KR20240032874A - Liquid crystal alignment agent, liquid crystal alignment film, manufacturing method of liquid crystal display device, and liquid crystal display device - Google Patents

Abstract

(상기 식 중에 있어서의 각 기호의 의미는, 명세서에 정의된 바와 같다.)Provision of a liquid crystal aligning agent, etc. that yields a liquid crystal aligning film that is excellent in resistance to AC afterimages, has low pretilt angle characteristics, and has a high voltage retention rate.
A liquid crystal aligning agent characterized by containing the following (A) component and (B) component.
(A) Component: Selected from the group consisting of a polyimide precursor having 60 mol% or more of the repeating unit represented by the following formula (1) relative to 1 mole of all repeating units in the polymer, and a polyimide that is an imidate of the polyimide precursor. At least one polymer (A).
(B) Component: A tetracarboxylic acid derivative component containing 5 mol% or more of tetracarboxylic dianhydride represented by the following formula (T _f ) based on the total tetracarboxylic acid derivative components, and a tetracarboxylic acid derivative represented by the following formula (d _n ) At least one type of polymer (B) selected from the group consisting of a polyimide precursor that is a reaction product of a diamine component containing diamine, and a polyimide that is an imidate of the polyimide precursor.

(The meaning of each symbol in the above formula is as defined in the specification.)

Description

Liquid crystal alignment agent, liquid crystal alignment film, manufacturing method of liquid crystal display device, and liquid crystal display device

The present invention relates to a liquid crystal aligning agent, a liquid crystal aligning film, a method of manufacturing a liquid crystal display element, and a liquid crystal display element.

Liquid crystal display elements used in liquid crystal televisions, navigators, smartphones, etc. usually have a liquid crystal alignment film formed within the element to control the alignment state of the liquid crystals. A liquid crystal alignment film has a function of controlling the orientation of liquid crystal molecules in a certain direction in a liquid crystal display element. For example, a liquid crystal display element has a structure in which the liquid crystal molecules which form a liquid crystal layer are clamped by the liquid crystal alignment film formed on each surface of a pair of substrates. There, the liquid crystal molecules are oriented in a certain direction by the liquid crystal aligning film, and respond by voltage application to the electrode formed between the substrate and the liquid crystal aligning film. As a result, the liquid crystal display element displays a desired image using the change in orientation due to the response of the liquid crystal molecules. As a liquid crystal alignment film, a polyimide-based liquid crystal alignment film has been mainly used so far, in which a liquid crystal alignment agent mainly composed of a polyimide precursor such as polyamic acid or a solution of soluble polyimide is applied to a glass substrate or the like and fired. there is.

Recently, with the improvement of the performance of liquid crystal display elements, in addition to applications such as large-screen, high-definition liquid crystal televisions, liquid crystal displays have been used for automotive applications (e.g., car navigation systems and meter panels), surveillance cameras, and monitors for medical cameras. devices are being used, and in response to the demand for viewing angle characteristics, transverse electric field methods such as the IPS (In Plane Switching) method and the FFS (Fringe Field Switching) method are being examined (Patent Document 1, Patent Document 2).

Publication No. WO2017-061575 Publication No. WO2020-116585

The liquid crystal alignment film used in the liquid crystal display element of the IPS drive system or FFS drive system requires an orientation regulation force for suppressing afterimages (hereinafter also referred to as AC afterimages) generated by long-term alternating current drive. In liquid crystal display devices, which are rapidly becoming higher definition, backlights with higher brightness than before are used, and specifications for display defects called "afterimages" are becoming increasingly stringent.

Patent Document 1 describes a liquid crystal alignment film for photo-alignment that is suitable for a liquid crystal display element of an IPS drive system or an FFS drive system.

Moreover, patent document 2 describes that the liquid crystal aligning film obtained from the liquid crystal aligning agent containing two types of polyamic acids has high tolerance to AC afterimage.

On the other hand, in the liquid crystal display element used for the above application, a lower pretilt angle than before is required due to the demand for viewing angle characteristics. However, as a result of examination by the present inventor, the effect of reducing the pretilt angle is not sufficient in the liquid crystal alignment film. It turned out.

In addition, one of the required characteristics of liquid crystal display devices is to exhibit a higher voltage retention rate than before by applying the above-described high-brightness backlight. If the voltage retention rate is low, display defects such as image burn-in (image burn-in of sections and lines), unevenness, or contamination that occur over time due to external stimuli such as light or temperature will occur.

In view of the above, the present invention provides a liquid crystal aligning agent, a liquid crystal aligning film thereof, and a liquid crystal aligning film, wherein a liquid crystal aligning film is obtained that is excellent in resistance to AC afterimage, has low pretilt angle characteristics, and has a high voltage retention ratio. The purpose is to provide a liquid crystal display device having a.

As a result of conducting intensive research to achieve the above-described problem, the present inventor has found that forming a liquid crystal alignment film using a liquid crystal aligning agent containing a specific polymer component is effective for achieving the above-mentioned object, and completed the present invention. reached.

The present invention is based on this knowledge and has the following as a summary.

A liquid crystal aligning agent characterized by containing the following (A) component and (B) component.

(A) Component: Selected from the group consisting of a polyimide precursor having 60 mol% or more of the repeating unit represented by the following formula (1) relative to 1 mole of all repeating units in the polymer, and a polyimide that is an imidate of the polyimide precursor. At least one polymer (A).

(B) Component: A tetracarboxylic acid derivative component containing 5 mol% or more of tetracarboxylic dianhydride represented by the following formula (T _f ) based on the total tetracarboxylic acid derivative components, and a tetracarboxylic acid derivative represented by the following formula (d _n ) At least one type of polymer (B) selected from the group consisting of a polyimide precursor that is a reaction product of a diamine component containing diamine, and a polyimide that is an imidate of the polyimide precursor.

[Formula 1]

(R ₁₁ to R ₁₄ are each independently a hydrogen atom, a halogen atom, an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkynyl group with 2 to 6 carbon atoms, or a fluorine atom containing 1 to 6 carbon atoms. represents a monovalent organic group or a phenyl group, and at least one of R ₁₁ to R ₁₄ represents a group other than a hydrogen atom as defined above. Ar ₁ and Ar _1' each represent a benzene ring, and one or more groups on the benzene ring. The hydrogen atom may be substituted with a monovalent group. L ₁ and L _1' represent a single bond, -O-, -C(=O)-, and -OC(=O)-, respectively. A has 5 carbon atoms. It represents an alkylene group of to 12 or a divalent organic group (Qa) formed by inserting either -O- or -C(=O)-O- between the carbon-carbon bonds of the alkylene group. However, L ₁ and when L _1' represents a single bond, A represents a divalent organic group (Qa), R ₁ and Z ₁ each independently represent a hydrogen atom or a monovalent organic group having 1 to 5 carbon atoms, and represent two R ₁ and Z ₁ may each be the same or different.)

[Formula 2]

(X _f is a tetravalent organic group having an alicyclic structure of 5 or more membered rings.)

[Formula 3]

(Y represents a nitrogen atom-containing heterocycle and group "*21-NR-*22" (*21, and *22 represent a bond bonding to a carbon atom constituting an aromatic ring. However, the carbon atom It does not form a ring with the nitrogen atom to which R is bonded. R represents a hydrogen atom or a monovalent organic group, and the monovalent organic group bonds to the nitrogen atom with a carbon atom other than the carbonyl carbon.) In the group consisting of the amino group represented by represents a divalent organic group having a selected nitrogen atom-containing structure.)

In addition, throughout this specification, the meanings of the following terms and symbols are as follows. The halogen atom is a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc., and is preferably a fluorine atom. * indicates a binding hand. Additionally, Boc represents a tert-butoxycarbonyl group.

According to the liquid crystal aligning agent of the present invention, a liquid crystal aligning film that is excellent in resistance to AC afterimages, has low pretilt angle characteristics, and has a high voltage retention can be obtained. Moreover, the liquid crystal display element which has the liquid crystal alignment film is excellent in viewing angle characteristics and has high display quality.

The mechanism by which the above effects of the present invention are obtained is not necessarily clear, but is roughly estimated as follows. That is, as a polymer component used for a liquid crystal aligning agent, two types of polymers (polymer (A), polymer (B)) are used, and the repeating unit constituting the one-sided polymer (polymer (A)) is a specific alkyl By having a structure derived from diamine having a lene chain length, the localization on the surface of the polymer (A) can be increased. In addition, since the diamine having the alkylene chain length has benzene rings at a constant distance from each other, it becomes possible to lower the glass transition temperature of the polymer (A). Then, when the rubbing alignment treatment is applied to the polyimide film, the stretchability of the polyimide increases and the uniformity of the pretilt angle of the liquid crystal within the film is increased, so it is thought that the pretilt angle of the liquid crystal is reduced.

1 is a schematic cross-sectional view showing an example of a transverse electric field liquid crystal display device of the present invention.
Fig. 2 is a schematic cross-sectional view showing another example of the transverse electric field liquid crystal display device of the present invention.

Below, each component contained in the liquid crystal aligning agent of this indication, and other components arbitrarily mix|blended as needed are demonstrated.

The polymer (A) and (B) contained in the liquid crystal aligning agent of this invention is a polyimide which is a polyimide precursor obtained using a tetracarboxylic acid derivative component and a diamine component, or an imidized product of this polyimide precursor. Here, the polyimide precursor is a polymer from which polyimide can be obtained by imidizing polyamic acid, polyamic acid ester, etc.

From the viewpoint of suitably obtaining the effects of the present invention, polymers (A) and (B) are more preferably polyimide precursors, and still more preferably polyamic acids. In addition, when the polymer (A) is a polyamic acid, the polymer (A) has a repeating unit represented by formula (1) in which R ₁ is a hydrogen atom. Moreover, when the polymer (A) is a polyamic acid ester, the polymer (A) has a repeating unit represented by formula (1) in which at least one of R ₁ is a group other than a hydrogen atom.

＜Polymer (A)＞

The liquid crystal aligning agent of the present invention is a polyimide precursor having 60 mol% or more of the repeating unit represented by the above formula (1) with respect to 1 mole of all repeating units in the polymer (A), and a polyimide product of the polyimide precursor. It contains at least one type of polymer (A) selected from the group consisting of mead. By containing the substituted cyclobutane skeleton, the polymer (A) has a defined conformation upon imidization. Therefore, since the obtained polymer (A) has high stereoregularity, a liquid crystal alignment film excellent in resistance to AC afterimage is obtained. In addition, since the substituted cyclobutane skeleton has a substituted structure, the probability that the polymer (A) component having high liquid crystal orientation is localized in the surface layer is increased, and it is believed that the effect of the present invention can be suitably obtained. The number of repeating units represented by formula (1) may be one, or two or more types may be used.

Examples of the monovalent organic groups for R ₁ and Z ₁ in the formula (1) include alkyl groups such as methyl, ethyl, and propyl groups; Alkenyl groups such as vinyl groups; Alkoxy groups (eg, methoxy groups, ethoxy groups), etc. can be mentioned. R ₁ and Z ₁ are preferably hydrogen atoms or methyl groups.

Specific examples of the alkyl group having 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, for R ₁₁ to R ₁₄ in formula (1) include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, and isobutyl group. group, sec-butyl group, tert-butyl group, n-pentyl group, etc. Specific examples of the alkenyl group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, for R ₁₁ to R ₁₄ include vinyl group, propenyl group, butynyl group, etc., and these may be linear. It may be branched. Specific examples of the alkynyl group having 2 to 6 carbon atoms for R ₁₁ to R ₁₄ , preferably 2 to 3 carbon atoms, include ethynyl group, 1-propynyl group, and 2-propynyl group. For R ₁₁ to R ₁₄ , the monovalent organic group containing a fluorine atom and having 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, is fluoromethyl, trifluoromethyl, pentafluoroethyl, and pentafluoro. A profiler, etc. may be mentioned.

A more preferable combination of R ₁₁ to R ₁₄ is one in which R ₁₁ and R ₁₄ have the same structure and R ₁₂ and R ₁₃ have the same structure from the viewpoint of exhibiting low pretilt angle characteristics.

Moreover, it is preferable that R ₁₁ to R ₁₄ are a hydrogen atom or a methyl group, at least one of R ₁₁ to R ₁₄ is a methyl group, and it is more preferable that at least two of R ₁₁ to R ₁₄ are a methyl group. More preferably, R ₁₁ and R ₁₄ are methyl groups and R ₁₂ and R ₁₃ are hydrogen atoms.

The alkylene group of A in the above formula (1) may be linear or branched, but is preferably a linear alkylene group.

Preferred specific examples of the group -L ₁ -AL _1' - in the above formula (1) include the following structure.

In the above formula, n is an integer of 5 to 12, more preferably an integer of 5 to 10, and still more preferably an integer of 5 to 7.

The sum of n1 and n2 is an integer of 5 to 12, more preferably an integer of 5 to 10. n1 and n2 are preferably integers of 2 to 8, and are even more preferably integers of 2 to 4.

The sum of m1, m2 and n' is an integer of 5 to 12, more preferably an integer of 5 to 10. m1 and m2 are each more preferably an integer of 1 to 4, and still more preferably an integer of 2 to 4. n' has a more preferable integer of 2 to 6, and an even more preferable integer of 2 to 4.

