CN105940343B

CN105940343B - Aligning agent for liquid crystal and the liquid crystal expression element for having used it

Info

Publication number: CN105940343B
Application number: CN201480074334.1A
Authority: CN
Inventors: 新津新平; 高桥真文
Original assignee: Nissan Chemical Corp
Current assignee: Nissan Chemical Corp
Priority date: 2013-11-28
Filing date: 2014-11-27
Publication date: 2019-09-24
Anticipated expiration: 2034-11-27
Also published as: CN105940343A; KR102278975B1; TWI657099B; JPWO2015080186A1; KR20160090880A; JP6558543B2; WO2015080186A1; TW201538569A

Abstract

A kind of aligning agent for liquid crystal, it contains imide amination polymer obtained from polyimide precursor closed loop, the polyimide precursor has repetitive unit shown in formula (1), and at least part Y in formula (1) is the structure of following formula (2).In formula (1), Y is the divalent organic group from diamine component, and X is the 4 valence organic groups from tetracarboxylic acid derivatives, A¹And A²It is each independently the alkynyl of the alkyl of hydrogen atom or the optionally carbon number 1~10 with substituent group, the alkenyl of the optionally carbon number 2~10 with substituent group, the optionally carbon number 2~10 with substituent group, R¹For hydrogen atom or the alkyl of carbon number 1~10.

Description

Aligning agent for liquid crystal and the liquid crystal expression element for having used it

Technical field

The present invention relates to indicate the aligning agent for liquid crystal of element for manufacturing liquid crystal, taken by the liquid crystal that the aligning agent for liquid crystal obtains To film and the liquid crystal of the liquid crystal orientation film is used to indicate element.

Background technique

Liquid crystal expression element is as light weight, the expression device that volume is thin and power consumption is low is known.In recent years, towards city The high-resolution liquid crystal of mobile phone, panel type terminal that field occupation rate expands rapidly indicates that element also achieves the high expression quality journey of requirement The significant development of degree.

Liquid crystal indicates that element is constituted and having a pair of of transparent substrate of electrode and clamping liquid crystal layer.Also, liquid crystal Indicate element in, used as liquid crystal orientation film for make liquid crystal is presented between substrate it is expected state of orientation by organic material Expect the organic film formed.That is, liquid crystal orientation film is the component parts that liquid crystal indicates element, it is formed in the substrate of clamping liquid crystal The one side for contacting liquid crystal, plays the role of being orientated liquid crystal between the substrate along certain direction.In turn, it is taken by liquid crystal The pre-tilt angle of liquid crystal can be controlled to film.It is known that mainly improving the side of pre-tilt angle by selecting the structure of polyimides Method (referring to patent document 1) and the method (referring to patent document 2) for reducing pre-tilt angle etc..

Existing technical literature

Patent document

Patent document 1: Japanese Unexamined Patent Publication 09-278724 bulletin

Patent document 2: Japanese Unexamined Patent Publication 10-123532 bulletin

Summary of the invention

Problems to be solved by the invention

In recent years, liquid crystal is used to indicate element towards the mobile purposes such as smart phone, mobile phone.These on the way, in order to Ensure expression face as much as possible, the width of sealant used to make liquid crystal indicate to be bonded between the substrate of element It needs narrower than previous.In turn, it also requires to be set as the position of sealant close to the bonding Nian Jie with sealant due to the above reasons, The position of the end of the weak liquid crystal orientation film of property or the top for being set as liquid crystal orientation film.In this case, especially in height In use, water is easy to be mixed between sealant and liquid crystal orientation film under warm super-humid conditions, liquid crystal indicates the adjacent edges of element Occur to indicate uneven.

Thus, the object of the present invention is to provide can be improved the cementability of sealant and liquid crystal orientation film, inhibit high temperature Liquid crystal indicates that uneven aligning agent for liquid crystal occurs to indicate for the adjacent edges of element under super-humid conditions.

The solution to the problem

The inventors of the present invention have made intensive studies in order to solve the above problems, as a result complete the present invention.That is, of the invention Purport it is as follows.

1. a kind of aligning agent for liquid crystal, which is characterized in that it is containing selected from reacting diamine component with tetracarboxylic acid derivatives Obtained from polyimide precursor and the polyimide precursor is carried out obtained from imidizate in imide amination polymer At least one kind of aligning agent for liquid crystal, the polyimide precursor have repetitive unit shown in following formula (1).

In formula (1), Y is the divalent organic group from diamine component, and X is the 4 valence organic groups from tetracarboxylic acid derivatives Group, A¹And A²It is each independently the alkyl of hydrogen atom or the optionally carbon number 1~10 with substituent group, optionally there is substituent group Carbon number 2~10 alkenyl, optionally with substituent group carbon number 2~10 alkynyl, R¹For hydrogen atom or the alkane of carbon number 1~10 Base, at least part Y are the structure of following formula (2).

2. the aligning agent for liquid crystal according to above-mentioned 1, wherein in repetitive unit shown in above-mentioned formula (1), at least part X is the 4 valence organic groups with ester ring type structure or aliphatic structure.

3. the aligning agent for liquid crystal according to above-mentioned 2, wherein in repetitive unit shown in above-mentioned formula (1), at least part X is the structure in following (X-9), (X-26), (X-27).

4. the aligning agent for liquid crystal according to above-mentioned 2, wherein in repetitive unit shown in above-mentioned formula (1), X is with rouge The ratio of 4 valence organic groups of ring structures or aliphatic structure is 10~100 moles of %.

5. the aligning agent for liquid crystal according to above-mentioned 3, wherein in repetitive unit shown in above-mentioned formula (1), X be (X-9), (X-26), the ratio of the arbitrary structures in (X-27) is 10~100 moles of %.

6. the aligning agent for liquid crystal according to above-mentioned any one of 1~5, wherein repetitive unit shown in above-mentioned formula (1) In, Y is that the ratio of the structure of above-mentioned formula (2) is 10~100 moles of %.

7. a kind of liquid crystal orientation film is that aligning agent for liquid crystal described in above-mentioned any one of 1~6 is coated on substrate and is burnt Obtained from.

8. a kind of liquid crystal indicates element, with liquid crystal orientation film described in above-mentioned 7.

The effect of invention

By using aligning agent for liquid crystal of the invention, can obtain can be improved the cementability of sealant and liquid crystal orientation film, Liquid crystal under the conditions of high temperature and humidity is inhibited to indicate that uneven liquid crystal orientation film occurs to indicate for the adjacent edges of element.Therefore, have by The liquid crystal of this obtained liquid crystal orientation film indicates that element is able to solve by improving the cementability of sealant and liquid crystal orientation film The expression of adjacent edges is uneven, can be suitably employed in the liquid crystal display of big picture and high-resolution.

