WO2014133042A1

WO2014133042A1 - Polymer, liquid crystal alignment treatment agent, liquid crystal alignment film, and liquid crystal display element

Info

Publication number: WO2014133042A1
Application number: PCT/JP2014/054766
Authority: WO
Inventors: 奈穂菊池; 徳俊三木; 幸司巴; 雅章片山; 保坂　和義
Original assignee: 日産化学工業株式会社
Priority date: 2013-02-28
Filing date: 2014-02-26
Publication date: 2014-09-04
Also published as: JP6368955B2; KR102184058B1; TWI620791B; JP6504377B2; CN105164579A; TW201500462A; KR20150122210A; JPWO2014133042A1; JP2018087343A; CN105164579B

Abstract

Provided is a liquid crystal alignment treatment agent that contains at least one polymer chosen from among polyimide precursors obtained by reacting a diamine component including a diamine compound having a side chain as shown in formula [2] with a tetracarboxylic acid component including a tetracarboxylic dianhydride as shown in formula [1] and polyimides obtained by imidization of the polyimide precursor. (In formula [2], Y¹ indicates a single bond, −(CH₂)_a− (wherein a is an integer from 1 to 15), −O−, or the like; Y² indicates a single bond or −(CH₂)_b− (wherein b is an integer from 1 to 15); Y³ indicates a single bond, −(CH₂)_c− (wherein c is an integer from 1 to 15), −O−, or the like; Y⁴ indicates a benzene ring, a cyclohexane ring, or the like; Y⁵ indicates a benzene ring, a cyclohexane ring, or the like; n is an integer from 0 to 4; and Y⁶ indicates a C1−18 alkyl group or the like.)

Description

Polymer, liquid crystal alignment treatment agent, liquid crystal alignment film, and liquid crystal display element

The present invention relates to a polymer, a liquid crystal alignment treatment agent used in the production of a liquid crystal display element, a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent, and a liquid crystal display element using the liquid crystal alignment film.

An MVA (Multi-domain Vertical Alignment) mode capable of obtaining a wide viewing angle is known as a liquid crystal display device that is superior in viewing angle characteristics as compared with a conventional TN (Twisted Nematic) mode liquid crystal display device. In the MVA mode, a liquid crystal having negative dielectric anisotropy, a liquid crystal alignment film for vertically aligning the liquid crystal, and an alignment control structure for controlling the alignment direction of the liquid crystal are used. When a voltage is applied, the liquid crystal is tilted in a vertical direction along the alignment control structure. However, in the MVA mode, since the protrusion of the alignment control structure is formed in the pixel, the aperture ratio is lower than that of the TN mode or the like, and the light transmittance from the backlight is lowered.

In order to solve this problem, in order to further increase the response speed of the liquid crystal with high light transmittance, a method of controlling the alignment direction of the liquid crystal during driving using a polymer has been proposed (for example, Patent Document 1). reference). In this method, a liquid crystal material in which a liquid crystal is mixed with a polymerizable compound (also referred to as a monomer) that is polymerized by heat or ultraviolet irradiation is used. In this method, a voltage is applied between the substrates to tilt the liquid crystal molecules, and then the monomer is polymerized by heat or ultraviolet irradiation to form a polymer (the above method is also referred to as PSA treatment). Accordingly, a liquid crystal layer having a predetermined tilt angle (also referred to as a pretilt angle) can be obtained even when no voltage is applied, and a liquid crystal display element having a high light transmittance and a faster liquid crystal response speed can be obtained.

JP 2003-149647 A

For the production of a liquid crystal display element, a step of filling a liquid crystal between two substrates (cell gaps) on which a liquid crystal alignment film is formed is necessary. Until now, the filling of liquid crystal has been generally performed by a vacuum injection method in which a liquid crystal is filled between two substrates by utilizing a pressure difference between atmospheric pressure and vacuum. However, at present, a liquid crystal dropping method (ODF (One Drop Fill) method) is used as a liquid crystal filling method for the purpose of improving production efficiency.

In the ODF method, the liquid crystal is directly dropped on the liquid crystal alignment film, so that the liquid crystal alignment film is physically stressed when the liquid crystal is dropped, and it is necessary to fill the liquid crystal over the entire panel, and it is necessary to increase the dropping point of the liquid crystal. is there. Therefore, so-called alignment unevenness such as dripping traces and lattice unevenness occurs in the liquid crystal dropping portion or the portion where the liquid crystal droplets are in contact with the adjacent liquid droplets. When this is used as a liquid crystal display element, display unevenness due to alignment unevenness occurs. There was a problem that occurred.

Further, when the liquid crystal display element is heated by irradiation of the backlight that constitutes the liquid crystal display element, there is a problem that the pretilt angle changes and display defect occurs. For this reason, high stability to heat is required.

Accordingly, an object of the present invention is to provide a polymer, a liquid crystal alignment treatment agent, a liquid crystal alignment film, and a liquid crystal display element that can improve the alignment unevenness of the liquid crystal alignment film and are excellent in heat resistance of the pretilt angle.

As a result of earnest research, the inventor has obtained a polyimide precursor obtained by reacting a tetracarboxylic acid component having a tetracarboxylic dianhydride having a specific structure with a diamine component having a diamine compound having a specific structure, and The liquid crystal aligning agent containing at least one polymer selected from polyimides obtained by imidizing the polyimide precursor is found to be extremely effective for achieving the above object, and the present invention is completed. It came to.

That is, the present invention has the following gist.
(1) Obtained by reacting a tetracarboxylic acid component containing a tetracarboxylic dianhydride represented by the following formula [1] with a diamine component containing a diamine compound having a side chain represented by the following formula [2] The liquid crystal aligning agent characterized by including the polyimide precursor and the at least 1 polymer chosen from the polyimide obtained by imidating this polyimide precursor.

(In formula [2], Y ¹ represents a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or —OCO—. Y ² represents a single bond or — (CH ₂ ) _b — (b is an integer of 1 to 15), Y ³ is a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15) ), —O—, —CH ₂ O—, —COO— or —OCO—, wherein Y ⁴ is a carbon having a divalent cyclic group selected from a benzene ring, a cyclohexane ring or a heterocyclic ring, or a steroid skeleton A divalent organic group having 17 to 51, wherein any hydrogen atom on the cyclic group contains an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, or fluorine having 1 to 3 carbon atoms May be substituted with an alkyl group, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom , Y ⁵ represents a divalent cyclic group selected from benzene ring, cyclohexane ring or a heterocyclic ring, any hydrogen atom on these cyclic groups, an alkyl group having 1 to 3 carbon atoms, having 1 to 3 carbon atoms May be substituted with an alkoxyl group, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom, n represents an integer of 0 to 4, and Y ⁶ represents a carbon number An alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 18 carbon atoms).

(2) The liquid crystal aligning agent according to the above (1), wherein the tetracarboxylic acid component contains a tetracarboxylic acid anhydride represented by the following formula [3].

(In Formula [3], Z ¹ is at least one tetravalent group selected from Formula [3a] to Formula [3j] below).

(In the formula [3a], Z ² to Z ⁵ represent a hydrogen atom, a methyl group, a chlorine atom or a benzene ring, and may be the same or different. In the formula [3g], Z ⁶ and Z ⁷ are A hydrogen atom or a methyl group, which may be the same or different.

(3) The solvent according to (1) or (2) above, which contains N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone as a solvent in the liquid crystal aligning agent Liquid crystal alignment treatment agent.

(4) Any one of (1) to (3) above, which contains a solvent selected from the solvents represented by the following formulas [D-1] to [D-3] as a solvent in the liquid crystal aligning agent Liquid crystal aligning agent as described in.

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

(5) A liquid crystal alignment film obtained by using the liquid crystal aligning agent described in (1) to (4) above.

(6) A liquid crystal alignment film obtained by an ink jet method using the liquid crystal aligning agent described in (1) to (4) above.

(7) A liquid crystal display element comprising the liquid crystal alignment film according to (5) or (6).

(8) A liquid crystal composition having a liquid crystal layer between a pair of substrates provided with electrodes and including a polymerizable compound that is polymerized by at least one of active energy rays and heat is disposed between the pair of substrates. The liquid crystal alignment film according to (5) or (6), wherein the liquid crystal alignment film is used for a liquid crystal display device produced through a step of polymerizing the polymerizable compound while applying a voltage between the electrodes.

(9) A liquid crystal display element comprising the liquid crystal alignment film according to (8).

(10) A liquid crystal alignment film comprising a liquid crystal layer between a pair of substrates provided with electrodes and including a polymerizable group that is polymerized by at least one of active energy rays and heat is disposed between the pair of substrates. The liquid crystal alignment film according to (5) or (6), wherein the liquid crystal alignment film is used for a liquid crystal display device produced through a step of polymerizing the polymerizable group while applying a voltage between the electrodes.

(11) A liquid crystal display element comprising the liquid crystal alignment film according to (10).

(12) Obtained by reacting a tetracarboxylic acid component containing a tetracarboxylic dianhydride represented by the following formula [1] with a diamine component containing a diamine compound having a side chain represented by the following formula [2] A polymer comprising at least one selected from a polyimide precursor obtained and a polyimide obtained by imidizing the polyimide precursor.

According to the present invention, a polyimide precursor obtained by reacting a tetracarboxylic acid component containing a tetracarboxylic dianhydride having a specific structure with a diamine component containing a diamine compound having a side chain of a specific structure, and the polyimide precursor By using a liquid crystal aligning agent containing at least one polymer selected from polyimides obtained by imidizing the body, alignment unevenness generated in a liquid crystal display device produced by the ODF method can be improved. In particular, when the PSA mode is adopted, the dispersibility of the polymerizable compound contained in the liquid crystal display element can be made uniform, and the alignment unevenness can be further improved. Moreover, the heat resistance of a pretilt angle can be made excellent by using the liquid-crystal aligning agent of this invention. Therefore, the liquid crystal display element having the liquid crystal alignment film of the present invention does not have alignment defects due to alignment unevenness and has excellent heat resistance, so that it becomes a highly reliable liquid crystal display element.

The liquid-crystal aligning agent of this invention is a tetracarboxylic-acid component containing the tetracarboxylic dianhydride (it is also called specific tetracarboxylic dianhydride) shown by following formula [1], and following formula [2] At least one selected from a polyimide precursor obtained by reacting a diamine component containing a diamine compound having a side chain shown (also referred to as a specific side chain diamine compound) and a polyimide obtained by imidizing the polyimide precursor The polymer (also referred to as a specific polymer).

Here, the polyimide precursor refers to polyamic acid (also called polyamic acid) or polyamic acid alkyl ester. The polyimide precursor is composed of a tetracarboxylic acid component (eg, a tetracarboxylic acid compound, a tetracarboxylic dianhydride, a dicarboxylic acid dihalide compound, a dicarboxylic acid dialkyl ester compound, a dialkyl ester dihalide compound) and a primary or secondary molecule. It is obtained by reaction with a diamine component, which is a diamine compound having two amino groups, and polyimide is obtained by dehydrating and ring-closing (imidizing) this polyamic acid, or by heating and ring-closing (imidizing) a polyamic acid alkyl ester. It is done. Any of the polyamic acid, polyamic acid alkyl ester, and polyimide is useful as a specific polymer to be contained in the liquid crystal aligning agent of the present invention.

<Specific tetracarboxylic dianhydride>
The specific tetracarboxylic dianhydride contained in the tetracarboxylic acid component that is the raw material of the polymer contained in the liquid crystal aligning agent of the present invention is a tetracarboxylic dianhydride represented by the following formula [1].

The tetracarboxylic dianhydride represented by the formula [1] is preferably 20 mol% to 100 mol% in the total tetracarboxylic acid component. In particular, it is preferably 30 mol% to 70 mol%. Particularly preferred is 30 to 50 mol%.

<Other tetracarboxylic acid compounds>
In the present invention, as long as the effects of the present invention are not impaired, other tetracarboxylic acid compounds (also referred to as other tetracarboxylic acid compounds) other than the specific tetracarboxylic dianhydride may be used in combination as a tetracarboxylic acid component. it can.

Among these, tetracarboxylic dianhydrides represented by the following formula [3] and tetracarboxylic acid compounds and dicarboxylic acid dihalide compounds (which are collectively referred to as other tetracarboxylic acid compounds) are tetracarboxylic acid derivatives thereof. It is preferable to use it.

(In formula [3], Z ¹ is a group having a structure selected from the following formulas [3a] to [3j].)

In the formula [3a], Z ² to Z ⁵ represent a hydrogen atom, a methyl group, a chlorine atom or a benzene ring, and may be the same or different.

In the formula [3g], Z ⁶ and Z ⁷ represent a hydrogen atom or a methyl group, and may be the same or different.

In the structure represented by the formula [3], Z ¹ represents the formula [3a], the formula [3c], the formula [3d], the formula from the viewpoint of easy synthesis and the ease of the polymerization reaction when producing the polymer. A structure represented by [3e], formula [3f] or formula [3g] is preferable. More preferred is a structure represented by formula [3a], formula [3e], formula [3f] or formula [3g], and particularly preferred is formula [3e], formula [3f] or formula [3g]. It is.

As long as the tetracarboxylic acid component in the specific polymer contained in the liquid crystal aligning agent of the present invention does not impair the effects of the present invention, the tetracarboxylic acid compound other than the specific tetracarboxylic dianhydride and other tetracarboxylic acid compounds It can also be used.