The binding positions of Ar ₁ and Ar _1' in the above formula (1) are preferably the 1,4-position or the 1,3-position, respectively, from the viewpoint of obtaining high liquid crystal orientation, and the 1,4-position is It is even more preferable.

As for Ar ₁ and Ar _1' , one or more hydrogen atoms on the benzene ring may each be substituted with a monovalent group, and the monovalent group includes a halogen atom and a halogen atom having 1 to 10 carbon atoms (preferably 1 to 5 carbon atoms, more preferably 1 to 5 carbon atoms). Examples include an alkyl group with 1 to 3 carbon atoms, an alkenyl group with 2 to 10 carbon atoms (preferably 2 to 5 carbon atoms, more preferably 2 to 3 carbon atoms), an alkenyl group with 1 to 10 carbon atoms (preferably 1 to 5 carbon atoms, more preferably 1 to 5 carbon atoms). Preferably an alkoxy group with 1 to 3 carbon atoms, a fluoroalkyl group with 1 to 10 carbon atoms (preferably 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms), a fluoroalkyl group with 2 to 10 carbon atoms (preferably 2 to 10 carbon atoms) 5, more preferably a fluoroalkenyl group with 2 to 3 carbon atoms, a fluoroalkoxy group with 1 to 10 carbon atoms (preferably 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms), a fluoroalkoxy group with 1 to 10 carbon atoms ( Examples include alkyloxycarbonyl groups, cyano groups, nitro groups, etc., preferably having 2 to 5 carbon atoms, more preferably 2 to 3 carbon atoms.

In the polymer (A), the ratio of the repeating units represented by the above formula (1) is preferably 60 mol% to 100 mol% with respect to 1 mole of all repeating units in the polymer (A). The ratio of the repeating unit represented by the above formula (1) is more preferably 80 mol% to 100 mol%, and still more preferably 90 mol% to 100 mol%, from the viewpoint of suitably obtaining the effects of the present invention.

When the polymer (A) is a polyamic acid, the polyamic acid is, for example, a tetracarboxylic acid derivative component containing tetracarboxylic dianhydride represented by the following formula (T ₁ ) and diamine (1) (H- NZ ₁ -Ar ₁ -L ₁ -AL _1' -Ar _1' -NZ ₁ -H (A, L ₁ , L _1' , Ar ₁ , Ar _1' , Z ₁ , Y ₁ are expressed in equation (1) and It has the same meaning.)) It can be obtained by reacting a diamine component containing. In addition, when the polymer (A) is a polyamic acid containing a repeating unit represented by the formula (2) described later, a tetracarboxylic acid derivative component containing tetracarboxylic dianhydride represented by the formula (T ₁ ) and It can be obtained by reacting a diamine component containing diamine (H-NZ ₂ -Y ₂ -NZ ₂ -H (Y ₂ and Z ₂ have the same meaning as in formula (2))).

[Formula 4]

(R ₁₁ to R ₁₄ have the same meaning as R ₁₁ to R ₁₄ in formula (1).)

The liquid crystal aligning agent of this invention may be a polyimide precursor containing a repeating unit represented by the following formula (2) other than the repeating unit represented by said formula (1), and its polyimide precursor. The repeating unit may be of one type, or may be of two or more types.

[Formula 5]

(X ₂ represents a tetravalent organic group represented by the following formula (g), and Y ₂ represents a group -Ar ₁ -L ₁ -AL _1' -Ar _1' -(Ar ₁ , Ar _1' , L ₁ , L The definition of _1' has the same meaning as in formula (1).) It represents a divalent organic group other than R ₂ and Z ₂ have the same meaning as R ₁ and Z ₁ in formula (1), respectively.)

[Formula 6]

(In formula (g), R ₁₁ to R ₁₄ have the same meaning as R ₁₁ to R ₁₄ in formula (1).)

In the above formula (2), Y ₂ is a divalent organic group, and diamine (H-NZ ₂ -Y ₂ -NZ ₂ -H (Y ₂ and Z ₂ have the same meaning as in formula (2))) A group in which two amino groups (-NZ ₂ -H) have been removed can be mentioned. As the diamine, various diamines (hereinafter also referred to as other diamines (a)) can be used depending on the characteristics of the liquid crystal aligning agent required. As the other diamine (a) mentioned above, the following can be used. As for other diamines, from the viewpoint of suitably obtaining the effects of the present invention, diamines that do not have a side chain group of 4 or more carbon atoms (however, excluding the protecting group that is removed by heating and replaced by a hydrogen atom, as described later) are preferable. do.

Diamine represented by the formula (d _n ), p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine , phenylenediamine such as 2,4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, and 2,6-diaminotoluene; 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobi Phenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 2,2'-difluoro-4,4'-diaminobiphenyl, 3,3'-difluoro-4 ,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-bis(trifluoromethyl)-4,4'- Diaminobiphenyl, 3,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'- biphenyl structure-containing diamines such as diaminobiphenyl; 1,2-bis(6-amino-2-naphthyloxy)ethane, 1,2-bis(6-amino-2-naphthyl)ethane, 6-[2-(4-aminophenoxy)ethoxy] -2-Naphthylamine, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7 -Diamines having a naphthalene structure such as diaminonaphthalene; Diamine having a photo-alignment group such as 4,4'-diaminoazobenzene or diaminotolane; Diamines having an amide bond or a urea bond, such as diamines represented by the following formulas (h-1) to (h-5); 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 1,2-bis(4-aminophenyl)ethane, 1,2- Bis(3-aminophenyl)ethane, 1,3-bis(4-aminophenyl)propane, 1,3-bis(3-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1, 4-bis(3-aminophenyl)butane, 1,5-bis(4-aminophenyl)pentane, 1,5-bis(3-aminophenyl)pentane, 1,6-bis(4-aminophenyl)hexane, 1,6-bis(3-aminophenyl)hexane, 4,4'-diaminobenzophenone, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1 , 4-bis (4-aminobenzyl) benzene, bis (4-aminophenoxy) methane, 1,2-bis (4-aminophenoxy) ethane, 1,2-bis (4-amino-2-methylphenoc) Si) ethane, 1,3-bis(4-aminophenoxy)propane, 1,4-bis(4-aminophenoxy)butane, 4-(2-(4-aminophenoxy)ethoxy)-3- Fluoroaniline, 4-amino-4'-(2-(4-aminophenoxy)ethoxy)biphenyl, diamine represented by the following formula (d _o ); 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol; 4,4'-diamino-3,3'-dihydroxybiphenyl; 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid and 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4, 4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 1,2-bis(4-aminophenyl)ethane-3-carboxylic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl- 4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid , 1,2-bis (4-aminophenyl) ethane-3,3'-dicarboxylic acid, 4,4'-diaminodiphenyl ether-3,3'-dicarboxylic acid, etc. diamines having a carboxyl group ; 4-(2-(methylamino)ethyl)aniline, 4-(2-aminoethyl)aniline, 1-(4-aminophenyl)-1,3,3-trimethyl-1H-indan-5-amine, 1- (4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-6-amine; Diamines having a photopolymerizable group at the terminal, such as 2-(2,4-diaminophenoxy)ethyl methacrylate and 2,4-diamino-N,N-diallylaniline; Cholestanyloxy-3,5-diaminobenzene, Cholestanyloxy-3,5-diaminobenzene, Cholestanyloxy-2,4-diaminobenzene, Cholestanyl 3,5-diaminobenzoate, diamines having a steroid skeleton such as 3,5-diaminobenzoic acid cholesthenyl, 3,5-diaminobenzoic acid lanostanyl, and 3,6-bis(4-aminobenzoyloxy)cholestane; Diamine represented by the following formulas (V-1) to (V-2); Groups of the following formulas (5-1) to (5-9), such as "-N(D)-" (D represents a protecting group that is desorbed by heating and replaced by a hydrogen atom, and is preferably a tert-butoxycarbonyl group. ) diamine having (however, diamine represented by the formula (d _n ) is excluded.); Diamines having siloxane bonds such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane; Metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, 4,4'- Methylenebis(cyclohexylamine), diamine in which two amino groups are bonded to a group represented by any of the formulas (Y-1) to (Y-167) described in WO2018/117239, etc.

[Formula 7]

[Formula 8]

(When there is two or more m, the two or more m may be the same or different. One or more hydrogen atoms on the benzene ring may be substituted with a monovalent group.)

Examples of equation (d _o ) will be described later.

[Formula 9]

(In Formula (V-1), m and n are integers from 0 to 3 (however, 1 ≤ m + n ≤ 4 is satisfied.), j is an integer of 0 or 1, and X ¹ is -( CH ₂ ) _a - (a is an integer from 1 to 15), -CONH-, -NHCO-, -CO-N(CH ₃ )-, -NH-, -O-, -CH ₂ O-, - CH ₂ -OCO-, -COO-, or -OCO-. R ¹ is a fluorine atom, an alkyl group containing a fluorine atom of 1 to 10 carbon atoms, an alkoxy group containing a fluorine atom of 1 to 10 carbon atoms, or an alkoxy group containing 3 to 10 carbon atoms. Represents an alkyl group, an alkoxy group having 3 to 10 carbon atoms, or an alkoxyalkyl group having 3 to 10 carbon atoms. In formula (V-2), X ² is -O-, -CH ₂ O-, -CH ₂ -OCO-, - COO-, or -OCO-, and when there are two m, n, X ¹ , and R ¹ , each independently has the above definition.)

[Formula 10]

Specific examples of the monovalent group in the formula (d _o ) include the structures exemplified for the monovalent group in the formula (d _AL ).

As diamines represented by the above formula (d _o ), from the viewpoint of lowering the pretilt angle, diamines represented by the following formulas (d _o -1) to (d _o -6), 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether and 4,4'-diaminodiphenyl ether are preferred.

[Formula 11]

In the polymer (A), the ratio of the repeating units represented by the above formula (2) is 0 to 40 mol% based on 1 mole of all repeating units in the polymer (A) from the viewpoint of suitably obtaining the effects of the present invention. It is preferable, 0 to 20 mol% is preferable, and 0 to 10 mol% is more preferable.

＜Polymer (B)＞

The diamine component used for manufacture of the polymer (B) contained in the liquid crystal aligning agent of this invention contains the diamine represented by the said formula (d _n ). By containing the diamine component, trapping of impurities that cause a decrease in voltage retention becomes possible, and the resulting liquid crystal aligning film has a high voltage retention. The diamine represented by the said formula (d _n ) may be used individually by 1 type, respectively, and may be used in combination of 2 or more types.

The diamine component used for manufacture of the said polymer (B) may be comprised from the diamine component which does not contain the diamine represented by the following formula (d _AL ).

[Formula 12]

(A is the group「*11-(CH ₂ ) _n -O-*12」(*11 represents a bond bonding to an oxygen atom or a bond bonding to a carbon atom constituting a benzene ring, *12 represents Represents a bonding hand. n is an integer from 1 to 5. Represents a divalent organic group having: Any hydrogen atom of the benzene ring bonded to the NH ₂ group may be substituted with a monovalent group.)

Examples of the nitrogen atom-containing heterocycle in the formula (d _n ) include a pyrrole ring, an imidazole ring, a pyrazole ring, a triazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, and a pyrazine ring. Indole ring, benzoimidazole ring, purine ring, quinoline ring, isoquinoline ring, naphthyridine ring, quinoxaline ring, phthalazine ring, triazine ring, carbazole ring, acridine ring, piperidine ring, pipe A razine ring, a pyrrolidine ring, a hexamethylene imine ring, etc. may be mentioned. Among these, a pyridine ring, a pyrimidine ring, a pyrazine ring, a piperidine ring, a piperazine ring, a quinoline ring, a carbazole ring, or an acridine ring is preferable.

Examples of the monovalent organic group for R in the formula (d _n ) include alkyl groups such as methyl, ethyl, and propyl groups; Alkenyl groups such as vinyl groups; Cycloalkyl groups such as cyclohexyl groups; Aryl groups such as phenyl group and methylphenyl group, and alkoxy groups (eg, methoxy group, ethoxy group), etc. are included. R is preferably a hydrogen atom or a methyl group.

Specific examples of the diamine represented by the formula (d _n ) include, for example, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, and 3,6-diamino. Carbazole, N-methyl-3,6-diaminocarbazole, 1,4-bis-(4-aminophenyl)-piperazine, 3,6-diaminoacridine, N-ethyl-3,6-dia Minocarbazole, N-phenyl-3,6-diaminocarbazole, or diamines represented by the following formulas (d _n -1) to (d _n -3) can be mentioned.

[Formula 13]

In the formula (d _n -1), m1 and m1' are each independently an integer of 1 to 2. n1 is an integer from 1 to 3. R ₁ has the same meaning as R in the amino group represented by “*21-NR-*22” above.

When a plurality of R ₁ and m1' exist, the plurality of R ₁ and m1' may be the same or different.

In the formula (d _{n -2} ) _, The structure exemplified by the nitrogen atom-containing heterocycle in can be given.

n1 is an integer of 1 to 2, and n2 is an integer that satisfies n1 + n2 = 2. L ₁ and L ₂ are each independently a single bond, -CO-, an alkylene group having 1 to 6 carbon atoms, or -O- or -CO- is inserted between or at the end of the carbon-carbon bond of the alkylene group. It is a divalent organic group that is bonded to a nitrogen atom and a carbon atom. R represents a hydrogen atom or a methyl group.