Specific embodiment

Aligning agent for liquid crystal of the invention is characterized in that, for containing selected from reacting diamine component with tetracarboxylic acid derivatives Obtained from polyimide precursor and the polyimide precursor is carried out obtained from imidizate in imide amination polymer At least one kind of aligning agent for liquid crystal, the polyimide precursor have repetitive unit shown in following formula (1).

Tetracarboxylic acid derivatives used in the present invention can enumerate tetracarboxylic dianhydride, tetrabasic carboxylic acid monoester anhydride, tetrabasic carboxylic acid, dicarboxyl Acid dialkyl ester, dicarboxylic acid chloride's dialkyl ester etc., as long as reacting with diamines, are not limited to them.

In formula (1), X is the 4 valence organic groups from tetracarboxylic acid derivatives, and structure is not particularly limited.If having to The concrete example of X is shown, then can enumerate X-1~X-44 described below.

In formula (X-1), R²~R⁵Each independently represent hydrogen atom, methyl or phenyl.

In formula (1), X can be a kind, can also be mixed two or more, since X has ester ring type structure or aliphatic Structure, cementability become higher, it is therefore preferable that including a kind or more of the X with ester ring type structure or aliphatic structure.As The preferred proportion of X with ester ring type structure or aliphatic structure is 10 moles of % or more of X entirety, more preferably 50 rubs You are % or more, further preferably 80 moles of % or more.

As the structure with ester ring type structure or the X of aliphatic structure, preferably (X-1)~(X-16), (X-23)~ (X-27), (X-41)~(X-43), from the viewpoint of it can obtain strong bonding force, particularly preferably (X-9), (X-26), (X- 27)。

In formula (1), as R¹In abovementioned alkyl concrete example, methyl, ethyl, propyl, isopropyl, positive fourth can be enumerated Base, isobutyl group, sec-butyl, tert-butyl, n-pentyl etc..

In formula (1), A¹And A²Be each independently hydrogen atom or optionally with substituent group carbon number 1~10 alkyl, The alkynyl of the alkenyl of the optional carbon number 2~10 with substituent group, the optional carbon number 2~10 with substituent group.

As the concrete example of abovementioned alkyl, methyl, ethyl, propyl, butyl, tert-butyl, hexyl, octyl, the last of the ten Heavenly stems can be enumerated Base, cyclopenta, cyclohexyl, dicyclohexyl etc..As alkenyl, can enumerate 1 or more CH-CH knot present in abovementioned alkyl Alkenyl obtained from changing C=C structure into is set up, more specifically, vinyl, allyl, 1- acrylic, isopropyl alkene can be enumerated Base, 2- cyclobutenyl, 1,3- butadienyl, 2- pentenyl, 2- hexenyl, cyclopropanyl, cyclopentenyl, cyclohexenyl group etc..As Alkynyl can be enumerated 1 or more CH present in aforesaid alkyl₂-CH₂Structure replacing is at alkynyl obtained from C ≡ C-structure, more Specifically, acetenyl, 1- propinyl, 2-propynyl etc. can be enumerated.

Abovementioned alkyl, alkenyl, alkynyl optionally have substituent group, in turn, can also form ring structure by substituent group.It needs It is noted that by substituent group formed ring structure refer to substituent group each other or substituent group is bonded with a part of female skeleton and Form ring structure.

Example as the substituent can enumerate halogen group, hydroxyl, mercapto, nitro, aryl, organic oxygroup, have Machine sulfenyl, Organosilyl, acyl group, ester group, thioester substrate, phosphate-based, amide groups, alkyl, alkenyl, alkynyl.

As the halogen group for belonging to substituent group, fluorine atom, chlorine atom, bromine atom, iodine atom can be enumerated.

As the aryl for belonging to substituent group, phenyl can be enumerated.The aryl, which can also replace, aforementioned other substituent groups.

As the organic oxygroup for belonging to substituent group, structure shown in O-R can be shown.The R can be the same or different, Aforesaid alkyl, alkenyl, alkynyl, aryl etc. can be exemplified.These R, which can also replace, foregoing substituents.As organic oxygroup Concrete example can enumerate methoxyl group, ethyoxyl, propoxyl group, butoxy, amoxy, hexyloxy, oxygroup in heptan, octyloxy etc..

As the organic sulfenyl for belonging to substituent group, structure shown in-S-R can be shown.As the R, can exemplify aforementioned Alkyl, alkenyl, alkynyl, aryl etc..These R, which can also replace, foregoing substituents.As the concrete example of organic sulfenyl, can enumerate Methyl mercapto, ethylmercapto group, rosickyite base, butylthio, penta sulfenyl, own sulfenyl, sulfenyl in heptan, pungent sulfenyl etc. out.

As the Organosilyl for belonging to substituent group ,-Si- (R) can be shown₃Shown in structure.The R can be identical Can be different, aforesaid alkyl, alkenyl, alkynyl, aryl etc. can be exemplified.These R, which can also replace, foregoing substituents.As having The concrete example of machine silicyl can enumerate trimethyl silyl, triethylsilyl, tripropylsilyl base, three fourths Base silicyl, three amyl silicyls, three hexyl silicyls, amyl dimethyl silicyl, hexyl dimethyl silane Base etc..

As the acyl group for belonging to substituent group, structure shown in-C (O)-R can be shown.As the R, aforementioned alkane can be exemplified Base, alkenyl, aryl etc..These R, which can also replace, foregoing substituents.As the concrete example of acyl group, formoxyl, second can be enumerated Acyl group, propiono, bytyry, isobutyryl, valeryl, isovaleryl, benzoyl etc..

As the ester group for belonging to substituent group, structure shown in-C (O) O-R or-OC (O)-R can be shown.It, can as the R Exemplify aforesaid alkyl, alkenyl, alkynyl, aryl etc..These R, which can also replace, foregoing substituents.

As the thioester substrate for belonging to substituent group, structure shown in-C (S) O-R or-OC (S)-R can be shown.As the R, Aforesaid alkyl, alkenyl, alkynyl, aryl etc. can be exemplified.These R, which can also replace, foregoing substituents.

As the phosphate-based of substituent group is belonged to ,-OP (O)-(OR) can be shown₂Shown in structure.The R can be identical Can be different, aforesaid alkyl, alkenyl, alkynyl, aryl etc. can be exemplified.These R, which can also replace, foregoing substituents.

