638 (trade name, manufactured by Tohto Kasei Corporation), and DEN431 and DEN438 (both trade names, (The Dow Chemical Company), Epiclon N-770 (trade name, manufactured by DIC), EPPN-201 and EPPN-202 (both trade names, (Manufactured by Nippon Kayaku Co., Ltd.).

Examples of the cresol novolac-type epoxy compound include jER180S75 (trade name, manufactured by Mitsubishi Chemical Corporation), YDCN-701, YDCN-702 (both products) Name, manufactured by Tohto Kasei Co., Ltd.), Epiclon N-665, Epiclon N-695 (both trade names, manufactured by DIC Corporation), EOCN-102S, EOCN- 103S, EOCN-104S, EOCN-1020, EOCN-1025 and EOCN-1027 (all are trade names, manufactured by Nippon Kayaku Co., Ltd.).

Examples of the bisphenol A novolac epoxy compound include jER157S70 (trade name, manufactured by Mitsubishi Chemical Corporation), and Epiclon N-880 (trade name, manufactured by DIC Corporation) .

Examples of the naphthalene skeleton-containing epoxy compound include: Epiclon HP-4032, Epiclon HP-4700, and Epiclon HP-4770 (both trade names, DIC) ) (Product), and NC-7000 (trade name, manufactured by Nippon Kayaku Co., Ltd.).

Examples of the aromatic polyglycidyl ether compound include hydroquinone diglycidyl ether (the following formula EP-1), catechol diglycidyl ether (the following formula EP-2), and resorcinol Glycidyl ether (EP-3 below), 2- [4- (2,3-epoxypropoxy) phenyl] -2- [4- [1,1-bis [4-([2 , 3-epoxypropoxy] phenyl)] ethyl] phenyl] propane (EP-4 below), tris (4-glycidyloxyphenyl) methane (EP-5 below) ), JER1031S, jER1032H60 (both trade names, manufactured by Mitsubishi Chemical Corporation), TACTIX-742 (trade names, manufactured by The Dow Chemical Company), Denacol EX-201 ( Trade names, manufactured by Nagase ChemteX (stock), DPPN-503, DPPN-502H, DPPN-501H, NC6000 (all product names, manufactured by Nippon Kayaku Co., Ltd.), Techmore VG3101L (trade name, manufactured by Mitsui Chemicals Co., Ltd.), represented by the following formula EP-6 And a compound represented by the following formula FP-7.

Examples of the dicyclopentadiene phenol type epoxy compound include TACTIX-556 (trade name, manufactured by The Dow Chemical Company), and Epiclon HP-7200 (trade name, Diison) (DIC) (shares).

Examples of the alicyclic diglycidyl ether compound include a cyclohexanedimethanol diglycidyl ether compound, and Ricaresin DME-100 (quote Product name, manufactured by Shinnippon Physicochemical Co., Ltd.).

Examples of the aliphatic polyglycidyl ether compound include ethylene glycol diglycidyl ether (the following formula EP-8), diethylene glycol diglycidyl ether (the following formula EP-9), and polyethylene glycol diglycidyl. Glyceryl ether, propylene glycol diglycidyl ether (EP-10 below), tripropylene glycol diglycidyl ether (EP-11 below), polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether (hereinafter EP-12), 1,4-butanediol diglycidyl ether (the following formula EP-13), 1,6-hexanediol diglycidyl ether (the following formula EP-14), dibromoneopenta Diethylene glycol diglycidyl ether (EP-15 below), Denacol EX-810, Denacol EX-851, Denacol EX-8301, Dena Denacol EX-911, Denacol EX-920, Denacol EX-931, Denacol EX-211, Denacol EX -212, Denacol EX-313 (both trade names, manufactured by Nagase ChemteX), DD-503 (trade name, manufactured by ADEKA) , Ricaresin W-100 (trade name, manufactured by Shinnippon Ricoh Co., Ltd.), 1,3,5,6-tetraglycidyl-2,4-hexanedione Alcohol (EP-16 below), glycerol polyglycidyl ether, sorbitol polyglycidyl ether, trimethylolpropane polyglycidyl ether, pentaerythritol polyglycidyl ether, Denacol EX-313 , Denacol EX-611, Denacol EX-321 and Denacol EX-411 (all are trade names, manufactured by Nagase ChemteX) ).

Examples of the polythioether-type diglycidyl ether compound include FLDP-50 and FLDP-60 (both are trade names, manufactured by Toray Thiokol (Stock)).

Examples of the biphenol type epoxy compound include: YX-4000, YL-6121H (both are trade names, manufactured by Mitsubishi Chemical Corporation), NC-3000P and NC-3000S (both trade names, Nippon Kayaku Co., Ltd.) Manufacturing).

Examples of the diglycidyl compound include diglycidyl terephthalate (EP-17 below), diglycidyl phthalate (EP-18 below), and bis (2 -Methyloxetylmethyl) ester (EP-19 below), diglycidyl hexahydrophthalate (EP-20 below), and compound represented by EP-21 below A compound represented by the following formula EP-22, and a compound represented by the following formula EP-23.

Examples of the glycidyl epoxy compound include jER871, jER872 (Both trade names, manufactured by Mitsubishi Chemical Corporation), Epiclon 200, Epiclon 400 (both trade names, manufactured by DIC), Dana Kaul (Denacol) EX-711 and Denacol EX-721 (both are trade names, manufactured by Nagase ChemteX).

Examples of the polyglycidylamine compound include N, N-diglycidylaniline (the following formula EP-24), N, N-diglycidyl-o-toluidine (the following formula EP-25), N , N-diglycidyl-m-toluidine (EP-26 below), N, N-diglycidyl-2,4,6-tribromoaniline (EP-27 below), 3- ( N, N-diglycidyl) aminopropyltrimethoxysilane (the following formula EP-28), N, N, O-triglycidyl-p-aminophenol (the following formula EP-29), N, N, O-triglycidyl-m-aminophenol (formula EP-30 below), N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenyl Methane (the following formula EP-31), N, N, N ', N'-tetraglycidyl-m-xylylenediamine (TETRAD-X (trade name, manufactured by Mitsubishi Gas Chemical Co., Ltd.), the following formula EP-32), 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane (TETRAD-C (trade name, manufactured by Mitsubishi Gas Chemical Co., Ltd.), the following formula EP-33 ), 1,4-bis (N, N-diglycidylaminomethyl) cyclohexane (the following formula EP-34), 1,3-bis (N, N-diglycidylamino) Cyclohexane (the following formula EP-35), 1,4-bis (N, N-diglycidylamino) cyclohexane (the following formula EP-36), 1,3-bis (N, N -Dishrinking Oleylamino) benzene (formula EP-37), 1,4-bis (N, N-diglycidylamino) benzene (formula EP-38), 2,6-bis (N, N-diglycidylaminomethyl) bicyclo [2.2.1] heptane (EP-39 below), N, N, N ', N'-tetraglycidyl-4,4'-diamine Dicyclohexylmethane (EP-40 below), 2,2'-dimethyl- (N, N, N ', N'-tetraglycidyl) -4,4'-diaminobiphenyl base (The following formula EP-41), N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenyl ether (the following formula EP-42), 1, 3, 5 -Tris (4- (N, N-diglycidyl) aminophenoxy) benzene (EP-43 below), 2,4,4'-tris (N, N-diglycidylamino) ) Diphenyl ether (the following formula EP-44), tris (4- (N, N-diglycidyl) aminophenyl) methane (the following formula EP-45), 3,4,3 ', 4'-tetrakis (N, N-diglycidylamino) biphenyl (EP-46 below), 3,4,3 ', 4'-tetrakis (N, N-diglycidylamino) A diphenyl ether (the following formula EP-47), a compound represented by the following formula EP-48, and a compound represented by the following formula EP-49.

Examples of the homopolymer of the oxetanyl group-containing monomer include polyglycidyl methacrylate. Examples of the copolymer of a monomer having an oxetanyl group include an N-phenylcis butylene diimide-glycidyl methacrylate copolymer, and an N-cyclohexyl cis butylene diimide-formaldehyde. Glycidyl acrylate copolymer, benzyl methacrylate-glycidyl methacrylate copolymer, butyl methacrylate-glycidyl methacrylate copolymer, 2-hydroxyethyl methacrylate-methyl Glycidyl acrylate copolymer, (3-ethyl-3-oxetanyl) methyl methacrylate-glycidyl methacrylate copolymer, and styrene-glycidyl methacrylate copolymer.

Examples of the oxetanyl-containing monomer include glycidyl (meth) acrylate, 3,4-epoxycyclohexyl (meth) acrylate, and methyl glycidyl (meth) acrylate.

Oxetanyl group in copolymers of oxetanyl group-containing monomers Examples of the monomer other than the monomers include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, and butyl (meth) acrylate Ester, isobutyl (meth) acrylate, third butyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, styrene, methylstyrene, chloromethylstyrene, (3-ethyl-3-oxetanyl) methyl (meth) acrylate, N-ring Hexyl cis butene difluorene imine, and N-phenylcis butene difluorene imine.

Examples of the glycidyl isocyanurate include 1,3,5-triglycidyl-1,3,5-triazine-2,4,6- (1H, 3H, 5H) -trione (described below) EP-50), 1,3-diglycidyl-5-allyl-1,3,5-triazine-2,4,6- (1H, 3H, 5H) -trione (formula EP-51), and glycidyl isocyanurate type epoxy resin.

Examples of the chain aliphatic epoxy compound include epoxidized polybutadiene and Epolead PB3600 (trade name, manufactured by Daicel Co., Ltd.).

Examples of the cyclic aliphatic epoxy compound include 3,4-epoxycyclohexenylmethyl-3 ', 4'-epoxycyclohexenecarboxylate (Celloxide 2021). (Manufactured by Daicel), the following formula EP-52), 2-methyl-3,4-epoxycyclohexylmethyl-2'-methyl-3 ', 4'-cyclo Oxycyclohexylcarboxylate (EP-53), 2,3-epoxycyclopentane-2 ', 3'-epoxycyclopentane ether (EP-54), ε -Caprolactone modified 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexane carboxylate, 1: 8,9-diepoxy limonene (Siro Cell oxide 3000 (trade name, manufactured by Daicel), the compound represented by the following formula EP-55), the compound represented by the following formula EP-56, CY-175, CY-177, CY- 179 (both trade names, manufactured by The Ciba-Geigy Chemical Corp. (available from Japan Huntsman Co., Ltd.)), EHPD-3150 (trade name, Daicel ( Daicel) and cyclic aliphatic epoxy resin.

