JP5459228B2 - Liquid crystal alignment agent for inkjet coating, liquid crystal alignment film, and liquid crystal display element - Google Patents

Description

  The present invention mainly includes a polysiloxane, particularly polysiloxane obtained by polycondensation of alkoxysilane, and a liquid crystal aligning agent capable of forming a uniform film by inkjet coating, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and The present invention relates to a liquid crystal display element having the liquid crystal alignment film.

It is generally known that a liquid crystal display element has a structure in which two substrates each having a liquid crystal alignment film provided on a transparent electrode are arranged to face each other and a liquid crystal material is filled in a gap therebetween.
Recently, a metal halide lamp with high irradiation intensity is used as a light source for a liquid crystal projector for business use and home theater (a rear pro TV referred to as a third thin TV). Therefore, not only high heat resistance but also high light resistance is required as a characteristic of the liquid crystal alignment film.

Commonly used liquid crystal alignment film materials are mainly composed of polyamic acid or polyimide, but inorganic liquid crystal alignment films have also been proposed. For example, a liquid crystal alignment film is formed by vapor deposition (see, for example, Patent Document 1).
In addition, an alignment agent composition containing a reaction product of tetraalkoxysilane, trialkoxysilane, alcohol, and oxalic acid is proposed as a coating-type inorganic liquid crystal alignment film, and an electrode substrate for a liquid crystal display element is proposed. It has been reported that a liquid crystal alignment film having excellent vertical alignment properties, heat resistance and uniformity is formed (see, for example, Patent Document 2).
Furthermore, a liquid crystal aligning agent composition containing a reaction product of tetraalkoxysilane, trialkoxysilane and water, and a glycol ether solvent has been proposed to prevent display defects and good afterimage characteristics even after long-time driving. In addition, it has been reported that a liquid crystal alignment film is formed without decreasing the ability to align liquid crystals and with little decrease in voltage holding ratio against light and heat (see, for example, Patent Document 3).

In general, examples of the method for forming a liquid crystal alignment film include spin coating, dip coating, flexographic printing, and the like, but actually, flexographic printing is often used. However, in flexographic printing, the printing plate must be exchanged according to the size of the substrate for forming the liquid crystal alignment film, and provisional film formation must be performed to stabilize the film formation process. It is a problem.
For this reason, an inkjet coating method has attracted attention as a new coating method that does not use a printing plate. The ink jet coating method is a method in which fine droplets are dropped on a substrate and the film is formed by wetting and spreading the liquid. Not only the printing plate is not used, but also a printing pattern can be freely set. The manufacturing process can be simplified. Moreover, there is an advantage that the waste of the coating liquid is reduced by eliminating the need for temporary film formation. For this reason, cost reduction of liquid crystal panels and improvement in production efficiency are expected.
Under such circumstances, it is desired to introduce a process for forming a liquid crystal alignment film by inkjet coating together with a demand for an inorganic liquid crystal alignment film having excellent heat resistance and light resistance. There is a need for a liquid crystal aligning agent.

JP 2003-50397 A JP 09-281502 A JP 2005-250244 A

  An object of the present invention is to provide a silicon-based liquid crystal aligning agent that can be formed using an ink jet coating method, and to provide liquid crystal excellent in in-plane uniformity of the film and edge straightness of the film edge by ink jet coating. An alignment film is provided.

That is, the present invention has the following gist.
(1) Polysiloxane (A) having a side chain composed of a hydrocarbon group having 8 to 30 carbon atoms, substituted or unsubstituted with a fluorine atom, glycol solvent (B) having 2 to 7 carbon atoms, A liquid crystal aligning agent for inkjet coating, comprising a solvent (C) and a solvent (D).
Glycol solvent (B): 2-methyl-2,4-pentanediol.
Solvent (C): a solvent represented by the formula (A1),
K ₁ O (CH ₂ ) _w OH (A1)
(In the formula, K ₁ is an alkyl group having 1 to 4 carbon atoms, and w is an integer of 1 to 3).
Solvent (D): from at least one compound selected from the group consisting of formula (T1), formula (T2) and formula (T3), a ketone having 3 to 6 carbon atoms and an alkyl alcohol having 5 to 12 carbon atoms A solvent selected from the group consisting of:

（式中、Ｘ_１、Ｘ_３及びＸ_５は炭素数１〜４のアルキル基であり、Ｘ_２及びＸ_６は水素原子又は炭素数１〜４のアルキル基であり、Ｘ_４は炭素数１〜４のアルキル基であり、Ｐは炭素数１〜３のアルキル基であり、ｍ、ｎ、ｊ、ｋは、それぞれ独立に１〜３の整数であり、ｈは２〜３の整数である。）
（２）溶媒（Ｄ）が、式（Ｔ１）〜式（Ｔ３）で表される化合物、炭素原子を３〜６個有するケトン及び炭素数５〜１２のアルキルアルコールから選ばれる溶媒である上記（１）に記載のインクジェット塗布用液晶配向剤。
（３）ポリシロキサン（Ａ）が、式（１）で表されるアルコキシシランを含有するアルコキシシランを重縮合して得られるポリシロキサンである上記（１）又は（２）に記載のインクジェット塗布用液晶配向剤。
Ｒ_１Ｓｉ（ＯＲ_２）_３ （１）
（Ｒ_１はフッ素原子が置換された又は未置換の炭素数８〜３０の炭化水素基であり、Ｒ_２は炭素数１〜５の炭化水素基を表す。）

(In the formula, X ₁ , X ₃ and X ₅ are each an alkyl group having 1 to 4 carbon atoms, X ₂ and X ₆ are a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and X ₄ is 1 carbon atom. Is an alkyl group having ˜4, P is an alkyl group having 1 to 3 carbon atoms, m, n, j, and k are each independently an integer of 1 to 3, and h is an integer of 2 to 3 .)
(2) The above (D), wherein the solvent (D) is a solvent selected from compounds represented by formulas (T1) to (T3), ketones having 3 to 6 carbon atoms, and alkyl alcohols having 5 to 12 carbon atoms ( Liquid crystal aligning agent for inkjet coating as described in 1).
(3) For inkjet coating according to (1) or (2) above, wherein the polysiloxane (A) is a polysiloxane obtained by polycondensation of an alkoxysilane containing an alkoxysilane represented by the formula (1) Liquid crystal aligning agent.
R ₁ Si (OR ₂ ) ₃ (1)
(R ₁ represents a hydrocarbon group having 8 to 30 carbon atoms in which a fluorine atom is substituted or unsubstituted, and R ₂ represents a hydrocarbon group having 1 to 5 carbon atoms.)