As the amide groups for belonging to substituent group ,-C (O) NH can be shown₂Or-C (O) NHR ,-NHC (O) R ,-C (O) N (R)₂, structure shown in-NRC (O) R.The R can be the same or different, and can exemplify aforesaid alkyl, alkenyl, alkynyl, aryl Deng.These R, which can also replace, foregoing substituents.

As the aryl for belonging to substituent group, aryl identical with aforesaid aryl can be enumerated.The aryl, which can also replace, to be had Aforementioned other substituent groups.

As the alkyl for belonging to substituent group, alkyl identical with aforesaid alkyl can be enumerated.The alkyl, which can also replace, to be had Aforementioned other substituent groups.

As the alkenyl for belonging to substituent group, alkenyl identical with foregoing alkenyl can be enumerated.The alkenyl, which can also replace, to be had Aforementioned other substituent groups.

As the alkynyl for belonging to substituent group, alkynyl identical with aforementioned alkynyl can be enumerated.The alkynyl, which can also replace, to be had Aforementioned other substituent groups.

When being normally introduced into bulky structure, it is possible to the reactivity of amino, liquid crystal aligning are reduced, therefore, as A¹And A², the more preferably alkyl of hydrogen atom or the optionally carbon number 1~5 with substituent group, particularly preferably hydrogen atom, methyl Or ethyl.

In formula (1), at least part Y is the structure of formula (2).If having to show the ratio that Y is the structure of formula (2), 10 moles of %~100 mole % can be enumerated.In addition, 50 moles of % of Y are the above are when the structure of formula (2), bonding force becomes more Height, so it is preferred that, more preferably 70 moles of % or more, further preferably 90 moles of % or more.

As described above, Y is not limited to formula (2), it can also include other structures.If having to show other Y structures Concrete example can then enumerate following Y-1~Y-115.

(in formula (Y-102), m, n are respectively 1~11 integer, the integer that m+n is 2~12；In formula (Y-107), h be 1~ 3 integer；In formula (Y-104) and (Y-111), j be 0~3 integer.)

Among these, Y-7, Y-21, Y-22, Y-23, Y-25, Y-26, Y-27, Y-43, Y-44, Y-45, Y-46, Y-48, The linear high structure such as Y-56, Y-64, Y-66, Y-67, Y-68, Y-91, Y-92, Y-93, can when liquid crystal orientation film is made Improve the orientation of liquid crystal.In addition, such as Y-69, Y-70, Y-71, Y-72, Y-73, Y-74, Y-75, Y-76, Y-77, Y-78, Y- 79, like that, side chain has long-chain by Y-80, Y-81, Y-82, Y-83, Y-84, Y-85, Y-86, Y-87, Y-88, Y-89, Y-90 etc. Alkyl, aromatic ring, aliphatic ring, steroid skeleton or the structure for being composed them can when liquid crystal orientation film is made Improve the pre-tilt angle of liquid crystal.In addition, can to obtain good brushing when liquid crystal orientation film is made resistance to for structure as Y-111 Property.

Polyimide precursor used in the present invention be as obtained from the reacting of diamine component and tetracarboxylic acid derivatives, can Enumerate polyamic acid, poly amic acid ester etc..

Polyimide precursor, that is, polyamic acid used in the present invention can synthesize by the following method.

Specifically, can by make tetracarboxylic dianhydride and diamines in presence of organic solvent with -20 DEG C~150 DEG C, it is excellent Choosing reacts 30 minutes~24 hours, preferably 1~12 hour with 0 DEG C~50 DEG C to synthesize.

From the dissolubility of monomer and polymer, organic solvent used in above-mentioned reaction is preferably N, N- dimethyl methyl Amide, n-methyl-2-pyrrolidone, gamma-butyrolacton, they can be used a kind or are mixed with two or more.From polymer hardly possible From the perspective of being precipitated and be easy to get high molecular weight body, the concentration of polymer is preferably 1~30 mass %, and more preferably 5 ~20 mass %.

It is above-mentioned it is such operate obtained from polyamic acid it is bad molten by being injected into while reaction solution is sufficiently stirred In agent, polymer can be made to be precipitated and recycle.In addition, then being carried out normal by being precipitated and being cleaned with poor solvent for several times Warm drying or heat drying can obtain the powder of the polyamic acid through refining.Poor solvent is not particularly limited, and can enumerate Water, methanol, ethyl alcohol, hexane, butyl cellosolve, acetone, toluene etc..

Polyimide precursor, that is, poly amic acid ester used in the present invention can pass through method (1) shown below~(3) Lai Hecheng.

(1) when being synthesized by polyamic acid

Poly amic acid ester can be synthesized by the way that the polyamic acid obtained by tetracarboxylic dianhydride and diamines to be esterified.

Specifically, can by make polyamic acid and esterifying agent in presence of organic solvent with -20 DEG C~150 DEG C, It is preferred that 0 DEG C~50 DEG C are reacted 30 minutes~24 hours, preferably 1~4 hour to synthesize.

As esterifying agent, it is preferably capable the esterifying agent easily removed by purification, N, N- dimethyl methyl can be enumerated Amide dimethyl-acetal, N,N-dimethylformamide diethyl acetal, N,N-dimethylformamide dipropyl acetal, N, Dinethylformamide di neo-pentyl butyl acetal, N,N-dimethylformamide di-t-butyl acetal, 1- methyl -3- are to first Phenyl triazenes, 1- ethyl -3- p-methylphenyl triazenes, 1- propyl -3- p-methylphenyl triazenes, 4- (dimethoxy -1 4,6-, 3,5- triazine -2- base) -4- methylmorpholinium chloride etc..The additive amount of esterifying agent is excellent relative to 1 mole of repetitive unit of polyamic acid It is selected as 2~6 molar equivalents.

From the dissolubility of polymer, the solvent for above-mentioned reaction is preferably n,N-Dimethylformamide, N- methyl- 2-Pyrrolidone or gamma-butyrolacton, they can be used a kind or are mixed with two or more.Precipitation is difficult to happen from polymer And be easy to get from the perspective of high molecular weight body, concentration when synthesis is preferably 1~30 mass %, more preferably 5~20 matter Measure %.

(2) by tetracarboxylic acid acid diesters dichloride with diamines when reacting to synthesize

Poly amic acid ester can be synthesized by tetracarboxylic acid acid diesters dichloride and diamines.

Specifically, can by make tetracarboxylic acid acid diesters dichloride and diamines in the presence of alkali and organic solvent with- 20 DEG C~150 DEG C, preferably 0 DEG C~50 DEG C are reacted 30 minutes~24 hours, preferably 1~4 hour to synthesize.