Specific examples thereof include the following tetracarboxylic dianhydrides, tetracarboxylic acid compounds or dicarboxylic acid dihalide compounds.

That is, pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6 , 7-anthracenetetracarboxylic acid, 1,2,5,6-anthracenetetracarboxylic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′, 4′-biphenyltetracarboxylic acid Bis (3,4-dicarboxyphenyl) ether, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid, bis (3,4-dicarboxyphenyl) sulfone, bis (3,4-dicarboxyphenyl) Methane, 2,2-bis (3,4-dicarboxyphenyl) propane, 1,1,1,3,3,3-hexafluoro-2,2-bis (3,4-dicarboxyphenyl) Nyl) propane, bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4-dicarboxyphenyl) diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis (3 , 4-dicarboxyphenyl) pyridine, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid or 1,3-diphenyl-1,2,3 4-cyclobutanetetracarboxylic acid.

Other tetracarboxylic acid compounds and the above-mentioned tetracarboxylic acid compounds are the solubility of the specific polymer of the present invention in a solvent, the coating property of a liquid crystal aligning agent, the alignment property of liquid crystal when used as a liquid crystal alignment film, and the voltage holding ratio. Depending on the characteristics such as accumulated charge, one kind or a mixture of two or more kinds may be used.

<Specific side chain diamine compound>
The specific side chain diamine compound contained in the diamine component that is the raw material of the polymer contained in the liquid crystal aligning agent of the present invention is a diamine compound having a side chain represented by the following formula [2]. In the present specification, the side chain of the diamine compound means a structure branched from a structure connecting two amino groups.

The diamine compound having a side chain represented by the formula [2] is preferably 20 mol% to 70 mol% in the total diamine component. In particular, the content is preferably 20 mol% to 50 mol%. Particularly preferred is 20 mol% to 40 mol%.

In the formula [2], Y ¹ represents a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or —OCO—. . Among these, from the viewpoint of availability of raw materials and ease of synthesis, a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O— or —COO -Is preferred. More preferred is a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 10), —O—, —CH ₂ O— or —COO—.

In the formula [2], Y ² represents a single bond or — (CH ₂ ) _b — (b is an integer of 1 to 15). Among these, a single bond or — (CH ₂ ) _b — (b is an integer of 1 to 10) is preferable.

In the formula [2], Y ³ represents a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or —OCO—. . Of these, a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15), —O—, —CH ₂ O— or —COO— is preferable from the viewpoint of ease of synthesis. More preferred is a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 10), —O—, —CH ₂ O— or —COO—.

In the formula [2], Y ⁴ is a divalent cyclic group selected from a benzene ring, a cyclohexane ring or a heterocyclic ring, and an arbitrary hydrogen atom on these cyclic groups is an alkyl group having 1 to 3 carbon atoms, carbon It may be substituted with an alkoxyl group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom. Furthermore, Y ⁴ may be a divalent organic group selected from organic groups having 17 to 51 carbon atoms and having a steroid skeleton. Among these, an organic group having 17 to 51 carbon atoms having a benzene ring, a cyclohexane ring or a steroid skeleton is preferable from the viewpoint of ease of synthesis.

In formula [2], Y ⁵ represents a divalent cyclic group selected from a benzene ring, a cyclohexane ring or a heterocyclic ring, and any hydrogen atom on these cyclic groups is an alkyl group having 1 to 3 carbon atoms, carbon It may be substituted with an alkoxyl group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom. Of these, a benzene ring or a cyclohexane ring is preferable.

In the formula [2], n represents an integer of 0 to 4. Among these, 0 to 3 are preferable from the viewpoint of availability of raw materials and ease of synthesis. More preferred is 0-2.

In the formula [2], Y ⁶ represents an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 18 carbon atoms. . Of these, an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 10 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 10 carbon atoms is preferable. More preferably, it is an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms. Particularly preferred is an alkyl group having 1 to 9 carbon atoms or an alkoxyl group having 1 to 9 carbon atoms.

Preferred combinations of Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ , Y ⁶ and n in the formula [2] are listed in Tables 6 to 47 on pages 13 to 34 of International Publication No. WO2011 / 132751. And the same combinations as (2-1) to (2-629). In each table of the International Publication, Y ¹ to Y ⁶ in the present invention are shown as Y ¹ to Y ⁶ , but Y ¹ to Y ⁶ are read as Y ¹ to Y ⁶ . Further, an organic group having 12 to 25 carbon atoms having a steroid skeleton is read as an organic group having 17 to 51 carbon atoms having a steroid skeleton.

Specific examples of the diamine compound having a side chain represented by the formula [2] include diamine compounds represented by the following formulas [2b-1] to [2b-31].

(In the formulas [2b-1] to [2b-3], R ¹ represents —O—, —OCH ₂ —, —CH ₂ O—, —COOCH ₂ — or CH ₂ OCO—, and R ² represents carbon An alkyl group, an alkoxy group, a fluorine-containing alkyl group or a fluorine-containing alkoxy group represented by formulas 1 to 22.

(In the formulas [2b-4] to [2b-6], R ³ represents —COO—, —OCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O—, —OCH ₂ — or — CH ₂ - indicates, ^{R 4} represents an alkyl group, alkoxy group, fluorine-containing alkyl group or fluorine-containing alkoxy group of 1 to 22 carbon atoms).

(In the formulas [2b-7] and [2b-8], R ⁵ represents —COO—, —OCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O—, —OCH ₂ —, — CH ₂ — or —O—, and R ⁶ is a fluorine group, a cyano group, a trifluoromethane group, a nitro group, an azo group, a formyl group, an acetyl group, an acetoxy group or a hydroxyl group).

(In Formula [2b-9] and Formula [2b-10], R ⁷ represents an alkyl group having 3 to 12 carbon atoms. Note that the cis-trans isomerism of 1,4-cyclohexylene is the trans isomer. preferable).

(In the formulas [2b-11] and [2b-12], R ⁸ represents an alkyl group having 3 to 12 carbon atoms. The cis-trans isomerism of 1,4-cyclohexylene is the trans isomer. preferable).

(In the formula [2b-13], B ⁴ represents an alkyl group having 3 to 20 carbon atoms which may be substituted with a fluorine atom, and B ³ represents a 1,4-cyclohexylene group or a 1,4-phenylene group. B ² represents an oxygen atom or —COO— * (where a bond marked with “*” binds to B ³ ), and B ¹ represents an oxygen atom or —COO— * (where “*” bond marked with represents a _(CH 2) bind to ^{a 2).} Further, ^{a 1} represents an integer of 0 or 1, ^{a 2} represents an integer of 2 ~ 10, ^{a 3} is 0 or 1 Indicates an integer).

The liquid crystal aligning agent using the diamine compound having a side chain represented by the formula [2] can increase the pretilt angle of the liquid crystal when the liquid crystal alignment film is used. At that time, for the purpose of enhancing these effects, among the above diamine compounds, the diamine compounds represented by the formulas [2b-1] to [2b-13] or the formulas [2b-22] to [2b-31] Is preferably used. More preferred are diamine compounds represented by the formulas [2b-1] to [2b-12] or the formulas [2b-22] to [2b-29]. Moreover, in order to improve these effects, it is preferable that these diamine compounds are 5 mol% or more and 80 mol% or less of the whole diamine component. More preferably, these diamine compounds are 5 mol% or more and 60 mol% or less of the whole diamine component from the point of the applicability | paintability of a liquid crystal aligning agent, and the electrical property as a liquid crystal aligning film.

The diamine compound having a side chain represented by the formula [2] is a solubility of a specific polymer in a solvent, a coating property of a liquid crystal aligning agent, a liquid crystal alignment property in a liquid crystal alignment film, a voltage holding ratio, One type or a mixture of two or more types can be used in accordance with characteristics such as accumulated charge.

<Other diamine components>
As a diamine component for producing the specific polymer contained in the liquid crystal aligning agent of the present invention, a known diamine compound can be used in addition to the diamine compound having a side chain represented by the formula [2].

Especially, it is preferable to use the diamine compound which has a structure shown by the following formula [4a].

In the formula [4a], a represents an integer of 0 to 4. Especially, the integer of 0 or 1 is preferable from the point of the availability of a raw material or the ease of a synthesis | combination.

Specific examples of the diamine compound having a structure represented by the formula [4a] include a diamine compound represented by the following formula [4a-1].

In the formula [4a-1], a represents an integer of 0 to 4. Among these, 0 or 1 is preferable from the viewpoint of availability of raw materials and ease of synthesis.

In the formula [4a-1], n represents an integer of 1 to 4. Among these, 1 is preferable from the viewpoint of ease of synthesis.

The method for producing the diamine compound represented by the formula [4a] is not particularly limited, but preferred methods include those shown below. As an example, a diamine compound represented by the formula [4a-1] is obtained by synthesizing a dinitro compound represented by the following formula [4a-A], and further reducing the nitro group to convert it to an amino group. It is done.

(In the formula [4a-A], a represents an integer of 0 to 4 and n represents an integer of 1 to 4).

The method for reducing the dinitro group of the dinitro compound represented by the formula [4a-A] is not particularly limited, and is usually palladium-carbon in a solvent such as ethyl acetate, toluene, tetrahydrofuran, dioxane or an alcohol solvent. There is a method in which platinum oxide, Raney nickel, platinum black, rhodium-alumina, platinum sulfide carbon, or the like is used as a catalyst and reacted in hydrogen gas, hydrazine, or hydrogen chloride.

Examples of the diamine compound represented by the formula [4a] further include diamine compounds represented by the following formulas [4a-2] to [4a-5].

In the formula [4a-2], A ¹ is a single bond, —CH ₂ —, —C ₂ H ₄ —, —C (CH ₃ ) ₂ —, —CF ₂ —, —C (CF ₃ ) ₂ —, — O—, —CO—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CH ₂ O—, —OCH ₂ —, —COO—, —OCO—, —CON (CH ₃ ) — or —N (CH ₃ ) CO—. Among these, from the viewpoint of ease of synthesis, a single bond, —CH ₂ —, —C (CH ₃ ) ₂ —, —O—, —CO—, —NH—, —N (CH ₃ ) —, —CONH —, —NHCO—, —COO— or —OCO— is preferred. More preferred is a single bond, —CH ₂ —, —C (CH ₃ ) ₂ —, —O—, —CO—, —NH— or —N (CH ₃ ) —.

In the formula [4a-2], m ¹ and m ² each represent an integer of 0 to 4, and m ¹ + m ² represents an integer of 1 to 4. Among ^them, m 1 + ^{m 2} is 1 or 2 are preferred.

In the formula [4a-3], m ³ and m ⁴ each represent an integer of 1 to 5. Of these, 1 or 2 is preferable from the viewpoint of ease of synthesis.

In the formula [4a-4], A ² represents a linear or branched alkyl group having 1 to 5 carbon atoms. Of these, a linear alkyl group having 1 to 3 carbon atoms is preferable.

In formula [4a-4], m ⁵ represents an integer of 1 to 5. Of these, 1 or 2 is preferable.

In the formula [4a-5], A ³ is a single bond, —CH ₂ —, —C ₂ H ₄ —, —C (CH ₃ ) ₂ —, —CF ₂ —, —C (CF ₃ ) ₂ —, — O—, —CO—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CH ₂ O—, —OCH ₂ —, —COO—, —OCO—, —CON (CH ₃ ) — or —N (CH ₃ ) CO—. Among them, a single bond, —CH ₂ —, —C (CH ₃ ) ₂ —, —O—, —CO—, —NH—, —CONH—, —NHCO—, —CH ₂ O—, —OCH ₂ — , —COO— or —OCO— is preferable. More preferred is —O—, —CO—, —NH—, —CONH—, —NHCO—, —CH ₂ O—, —OCH ₂ —, —COO— or —OCO—.

In the formula [4a-5], m ⁶ represents an integer of 1 to 4. Of these, 1 is preferable from the viewpoint of ease of synthesis.

The diamine compound represented by the formula [4a-1] to the formula [4a-5] is preferably 30 mol% to 80 mol%, more preferably 50 mol% to 80 mol%, based on the total diamine component. It is preferable that

The diamine compounds represented by the above formulas [4a-1] to [4a-5] are soluble in a specific polymer in a solvent, applicability of a liquid crystal aligning agent, and alignment of liquid crystals when used as a liquid crystal alignment film. Depending on the characteristics such as voltage holding ratio and accumulated charge, one kind or a mixture of two or more kinds can be used.

As the diamine component for producing the specific polymer contained in the liquid crystal aligning agent of the present invention, it is also preferable to use a diamine compound represented by the following formula [4b].

In the formula [4b], Y represents at least one monovalent group selected from the following formula [4b-1], formula [4b-2], formula [4b-3], or formula [4b-4]. , M represents an integer of 0 to 4, and — (Y) _m represents that there are m substituents Y.

In the formula [4b-1], a represents an integer of 0 to 4. Especially, the integer of 0 or 1 is preferable from the point of the availability of a raw material or the ease of a synthesis | combination.

In the formula [4b-2], Y ⁷ represents an alkyl group having 8 to 22 carbon atoms.

In the formula [4b-3], Y ⁸ and Y ⁹ each independently represent a hydrocarbon group having 1 to 12 carbon atoms.

In the formula [4b-4], Y ¹⁰ represents an alkyl group having 1 to 8 carbon atoms.

