WO2023219075A1

WO2023219075A1 - Method for manufacturing substrate equipped with weak anchoring alignment film, and method for manufacturing liquid crystal display element

Info

Publication number: WO2023219075A1
Application number: PCT/JP2023/017398
Authority: WO
Inventors: 一世三宅
Original assignee: 日産化学株式会社
Priority date: 2022-05-10
Filing date: 2023-05-09
Publication date: 2023-11-16
Also published as: TW202403414A

Abstract

Provided is a method for manufacturing a substrate equipped with a weak anchoring alignment film, used to manufacture a liquid crystal cell having liquid crystal and a weak anchoring alignment film, wherein the method for manufacturing a substrate equipped with a weak anchoring alignment film includes: a step for coating a substrate with a weak anchoring liquid crystal alignment agent including a polymer α which is a component that exhibits weak anchoring properties, and a polymer β which is a component that does not exhibit weak anchoring properties and exhibits uniaxial alignment regulating force by an alignment treatment, and providing a thin film on the substrate; and a step for performing an alignment treatment on the thin film.

Description

Method for manufacturing a substrate with weak anchoring alignment film and method for manufacturing a liquid crystal display element

The present invention provides a method for manufacturing a substrate with a weak anchoring alignment film, which allows manufacturing an organic film exhibiting weak anchoring properties (weak anchoring film) using a method that is inexpensive and does not involve complicated steps, and The present invention relates to a liquid crystal display element that achieves higher brightness and lower voltage driving.

In recent years, liquid crystal display elements have been widely used in displays for mobile phones, computers, televisions, and the like. Liquid crystal display elements have characteristics such as being thin, lightweight, and low power consumption, and are expected to be applied to further content such as VR (Virtual Reality) and ultra-high-definition displays in the future. Various display methods have been proposed for liquid crystal displays, including the TN (Twisted Nematic) method, the IPS (In-Plane Switching) method, and the VA (Vertical Alignment) method. A film (liquid crystal alignment film) that induces a desired alignment state is used.

In particular, for products equipped with touch panels such as tablet PCs, smartphones, and smart TVs, the IPS method is preferred because the display is less distorted even when touched, and in recent years FFS (Fringe Field Switching ) liquid crystal display elements using the method and liquid crystal alignment technology using the optical alignment method are used.

However, the FFS method has problems in that the manufacturing cost of the substrate is higher than that in the IPS method, and a unique display defect called Vcom shift occurs. Furthermore, compared to the rubbing alignment method, the photo-alignment method has the advantage of being easier to adapt to device enlargement and greatly improving display characteristics, but there are some theoretical issues (when using photodegradable materials, Display defects, and if the photoisomerization type is used, there may be burn-in due to insufficient alignment power, etc.). In order to solve these problems, liquid crystal display element manufacturers and liquid crystal alignment film manufacturers are currently making various efforts.

In recent years, at the contact interface between the liquid crystal and the base material in a liquid crystal cell, a compatible interface (completely wet liquid-liquid crystal interface) is formed between the polymer and the liquid crystal, which has no alignment regulating force in the in-plane direction. It has been discovered that it is possible to create a "zero-plane anchoring" state, and a liquid crystal switching device that has no switching threshold and has orientation memory has been reported (see Patent Document 1).

A weak anchoring IPS method that applies weak anchoring technology has been proposed. This can improve the contrast ratio and realize significantly lower voltage driving than the conventional IPS method (see Patent Document 2).

The weak anchoring IPS method uses a liquid crystal alignment film that has strong anchoring energy on one substrate, and a process that does not have anchoring energy on the other substrate (which is equipped with an electrode that generates a transverse electric field). It is made using organic thin films.

In recent years, a weak anchoring IPS method using a method of directly providing a thick polymer brush on a substrate has been proposed (see Patent Document 3).

A weak anchoring IPS method has been proposed in which a liquid crystal alignment film capable of generating photoradicals and a compound capable of radical polymerization are used to generate weak anchoring by irradiating UV in the liquid crystal and causing a radical reaction (Patent Document (see 4). With this technology, in addition to improving contrast ratio and significantly lower voltage drive using a method that can be mass-produced, we have achieved faster response and reduced burn-in.

Japanese Patent Application Publication No. 2006-84536 Patent No. 4053530 Japanese Patent Application Publication No. 2013-231757 International Publication No. 2019/004433 pamphlet

The method of directly providing a dense polymer brush on a substrate (Patent Document 3) requires a surface treatment step to provide reaction points on the substrate and a step of growing polymer from the reaction points on the substrate surface, which complicates the process, and requires advanced technology. Since it requires deoxidizing conditions and the environment must be strictly controlled, it is technically difficult and impractical from the perspective of mass production. Therefore, a method has been proposed in which a weakly anchored IPS display element is obtained by applying a bottlebrush polymer having an anchoring site onto a substrate.However, when manufacturing a bottlebrush polymer, a macromonomer having a polymerization initiation site is used. However, in addition, since both are produced using living radical polymerization, there is a problem in that it is difficult to supply them in large quantities. In addition, bottle brush polymers have poor solvent selectivity and low solubility in commonly used N-methyl-2-pyrrolidone (NMP) and γ-butyrolactone (GBL), making them difficult to use in commonly used coating processes. Because of its structure, it has poor sealing and adhesion to substrates, so it is necessary to consider a method that can solve these problems.

In the method of weakly anchoring using a photoradical polymerization reaction and a radically polymerizable compound (Patent Document 4), the polymerizable additive is volatilized under high vacuum conditions during liquid crystal injection, and ultraviolet rays are removed after the liquid crystal element is fabricated. It is thought that there are problems such as an adverse effect on the liquid crystal composition during the irradiation process.

In the weak anchoring IPS method, it is necessary to form a weak anchoring alignment film on one of the two base materials constituting the liquid crystal cell, so the response speed when the voltage is turned off becomes slow. This is a problem specific to weak anchoring IPS systems. If the response speed becomes slow, it is conceivable that the display quality of video images will deteriorate and the applications to which it can be applied will be greatly limited, so increasing the response speed can be said to be the biggest challenge from the perspective of putting weak anchoring IPS into practical use.

If such technical issues can be solved, it will be possible for panel manufacturers to easily produce weakly anchored IPS liquid crystal display elements with high yields, which have advantages such as battery power savings and improved image quality.

The present invention was made to solve the above-mentioned problems, and can solve the trade-off between weak anchoring property and high-speed response when voltage is turned off, which has been a trade-off in weak anchoring IPS. . That is, an object of the present invention is to provide a substrate with a weak anchoring alignment film that does not generate a pretilt angle and can simultaneously realize low-voltage driving and high-speed response when the voltage is turned off, and a liquid crystal display device using the same. There is.

In order to solve the above-mentioned problems, the present inventors conducted intensive studies and found that the above-mentioned problems could be solved, and completed the present invention having the following gist.
That is, the present invention includes the following.

[1] A method for manufacturing a substrate with a weak anchoring alignment film used for manufacturing a liquid crystal cell having a liquid crystal and a weak anchoring alignment film, the method comprising:
A weakly anchoring liquid crystal aligning agent containing a polymer α, which is a component that exhibits weak anchoring properties, and a polymer β, which is a component that does not exhibit weak anchoring properties and exhibits a uniaxial alignment regulating force through alignment treatment. coating on a substrate and providing a thin film on the substrate;
a step of subjecting the thin film to an orientation treatment;
A method for manufacturing a substrate with a weak anchoring alignment film, comprising:
[2] The method for producing a substrate with a weak anchoring alignment film according to [1], wherein the polymer β is a polymer that has a horizontal alignment regulating force when subjected to an alignment treatment.
[3] The method for manufacturing a substrate with a weak anchoring alignment film according to [1] or [2], wherein the weak anchoring alignment film is a liquid crystal alignment film subjected to a uniaxial alignment treatment.
[4] The weak anchor according to any one of [1] to [3], wherein the polymer α contains at least one selected from the group consisting of polymer A, polymer B, and polymer C below. A method for manufacturing a substrate with a ring alignment film.
Polymer A: A block copolymer having a block segment (A) that is compatible with the liquid crystal and a block segment (B) that is not compatible with the liquid crystal or becomes insolubilized in the liquid crystal upon firing.
Polymer B: a graft copolymer having a backbone polymer and a branch polymer bonded to the backbone polymer as a side chain of the backbone polymer, wherein the branch polymer is compatible with the liquid crystal and the backbone polymer is not compatible with the liquid crystal or becomes incompatible with the liquid crystal upon firing.
Polymer C: A polymer that has a polymer unit that is compatible with the liquid crystal and reacts with the polymer β when heated.
[5] The block segment (A) in the polymer A is a compound represented by the following formula (2), a compound represented by the following formula (3), a compound represented by the following formula (4), and Containing as a constituent component at least one selected from the group consisting of compounds represented by the following formula (5),
The block segment (B) in the polymer A contains a compound represented by the following formula (6) as a constituent component,
The method for manufacturing a substrate with a weak anchoring alignment film according to [4].

(In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond. , R ₁ represents an alkyl group having 1 to 20 carbon atoms which may have a bonding group inserted therein, and n is an integer of 1 to 2. When n is 2, the two X and R ₁ are each the same. (It may be different or it may be different.)

(In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms which may have a bonding group inserted therein. , T represents an organic group represented by the following formula (3-T), and n is an integer of 1 to 2. When n is 2, the two Ts may be the same or different. (However, when n is 2, S represents a saturated hydrocarbon group having 1 to 6 carbon atoms that may have a bonding group inserted.)

(In formula (3-T), * indicates a bonding site. X is a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si(R ₁ )(R ₂ )- (R ₁ and R ₂ each independently represent an alkyl group bonded to Si.), -Si(R ₃ )(R ₄ )-O-(R ₃ and R ₄ each independently bond to Si. represents an alkyl group), and -N(R ₅ )-(R ₅ represents a hydrogen atom or an alkyl group bonded to N), and Cy is a 6- to 20-membered non-ring group. (Represents an aromatic cyclic group.)

(In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R ₁ represents an aliphatic hydrocarbon group having a linear or branched structure having 1 to 10 carbon atoms, and 3 Each of the three X's independently represents a hydrogen atom or the following formula (4-X).However, at least one of the three X's represents the formula (4-X).)

(In formula (4-X), Y represents a single bond, -O-, -S-, or -N(R)-(R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms bonded to N. ), and * indicates a bonding site. R ₂ , R ₃ , and R ₄ each independently represent an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group that may have a substituent. )

(In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and R ₁ to R ₃ are each independently a single bond or the number of carbon atoms into which a bonding group may be inserted. represents an alkylene group of 1 to 6, Ar represents an aromatic hydrocarbon group that may have a substituent, and X ₁ and X ₂ are each independently a hydrogen atom, or R ₁ X ₁ and R ₂ X ₂ and the carbon atoms bonded to R ₁ X ₁ and R ₂ X ₂ may form a ring together. The total number of carbon atoms in R ₁ X ₁ , R ₂ X ₂ and R ₃ is 1 or more.)

(In formula (6), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and n is an integer of 1 to 2. Z represents a group represented by the following formula (6-Z). (If n is 2, the two Zs may be the same or different.)

(In formula (6-Z), L is a trialkoxysilyl group, an isocyanate group, a blocked isocyanate group, an epoxy group, an oxetane group, a vinyl group, an allyl group, an oxazoline group, an amino group, a protected amino group, an aniline group, a protected aniline group) group, hydroxy group, protected hydroxy group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxy group, maleimide group, N-hydroxysuccinimide ester group, bonding group Aromatic hydrocarbon group having 5 to 18 carbon atoms which may have a bonding group inserted therein, an aromatic heterocyclic group having 5 to 18 carbon atoms which may have a bonding group inserted therein, a cinnamic acid group, a cinnamic acid aromatic ester group , a cinnamic acid alkyl ester group, a cinnamyl group, a phenylbenzoate group, an azobenzene group, an N-benzylideneaniline group, a stilbene group, and a tolan group. J is a single bond or has 1 to 1 carbon atoms. 6 represents an aliphatic hydrocarbon group.When K is bonded to an aromatic hydrocarbon group, it represents a linking group selected from a single bond, an ether bond, an ester bond, an amide bond, a urea bond, a urethane bond, and a thioether bond. In other cases, it indicates a single bond. * represents a binding site. m is an integer from 1 to 3. When m is 2 or 3, multiple K and L may be the same. (However, if J is a single bond, m is 1.)
[6] The method for producing a substrate with a weak anchoring alignment film according to [4] or [5], wherein the branch polymer in the polymer B is derived from a macromonomer represented by the following formula (7).

(In formula (7), P represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and Q represents a polymerizable monomer containing at least one of the compounds represented by the following formulas (2) to (5). (n is an integer of 1 to 2. When n is 2, the two Qs may be the same or different.)

