KR102600209B1 - Polyimide precursor, and liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element having precursor - Google Patents

Abstract

The present invention provides a polyimide precursor with a relatively large amount of radical generation. A liquid crystal display element in which the reaction of a polymerizable compound is promoted by the polyimide precursor, the pretilt angle in the liquid crystal is efficiently set to a desired value, and the response speed is improved is provided. The present invention is a polyimide precursor using a first photo-radical-generating diamine, which is prepared under the same conditions as the polyimide precursor except that the first photo-radical-generating diamine is changed to a second photo-radical-generating diamine represented by formula (1). Provided is the polyimide precursor, which is characterized in that the amount of radicals generated upon light irradiation under the same conditions is greater than that of the formed second polyimide precursor.
[Formula 1]

Description

Polyimide precursor, and liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element having the precursor {POLYIMIDE PRECURSOR, AND LIQUID CRYSTAL ALIGNMENT AGENT, LIQUID CRYSTAL ALIGNMENT FILM, AND LIQUID CRYSTAL DISPLAY ELEMENT HAVING PRECURSOR}

The present invention provides a polyimide precursor with a relatively large amount of radical generation that can be used in a vertically aligned liquid crystal display element manufactured by irradiating ultraviolet rays while applying a voltage to the liquid crystal molecules, and a liquid crystal aligning agent having the polyimide precursor. , a liquid crystal aligning film formed with the liquid crystal aligning agent, and a liquid crystal display element formed with the liquid crystal aligning film.

A liquid crystal display element in which liquid crystal molecules aligned perpendicularly to the substrate are responded to by an electric field (also referred to as vertical alignment (VA) method) involves a process of irradiating ultraviolet rays while applying a voltage to the liquid crystal molecules during the manufacturing process. There is something that includes .

In such a vertically aligned liquid crystal display device, a photopolymerizable compound is added to the liquid crystal composition in advance, a vertical alignment film such as a polyimide type is used, and ultraviolet rays are irradiated while applying a voltage to the liquid crystal cell to change the response of the liquid crystal. Technology for increasing the speed (PSA (Polymer Sustained Alignment) type device, for example, see Patent Document 1 and Non-Patent Document 1) is known.

In such a PSA type device, the direction in which liquid crystal molecules in response to an electric field are usually tilted is controlled by protrusions formed on the substrate or slits formed in the display electrode, etc., but a photopolymerizable compound is added to the liquid crystal composition to form a liquid crystal cell. By irradiating ultraviolet rays while applying a voltage, a polymer structure that remembers the direction in which the liquid crystal molecules are tilted is formed on the liquid crystal alignment film, so the response of the liquid crystal display device is better than the method of controlling the tilt direction of the liquid crystal molecules with only protrusions or slits. It is said that the speed is increasing.

On the other hand, in this PSA type liquid crystal display device, there is a problem that the solubility of the polymerizable compound added to the liquid crystal is low and that it precipitates at low temperatures if the addition amount is increased. However, if the addition amount of the polymerizable compound is reduced, a good alignment state cannot be obtained. do. Additionally, unreacted polymerizable compounds remaining in the liquid crystal become impurities (contamination) in the liquid crystal, thereby reducing the reliability of the liquid crystal display element. In addition, if the UV irradiation treatment required for the PSA method is large, the components in the liquid crystal decompose, causing a decrease in reliability.

In addition, it has been reported that the response speed of a liquid crystal display element increases by adding a photopolymerizable compound not to the liquid crystal composition but to the liquid crystal alignment film (SC-PVA type liquid crystal display, see, for example, Non-Patent Document 2). .

Japanese Patent Publication No. 2003-307720

K. Hanaoka, SID 04 DIGEST, P.1200-1202 K.H Y.-J. Lee, SID 09 DIGEST, P.666-668

Recently, as the quality of liquid crystal display elements has improved, there has been a demand to further speed up the response speed of the liquid crystal to voltage application. To achieve this, it is necessary for the polymerizable compound to react efficiently with long-wavelength ultraviolet irradiation that does not decompose the components in the liquid crystal, thereby demonstrating the ability to fix the orientation. In addition, there is a need for no unreacted polymerizable compound to remain after ultraviolet irradiation, so as not to adversely affect the reliability of the liquid crystal display device.

The object of the present invention is to provide liquid crystal alignment that can improve the response speed of a liquid crystal display element obtained by using a process of reacting a polymerizable compound in a liquid crystal and/or a liquid crystal alignment film without accompanying the problems of the prior art described above. The object is to provide a liquid crystal alignment film and a liquid crystal display element.

More specifically, the object of the present invention is to provide a polyimide precursor with a relatively large amount of radical generation, to promote the reaction of the polymerizable compound by the polyimide precursor, and to efficiently adjust the pretilt angle in the liquid crystal to a desired value. The goal is to improve the response speed of the liquid crystal display device.

As a result of intensive study, the present inventors have introduced into a polyimide precursor a specific structure that generates radicals with respect to the polymer constituting the liquid crystal aligning agent by ultraviolet irradiation and has a relatively large amount of generation of the radicals, and the polyimide By using a liquid crystal aligning agent having a precursor, the above subject can be achieved by increasing the reactivity of the polymerizable compound in a liquid crystal display element obtained by using a process of reacting the polymerizable compound in the liquid crystal and/or the liquid crystal alignment film. By finding out what was possible, we completed the invention described in detail below.

<1> A polyimide precursor using a first photo-radical-generating diamine, formed under the same conditions as the polyimide precursor except that the first photo-radical-generating diamine is changed to a second photo-radical-generating diamine represented by formula (1). The polyimide precursor is characterized in that the amount of radicals generated upon light irradiation under the same conditions is greater than that of the second polyimide precursor.

[Formula 1]

<2> In <1> above, the wavelength of light at the time of light irradiation is preferably 300 nm to 400 nm.

<3> In the above <1> or <2>, it is preferable that the first photo radical-generating diamine is 0.1 to 100 mol% based on 100 mol% of the total diamine constituting the polyimide precursor.

<4> In the above <1> to <3>, the first photo-radical generating diamine is of formula (A)

(In the formula, Ar represents an aromatic hydrocarbon group that may have a substituent,

R ¹⁰¹ represents a divalent organic group,

R ¹⁰² to R ¹⁰⁴ each independently represent a monovalent organic group)

It is good to have a structure of

[Formula 2]

<5> In <4> above, -R ¹⁰¹ - a, -T ₁ -ST ₂ -

(During the ceremony,

T ₁ and T ₂ are each independently a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-,

S is a single bond, or an alkylene group with 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom (-CH ₂ - or -CF ₂ - in the alkylene group is -CH=CH-, or the following It may be substituted with a group selected from group G (however, groups selected from group G are not adjacent to each other) (group G: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring or a divalent heterocycle)))

It is better to express it as

<6> In <4> or <5> above, any one of R ¹⁰² to R ¹⁰⁴ is -OR ¹¹¹ (R ¹¹¹ is unsubstituted or substituted with a fluorine atom and has 1 to 20 carbon atoms. A straight chain or branched chain or cyclic alkyl group (-CH ₂ - or -CF ₂ - in the alkyl group is -CH=CH-, or a group selected from the following group G (however, the groups selected from the group G are mutually exclusive) (not adjacent to each other) may be substituted with (Group G: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, divalent carbon ring or divalent heterocycle)) It can be done) and,

The other two are each independently a linear or branched chain or cyclic alkyl group having 1 to 20 carbon atoms, -OR ¹¹² (R ¹¹² is selected from the group consisting of a straight-chain or branched-chain or cyclic alkyl group of 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom, and an aryl group of 6 to 20 carbon atoms that may have a substituent) group), a benzyl group, or a phenethyl group (if the other two are the alkyl group or -OR ¹¹² , they may be combined with each other to form a ring).

<7> In any one of the above <4> to <6>, Ar is preferably a phenylene group.

<8> In any one of the above <1> to <7>, the first photo-radical generating diamine has the following formula (2) (wherein Ar and R ¹⁰¹ to R ¹⁰⁴ have the same definitions as described above) ) is better expressed as .

[Formula 3]

<9> In any one of the above <1> to <8>, the first photo radical-generating diamine is preferably represented by the following formula (3).

[Formula 4]

<10> In any one of the above <1> to <9>, it is preferable that the polyimide precursor further has a side chain that vertically orients the liquid crystal.

<11> In any one of the above <1> to <10>, it is preferable that the polyimide precursor further has a side chain containing a photoreactive group in the structure.

<12> A polyimide obtained by imidizing the polyimide precursor of any one of the above <1> to <11>.

<13> A liquid crystal aligning agent having the polyimide precursor of any one of the above <1> to <11> and/or the polyimide of the above <12>.

<14> The method of <13> above contains a polymerizable compound in the liquid crystal and/or the liquid crystal alignment film, and is used in the production of a liquid crystal display element obtained by reacting the polymerizable compound by irradiating ultraviolet rays while applying a voltage. good night.

<15> A liquid crystal aligning film formed with the liquid crystal aligning agent of the above <13> or <14>.

<16> A liquid crystal display element provided with the liquid crystal alignment film of <15> above.

＜17＞ The following formula (A)

(In the formula, Ar represents an aromatic hydrocarbon group that may have a substituent,

R ¹⁰¹ represents a divalent organic group,

R ¹⁰² to R ¹⁰⁴ each independently represent a monovalent organic group)

Diamine having a structure represented by .

[Formula 5]

<18> In <17> above, -R ¹⁰¹ - is -T ₁ -ST ₂ - (wherein T ₁ and T ₂ are each independently a single bond, -O-, -COO-, -OCO- , -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-,

S is a single bond, or an alkylene group with 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom (-CH ₂ - or -CF ₂ - in the alkylene group is -CH=CH-, or the following It may be substituted with a group selected from group G (however, groups selected from group G are not adjacent to each other) (group G: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring or a divalent heterocycle)))

It is better to express it as

<19> In <17> or <18> above,

Any one of R ¹⁰² to R ¹⁰⁴ is -OR ¹¹¹ (R ¹¹¹ is a straight or branched chain or cyclic alkyl group of 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom (-CH ₂ - or -CF ₂ - in the alkyl group is -CH=CH -, or may be substituted with a group selected from the following group G (however, the groups selected from the group G are not adjacent to each other) (Group G: -O-, -COO-, -OCO-, -NHCO- , -CONH-, -NH-, a divalent carbon ring or a divalent heterocyclic ring))),

The other two are each independently a linear or branched chain or cyclic alkyl group having 1 to 20 carbon atoms, -OR ¹¹² (R ¹¹² is selected from the group consisting of a straight-chain or branched-chain or cyclic alkyl group of 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom, and an aryl group of 6 to 20 carbon atoms that may have a substituent) group), a benzyl group, or a phenethyl group (if the other two are the alkyl group or -OR ¹¹² , they may be combined with each other to form a ring).

<20> The diamine of any of the above <17> to <19> is preferably represented by the following formula (2) (Ar and R ¹⁰¹ to R ¹⁰⁴ have the same definitions as described above).

[Formula 6]

<21> The diamine of any one of <17> to <20> has the following formula (4) (R ¹⁰³ and R ¹⁰⁴ , and R ¹¹¹ have the same definitions as described above, and X ¹⁰¹ is a single bond or CO It is better to express .

[Formula 7]

<22> The diamine in any one of the above <17> to <21> is preferably selected from the group consisting of the following formulas (3) to (3)-12.

[Formula 8]

<23> The following formula (2) (wherein Ar represents an aromatic hydrocarbon group which may have a substituent, R ¹⁰¹ represents a divalent organic group, and R ¹⁰² to R ¹⁰⁴ each independently represent a monovalent organic group)

Diamine represented by .

[Formula 9]

<24> Diamine represented by the following formula (3).

[Formula 10]

<25> Diamine selected from the group consisting of the following formulas (3) to (3)-12.

[Formula 11]

<26> A polyimide precursor using the diamine of any one of <17> to <25> above.

<27> In the above <26>, the diamine of any one of the above <17> to <25> is preferably 0.1 to 100 mol%, based on 100 mol% of the total diamine constituting the polyimide precursor.

<28> In the polyimide precursor of <26> or <27> above, it is preferable to further have a side chain that vertically aligns the liquid crystal.