When a plurality of X ₂ , L ₂ , and R exist, the plurality of X ₂ , L ₂ , and R may be the same or different.

In the formula (d _{n -3 )} , A structure exemplified by a ring can be given.

Ar ₃ represents a divalent aromatic ring group or a divalent saturated nitrogen atom-containing heterocyclic group. Specific examples of the aromatic ring in the divalent aromatic ring group include benzene ring, naphthalene ring, anthracene ring, pyridine ring, pyrimidine ring, pyrazine ring, pyridazine ring, triazine ring, pyrrole ring, imidazole ring, and pyrazole. ring, quinoline ring, isoquinoline ring, carbazole ring, benzimidazole ring, indole ring, quinoxaline ring, and acridine ring. Specific examples of the saturated nitrogen atom-containing heterocyclic ring in the divalent saturated nitrogen atom-containing heterocyclic ring include a piperidine ring and a piperazine ring. The hydrogen atom of the aromatic ring and the saturated nitrogen atom-containing heterocycle may be substituted with a monovalent group. Specific examples of the monovalent group include the structures exemplified for the monovalent group in the above formula (d _AL ).

L ₃ is a single bond, -(CH ₂ ) _n - (n is an integer from 1 to 6), -NR'-, -(CH ₂ ) _n -NR'- (n is an integer from 1 to 6) .), -O-, -NR'-CO-, -CO-NR'-, -O-CO-, or -CO-O-, and R' is a hydrogen atom, a methyl group, or tert-butoxycarbonyl group. represents.

m3 and m3' are each independently an integer of 0 to 2, and either m3 or m3' is an integer of 1 or more.

When a plurality of Ar ₃ and L ₃ exist, the plurality of Ar ₃ and L ₃ may be the same or different.

In addition, the NH ₂ groups at both ends in the formula (d _n -3) are both bonded to the carbon atoms constituting the aromatic ring.

Preferred specific examples of the diamines represented by the above formulas (d _n -1) to (d _n -3) include diamines represented by the following formulas (Dp-1) to (Dp-6), and the following formulas (z-1) to formulas: Diamine represented by (z-14) can be mentioned.

[Formula 14]

[Formula 15]

[Formula 16]

The content of the diamine represented by the formula (d _n ) in the constituent components of the polymer (B) is preferably 20 to 95 mol% of the total diamine components used in the production of the polymer (B), and is 30 to 90 mol%. Mol% is more preferable, 40 to 90 mol% is still more preferable, and 50 to 80 mol% is even more preferable.

In addition to the above-described diamine, the diamine component used in the production of the polymer (B) contained in the liquid crystal aligning agent of the present invention is various diamines (hereinafter also referred to as other diamines (b)) depending on the characteristics of the required liquid crystal aligning agent. ) can be used.

Other diamines (b) include, for example, compounds exemplified as diamines used in the production of the polymer (A) (diamine (1), other diamines (a)). Other diamines (b), among others, do not have a side chain group of 4 or more carbon atoms (however, excluding the protective group that is detached by heating and replaced by a hydrogen atom as described above) from the viewpoint of suitably obtaining the effects of the present invention. A diamine that does not contain Other diamines (b) include, among others, from the viewpoint of suitably obtaining the effects of the present invention, the phenylenediamine, the biphenyl structure-containing diamine, 3,3'-diaminodiphenylmethane, and 3,4'- Diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 1,2-bis(4-aminophenyl)ethane, 1,2-bis(3-aminophenyl)ethane, 1,3-bis(4 -aminophenyl)propane, 1,3-bis(3-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1,4-bis(3-aminophenyl)butane, 1,5-bis (4-aminophenyl)pentane, 1,5-bis(3-aminophenyl)pentane, 1,6-bis(4-aminophenyl)hexane, 1,6-bis(3-aminophenyl)hexane, 4,4 '-Diaminobenzophenone, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(4-aminobenzyl)benzene, bis(4- Aminophenoxy)methane, 1,2-bis(4-aminophenoxy)ethane, 1,2-bis(4-amino-2-methylphenoxy)ethane, 1,3-bis(4-aminophenoxy) Propane, 1,4-bis(4-aminophenoxy)butane, 4-(2-(4-aminophenoxy)ethoxy)-3-fluoroaniline, 4-amino-4'-(2-(4 -Aminophenoxy) ethoxy) biphenyl, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, amide bond or urea bond At least one type of diamine selected from the group consisting of diamines having and 4-(2-(methylamino)ethyl)aniline is preferred. Said other diamine (b) may be used individually by 1 type, respectively, and may be used in combination of 2 or more types.

The content of the other diamine (b) in the components of the polymer (B) is preferably 5 to 80 mol%, and is 10 to 70 mol% of the total diamine components used in the production of the polymer (B). is more preferable, 10 to 60 mol% is still more preferable, and 20 to 50 mol% is still more preferable.

The tetracarboxylic acid derivative component used for manufacture of the polymer (B) contained in the liquid crystal aligning agent of this invention is tetracarboxylic dianhydride represented by the said formula (T _f ) 5 of all tetracarboxylic acid derivative components. Contains more than mol%.

Since the fall in the molecular weight of the polymer (B) is suppressed by containing the tetracarboxylic dianhydride represented by the said formula (T _f ), high liquid crystal orientation is obtained, and the liquid crystal alignment film excellent in resistance to AC afterimage is obtained. In addition, since polymer (B) has a specific tetracarboxylic dianhydride in which imidization is difficult to proceed, a polymer containing many hydrophilic groups such as carboxyl groups is obtained, and the two layers of polymer (A) and polymer (B) are separated. A liquid crystal alignment film with excellent properties is obtained. Therefore, a liquid crystal alignment film having high liquid crystal orientation and excellent resistance to AC afterimages as described above is obtained.

_{The tetravalent} organic group having an alicyclic structure with a 5-membered ring or more in A tetravalent organic group having a structure is more preferable. In addition, the alicyclic structure with a 5-membered ring or more means that, when the alicyclic structure to which the acid anhydride is bonded is a polycyclic structure, the number of atoms constituting the ring in each ring included in the polycyclic structure is 5 or more. Additionally, the alicyclic structure may be bonded to at least one of two acid anhydride groups, and may have a chain hydrocarbon structure or an aromatic ring structure together with the alicyclic structure.

Preferred specific examples of X _f include a tetravalent organic group represented by any of the following formulas (X _f -1) to (X _f -17). From the viewpoint of suitably obtaining the effects of the present invention, X _f is more preferably (X _f -1) to (X _f -4).

[Formula 17]

The total amount of tetracarboxylic acid dianhydride represented by the formula (T _f ) is more preferably 10 mol% or more of the total tetracarboxylic acid derivative components used in the production of polymer (B) from the viewpoint of obtaining the effects of the present invention. And, 20 mol% or more is more preferable.

The tetracarboxylic acid derivative component used for manufacture of the polymer (B) contained in the liquid crystal aligning agent of this invention is, in addition to the tetracarboxylic dianhydride represented by the said formula (T _f ), the required liquid crystal aligning agent. Depending on the properties, tetracarboxylic dianhydrides other than the tetracarboxylic dianhydride represented by the above formula (T _f ) (these are collectively referred to as other tetracarboxylic dianhydrides (b)) may be used. . Said other tetracarboxylic dianhydride (b) may be used individually by 1 type, or may be used in combination of 2 or more types.

Specific examples of other tetracarboxylic dianhydrides (b) include alicyclic tetracarboxylic dianhydrides other than tetracarboxylic dianhydrides represented by the formula (T _f ), and acyclic aliphatic tetracarboxylic dianhydrides. Water or aromatic tetracarboxylic dianhydride can be mentioned.

Here, the alicyclic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups, including at least one carboxyl group bonded to the alicyclic structure. However, none of these four carboxyl groups are bonded to the aromatic ring. In addition, it does not need to be composed of only an alicyclic structure, and may have a chain hydrocarbon structure or an aromatic ring structure in part.

Acyclic aliphatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups bonded to a chain hydrocarbon structure. However, it does not have to consist of only a chain hydrocarbon structure, and may have an alicyclic structure or an aromatic ring structure in part.

The aromatic tetracarboxylic dianhydride is not particularly limited as long as it is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups, including at least one carboxyl group bonded to an aromatic ring.

In the other tetracarboxylic dianhydrides (b), the acyclic aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, or aromatic tetracarboxylic dianhydride is preferably as follows: It is tetracarboxylic dianhydride represented by formula (t).

[Formula 18]

In the formula, X ₁ is a structure selected from the above formula (g) and the following formulas (X1-1) to (X1-10).

[Formula 19]

[Formula 20]

(In formulas (X1-9) to (X1-10), j and k are integers of 0 or 1, and A ₁ and A ₂ are each independently a single bond, -O-, -CO-, -COO-, represents a phenylene group, sulfonyl group, or amide bond. A plurality of A ₂ may be the same or different. * represents a bond.)

Preferred specific examples of the above formulas (X1-9) to (X1-10) include the following formulas (X _R -1) to (X _R -14). From the viewpoint of increasing the liquid crystal orientation, the above formulas (X1-9) to (X1-10) are preferably (X _R -1) to (X _R -8), (X _R -1), (X _R -4) to (X _R -6), and (X _R -8) are more preferable.

[Formula 21]

[Formula 22]

When the tetracarboxylic acid derivative component used for manufacture of the polymer (B) contained in the liquid crystal aligning agent of this invention contains other tetracarboxylic dianhydride (b), other tetracarboxylic dianhydride The content of (b) is preferably 5 to 95 mol%, more preferably 10 to 90 mol%, and 20 to 80 mol% of the total tetracarboxylic acid derivative components used in producing polymer (B). It is more preferable to be In this case, the total amount of tetracarboxylic dianhydride represented by the formula (T _f ) is preferably 5 to 95 mol%, more preferably 10 to 90 mol%, of the total tetracarboxylic acid derivative components. It is preferable, and it is more preferable that it is 20 to 80 mol%.

From the viewpoint of obtaining the effect of the present invention, the content ratio of the component (A) and the component (B) is [(A) component]/[(B) component. ] The mass ratio may be 10/90 to 90/10, 20/80 to 90/10, or 20/80 to 80/20.

<Production of polymer (A) and polymer (B)>

(Synthesis of polyamic acid)

The polyamic acid which is a polyimide precursor contained in the liquid crystal aligning agent of this invention can be manufactured by the following method, for example. In addition, tetracarboxylic acid derivatives used in the production of polymer (A) or polymer (B) include not only tetracarboxylic dianhydride, but also tetracarboxylic acid dihalide compounds and tetracarboxylic acid dialkyl esters, which are derivatives thereof. , tetracarboxylic acid dialkyl ester dihalide, etc. can also be used. Specifically, the tetracarboxylic acid derivative component containing the tetracarboxylic dianhydride and the diamine component containing the diamine are reacted in the presence of an organic solvent at preferably -20 to 150°C, more preferably 0 to 50°C. It can be synthesized by carrying out a (polycondensation) reaction at °C for preferably 0.5 to 24 hours, more preferably for 1 to 12 hours.

Specific examples of organic solvents used in the above reaction include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N -Dimethylacetamide, dimethyl sulfoxide, 1,3-dimethyl-2-imidazolidinone, etc. are mentioned. In addition, when the solvent solubility of the polymer is high, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene Glycol monoethyl ether, ethylene glycol monopropyl ether, diethylene glycol monomethyl ether, or diethylene glycol monoethyl ether can be used. These may be used in combination of two or more types.

Although the reaction of the polyamic acid can be performed at any concentration, it is preferably 1 to 50 mass%, more preferably 5 to 30 mass%. The reaction may be carried out at a high concentration in the initial stage, and then a solvent may be added. In the reaction, the ratio of the total number of moles of the diamine component and the total number of moles of the tetracarboxylic acid component is preferably 0.8 to 1.2. As in a typical polycondensation reaction, the closer the molar ratio is to 1.0, the larger the molecular weight of the polyamic acid produced.

The polyamic acid obtained by the above reaction can be recovered by precipitating the polyamic acid by injecting it into a poor solvent while stirring the reaction solution well. In addition, a purified polyamic acid powder can be obtained by performing precipitation several times, washing with a poor solvent, and drying at room temperature or by heating. The poor solvent is not particularly limited, but examples include water, methanol, ethanol, hexane, butyl cellosolve, acetone, and toluene.

(Synthesis of polyamic acid ester)

Polyamic acid ester is, for example, [I] a method of reacting the polyamic acid obtained by the above method with an esterification agent, [II] a method of reacting a tetracarboxylic acid diester and a diamine, [III] a method of reacting a tetracarboxylic acid diester. It can be obtained by known methods such as reacting a halide with a diamine.

(Synthesis of polyimide)

Additionally, polyimide can be obtained by ring-closing (imidizing) polyimide precursors such as the polyamic acid or polyamic acid ester. In addition, the imidation rate as used in this specification is the ratio of the imide group derived from tetracarboxylic dianhydride or its derivative to the total amount of the carboxyl group (or its derivative). The imidization rate does not necessarily have to be 100% and can be arbitrarily adjusted depending on the use or purpose.

[End sealant]

When synthesizing the polymers (A) and (B) in the present invention, an appropriate end-blocking agent is used along with the tetracarboxylic acid derivative component containing tetracarboxylic dianhydride and the diamine component to form an end-blocked polymer. You may synthesize the polymer.