(4) The polysiloxane (A) is a polysiloxane obtained by polycondensation of an alkoxysilane containing an alkoxysilane represented by the formula (1) and an alkoxysilane represented by the following formula (2). The liquid crystal aligning agent for inkjet coating as described in said (3).
(R ₃ ) _n Si (OR ₄ ) _4-n (2)
(R ₃ is a hydrogen atom, a halogen atom, a vinyl group or a hydrocarbon group having 1 to 7 carbon atoms. In this case, an arbitrary hydrogen atom of the hydrocarbon group is a glycidoxy group, a mercapto group, a methacryloxy group, an acryloxy group, It may be substituted with an isocyanate group, amino group or ureido group, and may have a hetero atom, R ₄ is a hydrocarbon group having 1 to 5 carbon atoms, and n is an integer of 0 to 3 Represents.)
(5) The polysiloxane (A) is a polysiloxane obtained by polycondensing an alkoxysilane containing an alkoxysilane represented by the formula (1) and an alkoxysilane represented by the following formula (3). The liquid crystal aligning agent for inkjet coating as described in said (3) or (4).
Si (OR ₄ ) ₄ (3)
(R ₄ represents a hydrocarbon group having 1 to 5 carbon atoms.)
(6) an inkjet coating the liquid crystal alignment agent according to any one of _{X 2} in the formula (T1) is a hydrogen atom (1) to (5).
(7) with respect to 100 parts by weight of the total amount of the values obtained by converting the silicon atoms in the SiO ₂ polysiloxane (A) has, glycol solvent (B) is 20～18,000 parts by mass, solvent (C) is 2 Liquid crystal aligning agent for inkjet coating as described in any one of said (1)-( 6 ) whose -17,500 mass parts and solvent (D) are 2-17,500 mass parts.
(8) with respect to 100 parts by weight of the total amount of the values obtained by converting the silicon atoms in the SiO ₂ polysiloxane (A) has, glycol solvent (B) is 120～17,000 parts by mass, solvent (C) is 2 The liquid crystal aligning agent for inkjet coating as described in any one of said (1)-( 7 ) whose -16,800 mass parts and solvent (D) are 2-16,800 mass parts.
( 9 ) The liquid crystal aligning agent for inkjet coating in any one of said (1)-( 8 ) whose viscosity of the said aligning agent is 1.8-18 mPa * s.
( 10 ) The liquid crystal aligning agent for inkjet application | coating in any one of said (1)-( 9 ) whose surface tension of the said aligning agent is 20-40 mN / m.
( 11 ) A liquid crystal alignment film obtained by applying the liquid crystal aligning agent for ink jet coating according to any one of the above (1) to ( 10 ) to a substrate using an ink jet apparatus and baking it.
( 12 ) A method for forming a liquid crystal alignment film obtained by applying the liquid crystal aligning agent for ink jet coating according to any one of the above (1) to ( 10 ) to a substrate using an ink jet apparatus and baking the substrate.
( 13 ) A liquid crystal display device having the liquid crystal alignment film according to ( 11 ) above.

  The liquid crystal aligning agent of this invention can form the liquid crystal aligning film excellent in the in-plane uniformity of a film | membrane, and the edge straightness of the film edge part by inkjet coating.

The present invention is described in detail below.
<Polysiloxane A>
The polysiloxane (A) used in the present invention is a side chain (hereinafter also referred to as a specific organic group) composed of a hydrocarbon group having 8 to 30 carbon atoms, preferably 8 to 22 carbon atoms substituted or unsubstituted with fluorine atoms. ).
The specific organic group has an effect of aligning the liquid crystal in one direction, but is not particularly limited as long as it has this effect. Examples thereof include an alkyl group, a fluoroalkyl group, an alkenyl group, a phenethyl group, a fluorophenylalkyl group, a styrylalkyl group, and a naphthyl group.
Among these, an alkyl group is preferable because it is easily available.
The polysiloxane (A) used in the present invention may have a plurality of specific organic groups.

  The polysiloxane (A) used in the present invention is a side chain different from the specific organic group (hereinafter, referred to as “unaffected”) as long as the effect of the present invention is not impaired for the purpose of improving adhesion with the substrate and affinity with liquid crystal molecules. It may also have a second organic group). The second organic group is an organic group having 1 to 7, preferably 1 to 6, more preferably 1 to 5 carbon atoms. The second organic group is an aliphatic hydrocarbon; a ring structure such as an aliphatic ring, an aromatic ring or a hetero ring; an unsaturated bond; a hetero atom such as an oxygen atom, a nitrogen atom or a sulfur atom; a branched structure It may be. The second organic group is a vinyl group or a hydrocarbon group having 1 to 7 carbon atoms, and any hydrogen atom of the hydrocarbon group is a glycidoxy group, a mercapto group, a methacryloxy group, an acryloxy group, an isocyanate group, an amino group. It may be substituted with a group or a ureido group, and may have a hetero atom. The polysiloxane (A) used in the present invention may have one or more second organic groups.

The method for obtaining the polysiloxane (A) described above is not particularly limited, but is generally obtained by polycondensation of alkoxysilane.
Specifically, polysiloxane (A) can be obtained by polycondensation of an alkoxysilane having an alkoxysilane represented by the following formula (1) as an essential component.
R ₁ Si (OR ₂ ) ₃ (1)
In the formula (1), R ₁ represents a specific organic group, and examples thereof are the same as those described as the specific organic group. Among these, alkoxysilanes in which R ₁ is an alkyl group are preferable because they are relatively inexpensive and easily available as commercial products. R ₂ is a hydrocarbon group having 1 to 5 carbon atoms, preferably 1 to 4 carbon atoms.

Although the specific example of the alkoxysilane represented by the said Formula (1) is given, it is not limited to this.
For example, octyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, heptadecyltrimethoxysilane, Heptadecyltriethoxysilane, octadecyltrimethoxysilane, octadecyltriethoxysilane, nonadecyltrimethoxysilane, nonadecyltriethoxysilane, undecyltriethoxysilane, undecyltrimethoxysilane, 21-docosenyltriethoxysilane, trideca Fluorooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, heptadecaful Rhodecyltriethoxysilane, isooctyltriethoxysilane, phenethyltriethoxysilane, pentafluorophenylpropyltrimethoxysilane, m-vinylphenylethyltrimethoxysilane, p-vinylphenylethyltrimethoxysilane, (1-naphthyl) triethoxysilane , (1-naphthyl) trimethoxysilane, allyloxyundecyltriethoxysilane, benzoyloxypropyltrimethoxysilane, 3- (4-methoxyphenoxy) propyltrimethoxysilane, 1-[(2-triethoxysilyl) ethyl] Cyclohexane-3,4-epoxide, 2- (diphenylphosphino) ethyltriethoxysilane, diethoxymethyloctadecylsilane, dimethoxymethyloctadecylsilane, diethoxydodecyl Chirushiran, dimethoxy dodecyl methyl silane, diethoxy decyl methyl silane, dimethoxy decyl methyl silane, diethoxy-octyl methyl silane, dimethoxy octyl methyl silane, ethoxy dimethyl octadecyl silane, methoxy dimethyloctadecylsilane like.
Among them, octyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, heptadecyltrimethoxysilane , Heptadecyltriethoxysilane, octadecyltrimethoxysilane, octadecyltriethoxysilane, nonadecyltrimethoxysilane, nonadecyltriethoxysilane, undecyltriethoxysilane, or undecyltrimethoxysilane, diethoxymethyloctadecylsilane, diethoxy Dodecylmethylsilane is preferred.