<29> In <28> above, the side chain that vertically orients the liquid crystal is represented by the following formula [II-1] (in formula [II-1], X ¹ is a single bond, -(CH ₂ ) _a - (a is an integer of 1 to 15), -O-, -CH ₂ O-, -COO- or OCO-. X ² is a single bond or (CH ₂ ) _b - (b is an integer of 1 to 15 X ³ represents a single bond, -(CH ₂ ) _c - (c is an integer from 1 to 15), -O-, -CH ₂ O-, -COO-, or OCO-. X ⁴ is represented by a benzene ring, cyclohexane ring, and a two -family ring -shaped group selected from the complex ring, and any hydrogen atom of these ring -type groups, alkoxyl groups of 1 to 3 carbon atoms, alkoxyl groups of 1 to 3 carbon atoms, carbon water It may be substituted with a fluorine-containing alkyl group of 1 to 3 carbon atoms, a fluorine-containing alkoxyl group of 1 to 3 carbon atoms, or a fluorine atom, and X ⁴ may be a divalent organic group selected from organic groups of 17 to 51 carbon atoms having a steroid skeleton. ^. It may be substituted with a fluorine-containing alkyl group of 1 to 3 carbon atoms, a fluorine-containing alkoxyl group of 1 to 3 carbon atoms, or a fluorine atom. ⁿ represents an integer of 0 to 4. It represents a fluorine-containing alkyl group, an alkoxyl group with 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group with 1 to 18 carbon atoms.)

and

[II-2]

_{( In} formula ^[ II-2] _, , -COO- or OCO-. X ⁸ represents an alkyl group with 8 to 22 carbon atoms or a fluorine-containing alkyl group with 6 to 18 carbon atoms.)

It is recommended that there is at least one selected from .

[Formula 12]

<30> The polyimide precursor according to any one of the above <26> to <29> preferably further has a side chain containing a photoreactive group in the structure.

<31> In <30> above, the side chain containing a photoreactive group in the structure is represented by the following formula [III]

(In formula [III], R ⁸ is a single bond, -CH ₂ -, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, - represents N(CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-. R ⁹ represents a single bond and an alkylene group having 1 to 20 carbon atoms which may be substituted with a fluorine atom; -CH ₂ - of the alkylene group may be optionally substituted with -CF ₂ - or -CH=CH-, and may be substituted with any of the following groups if they are not adjacent to each other: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring or heterocycle. R ¹⁰ represents a photoreactive group selected from the group consisting of the following formulas R ¹⁰ -1 to R ¹⁰ -7. )

or

Equation (IV)

(Y ₁ represents -CH ₂ -, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, or -CO-. Y ₂ represents alkyl having 1 to 30 carbon atoms. It is a lene group, a divalent carbon ring, or _a heterocyclic ring, and one or more hydrogen atoms of the alkylene group, a divalent carbon ring, or a heterocyclic ring may be substituted with a fluorine atom or an organic group. When not adjacent, -CH ₂ - may be substituted with these groups: -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-.Y ₃ represents -CH ₂ -, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, -CO-, or a single bond Y ₄ represents a cinnamoyl group Y ₅ is a single bond, an alkylene group having 1 to 30 carbon atoms, a divalent carbon ring, or a heterocyclic ring, and one or more hydrogen atoms of the alkylene group, a divalent carbon ring, or a heterocyclic ring are a fluorine atom or an organic group. Y ₅ may be substituted with -CH ₂ - if the following groups are not adjacent to each other: -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-. Y ₆ represents a photopolymerizable group that is an acrylic group or a methacryl group.)

It is better to express it as

[Formula 13]

<31> A polyimide obtained by imidizing the polyimide precursor of any one of the above <26> to <30>.

<32> A liquid crystal aligning agent having the polyimide precursor of any one of the above <26> to <31> and/or the polyimide of the above <31>.

<33> The method of <32> above contains a polymerizable compound in the liquid crystal and/or the liquid crystal alignment film, and is used in the production of a liquid crystal display element obtained by reacting the polymerizable compound by irradiating ultraviolet rays while applying a voltage. good night.

<34> A liquid crystal aligning film formed with the liquid crystal aligning agent of the above <32> or <33>.

<35> A liquid crystal display element provided with the liquid crystal alignment film of <34> above.

According to the present invention, a polyimide precursor with a relatively large amount of radical generation can be provided.

Moreover, by using the liquid crystal aligning agent which has this polyimide precursor and/or the liquid crystal aligning film formed with this liquid crystal aligning agent by this invention, even if the irradiation amount of ultraviolet rays is relatively low, the desired pretilt angle in a liquid crystal can be achieved. It is possible to obtain a vertically aligned liquid crystal display device with a fast response speed, especially a PSA type liquid crystal display device.

The present invention provides a polyimide precursor with a relatively large amount of radical generation, a diamine constituting the polyimide, a liquid crystal alignment agent having the polyimide precursor, a liquid crystal alignment film formed with the liquid crystal alignment agent, and a liquid crystal display element thereof. do. Afterwards, they will be explained in order.

＜Polyimide precursor with relatively high radical generation＞

The present invention provides a polyimide precursor with a relatively large amount of radical generation.

Specifically, the present invention provides a polyimide precursor using the first photo-radical generating diamine.

The polyimide precursor using the first photo-radical-generating diamine is different from the second polyimide precursor formed under the same conditions except that the first photo-radical-generating diamine is changed to the second photo-radical-generating diamine represented by formula (1). , is characterized by a large amount of radical generation upon light irradiation under the same conditions.

Here, the wavelength of light “at the time of light irradiation under the same conditions” is preferably 300 nm to 400 nm, preferably 310 to 380 nm, and more preferably 350 to 370 nm.

[Formula 14]

In addition, in this specification, "polyimide precursor" means what was obtained by reacting a diamine component and a tetracarboxylic dianhydride component.

In addition, in this specification, “polyimide precursor using ∼~ diamine” or “the polyimide precursor is formed using ∼∼ diamine” means that “∼∼ diamine” is used as a raw material for the polyimide precursor. do. Here, the “diamine” includes part or all of the raw materials.

In this specification, "--diamine constituting the polyimide precursor" means that "--diamine" is used as a raw material of the polyimide precursor, and the polyimide precursor is formed. Here, the “diamine” includes part or all of the raw materials.

The polyimide precursor of the present invention contains 0.1 to 100 mol%, preferably 10 to 80 mol%, and more preferably 30 to 100 mol% of the primary photo radical-generating diamine, based on 100 mol% of the total diamine constituting the polyimide precursor. It is better to have 50 mol%.

The first photo-radical generating diamine is given by formula (A)

(In the formula, Ar represents an aromatic hydrocarbon group that may have a substituent,

R ¹⁰¹ represents a divalent organic group,

R ¹⁰² to R ¹⁰⁴ each independently represent a monovalent organic group)

It is good to have a structure of

[Formula 15]

-R ¹⁰¹ - is preferably a group represented by -T ₁ -ST ₂ -.

Here, T ₁ and T ₂ are each independently a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ ) -, -CON(CH ₃ )-, or -N(CH ₃ )CO-,

S is a single bond, or an alkylene group with 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom (-CH ₂ - or -CF ₂ - in the alkylene group is -CH=CH-, or the following It may be substituted with a group selected from group G (however, groups selected from group G are not adjacent to each other) (group G: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring or a divalent heterocycle)).

Among R ¹⁰² to R ¹⁰⁴ , any one is -OR ¹¹¹ (R ¹¹¹ is a straight or branched chain or cyclic alkyl group of 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom (-CH ₂ - or -CF ₂ - in the alkyl group is -CH=CH -, or may be substituted with a group selected from the following group G (however, the groups selected from the group G are not adjacent to each other) (Group G: -O-, -COO-, -OCO-, -NHCO- , -CONH-, -NH-, a divalent carbon ring or a divalent heterocyclic ring))),

The other two are each independently a linear or branched chain or cyclic alkyl group having 1 to 20 carbon atoms, -OR ¹¹² (R ¹¹² is selected from the group consisting of a straight-chain or branched-chain or cyclic alkyl group of 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom, and an aryl group of 6 to 20 carbon atoms that may have a substituent) group), a benzyl group, or a phenethyl group (if the other two are the alkyl group or -OR ¹¹² , they may be combined with each other to form a ring).

Ar is preferably a group selected from phenylene, naphthylene, and biphenylene.

Ar, to which carbonyl is bonded, is involved in the absorption wavelength of ultraviolet rays, so when increasing the wavelength, a structure with a long conjugate length such as naphthylene or biphenylene is preferable. Ar may be substituted with a substituent, and such substituent is preferably an electron-donating organic group such as an alkyl group, hydroxyl group, alkoxy group, or amino group.

However, when Ar has a structure like naphthylene or biphenylene, the solubility deteriorates and the difficulty of synthesis also increases. Therefore, if the wavelength of ultraviolet rays is in the range of 300 nm to 400 nm, preferably 310 to 380 nm, sufficient characteristics can be obtained even with a phenyl group, so a phenyl group is most preferable.

The first photo-radical generating diamine is preferably represented by the following formula (2) (Ar and R ¹⁰¹ to R ¹⁰⁴ have the same definitions as described above). In addition, diaminobenzene may have a structure of any of o-phenylenediamine, m-phenylenediamine, or p-phenylenediamine, but in terms of reactivity with acid dianhydride, it is m-phenylenediamine, or p-phenylenediamine. -Phenylenediamine is preferred.

[Formula 16]

In particular, the first photo-radical generating diamine is a diamine represented by the following formula (4) (R ¹⁰³ and R ¹⁰⁴ and R ¹¹¹ have the same definitions as described above, and X ¹⁰¹ represents a single bond or CO) good night.

[Formula 17]

Specifically, the following formulas (3) to (3)-12 can be mentioned as the first photo-radical generating diamine, but it is not limited to these. It is preferable that the 1st photo-radical generating diamine is especially the diamine represented by Formula (3).

[Formula 18]

＜Side chains that orient the liquid crystal vertically＞

It is preferable that the polyimide precursor of the present invention further has a side chain that vertically orients the liquid crystal.

The side chain that vertically aligns the liquid crystal is represented by the following formula [II-1] or formula [II-2].

In formula [II-1], X ¹ to X ⁶ and n are as defined above. In addition, in the formula [II-2], X ⁷ and X ⁸ are as defined above.

[Formula 19]

Among them, X ¹ is a single bond, -(CH ₂ ) _a - (a is an integer of 1 to 15), -O-, -CH ₂ O-, or COO- is preferable, and more preferable is a single bond, -(CH ₂ ) _a - (a is an integer of 1 to 10), -O-, -CH ₂ O-, or COO-. Among them, X ² is preferably a single bond or (CH ₂ ) _b - (b is an integer of 1 to 10). X ³ is, among others, preferably a single bond, -(CH ₂ ) _c - (c is an integer of 1 to 15), -O-, -CH ₂ O- or COO- in terms of ease of synthesis, and more Preferred are single bonds, -(CH ₂ ) _c - (c is an integer of 1 to 10), -O-, -CH ₂ O- or COO-.

Among them, X ⁴ is preferably an organic group of 17 to 51 carbon atoms having a benzene ring, a cyclohexane ring, or a steroid skeleton from the viewpoint of ease of synthesis. X ⁵ is, among others, preferably a benzene ring or a cyclohexane ring. Among these, n is preferably 0 to 3, and more preferably 0 to 2, from the viewpoint of availability of raw materials and ease of synthesis.

Among these, X ⁶ is preferably an alkyl group with 1 to 18 carbon atoms, a fluorine-containing alkyl group with 1 to 10 carbon atoms, an alkoxyl group with 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group with 1 to 10 carbon atoms. More preferably, it is an alkyl group with 1 to 12 carbon atoms or an alkoxyl group with 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 X ¹ , X ² , ^{X 3} , X ⁴ , X ⁵ , The same combinations as (2-1) to (2-629) shown in Tables 6 to 47 on page 34 can be used. In addition, in each table of the international publication, X ¹ to X ⁶ in the present invention are shown as Y1 to Y6, but Y1 to ^Y6 are read as X ¹ to

In addition, in (2-605) to (2-629) published in each table of the International Publication Publication, the organic group having 17 to 51 carbon atoms having a steroid skeleton in the present invention is a group having 12 to 25 carbon atoms having a steroid skeleton. Although shown as an organic group, 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. Among them, (2-25) to (2-96), (2-145) to (2-168), (2-217) to (2-240), (2-268) to (2-315) , (2-364) to (2-387), (2-436) to (2-483) or (2-603) to (2-615) is preferable. Particularly preferred combinations are (2-49) to (2-96), (2-145) to (2-168), (2-217) to (2-240), (2-603) to (2- 606), (2-607) to (2-609), (2-611), (2-612) or (2-624).

