KR101884044B1 - Liquid crystal aligning agent, liquid crystal alignment film, liquid crystal display element, and method for manufacturing liquid crystal display element - Google Patents

Abstract

A polyimide having a photoreactive side chain containing a side chain that vertically aligns the liquid crystal and at least one selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, At least one kind of polymer selected from polyimides obtained by imidizing the polyimide precursor with a precursor and at least one kind of core selected from the following formulas (i-1) to (i-3) A polymerizable compound having a group capable of photopolymerizing or photo-crosslinking at its terminal and the photopolymerizable or photo-crosslinkable group being bonded directly or via a bonding group to the mother nucleus, and a liquid crystal aligning agent having a solvent.

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid crystal alignment film, a liquid crystal alignment film, a liquid crystal display device, and a manufacturing method of a liquid crystal display device. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal alignment film,

The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal display element, and a method for producing a liquid crystal display element which can be used for producing a liquid crystal display element of a vertical alignment type manufactured by irradiating ultraviolet rays while applying a voltage to liquid crystal molecules will be.

Among the liquid crystal display elements of the system (also referred to as a vertical alignment (VA) system) in which the liquid crystal molecules vertically aligned with respect to the substrate are caused to respond by an electric field, a process of irradiating ultraviolet rays while applying a voltage to the liquid crystal molecules .

In such a vertical alignment type liquid crystal display device, a photopolymerizable compound is added in advance to a liquid crystal composition and used together with a vertical alignment film such as polyimide to irradiate ultraviolet light while applying a voltage to the liquid crystal cell, (See, for example, Patent Document 1 and Non-Patent Document 1) are known (Polymer Sustained Alignment (PSA) type liquid crystal display). In general, the direction in which the liquid crystal molecules responding to an electric field is tilted is controlled by protrusions formed on the substrate or slits formed on the display electrodes, etc. However, by adding a photopolymerizable compound to the liquid crystal composition and applying a voltage to the liquid crystal cell, It is known that the response speed of the liquid crystal display element is improved as compared with a method of controlling the tilting direction of the liquid crystal molecules only by the protrusion or slit since the polymer structure in which the direction of tilting of the liquid crystal molecules is stored is formed on the liquid crystal alignment film.

In this PSA type liquid crystal display element, the solubility of the polymerizable compound to be added to the liquid crystal is low, and there is a problem that precipitation occurs at a low temperature when the addition amount is increased. On the other hand, if the amount of the polymerizable compound to be added is reduced, a favorable alignment state can not be obtained. In addition, since the unreacted polymerizable compound remaining in the liquid crystal becomes an impurity (contamination) in the liquid crystal, there is a problem that the reliability of the liquid crystal display element is lowered.

It has been reported that the response speed of a liquid crystal display device is improved even when a photopolymerizable compound is added to a liquid crystal alignment film not in a liquid crystal composition (SC-PVA type liquid crystal display) (see, for example, Non-Patent Document 2).

Japanese Patent Application Laid-Open No. 2003-307720

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

In such an SC-PVA mode, although the polymerizable compound is contained in the liquid crystal aligning agent, there is a problem that the storage stability of the liquid crystal aligning agent is poor and the component is precipitated. For example, even when the component is temporarily dissolved at the stage of producing the liquid crystal aligning agent, the component tends to precipitate when the liquid crystal aligning agent is cryopreserved. When this photopolymerizable compound is mixed in the liquid crystal when the liquid crystal display element is produced and remains unreacted, it becomes an impurity, which causes the reliability of the liquid crystal display element to deteriorate.

It is also desirable to increase the response speed of the liquid crystal display element by increasing the addition amount of the photopolymerizable compound. However, when the addition amount of the photopolymerizable compound is increased, There is a problem that stability becomes worse.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art and it is an object of the present invention to provide a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal display element, and a liquid crystal display element which can improve the response speed of a liquid crystal display element of a vertical alignment system, And a method of manufacturing the display element.

The liquid crystal aligning agent of the present invention for solving the above problems is a liquid crystal aligning agent which has a side chain for vertically orienting a liquid crystal and at least one kind selected from methacrylic group, acrylic group, vinyl group, allyl group, coumarin group, styryl group and cinnamoyl group (I-1) to (i-3), at least one kind of polymer selected from the group consisting of a polyimide precursor having a photoreactive side chain containing a polyimide precursor and a polyimide obtained by imidizing the polyimide precursor, At least one kind of core selected from the group consisting of a polymerizable compound having a photopolymerizable or photocrosslinkable group at one or more terminals and a photopolymerizable or photo crosslinkable group directly or through a bonding group to the core nucleus and a solvent .

[Chemical Formula 1]

The polymerizable compound is preferably selected from the following formulas.

(2)

(Wherein, R ³¹ represents a single bond or -R ³⁵ O-, R ³⁵ is an alkylene group having a carbon number of 1 to 10 straight-chain, R ³² represents a single bond or -OR ³⁶ - represented by, R ³⁶ is straight An alkylene group having 1 to 10 carbon atoms in the chain, and R ³³ and R ³⁴ each independently represent a hydrogen atom or a methyl group)

Another liquid crystal aligning agent of the present invention is a liquid crystal aligning agent containing at least one member selected from a side chain for vertically orienting a liquid crystal and a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styrene group and a cinnamoyl group (Ii) at least one kind of polymer selected from polyimide precursors having photoreactive side chains and polyimide obtained by imidizing the polyimide precursor, and at least one kind of polymer selected from the following formulas (ii-1) to Characterized by having at least one core nucleus and a polymerizable compound having a photopolymerizable or photocrosslinkable group at one or more ends and the photopolymerizable or photocrosslinkable group being bonded to the core nucleus with an oxyalkylene group and a solvent.

(3)

The polymerizable compound is preferably selected from the following formulas.

[Chemical Formula 4]

(Wherein R ⁴¹ is a single bond or -R ⁴⁵ O-, R ⁴⁵ is an alkylene group having 1 to 10 carbon atoms in the linear chain, R ⁴² is a single bond or -OR ⁴⁶ -, and R ⁴⁶ is a direct bond An alkylene group having 1 to 10 carbon atoms in the chain, and R ⁴³ and R ⁴⁴ are each independently a hydrogen atom or a methyl group)

It is preferable that the side chain of the photoreactive group contains a group selected from the following formula (I).

[Chemical Formula 5]

(Wherein R < ¹¹ > is H or a methyl group)

It is preferable that the photopolymerization or photo-crosslinking group is selected from the following formula (II).

[Chemical Formula 6]

(Wherein R ¹² is H or an alkyl group having 1 to 4 carbon atoms, Z ¹ is a bivalent aromatic ring or heterocyclic ring which may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms, and Z ² is a monovalent aromatic ring or heterocyclic ring which may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms)

The liquid crystal alignment film of the present invention is characterized in that the liquid crystal aligning agent is applied to a substrate and fired.

The liquid crystal display element of the present invention includes a liquid crystal cell prepared by forming a liquid crystal layer in contact with a liquid crystal alignment film obtained by applying and firing the liquid crystal aligning agent to a substrate and irradiating ultraviolet rays while applying a voltage to the liquid crystal layer .

In the method of manufacturing a liquid crystal display element of the present invention, a liquid crystal layer is formed by contacting the liquid crystal alignment agent obtained by applying the liquid crystal aligning agent to a substrate and firing, and applying ultraviolet rays while applying a voltage to the liquid crystal layer, .

According to the present invention, it is possible to provide a liquid crystal aligning agent capable of improving the response speed of a liquid crystal display element and having excellent storage stability.

Hereinafter, the present invention will be described in detail.

The liquid crystal aligning agent of the present invention is a liquid crystal aligning agent containing a side chain for vertically orienting a liquid crystal and a photoreactive compound containing at least one selected from a methacrylic group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, (I-1) to (i-3), and at least one polymer selected from polyimides obtained by imidizing the polyimide precursor and at least one polymer selected from polyimides (Ii) a polymerizable compound having a group capable of photopolymerizing or photo-crosslinking at one or more ends thereof, and the photopolymerizable or photo-crosslinkable group being bonded directly or through a linking group to the parent nucleus, and / (ii-3), and a polymerizable compound having a group capable of photopolymerizing or photo-crosslinking at one or more ends and a group in which a photopolymerizable or photo-crosslinkable group is bonded with a mother nucleus and an oxyalkylene group And a solvent. The liquid crystal aligning agent is a solution for producing a liquid crystal alignment film, and the liquid crystal alignment film is a film for aligning the liquid crystal in a predetermined direction, in the present invention, in the vertical direction.

First, the polymerizable compound contained in the liquid crystal aligning agent of the present invention will be described in detail. The liquid crystal aligning agent of the present invention comprises at least one kind of core selected from the above formulas (i-1) to (i-3) and a group capable of photopolymerization or photo-crosslinking at one or more terminals, (Hereinafter referred to as " polymerization having a mother nucleus represented by the formulas (i-1) to (i-3)) bonded directly or via a bonding group to the mother nucleus represented by the above formulas (i- Compound "). ≪ / RTI > That is, the polymerizable compound contained in the liquid crystal aligning agent of the present invention has one or more terminals having a photopolymerizable or photocrosslinkable group, and the photopolymerizable or photocrosslinkable group is selected from the above-mentioned formulas (i-1) to (i-3) Is bonded directly or via a bonding group to at least one structure (mother nucleus).

The liquid crystal aligning agent of the present invention may be used together with the polymerizable compound having a mother nucleus represented by the above formulas (i-1) to (i-3) (Ii-1) to (ii-3), and a group capable of photopolymerizing or photo-crosslinking at one or more ends and having a group capable of undergoing photopolymerization or photocrosslinking (Hereinafter also referred to as a polymerizable compound having a macromolecule represented by formulas (ii-1) to (ii-3)) bonded with a gigamo nucleus and an oxyalkylene group .

The polymerizable compound having a photopolymerizable group is a compound having a functional group that causes polymerization by irradiation of light. The compound having a photocrosslinking group is a compound having a photocrosslinking group that reacts with at least one polymer selected from a polymer of a polymerizable compound, a polyimide precursor, and a polyimide obtained by imidizing the polyimide precursor, And a functional group capable of crosslinking. The compound having a group capable of photo-crosslinking also reacts with the compound having a group capable of photo-crosslinking.