In the present invention, a plurality of alkoxysilanes represented by the formula (1) can be used in combination.
When the use ratio of the alkoxysilane represented by the formula (1) is less than 0.1 mol% in all alkoxysilanes used for obtaining the polysiloxane (A), good liquid crystal alignment is obtained. Since it may not exist, 0.1 mol% or more is preferable. More preferably, it is 0.5 mol% or more. Moreover, when it exceeds 30 mol%, since the liquid crystal aligning film formed may not fully harden | cure, 30 mol% or less is preferable. More preferably, it is 22 mol% or less. More preferably, it is 15 mol% or less.
Moreover, in this invention, it is preferable that it is the polysiloxane obtained by polycondensing the alkoxysilane containing the alkoxysilane represented by Formula (1) and the alkoxysilane represented by following formula (2). .
(R ₃ ) _n Si (OR ₄ ) _4-n (2)

R ₃ is a hydrogen atom, a halogen atom, a vinyl group or a hydrocarbon group having 1 to 7 carbon atoms, preferably a hydrogen atom or a hydrocarbon group having 1 to 7 carbon atoms. Any hydrogen atom of the hydrocarbon group may be substituted with a glycidoxy group, mercapto group, methacryloxy group, acryloxy group, isocyanate group, amino group or ureido group, and may have a hetero atom. Good. R ⁴ is a hydrocarbon group having 1 to 5 carbon atoms, preferably 1 to ⁴ carbon atoms, more preferably 1 to 3 carbon atoms, and n represents an integer of 0 to 3, preferably 0 to 2.

Moreover, when R < ₃ > of Formula (2) is a vinyl group or a hydrocarbon group, R < ₃ > represents the 2nd organic group mentioned above. Therefore, in this case, the example of R ₃ is the same as described as the second organic group above.
Examples of the alkoxysilane represented by the formula (2) include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, and butyltrimethoxysilane. Methoxysilane, butyltriethoxysilane, pentyltrimethoxysilane, pentyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2 (aminoethyl) ) 3-aminopropyltriethoxysilane, N-2 (aminoethyl) 3-aminopropyltrimethoxysilane, 3- (2-aminoethylaminopropyl) trimethoxysilane, 3- (2-amino) Tilaminopropyl) triethoxysilane, 2-aminoethylaminomethyltrimethoxysilane, 2- (2-aminoethylthioethyl) triethoxysilane, 3-mercaptopropyltriethoxysilane, mercaptomethyltrimethoxysilane, 3-ureidopropyl Triethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, allyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acryloxy Propyltriethoxysilane, 3-isocyanatopropyltriethoxysilane, trifluoropropyltrimethoxysilane, chloropropyltriethoxysilane, bromopropyltriethoxysilane Run, 3-mercaptopropyltrimethoxysilane, and the like.
In the alkoxysilane of the formula (2), specific examples of the alkoxysilane when R ₃ is a hydrogen atom include trimethoxysilane, triethoxysilane, tripropoxysilane, tributoxysilane and the like.

In the alkoxysilane of the formula (2), an alkoxysilane in which n is 0 represents a tetraalkoxysilane of the formula (3).
Si (OR ₄ ) ₄ (3)
In the formula (3), R ₄ is a hydrocarbon group having 1 to 5 carbon atoms, preferably 1 to ₄ carbon atoms, more preferably 1 to 3 carbon atoms. The tetraalkoxysilane represented by the formula (3) is preferable for obtaining the polysiloxane (A) because it easily condenses with the alkoxysilane represented by the formula (1). Specific examples of the tetraalkoxysilane of the formula (3) include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane and the like.
When the alkoxysilane represented by the above formula (2) or formula (3) is used, one type or a plurality of types can be used as necessary.

When the alkoxysilane represented by the formula (2) or the formula (3) is used in combination, the alkoxy represented by the formula (2) or the formula (3) in all the alkoxysilanes used for obtaining the polysiloxane (A). It is preferable that the total amount of silane used is 70 to 99.7 mol%. More preferably, it is 78-99.7 mol%. More preferably, the alkoxysilane represented by Formula (2) or Formula (3) is 85-99.7 mol%.
The polysiloxane (A) used in the present invention is obtained by condensing an alkoxysilane containing an alkoxysilane represented by the above formula (1) as an essential component in an organic solvent. In that case, the alkoxysilane containing the alkoxysilane represented by Formula (1), Formula (2), and Formula (3) is preferable. Usually, the polysiloxane (A) is obtained as a solution obtained by polycondensation of such an alkoxysilane and uniformly dissolved in an organic solvent.

  The method for condensing the polysiloxane (A) used in the present invention is not particularly limited, and examples thereof include a method of hydrolyzing and condensing alkoxysilane in an alcohol or glycol solvent. At that time, the hydrolysis / condensation reaction may be either partial hydrolysis or complete hydrolysis. In the case of complete hydrolysis, theoretically 0.5 times mole of water of all alkoxy groups in the alkoxysilane may be added, but usually an excess amount of water is added more than 0.5 times mole.

In the present invention, the amount of water used in the above reaction can be appropriately selected as desired, but it is usually preferably 0.5 to 2.5 moles of all alkoxy groups in the alkoxysilane.
Usually, for the purpose of promoting hydrolysis / condensation reaction, acids such as hydrochloric acid, sulfuric acid, nitric acid, acetic acid, formic acid, succinic acid, maleic acid, fumaric acid, alkalis such as ammonia, methylamine, ethylamine, ethanolamine, triethylamine, etc. Catalysts such as hydrochloric acid, sulfuric acid, nitric acid and other metal salts are used. Furthermore, it is also common to further promote the hydrolysis / condensation reaction by heating the solution in which the alkoxysilane is dissolved. At that time, the heating temperature and the heating time can be appropriately selected as desired. Examples thereof include heating and stirring at 50 ° C. for 24 hours and heating and stirring for 1 hour under reflux.