(In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and R ₁ to R ₃ are each independently a single bond or the number of carbon atoms into which a bonding group may be inserted. represents an alkylene group of 1 to 6, Ar represents an aromatic hydrocarbon group that may have a substituent, and X ₁ and X ₂ are each independently a hydrogen atom, or R ₁ X ₁ and R ₂ X ₂ and the carbon atoms bonded to R ₁ X ₁ and R ₂ X ₂ may form a ring together. The total number of carbon atoms in R ₁ X ₁ , R ₂ X ₂ and R ₃ is 1 or more.)
[7] The substrate with a weak anchoring alignment film according to any one of [4] to [6], wherein the backbone polymer in the polymer B contains a compound represented by the following formula (6) as a constituent component. Production method.

(In formula (6-Z), L is a trialkoxysilyl group, an isocyanate group, a blocked isocyanate group, an epoxy group, an oxetane group, a vinyl group, an allyl group, an oxazoline group, an amino group, a protected amino group, an aniline group, a protected aniline group) group, hydroxy group, protected hydroxy group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxy group, maleimide group, N-hydroxysuccinimide ester group, bonding group Aromatic hydrocarbon group having 5 to 18 carbon atoms which may have a bonding group inserted therein, an aromatic heterocyclic group having 5 to 18 carbon atoms which may have a bonding group inserted therein, a cinnamic acid group, a cinnamic acid aromatic ester group , a cinnamic acid alkyl ester group, a cinnamyl group, a phenylbenzoate group, an azobenzene group, an N-benzylideneaniline group, a stilbene group, and a tolan group. J is a single bond or has 1 to 1 carbon atoms. 6 represents an aliphatic hydrocarbon group.When K is bonded to an aromatic hydrocarbon group, it represents a linking group selected from a single bond, an ether bond, an ester bond, an amide bond, a urea bond, a urethane bond, and a thioether bond. In other cases, it indicates a single bond. * represents a binding site. m is an integer from 1 to 3. When m is 2 or 3, multiple K and L may be the same. (However, if J is a single bond, m is 1.)
[8] The method for producing a substrate with a weak anchoring alignment film according to any one of [4] to [7], wherein the polymer C is a polymer represented by the following formula (8).

(In formula (8), A is an n-valent organic compound having a molecular weight of 500 or less and having a group that reacts with the polymer β upon heating, selected from the following formulas (8-A-1) to (8-A-16). represents a group.
Q is a divalent polymer unit that is compatible with the liquid crystal and contains as a constituent at least one kind selected from the group consisting of compounds represented by the following formulas (2) to (5).
R is a monovalent organic group selected from the following formulas (8-R-1) to (8-R-11) and having a molecular weight of 500 or less that does not react with the polymer β upon heating.
n is an integer from 1 to 2. When n is 2, the two Q's and R's may be the same or different. )

(In formulas (8-A-1) to (8-A-16), R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and R ₃ and R ₄ each independently represents a single bond or a linear or branched alkylene group having 1 to 12 carbon atoms, and X represents an oxygen atom or a sulfur atom. * represents a bonding site.)

(In formulas (8-R-1) to (8-R-11), R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and R ₃ and Each R ₄ independently represents a single bond or a linear or branched alkylene group having 1 to 12 carbon atoms. * represents a bonding site.)

(In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and R ₁ to R ₃ are each independently a single bond or the number of carbon atoms into which a bonding group may be inserted. represents an alkylene group of 1 to 6, Ar represents an aromatic hydrocarbon group that may have a substituent, and X ₁ and X ₂ are each independently a hydrogen atom, or R ₁ X ₁ and R ₂ X ₂ and the carbon atoms bonded to R ₁ X ₁ and R ₂ X ₂ may form a ring together. The total number of carbon atoms in R ₁ X ₁ , R ₂ X ₂ and R ₃ is 1 or more.)
[9] M in the formula (2) is any of the structures represented below,
M in the formula (3) is any of the structures represented below,
M in the formula (4) is any of the structures represented below,
M in the formula (5) is any of the structures represented below,
The method for manufacturing a substrate with a weak anchoring alignment film according to any one of [5], [6], and [8].

(In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and X, Y, and Z each independently represent an oxygen atom or a sulfur atom. *, * ¹ and * ² represent bonding sites, and either one of * ¹ and * ² may be replaced with a hydrogen atom or a straight chain or branched alkyl group having 1 to 12 carbon atoms. n is Represents an integer from 1 to 5.)
[10] Any of [1] to [9], wherein the polymer β is at least one kind of polymer selected from the group consisting of polyimide, polyamic acid, polyamic acid ester, polyamide, polyurea, and poly(meth)acrylate. A method for manufacturing a substrate with a weakly anchoring alignment film as described in .
[11] A polyimide precursor in which the polymer β is obtained by polymerizing a diamine component and a tetracarboxylic acid derivative component containing at least one compound selected from the group consisting of tetracarboxylic dianhydride and derivatives thereof. The method for producing a substrate with a weak anchoring alignment film according to any one of [1] to [10], wherein the substrate is a polymer selected from the group consisting of polyimide, which is an imidized product of the polyimide precursor.
[12] The method for producing a substrate with a weak anchoring alignment film according to [11], wherein the tetracarboxylic acid derivative component includes a tetracarboxylic dianhydride represented by the following formula (9).

(In formula (9), X represents a structure selected from the group consisting of the following formulas (X-1) to (X-17) and (XR-1) to (XR-2).)

(In formulas (X-1) to (X-17), R ₁ to R ₄ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, Alkynyl group having 2 to 6 carbon atoms, monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, alkoxy group having 1 to 6 carbon atoms, alkoxyalkyl group having 2 to 6 carbon atoms, 2 to 6 carbon atoms represents an alkyloxycarbonyl group or a phenyl group. R ₅ and R ₆ each independently represent a hydrogen atom or a methyl group.
In formulas (XR-1) to (XR-2), j and k are integers of 0 or 1, and A ₁ and A ₂ each independently represent a single bond, -O-, -CO-, -COO-, represents a phenylene group, a sulfonyl group, or an amide group. The plurality of _A2 's may be the same or different.
*1 is a bond bonded to one acid anhydride group, and *2 is a bond bonded to the other acid anhydride group. )
[13] The method for producing a substrate with a weak anchoring alignment film according to [12], wherein the formula (X-1) is selected from the group consisting of the following formulas (X1-1) to (X1-6).

(In formulas (X1-1) to (X1-6), *1 is a bond that is bonded to one acid anhydride group, and *2 is a bond that is bonded to the other acid anhydride group.)
[14] The method for producing a substrate with a weak anchoring alignment film according to any one of [11] to [13], wherein the diamine component includes a diamine represented by the following formula (10).

(In formula (10), Ar ₁ and Ar _1' each independently represent a benzene ring, a biphenyl structure, or a naphthalene ring, and one or more of the benzene ring, the biphenyl structure, or the naphthalene ring may be substituted with a monovalent group. L ₁ and L _1' each independently represent a single bond, -O-, -C(=O)-, or -O-C(= O)-.A represents -CH ₂ -, an alkylene group having 2 to 12 carbon atoms, or between the carbon-carbon bond of the alkylene group, -O-, -C(=O)-O-, Represents a divalent organic group in which at least one of the following groups is inserted:
[15] The method for producing a substrate with a weakly anchoring alignment film according to any one of [4] to [14], wherein the polymer C is a polymer obtained by living polymerization or chain transfer polymerization.
[16] A method for manufacturing a liquid crystal display element, comprising the step of manufacturing a substrate with a weak anchoring alignment film by the method for manufacturing a substrate with a weak anchoring alignment film according to any one of [1] to [15].

According to the present invention, it is possible to solve the trade-off between weak anchoring property and high-speed response when the voltage is turned off, which has been a trade-off in weak anchoring IPS. Furthermore, by using the materials and methods of the present invention, we provide a weak anchoring alignment film that does not generate a pretilt angle and can simultaneously achieve low voltage drive and high-speed response when the voltage is turned off, and a liquid crystal display element using the same. can do.

1 is a schematic cross-sectional view showing an example of a horizontal electric field liquid crystal display element of the present invention. FIG. 3 is a schematic cross-sectional view showing another example of the horizontal electric field liquid crystal display element of the present invention.

(weak anchoring)
In the present invention, "weak anchoring" refers to having a force that regulates the alignment of liquid crystal molecules in the azimuthal or polar direction with respect to the substrate, but with anchoring strength (i.e., maintaining the position of the liquid crystal molecules). Alternatively, even if the orientation of liquid crystal molecules changes, there is no interfacial elastic energy to restore the original state, or even if there is, it is weaker than the intermolecular force between liquid crystals, and in the weak anchoring of the present invention. refers to the case where the azimuthal anchoring strength (A ₂ ) is smaller than 10 ⁻⁵ [J/m ² ]. As described in JP-A No. 2013-231757, a polymer capable of forming a completely wet state with the liquid crystal is provided at the base material interface, and when the liquid crystal comes into contact with the polymer, a polymer-liquid crystal mixed layer is formed, resulting in weak anchoring. The condition is known to occur.

(Weak anchoring alignment film)
In the present invention, the term "weakly anchoring alignment film" refers to a film that forms a weakly anchored state upon contact with liquid crystal, and is not limited to solid films, but also includes liquid films that cover solid surfaces.
Note that the "weak anchoring alignment film" is also referred to as "weak anchoring liquid crystal alignment film".

(Strong anchoring, strong anchoring alignment film)
In the present invention, "strong anchoring" refers to the ability to regulate the alignment of liquid crystal molecules in a uniaxial alignment and maintain the alignment of the liquid crystal even when energy is applied from the outside, or the ability to maintain the alignment of the liquid crystal even if the alignment of the liquid crystal molecules changes. In the strong anchoring of the present invention, it refers to the case where the azimuthal anchoring strength (A ₂ ) is greater than 10 ⁻⁴ [J/m ² ]. . Furthermore, the term "strongly anchoring alignment film" refers to a film that forms a strong anchoring state when it comes into contact with liquid crystal, and is not limited to solid films, but also includes liquid films that cover solid surfaces.
Note that the "strong anchoring alignment film" is also referred to as "strong anchoring liquid crystal alignment film."

(Weak anchoring liquid crystal display element)
A weak anchoring liquid crystal display element can be produced by applying the above-defined weak anchoring alignment film and strong anchoring alignment film to a substrate with electrodes, respectively, and pasting them together in a pair. In weak anchoring liquid crystal display elements, the azimuthal anchoring strength of one liquid crystal alignment film is extremely small, so a weak electric field or external field energy can induce alignment changes in the liquid crystal, and liquid crystal molecules in areas that normally do not move can also be aligned. This makes it possible to drive liquid crystal molecules on electrodes with weak electric field strength, especially in display elements using comb-shaped electrodes such as IPS and FFS. Compared to a liquid crystal display element in which both films are composed of strong anchoring alignment films, higher transmittance and lower driving voltage can be achieved.

The azimuthal anchoring strength is an index representing the strength of interfacial elastic energy between liquid crystal molecules and a liquid crystal alignment film in the azimuthal direction. As a method for calculating the azimuthal anchoring strength, a torque balance method, a strong electric field method, a geometry method (external field application method), a Frederiks transfer method, etc. are used.

(polymer alloy)
One embodiment of the "polymer alloy" in the present invention is a polymer (hereinafter sometimes referred to as "polymer α") that is a component that exhibits weak anchoring properties and is contained in a weakly anchoring liquid crystal aligning agent. It is a polymer alloy made of a polymer (hereinafter sometimes referred to as "polymer β") which is a component that does not exhibit weak anchoring properties and exhibits uniaxial alignment regulating force through alignment treatment. Weak anchoring liquid crystal alignment agents are used to form a film for aligning liquid crystals used in liquid crystal display elements, that is, a liquid crystal alignment film.

The polymer alloy of the present invention is characterized in that it is obtained by mixing at least one of each of polymer α and polymer β. In a preferred embodiment, the polymer α exhibits excellent weak anchoring properties (also referred to as a “weak anchoring component”), while the polymer β does not exhibit weak anchoring properties and can be easily stabilized by orientation treatment. Expresses uniaxial alignment regulating force. In addition, by selecting an appropriate polymer β, we can provide the weak anchoring alignment film with excellent film hardness and excellent seal adhesion strength by adhering to the substrate, cross-linking between polymers, and cross-linking with the sealing component. Moreover, a weakly anchoring liquid crystal aligning agent having excellent solvent selectivity and coating properties can be obtained.

International Publication No. 2019/004433 pamphlet proposes a weakly anchored liquid crystal display element that uses a graft copolymer (called a polymer brush) with a high density of branch polymers using living polymerization. The polymer brush is synthesized using a method of extending branch polymers (grafting from method), and needs to be synthesized using living polymerization. In addition, attempts have been made to improve the adhesion between the substrate and the polymer by introducing groups into the branch polymer that contribute to improved adhesion to the substrate, but if the amount introduced is large, the weak anchoring property may be impaired. Also, since the density of the branched polymer is very high, it is thought that solvation with the solvent will be difficult to occur, and the affinity for relatively high boiling point and relatively polar solvents such as NMP and γ-butyrolactone will be impaired. It is possible that

In the applicant's verification, a weakly anchoring liquid crystal aligning agent using a block copolymer produced by living polymerization rather than a polymer brush was also investigated, and an application has been filed (Patent Application No. 2021-96448, WO202/2260048). However, the solvent selectivity and adhesion strength of the polymer were found to be low, which is thought to be a common problem with precisely synthesized polymers, similar to polymer brushes. The results are described in the Examples.