The epoxy compound is preferably one or more of a polyglycidylamine compound, a bisphenol A novolac epoxy compound, a cresol novolac epoxy compound, and a cyclic aliphatic epoxy compound, and more preferably N, N, N ', N'-tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N', N '- Tetraglycidyl-4,4'-diaminodiphenylmethane, trade name "Techmore VG3101L", 3,4-epoxycyclohexenylmethyl-3 ', 4'- Epoxy cyclohexene carboxylate, N-phenylcis butylene diimide-glycidyl methacrylate copolymer, N, N, O-triglycidyl-p-aminophenol, bisphenol A One or more of a novolac epoxy compound and a cresol novolac epoxy compound.

Examples of the polymer compound include polymer compounds that are soluble in organic solvents. Adding such a polymer compound to the liquid crystal alignment agent of the present invention is preferable from the viewpoint of controlling the electrical characteristics or alignment properties of the liquid crystal alignment film to be formed. Examples of the polymer compound include polyamide, polyurethane, polyurea, polyester, polyepoxide, polyester polyol, silicone-modified polyurethane, and silicone-modified polyurethane. Polyester, polyamidoamine, polysiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly (styrene-phenylmaleimide diimide) derivative, poly (methyl )Acrylate. It may be one type, or two or more types. Among these compounds, polysiloxane is preferred.

Other low-molecular compounds include, for example: 1) a surfactant that meets the above-mentioned purpose when the coating property is desired to be improved; 2) an antistatic agent when the antistatic property must be improved; 3) a good adhesion to the substrate A silane coupling agent or a titanium-based coupling agent; 4) a fluorene imidization catalyst in the case of fluorene imidization at a low temperature.

Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, and N- ( (2-aminoethyl) -3-aminopropylmethyltrimethoxysilane, p-aminophenyltrimethoxysilane, p-aminophenyltriethoxysilane, m-aminophenyltrimethoxysilane Silane, M-aminophenyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyl Glyceryloxypropylmethyldimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane , 3-mercaptopropyltrimethoxysilane, N- (1,3-dimethylbutylene) -3- (triethoxysilyl) -1-propylamine, and N, N'-bis [ 3- (trimethoxysilyl) propyl] ethylenediamine. A preferred silane coupling agent is 3-aminopropyltriethoxysilane.

Examples of the imidization catalyst include aliphatic amines such as trimethylamine, triethylamine, tripropylamine, and tributylamine; N, N-dimethylaniline, N, N-diethyl Aromatic amines such as aniline, methyl-substituted aniline, hydroxy-substituted aniline; pyridine, methyl-substituted pyridine, hydroxyl-substituted pyridine, quinoline, methyl-substituted quinoline, hydroxyl-substituted Cyclic amines such as quinoline, isoquinoline, methyl-substituted isoquinoline, hydroxy-substituted isoquinoline, imidazole, methyl-substituted imidazole, and hydroxyl-substituted imidazole. The amidine imidization catalyst is preferably selected from the group consisting of N, N-dimethylaniline, o-hydroxyaniline, m-hydroxyaniline, p-hydroxyaniline, o-hydroxypyridine, m-hydroxypyridine, p-hydroxypyridine, and isoquine One or two or more of them.

The addition amount of the silane coupling agent is usually 0% to 20% by weight, and preferably 0.1% to 10% by weight, based on the total weight of the polyamic acid or its derivative.

Generally, the addition amount of the fluorene imidization catalyst is 0.01 equivalent to 5 equivalents, and preferably 0.05 equivalent to 3 equivalents relative to the carbonyl group of the polyamic acid or its derivative.

The amount of other additives to be added varies depending on the purpose, but it is usually 0% to 100% by weight, preferably 0.1% by weight, based on the total weight of the polyamic acid or its derivative. Amount% ~ 50% by weight.

The polyamic acid or a derivative thereof of the present invention can be produced in the same manner as a known polyamino acid or a derivative thereof for forming a film of a polyimide. The total added amount of the tetracarboxylic dianhydride is preferably set to be approximately equal to the total molar number of the diamine (the molar ratio is about 0.9 to 1.1).

The molecular weight of the polyamidic acid or its derivative contained in the liquid crystal alignment agent of the present invention is preferably 7,000 to 500,000, more preferably 10,000 to 200,000 in terms of polystyrene equivalent weight average molecular weight (Mw). The molecular weight of the said polyamic acid or its derivative can be calculated | required by the measurement of Gel Permeation Chromatography (GPC).

The polyamidic acid or its derivative of the present invention can be confirmed by analyzing the solid content obtained by precipitating with a large amount of a poor solvent by using infrared (IR) or nuclear magnetic resonance (NMR). presence. In addition, by using Gas Chromatography (GC), High Performance Liquid Chromatography (HPLC) or Gas Chromatography Mass Spectrometry (GC-MS), The monomer used was confirmed by analyzing an extract obtained from an organic solvent with an aqueous solution of a strong base such as KOH or NaOH, and a decomposition product of the polyamic acid or its derivative.

The concentration of the polyamidic acid in the alignment agent of the present invention is preferably 0.1% to 40% by weight. When this alignment agent is applied to a substrate, in order to adjust the film thickness, an operation of diluting the polyamic acid contained in the solvent may be required in advance.

The concentration of the solid content in the alignment agent of the present invention is not particularly limited, as long as the optimum value is selected in accordance with various coating methods described below. In general, in order to suppress unevenness, pinholes, and the like during coating, it is preferably 0.1% to 30% by weight, and more preferably 1% to 10% by weight relative to the weight of the varnish.

The preferable range of the viscosity of the liquid crystal alignment agent of the present invention varies depending on the coating method, the concentration of the polyamic acid or its derivative, the type of the polyamino acid or its derivative used, the type and ratio of the solvent. In the case of coating using the inkjet coating device which is the subject of the present invention, it is preferably 5 mPa. s ~ 50mPa. s. In order to obtain a sufficient film thickness, it is preferably 5 mPa. Above s, in order not to cause uneven printing, 50 mPa is preferred. s or less. More preferably, it is 5mPa. s ~ 20mPa. The range of s. In the case of coating by other methods, for example, 5 mPa in the case of coating by a printer. s ~ 100mPa. s (more preferably 10 mPa.s to 80 mPa.s). In the case of coating by spin coating, it is preferably 5 mPa. s ~ 200mPa. s (more preferably 10 mPa.s to 100 mPa.s). The viscosity of the liquid crystal alignment agent is measured by a rotational viscosity measurement method, for example, using a rotational viscosity meter (TVE-20L type manufactured by Toki Sangyo) to measure (measurement temperature: 25 ° C).

The liquid crystal alignment film of the present invention will be described in detail. The liquid crystal alignment film of the present invention is a film formed by heating the coating film of the liquid crystal alignment agent of the present invention. The liquid crystal alignment film of the present invention can be obtained by a general method for producing a liquid crystal alignment film from a liquid crystal alignment agent. For example, the liquid crystal alignment film of the present invention can be obtained by a step of forming a coating film of the liquid crystal alignment agent of the present invention, a step of heating and drying, and a step of heating and calcining. For the liquid crystal alignment film of the present invention, as needed As described later, the film obtained through the heat drying step and the heat calcination step may be subjected to a rubbing treatment to impart anisotropy. Alternatively, if necessary, anisotropy may be imparted by irradiating light after the coating step, heating and drying step, or irradiating light after the heating and calcining step. It can also be used as a liquid crystal alignment film for VA that has not been subjected to a rubbing treatment.

The coating film can be formed by coating the liquid crystal alignment agent of the present invention on a substrate in a liquid crystal display element in the same manner as in the production of a normal liquid crystal alignment film. The substrate may include electrodes such as indium tin oxide (ITO), indium zinc oxide (In ₂ O ₃ -ZnO, IZO), and indium gallium zinc oxide (In-Ga-ZnO ₄ , IGZO) electrodes. Or glass substrates such as color filters.

The method of applying the liquid crystal alignment agent to the substrate is preferably an inkjet method. In addition, generally known methods such as a spinner method, a printing method, a dipping method, and a dropping method can also be applied.

The heating and drying step is generally known as a method of performing a heat treatment in an oven or an infrared oven, a method of performing a heat treatment on a hot plate, and the like. The heat-drying step is preferably performed at a temperature within a range in which the solvent can be evaporated, and more preferably, it is performed at a temperature that is relatively low relative to the temperature in the heat-calcination step. Specifically, the heating and drying temperature is preferably in a range of 30 ° C to 150 ° C, and particularly preferably in a range of 50 ° C to 120 ° C.

The heating and calcining step can be used to make the polyamidic acid or its derivative appear dehydrated. The ring closure reaction is carried out under the conditions necessary. The firing of the coating film is generally known as a method of performing a heat treatment in an oven or an infrared furnace, a method of performing a heat treatment on a hot plate, and the like. These methods can be similarly applied to the present invention. Usually better It is performed at a temperature of about 100 ° C to 300 ° C for 1 minute to 3 hours, more preferably 120 ° C to 280 ° C, and even more preferably 150 ° C to 250 ° C.

In the method for forming a liquid crystal alignment film of the present invention, in order to align liquid crystals in one direction with respect to a horizontal and / or vertical direction, a method for imparting anisotropy to the alignment film may be a known method such as a rubbing method or an optical alignment method. Formation method.

The liquid crystal alignment film of the present invention using a rubbing method may be subjected to a step of applying the liquid crystal alignment agent of the present invention to a substrate, a step of heating and drying the substrate coated with the alignment agent, a step of heating and calcining the film, And a step of rubbing the film.

The rubbing treatment can be performed in the same manner as the rubbing treatment generally used for performing the alignment treatment of the liquid crystal alignment film, as long as it is a condition for obtaining a sufficient delay in the liquid crystal alignment film of the present invention. The preferred conditions are: a gross press-in amount of 0.2 mm to 0.8 mm, a platform moving speed of 5 mm / sec to 250 mm / sec, and a roller rotation speed of 500 rpm to 2,000 rpm.

A method for forming a liquid crystal alignment film of the present invention using a photo-alignment method will be described in detail. After the liquid crystal alignment film of the present invention using the photo-alignment method is heated and dried, the coating film can be anisotropic by being irradiated with linearly polarized light or no polarized light, and the film can be heated. Formed by calcination. Alternatively, the coating film may be formed by heat-drying and heat-calcining, and may be irradiated with linearly polarized light or non-polarized light. In terms of alignment, the radiation irradiation step is preferably performed before the heating and calcining step.