The polymerizable compound having a mother nucleus represented by the formulas (i-1) to (i-3) and the polymerizable compound having a mother nucleus represented by the formulas (ii-1) to (ii-3) Includes a side chain that vertically aligns the liquid crystal described later and a photoreactive side chain containing at least one selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, and a cinnamoyl group And a polyimide obtained by imidizing the polyimide precursor together with at least one kind of polymer in a liquid crystal aligning agent to form a liquid crystal display element of a vertical alignment type such as an SC-PVA type liquid crystal display It is possible to obtain a dramatically improved response speed as compared with the case of using a polymer having side chains and photoreactive side chains vertically orienting the liquid crystal and these polymerizable compounds alone Can be improved, the response time to a fast liquid crystal display device. Further, the amount of the polymerizable compound to be added can sufficiently improve the response speed at least. The liquid crystal aligning agent of the present invention can be obtained by polymerizing a polymerizable compound having a mother nucleus represented by the above formulas (i-1) to (i-3) or a polymerizable compound having a mother nucleus represented by the above formulas (ii- Compared with the case where a polymerizable compound other than a polymerizable compound is used, for example, a polymerizable compound having a biphenyl structure as a mother nucleus, the storage stability at the time of cryopreservation (for example, when cryopreserved at about -20 캜) And becomes an excellent liquid crystal aligning agent.

The photopolymerization or photo-crosslinking group includes a monovalent group represented by the formula (II).

Specific examples of the polymerizable compound having a mother nucleus represented by the above formulas (i-1) to (i-3) and the polymerizable compound having a mother nucleus represented by the above formulas (ii-1) to (ii- A compound having a group capable of photopolymerizing at each of two terminals as represented by the following formula (III), a compound having a terminal having a group capable of photo-crosslinking with a terminal having a photopolymerizable group as shown by the following formula (IV) V), each of which has a group capable of photo-crosslinking. Further, according to the following formula (III) ~ (V), R 12, Z 1 and Z ² are the same as R ^12, Z ¹ and Z ² in the formula (II), and Q ¹ is the formula (i (Ii-1) to (ii-3), or a divalent organic group having an oxyalkylene group bonded to both ends of the structure represented by the above formulas (ii-1) to to be. It is preferable that Q ¹ has an oxyalkylene group or an alkylene group. This is because the interaction with the liquid crystal tends to become large.

(7)

[Chemical Formula 8]

[Chemical Formula 9]

Specific examples of the polymerizable compound having a mother nucleus represented by the above formulas (i-1) to (i-3) include compounds represented by the following formulas.

[Chemical formula 10]

(Wherein, R ³¹ represents a single bond or -R ³⁵ O-, R ³⁵ is an alkylene group having a carbon number of 1 to 10 straight-chain, R ³² represents a single bond or -OR ³⁶ - represented by, R ³⁶ is straight An alkylene group having 1 to 10 carbon atoms in the chain, and R ³³ and R ³⁴ each independently represent a hydrogen atom or a methyl group)

Specific examples of the polymerizable compound having a mother nucleus represented by the above formulas (ii-1) to (ii-3) include compounds represented by the following formulas.

(11)

(Wherein R ⁴¹ is a single bond or -R ⁴⁵ O-, R ⁴⁵ is an alkylene group having 1 to 10 carbon atoms in the linear chain, R ⁴² is a single bond or -OR ⁴⁶ -, and R ⁴⁶ is a direct bond An alkylene group having 1 to 10 carbon atoms in the chain, and R ⁴³ and R ⁴⁴ are each independently a hydrogen atom or a methyl group)

Generally, the process of forming a liquid crystal alignment layer includes a step of firing at a high temperature in order to completely remove the solvent. However, a polymerizable compound having an? -Methylene-? -Butyrolactone group as a polymerizable group (photopolymerizable group) , It is possible to withstand a structure in which the thermosynthesized structure is deteriorated or a firing temperature at a high temperature, for example, 200 ° C or more. Further, even when a polymerizable compound having an acrylate group or a methacrylate group other than an? -Methylene-? -Butyrolactone group as a photopolymerizable or photo-crosslinkable group is used, the acrylate group or the methacrylate group may also include a spacer such as an oxyalkylene group A polymerizable compound having a structure bonded to a phenylene group is preferable because the stability against heat is improved as in the case of the polymerizable compound having an? -Methylene-? -Butyrolactone group at the terminal thereof, Lt; 0 > C or more.

The method for producing such a polymerizable compound is not particularly limited and can be produced, for example, according to a synthesis example described later. For example, the polymerizable compound can be synthesized by combining the techniques in organic synthesis chemistry. For example, SnCl ₂ can be used to synthesize 2- (bromomethyl) thiophene by the method proposed by Targa et al. In T. Talaaga, M. Schaeffer, C. Benezra and JL Stampf, Synthesis, ) Acrylic acid (2- (bromomethyl) propenoic acid) with an aldehyde or a ketone. Amberlyst 15 is a strongly acidic ion exchange resin manufactured by Rohm and Haas.

[Chemical Formula 12]

(Wherein R 'represents a monovalent organic group)

In addition, 2- (bromomethyl) acrylic acid can be prepared by the method disclosed in K. Ramarajan, K. Kamalingam, DJO Donnell and KDBerlin, Organic Synthesis, vol. 61, 56-59 (1983) . ≪ / RTI >

[Chemical Formula 13]

The liquid crystal aligning agent of the present invention can be obtained by polymerizing a polymerizable compound having a mother nucleus represented by the above formulas (i-1) to (i-3) May contain two or more kinds of polymerizable compounds.

In addition to the polymerizable compound having a mother nucleus represented by the above formulas (i-1) to (i-3) or the polymerizable compound having a mother nucleus represented by the above formulas (ii-1) to (ii- (I-1) to (i-3) and a polymerizable compound other than the polymerizable compound having a mother nucleus represented by the above formulas (ii-1) to Hereinafter also referred to as " other polymerizable compound ").

Examples of the photopolymerization or photocrosslinking group of the other polymerizable compound include a monovalent group represented by the formula (II).

Specific examples of the other polymerizable compound include a compound having a group capable of photopolymerizing at each of two terminals as represented by the following formula (XV), a terminal having a photopolymerizable group as shown by the following formula (XVI) And a compound having a group capable of photo-crosslinking at each of two terminals as shown by the following formula (XVII). In the formulas (XV) to (XVII), R ¹⁷ is H or an alkyl group having 1 to 4 carbon atoms, and Z ³ is an alkyl group having 1 to 12 carbon atoms or an alkyl group having 2 to 12 carbon atoms optionally substituted with an alkoxy group having 1 to 12 carbon atoms Z ⁴ is a monovalent aromatic ring or heterocyclic ring which may be substituted by an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. Q ² does not have a structure represented by the above formulas (i-1) to (i-3), and an oxyalkylene group is bonded to both ends of the structure represented by the above formulas (ii- Is not a bivalent organic group. Q ² is a group having a cyclic structure such as a phenylene group (-C ₆ H ₄ -), a biphenylene group (-C ₆ H ₄ -C ₆ H ₄ -) or a cyclohexylene group (-C ₆ H ₁₀ -) . This is because the interaction with the liquid crystal tends to become large.

[Chemical Formula 14]

[Chemical Formula 15]

[Chemical Formula 16]

The polymerizable compound represented by the formula (XV) includes a polymerizable compound represented by the following formula (XVIII). In formula (XVIII), V ¹ is a single bond or -R ²¹ O-, R ²¹ is a linear or branched alkylene group having 1 to 10 carbon atoms, W ¹ is a single bond or -OR ²² - , R ²² is a linear or branched alkylene group having 1 to 10 carbon atoms, and R ¹⁸ is a hydrogen atom or a methyl group.

[Chemical Formula 17]

Specific examples of the compound represented by the formula (XVIII) include a polymerizable compound represented by the following formula.

[Chemical Formula 18]

(Wherein R < ¹⁸ > is H or a methyl group)

The method for producing such another polymerizable compound is also not particularly limited. For example, the polymerizable compound can be synthesized by combining the techniques in organic synthesis chemistry. As a specific synthesis example, for example, in the case of the formula (XV), it can be synthesized by the reaction of the following formula. In the following reaction formulas, R ¹⁹ and R ²⁰ are each independently a linear or branched alkylene group having 1 to 10 carbon atoms. THF is an abbreviation of tetrahydrofuran.

[Chemical Formula 19]

[Chemical Formula 20]

[Chemical Formula 21]

The liquid crystal aligning agent of the present invention is a liquid crystal aligning agent comprising at least one kind selected from a polyimide precursor and a polyimide obtained by imidizing the polyimide precursor, a polymer having a side chain that vertically aligns the liquid crystal and a photoreactive side chain Lt; / RTI > Examples of the polyimide precursor include polyamic acid (also referred to as polyamic acid), polyamic acid ester, and the like.

The side chain for vertically orienting the liquid crystal contained in the polymer is not limited as long as it is capable of orienting the liquid crystal perpendicularly to the substrate. For example, the side chain may have a ring structure or a branch structure in the middle of the long- A group having a fluorine atom or a group having a fluorine atom substituted with a part or all of the hydrogen atoms of these groups, and the like. Of course, the liquid crystal may have two or more types of side chains for vertically orienting the liquid crystal. The side chain for vertically orienting the liquid crystal may be directly bonded to a polyimide precursor such as polyamic acid or polyamic acid ester, or a main chain of polyimide, that is, a polyamic acid skeleton or a polyimide skeleton. Further, . Examples of the side chain for vertically orienting the liquid crystal include a hydrocarbon group having 8 to 30 carbon atoms, preferably 8 to 22 carbon atoms, in which a hydrogen atom may be substituted with fluorine, specifically, an alkyl group, a fluoroalkyl group, A naphthyl group, a phenethyl group, a styrylalkyl group, a naphthyl group, and a fluorophenylalkyl group. Examples of the side chain for vertically orienting other liquid crystals include those represented by the following formula (a).

[Chemical Formula 22]

(In the formula (a), l, m and n each independently represent an integer of 0 or 1, and R ³ represents an alkylene group having 2 to 6 carbon atoms, -O-, -COO-, -OCO-, -NHCO- , -CONH-, or an alkylene-ether group having 1 to 3 carbon atoms, R ⁴ , R ⁵ and R ⁶ each independently represent a phenylene group or a cycloalkylene group, and R ⁷ represents a hydrogen atom, An alkyl group or a fluorine-containing alkyl group, a monovalent aromatic ring, a monovalent aliphatic ring, a monovalent heterocyclic ring, or a monovalent large ring-

R ³ in the formula (a) is preferably -O-, -COO-, -CONH-, or an alkylene-ether group having 1 to 3 carbon atoms, from the viewpoint of ease of synthesis.

R ⁴ , R ⁵ and R ⁶ in the formula (a) are preferably 1, m, n, R ⁴ , R ⁵ and R ⁶ shown in the following Table 1 from the viewpoints of ease of synthesis and ability to orient the liquid crystal vertically ⁶ is preferable.