The method for manufacturing a substrate with a weak anchoring alignment film of the present invention is used for manufacturing a liquid crystal cell having a liquid crystal and a weak anchoring alignment film.
The method for manufacturing a substrate with a weak anchoring alignment film of the present invention includes the following steps.
・Process of applying a weak anchoring liquid crystal alignment agent containing polymer α and polymer β onto a substrate to form a thin film on the substrate ・Process of applying alignment treatment to the thin film

The substrate to which the weak anchoring liquid crystal aligning agent is applied is not particularly limited as long as it is a highly transparent substrate, but a substrate on which a transparent electrode for driving the liquid crystal is formed is preferable. A specific example will be described later.

The method of applying the weak anchoring liquid crystal aligning agent onto the substrate is not particularly limited, and examples thereof include spin coating, printing, inkjet, spraying, and roll coating, but from the viewpoint of productivity, Industrially, transfer printing is preferred.
After applying the weak anchoring liquid crystal aligning agent onto the substrate, drying and/or baking may be performed. Drying and firing conditions are not particularly limited, and include, for example, the conditions described below.

Although the thickness of the thin film can be selected as necessary, it is preferably 5 nm or more, more preferably 10 nm or more, since this improves the reliability of the liquid crystal display element. Further, it is preferable that the thickness of the thin film is preferably 300 nm or less, more preferably 150 nm or less, since the power consumption of the liquid crystal display element does not become extremely large.

The orientation treatment applied to the thin film is preferably uniaxial orientation treatment.
Examples of methods for performing the uniaxial alignment treatment include a photoalignment method, an oblique evaporation method, rubbing, and a uniaxial alignment treatment using a magnetic field.
When performing alignment treatment by rubbing in one direction, for example, while rotating a rubbing roller around which a rubbing cloth is wound, the substrate is moved so that the rubbing cloth and the film come into contact with each other. When using a photo-alignment method, the alignment treatment can be performed by irradiating the entire surface of the film with polarized UV of a specific wavelength and heating if necessary.
In the case of a substrate on which comb-teeth electrodes are formed, the direction is selected depending on the electrical properties of the liquid crystal, but when using a liquid crystal with positive dielectric anisotropy, the rubbing direction is the direction in which the comb-teeth electrodes extend. It is preferable that the direction is approximately the same as that of .

In one embodiment of the method for manufacturing a substrate with a weakly anchoring alignment film of the present invention, an organic film made of a polymer alloy obtained by mixing polymer α and polymer β is formed on a substrate, and then an alignment treatment is performed on the organic film. (preferably uniaxial alignment treatment). The polymer α preferably contains at least one selected from the group consisting of polymer A, polymer B, and polymer C. The polymer β is preferably at least one type of polymer selected from the group consisting of polyimide, polyamic acid, polyamic acid ester, polyamide, polyurea, and poly(meth)acrylate. As will be specifically exemplified in the examples below, polymer β is a polymer that exhibits excellent uniaxial alignment regulating force through rubbing alignment treatment and photo alignment treatment, and is a polymer that exhibits excellent uniaxial alignment regulating force through rubbing alignment treatment and photo alignment treatment, and is a polymer that exhibits an excellent uniaxial alignment regulating force through rubbing alignment treatment and photo alignment treatment. By subjecting the ring alignment film to alignment treatment (preferably uniaxial alignment treatment), the response speed when the voltage is turned off can be increased while maintaining sufficient weak anchoring properties. Furthermore, by selecting an appropriate polymer β, the weak anchoring alignment film can be given excellent film hardness and excellent seal adhesion strength by adhering to the substrate, cross-linking between polymers, and cross-linking with the sealing component. Moreover, a weakly anchoring liquid crystal aligning agent having excellent solvent selectivity and coating properties can be obtained.

(Polymer A)
One embodiment of the polymer A is a copolymer having a block segment (A) that is compatible with the liquid crystal and a block segment (B) that is not compatible with the liquid crystal or becomes insolubilized in the liquid crystal upon firing.
Polymer A is, for example, a linear copolymer consisting of two or more types of block segments obtained by living polymerization, at least one block segment consisting of a block segment (A) soluble in liquid crystal, and at least one block segment consists of a block segment (B) that does not dissolve in the liquid crystal or becomes insoluble in the liquid crystal upon firing.

The block segment (A) in polymer A is a compound represented by the following formula (2), a compound represented by the following formula (3), a compound represented by the following formula (4), and the following formula (5). It is preferable that at least one kind selected from the group consisting of the compounds represented by: is included as a constituent component.
It is preferable that the block segment (B) in the polymer A contains a compound represented by the following formula (6) as a constituent component.
The polymer A is a polymer in which the block segment (A) of the polymer A is synthesized from at least one selected from the group consisting of compounds represented by the following formulas (2) to (5), and It is preferable that the block segment (B) is a polymer synthesized from a compound represented by the following formula (6).

The present applicant has proposed a radically polymerizable compound contained in a liquid crystal composition that can stably produce a weakly anchoring horizontal electric field liquid crystal display element without generating a pretilt angle, and which is a radical polymerizable compound that contributes to the occurrence of weak anchoring. We have discovered and applied for a compound represented by the following formula (2), a compound represented by the formula (3), a compound represented by the formula (4), and a compound represented by the formula (5) as chemical compounds. (Japanese Patent Application No. 2020-134149, Japanese Patent Application No. 2020-163212, Japanese Patent Application No. 2021-041196, WO2022/030602, WO2022/071286, WO2022/196565, WO2019/004433. These applications and publications are hereby incorporated by reference. The contents of the publications are incorporated herein to the same extent as if expressly set forth in their entirety.)

In addition, the applicant has discovered that the weakly anchoring liquid crystal aligning agent containing Polymer A can produce weakly anchoring films more easily and stably than conventional methods, and that the weakly anchoring liquid crystal aligning agent containing Polymer A can be used to produce weakly anchored films more easily and stably than conventional methods. Horizontal electric field liquid crystal that can simultaneously achieve stable low-voltage drive without the occurrence of corners and high-speed response when voltage is OFF, reduce burn-in, and achieve both high backlight transmittance and low-voltage drive in low-temperature environments. The company has filed an application to provide a display element (Japanese Patent Application No. 2021-96448 and WO202/2260048. By being cited here, the contents of this application and publication are to the same extent as if they were fully disclosed. (incorporated herein).

The copolymer may have three or more types of block segments.
The copolymer is preferably a copolymer in which the main chain extends linearly without branching.

(In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond. , R ₁ represents an alkyl group having 1 to 20 carbon atoms which may have a bonding group inserted therein, and n is an integer of 1 to 2. When n is 2, the two X and R 1 are each the same. (It may be different, or it may be different.)
Examples of the bonding group in the alkyl group having 1 to 20 carbon atoms into which a bonding group may be inserted include ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si(R ₁₁ )( R ₁₂ )-(R ₁₁ and R ₁₂ each independently represent an alkyl group bonded to Si.), -Si(R ₁₃ )(R ₁₄ )-O-(R ₁₃ and R ₁₄ each independently represent an alkyl group bonded to Si. (represents an alkyl group bonded to Si), -N(R ₁₅ )-(R ₁₅ represents a hydrogen atom or an alkyl group bonded to N). Examples of the alkyl group for R ₁₁ to R ₁₅ include alkyl groups having 1 to 6 carbon atoms.

The saturated hydrocarbon group in S in formula (3) refers to an n+1-valent group formed by removing n+1 hydrogen atoms from a saturated hydrocarbon (n is the same integer as n in formula (3)). be). When n is 1, the saturated hydrocarbon group is an alkylene group.
In S in formula (3), a saturated hydrocarbon group having 1 to 6 carbon atoms into which a bonding group is inserted is a saturated hydrocarbon group having a bonding group inserted between carbon atoms in a saturated hydrocarbon group having 2 to 6 carbon atoms. or an n+1-valent group in which a bonding group is inserted between a saturated hydrocarbon group having 1 to 6 carbon atoms and an atom bonded thereto (for example, a carbon atom).
Examples of the bonding group for S in formula (3) include a carbon-carbon unsaturated bond, an ether bond (-O-), an ester bond (-COO- or -OCO-), an amide bond (-CONH- or - Examples include NHCO-). Examples of carbon-carbon unsaturated bonds include carbon-carbon double bonds, but a saturated hydrocarbon group having 1 to 6 carbon atoms into which a carbon-carbon double bond is inserted has no It is preferable to have a carbon-carbon double bond inside.
When n is 1, examples of the alkylene group having 1 to 6 carbon atoms into which a bonding group may be inserted include alkylene groups having 1 to 6 carbon atoms, oxyalkylene groups having 1 to 6 carbon atoms, etc. .
The alkylene group having 1 to 6 carbon atoms may be a straight chain alkylene group, a branched alkylene group, or a cyclic alkylene group.

R ₁ and R ₂ of -Si(R ₁ )(R ₂ )- in X of formula (3-T) are each independently an alkyl group bonded to Si, for example, an alkyl group having 1 to 6 carbon atoms. It is the basis.
R ₃ and R ₄ of -Si(R ₃ )(R ₄ )-O- in X of formula (3-T) are each independently an alkyl group bonded to Si, for example, a carbon number of 1 to 6. is an alkyl group.
R ₅ of -N(R ₅ )- in X of formula (3-T) is a hydrogen atom or an alkyl group bonded to N. The alkyl group is, for example, an alkyl group having 1 to 6 carbon atoms.

In formula (3-T), Cy is a 6- to 20-membered non-aromatic cyclic group, preferably an 8- to 18-membered non-aromatic cyclic group. Note that Cy may be a 12- to 20-membered non-aromatic cyclic group. In formula (3-T), X is bonded to an atom constituting a ring in Cy.
Examples of the atoms constituting the ring in the non-aromatic cyclic group include carbon atoms, oxygen atoms, nitrogen atoms, and silicon atoms.
The bond between the atoms constituting the ring may be a single bond, a double bond, or a triple bond, but a single bond is preferable.
Examples of the ring in the non-aromatic cyclic group include cyclic alkanes, cyclic ethers, and cyclic siloxanes. Examples of the cyclic ether include crown ether. For example, in 12-crown-4, the atoms constituting the ring are carbon atoms and oxygen atoms, and the number of members is 12.
The ring may be monocyclic or polycyclic. Examples of the number of rings in the polycycle include 2 to 4.
For example, the following three ways are included in how the rings are bonded to each other in a polycyclic ring.
・One-atom sharing: For example, spiro ring compounds ・Two-atom sharing: When two rings share two atoms, such as in decalin ・Bridging structure: When two rings share three atoms, such as in norbornane Cases in which more than one atom is considered to be in common In the case of a polycyclic ring, the number of ring members is determined by the number of atoms that make up the ring. For example, norbornane is a 7-membered ring.
A halogen atom or an alkyl group having 1 to 6 carbon atoms may be bonded to the atoms constituting the ring instead of a hydrogen atom. Examples of the halogen atom include a fluorine atom and a chlorine atom.

The aliphatic hydrocarbon group in R ₁ in formula (4) has 1 to 10 carbon atoms, may have 1 to 8 carbon atoms, may have 1 to 6 carbon atoms, or may have 1 to 6 carbon atoms. It may be 1 to 4.

The alkyl group having 1 to 6 carbon atoms in R ₂ , R ₃ , and R ₄ in formula (4-X) may be, for example, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having 1 to 5 carbon atoms. 4 may be an alkyl group. These alkyl groups may have a linear structure or a branched structure.

The aromatic hydrocarbon groups represented by R ₂ , R ₃ , and R ₄ in formula (4-X) may be unsubstituted, or the hydrogen atoms may be substituted with a substituent.
Examples of the substituent of the aromatic hydrocarbon group which may have a substituent include a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, and a halogen having 1 to 4 carbon atoms. Examples include alkyl groups, halogenated alkoxy groups having 1 to 4 carbon atoms, and the like. The halogenation in the halogenated alkyl group and the halogenated alkoxy group may be complete halogenation or partial halogenation. Examples of the halogen atom include a fluorine atom and a chlorine atom.
Examples of the aromatic hydrocarbon group which may have a substituent include a phenyl group and a naphthyl group.
The number of substituents in the aromatic hydrocarbon group is not particularly limited.

In formula (4), formula (4-X) is one or more, and may be one, two, or three.
In formula (4), the three X's are each independent. Therefore, in formula (4), when there are two or more formulas (4-X), the two or more formulas (4-X) may have the same structure or different structures.