End capping agents include, for example, acetic anhydride, maleic anhydride, nadic acid anhydride, phthalic anhydride, itaconic anhydride, cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, trimellitic anhydride, 3-(3 -trimethoxysilyl)propyl)-3,4-dihydrofuran-2,5-dione, 4,5,6,7-tetrafluoroisobenzofuran-1,3-dione, 4-ethynylphthalic anhydride Acid monoanhydride, etc.; Diester bicarbonate compounds such as di-tert-butyl bicarbonate and diallyl bicarbonate; Chlorocarbonyl compounds such as acryloyl chloride, methacryloyl chloride, and nicotinic acid chloride; Aniline, 2-aminophenol, 3-aminophenol, 4-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, cyclohexylamine, n-butylamine , monoamine compounds such as n-pentylamine, n-hexylamine, n-heptylamine, and n-octylamine; Monoisocyanate compounds such as isocyanates having unsaturated bonds such as ethyl isocyanate, phenyl isocyanate, naphthyl isocyanate, 2-acryloyloxyethyl isocyanate, and 2-methacryloyloxyethyl isocyanate; Isothiocyanate compounds, such as ethyl isothiocyanate and allyl isothiocyanate, are mentioned.

The usage ratio of the end capping agent is preferably 0.1 to 30 mole parts, and more preferably 0.1 to 20 mole parts, based on a total of 100 mole parts of the diamine component to be used.

When recovering the produced polyamic acid from the polyamic acid reaction solution, the reaction solution may be added to a solvent to cause precipitation. Solvents used for precipitation include methanol, ethanol, isopropyl alcohol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, and water. The polyamic acid precipitated by adding it to the solvent can be recovered by filtration and then dried under normal or reduced pressure, at room temperature, or by heating. Additionally, if the polymer that has been precipitated and recovered is redissolved in an organic solvent and the reprecipitated and recovered polymer is repeated 2 to 10 times, impurities in the polymer can be reduced. Examples of the solvent at this time include alcohols, ketones, hydrocarbons, etc., and it is preferable to use three or more types of solvents selected from these because the purification efficiency is further increased.

The molecular weight of the polymer (A) and polymer (B) used in the present invention is the weight measured by GPC (Gel Permeation Chromatography) method when considering the strength of the liquid crystal alignment film obtained therefrom, workability at the time of film formation, and coating film properties. The average molecular weight is preferably 5,000 to 1,000,000, more preferably 10,000 to 150,000.

The total content of the polymer contained in the liquid crystal aligning agent of the present invention can be appropriately changed depending on the setting of the thickness of the coating film to be formed, but is preferably 1% by mass or more in terms of forming a uniform and defect-free coating film. In terms of storage stability of the solution, 10% by mass or less is preferable. A particularly preferable total content of the polymer is 2 to 8 mass%.

The liquid crystal aligning agent of this invention may contain other polymers other than a polymer (A) and a polymer (B). Specific examples of other polymers include polyimide precursors other than polymer (A) and polymer (B), polyimide, polysiloxane, polyester, polyamide, polyurea, polyurethane, polyorganosiloxane, cellulose derivative, poly Acetal, polystyrene derivative, poly(styrene-maleic anhydride) copolymer, poly(isobutylene-maleic anhydride) copolymer, poly(vinyl ether-maleic anhydride) copolymer, poly(styrene-phenylmaleimide) derivative , and a polymer selected from the group consisting of poly(meth)acrylate. Specific examples of poly(styrene-maleic anhydride) copolymer include SMA1000, 2000, 3000 (manufactured by Cray Valley), GSM301 (manufactured by Gigi Shellac), etc., and poly(isobutylene-maleic anhydride) ) Specific examples of the copolymer include Isobam-600 (manufactured by Kuraray), and specific examples of the poly(vinyl ether-maleic anhydride) copolymer include GANTREZ AN-139 (methyl vinyl ether maleic anhydride). Acid resin, manufactured by ISP Japan Co., Ltd.) can be mentioned.

Other polymers may be used individually by 1 type, or may be used in combination of 2 or more types. The content rate of other polymers is preferably 90 parts by mass or less, more preferably 10 to 90 parts by mass, and still more preferably 20 to 80 parts by mass with respect to a total of 100 parts by mass of the polymer contained in the liquid crystal aligning agent.

It is preferable that the liquid crystal aligning agent which concerns on this invention is a liquid composition in which the said polymer (A) and polymer (B) were melt|dissolved or disperse|distributed in the organic solvent. Specifically, the organic solvent contained in the liquid crystal aligning agent is not particularly limited as long as the polyamic acid is dissolved uniformly, but may include N,N-dimethylformamide, N,N-diethylformamide, and N,N-dimethyl. Acetamide, N,N-dimethyllactamide, N,N-dimethylpropionamide, tetramethylurea, N,N-diethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrroli Don, dimethyl sulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N, N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, N-(n-propyl)-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-(n-butyl) )-2-pyrrolidone, N-(t-butyl)-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, N- Ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone (these are collectively referred to as “good solvents”), etc. Among them, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide or γ -Butyrolactone is preferred. It is preferable that content of a good solvent is 20-99 mass % of the whole solvent contained in a liquid crystal aligning agent, 20-90 mass % is more preferable, and 30-80 mass % is especially preferable.

Moreover, the organic solvent contained in a liquid crystal aligning agent is the use of the mixed solvent which used together the said solvent and the solvent (also called a poor solvent) which improves the coating property at the time of apply|coating a liquid crystal aligning agent and the surface smoothness of a coating film. desirable. Specific examples of poor solvents used in combination are given below, but they are not limited to these. 1-80 mass % of the whole solvent contained in a liquid crystal aligning agent is preferable, as for content of a poor solvent, 10-80 mass % is more preferable, and 20-70 mass % is especially preferable. The type and content of the poor solvent are appropriately selected depending on the coating device, application conditions, application environment, etc. of the liquid crystal aligning agent.

Poor solvents include, for example, diisopropyl ether, diisobutyl ether, diisobutylcarbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and ethylene glycol. Dibutyl ether, 1,2-butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether. Butyl ether, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, Ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol, 2-(2-butoxyethoxy) -1-Propanol, propylene glycol monomethyl ether acetate, propylene glycol diacetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monopropyl ether , Diethylene glycol monoethyl ether acetate, Diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, Diethylene glycol acetate, n-butyl acetate, propylene glycol monoethyl ether acetate, cyclohexyl acetate , 4-methyl-2-pentyl acetate, 3-methoxymethyl propionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-methoxypropyl propionate, butyl 3-methoxypropionate, n-butyl lactate, Isoamyl lactate, diethylene glycol monoethyl ether, diisobutyl ketone (2,6-dimethyl-4-heptanone), etc. are mentioned.

Among them, diisobutylcarbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2 -Pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone is preferred.

Preferred solvent combinations of good solvents and poor solvents include N-methyl-2-pyrrolidone, γ-butyrolactone, ethylene glycol monobutyl ether, and N-methyl-2-pyrrolidone and γ-butyrolactone. and propylene glycol monobutyl ether, N,N-dimethyllactamide and diisobutyl ketone, N-methyl-2-pyrrolidone, ethyl 3-ethoxypropionate, dipropylene glycol monomethyl ether, N-ethyl-2- Pyrrolidone, ethyl 3-ethoxypropionate, propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, ethyl 3-ethoxypropionate, diethylene glycol monopropyl ether, N-ethyl-2-pyrrolidone and 3-ethoxypropionate ethyl and diethylene glycol monopropyl ether, N,N-dimethyllactamide and ethylene glycol monobutyl ether, N,N-dimethyllactamide and propylene glycol diacetate, N-ethyl-2-pyrroli Don and Diethylene glycol diethyl ether, N-ethyl-2-pyrrolidone, Diethylene glycol monoethyl ether and butyl cellosolve acetate, N-methyl-2-pyrrolidone, Diethylene glycol monomethyl ether and butyl Cellosolve acetate, N,N-dimethyllactamide, diethylene glycol diethyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and Ethylene glycol diethyl ether, N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, N-ethyl-2-pyrrolidone and 4-Hydroxy-4-methyl-2-pentanone, propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, diisobutyl ketone, N-methyl -2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, dipropylene glycol monomethyl ether, N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone Propylene glycol monobutyl ether, N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone and propylene glycol diacetate, N-ethyl-2-pyrrolidone and 4-hydroxy-4 -Methyl-2-pentanone and dipropylene glycol dimethyl ether, γ-butyrolactone and 4-hydroxy-4-methyl-2-pentanone and diisobutyl ketone, γ-butyrolactone and 4-hydroxy-4- Methyl-2-pentanone and propylene glycol diacetate, N-methyl-2-pyrrolidone and γ-butyrolactone, propylene glycol monobutyl ether and diisobutyl ketone, N-methyl-2-pyrrolidone and γ- Butyrolactone, propylene glycol monobutyl ether, diisopropyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, diisobutylcarbinol, N-methyl-2-p. Rolidone, γ-butyrolactone, dipropylene glycol dimethyl ether, N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone, and propylene glycol mono. Butyl ether and dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone, diethylene glycol diethyl ether and dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether Propylene glycol diacetate, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, diisobutyl ketone, N-ethyl-2-pyrrolidone, γ-butyrolactone, diisobutyl ketone, N-ethyl -2-pyrrolidone, N,N-dimethyllactamide, diisobutyl ketone, N-methyl-2-pyrrolidone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, γ-butyrolactone, and ethylene. Glycol monobutyl ether acetate and dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone, ethylene glycol monobutyl ether acetate and propylene glycol dimethyl ether, N-methyl-2-pyrrolidone and 4-methyl-2 acetic acid. -Pentyl and ethylene glycol monobutyl ether, N-ethyl-2-pyrrolidone, cyclohexyl acetate and diacetone alcohol, cyclohexanone and propylene glycol monomethyl ether, cyclopentanone and propylene glycol monomethyl ether, N-methyl-2 -Pyrrolidone, cyclohexanone, propylene glycol monomethyl ether, tetramethyl urea and 4-hydroxy-4-methyl-2-pentanone, tetramethyl urea and propylene glycol diacetate, N,N-dimethylpropionamide and propylene. Glycol monobutyl ether, tetramethyl urea and propylene glycol monobutyl ether, tetramethyl urea, cyclohexanone and propylene glycol monomethyl ether, N,N-dimethylpropionamide and propylene glycol monomethyl ether, N,N-dimethylpropionamide and Ethylene glycol monobutyl ether acetate, N,N-dimethylpropionamide and ethylene glycol monobutyl ether, tetramethyl urea and propylene glycol monomethyl ether, N,N-dimethylpropionamide, cyclohexanone and diethylene glycol diethyl ether, N ,N-diethylformamide and propylene glycol monomethyl ether, N,N-diethylformamide and 4-hydroxy-4-methyl-2-pentanone, N,N-diethylformamide and propylene glycol monomethyl. Ether, etc. can be mentioned.

(additive ingredients)

The liquid crystal aligning agent of this invention may further contain components (hereinafter also referred to as additive components) other than the above-mentioned (A) component, (B) component, and organic solvent. Such additive components include, for example, a crosslinkable compound (c- 1), and at least one crosslinkable compound selected from the group consisting of a crosslinkable compound (c-2) having a polymerizable unsaturated group, a functional silane compound, a metal chelate compound, a curing accelerator, a surfactant, an antioxidant, a sensitizer, Examples include agents, preservatives, and compounds for adjusting the dielectric constant or electrical resistance of the resin film.