Pyridine, triethylamine, 4-dimethylaminopyridine etc. can be used in aforementioned bases, in order to carry out reaction leniently, preferably For pyridine.It is subordinated to the amount easily removed and is easy to get from the perspective of high molecular weight body, the additive amount of alkali is relative to tetracarboxylic acid Acid diesters dichloride is preferably 2~4 times moles.

From the dissolubility of monomer and polymer, the solvent for above-mentioned reaction be preferably n-methyl-2-pyrrolidone, Gamma-butyrolacton, they can be used a kind or are mixed with two or more.Precipitation is difficult to happen from polymer and is easy to get height From the perspective of molecular weight body, polymer concentration when synthesis is preferably 1~30 mass %, more preferably 5~20 mass %.Separately Outside, tetracarboxylic acid acid diesters dichloride hydrolyzes in order to prevent, and the solvent for synthesizing polyamides acid esters is preferably taken off as far as possible Water, atmosphere is mixed into and it is preferred that carrying out in nitrogen atmosphere in order to prevent.

(3) when by dicarboxylic diester and diamines come synthesizing polyamides acid

Poly amic acid ester can be synthesized by the way that dicarboxylic diester is carried out polycondensation with diamines.

Specifically, can be by making dicarboxylic diester and diamines in the presence of condensing agent, alkali, organic solvent with 0 DEG C ~150 DEG C, preferably 0 DEG C~100 DEG C are reacted 30 minutes~24 hours, preferably 3~15 hours to synthesize.

Triphenyl phosphite, dicyclohexylcarbodiimide, 1- ethyl -3- (3- dimethylamino can be used in aforementioned condensation agent Propyl) carbodiimide hydrochloride, N, N '-carbonyl dimidazoles, dimethoxy-cyanuro 1,3,5 methyl morpholine, O- (benzo three Azoles -1- base)-N, N, N ', N '-tetramethylurea tetrafluoro boric acid ester, O- (benzotriazole -1- base)-N, N, N ', N '-tetramethylurea six Fluorophosphoric acid ester, diphenyl (2,3- dihydro -2- thia -3- benzoxazoles) phosphonate ester etc..The additive amount of condensing agent is relative to dicarboxyl Acid diesters are preferably 2~3 times moles.

The tertiary amines such as pyridine, triethylamine can be used in aforementioned bases.It is subordinated to the amount easily removed and is easy to get high molecular weight From the perspective of body, the additive amount of alkali is preferably 2~4 times moles relative to diamine component.

In addition, by addition lewis acid as additive, reaction can be effectively performed in above-mentioned reaction.As Louis This acid, the preferably halogenated lithium such as lithium chloride, lithium bromide.Lewis acidic additive amount is preferably 0~1.0 times relative to diamine component Mole.

Among the synthetic method of above-mentioned 3 kinds of poly amic acid esters, since the poly amic acid ester of high molecular weight can be obtained, because This, the synthetic method of particularly preferably above-mentioned (1) or above-mentioned (2).

It is above-mentioned it is such operate obtained from poly amic acid ester solution it is bad molten by being injected into while being sufficiently stirred In agent, polymer can be made to be precipitated.By being precipitated and being cleaned with poor solvent for several times, then carry out air drying or Heat drying can obtain the powder of the poly amic acid ester through refining.Poor solvent is not particularly limited, and can enumerate water outlet, first Alcohol, isopropanol, ethyl alcohol, hexane, butyl cellosolve, acetone, toluene etc..

Imide amination polymer used in the present invention can be made by the way that aforementioned polyimide precursor is carried out imidizate It makes.When manufacturing imide amination polymer by polyimide precursor, the change of basic catalyst is added into polyimide precursor solution It is easy for learning imidizate.Since imidization reaction carries out at a lower temperature, is difficult to send out during imidizate The molecular weight of raw polymer reduces, so preferably chemical imidization.

Chemical imidization can be by making the polyimide precursor for wanting to carry out imidizate in organic solvent in alkalinity Stirring is in the presence of catalyst to carry out.As organic solvent, the solvent used in aforementioned polymeric reaction can be used.As Basic catalyst can enumerate pyridine, triethylamine, trimethylamine, tri-n-butylamine, trioctylamine etc..Wherein, it is appropriate for instead due to having The alkalinity answered, therefore preferably triethylamine, pyridine.In addition, acetic anhydride, trimellitic anhydride, equal benzene four can be enumerated as acid anhydrides Acid anhydrides etc., wherein when using acetic anhydride, it is easy purification after the completion of reaction, so it is preferred that.

Temperature when carrying out imidization reaction is -20 DEG C~140 DEG C, preferably 0 DEG C~100 DEG C, can be in reaction Between to carry out under conditions of 1~100 hour.The amount of basic catalyst is 0.5~30 mole times of polyimide precursor, is preferably 2~20 moles times.The acid imide rates of resulting polymers can control by adjusting catalytic amount, temperature, reaction time.Acyl is sub- Remain the catalyst etc. added in solution after aminating reaction, it is therefore preferred to, recycled as following means obtained by Imide amination polymer, and be redissolved with organic solvent, so that aligning agent for liquid crystal of the invention be made.

It is above-mentioned it is such operate obtained from imide amination polymer solution by being injected into not while being sufficiently stirred Good solvent can be such that polymer is precipitated.It is precipitated and is cleaned with poor solvent for several times, then carried out air drying or heating is dry It is dry, the powder of the imide amination polymer through refining can be obtained.

Aforementioned poor solvent is not particularly limited, and can enumerate methanol, acetone, hexane, butyl cellosolve, heptane, first and second Ketone, methyl iso-butyl ketone (MIBK), ethyl alcohol, toluene, benzene etc..

Aligning agent for liquid crystal used in the present invention, which has, keeps aforementioned polyimide precursor or its imide amination polymer (following It is denoted as the polymer of specific structure) solution morphology of dissolution in organic solvent.The molecular weight of the polymer of specific structure is with weight Average molecular weight meter is preferably 2,000~500,000, more preferably 5,000~300,000, further preferably 8,000~100, 000.In addition, number-average molecular weight is preferably 1,000~250,000, more preferably 2,500~150,000, further preferably 4, 000~50,000.

The polymer concentration of aligning agent for liquid crystal used in the present invention can be fitted according to the setting of coating thickness to be formed Work as change, from uniform and flawless film this point is formed, preferably 1 weight % or more stablizes from the preservation of solution From the perspective of property, it is preferably set to 10 weight % or less.