In formula (4-X), at least one of R ₂ , R ₃ and R ₄ may be an aromatic hydrocarbon group which may have a substituent. Therefore, in formula (4-X), one of R ₂ , R ₃ , and R ₄ may be an aromatic hydrocarbon group that may have a substituent, and R ₂ , R ₃ , and Two of R ₄ may be an aromatic hydrocarbon group which may have a substituent, or three of R ₂ , R ₃ and R ₄ may be an aromatic hydrocarbon group which may have a substituent. It may be a base.

In R ₁ to R ₃ in formula (5), an alkylene group having 1 to 6 carbon atoms into which a bonding group is inserted is an alkylene group having a bonding group inserted between carbon atoms in the alkylene group having 1 to 6 carbon atoms. or a divalent group in which a bonding group is inserted between an alkylene group having 1 to 6 carbon atoms and a carbon atom bonded thereto.
Examples of the bonding group include a carbon-carbon unsaturated bond, an ether bond (-O-), an ester bond (-COO- or -OCO-), and an amide bond (-CONH- or -NHCO-). Examples of unsaturated bonds include carbon-carbon double bonds, but alkylene groups with 1 to 6 carbon atoms into which a bonding group is inserted have a carbon-carbon double bond inside, not at the end. It is preferable to have a bond.
Examples of the alkylene group having 1 to 6 carbon atoms into which a bonding group may be inserted include alkylene groups having 1 to 6 carbon atoms, oxyalkylene groups having 1 to 6 carbon atoms, and the like. The oxygen atom in the oxyalkylene group having 1 to 6 carbon atoms is bonded to, for example, the carbon atom bonded to M, R ₁ , R ₂ , and R ₃ in formula (5).
The alkylene group having 1 to 6 carbon atoms may be a straight chain alkylene group, a branched alkylene group, or a cyclic alkylene group.

Examples of the aromatic hydrocarbon group which may have a substituent in X ₁ and X ₂ of formula (5) include a phenyl group, a naphthyl group, and the like which may have a substituent.
Examples of the substituent include a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogenated alkyl group having 1 to 4 carbon atoms, a halogenated alkoxy group having 1 to 4 carbon atoms, etc. can be mentioned. The halogenation in the halogenated alkyl group and the halogenated alkoxy group may be complete halogenation or partial halogenation. Examples of the halogen atom include a fluorine atom and a chlorine atom.

Examples of R ₁ in formula (5) include a single bond and an alkylene group having 1 to 6 carbon atoms. More specifically, the alkylene group having 1 to 6 carbon atoms includes a straight chain alkylene group having 1 to 6 carbon atoms.
Examples of R ₂ in formula (5) include a single bond and an alkylene group having 1 to 6 carbon atoms. More specifically, the alkylene group having 1 to 6 carbon atoms includes a straight chain alkylene group having 1 to 6 carbon atoms.
Examples of R ₃ in formula (5) include a single bond and an alkylene group having 1 to 6 carbon atoms. More specifically, the alkylene group having 1 to 6 carbon atoms includes a straight chain alkylene group having 1 to 6 carbon atoms.
Examples of X ₁ in formula (5) include a hydrogen atom and a phenyl group.
Examples of X ₂ in formula (5) include a hydrogen atom and a phenyl group.
Ar in formula (5) includes, for example, a phenyl group.

The total carbon number of R ₁ X ₁ , R ₂ X ₂ and R ₃ in formula (5) is not particularly limited as long as it is 1 or more, but may be 2 or more.
Further, the total carbon number of R ₁ , R ₂ , and R ₃ in formula (5) may be, for example, 18 or less, 15 or less, or 10 or less. .
Further, when X ₁ and X ₂ in formula (5) are hydrogen atoms, the total number of carbon atoms in R ₁ , R ₂ , and R ₃ is not particularly limited as long as it is 1 or more, but even if it is 2 or more, good.
In addition, when at least one of X ₁ and X ₂ in formula (5) is an aromatic hydrocarbon group which may have a substituent, the total carbon number of R ₁ , R ₂ , and R ₃ is 0. It may be.

In formula (5), the ring formed by R ₁ X ₁ , R ₂ X ₂ _, and the carbon atoms bonded to R ₁ X ₁ and R ₂ Examples include hydrocarbon rings having 3 to 13 carbon atoms, which may be optional. The binding group is as described above.

By using the structure of the above compound, it is easy to achieve high-speed response when the voltage is turned off, reduced burn-in, high backlight transmittance in a low-temperature environment, and low-voltage driving.

The block segment (A) is mainly swollen by the liquid crystal in a thin film state and plays the role of forming a weak anchoring film. Since the physical properties of the weak anchoring film vary greatly depending on the molecular weight of the block segment (A), optimization of the molecular weight is not necessary but is important. From the viewpoint of forming a good weak anchoring film, the molecular weight of the block segment (A) is preferably 1,000 to 100,000, more preferably 3,000 to 50,000. Note that this molecular weight is a number average molecular weight (Mn) in terms of polystyrene measured by gel permeation chromatography (GPC). Further, the molecular weight distribution PDI (Mw/Mn), which is expressed as the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) in terms of polystyrene measured by GPC, is preferably 3.0 or less, and more preferably is 2.0 or less.

The block segment (A) may be a single polymer of the above compounds, or a combination of multiple compounds may be used. When used in combination, random copolymerization or block copolymerization may be used. When combining with a compound species that is compatible with liquid crystal, the ratio is not particularly limited regardless of the combination method. When combined with a compound species that becomes insolubilized in liquid crystal as described below, from the viewpoint of maintaining properties, the preferred combination ratio of compound species that becomes insolubilized in liquid crystal is 30 mol% or less, more preferably 20 mol% or less, but there are no limitations. do not. It is preferable to use these combination methods, the types of compounds to be combined, and the combination ratio within a range that allows desired physical properties, display characteristics, electrical characteristics, etc. to be obtained.

The block segment (B) contributes to the stability of the film in a thin film state.

Block segment (B) is preferably a trialkoxysilyl group, an isocyanate group, a blocked isocyanate group, an epoxy group, an oxetane group, a vinyl group, an allyl group, an oxazoline group, an amino group, a protected amino group, an aniline group, a protected aniline group. , hydroxy group, protected hydroxy group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxy group, maleimide group, N-hydroxysuccinimide ester group, bonding group Aromatic hydrocarbon group having 5 to 18 carbon atoms which may be inserted, an aromatic heterocyclic group having 5 to 18 carbon atoms which may have a bonding group inserted, cinnamic acid group, cinnamic acid aromatic ester group, It has a side chain structure having at least one functional group selected from the group consisting of a cinnamic acid alkyl ester group, a cinnamyl group, a phenylbenzoate group, an azobenzene group, an N-benzylideneaniline group, a stilbene group, and a tolan group. Specific examples of the bonding group include the specific examples of the bonding group listed in the explanation of formula (2).
In that case, the block segment (B) contains, for example, a polymerizable compound having the above functional group and a polymerizable group having a polymerizable unsaturated hydrocarbon group as a constituent component.

An example of the polymerizable compound used to form the block segment (B) is represented by the following formula (6).

(In formula (6-Z), L is a trialkoxysilyl group, an isocyanate group, a blocked isocyanate group, an epoxy group, an oxetane group, a vinyl group, an allyl group, an oxazoline group, an amino group, a protected amino group, an aniline group, a protected aniline group) group, hydroxy group, protected hydroxy group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxy group, maleimide group, N-hydroxysuccinimide ester group, bonding group Aromatic hydrocarbon group having 5 to 18 carbon atoms which may have a bonding group inserted therein, an aromatic heterocyclic group having 5 to 18 carbon atoms which may have a bonding group inserted therein, a cinnamic acid group, a cinnamic acid aromatic ester group , a cinnamic acid alkyl ester group, a cinnamyl group, a phenylbenzoate group, an azobenzene group, an N-benzylideneaniline group, a stilbene group, and a tolan group. J is a single bond or has 1 to 1 carbon atoms. 6 represents an aliphatic hydrocarbon group.When K is bonded to an aromatic hydrocarbon group, it represents a linking group selected from a single bond, an ether bond, an ester bond, an amide bond, a urea bond, a urethane bond, and a thioether bond. In other cases, it indicates a single bond. * represents a binding site. m is an integer from 1 to 3. When m is 2 or 3, multiple K and L may be the same. (However, if J is a single bond, m is 1.)

The block segment (B) has a side chain structure that is not compatible with the liquid crystal or becomes incompatible with the liquid crystal upon firing. Compounds that are incompatible with the liquid crystal used to form the block segment (B) include highly polar compounds and compounds with a rigid structure. Examples of the compound species that are no longer compatible with the thermosetting compound species include thermosetting compound species.

An example of the polymerizable compound used to form the block segment (B) is a compound having a polymerizable group having a polymerizable unsaturated hydrocarbon group and a highly polar structure.
The above highly polar structure preferably has the following structure. However, it is not limited to these.

(X and Y each independently represent an oxygen atom or a sulfur atom. R ₁ and R ₂ each independently represent a single bond or an alkylene group having 1 to 18 carbon atoms. R ₃ represents an alkylene group having 1 to 18 carbon atoms. Represents an alkyl group. One of _{A 1} , A ₂ and A ₃ represents N, and the remaining two represent CH. One of A ₄ and A ₅ represents N, and the remaining one represents CH. (* represents the binding site, and n represents an integer from 0 to 4.)

An example of the polymerizable compound used to form the block segment (B) is a compound having a polymerizable group having a polymerizable unsaturated hydrocarbon group and a rigid structure.
The above rigid structure preferably has the following structure. However, it is not limited to these.

(X, Y, and Z each independently represent an oxygen atom or a sulfur atom. R ₁ and R ₂ each independently represent a single bond or an alkylene group having 1 to 18 carbon atoms. R ₃ represents a carbon number 1 ~18 represents an alkyl group. * represents a bonding site, n represents an integer from 1 to 5.)

An example of the polymerizable compound used to form the block segment (B) is a compound having a polymerizable group having a polymerizable unsaturated hydrocarbon group and a thermosetting structure.
The above thermosetting structure preferably has the following structure. However, it is not limited to these.

(X, Y and Z each independently represent an oxygen atom or a sulfur atom. R ₁ , R ₂ and R ₃ each independently represent an alkyl group having 1 to 18 carbon atoms. R ₄ and R ₅ are Each independently represents a single bond or an alkylene group having 1 to 18 carbon atoms. * represents a bonding site, and n represents an integer from 0 to 5.)

In the present invention, the following structures are preferred as the polymerizable group having a polymerizable unsaturated hydrocarbon group.

(In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and X, Y, and Z each independently represent an oxygen atom or a sulfur atom. *, * ¹ and * ² represent bonding sites, and either one of * ¹ and * ² may be replaced with a hydrogen atom or a straight chain or branched alkyl group having 1 to 12 carbon atoms. n is Represents an integer from 1 to 5.)

The block segment (B) is mainly responsible for stabilizing the thin film state and does not significantly affect the physical properties of the weak anchoring film. It is sufficient that the block segment (B) complements the stability of the membrane, and the optimal molecular weight that can complement the stability of the membrane is not particularly limited because it varies depending on the type of compound used. Further, depending on the type of compound used, advantages can be obtained in solvent selectivity and coating properties, so it is preferable to control the type of compound constituting the block segment (B) and its molecular weight depending on the use and purpose.

For the block segment (B), the above polymerizable compounds may be used alone, or a plurality of compounds may be used in combination. As mentioned above, the block segment (B) is a block segment that only contributes to the stability of the membrane, and does not significantly contribute to the weak anchoring properties. Therefore, as long as the stabilization of the membrane is complemented, the type of compound to be combined and the method of combination are Not particularly limited.

One embodiment of the polymer A is characterized in that it is a copolymer having a block segment (A) that is compatible with the liquid crystal and a block segment (B) that is insoluble or insoluble in the liquid crystal, but the number of blocks is not limited. First, a configuration having a plurality of block segments, such as (A)-(B)-(A), for example, may be used, and the number and combination of block segments are not particularly limited. It is also possible to introduce block segments that impart electrical properties. On the other hand, from the viewpoint of ease of synthesis, the number of block segments is preferably about 2 to 4, and from the viewpoint of membrane stability, the terminal block segment of the polymer is preferably block segment (B).

As mentioned above, the block segment (A) that is compatible with the liquid crystal controls weak anchoring properties, and the molecular weight of the block segment (A) greatly affects the properties. The molecular weight ratio is not limited.