In formula [II-2], especially, X ⁷ is preferably a single bond, -O-, -CH ₂ O-, -CONH-, -CON(CH ₃ )- or COO-, more preferably , a single bond, -O-, -CONH- or COO-. X ⁸ is especially preferably an alkyl group having 8 to 18 carbon atoms.

As the side chain that vertically aligns the liquid crystal, it is preferable to use the structure represented by the formula [II-1] because it can increase the orientation of the liquid crystal and stabilize it.

In addition, the ability of a polyimide precursor having a side chain to vertically orient the liquid crystal varies depending on the structure of the side chain to vertically orient the liquid crystal, but generally, the side chain to vertically orient the liquid crystal As the amount increases, the ability to vertically align the liquid crystal increases, and as it decreases, it decreases. Additionally, when it has a cyclic structure, the ability to vertically align the liquid crystal tends to be higher compared to when it does not have a cyclic structure.

＜Photoreactive side chain＞

The polyimide precursor of the present invention may have a photoreactive side chain. The photoreactive side chain has a functional group (also referred to as a photoreactive group in this specification) that can react with irradiation of light such as ultraviolet rays (UV) to form a covalent bond. That is, the polyimide precursor of the present invention preferably further has a side chain containing a photoreactive group in its structure.

The photoreactive side chain may be directly bonded to the main chain of the polymer, or may be bonded through a linking group. The photoreactive side chain is represented by the following formula [III], for example.

[Formula 20]

In formula [III], R ⁸ , R ⁹ , and R ¹⁰ are as defined above. Among them, R ⁸ is preferably a single bond, -O-, -COO-, -NHCO, or -CONH-. R ⁹ can be formed by conventional organic synthesis methods, but from the viewpoint of ease of synthesis, a single bond or an alkylene group having 1 to 12 carbon atoms is preferable.

In addition, the divalent carbon ring or heterocycle that substitutes any -CH ₂ - of R ⁹ is specifically exemplified by the following.

[Formula 21]

R ¹⁰ is preferably a methacryl group, an acrylic group, or a vinyl group from the viewpoint of photoreactivity.

The amount of the photoreactive side chain is preferably in a range that can speed up the response speed of the liquid crystal by reacting with irradiation of ultraviolet rays to form a covalent bond. In order to speed up the response speed of the liquid crystal, other characteristics It is desirable to have as much as possible without affecting it.

<Polyimide precursor forming liquid crystal aligning agent>

The method of producing a polyimide precursor using the first photo-radical generating diamine and a polyimide obtained by imidizing the polyimide precursor is not particularly limited. For example, a method of polymerizing the first photo-radical generating diamine and tetracarboxylic dianhydride, a method of polymerizing the first photo radical-generating diamine and other diamines and tetracarboxylic dianhydride, etc. are mentioned.

The same method as described above can be used for producing a polyimide precursor further having a side chain for vertically aligning the liquid crystal and/or a photoreactive side chain, and a polyimide obtained by imidizing the polyimide precursor. The preferred method also involves polymerizing a first photo-radical-generating diamine containing a side chain that vertically aligns the liquid crystal and/or a first photo-radical-generating diamine containing a photo-reactive side chain, and tetracarboxylic dianhydride. It is preferable to do so.

<Synthesis of the first photo-radical generating diamine>

In the present invention, the first photo-radical generating diamine is synthesized through each step to form a dinitro form, a mononitro form or a diamine having an amino group with a removable protecting group in the reduction step, and convert it into nitro form by a commonly used reduction reaction. It can be obtained by converting the group to an amino group or deprotecting the protecting group.

The method for synthesizing the first photo-radical generating diamine of the present invention is not particularly limited, but for example, the following formula (5) (In formula (5), Ar, R ¹⁰¹ to R ¹⁰⁴ are represented by the formula (A) A method of synthesizing a dinitro compound represented by (same as each definition in) and further reducing the nitro group and converting it to an amino group can be cited.

[Formula 22]

There is no particular limitation on the method for reducing the nitro group, but for example, palladium-carbon, platinum oxide, Raney nickel, platinum-carbon, rhodium-alumina, platinum sulfide carbon, reduced iron, iron chloride, tin, tin chloride, zinc, etc. are used as catalysts. There are methods using hydrogen gas, hydrazine, hydrogen chloride, ammonium chloride, etc.

If the structure has an unsaturated bond site, a reduction method that does not reduce the unsaturated bond can be used.

There is no particular limitation on the reduction method as long as the unsaturated bond is not reduced. For example, reduced iron, tin, tin chloride, poisoned palladium-carbon, and poisoned platinum-carbon are used as catalysts, and hydrogen gas, hydrazine, and hydrogen chloride are used as catalysts. , ammonium chloride, etc.

If the structure has a benzyl binding site, a reduction method that does not cleave the benzyl group can be used.

There are no restrictions on the reduction method as long as the benzyl group is not cleaved. For example, platinum black, rhodium-alumina, platinum carbon sulfide, reduced iron, iron chloride, tin, tin chloride, zinc, etc. are used as catalysts, hydrogen gas, hydrazine, There are methods using hydrogen chloride, ammonium chloride, etc.

As the reaction solvent, a solvent that does not affect the reaction can be used. For example, ester solvents such as ethyl acetate and methyl acetate, aromatic hydrocarbon solvents such as toluene and xylene, aliphatic hydrocarbon solvents such as n-hexane, n-heptane, and cyclohexane, 1,2-dimethoxyethane, and tetrahydrocarbon solvents. Ether-based solvents such as hydrofuran and dioxane, alcohol-based solvents such as methanol and ethanol, ketone-based solvents such as 2-butanone and 4-methyl-2-pentanone, N,N-dimethylformamide, N,N -Aprotic polar solvents such as dimethylacetamide, N-methyl-2-pyrrolidone, and dimethyl sulfoxide, and water. These organic solvents can be used individually or in combination of two or more types.

The reaction temperature can be carried out at a temperature at which the reaction proceeds efficiently as long as the raw materials or products do not decompose and is below the boiling point of the solvent used. Specifically, a temperature of -78°C to less than the boiling point of the solvent is preferable, and a temperature of 0°C to less than the boiling point of the solvent is more preferable from the viewpoint of simplicity of synthesis.

There are no particular restrictions on the method for synthesizing the compound of formula (5), but for example, R ¹⁰² in formula (5) is OR ¹¹¹ (R ¹¹¹ is the same as the definition described in <6> above), the following formula (6) (In formula (6), Ar, R ¹⁰¹ , R ¹⁰³ , and R ¹⁰⁴ are each in the formula (A) A method of synthesizing the dinitro compound represented by (same as the definition of) and further introducing a substituent to the OH group can be mentioned.

[Formula 23]

There is no particular limitation on the method of introducing a substituent to the OH group, but for example, the formula (7) below (L ¹ in formula (7) is halogen, an alkanesulfonyloxy group, or an arenesulfonyloxy group, and R ¹¹¹ is the < above. A method of reacting an alkyl halide or an alkyl sulfonic acid ester represented by (same as the definition described in 6>) under neutral conditions or alkaline conditions is included.

[Formula 24]

The reaction solvent and reaction temperature are as described above, but alcohol solvents and water are not preferred because they may react with the raw materials.

Alkyl halides include methyl iodide, ethyl iodide, n-propyl iodide, n-butyl iodide, n-octadecyl iodide, benzyl iodide, bromoethane, 1-bromopropane, 1-bromobutane, and 1-bromo. Octadecane, benzyl bromide, chloroethane, 1-chloropropane, 1-chlorobutane, 1-chlorooctadecane, benzyl chloride, methyl methanesulfonate, ethyl methanesulfonate, n-propyl methanesulfonate, n-butyl methanesulfonate, methanesulfonate n-octadecyl, benzyl methanesulfonate, etc. are mentioned.

When the compound represented by formula (5) is represented by the formula (8) below, the compound represented by the formula (6) and the vinyl ether represented by the formula (9) are reacted without a catalyst or under an acid catalyst. Synthesis methods include:

Additionally, in formula (8), Ar, R ¹⁰¹ , R ¹⁰³ , and R ¹⁰⁴ are the same as each definition in formula (A) above, and R ²¹¹ is the number of carbon atoms that are unsubstituted or substituted with a fluorine atom. 1 to 18 straight or branched chain or cyclic alkyl group (-CH ₂ - or -CF ₂ - in the alkyl group is -CH=CH-, or a group selected from the following group G (however, in the group G The selected groups are not adjacent to each other) and may be substituted (Group G: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, divalent carbon ring or divalent heterocycle ) may be replaced with ).

In addition, R ²¹¹ in formula (9) is the same as the definition of R ²¹¹ in formula (8) above.

[Formula 25]

Examples of vinyl ether include ethyl vinyl ether, n-butyl vinyl ether, n-octadecyl vinyl ether, and diethylene glycol monovinyl ether.

Examples of the acid catalyst include p-toluenesulfonic acid, pyridinium p-toluenesulfonate, and methanesulfonic acid.

When the compound represented by formula (5) is represented by the following formula (10) (in formula (10), Ar, R ¹⁰¹ , R ¹⁰³ , and R ¹⁰⁴ are the same as each definition in formula (A) above) Examples include a synthesis method in which the compound represented by the above formula (6) and 3,4-dihydropyran are reacted without a catalyst or under an acid catalyst.

[Formula 26]

When the compound represented by formula (5) is represented by the following formula (11) (in formula (11), Ar, R ¹⁰² to R ¹⁰⁴ are the same as each definition in formula (A), and S and T ₂ is the same as the definition described in <5> above), a dinitro compound represented by the following formula (12) (in formula (12), L ² is halogen), and formula (13) (formula (13) Among them, Ar, R ¹⁰² to R ¹⁰⁴ are the same as the respective definitions in the above formula (A), and S and T ₂ are the same as the definitions described in <5> above.) The alcohol represented by the reaction is reacted in the presence of an alkali. How to do it, etc. The reaction solvent and reaction temperature are as described above, but protic solvents such as alcohol-based solvents and water can be used as long as they do not react with the raw materials.

[Formula 27]

Compounds represented by formula (12) include 2,4-dinitrofluorobenzene, 2,4-dinitrochlorobenzene, 2,4-dinitrobromobenzene, 2,4-dinitroiodobenzene, 3, Examples include 5-dinitrochlorobenzene, 3,5-dinitroiodobenzene, 3,4-dinitrofluorobenzene, 3,4-dinitrochlorobenzene, and 2,3-dinitrochlorobenzene.

There are no particular restrictions on the method for synthesizing the compound represented by formula (13), but for example, R ¹⁰² in formula (13) When is represented by OR ¹¹¹ , the following formula (14) (in formula (14), Ar, R ¹⁰³ and R ¹⁰⁴ are the same as each definition in formula (A) above, and S and T ₂ are the above (same as the definition described in <5>), the primary hydroxyl group of the compound represented by is protected by a protecting group, a substituent is introduced into the remaining tertiary hydroxyl group, and then the protecting group of the primary hydroxyl group is deprotected.

[Formula 28]

Compounds represented by formula (14) include 2-hydroxy-1-(4-(hydroxymethyl)phenyl)-2-methyl-1-propanone, 1-hydroxycyclohexyl (4-(2-hydr) Roxyethyl)phenyl))ketone, 1-hydroxycyclohexyl(4-hydroxyphenyl)ketone, 2-hydroxy-1-(4-((2-hydroxyethyl)thio)phenyl)-2-methyl- 1-Propanone, 2-hydroxy-1-(4-hydroxyphenyl)-2-methyl-1-propanone, 2-hydroxy-1-(4-(2-hydroxyethoxy)phenyl)- 2-methyl-1-propanone, 1-(3,4-dihydroxyphenyl)-2-hydroxy-2-methyl-1-propanone, 2-hydroxy-1-(4-(2-hydroxy Examples include oxyethyl)phenyl)-2-methyl-1-propanone and 2-hydroxy-1-(4-(3-hydroxypropyl)phenyl)-2-methyl-1-propanone.

There is no particular limitation on the protecting group, but examples include tetrahydropyranyl group, benzyl group, p-methoxybenzyl group, methoxymethyl group, trimethylsilyl group, t-butyldimethylsilyl group, acetyl group, benzoyl group, and trityl group. etc. can be mentioned.