When at least one of l, m and n is 1, R ⁷ in the formula (a) is preferably a hydrogen atom or an alkyl group having 2 to 14 carbon atoms or a fluorine-containing alkyl group, more preferably a hydrogen atom or a An alkyl group having 1 to 12 carbon atoms or a fluorine-containing alkyl group. In addition, l, m, when n are both zero, R ⁷ is preferably a carbon number of 12 to 22 alkyl group or a fluorine-containing alkyl group, a monovalent aromatic ring, a monovalent aliphatic cyclic, monovalent heterocyclic ring, a monovalent made of their And is more preferably an alkyl group or a fluorine-containing alkyl group having 12 to 20 carbon atoms.

The amount of the side chain that vertically aligns the liquid crystal is not particularly limited as long as the liquid crystal alignment film can orient the liquid crystal vertically. However, in the liquid crystal display device having the liquid crystal alignment film, the abundance of the side chains for vertically orienting the liquid crystal within the range that does not hinder the display characteristics of the device, such as the voltage holding ratio and the accumulation of the residual DC voltage, .

The ability of a polymer having a side chain to vertically orient liquid crystals to vertically orient liquid crystals differs depending on the structure of side chains vertically orienting liquid crystals, but generally, the amount of side chains that vertically orient liquid crystals The ability to align the liquid crystal vertically is increased, and when it is decreased, it is lowered. In addition, when a cyclic structure is provided, the ability to vertically align the liquid crystal tends to be higher than in the case where the cyclic structure is not provided.

The polymer comprising at least one of a polyimide precursor and a polyimide such as polyamic acid or polyamic acid ester contained in the liquid crystal aligning agent of the present invention has a photoreactive side chain. The photoreactive side chain is a side chain having a functional group capable of forming a covalent bond by reaction with light such as ultraviolet (UV) (hereinafter, also referred to as a photoreactive group). In the present invention, As the genital group, it contains at least one member selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group. As described above, when a polymer comprising at least one of a polyimide precursor and a polyimide such as polyamic acid or polyamic acid ester contained in a liquid crystal aligning agent is used as a polymerizable monomer in the presence of a methacrylic group, an acryl group, a vinyl group, an allyl group, a coumarin group, And having a photoreactive side chain containing at least one kind selected from a neomoyl group and being used in the liquid crystal aligning agent together with the above polymerizable compound, as shown in Examples described later, the response speed is remarkably improved .

The photoreactive side chains may be directly bonded to the main chain of the polyimide precursor or polyimide, or they may be bonded via a suitable bonding group. Examples of the side chains of photoreactive groups include those represented by the following formula (b).

(23)

(In the formula (b), R ⁸ represents a single bond or -CH ₂ -, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N (CH ₃ ) -, -CON (CH ₃ ) - or -N (CH ₃ ) CO-, R ⁹ represents a single bond or an alkyl having 1 to 20 carbon atoms which is substituted by an unsubstituted or fluorine atom -CH ₂ - in the alkylene group may be optionally substituted by -CF ₂ - or -CH═CH-, and in the case where any of the groups shown below are not adjacent to each other, these groups may be substituted; R ¹⁰ is a group selected from the group consisting of a methacryl group, an acryl group, a vinyl group, an allyl group, a vinyl group, an allyl group, Coumarin group, styryl group, and cinnamoyl group)

R ⁸ in the formula (b) may be formed by a conventional organic synthetic method, but from the viewpoint of ease of synthesis, -CH ₂ -, -O-, -COO-, -NHCO-, -NH- , -CH ₂ O-.

Specific examples of the carbon ring or heterocyclic ring of the divalent carbon ring or the divalent heterocyclic ring substituting any -CH ₂ - in R ⁹ include, but are not limited to, the following structures .

≪ EMI ID =

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

The above formula (b) is more preferably a structure containing a group selected from the above formula (I).

The existing amount of the photoreactive side chain is preferably within a range capable of accelerating the response speed of the liquid crystal by reacting with ultraviolet light to form a covalent bond. In order to accelerate the response speed of the liquid crystal, As much as possible within a range that does not cause a problem. For example, the introduction amount of the photoreactive side chain to the polyimide precursor or polyimide is preferably 10 to 70 mol%, more preferably 20 to 60 mol%, particularly preferably 30 to 50 mol%.

A side chain for vertically orienting the liquid crystal and a photoreactive side chain containing at least one selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group The method for producing at least one kind of polymer selected from a polyimide precursor and a polyimide obtained by imidizing the polyimide precursor is not particularly limited. For example, by reacting a diamine with a tetracarboxylic acid dianhydride In the method for obtaining polyamic acid, a diamine having a side chain that vertically aligns the liquid crystal or a tetracarboxylic acid dianhydride having a side chain that vertically aligns the liquid crystal, a methacrylic group, an acrylic group, a vinyl group, an allyl group , A diamine having a photoreactive side chain containing at least one kind selected from a coumarin group, a styryl group and a cinnamoyl group, A tetracarboxylic acid dianhydride having a photoreactive side chain containing at least one member selected from the group consisting of a hydroxyl group, a hydroxyl group, a hydroxyl group, a hydroxyl group, a hydroxyl group, a hydroxyl group, a carboxyl group,

Examples of the diamine having a side chain that vertically aligns the liquid crystal include a long-chain alkyl group, a hydrocarbon group such as a group having a ring structure or branched structure or a steroid group in the middle of the long-chain alkyl group, or a part or all of hydrogen atoms in these groups A diamine having a fluorine atom-substituted group as a side chain, for example, a diamine having a side chain represented by the above formula (a). More specifically, for example, a diamine having a hydrocarbon group of 8 to 30 carbon atoms in which a hydrogen atom may be substituted with fluorine, or a diamine represented by the following formulas (2), (3), (4) But the present invention is not limited thereto.

(25)

(1, m, n, and R ³ to R ⁷ in the formula (2) are the same as in the formula (a)

(26)

(In the formulas (3) and (4), A ₁₀ represents -COO-, -OCO-, -CONH-, -NHCO-, -CH ₂ -, -O-, -CO- or -NH- , A ₁₁ represents a monovalent bond or a phenylene group, a represents the same structure as the side chain for vertically orienting the liquid crystal represented by the formula (a), and a 'represents the liquid crystal represented by the formula (a) Represents a divalent group having a structure in which one element of hydrogen or the like is separated from the same structure as the side chain to be subjected to hydrogenation)

(27)

(In the formula (5), A ₁₄ is an alkyl group having 3 to 20 carbon atoms which may be substituted with a fluorine atom, A ₁₅ is a 1,4-cyclohexylene group or a 1,4-phenylene group, A ₁₆ is an oxygen atom , or -COO- * (However, the coupling hand provided with an "*" is bonded with a ₁₅₎ and, a ₁₇ is a bond hand provided with an oxygen atom, -COO- or - (However, "*" (CH ₂ ) is coupled with a ₂ a). Further, a ₁ is an integer of 0 or 1, a ₂ is an integer of 2 ~ 10, a ₃ represents an integer of 0 or 1)

The bonding position of two amino groups (-NH ₂ ) in the formula (2) is not limited. Specifically, examples of the bonding group of the side chain include positions 2, 3, 2, 4, 2, 5, 2, 6, 3, 4, 3, 5 on the benzene ring. Among them, 2, 4 position, 2, 5 position, or 3, 5 position is preferable from the viewpoint of reactivity when synthesizing polyamic acid. When the ease of synthesis of the diamine is also added, positions 2 and 4, or positions 3 and 5 are more preferable.

Specific examples of the formula (2) include diamines represented by the following formulas [A-1] to [A-24], but the present invention is not limited thereto.

(28)

(In the formulas [A-1] to [A-5], A ₁ is an alkyl group having 2 to 24 carbon atoms or a fluorine-

[Chemical Formula 29]

(In the formulas [A-6] and [A-7], A ₂ represents -O-, -OCH ₂ -, -CH ₂ O-, -COOCH ₂ - or -CH ₂ OCO- and A ₃ Is an alkyl group having 1 to 22 carbon atoms, an alkoxy group, a fluorine-containing alkyl group or a fluorine-containing alkoxy group)

(30)

(In the formulas [A-8] to [A-10], A ₄ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O -, -OCH ₂ -, or -CH ₂ -, and A ₅ is an alkyl group, an alkoxy group, a fluorine-containing alkyl group or a fluorine-containing alkoxy group having 1 to 22 carbon atoms)

(31)

(Wherein [A-11] and the equation [A-12] of, A ₆ is -COO-, -OCO-, -CONH-, -NHCO-, -COOCH 2 -, -CH 2 OCO-, -CH 2 O _{-, -OCH 2 -, -CH 2} -, -O-, or represents a -NH-, a ₇ is a fluorine group, a cyano group, a trifluoromethane group, a nitro group, an azo group, a formyl group, acetyl group, acetoxy Or a hydroxyl group)

(32)

(In the formulas [A-13] and [A-14], A ₈ is an alkyl group having 3 to 12 carbon atoms and the cis-trans isomer of 1,4-cyclohexylene is a trans isomer)

(33)

(In the formulas [A-15] and [A-16], A ₉ is an alkyl group having 3 to 12 carbon atoms and the cis-trans isomer of 1,4-cyclohexylene is a trans isomer)

(34)

Specific examples of the diamine represented by the formula (3) include diamines represented by the following formulas [A-25] to [A-30], but are not limited thereto.

(35)

(Wherein [A-25] ~ formula [A-30] of, A ₁₂ is -COO-, -OCO-, -CONH-, -NHCO-, -CH 2 -, -O-, -CO-, or - NH-, and A ₁₃ represents an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group)

Specific examples of the diamine represented by the formula (4) include diamines represented by the following formulas [A-31] to [A-32], but the present invention is not limited thereto.

(36)

Among these, [A-1], [A-2], [A-3], [A-4], [A- 5], and [A-2] are preferable from the viewpoints of the ability to vertically align liquid crystals, Diamines of [A-25], [A-26], [A-27], [A- 28], [A- 29] and [A-

The diamine may be used alone or in combination of two or more, depending on the properties of the liquid crystal alignment layer, such as liquid crystal alignability, pretilt angle, voltage holding characteristics, and 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 the polyamic acid, more preferably 10 to 40 mol of the diamine component % Is a diamine having a side chain that vertically aligns the liquid crystal, and particularly preferably 15 to 30 mol%. The use of the diamine having a side chain for vertically orienting the liquid crystal in an amount of 5 to 50 mol% of the diamine component used for the synthesis of the polyamic acid is particularly excellent in terms of the response speed and the liquid crystal alignment immobilization ability.

