TWI644947B - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Abstract

The invention provides a liquid that can produce excellent light stability and brightness stability. A liquid crystal alignment agent for a crystal display element, a liquid crystal alignment film, and a liquid crystal display element having the liquid crystal alignment film. The liquid crystal alignment agent includes a photo-alignable polysiloxane (A) and a solvent (B), wherein the photo-alignable polysiloxane (A) is a polysiloxane (a-1) containing an acid anhydride group. It is obtained by reacting with an epoxy-containing cinnamic acid derivative (a-2).

Description

Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element

The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film and a liquid crystal display element, and more particularly, to a liquid crystal alignment agent capable of producing a liquid crystal alignment film with excellent light stability and brightness stability, and a liquid crystal having the same Display element.

Liquid crystal displays are widely used in televisions and various monitors. As the LCD display element, an LCD display element having the following liquid crystal cells is known: Twisted Nematic (TN) type, Super Twisted Nematic (STN) type, In Plane Switching , IPS) type, Fringe Field Switching (FFS) type that changes the electrode structure such as IPS type, and increases the aperture ratio of the display element part to increase the brightness.

As a method for aligning the liquid crystal of these liquid crystal cells, the following method is known: forming an organic film such as a liquid crystal alignment film on the substrate surface, and rubbing the organic film with a cloth material such as rayon in a certain direction Surface; on the substrate table Oblique vapor deposition of silicon oxide; methods such as forming a monomolecular film having a long-chain alkyl group using the LB method (Langmuir-Blodgett). Among these, from the viewpoints of substrate size, liquid crystal alignment uniformity, processing time, and processing cost, the most common is the use of friction processing.

However, if the alignment of the liquid crystal is performed by a rubbing treatment, it is feared that dust or static electricity generated during the process may cause dust to adhere to the surface of the alignment film and cause display failure. In particular, for a substrate having a thin film transistor (TFT) element, static electricity generated may cause the circuit of the TFT element to be damaged, resulting in a decrease in yield. Furthermore, as liquid crystal display elements that are gradually becoming more refined in the future, unevenness is generated on the substrate surface as the pixel density becomes higher, so that it is difficult to uniformly perform rubbing treatment.

Therefore, in order to avoid the occurrence of the above-mentioned undesirable state, a photo-alignment method that imparts liquid crystal alignment ability by irradiating a photosensitive film with polarized or unpolarized radiation (for example, Japanese Patent Laid-Open No. 2005-037654) is known. The document proposes a liquid crystal alignment agent having a conjugated enone repeating unit and a fluorene imine structure. As a result, static electricity and dust will not be generated, and uniform liquid crystal alignment can be achieved. In addition, compared with the rubbing process, this method can precisely control the liquid crystal alignment direction in any direction. Furthermore, by using a photomask or the like when radiating radiation, a plurality of regions having different liquid crystal alignment directions can be arbitrarily formed on one substrate.

However, the liquid crystal display manufactured by the above-mentioned liquid crystal alignment agent for light alignment has unacceptable light stability and brightness stability.

In view of this, the present invention provides a liquid crystal alignment agent, which can produce a liquid crystal alignment film with excellent light stability and brightness stability, and a liquid crystal display element having the alignment film.

The invention provides a liquid crystal alignment agent comprising a photo-alignable polysiloxane (A) and a solvent (B). The photo-alignable polysiloxane (A) is obtained by reacting a polysiloxane (a-1) containing an acid anhydride group and a cinnamic acid derivative (a-2) containing an epoxy group.

In an embodiment of the present invention, the polysiloxane (a-1) containing an acid anhydride group includes a copolymer obtained by hydrolyzing and partially condensing a first mixture, and the first mixture includes Silane monomer (a-1-1) represented by formula (1-1); Si (R ^a ) _w (OR ^b ) _4-w formula (1-1)

In the formula (1-1), R ^a each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 15 carbon atoms, Alkyl, at least one R ^a is an alkyl group containing an acid anhydride group; when R ^a is plural, they may be the same or different; R ^b each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbons, and A fluorenyl group of 1 to 6 or an aryl group having 6 to 15 carbons; when R ^b is plural, each may be the same or different; w represents an integer of 1 to 3;

In an embodiment of the present invention, the epoxy group-containing cinnamic acid derivative (a-2) is a group consisting of compounds represented by formulas (2-1) to (2-2). At least one,

In the formula (2-1), W ¹ represents an alkyl group having 1 to 40 carbon atoms or a monovalent alicyclic organic group having 3 to 40 carbon atoms, wherein a part or all of the hydrogen atoms of the alkyl group May be substituted by a fluorine atom; W ² represents a single bond, an oxygen atom, -COO- or -OCO-; W ³ represents a divalent aromatic group, a divalent alicyclic group; W ⁴ represents a single bond, an oxygen atom, -COO- or -OCO-; W ⁵ represents a single bond,-(CH ₂ ) _h -COO-,-(CH ₂ ) _i -O- or a divalent aromatic group, said divalent aromatic group, It may have -COO- substitution, wherein h and i each independently represent an integer of 1 to 10; W ⁶ represents an epoxy group; W ⁷ represents a fluorine atom or a cyano group; a represents an integer of 0 to 3; b represents 0 to 4 An integer of 0; a + b ≦ 5; t represents an integer of 0 to 1; in formula (2-2), W ⁸ represents an alkyl group having 1 to 40 carbon atoms or a monovalent lipid having 3 to 40 carbon atoms A cyclic organic group in which a part or all of the hydrogen atoms of the alkyl group may be substituted with a fluorine atom; W ⁹ represents an oxygen atom or a divalent aromatic group; W ¹⁰ represents an oxygen atom, -COO- or -OCO- ; W ¹¹ represents a divalent aromatic group and a divalent alicyclic group; W ¹² represents an oxygen atom, -COO-, -OCO -(CH ₂ ) _e -COO- or -OCO- (CH ₂ ) _g -O-, wherein e and g each independently represent an integer of 1 to 10; W ¹³ represents an epoxy group; W ¹⁴ represents a fluorine atom or cyanide Base; c represents an integer from 0 to 3; d represents an integer from 0 to 4; 0 ≦ c + d ≦ 5.

In an embodiment of the present invention, based on the total amount of the silane monomers in the first mixture being 1 mole, the amount of the silane monomer (a-1-1) used is 0.3 to 1.0 mole. ear.

In one embodiment of the present invention, the photo-alignable polysiloxane (A) is used in an amount of 100 parts by weight, and the solvent (B) is used in an amount of 800 to 4,000 parts by weight.

In an embodiment of the invention, the liquid crystal alignment agent further includes a polymer composition (C).

In an embodiment of the present invention, the polymerization composition (C) is obtained by reacting a second mixture, and the second mixture includes a tetracarboxylic dianhydride component (c-1) and a diamine component ( c-2).

In an embodiment of the present invention, the total usage amount of the photo-alignable polysiloxane (A) and the polymer composition (C) is 100 parts by weight, and the use amount of the polymer composition (C) is 1 weight. Parts to 99 parts by weight.

In one embodiment of the present invention, the total usage amount of the photo-alignable polysiloxane (A) and the polymer composition (C) is 100 parts by weight, and the usage amount of the solvent (B) is 800 parts by weight to 4000 parts by weight.

The invention further provides a liquid crystal alignment film, which is formed by the liquid crystal alignment agent described above.

The present invention further provides a liquid crystal display element including the above-mentioned liquid crystal display device. 向 膜。 To the film.

Based on the above, the liquid crystal alignment agent of the present invention can produce a liquid crystal alignment film with excellent light stability and excellent brightness stability, and is suitable for a liquid crystal display element.

In order to make the above features and advantages of the present invention more comprehensible, embodiments are hereinafter described in detail with reference to the accompanying drawings.

100‧‧‧LCD display element

110‧‧‧ Unit 1

112‧‧‧First substrate

114‧‧‧The first conductive film

116‧‧‧The first liquid crystal alignment film

120‧‧‧ Unit 2

122‧‧‧Second substrate

124‧‧‧Second conductive film

126‧‧‧Second LCD alignment film

130‧‧‧LCD unit

FIG. 1 is a side view of a liquid crystal display element according to an embodiment of the present invention.

<Liquid crystal alignment agent>

The invention provides a liquid crystal alignment agent, which includes a photo-alignable polysiloxane (A) and a solvent (B). In addition, if necessary, the liquid crystal alignment agent may further include a polymer composition (C) and an additive (D).

Hereinafter, each component of the liquid crystal alignment agent used in the present invention will be described in detail.

Here, it is explained that acrylic acid and / or methacrylic acid are represented by (meth) acrylic acid, and acrylate and / or methacrylic acid ester are represented by (meth) acrylic acid ester; similarly, (meth) Acrylofluorenyl refers to acrylfluorenyl and / or methacrylfluorenyl.

Photo-alignment polysiloxane (A)

The photo-alignable polysiloxane (A) is a polysiloxane (a-1) containing an acid anhydride group. It is obtained by reacting with an epoxy-containing cinnamic acid derivative (a-2). Specific examples of the polysiloxane (a-1) containing an acid anhydride group and a cinnamic acid derivative (a-2) containing an epoxy group and a synthesis method will be described below.

Polysiloxane (a-1) containing acid anhydride group

The type of the polysiloxane (a-1) containing an acid anhydride group is not particularly limited, but it can achieve the purpose claimed in the present invention. The polysiloxane (a-1) containing an acid anhydride group is obtained by polycondensation (ie, hydrolysis and partial condensation) of a first mixture (ie, a silane monomer component), wherein the first mixture includes Silane monomer (a-1-1). In addition, the silane monomer component may further include, but is not limited to, a silane monomer (a-1-2) other than the silane monomer (a-1-1). Hereinafter, each component of the silane monomer component and the reaction steps and conditions of polycondensation will be further described.

Silane monomer (a-1-1)

The silane monomer (a-1-1) is a compound represented by the formula (1-1).

Si (R ^a ) _w (OR ^b ) _4-w Formula (1-1)

In the formula (1-1), R ^a each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 15 carbon atoms, Alkyl, at least one R ^a is an alkyl group containing an acid anhydride group; when R ^a is plural, each may be the same or different; R ^b each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and the carbon number is A fluorenyl group of 1 to 6 or an aryl group having 6 to 15 carbons; when R ^b is plural, each may be the same or different; w represents an integer of 1 to 3;

More specifically, when R ^a in the formula (1-1) represents an alkyl group having 1 to 10 carbon atoms, specifically, R ^a is, for example, methyl, ethyl, n-propyl, isopropyl, N-butyl, third butyl, n-hexyl or n-decyl. R ^a may be an alkyl group having another substituent on the alkyl group. Specifically, R ^{a is,} for example, trifluoromethyl, 3,3,3-trifluoropropyl, 3-aminopropyl, 3- Thiopropyl or 3-isocyanatopropyl.

When R ^a in the formula (1-1) represents an alkenyl group having 2 to 10 carbon atoms, specifically, R ^{a is,} for example, a vinyl group. R ^a may be an alkenyl group having another substituent on the alkenyl group. Specifically, R ^{a is,} for example, 3-propenyloxypropyl group or 3-methacryloxypropyl group.

When R ^a in the formula (1-1) represents an aryl group having 6 to 15 carbon atoms, specifically, R ^a is, for example, a phenyl group, a tolyl group, or a naphthyl group. R ^a may be an aryl group having another substituent on the aryl group. Specifically, R ^a is, for example, p-hydroxyphenyl, 1- (p-hydroxyphenyl) ethyl (1 -(o-hydroxyphenyl) ethyl), 2- (p-hydroxyphenyl) ethyl (2- (o-hydroxyphenyl) ethyl) or 4-hydroxy-5- (p-hydroxyphenylcarbonyloxy) pentyl ( 4-hydroxy-5- (p-hydroxyphenylcarbonyloxy) pentyl).

In addition, R ^a in the formula (1-1) represents an alkyl group containing an acid anhydride group, and among these, the alkyl group is preferably an alkyl group having 1 to 10 carbon atoms. Specifically, the acid-anhydride-containing alkyl group is, for example, ethylsuccinic anhydride represented by formula (I-1-1), propylsuccinic anhydride represented by formula (I-1-2), or formula ( I-1-3) shown by propylglutaric anhydride. It is worth mentioning that the acid anhydride group is a group formed by dicarboxylic acid by intramolecular dehydration, and the dicarboxylic acid is, for example, succinic acid or glutaric acid.

In addition, when R ^{b of the} formula (1-1) represents an alkyl group having 1 to 6 carbon atoms, specifically, R ^b is, for example, methyl, ethyl, n-propyl, isopropyl, or n-butyl. When R ^b in the formula (1-1) represents a fluorenyl group having 1 to 6 carbon atoms, specifically, R ^{b is,} for example, an ethenyl group. When R ^b in the formula (1-1) represents an aryl group having 6 to 15 carbon atoms, specifically, R ^{b is,} for example, a phenyl group.

In Formula (1-1), w represents an integer of 1 to 3. When w represents 2 or 3, multiple R ^a may be the same or different; when w represents 1 or 2, multiple R ^b may be the same or different.