Preferred specific examples of the crosslinkable compounds (c-1) and (c-2) include the following compounds. As a compound having an epoxy group, 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, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6- Tetraglycidyl-2,4-hexanediol, bisphenol A-type epoxy resins such as Epicoat 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F-type epoxy resins such as Epicoat 807 (manufactured by Mitsubishi Chemical Corporation), YX-8000 ( Hydrogenated bisphenol A-type epoxy resins such as (manufactured by Mitsubishi Chemical Corporation), biphenyl skeleton-containing epoxy resins such as YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), phenol novolak-type epoxy resins such as EPPN-201 (manufactured by Nippon Chemical Company), EOCN (o, m, p-)cresol novolac type epoxy resin such as -102S (manufactured by Nippon Chemical Company), tetrakis(glycidyloxymethyl)methane, N,N,N',N'-tetraglycidyl -1,4-phenylenediamine, N,N,N',N'-tetraglycidyl-2,2'-dimethyl-4.4'-diaminobiphenyl, 2,2-bis[4-(N, Tertiary nitrogen atom is aromatic, such as N-diglycidyl-4-aminophenoxy)phenyl]propane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, etc. A compound that bonds to a carbon atom; N,N,N',N'-tetraglycidyl-1,2-diaminocyclohexane, N,N,N',N'-tetraglycidyl-1,3-diaminocyclohexane, N, N,N',N'-tetraglycidyl-1,4-diaminocyclohexane, bis(N,N-diglycidyl-4-aminocyclohexyl)methane, bis(N,N-diglycy) Dil-2-methyl-4-aminocyclohexyl)methane, bis(N,N-diglycidyl-3-methyl-4-aminocyclohexyl)methane, 1,3-bis(N,N-diglycy) dilaminomethyl)cyclohexane, 1,4-bis(N,N-diglycidylaminomethyl)cyclohexane, 1,3-bis(N,N-diglycidylaminomethyl)benzene, 1,4- Bis(N,N-diglycidylaminomethyl)benzene, 1,3,5-tris(N,N-diglycidylaminomethyl)cyclohexane, 1,3,5-tris(N,N-di Compounds in which a tertiary nitrogen atom is bonded to an aliphatic carbon atom such as glycidylaminomethyl)benzene, isocyanurate compounds such as triglycidyl isocyanurate such as TEPIC (manufactured by Nissan Chemical Co., Ltd.), Japanese Patent Publication Review Compounds described in paragraph [0037] of No. 10-338880, compounds described in WO2017/170483, etc.;

As a compound having an oxetanyl group, 1,4-bis{[(3-ethyl-3-oxetanyl)methoxy]methyl}benzene (Aaron Oxetane OXT-121 (XDO)), di[2-(3 -oxetanyl)butyl]ether (alone oxetane OXT-221 (DOX)), 1,4-bis[(3-ethyloxetan-3-yl)methoxy]benzene (HQOX), 1,3-bis [(3-ethyloxetan-3-yl)methoxy]benzene (RSOX), 1,2-bis[(3-ethyloxetan-3-yl)methoxy]benzene (CTOX), Publication No. WO2011/132751 Compounds having two or more oxetanyl groups described in paragraphs [0170] to [0175], etc.;

Compounds having an oxazoline group include compounds such as 2,2'-bis(2-oxazoline) and 2,2'-bis(4-methyl-2-oxazoline), Epochros (trade name, manufactured by Nippon Catalyst Co., Ltd.) polymers and oligomers having an oxazoline group such as, compounds described in paragraph [0115] of Japanese Patent Application Laid-Open No. 2007-286597, etc.;

A compound having a cyclocarbonate group, N,N,N',N'-tetra[(2-oxo-1,3-dioxolan-4-yl)methyl]-4,4'-diaminodiphenylmethane, N ,N',-di[(2-oxo-1,3-dioxolan-4-yl)methyl]-1,3-phenylenediamine, or paragraphs [0025] to [0030] of Publication No. WO2011/155577, Compounds described in [0032], etc.;

As a compound having a block isocyanate group, Coronate AP Stable M, Coronate 2503, 2515, 2507, 2513, 2555, Milionate MS-50 (above, manufactured by Tosoh Corporation), Takenate B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, B-882N (above, manufactured by Mitsui Chemicals), 2 described in paragraphs [0046] to [0047] of Japanese Patent Application Laid-Open No. 2014-224978 Compounds having 3 or more protected isocyanate groups, compounds having 3 or more protected isocyanate groups described in paragraphs [0119] to [0120] of WO2015/141598, etc.;

A compound having a hydroxy group and an alkoxy group, such as N,N,N',N'-tetrakis(2-hydroxyethyl)adipoamide, 2,2-bis(4-hydroxy-3,5-dihyde Roxymethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethoxymethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)-1,1 , 1,3,3,3-hexafluoropropane, WO2015/072554, a compound described in paragraph [0058] of Japanese Patent Application Laid-Open No. 2016-118753, a compound described in Japanese Patent Application Laid-Open No. 2016-200798, WO2010/074269 Compounds described in No. 1, etc.;

As a crosslinkable compound having a polymerizable unsaturated group, glycerin mono(meth)acrylate, glycerin di(meth)acrylate (1,2-, 1,3-body mixture), glycerin tris(meth)acrylate, glycerol 1, 3-diglycerolate di(meth)acrylate, pentaerythritol tri(meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate , pentaethylene glycol mono(meth)acrylate, hexaethylene glycol mono(meth)acrylate, etc.

The content of the crosslinkable compounds (c-1) and (c-2) contained in the liquid crystal aligning agent of the present invention is preferably 0.1 to 30 parts by mass with respect to a total of 100 parts by mass of the polymer components contained in the liquid crystal aligning agent. , More preferably 0.1 to 20 parts by mass, Still more preferably 1 to 10 parts by mass.

Compounds for adjusting the dielectric constant and electrical resistance of the resin film include monoamines having a nitrogen atom-containing aromatic heterocycle, such as 3-picolylamine. When using a monoamine having a nitrogen atom-containing aromatic heterocycle, its content is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, based on 100 parts by mass of the polymer component contained in the liquid crystal aligning agent. am.

Preferred specific examples of functional silane compounds include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, and 2-aminopropyltrimethoxysilane. Propyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxy Silane, 3-ureidopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxy Silane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropyl Methyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris( Examples include 3-trimethoxysilylpropyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-isocyanate propyltriethoxysilane. When using a functional silane compound, the content is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

The solid content concentration in the liquid crystal aligning agent (the ratio of the total mass of components other than the solvent of the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., and is preferably 1 to 10. The range is mass%.

The range of a particularly preferable solid content concentration varies depending on the method used when applying the liquid crystal aligning agent to the substrate. For example, when using the spin coating method, it is particularly preferable that the solid content concentration is in the range of 1.5 to 4.5 mass%. In the case of using the printing method, it is particularly preferable to set the solid content concentration in the range of 3 to 9% by mass and thereby set the solution viscosity in the range of 12 to 50 mPa·s. In the case of using the inkjet method, it is particularly preferable to set the solid content concentration in the range of 1 to 5% by mass, thereby setting the solution viscosity in the range of 3 to 15 mPa·s. The temperature when preparing the polymer composition is preferably 10 to 50°C, more preferably 20 to 30°C.

The liquid crystal aligning agent described above can be effectively applied to various technical uses, for example, a liquid crystal aligning film (a liquid crystal aligning film for a retardation film, a liquid crystal aligning film for a scanning antenna or a liquid crystal array antenna, or a transmission and scattering type liquid crystal light control element). It can also be applied to liquid crystal alignment films), protective films (e.g. protective films for color filters), spacer films, interlayer insulating films, anti-reflective films, wiring coating films, anti-static films, motor insulating films (gate insulating films in flexible displays), etc.

[Liquid crystal alignment film and liquid crystal display device]

By using the liquid crystal aligning agent, a liquid crystal aligning film can be manufactured. Moreover, the liquid crystal display element which concerns on this invention is equipped with the liquid crystal aligning film formed using the said liquid crystal aligning agent. The operation mode of the liquid crystal display device related to the present invention is not particularly limited, and examples include TN type, STN (Super Twisted Nematic) type, vertical alignment type (including VA-MVA type, VA-PVA type, etc.), It can be applied to various operation modes such as in-plane switching type (IPS type, FFS type) and optical compensation bend type (OCB type).

The liquid crystal display device of the present invention is, for example, a method comprising the following steps (1) to (4), a method including steps (1) to (2) and (4), and steps (1) to (3). ), (4-2), and (4-4), or a method including steps (1) to (3), (4-3), and (4-4).

＜Step (1): Step of applying a liquid crystal alignment agent on a substrate＞

Process (1) is a process of apply|coating the liquid crystal aligning agent of this invention on a board|substrate. Specific examples of step (1) are as follows.

The liquid crystal aligning agent of the present invention is applied to one surface of the substrate on which the patterned transparent conductive film is formed by an appropriate coating method such as, for example, a roll coater method, a spin coat method, a printing method, or an inkjet method. Here, the substrate is not particularly limited as long as it is a substrate with high transparency. In addition to a glass substrate and a silicon nitride substrate, a plastic substrate such as an acrylic substrate or polycarbonate substrate can also be used. In addition, in a reflective liquid crystal display element, an opaque material such as a silicon wafer can be used as long as it is only one side of the substrate, and a light-reflecting material such as aluminum can also be used for the electrode in this case. Additionally, when manufacturing an IPS type or FFS type liquid crystal display device, a substrate on which an electrode made of a transparent conductive film or metal film patterned in a comb pattern is formed and a counter substrate on which no electrode is formed are used.

Methods for applying a liquid crystal aligning agent to a substrate and forming a film include screen printing, offset printing, flexographic printing, an inkjet method, or a spray method. Among them, coating and film forming methods using the inkjet method can be preferably used.

<Step (2): Process of baking the applied liquid crystal aligning agent>

Process (2) is a process of baking the liquid crystal aligning agent apply|coated on a board|substrate and forming a film|membrane. Specific examples of step (2) are as follows.

After applying the liquid crystal aligning agent on the substrate in step (1), the solvent is evaporated by heating means such as a hot plate, a heat circulation oven, or an IR (infrared) oven, or the heat of the polyamic acid is evaporated. You can do mid-streaming or you can do it. The drying and baking steps after applying the liquid crystal aligning agent of the present invention can be selected at any temperature and time, and may be performed multiple times. The temperature at which the liquid crystal aligning agent is baked can be carried out, for example, at 40 to 180°C. From the viewpoint of shortening the process, it may be carried out at 40 to 150°C. The firing time is not particularly limited, but examples include 1 to 10 minutes or 1 to 5 minutes. When performing thermal imidization of a polyamic acid, you may add the process of baking in the temperature range of 150-300 degreeC, or 150-250 degreeC, for example, after the said process. The firing time is not particularly limited, but examples include a firing time of 5 to 40 minutes or 5 to 30 minutes.

Since the reliability of the liquid crystal display element may decrease if the film thickness of the film-like material after baking is too thin, it is preferably 5 to 300 nm and more preferably 10 to 200 nm.

<Step (3): Process of performing orientation treatment on the film obtained in step (2)>

Step (3) is a step of subjecting the film obtained in step (2) to an orientation treatment, as the case may be. That is, in a liquid crystal display element of a horizontal alignment type such as an IPS system or an FFS system, an orientation ability imparting treatment is performed on the coating film. On the other hand, in a liquid crystal display element of a vertical alignment type such as VA mode or PSA mode, the formed coating film can be used as a liquid crystal alignment film as is, but the coating film may be subjected to an orientation ability imparting process. Examples of the alignment treatment method for the liquid crystal alignment film include a rubbing treatment method and a photo-alignment treatment method. In the photo-alignment treatment method, radiation deflected in a certain direction is irradiated to the surface of the film-like material, and in some cases, heat treatment is preferably performed at a temperature of 150 to 250 ° C. to achieve liquid crystal orientation (also referred to as liquid crystal orientation ability) ) can be given. As radiation, ultraviolet rays or visible rays having a wavelength of 100 to 800 nm can be used. Among these, ultraviolet rays have a wavelength of preferably 100 to 400 nm, and more preferably 200 to 400 nm.

The radiation dose is preferably 1 to 10,000 mJ/cm2. Especially, 100 to 5,000 mJ/cm2 is preferable. Moreover, when irradiating radiation, in order to improve liquid crystal orientation, you may irradiate the board|substrate with the said film-like substance while heating at 50-250 degreeC. The liquid crystal alignment film manufactured in this way can stably orientate liquid crystal molecules in a certain direction.

Moreover, by the above-mentioned method, the liquid crystal alignment film irradiated with polarized radiation can be contact-treated using water or a solvent, or the liquid crystal alignment film irradiated with radiation can be heat-processed.

The solvent used in the contact treatment is not particularly limited as long as it is a solvent that dissolves decomposition products generated from film-like substances by radiation irradiation. Specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, and methyl lactate. , diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, cyclohexyl acetate, etc. The number of solvents may be one, or two or more types may be combined.

The temperature of the heat treatment for the coating film irradiated with the radiation is more preferably 50 to 300°C, and still more preferably 120 to 250°C. The heat treatment time is preferably 1 to 30 minutes, respectively.

＜Process (4): Process for manufacturing liquid crystal cells＞

Two substrates on which the liquid crystal alignment film was formed as described above are prepared, and liquid crystal is disposed between the two substrates facing each other. Specifically, the following two methods can be mentioned.

In the first method, two substrates are first arranged to face each other through a gap (cell gap) so that each liquid crystal alignment film faces each other. Next, the peripheral portions of the two substrates are bonded together using a sealant, and the liquid crystal composition is injected and filled into the cell gap defined by the substrate surface and the sealant to bring it into contact with the film surface, and then the injection hole is sealed.

The liquid crystal composition is not particularly limited, and various liquid crystal compositions containing at least one liquid crystal compound (liquid crystal molecule) and having positive or negative dielectric anisotropy can be used. In addition, hereinafter, a liquid crystal composition with a positive dielectric anisotropy is also referred to as a positive liquid crystal, and a liquid crystal composition with a negative dielectric anisotropy is also referred to as a negative liquid crystal.

The liquid crystal composition includes a fluorine atom, a hydroxy group, an amino group, a fluorine atom-containing group (e.g., trifluoromethyl group), a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an isothiocyanate group, a heterocycle, a cycloalkane, It may include a liquid crystal compound having a cycloalkene, a steroid skeleton, a benzene ring, or a naphthalene ring, and a compound having two or more rigid moieties (mesogenic skeletons) in the molecule that exhibit liquid crystallinity (for example, a rigid 2 It may also include a biphenyl structure, a bimesogenic compound in which a terphenyl structure is linked to an alkyl group, etc.). The liquid crystal composition may be a liquid crystal composition showing a nematic phase, a liquid crystal composition showing a smectic phase, or a liquid crystal composition showing a cholesteric phase.