There is no particular limitation on the method of introducing a tertiary hydroxyl group after protecting the primary hydroxyl group of the compound represented by formula (14), for example, R ¹⁰² in formula (5) is OR ¹¹¹ In this case, the same conditions as in the case of synthesizing the compound represented by formula (5) from the compound represented by formula (6) can be used.

There is no particular limitation on the deprotection method for each protecting group, and general deprotection reaction conditions can be applied.

The compound represented by formula (5) has the following formula (15) (in formula (15), Ar, R ¹⁰² to R ¹⁰⁴ are the same as the respective definitions in formula (A), and S and T ₂ are (same as the definition described in <5>), a dinitro compound represented by the following formula (16) (in formula (16), L ¹ has the same definition as L ¹ in formula (7)) , a method of reacting the alcohol represented by formula (13) in the presence of an alkali, etc. The reaction solvent and reaction temperature are as described above, but protic solvents such as alcohol-based solvents and water can be used as long as they do not react with the raw materials.

[Formula 29]

Compounds represented by formula (16) include 3,5-dinitrobenzyl chloride, methanesulfonic acid (3,5-dinitrobenzyl), 2,4-dinitrobenzyl chloride, and methanesulfonic acid (2,4-dinitrobenzyl). ), etc.

When the compound represented by formula (5) is represented by the following formula (17) (in formula (17), Ar, R ¹⁰² to R ¹⁰⁴ , S, T ₂ are the same as the definitions described in <5> above) In this, a dinitro compound represented by the following formula (18) (L ² in formula (18) has the same definition as L ² in formula (12)) and an alcohol represented by formula (13) are reacted in the presence of an alkali. or a method of reacting the dinitro compound represented by formula (19) with the alcohol represented by formula (13) in the presence of a dehydration condensation agent. The reaction solvent and reaction temperature are as described above, but protic solvents such as alcohol-based solvents and water can be used as long as they do not react with the raw materials.

[Formula 30]

Examples of the compound represented by formula (18) include 3,5-dinitrobenzoyl chloride.

Examples of the compound represented by formula (19) include 3,5-dinitrobenzoic acid.

Dehydration condensation agents include dicyclohexylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, diisopropylcarbodiimide, 1,1'-carbonyldiimidazole, and bis( 2-oxo-3-oxazolinidyl)phosphinic acid chloride, di-2-pyridyl carbonate, triphenyl phosphite, dimethoxy-1,3,5-triazinylmethylmorpholinium, O-(benzotriazole- 1-yl)-N,N,N',N'-tetramethyluroniumtetrafluoroborate, O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium Hexafluorophosphate, (2,3-dihydro-2-thioxo-3-benzooxazolyl)diphenyl phosphonate, etc. are mentioned.

<Polyimide precursor having a side chain that vertically orients the liquid crystal>

In the method of introducing a side chain that vertically aligns the liquid crystal into a polyimide precursor, it is preferable to use a diamine having a specific side chain structure as part of the diamine component. In particular, it is preferable to use the diamine (also referred to as a specific side chain type diamine compound) represented by the following formula [2].

[Formula 31]

In formula [2],

As the specific side chain type diamine, it is preferable to use the diamine represented by the following formula [2-1] from the point that high and stable vertical alignment of the liquid crystal can be obtained.

[Formula 32]

X ¹ , X ^{2 ,} X ³ , X ⁴ , Preferred ones are the same as those defined in each of the above formulas [II-1].

In addition, in formula [2-1], m is an integer of 1 to 4. Preferably it is an integer of 1.

Specific side chain type diamine specifically includes structures represented by the following formula [2a-1] to formula [2a-31].

In addition, in the formula, R ¹ represents -O-, -OCH ₂ -, -CH ₂ O-, -COOCH ₂ -, or CH ₂ OCO-, and R ² is a straight-chain or branched alkyl group having 1 to 22 carbon atoms, A linear or branched alkoxyl group having 1 to 22 carbon atoms, a linear or branched fluorine-containing alkyl group or a fluorine-containing alkoxyl group having 1 to 22 carbon atoms.

R ³ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O-, -OCH ₂ - or CH ₂ -, and R ⁴ is a linear or branched alkyl group having 1 to 22 carbon atoms, a linear or branched alkoxyl group having 1 to 22 carbon atoms, a linear or branched fluorine-containing alkyl group or a fluorine-containing alkoxyl group having 1 to 22 carbon atoms. .

R ⁵ is -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O-, -OCH ₂ -, -CH ₂ -, -O- or NH-, and R ⁶ is a fluorine group, cyano group, trifluoromethane group, nitro group, azo group, formyl group, acetyl group, acetoxy group, or hydroxyl group.

R ⁷ is a straight-chain or branched alkyl group having 3 to 12 carbon atoms, and the cis-trans isomer of 1,4-cyclohexylene is each trans isomer.

R ⁸ is a linear or branched alkyl group having 3 to 12 carbon atoms, and the cis-trans isomer of 1,4-cyclohexylene is each trans isomer.

A ₄ is a straight-chain or branched alkyl group having 3 to 20 carbon atoms which may be substituted with a fluorine atom, A ₃ is a 1,4-cyclohexylene group or 1,4-phenylene group, and A ₂ is an oxygen atom or COO -* (however, the bond with “*” is bonded to A ₃ ), and A ₁ is an oxygen atom or COO-* (however, the bond with “*” is bonded with (CH ₂ )a ₂ ) It is). Moreover, a ₁ is an integer of 0 or 1, a ₂ is an integer of 2 to 10, and a ₃ is an integer of 0 or 1.

[Formula 33]

[Formula 34]

[Formula 35]

Among the above formulas [2a-1] to [2a-31], particularly preferred ones are formula [2a-1] to formula [2a-6], formula [2a-9] to formula [2a-13] or formula [2a- 22] ~ Formula [2a-31].

Moreover, as diamine which has a specific side chain structure represented by formula [II-2], diamine represented by the following formula [2b-1] - [2b-10] is mentioned.

A ¹ represents an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group.

[Formula 36]

In the above formulas [2b-5] to [2b-10], A ¹ is -COO-, -OCO-, -CONH-, -NHCO-, -CH ₂ -, -O-, -CO-, or NH- , and 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.

The said diamine can also be used 1 type or in mixture of 2 or more types depending on characteristics, such as liquid crystal orientation when used as a liquid crystal alignment film, a pretilt angle, a voltage maintenance characteristic, and an accumulated charge.

The diamine having a side chain that vertically aligns the liquid crystal is preferably used in an amount of 5 to 50 mol% of the diamine component used in the synthesis of polyamic acid, more preferably in an amount of 10 to 40 mol% of the diamine component, especially Preferably it is 15 to 30 mol%.

The use of a diamine having a side chain that vertically aligns the liquid crystal is particularly excellent in terms of improvement in response speed and the ability to fix the orientation of the liquid crystal.

<Diamine containing photoreactive side chains>

Examples of the diamine having a photoreactive side chain include diamine having a side chain represented by formula [3], and specifically, the following general formula [3] (R ⁸ , R ⁹ and R ¹⁰ in formula [3] The definition of is the same as the above formula [III]), but is not limited to this.

[Formula 37]

The bonding position of two amino groups (-NH ₂ ) in formula [3] is not limited. Specifically, with respect to the linking group in the side chain, the positions 2,3, 2,4, 2,5, 2,6, 3,4, and 3,5 on the benzene ring. I can hear it. Among them, the 2,4 position, 2,5 position, or 3,5 position is preferable from the viewpoint of reactivity when synthesizing polyamic acid. Considering the ease of synthesizing diamine, the 2,4 position or the 3,5 position is more preferable.

Diamines having photoreactive side chains specifically include the following.

In the formula, X ^{9 and} It represents energy.

[Formula 38]

Moreover, the diamine which has a photoreactive side chain also includes the diamine which has in the side chain the group which causes a photo dimerization reaction shown by the following formula, and the group which causes a photopolymerization reaction.

[Formula 39]

In the above formula, Y ₁ represents -CH ₂ -, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, or -CO-. Y ₂ is an alkylene group having 1 to 30 carbon atoms, a divalent carbon ring, or a heterocycle, and one or more hydrogen atoms of the alkylene group, a divalent carbon ring, or a heterocycle may be substituted with a fluorine atom or an organic group. do. In Y ₂ , -CH ₂ - may be substituted with the following groups if they are not adjacent to each other; -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-. Y ₃ represents -CH ₂ -, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, -CO-, or a single bond. Y ₄ represents Cinnamo Diary. Y ₅ is a single bond, an alkylene group having 1 to 30 carbon atoms, a divalent carbon ring, or a heterocyclic ring, and one or more hydrogen atoms of the alkylene group, a divalent carbon ring, or heterocycle are substituted with a fluorine atom or an organic group. It can be done. Y ₅ may have -CH ₂ - substituted with the following groups if they are not adjacent to each other; -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-. Y ₆ represents a photopolymerizable group that is an acrylic group or a methacryl group.

The diamine having the photoreactive side chain is one type depending on the characteristics such as liquid crystal orientation when used as a liquid crystal alignment film, pretilt angle, voltage holding characteristics, and accumulated charge, and the response speed of the liquid crystal when used as a liquid crystal display element. Alternatively, two or more types can be mixed and used.

Moreover, as for the diamine which has a photoreactive side chain, it is preferable to use 10-70 mol% of the diamine component used for synthesis of a polyamic acid, More preferably, it is 20-60 mol%, Especially preferably, it is 30-70 mol%. It is 50 mol%.

＜Other diamines＞

In addition, when producing a polyimide precursor and/or polyimide, diamines other than the above-mentioned diamines can be used together as a diamine component, as long as they do not impair the effect of the present invention. Specifically, for example, p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2, 4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 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'-biphenyl, 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, 4,4'-diaminodiphenylmethane Phenyl 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'-diaminodiphenyl)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, 2,6diaminonaphthalene, 2,7-diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis(4-aminophenyl)ethane, 1,2-bis(3- Aminophenyl) ethane, 1,3-bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, 1,4-bis (4-aminophenyl) butane, 1,4-bis ( 3-aminophenyl)butane, 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, 1,3-bis (4-aminophenoxy) Si) Benzene, 4,4'-[1,4-phenylenebis(methylene)]dianiline, 4,4'-[1,3-phenylenebis(methylene)]dianiline, 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), 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)hexafluoro Propane, 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, 3,5-diaminobenzoic acid, 2,5-diaminobenzoic acid, 1,3-bis(4-aminophenoxy)propane, 1, 3-bis(3-aminophenoxy)propane, 1,4-bis(4-aminophenoxy)butane, 1,4-bis(3-aminophenoxy)butane, 1,5-bis(4-aminophenoxy) Si) 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-(4-aminophenoxy)decane, 1,10-(3-amino) Phenoxy)decane, 1,11-(4-aminophenoxy)undecane, 1,11-(3-aminophenoxy)undecane, 1,12-(4-aminophenoxy)dodecane, 1,12 -Aromatic diamines such as (3-aminophenoxy)dodecane, alicyclic diamines such as bis(4-aminocyclohexyl)methane and bis(4-amino-3-methylcyclohexyl)methane, and 1,3-diamino. Propane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminoctane, 1,9-diaminononane and aliphatic diamines such as 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminodecane.

The above-mentioned other diamines can also be used one type or in mixture of two or more types depending on characteristics such as liquid crystal orientation when used as a liquid crystal alignment film, pretilt angle, voltage holding characteristic, and accumulated charge.

＜Tetracarboxylic dianhydride＞

The tetracarboxylic dianhydride component reacted with the diamine component is not particularly limited. Specifically, 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)propane, bis(3,4-dicarboxyphenyl)dimethylsilane, bis(3,4-dicarboxyphenyl)diphenylsilane, 2,3,4,5-pyridinetetracar Boxylic acid, 2,6-bis(3,4-dicarboxyphenyl)pyridine, 3,3',4,4'-diphenylsulfonetetracarboxylic acid, 3,4,9,10-perylenetetracarboxyl Acid, 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic acid, oxydiphthalatetetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2 ,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid Boxylic acid, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3 ,4-cycloheptanetetracarboxylic acid, 2,3,4,5-tetrahydrofurantetracarboxylic acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid , 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid, bicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic acid, bicyclo [4,3,0]nonane-2,4,7,9-tetracarboxylic acid, bicyclo[4,4,0]decane-2,4,7,9-tetracarboxylic acid, bicyclo[4 ,4,0]decane-2,4,8,10-tetracarboxylic acid, tricyclo[6.3.0.0<2,6>]undecane-3,5,9,11-tetracarboxylic acid, 1, 2,3,4-Butanetetracarboxylic acid, 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid , bicyclo[2,2,2]oct-7-en-2,3,5,6-tetracarboxylic acid, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclo Hexane-1,2-dicarboxylic acid, tetracyclo[6,2,1,1,0,2,7]dodeca-4,5,9,10-tetracarboxylic acid, 3,5,6- Tricarboxynorbornane-2:3, 5:6 dicarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, etc. are mentioned. Of course, tetracarboxylic dianhydride may also be used one type or in combination of two or more types depending on characteristics such as liquid crystal orientation when used as a liquid crystal alignment film, voltage holding characteristics, and accumulated charge.

＜Polymerizable compound＞

The liquid crystal aligning agent of this invention may contain the polymeric compound which has the group photopolymerized or photocrosslinked at two or more terminals as needed. These polymerizable compounds are compounds having two or more terminals having groups that are photopolymerized or photocrosslinked. Here, a polymerizable compound having a group that undergoes photopolymerization is a compound that has a functional group that undergoes polymerization by irradiating light. In addition, the compound having a photo-crosslinking group means that by irradiating light, it reacts with at least one polymer selected from the group consisting of a polymer of a polymerizable compound, a polyimide precursor, and a polyimide obtained by imidizing this polyimide precursor, thereby forming these compounds. It is a compound that has a functional group that can be cross-linked. In addition, compounds having a photo-crosslinking group also react with each other.

By using the liquid crystal aligning agent of the present invention containing the above polymerizable compound in a vertically aligned liquid crystal display element such as a SC-PVA type liquid crystal display, the side chain that vertically aligns the liquid crystal and the photoreactive side chain are formed. Compared to the case where the polymer or this polymerizable compound is used alone, the response speed can be significantly improved, and the response speed can be sufficiently improved even with a small amount of the polymerizable compound added.

The group to be photopolymerized or photocrosslinked includes a monovalent group represented by the following formula (IV).

In the formula, R ¹² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Z ¹ represents a divalent aromatic ring or heterocyclic ring that may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms. Z ² represents a monovalent aromatic ring or heterocycle that may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms.

[Formula 40]

Specific examples of the polymerizable compound include a compound having a photopolymerizable group at each of two terminals represented by the following formula (V), a terminal having a photopolymerizable group represented by the following formula (VI), and a terminal having a photocrosslinking group. and compounds having a photocrosslinking group at each of the two terminals represented by the following formula (VII).

Additionally, in the following formulas (V) to (VII), R ¹² , Z ¹ and Z ² are the same as R ¹² , Z ¹ and Z ² in the formula (IV), and Q ¹ is a divalent organic group. am. 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 -), and a cyclohexylene group (-C ₆ H ₁₀ -). It is desirable to have This is because interaction with the liquid crystal tends to increase.

[Formula 41]

[Formula 42]

[Formula 43]

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

[Formula 44]

In addition, even if it is a polymerizable compound that has an acrylate group or a methacrylate group rather than an α-methylene-γ-butyrolactone group as a group to be photopolymerized or photocrosslinked, the acrylate group or methacrylate group may be used as a spacer such as an oxyalkylene group. A polymerizable compound having a structure bonded to a phenylene group via , can significantly improve the response speed, as can the polymerizable compound having an α-methylene-γ-butyrolactone group at both terminals. In addition, polymerizable compounds having a structure in which an acrylate group or methacrylate group is bonded to a phenylene group through a spacer such as an oxyalkylene group have improved stability against heat and can be used at high temperatures, for example, at a firing temperature of 200°C or higher. It's bearable enough.

The method for producing the polymerizable compound is not particularly limited, and can be produced, for example, according to the following synthesis example. For example, the polymerizable compound represented by the above formula (R-1) is produced by the method proposed by Talaga et al. in P. Talaga, M. Schaeffer, C. Benezra and JL Stampf, Synthesis, 530 (1990), which is represented by the following reaction formula: It can be synthesized by reacting 2-(bromomethyl)acrylic acid (2-(bromomethyl)propenoic acid) with aldehyde or ketone using SnCl ₂ . Additionally, Amberlyst 15 is a strongly acidic ion exchange resin manufactured by Rohm & Haas.

In addition, in the formula below, R' represents a monovalent organic group.

[Formula 45]

In addition, 2-(bromomethyl)acrylic acid is represented by the following reaction formula by Ramaran et al. in K. Ramarajan, K. Kamalingam, D. J. O'Donnell and K. D. Berlin, Organic Synthesis, vol.61, 56-59 (1983) It can be synthesized using the proposed method.

[Formula 46]

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

[Formula 47]

[Formula 48]

In addition, when synthesizing a polymerizable compound represented by the above formula (R-1) in which R ¹ and R ² are different, a method represented by the following reaction formula can be used.

[Formula 49]

When synthesizing a polymerizable compound in which V and W are single bonds in the above formula (R-1), a method represented by the following reaction formula can be used.

[Formula 50]

＜Synthesis of polyamic acid＞

When obtaining a polyamic acid by reaction of a diamine component and tetracarboxylic dianhydride, a known synthesis method can be used. Generally, this is a method of reacting a diamine component and a tetracarboxylic dianhydride component in an organic solvent. The reaction between the diamine component and tetracarboxylic dianhydride is advantageous in that it proceeds relatively easily in an organic solvent and does not generate by-products.

The organic solvent used in the above reaction is not particularly limited as long as it dissolves the produced polyamic acid. Furthermore, even if it is an organic solvent in which polyamic acid does not dissolve, it may be used by mixing with the solvent as long as the produced polyamic acid does not precipitate. Additionally, since moisture in the organic solvent inhibits the polymerization reaction and further causes hydrolysis of the produced polyamic acid, it is preferable to use a dehydrated and dried organic solvent.

Organic solvents used in the above reaction include, for example, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, N-methylformamide, N-methyl-2- Pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 3-methoxy-N,N-dimethylpropanamide, N-methylcapro Lactam, dimethyl sulfoxide, tetramethyl urea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, γ-butyrolactone, isopropyl alcohol, methoxymethyl pentanol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone. , methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol. , ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol. Monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, Dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3 -Methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, di Oxane, n-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, ethylene carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate Ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3-methoxypropionic acid propyl, 3 -Methoxypropionate butyl, diglyme, 4-hydroxy-4-methyl-2-pentanone, 2-ethyl-1-hexanol, etc. are mentioned. These organic solvents may be used individually or in combination.

The method of reacting the diamine component and the tetracarboxylic dianhydride component in an organic solvent is to stir a solution in which the diamine component is dispersed or dissolved in the organic solvent, and the tetracarboxylic dianhydride component is added as is or dispersed or dissolved in the organic solvent. A method of adding by dissolving, a method of adding the diamine component to a solution in which the tetracarboxylic acid dianhydride component is dispersed or dissolved in an organic solvent, or a method of adding the tetracarboxylic dianhydride component and the diamine component alternately, etc. It can be anything. In addition, when the diamine component or the tetracarboxylic dianhydride component consists of multiple types of compounds, they may be reacted in a pre-mixed state, may be reacted individually sequentially, or the individually reacted low molecular weight substances may be mixed and reacted to form a polymer. It may be used as a monomer.

The temperature when reacting the diamine component and the tetracarboxylic dianhydride component is, for example, -20°C to 150°C, and preferably is in the range of -5°C to 100°C. Moreover, for the reaction, for example, the total concentration of the diamine component and the tetracarboxylic dianhydride component is preferably 1 to 50% by mass, and more preferably 5 to 30% by mass with respect to the reaction liquid.

The ratio of the total number of moles of the tetracarboxylic dianhydride component to the total number of moles of the diamine component in the polymerization reaction can be selected according to the molecular weight of the polyamic acid to be obtained. As in a typical polycondensation reaction, the closer this molar ratio is to 1.0, the larger the molecular weight of the polyamic acid produced is, and a preferable range is 0.8 to 1.2.

The method for synthesizing the polyamic acid used in the present invention is not limited to the above method, and like the general method for synthesizing polyamic acid, instead of the tetracarboxylic dianhydride, tetracarboxylic acid or tetracarboxylic acid of the corresponding structure is used. The corresponding polyamic acid can also be obtained by using a tetracarboxylic acid derivative such as acid dihalide and reacting it by a known method.

Methods for imidizing the above-described polyamic acid to produce a polyimide include thermal imidization in which a solution of the polyamic acid is heated as is, and catalytic imidization in which a catalyst is added to the polyamic acid solution. In addition, the imidization rate from polyamic acid to polyimide does not necessarily need to be 100%.

The temperature when thermally imidizing a polyamic acid in a solution is 100°C to 400°C, preferably 120°C to 250°C, and is preferably carried out while removing water generated by the imidization reaction to the outside of the system.

Catalyst imidization of the polyamic acid can be performed by adding a basic catalyst and an acid anhydride to a solution of the polyamic acid and stirring the solution at -20 to 250°C, preferably 0 to 180°C. The amount of the basic catalyst is 0.5 to 30 mole times the amic acid group, preferably 2 to 20 mole times, and the amount of the acid anhydride is 1 to 50 mole times the amic acid group, preferably 3 to 30 mole times. Basic catalysts include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine, and among them, pyridine is preferable because it has an appropriate basicity to proceed with the reaction. Examples of acid anhydrides include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Among these, acetic anhydride is preferred because it facilitates purification after completion of the reaction. The imidization rate by catalyst imidization can be controlled by adjusting the catalyst amount, reaction temperature, and reaction time.

In addition, polyamic acid ester is prepared by reacting tetracarboxylic acid diester dichloride with a diamine similar to the synthesis of the polyamic acid above, or by reacting tetracarboxylic acid diester with the same diamine as the synthesis of the polyamic acid above in the presence of a suitable condensing agent or base. It can be manufactured by reacting under the following conditions. In addition, it can also be obtained by synthesizing polyamic acid in advance using the above method and esterifying the carboxylic acid in the amic acid using a polymer reaction. Specifically, for example, tetracarboxylic acid diester dichloride and diamine are reacted in the presence of a base and an organic solvent at -20°C to 150°C, preferably 0°C to 50°C, for 30 minutes to 24 hours, preferably. Polyamic acid ester can be synthesized by reacting for 1 hour to 4 hours. Polyimide can also be obtained by heating the polyamic acid ester at a high temperature to promote dealcoholization and ring closure.

When recovering polyimide precursors or polyimides such as polyamic acid and polyamic acid ester produced from the reaction solution, the reaction solution may be added to a poor solvent to cause precipitation. Poor solvents used for precipitation include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and water. The polymer precipitated by adding it to a poor solvent can be recovered by filtration and then dried under normal or reduced pressure, at room temperature, or by heating. Additionally, if the recovered polymer is re-dissolved in an organic solvent and the reprecipitation and recovery operation is repeated 2 to 10 times, impurities in the polymer can be reduced. Examples of poor solvents at this time include alcohols, ketones, hydrocarbons, etc., and it is preferable to use three or more types of poor solvents selected from these because the purification efficiency further increases.

＜Liquid crystal alignment agent＞

Although the liquid crystal aligning agent of this invention contains the said polyimide precursor, content of the polyimide precursor is preferable 1-20 mass %, More preferably, it is 3-15 mass %, Especially preferably, it is 3-10 mass %. % am. Moreover, when containing a polymerizable compound each having a photopolymerizable or photocrosslinking group at two or more terminals, the content is preferably 1 to 50 parts by mass, more preferably 5 to 30 parts by mass, with respect to 100 parts by mass of the polymer. It is the mass part.

Moreover, the liquid crystal aligning agent of this invention may contain other polymers other than the said polyimide precursor. At that time, the content of these other polymers in all polymer components is preferably 0.5 to 80 mass%, more preferably 20 to 50 mass%.

The molecular weight of the polymer possessed by the liquid crystal aligning agent is the weight average molecular weight measured by GPC (Gel Permeation Chromatography) method when considering the strength of the liquid crystal alignment film obtained by applying the liquid crystal aligning agent, workability at the time of forming the coating film, and uniformity of the coating film. It is preferably 5,000 to 1,000,000, and more preferably 10,000 to 150,000.