  As another method, for example, a method of heating and polycondensing a mixture of alkoxysilane, a solvent and oxalic acid can be mentioned. Specifically, after adding succinic acid to alcohol in advance to obtain an alcohol solution of succinic acid, alkoxysilane is mixed while the solution is heated. In that case, the amount of succinic acid to be used is preferably 0.2 to 2 mol with respect to 1 mol of all alkoxy groups of the alkoxysilane. The heating in this method can be performed at a liquid temperature of 50 to 180 ° C., and preferably several tens of minutes under reflux in a container equipped with a reflux tube, for example, so that the liquid does not evaporate or volatilize. It takes about 10 hours.

When using multiple types of alkoxysilane when obtaining polysiloxane (A), alkoxysilane may be mixed as a mixture beforehand, or multiple types of alkoxysilane may be mixed sequentially.
The solvent used for polycondensation of alkoxysilane (hereinafter also referred to as polymerization solvent) is not particularly limited as long as it can dissolve alkoxysilane. Moreover, even when alkoxysilane does not melt | dissolve, what melt | dissolves as the polycondensation reaction of alkoxysilane progresses is sufficient. In general, since an alcohol is generated by a polycondensation reaction of alkoxysilane, an organic solvent having good compatibility with alcohols, glycols, glycol ethers and alcohols is used.

Specific examples of such a polymerization solvent include methanol, ethanol, propanol, butanol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 2-methyl-2,4-pentanediol, ethyl carbitol, butyl carbitol, Ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl Ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, propylene glycol dibutyl ether, N- Examples thereof include methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, γ-butyrolactone, dimethyl sulfoxide, tetramethylurea, hexamethylphosphotriamide, m-cresol and the like.
In the present invention, a plurality of the above polymerization solvents may be mixed and used.

The solution obtained after such a method generally has a concentration obtained by converting silicon atoms of all alkoxysilanes charged as raw materials into SiO ₂ (hereinafter referred to as SiO ₂ converted concentration) to 20% by mass or less. Preferably, it is 15 mass% or less. By selecting an arbitrary concentration within this concentration range, gel formation can be suppressed and a homogeneous solution can be obtained.

<Solution of polysiloxane (A)>
In the present invention, the solution obtained by the above-described method may be used as it is as the polysiloxane (A) solution. If necessary, the solution obtained by the above-described method may be concentrated or a solvent may be added. The solution of polysiloxane (A) may be diluted or replaced with another solvent.
In this case, the solvent to be used (hereinafter also referred to as an additive solvent) may be the same solvent used for polycondensation or another solvent. This solvent is not particularly limited as long as the polysiloxane (A) is uniformly dissolved, and one kind or a plurality of kinds can be arbitrarily selected and used.

Specific examples of such an additive solvent include alcohols such as methanol, ethanol, propanol, butanol, and diacetone alcohol; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; ethylene glycol, diethylene glycol, propylene glycol, 2-methyl -Glycols such as 2,4-pentanediol; ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, ethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, Diethylene glycol dimethyl ether, diethylene glycol Glycol ethers such as coal diethyl ether, diethylene glycol dipropyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether; esters such as acetic acid methyl ester, acetic acid ethyl ester, and lactate ethyl ester N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, γ-butyrolactone, dimethyl sulfoxide, tetramethylurea, hexamethylphosphotriamide, m-cresol and the like.
In the present invention, one or more of the polysiloxane (A) solutions obtained as described above may be used.

<Glycol solvent (B)>
Glycol solvent (B) used in the present invention is 2-methyl-2,4-Pentanjio Le.

Such a glycol solvent (B) may be used as all or part of a polymerization solvent or an addition solvent when polysiloxane (A) is polycondensed, and is added to polysiloxane (A) synthesized with another solvent. It may be added later.
The content of the glycol solvent (B) used in the present invention, in the liquid crystal aligning agent, relative to 100 parts by weight of the total amount of the values obtained by converting the silicon atoms in the SiO ₂ having polysiloxane (A) is glycol The solvent (B) is 20 to 18,000 parts by mass, preferably 120 to 17,000 parts by mass, and more preferably 150 to 16,000 parts by mass. When the amount is less than 20 parts by mass, good coatability may not be obtained.
Glycol solvent (B) used in the present invention can obtain an excellent film in-plane uniformity, especially.

<Solvent (C)>
The solvent (C) used in the present invention is at least one solvent selected from the group consisting of solvents represented by the formula (A1).
K ₁ O (CH ₂ ) _w OH (A1)

Wherein, K ₁ is an alkyl group having 1 to 4 carbon atoms, w is an integer of 1 to 3.
Specific examples of the solvent (C) include 2-methoxyethanol, 2-ethoxyethanol, 2-propoxyethanol, 2-butoxyethanol and the like.
The solvent (C) used in the present invention may be used as all or a part of the polymerization solvent or additive solvent for polycondensation of the polysiloxane (A). ) May be added later.
The content of the solvent (C) is preferably 2 to 17,500 parts by mass of the solvent (C) with respect to 100 parts by mass of the total amount of the silicon atoms of the polysiloxane (A) converted to SiO _2. Is 2 to 16,800 parts by mass, more preferably 2 to 16,000 parts by mass. When the amount is less than 2 parts by mass, good coatability may not be obtained.
These solvents (C) have an effect of spreading the liquid when applied, and a film having particularly excellent in-plane uniformity can be obtained.

<Solvent (D)>
The solvent (D) used in the present invention is at least one compound selected from the group consisting of the following formula (T1), formula (T2) and formula (T3), a ketone having 3 to 6 carbon atoms, and carbon. One or more solvents selected from the group consisting of several to 12 alkyl alcohols.

In the formula, X ₁ , X ₃ and X ₅ are each an alkyl group having 1 to 4 carbon atoms, X ₂ and X ₆ are a hydrogen atom or an alkyl group having 1 to ₄ carbon atoms, and X ₄ is an alkyl group having 1 to 1 carbon atoms. 4 is an alkyl group, P is an alkyl group having 1 to 3 carbon atoms, m, n, j, and k are each independently an integer of 1 to 3, and h is an integer of 2 to 3.
The solvent (D) used in the present invention is at least one selected from the group consisting of compounds of formula (T1) to formula (T3), ketones having 3 to 6 carbon atoms, and alkyl alcohols having 5 to 12 carbon atoms. A solvent is preferred.
The solvent (D) used in the present invention is, for example, a compound represented by the above formula (T1), a compound represented by the above formula (T3), a ketone having 3 to 6 carbon atoms, or 5 to 5 carbon atoms. It may be a single solvent of 12 alkyl alcohols. Moreover, the mixed solvent of the compound represented by Formula (T1) and the compound represented by Formula (T2) may be sufficient, Furthermore, the compound represented by Formula (T1), and C5-C12. A mixed solvent with an alkyl alcohol may be used.
Further, the equation _{X 2} and _{X 6} in (T1) and (T3) is preferably a hydrogen atom.

  Specific examples of the compound represented by the formula (T1) include 1-methoxy-2-propanol (propylene glycol monomethyl ether), 1-ethoxy-2-propanol (propylene glycol monoethyl ether), 1-propoxy-2-propanol ( Propylene glycol monopropyl ether), 1-butoxy-2-propanol (propylene glycol monobutyl ether), 1,2-dimethoxypropane (propylene glycol dimethyl ether), 1,2-diethoxypropane (propylene glycol diethyl ether), 1,2 -Dipropoxypropane (propylene glycol dipropyl ether) and 1,2-dibutoxypropane (propylene glycol dibutyl ether) are preferred. Of these, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-propoxy-2-propanol, or 1-butoxy-2-propanol is preferable.

Specific examples of the compound represented by the formula (T2) include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, and ethylene glycol dibutyl ether. Of these, ethylene glycol dimethyl ether or ethylene glycol dibutyl ether is preferable.
Specific examples of the compound represented by the formula (T3) include diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether and the like. . Among these, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, or diethylene glycol dibutyl ether is preferable.
Specific examples of the ketones having 3 to 6 carbon atoms in the solvent (D) include methyl ethyl ketone and methyl isobutyl ketone.
Specific examples of the alkyl alcohol having 5 to 12 carbon atoms of the solvent (D) include hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol and the like. Of these, hexanol, heptanol, octanol, nonanol, and decanol are preferable.

The solvent (D) used in the present invention may be used as all or a part of the polymerization solvent or additive solvent for polycondensation of the polysiloxane (A). ) May be added later.
The content of the solvent (D) is preferably 2 to 17,500 parts by mass of the solvent (D) with respect to 100 parts by mass of the total amount of the silicon atoms of the polysiloxane (A) converted to SiO _2. Is 2 to 16,800 parts by mass, more preferably 2 to 16,000 parts by mass. When the amount is less than 2 parts by mass, good coatability may not be obtained.
These solvents (D) can be obtained an excellent film edge straightness especially.

<Other solvents>
In the present invention, a solvent other than the glycol solvent (B), the solvent (C) and the solvent (D) may be used in combination as long as the effects of the present invention are not impaired. Specific examples of other solvents include alcohols such as methanol, ethanol, propanol, butanol, and diacetone alcohol; esters such as acetone, acetic acid methyl ester, acetic acid ethyl ester, and lactate ethyl ester; N-methyl-2-pyrrolidone N, N-dimethylformamide, N, N-dimethylacetamide, γ-butyrolactone, dimethyl sulfoxide, tetramethylurea, hexamethylphosphotriamide, m-cresol and the like.

<Other ingredients>
In the present invention, other components other than polysiloxane (A), glycol solvent (B), solvent (C), and solvent (D), for example, inorganic fine particles, metalloxane oligomers, as long as the effects of the present invention are not impaired. , A metalloxane polymer, a leveling agent, a surfactant and the like may be contained.
As the inorganic fine particles, fine particles such as silica fine particles, alumina fine particles, titania fine particles, and magnesium fluoride fine particles are preferable, and a colloid solution of these inorganic fine particles is particularly preferable. This colloidal solution may be a dispersion of inorganic fine particle powder in a dispersion medium or a commercially available colloidal solution.

In the present invention, the inclusion of inorganic fine particles makes it possible to impart the surface shape of the formed cured film and other functions. The inorganic fine particles preferably have an average particle size of 0.001 to 0.2 μm, more preferably 0.001 to 0.1 μm. When the average particle diameter of the inorganic fine particles exceeds 0.2 μm, the transparency of the cured film formed using the prepared coating liquid may be lowered.
Examples of the dispersion medium for the inorganic fine particles include water and organic solvents. As a colloidal solution, it is preferable that pH or pKa is adjusted to 1-10 from the viewpoint of the stability of the coating liquid for forming a film. More preferably, it is 2-7.

  Organic solvents used for the dispersion medium of the colloidal solution include methanol, ethanol, propanol, butanol, ethylene glycol, propylene glycol, butanediol, pentanediol, 2-methyl-2,4-pentanediol, diethylene glycol, dipropylene glycol, ethylene Alcohols such as glycol monopropyl ether; ketones such as methyl ethyl ketone and methyl isobutyl ketone; aromatic hydrocarbons such as toluene and xylene; amides such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone; ethyl acetate and butyl acetate And esters such as γ-butyrolactone; ethers such as tetrahydrofuran and 1,4-dioxane. Of these, alcohols and ketones are preferred. These organic solvents can be used alone or in admixture of two or more as a dispersion medium.

As the metalloxane oligomer or metalloxane polymer, single or composite oxide precursors such as silicon, titanium, zirconium, aluminum, tantalum, antimony, bismuth, tin, indium, and zinc are used. The metalloxane oligomer or metalloxane polymer may be a commercially available product or may be obtained from monomers such as metal alkoxides, nitrates, hydrochlorides, and carboxylates by a conventional method such as hydrolysis. .
In the present invention, by containing a metalloxane oligomer or a metalloxane polymer, it is possible to improve the refractive index of the cured film or to impart photosensitivity. When using a metalloxane oligomer or a metalloxane polymer, it may be used simultaneously with the synthesis of the polysiloxane (A) or may be added to the polysiloxane (A) later.
Specific examples of commercially available metalloxane oligomers or metalloxane polymers include siloxane oligomers or siloxanes such as methyl silicate 51, methyl silicate 53A, ethyl silicate 40, ethyl silicate 48, EMS-485, and SS-101 manufactured by Colcoat. Examples of the polymer include titanoxane oligomers such as titanium-n-butoxide tetramer manufactured by Kanto Chemical Co., Inc. You may use these individually or in mixture of 2 or more types.

Moreover, a leveling agent, surfactant, etc. can use a well-known thing, and since a commercial item is easy to acquire especially, it is preferable.
In addition, the method of mixing the above-mentioned other components with the polysiloxane (A) may be simultaneous with the solution of the polysiloxane (A) and the glycol solvent (B) or after mixing them, and is not particularly limited. .

<Preparation of liquid crystal aligning agent>
The method for preparing the liquid crystal aligning agent of the present invention is not particularly limited. The polysiloxane (A), the glycol solvent (B), the solvent (C), the solvent (D), and other components may be in a uniformly mixed state.
Usually, polysiloxane (A) is polycondensed in a solvent, and thus is obtained in a solution state. Therefore, the method of using the polymerization solution of polysiloxane (A) described above as it is is simple. When the polymerization solvent for polysiloxane (A) is glycol solvent (B), solvent (C) or solvent (D), glycol solvent (B), solvent (C) or solvent (D) is not added later May be. When the solution of the polysiloxane (A) does not contain the glycol solvent (B), the solvent (C) or the solvent (D), the glycol solvent (B) or the solvent (C) is used when preparing the liquid crystal aligning agent. ) Or solvent (D) can be added.
In preparing the liquid crystal aligning agent, SiO ₂ concentration in terms of liquid crystal alignment agent is preferably 0.5 to 15 mass%, more preferably 1-6 wt%. Within such a SiO ₂ equivalent concentration range, it is easy to obtain a desired film thickness by a single application, and it is easy to obtain a sufficient pot life of the solution.
At this time, the solvent used for adjusting the SiO2 equivalent concentration may be at least one solvent selected from the group consisting of a polymerization solvent for polysiloxane (A), an additive solvent, and a glycol solvent (B).

  The liquid crystal aligning agent of this invention can form the liquid crystal aligning film excellent in the in-plane uniformity of a film | membrane, and the edge straightness of a film | membrane edge part by inkjet coating.

<Liquid crystal alignment film and method for forming the same>
Examples of the application method of the liquid crystal aligning agent for forming the liquid crystal alignment film include spin coating, printing, ink jet coating, spraying, roll coating, and the like. The coating method has attracted attention.
The ink jet coating method is a method in which fine droplets are dropped on a substrate and a film is formed by wetting and spreading of the liquid.
The liquid crystal aligning agent of this invention has favorable applicability | paintability, and when an inkjet coating method is used, it can apply | coat stably and a liquid crystal aligning film can be obtained by this coating method. Moreover, it can be set as a cured film by baking after application | coating.
In order to form a film more uniformly by using an ink jet coating method, it is necessary to stably discharge a liquid from an ink jet nozzle. One of the factors for stably discharging the liquid is the liquid viscosity. The viscosity of the preferred liquid of the liquid crystal aligning agent varies depending on the ink jet coating apparatus used, but is approximately 1.8 to 18 mPa · s (measurement temperature) with an E-type viscometer (for example, a viscometer TV-20 manufactured by Toki Sangyo Co., Ltd.) 25 ° C.) is preferred. More preferably, it is 3 to 15 mPa · s.

In addition, the surface tension of the liquid greatly influences one of the causes of the spread of the dropped droplet. The surface tension of the liquid crystal aligning agent varies depending on the type of material used, but is approximately 20 to 40 mN / in the hanging drop method (for example, AUTO DISPENSER AD-3, manufactured by Kyowa Interface Science Co., Ltd., measuring temperature 25 ° C.). A range of m is preferred.
The liquid crystal aligning agent of the present invention preferably has a viscosity of 1.8 to 18 mPa · s (measurement temperature 25 ° C.) and a surface tension of 20 to 40 mN / m (measurement temperature 25 ° C.).
The drying process after applying the liquid crystal aligning agent is not necessarily required, but if the time from application to baking is not constant for each substrate, or if baking is not performed immediately after application, a drying process is included. Is preferred. The drying is not particularly limited as long as the solvent is removed to such an extent that the shape of the coating film is not deformed by transporting the substrate or the like. For example, a method of drying on a hot plate at a temperature of 40 to 150 ° C., preferably 60 to 100 ° C. for 0.5 to 30 minutes, preferably 1 to 5 minutes can be mentioned.

The coating film formed by applying the liquid crystal aligning agent by the above method can be baked to obtain a cured film. In that case, although baking temperature can be performed at 100-350 degreeC arbitrary temperatures, Preferably it is 140-300 degreeC, More preferably, it is 150-230 degreeC, More preferably, it is 160-220 degreeC.
The polysiloxane (A) in the liquid crystal alignment film undergoes polycondensation in the firing step. However, in the present invention, it is not necessary to completely polycondense unless the effects of the present invention are impaired. However, firing is preferably performed at a temperature higher by 10 ° C. or more than the heat treatment temperature required for the liquid crystal cell production process, such as curing of the sealant.
The thickness of the cured film can be selected as necessary. When the thickness of the cured film is 5 nm or more, it is preferable because the reliability of the liquid crystal display element is easily obtained. More preferably, it is 10 nm or more. Moreover, the case of 300 nm or less is preferable because the power consumption of the liquid crystal display element does not become extremely large. More preferably, it is 150 nm or less.
Such a cured film can be used as a liquid crystal alignment film as it is. However, the cured film is rubbed, irradiated with polarized light, light of a specific wavelength, etc. An alignment film can also be used.
Since the liquid crystal alignment film of the present invention formed by the above method exhibits high water repellency, good liquid crystal vertical alignment can be obtained.

<Liquid crystal display element>
The liquid crystal display element of the present invention can be obtained by forming a liquid crystal alignment film on a substrate by the method described above and then manufacturing a liquid crystal cell by a known method.
As an example of manufacturing a liquid crystal cell, a method is generally employed in which a pair of substrates on which a liquid crystal alignment film is formed are fixed with a sealant with a spacer interposed therebetween, and liquid crystal is injected and sealed. In this case, the size of the spacer used is 1 to 30 μm, preferably 2 to 10 μm. The method for injecting the liquid crystal is not particularly limited, and examples thereof include a vacuum method for injecting liquid crystal after reducing the pressure inside the manufactured liquid crystal cell, and a dropping method for sealing after dropping the liquid crystal.
The substrate used for the liquid crystal display element is not particularly limited as long as it is a highly transparent substrate, but is usually a substrate in which a transparent electrode for driving liquid crystal is formed on the substrate. Specific examples include glass plates; polycarbonate, poly (meth) acrylate, polyethersulfone, polyarylate, polyurethane, polysulfone, polyether, polyetherketone, trimethylpentene, polyolefin, polyethylene terephthalate, (meth) acrylonitrile, triacetyl. Examples thereof include a substrate in which a transparent electrode is formed on a plastic plate such as cellulose, diacetyl cellulose, and acetate butyrate cellulose.

In a high-performance element such as a TFT type liquid crystal display element, an element in which an element such as a transistor is formed between an electrode for driving liquid crystal and a substrate is used.
In the case of a transmissive liquid crystal display element, it is common to use a substrate as described above. However, in a reflective liquid crystal display element, if only one substrate is used, an opaque substrate such as a silicon wafer may be used. Is possible. At that time, a material such as aluminum that reflects light may be used for the electrode formed on the substrate.

Hereinafter, the present invention will be described in more detail by way of examples. However, the present invention is not construed as being limited thereto. Abbreviations in the compounds used in the examples are as follows.
TEOS: tetraethoxysilane C18: octadecyltriethoxysilane UPS: 3-ureidopropyltriethoxysilane HG: 2-methyl-2,4-pentanediol BCS: 2-butoxyethanol PB: 1-butoxy-2-propanol 1,3 -BDO: 1,3-butanediol NMP: N-methyl-2-pyrrolidone DADE: diethylene glycol diethyl ether EDM: ethylene glycol dimethyl ether MIBK: methyl isobutyl ketone C8OH: 1-octanol

<Synthesis Example 1>
A 1 liter (L) four-necked reaction flask equipped with a thermometer and a reflux tube was charged with 22.6 g of HG, 7.5 g of BCS, 39.6 g of TEOS and 4.2 g of C18 and stirred to prepare a solution of an alkoxysilane monomer. did. To this solution, an oxalic acid solution prepared by previously mixing HG 11.3 g, BCS 3.8 g, water 10.8 g and oxalic acid 0.2 g as a catalyst was added dropwise over 30 minutes at room temperature, and stirred at room temperature for 30 minutes after completion of the addition. did. Thereafter, the mixture was heated under reflux for 1 hour and then allowed to cool to obtain a polysiloxane solution (K1) having a solid content concentration of 12% by mass as SiO2.

<Synthesis Example 2>
A 1 L four-necked reaction flask equipped with a thermometer and a reflux tube was charged with 30.2 g of HG, 39.6 g of TEOS, and 4.2 g of C18 and stirred to prepare an alkoxysilane monomer solution. To this solution, an oxalic acid solution in which 15.1 g of HG, 10.8 g of water and 0.2 g of oxalic acid as a catalyst were mixed in advance was added dropwise over 30 minutes at room temperature, and stirred at room temperature for 30 minutes after the completion of the addition. Then, after heating for 1 hour under reflux, the mixture was allowed to cool to obtain a polysiloxane solution (K2) having a solid content concentration of 12% by mass as SiO2.

<Synthesis Example 3>
A 1 L four-necked reaction flask equipped with a thermometer and a reflux tube was charged with 30.2 g of BCS, 39.6 g of TEOS, and 4.2 g of C18 and stirred to prepare an alkoxysilane monomer solution. To this solution, a oxalic acid solution in which 15.1 g of BCS, 10.8 g of water and 0.2 g of oxalic acid as a catalyst were mixed in advance was added dropwise over 30 minutes at room temperature, and stirred at room temperature for 30 minutes after the completion of the addition. Thereafter, after heating for 1 hour under reflux, the mixture was allowed to cool to obtain a polysiloxane solution (K3) having a solid content concentration of 12% by mass as SiO2.

<Synthesis Example 4>
A 1 L four-necked reaction flask equipped with a thermometer and a reflux tube was charged with 23.0 g of HG, 7.7 g of BCS, 40.4 g of TEOS, and 0.8 g of C18 and stirred to prepare an alkoxysilane monomer solution. To this solution, an oxalic acid solution in which 11.5 g of HG, 3.8 g of BCS, 10.8 g of water and 0.2 g of oxalic acid as a catalyst were mixed in advance was added dropwise over 30 minutes at room temperature, and stirred at room temperature for 30 minutes after completion of the addition. did. Then, after heating for 30 minutes under reflux, a mixed solution of 92% by weight methanol solution of UPS (1.15 g, 0.48 g of HG, 0.16 g of BCS) was added, and after heating for 30 minutes under reflux, the mixture was allowed to cool and SiO 2 A polysiloxane solution (K4) having a ₂ converted solid content concentration of 12% by mass was obtained.

<Examples 1-7, Comparative Examples 3 and 4>
The polysiloxane solution obtained in Synthesis Example 1 (K1) 50 g and each solvent were mixed so that the solvent composition shown in Table 1, SiO ₂ in terms of solid content concentration of 3 mass% of the liquid crystal alignment agent (KL1～ 7, KM3-4).

<Example 8>
50 g of the polysiloxane solution (K4) obtained in Synthesis Example 4 and each solvent were mixed so as to have the solvent composition shown in Table 2, and a liquid crystal aligning agent (KL8) having a solid content concentration of 3% by mass as SiO ₂ was mixed. Got.

<Comparative Example 1>
50 g of the polysiloxane solution (K2) obtained in Synthesis Example 2 and 150 g of HG were mixed and stirred to obtain a liquid crystal aligning agent (KM1) having a solid content concentration of 3% by mass as SiO2.

<Comparative example 2>
50 g of the polysiloxane solution (K3) obtained in Synthesis Example 3 and 150 g of BCS were mixed and stirred to obtain a liquid crystal aligning agent (KM2) having a solid content concentration in terms of SiO2 of 3% by mass.

Table 3 shows the solution viscosity and surface tension of the liquid crystal aligning agents obtained in Examples 1 to 8 and Comparative Examples 1 to 4. The solution viscosity and surface tension were measured by the following methods.
[Solution viscosity]
Using an E-type viscometer (Viscometer TV-20 manufactured by Toki Sangyo Co., Ltd.), the temperature was measured at 25 ° C.
[surface tension]
It measured using AUTO DISPENCER AD-3 made from Kyowa Interface Science.

[Inkjet coating]
Inkjet coating was performed with the following apparatus and conditions.
Device name: Hitachi Plant Technology Co., Ltd., fine pattern coating device HIS-200-1H
Coating substrate: 100 × 100 mm ITO substrate Coating area: 30 × 40 mm
Coating conditions: resolution 25 μm, stage speed 50 mm / sec, frequency 1000 Hz, pulse width 9.6 μsec, appropriate amount 42 pl, pitch width 70.5 μm, pitch length 125 μm, applied voltage: 14 to 19 V (adjusted to a film thickness of 100 nm) ), Nozzle gap 0.5 mm, leveling time 30 sec, drying temperature 60 ° C., drying time 2 min (hot plate)

[Applicability]
The obtained film was observed visually and with a microscope to confirm applicability.
Whether or not the film could be formed: A film without defects was marked with ◯, and a film with no film was marked with x.
In-plane uniformity: A film having a uniform in-plane surface was marked with ◯, and a film with irregular skin or line irregularities was marked with x.
Edge straightness: “Good” indicates that the straightness is very good, and “X” indicates that the straightness is poor.

  From Table 4, film formation is impossible in Comparative Example 1 and Comparative Example 4, and Examples 1 to 8 have better in-plane uniformity and edge straightness than Comparative Examples 2 and 3. It was found that the coating property was improved.

[Production of liquid crystal cell]
Prepare two glass substrates with transparent electrodes on which a liquid crystal alignment film is formed, spray spacers with a particle diameter of 6 μm on the liquid crystal alignment film surface of one substrate, and then apply an epoxy adhesive to the outer edge of the substrate by screen printing. After coating, the liquid crystal alignment films were laminated so as to face each other and cured after pressure bonding to produce an empty cell. MLC-6608 (trade name) manufactured by Merck was injected into this empty cell by a vacuum injection method, and then the injection hole was sealed with a UV curable resin to produce a liquid crystal cell (element). At that time, in the examples, a coating film is formed by the method described in the above [Inkjet coating], dried on a hot plate at a temperature of 80 ° C. for 5 minutes, and then baked in a hot-air circulating clean oven at a temperature of 200 ° C. for 60 minutes. A liquid crystal alignment film with a film thickness of 80 nm was used. Further, in the comparative example, a liquid crystal alignment film having a film thickness of 100 nm obtained by the same method as in the example except that the spin coating method was used instead of the ink jet coating was used.