As long as the polymer of the organic solvent uniform dissolution specific structure contained by aligning agent for liquid crystal used in the present invention, Just it is not particularly limited.If enumerating its concrete example, n,N-Dimethylformamide, N can be enumerated, N- diethylformamide, DMAC N,N' dimethyl acetamide, n-methyl-2-pyrrolidone, N- ethyl-2-pyrrolidone, N- methyl caprolactam, 2- pyrrolidines Ketone, n-vinyl-2-pyrrolidone, dimethyl sulfoxide, dimethyl sulfone, gamma-butyrolacton, 1,3- dimethyl-imidazolinone, 3- first Oxygroup-N, N- dimethylpropionamide etc..They can be used a kind or are mixed with two or more.Furthermore it is possible to be individually to deposit When can not uniform dissolution polymer solvent, as long as can also be mixed in above-mentioned in the range of polymer will not be precipitated Organic solvent.

Aligning agent for liquid crystal used in the present invention in addition to containing for dissolve specific structure polymer organic solvent it Outside, the solvent for being used to improve painting film uniformity when aligning agent for liquid crystal to be coated on to substrate can also be contained.The solvent is usual The surface tension solvent lower than above-mentioned organic solvent can be used.If enumerating its concrete example, can enumerate ethyl cellosolve, Butyl cellosolve, ethyl carbitol, butyl carbitol, ethylcarbitol acetate, ethylene glycol, 1- methoxy-2-propanol, 1- second Oxygroup -2- propyl alcohol, 1- butoxy -2- propyl alcohol, 1- phenoxy group -2- propyl alcohol, Propylene glycol monoacetate, propylene-glycol diacetate, third Glycol -1- monomethyl ether -2- acetic acid esters, propylene glycol -1- list ether -2- acetic acid esters, butyl cellosolve acetate, dipropylene glycol, 2- (2- ethoxy-c oxygroup) propyl alcohol, methyl lactate, ethyl lactate, lactic acid n-propyl ester, n-butyl lactate, isoamyl lactate etc..This Two or more can be applied in combination in a little solvents.

In aligning agent for liquid crystal of the invention, in addition to that mentioned above, in the range for not damaging effect of the present invention, it can also add The electrical characteristics such as the polymer other than polymer of the present invention, the dielectric constant for changing liquid crystal orientation film or electric conductivity Liquid is made for improving in dielectric substance or conductive materials, the silane coupling agent of adaptation for improving liquid crystal orientation film and substrate The cross-linked compound of film hardness or consistency when brilliant alignment films and pass through when being burnt into film for efficiently promoting Heat the imidizate promotor of imidizate etc. of polyimide precursor.

Liquid crystal orientation film of the invention is film obtained from above-mentioned aligning agent for liquid crystal to be coated on to substrate and drying, firing. As the substrate that be coated with aligning agent for liquid crystal of the invention, it is not particularly limited, can makes as long as the high substrate of the transparency Gone out with the viewpoint of plastic bases such as glass substrate, silicon nitride board, acrylic substrate, polycarbonate substrate etc., the chemical industry skill that conforms to the principle of simplicity Hair is, it is preferable to use be formed with the substrate of electrode for driving liquid crystal etc..In addition, the liquid crystal of reflection-type indicates in element, if only For unilateral substrate, then the opaque substance such as silicon wafer also can be used, electrode at this time can also use aluminium etc. can reflected light Material.

As the coating method of aligning agent for liquid crystal of the invention, spin-coating method, print process, ink-jet method etc. can be enumerated.Coating Drying, firing process after aligning agent for liquid crystal of the invention can choose arbitrary temperature and time.Generally for abundant removal Contained organic solvent, with 50 DEG C~120 DEG C drying 1 minute~10 minutes, thereafter with 150 DEG C~300 DEG C be burnt into 5 minutes~ 120 minutes.Coating thickness after firing is not particularly limited, and liquid crystal indicates that the reliability of element reduces sometimes when excessively thin, therefore For 5~300nm, preferably 10~200nm.

As the method for carrying out orientation process to gained liquid crystal orientation film, brushing method, light orientation position logos etc. can be enumerated.

As the concrete example of light orientation position logos, following method can be enumerated: one is biased to the irradiation of aforementioned film coated surface Determine the radiation in direction, according to circumstances further heated with 150~250 DEG C of temperature, assigns liquid crystal aligning ability Method.As radiation, ultraviolet light and luminous ray with 100nm~800nm wavelength can be used.

[liquid crystal expression element]

Element is indicated about liquid crystal of the invention, and band liquid crystal is obtained by aligning agent for liquid crystal of the invention by the above method and is taken To the substrate of film, after carrying out orientation process by brushing processing etc., liquid crystal, which is made, by known method indicates element.

Liquid crystal indicates that the manufacturing method of the liquid crystal cells of element is not particularly limited, if enumerating an example, common side Method is: by 1 pair of substrate for being formed with liquid crystal orientation film clamped in such a way that liquid crystal orientation film is facing towards inside preferably 1~30 μm, It after being arranged to more preferable 2~10 μm of spacer, is around fixed, inject liquid crystal and sealed with sealant.About enclosed liquid crystal Method is not particularly limited, and can exemplify: making after being depressurized in the liquid crystal cells of production, injects the vacuum method of liquid crystal；It is added dropwise The dripping method etc. being sealed after liquid crystal.Above-mentioned such operate and the liquid crystal orientation film obtained by aligning agent for liquid crystal of the invention has There is excellent characteristic, therefore, can be used as the liquid crystal such as VA, TN, STN, TFT, lateral electric-field type indicates element and ferroelectricity and anti- Ferroelectric liquid crystal indicates element liquid crystal orientation film.

Embodiment

It is exemplified below out embodiment, the present invention is described in more detail, but the present invention is not limited to these embodiments.

The abbreviation of compound used in the present embodiment and comparative example and the method for evaluating characteristics are as follows.

NMP:N- N-methyl-2-2-pyrrolidone N

BCS: butyl cellosolve

CA-1: benzenetetracarboxylic dianhydride

CA-2:3,3 ', 4,4 '-biphenyl tetracarboxylic dianhydrides

CA-3:1,2,3,4- cyclobutane tetracarboxylic dianhydride

Bis- (methoxycarbonyl) cyclobutane -1,3- dicarboxylic acids of CA-4:2,4-

CA-5:1,2,3,4- butane tetracarboxylic acid dianhydride

CA-6:1,2,4,5- pentane tetracarboxylic dianhydride

CA-7: bicyclic [3.3.0] octane -2,4,6,8- tetracarboxylic dianhydride

DA-1: bis- (4- amino-benzene oxygen) methane

Bis- (4- amino-benzene oxygen) propane of DA-2:1,3-

Bis- (4- amino-benzene oxygen) pentanes of DA-3:1,5-

The molecular weight of polyimide precursor and imide amination polymer in synthesis example uses room temperature gel permeation chromatography (GPC) device (GPC-101) (Showa Denko K. K's system), column (KD-803, KD-805) (Shodex corporation) are grasped as follows Make to measure.