Examples of the diamine having a photoreactive side chain containing at least one selected from the group consisting of a methacryl group, an acryl group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group include, for example, ). ≪ / RTI > More specifically, for example, diamines represented by the following general formula (6) can be mentioned, but the present invention is not limited thereto.

(37)

(Wherein R ⁸ , R ⁹ and R ^{10 in} the formula (6) are the same as in the formula (b)

The bonding position of two amino groups (-NH ₂ ) in the formula (6) is not limited. Specifically, examples of the bonding group of the side chain include positions 2, 3, 2, 4, 2, 5, 2, 6, 3, 4, 3, 5 on the benzene ring. Among them, 2, 4 position, 2, 5 position, or 3, 5 position is preferable from the viewpoint of reactivity when synthesizing polyamic acid. When the ease of synthesis of the diamine is also added, positions 2 and 4, or positions 3 and 5 are more preferable.

Specific examples of the diamine having a photoreactive side chain containing at least one member selected from the group consisting of a methacryl group, an acryl group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group include the following compounds But the present invention is not limited thereto.

(38)

(Wherein X is a single bond or a bonding group selected from -O-, -COO-, -NHCO-, -NH-, and Y is an alkylene group having 1 to 20 carbon atoms which is substituted by an unsubstituted or fluorine atom )

The diamine having a photoreactive side chain containing at least one selected from the methacryl group, the acrylic group, the vinyl group, the allyl group, the coumarin group, the styryl group and the cinnamoyl group has a liquid crystal alignment property, One type or two or more types may be used in combination depending on characteristics such as a pretilt angle, a voltage holding characteristic, an accumulated charge, and a response speed of liquid crystal when the liquid crystal display device is used.

The diamine having a photoreactive side chain containing at least one selected from the methacryl group, the acrylic group, the vinyl group, the allyl group, the coumarin group styryl group and the cinnamoyl group is used in the synthesis of polyamic acid It is preferably used in an amount of 10 to 70 mol%, more preferably 20 to 60 mol%, and particularly preferably 30 to 50 mol%, based on the diamine component.

In addition, as long as the effect of the present invention is not impaired, the polyamic acid may be used in combination with other diamines other than the diamines having a side chain for vertically orienting the liquid crystal or the diamine having a photoreactive group . Specific examples include p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m- , 4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, , 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminobiphenyl, 3,3'-dimethyl- 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'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 4,4'-diaminodiphenylmethane, 3'- , 3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diamino Diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3,4'-diaminodiphenyl ether, Bis (4-aminophenyl) silane, dimethyl-bis (4-aminophenyl) silane, -Aminophenyl) silane, dimethyl-bis (3-aminophenyl) silane, 4,4'-thiodianiline, 3,3'- thiodianiline, 4,4'- diaminodiphenylamine, - diaminodiphenylamine, 3,4'-diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, N-methyl (4,4'-dia (3,3'-diaminodiphenyl) amine, N-methyl (3,4'-diaminodiphenyl) amine, N-methyl (2,2'-diaminodiphenyl) Phenyl) amine, N-methyl (2,3'-diaminodiphenyl) amine, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 3,4'- 1,4-diaminonaphthalene, 2,2'-diaminobenzophene , 2,3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, Bis (4-aminophenyl) ethane, 1,2-bis (3-aminophenyl) ethane, 2,6-diaminonaphthalene, 2,6-diaminonaphthalene, Bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, ) Butane, bis (3,5-diethyl-4-aminophenyl) methane, 1,4-bis (4-aminophenoxy) benzene, (4-aminophenyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4 '- [1,4-phenylenebis (methylene)] dianiline, 4,4' - [ Phenylenebis (methylene)] dianiline, 3,3 '- [1,4-phenanthrene 1,4-phenylenebis [(4-aminophenyl) methanone], 1,4-phenylenebis (methylene)] dianiline, Phenylenebis [(3-aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone] Phenylenebis (4-aminobenzoate), 1,4-phenylenebis (3-aminobenzoate), 1,3- (3-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, bis , N, N '- (1,4-phenylene) bis (4-aminobenzamide) (4-aminobenzamide), N, N '- (1,3-phenylene) bis (3-aminobenzamide), N, N'- ) Terephthalamide, N, N'-bis (3-aminophenyl) terephthalate Bis (4-aminophenyl) isothiamides, N, N'-bis (3-aminophenyl) isophthalamide, 9,10- Bis [4- (4-aminophenoxy) phenyl] propane, 2,2'-bis [4- Bis (3-aminophenyl) hexafluoropropane, 2,2'-bis (3-aminophenyl) hexafluoropropane, 2,2'- Bis (3-aminophenyl) propane, 2,2'-bis (3-amino- Bis (4-aminophenoxy) propane, 1,3-bis (3-aminophenoxy) propane, Bis (4-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) Bis (4-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) Heptane, 1,7-bis (4-aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) , 1,9-bis (3-aminophenoxy) nonane, 1,10- (4-aminophenoxy) 1,10- (3-aminophenoxy) decane, 1,11- (3-aminophenoxy) undecane, 1,12- Aromatic diamines such as bis (4-aminophenoxy) dodecane and 1,12- (3-aminophenoxy) dodecane, bis (4-aminocyclohexyl) ) Methane, alicyclic diamines such as 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, Aliphatic diamines such as 8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane.

The other diamine may be used alone or in combination of two or more thereof depending on the properties such as liquid crystal alignability, pretilt angle, voltage holding property, and accumulated charge when the liquid crystal alignment film is used.

The tetracarboxylic acid dianhydride to be reacted with the above diamine component in the synthesis of the polyamic acid is not particularly limited. Specific examples include pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7-anthracene tetracarboxylic acid, 1,2,5,6-anthracene tetracarboxylic acid, 3,3 ', 4,4'-biphenyltetracarboxylic acid, 2,3,3 (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- (3,4-dicarboxyphenyl) propane, bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4-dicarboxyphenyl) diphenylsilane, 2,3,4,5- (3,4-dicarboxyphenyl) pyridine, 3,3 ', 4,4'-diphenylsulfone tetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid Acid, 1,3-diphenyl-1,2,3,4-cyclobutanetetracar Oxydipetetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexane Tetracarboxylic acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic acid, 1,2-dimethyl-1,2,3,4-cyclobutane tetracarboxyl Acid, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid, 1,2,3,4-cycloheptane tetracarboxylic acid, 2,3,4,5-tetrahydrofuran tetra Carboxylic acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene Succinic 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-ene-2,3,5,6-tetracarboxylic acid, 5- (2,5-dioxotetrahydrofuryl) -3-methyl- Dicarboxylic acid, tetracyclo [6,2,1,1,0,2,7] dodeca-4,5,9,10-tetracarboxylic acid, 3,5,6-tri Carboxynorbornane-2: 3,5: 6 dicarboxylic acid, and 1,2,4,5-cyclohexanetetracarboxylic acid. Of course, the tetracarboxylic acid dianhydride may be used alone or in combination of two or more, depending on the properties such as liquid crystal aligning property, voltage holding property, and accumulated charge when the liquid crystal alignment film is used.

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

The organic solvent used in the reaction is not particularly limited as long as it dissolves the produced polyamic acid. An organic solvent in which the polyamic acid does not dissolve may be mixed with the solvent in the range where the produced polyamic acid does not precipitate. In addition, water in the organic solvent inhibits the polymerization reaction, and further causes hydrolysis of the produced polyamic acid. Therefore, it is preferable to use an organic solvent that is dehydrated and dried. Examples of the organic solvent used in the reaction include N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylformamide, N-methylformamide, Pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 3-methoxy-N, N-dimethylpropanamide, N- But are not limited to, lactam, dimethylsulfoxide, tetramethylurea, pyridine, dimethylsulfone, hexamethyl sulfoxide,? -Butyrolactone, isopropyl alcohol, methoxymethyl pentanol, dipentene, ethyl amyl 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 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 mono Acetate, 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 Propylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, Diisobutylene, But are not limited to, ethyl acetate, butyl acetate, butyl acetate, butyl acetate, butyl acetate, butyl acetate, butyl acetate, butyl acetate, Propyleneglycol monoethyl ether, methyl pyruvate, methyl pyruvate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, methyl ethyl ketone, methyl lactate, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentanone, 2-ethyl-1-hexanol, and the like. These organic solvents may be used alone or in combination.

When the diamine component and the tetracarboxylic acid dianhydride component are reacted in an organic solvent, the solution in which the diamine component is dispersed or dissolved in an organic solvent is stirred and the tetracarboxylic acid dianhydride component is dispersed or dissolved in the organic solvent as it is A method of adding a diamine component to a solution in which a tetracarboxylic acid dianhydride component is dispersed or dissolved in an organic solvent, a method of alternately adding a tetracarboxylic acid dianhydride component and a diamine component, and the like Any of these methods may be used. When the diamine component or the tetracarboxylic acid dianhydride component is composed of a plurality of compounds, they may be reacted in a preliminarily mixed state, or they may be reacted individually or sequentially, and the low molecular weight compounds reacted individually are mixed and reacted, May be used.

The temperature at which the diamine component is reacted with the tetracarboxylic acid dianhydride component may be selected from any temperature, for example, from -20 ° C to 150 ° C, preferably from -5 ° C to 100 ° C. The reaction can be carried out at an arbitrary concentration. For example, the total amount of the diamine component and the tetracarboxylic acid dianhydride component relative to the reaction solution is 1 to 50% by mass, preferably 5 to 30% by mass.

The ratio of the total number of moles of the tetracarboxylic acid dianhydride component to the total number of moles of the diamine component in the above polymerization reaction can be selected in accordance with the molecular weight of the polyamic acid to be obtained. As in the case of the usual polycondensation reaction, the closer the molar ratio is to 1.0, the larger the molecular weight of the produced polyamic acid. It is 0.8 to 1.2 if it shows a preferable range.

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

Examples of the method of imidizing the polyamic acid to form polyimide include heat imidization in which a solution of polyamic acid is heated as it is, and catalyst imidation in which a catalyst is added to a solution of polyamic acid. In addition, the imidation rate from polyamic acid to polyimide does not necessarily have to be 100%.

The temperature at which the polyamic acid is thermally imidized in the solution is 100 ° C to 400 ° C, preferably 120 ° C to 250 ° C, and it is preferable to carry out the removal while removing the water generated by the imidization reaction out of the system.