The solvent contained in the liquid crystal aligning agent is not particularly limited, and contains components such as the polyimide precursor and, if necessary, polymerizable compounds each having a photopolymerizable or photocrosslinkable group at two or more terminals, which are dissolved or dispersed. Anything you can do is fine. For example, organic solvents as exemplified in the synthesis of polyamic acid can be mentioned. Among them, N-methyl-2-pyrrolidone, γ-butyrolactone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 3-methoxy-N,N- Dimethylpropanamide is preferable in terms of solubility. Of course, a mixed solvent of two or more types may be used.

Moreover, it is preferable to mix and use the solvent which improves the uniformity and smoothness of a coating film with a solvent in which the component containing a liquid crystal aligning agent has high solubility. Such solvents include, for example, isopropyl alcohol, methoxymethylpentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, and ethyl cellosolve acetate. , butylcarbitol, ethylcarbitol, ethylcarbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene. Glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl Ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3- Methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, di Isobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene acetate. Glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3-methoxypropionic acid. Propyl, 3-methoxybutyl propionate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, Propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol, methyl lactate ester , ethyl lactic acid, n-propyl lactic acid, n-butyl lactic acid, isoamyl lactic acid, 2-ethyl-1-hexanol, etc. You may mix multiple types of these solvents. 5-80 mass % of the whole solvent contained in a liquid crystal aligning agent is preferable, and, as for these solvents, 20-60 mass % is more preferable.

The liquid crystal aligning agent may contain components other than those mentioned above. Examples include compounds that improve film thickness uniformity and surface smoothness when the liquid crystal aligning agent is applied, and compounds that improve the adhesiveness of the liquid crystal aligning film and the substrate.

Compounds that improve film thickness uniformity and surface smoothness include fluorine-based surfactants, silicone-based surfactants, and nonionic surfactants. More specifically, for example, Ftop EF301, EF303, EF352 (manufactured by Tochem Products), Megapak F171, F173, R-30 (manufactured by Dainippon Ink), Fluorad FC430, FC431 (manufactured by Sumitomo 3M) , Asahi Guard AG710, Suplon S-382, SC101, SC102, SC103, SC104, SC105, and SC106 (manufactured by Asahi Glass Co., Ltd.). The usage 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 the total amount of the polymer contained in the liquid crystal aligning agent.

Specific examples of compounds that improve the adhesion between the liquid crystal alignment film and the substrate include 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-ethoxy Carbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine Amine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl Acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3- Aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis(oxyethylene)-3-aminopropyltrimethoxysilane, N-bis(oxyethylene)-3-aminopropyltri Ethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diyl. Glycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl ether Cydyl-2,4-hexanediol, N,N,N',N'-tetraglycidyl-m-xylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane , N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, 3-(N-allyl-N-glycidyl)aminopropyltrimethoxysilane, 3-( N,N-diglycidyl)aminopropyltrimethoxysilane, etc. are mentioned.

Additionally, in order to further increase the film strength of the liquid crystal alignment film, phenol compounds such as 2,2'-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane and tetra(methoxymethyl)bisphenol may be added. 0.1-30 mass parts is preferable with respect to the total amount of 100 mass parts of polymers contained in a liquid crystal aligning agent, and 1-20 mass parts of these compounds are more preferable.

In addition, to the liquid crystal aligning agent, you may add a dielectric or a conductive substance for the purpose of changing the electrical properties such as dielectric constant and conductivity of the liquid crystal aligning film as long as it is a range in which the effect of the present invention is not impaired other than the above.

By applying this liquid crystal aligning agent on a substrate and baking it, a liquid crystal alignment film that vertically aligns the liquid crystal can be formed. By use of the liquid crystal aligning agent of this invention, the response speed of the liquid crystal display element using the liquid crystal aligning film obtained can be made fast. Moreover, the polymerizable compound which has the group which photopolymerizes or photocrosslinks at two or more terminals, which may be contained in the liquid crystal aligning agent of this invention, is not contained in a liquid crystal aligning agent, or is contained in a liquid crystal together with a liquid crystal aligning agent. , even in the so-called PSA mode, the light reaction is highly sensitive, and a tilt angle can be provided even with a small amount of ultraviolet irradiation.

For example, after apply|coating the liquid crystal aligning agent of this invention to a board|substrate, it dries as needed, and the cured film obtained by baking can also be used as a liquid crystal aligning film as it is. In addition, this cured film can be rubbed, irradiated with polarized light or light of a specific wavelength, treated with an ion beam, etc., or UV can be irradiated with a voltage applied to the liquid crystal display element after liquid crystal charging as an alignment film for PSA. . In particular, it is useful to use as an alignment film for PSA.

At this time, the substrate used is not particularly limited as long as it is a highly transparent substrate, and includes glass plates, polycarbonate, poly(meth)acrylate, polyether sulfone, polyarylate, polyurethane, polysulfone, polyether, and polyether ketone. , trimethylpentene, polyolefin, polyethylene terephthalate, (meth)acrylonitrile, triacetylcellulose, diacetylcellulose, acetate butyrate cellulose, etc. can be used. In addition, it is preferable from the viewpoint of process simplification to use a substrate on which ITO electrodes for driving liquid crystal are formed. Additionally, in a reflective liquid crystal display device, even an opaque material such as a silicon wafer can be used as long as it is used for only one side of the substrate, and a light-reflecting material such as aluminum can also be used as the electrode in this case.

The application method of the liquid crystal aligning agent is not particularly limited, and includes printing methods such as screen printing, offset printing, and flexo printing, inkjet methods, spray methods, roll coat methods, dip, roll coater, slit coater, and spinner. there is. In terms of productivity, the transfer printing method is widely used industrially, and is also preferably used in the present invention.

The coating film formed by applying the liquid crystal aligning agent by the above method can be baked to form a cured film. The drying process after applying the liquid crystal aligning agent is not necessarily necessary, but it is preferable to perform the drying process when the time from application to baking is not constant for each substrate, or when baking is not performed immediately after application. This drying only requires that the solvent has been removed to the extent that the shape of the coating film is not deformed by transportation of the substrate, etc., and the drying means is not particularly limited. For example, a method of drying on a hot plate at a temperature of 40°C to 150°C, preferably 60°C to 100°C, is used for 0.5 minutes to 30 minutes, preferably for 1 minute to 5 minutes.

The baking temperature of the coating film formed by applying a liquid crystal aligning agent is not limited, and is, for example, 100 to 350°C, preferably 120 to 300°C, and more preferably 150 to 250°C. The firing time is 5 minutes to 240 minutes, preferably 10 minutes to 90 minutes, and more preferably 20 minutes to 90 minutes. Heating can be performed by a commonly known method, for example, a hot plate, a hot air circulation furnace, an infrared furnace, etc.

Moreover, the thickness of the liquid crystal aligning film obtained by baking is not specifically limited, but is preferably 5 to 300 nm, and more preferably 10 to 100 nm.

＜Liquid crystal display device＞

The liquid crystal display element of the present invention can produce a liquid crystal cell by a known method after forming a liquid crystal alignment film on a substrate by the above method. A specific example of the liquid crystal display element is a liquid crystal cell having two substrates arranged to face each other, a liquid crystal layer formed between the substrates, and the liquid crystal alignment film formed between the substrate and the liquid crystal layer and formed with the liquid crystal aligning agent of the present invention. It is a vertically aligned liquid crystal display device equipped with a. Specifically, a liquid crystal alignment film is formed by applying the liquid crystal aligning agent of the present invention onto two substrates and baking them, the two substrates are arranged so that the liquid crystal alignment films face each other, and a liquid crystal layer composed of liquid crystal is formed between the two substrates. It is a liquid crystal display element of a vertical alignment type including a liquid crystal cell produced by sandwiching, that is, contacting a liquid crystal alignment film to form a liquid crystal layer, and irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer.

Using a liquid crystal aligning film formed with the liquid crystal aligning agent of the present invention, ultraviolet rays are irradiated while applying a voltage to the liquid crystal aligning film and the liquid crystal layer to polymerize the polymerizable compound, and the photoreactive side chains that the polymer has, By reacting the photoreactive side chain of the polymer with the polymerizable compound, the orientation of the liquid crystal is fixed more efficiently, resulting in a liquid crystal display element with significantly excellent response speed.

The substrate used in the liquid crystal display device of the present invention is not particularly limited as long as it is a substrate with high transparency, but is usually a substrate on which a transparent electrode for driving liquid crystal is formed. Specific examples include the same substrate as the liquid crystal alignment film described above. A substrate on which a conventional electrode pattern or a protrusion pattern is formed may be used, but in the liquid crystal display device of the present invention, since the liquid crystal aligning agent of the present invention is used, for example, a line/slit of 1 to 10 μm is formed on one side of the substrate. It is possible to operate even in a structure in which an electrode pattern is formed and a slit pattern or protrusion pattern is not formed on the opposing substrate. By using a liquid crystal display device with this structure, the manufacturing process can be simplified and high transmittance can be obtained. there is.

Additionally, in high-performance devices such as TFT-type devices, devices such as transistors formed between an electrode for driving liquid crystal and a substrate are used.

In the case of a transmissive liquid crystal display device, it is common to use a substrate as described above, but in a reflective liquid crystal display device, an opaque substrate such as a silicon wafer can also be used as long as it is only on one side of the substrate. At that time, a material such as aluminum that reflects light may be used for the electrode formed on the substrate.

The liquid crystal material constituting the liquid crystal layer of the liquid crystal display device of the present invention is not particularly limited, and is a liquid crystal material used in a conventional vertical alignment method, for example, negative liquid crystal such as MLC-6608 or MLC-6609 manufactured by Merck & Co. can be used. In addition, in PSA mode, for example, a liquid crystal containing a polymerizable compound as represented by the following formula can be used.

[Formula 51]

In the present invention, known methods can be used as a method of sandwiching the liquid crystal layer between two substrates. For example, prepare a pair of substrates on which a liquid crystal alignment film is formed, spacers such as beads are spread on the liquid crystal alignment film of one substrate, and the other substrate is bonded so that the surface on the side on which the liquid crystal alignment film is formed is inside. (貼合) and a method of injecting liquid crystal under reduced pressure and sealing it. In addition, a pair of substrates on which a liquid crystal alignment film was formed was prepared, and spacers such as beads were spread on the liquid crystal alignment film of one of the substrates, and then the liquid crystal was dropped so that the surface on the side on which the liquid crystal alignment film was formed was inside, and the other substrate was placed on the liquid crystal alignment film. A liquid crystal cell can also be produced by bonding one side of the substrate and sealing it. The thickness of the spacer is preferably 1 to 30 μm, more preferably 2 to 10 μm.

The process of manufacturing a liquid crystal cell by irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer includes, for example, applying an electric field to the liquid crystal alignment film and the liquid crystal layer by applying a voltage between electrodes provided on a substrate, and One example is a method of irradiating ultraviolet rays while maintaining an electric field. Here, the voltage applied between the electrodes is, for example, 5 to 30 Vp-p, preferably 5 to 20 Vp-p. The amount of ultraviolet irradiation is, for example, 1 to 60 J, preferably 40 J or less. A smaller amount of ultraviolet irradiation can suppress the decrease in reliability caused by destruction of the members constituting the liquid crystal display element, and can also suppress the irradiation of ultraviolet rays. This is desirable because manufacturing efficiency increases by reducing time.

As described above, when ultraviolet rays are irradiated while applying a voltage to the liquid crystal alignment film and 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 tilt angle can be set to the desired value, and the response speed can also be fastened. Moreover, when ultraviolet rays are irradiated while applying voltage to the liquid crystal alignment film and the liquid crystal layer, a polyimide precursor having a side chain that vertically aligns the liquid crystal and a photoreactive side chain, and a polyimide obtained by imidizing this polyimide precursor Since the photoreactive side chains of at least one type of polymer selected from the above or the photoreactive side chains of the polymer react with the polymerizable compound, the response speed of the resulting liquid crystal display element can be increased.

The pretilt angle of the liquid crystal display element depends on the liquid crystal alignment film used, that is, the liquid crystal aligning agent used, the polyimide precursor used, and the first photo radical-generating diamine used. As described above, by using the polyimide precursor of the present invention, especially a polyimide precursor with a relatively large amount of radical generation, the amount of radical generation during UV irradiation increases. In addition, as the amount of radical generation increases, the reaction of the polymerizable compound described above is promoted, so that, in the case of the same wavelength, the pretilt angle of the liquid crystal display element obtained with a small irradiation amount can be set to a desired value, and the response speed can be increased. You can.

Generally, the pretilt angle of a liquid crystal display element tends to move away from 90° as the amount of UV irradiation increases when forming the liquid crystal display element.