The method for producing the diamine compound represented by the formula [4b] is not particularly limited, but preferred methods include those shown below.

As an example, a diamine compound represented by the formula [4b] can be obtained by synthesizing a dinitro compound represented by the following formula [4b-A] and further reducing the nitro group to convert it to an amino group.

(In Formula [4b-A], Y represents a substituent having at least one structure selected from Formula [4b-1], Formula [4b-2], Formula [4b-3] or Formula [4b-4]. M represents an integer of 0 to 4).

The method for reducing the dinitro group of the dinitro compound represented by the formula [4b-A] is not particularly limited, and is usually palladium-carbon in a solvent such as ethyl acetate, toluene, tetrahydrofuran, dioxane or an alcohol solvent. There is a method in which platinum oxide, Raney nickel, platinum black, rhodium-alumina, platinum sulfide carbon, or the like is used as a catalyst and reacted in hydrogen gas, hydrazine, or hydrogen chloride.

Specific examples of the structure of the diamine compound represented by the formula [4b] are given below, but are not limited to these examples.

That is, the diamine compound represented by the formula [4b] includes m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 2,6-diaminotoluene, 2,4-diaminophenol, 3,5-diaminophenol. In addition to 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol and 4,6-diaminoresorcinol, diamine compounds having structures represented by the following formulas [4b-6] to [4b-15] are exemplified. be able to.

(In the formulas [4b-6] to [4b-9], A ¹ represents an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group).

Examples of the diamine component for producing the specific polymer contained in the liquid crystal aligning agent of the present invention include diamine compounds represented by the formulas [4a-1] to [4a-5] and diamines represented by the formula [4b]. Diamine compounds other than the compounds (also referred to as other diamine compounds) can be used as the diamine component. Although the specific example is given to the following, it is not limited to these examples.

For example, 4,4′-diaminobiphenyl, 3,3′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dimethoxy-4,4′-diaminobiphenyl, 3,3′-dihydroxy-4,4 '-Diaminobiphenyl, 3,3'-dicarboxy-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 3,3'-trifluoromethyl-4,4'- Diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane 3,4′-diaminodiphenylmethane, 2,2′-diaminodiphenylmethane, 2,3′-diaminodiphenylmethane, 4, '-Diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3'-diaminodiphenyl ether, 4,4'-sulfonyldianiline, 3,3' -Sulfonyldianiline, bis (4-aminophenyl) silane, bis (3-aminophenyl) silane, dimethyl-bis (4-aminophenyl) silane, dimethyl-bis (3-aminophenyl) silane, 4,4'- Thiodianiline, 3,3'-thiodianiline, 4,4'-diaminodiphenylamine, 3,3'-diaminodiphenylamine, 3,4'-diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, N -Methyl (4,4'-diame Diphenyl) amine, N-methyl (3,3′-diaminodiphenyl) amine, N-methyl (3,4′-diaminodiphenyl) amine, N-methyl (2,2′-diaminodiphenyl) amine, N-methyl ( 2,3′-diaminodiphenyl) amine, 4,4′-diaminobenzophenone, 3,3′-diaminobenzophenone, 3,4′-diaminobenzophenone, 1,4-diaminonaphthalene, 2,2′-diaminobenzophenone, 2, , 3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2, , 7-Diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis (4-amino Phenyl) ethane, 1,2-bis (3-aminophenyl) ethane, 1,3-bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, 1,4-bis (4 -Aminophenyl) butane, 1,4-bis (3-aminophenyl) butane, bis (3,5-diethyl-4-aminophenyl) methane, 1,4-bis (4-aminophenoxy) benzene, 1,3 -Bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis (4-aminobenzyl) benzene, , 3-bis (4-aminophenoxy) benzene, 4,4 ′-[1,4-phenylenebis (methylene)] dianiline, 4,4 ′-[1,3-phenylenebis (methylene)] dia Phosphorus, 3,4 '-[1,4-phenylenebis (methylene)] dianiline, 3,4'-[1,3-phenylenebis (methylene)] dianiline, 3,3 '-[1,4-phenylenebis (Methylene)] dianiline, 3,3 ′-[1,3-phenylenebis (methylene)] dianiline, 1,4-phenylenebis [(4-aminophenyl) methanone], 1,4-phenylenebis [(3- Aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone], 1,3-phenylenebis [(3-aminophenyl) methanone], 1,4-phenylenebis (4-aminobenzoate) 1,4-phenylenebis (3-aminobenzoate), 1,3-phenylenebis (4-aminobenzoate), 1,3-phenylenebis (3-aminobenzoate) Zoate), bis (4-aminophenyl) terephthalate, bis (3-aminophenyl) terephthalate, bis (4-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, N, N ′-(1,4 -Phenylene) bis (4-aminobenzamide), N, N '-(1,3-phenylene) bis (4-aminobenzamide), N, N'-(1,4-phenylene) bis (3-aminobenzamide) N, N ′-(1,3-phenylene) bis (3-aminobenzamide), N, N′-bis (4-aminophenyl) terephthalamide, N, N′-bis (3-aminophenyl) terephthalamide N, N′-bis (4-aminophenyl) isophthalamide, N, N′-bis (3-aminophenyl) isophthalamide, 9,10-bis (4-aminophenyl) anthracene, 4,4′-bis (4-aminophenoxy) diphenylsulfone, 2,2′-bis [4- (4-aminophenoxy) phenyl] propane, 2,2′-bis [4 -(4-aminophenoxy) phenyl] hexafluoropropane, 2,2'-bis (4-aminophenyl) hexafluoropropane, 2,2'-bis (3-aminophenyl) hexafluoropropane, 2,2'- Bis (3-amino-4-methylphenyl) hexafluoropropane, 2,2′-bis (4-aminophenyl) propane, 2,2′-bis (3-aminophenyl) propane, 2,2′-bis ( 3-amino-4-methylphenyl) propane, 1,3-bis (4-aminophenoxy) propane, 1,3-bis (3-aminophenoxy) propa 1,4-bis (4-aminophenoxy) butane, 1,4-bis (3-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) pentane, 1,5-bis (3-aminophenoxy) ) Pentane, 1,6-bis (4-aminophenoxy) hexane, 1,6-bis (3-aminophenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1,7- (3 -Aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) octane, 1,8-bis (3-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,9-bis (3-aminophenoxy) nonane, 1,10-bis (4-aminophenoxy) decane, 1,10-bis (3-aminophenoxy) decane, 1,11-bis (4-aminophene) Xyl) undecane, 1,11-bis (3-aminophenoxy) undecane, 1,12-bis (4-aminophenoxy) dodecane, 1,12-bis (3-aminophenoxy) dodecane, bis (4-aminocyclohexyl) Methane, bis (4-amino-3-methylcyclohexyl) methane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, and the like.

Other diamine compounds include those having an alkyl group, a fluorine-containing alkyl group, an aromatic ring, an aliphatic ring or a heterocyclic ring in the diamine side chain, and those having a macrocyclic substituent composed of these. It can be used as long as the effect is not impaired. Specifically, diamine compounds represented by the following formulas [DA1] to [DA13] can be exemplified.

(In the formulas [DA1] to [DA6], A ¹ represents —COO—, —OCO—, —CONH—, —NHCO—, —CH ₂ —, —O—, —CO— or —NH—, A ² represents a linear or branched alkyl group having 1 to 22 carbon atoms or a linear or branched fluorine-containing alkyl group having 1 to 22 carbon atoms).

(In the formula [DA7], p represents an integer of 1 to 10).

(In the formula [DA10], m represents an integer of 0 to 3, and in the formula [DA13], n represents an integer of 1 to 5).

Furthermore, a diamine compound represented by the following formula [DA14] can also be used as long as the effects of the present invention are not impaired.

(In the formula [DA14], A ¹ represents —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CH ₂ O—, —OCO—, —CON (CH ₃ ). A divalent organic group selected from — or —N (CH ₃ ) CO—, and A ² is a single bond, an aliphatic hydrocarbon group having 1 to 20 carbon atoms, a non-aromatic cyclic hydrocarbon group or an aromatic group. A ³ is a hydrocarbon group, A ³ is a single bond, —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —COO—, —OCO—, —CON (CH ₃ ) —, —N (CH ₃ ) CO— or —O (CH ₂ ) _m — (m is an integer of 1 to 5), A ⁴ is a nitrogen-containing aromatic heterocycle, and n is 1 to 4 is an integer).

In addition, as other diamine compounds, diamine compounds represented by the following formula [DA15] and formula [DA16] can also be used.

As the other diamine compound, a diamine compound represented by the following formula [DA17] can also be used.

(In the formula [DA17], X ₁ and X ₂ each independently represent an H atom, a methyl group or an ethyl group, and m represents an integer of 1 to 3).

Specific examples of the structure of the diamine compound represented by the formula [DA17] are shown below, but are not limited to these examples.

That is, examples of the diamine compound represented by the formula [DA17] include diamine compounds having structures represented by the following formulas [DA17-1] to [DA17-6].

The above-mentioned other diamine compounds have characteristics such as solubility of the specific polymer of the present invention in a solvent, coating properties of a liquid crystal aligning agent, liquid crystal alignment properties, voltage holding ratio, and accumulated charge when used as a liquid crystal alignment film. Depending on the case, one kind or a mixture of two or more kinds may be used.

<Specific polymer>
The specific polymer contained in the liquid crystal aligning agent of the present invention is a diamine having the tetracarboxylic acid component containing the tetracarboxylic dianhydride represented by the formula [1] and a side chain represented by the formula [2]. It is at least one polymer selected from a polyimide precursor obtained by reacting the diamine component containing a compound and a polyimide obtained by imidizing the polyimide precursor.

A polyimide obtained by reacting the tetracarboxylic acid component containing a tetracarboxylic dianhydride represented by the formula [1] with the diamine component containing a diamine compound having a side chain represented by the formula [2] The precursor has a structure represented by the following formula [A], for example.

(In Formula [A], R ¹ is a tetravalent organic group derived from a tetracarboxylic acid component, R ² is a divalent organic group derived from a diamine component, and A ¹ and A ² are hydrogen atoms or Represents an alkyl group having 1 to 8 carbon atoms, which may be the same or different, and A ³ and A ⁴ represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an acetyl group, and are the same. Or n may be different, and n represents a positive integer).

The specific polymer contained in the liquid crystal aligning agent of the present invention is relatively simple by using a tetracarboxylic acid component represented by the following formula [B] and a diamine compound represented by the following formula [C] as raw materials. From the reason that it is obtained, a polyamic acid having a structural formula of a repeating unit represented by the following formula [D] or a polyimide obtained by imidizing the polyamic acid is preferable.

(In formula [B] and formula [C], R ¹ and R ² are as defined in formula [A]).

(In formula [D], R ¹ and R ² have the same meaning as defined in formula [A]).

In addition, the polymer of the formula [D] obtained above is added to the alkyl group having 1 to 8 carbon atoms of A ¹ and A ^{2 represented by} the formula [A] and the formula [A] by a usual synthesis method. It is also possible to introduce an alkyl group having 1 to 5 carbon atoms or an acetyl group of A ³ and A ⁴ shown.

<Method for producing specific polymer>
In the present invention, the specific polymer is obtained by reacting the diamine component with the tetracarboxylic acid component. Specifically, a method of obtaining a polyamic acid by polycondensation of a tetracarboxylic dianhydride and a diamine component, a method of obtaining a polyamic acid by a dehydration polycondensation reaction of a tetracarboxylic acid and a diamine component, or a dicarboxylic acid dihalide and A method of obtaining polyamic acid by polycondensation with a diamine component is used.

Polyamide acid alkyl ester is obtained by polycondensation of a carboxylic acid group dialkyl esterified tetracarboxylic acid and a diamine component, a dicarboxylic ester dicarboxylic ester dicarboxylic acid dihalide and a diamine component. Or the method of converting the carboxyl group of a polyamic acid into ester is used.

In order to obtain polyimide, a method is used in which the polyamic acid or polyamic acid alkyl ester is cyclized to form polyimide.

The reaction between the diamine component and the tetracarboxylic acid component is usually carried out with the diamine component and the tetracarboxylic acid component in an organic solvent. The organic solvent used at that time is not particularly limited as long as the produced polyimide precursor is dissolved. Although the specific example of the organic solvent used for reaction below is given, it is not limited to these examples.

For example, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, 1,3-dimethyl-imidazolidinone, methyl ethyl ketone , Cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, and solvents represented by the following formulas [D-1] to [D-3].

These may be used alone or in combination. Furthermore, even if it is a solvent which does not dissolve a polyimide precursor, you may mix and use the said solvent in the range which the produced | generated polyimide precursor does not precipitate. Moreover, since the water | moisture content in an organic solvent inhibits a polymerization reaction, and also causes the produced polyimide precursor to hydrolyze, it is preferable to use what dehydrated and dried the organic solvent.