Column temperature: 50 DEG C

Eluent: N, N '-dimethyl formamide is (as additive, lithium bromide monohydrate (LiBrH₂O) it is 30mmol/L (liter), phosphoric acid anhydrous crystalline (orthophosphoric acid) are 30mmol/L, tetrahydrofuran (THF) is 10ml/L)

Flow velocity: 1.0ml/ minutes

Standard curve making standard sample: TSK standard polyethylene oxide (molecular weight；About 900,000,150,000, 100,000 and 30,000) (TOSOH Co., Ltd's system) and polyethylene glycol (molecular weight；About 12,000,4,000 and 1,000) (Polymer Laboratories Ltd. system).

(measurement of the acid imide rate of imide amination polymer)

The acid imide rate of imide amination polymer in synthesis example is operated as follows to measure.Imidizate is polymerize Object powder 20mg is put into NMR (nuclear magnetic resonance) sample cell (NMR sample cell specification, φ 5 (wasteland's science Co. Ltd. system)), is added Add deuterated dimethyl sulfoxide (DMSO-d6,0.05 mass %TMS (tetramethylsilane) melange) (0.53ml), is made with ultrasonic wave It is completely dissolved.The solution is measured using NMR measuring machine (JNW-ECA500) (Japan Electronics データ system corporation) The proton NMR of 500MHz.Acid imide rate will be originated from the proton of the not changed structure in imidizate front and back as benchmark matter Son determines, uses the peak integrating value of the proton and the matter of the NH base from 9.5ppm~10.0ppm amic acid nearby occurred Sub- peak integrating value, is found out using the following formula.

Acid imide rate (%)=(1- α x/y) × 100

In above-mentioned formula, x is the proton peak integrating value of the NH base from amic acid, the peak integrating value that y is benchmark proton, α are NH matrix son 1 number ratio of the reference proton relative to amic acid when polyamic acid (acid imide rate is 0%).

[synthesis example 1]

DA-1 (6.9g, 30mmol) is put into subsidiary agitating device and the 100ml four-neck flask of subsidiary nitrogen ingress pipe, NMP 82.3g is added, stirs and makes it dissolve while supplying nitrogen.The diamine solution is stirred on one side, adds CA-1 on one side (5.9g, 27mmol), and then NMP 9.1g is added, it is stirred 12 hours using oil bath with 50 DEG C in a nitrogen atmosphere, to obtain Resin solid content concentration is the polyamic acid solution of 12 mass %.It is true using E type viscosimeter (Toki Sangyo Co., Ltd.'s system) The viscosity recognized at 25 DEG C of the polyamic acid solution is 68mPas.The molecular weight of the polyamic acid is Mn=8,500, Mw= 22,900。

[synthesis example 2]

To put into the 2000ml four-neck flask of subsidiary agitating device and subsidiary nitrogen ingress pipe DA-1 (136.5g, 593mmol), NMP 1532.8g is added, stirs and makes it dissolve while supplying nitrogen.Stir the diamine solution on one side, one CA-2 (166.1g, 564.5mmol) is added on side, and then adds NMP 170.3g, is stirred in a nitrogen atmosphere using oil bath with 50 DEG C It mixes 12 hours, to obtain the polyamic acid solution that resin solid content concentration is 15 mass %.The 25 of the polyamic acid solution Viscosity at DEG C is 504mPas.The molecular weight of the polyamic acid is Mn=12,000, Mw=30,300.

[synthesis example 3]

To put into the 300ml four-neck flask of subsidiary agitating device and subsidiary nitrogen ingress pipe DA-1 (20.5g, 89.0mmol), NMP 214.43g is added, stirs and makes it dissolve while supplying nitrogen.The diamine solution is stirred on one side, CA-3 (16.2g, 82.8mmol) is added on one side, and then adds NMP 53.6g, is stirred 12 hours with 23 DEG C in a nitrogen atmosphere, To obtain the polyamic acid solution that resin solid content concentration is 12 mass %.Viscosity at 25 DEG C of the polyamic acid solution For 72mPas.

[synthesis example 4]

In the 200ml four-neck flask of subsidiary agitating device and subsidiary nitrogen ingress pipe, by CA-4 (7.5g, 29.1mmol) Mixed in NMP 135.8g, add triethylamine (6.4g, 63mmol) and DA-1 (6.9g, 30mmol) thereto, and stir and It makes it dissolve.

The solution is stirred on one side, adds diphenyl (2,3- dihydro -2- thia -3- benzoxazoles) phosphonate ester on one side (24.2g, 63mmol), and then NMP 18.7g is added, it is stirred at room temperature 15 hours, to obtain the solution of poly amic acid ester. Viscosity at 25 DEG C of temperature of the polyamic acid ester solution is 110mPas.

The polyamic acid ester solution is put into isopropanol (1,196.7g), leaching gained sediment.By the sediment It after being cleaned with isopropanol, is dried under reduced pressure with 100 DEG C of temperature, obtains the powder of poly amic acid ester.The poly amic acid ester Molecular weight is Mn=9,900, Mw=21,800.

[synthesis example 5]

To put into the 2000ml four-neck flask of subsidiary agitating device and subsidiary nitrogen ingress pipe DA-1 (97.92g, 425.3mmol), NMP 924.8g is added, stirs and makes it dissolve while supplying nitrogen.The diamine solution is stirred on one side, CA-5 (83.41g, 420.7mmol) is added on one side, and then adds NMP 102.8g, in a nitrogen atmosphere using oil bath with 50 DEG C Stirring 12 hours, to obtain the polyamic acid solution that resin solid content concentration is 15 mass %.The polyamic acid solution Viscosity at 25 DEG C is 172mPas.In addition, the molecular weight of the polyamic acid be Mn=9,800, Mw=19,600.

[synthesis example 6]

After being diluted to 6 mass % to addition NMP in the polyamic acid solution (562.0g) obtained using synthesis example 5, make Acetic anhydride (197.5g) and pyridine (76.6g) are added for imidization catalyst, react it 5 hours with 50 DEG C.This is anti- Solution is answered to put into methanol (5772ml), leaching gained sediment.The sediment is cleaned with methanol, is subtracted with 100 DEG C It press dry dry and obtains imide amination polymer powder.The acid imide rate of the imide amination polymer is 84%, number-average molecular weight For 9,800, weight average molecular weight 19,300.

[synthesis example 7]

DA-1 (8.1g, 35mmol) is put into subsidiary agitating device and the 100ml four-neck flask of subsidiary nitrogen ingress pipe, NMP 76.7g is added, stirs and makes it dissolve while supplying nitrogen.The diamine solution is stirred on one side, adds CA-6 on one side (7.0g, 32.9mmol), and then NMP 8.52g is added, it is stirred 12 hours using oil bath with 40 DEG C in a nitrogen atmosphere, thus The polyamic acid solution for being 15 mass % to resin solid content concentration.Viscosity at 25 DEG C of the polyamic acid solution is 192mPa·s.The molecular weight of the polyamic acid is Mn=8,300, Mw=23,700.

[synthesis example 8]

To put into the 100ml four-neck flask of subsidiary agitating device and subsidiary nitrogen ingress pipe DA-1 (5.9g, 26.0mmol), NMP 79.9g is added, stirs and makes it dissolve while supplying nitrogen.Stir the diamine solution on one side, one CA-7 (6.1g, 24.4mmol) is added on side, and then adds NMP 8.9g, small with 50 DEG C of stirrings 12 using oil bath in a nitrogen atmosphere When, to obtain the polyamic acid solution that resin solid content concentration is 12 mass %.At 25 DEG C of the polyamic acid solution Viscosity is 72mPas.

[synthesis example 9]

To put into the 1000ml four-neck flask of subsidiary agitating device and subsidiary nitrogen ingress pipe DA-2 (51.7g, 200mmol), NMP 672.2g is added, stirs and makes it dissolve while supplying nitrogen.Stir the diamine solution on one side, one CA-1 (41.7g, 191.2mmol) is added on side, and then adds NMP 168.1g, is stirred in a nitrogen atmosphere using oil bath with 50 DEG C 24 hours, to obtain the polyamic acid solution that resin solid content concentration is 12 mass %.25 DEG C of the polyamic acid solution Under viscosity be 135mPas.In addition, the molecular weight of the polyamic acid be Mn=12,600, Mw=30,900.

[synthesis example 10]

DA-3 (6.9g, 24mmol) is put into subsidiary agitating device and the 100ml four-neck flask of subsidiary nitrogen ingress pipe, NMP 80.0g is added, stirs and makes it dissolve while supplying nitrogen.The diamine solution is stirred on one side, adds CA-1 on one side (5.0g, 23mmol) adds NMP in such a way that solid component concentration reaches 12 mass %, using oil bath with 50 DEG C of one evenings of stirring And obtain the solution of polyamic acid.Viscosity at 25 DEG C of the polyamic acid solution is 525mPas.In addition, the polyamic acid Molecular weight be Mn=14,800, Mw=32,500.

[embodiment 1]

NMP 19.0g, 3- amino are added into the polyamic acid solution 50.0g that the synthetic method using synthesis example 1 obtains Propyl-triethoxysilicane is nmp solution 6.0g and the BCS 25.0g of 1.0 weight %, obtains the liquid crystal that concentration is 6 mass % and takes To agent (A-1).It does not observe that muddy, precipitate generation etc. is abnormal in the aligning agent for liquid crystal (A-1), is confirmed as uniform molten Liquid.

[embodiment 2]

NMP 29.0g, 3- aminopropan are added into the molten 40.0g of polyamic acid that the synthetic method using synthesis example 2 obtains Ethyl triethoxy silicane alkane is nmp solution 6.0g and the BCS 25.0g of 1.0 weight %, obtains the liquid crystal aligning that concentration is 6 mass % Agent (A-2).It does not observe that muddy, precipitate generation etc. is abnormal in the aligning agent for liquid crystal (A-2), is confirmed as uniform solution.

[embodiment 3]

NMP 19.0g, 3- amino are added into the polyamic acid solution 50.0g that the synthetic method using synthesis example 3 obtains Propyl-triethoxysilicane is nmp solution 6.0g and the BCS 25.0g of 1.0 weight %, obtains the liquid crystal that concentration is 6 mass % and takes To agent (A-3).It does not observe that muddy, precipitate generation etc. is abnormal in the aligning agent for liquid crystal (A-3), is confirmed as uniform molten Liquid.

[embodiment 4]

NMP (113.3g) is added in the poly amic acid ester powder (10.0g) that the synthetic method using synthesis example 4 obtains, With 23 DEG C are stirred 12 hours and are made it dissolve.It is 1.0 weight %'s that 3-aminopropyltriethoxysilane is added into the solution Nmp solution 10.0g, BCS (33.3g), with 23 DEG C are stirred 2 hours and obtain aligning agent for liquid crystal (A-4).The aligning agent for liquid crystal (A- 4) it does not observe that muddy, precipitate generation etc. is abnormal in, is confirmed as uniform solution.

[embodiment 5]

NMP 29.0g, 3- amino are added into the polyamic acid solution 40.0g that the synthetic method using synthesis example 5 obtains Propyl-triethoxysilicane is nmp solution 6.0g and the BCS 25.0g of 1.0 weight %, obtains the liquid crystal that concentration is 6 mass % and takes To agent (A-5).It does not observe that muddy, precipitate generation etc. is abnormal in the aligning agent for liquid crystal (A-5), is confirmed as uniform molten Liquid.

[embodiment 6]

To addition NMP in the imide amination polymer powder (10.0g) that the synthetic method using synthesis example 6 obtains (113.3g), with 23 DEG C are stirred 12 hours and are made it dissolve.It is 1.0 that 3-aminopropyltriethoxysilane is added into the solution Nmp solution 10.0g, BCS (33.3g) of weight %, with 23 DEG C are stirred 2 hours and obtain aligning agent for liquid crystal (A-6).The liquid crystal takes It does not observe that muddy, precipitate generation etc. is abnormal in agent (A-6), is confirmed as uniform solution.

[embodiment 7]

NMP 29.0g, 3- amino are added into the polyamic acid solution 40.0g that the synthetic method using synthesis example 7 obtains Propyl-triethoxysilicane is nmp solution 6.0g and the BCS 25.0g of 1.0 weight %, obtains the liquid crystal that concentration is 6 mass % and takes To agent (A-7).It does not observe that muddy, precipitate generation etc. is abnormal in the aligning agent for liquid crystal (A-7), is confirmed as uniform molten Liquid.

[embodiment 8]

NMP 19.0g, 3- amino are added into the polyamic acid solution 50.0g that the synthetic method using synthesis example 8 obtains Propyl-triethoxysilicane is nmp solution 6.0g and the BCS 25.0g of 1.0 weight %, obtains the liquid crystal that concentration is 6 mass % and takes To agent (A-8).It does not observe that muddy, precipitate generation etc. is abnormal in the aligning agent for liquid crystal (A-8), is confirmed as uniform molten Liquid.

[comparative example 1]

NMP 19.0g, 3- amino are added into the polyamic acid solution 50.0g that the synthetic method using synthesis example 9 obtains Propyl-triethoxysilicane is nmp solution 6.0g and the BCS 25.0g of 1.0 weight %, obtains the liquid crystal that concentration is 6 mass % and takes To agent (B-1).It does not observe that muddy, precipitate generation etc. is abnormal in the aligning agent for liquid crystal (B-1), is confirmed as uniform molten Liquid.

[comparative example 2]

NMP 19.0g, 3- amino are added into the polyamic acid solution 50.0g that the synthetic method using synthesis example 10 obtains Propyl-triethoxysilicane is nmp solution 6.0g and the BCS 25.0g of 1.0 weight %, obtains the liquid crystal that concentration is 6 mass % and takes To agent (B-2).It does not observe that muddy, precipitate generation etc. is abnormal in the aligning agent for liquid crystal (B-2), is confirmed as uniform molten Liquid.

After gained aligning agent for liquid crystal is filtered with 1.0 μm of filter, it is spin-coated on the glass base of subsidiary transparent electrode On plate, after 2 minutes dry on 80 DEG C of hot plate, with 230 DEG C are burnt into 20 minutes and obtain the film of film thickness 100nm.Prepare this 2 substrates obtained from sample operation are added dropwise close after spreading 4 μm of pearl spacer in the liquid crystal alignment film surface of a substrate Seal agent (assisting vertical Chemical Co., Ltd. XN-1500T).Then, with the liquid crystal orientation film of another substrate facing towards inside, substrate Overlapping widths reach the mode of 1cm and be bonded.At this point, the tune in such a way that the diameter of the sealant after being bonded reaches about 3mm The dripping quantity of whole sealant.After 2 substrates of fitting are fixed with fixture, make its heat cure 1 hour with 120 DEG C, to make The sample of cementability evaluation.

The desktop precision universal testing machine AGS-X 500N that the sample of production is manufactured with Shimadzu Seisakusho Ltd. is fixed up and down It behind the end of substrate, is pressed from the top in substrate center portion, the pressure (N) when measurement is removed.Also, use is with by measuring Sealant diameter estimation area (mm²) pressure (N) is standardized obtained from value, implement the evaluation of bonding force.

The result for the bonding force implemented for aligning agent for liquid crystal A-1~A-8, B-1~B-2 is shown in table 1.

[table 1]

After gained aligning agent for liquid crystal is filtered with 1.0 μm of filter, it is spin-coated on the glass base of subsidiary transparent electrode On plate, after 2 minutes dry on 80 DEG C of hot plate, it is burnt into 20 minutes with 230 DEG C, to obtain the film of film thickness 100nm.It should Imide amination polymer film carries out brushing with rayon cloth and (roller diameter 120mm, revolving speed 1000rpm, movement speed 20mm/ seconds, presses Signature amount 0.4mm) after, 1 minute ultrasonic irradiation is carried out in pure water, it is 10 minutes dry with 80 DEG C.Prepare 2 this band liquid crystal The substrate of alignment films, after 4 μm of spacer is arranged in the liquid crystal alignment film surface of substrate, with the brushing direction of 2 substrates at It is combined for antiparallel mode, around sealing but leaves liquid crystal injecting port, the dummy cell that production unit spacing is 4 μm.? Under room temperature into the unit vacuum injection liquid crystal (MLC-2041, MERCK CORPORATION system), seal inlet and make anti- Parallel liquid crystal cells.

With the state of orientation of the polarized light microscope observing liquid crystal cells, it is denoted as " good " when not being orientated defect, exists " bad " is denoted as when being orientated defect.

After the liquid crystal cells are heated 30 minutes with 110 DEG C, the measurement of pre-tilt angle is carried out.Measurement has used オプトメトリ The Axo Scan Mueller Matrix Polarimeter of Network ス company manufacture.

The result of the pre-tilt angle implemented for aligning agent for liquid crystal A-1~A-8, B-1~B-2 and orientation is shown in table 2.

[table 2]

Industrial availability

Aligning agent for liquid crystal of the invention indicates to pass through raising in element in the narrow edge liquid crystal that can ensure larger expression face The cementability of sealant and liquid crystal orientation film and the expression for being able to solve adjacent edges is uneven, be industrially useful.

Claims

1. a kind of aligning agent for liquid crystal, which is characterized in that it is containing obtaining selected from reacting diamine component with tetracarboxylic acid derivatives To polyimide precursor and the polyimide precursor carried out obtained from imidizate in imide amination polymer at least 1 The aligning agent for liquid crystal of kind, the polyimide precursor have repetitive unit shown in following formula (1),

In formula (1), Y is the divalent organic group from diamine component, and X is the 4 valence organic groups from tetracarboxylic acid derivatives, A¹With A²It is each independently the alkyl of hydrogen atom or the optionally carbon number 1~10 with substituent group, optionally with the carbon number of substituent group The alkynyl of 1~10 alkenyl, the optionally carbon number 1~10 with substituent group, R¹For hydrogen atom or the alkyl of carbon number 1~10, at least A part of Y is the structure of following formula (2),

In repetitive unit shown in the formula (1), at least part X is that 4 valences with ester ring type structure or aliphatic structure have Machine group.

2. aligning agent for liquid crystal according to claim 1, wherein in repetitive unit shown in the formula (1), at least part X is the structure in following (X-9), (X-26), (X-27),

3. aligning agent for liquid crystal according to claim 1, wherein in repetitive unit shown in the formula (1), X is with rouge The ratio of 4 valence organic groups of ring structures or aliphatic structure is 10~100 moles of %.

4. aligning agent for liquid crystal according to claim 2, wherein in repetitive unit shown in the formula (1), X be (X-9), (X-26), the ratio of the arbitrary structures in (X-27) is 10~100 moles of %.

5. aligning agent for liquid crystal according to any one of claims 1 to 4, wherein repetitive unit shown in the formula (1) In, Y is that the ratio of the structure of formula (2) is 10~100 moles of %.

6. a kind of liquid crystal orientation film is that aligning agent for liquid crystal according to any one of claims 1 to 5 is coated on substrate and is burnt Obtained from.

7. a kind of liquid crystal indicates element, with liquid crystal orientation film as claimed in claim 6.