Polymer A can be obtained, for example, by living polymerization. Living polymerization is a polymerization reaction in which side reactions such as chain transfer reactions and termination reactions are not accompanied during the polymerization reaction, and it is possible to obtain a polymer with a narrow molecular weight distribution and a highly controlled structure. For example, one method is to suppress the deactivation of the active site by introducing a stable covalent species called a dormant species into the polymerization active site, thereby preventing the occurrence of side reactions such as chain transfer reactions and termination reactions. Living polymerizations include those using radicals, cations, and anions as active species, and it is important to select one depending on the structure and properties of the polymerizable compound used.
When obtaining the block polymer that is Polymer A, the polymerization method does not need to be particularly limited, but cationic polymerization and anionic polymerization often use alkali metals, metal complexes, and halogen compounds to generate active species. In liquid crystal displays, the incorporation of metal residues and halogen compounds can cause burn-in and display defects, so it is preferable to use radical polymerization that uses as few metals and halogen compounds as possible. Examples of living radical polymerization include living radical polymerization (NMP) using nitroxide as a dormant species, atom transfer radical polymerization (ATRP) using a metal complex, and reversible addition/elimination chain transfer polymerization (RAFT) using a sulfur compound as a dormant. Polymerization), living radical polymerization (TERP) using an organic tellurium compound, etc., and reversible transfer catalytic polymerization (RTCP) using an alkyl iodide compound as a dormant species and using a phosphorus compound, alcohol, etc. as a catalyst, etc. are preferred. Examples of the polymerization method include living radical polymerization such as NMP, RTCP, and RAFT polymerization, and NMP or RAFT polymerization is particularly preferred.

When using NMP, examples of the polymerization initiator include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, 1,1 Examples include '-bis(tert-butylperoxy)cyclohexane and hydrogen peroxide. The proportion of the polymerization initiator used is usually 0.000001 to 0.1 part by mole, preferably 0.00001 to 0.01 part by mole, per 1 part by mole of the monomer used. Examples of the nitroxide include compounds represented by the following formulas (N-1) to (N-12). The proportion of nitroxide used is usually 0.000001 to 0.1 part by mole, preferably 0.00001 to 0.01 part by mole, per 1 part by mole of the monomer used. The reaction temperature in the above polymerization is preferably 20 to 200°C, more preferably 40 to 150°C, and the reaction time is preferably 1 to 168 hours, more preferably 8 to 72 hours.

When using RTCP, examples of the polymerization initiator used include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, 1,1 Examples include '-bis(tert-butylperoxy)cyclohexane and hydrogen peroxide. The proportion of the polymerization initiator used is usually 0.000001 to 0.1 part by mole, preferably 0.00001 to 0.01 part by mole, per 1 part by mole of the monomer used.
Examples of the iodide catalyst include compounds represented by the following formulas (P-1) to (P-7). The proportion of the iodide catalyst used is usually 0.000001 to 0.1 part by mole, preferably 0.00001 to 0.01 part by mole, per 1 part by mole of the monomer used. Furthermore, examples of the hydride catalyst include compounds represented by the following formulas (O-1) to (O-6). The proportion of the hydride catalyst used is 0.000001 to 0.1 part by mole, preferably 0.00001 to 0.01 part by mole, per 1 part by mole of the monomer used. Usually, the reaction temperature in the above polymerization is preferably 20 to 200°C, more preferably 40 to 150°C, and the reaction time is preferably 1 to 168 hours, more preferably 8 to 72 hours.

When using RAFT polymerization, examples of the polymerization initiator used include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, 1, Examples include 1'-bis(tert-butylperoxy)cyclohexane and hydrogen peroxide. The proportion of the polymerization initiator used is usually 0.000001 to 0.1 part by mole, preferably 0.00001 to 0.01 part by mole, per 1 part by mole of the monomer used. As the chain transfer agent (RAFT agent), trithiocarbonate, dithiobenzoate, dithiocarbamate, and xanthate are preferable, and specific examples include compounds represented by the following formulas (R-1) to (R-24). can be mentioned. The proportion of the chain transfer agent used is usually 0.000001 to 0.1 part by mole, preferably 0.00001 to 0.01 part by mole, per 1 part by mole of the monomer used. The reaction temperature in the above polymerization is preferably 20 to 200°C, more preferably 40 to 150°C, and the reaction time is preferably 1 to 168 hours, more preferably 8 to 72 hours.

In the formula, Me represents a methyl group.

Living radical properties are expressed in RAFT polymerization because most of the living chains are in the dormant type (dormant type), and there are compounds that can reversibly inactivate the growing radical species. This is because a fast equilibrium exists between the chains.

By using RAFT polymerization, it is possible to control polymer terminals, advanced molecular weight control, and molecular weight distribution control.

In order to precisely synthesize a functional polymer using RAFT polymerization, it is necessary to select an appropriate chain transfer agent in consideration of the reactivity of the monomer.

In RAFT polymerization, polymer terminals can be controlled by thermally and chemically modifying the RAFT terminals present at the growing terminals. In the case of thermal modification, the terminal can be modified into an unsaturated hydrocarbon group by heating at a temperature higher than the temperature at which the RAFT agent used is thermally decomposed. In addition, in the case of chemical modification, the terminal can be modified into a thiol bond by bringing it into contact with a primary amine, secondary amine, etc., accompanied by aminolysis. Furthermore, it is possible to provide a new block segment at the end by bringing it into contact with a new monomer and a radical generator.

In RAFT polymerization, molecular weight control is possible by using the following formula (eq1). Specifically, the number average molecular weight (Mn) changes linearly with the ratio of the molar concentration of the monomer to the molar concentration of the chain transfer agent, making it possible to control the molecular weight.

(In the above formula (eq1), Mn _(theor) represents the molecular weight of the polymer, [Monomer] ₀ represents the molar concentration of the monomer, [CTA] ₀ represents the molar concentration of the chain transfer agent, and M _monomer represents the molar concentration of the monomer. represents the molecular weight of the chain transfer agent, conv. represents the polymerization conversion rate, and _MCTA represents the molecular weight of the chain transfer agent.)

In addition, when the copolymer obtained by the above polymerization is dissolved in the reaction solution, the reaction solution may be used as it is for preparing the liquid crystal aligning agent, or the copolymer contained in the reaction solution may be isolated. Then, it may be used for preparing a liquid crystal aligning agent.

The organic solvent used in the synthesis of the copolymer (polymer A) may be any solvent as long as it does not chemically react with the compound species constituting the copolymer and does not scavenge radicals. For example, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, N-methylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1, 3-dimethyl-2-imidazolidinone, N-methyl-ε-caprolactam, N,N-diethylacetamide, N,N-dipropylacetamide, 3-methoxy-N,N-dimethylpropanamide, N,N-diethyl Propionamide, dimethyl sulfoxide, tetramethyl urea, pyridine, dimethyl sulfone, hexamethyl phosphoramide, γ-butyrolactone, isopropyl alcohol, methoxymethyl pentanol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl Isopropyl ketone, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether (butyl cellosolve), Propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, Dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, Tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, 1,4 -Dioxane, n-hexane, n-pentane, n-octane, cyclohexane, 2-ethyl-1-hexanol, benzene, xylene, toluene, ethylbenzene, isopropylbenzene, tert-butylbenzene, tetrahydrofuran, diethyl ether, cyclohexanone, ethylene Carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate , methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl -2-pentanone, 3-methoxy-N,N-dimethylpropanamide, 3-ethoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, propyl pyruvate, butyl pyruvate, pyruvin Pentyl acetoacetate, hexyl pyruvate, 2-ethylhexyl pyruvate, methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, butyl acetoacetate, pentyl acetoacetate, hexyl acetoacetate, 2-ethylhexyl acetoacetate, methyl levulinate, levulin Ethyl acid, propyl levulinate, butyl levulinate, pentyl levulinate, hexyl levulinate, 2-ethylhexyl levulinate, dimethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl phthalate, dimethyl maleate, Diethyl malonate, diethyl succinate, diethyl glutarate, diethyl adipate, diethyl phthalate, diethyl maleate, dipropyl malonate, dipropyl succinate, dipropyl glutarate, dipropyl adipate, dipropyl phthalate, dipropyl maleate, malonic acid Dibutyl, dibutyl succinate, dibutyl glutarate, dibutyl adipate, dibutyl phthalate, dibutyl maleate, dipentyl malonate, dipentyl succinate, dipentyl glutarate, dipentyl adipate, dipentyl phthalate, dipentyl maleate, dihexyl malonate, Dihexyl succinate, dihexyl glutarate, dihexyl adipate, dihexyl phthalate, dihexyl maleate, di-2-ethylhexyl malonate, 2-ethylhexyl succinate, 2-ethylhexyl glutarate, 2-ethylhexyl adipate, phthalate Examples include 2-ethylhexyl acid and 2-ethylhexyl maleate (hereinafter also referred to as "specific organic solvent"). These organic solvents may be used alone or in combination.

(Polymer B)
Polymer B is a graft copolymer having branch polymers that are compatible with liquid crystals and trunk polymers that are incompatible with liquid crystals or that become incompatible with liquid crystals upon firing. Note that the graft copolymer does not dissolve in the liquid crystal depending on the backbone polymer, or becomes insoluble in the liquid crystal upon baking.
The branch polymer is attached to the trunk polymer as a side chain of the trunk polymer.

The present applicant has proposed that a weak anchoring liquid crystal aligning agent containing polymer B is a weak anchoring liquid crystal aligning agent that can be easily manufactured, has good coating properties, and has good adhesion to a seal, We have discovered that this is a weakly anchoring liquid crystal aligning agent that does not generate a pretilt angle and can provide a weakly anchoring liquid crystal aligning film that simultaneously achieves low voltage drive and high-speed response when voltage is turned off, and has filed a patent application. 2021-156886, WO2023/048278. By reference herein, the contents of this application and publication are incorporated herein to the same extent as if expressly set forth in their entirety.)

Graft copolymer is a general term for polymers with a branched structure, and refers to a polymer that simultaneously has a polymer corresponding to a "trunk" and a polymer corresponding to a "branch" bonded to the trunk as a side chain of the trunk. In one embodiment of the liquid crystal aligning agent of the present invention, a graft copolymer is used as the polymer B, but the graft copolymer is composed of a branch polymer that is compatible with the liquid crystal, and a branch polymer that is not compatible with the liquid crystal, or a liquid crystal that is formed by baking. and a backbone polymer that becomes incompatible with the polymer. In other words, the branch polymer that is compatible with the liquid crystal dissolves in the liquid crystal and swells, contributing to the formation of a weak anchoring state, while the graft copolymer does not dissolve in the liquid crystal due to the trunk polymer, or becomes insolubilized in the liquid crystal by baking. To obtain a weakly anchored liquid crystal display element with excellent film hardness and seal adhesion strength by preventing elution of the graft copolymer into the liquid crystal, fixing it to the substrate, crosslinking the polymers with each other, and crosslinking with the sealing component. I can do it.

The structure of the branch polymer that is compatible with the liquid crystal is not particularly limited as long as it is soluble in the liquid crystal, but for example, the branch polymer can be derived from a macromonomer represented by the following formula (7).

(In formula (7), P represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and Q represents a monomer containing at least one of the compounds represented by formulas (2) to (5) above. It is a structure obtained by polymerization, and n is an integer of 1 to 2. When n is 2, the two Qs may be the same or different.)

The monomer used in the synthesis of the branched polymer may be a single component, or a combination of multiple monomers may be used. Further, other monomers capable of radical polymerization reaction, which will be described below, may be used in combination.

In Polymer B, the branched polymers are largely involved in the expression of weak anchoring properties. Optimization of the molecular weight is important because the physical properties of the weak anchoring film change depending on the molecular weight of the branch polymer. From the viewpoint of forming a good weak anchoring film, the preferred number average molecular weight of the branched polymer is 1,000 to 100,000, more preferably 3,000 to 50,000, and the weight average molecular weight (Mw) and number The molecular weight distribution (PDI) expressed as a ratio to the average molecular weight (Mn) is preferably 3.0 or less, more preferably 2.0 or less. Note that when the graft copolymer is synthesized by a grafting through method using a macromonomer, the molecular weight here corresponds to the molecular weight of the macromonomer.

The structure in which the terminal end of the branched polymer is removed (for example, the structure of Q in formula (7)) may be a single polymer structure using only one type of monomer represented by the above formulas (2) to (5), or a structure in which multiple monomers are used. A copolymer structure consisting of a combination of monomers may also be used. When a plurality of monomers are combined, random copolymerization or block copolymerization may be used. When the monomers represented by the above formulas (2) to (5) are combined, the ratio is not particularly limited regardless of the method of combination. When combined with a compound species that insolubilizes liquid crystals as described below, the preferred combination ratio of monomers that insolubilize liquid crystals is 30 mol% or less, more preferably 20 mol% or less, from the viewpoint of maintaining properties, but there is no limitation. . These synthesis methods, monomers to be combined, and combination ratios are preferably used within a range that allows desired physical properties, display characteristics, electrical characteristics, etc. to be obtained.

The backbone polymer may contain, for example, a compound represented by the above formula (6) as a constituent component.