When the diamine component and the tetracarboxylic acid component are reacted in an organic solvent, the solution in which the diamine component is dispersed or dissolved in the organic solvent is stirred, and the tetracarboxylic acid component is dispersed or dissolved in the organic solvent as it is. And a method of adding a diamine component to a solution obtained by dispersing or dissolving a tetracarboxylic acid component in an organic solvent, a method of alternately adding a diamine component and a tetracarboxylic acid component, etc. Any of these methods may be used. In addition, when reacting using a plurality of diamine components or tetracarboxylic acid components, they may be reacted in a premixed state, individually or sequentially, or further individually reacted low molecular weight substances. May be mixed and reacted to form a polymer. In this case, the polymerization temperature can be selected from -20 ° C to 150 ° C, but is preferably in the range of -5 ° C to 100 ° C. The reaction can be carried out at any concentration, but if the concentration is too low, it is difficult to obtain a high molecular weight polymer, and if the concentration is too high, the viscosity of the reaction solution becomes too high and uniform stirring is difficult. It becomes. Therefore, it is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. The initial stage of the reaction is carried out at a high concentration, and then an organic solvent can be added.

In the polymerization reaction of the polyimide precursor, the ratio of the total number of moles of the diamine component to the total number of moles of the tetracarboxylic acid component is preferably 0.8 to 1.2. Similar to a normal polycondensation reaction, the molecular weight of the polyimide precursor produced increases as the molar ratio approaches 1.0.

The polyimide of the present invention is a polyimide obtained by ring closure of the polyimide precursor, and in this polyimide, the ring closure rate of the amic acid group (also referred to as imidization rate) is not necessarily 100%. It can be arbitrarily adjusted according to the purpose.

Examples of the method for imidizing the polyimide precursor include thermal imidization in which the polyimide precursor solution is heated as it is or catalytic imidization in which a catalyst is added to the polyimide precursor solution.

When the polyimide precursor is thermally imidized in a solution, the temperature is 100 ° C. to 400 ° C., preferably 120 ° C. to 250 ° C., and it is preferable to carry out while removing water generated by the imidation reaction from the system.

The catalyst imidation of the polyimide precursor can be performed by adding a basic catalyst and an acid anhydride to the polyimide precursor solution and stirring at -20 to 250 ° C, preferably 0 to 180 ° C. The amount of the basic catalyst is 0.5 to 30 mol times, preferably 2 to 20 mol times of the amic acid group, and the amount of the acid anhydride is 1 to 50 mol times, preferably 3 to 30 mol of the amido acid group. Is double. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among them, pyridine is preferable because it has a basicity appropriate for advancing the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, and the like. Among them, use of acetic anhydride is preferable because purification after completion of the reaction is facilitated. The imidization rate by catalytic imidation can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.

When recovering the produced polyimide precursor or polyimide from the polyimide precursor or polyimide reaction solution, the reaction solution may be poured into a solvent and precipitated. Examples of the solvent used for precipitation include methanol, ethanol, isopropyl alcohol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, and water. The polymer precipitated in the solvent can be collected by filtration, and then dried by normal temperature or reduced pressure at room temperature or by heating. In addition, when the polymer collected by precipitation is redissolved in an organic solvent and reprecipitation and collection is repeated 2 to 10 times, impurities in the polymer can be reduced. Examples of the solvent at this time include alcohols, ketones, and hydrocarbons, and it is preferable to use three or more kinds of solvents selected from these because purification efficiency is further increased.

The molecular weight of the specific polymer contained in the liquid crystal alignment treatment agent of the present invention is GPC (Gel Permeation Chromatography) in consideration of the strength of the liquid crystal alignment film obtained therefrom, workability at the time of forming the liquid crystal alignment film, and coating properties. The weight average molecular weight measured by the method is preferably 5,000 to 1,000,000, and more preferably 10,000 to 150,000.

<Liquid crystal alignment agent>
The liquid crystal aligning agent of the present invention is a coating solution for forming a liquid crystal alignment film, and contains a polymer component and a solvent, and is a coating solution for forming a polymer film.

And as above-mentioned, the liquid-crystal aligning agent of this invention is a tetracarboxylic-acid component containing the said specific polymer, ie, the tetracarboxylic dianhydride shown by said Formula [1], as a polymer component, and At least one polymer selected from a polyimide precursor obtained by reacting a diamine component containing a diamine compound having a side chain represented by the above formula [2] and a polyimide obtained by imidizing the polyimide precursor The present invention has a structure in which physical stress on the liquid crystal alignment film during liquid crystal dropping is reduced and has a structure with high hydrophobicity, as shown in the examples described later. A liquid crystal display device comprising a liquid crystal alignment film obtained by using the liquid crystal alignment treatment agent should have improved alignment unevenness and excellent heat resistance at a pretilt angle. Kill.

More specifically, it is considered that the alignment unevenness of the liquid crystal display element is caused by physical stress applied to the liquid crystal alignment film when the liquid crystal is dropped by the ODF method and the vertical alignment of the liquid crystal is lowered. Also, adsorbed water and impurities adhering to the surface of the liquid crystal alignment film are swept away by the liquid crystal dropped in the ODF process, and the amount of adsorbed water and impurities is different at the liquid crystal dropping part and the part where the liquid crystal droplets are in contact with each other. This is considered to occur. Here, the ODF method refers to dropping liquid crystal directly onto a liquid crystal alignment film formed on a substrate.

Since the specific polymer contained in the liquid crystal aligning agent of the present invention has a methylene group derived from the tetracarboxylic dianhydride represented by the formula [1] in the main chain, it is flexible and has a liquid crystal alignment. When the treatment agent is applied to the substrate, the specific polymer easily moves to the surface layer (that is, the side opposite to the substrate) of the coating film (and thus the liquid crystal alignment film). And since this specific polymer has the side chain shown by Formula [2] derived from the diamine compound which has a side chain shown by Formula [2], in the surface layer of a coating film or a liquid crystal aligning film, it is Formula [2]. The density of the side chain indicated by increases. As described above, the specific polymer moves to the surface layer, and the density of the side chain represented by the formula [2] on the surface layer is increased, thereby reducing physical stress on the liquid crystal alignment film at the time of liquid crystal dropping. The

Then, the specific polymer migrates to the surface layer and the density of the side chain represented by the formula [2] on the surface layer increases, so that the hydrophobicity of the liquid crystal alignment film increases. Furthermore, by using the tetracarboxylic dianhydride represented by the formula [1], thermal imidization that occurs when the liquid crystal alignment treatment agent is applied to the substrate and then baked easily proceeds, and the hydrophobicity of the liquid crystal alignment film is increased. Get higher. Thus, since it is highly hydrophobic, the amount of adsorbed water and impurities in the liquid crystal dropping part can be made uniform.

As a result, it is presumed that the alignment unevenness generated by the ODF method can be improved.

In particular, in the PSA mode, when a liquid crystal containing a monomer (polymerizable compound) is dropped onto the liquid crystal alignment film by the ODF method, a monomer separation phenomenon (also referred to as a chromatographic phenomenon) occurs when the liquid crystal spreads. When the PSA treatment is performed, regions having different pretilt angles of the liquid crystal are generated, and alignment unevenness is likely to occur. Here, PSA is a liquid crystal display element of a method (vertical alignment method) in which liquid crystal molecules aligned perpendicular to a substrate are responded by an electric field (polymeric compound is previously added to the liquid crystal composition). Say. The polymerizable compound refers to a compound that is polymerized by at least one of active energy rays and heat.

Even in such a PSA mode, according to the liquid crystal aligning agent of the present invention, since the hydrophobicity is high, the dispersibility of the monomer can be made uniform, and variation in the pretilt angle can be suppressed, Uneven alignment can be improved.

In addition, when the specific polymer moves to the surface layer and the density of the side chain represented by the formula [2] on the surface layer increases, the side chain represented by the formula [2] becomes stable, and the heat resistance of the pretilt angle is improved. Presumably improved.

And the liquid crystal aligning agent of this invention is excellent in printability, and can obtain the uniform coating film without a repellency and film thickness nonuniformity.

A liquid crystal display element having a liquid crystal alignment film produced using the liquid crystal alignment treatment agent of the present invention has no alignment defect due to alignment unevenness and is excellent in thermal stability of a pretilt angle. A liquid crystal display element with excellent quality and high reliability is obtained.

All the polymer components in the liquid crystal aligning agent of the present invention may be all specific polymers, or other polymers may be mixed. In that case, the content of the other polymer is 0.5 mass% to 15 mass%, preferably 1 mass% to 10 mass% of the specific polymer. Other polymers include polyimide precursors or polyimides that do not use the tetracarboxylic dianhydride represented by the formula [1]. Furthermore, an acrylic polymer, a methacrylic polymer, polystyrene, polyamide, polysiloxane, etc. are mentioned.

The solid content concentration in the liquid crystal alignment treatment agent of the present invention can be appropriately changed depending on the thickness of the liquid crystal alignment film to be formed, but is preferably 0.5 to 10% by mass, and preferably 1 to 8% by mass. More preferably. If the solid content concentration is less than 0.5% by mass, it is difficult to form a uniform and defect-free coating film, and if it exceeds 10% by mass, the storage stability of the solution may be deteriorated. The term “solid content” as used herein refers to a component obtained by removing the solvent from the liquid crystal aligning agent, and means the above-described specific polymer, other polymers, and various additives described later.

The organic solvent in the liquid crystal alignment treatment agent of the present invention preferably has an organic solvent content of 70 to 99.9% by mass from the viewpoint of forming a uniform liquid crystal alignment film by coating. This content can be appropriately changed depending on the film thickness of the target liquid crystal alignment film.

The organic solvent used in the liquid crystal aligning agent of the present invention is not particularly limited as long as it is an organic solvent (also referred to as a good solvent) that dissolves the specific polymer. Although the specific example of a good solvent is given to the following, it is not limited to these examples.

For example, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, 1,3-dimethyl-imidazolidinone, methyl ethyl ketone Cyclohexanone, cyclopentanone or 4-hydroxy-4-methyl-2-pentanone. Among these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, the solvents represented by the above formulas [D-1] to [D-3], and the like can be given. These may be used alone or in combination.

Of these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, and γ-butyrolactone are preferably used. Furthermore, when the solubility of the specific polymer in the solvent is high, it is preferable to use the solvents represented by the formulas [D-1] to [D-3].

The good solvent in the liquid crystal aligning agent of the present invention is preferably 10 to 100% by mass of the total solvent contained in the liquid crystal aligning agent. Of these, 20 to 90% by mass is preferable. More preferred is 30 to 80% by mass.

Unless the effect of this invention is impaired, the liquid-crystal aligning agent of this invention is an organic solvent (it is also called a poor solvent) which improves the coating property and surface smoothness of a liquid-crystal aligning film at the time of apply | coating a liquid-crystal aligning agent. Can be used. Although the specific example of a poor solvent is given to the following, it is not limited to these examples.

For example, ethanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, isopentyl alcohol, tert-pentyl alcohol, 3-methyl-2-butanol, neopentyl alcohol, 1-hexanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-ethyl-1-butanol, 1-heptanol 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, cyclohexanol, 1-methylcyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol, 1,2- Ethane All, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol 2-methyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, dipropyl ether, dibutyl ether, dihexyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1 , 2-butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 2-pentanone, 3-pentanone, 2-hexanone, -Heptanone, 4-heptanone, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene Carbonate, 2- (methoxymethoxy) ethanol, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, 2- (hexyloxy) ethanol, furfuryl alcohol, diethylene glycol, propylene glycol, propylene glycol monobutyl ether, 1 -(Butoxyethoxy) propanol, propylene glycol monomethyl ether acetate, dipropylene glycol , Dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monoacetate, ethylene glycol Diacetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2- (2-ethoxyethoxy) ethyl acetate, diethylene glycol acetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, Methyl lactate, ethyl lactate, methyl acetate, acetic acid Chill, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate or the above formula [D -1] to a solvent represented by the formula [D-3].

Among them, 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether or ethylene glycol monobutyl ether, or the above-mentioned formulas [D-1] to [D-3] It is preferable to use a solvent represented by

These poor solvents are preferably 1 to 70% by mass of the whole organic solvent contained in the liquid crystal aligning agent. Among these, 1 to 60% by mass is preferable. More preferred is 5 to 60% by mass.

The liquid crystal aligning agent of the present invention comprises a crosslinkable compound having an epoxy group, an isocyanate group, an oxetane group or a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group and a lower alkoxyalkyl group, unless the effects of the present invention are impaired. A crosslinkable compound having at least one substituent selected from the group or a crosslinkable compound having a polymerizable unsaturated bond may be contained. It is necessary to have two or more of these substituents and polymerizable unsaturated bonds in the crosslinkable compound.

Examples of the crosslinkable compound having an epoxy group or an isocyanate group include bisphenolacetone glycidyl ether, phenol novolac epoxy resin, cresol novolac epoxy resin, triglycidyl isocyanurate, tetraglycidylaminodiphenylene, tetraglycidyl-m-xylenediamine, tetra Glycidyl-1,3-bis (aminoethyl) cyclohexane, tetraphenyl glycidyl ether ethane, triphenyl glycidyl ether ethane, bisphenol hexafluoroacetodiglycidyl ether, 1,3-bis (1- (2,3-epoxypropoxy)- 1-trifluoromethyl-2,2,2-trifluoromethyl) benzene, 4,4-bis (2,3-epoxypropoxy) octafluorobiphenyl , Triglycidyl-p-aminophenol, tetraglycidylmetaxylenediamine, 2- (4- (2,3-epoxypropoxy) phenyl) -2- (4- (1,1-bis (4- (2,3- Epoxypropoxy) phenyl) ethyl) phenyl) propane or 1,3-bis (4- (1- (4- (2,3-epoxypropoxy) phenyl) -1- (4- (1- (4- (2, And 3-epoxypropoxy) phenyl) -1-methylethyl) phenyl) ethyl) phenoxy) -2-propanol.