The catalyst imidation of polyamic acid can be carried out by adding a basic catalyst and acid anhydride to a solution of polyamic acid and stirring at -20 to 250 ° C, preferably 0 to 180 ° C. The amount of the basic catalyst is 0.5 to 30 moles, preferably 2 to 20 moles, of the amide group, and the amount of the acid anhydride is 1 to 50 moles, preferably 3 to 30 moles, of the amide group. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine, etc. Among them, pyridine is preferred because it has a basicity suitable for proceeding the reaction. As the acid anhydride, acetic anhydride, trimellitic anhydride, pyromellitic anhydride and the like can be given. Among them, acetic anhydride is preferable because the purification after completion of the reaction becomes easy. The imidization rate by the catalyst imidization can be controlled by adjusting the catalyst amount, the reaction temperature, and the reaction time.

The polyamic acid ester may be produced by reacting a tetracarboxylic acid diester dichloride with a diamine which is the same as the synthesis of the polyamic acid or by reacting a diamine which is the same as the synthesis of the tetracarboxylic acid diester and the polyamic acid in the presence of a suitable condensing agent or base And the like. Alternatively, a polyamic acid may be synthesized in advance by the above-mentioned method, and a carboxylic acid in the polyamic acid may be esterified using a polymer reaction. Specifically, for example, the tetracarboxylic acid diester dichloride and the 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, And reacting for 1 hour to 4 hours, polyamic acid ester can be synthesized. The polyimide can also be obtained by heating the polyamic acid ester at a high temperature and promoting the alcohol to cause cyclization.

When a polyimide precursor such as polyamic acid or polyamic acid ester or a polyimide precursor or polyimide such as polyamic acid or polyamic acid ester produced from the reaction solution of polyimide is recovered, the reaction solution is added to a poor solvent To precipitate. Examples of the poor solvent used in the precipitation include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene and water. The polymer precipitated by charging into a poor solvent can be recovered by filtration and then dried at normal temperature or under reduced pressure or by heating. In addition, when the polymer precipitated and recovered is redissolved in an organic solvent, and the operation of re-precipitation and recovery is repeated 2 to 10 times, impurities in the polymer can be reduced. As the poor solvent at this time, for example, alcohols, ketones, hydrocarbons and the like can be exemplified, and when three or more poor solvents selected from these are used, the purification efficiency is further improved, which is preferable.

As described above, the liquid crystal aligning agent of the present invention is a liquid crystal aligning agent which has a side chain for vertically orienting a liquid crystal and at least one selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group (I-1) to (i-3), at least one polymer selected from the group consisting of a polyimide precursor having a photoreactive side chain containing a polyimide precursor and a polyimide obtained by imidizing the polyimide precursor, ) And / or a polymerizable compound having a mother nucleus represented by the above formulas (ii-1) to (ii-3) and a solvent, and the mixing ratio thereof is not particularly limited , The sum of the content of the polymerizable compound having a mother nucleus represented by the above formulas (i-1) to (i-3) and the content of the polymeric compound having a mother nucleus represented by the above formulas (ii-1) to , A side chain that vertically aligns the liquid crystal A polyimide precursor having a photoreactive side chain containing at least one member selected from the group consisting of a methacrylic group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group, Is preferably 1 to 50 parts by mass, more preferably 5 to 30 parts by mass, based on 100 parts by mass of the at least one polymer selected from polyimide obtained by polymerization. As described above, the liquid crystal aligning agent of the present invention can be obtained by polymerizing a polymerizable compound having a mother nucleus represented by the above-mentioned formulas (i-1) to (i-3) Is at least a sufficiently fast response speed. Since the liquid crystal aligning agent of the present invention is excellent in storage stability, the polymerizable compound having a mother nucleus represented by the above-mentioned formulas (i-1) to (i-3) Even if the addition amount of the polymerizable compound having a mother nucleus represented by ii-1) to ii-3) is somewhat increased, storage stability is good. The liquid crystal aligning agent may be a mixture of a side chain that vertically aligns the liquid crystal contained in the liquid crystal aligning agent and a side chain that contains at least one selected from methacryl group, acrylic group, vinyl group, allyl group, coumarin group, styryl group, The content of the at least one polymer selected from a polyimide precursor having reactive side chains and a polyimide obtained by imidizing the polyimide precursor is preferably 1% by mass to 20% by mass, more preferably 3% by mass % To 15% by mass, particularly preferably 3% by mass to 10% by mass.

The liquid crystal aligning agent of the present invention is a liquid crystal aligning agent containing at least one member selected from a side chain for vertically orienting a liquid crystal and a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group and a cinnamoyl group A polymer other than at least one polymer selected from a polyimide precursor having a photoreactive side chain and a polyimide obtained by imidizing the polyimide precursor may be contained. At this time, the content of such another polymer in the entire polymer component is preferably 0.5% by mass to 15% by mass, and more preferably 1% by mass to 10% by mass.

The molecular weight of the polymer having the liquid crystal aligning agent is preferably in the range of from 0.1 to 10 parts by weight based on the weight average measured by GPC (Gel Permeation Chromatography), considering the strength of the liquid crystal alignment film obtained by applying the liquid crystal aligning agent, The molecular weight is preferably 5,000 to 1,000,000, more preferably 10,000 to 150,000.

The solvent contained in the liquid crystal aligning agent is not particularly limited and includes a side chain for vertically orienting the liquid crystal and at least one selected from methacrylic group, acrylic group, vinyl group, allyl group, coumarin group, styryl group and cinnamoyl group (I-1) to (i-3), at least one kind of polymer selected from the group consisting of a polyimide precursor having a photoreactive side chain containing a species and a polyimide obtained by imidizing the polyimide precursor, (Ii-1) to (ii-3) and polymerizable compounds having a mother nucleus represented by the above formulas (ii-1) to (ii-3). For example, organic solvents as exemplified in the synthesis of the polyamic acid described above can be mentioned. Among them, N-methyl-2-pyrrolidone,? -Butyrolactone, N-ethyl-2-pyrrolidone, Dimethylpropanamide is preferable from the viewpoint of solubility. Of course, two or more types of mixed solvents may be used.

In addition, it is preferable to use a solvent which improves the uniformity and smoothness of the coating film in a solvent having high solubility of the component containing the liquid crystal aligning agent. Examples of the solvent that improves the uniformity and smoothness of the coating film include isopropyl alcohol, methoxymethyl pentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, butyl cell Propyleneglycol monobutylether, propyleneglycol monobutylether, propyleneglycol monoacetate, ethyleneglycol monobutylether, propyleneglycol monobutylether, propyleneglycol monoacetate, ethyleneglycol monobutylether, propyleneglycol monoacetate, Propylene glycol monomethyl ether, 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, 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- Propyl ether, diisobutyl ether, diisobutylene, amyl acetate, butyl butylate, butyl ether, diisobutyl ether, diisopropyl ether, diisopropyl ether, N-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol acetate Monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methylethyl 3-ethoxypropionate, 3- Methoxy-2-propanol, 1-ethoxy-2-propanol, 1-methoxypropionic acid, 3- 2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether- Ethyl lactate, n-butyl lactate, n-butyl lactate, isoamyl ester of lactic acid, 2-ethyl-1- (2-ethoxypropoxy) propanol, Hexanol, and the like. These solvents may be mixed with a plurality of kinds. When these solvents are used, it is preferably 5 to 80 mass%, more preferably 20 to 60 mass%, of the total solvent contained in the liquid crystal aligning agent.

The liquid crystal aligning agent may contain other components than those described above. Examples thereof include a compound which improves film thickness uniformity and surface smoothness when the liquid crystal aligning agent is applied, a compound which improves the adhesion between the liquid crystal alignment film and the substrate, a polymerization initiator and a polymerization inhibitor. The polymerization inhibitor is added in order to facilitate the handling of the polymerizable compound having high polymerizability.

Examples of the compound that improves film thickness uniformity and surface smoothness include a fluorine-based surfactant, a silicon-based surfactant, and a nonionic surface-active agent. More specifically, it is possible to use, for example, EF Top EF301, EF303 and EF352 (manufactured by Tohchem Products), Megafac F171, F173 and R-30 (manufactured by Dainippon Ink and Chemicals Inc.), Florad FC430 and FC431 (manufactured by Sumitomo 3M ), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.). When these surfactants are used, the use ratio thereof is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass based on 100 parts by mass of the total amount of the polymer contained in the liquid crystal aligning agent.

Specific examples of the compound that improves the adhesion between the liquid crystal alignment layer and the substrate include a functional silane-containing compound and an epoxy group-containing compound. For example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3 3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxy (2-aminoethyl) Aminopropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, 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- Bis (oxyethylene) -3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N- Aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neo Pentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6 -Tetraglycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N-diglycidylaminomethyl ) N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane, 3- (N, N-diglycidyl) And the like can be given no trimethoxysilane. In order to further increase the film strength of the liquid crystal alignment film, a phenol compound such as 2,2'-bis (4-hydroxy-3,5-dihydroxymethylphenyl) propane or tetra (methoxymethyl) bisphenol may be added . When these compounds are used, the amount is preferably from 0.1 to 30 parts by mass, more preferably from 1 to 20 parts by mass, based on 100 parts by mass of the total amount of the polymer contained in the liquid crystal aligning agent.

As the polymerization initiator, a radical polymerization initiator can be mentioned. Examples of the radical polymerization initiator include a compound comprising a benzoin derivative and a peroxide.

Preferred examples of the benzoin derivatives include (±) -camphaquinone, 2,2-diethoxyacetophenone, 2,4-diethylthioxanthene-9-one, 2-benzoylbenzoic acid, 2- 2-isopropylthioxanthone, 2-phenyl-2- (p-toluenesulfonyloxy) acetophenone, 4,4 ' Benzoyl benzoic acid, 4-benzoyl benzoic acid, 4-chlorobenzophenone, acetophenone, diphenyl ethanedione, benzoin, benzoin ethyl ether, benzoin isobutyl ether , Benzoin isopropyl ether, benzoin methyl ether, benzophenone, dibenzosuberone, 9-fluorenone, methyl 2-benzoylbenzoate, 4,4-dimethoxybenzoyl, 1- (4- -Dihydroxy-2-methylpropan-1-one, Michler's ketone, "DARACURE SERIES 1173, 4265", "IRGACURE SERIES 184, 500, 651, 819, 2959" manufactured by Chiba Specialty The There. A particularly preferred example of the benzoin derivative is Irgacure 651 manufactured by Chiba Specialty Co., Ltd.