The macromonomer represented by formula (7), which is the raw material for forming the branch polymer of the graft copolymer that is polymer B, can be obtained, for example, by a combination of living polymerization, chain transfer polymerization, and polymer terminal modification reaction. . Furthermore, it has been reported that a polymer having a radically polymerizable unsaturated bond in the terminal group can be obtained by continuous bulk polymerization at a high temperature of 200° C. or higher (Toagosei Research Annual Report TREND 2002 No. 5).
When obtaining a macromonomer that is a raw material for a graft copolymer, there is no need to particularly limit the polymerization method, but cationic polymerization and anionic polymerization may use alkali metals, metal complexes, or halogen compounds to generate active species. In liquid crystal displays, the contamination of metal residues and halogen compounds can cause burn-in and display defects, so it is preferable to use radical polymerization that uses as few metals and halogen compounds as possible. Examples of living radical polymerization include nitroxide-mediated radical polymerization (NMP) using nitroxide as a dormant species, atom transfer radical polymerization (ATRP) using a metal complex, and reversible addition/fragmentation chain transfer (RAFT) using a sulfur compound as a dormant. ) polymerization, living radical polymerization (TERP) using an organic tellurium compound, etc., reversible transfer catalytic polymerization (RTCP) using an alkyl iodide compound as a dormant species, and using a phosphorus compound, alcohol, etc. as a catalyst, etc. are preferred. Examples of the polymerization method include living radical polymerization such as NMP, RTCP, and RAFT polymerization, and NMP or RAFT polymerization is particularly preferred.

The main synthesis methods for graft copolymers include the Grafting-to method, in which a branch polymer is directly introduced into a trunk polymer, and the Grafting-from method, in which a monomer is polymerized from a macroinitiator (a trunk polymer having a polymerization active site) to extend a branch polymer. The synthesis method is not limited, as any method can be used.

The method for producing the graft copolymer is not particularly limited, and any commonly used industrial method can be used. Specifically, it can be produced by radical polymerization, cationic polymerization, or anionic polymerization using the above-mentioned monomers. Among these, radical polymerization is particularly preferred from the viewpoint of ease of reaction control.

As the polymerization initiator for radical polymerization, known compounds such as radical polymerization initiators (radical thermal polymerization initiators, radical photopolymerization initiators) and reversible addition-fragmentation chain transfer (RAFT) polymerization reagents may be used. I can do it.

A radical thermal polymerization initiator is a compound that generates radicals when heated above the decomposition temperature. Such radical thermal polymerization initiators include, for example, ketone peroxides (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), diacyl peroxides (acetyl peroxide, benzoyl peroxide, etc.), hydroperoxides (peroxide Hydrogen, tert-butyl hydroperoxide, cumene hydroperoxide, etc.), dialkyl peroxides (di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc.), peroxyketals (dibutyl peroxycyclohexane) etc.), alkyl peroxy esters (peroxyneodecanoic acid tert-butyl ester, peroxypivalic acid tert-butyl ester, peroxy 2-ethylcyclohexanoic acid tert-amyl ester, etc.), persulfates (potassium persulfate, , sodium persulfate, ammonium persulfate, etc.), azo compounds (azobisisobutyronitrile, 2,2'-di(2-hydroxyethyl)azobisisobutyronitrile, etc.), and the like. The radical thermal polymerization initiators may be used alone or in combination of two or more.

The radical photopolymerization initiator is not particularly limited as long as it is a compound that initiates radical polymerization by light irradiation. Such radical photopolymerization initiators include benzophenone, Michler's ketone, 4,4'-bis(diethylamino)benzophenone, xanthone, thioxanthone, isopropylxanthone, 2,4-diethylthioxanthone, 2-ethylanthraquinone, acetophenone, 2-hydroxy -2-Methylpropiophenone, 2-hydroxy-2-methyl-4'-isopropylpropiophenone, 1-hydroxycyclohexylphenyl ketone, isopropylbenzoin ether, isobutylbenzoin ether, 2,2-diethoxyacetophenone, 2,2 -dimethoxy-2-phenylacetophenone, camphorquinone, benzanthrone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-( 4-morpholinophenyl)-1-butanone, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 4,4'-di(tert-butylperoxycarbonyl)benzophenone, 3,4,4'-tri( tert-butylperoxycarbonyl)benzophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-(4'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(3' , 4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2 -(2'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4'-pentyloxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 4- [p-N,N-di(ethoxycarbonylmethyl)]-2,6-di(trichloromethyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(2'-chlorophenyl)-s- Triazine, 1,3-bis(trichloromethyl)-5-(4'-methoxyphenyl)-s-triazine, 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylaminostyryl)benzothiazole, 2-mercaptobenzothiazole, 3,3'-carbonylbis(7-diethylaminocoumarin), 2-(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2 , 2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2'-biimidazole, 2,2'-bis(2,4-dichlorophenyl) )-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4-dibromophenyl)-4,4',5,5'-tetraphenyl -1,2'-biimidazole, 2,2'-bis(2,4,6-trichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 3-( 2-Methyl-2-dimethylaminopropionyl)carbazole, 3,6-bis(2-methyl-2-morpholinopropionyl)-9-n-dodecylcarbazole, 1-hydroxycyclohexyl phenylketone, bis(η5-2,4- cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium, 3,3',4,4'-tetrakis(tert-butylperoxycarbonyl) Benzophenone, 3,3',4,4'-tetrakis(tert-hexylperoxycarbonyl)benzophenone, 3,3'-bis(methoxycarbonyl)-4,4'-bis(tert-butylperoxycarbonyl)benzophenone, 3, 4'-bis(methoxycarbonyl)-4,3'-bis(tert-butylperoxycarbonyl)benzophenone, 4,4'-bis(methoxycarbonyl)-3,3'-bis(tert-butylperoxycarbonyl)benzophenone, 2-(3-Methyl-3H-benzothiazol-2-ylidene)-1-naphthalen-2-yl-ethanone, 2-(3-methyl-1,3-benzothiazol-2(3H)-ylidene)-1 -(2-benzoyl)ethanone and the like. The radical photopolymerization initiators may be used alone or in combination of two or more.

The radical polymerization method is not particularly limited, and emulsion polymerization, suspension polymerization, dispersion polymerization, precipitation polymerization, bulk polymerization, solution polymerization, and the like can be used.
The organic solvent used in the radical polymerization reaction is not particularly limited as long as it dissolves the produced polymer. Specific examples include the above-mentioned specific organic solvents, which may be used alone or in combination of two or more.

Furthermore, even a solvent that does not dissolve the produced polymer may be mixed with the above-mentioned organic solvent and used as long as the produced polymer does not precipitate.
In addition, since oxygen in an organic solvent becomes a cause of inhibiting the polymerization reaction in radical polymerization, it is preferable to use an organic solvent that has been degassed to the extent possible.
In addition, when the graft copolymer obtained by the above polymerization is dissolved in the reaction solution, the reaction solution may be used as it is for preparing the liquid crystal aligning agent, or the graft copolymer contained in the reaction solution may be dissolved in the reaction solution. After separation, the liquid crystal aligning agent may be prepared.
The polymerization temperature during radical polymerization can be any temperature in the range of 30 to 150°C, but is preferably in the range of 50 to 100°C. In addition, the reaction can be carried out at any concentration, but if the concentration is too low, it will be difficult to obtain a high molecular weight polymer, and if the concentration is too high, the viscosity of the reaction solution will become too high, making it difficult to stir uniformly. Therefore, the monomer concentration is preferably 1 to 50% by weight, more preferably 5 to 40% by weight. The initial stage of the reaction can be carried out at a high concentration, and then an organic solvent can be added.

In the radical polymerization reaction described above, if the ratio of the radical polymerization initiator to the monomer is large, the molecular weight of the obtained polymer will be small, and if it is small, the molecular weight of the obtained polymer will be large. The amount is preferably 0.1 to 10 mol% based on the monomer to be polymerized. Furthermore, various monomer components, solvents, initiators, etc. can be added during polymerization.

The polymer produced from the reaction solution obtained by the above reaction can be recovered by pouring the reaction solution into a poor solvent to precipitate it, but this reprecipitation treatment is not essential. Examples of the poor solvent used for precipitation include methanol, acetone, hexane, heptane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, diethyl ether, methyl ethyl ether, water, and the like. The polymer precipitated in a poor solvent can be collected by filtration and then dried under normal pressure or reduced pressure, at room temperature or by heating. Further, by repeating the operation of redissolving the recovered polymer in an organic solvent and reprecipitation recovery 2 to 10 times, the amount of impurities in the polymer can be reduced. Examples of the poor solvent in this case include alcohols, ketones, hydrocarbons, etc. It is preferable to use three or more kinds of poor solvents selected from these, since the efficiency of purification will further increase.

Considering the strength of the resulting coating film, workability during coating film formation, and uniformity of the coating film, the weight average molecular weight of the graft copolymer measured by GPC (Gel Permeation Chromatography) method is 2,000 to 5. ,000,000 is preferred, and 5,000 to 2,000,000 is more preferred.

Graft copolymers have branch polymers that are compatible with liquid crystals and trunk polymers that are not compatible with liquid crystals or become incompatible with heat, etc., and are characterized by being linked in a random arrangement by free radical polymerization. ing. This provides high seal adhesion, solvent selectivity, and coating properties.

In order to achieve both the coating properties, seal adhesion, film strength, and good weak anchoring properties of the weak anchoring alignment film, the introduction ratio of the branch polymer and the trunk polymer is also an important factor. For example, branch polymers play an important role in weak anchoring properties, and if their introduction ratio increases, the strength of the film will be impaired and heat curing will be inhibited, so it is necessary to consider the appropriate amount of introduction. be. On the other hand, the introduction amount and molecular weight of the backbone polymer do not affect the weak anchoring properties (they are small), so in order to achieve both of the above-mentioned properties, the monomer expressed by formula (6) used to synthesize the backbone polymer must be It is preferable that the ratio of the number of molecules (introduction ratio) of the macromonomer represented by formula (7) used in the synthesis of the branched polymer to the number of molecules is small. The preferred introduction ratio (macromonomer represented by formula (7)/monomer represented by formula (6)) is 0.1/99.9 to 50/50 (mol/mol), more preferably It is 0.2/99.8 to 30/70 (mol/mol).

(Polymer C)
The polymer C is a polymer that has a polymer unit that is compatible with the liquid crystal and reacts with the polymer β when heated.
Polymer C is a polymer obtained by polymerizing one or more monomers that have a group that reacts with polymer β when heated and is compatible with liquid crystal, and when it comes into contact with liquid crystal in a thin film state, it becomes liquid crystal. It is characterized by contributing to the formation of a weak anchoring state by being compatible with each other.

The present applicant has discovered that a weakly anchoring liquid crystal aligning agent containing a polymer such as Polymer C (a polymer that has a polymer unit that is compatible with the liquid crystal and reacts with other polymers that are used in combination) is easy to use. It is a weak anchoring liquid crystal aligning agent that can be manufactured in a number of steps, has good coating properties, has good adhesion to the seal, does not generate pre-tilt angles, and has low voltage drive and high-speed response when the voltage is turned off. We have found that it is possible to provide a weakly anchoring liquid crystal alignment film that can be realized at the same time, and have filed an application (Japanese Patent Application No. 2022-6921 and PCT/JP2023/1515, which claims priority to Patent Application No. 2022-6921. , the contents of this application are incorporated herein to the same extent as if expressly set forth in their entirety.)

One embodiment of the polymer C is a polymer represented by the following formula (8).

(In formula (8), A is an n-valent organic compound having a molecular weight of 500 or less and having a group that reacts with the polymer β upon heating, selected from the following formulas (8-A-1) to (8-A-16). represents a group.
Q is a divalent polymer unit which is compatible with the liquid crystal and contains as a constituent at least one kind selected from the group consisting of compounds represented by the above formulas (2) to (5).
R is a monovalent organic group selected from the following formulas (8-R-1) to (8-R-11) and having a molecular weight of 500 or less that does not react with the polymer β upon heating.
n is an integer from 1 to 2. When n is 2, the two Q's and R's may be the same or different. )

(In formulas (8-R-1) to (8-R-11), R ₁ and R ₂ each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and R ₃ and Each R ₄ independently represents a single bond or a linear or branched alkylene group having 1 to 12 carbon atoms. * represents a bonding site.)
The preferable range of the carbon number of the straight chain or branched alkyl group having 1 to 12 carbon atoms varies depending on each group, and may be, for example, 1 to 6 or 6 to 12.
The straight chain or branched alkylene group having 1 to 12 carbon atoms may have, for example, 1 to 6 carbon atoms or 1 to 3 carbon atoms.

The molecular weight of A in formula (8) is 500 or less.
The molecular weight of R in formula (8) is 500 or less.

A in formula (8) is a group selected from formulas (8-A-1) to (8-A-16) above. These are, for example, partial structures of a RAFT agent in RAFT polymerization and a chain transfer agent in chain transfer polymerization, which will be described later.
For example, the -S-C(=S)- group is an amino group, a protected amino group, a hydroxy group, a protected hydroxy group, a thiol group, a protected thiol group, a carboxy group, a protected carboxy group, an isocyanate group, a protected isocyanate group, a maleimide It reacts with groups such as carboxylic acid anhydride groups, vinyl groups, allyl groups, styryl groups, (meth)acrylic groups, and (meth)acrylamide groups.
The straight chain or branched alkyl group having 1 to 12 carbon atoms may have, for example, 1 to 6 carbon atoms or 1 to 3 carbon atoms.
The straight chain or branched alkylene group having 1 to 12 carbon atoms may have, for example, 1 to 6 carbon atoms or 1 to 3 carbon atoms.