Furthermore, in order to improve the liquid crystal alignment ability of the liquid crystal alignment film, The coating film is heated while being irradiated with linearly polarized light or non-polarized light. The radiation may be performed by a step of heating and drying the coating film or a step of heating and calcining, or may be performed between the step of heating and drying and the step of heating and calcining. The heating and drying temperature in this step is preferably in a range of 30 ° C to 150 ° C, and more preferably in a range of 50 ° C to 120 ° C. The heating and calcining temperature in this step is preferably in the range of 30 ° C to 300 ° C, and more preferably in the range of 50 ° C to 250 ° C.

As the radiation, for example, ultraviolet rays or visible light including light having a wavelength of 150 nm to 800 nm can be used, and ultraviolet rays including light having a wavelength of 300 nm to 400 nm are preferably used. In addition, linearly polarized or unpolarized light can be used. The light is not particularly limited as long as it can impart liquid crystal alignment ability to the coating film, and when it is intended to exhibit strong alignment control power to the liquid crystal, linearly polarized light is preferred.

The liquid crystal alignment film of the present invention can also exhibit high liquid crystal alignment ability under low energy light irradiation. The amount of irradiation of linearly polarized radiation irradiation step is preferably ^{0.05J / cm 2 ~ 20J / cm} 2, more preferably ^{0.5J / cm 2 ~ 10J / cm} 2. The wavelength of the linearly polarized light is preferably 200 nm to 400 nm, and more preferably 300 nm to 400 nm. The linearly polarized light has no particular limitation on the irradiation angle of the film surface. When it is intended to exhibit strong alignment control of the liquid crystal, from the viewpoint of shortening the alignment processing time, it is preferable that May be vertical. In addition, the liquid crystal alignment film of the present invention can align the liquid crystal in a direction perpendicular to the polarization direction of the linearly polarized light by irradiating the linearly polarized light.

When the pretilt angle is to be expressed, the light irradiated to the film may be linearly polarized light or non-polarized light as described above. In the case where a pretilt angle is to be exhibited, the irradiation amount of light irradiated to the film is preferably 0.05 J / cm ² to 20 J / cm ² , particularly preferably 0.5 J / cm ² to 10 J / cm ² , and its wavelength It is preferably 250 nm to 400 nm, and particularly preferably 300 nm to 380 nm. In the case where the pretilt angle is to be expressed, the irradiation angle of the light irradiated to the film on the surface of the film is not particularly limited, and from the viewpoint of shortening the alignment processing time, it is preferably 30 degrees to 60 degrees.

The light source used in the step of radiating linearly polarized light or unpolarized light can be used without limitation: ultra-high pressure mercury lamp, high pressure mercury lamp, low pressure mercury lamp, deep ultraviolet lamp, halogen lamp, metal halide lamp, high power metal Halide lamp, xenon lamp, mercury xenon lamp, excimer lamp, KrF excimer laser, fluorescent lamp, light emitting diode (LED) lamp, sodium lamp, microwave excitation electrodeless lamp, etc.

The liquid crystal alignment film of the present invention is appropriately obtained by a method including steps other than the above steps. For example, although the liquid crystal alignment film of the present invention does not require a step of washing the film after calcined or irradiated with a washing liquid, a washing step may be provided for consideration of other steps.

Examples of the washing method using a washing liquid include brush washing, jet spray, steam washing, and ultrasonic washing. These methods can be performed individually or in combination. Washing liquid can be used: pure water, or various alcohols such as methanol, ethanol, isopropanol, aromatic hydrocarbons such as benzene, toluene, xylene, halogen solvents such as dichloromethane, ketones such as acetone, methyl ethyl ketone, etc. Classes, but not limited to those. Of course, these washing liquids are those which have been sufficiently purified and have few impurities. Such a washing method can also be applied to the washing step in the formation of the liquid crystal alignment film of the present invention.

In order to improve the liquid crystal alignment ability of the liquid crystal alignment film of the present invention, an annealing treatment using heat or light may be used before and after the heating and calcining step, before and after the rubbing step, or before and after irradiation with polarized or unpolarized radiation. In this annealing treatment, the annealing temperature is 30 ° C to 180 ° C, preferably 50 ° C to 150 ° C, and the time is preferably 1 minute to 2 hours. Examples of the annealing light used in the annealing process include UV lamps, fluorescent lamps, and LED lamps. Light irradiation amount is preferably ^{0.3J / cm 2 ~ 10J / cm} 2.

The thickness of the liquid crystal alignment film of the present invention is not particularly limited, but is preferably 10 nm to 300 nm, and more preferably 30 nm to 150 nm. The film thickness of the liquid crystal alignment film of the present invention can be measured by a known film thickness measuring device such as a profiler or an ellipsometer.

The liquid crystal alignment film of the present invention is characterized by having a particularly large alignment anisotropy. The magnitude of the anisotropy as described above can be evaluated by a method using polarized IR described in Japanese Patent Laid-Open No. 2005-275364 and the like. In addition, as shown in the following examples, evaluation can also be performed by a method using an elliptically polarized method. Specifically, the retardation value of the liquid crystal alignment film can be measured using a spectroscopic ellipsometer. The retardation value of the film increases in proportion to the degree of alignment of the polymer backbone. That is, it is considered that a film having a large retardation value has a large degree of alignment, and when used as a liquid crystal alignment film, an alignment film having greater anisotropy has a large alignment control force on a liquid crystal composition.

The liquid crystal alignment film of the present invention can be used for alignment control of an optical compensation material or all other liquid crystal materials in addition to the alignment application of a liquid crystal composition for a liquid crystal display. In addition, since the alignment film of the present invention has a large anisotropy, it can be used alone as an optical compensation material.

The liquid crystal display element of the present invention will be described in detail.

The present invention provides a liquid crystal display element including a pair of substrates disposed opposite to each other, an electrode formed on one or both of the opposing surfaces of the pair of substrates, and an electrode formed on each of the pair of substrates. The liquid crystal alignment film on the facing surface and the liquid crystal layer formed between the pair of substrates, and the liquid crystal alignment film is an alignment film of the present invention.

The electrode is not particularly limited as long as it is an electrode formed on one surface of the substrate. Examples of such electrodes include ITO and a vapor-deposited film of a metal. In addition, the electrode may be formed on the entire surface of one surface of the substrate, and may be formed into a desired shape patterned, for example. Examples of the desired shape of the electrode include a comb type or a zigzag structure. The electrode may be formed on one of the pair of substrates, or may be formed on two substrates. The form of the electrodes varies depending on the type of the liquid crystal display element. For example, in the case of an IPS type liquid crystal display element, an electrode is arranged on one of the pair of substrates, and in the case of other liquid crystal display elements, the Electrodes are arranged on two pieces of a pair of substrates. The liquid crystal alignment film is formed on the substrate or the electrode.

The liquid crystal layer is formed in such a manner that a liquid crystal composition is sandwiched between the pair of substrates facing each other with a liquid crystal alignment film formed thereon. In the formation of the liquid crystal layer, a spacer such as fine particles or a resin sheet that is interposed between the pair of substrates and is formed at an appropriate interval may be used as necessary.

The liquid crystal composition is not particularly limited, and various liquid crystal compositions having a positive or negative dielectric anisotropy can be used. Among the preferred liquid crystal compositions with a positive dielectric anisotropy are: Japanese Patent 3086228, Japanese Patent 2635435, Japanese Patent Special Table Flat 5-501735, Japanese Patent Laid-Open No. 8-157826, Japanese Patent Laid-Open No. 8-231960, Japanese Patent Laid-Open No. 9-241644 (EP885272A1), Japanese Patent Laid-Open No. 9-302346 (EP806466A1), Japanese Patent Laid-Open No. 8-199168 ( EP722998A1), Japanese Patent Laid-Open No. 9-235552, Japanese Patent Laid-Open No. 9-255956, Japanese Patent Laid-Open No. 9-241643 (EP885271A1), Japanese Patent Laid-Open No. 10-204016 (EP844229A1), Japanese Patent Laid-Open No. 10-204436, Japan The liquid crystal composition disclosed in Japanese Patent Laid-Open No. 10-231482, Japanese Patent Laid-Open No. 2000-087040, Japanese Patent Laid-Open No. 2001-48822, and the like.

It does not matter if one or more optically active compounds are added to a liquid crystal composition having a dielectric anisotropy of positive or negative.

A liquid crystal composition having a negative dielectric anisotropy will be described. Examples of the negative dielectric anisotropic liquid crystal composition include a composition containing at least one liquid crystal compound selected from the group of liquid crystal compounds represented by the following formula (NL-1) as a first component.

Here, R ^1a and R ^{2a are} independently an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or a carbon number 2 in which at least one hydrogen is replaced by fluorine. Alkenyl of ~ 12, ring A ² and ring B ^{2 are} independently 1,4-cyclohexyl, tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl , 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene , 2-fluoro-3-chloro-1,4-phenylene, 2,3-difluoro-6-methyl-1,4-phenylene, 2,6-naphthalenediyl, or 7,8- Difluorochroman-2,6-diyl, here, at least one of ring A ² and ring B ² is 2,3-difluoro-1,4-phenylene, 2-fluoro-3-chloro -1,4-phenylene, 2,3-difluoro-6-methyl-1,4-phenylene, or 7,8-difluorochromogen-2,6-diyl, Z ^{1 is} independent Ground is a single bond,-(CH ₂ ) _2- , -CH ₂ O-, -COO- or -CF ₂ O-, j is 1, 2 or 3, and when j is 2 or 3, any two rings A ² may be the same or different, and any two Z ¹ may be the same or different.

In order to improve the dielectric anisotropy, the preferred ring A ² and ring B ² are 2,3-difluoro-1,4-phenylene or tetrahydropyran-2,5-diyl. In order to reduce the viscosity, Preferred ring A ² and ring B ² are 1,4-cyclohexyl.

To increase the dielectric anisotropy, the preferred Z ¹ is -CH ₂ O-, and to reduce the viscosity, the preferred Z ¹ is a single bond.

In order to lower the lower limit temperature, the preferred j is 1, and in order to increase the upper limit temperature, the preferred j is 2.

Specific examples of the liquid crystal compound of the formula (NL-1) include compounds represented by the following formulae (NL-1-1) to (NL-1-32).

Here, R ^1a and R ^{2a are} independently an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or a carbon number 2 in which at least one hydrogen is replaced by fluorine. Alkenyl of ~ 12, ring A ²¹ , ring A ²² , ring A ²³ , ring B ²¹ and ring B ^{22 are} independently 1,4-cyclohexyl or 1,4-phenylene, and Z ¹¹ and Z ^{12 are} independent Ground is a single bond,-(CH ₂ ) _2- , -CH ₂ O-, or -COO-.