[Liquid crystal orientation]
The liquid crystal cell produced by the above-mentioned [Production of liquid crystal cell] method was observed with a polarizing microscope, and the alignment state of the liquid crystal was confirmed. In the case where the entire liquid crystal cell shows a uniform alignment state having no defects, the mark is “◯”. The results are shown in Table 5.

[Contact angle]
Pure 3 μL was dropped on the liquid crystal alignment film, and the contact angle was measured using an automatic contact angle meter CA-Z type manufactured by Kyowa Interface Science Co., Ltd. The results are shown in Table 5.
In the examples, a coating film is formed by the method described in [Inkjet application] above, dried on a hot plate at a temperature of 80 ° C. for 5 minutes, and then baked in a hot air circulation clean oven at a temperature of 200 ° C. for 60 minutes. The obtained liquid crystal alignment film with a film thickness of 80 nm was used. In the reference example, a liquid crystal alignment film having a film thickness of 100 nm obtained by the same method as in the example except that the spin coating method was used instead of the ink jet coating was used.

  From Table 5, it was found that even a liquid crystal alignment film obtained by an ink jet coating method exhibits the same vertical alignment as a film obtained by another coating method.

Since the liquid crystal alignment film obtained by the liquid crystal aligning agent for inkjet coating of the present invention is excellent in the in-plane uniformity of the film and the straightness of the edge of the film end, the liquid crystal display element using this is reliable. It is suitably used as a liquid crystal display device having high properties.

The specification, claims, and abstracts of Japanese Patent Application No. 2008-329123 filed on Dec. 25, 2008 and Japanese Patent Application No. 2009-001359 filed on Jan. 7, 2009 are as follows. The entire contents are hereby incorporated by reference as the disclosure of the specification of the present invention.

Claims (13)

Fluorine atom is substituted or unsubstituted, polysiloxanes carbon atoms having a side chain composed of a hydrocarbon group having 8 to 30 (A), glycols following solvent (B), the following solvents (C) and a solvent ( A liquid crystal aligning agent for inkjet coating, which comprises D).
Glycol solvent (B): 2-methyl-2,4-pentanediol.
Solvent (C): a solvent represented by the formula (A1),
K ₁ O (CH ₂ ) _w OH (A1)
(In the formula, K ₁ is an alkyl group having 1 to 4 carbon atoms, and w is an integer of 1 to 3).
Solvent (D): from at least one compound selected from the group consisting of formula (T1), formula (T2) and formula (T3), a ketone having 3 to 6 carbon atoms and an alkyl alcohol having 5 to 12 carbon atoms A solvent selected from the group consisting of:

(In the formula, X ₁ , X ₃ and X ₅ are each an alkyl group having 1 to 4 carbon atoms, X ₂ and X ₆ are a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and X ₄ is 1 carbon atom. Is an alkyl group having ˜4, P is an alkyl group having 1 to 3 carbon atoms, m, n, j, and k are each independently an integer of 1 to 3, and h is an integer of 2 to 3 .)   The inkjet coating according to claim 1, wherein the solvent (D) is a solvent selected from the compounds of the formulas (T1) to (T3), ketones having 3 to 6 carbon atoms, and alkyl alcohols having 5 to 12 carbon atoms. Liquid crystal aligning agent. The liquid crystal aligning agent for inkjet coating according to claim 1 or 2, wherein the polysiloxane (A) is a polysiloxane obtained by polycondensation of an alkoxysilane containing an alkoxysilane represented by the formula (1).
R ₁ Si (OR ₂ ) ₃ (1)
(R ₁ represents a hydrocarbon group having 8 to 30 carbon atoms in which a fluorine atom is substituted or unsubstituted, and R ₂ represents a hydrocarbon group having 1 to 5 carbon atoms.) The polysiloxane (A) is a polysiloxane obtained by polycondensation of an alkoxysilane containing an alkoxysilane represented by the formula (1) and an alkoxysilane represented by the following formula (2). The liquid crystal aligning agent for inkjet application | coating of description.
(R ₃ ) _n Si (OR ₄ ) _4-n (2)
(R ₃ is a hydrogen atom, a halogen atom, a vinyl group or a hydrocarbon group having 1 to 7 carbon atoms. In this case, an arbitrary hydrogen atom of the hydrocarbon group is a glycidoxy group, a mercapto group, a methacryloxy group, an acryloxy group, It may be substituted with an isocyanate group, amino group or ureido group, and may have a hetero atom, R ₄ is a hydrocarbon group having 1 to 5 carbon atoms, and n is an integer of 0 to 3 Represents.) The polysiloxane (A) is a polysiloxane obtained by polycondensation of an alkoxysilane containing an alkoxysilane represented by the formula (1) and an alkoxysilane represented by the following formula (3). Or the liquid crystal aligning agent for inkjet coating of 4.
Si (OR ₄ ) ₄ (3)
(R ₄ represents a hydrocarbon group having 1 to 5 carbon atoms.) Inkjet coating the liquid crystal alignment agent according to any one of claims. 1 to 5 X ₂ is a hydrogen atom in the formula (T1). The glycol solvent (B) is 20 to 18,000 parts by mass and the solvent (C) is 2 to 17, with respect to 100 parts by mass of the total amount of the silicon atoms of the polysiloxane (A) converted to SiO ₂ . It is 500 mass parts and a solvent (D) is 2-17,500 mass parts, The liquid crystal aligning agent for inkjet coating as described in any one of Claims 1-6 . The glycol solvent (B) is 120 to 17,000 parts by mass and the solvent (C) is 2 to 16, with respect to 100 parts by mass of the total amount of silicon atoms of the polysiloxane (A) converted to SiO ₂ . 800 parts by mass and the solvent (D) are 2 to 16,800 parts by mass, The liquid crystal aligning agent for inkjet coating according to any one of claims 1 to 7 . Inkjet coating the liquid crystal alignment agent in any of claims 1-8 viscosity of the alignment agent is 1.8~18mPa · s. The surface tension of the aligning agent is 20 to 40 mN / m. The liquid crystal aligning agent for inkjet coating according to any one of claims 1 to 9 . The liquid crystal aligning film obtained by apply | coating the liquid crystal aligning agent for inkjet coating in any one of Claims 1-10 to a board | substrate using an inkjet apparatus, and baking. The formation method of the liquid crystal aligning film obtained by apply | coating the liquid crystal aligning agent for inkjet coating in any one of Claims 1-10 to a board | substrate using an inkjet apparatus, and baking. The liquid crystal display element which has a liquid crystal aligning film of Claim 11 .