Preferred examples of the peroxide compound include pertetra A, perhexa HC, perhexa C, perhexa V, perhexa 22, perbutyl D, perhexyl D, peryl 355 manufactured by Nichiyu Co., Perooyl L, Nippers BW, Nippers BMT, Peroyl TCP, Percumyl ND, Perocta ND, Perhexyl ND, Perbutyl NHP, Perhexyl PV, Perbutyl PV, Perhexa 25O, Peroocta O, There may be mentioned perbutyl O, perbutyl L, perbutyl 355, perhexyl I, perbutyl E, perhexa 25Z, perbutyl A, perhexyl Z, perbutyl Z and perbutyl ZT. Among the compounds composed of peroxides, particularly preferred examples include Perloil L, Knife BW, Knife BMT, perocta O, perhexyl O, perbutyl O, manufactured by Nichiyu Corporation.

Two or more of these polymerization initiators may be used in combination, and a preferable example of the combination is a mixture of benzophenone and Michler's ketone.

When a polymerization initiator is used, the use ratio thereof is preferably 10% by mass or less based on the total amount of the polymerizable compound, in order to prevent the polymerization initiator from acting as an impurity and degrading the display quality of the display element.

When the polymerization inhibitor is added, the use ratio thereof is preferably 10% by weight or less based on the total amount of the polymerizable compound in order to prevent the polymerization inhibitor from acting as an impurity.

The liquid crystal aligning agent may be added with a dielectric material or a conductive material for the purpose of changing electric characteristics such as dielectric constant and conductivity of the liquid crystal alignment film as long as the effect of the present invention is not impaired.

By applying this liquid crystal aligning agent on the substrate and baking it, a liquid crystal alignment film for vertically aligning the liquid crystal can be formed. The liquid crystal aligning agent of the present invention is a liquid crystal aligning agent containing a side chain for vertically orienting a liquid crystal and a photoreactive compound containing at least one selected from a methacrylic group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, (I-1) to (i-3), together with at least one polymer selected from the polyimide precursors having side chains of the polyimide precursor and the polyimide obtained by imidizing the polyimide precursor Since the polymerizable compound and the polymerizable compound having a mother nucleus represented by the above formulas (ii-1) to (ii-3) are present, the response speed of the liquid crystal display device using the resulting liquid crystal alignment film can be made fast. Further, the liquid crystal aligning agent of the present invention is excellent in storage stability, and precipitation of components is suppressed even in the case of cryopreservation. Therefore, a liquid crystal aligning agent can be prepared, and after cryopreservation, a liquid crystal alignment film can be produced.

For example, a cured film obtained by applying the liquid crystal aligning agent of the present invention to a substrate, drying it if necessary, and baking it may be used as a liquid crystal alignment film as it is. UV may be irradiated while rubbing the cured film, irradiating polarized light, light of a specific wavelength or the like, processing such as an ion beam, or applying an electric voltage to a liquid crystal display element after liquid crystal filling as an alignment film for SC-PVA It is possible.

In this case, the substrate to be used is not particularly limited as long as it is a substrate having high transparency and may be a glass plate, polycarbonate, poly (meth) acrylate, polyethersulfone, polyarylate, polyurethane, polysulfone, polyether, , Trimethylpentene, polyolefin, polyethylene terephthalate, (meth) acrylonitrile, triacetylcellulose, diacetylcellulose, cellulose acetate butyrate, and the like. In addition, it is preferable to use a substrate on which an ITO (Indium Tin Oxide) electrode for liquid crystal driving is formed from the viewpoint of simplifying the process. In a reflection type liquid crystal display element, if it is only a substrate on one side, it can be used as opaque silicon wafer or the like. In this case, a material that reflects light such as aluminum can also be used.

The method of applying the liquid crystal aligning agent is not particularly limited, and examples thereof include a printing method such as screen printing, offset printing and flexographic printing, an ink jet method, a spray method, a roll coating method, a dip, a roll coater, a slit coater, have. From the viewpoint of productivity, the transfer printing method is widely used industrially and is 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 step after the application of the liquid crystal aligning agent is not necessarily required, but it is preferable to carry out the drying step when the time from the application to the firing is not constant for each substrate, or when the firing is not performed immediately after application. The drying may be carried out as long as the solvent is removed to such an extent that the shape of the coated film is not deformed by transporting the substrate or the like, 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 for 0.5 minutes to 30 minutes, preferably for 1 minute to 5 minutes.

The baking temperature of the coating film formed by applying the liquid crystal aligning agent is not particularly limited and may be, for example, at any temperature of 100 to 350 ° C, preferably 120 to 300 ° C, 250 ° C. The firing time can be fired at any time between 5 minutes and 240 minutes. Preferably 10 minutes to 90 minutes, and more preferably 20 minutes to 90 minutes. The heating can be carried out by a commonly known method, for example, a hot plate, a hot air circulation path, an infrared ray or the like.

The thickness of the liquid crystal alignment film obtained by baking is not particularly limited, but is preferably 5 to 300 nm, and more preferably 10 to 120 nm.

The liquid crystal display element of the present invention can be obtained by forming a liquid crystal alignment film on a substrate by the above method, and then manufacturing a liquid crystal cell by a known method. Specific examples of the liquid crystal display element include a liquid crystal layer formed between the substrate and the liquid crystal layer, a liquid crystal layer formed between the substrate and the liquid crystal layer, and the liquid crystal alignment layer formed by the liquid crystal alignment agent of the present invention, Cell is a liquid crystal display element of a vertical alignment system. Specifically, a liquid crystal alignment film is formed by applying the liquid crystal aligning agent of the present invention on two substrates and firing, and two substrates are arranged so that the liquid crystal alignment films face each other. A liquid crystal layer And a liquid crystal cell which is manufactured by forming a liquid crystal layer by contacting with a liquid crystal alignment film and irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer. As described above, by using the liquid crystal alignment film formed by the liquid crystal alignment agent of the present invention, ultraviolet rays are irradiated while applying voltage to the liquid crystal alignment film and the liquid crystal layer to polymerize the polymerizable compound, and the photo- , By reacting the polymerizable compound with the photoreactive side chain of the polymer, the orientation of the liquid crystal is more efficiently fixed, and the liquid crystal display element is remarkably excellent in the response speed.

The substrate used in the liquid crystal display element of the present invention is not particularly limited as long as it is a substrate having high transparency, but is usually a substrate on which a transparent electrode for driving liquid crystal is formed. Specific examples include the same substrates as those described in the liquid crystal alignment film. A substrate on which a conventional electrode pattern or a projection pattern is formed may be used. In the liquid crystal display element of the present invention, since the liquid crystal aligning agent of the present invention is used as the liquid crystal aligning agent forming the liquid crystal alignment film, And a slit pattern or a protrusion pattern is not formed on the counter substrate, and the liquid crystal display device of this structure can be used for a manufacturing process And a high transmittance can be obtained.

In a high-performance device such as a TFT-type device, a device such as a transistor is formed between an electrode for liquid crystal driving and a substrate.

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

The liquid crystal alignment film is formed by applying the liquid crystal aligning agent of the present invention on this substrate and then firing, and the details are the same as described above.

The liquid crystal material constituting the liquid crystal layer of the liquid crystal display element of the present invention is not particularly limited and liquid crystal materials used in conventional vertical alignment methods such as MLC-6608 and MLC-6609 manufactured by Merck, Liquid crystal can be used.

As a method of sandwiching this liquid crystal layer between two substrates, known methods can be mentioned. For example, a pair of substrates on which a liquid crystal alignment film is formed is prepared, spacers such as beads are dispersed on a liquid crystal alignment film of one of the substrates, and the other substrate on the side where the liquid crystal alignment film is formed is inside And then the liquid crystal is injected under reduced pressure and sealed. A pair of substrates on which a liquid crystal alignment film is formed is prepared, a spacer such as beads is dispersed on a liquid crystal alignment film of one of the substrates, the liquid crystal is dropped, and then the side on the side where the liquid crystal alignment film is formed is inward, A liquid crystal cell can also be manufactured by a method in which a substrate of one of the other substrates is joined and sealed. The thickness of the spacer at this time is preferably 1 to 30 占 퐉, more preferably 2 to 10 占 퐉.

The step of producing a liquid crystal cell by irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer is performed by applying an electric field to the liquid crystal alignment film and the liquid crystal layer by applying a voltage between electrodes provided on the substrate, And irradiating ultraviolet rays while maintaining this electric field. Here, the voltage applied between the electrodes is, for example, 5 to 30 Vp-p, preferably 5 to 20 Vp-p. The dose of ultraviolet rays is, for example, 1 to 60 J, preferably 40 J or less, and more preferably 20 J or less. The lower irradiation dose of ultraviolet rays is preferable because the lowering of the reliability caused by the destruction of the liquid crystal or members constituting the liquid crystal display element can be suppressed and the manufacturing efficiency can be increased by reducing the ultraviolet ray irradiation 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 by this polymer is stored, . When ultraviolet rays are irradiated while a voltage is applied to the liquid crystal alignment film and the liquid crystal layer, the side chains for vertically orienting the liquid crystal and the side chains for orienting the liquid crystal in the side chain and the side chains for the methacryl group, acrylic group, vinyl group, allyl group, coumarin group, styryl group, Reactive side chains of a polyimide precursor having at least one kind of photoreactive side chain containing at least one selected and a polyimide obtained by imidizing the polyimide precursor, And the polymerizable compound reacts with the side chain of the photoreactive side of the liquid crystal display element.

The liquid crystal aligning agent is not only useful as a liquid crystal aligning agent for producing a liquid crystal display element of a vertical alignment type such as a PSA type liquid crystal display or an SC-PVA type liquid crystal display, but also a liquid crystal aligning agent produced by rubbing treatment or photo alignment treatment And can also be preferably used as a liquid crystal alignment film.

Example

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

The polymerizable compound added to the liquid crystal aligning agent has the following structure.

[Chemical Formula 39]

(40)

(41)

(42)

(43)

(44)

[Chemical Formula 45]

RM7 is ADAMANTATE X-DA manufactured by Idemitsu Kosan Co., Ltd.

(46)

RM8 is DCP manufactured by Shin Nakamura Chemical Industry Co.,

(Synthesis of polymerizable compound RM1 (5,5- (biphenyl-4,4'-diyl bis (oxy)) bis (pentane-5,1-diyl) bis (2-methacrylate)

14.9 g (80.0 mmol) of biphenol, 35 g (167.0 mmol) of 5-bromopentyl acetate, 41.5 g (300 mmol) of potassium carbonate and 250 ml of acetone were added to a 500 ml eggplant- And the mixture was reacted while stirring at a temperature of 60 占 폚 for 48 hours. After completion of the reaction, the reaction solution was poured into 600 ml of pure water to obtain 33.6 g of a white solid. The result of measurement of this solid by NMR is shown below. From this result, it was confirmed that this white solid was the compound (RM1-A) shown in the following reaction formula. The yield was 95%.