Additionally, additives may be further added to the liquid crystal composition from the viewpoint of improving liquid crystal orientation. Such additives include photopolymerizable monomers such as compounds having a polymerizable group described below; Optically active compounds (e.g., S-811 manufactured by Merck & Co., Ltd., etc.); Antioxidants; UV absorber; pigment; Antifoaming agent; polymerization initiator; Or a polymerization inhibitor, etc. can be mentioned.

Positive liquid crystals include ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, or MLC-7081 manufactured by Merck & Co., Ltd.

Negative liquid crystals include, for example, MLC-6608, MLC-6609, MLC-6610, MLC-6882, MLC-6886, MLC-7026, MLC-7026-000, MLC-7026-100 manufactured by Merck & Co., Ltd., or MLC-7029, etc. can be mentioned.

In addition, in PSA mode, MLC-3023 manufactured by Merck & Co., Inc. can be cited as a liquid crystal containing a compound having a polymerizable group.

Additionally, the second method is a method called the ODF (One Drop Fill) method. For example, an ultraviolet light-curable sealing agent is applied to a predetermined location on one of the two substrates on which the liquid crystal alignment film is formed, and the liquid crystal composition is further dropped at a predetermined number of points on the surface of the liquid crystal alignment film. After that, the other substrate is bonded so that the liquid crystal alignment films face each other, and the liquid crystal composition is spread over the entire surface of the substrate and brought into contact with the film surface. Next, ultraviolet light is irradiated to the entire surface of the substrate to cure the sealant. In either case, it is preferable to further remove the flow orientation during liquid crystal charging by heating the used liquid crystal composition to a temperature at which it assumes an isotropic phase and then slowly cooling it to room temperature.

In addition, when the rubbing treatment is performed on the coating film, the two substrates are arranged to face each other so that the rubbing direction in each coating film is at a predetermined angle, for example, perpendicular or anti-parallel.

As the sealant, for example, an epoxy resin containing a curing agent and aluminum oxide spheres as a spacer can be used. Liquid crystals include nematic liquid crystals and smectic liquid crystals. Among them, nematic liquid crystals are preferable, and examples include fluorine-based liquid crystals, cyano-based liquid crystals, Schiff-based liquid crystals, azo-based liquid crystals, biphenyl-based liquid crystals, and phenyl-based liquid crystals. Cyclohexane-based liquid crystals, ester-based liquid crystals, terphenyl-based liquid crystals, biphenylcyclohexane-based liquid crystals, pyrimidine-based liquid crystals, dioxane-based liquid crystals, bicyclooctane-based liquid crystals, cubane-based liquid crystals, etc. can be used. Moreover, these liquid crystals include, for example, cholesteric liquid crystals such as cholesteryl chloride, cholesteryl nonaate, and cholesteryl carbonate; Chiral agents sold under the brand names “C-15” and “CB-15” (manufactured by Merck & Co., Ltd.); It may be used by adding a ferroelectric liquid crystal such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate. In addition, various things such as those disclosed in Japanese Patent Application Publication No. 2019-132952 can be used.

The above liquid crystals are generally prepared by mixing several liquid crystals to satisfy desired physical properties according to the intended use (hereinafter, the liquid crystal component obtained by mixing a plurality of liquid crystals is also referred to as mixed liquid crystal).

Among these, it is preferable to use fluorine-based mixed liquid crystals that are currently generally used in liquid crystal display devices. Here, the fluorine-based mixed liquid crystal in this specification means a mixed liquid crystal containing one or more types of fluorine-based liquid crystals, and the cyano-based mixed liquid crystal means a mixed liquid crystal containing one or more types of cyano-based liquid crystals.

The above mixed liquid crystal is generally known and commercially available. For example, the fluorine-based mixed liquid crystal is a liquid crystal with a positive dielectric anisotropy Δε (also called positive liquid crystal), under the trade name ZLI-4792, and a dielectric constant Δε. This anisotropic Δε negative liquid crystal (also called negative liquid crystal) is sold by Merck & Co., Ltd. under the brand name MLC-6608. Additionally, cyano-based mixed liquid crystal is a positive type liquid crystal and is sold by Chisso Petrochemical Co., Ltd. under the brand name JC-5066XX. This invention provides, among others, a liquid crystal aligning film suitable for a liquid crystal display element in which a negative liquid crystal is used, and a liquid crystal aligning agent that provides the liquid crystal aligning film.

The liquid crystal aligning agent of the present invention has a liquid crystal layer between a pair of substrates provided with electrodes, and contains a polymerizable compound polymerized between a pair of substrates by at least one of an active energy ray and heat. A liquid crystal display device (PSA type liquid crystal display device) manufactured through a process of arranging a liquid crystal composition and polymerizing a polymerizable compound by at least one of active energy ray irradiation and heating while applying a voltage between electrodes is also preferred. It is used.

Moreover, the liquid crystal aligning agent of this invention has a liquid crystal layer between a pair of board|substrates provided with electrodes, and a polymerizable group polymerized by at least one of an active energy ray and heat between said pair of board|substrates It is also preferably used for a liquid crystal display device (SC-PVA mode liquid crystal display device) manufactured through a process of disposing a liquid crystal alignment film containing and applying a voltage between electrodes.

＜Step (4-2): For PSA type liquid crystal display device＞

The procedure is the same as (4) above except that the liquid crystal composition containing the polymerizable compound is injected or dropped. Examples of the polymerizable compound include polymerizable compounds having one or more polymerizable unsaturated groups such as an acrylate group or a methacrylate group in the molecule.

＜Step (4-3): For SC-PVA mode liquid crystal display device＞

After performing the same procedure as in (4) above, a method of manufacturing a liquid crystal display element through a process of irradiating ultraviolet rays described later may be adopted. According to this method, a liquid crystal display device with excellent response speed can be obtained with a small amount of light irradiation, similar to the case of manufacturing the PSA type liquid crystal display device above. The compound having a polymerizable group may be a compound having one or more of the polymerizable unsaturated groups in the molecule, and its content is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, based on 100 parts by mass of all polymer components. It is the mass part. Moreover, the polymer used for a liquid crystal aligning agent may have the said polymerizable group, Examples of such a polymer include the polymer obtained by using the diamine component containing the diamine which has the said photopolymerizable group at the terminal for reaction. there is.

＜Step (4-4): Process of irradiating ultraviolet rays＞

The liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates obtained in (4-2) or (4-3) above. The voltage applied here can be, for example, direct current or alternating current of 5 to 50 V. In addition, as the light to be irradiated, for example, ultraviolet rays and visible rays containing light with a wavelength of 150 to 800 nm can be used, but ultraviolet rays containing light with a wavelength of 300 to 400 nm are preferable. As a light source of the irradiated light, 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, an excimer laser, etc. can be used. The amount of light irradiated is preferably 1,000 to 200,000 J/m2, and more preferably 1,000 to 100,000 J/m2.

And, if necessary, a liquid crystal display element can be obtained by bonding a polarizing plate to the outer surface of the liquid crystal cell. Examples of the polarizing plate bonded to the outer surface of the liquid crystal cell include a polarizing plate made of a polarizing film called an "H film" in which iodine is absorbed while stretching polyvinyl alcohol and sandwiched with a cellulose acetate protective film, or a polarizing plate made of the H film itself. You can.

And, if necessary, a liquid crystal display element can be obtained by bonding a polarizing plate to the outer surface of the liquid crystal cell. Examples of the polarizing plate bonded to the outer surface of the liquid crystal cell include a polarizing plate made of a polarizing film called an "H film" in which iodine is absorbed while stretching polyvinyl alcohol and sandwiched with a cellulose acetate protective film, or a polarizing plate made of the H film itself. You can.

The IPS substrate, which is a comb electrode substrate used in IPS mode, has a base material, a plurality of linear electrodes formed on the base material and arranged in a comb shape, and a liquid crystal alignment film formed on the base material so as to cover the linear electrodes.

In addition, the FFS substrate, which is a comb electrode substrate used in the FFS mode, includes a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, and a plurality of linear electrodes formed on the insulating film and arranged in a comb shape. and a liquid crystal alignment film formed on the insulating film so as to cover the linear electrode.

1 is a schematic cross-sectional view showing an example of a transverse electric field liquid crystal display device of the present invention, which is an example of an IPS mode liquid crystal display device.

In the transverse electric field liquid crystal display element 1 illustrated in FIG. 1, between the comb electrode substrate 2 provided with the liquid crystal aligning film 2c and the opposing substrate 4 provided with the liquid crystal aligning film 4a, the liquid crystal 3 ) is narrowed down. The comb electrode substrate 2 includes a base material 2a, a plurality of linear electrodes 2b arranged in a comb shape, formed on the base material 2a, and covering the linear electrodes 2b on the base material 2a. It has a liquid crystal alignment film (2c) formed as follows. The opposing substrate 4 has a base material 4b and a liquid crystal aligning film 4a formed on the base material 4b. The liquid crystal aligning film 2c is, for example, the liquid crystal aligning film of the present invention. The liquid crystal aligning film 4c is also a liquid crystal aligning film of the present invention.

In this transverse electric field liquid crystal display element 1, when a voltage is applied to the linear electrodes 2b, an electric field is generated between the linear electrodes 2b as indicated by the electric field line L.

Fig. 2 is a schematic cross-sectional view showing another example of a transverse electric field liquid crystal display device of the present invention, which is an example of an FFS mode liquid crystal display device.

In the transverse electric field liquid crystal display element 1 illustrated in FIG. 2, between the comb electrode substrate 2 provided with the liquid crystal aligning film 2h and the opposing substrate 4 provided with the liquid crystal aligning film 4a, the liquid crystal 3 ) is narrowed down. The comb electrode substrate 2 is formed on a base material 2d, a surface electrode 2e formed on the base material 2d, an insulating film 2f formed on the surface electrode 2e, and the insulating film 2f. It has a plurality of linear electrodes 2g arranged in a comb shape, and a liquid crystal alignment film 2h formed on an insulating film 2f so as to cover the linear electrodes 2g. The opposing substrate 4 has a base material 4b and a liquid crystal aligning film 4a formed on the base material 4b. The liquid crystal aligning film (2h) is, for example, the liquid crystal aligning film of the present invention. The liquid crystal aligning film 4a is also a liquid crystal aligning film of the present invention.

In this transverse electric field liquid crystal display element 1, when a voltage is applied to the surface electrode 2e and the linear electrode 2g, a voltage occurs between the surface electrode 2e and the linear electrode 2g as indicated by the electric field line L. An electric field is generated.

The liquid crystal alignment film of the present invention can be applied to various uses in addition to the liquid crystal alignment film for the above applications, for example, a liquid crystal alignment film for a retardation film, a liquid crystal alignment film for a scanning antenna or a liquid crystal array antenna, or a transmission-scattering type liquid crystal light control film. It can also be used for a liquid crystal alignment film for devices. Furthermore, applications other than the liquid crystal alignment film include protective films (e.g., protective films for color filters), spacer films, interlayer insulating films, antireflection films, wiring coating films, antistatic films, and motor insulating films (gate insulating films in flexible displays). It can also be used.

The liquid crystal display element of the present invention can be effectively applied to various devices, for example, watches, portable games, word processors, laptop computers, car navigation systems, camcorders, PDAs, digital cameras, mobile phones, smartphones, It can be used in various display devices such as various monitors, liquid crystal televisions, and information displays.

Example

Below, the present invention will be described in detail with reference to Examples. However, the present invention is not limited to these Examples. In addition, the abbreviations for compounds and solvents are as follows.

(organic solvent)

NMP: N-methyl-2-pyrrolidone

GBL: γ-butyrolactone

BCS: Butylcellosolve

(diamine)

[Formula 23]

(The diamine of the formula (DA-2) is included in the scope of the diamine represented by the formula (d _n ).)

(Tetracarboxylic dianhydride)

[Formula 24]

(Tetracarboxylic dianhydrides of formulas (CA-3) and (CA-6) are included in the scope of tetracarboxylic dianhydrides represented by formula (T _f ).)

(additive)

AD-1: 3-Glycidoxypropyltriethoxysilane

[Formula 25]

(Measurement of viscosity)

In the synthesis example, the viscosity of the polymer solution was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.), a sample amount of 1.1 mL, a cone rotor TE-1 (1°34', R24), and a temperature of 25°C. did.

＜Synthesis of polyamic acid＞

(Synthesis Example 1)

3.15 g (11.0 mmol) of DA-1 was weighed and placed in a 100 mL eggplant flask equipped with a stirring device and a nitrogen introduction tube, 28.4 g of NMP was added, and the mixture was stirred and dissolved while transferring nitrogen. While stirring this diamine solution under water cooling, 2.37 g (10.6 mmol) of CA-1 was added, 11.6 g of NMP was further added, and the solution was stirred at 40°C in a nitrogen atmosphere for 3 hours to obtain a polyamic acid solution (viscosity: 550). mPa·s) PAA-A1 was obtained.

(Synthesis Example 2)

Weigh 4.78 g (24.0 mmol) of DA-2 and 1.19 g (6.00 mmol) of DA-3 into a 100 mL eggplant flask equipped with a stirring device and a nitrogen inlet tube, add 56.9 g of NMP, and add nitrogen. It was dissolved by stirring while transporting. While stirring this diamine solution under water cooling, 1.35 g (6.90 mmol) of CA-2 was added, 9.0 g of NMP was further added, and the mixture was stirred in a nitrogen atmosphere for 1 hour. Additionally, 5.63 g (22.5 mmol) of CA-3 was added, 7.5 g of NMP was further added, and the mixture was stirred at 50°C for 15 hours in a nitrogen atmosphere to form a polyamic acid solution (viscosity: 530 mPa·s). Got B1.