R in formula (8) is a group selected from formulas (8-R-1) to (8-R-11) above. These are, for example, partial structures of RAFT agents in RAFT polymerization described below.

Q in formula (8) is a divalent polymer unit that is compatible with the liquid crystal and contains as a constituent component at least one selected from the group consisting of compounds represented by formulas (2) to (5) above. It is.

The monomer used in the synthesis of Polymer C may be a single component, or a combination of multiple monomers may be used. Further, other radically polymerizable monomers described below may be used in combination.

When the polymer C comes into contact with liquid crystal in a thin film state, it forms a polymer-liquid crystal mixed layer and exhibits weak anchoring properties. Optimization of the molecular weight is important because the thickness of the formed polymer-liquid crystal mixed layer changes depending on the molecular weight of the polymer C, and the weak anchoring property changes. From the viewpoint of forming a good weak anchoring film, the number average molecular weight of the polymer C is preferably 1,000 to 100,000, more preferably 3,000 to 50,000, and the weight average molecular weight (Mw) The molecular weight distribution (PDI) expressed as a ratio to the number average molecular weight (Mn) is preferably 3.0 or less, more preferably 2.0 or less.

The structure of Q in the polymer represented by formula (8), which is an example of polymer C, may be a single polymer structure using only one compound (monomer) represented by formulas (2) to (5) above. Alternatively, a copolymer structure consisting of a combination of a plurality of monomers may be used. When a plurality of monomers are combined, random copolymerization or block copolymerization may be used. When the monomers represented by the above formulas (2) to (5) are combined, the ratio is not particularly limited regardless of the method of combination. When combined with a compound species that becomes insolubilized in liquid crystal as described below, from the viewpoint of maintaining properties, the preferred combination ratio of compound species that becomes insolubilized in liquid crystal is 30 mol% or less, more preferably 20 mol% or less, but there are no limitations. do not. These synthesis methods, monomers to be combined, and combination ratios are preferably used within a range that allows desired physical properties, display characteristics, electrical characteristics, etc. to be obtained.

Examples of the compound species to be insolubilized in the liquid crystal include the compound represented by the above formula (6), the above-mentioned compound having a polymerizable group having a polymerizable unsaturated hydrocarbon group and a highly polar structure, and the above-mentioned polymerizable compound. Examples include compounds having a polymerizable group having a polymerizable unsaturated hydrocarbon group and a rigid structure, and compounds having a polymerizable group having a polymerizable unsaturated hydrocarbon group and a thermosetting structure.

Polymer C is preferably obtained by living polymerization or chain transfer polymerization.

When obtaining Polymer C, there is no need to particularly limit the polymerization method, but cationic polymerization and anionic polymerization often use alkali metals, metal complexes, and halogen compounds to generate active species, and in liquid crystal displays, Since the contamination of metal residues and halogen compounds can cause burn-in and display defects, it is preferable to use radical polymerization that uses no metals or halogen compounds as much as possible. Examples of living radical polymerization include living radical polymerization (NMP) using nitroxide as a dormant species, atom transfer radical polymerization (ATRP) using a metal complex, and reversible addition/elimination chain transfer polymerization (RAFT) using a sulfur compound as a dormant. Polymerization), living radical polymerization (TERP) using an organic tellurium compound, etc., and reversible transfer catalytic polymerization (RTCP) using an alkyl iodide compound as a dormant species and using a phosphorus compound, alcohol, etc. as a catalyst, etc. are preferred. Examples of the polymerization method include living radical polymerization such as NMP, RTCP, and RAFT polymerization, and NMP or RAFT polymerization is particularly preferred. It is also preferable to use chain transfer polymerization.

When chain transfer polymerization is used, examples of the polymerization initiator used include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, 1 , 1'-bis(tert-butylperoxy)cyclohexane, hydrogen peroxide, and the like. The proportion of the polymerization initiator used is usually 0.000001 to 0.1 part by mole, preferably 0.00001 to 0.01 part by mole, per 1 part by mole of the monomer used. As the chain transfer agent, it is preferable to use thiols, and specific examples include compounds represented by the following formulas (S-1) to (S-15). The proportion of the chain transfer agent used is usually 0.000001 to 0.1 part by mole, preferably 0.00001 to 0.01 part by mole, per 1 part by mole of the monomer used. The reaction temperature in the above polymerization is preferably 20 to 200°C, more preferably 40 to 150°C, and the reaction time is preferably 1 to 168 hours, more preferably 8 to 72 hours.

(In formulas (S-1) to (S-15), Me represents a methyl group, and Et represents an ethyl group.)

The organic solvent used in the chain transfer polymerization reaction is not particularly limited as long as it can dissolve the produced polymer. Specific examples include the above-mentioned specific organic solvents, which may be used alone or in combination of two or more.
Furthermore, even a solvent that does not dissolve the produced polymer may be mixed with the above-mentioned organic solvent and used as long as the produced polymer does not precipitate.
Note that in chain transfer polymerization, oxygen in the organic solvent becomes a cause of inhibiting the polymerization reaction, so it is preferable to use an organic solvent that has been degassed to the extent possible.

By using chain transfer polymerization, it is possible to control polymer terminals, molecular weight, and molecular weight distribution.

In chain transfer polymerization, polymers are obtained by competitive reactions between chain transfer and growth reactions. The molecular weight and molecular weight distribution of a polymer obtained by chain transfer polymerization are determined by the chain transfer constant (Cs), which is expressed as the quotient of the chain transfer rate constant (kc) and the growth rate constant (kp). Generally, in chain transfer polymerization, a structure in which Cs is in the range of 1 to 60 is preferable, and it is important to use the monomer species and chain transfer agent species and the correct combination of these.

The chain transfer constant (Cs) varies greatly depending on the type of monomer used and the type of chain transfer agent, so it is necessary to select it correctly.

The polymer C is preferably composed of one or more compound species that are compatible with the liquid crystal from the viewpoint of maintaining properties, but a small amount of compound species that are not compatible with the liquid crystal or become insolubilized in the liquid crystal upon firing may also be introduced. be able to. A preferred combination ratio of monomers that are insolubilized in liquid crystal is 30 mol% or less, more preferably 20 mol% or less, but is not limited. These synthesis methods, monomers to be combined, and combination ratios are preferably used within a range that allows desired physical properties, display characteristics, electrical characteristics, etc. to be obtained.

One embodiment of the polymer alloy of the present invention includes a polymer C that is obtained by polymerizing one or more monomers that have a group that reacts with the polymer β when heated and is compatible with the liquid crystal; It is characterized by containing a polymer β that suppresses the elution of the polymer C into the liquid crystal by reacting with the polymer C by heating. This provides high seal adhesion, solvent selectivity, and coating properties.

The temperature at which the group in polymer C that reacts with polymer β when heated and the site in polymer β that reacts with polymer C when heated is not particularly limited, but for example, even if it is 150°C or higher. Alternatively, the temperature may be 200°C or higher.

The polymer alloy of the present invention consists of a polymer α, which is a component that exhibits weak anchoring properties, and a component that does not exhibit weak anchoring properties, but which develops a uniaxial orientation regulating force through orientation treatment (preferably uniaxial orientation treatment). It is characterized by containing a certain polymer β, and the weak anchoring alignment film obtained using this is subjected to alignment treatment (preferably uniaxial alignment treatment) to improve weak anchoring properties and high-speed response when voltage is turned off. It is possible to achieve both. Furthermore, by selecting an appropriate polymer for the polymer β, good applicability and good seal adhesion can be obtained.

The heating temperature of the polymer alloy of the present invention is not particularly limited, but may be, for example, 150°C or higher, or 200°C or higher.

In order to achieve both the coating properties, seal adhesion, film strength, and good weak anchoring properties of the weak anchoring alignment film, it is essential to use the polymer α and the polymer β together. In addition, the mixing ratio of polymer α and polymer β is an important factor.
For example, polymer α, which is a component that exhibits weak anchoring properties, plays an important role, and if the proportion of polymer α that is introduced increases, the strength of the film may be impaired or heat curing may be inhibited. Therefore, it is necessary to consider the appropriate amount to introduce. On the other hand, the amount and molecular weight of polymer β introduced do not affect the weak anchoring properties (they are small), so in order to suitably achieve both of the above-mentioned properties, the mass ratio of polymer β to polymer α must be made small. preferable.
The mass ratio (polymer α/polymer β) is preferably 10/90 to 99.9/0.1 (mass ratio), more preferably 30/70 to 99.5/0.5 (mass ratio). , 50/50 to 99.0/1.0 (mass ratio) is particularly preferred.

(Polymer β)
The polymer β does not exhibit weak anchoring properties, but exhibits a uniaxial alignment regulating force when subjected to alignment treatment (preferably uniaxial alignment treatment). The polymer β is preferably a polymer that functions as a strong anchoring alignment film by itself. Suitable uniaxial alignment treatment methods include photo alignment treatment, rubbing alignment treatment, and the like. By performing uniaxial alignment treatment such as photo alignment treatment or rubbing alignment treatment on the weak anchoring alignment film composed of polymer α and polymer β, only the polymer β is uniaxially aligned, and the weak anchoring alignment film is formed on the weak anchoring alignment film. Both an anchoring region and a strong anchoring region can be formed, thereby achieving high-speed response.
In addition, by selecting an appropriate polymer β, it can be fixed to the substrate, cross-linked between polymers, and cross-linked with the sealing component, resulting in excellent film hardness and seal adhesion strength, excellent solvent selectivity, and excellent coating properties. An anchoring liquid crystal aligning agent and a display element using the same can be obtained.
Furthermore, when polymer C is used as polymer α, polymer β reacts with polymer C by heating, thereby suppressing elution of polymer C into the liquid crystal.

In order to obtain the desired effect, it is important that polymer α and polymer β undergo phase separation in a sea-island pattern on the surface of the weakly anchored alignment film to create a segmented surface state. In order to induce sea-island phase separation, it is necessary that the physical properties (thermal expansion coefficient and polarity) of polymer α and polymer β are significantly different, and that polymer α is hydrophobic, flexible, and has a low Tg. The polymer β is preferably a highly polar and rigid polymer.

The polymer β is preferably at least one kind of polymer selected from the group consisting of polyimide, polyamic acid, polyamic acid ester, polyamide, polyurea, and poly(meth)acrylate, and particularly preferably polyimide, polyamic acid, and polyamic acid ester. It is an acid ester and poly(meth)acrylate.

The polymer β is a polymer (hereinafter referred to as (sometimes referred to as "polyimide polymer") is preferable.
The tetracarboxylic acid derivative component includes at least one compound selected from the group consisting of tetracarboxylic dianhydride and derivatives thereof.
Examples of the polyimide precursor include polyamic acid and polyamic acid ester.
When selecting polyamic acid as the polymer β, it can be obtained, for example, by subjecting a tetracarboxylic acid derivative component to a diamine component to a polymerization (polycondensation) reaction. Furthermore, when polyimide is selected as the polymer β, it can be obtained by imidizing the above-mentioned polyamic acid. Furthermore, when a polyamic acid ester is selected as the polymer β, it can be obtained by the method described below. Note that polyimide can also be obtained by imidizing the polyamic acid ester.

Examples of the above-mentioned tetracarboxylic acid derivative component include aromatic tetracarboxylic dianhydride, acyclic aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, or derivatives thereof. Here, the aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups including at least one carboxy group bonded to an aromatic ring. Acyclic aliphatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups bonded to a chain hydrocarbon structure. However, it is not necessary to consist only of a chain hydrocarbon structure, and a part thereof may have an alicyclic structure or an aromatic ring structure.

Moreover, an alicyclic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups including at least one carboxy group bonded to an alicyclic structure. However, none of these four carboxy groups is bonded to an aromatic ring.
Further, it is not necessary to be composed only of an alicyclic structure, and a part thereof may have a chain hydrocarbon structure or an aromatic ring structure.

The aromatic tetracarboxylic dianhydride, acyclic aliphatic tetracarboxylic dianhydride or alicyclic tetracarboxylic dianhydride is, among others, a tetracarboxylic dianhydride represented by the following formula (9). is preferred.

(X represents a structure selected from the group consisting of the following formulas (X-1) to (X-17) and (XR-1) to (XR-2).)