In order to improve the stability to ultraviolet rays and heat, etc., preferred R ^1a and R ^2a are alkyl groups having 1 to 12 carbon atoms, or in order to increase the absolute value of dielectric anisotropy, preferred R ^1a and R ^2a are Alkoxy having 1 to 12 carbon atoms.

Preferred alkyl groups are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl or octyl. To reduce viscosity, particularly preferred alkyl groups are ethyl, propyl, butyl, pentyl or heptyl.

Preferred alkoxy groups are methoxy, ethoxy, propoxy, butoxy, pentoxy, hexyloxy or heptyloxy. To reduce viscosity, a particularly preferred alkoxy group is methoxy or ethoxy.

Preferred alkenyl groups are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3 -Pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl or 5-hexenyl. To reduce viscosity, particularly preferred alkenyl is vinyl, 1-propenyl, 3-butenyl or 3-pentenyl. The preferred stereo configuration of -CH = CH- in these alkenyl groups depends on the position of the double bond. In order to reduce the viscosity, etc., such as 1-propenyl, 1-butenyl, 1-pentenyl, 1-hexenyl, Among the alkenyl groups such as 3-pentenyl and 3-hexenyl, the trans configuration is preferred. Among the alkenyl groups such as 2-butenyl, 2-pentenyl, and 2-hexenyl, the cis configuration is preferred. Among these alkenyl groups, linear alkenyl groups are superior to branched alkenyl groups.

Preferred examples of alkenyl in which at least one hydrogen is substituted by fluorine are: 2,2-difluorovinyl, 3,3-difluoro-2-propenyl, 4,4-difluoro-3-butenyl, 5 , 5-difluoro-4-pentenyl and 6,6-difluoro-5-hexenyl. In order to reduce the viscosity, particularly preferred examples are 2,2-difluorovinyl and 4,4-difluoro-3-butenyl.

In order to reduce the viscosity, the preferred ring A ²¹ , ring A ²² , ring A ²³ , ring B ²¹ and ring B ²² are 1,4-cyclohexyl, respectively.

In order to improve the dielectric anisotropy, the preferred Z ¹¹ and Z ¹² are -CH ₂ O-. In order to reduce the viscosity, the preferred Z ¹¹ and Z ¹² are single bonds.

As the first component, the preferred compound (NL-1) of the liquid crystal composition having negative dielectric anisotropy is the compound (NL-1-1), the compound (NL-1-4), or the compound (NL- 1-7) or compound (NL-1-32).

Preferable examples of the liquid crystal composition having negative dielectric anisotropy include Japanese Patent Laid-Open No. Sho 57-114532, Japanese Patent Laid-Open No. 2-4725, Japanese Patent Laid-Open No. 4-224885, and Japanese Patent Laid-Open No. 8- 40953, Japanese Patent Laid-Open No. 8-104869, Japanese Patent Laid-Open No. 10-168076, Japanese Patent Laid-Open No. 10-168453, Japanese Patent Laid-Open No. 10-236989, Japanese Patent Laid-Open No. 10-236990, Japanese Patent Laid-Open No. 10-236992, Japanese Patent Laid-Open No. 10-236993, Japanese Patent Laid-Open No. 10-236994, Japanese Patent Laid-Open No. 10-237000, Japanese Patent Laid-Open No. 10-237004, Japanese Patent Laid-Open No. 10-237024, Japanese Patent Laid-Open No. 10-237035, Japanese Patent Laid-Open No. 10-237075, Japanese Patent Laid-Open No. 10-237076, Japanese Patent Laid-Open No. 10-237448 (EP967261A1), Japanese Patent Laid-Open No. 10-287874, Japanese Patent No. Kaiping 10-287875, Japanese Patent Laid-Open No. 10-291945, Japanese Patent Laid-Open No. 11-029581, Japanese Patent Laid-Open No. 11-080049, Japanese Patent Laid-Open No. 2000-256307, Japanese Patent Laid-Open No. 2001-019965, Japanese Patent Laid-Open No. 2001 -072626, Japanese Patent Laid-Open No. 2001-192657, Japanese Patent Laid-Open No. 2010-037428, International Publication No. 2011/024666, International Publication No. 2010/072370, Japanese Patent No. 2010-537010, Japanese Patent No. 2012-077201, Japanese Patent No. The liquid crystal composition disclosed in 2009-084362 and the like.

In addition, for example, from the viewpoint of improving the alignment, the liquid crystal composition used in the device of the present invention may be further added with an additive. Such additives include photopolymerizable monomers, optically active compounds, antioxidants, ultraviolet absorbers, pigments, defoamers, polymerization initiators, polymerization inhibitors, and the like.

For the purpose of improving the alignment of the liquid crystal, the optimal structure of the photopolymerizable monomer or oligomer may include the structures of (PM-1-1) to (PM-1-6).

In order to exhibit the effect of determining the oblique direction of the liquid crystal after polymerization, the photopolymerizable monomer or oligomer is preferably 0.01% by weight or more. In addition, in order to make the alignment effect of the polymer after polymerization appropriate, or to prevent unreacted monomers or oligomers from dissolving in the liquid crystal after ultraviolet irradiation, it is preferably 30% by weight or less.

An optically active compound is mixed in the composition for the purpose of giving a twist angle to the helical structure of the liquid crystal. Examples of such compounds are compound (PAC-1-1) to compound (PAC-1-4).

The preferable ratio of an optically active compound is 5 weight% or less. A particularly preferred ratio is in the range of 0.01% by weight to 2% by weight.

In order to prevent the decrease in specific resistance caused by heating in the atmosphere, or to maintain a large voltage holding ratio not only at room temperature but also at high temperatures after using the device for a long time, an antioxidant is mixed in the liquid crystal组合 物。 Composition.

Preferred examples of the antioxidant are compounds (AO-1) and the like in which w is an integer of 1 to 10. In compound (AO-1), preferable w is 1, 3, 5, 7, or 9. A particularly preferred w is 1 or 7. The compound (AO-1) in which w is 1 is effective in preventing a decrease in specific resistance due to heating in the atmosphere because of its high volatility. w is 7 Because of its low volatility, the compound (AO-1) is effective for maintaining a large voltage holding ratio not only at room temperature but also at high temperatures after long-term use of the device. In order to obtain the effect, a preferred ratio of the antioxidant is 50 ppm or more, and in order not to lower the upper limit temperature, or not to raise the lower limit temperature, the preferred ratio of the antioxidant is 600 ppm or less. A particularly preferred ratio is in the range of 100 ppm to 300 ppm.

Preferred examples of the ultraviolet absorber include benzophenone derivatives, benzoate derivatives, and triazole derivatives. In addition, a light stabilizer such as an amine having a steric hindrance is also preferable. In order to obtain the effect, the preferred ratio of these absorbers or stabilizers is 50 ppm or more. In order not to lower the upper limit temperature, or to not raise the lower limit temperature, the preferred ratio of these absorbers or stabilizers is 10,000 ppm or less. A particularly preferred ratio is in the range of 100 ppm to 10,000 ppm.

In order to be suitable for an element of a guest host (GH) mode, a dichroic dye such as an azo pigment or an anthraquinone pigment is mixed in the composition. A preferable ratio of the pigment is in a range of 0.01% by weight to 10% by weight.

In order to prevent foaming, a defoamer such as dimethyl silicone oil and methylphenyl silicone oil is mixed in the composition. In order to obtain the above effect, a preferable ratio of the defoaming agent is 1 ppm or more, and in order to prevent display failure, a preferable ratio of the defoaming agent is 1000 ppm or less. A particularly preferred ratio is in the range of 1 ppm to 500 ppm.

In order to be suitable for a device having a polymer sustained alignment (PSA) mode, a polymerizable compound can be mixed into the composition. Preferred examples of the polymerizable compound are acrylate, methacrylate, vinyl compound, vinyloxy compound, propenyl ether, epoxy compound (oxygen Compounds having a polymerizable group such as heterocyclopropane, oxetane), and vinyl ketone. A particularly preferred example is a derivative of acrylate or methacrylate. Examples of the compound are the compound (PM-2-1) to the compound (PM-2-9). In order to obtain the effect, a preferable ratio of the polymerizable compound is about 0.05% by weight or more, and in order to prevent poor display, a preferable ratio of the polymerizable compound is about 10% by weight or less. A particularly preferred ratio is in the range of about 0.1% by weight to about 2% by weight.

Here, R ^3a , R ^4a , R ^5a , and R ^{6a are} independently acrylfluorenyl or methacrylfluorenyl, and R ^7a and R ^{8a are} independently hydrogen, halogen, or an alkyl group having 1 to 10 carbon atoms, Z ¹³ , Z ¹⁴ , Z ¹⁵ and Z ^{16 are} independently a single bond or an alkylene group having 1 to 12 carbon atoms, at least one -CH ₂ -may be replaced by -O- or -CH = CH-, s, t and u are independently 0, 1, or 2.

As a substance necessary for initiating a chain polymerization reaction easily by generating radicals or ions, a polymerization initiator may be mixed. For example, Irgacure 651 (registered trademark), Irgacure 184 (registered trademark), or Darocure 1173 (registered trademark) as a photopolymerization initiator (Japan Ciba Corporation Limited) (Ciba Japan KK) is suitable for free radical polymerization. The polymerizable compound preferably contains a photopolymerization initiator in a range of 0.1% to 5% by weight. Particularly preferably, the photopolymerization initiator is contained in a range of 1% to 3% by weight.

In the radical polymerization system, it can be mixed with the purpose of stopping the polymerization reaction for the purpose of stopping the polymerization reaction in order to rapidly react with a radical generated by a polymerization initiator or a monomer to change to a stable radical or a neutral compound. Polymerization inhibitor. The polymerization inhibitors are structurally classified into several types. One of them is a self-stable free radical such as tri-p-nitrophenylmethyl, di-p-fluorophenylamine, etc., and the other is changed by easily reacting with a radical existing in a polymerization system. For stable free radicals, nitro, nitroso, amine, and polyhydroxy compounds are represented. Representatives of the latter include hydroquinone and dimethoxybenzene. In order to obtain the above effect, a preferable ratio of the polymerization inhibitor is 5 ppm or more. In order to prevent poor display, a preferable ratio of the polymerization inhibitor is 1000ppm or less. A particularly preferred ratio is in the range of 5 ppm to 500 ppm.

[Example]

Hereinafter, the present invention will be described by way of examples. The evaluation methods and compounds used in the examples are as follows.

<Evaluation method>

1. Weight average molecular weight (Mw)

The weight average molecular weight of the polyamic acid was measured by a GPC method using a 2695 separation module. 2414 differential refractometer (manufactured by Waters), and was determined by polystyrene conversion. Using a mixed solution of phosphoric acid-dimethylformamide (DMF) (phosphoric acid / DMF = 0.6 / 100: weight ratio), the obtained polyamic acid was adjusted so that the polyamic acid concentration became about 2% by weight. Dilute. The column was measured using HSPgel RT MB-M (manufactured by Waters), the mixed solution was used as a developing agent, and the column temperature was 50 ° C. and the flow rate was 0.40 mL / min. The standard polystyrene is TSK standard polystyrene manufactured by Tosoh Corporation.

2. Ink jetting

The inkjet device DMP-2831 manufactured by Fujifilm Dimatix was used for continuous ejection for 60 minutes. Every 42 microseconds, a camera was used to take pictures of droplets ejected from five nozzles projected on the monitor, and confirmed. A liquid crystal alignment agent capable of continuously ejecting liquid droplets having a uniform size as shown in FIG. 1 for 60 minutes was considered acceptable. Will cause nozzle clogging, as shown in Figure 2, ink accumulation near the nozzle (no ejection caused by nozzle clogging 4), or oblique direction observed The case of the ejection phenomenon (inclined ejection 5 due to nozzle clogging) was regarded as unsatisfactory.

Nozzle: DMC-11610 (Number of nozzles: 16 droplets 10pL)

Nozzle temperature: 28 ℃

Applied voltage: 22V

Frequency: 10kHz

3. In-plane streak unevenness and edge linearity in inkjet printing

The inkjet device EB100XY100 manufactured by Konica Minolta was used to confirm the in-plane observation of the alignment film (coating film 6) coated on the substrate 7 with ITO and the edge of the microscope. Level 8. As shown in FIG. 3, the liquid crystal alignment agent whose unevenness of the edge of the coating film was 0.2 mm or less was considered acceptable. In FIG. 4, the unevenness of the edge is 0.2 mm or more, which is unacceptable.

Nozzle: KM512MH (number of nozzles: 512 droplets 14pL)

Nozzle temperature: 25 ℃

Applied voltage: 19V

Frequency: 709Hz

Resolution: 360dpi

Transport speed: 50mm / sec

Nozzle / glass substrate spacing 28mm

4.Contrast

The contrast of the liquid crystal element described later was evaluated using a luminance meter (YOKOGAWA 3298F). A liquid crystal display device is arranged under a crossed Nicol polarized light microscope, and the device is rotated and fixed to transmit light intensity, That is, the angle at which the brightness becomes the smallest. The value of the brightness in this state is referred to as "black brightness". Then, an arbitrary rectangular wave voltage is applied to the device, and the value at which the brightness is maximized is referred to as "white brightness". The value of this white brightness / black brightness is used as a contrast. When the contrast is less than 2500, it is judged as bad, when it is more than 2500, it is judged as good, and when it is 3000 or more, it is judged as best.

5.AC residual image determination

The brightness-voltage characteristics (B-V characteristics) of the liquid crystal display element described later were measured. Let this be a brightness-voltage characteristic before stress is applied: B (before). Next, after applying an AC of 4.5 V and 60 Hz to the device for 20 minutes, a short circuit was performed for 1 second, and the luminance-voltage characteristic (B-V characteristic) was measured again. This is the brightness-voltage characteristic after stress is applied: B (after). Based on these values, the luminance change rate ΔB (%) is estimated using the following formula (AC1).

ΔB (%) = [B (after) -B (before)] / B (before) (AC1)

These measurements were performed with reference to the pamphlet of International Publication 2000/43833. It can be said that the smaller the value of ΔB (%) at the voltage of 0.75V, the more the generation of AC afterimage can be suppressed, and it is preferably 3.0% or less.

The raw material monomers, solvents, and additives of the polymers used in the examples are shown below.

<Tetracarboxylic dianhydride>

(2): pyromellitic dianhydride

(4): 1,2,3,4-butanetetracarboxylic dianhydride

(10): 1,8-bis (3,4-dicarboxylic acid phenyl) octane dianhydride

(11): 4,4'-oxybisphthalic anhydride

The compounds used in the examples are all unsubstituted.

<Diamine>

DAAB: 4,4'-diaminoazobenzene (compound of formula (I-3))

DDE: 4,4'-diaminodiphenyl ether (unsubstituted compound where X of formula (D-2) is -O-)

APDA: 4,4'-N, N'-bis (4-aminophenyl) piperazine (unsubstituted compound of formula (D-3))

DDBU: 4,4'-diaminodiphenylbutane (unsubstituted compound where X of formula (D-2) is-(CH ₂ ) _4- )

PDA: 1,4-phenylenediamine (formula (D-1))

BABZP3: 4,4 '-((propane-1,3-diylbis (4,1-phenylene)) bis (methylene)) diphenylamine

<Solvent>

NMP: N-methyl-2-pyrrolidone

GBL: γ-butyrolactone

BC: butyl cellosolve

BP: 1-butoxy-2-propanol

EDM: Diethylene glycol ethyl methyl ether

DIBK: Diisobutyl Ketone

DPE: Dipentyl ether

BDM: Diethylene glycol butyl methyl ether

EDP: Diethylene glycol ethyl propyl ether

BDE: Diethylene glycol butyl ether

<Additives>

Add.1: 1,3-bis (4,5-dihydro-2-oxazolyl) benzene

Add.2: 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane

<Synthesis of Polyamic Acid>

[Synthesis example A-1]

In a 200 mL brown four-necked flask equipped with a thermometer, a stirrer, a raw material input port, and a nitrogen inlet port, 1.8434 g of DAAB, 0.2087 g of DDBU, 0.0259 g of APDA, and 54.0 g of dehydrated NMP were added, and the mixture was stirred and dissolved under a dry nitrogen stream . Then, 3.9220 g of the tetracarboxylic dianhydride of formula (10) was added, and 20.0 g of dehydrated NMP was further added, and stirring was continued at room temperature for 24 hours. 20.0 g of BP was added to the reaction solution to obtain a polyamidic acid solution having a polymer solid content concentration of 6% by weight. This polyamic acid solution was used as PA-1. The weight average molecular weight of the polyamidic acid contained in PA-1 was 10,300.

[Synthesis example A-2 to Synthesis example A-4]

In addition to changing the composition of tetracarboxylic dianhydride, diamine, and solvent, a polyamine solution (PA-2) to a polyamine solution (solid content of polymer: 6% by weight) was prepared according to Synthesis Example A-1. PA-4). Table 1 shows the composition of raw materials and solvents together with PA-1.

[Synthesis example B-1]

In a 200 mL brown four-necked flask equipped with a thermometer, a stirrer, a raw material input port and a nitrogen inlet port, 1.8321 g of APDA, 1.3670 g of DDE, and 54.0 g of dehydrated NMP were added, and the mixture was stirred and dissolved under a dry nitrogen stream. Then, 1.0424 g of the tetracarboxylic dianhydride of the formula (2) and 1.7585 g of the tetracarboxylic dianhydride of the formula (4) were added, 20.0 g of dehydrated NMP was further added, and stirring was continued at room temperature for 24 hours. 20.0 g of BP was added to the reaction solution to obtain a polyamidic acid solution having a polymer solid content concentration of 6% by weight. This polyamidic acid solution was referred to as PB-1. The weight average molecular weight of the polyamidic acid contained in PB-1 was 50,000.

[Synthesis example B-2 to Synthesis example B-6]

A polymer solid was prepared according to Synthesis Example B-1 except that the solvent composition was changed. The concentration of the polyamidic acid solution (PB-2) to the polyamidic acid solution (PB-6) is 6% by weight. Table 2 shows the composition of raw materials and solvents together with PB-1.

<Polymer Blend>

[Synthesis example PC-1]

The polymer solid content concentration of the polymer solid content concentration prepared in [A] Synthesis Example A-1 was 6% by weight, and the polymer solid content concentration prepared in [B] Synthesis Example B-1 It is a 6 weight% polyamic acid solution (PB-1), and it mixes with [A] / [B] = 3.0 / 7.0 (weight ratio). This mixed solution was further diluted with a solution of NMP / BP / GBL / EDM / BDM / DIBK, and a polyamic acid solution having a polymer solid content concentration of 4% by weight was used as PC-1. At this time, the composition ratio (weight ratio) of the solvents used in the dilution is: 0.067 g of NMP, 2.667 g of BP, 13.60 g of GBL, 15.00 g of EDM, 1.00 g of BDM, and 1.00 g of DIBK.

[Synthesis example PC-2 to Synthesis example PC-32]

[A] A polyamic acid solution selected from the polyamino acid solution (PA-1) to the polyamino acid solution (PA-4), and [B] containing a polyamino acid solution (PB-1 ) ~ Polyamino acid solution of polyamino acid solution (PB-6) was mixed at a weight ratio [A] / [B], and the polymer solid content concentration was used as the weight% described in Table 3, and was used Dilute with various solvents to prepare polyamidic acid solution (PC-1) to polyamidic acid solution (PC-32). Table 3 shows the composition ratios of the polyamic acid solution and the solvent together with PC-1.

[Synthesis example PD-1]

In a polyamic acid solution (PC-1) having a polymer solid content concentration of 4% by weight, an additive (Add.1) was added at a ratio of 15% by weight relative to the weight of the polymer, and the additive (Add .2) It is added in a proportion of 10% by weight based on the weight of the polymer. The obtained polyamic acid solution was used as PD-1.

[Synthesis example PD-2]

In a polyamic acid solution (PC-23) having a polymer solid content concentration of 3.5%, an additive (Add.1) was added at a ratio of 15% by weight relative to the weight of the polymer, and the additive (Add .2) It is added in a proportion of 10% by weight based on the weight of the polymer. The obtained polyamic acid solution was used as PD-2.

[Synthesis Example PD-3 and Synthesis Example PD-4]

The poly (amino acid) solution (PC-29) and poly (amino acid) solution (PC-31) having a polymer solid content concentration of 3.5% by weight were added with the additive (Add.1) to 15 based on the weight of the polymer. It is added in a proportion of% by weight, and the additive (Add. 2) is added in a proportion of 10% by weight relative to the weight of the polymer. The obtained polyamic acid solution was used as PD-3 and PD-4. The composition ratios of the polyamic acid solution, the additive, and the solvent are shown in Table 4 together with PD-1 and PD-2.

[Example 1]

<Evaluation of inkjet ejectability>

As a liquid crystal alignment agent, a polyamic acid solution (PC-1) having a polymer solid content concentration of 4% by weight was prepared by blending, and an inkjet device DMP- manufactured by FUJIFILM Dimatix was used. 2831, a 60-minute continuous ejection experiment was performed. Five nozzles (nozzle 1) were confirmed with a monitor, and clogging of the nozzles could not be confirmed during continuous ejection for 60 minutes (see ink droplet 2 and mirror reflection image 3 in FIG. 1).