(47)

To the 1 L flask equipped with a cooling tube was added 250 mL of ethanol, 18.0 g (41 mmol) of the compound (RM1-A) obtained above and 100 mL of a 10% sodium hydroxide aqueous solution to prepare a mixture, For 5 hours with stirring. After completion of the reaction, 500 ml of water and a reaction solution were added to 1000 ml of the beaker, and the mixture was stirred at room temperature for 30 minutes. 80 ml of a 10% HCl aqueous solution was added dropwise thereto and filtrated to obtain 12.2 g of a white solid. The result of measurement of this solid by NMR is shown below. From this result, it was confirmed that the white solid was the compound (RM1-B) represented by the following reaction formula. The yield was 83%.

(48)

The compound obtained in the above (RM1-B) 5.0 g ( 14.0 m㏖) of triethylamine (Et ₃ N) 3.2 g, and a small amount of 2,6-di -tert- butyl -p- cresol with tetra (BHT) Was dissolved in 30 ml of hydrofluoric acid (THF), stirred at room temperature, and a solution prepared by dissolving 3.3 g (32 mmol) of methacryloyl chloride in 20 ml of THF under cooling with a water bath was dropwise added over 15 minutes Respectively. After the dropwise addition, the mixture was stirred for 30 minutes, the water bath was removed, and stirring was continued overnight while returning to room temperature. After completion of the reaction, the reaction solution was poured into 200 ml of pure water and filtered to obtain a white solid. This solid was dissolved in chloroform and hexane (hexane / chloroform = 2/1) was precipitated to obtain 2.6 g of a white solid. The result of measurement of this solid by NMR is shown below. From this result, it was confirmed that this white solid was the polymerizable compound RM1 shown in the following reaction formula. The yield was 38%.

(49)

(Synthesis of polymerizable compound RM4)

(50)

(Wherein Ac represents CH ₃ CO-)

Compound [A] (17.00 g, 79.2 mmol), compound [B] (50.00 g, 239 mmol), potassium carbonate (66.09 g, 239 mmol), N, N'-dimethylform Amide (DMF) (200 g) was added, the mixture was purged with nitrogen, and the mixture was heated and stirred at 100 占 폚. After confirming the completion of the reaction, the reaction solution was poured into distilled water (1.6 L) to precipitate a precipitated solid, which was then filtered and washed with distilled water to obtain crude product.

Next, the obtained crude product was transferred to a reaction vessel, and ethanol (350 g) and a 10 wt% sodium hydroxide aqueous solution (245 g) were added, followed by heating and stirring at 85 캜. After confirming the completion of the reaction, the reaction solution was poured into a 10 wt% hydrochloric acid aqueous solution (500 g) and the precipitated solid was filtered. Washed successively with distilled water, methanol and ethyl acetate, and dried under reduced pressure to obtain 14.53 g (yield: 51%) of compound [C].

Subsequently, the above-obtained compound [C] (14.53 g, 37.6 mmol), triethylamine (5.33 g, 52.6 mmol) and THF (200 g) were introduced into a 1 L four-necked flask, The solution was cooled to below 10 ° C. Thereto, a solution of methacryloyl chloride (6.87 g, 52.6 mmol) in THF (25 g) was added dropwise with caution to exotherm. After the dropwise addition, the reaction solution was returned to 23 DEG C and further stirring was continued. After the completion of the reaction, the reaction solution was poured into distilled water (1.7 L). Ethyl acetate / hexane mixed solvent was added thereto, and the aqueous layer was removed by separating operation. The organic layer was washed three times with 10 wt% aqueous potassium carbonate solution and brine, and then the organic layer was dried with magnesium sulfate, and the solvent was distilled off using a separator to obtain a crude product of the polymerizable compound RM4 . The obtained crude product was washed with 2-propanol / hexane, and the resulting solid was dried under reduced pressure to obtain 13.1 g (yield: 66%) of a polymerizable compound RM4.

≪ Preparation of liquid crystal aligning agent &

The abbreviations used in the preparation of the following liquid crystal aligning agent are as follows.

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

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

DBA: 3,5-diaminobenzoic acid

PCH: 1,3-diamino-4- [4- (4-heptylcyclohexyl) phenoxy] benzene

BEM-S: 2- (methacryloyloxy) ethyl 3,5-diaminobenzoate represented by the following formula

(51)

NMP: N-methyl-2-pyrrolidone

BCS: butyl cellosolve

The conditions for measuring the molecular weight of the polyimide are as follows.

Apparatus: Room temperature gel permeation chromatography (GPC) apparatus (SSC-7200) manufactured by Senshu Scientific Corporation,

Column: Column (KD-803, KD-805) manufactured by Shodex Co.,

Column temperature: 50 ° C

Eluent: 30 mmol / l of lithium bromide · hydrate (LiBr · H ₂ O), 30 mmol / l of phosphoric anhydride crystal (o-phosphoric acid) as an additive, N, N'-dimethylformamide Furan (THF) of 10 ml / l)

Flow rate: 1.0 ml / min

Standard for the production of calibration curve Sample: TSK standard polyethylene oxide (molecular weight about 900,000, 150,000, 100,000, 30,000) manufactured by Toso Corporation and polyethylene glycol (molecular weight about 12,000, 4,000, 1,000) manufactured by Polymer Laboratories.

The imidization rate of the polyimide was measured as follows. 20 mg of the polyimide powder was placed in an NMR sample tube (NMR sampling tube standard? 5 manufactured by Kusano Scientific Co., Ltd.) and 1.0 ml of deuterated dimethyl sulfoxide (DMSO-d ₆ , 0.05% TMS (tetramethylsilane) And completely dissolved by applying ultrasonic waves. This solution was subjected to proton NMR measurement at 500 MHz using an NMR measuring device (JNW-ECA500) manufactured by Nippon Denshoku. The proton derived from the structure in which the imidization rate does not change before and after the imidization is defined as the reference proton and the proton peak integrated value derived from the NH group of the amic acid appearing in the vicinity of 9.5 to 10.0 ppm is used And was obtained by the following formula. In the following formula, x is the proton peak integrated value derived from the NH group of the amic acid, y is the peak integrated value of the reference proton, and? Is the amount of the amic acid in the case where the polyamic acid (imidation rate is 0% NH < / RTI > group.

Imidization ratio (%) = (1 -? X / y) x 100

(Example 1)

BODA (17.01 g, 68.0 mmol), DBA (10.35 g, 68.0 mmol), PCH (19.41 g, 51.0 mmol) and BEM-S (13.48 g, 51.0 mmol) were dissolved in NMP (239.75 g) After reacting at 80 ° C for 5 hours, CBDA (19.67 g, 100.3 mmol) and NMP (79.92 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution. NMP was added to the polyamic acid solution (399 g) to dilute it to 6 mass%, acetic anhydride (43.33 g) and pyridine (134.33 g) were added as an imidization catalyst and reacted at 50 ° C for 3 hours. The reaction solution was poured into methanol (5300 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimide powder (A). The imidization ratio of the polyimide was 60%, the number average molecular weight was 20,000, and the weight average molecular weight was 55,000.

NMP (64.0 g) was added to the obtained polyimide powder (A) (6.0 g), and the mixture was stirred and dissolved at 50 占 폚 for 12 hours. BCS (30.0 g) was added to this solution and stirred at 50 占 폚 for 5 hours to obtain liquid crystal aligning agent (B).

To 10.0 g of the liquid crystal aligning agent (B) was added 0.06 g (10% by mass based on the solid content) of the polymerizable compound RM2 and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (B1).

(Example 2)

To 10.0 g of the liquid crystal aligning agent (B), 0.06 g (10% by mass relative to solid content) of a polymerizable compound RM3 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (B2).

(Example 3)

To 10.0 g of the liquid crystal aligning agent (B), 0.06 g (10% by mass relative to solid content) of a polymerizable compound RM4 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (B3).

(Example 4)

To 10.0 g of the liquid crystal aligning agent (B), 0.06 g (10% by mass relative to solid content) of a polymerizable compound RM5 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (B4).

(Example 5)

To 10.0 g of the liquid crystal aligning agent (B), 0.06 g of the polymerizable compound RM6 (10% by mass based on the solid content) was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (B5).

(Example 6)

0.06 g (10% by mass relative to solid content) of a polymerizable compound RM7 was added to 10.0 g of the liquid crystal aligning agent (B) and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (B6).

(Example 7)

0.06 g (10% by mass relative to solid content) of a polymerizable compound RM8 was added to 10.0 g of the liquid crystal aligning agent (B) and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (B7).

(Comparative Example 1)

To 10.0 g of the liquid crystal aligning agent (B), 0.06 g (10% by mass relative to solid content) of a polymerizable compound RM1 was added and dissolved by stirring at room temperature for 3 hours to prepare a liquid crystal aligning agent (B8).

≪ Production of liquid crystal cell &

(Example 8)

Using the liquid crystal aligning agent (B1) obtained in Example 1, a liquid crystal cell was produced in the following procedure. The liquid crystal aligning agent (B1) obtained in Example 1 was spin-coated on the ITO surface of the ITO electrode substrate on which the ITO electrode pattern having the pixel size of 100 mu m x 300 mu m and the line / space of 5 mu m was formed, And then fired in a hot air circulating oven at 200 캜 for 30 minutes to form a liquid crystal alignment film having a thickness of 100 nm.

The liquid crystal aligning agent B1 was spin-coated on the ITO surface on which the electrode pattern had not been formed and dried on a hot plate at 80 DEG C for 90 seconds and then fired in a hot air circulating oven at 200 DEG C for 30 minutes, A liquid crystal alignment film having a thickness of 100 nm was formed.

A bead spacer of 6 mu m was dispersed on the liquid crystal alignment film of one of the two substrates, and then a sealing agent (XN-1500T manufactured by Kyoritsu Chemical Co., Ltd.) was printed thereon. Subsequently, the side of the other substrate on which the liquid crystal alignment film was formed was set inward, and the resultant substrate was laminated with the above substrate, and then the sealant was cured to prepare a vacant cell. A liquid crystal cell was prepared by injecting liquid crystal MLC-6608 (trade name, manufactured by Merck & Co., Inc.) into the open cell by a low pressure injection method and performing Isotropic treatment (redistribution treatment of liquid crystal by heating) in an oven at 120 캜.

The response speed immediately after the production of the obtained liquid crystal cell was measured by the following method. Thereafter, in a state in which a voltage of 20 Vp-p was applied to the liquid crystal cell, UV rays having passed through a 313 nm band-pass filter were irradiated from the outside of the liquid crystal cell to 20 J. Thereafter, the response speed was again measured, and the response speeds before and after the UV irradiation were compared. Table 2 shows the results of the response speeds immediately after the liquid crystal cell was prepared (indicated as "initial" in the table) and after UV irradiation (indicated as "after UV" in the table).