The crosslinkable compound having an oxetane group is a crosslinkable compound having at least two oxetane groups represented by the following formula [4].

Specific examples include crosslinkable compounds represented by the formulas [4a] to [4k] published on pages 58 to 59 of International Publication No. WO2011 / 132751.

The crosslinkable compound having a cyclocarbonate group is a crosslinkable compound having at least two cyclocarbonate groups represented by the following formula [5].

Specifically, the crosslinkable compounds represented by the formulas [5-1] to [5-42] described on pages 76 to 82 of International Publication No. WO2011 / 132751 may be mentioned.

Examples of the crosslinkable compound having at least one substituent selected from the group consisting of a hydroxyl group and an alkoxyl group include an amino resin having a hydroxyl group or an alkoxyl group, such as a melamine resin, a urea resin, a guanamine resin, and a glycoluril. -Formaldehyde resin, succinilamide-formaldehyde resin or ethylene urea-formaldehyde resin. Specifically, a melamine derivative, a benzoguanamine derivative, or glycoluril in which a hydrogen atom of an amino group is substituted with a methylol group or an alkoxymethyl group or both can be used. The melamine derivative or benzoguanamine derivative can exist as a dimer or a trimer. These preferably have an average of 3 to 6 methylol groups or alkoxymethyl groups per triazine ring.

Examples of such melamine derivatives or benzoguanamine derivatives include MX-750, which has an average of 3.7 substituted methoxymethyl groups per triazine ring, and an average of 5. methoxymethyl groups per triazine ring. Eight-substituted MW-30 (Sanwa Chemical Co., Ltd.) and Cymel 300, 301, 303, 350, 370, 771, 325, 327, 703, 712 and other methoxymethylated melamines, Cymel 235, 236 Methoxymethylated butoxymethylated melamine such as 238, 212, 253, and 254, butoxymethylated melamine such as Cymel 506 and 508, carboxyl group-containing methoxymethylated isobutoxymethylated melamine such as Cymel 1141, Cymel 1123 and the like Methoxymethylated eth Cymethylated benzoguanamine, methoxymethylated butoxymethylated benzoguanamine such as Cymel 1123-10, butoxymethylated benzoguanamine such as Cymel 1128, carboxyl group-containing methoxymethylated ethoxymethylated benzoguanamine such as Cymel 1125-80 Cyanamide). Examples of glycoluril include butoxymethylated glycoluril such as Cymel 1170, methylolated glycoluril such as Cymel 1172, and methoxymethylolated glycoluril such as Powderlink 1174.

Examples of the benzene or phenolic compound having a hydroxyl group or an alkoxyl group include 1,3,5-tris (methoxymethyl) benzene, 1,2,4-tris (isopropoxymethyl) benzene, 1,4-bis ( sec-butoxymethyl) benzene or 2,6-dihydroxymethyl-p-tert-butylphenol.

More specifically, there are crosslinkable compounds represented by the formulas [6-1] to [6-48], which are listed on pages 62 to 66 of International Publication No. WO2011 / 132751.

Examples of the crosslinkable compound having a polymerizable unsaturated bond include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, and tri (meth) acryloyloxyethoxytrimethylol. Crosslinkable compounds having three polymerizable unsaturated groups in the molecule such as propane or glycerin polyglycidyl ether poly (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (Meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol Di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene oxide bisphenol A type di (meth) acrylate, propylene oxide bisphenol type di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, glycerin Di (meth) acrylate, pentaerythritol di (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, diglycidyl phthalate di (meth) acrylate or hydroxypivalic acid neo Crosslinkable compounds having two polymerizable unsaturated groups in the molecule, such as pentyl glycol di (meth) acrylate, in addition to 2-hydroxyethyl (meth) acrylate 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropyl phthalate, 3-chloro -One polymerizable unsaturated group such as 2-hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) acryloyloxyethyl phosphate ester or N-methylol (meth) acrylamide in the molecule A crosslinkable compound is mentioned.

In addition, a compound represented by the following formula [7] can also be used.

(In the formula [7], E ₁ represents a group selected from the group consisting of a cyclohexane ring, a bicyclohexane ring, a benzene ring, a biphenyl ring, a terphenyl ring, a naphthalene ring, a fluorene ring, an anthracene ring or a phenanthrene ring; ₂ represents a group selected from the following formula [7a] or [7b], and n represents an integer of 1 to 4.

The above compound is an example of a crosslinkable compound and is not limited thereto. Moreover, the crosslinkable compound used for the liquid-crystal aligning agent of this invention may be 1 type, and may be combined 2 or more types.

In the liquid crystal aligning agent of the present invention, the content of the crosslinkable compound is preferably 0.1 to 150 parts by mass with respect to 100 parts by mass of all polymer components. In order for the crosslinking reaction to proceed and to achieve the desired effect, the amount is more preferably 0.1 to 100 parts by weight, and most preferably 1 to 50 parts by weight, based on 100 parts by weight of all polymer components.

When a liquid crystal alignment film is formed using the liquid crystal alignment treatment agent of the present invention, as a compound that promotes charge transfer in the liquid crystal alignment film and promotes charge release of a liquid crystal cell using the liquid crystal alignment film, International Publication No. WO 2011 It is preferable to add nitrogen-containing heterocyclic amine compounds represented by the formulas [M1] to [M156], which are described on pages 69 to 73 of / 132751. This amine compound may be added directly to the composition, but it may be added after a solution having a concentration of 0.1% by mass to 10% by mass, preferably 1% by mass to 7% by mass with an appropriate solvent. preferable. The solvent is not particularly limited as long as it is an organic solvent that dissolves the specific polymer described above.

For the liquid crystal alignment treatment agent of the present invention, a compound that improves the uniformity of the film thickness and surface smoothness of the liquid crystal alignment film when the liquid crystal alignment treatment agent is applied can be used as long as the effects of the present invention are not impaired. Furthermore, a compound that improves the adhesion between the liquid crystal alignment film and the substrate can also be used.

Examples of compounds that improve the film thickness uniformity and surface smoothness of the liquid crystal alignment film include fluorine-based surfactants, silicone-based surfactants, and nonionic surfactants.

More specifically, for example, F-top EF301, EF303, EF352 (above, manufactured by Tochem Products), MegaFuck F171, F173, R-30 (above, manufactured by Dainippon Ink, Inc.), Florard FC430, FC431 (or above) Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (above, manufactured by Asahi Glass Co., Ltd.). The use ratio of these surfactants is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass with respect to 100 parts by mass of all the polymer components contained in the liquid crystal aligning agent. It is.

Specific examples of the compound that improves the adhesion between the liquid crystal alignment film and the substrate include the following functional silane-containing compounds and epoxy group-containing compounds.

For example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxy Carbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10- Riethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyl Trimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3- Aminopropyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether Polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6- Tetraglycidyl-2,4-hexanediol, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane or N, N, N Examples include ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane.

When using a compound to be adhered to these substrates, the amount is preferably 0.1 to 30 parts by weight, more preferably 1 to 30 parts by weight with respect to 100 parts by weight of all polymer components contained in the liquid crystal aligning agent. 20 parts by mass. If it is less than 0.1 part by mass, the effect of improving the adhesion cannot be expected, and if it exceeds 30 parts by mass, the storage stability of the liquid crystal aligning agent may be deteriorated.

The liquid crystal alignment treatment agent of the present invention includes the above poor solvent, a crosslinkable compound, a compound that improves the film thickness uniformity and surface smoothness of the liquid crystal alignment film, and a compound that adheres to the substrate. As long as the effect is not impaired, a dielectric material or conductive material for changing the electrical characteristics such as the dielectric constant and conductivity of the liquid crystal alignment film may be added.

<Liquid crystal alignment film and liquid crystal display element>
The liquid crystal alignment treatment agent of the present invention can be used as a liquid crystal alignment film after being applied and baked on a substrate and then subjected to alignment treatment by rubbing treatment or light irradiation. In the case of vertical alignment, etc., it can be used as a liquid crystal alignment film without alignment treatment. The substrate used at this time is not particularly limited as long as it is a highly transparent substrate. In addition to a glass substrate, a plastic substrate such as an acrylic substrate or a polycarbonate substrate can also be used. From the viewpoint of simplification of the process, it is preferable to use a substrate on which an ITO electrode for driving a liquid crystal is formed. In the reflective liquid crystal display element, an opaque substrate such as a silicon wafer can be used if only one substrate is used, and a material that reflects light such as aluminum can be used as an electrode in this case.

The method for applying the liquid crystal aligning agent is not particularly limited, but industrially, a method of screen printing, offset printing, flexographic printing, an inkjet method, or the like is generally used. Examples of other coating methods include a dipping method, a roll coater method, a slit coater method, a spinner method, and a spray method, and these may be used depending on the purpose.

After applying the liquid crystal aligning agent on the substrate, it is preferably 30 to 300 ° C., depending on the solvent used for the liquid crystal aligning agent, by a heating means such as a hot plate, a thermal circulation oven or an IR (infrared) oven. The liquid crystal alignment film can be obtained by evaporating the solvent at a temperature of 30 to 250 ° C. If the thickness of the liquid crystal alignment film after baking is too thick, it is disadvantageous in terms of power consumption of the liquid crystal display element, and if it is too thin, the reliability of the liquid crystal display element may be lowered. Is 10 to 100 nm. When the liquid crystal is horizontally aligned or tilted, the fired liquid crystal alignment film is treated by rubbing or irradiation with polarized ultraviolet rays.

The liquid crystal display element of the present invention is a liquid crystal display element obtained by obtaining a substrate with a liquid crystal alignment film from the liquid crystal alignment treatment agent of the present invention by the above-described method and then preparing a liquid crystal cell by a known method. For example, two substrates arranged to face each other, a liquid crystal layer provided between the substrates, and a liquid crystal alignment treatment agent of the present invention provided between the substrate and the liquid crystal layer. A liquid crystal display device comprising a liquid crystal cell having the liquid crystal alignment film. As such a liquid crystal display element of the present invention, a vertical alignment (VA) method, a horizontal alignment (IPS: In-Plane Switching) method, a twisted nematic (TN) method, an OCB alignment (OCB). Various methods such as an Optically Compensated Bend (PB) method may be used, and a PSA (Polymer Sustained Alignment) method may be used. Note that the liquid crystal alignment film only needs to be provided on at least one of the two substrates.

As a method for manufacturing a liquid crystal cell, prepare a pair of substrates on which a liquid crystal alignment film is formed, spray spacers on the liquid crystal alignment film on one substrate, and place the liquid crystal alignment film surface on the other side. And a method of sealing the substrate by injecting liquid crystal under reduced pressure, or a method of sealing the substrate by bonding the substrate after dropping the liquid crystal on the liquid crystal alignment film surface on which the spacers are dispersed. As described above, in the ODF method, alignment unevenness is likely to occur. However, by using the liquid crystal aligning agent of the present invention, the occurrence of alignment unevenness can be suppressed even in the ODF method.

When manufacturing a PSA type liquid crystal display element, there is a step of irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film or liquid crystal layer of the liquid crystal cell. A PSA-type liquid crystal display element uses a liquid crystal material (liquid crystal composition) in which a liquid crystal is mixed with a polymerizable compound that is polymerized by at least one of active energy rays and heat, and ultraviolet rays are applied while applying a voltage to a liquid crystal cell. It is obtained by irradiation.

Examples of the polymerizable compound include a polymerizable compound having a photopolymerizable group at each of two ends as represented by the following formula (III), and a photopolymerizable group represented by the following formula (IV). And a polymerizable compound having a photocrosslinkable group and a polymerizable compound having a photocrosslinkable group at each of two terminals represented by the following formula (V). In the following formulas (III) to (V), R ¹² is H or an alkyl group having 1 to 4 carbon atoms, and Z ¹ is an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms. An optionally substituted divalent aromatic ring or heterocyclic ring, Z ² is a monovalent aromatic ring or heterocyclic ring, and the monovalent aromatic ring or heterocyclic ring is an alkyl group having 1 to 12 carbon atoms and It may be substituted with one or more substituents selected from alkoxy groups having 1 to 12 carbon atoms, and Q ¹ is a divalent organic group. Q ¹ has a ring structure such as a phenylene group (—C ₆ H ₄ —), a biphenylene group (—C ₆ H ₄ —C ₆ H ₄ —), a cyclohexylene group (—C ₆ H ₁₀ —), and the like. Preferably it is. This is because the interaction with the liquid crystal tends to increase.

Specific examples of the polymerizable compound represented by the formula (III) include the following polymerizable compounds. In the formula, V represents a single bond or —R ¹⁹ O—, and R ¹⁹ represents a linear or branched alkylene group having 1 to 10 carbon atoms, and preferably represents —R ¹⁹ O— and R ¹⁹ represents A linear or branched alkylene group having 2 to 6 carbon atoms. W represents a single bond or —OR ²⁰ — and R ²⁰ represents a linear or branched alkylene group having 1 to 10 carbon atoms, and preferably represents —OR ²⁰ — and R ²⁰ represents a linear or A branched alkylene group having 2 to 6 carbon atoms. V and W may be the same or different, but if they are the same, synthesis is easy.

Also, other specific examples of the polymerizable compound represented by the formula (III) include polymerizable compounds of the following formula.

(In the formula, V represents a single bond or —R ¹⁹ O—, and R ¹⁹ represents a linear or branched alkylene group having 1 to 10 carbon atoms, preferably represented by —R ¹⁹ O— and represented by R ¹⁹ Is a linear or branched alkylene group having 2 to 6 carbon atoms, W is a single bond or —OR ²⁰ —, and R ²⁰ is a linear or branched alkylene group having 1 to 10 carbon atoms. preferably, ^{-OR 20} - synthesis and is represented by R ²⁰ .V and W is a linear or branched alkylene group having 2 to 6 carbon atoms may be the same or different structure but the same R ¹² is H or an alkyl group having 1 to 4 carbon atoms.)

The production method of such a polymerizable compound is not particularly limited. For example, the polymerizable compound represented by the following formula (1) can be synthesized by combining techniques in organic synthetic chemistry. For example, Taraga and the like represented by the following reaction formula can use 2- (bromomethyl) acrylic acid with SnCl _{2 according} to the method proposed by P. Talaga, M. Schaeffer, C. Benezra and JLStampf, Synthesis, 530 (1990). It can be synthesized by reacting (2- (bromomethyl) propenic acid) with an aldehyde or a ketone. Amberlyst 15 is a strongly acidic ion exchange resin manufactured by Rohm and Haas.

(In the formula, R ′ represents a monovalent organic group.)

In addition, 2- (bromomethyl) acrylic acid is represented by the following reaction formula: K. Ramarajan, K. Kamalingam, DJO'Donnell and KDBerlin, Organic Synthesis, vol. 61, 56-59 (1983) It can be synthesized by the method proposed in.

As a specific synthesis example, when synthesizing a polymerizable compound represented by the above formula (1) in which V is —R ¹ O—, W is —OR ² —, and R ¹ and R ² are the same, There are two methods shown in the following reaction formula.

Moreover, when synthesizing the polymerizable compound represented by the above formula (1) in which R ¹⁹ and R ²⁰ are different, a method represented by the following reaction formula is exemplified.

And when synthesize | combining the polymeric compound represented by the said Formula (1) whose V and W are single bonds, the method shown by following Reaction Formula is mentioned.

The step of producing a liquid crystal cell by irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film or the liquid crystal layer (PSA treatment) is performed by applying a voltage between electrodes placed on a substrate, for example. And a method of applying an electric field to the liquid crystal layer and irradiating ultraviolet rays while maintaining the electric field. Here, the voltage applied between the electrodes is, for example, 5 to 30 Vp-p, preferably 5 to 20 Vp-p. The irradiation amount of ultraviolet rays is, for example, 1 to 60 J, preferably 40 J or less, and the smaller the irradiation amount of ultraviolet rays, the lowering of reliability caused by the destruction of the members constituting the liquid crystal display element can be suppressed, and the irradiation time of ultraviolet rays can be reduced. This is preferable because the manufacturing efficiency is improved. In addition, the wavelength of the irradiated ultraviolet light is, for example, 200 nm to 400 nm.

Thus, when ultraviolet rays are applied while applying a voltage to the liquid crystal alignment film or the liquid crystal layer, the polymerizable compound reacts to form a polymer, and the direction in which the liquid crystal molecules are tilted is stored by this polymer. The response speed of the obtained liquid crystal display element can be increased.

In the PSA method, when a liquid crystal containing a monomer (polymerizable compound) is dropped on the liquid crystal alignment film by the ODF method, a separation phenomenon of the monomer occurs when the liquid crystal spreads. When the PSA treatment is performed in this state, the liquid crystal However, in the liquid crystal display element of the present invention, since the liquid crystal aligning agent of the present invention is used, the alignment unevenness is suppressed.

In the above description, the PSA type liquid crystal display element manufactured by adding a polymerizable compound to the liquid crystal forming the liquid crystal alignment film has been described. However, the liquid crystal display element of the present invention has an active energy ray and a heat It may be prepared by containing a component containing a polymerizable group that is polymerized by at least one of the above (SC-PVA method). The component containing a polymerizable group that is polymerized by at least one of active energy rays and heat is a polymerizable compound that is the same as that in the PSA system, or a polymer that contains a polymerizable group that is polymerized by at least one of active energy rays and heat. . In the case of such an SC-PVA method, there is a step of irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film or liquid crystal layer of the liquid crystal cell, as in the PSA method. As described above, when ultraviolet rays are applied while applying a voltage to the liquid crystal alignment film or the liquid crystal layer, the polymer containing the polymerizable compound or the polymerizable group reacts to form a polymer, and thereby the liquid crystal molecules are inclined. By storing the direction, the response speed of the obtained liquid crystal display element can be increased.

A liquid crystal display element having a liquid crystal alignment film prepared using the liquid crystal alignment treatment agent of the present invention has no alignment defect due to alignment unevenness and is excellent in thermal stability of a pretilt angle. A liquid crystal display element with excellent quality and high reliability is obtained. In particular, it can be suitably used for a large-screen high-definition liquid crystal television.

The present invention will be described in more detail with reference to the following examples, but is not limited thereto.
Abbreviations used in Synthesis Examples, Examples 1 to 15 and Comparative Examples 1 to 5 are as follows.

<Tetracarboxylic acid component>
(Specific tetracarboxylic dianhydride)
A1: Tetracarboxylic dianhydride represented by the following formula [A1]

(Other tetracarboxylic dianhydrides)
A2: 1,2,3,4-cyclobutanetetracarboxylic dianhydride (tetracarboxylic dianhydride represented by the following formula [A2])
A3: Bicyclo [3.3.0] octane-2,4,6,8-tetracarboxylic dianhydride (tetracarboxylic dianhydride represented by the following formula [A3])
A4: Tetracarboxylic dianhydride represented by the following formula [A4] A5: Tetracarboxylic dianhydride represented by the following formula [A5]

<Diamine component>
(Side-chain diamine compound)
B1: 1,3-diamino-4- [4- (trans-4-n-heptylcyclohexyl) phenoxy] benzene (diamine compound represented by the following formula [B1])
B2: 1,3-diamino-5- [4- (trans-4-n-heptylcyclohexyl) phenoxymethyl] benzene (diamine compound represented by the following formula [B2])
B3: 1,3-diamino-4- {4- [trans-4- (trans-4-n-pentylcyclohexyl) cyclohexyl] phenoxy} benzene (diamine compound represented by the following formula [B3])
B4: 1,3-diamino-5- {4- [4- (trans-4-n-pentylcyclohexyl) cyclohexyl] phenoxymethyl} benzene (diamine compound represented by the following formula [B4])
B5: Specific side chain type diamine compound represented by the following formula [B5]

(Other diamine compounds)
C1: m-phenylenediamine (diamine compound represented by the following formula [C1])
C2: p-phenylenediamine (diamine compound represented by the following formula [C2])
C3: 3,5-diaminobenzoic acid (diamine compound represented by the following formula [C3])
C4: Diamine compound represented by the following formula [C4] C5: Diamine compound represented by the following formula [C5] C6: 1,3-diamino-4-octadecyloxybenzene (diamine represented by the following formula [C6] Compound)

<Crosslinkable compound>
D1: YH-434L (manufactured by Tohto Kasei) (epoxy crosslinking compound)
D2: OXT-221 (manufactured by Toa Gosei) (oxetane-based crosslinkable compound)
D3: Crosslinkable compound represented by the following formula (hydroxylated phenol-based crosslinkable compound)

<Organic solvent>
(Polar solvent)
NMP: N-methyl-2-pyrrolidone NEP: N-ethyl-2-pyrrolidone G-BL: γ-butyrolactone

(Other organic solvents)
BCS: 2-butoxyethanol PB: Propylene glycol monobutyl ether

<Measurement of molecular weight of polyimide precursor and polyimide>
The molecular weights of the polyimide precursor and the polyimide in the synthesis example are determined using a room temperature gel permeation chromatography (GPC) apparatus (GPC-101) (manufactured by Showa Denko KK) and a column (KD-803, KD-805) (manufactured by Shodex). The measurement was performed as follows.
Column temperature: 50 ° C
Eluent: N, N′-dimethylformamide (as additives, lithium bromide monohydrate (LiBr · H ₂ O) 30 mmol / L (liter), phosphoric acid / anhydrous crystal (o-phosphoric acid) 30 mmol) / L, 10 ml / L of tetrahydrofuran (THF))
Flow rate: 1.0 ml / min Standard sample for preparing a calibration curve: TSK standard polyethylene oxide (molecular weight: about 900,000, 150,000, 100,000, and 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight; (About 12,000, 4,000, and 1,000) (manufactured by Polymer Laboratory).

<Measurement of imidation ratio of polyimide>
The imidation ratio of polyimide in the synthesis example was measured as follows. 20 mg of polyimide powder was put into an NMR (nuclear magnetic resonance) sample tube (NMR sampling tube standard, φ5 (manufactured by Kusano Kagaku)), and deuterated dimethyl sulfoxide (DMSO-d6, 0.05 mass% TMS (tetramethylsilane)). (Mixed product) (0.53 ml) was added and completely dissolved by applying ultrasonic waves. This solution was measured for proton NMR at 500 MHz with an NMR measuring instrument (JNW-ECA500) (manufactured by JEOL Datum). The imidation rate is determined based on protons derived from structures that do not change before and after imidation as reference protons, and the peak integrated value of these protons and proton peaks derived from NH groups of amic acid appearing in the vicinity of 9.5 ppm to 10.0 ppm. It calculated | required by the following formula | equation using the integrated value.
Imidization rate (%) = (1−α · x / y) × 100

In the above formula, x is a proton peak integrated value derived from NH group of amic acid, y is a peak integrated value of reference proton, α is one NH group proton of amic acid in the case of polyamic acid (imidation rate is 0%) Is the number ratio of the reference proton to.

The polyamic acids and polyimides of Synthesis Examples 1 to 15 are shown in Table 1.

<Synthesis Example 1>
A1 (3.44 g, 16.2 mmol), B1 (3.70 g, 9.73 mmol) and C1 (2.45 g, 22.7 mmol) were mixed in NMP (28.1 g) and reacted at 40 ° C. for 5 hours. After that, A2 (3.18 g, 16.2 mmol) and NMP (23.0 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution (A) having a solid content concentration of 20.0% by mass. Obtained. The number average molecular weight of this polyamic acid was 11,500, and the weight average molecular weight was 38,600.

<Synthesis Example 2>
After adding NMP to the polyamic acid solution (A) (15.0 g) having a solid content concentration of 20.0% by mass obtained in Synthesis Example 1 and diluting to 6% by mass, acetic anhydride (2 .33 g) and pyridine (1.21 g) were added and reacted at 40 ° C. for 3 hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (B). The imidation ratio of this polyimide was 52%, the number average molecular weight was 10,980, and the weight average molecular weight was 33,200.

<Synthesis Example 3>
A1 (3.31 g, 15.6 mmol), B1 (3.56 g, 9.36 mmol) and C4 (2.67 g, 21.8 mmol) were mixed in NMP (27.7 g) and reacted at 40 ° C. for 5 hours. After that, A2 (3.06 g, 15.6 mmol) and NMP (22.7 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution having a solid content concentration of 20.0 mass%.

After adding NMP to the obtained polyamic acid solution (20.5 g) and diluting to 6% by mass, acetic anhydride (2.32 g) and pyridine (1.21 g) were added as imidization catalysts, Reacted for hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (C). The imidation ratio of this polyimide was 72%, the number average molecular weight was 11,800, and the weight average molecular weight was 32,400.

<Synthesis Example 4>
A1 (2.59 g, 12.2 mmol), B3 (3.70 g, 8.56 mmol) and C2 (1.72 g, 15.9 mmol) were mixed in NMP (24.4 g) and reacted at 40 ° C. for 5 hours. After that, A3 (3.06 g, 12.2 mmol) and NMP (19.9 g) were added and reacted at 50 ° C. for 5 hours to obtain a polyamic acid solution having a solid content concentration of 20.0 mass%.

After adding NMP to the obtained polyamic acid solution (15.0 g) and diluting to 6% by mass, acetic anhydride (2.03 g) and pyridine (1.04 g) were added as imidization catalysts, The reaction was allowed for 5 hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (D). The imidation ratio of this polyimide was 51%, the number average molecular weight was 12,100, and the weight average molecular weight was 35,200.

<Synthesis Example 5>
A1 (1.98 g, 9.35 mmol), B2 (4.61 g, 9.35 mmol) and C3 (2.13 g, 14.0 mmol) were mixed in NMP (25.2 g) and reacted at 40 ° C. for 5 hours. After that, A2 (2.75 g, 14.0 mmol) and NMP (20.7 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution having a solid content concentration of 20.0 mass%.

After adding NMP to the obtained polyamic acid solution (15.1 g) and diluting to 6% by mass, acetic anhydride (2.04 g) and pyridine (1.05 g) were added as imidization catalysts, Reacted for hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (E). The imidation ratio of this polyimide was 70%, the number average molecular weight was 13,000, and the weight average molecular weight was 34,200.

<Synthesis Example 6>
A1 (1.34 g, 6.29 mmol), B4 (2.81 g, 6.29 mmol) and C4 (1.79 g, 14.7 mmol) were mixed in NMP (19.4 g) and reacted at 40 ° C. for 5 hours. After that, A2 (2.88 g, 14.7 mmol) and NMP (15.9 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution having a solid content concentration of 20.0 mass%.

After adding NMP to the obtained polyamic acid solution (15.0 g) and diluting to 6% by mass, acetic anhydride (1.01 g) and pyridine (0.79 g) were added as an imidization catalyst, and 1 at 40 ° C. The reaction was allowed for 5 hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (F). The imidation ratio of this polyimide was 52%, the number average molecular weight was 14,200, and the weight average molecular weight was 35,100.

<Synthesis Example 7>
A1 (1.40 g, 6.60 mmol), B5 (3.79 g, 7.70 mmol) and C3 (1.84 g, 12.1 mmol) were mixed in NMP (22.1 g) and reacted at 40 ° C. for 5 hours. After that, A2 (3.02 g, 15.4 mmol) and NMP (18.1 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution having a solid content concentration of 20.0 mass%.

After adding NMP to the obtained polyamic acid solution (15.0 g) and diluting to 6% by mass, acetic anhydride (2.01 g) and pyridine (1.04 g) were added as imidization catalysts, The reaction was allowed for 5 hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (G). The imidation ratio of this polyimide was 53%, the number average molecular weight was 10,800, and the weight average molecular weight was 31,100.

<Synthesis Example 8>
A1 (2.54 g, 12.0 mmol), B1 (4.56 g, 12.0 mmol) and C2 (1.94 g, 18.0 mmol) were mixed in NMP (28.7 g) and reacted at 40 ° C. for 5 hours. After that, A4 (4.03 g, 18.0 mmol) and NMP (28.7 g) were added and reacted at 40 ° C. for 8 hours to obtain a polyamic acid solution (H) having a solid content concentration of 20.0% by mass. It was. The number average molecular weight of this polyamic acid was 12,900, and the weight average molecular weight was 36,300.

<Synthesis Example 9>
A1 (3.22 g, 15.2 mmol), B5 (4.99 g, 10.1 mmol) and C5 (5.51 g, 40.5 mmol) were mixed in NMP (40.0 g) and reacted at 40 ° C. for 5 hours. After that, A4 (7.94 g, 35.4 mmol) and NMP (32.7 g) were added and reacted at 40 ° C. for a time to obtain a polyamic acid solution having a solid content concentration of 20.0 mass%.

After adding NMP to the obtained polyamic acid solution (15.0 g) and diluting to 6% by mass, acetic anhydride (2.15 g) and pyridine (1.11 g) were added as an imidization catalyst, and 1 at 40 ° C. The reaction was allowed for 5 hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (I). The imidation ratio of this polyimide was 50%, the number average molecular weight was 12,200, and the weight average molecular weight was 33,700.

<Synthesis Example 10>
A1 (2.98 g, 14.1 mmol), B3 (6.08 g, 14.1 mmol) and C4 (4.00 g, 32.8 mmol) were mixed in NMP (50.4 g) and reacted at 40 ° C. for 5 hours. After that, A5 (9.84 g, 32.8 mmol) and NMP (41.2 g) were added and reacted at 40 ° C. for 8 hours to obtain a polyamic acid solution having a solid content concentration of 20.0 mass%.

After adding NMP to the obtained polyamic acid solution (15.0 g) and diluting to 6% by mass, acetic anhydride (1.88 g) and pyridine (1.00 g) were added as imidization catalysts, Reacted for hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (J). The imidation ratio of this polyimide was 74%, the number average molecular weight was 11,500, and the weight average molecular weight was 35,600.

<Synthesis Example 11>
A1 (3.40 g, 16.0 mmol), C6 (3.62 g, 9.61 mmol), C1 (2.42 g, 22.4 mmol) were mixed in NMP (19.8 g) and reacted at 40 ° C. for 5 hours. After that, A2 (3.14 g, 16.0 mmol) and NMP (16.2 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution (K) having a solid content concentration of 20.0 mass%. It was. The number average molecular weight of this polyamic acid was 12,100, and the weight average molecular weight was 32,000.

<Synthesis Example 12>
A1 (3.30 g, 15.6 mmol), C6 (3.51 g, 9.33 mmol), C4 (2.66 g, 21.8 mmol) were mixed in NMP (19.8 g) and reacted at 40 ° C. for 5 hours. After that, A2 (3.05 g, 15.6 mmol) and NMP (16.2 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution having a solid content concentration of 20.0 mass%.

After adding NMP to the obtained polyamic acid solution (15.0 g) and diluting to 6% by mass, acetic anhydride (2.28 g) and pyridine (1.17 g) were added as imidization catalysts, Reacted for hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (L). The imidation ratio of this polyimide was 73%, the number average molecular weight was 12,000, and the weight average molecular weight was 29,100.

<Synthesis Example 13>
A2 (3.53 g, 18.0 mmol), B1 (2.05 g, 5.40 mmol) and C1 (1.36 g, 12.6 mmol) were mixed in NMP (30.1 g) and reacted at 40 ° C. for 8 hours. Thus, a polyamic acid solution having a solid content concentration of 20.0% by mass was obtained.

After adding NMP to the obtained polyamic acid solution (15.0 g) and diluting to 6% by mass, acetic anhydride (1.59 g) and pyridine (0.74 g) were added as an imidization catalyst, The reaction was allowed for 5 hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (M). The imidation ratio of this polyimide was 50%, the number average molecular weight was 14,700, and the weight average molecular weight was 40,100.

<Synthesis Example 14>
A3 (1.51 g, 6.05 mmol), B4 (2.70 g, 6.05 mmol) and C4 (1.73 g, 14.1 mmol) were mixed in NMP (19.2 g) and reacted at 80 ° C. for 5 hours. After that, A2 (2.77 g, 14.1 mmol) and NMP (19.2 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution having a solid content concentration of 20.0 mass%.

After adding NMP to the obtained polyamic acid solution (15.0 g) and diluting to 6% by mass, acetic anhydride (2.15 g) and pyridine (1.11 g) were added as imidization catalysts, The reaction was allowed for 5 hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (N). The imidation ratio of this polyimide was 53%, the number average molecular weight was 13,800, and the weight average molecular weight was 37,700.

<Synthesis Example 15>
A3 (3.43 g, 13.7 mmol), B3 (4.15 g, 9.60 mmol), C2 (1.93 g, 17.8 mmol) were mixed in NMP (26.8 g) and reacted at 80 ° C. for 5 hours. After that, A2 (2.69 g, 13.7 mmol) and NMP (22.0 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution having a solid content concentration of 20.0 mass%.

After adding NMP to the obtained polyamic acid solution (15.0 g) and diluting to 6% by mass, acetic anhydride (3.57 g) and pyridine (1.66 g) were added as imidization catalysts, Reacted for hours. This reaction solution was put into methanol (350 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (O). The imidation ratio of this polyimide was 52%, the number average molecular weight was 15,600, and the weight average molecular weight was 32,700.

<Example 1>
The polyamic acid solution (A) (9.03 g), NMP (8.91 g) and BCS (12.0 g) having a solid content concentration of 20.0% by mass obtained in Synthesis Example 1 were mixed at 25 ° C. for 6 hours. As a result, a liquid crystal aligning agent (1) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 2>
The polyimide powder (B) obtained in Synthesis Example 2 (1.80 g), NMP (2.72 g), NEP (9.03 g) and BCS (16.5 g) were mixed at 25 ° C. for 8 hours, A liquid crystal aligning agent (2) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 3>
The polyimide powder (C) obtained in Synthesis Example 3 (1.80 g), NEP (13.2 g), BCS (7.50 g) and PB (7.53 g) were mixed at 25 ° C. for 8 hours, A liquid crystal aligning agent (3) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 4>
The polyimide powder (D) (1.81 g), NMP (7.41 g), NEP (9.10 g), BCS (6.00 g) and PB (6.04 g) obtained in Synthesis Example 4 were heated to 25 ° C. For 8 hours to obtain a liquid crystal aligning agent (4). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 5>
The polyimide powder (E) obtained in Synthesis Example 5 (1.79 g), NMP (4.20 g), NEP (11.9 g) and PB (11.9 g) were mixed at 25 ° C. for 8 hours, A liquid crystal aligning agent (5) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 6>
The polyimide powder (F) obtained in Synthesis Example 6 (1.80 g), NEP (7.20 g), G-BL (9.06 g) and BCS (12.0 g) were mixed at 25 ° C. for 8 hours. Thus, a liquid crystal aligning agent (6) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 7>
Polyimide powder (G) (1.80 g), NEP (13.2 g), G-BL (6.02 g), BCS (6.01 g) and PB (3.00 g) obtained in Synthesis Example 7 By mixing at 8 ° C. for 8 hours, a liquid crystal aligning agent (7) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 8>
Polyamic acid solution (H) (9.00 g), G-BL (9.00 g), BCS (6.04 g) and PB (6.00 g) having a solid content concentration of 20.0% by mass obtained in Synthesis Example 8 Were mixed at 25 ° C. for 6 hours to obtain a liquid crystal aligning agent (8). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 9>
The polyimide powder (I) (1.80 g), NMP (14.7 g), and BCS (13.5 g) obtained in Synthesis Example 9 were mixed at 25 ° C. for 8 hours to obtain a liquid crystal aligning agent (9). Got. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 10>
The polyimide powder (J) (1.80 g), NMP (1.22 g), NEP (12.0 g), BCS (9.01 g) and PB (6.00 g) obtained in Synthesis Example 10 were heated to 25 ° C. For 8 hours to obtain a liquid crystal aligning agent (10). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 11>
Polyimide powder (B) obtained in Synthesis Example 2 (1.80 g), NMP (1.23 g), NEP (12.0 g), BCS (9.02 g), PB (6.03 g) and D1 (0.0. 05 g) was mixed at 25 ° C. for 8 hours to obtain a liquid crystal aligning agent (11). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 12>
The polyimide powder (C) (1.80 g), G-BL (19.2 g), BCS (9.01 g) and D2 (0.05 g) obtained in Synthesis Example 3 were mixed at 25 ° C. for 8 hours. Thus, a liquid crystal aligning agent (12) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 13>
Polyimide powder (C) obtained in Synthesis Example 3 (1.80 g), NMP (8.70 g), G-BL (9.00 g), BCS (9.01 g), PB (9.00 g) and D3 ( 0.05 g) was mixed at 25 ° C. for 8 hours to obtain a liquid crystal aligning agent (13). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 14>
Polyimide powder (B) obtained in Synthesis Example 2 (1.05 g), NMP (2.00 g), G-BL (9.02 g), BCS (9.02 g) and PB (9.02 g) The liquid crystal aligning agent (14) was obtained by mixing at 0 ° C. for 8 hours. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 15>
The polyimide powder (C) (1.06 g), NMP (5.01 g), NEP (9.10 g), BCS (7.60 g) and PB (7.60 g) obtained in Synthesis Example 3 were cooled to 25 ° C. For 8 hours to obtain a liquid crystal aligning agent (15). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Comparative Example 1>
The polyamic acid solution (K) (9.03 g), NMP (9.30 g) and BCS (12.2 g) having a solid content concentration of 19.9% by mass obtained in Synthesis Example 11 were mixed at 25 ° C. for 6 hours. Thus, a liquid crystal aligning agent (16) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Comparative example 2>
The polyimide powder (L) obtained in Synthesis Example 12 (1.80 g), NEP (13.2 g), BCS (7.52 g) and PB (7.50 g) were mixed at 25 ° C. for 8 hours, A liquid crystal aligning agent (17) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Comparative Example 3>
The polyimide powder (M) obtained in Synthesis Example 13 (1.80 g), NMP (2.71 g) NEP (9.00 g) and BCS (16.5 g) were mixed at 25 ° C. for 8 hours to obtain a liquid crystal. An alignment agent (18) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Comparative example 4>
The polyimide powder (N) (1.80 g), NEP (7.25 g), G-BL (9.06 g) and BCS (12.0 g) obtained in Synthesis Example 14 were mixed at 25 ° C. for 8 hours. Thus, a liquid crystal aligning agent (19) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Comparative Example 5>
The polyimide powder (O) (1.80 g), NMP (7.19 g), NEP (9.00 g), BCS (6.00 g) and PB (5.99 g) obtained in Synthesis Example 15 were heated to 25 ° C. For 8 hours to obtain a liquid crystal aligning agent (20). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

Using the liquid crystal aligning agents obtained in Examples 1 to 15 and Comparative Examples 1 to 5, “Preparation of liquid crystal cell (normal cell)”, “Evaluation of heat resistance of pretilt angle (normal cell)”, “Electrical properties (Evaluation of (voltage holding ratio) (normal cell) ”and“ Production of liquid crystal cell and evaluation of dispersibility of monomer (PSA cell) ” The conditions are as follows.

<Production of liquid crystal cell and evaluation of heat resistance of pretilt angle (vertical alignment) (normal cell)>
The liquid crystal alignment treatment agents obtained in Examples 1 to 15 and Comparative Examples 1 to 5 were spin-coated on the ITO surface of the substrate with 30 × 40 mm ITO electrode, and heat-cleaning clean at 80 ° C. for 5 minutes on a hot plate. A heat treatment was performed at 230 ° C. for 30 minutes in an oven to obtain a substrate with a liquid crystal alignment film (polyimide film) having a thickness of 100 nm.

The obtained polyimide film surface was rubbed with a rayon cloth using a rubbing apparatus having a roll diameter of 120 mm under the conditions of a roll rotation speed of 300 rpm, a roll traveling speed of 20 mm / sec, and an indentation amount of 0.2 mm, and a liquid crystal alignment film An attached substrate was obtained.

Two substrates with a liquid crystal alignment film after the rubbing treatment are prepared, the liquid crystal alignment film surface is inside, a 40 μm spacer is sandwiched, the rubbing directions are reversed, and the surroundings are bonded with a sealant. An empty cell was produced. Liquid crystal MLC-2003 (manufactured by Merck Japan Co., Ltd.) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain an antiparallel aligned nematic liquid crystal cell.

The pretilt angle of the liquid crystal cell produced above was measured. The liquid crystal cell was heated in a heat circulation oven at 120 ° C. for 24 hours, and then the pretilt angle was measured. The tilt measurement device (ELSICON model PAS-301) was used. The results are shown in Table 2.

<Production of liquid crystal cell and evaluation of electrical characteristics (normal cell)>
The liquid crystal alignment treatment agents obtained in Examples 1 to 5 and Comparative Examples 3 and 5 were spin-coated on the ITO surface of the substrate with 30 × 40 mm ITO electrode, and heat-cleaning clean at 80 ° C. for 5 minutes on a hot plate. The substrate was heat-treated at 230 ° C. for 30 minutes in an oven to obtain a substrate with a polyimide liquid crystal alignment film having a thickness of 100 nm.

Two substrates with the obtained liquid crystal alignment film were prepared, combined with a liquid crystal alignment film surface on the inside with a 6 μm spacer in between, and the periphery was adhered with a sealant to produce an empty cell. MLC-6608 (manufactured by Merck Japan) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain a nematic liquid crystal cell.

A voltage of 1 V is applied to the liquid crystal cell produced above at a temperature of 80 ° C. at 60 μm, the voltage after 16.67 ms and 50 ms is measured, and the voltage holding ratio (VHR) indicates how much the voltage can be maintained. As calculated. The measurement was performed using a VHR-1 voltage holding ratio measuring device (manufactured by Toyo Technica) with settings of Voltage: ± 1 V, Pulse Width: 60 μs, Frame Period: 16.67 ms or 50 ms. The liquid crystal cell for which the measurement of the voltage holding ratio was completed was irradiated with 50 J / cm ² of ultraviolet rays in terms of 365 nm, and then the voltage holding ratio was measured under the same conditions as described above. The ultraviolet irradiation was performed using a desktop UV curing device (HCT3B28HEX-1) (manufactured by SEN LIGHT CORPORATION). The results are shown in Table 3.

<Production of liquid crystal cell and evaluation of monomer dispersibility (PSA cell)>
The liquid crystal alignment treatment agents obtained in Examples 1 to 8, Examples 12 to 15 and Comparative Examples 1 to 5 were pressure filtered through a membrane filter having a pore diameter of 1 μm and stored at −15 ° C. for 48 hours. The monomer dispersibility was evaluated (PSA cell). This solution was washed with pure water and isopropyl alcohol (IPA) at the center with a 10 × 10 mm ITO electrode substrate with a pattern interval of 20 μm (length 40 mm × width 30 mm, thickness 0.7 mm) and 10 × 40 mm at the center. Spin coating on the ITO surface of the substrate with ITO electrode (length 40mm x width 30mm, thickness 0.7mm) and heat treatment at 100 ° C for 5 minutes on a hot plate to obtain a polyimide coating film with a film thickness of 100nm It was. After the coated surface was washed with pure water, it was heat-treated at 100 ° C. for 15 minutes in a heat circulation type clean oven to obtain a substrate with a liquid crystal alignment film.

A spacer of 4 μm is fixed on the liquid crystal alignment film surface of the substrate with the liquid crystal alignment film, and a nematic liquid crystal (MLC-6608) (manufactured by Merck Japan) has a polymerizable compound (also referred to as a monomer) represented by the following formula. ) (1) was added dropwise at 1 point to a liquid crystal prepared by mixing 0.7% by weight of the polymerizable compound (1) with respect to 100% by weight of the nematic liquid crystal (MLC-6608). Were bonded to obtain a liquid crystal cell for monomer dispersibility evaluation.

Since the resistance of the portion where the monomer present in the liquid crystal cell is present decreases, the dispersion region of the monomer in the liquid crystal cell is displayed in black by applying an AC voltage of 5 V to the obtained liquid crystal cell. The dispersibility of the monomer can be evaluated by measuring the size of a black display circle generated when a voltage is applied. Table 2 shows the measurement results of the diameters of the black display circles generated when the voltage is applied.

Further, for the liquid crystal alignment treatment agents obtained in Examples 9 to 11, evaluation of monomer dispersibility was performed in the same manner as above except that the polymerizable compound (2) was used instead of the polymerizable compound (1). Went.

<Evaluation of inkjet coating property of liquid crystal aligning agent>
The liquid crystal aligning agent (14) obtained in Example 14 of the present invention and the liquid crystal aligning agent (15) obtained in Example 15 were pressure filtered through a membrane filter having a pore size of 1 μm, and evaluation of ink jet coatability was performed. Went. As the ink jet coater, HIS-200 (manufactured by Hitachi Plant Technology) was used. Application is on an ITO (indium tin oxide) vapor-deposited substrate cleaned with pure water and IPA, the application area is 70 × 70 mm, the nozzle pitch is 0.423 mm, the scan pitch is 0.5 mm, and the application speed is 40 mm / Second, the time from application to temporary drying was 60 seconds, and temporary drying was performed on a hot plate at 70 ° C. for 5 minutes. As a result, in any of the examples, no repelling or pinholes were observed on the obtained liquid crystal alignment film, and a uniformly applied liquid crystal alignment film was obtained.

As can be seen from the above results, the liquid crystal alignment films obtained from the liquid crystal alignment treatment agents of Examples 1 to 15 were compared with the liquid crystal alignment films obtained from the liquid crystal alignment treatment agents of Comparative Examples 1 to 5. The monomer dispersion is wide. Therefore, it can be said that Examples 1 to 15 have high hydrophobicity and little alignment unevenness. In addition, comparing Example 3 and Comparative Example 2 which is the same as Example 3 except that C6 was used instead of B1, it can be said that Example 3 has a very wide dispersibility of the monomer. In the evaluation of the liquid crystal alignment properties, the liquid crystal alignment films obtained from the liquid crystal alignment treatment agents of Examples 1 to 15 were changed to the liquid crystal alignment films obtained from the liquid crystal alignment treatment agents of Comparative Examples 1 to 5. In comparison, the change in the pretilt angle before and after heating is small, and it can be said that the heat resistance of the pretilt angle is excellent.

In Comparative Examples 3 to 5 that do not contain the specific tetracarboxylic dianhydride, or in Comparative Examples 1 and 2 that do not contain the specific side chain diamine compound, the monomer spread is narrow and the heat resistance of the pretilt angle is also low. It was bad.

Also, as can be seen from Table 3, the liquid crystal cell obtained from the liquid crystal aligning agent of the example has a small decrease in voltage holding ratio even after being exposed to ultraviolet rays. Specifically, for example, except that Example 1 and A1 are not used, a comparison with Comparative Example 3 having the same configuration as Example 1 or A3 is used instead of Examples 4 and A1 This is a comparison with Comparative Example 5, which is the same as Example 4. Thus, by using the liquid-crystal aligning agent of this invention, it can be set as the liquid crystal display element which is excellent in the light holding resistance in voltage retention. This is because the liquid crystal aligning agent of the present invention contains a polymer (polyimide or polyimide precursor) using the tetracarboxylic dianhydride shown in [1] as a raw material, and thus firing when forming a liquid crystal alignment film. In the above, since the structure derived from the tetracarboxylic dianhydride represented by [1] crosslinks the polymer to cause imidization between the polymer molecules, the voltage holding ratio is excellent in light resistance. Guessed.

The liquid crystal alignment treatment agent of the present invention can provide a liquid crystal alignment film with improved alignment unevenness and excellent heat resistance at a pretilt angle. Therefore, the liquid crystal display element having the liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention has excellent reliability, and can be suitably used for a large-screen, high-definition liquid crystal television, etc. It is useful for a device, a TFT liquid crystal device, particularly a vertical alignment type liquid crystal display device.

Claims

A polyimide precursor obtained by reacting a tetracarboxylic acid component containing a tetracarboxylic dianhydride represented by the following formula [1] with a diamine component containing a diamine compound having a side chain represented by the following formula [2] The liquid crystal aligning agent characterized by including the body and at least 1 type of polymer chosen from the polyimide obtained by imidating this polyimide precursor.

(In formula [2], Y 1 represents a single bond, — (CH 2 ) a — (a is an integer of 1 to 15), —O—, —CH 2 O—, —COO— or —OCO—. Y 2 represents a single bond or — (CH 2 ) b — (b is an integer of 1 to 15), Y 3 is a single bond, — (CH 2 ) c — (c is an integer of 1 to 15) ), —O—, —CH 2 O—, —COO— or —OCO—, wherein Y 4 is a carbon having a divalent cyclic group selected from a benzene ring, a cyclohexane ring or a heterocyclic ring, or a steroid skeleton A divalent organic group having 17 to 51, wherein any hydrogen atom on the cyclic group contains an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, or fluorine having 1 to 3 carbon atoms May be substituted with an alkyl group, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom , Y 5 represents a divalent cyclic group selected from benzene ring, cyclohexane ring or a heterocyclic ring, any hydrogen atom on these cyclic groups, an alkyl group having 1 to 3 carbon atoms, having 1 to 3 carbon atoms May be substituted with an alkoxyl group, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom, n represents an integer of 0 to 4, and Y 6 represents a carbon number An alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 18 carbon atoms).
The liquid crystal aligning agent according to claim 1, wherein the tetracarboxylic acid component includes a tetracarboxylic acid anhydride represented by the following formula [3].

(In Formula [3], Z 1 is at least one tetravalent group selected from Formula [3a] to Formula [3j] below).

(In the formula [3a], Z 2 to Z 5 represent a hydrogen atom, a methyl group, a chlorine atom or a benzene ring, and may be the same or different. In the formula [3g], Z 6 and Z 7 are A hydrogen atom or a methyl group, which may be the same or different.
3. The liquid crystal aligning agent according to claim 1 or 2, which contains N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone as a solvent in the liquid crystal aligning agent. .
4. The solvent according to claim 1, further comprising a solvent selected from the solvents represented by the following formulas [D-1] to [D-3] as a solvent in the liquid crystal aligning agent. The liquid crystal aligning agent according to one item.

(In the formula [D-1], D 1 represents an alkyl group having 1 to 3 carbon atoms, and in the formula [D-2], D 2 represents an alkyl group having 1 to 3 carbon atoms, and the formula [D-3 ], D 3 represents an alkyl group having 1 to 4 carbon atoms).
A liquid crystal alignment film obtained by using the liquid crystal aligning agent according to claim 1.
A liquid crystal alignment film obtained by an ink jet method using the liquid crystal alignment treatment agent according to claim 1.
A liquid crystal display element comprising the liquid crystal alignment film according to claim 5.
A liquid crystal composition comprising a liquid crystal layer between a pair of substrates provided with electrodes and comprising a polymerizable compound that is polymerized by at least one of active energy rays and heat is disposed between the pair of substrates, and the electrodes 7. The liquid crystal alignment film according to claim 5, wherein the liquid crystal alignment film is used for a liquid crystal display device manufactured through a step of polymerizing the polymerizable compound while applying a voltage therebetween.
A liquid crystal display element comprising the liquid crystal alignment film according to claim 8.
A liquid crystal layer comprising a liquid crystal layer between a pair of substrates provided with electrodes, and a liquid crystal alignment film containing a polymerizable group that is polymerized by at least one of active energy rays and heat between the pair of substrates; 7. The liquid crystal alignment film according to claim 5, wherein the liquid crystal alignment film is used for a liquid crystal display device manufactured through a step of polymerizing the polymerizable group while applying a voltage therebetween.
A liquid crystal display element comprising the liquid crystal alignment film according to claim 10.
A polyimide precursor obtained by reacting a tetracarboxylic acid component containing a tetracarboxylic dianhydride represented by the following formula [1] with a diamine component containing a diamine compound having a side chain represented by the following formula [2] And a polymer comprising at least one selected from polyimides obtained by imidizing the polyimide precursor.

(In formula [2], Y 1 represents a single bond, — (CH 2 ) a — (a is an integer of 1 to 15), —O—, —CH 2 O—, —COO— or —OCO—. Y 2 represents a single bond or — (CH 2 ) b — (b is an integer of 1 to 15), Y 3 is a single bond, — (CH 2 ) c — (c is an integer of 1 to 15) ), —O—, —CH 2 O—, —COO— or —OCO—, wherein Y 4 is a carbon having a divalent cyclic group selected from a benzene ring, a cyclohexane ring or a heterocyclic ring, or a steroid skeleton A divalent organic group having 17 to 51, wherein any hydrogen atom on the cyclic group contains an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, or fluorine having 1 to 3 carbon atoms May be substituted with an alkyl group, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom , Y 5 represents a divalent cyclic group selected from benzene ring, cyclohexane ring or a heterocyclic ring, any hydrogen atom on these cyclic groups, an alkyl group having 1 to 3 carbon atoms, having 1 to 3 carbon atoms May be substituted with an alkoxyl group, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom, n represents an integer of 0 to 4, and Y 6 represents a carbon number An alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 18 carbon atoms).