<In-plane streak unevenness and edge linearity in inkjet printing>

Furthermore, this liquid crystal alignment agent was applied on a glass substrate with ITO using an inkjet device EB100XY100 manufactured by Konica Minolta. After coating, it was left for 180 seconds, and dried on a hot plate at 60 ° C for 80 seconds. Then, apply Observation of the substrate. The in-plane streak unevenness was judged by visual confirmation, and the straightness of the edge was judged by measuring the unevenness of the edge by observing with a microscope. As a result, unevenness of the in-plane streaks was not observed and was uniform. Furthermore, as a result of microscopic observation, the unevenness of the edges was 0.2 mm or less, and the linearity was good (see FIG. 3).

[Example 2 to Example 28, Comparative Example 1 to Comparative Example 8]

Except that the polyamic acid solution shown in Tables 3 and 4 was used as the liquid crystal alignment agent, the method according to Example 1 was used to evaluate ejection properties, unevenness of in-plane streaks, and linearity of edges. The results are shown in Table 5 together with Example 1.

As shown in Table 5, it was confirmed that the liquid crystal alignment agent containing a solvent containing four groups was printed by an inkjet method, and it was confirmed that ejection properties, unevenness of in-plane streaks, and straightness of edges were improved.

[Example 29, Example 30 and Reference Example 1, Reference Example 2]

<Presence or absence of flow alignment at the time of cell injection, evaluation of contrast, and AC afterimage>

[Example 29]

A polyamic acid solution (PC-1) having a polymer solid content concentration of 4% by weight as a liquid crystal alignment agent was used as a liquid crystal alignment agent, and the liquid crystal alignment agent was applied to a SiNx / ITO comb-shaped electrode using a spinner. On the substrate, on the opposite side, an inkjet coating device (inkjet device EB100XY100 manufactured by Konica Minolta) was used to coat a glass substrate with a spacer (the height of the spacer: 4 μm). on. In addition, the liquid crystal alignment film was adjusted to have the following film thickness by adjusting the droplet interval and applying a voltage to a cartridge. After coating, it was heated and dried at 70 ° C. for 80 seconds on a hot plate (manufactured by AS ONE Co., Ltd., EC hot plate (EC-1200N)). Next, a multi-light ML-501C / B manufactured by Ushio Motor Co., Ltd. was used to irradiate the linearly polarized light with ultraviolet rays through a polarizing plate through a polarizer in the vertical direction of the substrate. The exposure energy at this time was measured using a UV cumulative light meter UIT-150 (receiver UVD-S365) manufactured by Ushio Motor Co., Ltd. to measure the light amount to 1.0 ± 0.1 J / cm ² at a wavelength of 365 nm. Adjust the exposure time. Then, in a clean oven (Espec Co., Ltd., PVHC-231), heat treatment was performed at 230 ° C. for 15 minutes to form a liquid crystal alignment film with a film thickness of 100 ± 10 nm.

<Production of FFS unit, confirmation of flow alignment, measurement of contrast and AC afterimage>

The two substrates on which the liquid crystal alignment film is formed face each other with the alignment film formed thereon so that the polarization directions of the ultraviolet rays irradiated to the liquid crystal alignment films become parallel, and further formed between the opposite alignment films. It is used for injecting and bonding the voids of the positive type liquid crystal composition, and assembling an empty FFS cell with a cell thickness of 4 μm. The positive-type liquid crystal composition A was vacuum-injected into the produced empty FFS cell to produce an FFS liquid crystal display element. The alignment of the liquid crystal in the obtained liquid crystal display element was confirmed, and as a result, no flow alignment was observed. As a result of measuring the contrast value, it was 3080, and as a result of the AC afterimage measurement, ΔB was 1.8%.

Positive liquid crystal composition A

[Reference Example 1]

A polyamic acid solution (PC-1) having a polymer solid content concentration of 4% by weight as a liquid crystal alignment agent was applied to the substrate with a SiNx / ITO comb-shaped electrode by a spinner, and The opposite side was coated on a glass substrate (spacer height: 4 μm) with a spacer using a spinner (Mikasa Co., Ltd., spin coater (1H-DX2)). In addition, including the following examples and comparative examples, the rotation speed of the spinner was adjusted according to the viscosity of the liquid crystal alignment agent, so that the alignment film had the following film thickness. After coating, it was heated and dried at 70 ° C. for 80 seconds on a hot plate (manufactured by AS ONE Co., Ltd., EC hot plate (EC-1200N)). Next, a multi-light ML-501C / B manufactured by Ushio Motor Co., Ltd. was used to irradiate the linearly polarized light with ultraviolet rays through a polarizing plate through a polarizer in the vertical direction of the substrate. The exposure energy at this time was measured using a UV cumulative light meter UIT-150 (receiver UVD-S365) manufactured by Ushio Motor Co., Ltd. to measure the light amount to 1.0 ± 0.1 J / cm ² at a wavelength of 365 nm. Adjust the exposure time. Then, in a clean oven (Espec Co., Ltd., PVHC-231), heat treatment was performed at 230 ° C. for 15 minutes to form an alignment film having a film thickness of 100 ± 10 nm.

<Production of FFS unit, confirmation of flow alignment, measurement of contrast and AC afterimage>

The orientations of the two substrates on which the alignment films are formed on the substrates are aligned so that the polarization directions of the ultraviolet rays irradiated to the respective alignment films become parallel, and further between the opposite alignment films are formed. The voids of the positive-type liquid crystal composition were injected and bonded, and an empty FFS cell having a cell thickness of 4 μm was assembled. The following positive-type liquid crystal composition A was vacuum-injected into the produced empty FFS cell to produce an FFS liquid crystal display element. The alignment of the liquid crystal in the obtained liquid crystal display element was confirmed, and as a result, no flow alignment was observed. The result of measuring the contrast value was 3050, and the result of measuring the AC afterimage was ΔB of 1.9%.

[Example 30]

A polyamic acid solution (PD-1) having a polymer solid content concentration of 4% by weight as a liquid crystal alignment agent was used as a liquid crystal alignment agent, and the liquid crystal alignment agent was coated on a SiNx / ITO comb-shaped electrode by a spinner. The substrate on the opposite side was coated on a glass substrate with a spacer (the height of the spacer: 4 μm) by using an inkjet coating device (the inkjet device EB100XY100 manufactured by Konica Minolta) on the opposite side. )on. In addition, the droplet interval and the voltage applied to the ink cartridge were adjusted so that the liquid crystal alignment film had the following film thickness. After coating, it was heated and dried at 70 ° C. for 80 seconds on a hot plate (manufactured by AS ONE Co., Ltd., EC hot plate (EC-1200N)). Next, a multi-light ML-501C / B manufactured by Ushio Motor Co., Ltd. was used to irradiate the linearly polarized light with ultraviolet rays through a polarizing plate through a polarizer in the vertical direction of the substrate. The exposure energy at this time was measured using a UV cumulative light meter UIT-150 (receiver UVD-S365) manufactured by Ushio Motor Co., Ltd. to measure the light amount to 1.0 ± 0.1 J / cm ² at a wavelength of 365 nm. Adjust the exposure time. Then, in a clean oven (Espec Co., Ltd., PVHC-231), heat treatment was performed at 230 ° C. for 15 minutes to form a liquid crystal alignment film having a film thickness of 100 ± 10 nm.

<Production of FFS unit, confirmation of flow alignment, measurement of contrast and AC afterimage>

The two substrates on which the liquid crystal alignment film is formed face each other with the alignment film formed thereon so that the polarization directions of the ultraviolet rays irradiated to the liquid crystal alignment films become parallel, and further formed between the opposite alignment films. It is used for injecting and bonding the voids of the liquid crystal composition and assembling an empty FFS cell with a cell thickness of 4 μm. The positive-type liquid crystal composition A was vacuum-injected into the produced empty FFS cell to produce an FFS liquid crystal display element. The alignment of the liquid crystal in the obtained liquid crystal display element was confirmed, and as a result, no flow alignment was observed. The result of measuring the contrast value was 3010, and the result of measuring the AC afterimage was ΔB of 2.2%.

[Reference Example 2]

A polyamic acid solution (PD-1) having a polymer solid content concentration of 4% by weight as a liquid crystal alignment agent was applied to the substrate with a SiNx / ITO comb electrode using a spinner, and The opposite side was coated on a glass substrate (spacer height: 4 μm) with a spacer using a spinner (Mikasa Co., Ltd., spin coater (1H-DX2)). In addition, including the following examples and comparative examples, the rotation speed of the spinner was adjusted according to the viscosity of the liquid crystal alignment agent, so that the alignment film had the following film thickness. After coating, it was heated and dried at 70 ° C. for 80 seconds on a hot plate (manufactured by AS ONE Co., Ltd., EC hot plate (EC-1200N)). Next, a multi-light ML-501C / B manufactured by Ushio Motor Co., Ltd. was used to irradiate the linearly polarized light with ultraviolet rays through a polarizing plate through a polarizer in the vertical direction of the substrate. The exposure energy at this time was measured using a UV cumulative light meter UIT-150 (receiver UVD-S365) manufactured by Ushio Motor Co., Ltd. to measure the light amount to 1.0 ± 0.1 J / cm ² at a wavelength of 365 nm. Adjust the exposure time. Then, in a clean oven (Espec Co., Ltd., PVHC-231), heat treatment was performed at 230 ° C. for 15 minutes to form an alignment film having a film thickness of 100 ± 10 nm.

<Production of FFS unit, confirmation of flow alignment, measurement of contrast and AC afterimage>

The orientations of the two substrates on which the alignment films are formed on the substrates are aligned so that the polarization directions of the ultraviolet rays irradiated to the respective alignment films become parallel, and further between the opposite alignment films are formed. The voids of the positive-type liquid crystal composition were injected and bonded, and an empty FFS cell having a cell thickness of 4 μm was assembled. The positive-type liquid crystal composition A was vacuum-injected into the produced empty FFS cell to produce an FFS liquid crystal display element. The alignment of the liquid crystal in the obtained liquid crystal display element was confirmed, and as a result, no flow alignment was observed. The result of measuring the contrast value was 3000, and the result of measuring the AC afterimage was ΔB of 2.3%.

As described above, the following two types of FFS liquid crystal display elements are compared in terms of presence or absence of flow alignment, contrast, and AC afterimage. The FFS liquid crystal display elements are: the liquid crystal alignment agent of the present invention is printed on the inkjet method on An FFS liquid crystal display element having a liquid crystal alignment film formed by drying, ultraviolet irradiation, and heat treatment of a coating film obtained on a substrate; applying the same liquid crystal alignment agent by a spin coating method, and drying the same, An FFS liquid crystal display element having a liquid crystal alignment film formed by ultraviolet irradiation and heat treatment; as a result, a coating film using an inkjet method is compared with a light alignment film obtained using a coating film using a spin coating method. The performance of the obtained photo-alignment film is not inferior, and it shows good cell characteristics.

<Synthesis of Polyamic Acid>

[Synthesis example A-5]

In a 200 mL brown four-necked flask equipped with a thermometer, a stirrer, a raw material input port and a nitrogen inlet port, 1.4209 g of DAAB, 0.6666 g of DDBU, 0.0257 g of APDA, and 54.0 g of dehydrated NMP were added, and the mixture was stirred under a stream of dry nitrogen. Dissolve. Then, 3.8869 g of tetracarboxylic dianhydride of formula (10) was added, and 20.0 g of dehydrated NMP was further added, and stirring was continued at room temperature for 24 hours. 20.0 g of BP was added to the reaction solution to obtain a polyamidic acid solution having a polymer solid content concentration of 6% by weight. This polyamic acid solution was used as PA-5. The weight average molecular weight of the polyamidic acid contained in PA-5 was 11,300.

[Synthesis Example A-6 to Synthesis Example A-10]

Except changing the composition of the tetracarboxylic dianhydride, diamine, and solvent, the polymer solid content concentration of 6% by weight polyamic acid solution (PA-6) to polyamic acid was prepared based on Synthesis Example A-5. Solution (PA-10). Table 6 shows the composition of raw materials and solvents together with PA-5.

[Synthesis example B-7]

In a 200 mL brown four-necked flask equipped with a thermometer, a stirrer, a raw material input port and a nitrogen inlet port, add 1.9123 g of APDA, 0.8561 g of DDE, 0.3082 g of PDA, and 54.0 g of dehydrated NMP, and stir under a dry nitrogen stream. Dissolve. Then, 1.0424 g of the tetracarboxylic dianhydride of the formula (2) and 1.7585 g of the tetracarboxylic dianhydride of the formula (4) were added, 20.0 g of dehydrated NMP was further added, and stirring was continued at room temperature for 24 hours. 20.0 g of BP was added to the reaction solution to obtain a polyamidic acid solution having a polymer solid content concentration of 6% by weight. This polyamic acid solution was used as PB-7. The weight average molecular weight of the polyamidic acid contained in PB-7 was 48,000. Table 7 shows the composition of the raw materials and the solvent.

<Polymer Blend>

[Synthesis example PC-33]

The polymer solid content concentration of the polymer solid content concentration prepared in [A] Synthesis Example A-5 was 6% by weight, and the polymer solid content concentration prepared in [B] Synthesis Example B-7 It is a 6 wt% polyamic acid solution (PB-7), and mixed with [A] / [B] = 3.0 / 7.0 (weight ratio). Furthermore, the mixed solution was diluted with a solution of NMP / BP / GBL / EDM / BDM / DIBK, and a polyamic acid solution having a polymer solid content concentration of 4% by weight was used as PC-33. At this time, the composition ratio (weight ratio) of the solvents used in the dilution was 0.067 g of NMP, 2.667 g of BP, 13.60 g of GBL, 15.00 g of EDM, 1.00 g of BDM, and 1.00 g of DIBK.

[Synthesis example PC-34 to Synthesis example PC-40]

[A] A polyamic acid solution selected from the group consisting of a polyamino acid solution (PA-5) and a polyamino acid solution (PA-10), and [B] containing a polyamino acid solution (PB-7) ) Of the polyamic acid solution was mixed at a weight ratio [A] / [B] = 3.0 / 7.0 (weight ratio), and further, the polymer solid content concentration was shown in Table 8 by weight, and various solvents were used to Diluted to prepare polyamine solution (PC-34) ~ polyamine solution (PC-36). In addition, polyamines (PC-37) to polyamines (PC-40) were selected from polyamines using various solvents so that the polymer solid content concentration became the weight% described in Table 8. (PA-6) ~ Polyamino acid solution (PA-9) is adjusted by diluting it. Table 8 shows the composition ratio of the polyamic acid solution and the solvent together with PC-33.

[Synthesis example PD-5]

The additive (Add. 2) was added to the polyamic acid solution (PC-33) having a polymer solid content concentration of 4% by weight in a proportion of 10% by weight relative to the weight of the polymer. The obtained polyamic acid solution was used as PD-5.

[Synthesis example PD-6 to Synthesis example PD-8]

The poly (amino acid) solution (PC-34) to the poly (amino acid) solution (PC-36) having a polymer solid content concentration of 4.0% by weight was added with the additive (Add.2) to the polymer. It is added at a ratio of 10% by weight based on the weight of the substance. Let the obtained polyamic acid solution be PD-6 ~ PD-8.

[Synthesis Example PD-9 ~ Synthesis Example PD-12]

The poly (amino acid solution) (PC-37) to poly (amino acid solution) (PC-40) with a polymer solid concentration of 4.0% by weight was added with an additive (Add.2) of 5 to the polymer weight. Added by weight. Let the obtained polyamic acid solution be PD-9 ~ PD-12.

The composition ratios of the polyamic acid solution, the additive, and the solvent are shown in Table 9 together with PD-5 to PD-8.

[Example 31]

<Evaluation of inkjet ejectability>

Polybutamine acid with a solid content concentration of 4% by weight of the polymer prepared by blending Liquid (PC-33) was used as a liquid crystal alignment agent, and an inkjet device DMP-2831 manufactured by FUJIFILM Dimatix was used for a continuous ejection experiment for 60 minutes. Five nozzles were confirmed with a monitor, and no clogging of the nozzles could be confirmed during continuous ejection for 60 minutes.

<In-plane streak unevenness and edge linearity in inkjet printing>

Furthermore, this liquid crystal alignment agent was applied on a glass substrate with ITO using an inkjet device EB100XY100 manufactured by Konica Minolta. After coating, it was left for 180 seconds, and dried on a hot plate at 60 ° C for 80 seconds. Then, observation of the coated substrate was performed. The in-plane streak unevenness was judged by visual confirmation, and the straightness of the edge was judged by measuring the unevenness of the edge by observing with a microscope. As a result, unevenness of the in-plane streaks was not observed and was uniform. Furthermore, as a result of microscopic observation, the unevenness of the edge was 0.2 mm or less, and the linearity was good.

[Example 32 to Example 42]

Except that the polyamic acid solution shown in Tables 8 and 9 was used as the liquid crystal alignment agent, the method according to Example 29 was used to evaluate ejection properties, unevenness of in-plane streaks, and linearity of edges. The results are shown in Table 10 together with Example 31.

[Industrial availability]

It has been confirmed that the liquid crystal alignment agent of the present invention can form a liquid crystal alignment film with good ejection properties, uneven in-plane streaks, or linearity at the edges. The liquid crystal alignment agent of the present invention can be suitably applied to a model requiring a narrow frame.

Claims (11)

A liquid crystal alignment agent comprising at least one polymer and a solvent selected from the group consisting of polyamic acid and its derivatives; and the solvent contains a solvent selected from N-methyl-2-pyrrolidone, γ -At least one of the group consisting of butyrolactone, 1,3-dimethyl-2-imidazolidinone, and N-ethyl-2-pyrrolidone as a first solvent, and contains a component selected from the group consisting of butyl cellosolve At least one of the group consisting of 1,1-butoxy-2-propanol, diethylene glycol ethyl methyl ether, and diethylene glycol propyl methyl ether, as a second solvent, containing a group selected from the group consisting of diisobutyl At least one of a group consisting of a methyl ketone and dipentyl ether is used as a third solvent, and at least one of the groups selected from a compound represented by the following formula (1) is used as a fourth solvent, The proportion of the polymer relative to the total amount of the polymer and the solvent is 0.1% to 40% by weight; In formula (1), when R ¹ is an alkyl group having ² carbon atoms, R ² is an alkyl group having 3 carbon atoms, and when R ¹ is an alkyl group having 4 carbon atoms, R ² is an alkyl group having 1 or 2 carbon atoms. base. The liquid crystal alignment agent according to item 1 of the scope of patent application, wherein the proportion of the first solvent is 20% to 89% by weight relative to the weight of the entire solvent, and the proportion of the second solvent is 10% by weight relative to the weight of the entire solvent 60% by weight, the ratio of the third solvent is 0.1% to 15% by weight with respect to the total solvent weight, and the ratio of the fourth solvent is 0.1% to 20% by weight relative to the total solvent weight. The liquid crystal alignment agent according to claim 1 or claim 2, wherein the tetracarboxylic dianhydride used in the synthesis of the polymer contains a compound selected from the following formulae (AN-I) to (AN-VII) At least one of the group of compounds represented by the formula; and the diamine contains a diamine selected from the following formulae (DI-1) to (DI-16) without a side chain, and the following formula (DIH- 1) In the group consisting of dihydrazine without a side chain represented by formula (DIH-3) and a diamine with a side chain represented by the following formula (DI-31) to (DI-35) At least one In formula (AN-I), formula (AN-IV) and formula (AN-V), X is independently a single bond or -CH _2- ; in formula (AN-II), G is a single bond and carbon number 1 ~ 20 alkylene, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- ; formula (AN-II) ~ formula In (AN-IV), Y is independently one selected from the group of a trivalent group described below, and the bond is linked to an arbitrary carbon. At least one hydrogen of the group may be methyl, ethyl Group or phenyl group; In formulas (AN-III) to (AN-V), ring A ¹⁰ is a group of a monocyclic hydrocarbon having 3 to 10 carbons or a group of a condensing polycyclic hydrocarbon having 6 to 30 carbons. At least one hydrogen of the group may be substituted by methyl, ethyl, or phenyl, and the bonding bond hanging on the ring is linked to any carbon constituting the ring, and two bonding bonds may also be linked to the same carbon; the formula (AN -VI), X ¹⁰ is an alkylene group having 2 to 6 carbon atoms, Me represents a methyl group, and Ph represents a phenyl group; in the formula (AN-VII), G ^{10 is} independently -O-, -COO-, or- OCO-, r is independently 0 or 1; In the formula (DI-1), G ²⁰ is -CH _2- , at least one -CH ₂ -may be substituted with -NH-, -O-, m is an integer from 1 to 12, and at least one of alkylene Hydrogen may be substituted with -OH; in formula (DI-3) and formula (DI-5) to formula (DI-7), G ^{21 is} independently a single bond, -NH-, -NCH _3- , -O-, -S-, -SS-, -SO _2- , -CO-, -COO-, -CONCH _3- , -CONH-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -,-( CH ₂ ) _m- , -O- (CH ₂ ) _m -O-, -N (-Ra)-(CH ₂ ) _k -N (-Ra)-,-(OC ₂ H ₄ ) _m -O-, -O-CH ₂ -C (CF ₃ ) ₂ -CH ₂ -O-, -O-CO- (CH ₂ ) _m -CO-O-, -CO-O- (CH ₂ ) _m -O-CO- ,-(CH ₂ ) _m -NH- (CH ₂ ) _m- , -CO- (CH ₂ ) _k -NH- (CH ₂ ) _k -,-(NH- (CH ₂ ) _m ) _k -NH-, -CO-C ₃ H _6- (NH-C ₃ H ₆ ) _n -CO- or -S- (CH ₂ ) _m -S-, Ra is an alkyl group having 1 to 3 carbon atoms, and m is independently 1 to An integer of 12, k is an integer of 1 to 5, and n is 1 or 2; in formula (DI-4), s is independently an integer of 0 to 2; G ^{22 is} independently a single bond, -O-, -S-, -CO-, -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -NH-, or a carbon number of 1 to 10 Alkylene; at least one hydrogen of cyclohexane ring and benzene ring in formula (DI-2) to formula (DI-7) can pass through -F, -Cl, alkane having 1 to 3 carbon atoms _{, -OCH 3, -OH, -CF 3} , -CO 2 H, -CONH 2, -NHC 6 H 5, substituted phenyl or benzyl group, except, of formula (DI-4), the benzene ring At least one hydrogen may be substituted with one selected from the group consisting of a group represented by the following formulae (DI-4-a) to (DI-4-e); the bonding position in the formula is A group that is not fixed on a carbon atom constituting a ring indicates that the bonding position in the ring is arbitrary; the bonding position of -NH ₂ on a cyclohexane ring or a benzene ring is a bond other than G ²¹ or G ²² Any position other than the position; In formula (DI-4-a) and formula (DI-4-b), R ^{20 is} independently hydrogen or -CH ₃ ; In formula (DI-11), r is 0 or 1; in formulas (DI-8) to (DI-11), the bonding position of -NH ₂ bonded to the ring is an arbitrary position; In the formula (DI-12), R ²¹ and R ^{22 are} independently an alkyl group or a phenyl group having 1 to 3 carbon atoms, and G ^{23 is} independently an alkylene group, a phenylene group, or an alkyl group having 1 to 6 carbon atoms. Substituted phenyl group, w is an integer from 1 to 10; in formula (DI-13), R ^{23 is} independently an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms or -Cl, p Independently an integer of 0 to 3, q is an integer of 0 to 4; in formula (DI-14), ring B is a monocyclic heterocyclic aromatic group, and R ²⁴ is hydrogen, -F, -Cl, carbon 1 to 6 alkyl, alkoxy, vinyl, alkynyl, q is independently an integer of 0 to 4; in formula (DI-15), ring C is a heterocyclic aromatic group or heterocyclic aliphatic Group group; in the formula (DI-16), G ²⁴ is a single bond, an alkylene group having 2 to 6 carbon atoms or 1,4-phenylene group, and r is 0 or 1; A group that is not fixed on a carbon atom constituting a ring indicates that its bonding position in the ring is arbitrary; in formulas (DI-13) to (DI-16), a bond of -NH ₂ on the ring The knot position is arbitrary; In formula (DIH-1), G ²⁵ is a single bond, an alkylene group having 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- ; In the formula (DIH-2), the ring D is a cyclohexane ring, a benzene ring or a naphthalene ring, and at least one hydrogen of the group may be substituted by a methyl group, an ethyl group or a phenyl group ; In formula (DIH-3), the ring E is independently a cyclohexane ring or a benzene ring, at least one hydrogen of the group may be substituted by a methyl group, an ethyl group or a phenyl group, and Y is a single bond and a carbon number. 1 to 20 alkylene, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- ; formula (DIH-2) and In formula (DIH-3), the bonding position of -CONHNH ₂ bonded to the ring is an arbitrary position; In formula (DI-31), G ²⁶ is a single bond, -O-, -COO-, -OCO-, -CO-, -CONH-, -CH ₂ O-, -OCH _2- , -CF ₂ O- , -OCF ₂ -or-(CH ₂ ) _{m '} -, m' is an integer from 1 to 12; R ²⁵ is an alkyl group having 3 to 30 carbon atoms, a phenyl group, a group having a steroid skeleton, or the following formula A group represented by (DI-31-a). In the alkyl group, at least one hydrogen may be substituted by -F, and at least one -CH ₂ -may be substituted by -O-, -CH = CH-, or -C≡. Substituted by C-, the hydrogen of the phenyl group may be -F, -CH ₃ , -OCH ₃ , -OCH ₂ F, -OCHF ₂ , -OCF ₃ , alkyl group having 3 to 30 carbon atoms, or 3 to 30 carbon atoms. Substituted by alkoxy, the bonding position of -NH ₂ bonded to the benzene ring is indicated at any position in the ring, In the formula (DI-31-a), G ²⁷ , G ²⁸ and G ²⁹ are bonding groups, and these groups are independently a single bond or an alkylene group having 1 to 12 carbon atoms. The above -CH ₂ -may be replaced by -O-, -COO-, -OCO-, -CONH-, -CH = CH-, and ring B ²¹ , ring B ²² , ring B ²³ and ring B ^{24 are} independently 1,4-phenylene, 1,4-cyclohexyl, 1,3-dioxane-2,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl, naphthalene At least one hydrogen of -1,5-diyl, naphthalene-2,7-diyl or anthracene-9,10-diyl, ring B ²¹ , ring B ²² , ring B ²³ and ring B ²⁴ may pass through -F Or -CH ₃ , and s, t, and u are independently integers of 0 to 2. The total of these is 1 to 5. When s, t, or u is 2, the two bonding groups in each bracket can be The same or different, and the two rings may be the same or different. R ²⁶ is hydrogen, -F, -OH, alkyl having 1 to 30 carbons, fluorine substituted alkyl having 1 to 30 carbons, carbon An alkoxy group having 1 to 30, -CN, -OCH ₂ F, -OCHF ₂ , or -OCF _3. At least one of the alkyl groups having 1 to 30 carbon atoms -CH ₂ -can be obtained by the following formula (DI- 31-b) is substituted by a divalent group represented by In formula (DI-31-b), R ²⁷ and R ^{28 are} independently an alkyl group having 1 to 3 carbon atoms, and v is an integer of 1 to 6; In formula (DI-32) and formula (DI-33), G ^{30 is} independently a single bond, -CO- or -CH _2- , R ^{29 is} independently hydrogen or -CH ₃ , and R ³⁰ is hydrogen and carbon number 1 to 20 alkyl groups, or alkenyl groups having 2 to 20 carbon atoms; at least one hydrogen of the benzene ring in formula (DI-33) may be substituted with 1 to 20 carbon groups or phenyl groups; the formula A group in which the bonding position in is not fixed to any carbon atom constituting the ring indicates that the bonding position in the ring is arbitrary; in formulas (DI-32) and (DI-33), the bond is -NH ₂ on the benzene ring means that its bonding position in the ring is arbitrary; In formula (DI-34) and formula (DI-35), G ^{31 is} independently -O- or an alkylene group having 1 to 6 carbon atoms, G ³² is a single bond or an alkylene group having 1 to 3 carbon atoms, R ³¹ is hydrogen or an alkyl group having 1 to 20 carbon atoms. At least one -CH ₂ -of the alkyl group may be substituted by -O-, -CH = CH-, or -C≡C-, and R ³² is 6 carbon atoms. ~ 22 alkyl group, R ³³ is hydrogen or alkyl group having 1 to 22 carbon atoms, ring B ²⁵ is 1,4-phenylene or 1,4-cyclohexyl, r is 0 or 1, and -NH ₂ on the benzene ring indicates that the bonding position in the ring is arbitrary. The liquid crystal alignment agent according to claim 1 or claim 2, wherein the tetracarboxylic dianhydride used in the synthesis of the polymer contains a compound selected from the compounds represented by the following formulae (2) to (13). At least one of a group; and the diamine contains at least one selected from the group of a compound represented by the following formula (D-1) to formula (D-5); At least one of the hydrogens in the formula may be substituted with -CH ₃ , -CH ₂ CH ₃ or phenyl; In formula (D-2) and formula (D-4), X and Y are independently a single bond, -O-, -NH-, -S- or an alkylene group having 1 to 6 carbon atoms; formula (D- In 4), a is an integer of 1 to 8; in the formula (D-5), Ra is an alkyl group having 1 to 3 carbons; and at least one hydrogen of the benzene ring may be substituted by -CH ₃ . The liquid crystal alignment agent according to item 1 or item 2 of the scope of patent application, wherein the polyamino acid and its derivative are raw material monomers that make at least one of tetracarboxylic dianhydride and diamine have a photoreactive structure. Polymer (a) obtained by reaction. The liquid crystal alignment agent according to item 5 of the patent application, wherein the diamine includes 4,4'-diaminoazobenzene. The liquid crystal alignment agent according to item 5 of the scope of patent application, which includes not only the polymer (a), but also a tetracarboxylic dianhydride selected from the group consisting of tetracarboxylic dianhydride having no photoreactive structure and At least one polymer (b) of polyamidic acid and a derivative thereof obtained by an amine reaction. The liquid crystal alignment agent according to item 5 of the scope of patent application, wherein the tetracarboxylic dianhydride used in the synthesis of the polymer (b) contains a group selected from the compounds represented by the following formulae (2) to (13) At least one of a group; and the diamine contains at least one selected from the group of compounds represented by the following formulae (D-1) to (D-5); At least one of the hydrogens in the formula may be substituted with -CH ₃ , -CH ₂ CH ₃ or phenyl; In formula (D-2) and formula (D-4), X and Y are independently a single bond, -O-, -NH-, -S-, or an alkylene group having 1 to 6 carbon atoms; formula (D In -4), a is an integer of 1 to 8; in formula (D-5), Ra is an alkyl group having 1 to 3 carbons; and at least one hydrogen of a benzene ring in the formula may be passed through -CH ₃ Was replaced. The liquid crystal alignment agent according to item 5 of the patent application scope, further comprising at least one selected from the group consisting of an oxazine compound, an oxazoline compound, an epoxy compound, and a compound containing a silane coupling agent. A liquid crystal alignment film is formed by using the liquid crystal alignment agent according to any one of claims 1 to 9 of a patent application scope. A liquid crystal display element includes the liquid crystal alignment film according to item 10 of the patent application scope.