How to measure the response speed

First, a liquid crystal cell was disposed between a set of polarizers in a measuring apparatus comprising a backlight, a set of polarizers in a crossed Nicol state, and a light amount detector in this order. At this time, the pattern of the ITO electrode in which the line / space was formed was made to have an angle of 45 degrees with respect to Cross-Nicol. Then, a rectangular wave having a voltage of +4 V and a frequency of 1 kHz was applied to the liquid crystal cell, and the change until the luminance observed by the light amount detector was saturated was inputted to the oscilloscope, and the luminance Was set to 0%, a voltage of ± 4 V was applied to set the value of saturation to 100%, and the time required for the luminance to change from 10% to 90% was set as a response speed.

(Example 9)

The same operation as in Example 8 was performed except that the liquid crystal aligning agent (B2) was used in place of the liquid crystal aligning agent (B1), and the response speeds before and after UV irradiation were compared.

(Example 10)

The same operation as in Example 8 was carried out except that the liquid crystal aligning agent (B3) was used instead of the liquid crystal aligning agent (B1), and the response speeds before and after UV irradiation were compared.

(Example 11)

The same operation as in Example 8 was carried out except that the firing temperature was changed from 200 캜 to 140 캜 and the liquid crystal aligning agent (B4) was used in place of the liquid crystal aligning agent (B1), and the response speeds before and after UV irradiation were compared .

(Example 12)

The same operation as in Example 8 was performed except that the firing temperature was changed from 200 占 폚 to 140 占 폚 and the liquid crystal aligning agent (B5) was used instead of the liquid crystal aligning agent (B1), and the response speeds before and after UV irradiation were compared .

(Example 13)

The same operation as in Example 8 was carried out except that the firing temperature was changed from 200 占 폚 to 140 占 폚 and the liquid crystal aligning agent (B6) was used instead of the liquid crystal aligning agent (B1), and the response speeds before and after UV irradiation were compared .

(Example 14)

The same operation as in Example 8 was carried out except that the firing temperature was changed from 200 占 폚 to 140 占 폚 and the liquid crystal aligning agent (B7) was used in place of the liquid crystal aligning agent (B1), and the response speeds before and after UV irradiation were compared .

(Comparative Example 2)

The same operation as in Example 8 was performed except that the liquid crystal aligning agent (B8) was used in place of the liquid crystal aligning agent (B1), and the response speeds before and after UV irradiation were compared.

<Storage stability test>

(Example 15)

Using the liquid crystal aligning agent (B1) obtained in Example 1, the storage stability test of the liquid crystal aligning agent was carried out in the following procedure. The liquid crystal aligning agent (B1) obtained in Example 1 was stored in a freezer maintained at minus 20 캜, and the liquid crystal aligning agent was observed after 24 hours. When the polymerizable compound added to the liquid crystal aligning agent was dissolved, "dissolved" was determined. When the polymerizable compound was precipitated, "precipitation" was determined.

(Example 16)

A storage stability test was carried out by carrying out the same operation as in Example 15 except that the liquid crystal aligning agent (B2) was used in place of the liquid crystal aligning agent (B1).

(Example 17)

A storage stability test was carried out by carrying out the same operations as in Example 15 except that the liquid crystal aligning agent (B3) was used in place of the liquid crystal aligning agent (B1).

(Example 18)

A storage stability test was carried out by carrying out the same operations as in Example 15 except that the liquid crystal aligning agent (B4) was used instead of the liquid crystal aligning agent (B1).

(Example 19)

A storage stability test was carried out by carrying out the same operation as in Example 15 except that the liquid crystal aligning agent (B5) was used in place of the liquid crystal aligning agent (B1).

(Example 20)

A storage stability test was carried out by carrying out the same operation as in Example 15 except that the liquid crystal aligning agent (B6) was used in place of the liquid crystal aligning agent (B1).

(Example 21)

A storage stability test was carried out by carrying out the same operations as in Example 15 except that the liquid crystal aligning agent (B7) was used instead of the liquid crystal aligning agent (B1).

(Comparative Example 3)

A storage stability test was carried out by carrying out the same operation as in Example 15 except that the liquid crystal aligning agent (B8) was used in place of the liquid crystal aligning agent (B1).

As a result, as shown in Table 2, in all of Examples 8 to 14, the response speed was very fast. The polymerizable compound having a mother nucleus represented by the above formula (i-1) to (i-3) which is a specific polymerizable compound and the polymerizable compound having a mother nucleus represented by the above formulas (ii- In Examples 15 to 21 containing the compound, precipitation occurred in Comparative Example 3 containing no other polymerizable compound, although the polymerizable compound did not precipitate even when stored in the freezer.

Therefore, a polymer such as a polyimide having a photoreactive side chain and a polymerizable compound having a mother nucleus represented by the above formulas (i-1) to (i-3) and the above formulas (ii-1) to ) As a liquid crystal aligning agent containing a polymerizable compound having a mother nucleus, it was confirmed that the liquid crystal aligning agent capable of achieving a very high response speed and excellent storage stability.

Further, in the same manner as in Examples 1 to 6 and Comparative Example 1, except that the mass ratio NMP / BCS of NMP and BCS at the time of obtaining the liquid crystal aligning agent (B) was changed to the value shown in the following Table 3, And a liquid crystal aligning agent were prepared. The mixing ratio of the polymerizable compound of each liquid crystal aligning agent is 10% by mass based on the solid content in any polymerizable compound, as described above.

For each of the liquid crystal aligning agents whose solvent composition was changed, the storage stability test was carried out in the same manner as described above. As a result, as shown in Table 3, a polymerizable compound having a mother nucleus represented by the above formulas (i-1) to (i-3) or a polymeric compound having a mother nucleus represented by the above formulas (ii- In the liquid crystal aligning agent containing the polymerizable compound having the polymerizable compound, the polymerizable compound was not precipitated even if it was kept frozen in any solvent composition, but precipitation occurred in the liquid crystal aligning agent containing the other polymerizable compound RM1.

Claims (14)

A polyimide having a photoreactive side chain containing a side chain that vertically aligns the liquid crystal and at least one selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, At least one polymer selected from polyimides obtained by imidizing the polyimide precursor,
(Ii) at least one kind of core selected from the following formulas (i-1) to (i-3), and a group capable of photopolymerization or photo-crosslinking at one or more ends, A polymerizable compound bonded to the mother nucleus,
A liquid crystal aligning agent characterized by having a solvent.

The method according to claim 1,
Wherein the polymerizable compound is selected from the following formulas.

(Wherein, R ³¹ represents a single bond or -R ³⁵ O-, R ³⁵ is an alkylene group having a carbon number of 1 to 10 straight-chain, R ³² represents a single bond or -OR ³⁶ - represented by, R ³⁶ is straight An alkylene group having 1 to 10 carbon atoms in the chain, and R ³³ and R ³⁴ each independently represent a hydrogen atom or a methyl group) A polyimide having a photoreactive side chain containing a side chain that vertically aligns the liquid crystal and at least one selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, At least one polymer selected from polyimides obtained by imidizing the polyimide precursor,
, At least one kind of core selected from the following formulas (ii-1) and (ii-3), and a group capable of photopolymerizing or photo-crosslinking at one or more ends, wherein the photopolymerizable or photo- The polymerizable compound,
A liquid crystal aligning agent characterized by having a solvent.

The method of claim 3,
Wherein the polymerizable compound is selected from the following formulas.

(Wherein R ⁴¹ is a single bond or -R ⁴⁵ O-, R ⁴⁵ is an alkylene group having 1 to 10 carbon atoms in the linear chain, R ⁴² is a single bond or -OR ⁴⁶ -, and R ⁴⁶ is a direct bond An alkylene group having 1 to 10 carbon atoms in the chain, and R ⁴³ and R ⁴⁴ are each independently a hydrogen atom or a methyl group) A polyimide having a photoreactive side chain containing a side chain that vertically aligns the liquid crystal and at least one selected from a methacryl group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, At least one polymer selected from polyimides obtained by imidizing the polyimide precursor,
A polymerizable compound represented by the following formula,
A liquid crystal aligning agent characterized by having a solvent.

(Wherein R ⁴¹ is a single bond or -R ⁴⁵ O-, R ⁴⁵ is an alkylene group having 1 to 10 carbon atoms in the linear chain, R ⁴² is a single bond or -OR ⁴⁶ -, and R ⁴⁶ is a direct bond An alkylene group having 1 to 10 carbon atoms in the chain, and R ⁴³ and R ⁴⁴ are each independently a hydrogen atom or a methyl group) The method according to claim 1,
Wherein the side chain of the photoreactive group contains a group selected from the following formula (I).

(Wherein R &lt; ¹¹ &gt; is H or a methyl group) The method according to claim 1,
Wherein the photopolymerization or photo-crosslinking group is selected from the following formula (II).

(Wherein R ¹² is H or an alkyl group having 1 to 4 carbon atoms, Z ¹ is a bivalent aromatic ring or heterocyclic ring which may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms, and Z ² is a monovalent aromatic ring or heterocyclic ring which may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms) The method of claim 3,
Wherein the side chain of the photoreactive group contains a group selected from the following formula (I).

(Wherein R &lt; ¹¹ &gt; is H or a methyl group) The method of claim 3,
Wherein the photopolymerization or photo-crosslinking group is selected from the following formula (II).

(Wherein R ¹² is H or an alkyl group having 1 to 4 carbon atoms, Z ¹ is a bivalent aromatic ring or heterocyclic ring which may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms, and Z ² is a monovalent aromatic ring or heterocyclic ring which may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms) 6. The method of claim 5,
Wherein the side chain of the photoreactive group contains a group selected from the following formula (I).

(Wherein R &lt; ¹¹ &gt; is H or a methyl group) delete A liquid crystal alignment film obtained by applying the liquid crystal aligning agent according to any one of claims 1 to 10 to a substrate and firing the liquid crystal alignment film. A liquid crystal alignment layer according to any one of claims 1 to 10, which is applied to a substrate and fired, is brought into contact with a liquid crystal alignment film to form a liquid crystal layer, and ultraviolet rays are irradiated while applying voltage to the liquid crystal layer A liquid crystal display element comprising a liquid crystal cell. A liquid crystal alignment layer according to any one of claims 1 to 10, which is applied to a substrate and fired, is brought into contact with a liquid crystal alignment film to form a liquid crystal layer. While applying a voltage to the liquid crystal layer, Wherein the liquid crystal display element is manufactured by a method comprising the steps of: