KR102393693B1 - Liquid crystal aligning agent, liquid crystal aligning film and liquid crystal display element - Google Patents

Abstract

(B) 성분 : 하기 식 (2) 로 나타내는 부분 구조를 2 개 이상 가지며, 또한 분자량이 2,500 이하인 화합물

The liquid crystal aligning agent containing following (A) component and (B) component. In addition, the definition of the symbol in each following formula is as described in the specification. (A) component: at least selected from the group consisting of a polyimide precursor obtained by reacting a diamine component containing a diamine of the following formula (1) with a tetracarboxylic acid derivative component, and a polyimide obtained by ring closure of the polyimide precursor 1 type of polymer

(B) component: a compound having two or more partial structures represented by the following formula (2) and having a molecular weight of 2,500 or less

Description

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

TECHNICAL FIELD This invention relates to a novel liquid crystal aligning agent, a liquid crystal aligning film, and a liquid crystal display element.

DESCRIPTION OF RELATED ART A liquid crystal display element is currently widely used as a display device which implement|achieves thinness and light weight. Usually, a liquid crystal aligning film is used for this liquid crystal display element in order to determine the orientation state of a liquid crystal.

As a polymer used for a liquid crystal aligning film, polyimide, polyamide, polyamideimide, etc. are known, and the liquid crystal aligning agent which melt|dissolved these polymers and its precursor in the solvent is generally used.

In recent years, large-screen and high-definition liquid crystal televisions are widely put to practical use, and the liquid crystal display element in such a use is calculated|required by the characteristic which can withstand long-term use in a harsh use environment. Therefore, the liquid crystal aligning film used there is required to be more reliable than the prior art. With respect to such a subject, the liquid crystal aligning agent using a specific additive is proposed (refer patent document 1).

International Publication No. 2010/074269

In recent years, the brightness|luminance of the backlight BL used for a liquid crystal display element is rising further, and the outstanding light resistance and relaxation characteristic far exceeding the conventional level also about the orientation stability of a liquid crystal aligning film, and an electrical property are calculated|required.

As a result of intensive studies, the present inventors have selected from the group consisting of a polyimide precursor obtained by reacting a diamine component containing a diamine of a specific structure with a tetracarboxylic acid derivative component, and a polyimide obtained by ring-closing the polyimide precursor. With the liquid crystal aligning agent containing a polymer and the compound of a specific structure, it found out that said subject could be achieved, and led to this invention.

The 1st aspect of this invention which achieves the said objective exists in the liquid crystal aligning agent containing the following (A) component and (B) component.

(A) component: at least selected from the group consisting of a polyimide precursor obtained by reacting a diamine component containing a diamine of the following formula (1) with a tetracarboxylic acid derivative component, and a polyimide obtained by ring closure of the polyimide precursor 1 type of polymer

[Formula 1]

(In formula (1), R ₁ represents hydrogen or a monovalent organic group. Q ₁ represents alkylene having 1 to 5 carbon atoms. Cy represents azetidine, pyrrolidine, piperidine or hexamethyleneimine. It is a divalent group representing an aliphatic heterocyclic ring, and a substituent may be bound to these ring moieties.R ₂ and R ₃ are each independently a monovalent organic group. q and r are each independently 0 to 4 It is an integer, provided that, when the sum of q and r is 2 or more, a plurality of R ₂ and R ₃ have the above definition.)

(B) component: a compound having two or more structures of the following formula (2) and having a molecular weight of 2,500 or less

[Formula 2]

(in formula (2), R ¹ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ² and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or * ³ -CH ₂ -OR ¹¹ (R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, "* ³ " represents a bond with the carbon atom to which R ² and R ³ are bonded.), "* ¹ " and "* ² " indicates that it is a bond with another atom.)

The 2nd aspect of this invention which achieves the said objective exists in the liquid crystal aligning agent of a 1st aspect in which diamine of said Formula (1) is represented by following formula (3).

[Formula 3]

(In formula (3), R ₁ is a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group, R ₂ and R ₃ are each independently a hydrogen atom or a methyl group, and Q ₁ is a C 1 to C 5 group straight chain alkylene.)

The 3rd aspect of this invention which achieves the said objective is a 1st aspect or 2nd aspect whose content rate of the diamine represented by said Formula (1) is 1 mol% - 80 mol% with respect to 1 mol of all diamine components of liquid crystal aligning agent.

The 4th aspect of this invention which achieves the said objective exists in the liquid crystal aligning agent in any one of the 1st aspect thru|or 3rd aspect whose compound of the said (B) component is at least 1 type of compound chosen from a following formula .

[Formula 4]

The 5th aspect of this invention which achieves the said objective further contains the polyimide precursor containing the structural unit of following formula (5) as (C)component, the liquid crystal orientation of a 1st aspect - a 4th aspect is on the

[Formula 5]

(In formula (5), X ₂ is a tetravalent organic group derived from a tetracarboxylic acid derivative, Y ₂ is a divalent organic group derived from diamine, and R ₄ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; , Z ₁ and Z ₂ are each independently a hydrogen atom, an optionally substituted C1-C10 alkyl group, a C2-C10 alkenyl group, or a C2-C10 alkynyl group.)

The 6th aspect of this invention which achieves the said objective exists in the liquid crystal aligning agent of a 5th aspect containing the polyimide precursor containing the structural unit whose X< ₂ > in said Formula (5) is the following structure.

The 7th aspect of this invention which achieves the said objective exists in the liquid crystal aligning film obtained from the liquid crystal aligning agent in any one of a 1st aspect - a 6th aspect.

The 8th aspect of this invention which achieves the said objective exists in the liquid crystal display element provided with the liquid crystal aligning film of a 7th aspect.

According to the liquid crystal aligning agent of this invention, the liquid crystal aligning film excellent in BL tolerance, orientation stability, and a relaxation characteristic is obtained.

The liquid crystal aligning agent of this invention contains (A) component and (B) component. Hereinafter, each constituent requirement will be described in detail.

<(A) component>

Polyimide precursor obtained by making (A) component contained in the liquid crystal aligning agent of this invention react the diamine component containing the diamine (henceforth a specific diamine) of following formula (1), and a tetracarboxylic-acid derivative component; And it is at least 1 sort(s) of polymer chosen from the group which consists of a polyimide obtained by ring-closing this polyimide precursor.

[Formula 6]

In said formula (1), R< ₁ > represents hydrogen or a monovalent organic group, Preferably it is a hydrogen atom or a C1-C3 linear alkyl group, More preferably, it is a hydrogen atom or a methyl group.

Moreover, R< ₁ > may raise|generate a desorption reaction by heat|fever, and the protective group substituted by the hydrogen atom may be sufficient as it. From the point of storage stability of a liquid crystal aligning agent, this protecting group does not detach|desorb at room temperature, Preferably it is 80 degreeC or more, More preferably, it is 100 degreeC or more, Especially preferably, it detach|desorbs at 150-200 degreeC, and a hydrogen atom It is preferable to be For example, 1,1-dimethyl-2-chloroethoxycarbonyl group, 1,1-dimethyl-2-cyanoethoxycarbonyl group, tert-butoxycarbonyl group, etc. are mentioned, Preferably, tert-butoxycarbonyl group is mentioned. am.

Q< ₁ > represents a C1-C5 alkylene group, From the point of synthesis simplicity, Preferably, it is a C1-C5 linear alkylene. Cy is a divalent group representing an aliphatic heterocyclic ring consisting of azetidine, pyrrolidine, piperidine, or hexamethyleneimine, and from the viewpoint of simplicity of synthesis, azetidine, pyrrolidine, or piperidine is preferable. . Moreover, the substituent may couple|bond with these ring moieties.

R ₂ and R ₃ are each independently a monovalent organic group, and q and r are each independently an integer of 0 to 4; However, when the sum total of q and r is 2 or more, some R< ₂ > and R< ₃ > has the said definition. In view of simplicity of synthesis, preferably, R ₂ and R ₃ are methyl groups.

In addition, the bonding position of the amino group in the benzene ring constituting the diamine is not limited, and each amino group is at the 3-position or 4-position with respect to the nitrogen atom on Cy, and at the nitrogen atom where Q ₁ and R ₁ are bonded. It is preferably at the 3-position or 4-position, and more preferably at the 4-position with respect to the nitrogen atom on Cy and the 4-position with respect to the nitrogen atom to which Q ₁ and R ₁ are bonded.

It is thought that the structure considered as one of the factors exhibiting the effect of this invention is the structure (henceforth a specific structure) which removed two primary amino groups from the diamine of said Formula (1). Therefore, without using the diamine of the said Formula (1), using the diamine compound containing two or more specific structures, or tetracarboxylic dianhydride which has a specific structure, used for the liquid crystal aligning agent of this invention Although it is thought that a specific structure may be introduce|transduced into a polymer, it is preferable to use the diamine of the said Formula (1) from the convenience of a synthesis|combination.

It is preferable that the diamine represented by said Formula (1) of this invention is a compound represented by following formula (3).

[Formula 7]

In the formula (3), R ₁ is a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group. R ₂ and R ₃ are each independently a hydrogen atom or a methyl group. Q ₁ is a linear alkylene having 1 to 5 carbon atoms.

As a specific example of the diamine represented by the said Formula (3), the diamine represented by a following formula (3-1) - a following formula (3-10) is mentioned, for example. In the following formula, Boc represents a tert-butoxycarbonyl group.

[Formula 8]

<(B) component>

(B) component contained in the liquid crystal aligning agent of this invention is a compound which has two or more structures of following formula (2), and molecular weight is 2,500 or less.

[Formula 9]

In said formula (2), R< ¹ > represents a hydrogen atom or a C1-C3 alkyl group.

R ² and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or * ³ -CH ₂ -OR ¹¹ (R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, "* ³ " represents a bond with the carbon atom to which R ² and R ³ are bonded.) and "* ¹ " and "* ² " indicate that they are a bond with another atom.

As a C1-C3 alkyl group of R< ¹ > and R< ¹¹ >, a methyl group, an ethyl group, n-propyl group, and isopropyl group are mentioned, for example. Preferably it is a hydrogen atom or a methyl group, More preferably, it is a hydrogen atom. In addition, R ¹ and R ¹¹ may be the same as or different from each other.

Examples of the alkyl group having 1 to 3 carbon atoms for R ² and R ³ include the groups exemplified for R ¹ above. preferably a hydrogen atom, * ³ -CH ₂ -OH, or * ³ -CH ₂ -OCH ₃ . In addition, R ² and R ³ may be the same as or different from each other.

As the group bonded to the nitrogen atom in the formula (2) (hereinafter referred to as “R ⁴ ”), for example, a hydrogen atom, a monovalent organic group, or a carbonyl group in the formula (2) and the nitrogen atom and a divalent organic group to be bonded. Moreover, when R< ⁴ > is the said divalent organic group, a ring structure is formed with the nitrogen atom and carbonyl group in said Formula (2).

The number of the structures represented by the said Formula (2) in the compound of (B) component of this invention is 2 or more, Preferably it is 2-8 pieces, More preferably, they are 2-6 pieces. The number of groups "* ⁴ -CH ₂ -OR ¹ ("* ⁴ " represents a bond with a carbon atom. R ¹ has the same definition as above)" in the compound (B) is 2 per molecule It is preferable that it is more than it, The thing of 3-8 is more preferable, The thing of 3-6 is still more preferable.

As a preferable specific example of the structure of said Formula (2), the compound etc. which are represented by each of following formula (2-1) - following formula (2-6) are mentioned, for example.

[Formula 10]

In said Formula (2-1) - said Formula (2-5), "* ¹ " shows that it is a bond. In formula (2-5), R< ⁵ > is a C1-C3 alkyl group. "* ¹ " and "* ⁵ " in the said Formula (2-6) show that it is a bond couple|bonded with the group which forms a ring with the nitrogen atom and the carbonyl group in said Formula (2-6).

The molecular weight of the compound (B) is 2,500 or less. From a viewpoint of making the solubility with respect to a solvent and the applicability|paintability of a liquid crystal aligning agent favorable, it is preferable that the said molecular weight is 2,000 or less, and it is more preferable that it is 1,200 or less.

As a specific example of a compound (B), the compound etc. which are represented by a following formula are mentioned, for example.

[Formula 11]

It is preferable that the compounding ratio of a compound (B) sets it as 0.1 weight part - 100 weight part with respect to a total of 100 weight part of the polymer component contained in a liquid crystal aligning agent. The lower limit of the more preferable compounding ratio of a compound (B) is 1 weight part or more with respect to a total of 100 weight part of the polymer component contained in a liquid crystal aligning agent, More preferably, it is 3 weight part or more. Moreover, about the upper limit of the said compounding ratio, More preferably, it is 50 weight part or less, More preferably, it is 20 weight part or less. In addition, a compound (B) can be used individually by 1 type or in combination of 2 or more type.

<Polyimide precursor and polyimide>

The polyimide precursor contained in the liquid crystal aligning agent of this invention is a polyimide precursor obtained by reaction of the diamine component containing the diamine represented by said Formula (1), and a tetracarboxylic-acid derivative component. Here, a polyimide precursor is a polyamic acid or polyamic acid ester.

Examples of the tetracarboxylic acid derivative include acid dianhydride, dicarboxylic acid diester, and diester dicarboxylic acid chloride.

A polyamic acid is obtained by making a diamine component and acid dianhydride react, and polyamic acid ester is obtained by reaction of a diamine component, dicarboxylic acid diester, or diester dicarboxylic acid chloride.

The polyimide contained in the liquid crystal aligning agent of this invention is a polyimide obtained by ring-closing these polyimide precursors, All are useful as a polymer for obtaining a liquid crystal aligning film.

The polyimide precursor contained in the liquid crystal aligning agent of this invention is a polymer containing the structural unit represented by following formula (4).

[Formula 12]

In said formula (4), X< ₁ > is a tetravalent organic group derived from a tetracarboxylic-acid derivative, Y< ₁ > is a divalent organic group derived from the diamine of formula (1), R< ₄ > is a hydrogen atom or C1 to 5 alkyl groups. From the viewpoint of easiness of imidation by heating, R ₄ is preferably a hydrogen atom, a methyl group, or an ethyl group.

The diamine component for obtaining the said polyimide precursor WHEREIN: Although there is no restriction|limiting in the content rate of the diamine represented by the said Formula (1), The effect of this invention is easy to be acquired by many. As for the ratio of the diamine represented by said Formula (1), 1 mol% - 80 mol% are preferable with respect to 1 mol of all the diamine components, More preferably, 5 mol% - 60 mol%, More preferably, 10 mol% -40 mol%.

X ₁ is not particularly limited as long as it is a tetravalent organic group. Two or more types of X< ₁ > may be mixed in a polyimide precursor.

If the specific example of X< ₁ > is shown, the structure of a following formula (X1-1) - a following formula (X1-44) will be mentioned. From the point of availability, a following formula (X1-1) - a following formula (X1-14) are more preferable.

[Formula 13]

[Formula 14]

[Formula 15]

[Formula 16]

[Formula 17]

[Formula 18]

In the formulas (X1-1) to (X1-4), R ₅ to R ₂₅ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms; They are a C2-C6 alkynyl group, a C1-C6 monovalent organic group containing a fluorine atom, or a phenyl group, and may be same or different. From a viewpoint of liquid-crystal orientation, a hydrogen atom, a halogen atom, a methyl group, or an ethyl group is preferable, and, as for R5 _{- R25} , a hydrogen atom or a methyl group is more preferable. As a specific structure of the said Formula (X1-1), the structure represented by a following formula (X1-1-1) - a following formula (X1-1-6) is mentioned. The following formula (X1-1-1) is especially preferable from a viewpoint of the liquid-crystal orientation and the sensitivity of a photoreaction.

[Formula 19]

Moreover, the polyimide precursor of this invention may contain the structural unit represented by following formula (5) in the range which does not impair the effect of this invention other than said Formula (4). Moreover, when the liquid crystal aligning agent of this invention contains polyimide precursors other than the polyimide precursor containing the structural unit represented by said Formula (4), even if it is a polyimide precursor which has a structural unit represented by following formula (5) do.

[Formula 20]

In the formula (5), R ₄ is the same as defined in the formula (4). X2 is _a tetravalent organic group, It is the same as that of the definition of X< ₁ > in said Formula (4) including a preferable example. However, when the liquid crystal aligning agent of this invention contains the polyimide precursor containing the structural unit of the said Formula (5) other than the polyimide precursor containing the structural unit represented by the said Formula (4), the effect of the liquid crystal aligning film obtained From the viewpoint of expression, the above formula (X1-8) is particularly preferred. Z ₁ and Z ₂ are each independently a hydrogen atom, an optionally substituted C1-C10 alkyl group, a C2-C10 alkenyl group, or a C2-C10 alkynyl group.

Specific examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a t-butyl group, a hexyl group, an octyl group, a decyl group, a cyclopentyl group, a cyclohexyl group, a bicyclohexyl group, etc. can be heard

Examples of the alkenyl group having 2 to 10 carbon atoms include those in which one or more CH ₂ -CH ₂ present in the alkyl group is substituted with CH=CH. More specifically, vinyl group, allyl group, 1-propenyl group, isopropenyl group, 2-butenyl group, 1,3-butadienyl group, 2-pentenyl group, 2-hexenyl group, cyclopropenyl group, cyclopentene group A nyl group, a cyclohexenyl group, etc. are mentioned.

Examples of the alkynyl group having 2 to 10 carbon atoms include those in which one or more CH ₂ -CH ₂ present in the alkyl group is substituted with C≡C. More specifically, an ethynyl group, 1-propynyl group, 2-propynyl group, etc. are mentioned.

The alkyl group having 1 to 10 carbon atoms, the alkenyl group having 2 to 10 carbon atoms, and the alkynyl group having 2 to 10 carbon atoms may have a substituent within the range in which the total number of carbon atoms, including the substituent, does not exceed 10, and further You may form ring structure with a substituent. In addition, the formation of a ring structure by a substituent means that substituents or a substituent and a part of parental skeleton couple|bond to form a ring structure.

Examples of the substituent include a halogen group, a hydroxyl group, a thiol group, a nitro group, an aryl group, an organooxy group, an organothio group, an organosilyl group, an acyl group, an ester group, a thioester group, a phosphoric acid ester group, an amide group, an alkyl group. , an alkenyl group, an alkynyl group, and the like.

Polyimide precursor WHEREIN: Generally, when introduce|transducing a bulky structure, since the reactivity of an amino group and liquid-crystal orientation may be reduced, as Z< ₁ > and Z< ₂ >, C1-C1-C which may have a hydrogen atom or a substituent The alkyl group of 5 is more preferable, and a hydrogen atom, a methyl group, or an ethyl group is especially preferable.

In the formula (5), Y ₂ is a divalent organic group derived from a diamine component other than the formula (1), and the structure thereof is not particularly limited. If the specific example of Y< ₂ > is given, a following formula (Y-1) - a following formula (Y-49), a following formula (Y-57) - a following formula (Y-114) will be mentioned. Moreover, 2 or more types may be mixed with a diamine component.

[Formula 21]

[Formula 22]

[Formula 23]

[Formula 24]

[Formula 25]

[Formula 26]

[Formula 27]

[Formula 28]

[Formula 29]

[Formula 30]

[Formula 31]

[Formula 32]

[Formula 33]

[Formula 34]

[Formula 35]

[Formula 36]

[Formula 37]

[Formula 38]

[Formula 39]

In said formula (Y-158), said formula (Y-162) - said formula (Y-165), n is an integer of 1-6.

[Formula 40]

Boc in the formulas (Y-174), (Y-175), (Y-178) and (Y-179) represents a tert-butoxycarbonyl group.

<Method for producing polyamic acid>

The polyamic acid which is a polyimide precursor used for the liquid crystal aligning agent of this invention can make the diamine component containing the diamine of this invention, and a tetracarboxylic-acid derivative component react, and can be obtained.

Specifically, it is compoundable by making tetracarboxylic dianhydride and diamine react in presence of an organic solvent.

It will not specifically limit, if the produced|generated polyamic acid melt|dissolves as an organic solvent. Specific examples include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, dimethylsulfoxide, and γ-butyrolactone. Moreover, when the solubility of a polyimide precursor is high, methyl ethyl ketone, cyclohexanone, a cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or a following formula (D-1) - a following formula (D) The organic solvent represented by -3) can be used.

[Formula 41]

In the formula (D-1), D ¹ represents an alkyl group having 1 to 3 carbon atoms, in the formula (D-2), D ² represents an alkyl group having 1 to 3 carbon atoms, and in the formula (D-3) , D ³ represents an alkyl group having 1 to 4 carbon atoms.

These may be used independently and may be mixed and used for them. Furthermore, even if it is a solvent in which a polyamic acid is not dissolved independently, you may use it in the range in which the produced|generated polyamic acid does not precipitate, mixing with the said solvent. Moreover, since the water|moisture content in an organic solvent inhibits a polymerization reaction and becomes a cause to hydrolyze the produced|generated polyamic acid by extension, it is preferable to use what made the organic solvent dehydrated and dried as much as possible.

As a method of mixing a diamine component and tetracarboxylic dianhydride in an organic solvent, a solution in which diamine is dispersed or dissolved in an organic solvent is stirred, and tetracarboxylic dianhydride is dispersed or dissolved in an organic solvent as it is or The method of adding, the method of adding diamine to the solution which disperse|distributed or dissolved tetracarboxylic dianhydride in the organic solvent, the method of adding tetracarboxylic dianhydride and diamine to the organic solvent alternately or simultaneously, etc. are mentioned. and any of these methods may be used.

Although the temperature at the time of the synthesis|combination of a polyamic acid can select arbitrary temperatures of -20 degreeC - 150 degreeC, Preferably it is the range of -5 degreeC - 100 degreeC, More preferably, it is 0 degreeC - 80 degreeC.

Moreover, although reaction time can be arbitrarily selected in the range longer than the time which superposition|polymerization of a polyamic acid stabilizes, Preferably they are 30 minutes - 24 hours, More preferably, they are 1 hour - 12 hours.

Although the reaction can be carried out at any concentration, when the concentration of the diamine component and tetracarboxylic dianhydride as raw materials is too low, it becomes difficult to obtain a high molecular weight polymer, and when the concentration is too high, the viscosity of the reaction solution is too high. Since it becomes high and uniform stirring becomes difficult, Preferably they are 1 mass % - 50 mass %, More preferably, they are 5 mass % - 20 mass %. In the initial stage of the reaction, it is carried out at a high concentration, and thereafter, an organic solvent may be added.

Synthesis reaction of a polyamic acid WHEREIN: It is preferable that ratio of the number of moles of tetracarboxylic dianhydride with respect to the number of moles of a diamine component is 0.8-1.2. As in a normal polycondensation reaction, the molecular weight of the polyamic acid produced|generated becomes large, so that this molar ratio is close to 1.0.

The polyamic acid obtained as mentioned above can deposit a polymer and collect|recover by injecting|pouring into a poor solvent, stirring a reaction solution well. Moreover, the powder of the refined polyamic acid can be obtained by performing precipitation for several times and making it room temperature or heat-drying after washing|cleaning with a poor solvent.

Although the poor solvent is not specifically limited, Water, methanol, ethanol, 2-propanol, hexane, a butyl cellosolve, acetone, toluene, etc. are mentioned, Water, methanol, ethanol, 2-propanol, etc. are preferable.

<Production of polyamic acid ester>

The polyamic acid ester which is a polyimide precursor of this invention can be manufactured by the manufacturing method of [1], [2], or [3] shown below.

[1] In case of manufacturing from polyamic acid

Polyamic acid ester can be manufactured by esterifying the polyamic acid manufactured as mentioned above.

Specifically, a polyamic acid and an esterification agent are -20 degreeC - 150 degreeC in presence of an organic solvent, Preferably it is 0 degreeC - 50 degreeC for 30 minutes - 24 hours, Preferably it reacts for 1 hour - 4 hours It can be manufactured by

The esterifying agent is preferably one that can be easily removed by purification, and includes N,N-dimethylformamide dimethyl acetal, N,N-dimethylformamide diethyl acetal, N,N-dimethylformamide dipropyl acetal, N,N-dimethylformamide dineopentylbutyl acetal, N,N-dimethylformamide di-t-butyl acetal, 1-methyl-3-p-tolyltriazine, 1-ethyl-3-p-tolyltriazine , 1-propyl-3-p-tolyltriazine, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride, and the like. As for the addition amount of an esterification agent, 2 molar equivalent - 6 molar equivalent are preferable with respect to 1 mol of repeating units of a polyamic acid.

As the organic solvent, for example, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide , dimethyl sulfoxide or 1,3-dimethyl-imidazolidinone. Moreover, when the solubility with respect to the solvent of a polyimide precursor is high, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or said Formula (D-1) - The solvent represented by the said Formula (D-3) can be used.

A solvent may be used independently and may be mixed and used for it. Furthermore, even if it is a solvent in which a polyimide precursor is not dissolved, you may use it in the range in which the produced|generated polyimide precursor does not precipitate, mixing with the said solvent. Moreover, since the water|moisture content in a solvent inhibits a polymerization reaction and becomes a cause to hydrolyze the produced|generated polyimide precursor by extension, it is preferable to use the thing which dehydrated and dried the solvent.

The solvent used for the above reaction is preferably N,N-dimethylformamide, N-methyl-2-pyrrolidone, or γ-butyrolactone from the viewpoint of polymer solubility, and these are one type or two or more types. may be mixed and used. The concentration at the time of production is preferably from 1% by mass to 30% by mass, more preferably from 5% by mass to 20% by mass, from the viewpoints that polymer precipitation hardly occurs and high molecular weight is easily obtained.

[2] When prepared by reaction of tetracarboxylic acid diester dichloride with diamine

Polyamic acid ester can be manufactured from the diamine component containing tetracarboxylic-acid diester dichloride and the diamine of this invention.

Specifically, tetracarboxylic-acid diester dichloride and diamine are -20 degreeC - 150 degreeC in presence of a base and an organic solvent, Preferably it is 0 degreeC - 50 degreeC WHEREIN: 30 minutes - 24 hours, Preferably It can manufacture by making it react for 1 hour - 4 hours.

As the base, although pyridine, triethylamine, 4-dimethylaminopyridine, etc. can be used, pyridine is preferable in order for the reaction to proceed mildly. The addition amount of the base is a quantity that can be easily removed, and is preferably 2 to 4 moles, more preferably 2 to 3 moles, with respect to tetracarboxylic acid diester dichloride, from the viewpoint of being easy to obtain a high molecular weight product. Do.

The solvent used for the above reaction is preferably N-methyl-2-pyrrolidone or γ-butyrolactone from the viewpoint of monomer and polymer solubility, and these may be used alone or in mixture of two or more. .

1 mass % - 30 mass % are preferable, and, as for the polymer density|concentration at the time of manufacture, from the point which polymer precipitation does not occur easily and a high molecular weight body is easy to obtain, 5 mass % - 20 mass % are more preferable.

Moreover, in order to prevent hydrolysis of tetracarboxylic acid diester dichloride, it is preferable that the solvent used for manufacture of polyamic acid ester is dehydrated as much as possible, and it is preferable to prevent mixing of external air in nitrogen atmosphere. .

[3] When prepared from tetracarboxylic acid diester and diamine

Polyamic acid ester can be manufactured by polycondensing the diamine component containing tetracarboxylic-acid diester and the diamine of this invention.

Specifically, tetracarboxylic-acid diester and diamine are 0 degreeC - 150 degreeC in presence of a condensing agent, a base, and an organic solvent, Preferably 0 degreeC - 100 degreeC WHEREIN: 30 minutes - 24 hours, Preferably can be produced by reacting for 3 to 15 hours.

Examples of the condensing agent include triphenylphosphite, dicyclohexylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, N,N'-carbonyldiimidazole, dimethoxy-1, 3,5-triazinylmethylmorpholinium, O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate, O-(benzotriazole-1 -yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate, (2,3-dihydro-2-thioxo-3-benzooxazolyl)phosphonic acid diphenyl, etc. can be used. there is. 2 times mole - 3 times mole are preferable with respect to tetracarboxylic-acid diester, and, as for the addition amount of a condensing agent, 2 times mole - 2.5 times mole are more preferable.

As the base, tertiary amines such as pyridine and triethylamine can be used. The addition amount of the base is an easy-to-remove amount, and from the viewpoint of easily obtaining a high molecular weight substance, 2 moles to 4 moles are preferable, and more preferably 2.5 times moles to 3.5 times moles relative to the diamine component.

Moreover, in the said reaction, reaction advances efficiently by adding a Lewis acid as an additive. As a Lewis acid, lithium halides, such as lithium chloride and lithium bromide, are preferable. 0 times mole - 1.0 times mole are preferable with respect to a diamine component, and, as for the addition amount of a Lewis acid, 0 times mole - 0.7 times mole are more preferable.

Since high molecular weight polyamic acid ester is obtained among the manufacturing methods of said three polyamic acid ester, the manufacturing method of said [1] or said [2] is especially preferable.

A polymer can be deposited by injecting|pouring into a poor solvent, stirring well the solution of polyamic acid ester obtained by making it above. After performing precipitation for several times and wash|cleaning with a poor solvent, it can make room temperature or heat-dry, and can obtain the refined powder of polyamic acid ester. Although the poor solvent is not specifically limited, Water, methanol, ethanol, hexane, a butyl cellosolve, acetone, toluene, etc. are mentioned.

<Manufacturing method of polyimide>

The polyimide used for this invention can be manufactured by imidating the said polyimide precursor.

The polyimide of this invention WHEREIN: The ring closure rate (imidization rate) of an amic acid group or an amic acid ester group does not necessarily need to be 100 %, What is necessary is just to adjust arbitrarily according to a use and the objective.

As a method of ring-closing a polyimide precursor, the thermal imidation which heats a polyimide precursor without using a catalyst, and catalyst imidation using a catalyst are mentioned.

When thermally imidating a polyimide precursor, the solution of a polyimide precursor is 100 degreeC - 400 degreeC, Preferably it is 120 degreeC - 250 degreeC, and removes water or alcohol produced|generated by imidation reaction to the outside of a system. It is preferable to do it while

Catalyst imidation of a polyimide precursor is -20 degreeC - 250 degreeC by adding a basic catalyst and an acid anhydride to the solution of a polyamic acid, Preferably it can perform by stirring at 0 degreeC - 180 degreeC. The amount of the basic catalyst is 0.5 to 30 mole times of the amic acid group, preferably 2 to 20 mole times, and the amount of the acid anhydride is 1 to 50 mole times of the amic acid group, preferably 3 to 30 mole times.

Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine, and among them, pyridine is preferable because it has suitable basicity to advance the reaction.

Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride, and among these, use of acetic anhydride is preferable because purification after completion of the reaction becomes easy. The imidation rate by catalytic imidation can be controlled by adjusting the catalyst amount, reaction temperature, and reaction time.

When recovering a polymer component from the reaction solution of polyimide, what is necessary is just to inject|throw-in the reaction solution to a poor solvent and just to precipitate. Examples of the poor solvent used for precipitation include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and water. It is preferable to dry the polymer which was injected|thrown-in to the poor solvent and precipitated, after filtering and collect|recovering it, under normal pressure or reduced pressure, normal temperature or heating.

<Liquid crystal aligning agent>

A liquid crystal aligning agent is a coating liquid for producing a liquid crystal aligning film, The main component is a composition containing the resin component for forming a resin film, and the organic solvent in which this resin component is dissolved. For the liquid crystal aligning agent of this invention, the at least 1 sort(s) of polymer chosen from the group which consists of polyimide obtained by ring-closing an above-described polyimide precursor and this polyimide precursor is used as a resin component.

The density|concentration of the polymer in a liquid crystal aligning agent can be suitably changed with setting of the thickness of the coating film which you want to form. It is preferable that it is 1 mass % or more from the point of forming a uniform and defect-free coating film, and it is preferable to set it as 10 mass % or less from the point of storage stability of a solution. A particularly preferable concentration of the polymer is 2% by mass to 8% by mass.

The whole polymer of this invention may be sufficient as the resin component in a liquid crystal aligning agent, and other polymers other than the polymer of this invention may be mixed. As such another polymer, the polyimide precursor or polyimide obtained using diamines other than what is represented by said Formula (1) as a diamine component is mentioned.

The organic solvent contained in a liquid crystal aligning agent will not be specifically limited if a polymer component melt|dissolves uniformly. Specific examples thereof include N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone Don, N-methylcaprolactam, 2-pyrrolidone, N-vinyl-2-pyrrolidone, dimethyl sulfoxide, dimethyl sulfone, γ-butyrolactone, 1,3-dimethyl-imidazolidinone, 3- and methoxy-N,N-dimethylpropanamide. You may use these 1 type or in mixture of 2 or more types. Moreover, even if it is a solvent which cannot melt|dissolve a polymer component uniformly independently, if it is a range in which a polymer does not precipitate, you may mix with said organic solvent.

A liquid crystal aligning agent may contain the solvent for improving the coating-film uniformity at the time of apply|coating a liquid crystal aligning agent to a board|substrate other than the organic solvent for melt|dissolving a polymer component. As such a solvent, a solvent having a lower surface tension than the organic solvent is generally used. Specific examples thereof include ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, ethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 2-butoxy-1-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate; Propylene glycol-1-monoethyl ether-2-acetate, butyl cellosolve acetate, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, diacetone alcohol, diethylene glycol diethyl ether, 2,6 -Dimethyl-4-heptanol, diisobutylketone, 4-methoxy-4-methyl-2-pentanone, 4-hydroxy-2-butanone and 2-methyl-2-hexanol, 2- (2 -ethoxypropoxy)propanol, lactic acid methyl ester, lactic acid ethyl ester, lactic acid n-propyl ester, lactic acid n-butyl ester, lactic acid isoamyl ester, etc. are mentioned. These solvents may use 2 or more types together.

The said solvent turns into a poor solvent with low solubility of resin. It is preferable that these solvents are 5 mass % - 60 mass % of the organic solvent contained in a liquid-crystal aligning agent, More preferably, they are 10 mass % - 50 mass %.

In the liquid crystal aligning agent, as long as the effect of this invention is not impaired other than the above, as long as it is a range in which the effect of this invention is not impaired, polymers other than the polymer of this invention, the dielectric or electrically-conductive material for the purpose of changing electrical characteristics, such as dielectric constant and electroconductivity of a liquid crystal aligning film, a liquid crystal aligning film, and A silane coupling agent for the purpose of improving the adhesiveness of the substrate, a crosslinking compound for the purpose of increasing the hardness and density of the film when a liquid crystal aligning film is used, and furthermore, when firing the coating film, imidization of the polyimide precursor efficiently proceeds You may add the target imidation accelerator etc.

When a crosslinkable compound such as a functional silane-containing compound or an epoxy group-containing compound is contained, the amount thereof is preferably 0.1 parts by mass to 30 parts by mass, more preferably 1 part by mass to 20 parts by mass relative to 100 parts by mass of the resin component. It is a mass part, Especially preferably, they are 1 mass part - 10 mass parts.

<Method for Producing Liquid Crystal Alignment Film>

A liquid crystal aligning film is a film|membrane obtained by apply|coating the said liquid crystal aligning agent to a board|substrate, drying and baking.

It will not specifically limit if it is a board|substrate with high transparency as a board|substrate which apply|coats a liquid crystal aligning agent, Plastic substrates, such as a glass substrate, a silicon nitride board|substrate, an acryl board|substrate, a polycarbonate board|substrate, etc. can be used. In particular, it is preferable from a viewpoint of process simplification to use the board|substrate with which the ITO electrode etc. for liquid crystal drive were formed.

Moreover, in a reflective liquid crystal display element, if it is only one side board|substrate, even if it is opaque, such as a silicon wafer, it can be used, and a material which reflects light, such as aluminum, can also be used for the electrode in this case.

As a coating method of a liquid crystal aligning agent, the spin coating method, the printing method, the inkjet method, etc. are mentioned. In addition, as a method of using a coating liquid, there exist a dip, a roll coater, a slit coater, a spinner, etc., You may use these according to the objective.

Drying after apply|coating a liquid crystal aligning agent, and a baking process can select arbitrary temperature and time. Usually, in order to sufficiently remove the contained organic solvent, it is dried at 50°C to 120°C, preferably at 50°C to 80°C, for 1 minute to 10 minutes, preferably for 3 minutes to 5 minutes, and then, It is 150 degreeC - 300 degreeC, Preferably it is 200 degreeC - 240 degreeC, 5 minutes - 120 minutes, Preferably it bakes in 10 minutes - 40 minutes.

Although the thickness of the coating film after baking is not specifically limited, Since reliability of a liquid crystal display element may fall when it is too thin, 5 nm - 300 nm, Preferably they are 10 nm - 200 nm.

As a method of orientating the obtained liquid crystal aligning film, the rubbing method, the photo-alignment processing method, etc. are mentioned. A rayon cloth, nylon cloth, cotton cloth, etc. can be used for a rubbing process. Since it is difficult for the liquid crystal aligning film for vertical alignment to obtain a uniform orientation state by a rubbing process, when using it as a liquid crystal aligning agent for vertical alignment, it can also be used, without rubbing.

As a specific example of the photo-alignment treatment method, the coating film surface is irradiated with radiation polarized in a certain direction, and in some cases, further heat-treated at a temperature of 150 ° C. to 250 ° C. to impart liquid crystal alignment ability. how to do it As the radiation, ultraviolet rays and visible rays having a wavelength of 100 nm to 800 nm can be used. Among these, the ultraviolet-ray which has a wavelength of 100 nm - 400 nm is preferable, and what has a wavelength of 200 nm - 400 nm is especially preferable.

Moreover, in order to improve liquid-crystal orientation, you may irradiate a radiation, heating a coating-film board|substrate at 50 degreeC - 250 degreeC.

The radiation dose is preferably 1 mJ/cm 2 to 10,000 mJ/cm 2 , and particularly preferably 100 mJ/cm 2 to 5,000 mJ/cm 2 . The liquid crystal aligning film produced as mentioned above can orientate a liquid crystal molecule stably in a fixed direction.

As mentioned above, you may contact-process the film|membrane which irradiated the polarized radiation with the solvent containing at least 1 type selected from water and organic solvent next.

The solvent used for the contact treatment is not particularly limited as long as it dissolves the decomposed product produced by light 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, methyl lactate. , diacetone alcohol, 3-methoxy methyl propionate, 3-ethoxy ethyl propionate, propyl acetate, butyl acetate, cyclohexyl acetate, etc. are mentioned. These solvents may use 2 or more types together.

From the viewpoint of versatility and safety, at least one selected from the group consisting of water, 2-propanol, 1-methoxy-2-propanol and ethyl lactate is more preferable. Particular preference is given to 1-methoxy-2-propanol or ethyl lactate.

In the present invention, the contact treatment of the film irradiated with polarized radiation and the solution containing the organic solvent is preferably performed by a treatment in which the film and the liquid are sufficiently contacted, such as immersion treatment and spraying (spray) treatment. Especially, the method of immersing a film|membrane in the solution containing an organic solvent, Preferably it is 10 second - 1 hour, More preferably, it is 1 minute - 30 minutes is preferable. Although normal temperature or heating may be sufficient as a contact process, Preferably it is 10 degreeC - 80 degreeC, More preferably, it is 20 degreeC - 50 degreeC. Moreover, if necessary, a means for increasing the contact such as ultrasonic waves can be provided.

After the contact treatment, either one or both of rinsing (rinsing) and drying with a low-boiling solvent such as water, methanol, ethanol, 2-propanol, acetone, and methyl ethyl ketone for the purpose of removing the organic solvent in the used solution. may be carried out.

In addition, you may heat the film|membrane which performed the contact process with the solvent at 150 degreeC or more for the purpose of drying the solvent and reorientation of the molecular chains in a film|membrane.

As heating temperature, 150 degreeC - 300 degreeC are preferable. A higher temperature promotes the reorientation of molecular chains, but an excessively high temperature may accompany decomposition of the molecular chains. Therefore, as heating temperature, 180 degreeC - 250 degreeC are more preferable, and 200 degreeC - 230 degreeC are especially preferable.

When the heating time is too short, the effect of the present invention may not be obtained, and if too long, the molecular chain may be decomposed. Therefore, 10 seconds to 30 minutes are preferable, and 1 minute to 10 minutes are more preferable.

<Liquid crystal display element>

After obtaining the board|substrate with a liquid crystal aligning film obtained from the liquid crystal aligning agent of this invention, a liquid crystal display element produces a liquid crystal cell by a known method, and sets it as a liquid crystal display element using the liquid crystal cell.

As an example of the manufacturing method of a liquid crystal cell, the liquid crystal display element of a passive matrix structure is taken as an example and demonstrated. Moreover, the liquid crystal display element of the active matrix structure in which switching elements, such as a TFT (Thin Film Transistor) was formed in each pixel part which comprises an image display may be sufficient.

First, a transparent glass substrate is prepared, a common electrode is formed on one substrate, and a segment electrode is formed on the other substrate. These electrodes can be, for example, ITO electrodes, and are patterned so that a desired image display can be performed. Next, an insulating film is formed on each substrate so as to cover the common electrode and the segment electrode. The insulating film can be, for example, a film made of SiO ₂ -TiO ₂ formed by a sol-gel method.

Next, on each board|substrate, the liquid crystal aligning film of this invention is formed. Next, the other board|substrate is superimposed on one board|substrate so that the mutual orientation film|membrane surfaces may oppose, and the periphery is adhere|attached with a sealing material. A spacer is usually mixed in the sealing material in order to control the board|substrate clearance gap. Moreover, it is preferable to spread|disperse the spacer for board|substrate gap|interval control also to the in-plane part which does not form a sealing material. An opening in which liquid crystal can be filled from the outside is formed in a part of the sealing material.

Next, a liquid crystal material is injected into the space surrounded by the two board|substrates and the sealing material through the opening part formed in the sealing material. After that, this opening is sealed with an adhesive. A vacuum injection method may be used for injection|pouring, and the method which utilized the capillary phenomenon in air|atmosphere may be used. Moreover, a liquid crystal can also be filled by dripping a liquid crystal after drawing a sealing material on a board|substrate, and bonding together under reduced pressure.

As the liquid crystal material, any of a positive liquid crystal material and a negative liquid crystal material may be used. Especially when voltage retention uses the negative liquid crystal material lower than the positive liquid crystal material, when the liquid crystal aligning film of this invention is used, it will be excellent in an afterimage characteristic.

Next, a polarizing plate is installed. Specifically, a pair of polarizing plates are affixed to the surface on the opposite side to the liquid crystal layer of two board|substrates. By passing through the above process, the liquid crystal display element of this invention is obtained. Since this liquid crystal display element is using the liquid crystal aligning film obtained by the manufacturing method of the liquid crystal aligning film of this invention as a liquid crystal aligning film, it becomes the thing excellent in a residual image characteristic, and a high-definition multifunctional mobile phone (smartphone) and tablet type It becomes suitable for a PC, a liquid crystal television, etc.

Example

Examples are given below, and the present invention will be described in more detail. However, the present invention should not be construed as being limited to these Examples. The abbreviation of the compound used later and the measuring method of each characteristic are as follows.

<Abbreviation of compound>

In the following formulas DA-5 and DA-6, "Boc" is a tert-butoxycarbonyl group.

[Formula 42]

[Formula 43]

[Formula 44]

<Abbreviation of compound>

DA-7: 1,3-bis (4-aminophenethyl) urea

DA-8: 4-(2-methylaminoethyl)aniline

NMP: N-methyl-2-pyrrolidone

BCS : Butyl Cellosolve

GBL: γ-butyrolactone

<Viscosity>

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

<Production of liquid crystal display element>

First, a board|substrate with an electrode was prepared. The substrate is a glass substrate having a size of 30 mm × 35 mm and a thickness of 0.7 mm. On the board|substrate, the IZO electrode provided with the solid-shaped pattern which comprises a counter electrode as a 1st layer is formed. On the counter electrode of the first layer, as the second layer, a SiN (silicon nitride) film formed by the CVD method is formed. The film thickness of the SiN film of the second layer is 500 nm, and functions as an interlayer insulating film. On the SiN film of the 2nd layer, the comb-tooth-shaped pixel electrode formed by patterning the IZO film|membrane as 3rd layer is arrange|positioned, and two pixels of a 1st pixel and a 2nd pixel are formed. The size of each pixel is 10 mm long and about 5 mm wide. At this time, the counter electrode of the first layer and the pixel electrode of the third layer are electrically insulated by the action of the SiN film of the second layer.

The pixel electrode of the 3rd layer has the comb-tooth-shaped shape comprised by arranging two or more "<"-shaped electrode elements in which the center part was bent. The width in the width direction of each electrode element is 3 µm, and the distance between the electrode elements is 6 µm. Since the pixel electrode forming each pixel is constituted by arranging a plurality of bent U-shaped electrode elements in the central portion, the shape of each pixel is not a rectangular shape, but a thick, curved shape at the center like the electrode element. It has a shape resembling the letter 'K'. And each pixel is divided|segmented up and down with the bent part in the center as a boundary, and has a 1st area|region above a bending part, and a 2nd area|region below.

Comparing the 1st area|region and 2nd area|region of each pixel, the formation direction of the electrode element of the pixel electrode which comprises them differs. That is, based on the rubbing direction of the liquid crystal alignment layer to be described later, in the first area of the pixel, the electrode element of the pixel electrode is formed to form an angle (clockwise) of +10°, and in the second area of the pixel, the pixel electrode The electrode elements are formed to form an angle of -10° (counterclockwise). That is, in the first region and the second region of each pixel, the directions of the rotational operation (in-plane switching) in the substrate plane of the liquid crystal caused by the voltage application between the pixel electrode and the counter electrode are opposite to each other. Consists of.

Next, after filtering the obtained liquid crystal aligning agent with a 1.0-micrometer filter, the ITO film|membrane is formed into a film on the back surface as the said board|substrate with an electrode and a counter board|substrate which were prepared, and also spin on each of the glass substrates which have columnar spacer of 4 micrometers in height. Coated. Subsequently, after drying for 5 minutes on an 80 degreeC hotplate, it baked at 230 degreeC for 20 minutes, and obtained the polyimide film on each board|substrate as a 60-nm-thick coating film. After rubbing (roll diameter 120 mm, rotation speed 500 rpm, movement speed 30 mm/sec, press-in amount 0.3 mm) on this polyimide film|membrane with a rayon cloth in a predetermined rubbing direction, ultrasonic irradiation for 1 minute in pure water and dried at 80 °C for 10 minutes.

Then, using the two types of substrates with the liquid crystal aligning film, the respective rubbing directions were combined so as to be antiparallel, and the liquid crystal injection port was left and the periphery was sealed to prepare an empty cell having a cell gap of 3.8 µm. After vacuum-injecting liquid crystal (MLC-2041, manufactured by Merck Corporation) into this empty cell at room temperature, the injection port was sealed and it was set as the liquid crystal cell of antiparallel orientation. The obtained liquid crystal cell comprises an FFS mode liquid crystal display element. Then, after heating the obtained liquid crystal cell at 120 degreeC for 1 hour and leaving it to stand overnight, it was used for each evaluation.

<Evaluation of the relaxation characteristics of the accumulated charge>

The residual image was evaluated using the following optical systems. The prepared liquid crystal cell was installed between two polarizing plates arranged so that the polarization axes were orthogonal to each other, the LED backlight was turned on in a state where no voltage was applied, and the arrangement angle of the liquid crystal cell was adjusted so that the luminance of the transmitted light was the smallest.

Next, the V-T curve (voltage-transmittance curve) was measured, applying the alternating voltage of frequency 30Hz to this liquid crystal cell, and relative transmittance computed the alternating voltage used as 23 % as a drive voltage.

In residual image evaluation, a 1V DC voltage was simultaneously applied and it was made to drive for 40 minutes, applying the alternating voltage of 30 Hz of frequency used as 23 %, and a relative transmittance driving a liquid crystal cell. Thereafter, the applied DC voltage value was set to 0 V, only the application of the DC voltage was stopped, and the drive was further performed in that state for 15 minutes.

Evaluation evaluated by defining as "good|favorableness", when the relative transmittance|permeability fell to 25 % or less until 45 minutes passed from the time when application of a DC voltage was started. When 45 minutes or more were required until the relative transmittance|permeability falls to 25 % or less, it defined and evaluated as "defect".

And the residual image evaluation by the method mentioned above was performed on the temperature condition of the state whose temperature of a liquid crystal cell is 23 degreeC.

<Stability evaluation of liquid crystal orientation>

Using this liquid crystal cell, the alternating voltage of 10VPP was applied by the frequency 30Hz in a 60 degreeC constant temperature environment for 168 hours. Then, it was set as the state which short-circuited between the pixel electrode of a liquid crystal cell, and a counter electrode, and it was left to stand at room temperature as it is for 1 day.

After standing, the liquid crystal cell was installed between two polarizing plates arranged so that the polarization axes were orthogonal to each other, the backlight was turned on in a state where no voltage was applied, and the arrangement angle of the liquid crystal cell was adjusted so that the luminance of the transmitted light was the smallest. And the rotation angle at the time of rotating the liquid crystal cell from the angle at which the 2nd area|region of a 1st pixel becomes the darkest to the angle at which the 1st area|region becomes the darkest was computed as angle (DELTA). Similarly, in the second pixel, the second region and the first region were compared to calculate the same angle Δ. And the average value of the angle (DELTA) value of a 1st pixel and a 2nd pixel was computed as angle (DELTA) of a liquid crystal cell. When the value of angle (DELTA) of this liquid crystal cell exceeded 0.1 degree|times, it defined and evaluated as "defect". When the value of angle (DELTA) of this liquid crystal cell did not exceed 0.1 degree|times, it defined as "good|favorableness" and evaluated.

<Evaluation of BL tolerance>

The produced liquid crystal cell was aged for 1 week on 2000 nit BL. After aging, a voltage of 1 V was applied to the cell at a temperature of 60°C for 60 µsec, and the voltage after 100 msec was measured to evaluate the voltage retention.

At that time, when the voltage retention maintained 80% or more, it was defined as "good", and when it was less than 80%, it was defined and evaluated as "poor".

<Evaluation of rubbing resistance>

After apply|coating a liquid crystal aligning agent to an ITO board|substrate and drying it temporarily, it baked in 230 degreeC IR type oven and obtained the board|substrate with a liquid crystal aligning film. This liquid crystal aligning film was rubbed with rayon cloth (Roller rotation speed: 1000 rpm, stage movement speed: 20 mm/sec, press-fit length: 0.4 mm). This board|substrate was observed with the microscope, the thing in which the stripe by rubbing was not seen on the film surface was made into "good|favorableness", and the thing in which the stripe was seen was evaluated as "poor".

<Synthesis example>

(Synthesis Example 1)

34.36 g (0.12 mol) of DA-3 was added to a 500 ml flask equipped with a stirring device and a nitrogen inlet tube, and then 335.12 g of NMP was added thereto, followed by stirring to dissolve. 22.77 g (0.10 mol) of CA-1 was added, stirring this solution under water cooling, 83.80 g of NMPs were further added, and it stirred at 50 degreeC for 12 hours, and obtained the polyamic-acid solution (PAA-1).

(Synthesis Example 2)

25.20 g (0.088 mol) of DA-3 and 8.77 g (0.022 mol) of DA-6 were added to a 500 ml flask equipped with a stirring device and a nitrogen inlet tube, and then 333.97 g of NMP was added and stirred to dissolve it. . While stirring this solution under water cooling, CA-1 was added 22.96g (0.11 mol), 326g of NMPs were further added, and it stirred at 50 degreeC for 12 hours, and obtained the polyamic-acid solution (PAA-2).

(Synthesis Example 3)

25.20 g (0.088 mol) of DA-3 and 8.72 g (0.022 mol) of DA-5 were added to a 500 ml flask equipped with a stirring device and a nitrogen inlet tube, and then 334.28 g of NMP was added and stirred to dissolve . 23.06 g (0.11 mol) of CA-1 was added, stirring this solution under water cooling, 83.57 g of NMPs were further added, and it stirred at 50 degreeC for 12 hours, and obtained the polyamic-acid solution (PAA-3).

(Synthesis Example 4)

After 19.13 g (0.096 mol) of DA-4 was put into a 500 ml flask equipped with a stirring device and a nitrogen inlet tube, 232.72 g of a solvent (NMP:GBL=50 wt%: 50 wt%) was added and dissolved by stirring. made it After adding 14.12g (0.072 mol) of CA-2 and further adding 84.63g of solvents (NMP:GBL=50wt%:50wt%), stirring this solution under water cooling, it stirred for 2 hours. Then, after adding 4.76 g (0.024 mol) of DA-1, 42.31 g of NMP was added thereto, followed by stirring to dissolve. Further stirring under water cooling, 9.00 g (0.03 mol) of CA-3 is added, 326 g of solvents (NMP:GBL=50 wt%: 50 wt%) are further added, and the polyamic acid solution (PAA) is stirred for 2 hours. -4) was obtained.

(Synthesis Example 5)

In a 500 ml flask equipped with a stirring device and a nitrogen inlet tube, 23.91 g (0.12 mol) of DA-4 and 5.95 g (0.03 mol) of DA-1 were added, and then 255.76 g of NMP was added and stirred to dissolve. . After adding 6.47 g (0.033 mol) of CA-2 and further adding 73.01 g of NMP, stirring this solution under water cooling, it stirred for 2 hours. After that, after injecting 28.15g (0.11mol) of CA-4, 36.54g of NMPs were added, and it stirred at 50 degreeC for 12 hours, and obtained the polyamic-acid solution (PAA-5).

(Synthesis Example 6)

23.91 g (0.12 mol) of DA-4 and 4.56 g (0.03 mol) of DA-2 were added to a 500 ml flask equipped with a stirring device and a nitrogen inlet tube, and then 241.76 g of NMP was added and stirred to dissolve . After 13.71 g (0.070 mol) of CA-2 was added and further 69.07 g of NMP was added, stirring this solution under water cooling, it stirred for 2 hours. After 18.77 g (0.075 mol) of CA-4 was injected|thrown-in after that, 34.54g of NMPs were added, and it stirred at 50 degreeC for 12 hours, and obtained the polyamic-acid solution (PAA-6).

(Synthesis Example 7)

28.69 g (0.144 mol) of DA-4 and 7.14 g (0.036 mol) of DA-1 were added to a 500 ml flask equipped with a stirring device and a nitrogen inlet tube, and then 296.56 g of NMP was added and stirred to dissolve. . After adding 16.41g (0.084mol) of CA-2 and further adding 84.73g of NMPs, stirring this solution under water cooling, it stirred for 2 hours. After 22.52g (0.09mol) of CA-4 was injected|thrown-in after that, 42.37g of NMPs were added, and it stirred at 50 degreeC for 12 hours, and obtained the polyamic-acid solution (PAA-7).

(Synthesis Example 8)

In a 500 ml flask equipped with a stirring device and a nitrogen inlet tube, 18.98 g (0.048 mol) of DA-5 and 14.28 g (0.048 mol) of DA-7 were added, and then 312.67 g of NMP was added and stirred to dissolve it. . After 20.04 g (0.092 mol) of CA-1 was added and further 78.17 g of NMP was added, stirring this solution under water cooling, it stirred at 50 degreeC for 12 hours, and the polyamic-acid solution (PAA-8) was obtained.

(Synthesis Example 9)

In a 500 ml flask equipped with a stirring device and a nitrogen inlet tube, 26.85 g (0.09 mol) of DA-7 and 9.01 g (0.06 mol) of DA-8 were added, and then 289.28 g of NMP was added and stirred to dissolve. . After adding 27.94g (0.14mol) of CA-2 and further adding 72.32g of NMPs, stirring this solution under water cooling, it stirred for 2 hours and the polyamic-acid solution (PAA-9) was obtained.

(Comparative Example 1)

GBL solution containing 1.51 g of PAA-1 and 6.99 g of PAA-4, 3.13 g of NMP, 3.13 g of GBL, 6.00 g of BCS, and 1% by weight of AD-1 in a 20 ml sample tube containing a stirrer. 0.86g was added, and it stirred for 30 minutes with a magnetic stirrer, and obtained the liquid crystal aligning agent (A-1).

(Comparative Example 2)

GBL solution containing 1.33 g of PAA-1 and 4.27 g of PAA-5, 4.40 g of NMP, 5.36 g of GBL, 4.00 g of BCS, and 1 wt% of AD-1 in a 20 ml sample tube containing a stirrer. 0.64 g of was added, and it stirred for 30 minutes with a magnetic stirrer, and obtained the liquid crystal aligning agent (A-2).

(Comparative Example 3)

GBL solution containing 1.33 g of PAA-2 and 4.27 g of PAA-6, 4.40 g of NMP, 5.36 g of GBL, 4.00 g of BCS, and 1 wt% of AD-2 in a 20 ml sample tube containing a stirrer. 0.64g was added, and it stirred for 30 minutes with a magnetic stirrer, and obtained the liquid crystal aligning agent (A-3).

(Comparative Example 4)

GBL solution containing 2.00 g of PAA-8 and 6.40 g of PAA-9, 1.60 g of NMP, 5.04 g of GBL, 4.00 g of BCS, and 1 wt% of AD-2 in a 20 ml sample tube containing a stirrer. 0.96 g of was added, and it stirred for 30 minutes with a magnetic stirrer, and obtained the liquid crystal aligning agent (A-4).

(Example 1)

A GBL solution containing 1.33 g of PAA-3 and 4.27 g of PAA-6, 4.40 g of NMP, 5.36 g of GBL, 4.00 g of BCS, and 1 wt% of AD-2 in a 20 ml sample tube containing a stirrer. 0.64g was added, and it stirred for 30 minutes with a magnetic stirrer, and obtained the liquid crystal aligning agent (B-1).

(Example 2)

GBL solution containing 1.33 g of PAA-3 and 4.27 g of PAA-6, 4.16 g of NMP, 5.36 g of GBL, 4.00 g of BCS, and 1 wt% of AD-2 in a 20 ml sample tube containing a stirrer. 0.24 g of NMP solution containing 0.64 g and AD-3 of 10 weight% was added, it stirred for 30 minutes with a magnetic stirrer, and the liquid crystal aligning agent (B-2) was obtained.

(Example 3)

GBL solution containing 1.33 g of PAA-3 and 4.27 g of PAA-7, 4.40 g of NMP, 5.36 g of GBL, 4.00 g of BCS, and 1 wt% of AD-2 in a 20 ml sample tube containing a stirrer. 0.64g was added, and it stirred for 30 minutes with a magnetic stirrer, and obtained the liquid crystal aligning agent (B-3).

(Example 4)

GBL solution containing 1.33 g of PAA-3 and 4.27 g of PAA-7, 4.16 g of NMP, 5.36 g of GBL, 4.00 g of BCS, and 1 wt% of AD-2 in a 20 ml sample tube containing a stirrer. 0.24 g of NMP solution containing 0.64 g and AD-3 of 10 weight% was added, it stirred for 30 minutes with a magnetic stirrer, and the liquid crystal aligning agent (B-4) was obtained. Using the liquid crystal aligning agent obtained above, BL tolerance, the relaxation characteristic of an accumulated electric charge, stability of the liquid-crystal orientation, and rubbing tolerance evaluation were performed. The results are shown in Table 1 below.

As mentioned above, the liquid crystal aligning film of this invention showed the favorable result also in rubbing tolerance, BL tolerance evaluation, stability evaluation of a liquid crystal orientation, and evaluation of afterimage disappearance time.

Claims (8)

The liquid crystal aligning agent containing following (A) component and (B) component.
(A) component: at least selected from the group consisting of a polyimide precursor obtained by reacting a diamine component containing a diamine of the following formula (1) with a tetracarboxylic acid derivative component, and a polyimide obtained by ring closure of the polyimide precursor 1 type of polymer

(In formula (1), R ₁ represents hydrogen or a monovalent organic group. Q ₁ represents alkylene having 1 to 5 carbon atoms. Cy represents azetidine, pyrrolidine, piperidine or hexamethyleneimine. It is a divalent group representing an aliphatic heterocyclic ring, and a substituent may be bound to these ring moieties.R ₂ and R ₃ are each independently a monovalent organic group. q and r are each independently 0 to 4 It is an integer, provided that, when the sum of q and r is 2 or more, a plurality of R ₂ and R ₃ have the above definition.)
(B) component: a compound having two or more partial structures represented by the following formula (2) and having a molecular weight of 2,500 or less

(in formula (2), R ¹ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ² and R ³ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or * ³ -CH ₂ -OR ¹¹ (R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, "* ³ " represents a bond with the carbon atom to which R ² and R ³ are bonded.), "* ¹ " and "* ² " indicates that it is a bond with another atom.) The method of claim 1,
The liquid crystal aligning agent in which diamine of said Formula (1) is represented by following formula (3).

(In formula (3), R ₁ is a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group, R ₂ and R ₃ are each independently a hydrogen atom or a methyl group, and Q ₁ is a C 1 to C 5 group straight chain alkylene.) The method of claim 1,
The liquid crystal aligning agent whose content rate of the diamine represented by said Formula (1) is 1 mol% - 80 mol% with respect to 1 mol of all the diamine components. The method of claim 1,
The liquid crystal aligning agent whose compound of the said (B) component is an at least 1 sort(s) of compound chosen from a following formula.

The method of claim 1,
Furthermore, the liquid crystal aligning agent containing the polyimide precursor containing the structural unit of following formula (5) as (C)component.

(In formula (5), X ₂ is a tetravalent organic group derived from a tetracarboxylic acid derivative, Y ₂ is a divalent organic group derived from diamine, and R ₄ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; , Z ₁ and Z ₂ are each independently a hydrogen atom, an optionally substituted C1-C10 alkyl group, a C2-C10 alkenyl group, or a C2-C10 alkynyl group.) 6. The method of claim 5,
The liquid crystal aligning agent in which X< ₂ > in said Formula (5) contains the polyimide precursor containing the structural unit which is the following structure.

The liquid crystal aligning film obtained from the liquid crystal aligning agent in any one of Claims 1-6. A liquid crystal display element provided with the liquid crystal aligning film of Claim 7.