Specific examples of the silane monomer (a-1-1) include 3- (triphenoxysilyl) propylsuccinic anhydride, and a commercially available product manufactured by Shin-Etsu Chemical: 3- (trimethoxysilyl) propane Succinic anhydride (trade name X-12-967), a commercially available product manufactured by WACKER: 3- (triethoxysilyl) propylsuccinic anhydride (trade name GF-20), 3- ( Trimethoxysilyl) propylglutaric anhydride (TMSG), 3- (triethoxysilyl) propylglutaric anhydride, 3- (triphenoxysilyl) propylglutaric anhydride, (di N-butoxysilyl) bis (propylsuccinic anhydride), (dimethoxysilyl) bis (ethylsuccinic anhydride), (phenoxysilyl) tris (propylsuccinic anhydride), ( Methylmethoxysilyl) bis (ethylsuccinic anhydride), or a combination thereof.

The silane monomer (a-1-1) can be used alone or in combination.

Specific examples of the silane monomer (a-1-1) preferably include 3- (triethoxysilyl) propylsuccinic anhydride, 3- (trimethoxysilyl) propylglutaric anhydride, (di Methoxysilyl) bis (ethylsuccinic anhydride) or a combination thereof.

Based on the total amount of silane monomers in the first mixture being 1 mol, the amount of silane monomer (a-1-1) used is 0.3 mol to 1.0 mol, preferably 0.4 mol to 1.0 mol, And more preferably from 0.5 mol to 1.0 mol.

When the silane monomer (a-1-1) is not included in the first mixture, the light stability of the liquid crystal alignment agent is poor, and the brightness stability is poor.

Based on the total amount of silane monomers in the first mixture being 1 mol, when the silane monomer (a-1-1) is used in an amount of 0.3 to 1.0 mol, the light stability of the liquid crystal display element can be further improved Sex.

Silane monomer (a-1-2)

The silane monomer (a-1-2) is a compound represented by the formula (1-2).

Si (R ^c ) _u (OR ^d ) _4-u Formula (1-2)

In formula (1-2), R ^c each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, and an aryl group having 6 to 15 carbon atoms; when R ^c is When plural, they may be the same or different; each R ^d independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a fluorenyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 15 carbon atoms; when R ^{When d} is a complex number, each may be the same or different; u represents an integer from 0 to 3.

More specifically, when R ^c in the formula (1-2) represents an alkyl group having 1 to 10 carbon atoms, specifically, R ^c is, for example, methyl, ethyl, n-propyl, isopropyl, N-butyl, third butyl, n-hexyl or n-decyl. R ^c may be an alkyl group having another substituent on the alkyl group. Specifically, R ^{c is,} for example, trifluoromethyl, 3,3,3-trifluoropropyl, 3-aminopropyl, 3- Thiopropyl or 3-isocyanatopropyl.

When R ^c in the formula (1-2) represents an alkenyl group having 2 to 10 carbon atoms, specifically, R ^{c is,} for example, a vinyl group. R ^c may be an alkenyl group having another substituent on the alkenyl group. Specifically, R ^{c is,} for example, 3-propenyloxypropyl or 3-methacryloxypropyl.

When R ^c in the formula (1-2) represents an aryl group having 6 to 15 carbon atoms, specifically, R ^c is, for example, a phenyl group, a tolyl group, or a naphthyl group. R ^c may be an aryl group having another substituent on the aryl group. Specifically, R ^c is, for example, p-hydroxyphenyl, 1- (p-hydroxyphenyl) ethyl (1 -(o-hydroxyphenyl) ethyl), 2- (p-hydroxyphenyl) ethyl (2- (o-hydroxyphenyl) ethyl) or 4-hydroxy-5- (p-hydroxyphenylcarbonyloxy) pentyl ( 4-hydroxy-5- (p-hydroxyphenylcarbonyloxy) pentyl).

In addition, when ^{Rd in} Formula (1-2) represents an alkyl group having 1 to 6 carbon atoms, specifically, ^Rd is methyl, ethyl, n-propyl, isopropyl, or n-butyl, for example. When R ^d in the formula (1-2) represents a fluorenyl group having 1 to 6 carbon atoms, specifically, R ^{d is,} for example, an ethenyl group. When ^Rd in the formula (1-2) represents an aryl group having 6 to 15 carbon atoms, specifically, ^{Rd is,} for example, a phenyl group.

In Formula (1-2), u is an integer of 0 to 3. When u represents 2 or 3, multiple R ^c may be the same or different; when u represents 0, 1 or 2, multiple R ^d may be the same or different.

In formula (1-2), when u = 0, it means that the silane monomer is a tetrafunctional silane monomer (that is, a silane monomer having four hydrolyzable groups); when u = 1, it means silane The monomer is a trifunctional silane monomer (that is, a silane monomer having three hydrolyzable groups); when u = 2, it means that the silane monomer is a difunctional silane monomer (that is, two hydrolyzable monomers) Silane monomer); and when u = 3, it means that the silane monomer is a monofunctional silane monomer (that is, a silane monomer having a hydrolyzable group). It is worth mentioning that the hydrolyzable group refers to a group that can undergo a hydrolysis reaction and is bonded to silicon. For example, the hydrolyzable group is, for example, an alkoxy group, an acyloxy group, or a benzene group. Oxy (phenoxy group).

Specific examples of the silane monomer represented by the formula (1-2) include, but are not limited to: (1) tetrafunctional silane monomer: tetramethoxysilane, tetraethoxysilane, tetraethoxysilane Tetraacetoxysilane or tetraphenoxy silane; (2) trifunctional silane monomer: methyltrimethoxysilane (MTMS), methyltriethoxysilane (methyltriethoxysilane) ), Methyltriisopropoxysilane (methyltriisopropoxysilane), methyltri-n-butoxysilane (methyltri-n-butoxysilane), ethyltrimethoxysilane (ethyltrimethoxysilane), ethyltriethoxysilane (ethyltriethoxysilane) , Ethyltriisopropoxysilane, ethyltri-n-butoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane (n-propyltriethoxysilane), n-butyltrimethoxysilane, n-butyltriethoxysilane, n-hexyltrimethoxysilane ), N-hexyltriethoxysilane, decyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, phenyltrimethoxy Silane (phenyltrimethoxysilane (PTMS), phenyltriethoxysilane (PTES), p-hydroxyphenyltrimethoxysilane (p-hydroxyphenyltrimethoxysilane), 1- (p-hydroxyphenyl) ethyltrimethoxysilane ( 1- (p-hydroxyphenyl) ethyltrimethoxysilane), 2- (p-hydroxyphenyl) ethyltrimethoxysilane, 2- (p-hydroxyphenyl) ethyltrimethoxysilane, 4-hydroxy-5- (p-hydroxyphenylcarbonyloxy) ) Pentyltrimethoxysilane (4-hydroxy-5- (p-hydroxyphenylcarbonyloxy) pentyltrimethoxysilane), trifluoromethyltrimethoxysilane, trifluoromethyltriethoxysilane, trifluoromethyltriethoxysilane, 3,3-trifluoropropyltrimethoxysilane (3-, 3-trifluoropropyltrimethoxysilane), 3-aminopropyltrimethoxysilane (3-aminopropyltrimethoxysilane), 3-aminopropyltriethoxysilane (3- aminopropyltriethoxysilane), 3-mercaptopropyltrimethoxysilane, 3-propenyloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, or 3-methacryloxypropylpropane Triethoxysilane; (3) difunctional silane mono : Dimethyldimethoxysilane (DMDMS for short), dimethyldiethoxysilane (dimethyldiethoxysilane), dimethyldiacetyloxysilane (dimethyldiacetyloxysilane), di-n-butyldimethoxysilane ( di-n-butyldimethoxysilane) or diphenyldimethoxysilane; or (4) monofunctional silane monomer: trimethylmethoxysilane (trimethylmethoxysilane) or tri-n-butylethoxysilane (tri-n-butylethoxysilane) and the like. The various silane monomers can be used alone or in combination.

Based on the total amount of silane monomers in the first mixture being 1 mole, the amount of silane monomer (a-1-2) used is 0 to 0.7 mol, preferably 0 to 0.6 mol, more preferably 0 to 0.5 mole.

The first mixture may further include a commercially available silane compound, and specific examples thereof include KC-89, KC-89S, X-21-3153, X-21-5841, X-21-5842, X-21-5843, X-21-5844, X-21-5845, X-21-5846, X-21-5847, X-21-5848, X-22-160AS, X-22-170B, X-22-170BX, X- 22-170D, X-22-170DX, X-22-176B, X-22-176D, X-22-176DX, X-22-176F, X-40-2308, X-40-2651, X-40- 2655A, X-40-2671, X-40-2672, X-40-9220, X-40-9225, X-40-9227, X-40-9246, X-40-9247, X-40-9250, X-40-9323, X-41-1053, X-41-1056, X-41-1805, X-41-1810, KF6001, KF6002, KF6003, KR212, KR-213, KR-217, KR220L, KR242A, KR271, KR282, KR300, KR311, KR401N, KR500, KR510, KR5206, KR5230, KR5235, KR9218, KR9706 (made by Shin-Etsu Chemical); glass resin (GLASS RESIN, manufactured by Showa Denko); SH804, SH805, SH806A, SH840, SR2400, SR2402, SR2405, SR2406, SR2410, SR2411, SR2416, SR2420 (made by Toray Dow Corning); FZ3711, FZ3722 (made by NUC); DMS-S12, DMS-S15, DMS-S21, DMS-S27, DMS-S31, DMS- S32, DMS-S33, DMS-S35, DMS-S38, DMS-S4 2, DMS-S45, DMS-S51, DMS-227, PSD-0332, PDS-1615, PDS-9931, XMS-5025 (made by JNC); MS51, MS56 (made by Mitsubishi Chemical); and GR100, GR650, GR908, GR950 ( Showa Denko) and other condensates.

The polycondensation reaction for forming an epoxy group-containing polysiloxane (a-1) of the present invention can use a general method, for example, adding an organic solvent, water, or optionally further adding it to the above-mentioned silane monomer or a mixture thereof. The catalyst is then heated at 50 ° C to 150 ° C using an oil bath or the like, and the heating time is preferably 0.5 hours to 120 hours. During heating, the mixed solution may be stirred or placed under reflux conditions.

The organic solvent is not particularly limited, and may be the same as or different from the solvent (B) contained in the liquid crystal alignment agent of the present invention. Specific examples of the organic solvent include hydrocarbon compounds such as toluene and xylene; methyl ethyl ketone, methyl isobutyl ketone, methyl n-pentyl ketone, diethyl ketone, cyclohexanone, and 2-butanone , 2-hexanone and other ketone solvents; ethyl acetate, n-butyl acetate, isoamyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, ethyl lactate and other esters Solvents; Ether solvents such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, tetrahydrofuran, dioxane (dioxane); 1-hexanol, 4-methyl 2-pentanol, ethylene glycol mono Methyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, etc. Alcohol solvents; N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, trimethylamine hexamethyl phosphate, 1,3-dimethyl Amidamine-based solvents such as 2-imidazolidinone, or a combination of the above organic solvents.

Based on 1 mole of all silane compounds, the amount of the organic solvent used is preferably from 3 g to 2000 g, more preferably from 6 g to 1500 g.

The hydrolyzable group based on all the silane compounds is 1 mol, and the amount of water used is preferably 0.5 mol to 100 mol, and more preferably 0.5 mol to 30 mol.

The catalyst is not particularly limited. Preferably, the catalyst is selected from the group consisting of an acid, an alkali metal compound, an organic base, a titanium compound, a zirconium compound, or a combination thereof.

Specific examples of the acid include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, trifluoroacetic acid, formic acid, polycarboxylic acid, polybasic acid anhydride, or a combination thereof.

Specific examples of the alkali metal compound include sodium hydroxide, potassium hydroxide, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, or a combination thereof.

Specific examples of the organic base include primary or secondary organic amines such as ethylamine, diethylamine, piperazine, piperidine, pyrrolidine, and pyrrole; triethylamine, triethylamine Tertiary organic amines such as n-propylamine, tri-n-butylamine, pyridine, 4-dimethylaminopyridine, diazabicycloundecene, and other tertiary organic amines such as tetramethylammonium hydroxide Amines, etc. or a combination of the above.

The amount of catalyst used varies depending on the reaction conditions such as type, temperature, etc., and can be appropriately set. For example, based on 1 mol of all silane compounds, the addition amount of the catalyst is 0.01 mol to 5 mol, preferably 0.03 to 3 mol, more preferably 0.05 to 1 mol.

From the viewpoint of stability, after the completion of the polycondensation reaction, the organic solvent layer fractionated from the reaction liquid is preferably washed with water. When performing this washing | cleaning, it is preferable to wash | clean with water containing a small amount of salt, for example, about 0.2 weight% of ammonium nitrate aqueous solution etc. Washing can be performed until the water layer after washing becomes neutral, and then the organic solvent If necessary, the layer is dried with a desiccant such as anhydrous calcium sulfate and molecular sieves, and then the organic solvent is removed to obtain an acid anhydride-containing polysiloxane (a-1).

Epoxy-containing cinnamic acid derivative (a-2)

The epoxy group-containing cinnamic acid derivative (a-2) is at least one of the group consisting of compounds represented by formula (2-1) to formula (2-2).

In the formula (2-1), W ¹ represents an alkyl group having 1 to 40 carbon atoms or a monovalent alicyclic organic group having 3 to 40 carbon atoms, wherein a part or all of the hydrogen atoms of the alkyl group May be substituted by a fluorine atom; W ² represents a single bond, an oxygen atom, -COO- or -OCO-; W ³ represents a divalent aromatic group, a divalent alicyclic group; W ⁴ represents a single bond, an oxygen atom, -COO- or -OCO-; W ⁵ represents a single bond,-(CH ₂ ) _h -COO-,-(CH ₂ ) _i -O- or a divalent aromatic group, said divalent aromatic group, It may have -COO- substitution, wherein h and i each independently represent an integer of 1 to 10; W ⁶ represents an epoxy group; W ⁷ represents a fluorine atom or a cyano group; a represents an integer of 0 to 3; b represents 0 to 4 An integer of 0; 0 ≦ a + b ≦ 5; t represents an integer of 0 to 1.

In the formula (2-2), W ⁸ represents an alkyl group having 1 to 40 carbon atoms or a monovalent alicyclic organic group having 3 to 40 carbon atoms, wherein a part or all of the hydrogen atoms of the alkyl group may be Substituted by a fluorine atom; W ⁹ represents an oxygen atom or a divalent aromatic group; W ¹⁰ represents an oxygen atom, -COO- or -OCO-; W ¹¹ represents a divalent aromatic group, a divalent alicyclic group; W ¹² represents an oxygen atom, -COO-, -OCO- (CH ₂ ) _e -COO- or -OCO- (CH ₂ ) _g -O-, wherein e and g each independently represent an integer of 1 to 10; W ¹³ Represents an epoxy group; W ¹⁴ represents a fluorine atom or a cyano group; c represents an integer of 0 to 3; d represents an integer of 0 to 4; 0 ≦ c + d ≦ 5.

An alkyl group having 1 to 40 carbon atoms in W ¹ in the above formula (2-1), and a preferable example is an alkyl group having 1 to 20 carbon atoms, in which a part or all of the hydrogen atoms of the alkyl group may be fluorine Atomic substitution. Specific examples of the alkyl group include the following: n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-lauryl, n-dodecyl, n-tridecyl , N-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, 4,4,4-tris Fluorobutyl, 4,4,5,5,5-pentafluoropentyl, 4,4,5,5,6,6,6-heptafluorohexyl, 3,3,4,4,5,5,5 -Heptafluoropentyl, 2,2,2-trifluoroethyl, 2,2,3,3,3-pentafluoropropyl, 2- (perfluorobutyl) ethyl, 2- (perfluorooctyl ) Ethyl, 2- (perfluorodecyl) ethyl and the like. Examples of the monovalent alicyclic organic group having a carbon number of 3 to 40 in W ¹ include cholestenyl, cholestanyl, and adamantyl.

Examples of the divalent aromatic group of W ³ and W ⁵ include 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, 2 , 3,5,6-tetrafluoro-1,4-phenylene and the like. Examples of the divalent alicyclic group of W ³ include 1,4-cyclohexylene and the like.

Examples of the epoxy group of W ⁶ and W ¹³ include at least one of a group represented by formula (3-1), a group represented by formula (3-2), and a group represented by formula (3-3). By.

Specifically, the base represented by Formula (3-1) is shown below.

In formula (3-1), B represents an oxygen atom or a single bond; c1 represents an integer of 1 to 3; d1 represents an integer of 0 to 6; where d1 represents 0, B is a single bond.

The radical represented by the formula (3-2) is shown below.

In formula (3-2), e1 represents an integer of 0 to 6.

The base represented by the formula (3-3) is shown below.

In formula (3-3), D represents an oxygen atom or a single bond; f1 represents an integer from 1 to 3; g1 represents an integer from 0 to 6, wherein when g1 represents 0, D is a single bond; E represents a hydrogen atom or carbon The number is 1 to 6 alkyl groups.

The epoxy group as W ⁶ and W ¹³ preferably includes a group represented by the formula (3-1-1), a group represented by the formula (3-1-2), and a group represented by the formula (3-2-1). At least one of a group represented by Formula, a group represented by Formula (3-3-1), and a group represented by Formula (3-3-2).

Specific examples of the compound represented by the formula (2-1) include at least one of compounds represented by the formula (2-1-1) to the formula (2-1-34).

, W and W ⁶ in the formula (2-1) represented by ^1, W the same as the formula (2-1-1) to formula (2-1-34) W ^{1 6,} and f represents an integer of 1 to 10 .

The alkyl group having a carbon number of 1 to 40 for W ⁸ in the above formula (2-2) is preferably an alkyl group having a carbon number of 1 to 20, wherein a part or all of the hydrogen atoms of the alkyl group may be Fluorine atom substitution. Examples of the alkyl group include the groups listed as the alkyl group of W ¹ in the formula (2-1). Examples of the monovalent alicyclic organic group having a carbon number of 3 to 40 of W ⁸ include cholestenyl, cholestyl, and adamantyl.

Examples of the divalent aromatic group, heterocyclic group, or fused ring group of W ⁹ and W ¹¹ include the divalent aromatic groups of W ³ and W ⁵ in the formula (2-1). Listed groups.

Specific examples of the compound represented by the formula (2-2) include formula (2-2-1) to formula At least one of the compounds represented by (2-2-11).

W of formula (2-2-1) to (2-2-11) in W ^8, W ^{13 is} the formula (2-2) ^8, W ^{13 is} the same, and q represents an integer of 1 to 10 .

Epoxy-containing cinnamic acid derivative (a-2) is preferably composed of formula (2-1-3), formula (2-1-9), formula (2-1-11), formula (2-1 -23), formula (2-1-24), formula (2-1-30), formula (2-2-2), formula (2-2-7), formula (2-2-9) Compound, or a combination of the above.

Based on the total amount of the silane monomers in the first mixture being 1 mole, the epoxy group-containing cinnamic acid derivative (a-2) is used in an amount of 0.1 mole to 0.95 mole, It is preferably 0.2 mol to 0.95 mol, and more preferably 0.3 mol to 0.9 mol.

When the photo-alignable polysiloxane (A) contained in the liquid crystal alignment agent is not used with the epoxy group-containing cinnamic acid derivative (a-2), the liquid crystal alignment agent has poor light stability and poor brightness stability.

Preparation method of photo-alignable polysiloxane (A)

The photo-alignable polysiloxane (A) used in the present invention can be obtained by allowing the polysiloxane (a-1) containing an acid anhydride group and the cinnamic acid derivative (a-2) containing an epoxy group in the presence of a catalyst. Down reaction synthesis.

As the catalyst, an organic salt or a known compound such as a hardening accelerator that can accelerate the reaction between the epoxy compound and the acid anhydride can be used.

Examples of the organic salt include primary or secondary organic amines such as ethylamine, diethylamine, piperazine, piperidine, pyrrolidine, and pyrrole; triethylamine, tri-n-propylamine, and tri-n-butylamine. Tertiary organic amines such as amines, pyridine, 4-dimethylaminopyridine, diazabicycloundecene, and tertiary organic amines such as tetramethylammonium hydroxide. Among these organic amines, tertiary organic amines such as triethylamine, tri-n-propylamine, tri-n-butylamine, pyridine, and 4-dimethylaminopyridine, or tetramethylammonium hydroxide, etc. are preferred. Grade organic amine.

Specific examples of the hardening accelerator include tertiary amines such as benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol, cyclohexyldimethylamine, and triethanolamine; Imidazole, 2-n-heptylimidazole, 2-n-alkylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl- 2-phenylimidazole, 1,2-dimethyl Imidazole, 2-ethyl-4-methylimidazole, 1- (2-cyanoethyl) -2-methylimidazole, 1- (2-cyanoethyl) -2-5-n-undecane Imidazole, 1- (2-cyanoethyl) -2-phenylimidazole, 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole, 2-phenyl-4-methyl Methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-bis (hydroxymethyl) imidazole, 1- (2-cyanoethyl) -2-phenyl-4,5-bis [(2 '-Cyanoethoxy) methyl] imidazole, 1- (2-cyanoethyl-2-n-undecylimidazolium trimellitate, 1- (2-cyanoethyl)- 2-phenylimidazolium trimellitate, 1- (2-cyanoethyl) -2-ethyl-4-methylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')] ethyl-S-triazine, 2,4-diamino-6- (2'-n-undecylimidazole) ethyl-S-triazine Trimeric isocyanate of 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1 ')] ethyl-S-triazine, 2-methylimidazole Adduct, Trimeric isocyanate adduct of 2-phenylimidazole, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')] ethyl-S-triazine Imidazole compounds such as trimeric isocyanate adducts; organic phosphorus compounds such as diphenylphosphine, triphenylphosphine, and triphenyl phosphite ; Benzyl triphenylphosphonium chloride, tetra-n-butylphosphonium bromide, methyltriphenylphosphonium bromide, ethyltriphenylphosphonium bromide, n-butyltriphenylphosphonium bromide Rhenium, tetraphenylphosphonium bromide, ethyltriphenylphosphonium iodide, ethyltriphenylphosphonium acetate, tetra-n-butylphosphonium-O, O-diethylphosphonium dithiosulfate (tetra- n-butyl phosphonium-O, O-diethyl phosphorodithionate), tetra-n-butylphosphonium benzotriazolate, tetra-n-butylphosphonium benzotriazolate, tetra-n-butylphosphonium tetrafluoroborate, tetra-n-butylphosphonium tetraphenyl Quaternary phosphonium salts such as borate, tetraphenylphosphonium tetraphenylborate, etc .; diazabicyclic olefins such as 1,8-diazabicyclo [5.4.0] undecene-7 or its organic acid salts; Zinc octoate, tin octoate, aluminum acetone aluminum complex Organometallic compounds such as acetylacetone complex); quaternary ammonium salts such as tetraethylammonium bromide, tetra-n-butylammonium bromide, tetraethylammonium chloride, and tetra-n-butylammonium chloride; trifluoride Boron compounds such as boron trifluoride and triphenyl borate; metal halogen compounds such as zinc chloride and tin tetrachloride; amine addition molding promotion such as dicyandiamide or adducts of amine and epoxy resin High-melting dispersion type latent hardening accelerator such as an agent; a microcapsule type latent hardening accelerator whose surface of the above-mentioned hardening accelerator such as an imidazole compound, an organic phosphorus compound, or a quaternary phosphonium salt is polymer-coated; Potential hardening accelerators such as amine salt-type latent hardening accelerators; Lewis acid salts, Bronsted acid salts (Bronsted acid salt), and other high-temperature dissociation-type thermal cationic polymerization-type latent hardening accelerators;

Specific examples of the hardening accelerator are preferably quaternary ammonium salts such as tetraethylammonium bromide, tetra-n-butylammonium bromide, tetraethylammonium chloride, and tetra-n-butylammonium chloride.

The polysiloxane (a-1) based on the acid anhydride group is 100 parts by weight, and the amount of the catalyst used is 100 parts by weight or less, preferably 0.01 to 100 parts by weight, and more preferably 0.1 to 20 parts by weight Serving.

The reaction temperature is preferably 0 ° C to 200 ° C, and more preferably 50 ° C to 150 ° C. The reaction time is preferably from 0.1 to 50 hours, and more preferably from 0.5 to 20 hours.

The synthesis reaction of the photo-alignable polysiloxane (A) can be performed in the presence of an organic solvent as needed. The organic solvent is not particularly limited, and may be the same as the organic solvent used in the preparation of the polysiloxane (a-1) containing an acid anhydride group and the solvent (B) contained in the liquid crystal alignment agent of the present invention. Not the same. Specific examples of the organic solvent are preferably 2-butanone, 2-hexanone, methyl isobutyl ketone, and n-butyl acetate. Ester, or a combination thereof.

The photo-alignable polysiloxane (A) has a weight average molecular weight of 5,000 to 50,000, preferably 6,000 to 48,000, and more preferably 7,000 to 45,000.

Solvent (B)

The solvent used in the liquid crystal alignment agent of the present invention is not particularly limited, as long as it can dissolve the photo-alignable polysiloxane (A) and other optional components and does not react therewith.

Specific examples of the solvent (B) include, but are not limited to, N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, 4-hydroxy-4-methyl-2-pentanone, and ethylene glycol Monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, Ethylene glycol isopropyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, Diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate Or N, N-dimethylformamide or N, N-dimethyl acetamide. The solvent (B) may be used alone or in combination.

The photo-alignment-based polysiloxane (A) is used in an amount of 100 parts by weight, and the solvent (B) is used in an amount of 800 to 4,000 parts by weight, preferably 800 to 3800 parts by weight, and more preferably 900 parts by weight to 3600 parts by weight.

Based on the total alignment of photo-alignable polysiloxane (A) and polymer composition (C) The use amount is 100 parts by weight, and the use amount of the solvent (B) is 800 to 4,000 parts by weight, preferably 800 to 3800 parts by weight, and more preferably 900 to 3600 parts by weight.

Polymerization composition (C)

The polymerization composition (C) is obtained by reacting a second mixture, and the mixture includes a tetracarboxylic dianhydride component (c-1) and a diamine component (c-2).

Specifically, the polymer composition (C) includes polyamidic acid, polyamidoimide, polyamido-polyamidoimide block copolymer, or a combination of these polymers. Among them, the polyfluorene-based block copolymer includes a polyfluoride-based block copolymer, a polyfluoride-based imide block copolymer, a polyfluoride-based polyimide-block copolymer, or the above-mentioned polymerization. Combination of things. The polyfluorinated acid polymer, the polyfluorinated imine polymer, and the polyfluorinated acid-polyfluorinated imide block copolymer can be selected from the tetracarboxylic dianhydride component (c-1) and the diamine component (c- 2) prepared by reacting the second mixture.

Tetracarboxylic dianhydride component (c-1)

The tetracarboxylic dianhydride compound (c-1) includes an aliphatic tetracarboxylic dianhydride compound, an alicyclic tetracarboxylic dianhydride compound, an aromatic tetracarboxylic dianhydride compound, and from formula (I-1) to formula ( At least one of the tetracarboxylic dianhydride compounds represented by I-6), or a combination thereof.

Specific examples of the aliphatic tetracarboxylic dianhydride compound, the alicyclic tetracarboxylic dianhydride compound, and the aromatic tetracarboxylic dianhydride compound are listed below, but the present invention is not limited to this. These specific examples.

Specific examples of the aliphatic tetracarboxylic dianhydride compound may include, but are not limited to, ethane tetracarboxylic dianhydride, butane tetracarboxylic dianhydride, or a combination thereof.

Specific examples of the alicyclic tetracarboxylic dianhydride compound may include, but are not limited to, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4- Cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,3-dichloro-1,2,3,4-cyclo Butane tetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentane tetracarboxylic acid Acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ', 4,4'-dicyclohexyltetracarboxylic dianhydride, cis-3,7-dibutyl Cyclopeptyl-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, or a combination of the foregoing compounds.

Specific examples of the aromatic tetracarboxylic dianhydride compound may include, but are not limited to, 3,4-dicarboxyl-1,2,3,4-tetrahydronaphthalene-1-succinic dianhydride, pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenylpyrenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid Acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ', 4,4'-diphenylethanetetracarboxylic dianhydride, 3,3', 4,4'- Dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3 ', 4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic dianhydride, 4, 4'-bis (3,4-dicarboxyphenoxy) diphenylsulfide dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylarsine dianhydride, 4,4'- Bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride (4,4'-bis (3,4-dicarboxy phenoxy) diphenylpropane dianhydride), 3,3 ', 4,4'-perfluoroisoprene Propyldiphthalic dianhydride, 3,3 ', 4,4'-diphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis (tris) Phenylphthalic acid) dianhydride, m-phenylene-bis (tris Phenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4'-diphenyl ether dianhydride, bis (triphenylphthalic acid) -4,4'-diphenylmethane Dianhydride, ethylene glycol-bis (anhydrotrimellitic acid ester), propylene glycol-bis (anhydrotrimellitic acid ester), 1,4-butanediol-bis (anhydrotrimellitic acid ester), 1,6 -Hexanediol-bis (dehydrated trimellitate), 1,8-octanediol-bis (dehydrated trimellitate), 2,2-bis (4-hydroxyphenyl) propane-bis (dehydrated Trimellitic acid ester), 2,3,4,5-tetrahydrofurantetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo Methyl-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione {(1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5 -dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione)}, 1,3,3a, 4,5,9b-hexahydro-5-methyl-5- (tetrahydro -2,5-dioxo-3-furyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro- 5-ethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a , 4,5,9b-hexahydro-7-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1, 3-dione, 1,3,3a, 4,5,9b-hexahydro-7-ethyl-5- (tetrahydro-2,5-dioxo-3-furyl) -Naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5- Dioxo-3-furyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-ethyl- 5- (tetrahydro-2,5-dioxo-3-furyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5, 9b-hexahydro-5,8-dimethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3- Aromatic tetracarboxylic dianhydride compounds such as dione, 5- (2,5-dioxotetrahydrofuranyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, or the above compounds The combination.

The tetracarboxylic dianhydride compounds represented by formula (I-1) to formula (I-6) are as follows Show.

In Formula (I-5), A ¹ represents a divalent group containing an aromatic ring; r represents an integer of 1 to 2; A ² and A ³ may be the same or different, and each may independently represent a hydrogen atom or an alkyl group. Specific examples of the tetracarboxylic dianhydride compound represented by the formula (I-5) include at least one of compounds represented by the formula (I-5-1) to the formula (I-5-3).

In Formula (I-6), A ⁴ represents a divalent group containing an aromatic ring; A ⁵ and A ⁶ may be the same or different, and each independently represents a hydrogen atom or an alkyl group. The tetracarboxylic dianhydride compound represented by the formula (I-6) is preferably a compound represented by the formula (I-6-1).

The tetracarboxylic dianhydride compound (c-1) may be used alone or in combination.

Specific examples of the tetracarboxylic dianhydride compound (c-1) preferably include 1,2,3,4-cyclobutane tetracarboxylic dianhydride (1,2,3,4-cyclobutane tetracarboxylic dianhydride), 1, 2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl vinegar Acid dianhydride (2,3,5-tricarboxycyclopentylacetic dianhydride), 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydronaphthalene- 1-succinic dianhydride, pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-linked Phenylhydrazine tetracarboxylic dianhydride, a compound represented by formula (I-1), or a combination thereof.

The total mole number based on the diamine component (c-2) is 100 moles, and the usage amount of the tetracarboxylic dianhydride component (c-1) is preferably from 20 moles to 200 moles, more preferably 30 mol to 120 mol.

Diamine component (c-2)

The diamine component (c-2) includes a diamine compound (c-2-1).

Diamine compound (c-2-1)

The diamine compound (c-2-1) includes an aliphatic diamine compound, an alicyclic diamine compound, an aromatic diamine compound, a diamine compound represented by formula (II-1) to formula (II-30), Or a combination.

Specific examples of the aliphatic diamine compound include, but are not limited to, 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane , 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane , 4,4'-diaminoheptane, 1,3-diamino-2,2-dimethylpropane, 1,6-diamino-2,5-dimethylhexane, 1,7 -Diamino-2,5-dimethylheptane, 1,7-diamino-4,4-dimethylheptane, 1,7-diamino-3-methylheptane, 1, 9-diamino-5-methylnonane, 2,11-diaminododecane, 1,12-diaminooctadecane, 1,2-bis (3-aminopropyl Oxy) ethane, or a combination thereof.

Specific examples of the alicyclic diamine compound include, but are not limited to, 4,4'-diaminodicyclohexylmethane, 4,4'-diamino-3,3'-dimethyldicyclohexylamine, 1, 3-diaminocyclohexane, 1,4-diaminocyclohexane, isophorone diamine, tetrahydrodicyclopentadiene diamine, tricyclo [6.2.1.0 ^2,7 ] -unda Carbenedimethyldiamine, 4,4'-methylenebis (cyclohexylamine), or a combination thereof.

Specific examples of the aromatic diamine compound include, but are not limited to, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4'-diaminodiphenyl Fluorene, 4,4'-diaminobenzidineaniline, 4,4'-diaminostilbene, 4,4'-diaminodiphenyl ether, 3,4'-diaminediamine Phenyl ether, 3,3'-diaminochalcone, 1,5-diaminonaphthalene, 5-amino-1- (4'-aminophenyl) -1,3,3-trimethyl Indanes, 6-amino-1- (4'-aminophenyl) -1,3,3-trimethylhydroindene, hexahydro-4,7-methyl bridged indenyl dimethylene Diamine, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenylphenyl) ) Hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] fluorene, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4 -Aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9-bis (4-aminophenyl) -10-hydroanthracene, 9,10-bis ( 4-aminophenyl) anthracene [9,10-bis (4-aminophenyl) anthracene], 2,7-diaminofluorene, 9,9-bis (4-aminophenyl) , 4,4'-methylene-bis (2-chloroaniline), 4,4 '-(p-phenylene isopropylidene) bisaniline, 4,4'-(m-phenylene isopropylidene) Propyl) bisaniline, 2,2'-bis [4- (4-amino-2-trifluoromethylphenoxy) phenyl] hexafluoropropane, 4,4'-bis [(4-amino -2-trifluoromethyl) phenoxy] -octafluorobiphenyl, 5- [4- (4-n-pentylcyclohexyl) cyclohexyl] phenyl-methylene-1,3-diaminobenzene {5- [4- (4-n-pentylcyclohexyl) cyclohexyl] phenylmethylene- 1,3-diamino benzene}, 1,1-bis [4- (4-aminophenoxy) phenyl] -4- (4-ethylphenyl) cyclohexane {1,1-bis [4 -(4-aminophenoxy) phenyl] -4- (4-ethylphenyl) cyclohexane}, or a combination thereof.

The diamine compounds represented by the formula (II-1) to the formula (II-30) are shown below.

In formula (II-1), B ¹ represents -O-, ,or ; B ² represents a group having a steroid (cholesterol) skeleton, a trifluoromethyl group, a fluorine atom, an alkyl group having 2 to 30 carbon atoms, or derived from pyridine, pyrimidine, triazine, piperidine, or piperazine, etc. A monovalent group containing a nitrogen atom ring structure.

Specific examples of the compound represented by the formula (II-1) include, but are not limited to, 2,4-diaminophenyl ethyl formate, 3,5-diaminophenyl ethyl formate Ester (3,5-diaminophenyl ethyl formate), 2,4-diaminophenyl propyl formate, 3,5-diaminophenyl propyl formate (3,5- diaminophenyl propyl formate), 1-dodecoxy-2,4-diaminobenzene, 1-dodecoxy-2,4-diaminobenzene, 1-dodecoxy-2,4-diaminobenzene ( 1-hexadecoxy-2,4-diaminobenzene), 1-octadecyloxy-2,4- At least one kind of a 1-octadecoxy-2,4-diaminobenzene, a compound represented by a formula (II-1-1) to a formula (II-1-6), or a combination of the said compounds.

The compounds represented by the formula (II-1-1) to the formula (II-1-6) are shown below.

, B ¹ same formula (II-2) with the formula B (II-1) is ^1, B ³ and B ⁴ each independently represents a divalent aliphatic ring, a divalent aromatic ring or a divalent heterocyclic group; B ⁵ represents an alkyl group having 3 to 18 carbons, an alkoxy group having 3 to 18 carbons, a fluoroalkyl group having 1 to 5 carbons, a fluoroalkoxy group having 1 to 5 carbons, cyano or Halogen atom.

Specific examples of the compound represented by the formula (II-2) include at least one of compounds represented by the formula (II-2-1) to the formula (II-2-13). Specifically, the compounds represented by formula (II-2-1) to formula (II-2-13) are shown below.

In the formulae (II-2-10) to (II-2-13), s represents an integer of 3 to 12.

In formula (II-3), B ⁶ each independently represents a hydrogen atom, a fluorenyl group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, an alkoxy group or a halogen atom having 1 to 5 carbon atoms, And B ⁶ in each repeating unit may be the same or different; p represents an integer of 1 to 3.

Specific examples of the compound represented by the formula (II-3) include when p is 1: p-diaminebenzene, m-diaminebenzene, o-diaminebenzene, 2,5-diaminotoluene, etc .; when p When 2: 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-di Aminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diaminobiphenyl, 3,3'- Dichloro-4,4'-diaminobiphenyl, 2,2 ', 5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4' -Diamino-5,5'-dimethoxybiphenyl or 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, etc .; or when p is 3: 1 , 4-bis (4'-aminophenyl) benzene and the like.

Specific examples of the compound represented by the formula (II-3) preferably include p-diaminebenzene, 2,5-diaminotoluene, 4,4'-diaminobiphenyl, 3,3'-dimethyl Oxy-4,4'-diaminobiphenyl, 1,4-bis (4'-aminophenyl) benzene or a combination of the foregoing.

In Formula (II-4), v represents an integer of 2 to 12.

In Formula (II-5), r represents an integer of 1 to 5. The compound represented by the formula (II-5) is preferably 4,4'-diamino-diphenylsulfide.

In formula (II-6), B ⁷ and B ⁹ each independently represent a divalent organic group, and B ⁷ and B ⁹ may be the same or different; B ⁸ represents a derivative derived from pyridine, pyrimidine, triazine, piperidine, or piperidine Divalent group of a cyclic structure containing a nitrogen atom such as a azine.

In formula (II-7), B ¹⁰ , B ¹¹ , B ¹² and B ¹³ each independently represent a hydrocarbon group having a carbon number of 1 to 12, and B ¹⁰ , B ¹¹ , B ¹² and B ¹³ may be the same or different; X1 Each independently represents an integer of 1 to 3; X2 represents an integer of 1 to 20.

In formula (II-8), B ¹⁴ represents an oxygen atom or a cyclohexyl group; B ¹⁵ represents a methylene group (methylene, -CH _2- ); B ¹⁶ represents a phenylene group or a cyclohexane group; B ¹⁷ Represents a hydrogen atom or a heptyl group.

Specific examples of the compound represented by the formula (II-8) include a compound represented by the formula (II-8-1), a compound represented by the formula (II-8-2), or a combination thereof.

The compounds represented by the formula (II-9) to the formula (II-30) are shown below.

In the formulae (II-17) to (II-25), B ^{18 is} preferably an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms; B ^{19 is} preferably a hydrogen atom An alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms.

The diamine compound (c-2-1) can be used alone or in combination.

Specific examples of the diamine compound (c-2-1) preferably include, but are not limited to, 1,2-diaminoethane, 3,3'-diaminochalcone, 4,4'-diamine Stilbene, 4,4'-diaminodicyclohexylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 5- [4- ( 4-n-pentylcyclohexyl) cyclohexyl] phenylmethylene-1,3-diaminobenzene, 1,1-bis [4- (4-aminophenoxy) phenyl] -4- (4-ethylphenyl) cyclohexane, ethyl 2,4-diaminophenylcarboxylate, 1-octadecyloxy-2,4-diaminobenzene, and the formula (II-1-1 ), A compound represented by formula (II-1-2), a compound represented by formula (II-1-4), a compound represented by formula (II-1-5), a compound represented by formula (II-2 -1) compound, compound represented by formula (II-2-11), p-diaminebenzene, m-diaminebenzene, o-diaminebenzene, compound represented by formula (II-8-1) A compound represented by the formula (II-26) to the formula (II-30), or a combination thereof.

Based on the total use amount of the photo-alignable polysiloxane (A) and the polymer composition (C) is 100 parts by weight, the use amount of the polymer composition (C) may be 1 to 99 parts by weight, preferably 3 95 parts by weight, and more preferably 5 to 90 parts by weight Parts by weight.

When the liquid crystal alignment agent contains the polymer composition (C), the brightness stability of the liquid crystal display element can be further improved.

Preparation method of polymer composition (C)

The polymerization composition (C) may include at least one of polyamidic acid and polyamidoimine. The polymerization composition (C) may further include a polyfluorene-imide-based block copolymer. The methods for preparing the various polymers described above are further described below.

Method for preparing polyamic acid

The method for preparing polyamic acid is to first dissolve the mixture in a solvent, wherein the second mixture includes a tetracarboxylic dianhydride component (c-1) and a diamine component (c-2), and the temperature is from 0 ° C to 100 ° C. The polycondensation reaction was performed at a temperature of ° C. After reacting for 1 hour to 24 hours, the reaction solution is distilled under reduced pressure using an evaporator to obtain polyamic acid. Alternatively, the reaction solution is poured into a large amount of a lean solvent to obtain a precipitate. Then, the precipitate is dried under reduced pressure to obtain polyamic acid.

The solvent used in the polycondensation reaction may be the same as or different from the solvent in the liquid crystal alignment agent described below, and the solvent used in the polycondensation reaction is not particularly limited as long as it can dissolve the reactant and the product. The solvent preferably includes, but is not limited to (1) an aprotic polar solvent, such as: N-methyl-2-pyrrolidinone (NMP), N, N-dimethylacetamide, Inferior substances such as N, N-dimethylformamide, dimethylmethylene, γ-butyrolactone, tetramethylurea or hexamethyltriamine phosphate Child-based polar solvents; or (2) phenol-based solvents, such as phenol-based solvents such as m-cresol, xylenol, phenol, or halogenated phenols. The use amount of the solvent used in the polycondensation reaction is preferably 200 parts by weight to 2000 parts by weight, and more preferably 300 parts by weight to 1800 parts by weight based on the total use amount of the mixture.

It is worth noting that in the polycondensation reaction, an appropriate amount of a lean solvent can be used in combination with the solvent, wherein the lean solvent does not cause the polyamic acid to precipitate. The lean solvent can be used singly or in combination, and it includes but is not limited to (1) alcohols, such as: methanol, ethanol, isopropanol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butane Alcohols or alcohols such as triethylene glycol; (2) ketones, such as: ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone; (3) esters, such as: Esters such as methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate, diethyl malonate, or ethylene glycol ethyl ether acetate; (4) ethers, such as diethyl ether, Ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethylene glycol isopropyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether, or diethylene glycol dimethyl ether Ethers such as alkyl ethers; (5) halogenated hydrocarbons, such as: dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, or o-dichloro Halogenated hydrocarbons such as benzene; or (6) hydrocarbons, for example: hydrocarbons such as tetrahydrofuran, hexane, heptane, octane, benzene, toluene or xylene, or any combination of the above solvents. Based on the use amount of the diamine component (c-2) being 100 parts by weight, the use amount of the lean solvent is preferably 0 to 60 parts by weight, and more preferably 0 to 50 parts by weight.

Method for preparing polyfluorene

The method for preparing polyimide is prepared by the method for preparing polyamidic acid The polyphosphonic acid is obtained by heating in the presence of a dehydrating agent and a catalyst. During the heating process, the arsenic acid functional group in the polyarsenic acid can be converted into the arsonimine functional group (ie, arsonimation) via a dehydration ring-closure reaction.

The solvent used in the dehydration ring-closing reaction may be the same as the solvent (B) in the liquid crystal alignment agent, so it will not be repeated here. The amount of the solvent used in the dehydration ring-closing reaction is preferably 200 to 2000 parts by weight, and more preferably 300 to 1800 parts by weight, based on 100 parts by weight of the polyamic acid used.

In order to obtain a better degree of polyimidation of the polyimide, the operating temperature of the dehydration ring-closing reaction is preferably 40 ° C to 200 ° C, and more preferably 40 ° C to 150 ° C. If the operating temperature of the dehydration ring-closing reaction is lower than 40 ° C, the imidization reaction is not complete, and the degree of imidization of the polyacid is reduced. However, if the operating temperature of the dehydration ring-closing reaction is higher than 200 ° C, the weight average molecular weight of the obtained polyfluorene imine is low.

The dehydrating agent used in the dehydration ring-closure reaction may be selected from acid anhydride compounds, and specific examples thereof include acid anhydride compounds such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride. Based on 1 mole of polyamic acid, the amount of dehydrating agent used is 0.01 to 20 moles. The catalyst used in the dehydration ring-closing reaction may be selected from (1) pyridine compounds, such as pyridine, trimethylpyridine, or dimethylpyridine; and (2) tertiary amine compounds, such as: Tertiary amines such as triethylamine. Based on the amount of dehydrating agent used is 1 mole, the amount of catalyst used can be 0.5 to 10 moles.

Method for preparing polyfluorene imide block copolymer

Polyimide block copolymers are selected from polyamidoblock copolymers Polymers, polyimide block copolymers, polyamic acid-polyimide block copolymers, or any combination of the foregoing polymers.

The method for preparing a polyfluorene-based block copolymer is preferably firstly dissolving a starting material in a solvent and performing a polycondensation reaction, wherein the starting material includes at least one polyamidic acid and / or at least one polyfluorene Imine, and may further include a carboxylic anhydride component and a diamine component.

The carboxylic acid anhydride component and the diamine component in the starting material may be the same as the tetracarboxylic dianhydride component (c-1) and the diamine component (c-2) used in the method for preparing a polyamic acid. The solvent used in the polycondensation reaction may be the same as the solvent used in the liquid crystal alignment agent described below, which is not repeated here.

The used amount of the solvent used in the polycondensation reaction is preferably 200 to 2000 parts by weight, and more preferably 300 to 1800 parts by weight based on the used amount of the starting material. The operating temperature of the polycondensation reaction is preferably 0 ° C to 200 ° C, and more preferably 0 ° C to 100 ° C.

The starting material preferably includes, but is not limited to, (1) two polyamido acids with different terminal groups and different structures; (2) two polyimines with different terminal groups and different structures; (3 ) Polyamidic acid and polyimide having different terminal groups and different structures; (4) Polyamidic acid, a carboxylic acid anhydride component, and a diamine component, among which the carboxylic acid anhydride component and the diamine component At least one of them is different from the structure of the carboxylic acid anhydride component and the diamine component used to form the polyamine acid; (5) the polyfluorene imine, the carboxylic acid anhydride component, and the diamine component, wherein the carboxylic acid anhydride group At least one of the component and the diamine component is different from the structure of the carboxylic acid anhydride component and the diamine component used to form the polyimide; (6) the polyamidic acid, the polyimide, and the carboxylic anhydride component versus A diamine component, wherein at least one of the carboxylic acid anhydride component and the diamine component is different from the structure of the carboxylic acid anhydride component and the diamine component used to form the polyamidic acid or the polyimide; (7 ) Two kinds of polyfluorinated acid, carboxylic anhydride and diamine components with different structures; (8) two kinds of polyfluorinated imine, carboxylic anhydride and diamine components with different structures; (9) two Polyamino acids and diamine components with different terminal groups being acid anhydride groups and different structures; (10) polyamino acids and carboxylic acid anhydride components with different terminal groups having amine groups and structural differences; (11) two A kind of polyfluorene imine and diamine components whose terminal groups are acid anhydride groups and different structures; or (12) two kinds of polyfluorene imine and carboxylic acid anhydride components whose terminal groups are amine groups and different structures.

As long as the efficacy of the present invention is not affected, the polyamidic acid, polyamidoimide, and polyamidoimide block copolymer are preferably terminally modified polymers after molecular weight adjustment. By using a terminal-modified polymer, the coating performance of the liquid crystal alignment agent can be improved. The method for preparing the terminal-modified polymer can be prepared by adding a polyfunctional compound while the polyamic acid is undergoing a polycondensation reaction.

Specific examples of monofunctional compounds include, but are not limited to (1) monobasic anhydrides, such as: maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecyl Monobasic anhydrides such as alkyl succinic anhydride or n-hexadecyl succinic anhydride; (2) monoamine compounds, such as: aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, N-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecanylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecanylamine, Monoamine compounds such as n-octadecylamine or n- eicosylamine; or (3) monoisocyanate compounds, such as monoisocyanate compounds such as phenyl isocyanate or naphthyl isocyanate.

Additive (D)

To the extent that the efficacy of the present invention is not affected, the liquid crystal alignment agent may optionally add an additive (D), wherein the additive (D) includes a compound having at least two epoxy groups, a silane compound having a functional group, Or a combination.

Compounds having at least two epoxy groups include, but are not limited to, 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-di Bromo neopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl- M-xylylenediamine, 1,3-bis (N, N-glycidylaminomethyl) cyclohexane, N, N, N ', N'-tetraglycidyl-4,4 '-Diaminodiphenylmethane, 3- (N, N-diepoxypropyl) aminopropyltrimethoxysilane, or a combination of the above compounds.

The compound having at least two epoxy groups may be used alone or in combination.

The photo-alignable polysiloxane (A) is used in an amount of 100 parts by weight or the total amount of the photo-alignable polysiloxane (A) and the polymer composition (C) is used in 100 parts by weight and has at least two rings The oxy compound may be used in an amount of 0 to 40 parts by weight, and preferably 0.1 to 30 parts by weight.

Specific examples of the silane compound having a functional group include, but are not limited to, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyl Trimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl)- 3-aminopropyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltrimethoxysilane, N-ethoxycarbonyl-3- Aminopropyltrimethoxysilane, N-ethoxycarbon-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxy Silylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazine, 10-triethoxysilyl-1,4,7-triazine, 9 -Trimethoxysilyl-3,6-diazinyl acetate, 9-triethoxysilyl-3,6-diazinyl acetate, N-benzyl-3-aminopropyltrimethyl Oxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethyl Oxysilane, N-bis (ethylene oxide) -3-aminopropyltrimethoxysilane, N-bis (ethylene oxide) -3-aminopropyltriethoxysilane, or a combination thereof.

The silane compound having a functional group may be used alone or in combination.

The use amount of the photo-alignable polysiloxane (A) is 100 parts by weight or the total use amount of the photo-alignable polysiloxane (A) and the polymer composition (C) is 100 parts by weight, and it has a functional group The silane compound may be used in an amount of 0 to 10 parts by weight, and preferably 0.5 to 10 parts by weight.

Based on 100 parts by weight of the photo-alignable polysiloxane (A) or 100 parts by weight of the total amount of the photo-alignable polysiloxane (A) and the polymer composition (C), the amount of the additive (D) The amount used is preferably 0.5 parts by weight to 50 parts by weight, and more It is preferably 1 part by weight to 45 parts by weight.

<Preparation method of liquid crystal alignment agent>

The method for preparing the liquid crystal alignment agent of the present invention is not particularly limited, and it can be prepared by a general mixing method. For example, the photo-alignable polysiloxane (A) and the polymer composition (C) prepared in the above manner are first mixed uniformly to form a mixture. Next, the solvent (B) is added under the condition of a temperature of 0 ° C. to 200 ° C., and the additive (D) is optionally added. Finally, the stirring is continued with a stirring device until the solvent is dissolved. In addition, it is preferable to add the solvent (B) at a temperature of 20 ° C to 60 ° C.

At 25 ° C, the viscosity of the liquid crystal alignment agent of the present invention is usually 15 cps to 35 cps, preferably 17 cps to 33 cps, and more preferably 20 cps to 30 cps.

<Method for preparing liquid crystal alignment film>

The liquid crystal alignment agent of the present invention can be suitably used for forming a liquid crystal alignment film by a photo-alignment method.

Methods for forming a liquid crystal alignment film include, for example, applying a liquid crystal alignment agent to a substrate to form a coating film, and irradiating the coating film with polarized or non-polarized radiation from a direction inclined with respect to the coating film surface; or from A method of irradiating the coating film with polarized radiation in a direction perpendicular to the film surface to impart liquid crystal alignment ability to the coating film.

First, the liquid crystal alignment agent of the present invention is applied to a substrate provided with a patterned transparent conductive film by a suitable coating method such as a roll coating method, a spin coating method, a printing method, or an ink-jet method. One side of the transparent conductive film. After coating, the coated surface is subjected to A pre-bake treatment is followed by a post-bake treatment, thereby forming a coating film. The purpose of the above pre-baking treatment is to volatilize the organic solvent in the pre-coating layer. The conditions for the pre-baking treatment are, for example, 0.1 to 5 minutes at 40 to 120 ° C. The conditions of the post-baking treatment are preferably at 120 to 300 ° C, more preferably at 150 to 250 ° C, preferably for 5 to 200 minutes, and more preferably for 10 to 100 minutes. The film thickness of the post-bake coating film is preferably 0.001 to 1 μm, and more preferably 0.005 to 0.5 μm.

For the substrate, for example, glass such as float glass and soda lime glass; plastics such as polyethylene terephthalate, polybutylene terephthalate, polyether, or polycarbonate can be used. The formed transparent substrate and the like.

As the transparent conductive film, a NESA film formed of SnO ₂ , an ITO film formed of In ₂ O ₃ -SnO ₂ , and the like can be used. In order to form these transparent conductive film patterns, a photo-etching technique, a method of using a mask when forming the transparent conductive film, and the like can be used.

When the liquid crystal alignment agent is applied, in order to make the substrate, the transparent conductive film, and the coating film have better adhesion, a functional silane compound, titanate, or the like may be coated on the substrate and the transparent conductive film in advance.

Next, the coating film is irradiated with polarized light or non-polarized radiation to give liquid crystal alignment energy, and a liquid crystal alignment film is formed from the coating film. Here, the radiation may use, for example, ultraviolet rays and visible light including light having a wavelength of 150 to 800 nm, and preferably ultraviolet rays including light having a wavelength of 300 to 400 nm. When the radiation used is polarized light (linearly polarized light or partially polarized light), irradiation can be performed from a direction perpendicular to the coating film surface, and irradiation can also be performed from an oblique direction in order to provide a pretilt angle. On the other hand, in the photo When emitting non-polarized radiation, it is necessary to irradiate from a direction inclined with respect to the coating film surface.

As a light source for radiating radiation, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, or an excimer laser can be used. The ultraviolet rays in the aforementioned preferable wavelength region can be obtained by a method in which the aforementioned light source is used in combination with, for example, a filter, a diffraction grating, and the like.

Radiation irradiation amount is preferably 1J / m ² or more and less than 10000J / m ^2, more preferably 10 ~ 3000J / m ^2. In addition, when applying liquid crystal alignment energy to a coating film formed of a conventionally known liquid crystal alignment agent by a photo-alignment method, a radiation irradiation amount of 10,000 J / m ² or more is required. However, if the liquid crystal alignment agent of the present invention, even if the light distribution irradiated amount of radiation when the method of 3000J / m ² or less, and further 1000J / m ² or less, and further is 300J / m ² or less, can impart good Liquid crystal alignment can help reduce the manufacturing cost of liquid crystal display elements.

<Liquid crystal display element and manufacturing method thereof>

The liquid crystal display element of the present invention includes a liquid crystal alignment film formed of the liquid crystal alignment agent of the present invention. The liquid crystal display element of this invention can be manufactured as follows.

Two substrates having the liquid crystal alignment film formed as described above were prepared, and liquid crystal was arranged between the two substrates to manufacture a liquid crystal cell. In order to manufacture a liquid crystal cell, the following two methods can be cited, for example.

The first method: First, two substrates are arranged opposite to each other across a gap (cell gap) so that the respective liquid crystal alignment films face each other; a sealant is used to align the two substrates. Peripheral parts are bonded together; liquid crystal is injected into the cell gap divided by the substrate surface and the sealant; and the injection hole is closed, so that a liquid crystal cell can be manufactured.

The second method: a method called a One Drop Fill (ODF) method. First, a predetermined position on one of the two substrates forming the liquid crystal alignment film is coated with, for example, an ultraviolet curable sealing material; the liquid crystal is dropped on the liquid crystal alignment film surface; then, the other substrate is bonded so that the liquid crystal alignment film faces each other. Next, the entire surface of the substrate is irradiated with ultraviolet rays to cure the sealant, whereby a liquid crystal cell can be manufactured.

In the case of using any of the above methods, it is desirable to subsequently heat the liquid crystal cell to a temperature at which the liquid crystal used is an isotropic phase, and then slowly cool it to room temperature, thereby removing the flow alignment when filling the liquid crystal.

Then, by bonding a polarizing plate to the outer surface of the liquid crystal cell, the liquid crystal display element of the present invention can be obtained. Here, when the liquid crystal alignment film is horizontally aligned, by adjusting the angle of the polarization direction of the linearly polarized radiation radiated in the two substrates on which the liquid crystal alignment film is formed, and the angle of each substrate and the polarizing plate, a TN type can be obtained. Or STN type liquid crystal cell. On the other hand, when the liquid crystal alignment film is vertically aligned, the direction of the easy-to-align axis of the two substrates on which the liquid crystal alignment film is formed is made parallel by constituting the liquid crystal cell, and the polarizing plate and the The liquid crystal cells are bonded together so that the polarization direction of the liquid crystal cells is at an angle of 45 ° with the alignment easy axis, and a liquid crystal display element having a vertical alignment type liquid crystal cell can be formed.

As the sealant, for example, an epoxy resin containing a curing agent and alumina balls as a spacer can be used.

Specific examples of the liquid crystal include a nematic liquid crystal and a dish-shaped liquid crystal.

In the case of a TN-type or STN-type liquid crystal cell, a nematic liquid crystal having positive dielectric anisotropy is preferred, and for example, biphenyl-based liquid crystals (biphenyl-based liquid crystals), phenylcyclohexane-based liquid crystals ( phenyl cyclohexane-based liquid crystal), ester liquid crystals, terphenyl liquid crystals, biphenyl cyclohexane-based liquid crystals, pyrimidine-based liquid crystals, Dioxane-based liquid crystals, bicyclooctane-based liquid crystals, cubic-based liquid crystals, and the like. In addition, a cholesteric liquid crystal such as cholesteryl chloride, cholesteryl nonanoate, and cholesteryl carbonate may be further added to the liquid crystal; Chiral agents sold under the trade names "C-15" and "CB-15" (Merck); p-decyloxymethylene-p-amino-2-methylbutyl cinnamate (p -decyloxybenzylidene-p-amino-2-methyl butyl cinnamate) and other ferroelectric liquid crystals are used.

On the other hand, in the case of a vertically aligned liquid crystal cell, a nematic liquid crystal having a negative dielectric anisotropy is preferred, and for example, dicyanobenzene-based liquid crystal, pyridazine-based liquid crystal can be used (pyridazine-based liquid crystal), Schiff base-based liquid crystal, azoxy-based liquid crystal, biphenyl-based liquid crystal, phenyl ring Hexane liquid crystal cyclohexane-based liquid crystal).

The polarizing plate used on the outside of the liquid crystal cell includes a polarizing film called "H film" obtained by sandwiching a polyvinyl acetate with polyvinyl alcohol as a sandwich between a protective film of cellulose acetate and an orientation film. A polarizing plate or a polarizing plate formed by the H film itself.

The thus-produced liquid crystal display element of the present invention is excellent in display performance and does not deteriorate even if it is used for a long time.

FIG. 1 is a side view of a liquid crystal display element according to an embodiment of the present invention. The liquid crystal display element 100 includes a first unit 110, a second unit 120, and a liquid crystal unit 130. The second unit 120 is disposed separately from the first unit 110, and the liquid crystal unit 130 is disposed between the first unit 110 and the second unit 120.

The first unit 110 includes a first substrate 112, a first conductive film 114, and a first liquid crystal alignment film 116, wherein the first conductive film 114 is located between the first substrate 112 and the first liquid crystal alignment film 116, and the first liquid crystal alignment film 116 is located on one side of the liquid crystal cell 130.

The second unit 120 includes a second substrate 122, a second conductive film 124, and a second liquid crystal alignment film 126, wherein the second conductive film 124 is located between the second substrate 122 and the second liquid crystal alignment film 126, and the second liquid crystal alignment film 126 is located on the other side of the liquid crystal cell 130. In other words, the liquid crystal cell 130 is located between the first liquid crystal alignment film 116 and the second liquid crystal alignment film 126.

The first substrate 112 and the second substrate 122 are selected from transparent materials. The transparent materials include, but are not limited to, alkali-free glass, soda-lime glass, hard glass (Pales glass), and quartz glass used in liquid crystal display devices. , Polyethylene terephthalate, polybutylene terephthalate, polyether fluorene or polycarbonate. The materials of the first conductive film 114 and the second conductive film 124 are selected from tin oxide (SnO ₂ ), indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), and the like.

Each of the first liquid crystal alignment film 116 and the second liquid crystal alignment film 126 is the above-mentioned liquid crystal alignment film, and its role is to form a pretilt angle of the liquid crystal cell 130. In addition, when a voltage is applied to the first conductive film 114 and the second conductive film 124, an electric field may be generated between the first conductive film 114 and the second conductive film 124. This electric field can drive the liquid crystal cell 130, thereby changing the arrangement of liquid crystal molecules in the liquid crystal cell 130.

The present invention will be further described with reference to the following examples, but it should be understood that these examples are merely illustrative and should not be construed as limitations of the implementation of the present invention.

Synthesis Example and Comparative Synthesis Example of Photo-Aligned Polysiloxane (A)

The following describes synthesis examples A-1 to A-12 of photo-alignable polysiloxane (A) (also referred to as polysiloxane (A)):

Synthesis Example A-1

A 500 ml three-necked flask was equipped with a stirrer, a condenser, and a thermometer. Then, in a three-necked flask, 0.30 mole of 3- (trimethoxysilyl) propylsuccinic anhydride (hereinafter referred to as X-12-967) and 0.30 mole of methyltrimethoxysilane (methyltrimethoxysilane) were added. silane (hereinafter referred to as MTMS), 0.40 mole of phenyltrimethoxy silane (hereinafter referred to as PTMS) and 600 g of propylene glycol monomethyl ether (hereinafter referred to as PGME), and stirred at room temperature Add triethylamine (hereinafter referred to as TEA) aqueous solution (20 g TEA / 200 g H ₂ O) within 30 minutes. Next, the three-necked flask was immersed in an oil bath at 30 ° C. and stirred for 30 minutes, and then the oil bath was heated to 90 ° C. within 30 minutes. When the internal temperature of the solution reached 75 ° C., the mixture was continuously heated and stirred for 6 hours . After the reaction is completed, the organic layer is taken out and washed with a 0.2% by weight ammonium nitrate aqueous solution to obtain a solution containing a polysiloxane compound.

Next, 0.10 mol of epoxy-containing cinnamic acid derivative (a-2-1) and 0.2 g of a hardening accelerator UCAT 18X (manufactured by SAN-APRO) were added to the polysiloxane-containing compound. Solution. Then, the three-necked flask was immersed in an oil bath at 30 ° C. and stirred for 10 minutes, and then the oil bath was heated to 115 ° C. within 30 minutes. When the internal temperature of the solution reached 100 ° C., heating and stirring were continued for 24 hours. After the reaction is completed, the organic layer is taken out, washed with water, dried with magnesium sulfate, and the solvent is removed to obtain polysiloxane (A-1).

Synthesis Example A-2 to Synthesis Example A-12

The polysiloxane (A) of Synthesis Example A-2 to Synthesis Example A-12 (that is, Polysiloxane A-2 to Polysiloxane A-12) was prepared in the same procedure as in Synthesis Example A-1. It is prepared, and its difference lies in: changing the silane monomer component, solvent, catalyst and its usage amount, reaction temperature and polycondensation time of polysiloxane (A) (as shown in Table 1).

Comparative Synthesis Example A'-1 to Comparative Synthesis Example A'-5

Comparative Synthesis Example A'-1 to Comparative Synthesis Example A'-5 The polysiloxanes (A'-1) to Polysiloxane (A'-5) were prepared in the same procedure as in Synthesis Example A-1 And the difference lies in: changing the type of silane monomer and its use amount, the type of cassia carboxy derivative and its use amount, the type of catalyst and solvent and its use amount, reaction temperature and polycondensation time (see Table 1 (Shown), in which the type of the silane monomer and the type of the cassia carboxy derivative are changed, for example, in the reaction for obtaining a photo-alignable polysiloxane, no polysiloxane containing an acid anhydride group and / or no epoxy group is used. Cinnamic acid derivative (a-2).

Preparation example of epoxy-containing cinnamic acid derivative (a-2)

Hereinafter, the epoxy group-containing cinnamic acid derivatives (a-2-1) to (a) in Synthesis Example A-1 to Synthesis Example A-12 and Comparative Synthesis Example A'-1 to Comparative Synthesis Example A'-5 will be described. -2-5) Preparation example.

Production Example a-2-1

Production Example a-2-1 is an epoxy group-containing cinnamic acid derivative (a-2-1) synthesized according to the following reaction formula.

In a 500 ml three-necked flask, 9.91 g of 4-pentyl-trans-cyclohexylcarboxylic acid, 100 ml of thionyl chloride and 77 μl of N, N-dimethylformamide were sequentially added, and Stir at 80 ° C for 1 hour. Next, thionyl chloride was removed by distillation under reduced pressure, and then dichloromethane was added, followed by washing with an aqueous sodium hydrogen carbonate solution, drying with magnesium sulfate, and concentration. Then, tetrahydrofuran was added to prepare a solution (a-2-1- a).

In another 500 ml three-necked flask, 7.39 g of 4-hydroxycinnamic acid, 13.82 g of potassium carbonate, 0.48 g of tetrabutylammonium, 50 ml of tetrahydrofuran, and 100 ml of water were added. After the aqueous solution was cooled with ice, the solution (a-2-1-a) prepared above was slowly added dropwise, and reacted with stirring for 2 hours. After the reaction is over, add The reaction mixture was neutralized with hydrochloric acid, and extracted with ethyl acetate. The organic layer was washed with water, dried over magnesium sulfate, and then concentrated, and then recrystallized using ethanol to obtain a cinnamic acid compound (a-2-1-b).

To 5.66 g (0.10 mole) of potassium hydroxide dissolved in 50 ml of deionized water and heated to 50 ° C to 60 ° C, 34.4 g (0.10 mole) of cinnamic acid compound (a-2-1- b). The obtained reaction slurry was dried in a vacuum oven at 40 ° C to 50 ° C to obtain potassium cinnamate (a-2-1-c).

Potassium cinnamate ((a-2-1-c); 10.7 g; 0.028 mol) and tetrabutylammonium bromide (0.85 g; 2.7 mmol) as a catalyst were added to a device equipped with a mechanical stirrer and a reflux device In 50 g (0.54 mol) of epichlorohydrin in a reaction tank, and heated at 95 ° C to 105 ° C, react for 60 minutes to form a mixture. The mixture was then cooled to room temperature, diluted with 55 ml of chloroform and filtered to remove solid precipitate. The filtrate of the organic matter was washed with 5% sodium bicarbonate (NaHCO ₃ ) and deionized water in this order, and the obtained organic layer was distilled under reduced pressure at 30 ° C. to 40 ° C. to obtain epoxy group-containing cinnamic acid derivative (a-2-1) .

Production Example a-2-2

Production Example a-2-2 is an epoxy group-containing cinnamic acid derivative (a-2-2) synthesized according to the following reaction formula.

A 2-liter three-necked flask equipped with a thermometer and a nitrogen introduction tube was charged with 22 g of 4-iodophenol, 16 g of hexyl acrylate, 14 ml of triethylamine, and 2.3 g of tetrakis (triphenylphosphine). Palladium and 1 liter of N, N-dimethylformamide were introduced, and nitrogen was introduced to dry the inside of the bottle sufficiently. Then, the above mixture was heated to 90 ° C. and stirred under a stream of nitrogen for 2 hours to perform a reaction. After the reaction was completed, dilute hydrochloric acid was added to neutralize the reaction mixture, followed by extraction with ethyl acetate. The organic layer was washed with water, dried over magnesium sulfate, and then concentrated, and then recrystallized using ethanol to obtain a compound (a-2-2-a).

Next, 12 g of the above-mentioned compound (a-2-2-a), 5.5 g of succinic anhydride, and 0.6 g of 4-dimethyl were placed in a 200-ml three-necked flask equipped with a thermometer, a nitrogen introduction tube, and a reflux tube. Aminopyridine was introduced into the bottle to dry the inside. Next, 5.6 g of triethylamine and 100 ml of tetrahydrofuran were added to the mixture, and reacted under reflux for 5 hours. After the reaction was completed, dilute hydrochloric acid was added to neutralize the reaction mixture, followed by extraction with ethyl acetate. The organic layer was washed with water, dried over magnesium sulfate, and then concentrated, and then recrystallized using ethanol to obtain a cinnamic acid compound (a-2-2-b).

To 5.66 g (0.10 mole) of potassium hydroxide dissolved in 50 ml of deionized water and heated to 50 ° C to 60 ° C, 34.8 g (0.10 mole) of cinnamic acid compound (a-2-2- b). The obtained reaction slurry was dried in a vacuum oven at 40 ° C to 50 ° C to obtain potassium cinnamate (a-2-2-c).

Potassium cinnamate ((a-2-2-c); 10.8 g; 0.028 mol) and tetrabutylammonium bromide (0.85 g; 2.7 mmol) as catalyst were added to a device equipped with a mechanical stirrer and a reflux device In 50 g (0.54 mol) of epichlorohydrin in a reaction tank, and heated at 95 ° C to 105 ° C, react for 60 minutes to form a mixture. The mixture was then cooled to room temperature, diluted with 55 ml of chloroform and filtered to remove solid precipitate. The organic substance filtrate was washed with 5% sodium bicarbonate (NaHCO ₃ ) and deionized water in this order, and the obtained organic layer was distilled under reduced pressure at 30 ° C. to 40 ° C. to obtain epoxy group-containing cinnamic acid derivative (a-2-2). .

Production Example a-2-3

Preparation Example a-2-3 is an epoxy group-containing laurel synthesized according to the following reaction formula Derivatives (a-2-3).

In a 1-liter three-necked flask, 27.2 g of 4-hydroxyacetophenone, 27.6 g of potassium carbonate, 1.0 g of potassium iodide, and 500 ml of acetone were added. After stirring at room temperature for 30 minutes, 47.6 g of 1- Iodine-4,4,4-trifluorobutane was reacted under reflux in a nitrogen atmosphere for 5 hours. After the reaction is completed, the reaction solution is poured into water to precipitate the product, the obtained precipitate is filtered, and recrystallization is performed using acetone to obtain the compound (a-2-3-a).

23.2 g of the obtained compound (a-2-3-a), 15.0 g of 4-methylfluorenylbenzoic acid, 8.0 g of sodium hydroxide and 150 ml of ethanol were added to a 500 ml three-necked flask, and The reaction was carried out at reflux for 6 hours. After the reaction is completed, cool to room temperature, add 200 ml of water and stir until homogeneous. This solution was added to a 1-liter beaker, and concentrated hydrochloric acid was added dropwise while stirring until the pH of the solution was 7 or less. The precipitate formed in the beaker was filtered and recrystallized using ethanol to obtain 35 g of a cinnamic acid compound (a-2-3-b).

To 5.66 g (0.10 mole) of potassium hydroxide dissolved in 50 ml of deionized water and heated to 50 ° C to 60 ° C, 37.8 g (0.10 mole) of cinnamic acid compound (a-2-3- b). The obtained reaction slurry was dried in a vacuum oven at 40 ° C to 50 ° C to obtain potassium cinnamate (a-2-3-c).

Potassium cinnamate ((a-2-3-b); 11.6 g; 0.028 mol) and tetrabutylammonium bromide (0.85 g; 2.7 mmol) as catalyst were added to a device equipped with a mechanical stirrer and a reflux device In 50 g (0.54 mol) of epichlorohydrin in a reaction tank, and heated at 95 ° C to 105 ° C, react for 60 minutes to form a mixture. The mixture was then cooled to room temperature, diluted with 55 ml of chloroform and filtered to remove solid precipitate. The organic substance filtrate was washed with 5% sodium bicarbonate (NaHCO ₃ ) and deionized water in this order, and the obtained organic layer was distilled under reduced pressure at 30 ° C. to 40 ° C. to obtain epoxy group-containing cinnamic acid derivative (a-2-3). .

Production Example a-2-4

Production Example a-2-4 is an epoxy group-containing cinnamic acid derivative (a-2-4) synthesized according to the following reaction formula.

In a 1-liter three-necked flask, 24.4 g of 4-hydroxybenzaldehyde, 27.6 g of potassium carbonate, 1.0 g of potassium iodide, and 500 ml of acetone were added. After stirring at room temperature for 30 minutes, 30.2 g of 1-bromopentan was added. The alkane was reacted under reflux in a nitrogen atmosphere for 5 hours. After the reaction is completed, the reaction solution is poured into water to precipitate the product. The obtained precipitate was filtered and recrystallized using acetone to obtain a compound (a-2-4-a).

Take 19.2 g of the obtained compound (a-2-4-a), 16.4 g of 4-acetamidobenzoic acid, 8.0 g of sodium hydroxide and 150 ml of ethanol into a 500 ml three-necked flask, and reflux under The reaction was continued for 6 hours. After the reaction is completed, cool to room temperature, add 200 ml of water and stir until homogeneous. This solution was added to a 1-liter beaker, and concentrated hydrochloric acid was added dropwise while stirring until the pH of the solution was 7 or less. The precipitate formed in the beaker was filtered and recrystallized using ethanol to obtain a cinnamic acid compound (a-2-4-b).

In a 500 ml three-necked flask, 6.1 g (0.05 mol) of 3-ethyl-3-hydroxymethyl oxetane and 7.8 g (0.05 mol) were sequentially added. Ear) of 1-bromo-3-chloropropane, 100 microliters of dimethyl sulfoxide and 3 grams of sodium hydroxide, and stirred at 80 ° C for 1 hour . Next, the solution was washed with an aqueous sodium hydrogen carbonate solution, dried over magnesium sulfate, and concentrated. Then, tetrahydrofuran was added to prepare a solution (a-2-4-c).

In a 500 ml three-necked flask, 17 g of a cinnamic acid compound (a-2-4-b), 13.82 g of potassium carbonate, 0.48 g of tetrabutylammonium, 50 ml of tetrahydrofuran, and 100 ml of water were added. After the aqueous solution was cooled with ice, the solution (a-2-4-c) obtained above was slowly added dropwise, and reacted with stirring for 2 hours. After the reaction was completed, hydrochloric acid was added to neutralize the reaction mixture, followed by extraction with ethyl acetate. The organic layer was washed with water, dried over magnesium sulfate, and then concentrated, and then recrystallized using ethanol to obtain an epoxy group-containing cinnamic acid derivative (a-2-4).

Production Example a-2-5

Production Example a-2-5 is an epoxy group-containing cinnamic acid derivative (a-2-5) synthesized according to the following reaction formula.

In a 1-liter three-necked flask, 27.2 g of 4-hydroxyacetophenone, 27.6 g of potassium carbonate, 1.0 g of potassium iodide, and 500 ml of acetone were added. After stirring at room temperature for 30 minutes, 35.8 g of 1- Bromoheptane was reacted under reflux in a nitrogen atmosphere for 5 hours. After the reaction is completed, the reaction solution is poured into water to precipitate the product, and the resulting precipitate is filtered and recrystallized using acetone to obtain the compound (a-2-5-a).

23.4 g of the compound (a-2-5-a) obtained above, 15.0 g of 4-methylfluorenylbenzoic acid, 8.0 g of sodium hydroxide and 150 ml of ethanol were added to a 500 ml three-necked flask and refluxed. The reaction was continued for 6 hours. After the reaction is completed, cool to room temperature, add 200 ml of water and stir until homogeneous. Add this solution to a 1 liter beaker During the stirring, concentrated hydrochloric acid was added dropwise with stirring until the pH of the solution was 7 or less. The precipitate formed in the beaker was filtered and recrystallized using ethanol to obtain a cinnamic acid compound (a-2-5-b).

In a 500 ml three-necked flask, 18.3 g (0.05 mol) of cinnamic acid compound (a-2-5-b), 100 ml of thionyl chloride, and 77 μl of N, N-dichlorobenzene were sequentially added. Methylformamide and stirred at 80 ° C for 1 hour. Next, thionyl chloride was removed by distillation under reduced pressure, and then dichloromethane was added, followed by washing with an aqueous sodium hydrogen carbonate solution, drying with magnesium sulfate, and concentration. Then, tetrahydrofuran was added to prepare a solution (a-2-5- c).

In a 500 ml three-necked flask, 6.5 g of 7-oxabicyclo [4,1,0] heptane-3-methanol (7-Oxabicyclo [4.1.0] heptane-3-methanol) and 13.82 g of Potassium carbonate, 0.48 g of tetrabutylammonium, 50 ml of tetrahydrofuran and 100 ml of water. After the aqueous solution was cooled with ice, the solution (a-2-2-5-c) prepared above was slowly added dropwise, and reacted with stirring for 2 hours. After the reaction was completed, hydrochloric acid was added to neutralize the reaction mixture, followed by extraction with ethyl acetate. The organic layer was washed with water, dried over magnesium sulfate, and then concentrated, and then recrystallized using ethanol to obtain an epoxy group-containing cinnamic acid derivative (a-2-5).

The compounds corresponding to the abbreviations in Table 1 are shown below.

Synthesis Example of Polymer Composition (C)

The following describes Synthesis Example C-1-1 to Synthesis Example C-1-10 and Synthesis Example C-2-1 to Synthesis Example C-2-3 of the polymer composition (C):

Synthesis Example C-1-1

A 500 ml four-necked conical flask was provided with a nitrogen inlet, a stirrer, a condenser tube, and a thermometer, and nitrogen was introduced. Then, in a four-necked conical flask, 5.41 g (0.05 mol) of p-diaminobenzene (abbreviated as (c-2-1)) and 80 g of N-methyl-2-pyrrolidone (N- methyl-2-pyrrolidone (abbreviated as NMP), and stirred at room temperature until dissolved. Next, 10.91 g (0.05 mol) of pyromellitic dianhydride (abbreviated as c-1-1) and 20 g of NMP were added and reacted at room temperature for 2 hours. After the reaction is completed, the reaction solution is poured into 1500 ml of water to precipitate a polymer. Then, the obtained polymer was filtered, repeatedly washed with methanol and filtered three times, put into a vacuum oven, and dried at a temperature of 60 ° C. to obtain a polymer composition (C-1-1).

Synthesis Example C-1-2 to Synthesis Example C-1-8

Synthesis Example C-1-2 to Synthesis Example C-1-8 The same procedures as in Synthesis Example C-1-1 were used to prepare a polymer composition (C-1-2) to a polymer composition (C-1- 8), and the difference lies in: changing the type of monomer and its use amount (as shown in Table 2).

Synthesis Example C-2-1

A 500 ml four-necked Erlenmeyer flask was equipped with a nitrogen inlet and stirred Heater, condenser and thermometer, and introduce nitrogen. Then, in a four-necked Erlenmeyer flask, 4.86 g (0.045 mole) of p-diaminobenzene (abbreviated as (c-2-1)) and 2.6 g (0.005 mole) of HCDA (abbreviated as (c- 2-4)) and 80 g of N-methyl-2-pyrrolidonc (NMP), and stirred at room temperature until dissolved. Next, 10.91 g (0.05 mol) of pyromellitic dianhydride (abbreviated as c-1-1) and 20 g of NMP were added. After reacting at room temperature for 6 hours, 97 g of NMP, 2.55 g of acetic anhydride, and 19.75 g of pyridine were added, the temperature was raised to 60 ° C., and stirring was continued for 2 hours to carry out the imidization reaction. After the reaction is completed, the reaction solution is poured into 1500 ml of water to precipitate a polymer. Then, the obtained polymer was filtered, repeatedly washed with methanol and filtered three times, put into a vacuum oven, and dried at a temperature of 60 ° C. to obtain a polymer composition (C-2-1).

Synthesis Example C-2-2 to Synthesis Example C-2-3

Synthesis Example C-2-2 to Synthesis Example C-2-3 In the same procedure as Synthesis Example C-2-1, the polymerization composition (C-2-2) to the polymerization composition (C-2- 3), and its difference lies in: changing the type of monomer and its use amount (as shown in Table 2).

The compounds corresponding to the abbreviations in Table 2 are shown below.

Examples and comparative examples of liquid crystal alignment agents, liquid crystal alignment films, and liquid crystal display elements

Examples 1 to 20 and Comparative Examples 1 to 9 of the liquid crystal alignment agent, the liquid crystal alignment film, and the liquid crystal display element will be described below:

a. Liquid crystal alignment agent

Weigh 100 parts by weight of photo-alignable polysiloxane (A-1) and 800 parts by weight of N-methyl-2-pyrrolidone (abbreviated as B-1), and continue stirring at room temperature with a stirring device Until dissolved, the liquid crystal alignment agent of Example 1 can be formed.

b. Liquid crystal alignment film and liquid crystal display element

The liquid crystal alignment agent is spin-coated on a glass substrate having a conductive film made of ITO, and then pre-baked on a hot plate at a temperature of 70 ° C for 3 minutes, and in a circulating oven at a temperature of After baking at 220 ° C for 20 minutes, a coating film can be obtained.

Using a Hg-Xe lamp and a Glan-Taylor prism, the surface of the coating film was irradiated with polarized ultraviolet rays containing 313 nm bright lines for 50 seconds from a direction inclined from the substrate normal by 40 °, thereby imparting liquid crystal. The alignment energy can be used to make a liquid crystal alignment film. At this time, the illuminance of the illuminated surface at a wavelength of 313 nm was 2 mW / cm ² . The same operation was repeated to produce two (one pair) substrates having a liquid crystal alignment film.

Next, by screen printing, the outer periphery of the surface on which the liquid crystal alignment film is formed of the one pair of substrates is coated with an epoxy resin adhesive containing alumina balls having a diameter of 5.5 μm, so that the liquid crystal alignment of each substrate is The film surface is opposite and polarized UV light The substrates were bonded in an anti-parallel irradiation direction, and a pressure of 10 kg was applied by a hot press to perform hot-press bonding at 150 ° C.

Thereafter, liquid crystal is injected from the liquid crystal injection port, and the liquid crystal injection port is sealed with an epoxy-based adhesive. In order to eliminate the flow alignment during the liquid crystal injection, it is heated to 150 ° C and then slowly cooled to room temperature. Finally, the polarizing plates are bonded to the outer surfaces of the substrate so that their polarizing directions are perpendicular to each other and the polarizing direction of the ultraviolet rays of the liquid crystal alignment film is 45 °, so that the liquid crystal display element of Example 1 can be obtained. The liquid crystal display element of Example 1 was evaluated by each evaluation method described later, and the results are shown in Table 3.

Examples 2 to 20

The liquid crystal alignment agent, the liquid crystal alignment film, and the liquid crystal display element of Examples 2 to 20 were prepared by the same steps as in Example 1, and the difference was that the type of the component and the amount of use were changed, as shown in Table 3. Show. The liquid crystal display elements prepared in Examples 2 to 20 were evaluated in an evaluation method described later, and the results are shown in Table 3.

Comparative Examples 1 to 9

The liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element of Comparative Example 1 to Comparative Example 9 were separately prepared in the same steps as in Example 1, except that the type of the component and the amount of use were changed, as shown in Table 4. . The liquid crystal display elements prepared in Comparative Examples 1 to 9 were evaluated in the evaluation method described later, and the results were evaluated. As shown in Table 4.

The compounds corresponding to the abbreviations in Tables 3 and 4 are shown below.

D-2 N, N-Glycidyl-p-glycidoxyaniline

Evaluation method a. Light stability

For the liquid crystal display device manufactured as described above, a voltage of 1 V was applied at 70 ° C with an application time of 60 microseconds and a span of 16.67 milliseconds, and then the voltage retention rate after 16.67 milliseconds was removed was measured. Retention rate VHR _B1 .

The liquid crystal display element after the initial voltage holding ratio measurement was irradiated with ultraviolet light of 10,000 J / m ² using a metal halide lamp having an illuminance of 800 W / m ² , and then allowed to stand at room temperature and naturally cooled to room temperature. Next, the voltage holding ratio was measured again in the same manner as described above, and this value was taken as the voltage holding ratio VHR _A1 after irradiation. The change rate of the voltage holding rate at this time is calculated by the following formula (1),

The evaluation criteria of light stability are shown below.

◎: Change rate ≦ 5%

○: 5% <change rate ≦ 10%

△: 10% <change rate ≦ 20%

×: Change rate> 20%

b. Brightness stability

In order to measure the luminance before the stress is applied, the luminance (brightness value L1) is measured with a photometer with a voltage of AC1V applied to the liquid crystal cell. Next, a stress of 5 VAC and 0.5 VDC was applied to the liquid crystal cells for 6 hours. After the stress was applied, the luminance (luminance value L2) was measured with a photometer in a state where a voltage of AC1V was applied to the liquid crystal cell.

The following formula (2) is used to calculate the luminance change rate.

Luminance change rate = (L2-L1) / L1 × 100 Equation (2)

The evaluation criteria for brightness stability are shown below.

◎: Brightness change rate ≦ 20%

○: 20% <brightness change rate ≦ 30%

△: 30% <brightness change rate ≦ 40%

×: Brightness change rate> 40%

Evaluation results

As can be seen from Tables 3 and 4, when the monomer component of the photo-alignable polysiloxane (A) was synthesized, the polysiloxane (a-1) containing an acid anhydride group was not included (Comparative Example 1 to Comparative In Example 3), the liquid crystal alignment agent had poor light stability and poor brightness stability.

In addition, when an epoxy group-containing cinnamic acid derivative (a-2) (Comparative Example 1 to Comparative Example 5) is not included in the monomer component of the photo-alignable polysiloxane (A), the liquid crystal alignment The light stability of the agent is not good, and the brightness stability is poor.

In addition, when the monomer component of the polysiloxane (A) is synthesized, the amount of the silane monomer (a-1-1) used is 0.3 mol to 1.0 mol (Examples 1 to 5, 8 to 20) In this case, the light stabilizer of the liquid crystal alignment agent is better. From this, it can be seen that when the amount of the silane monomer (a-1-1) used is 0.3 mol to 1.0 mol, the light stability of the liquid crystal display element can be further improved.

When the liquid crystal alignment agent further contains a polymer composition (C) (Examples 8 to 20), the brightness stability of the liquid crystal alignment agent is better. From this, it can be seen that when the polymer composition (C) is contained in the liquid crystal alignment agent, the brightness stability of the liquid crystal display element can be further improved.

In summary, the liquid crystal alignment agent of the present invention includes a photo-alignment polysiloxane formed by reacting an acid anhydride group-containing polysiloxane with an epoxy group-containing cinnamic acid derivative. Therefore, the liquid crystal alignment agent is applied. In the case of a liquid crystal alignment film, the liquid crystal alignment film has characteristics of good light stability and good brightness stability, and is therefore suitable for a liquid crystal display element.

Although the present invention has been disclosed as above with the examples, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field will not depart from the present invention. Within the spirit and scope, some modifications and retouching can be made. Therefore, the scope of protection of the present invention shall be determined by the scope of the attached patent application.

Claims (10)

A liquid crystal alignment agent, comprising: photo-alignable polysiloxane (A); and a solvent (B), wherein the photo-alignable polysiloxane (A) is an acid anhydride-containing polysiloxane (a) -1) It is obtained by reacting with an epoxy-containing cinnamic acid derivative (a-2). The liquid crystal alignment agent according to item 1 of the scope of patent application, wherein the polysiloxane (a-1) containing an acid anhydride group comprises a copolymer obtained by hydrolyzing and partially condensing the first mixture, The first mixture includes a silane monomer (a-1-1) represented by formula (1-1); Si (R ^a ) _w (OR ^b ) _4-w formula (1-1) formula (1-1) ), R ^a each independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 15 carbon atoms, an alkyl group containing an acid anhydride group, and at least one R ^a is an alkyl group containing an acid anhydride group; when R ^a is plural, each may be the same or different; R ^b each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and 醯 having 1 to 6 carbon atoms Group or aryl group having 6 to 15 carbon atoms; when R ^b is plural, each may be the same or different; w represents an integer of 1 to 3; The liquid crystal alignment agent according to item 1 of the scope of patent application, wherein the epoxy group-containing cinnamic acid derivative (a-2) is a compound represented by formula (2-1) to formula (2-2) At least one of the groups formed, In the formula (2-1), W ¹ represents an alkyl group having 1 to 40 carbon atoms or a monovalent alicyclic organic group having 3 to 40 carbon atoms, wherein a part or all of the hydrogen atoms of the alkyl group May be substituted by a fluorine atom; W ² represents a single bond, an oxygen atom, -COO- or -OCO-; W ³ represents a divalent aromatic group, a divalent alicyclic group; W ⁴ represents a single bond, an oxygen atom, -COO- or -OCO-; W ⁵ represents a single bond,-(CH ₂ ) _h -COO-,-(CH ₂ ) _i -O- or a divalent aromatic group, said divalent aromatic group, It may have -COO- substitution, wherein h and i each independently represent an integer of 1 to 10; W ⁶ represents an epoxy group; W ⁷ represents a fluorine atom or a cyano group; a represents an integer of 0 to 3; b represents 0 to 4 An integer of 0; a + b ≦ 5; t represents an integer of 0 to 1; in formula (2-2), W ⁸ represents an alkyl group having 1 to 40 carbon atoms or a monovalent lipid having 3 to 40 carbon atoms A cyclic organic group in which a part or all of the hydrogen atoms of the alkyl group may be substituted with a fluorine atom; W ⁹ represents an oxygen atom or a divalent aromatic group; W ¹⁰ represents an oxygen atom, -COO- or -OCO- ; W ¹¹ represents a divalent aromatic group and a divalent alicyclic group; W ¹² represents an oxygen atom, -COO-, -OCO -(CH ₂ ) _e -COO- or -OCO- (CH ₂ ) _g -O-, wherein e and g each independently represent an integer of 1 to 10; W ¹³ represents an epoxy group; W ¹⁴ represents a fluorine atom or cyanide Base; c represents an integer from 0 to 3; d represents an integer from 0 to 4; 0 ≦ c + d ≦ 5. The liquid crystal alignment agent according to item 2 of the scope of patent application, wherein the amount of the silane monomer (a-1-1) used is based on the total amount of the silane monomer in the first mixture being 1 mole. It is 0.3 mol to 1.0 mol. The liquid crystal alignment agent according to item 1 of the patent application scope, wherein the used amount of the photo-alignable polysiloxane (A) is 100 parts by weight, and the used amount of the solvent (B) is 800 parts by weight to 4000 Parts by weight. The liquid crystal alignment agent according to item 1 of the scope of patent application, further comprising a polymer composition (C) obtained by reacting a second mixture including a tetracarboxylic acid Acid dianhydride component (c-1) and diamine component (c-2). The liquid crystal alignment agent according to item 6 of the patent application scope, wherein the polymerization is based on a total amount of 100 parts by weight of the photo-alignable polysiloxane (A) and the polymerization composition (C), and the polymerization The composition (C) is used in an amount of 1 to 99 parts by weight. The liquid crystal alignment agent according to item 6 of the patent application scope, wherein the solvent is 100 parts by weight based on a total amount of the photo-alignable polysiloxane (A) and the polymer composition (C), and the solvent (B) is used in an amount of 800 to 4,000 parts by weight. A liquid crystal alignment film is formed by the liquid crystal alignment agent according to any one of the first to eighth patent applications. A liquid crystal display element includes the liquid crystal alignment film according to item 9 of the scope of patent application.