Example

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited at all to these examples.

In addition, the abbreviations and structures of the compounds and the measurement methods for each characteristic are as follows.

(menstruum)

DMF: N,N-dimethylformamide

THF: tetrahydrofuran

NMP: N-methyl-2-pyrrolidone

BCS: Butylcellosolve

(diamine)

DA-A: 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-methoxy-2-methylpropan-1-one

DA-1: 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropan-1-one

DA-2: 4-(4-(4-heptylcyclohexyl)phenoxy)benzene-1,3-diamine

3AMPDA: 3,5-diamino N-(pyridin-3-ylmethyl)benzamide

(acid dianhydride)

BODA: Bicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic acid dianhydride

CBDA: 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride

(additive)

3AMP: 3-picolylamine

[Formula 52]

[ ^1H NMR]

Device: Fourier transform superconducting nuclear magnetic resonance (FT-NMR) INOVA-400 (manufactured by Varian) 400 MHz

Solvent: deuterated chloroform (CDCl ₃ ), or deuterated dimethyl sulfoxide (DMSO-d ₆ )

Standard material: tetramethylsilane (TMS)

Number of integrations: 8, or 32.

[ ^13C { ^1H }NMR]

Device: Fourier transform superconducting nuclear magnetic resonance (FT-NMR) INOVA-400 (manufactured by Varian) 100 MHz

Solvent: deuterated chloroform (CDCl ₃ ), or deuterated dimethyl sulfoxide (DMSO-d ₆ )

Standard material: tetramethylsilane (TMS)

Accumulated count: 256.

[Molecular Weight]

The molecular weight of the polyimide precursor and its imidized polymer is measured by GPC (room temperature gel permeation chromatography) equipment, and is calculated as the number average molecular weight (hereinafter also referred to as Mn) and weight average molecular weight ( Hereinafter, also referred to as Mw) was calculated.

GPC device: Room temperature gel permeation chromatography (GPC) device (SSC-7200) manufactured by Senshu Science Co., Ltd.

Column: manufactured by Shodex (serial of KD803, KD805)

Column temperature: 50℃

Eluent: N,N-dimethylformamide (as additives, lithium bromide-hydrate (LiBr·H ₂ O) is 30 mmol/l, phosphoric acid/anhydrous crystal (o-phosphoric acid) is 30 mmol/l, tetrahydrofuran (THF) ) this 10 ㎖/ℓ)

Flow rate: 1.0 mL/min.

Standard sample for creating a calibration curve: TSK standard polyethylene oxide manufactured by Tosoh (weight average molecular weight (Mw) approximately 900,000, 150,000, 100,000, 30,000), and polyethylene glycol manufactured by Polymer Laboratories (peak top molecular weight (Mp) approximately 12,000, 4,000). , 1,000). To avoid overlapping peaks, two samples were measured separately: a sample mixed with 900,000, 100,000, 12,000, and 1,000, and a sample mixed with 150,000, 30,000, and 4,000.

[Measurement of imidization rate]

The imidization rate of the polyimide in the synthesis example was measured as follows. 20 mg of polyimide powder was placed in an NMR sample tube (NMR sampling tube standard, ϕ5 (manufactured by Cusano Scientific)), and deuterated dimethyl sulfoxide (DMSO-d ₆ , 0.05% TMS (tetramethylsilane) mixture) (1.0 ml) ) was added and ultrasonic waves were applied to completely dissolve it. Proton NMR of this solution was measured at 500 MHz using an NMR measuring instrument (JNW-ECA500) (manufactured by Nippon Electronics Datum). The imidization rate is determined by determining a proton derived from a structure that does not change before and after imidization as a reference proton, and the peak integrated value of this proton and the integrated peak value of the proton derived from the NH group of amidic acid appearing around 9.5 ppm to 10.0 ppm. It was obtained using the formula below.

Imidation rate (%) = (1 - α·x/y) × 100

In the above formula, x is the proton peak integration value derived from the NH group of amidic acid, y is the peak integration value of the reference proton, and α is the NH of amidic acid in the case of polyamic acid (imidation rate of 0%). It is the ratio of the number of standard protons to one basic proton.

[Synthesis of diamine compounds]

(Control Synthesis Example 1: Synthesis of aromatic diamine compound (DA-1))

[Formula 53]

Step 1: Synthesis of 1-(4-(2,4-dinitrophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropanone

In a 2 liter four-necked flask equipped with a stirrer and a nitrogen introduction tube, 100.0 g ([Mw: 186.10 g/mol], 0.538 mol) of 2,4-dinitrofluorobenzene, 2-hydroxy-4'- (2-Hydroxyethoxy)-2-methylpropiophenone, 120.6 g ([Mw: 224.25 g/mol], 0.538 mol), triethylamine, 81.7 g ([Mw: 101.19 g/mol], 0.807 mol) ), 1000 g of THF was added, and the mixture was refluxed for 24 hours. After completion of the reaction, it was concentrated using a rotary evaporator, ethyl acetate was added, and this was washed several times with pure water and physiological saline solution, and then dried over anhydrous magnesium sulfate.

Anhydrous magnesium sulfate was removed by filtration, concentrated with a rotary evaporator, and then recrystallized with ethyl acetate and n-hexane to obtain 157.0 g of a milky white substance ([Mw: 390.34 g/mol], 0.402 mol, yield: 75%). ) was obtained. This was confirmed by nuclear magnetic resonance spectrum ( ^1H -NMR spectrum) of the hydrogen atom in the molecule. The measurement data is shown below.

Step 2: Synthesis of 1-(4-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropanone (DA-1)

Weigh 100.0 g ([Mw: 390.34 g/mol], 0.256 mol) of the dinitrobenzene derivative obtained in Step 1 and 10.0 g of iron-doped platinum carbon (3 wt% manufactured by Evonic) in a 1 liter four-necked flask. , 500 ml of THF was added, degassing under reduced pressure and hydrogen substitution were sufficiently performed, and reaction was performed at room temperature for 24 hours.

After completion of the reaction, platinum carbon was removed using a membrane filter made of PTFE, the filtrate was removed using a rotary evaporator, and solid was deposited. The obtained solid was heated and washed with isopropyl alcohol and dried under reduced pressure to obtain 72.7 g of the target compound, a light pink solid ([Mw: 330.38 g/mol], 0.220 mol yield: 86%). ¹ H-NMR spectrum measurement data is shown below.

<Synthesis Example 1>

Aromatic diamine compound (DA-A): Synthesis of 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-methoxy-2-methylpropan-1-one

An aromatic diamine compound (DA-A) was synthesized through the 5-step route shown below. In addition, the aromatic diamine compound (DA-A) corresponds to the specific diamine compound mentioned above.

Step 1: 2-Hydroxy-2-methyl-1-(4-(2-((tetrahydro-2H-pyran-2-yl)oxy)ethoxy)phenyl)propan-1-one (DA-A -1) Synthesis of

[Formula 54]

IRGACURE2959 (2-hydroxy-1-(4-(2-hydroxyethoxy)phenyl)-2-methylpropan-1-one, 50.0 g, 223 mmol) was dissolved in THF (200 g) and p- Toluenesulfonic acid monohydrate (0.424 g, 2.23 mmol) was added, and 3,4-dihydro-2H-pyran (23.4 g, 279 mmol) was added dropwise over 10 minutes and allowed to react at room temperature for 3 hours. Afterwards, the reaction solution was filtered and the filtrate was concentrated to obtain 2-hydroxy-2-methyl-1-(4-(2-((tetrahydro-2H-pyran-2-yl)oxy)ethoxy) A crude product of phenyl)propan-1-one was obtained (green liquid, 73.7 g).

Second step: 2-methoxy-2-methyl-1-(4-(2-((tetrahydro-2H-pyran-2-yl)oxy)ethoxy)phenyl)propan-1-one (DA-A -2) Synthesis of

[Formula 55]

Sodium hydride (57.1 wt% purity, 15.0 g, 357 mmol) was suspended in THF (448 g), cooled to 3°C, and the crude product of DA-A-1 (73.3 g) was dissolved in THF (138 g) to form a solution. It was added dropwise over 15 minutes at 3°C. After that, the mixture was stirred for 30 minutes, methyl iodide (41.0 g, 357 mmol) was added dropwise over 5 minutes, and the mixture was stirred at room temperature for 22 hours. Afterwards, water (660 g) and toluene (586 g) were added and stirred at room temperature in that order, the water layer was discarded, the organic layer was washed twice with water (650 g), and the organic layer was concentrated to obtain 2-meth. The crude product of Toxy-2-methyl-1-(4-(2-((tetrahydro-2H-pyran-2-yl)oxy)ethoxy)phenyl)propan-1-one was obtained (brown liquid, 80.1 g) .

Third step: Synthesis of 1-(4-(2-hydroxyethoxy)phenyl)-2-methoxy-2-methylpropan-1-one (DA-A-3)

[Formula 56]

To a solution of p-toluenesulfonic acid monohydrate (0.469 g, 2.46 mmol) dissolved in a mixed solvent of methanol (397 g) and THF (80 g), the crude product of DA-A-2 (79.4 g) was added to THF (79 g). ) was added over 3 minutes at room temperature. After that, the mixture was stirred for 2 hours, the reaction mixture was concentrated, and it was confirmed that 20% of the raw materials remained. Then, THF (350 g), water (290 g), and p-toluenesulfonic acid monohydrate (2.53 g, 13.3 mmol) were added to the residue, and the mixture was stirred at room temperature for 14 hours. After that, toluene (350 g) was added, and after stirring, the water layer was discarded, the organic layer was washed twice with water (340 g), and the organic layer was concentrated to obtain 1-(4-(2-hydroxyethoxy) The crude phenyl)-2-methoxy-2-methylpropan-1-one was obtained (brown liquid, 50.5 g).

Step 4: Synthesis of 1-(4-(2-(2,4-dinitrophenoxy)ethoxy)phenyl)-2-methoxy-2-methylpropan-1-one (DA-A-4)

[Formula 57]

The crude product of DA-A-3 (45.7 g) was dissolved in DMF (79.9 g), 1-fluoro-2,4-dinitrobenzene (35.7 g, 192 mmol), and triethylamine (29.1 g, 288 mmol) was added and stirred at room temperature for 24 hours. After that, toluene (274 g) and water (274 g) were added and stirred, the water layer was discarded, the organic layer was washed twice with water (274 g), and the organic layer was concentrated. Subsequently, the residue was purified by silica gel column chromatography (solvent: toluene/ethyl acetate = 3/1 (v/v), Rf = 0.3), and the eluate was concentrated. After that, 2-propanol (193 g) was added to the residue, stirred at room temperature, filtered, and again 2-propanol (400 g) was added to the filtrate, stirred and filtered at 60°C, and the filtrate was By drying, 1-(4-(2-(2,4-dinitrophenoxy)ethoxy)phenyl)-2-methoxy-2-methylpropan-1-one was obtained (light brown solid, 29.2 g, yield 30 % (4 steps)).

Step 5: Synthesis of 1-(4-(2-(2,4-dinitrophenoxy)ethoxy)phenyl)-2-methoxy-2-methylpropan-1-one (DA-A)

[Formula 58]

DA-A-4 (10.0 g, 24.7 mmol) was dissolved in THF, 1% platinum-carbon (0.2% Fe doped, 59.5 wt% water, 0.62 g) was added, and stirred under a hydrogen pressure of 0.2 to 0.5 MPa. . After 3 hours, completion of the reaction was confirmed by HPLC, the catalyst was filtered, the filtrate was concentrated, toluene (30 g) was added, stirred at 65°C for 30 minutes, cooled to 0°C, and the precipitated solid was filtered and dried to obtain 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-methoxy-2-methylpropan-1-one (purple solid, 7.23 g) , yield 85%)

(Examples 1 and 2)

＜Synthesis of liquid crystal aligning agent＞

BODA (10.01 g, 40.0 mmol), 3AMPDA (4.85 g, 20.0 mmol), DA-A (13.78 g, 40.0 mmol), DA-2 (15.22 g, 40.0 mmol) were dissolved in NMP (166.2 g), 60 After reacting at ℃ for 5 hours, CBDA (11.57 g, 59.0 mmol) and NMP (55.4 g) were added and reacted at 40℃ for 10 hours to obtain a polyamic acid solution.

After adding NMP to this polyamic acid solution (250 g) and diluting it to 6.5 mass%, acetic anhydride (45.9 g) and pyridine (14.2 g) were added as imidization catalysts, and the reaction was allowed to proceed at 70°C for 3 hours. This reaction solution was added to methanol (3300 ml), and the obtained precipitate was separated by filtration. This precipitate was washed with methanol, dried under reduced pressure at 100°C, and polyimide powder (A) was obtained. The imidation rate of this polyimide was 72%, the number average molecular weight was 14000, and the weight average molecular weight was 38000.

NMP (44.0 g) was added to the obtained polyimide powder (A) (6.0 g), and stirred at 70°C for 20 hours to dissolve. A liquid crystal aligning agent (A1) was obtained by adding 6.0 g of 3AMP (1 mass % NMP solution), NMP (4.0 g), and BCS (40.0 g) to this solution and stirring it at room temperature for 5 hours.

＜Production of liquid crystal cell＞

The liquid crystal cell was produced in the procedures as shown below using the liquid crystal aligning agent (A1) obtained in Example 1.

The liquid crystal aligning agent (A1) obtained in Example 1 was spin-coated on the ITO surface of an ITO electrode substrate on which an ITO electrode pattern with a pixel size of 100 μm × 300 μm and a line/space of 5 μm was formed, and the mixture was heated at 80°C. After drying for 90 seconds with a hot plate, baking was performed for 30 minutes in a hot air circulation oven at 200°C to form a liquid crystal alignment film with a film thickness of 100 nm.

In addition, the liquid crystal aligning agent (A1) is spin-coated on the ITO surface on which the electrode pattern is not formed, dried for 90 seconds on a hot plate at 80°C, and then baked in a hot air circulation oven at 200°C for 30 minutes. A liquid crystal alignment film with a film thickness of 100 nm was formed.

For the above two substrates, a 4 µm bead spacer was spread on the liquid crystal alignment film of one of the substrates, and then a sealant (solvent-type thermosetting type epoxy resin) was printed from thereon. Next, the surface of the other substrate on which the liquid crystal alignment film was formed was turned inward and bonded to the previous substrate, and then the sealant was cured to produce an empty cell. Liquid crystal MLC-3023 (trade name manufactured by Merck & Co., Ltd.) containing a polymerizable compound for PSA was injected into this empty cell by a reduced-pressure injection method to produce a liquid crystal cell.

＜Measurement of pretilt angle＞

＜＜UV irradiation: 6 J/㎠ or 10 J/㎠＞＞

With a DC voltage of 15 V applied to the obtained liquid crystal cell, the liquid crystal cell was irradiated with 6 J/cm 2 or 10 J/cm 2 of UV that had passed through a 365 nm band-pass filter from the outside of the liquid crystal cell. In addition, the UV illuminance was measured using UV-MO3A manufactured by ORC. Afterwards, for the purpose of deactivating unreacted polymerizable compounds remaining in the liquid crystal cell, UV (UV lamp: FLR40SUV32/A- 1) was irradiated for 30 minutes.

Afterwards, the pretilt angle of the pixel portion of the cell after UV irradiation was measured. In addition, the pretilt angle was measured using an LCD analyzer LCA-LUV42A manufactured by Mayo Technica. The results are shown in Table 1.

＜Measurement of response speed＞

First, in a measuring device comprised in that order of a backlight, a set of polarizers in a cross-Nicol state, and a light quantity detector, the obtained liquid crystal cell was placed between the sets of polarizers. At this time, the pattern of the ITO electrode with lines/spaces formed was set at an angle of 45° with respect to the cross nicol. Then, a square wave with a voltage of ±7 V and a frequency of 1 kHz is applied to the liquid crystal cell, the change in luminance observed by the light quantity detector until saturation is acquired with an oscilloscope, and the luminance when no voltage is applied is obtained. A voltage of 0%, ±7 V was applied, the saturated luminance value was set as 100%, and the time it took for the luminance to change from 10% to 90% was taken as the response speed.

(Control Examples 1 and 2)

＜Synthesis of control liquid crystal aligning agent＞

A control liquid crystal aligning agent (B1) was used in the same manner as in Example 1, except that instead of "DA-A (13.78 g, 40.0 mmol)" in Example 1, DA-1 (13.22 g, 40.0 mmol) was used. synthesized. Specifically, a control liquid crystal aligning agent (B1) was synthesized as follows.

That is, BODA (10.01 g, 40.0 mmol), 3AMPDA (4.85 g, 20.0 mmol), DA-1 (13.22 g, 40.0 mmol), DA-2 (15.22 g, 40.0 mmol) were dissolved in NMP (164.6 g) , After reacting at 60°C for 5 hours, CBDA (11.57 g, 59.0 mmol) and NMP (54.9 g) were added and reacted at 40°C for 10 hours to obtain a polyamic acid solution.

After adding NMP to this polyamic acid solution (250 g) and diluting it to 6.5% by mass, acetic anhydride (46.4 g) and pyridine (14.4 g) were added as imidization catalysts, and reaction was performed at 70°C for 3 hours. This reaction solution was added to methanol (3300 ml), and the obtained precipitate was separated by filtration. This precipitate was washed with methanol, dried under reduced pressure at 100°C, and polyimide powder (B) was obtained. The imidization rate of this polyimide was 73%, the number average molecular weight was 23000, and the weight average molecular weight was 64000.

NMP (44.0 g) was added to the obtained polyimide powder (B) (6.0 g), and stirred at 70°C for 20 hours to dissolve. 6.0 g of 3AMP (1% by mass NMP solution), NMP (4.0 g), and BCS (40.0 g) were added to this solution, and the liquid crystal aligning agent (B1) was obtained by stirring at room temperature for 5 hours.

＜Production of a control liquid crystal cell and measurement of its pretilt angle and response speed＞

A control liquid crystal cell was produced in the same manner as in Example 1, except that the liquid crystal aligning agent (B1) was used instead of the "liquid crystal aligning agent (A1)" in Example 1.

In addition, the same operation as in the examples was performed on the obtained control liquid crystal cell, and the pretilt angle and response speed were measured. The results are shown in Table 1.

From Table 1, the following can be seen.

That is, the control liquid crystal cells of Control Examples 1 and 2 (using the control liquid crystal aligning agent (B1) obtained using the control diamine (DA-1)) and Examples 1 and 2 (using the aromatic diamine compound (DA-A)) When comparing the liquid crystal cells of (using the liquid crystal aligning agent (A1)) obtained by doing, the pretilt angle of the liquid crystal cells of Examples 1 and 2 is distant from 90 degrees at the time of light irradiation of the same irradiation amount.

Moreover, it can be seen that the liquid crystal cells of Examples 1 and 2 can be provided with a desired pretilt angle and a desired response speed at a lower UV irradiation dose than the liquid crystal cells of Control Examples 1 and 2. This is because the amount of radicals generated during UV irradiation of the aromatic diamine compound (DA-A) used in the liquid crystal cells of Examples 1 and 2 is greater than that of the diamine (DA-1) used in the control liquid crystal cell.

Since the liquid crystal cells of Examples 1 and 2 require less UV irradiation at the same wavelength than the control liquid crystal cells of Control Examples 1 and 2, damage to the liquid crystal due to shortening of the UV irradiation time can be reduced, and it is possible to reduce the amount of UV irradiation in liquid crystal production. Costs can be controlled.

Claims (18)

A polyimide precursor using a first photo-radical generating diamine,
radicals upon light irradiation under the same conditions than the second polyimide precursor formed under the same conditions as the polyimide precursor except that the first photo-radical-generating diamine was changed to the second photo-radical-generating diamine represented by formula (1). Characterized by a large amount of occurrence,
[Formula 1]

The first photo-radical generating diamine is represented by formula (A)
(In the formula, Ar represents an aromatic hydrocarbon group that may have a substituent,
R ¹⁰¹ represents a divalent organic group,
R ¹⁰² to R ¹⁰⁴ each independently represent a monovalent organic group)
It has a structure of
[Formula 2]

Above -R ¹⁰¹ - A, -T ₁ -ST ₂ -
(During the ceremony,
T ₁ and T ₂ are each independently a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-,
S is a single bond, or an alkylene group with 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom (-CH ₂ - or -CF ₂ - in the alkylene group is -CH=CH-, or the following It may be substituted with a group selected from group G (however, groups selected from group G are not adjacent to each other) (group G: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring or a divalent heterocycle)))
It is expressed as
Among the above R ¹⁰² to R ¹⁰⁴ , any one is -OR ¹¹¹ (R ¹¹¹ is a straight or branched chain or cyclic alkyl group of 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom (among the alkyl groups) -CH ₂ - or -CF ₂ - may be substituted with -CH=CH- or a group selected from the following group G (however, the groups selected from the group G are not adjacent to each other) (group G: It may be substituted with -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring or a divalent heterocycle)),
The other two are each independently a straight chain or branched chain or cyclic alkyl group having 1 to 20 carbon atoms, -OR ¹¹² (R ¹¹² is a straight chain having 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom) or a group selected from the group consisting of a branched chain or cyclic alkyl group and an aryl group having 6 to 20 carbon atoms which may have a substituent), a benzyl group, or a phenethyl group (the other two are the alkyl group or -OR ¹¹² In this case, they may be combined with each other to form a ring), polyimide precursor. According to claim 1,
A polyimide precursor wherein the wavelength of light at the time of light irradiation is 300 nm to 400 nm. According to claim 1,
A polyimide precursor wherein the first photo radical-generating diamine is 0.1 to 100 mol% out of 100 mol% of all diamines constituting the polyimide precursor. According to claim 1,
A polyimide precursor wherein Ar is a phenylene group. According to claim 1,
A polyimide precursor in which the first photo-radical generating diamine is represented by the following formula (2) (wherein Ar and R ¹⁰¹ to R ¹⁰⁴ have the same definitions as described above).
[Formula 3]

According to claim 1,
A polyimide precursor in which the first photo-radical generating diamine is represented by the following formula (3).
[Formula 4]

According to claim 1,
A polyimide precursor that additionally has side chains that vertically align the liquid crystal. According to claim 1,
A polyimide precursor that further has a side chain containing a photoreactive group in its structure. A polyimide obtained by imidating the polyimide precursor according to any one of claims 1 to 8. A liquid crystal aligning agent having a polyimide obtained by imidizing the polyimide precursor according to any one of claims 1 to 8 and/or the polyimide precursor according to any one of claims 1 to 8. According to claim 10,
A liquid crystal aligning agent used in the manufacture of a liquid crystal display element, which contains a polymerizable compound in a liquid crystal and/or a liquid crystal alignment film, and is obtained by reacting the polymerizable compound by irradiating ultraviolet rays while applying a voltage. A liquid crystal aligning film formed with the liquid crystal aligning agent according to claim 10. A liquid crystal display element provided with the liquid crystal alignment film according to claim 12. The following formula (2) (wherein Ar represents an aromatic hydrocarbon group which may have a substituent,
R ¹⁰¹ represents a divalent organic group,
R ¹⁰² to R ¹⁰⁴ each independently represent a monovalent organic group)
It is expressed as
[Formula 5]

Above -R ¹⁰¹ - A, -T ₁ -ST ₂ -
(During the ceremony,
T ₁ and T ₂ are each independently a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-,
S is a single bond, or an alkylene group with 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom (-CH ₂ - or -CF ₂ - in the alkylene group is -CH=CH-, or the following It may be substituted with a group selected from group G (however, groups selected from group G are not adjacent to each other) (group G: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring or a divalent heterocycle)))
It is expressed as
Among the above R ¹⁰² to R ¹⁰⁴ , any one of them is -OR ¹¹¹ (R ¹¹¹ is a straight or branched chain or cyclic alkyl group of 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom (among the alkyl groups) -CH ₂ - or -CF ₂ - may be substituted with -CH=CH- or a group selected from the following group G (however, the groups selected from the group G are not adjacent to each other) (group G: It may be substituted with -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring or a divalent heterocycle)),
The other two are each independently a straight chain or branched chain or cyclic alkyl group having 1 to 20 carbon atoms, -OR ¹¹² (R ¹¹² is a straight chain having 1 to 20 carbon atoms that is unsubstituted or substituted with a fluorine atom) or a group selected from the group consisting of a branched chain or cyclic alkyl group and an aryl group having 6 to 20 carbon atoms which may have a substituent), a benzyl group, or a phenethyl group (the other two are the alkyl group or -OR ¹¹² In this case, they may be combined with each other to form a ring), diamine. Diamine represented by the following formula (3).
[Formula 6]

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