(Synthesis Example 3)

Weigh 2.99 g (15.0 mmol) of DA-2 and 2.97 g (15.0 mmol) of DA-3 into a 100 mL eggplant flask equipped with a stirring device and a nitrogen inlet tube, add 56.8 g of NMP, and add nitrogen. It was dissolved by stirring while transporting. While stirring this diamine solution under water cooling, 1.24 g (6.32 mmol) of CA-2 was added, 8.0 g of NMP was further added, and the mixture was stirred in a nitrogen atmosphere for 1 hour. Additionally, 5.63 g (22.5 mmol) of CA-3 was added, 7.9 g of NMP was further added, and the mixture was stirred at 50°C for 15 hours under a nitrogen atmosphere to form a solution of polyamic acid (viscosity: 310 mPa·s). I got B2.

(Synthesis Example 4)

Weigh 6.97 g (35.0 mmol) of DA-2 and 6.94 g (35.0 mmol) of DA-3 into a 200 mL eggplant flask equipped with a stirring device and a nitrogen inlet tube, add 102 g of NMP, and add nitrogen. It was dissolved by stirring while transporting. While stirring this diamine solution under water cooling, 8.76 g (35.0 mmol) of CA-3 was added, 26.4 g of NMP was further added, and the mixture was stirred at 50°C in a nitrogen atmosphere for 2 hours. Additionally, 9.54 g (32.4 mmol) of CA-4 was added, 53.7 g of NMP was further added, and the mixture was stirred at 50°C for 15 hours in a nitrogen atmosphere to form a polyamic acid solution (viscosity: 400 mPa·s). I got B3.

(Synthesis Example 5)

Weigh 2.99 g (15.0 mmol) of DA-2 and 2.97 g (15.0 mmol) of DA-3 into a 100 mL eggplant flask equipped with a stirring device and a nitrogen inlet tube, add 53.7 g of NMP, and add nitrogen. It was dissolved by stirring while transporting. While stirring this diamine solution under water cooling, 5.63 g (22.5 mmol) of CA-3 was added, 12.0 g of NMP was further added, and the mixture was stirred at 50°C in a nitrogen atmosphere for 2 hours. Additionally, 1.90 g (6.46 mmol) of CA-4 was added, 10.8 g of NMP was further added, and the mixture was stirred at 50°C for 15 hours under a nitrogen atmosphere to form a polyamic acid solution (viscosity: 340 mPa·s). Got B4.

(Synthesis Example 6)

Weigh 2.99 g (15.0 mmol) of DA-2 and 2.97 g (15.0 mmol) of DA-3 into a 100 mL eggplant flask equipped with a stirring device and a nitrogen inlet tube, add 53.7 g of NMP, and add nitrogen. It was dissolved by stirring while transporting. While stirring this diamine solution under water cooling, 5.63 g (22.5 mmol) of CA-3 was added, 12.0 g of NMP was further added, and the mixture was stirred at 50°C in a nitrogen atmosphere for 2 hours. Additionally, 1.41 g (6.45 mmol) of CA-5 was added, 8.4 g of NMP was further added, and the mixture was stirred at 50°C for 15 hours under a nitrogen atmosphere to form a solution of polyamic acid (viscosity: 340 mPa·s). Got B5.

(Synthesis Example 7)

In a 100 mL eggplant flask equipped with a stirring device and a nitrogen inlet tube, 1.83 g (7.50 mmol) of DA-4, 0.540 g (5.00 mmol) of DA-5, 2.40 g (7.50 mmol) of DA-6, and DA-6 were added. 1.99 g (5.00 mmol) of -7 was weighed, 77.8 g of NMP was added, and it was dissolved by stirring while passing nitrogen. While stirring this diamine solution under water cooling, 5.38 g (24.0 mmol) of CA-1 was added, 11.3 g of NMP was further added, and the solution was stirred at 40°C in a nitrogen atmosphere for 15 hours to obtain a polyamic acid solution (viscosity: 410). mPa·s) PAA-A2 was obtained.

(Synthesis Example 8)

6.87 g (24.0 mmol) of DA-1 was weighed into a 100 mL eggplant flask equipped with a stirring device and a nitrogen inlet tube, 61.9 g of NMP was added, and the mixture was stirred and dissolved while transferring nitrogen. While stirring this diamine solution under water cooling, 5.05 g (23.2 mmol) of CA-5 was added, 25.6 g of NMP was further added, and the solution was stirred at 50°C in a nitrogen atmosphere for 15 hours to form a polyamic acid solution (viscosity: 530). mPa·s) PAA-A3 was obtained.

(Synthesis Example 9)

Weigh 3.66 g (15.0 mmol) of DA-4 and 2.99 g (15.0 mmol) of DA-2 into a 100 mL eggplant flask equipped with a stirring device and a nitrogen introduction tube, add 59.9 g of NMP, and add nitrogen. It was dissolved by stirring while transporting. While stirring this diamine solution under water cooling, 5.63 g (22.5 mmol) of CA-3 was added, 9.7 g of NMP was further added, and the mixture was stirred at 50°C in a nitrogen atmosphere for 2 hours. Additionally, 1.90 g (6.45 mmol) of CA-4 was added, 10.8 g of NMP was further added, and the mixture was stirred at 50°C for 15 hours under a nitrogen atmosphere to form a polyamic acid solution (viscosity: 515 mPa·s). I got B6.

(Synthesis Example 10)

Weigh 4.74 g (23.8 mmol) of DA-2 and 2.02 g (10.2 mmol) of DA-3 into a 100 mL eggplant flask equipped with a stirring device and a nitrogen inlet tube, add 54.7 g of NMP, and add nitrogen. It was dissolved by stirring while transporting. While stirring this diamine solution under water cooling, 3.81 g (17.0 mmol) of CA-6 was added, 5.20 g of NMP was further added, and the mixture was stirred at 50°C in a nitrogen atmosphere for 2 hours. Additionally, 4.40 g (15.0 mmol) of CA-4 was added, 24.7 g of NMP was further added, and the mixture was stirred at 50°C for 15 hours under a nitrogen atmosphere to form a polyamic acid solution (viscosity: 299 mPa·s). I got B7.

(Synthesis Example 11)

Weigh 4.74 g (23.8 mmol) of DA-2 and 3.04 g (10.2 mmol) of DA-8 into a 100 mL eggplant flask equipped with a stirring device and a nitrogen inlet tube, add 63.0 g of NMP, and add nitrogen. It was dissolved by stirring while transporting. While stirring this diamine solution under water cooling, 3.81 g (17.0 mmol) of CA-6 was added, 2.72 g of NMP was further added, and the mixture was stirred at 50°C in a nitrogen atmosphere for 2 hours. Additionally, 4.40 g (15.0 mmol) of CA-4 was added, 24.7 g of NMP was further added, and the mixture was stirred at 50°C for 15 hours under a nitrogen atmosphere to form a polyamic acid solution (viscosity: 330 mPa·s). I got B8.

(Synthesis Example 12)

Weigh 4.74 g (23.8 mmol) of DA-2 and 1.53 g (10.2 mmol) of DA-9 into a 100 mL eggplant flask equipped with a stirring device and a nitrogen inlet tube, add 50.8 g of NMP, and add nitrogen. It was dissolved by stirring while transporting. While stirring this diamine solution under water cooling, 3.81 g (17.0 mmol) of CA-6 was added, 6.38 g of NMP was further added, and the mixture was stirred at 50°C in a nitrogen atmosphere for 2 hours. Additionally, 4.40 g (15.0 mmol) of CA-4 was added, 24.7 g of NMP was further added, and the mixture was stirred at 50°C for 15 hours under a nitrogen atmosphere to form a polyamic acid solution (viscosity: 298 mPa·s). Got B9.

The types and amounts of the diamine component and tetracarboxylic acid derivative component used in Synthesis Examples 1 to 12 are summarized in Table 1. In Table 1, the numbers in parentheses represent the amount (molar parts) of monomer used for a total of 100 molar parts in each component.

<Preparation of liquid crystal aligning agent>

(Examples 1 to 9) and (Comparative Examples 1 to 2)

The polyamic acid solutions obtained in Synthesis Examples 1 to 12 were weighed and mixed so as to obtain a combination of the compositions of Polymer 1 and Polymer 2 shown in the table below. Next, the GBL solution containing 1% by weight of NMP, GBL, BCS, and AD-1, and the NMP solution containing 10% by weight of AD-2 were added with stirring so as to have the composition shown in Table 2 below, and added. Liquid crystal aligning agents (1) to (9) of Examples 1 to 9 and liquid crystal aligning agents (R1) to (R2) of Comparative Examples 1 to 2 were obtained by stirring at room temperature for 2 hours. The specifications of the liquid crystal aligning agent obtained in Examples 1 to 9 and Comparative Examples 1 to 2 are shown in Table 2.

An FFS mode liquid crystal cell was manufactured in the procedure shown below using each liquid crystal aligning agent obtained above, and the pretilt angle and afterimage characteristics by long-term alternating current drive were evaluated. Moreover, using the same liquid crystal aligning agent, a longitudinal electric field liquid crystal cell was manufactured in the procedure shown below, and backlight tolerance evaluation of voltage retention was evaluated.

[Manufacture of FFS mode liquid crystal cell]

First, a glass substrate with a size of 30 mm x 35 mm and a thickness of 0.7 mm on which electrodes were formed was prepared. On the substrate, an IZO electrode with a solid pattern constituting the counter electrode is formed as a first layer, and as a second layer, SiN (silicon nitride) formed into a film by CVD (chemical vapor deposition) method is formed on the counter electrode of the first layer. A membrane was formed. The film thickness of the second layer SiN film, which functions as an interlayer insulating film, was 500 nm. On the SiN film of the second layer, a comb-shaped pixel electrode formed by patterning an IZO film as the third layer is disposed, and two pixels, a first pixel and a second pixel, are formed, and the size of each pixel is 10 mm vertically. and is 5 mm across. At this time, the counter electrode of the first layer and the pixel electrode of the third layer were electrically insulated by the action of the SiN film of the second layer.

The pixel electrode of the third layer has a comb-tooth shape in which a plurality of electrode elements with a width of 3 μm bent at an inner angle of 160° at the center are arranged in parallel at intervals of 6 μm, and one pixel has a plurality of electrodes. Each had a first area and a second area bordered by a line connecting the curved part of the element.

Next, after filtering the liquid crystal aligning agents (1) - (9) and (R1) - (R2) obtained in the said Examples 1 - 9 and Comparative Examples 1 - 2 with a filter with a pore diameter of 1.0 micrometer, the electrode prepared above An ITO film was formed on the surface and back of this formed substrate (first glass substrate), and was applied by spin coating to the surface of a glass substrate (second glass substrate) with a columnar spacer with a height of 4 μm. Next, after drying on an 80 degreeC hot plate for 2 minutes, it baked at 230 degreeC for 20 minutes, and obtained the polyimide film with a film thickness of 60 nm on each board|substrate. This liquid crystal alignment film was rubbed with rayon cloth (roller diameter: 140 mm, roller rotation speed: 1000 rpm, moving speed: 30 mm/sec, press-fit length: 0.3 mm), and then cleaned by ultrasonic irradiation in pure water for 1 minute. , After removing the water droplets by air blowing, it was dried at 80°C for 10 minutes to obtain a substrate on which a liquid crystal alignment film was formed.

Using the two types of substrates on which the liquid crystal alignment film was formed, they were combined so that their respective rubbing directions were antiparallel, and the surrounding area was sealed leaving a liquid crystal injection port, thereby producing an empty cell with a cell gap of 4 μm. Liquid crystal MLC-7026-100 (manufactured by Merck & Co., negative type liquid crystal) was vacuum-injected into this empty cell at room temperature, and then the injection port was sealed to form a liquid crystal cell with anti-parallel orientation. The obtained liquid crystal cell constituted an FFS mode liquid crystal display element. After that, the liquid crystal cell was heated at 120°C for 1 hour, left to stand at 23°C overnight, and then used for each evaluation described below.

[Manufacture of conventional liquid crystal cells]

First, a glass substrate with a size of 30 mm × 40 mm and a thickness of 1.1 mm was prepared. An ITO electrode with a film thickness of 35 nm was formed on the substrate, and the electrode had a stripe pattern of 40 mm in length and 10 mm in width.

Next, after filtering the liquid crystal aligning agents (1) to (9) and (R1) to (R2) obtained in Examples 1 to 9 and Comparative Examples 1 to 2 through a filter with a pore diameter of 1.0 μm, the prepared electrode is It was applied to the formed substrate by spin coating. After drying on an 80 degreeC hotplate for 2 minutes, baking was performed in the 230 degreeC IR oven for 20 minutes, the coating film with a film thickness of 100 nm was formed, and the board|substrate with a liquid crystal alignment film was obtained. This liquid crystal alignment film was rubbed with rayon cloth (roller diameter: 140 mm, roller rotation speed: 1000 rpm, moving speed: 30 mm/sec, press-fit length: 0.3 mm), and then cleaned by ultrasonic irradiation in pure water for 1 minute. , After removing the water droplets by air blowing, it was dried at 80°C for 10 minutes to obtain a substrate on which a liquid crystal alignment film was formed. Two substrates on which this liquid crystal alignment film was formed were prepared, and a spacer of 4 μm was spread on the liquid crystal alignment film surface of one sheet, then a sealant was printed from thereon, and the other substrate was rubbed in the reverse direction and also on the film surface. After attaching them facing each other, the sealant was cured to produce an empty cell. Liquid crystal MLC-7026-100 (Merck & Co., negative type liquid crystal) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain a liquid crystal cell. After that, the obtained liquid crystal cell was heated at 120°C for 1 hour, left to stand overnight at 23°C, and then used for each evaluation.

＜Evaluation of pretilt angle＞

The pretilt angle of the FFS mode liquid crystal cell was evaluated using an AxoScan Mueller matrix polarimeter manufactured by Optometrics. Viewing angle characteristics are better as the pretilt angle is lower. Specifically, if the pretilt angle was less than 2.0°, it was defined as “good”, and if it was 2.0° or more, it was defined as “bad.”

＜Evaluation of afterimage characteristics by long-term AC drive＞

Using the FFS mode liquid crystal cell, an alternating voltage of ±5.5 V was applied at a frequency of 30 Hz for 72 hours under irradiation of a high-brightness backlight (30,000 cd/m 2 ). After that, the state was short-circuited between the pixel electrode of the liquid crystal cell and the counter electrode.

After being left overnight at 23°C, this liquid crystal cell is installed between two polarizers arranged so that their polarization axes are orthogonal, the backlight is turned on in a state where no voltage is applied, and the arrangement angle of the liquid crystal cell is adjusted so that the luminance of the transmitted light is the lowest. Adjusted. Then, the rotation angle when the liquid crystal cell is rotated from the angle at which the second area of the first pixel becomes darkest to the angle at which the first area becomes darkest is calculated as an angle Δθ1, and in the same way for the second pixel, the second area and The angle Δθ2 was calculated by comparing the first area. The average value of these Δθ1 and Δθ2 was set as the angle Δθ of the liquid crystal cell, and the smaller this value was, the better the liquid crystal orientation was defined and evaluated.

Specifically, when this angle Δθ was less than 0.4°, the afterimage characteristics were excellent, that is, it was defined as “good”, and when it was 0.4° or more, it was defined as “poor” for evaluation.

＜Evaluation of backlight immunity of voltage retention rate＞

Using a liquid crystal comprehensive evaluation device manufactured by Toyo Technica Co., Ltd., a voltage of 1 V is applied for 60 μsec at a temperature of 60° C. to the above conventional liquid crystal cell, and the voltage after 16.67 msec is measured to determine how much the voltage is maintained. It was evaluated as voltage maintenance rate. This value was set to VHR _ini .

Next, the vertical electric field liquid crystal cell was left to stand for 72 hours under irradiation of a high-brightness backlight (30,000 cd/m 2 ), and the voltage retention rate was measured in the same manner as the VHR _ini . This value was taken as VHR _BLU .

When this VHR _BLU was 90% or more, the aging resistance of the backlight was excellent, that is, it was defined as "good", and when it was less than 90%, it was defined as "poor" and evaluated.

The evaluation results performed on the liquid crystal display elements using each liquid crystal aligning agent of Examples 1 to 9 and Comparative Examples 1 to 2 are shown in Table 3 below.

As shown in the table above, the liquid crystal display elements using the liquid crystal aligning agents of Comparative Examples 1 to 2 were defective in at least any of the backlight resistance of viewing angle characteristics, afterimage characteristics and voltage retention, whereas the liquid crystal display elements of the present invention in Examples 1 to 9 were defective. The liquid crystal display element using the liquid crystal aligning agent had good viewing angle characteristics, afterimage characteristics, and backlight resistance in terms of voltage retention. From the above, it can be said that the liquid crystal display element using the liquid crystal aligning agent of the present invention has a small pretilt angle, good afterimage characteristics, and good resistance to backlight aging in voltage retention.

1: Transverse electric field liquid crystal display device
2: Comb electrode substrate
2a, 4b, 2d: description
2b, 2g: linear electrode
2c, 2h, 4a: liquid crystal alignment film
2e: cotton electrode
2f: insulating film
3: liquid crystal
4: Opposite substrate
L: electric field lines
In addition, the entire contents of the specification, claims, drawings, and abstract of Japanese Patent Application No. 2021-115168 filed on July 12, 2021 are hereby cited and accepted as disclosure of the specification of the present invention.

Claims (12)

A liquid crystal aligning agent characterized by containing the following (A) component and (B) component.
(A) Component: Selected from the group consisting of polyimide precursors having 60 mol% or more of repeating units represented by the following formula (1) relative to 1 mole of all repeating units in the polymer, and polyimides that are imidates of the polyimide precursors. At least one polymer (A).
(B) Component: a tetracarboxylic acid derivative component containing 5 mol% or more of tetracarboxylic acid dianhydride represented by the following formula (T _f ) based on the total tetracarboxylic acid derivative components, and a tetracarboxylic acid derivative represented by the following formula (d _n ) At least one type of polymer (B) selected from the group consisting of a polyimide precursor that is a reaction product of a diamine component containing diamine, and a polyimide that is an imidate of the polyimide precursor.

(R ₁₁ to R ₁₄ are each independently a hydrogen atom, a halogen atom, an alkyl group with 1 to 6 carbon atoms, an alkenyl group with 2 to 6 carbon atoms, an alkynyl group with 2 to 6 carbon atoms, or a fluorine atom containing 1 to 6 carbon atoms. represents a monovalent organic group or a phenyl group, and at least one of R ₁₁ to R ₁₄ represents a group other than a hydrogen atom as defined above. Ar ₁ and Ar _1' each represent a benzene ring, and one or more groups on the benzene ring. The hydrogen atom may be substituted with a monovalent group. L ₁ and L _1' represent a single bond, -O-, -C(=O)-, and -OC(=O)-, respectively. A has 5 carbon atoms. It represents an alkylene group of to 12 or a divalent organic group (Qa) formed by inserting either -O- or -C(=O)-O- between the carbon-carbon bonds of the alkylene group. However, L ₁ and when L _1' represents a single bond, A represents a divalent organic group (Qa), R ₁ and Z ₁ each independently represent a hydrogen atom or a monovalent organic group having 1 to 5 carbon atoms, and represent two R ₁ and Z ₁ may each be the same or different.)

(X _f is a tetravalent organic group having an alicyclic structure of 5 or more membered rings.)

(Y represents a nitrogen atom-containing heterocycle and group "*21-NR-*22" (*21, and *22 represent a bond bonding to a carbon atom constituting an aromatic ring. However, the carbon atom It does not form a ring with the nitrogen atom to which R is bonded. R represents a hydrogen atom or a monovalent organic group, and the monovalent organic group is bonded to the nitrogen atom with a carbon atom other than the carbonyl carbon.) In the group consisting of the amino group represented by represents a divalent organic group having a selected nitrogen atom-containing structure.) According to claim 1,
The group -L ₁ -AL _1' - in the above formula (1) is any of the following (n is an integer from 5 to 12. The sum of n1 and n2 is an integer from 5 to 12. m1 , m2 and n', the total of them is an integer of 5 to 12.), liquid crystal aligning agent.
The method of claim 1 or 2,
The liquid crystal aligning agent whose content of the diamine represented by the said formula (d _n ) in the structural component of the said polymer (B) is 20-95 mol% of all the diamine components used for manufacture of the said polymer (B). The method according to any one of claims 1 to 3,
The diamine represented by the formula (d _n ) is 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, and N-methyl-3. ,6-diaminocarbazole, 1,4-bis-(4-aminophenyl)-piperazine, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl- A liquid crystal aligning agent that is at least one type of diamine selected from the group consisting of 3,6-diaminocarbazole and diamines represented by the following formulas (d _n -1) to (d _n -3).

(In the formula (d _n -1), m1 and m1' are each independently an integer of 1 to 2. n1 is _an integer of 1 to 3. R ₁ is " It has the same meaning as R in the amino group represented by “*21-NR-*22”.
When a plurality of R ₁ and m1' exist, the plurality of R ₁ and m1' may be the same or different.
In the formula (d _n -2), X ₂ represents a monovalent nitrogen atom-containing heterocyclic group. n1 is an integer of 1 to 2, and n2 is an integer that satisfies n1 + n2 = 2. L ₁ and L ₂ are each independently a single bond, -CO-, an alkylene group having 1 to 6 carbon atoms, or between or at the carbon-carbon bond of the alkylene group having 1 to 6 carbon atoms, -O- or It is a divalent organic group with -CO- inserted, and represents a divalent organic group bonded to a nitrogen atom and a carbon atom. R represents a hydrogen atom or a methyl group.
When a plurality of X ₂ , L ₂ , and R exist, the plurality of X ₂ , L ₂ , and R may be the same or different.
In the formula (d _n -3), X ₃ represents a divalent group having a nitrogen atom-containing heterocycle. Ar ₃ represents a divalent aromatic ring group or a divalent saturated nitrogen atom-containing heterocyclic group. Arbitrary hydrogen atoms of the aromatic ring group and the saturated nitrogen atom-containing heterocyclic group may be substituted with a monovalent group.
L ₃ is a single bond, -(CH ₂ ) _n - (n is an integer from 1 to 6), -NR'-, -(CH ₂ ) _n -NR'- (n is an integer from 1 to 6) .), -O-, -NR'-CO-, -CO-NR'-, -O-CO-, or -CO-O-, and R' is a hydrogen atom, a methyl group, or tert-butoxycarbonyl group. represents.
m3 and m3' are each independently an integer of 0 to 2, and either m3 or m3' is an integer of 1 or more.
When a plurality of Ar ₃ and L ₃ exist, the plurality of Ar ₃ and L ₃ may be the same or different.
However, both NH ₂ groups at both ends of the formula (d _n -3) are bonded to the carbon atoms constituting the aromatic ring.) According to claim 4,
The diamines represented by the above formulas (d _n -1) to (d _n -3) are diamines represented by the following formulas (Dp-1) to (Dp-6), and the following formulas (z-1) to (z- 14) A liquid crystal aligning agent which is a diamine selected from the diamines represented by .

The method according to any one of claims 1 to 5,
As a diamine component for obtaining the polymer (B), p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,2'-dimethyl-4,4'-diaminobiphenyl , 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'- Diaminobiphenyl, 2,2'-difluoro-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 2,2'-bis ( Trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 4 ,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 1,2-bis(4-aminophenyl)ethane, 1,2-bis(3-aminophenyl)ethane, 1, 3-bis(4-aminophenyl)propane, 1,3-bis(3-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1,4-bis(3-aminophenyl)butane, 1,5-bis(4-aminophenyl)pentane, 1,5-bis(3-aminophenyl)pentane, 1,6-bis(4-aminophenyl)hexane, 1,6-bis(3-aminophenyl) Hexane, 4,4'-diaminobenzophenone, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(4-aminobenzyl)benzene , bis (4-aminophenoxy) methane, 1,2-bis (4-aminophenoxy) ethane, 1,2-bis (4-amino-2-methylphenoxy) ethane, 1,3-bis (4 -Aminophenoxy)propane, 1,4-bis(4-aminophenoxy)butane, 4-(2-(4-aminophenoxy)ethoxy)-3-fluoroaniline, 4-amino-4'- (2-(4-aminophenoxy)ethoxy)biphenyl, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, amide A liquid crystal aligning agent using at least one type of diamine selected from the group consisting of diamine having a bond or a urea bond, and 4-(2-(methylamino)ethyl)aniline. The method according to any one of claims 1 to 6,
A liquid crystal aligning agent in which X _f of the formula (T _f ) is a tetravalent organic group represented by any of the following formulas (X _f -1) to (X _f -17).

(* indicates a binding hand.) The method according to any one of claims 1 to 7,
The liquid crystal aligning agent whose content ratio of the said (A) component and (B) component is 10/90 - 90/10 by mass ratio of [(A) component]/[(B) component]. The method according to any one of claims 1 to 8,
The liquid crystal aligning agent is a crosslinkable compound (c-1) having at least one substituent selected from an epoxy group, an oxetane group, an oxazoline group, a cyclocarbonate group, a blocked isocyanate group, a hydroxy group, and an alkoxy group, and polymerization. At least one crosslinkable compound selected from the group consisting of crosslinkable compounds (c-2) having a sexually unsaturated group, a functional silane compound, a metal chelate compound, a curing accelerator, a surfactant, an antioxidant, a sensitizer, a preservative, and A liquid crystal aligning agent that further contains at least one additive component selected from the group consisting of compounds for adjusting the dielectric constant or electrical resistance of the resin film. A liquid crystal aligning film formed using the liquid crystal aligning agent according to any one of claims 1 to 9. A liquid crystal display element comprising the liquid crystal alignment film according to claim 10. A method for manufacturing a liquid crystal display element, comprising the following steps (1) to (3).
Process (1): A process of applying the liquid crystal aligning agent according to any one of claims 1 to 9 on a substrate.
Step (2): A step of baking the applied liquid crystal aligning agent to obtain a film.
Step (3): A step of subjecting the film obtained in step (2) to an orientation treatment.

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