(In formulas (X-1) to (X-17), R ₁ to R ₄ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, Alkynyl group having 2 to 6 carbon atoms, monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, alkoxy group having 1 to 6 carbon atoms, alkoxyalkyl group having 2 to 6 carbon atoms, 2 to 6 carbon atoms represents an alkyloxycarbonyl group or a phenyl group. R ₅ and R ₆ each independently represent a hydrogen atom or a methyl group.
In formulas (XR-1) to (XR-2), j and k are integers of 0 or 1, and A ₁ and A ₂ each independently represent a single bond, -O-, -CO-, -COO-, represents a phenylene group, a sulfonyl group, or an amide group. The plurality of _A2 's may be the same or different.
*1 is a bond bonded to one acid anhydride group, and *2 is a bond bonded to the other acid anhydride group. )

As a preferable specific example of the tetracarboxylic dianhydride represented by the above formula (9), X is represented by the above formulas (X-1) to (X-8), (X-10) to (X-11). , and those selected from (XR-1) to (XR-2).

The above formula (X-1) is preferably selected from the group consisting of the following formulas (X1-1) to (X1-6).

(In formulas (X1-1) to (X1-6), *1 is a bond that is bonded to one acid anhydride group, and *2 is a bond that is bonded to the other acid anhydride group.)

Preferred specific examples of the above formulas (XR-1) and (XR-2) include the following formulas (XR-3) to (XR-18).

(* represents a bond.)

When producing a polyimide polymer, the amount of the tetracarboxylic dianhydride or its derivative represented by the above formula (9) to be used is as follows: The content is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 20 mol% or more.

The diamine component used in the production of the polyimide polymer is not particularly limited, but a diamine component containing a diamine represented by the following formula (10) is preferred.

(In formula (10), Ar ₁ and Ar _1' each independently represent a benzene ring, a biphenyl structure, or a naphthalene ring, and one or more of the benzene ring, the biphenyl structure, or the naphthalene ring The hydrogen atom of may be substituted with a monovalent group. L ₁ and L _1' each independently represent a single bond, -O-, -C(=O)-, or -O-C(= O)-.A represents -CH ₂ -, an alkylene group having 2 to 12 carbon atoms, or between the carbon-carbon bond of the alkylene group, -O-, -C(=O)-O-, Represents a divalent organic group in which at least one of the following groups is inserted:

Ar ₁ and Ar _1' in the above formula (10) each represent a benzene ring, a biphenyl structure, or a naphthalene ring. One or more hydrogen atoms on the benzene ring, biphenyl structure, or naphthalene ring may be substituted with a monovalent group, and the monovalent group includes a halogen atom, an alkyl group having 1 to 3 carbon atoms, a carbon Alkenyl group having 2 to 3 carbon atoms, alkoxy group having 1 to 3 carbon atoms, fluoroalkyl group having 1 to 3 carbon atoms, fluoroalkenyl group having 2 to 3 carbon atoms, fluoroalkoxy group having 1 to 3 carbon atoms, 2 carbon atoms -3 alkyloxycarbonyl groups, cyano groups, nitro groups, etc.

In Ar ₁ and Ar _1' of the above formula (10), the bonding position of the amino group and L ₁ or L _1' to the benzene ring is preferably the 1,4-position or the 1,3-position. , 1,4-position is more preferred. The binding position of the amino group and L ₁ or L _1' to the biphenyl structure is more preferably the 4,4'-position or the 3,3'-position, and even more preferably the 4,4'-position. The bonding position of the amino group and L ₁ or L _1' to the naphthalene ring is preferably the 1,5-position or the 2,6-position, and even more preferably the 2,6-position.

A in the above formula (10) represents -CH ₂ -, an alkylene group having 2 to 12 carbon atoms, or -O-, -C( Represents a divalent organic group into which at least one of =O)-O- and -OC(=O)- is inserted. Any hydrogen atom that A has may be substituted with a halogen atom.
The alkylene group having 2 to 12 carbon atoms may be linear or branched, but is preferably linear.
-O-, -C(=O)-O-, and -OC(=O)- inserted into the divalent organic group may be one or more. good.

Preferred specific examples of the group -L ₁ -AL _1' - in the above formula (10) are listed below.
-(CH ₂ ) _n -,
-O-(CH ₂ ) _n -,
-O-(CH ₂ ) _n -O-,
-C(=O)-(CH ₂ ) _n -C(=O)-,
-O-C(=O)-(CH ₂ ) _n -O-,
-OC(=O)-(CH ₂ ) _n -OC(=O)-,
-O-C(=O)-(CH ₂ ) _n -C(=O)-O-,
-C(=O)-O-(CH ₂ ) _n -O-C(=O)-,
-(CH ₂ ) _m1 -O-(CH ₂ ) _n' -O-(CH ₂ ) _m2 -,
-(CH ₂ ) _m1 -O-C(=O)-(CH ₂ ) _n' -C(=O)-O-(CH ₂ ) _m2 -,
-(CH ₂ ) _m1 -C(=O)-O-(CH ₂ ) _n' -O-C(=O)-(CH ₂ ) _m2 -

In preferred specific examples of the group -L ₁ -AL _1' -, n is an integer of 1 to 12, more preferably an integer of 2 to 12, even more preferably an integer of 2 to 6.
The sum of m1, m2 and n' is an integer of 3 to 12, more preferably an integer of 6 to 12. m1 and m2 are each more preferably an integer of 1 to 4, even more preferably an integer of 2 to 4. n' is more preferably an integer of 2 to 6, even more preferably an integer of 2 to 4.

The proportion of the diamine represented by formula (10) is preferably 1 mol% or more, more preferably 10 mol% or more, and even more preferably 20 mol% or more, based on 1 mol of the diamine component. preferable.

The diamine component constituting the polyimide polymer may contain other diamines than the diamines described above. Examples of other diamines are listed below, but the present invention is not limited thereto. In addition to the diamine represented by the above formula (10), when other diamines are used together, the amount of the diamine represented by the formula (10) relative to the diamine component is preferably 90 mol% or less, and 80 mol% The following are more preferred. Examples of other diamines are listed below, but the other diamines in the present invention are not limited to these. The other diamines mentioned above may be used alone or in combination of two or more.

p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 1, 4-Diamino-2,5-dimethoxybenzene, 2,5-diaminotoluene, 2,6-diaminotoluene, 4-aminobenzylamine, 2-(4-aminophenyl)ethylamine, 4-(2-(methylamino) ethyl)aniline, 4-(2-aminoethyl)aniline, 2-(6-amino-2-naphthyl)ethylamine, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4 , 4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3-trifluoromethyl-4,4'-diaminobiphenyl , 2-trifluoromethyl-4,4'-diaminobiphenyl, 3-fluoro-4,4'-diaminobiphenyl, 2-fluoro-4,4'-diaminobiphenyl, 2,2'-difluoro-4,4' -diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-bis(trifluoromethyl) -4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 1 , 5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene;
N,N'-bis(4-aminophenyl)-cyclobutane-(1,2,3,4)-tetracarboxylic acid diimide, N,N'-bis(4-aminophenyl)-1,3-dimethylcyclobutane- (1,2,3,4)-Tetracarboxylic acid diimide, N,N'-bis(2,2'-bis(trifluoromethyl)-4'-amino-1,1'-biphenyl-4-yl) -Diamine having a tetracarboxylic acid diimide structure such as -cyclobutane-(1,2,3,4)-tetracarboxylic acid diimide;

1,4-phenylene bis(4-aminobenzoate), 1,4-phenylene bis(3-aminobenzoate), 1,3-phenylene bis(4-aminobenzoate), 1,3-phenylene bis(3-aminobenzoate) ), bis(4-aminophenyl) terephthalate, bis(3-aminophenyl) terephthalate, bis(4-aminophenyl) isophthalate, bis(3-aminophenyl) isophthalate;
4,4'-diaminoazobenzene, diaminotolane, 4,4'-diaminochalcone, or [4-[(E)-3-[2-(2,4-diaminophenyl)ethoxy]-3-oxo-proper- 1-enyl]phenyl]4-(4,4,4-trifluorobutoxy)benzoate, or [4-[(E)-3-[[5-amino-2-[4-amino-2-[[( E) -3-[4-[4-(4,4,4-trifluorobutoxy)benzoyl]oxyphenyl]prop-2-enoyl]oxymethyl]phenyl]phenyl]methoxy]-3-oxo-prop-1 -enyl]phenyl]4-(4,4,4-trifluorobutoxy) diamine having a photo-alignable group such as an aromatic diamine having a cinnamate structure typified by benzoate;
A diamine having a terminal photopolymerizable group such as 2-(2,4-diaminophenoxy)ethyl methacrylate or 2,4-diamino-N,N-diallylaniline;
1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropanone, 2-(4-(2-hydroxy-2-methylpropanoyl)phenoxy)ethyl Diamine having a radical polymerization initiator function such as 3,5-diaminobenzoate;
Diamines having an amide bond such as 4,4'-diaminobenzanilide;
Diamines having a urea bond such as 1,3-bis(4-aminophenyl)urea;
H ₂ N-Y _D -NH ₂ (Y _D is a divalent organic group having -N(D)- (D represents a protective group that is removed by heating and replaced with a hydrogen atom) in the molecule. diamine having a thermally releasable group such as );

3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 4,4'-sulfonyldianiline, 3,3'-sulfonyldianiline, bis(4-aminophenyl)silane , bis(3-aminophenyl)silane, dimethyl-bis(4-aminophenyl)silane, dimethyl-bis(3-aminophenyl)silane, 4,4'-thiodianiline, 3,3'-thiodianiline, 4,4' -diaminobenzophenone, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(4-aminobenzyl)benzene;
2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 1,4-bis-(4-aminophenyl )-piperazine, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N-[3-(1H-imidazol-1-yl)propyl] 3 , 5-diaminobenzamide, 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-4-methyl-2-oxazolyl]-benzenamine, 4-[4-[(4-aminophenoxy) ) methyl]-4,5-dihydro-2-oxazolyl]-benzenamine, 1,4-bis(p-aminobenzyl)piperazine, 4,4'-propane-1,3-diylbis(piperidine-1,4- diyl)dianiline, 4-(4-aminophenoxycarbonyl)-1-(4-aminophenyl)piperidine, 2,5-bis(4-aminophenyl)pyrrole, 4,4'-(1-methyl-1H-pyrrole) -2,5-diyl)bis[benzenamine], 1,4-bis-(4-aminophenyl)-piperazine, 2-N-(4-aminophenyl)pyridine-2,5-diamine, 2-N- (5-Aminopyridin-2-yl)pyridine-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6-aminobenzimidazole, 5- Heterocycle-containing diamines such as (1H-benzimidazol-2-yl)benzene-1,3-diamine or diamines represented by the following formulas (Z-1) to (Z-5), or 4,4 '-Diaminodiphenylamine, 4,4'-diaminodiphenyl-N-methylamine, N,N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N' -Heterocycle containing a nitrogen atom, typified by diamine having a diphenylamine structure such as dimethylbenzidine or N,N'-bis(4-aminophenyl)-N,N'-dimethyl-1,4-benzenediamine , at least one nitrogen atom-containing structure selected from the group consisting of secondary or tertiary amino groups (wherein -N(D)- (D represents a protective group that is removed by heating and replaced with a hydrogen atom). (excluding amino groups derived from );

2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diamino-3,3'-dihydroxy biphenyl;
2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 1,2-bis(4-aminophenyl)ethane-3-carboxylic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl-4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 1, Diamines having a carboxy group such as 2-bis(4-aminophenyl)ethane-3,3'-dicarboxylic acid and 4,4'-diaminodiphenyl ether-3,3'-dicarboxylic acid;
1-(4-aminophenyl)-1,3,3-trimethyl-1H-indan-5-amine, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H- inden-6-amine;
Cholestanyloxy-3,5-diaminobenzene, Cholestanyloxy-3,5-diaminobenzene, Cholestanyloxy-2,4-diaminobenzene, Cholestanyl 3,5-diaminobenzoate, Cholestenyl 3,5-diaminobenzoate , diamines having a steroid skeleton such as lanostanil 3,5-diaminobenzoate and 3,6-bis(4-aminobenzoyloxy)cholestane;
Diamines represented by the following formulas (V-1) to (V-2);
Diamines having a siloxane bond such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane;
Acyclic aliphatic diamines such as metaxylylene diamine, 1,3-propanediamine, tetramethylene diamine, pentamethylene diamine, hexamethylene diamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, Alicyclic diamine such as 4,4'-methylenebis(cyclohexylamine), two amino groups in the group represented by any of the formulas (Y-1) to (Y-167) described in WO2018/117239 conjugated diamines, etc.

(In formula (V-1), m and n are each independently an integer of 1 to 3 (provided that 1≦m+n≦4 is satisfied), j is an integer of 0 or 1, and X ₁ is -(CH ₂ ) _a - (a is an integer from 1 to 15), -CONH-, -NHCO-, -CO-N(CH ₃ )-, -NH-, -O-, -CH ₂ O-, -CH ₂ -OCO-, -COO-, or -OCO-. R ₁ is a fluorine atom, a fluorine atom-containing alkyl group having 1 to 10 carbon atoms, or a fluorine atom-containing group having 1 to 10 carbon atoms. Represents an alkoxy group, an alkyl group having 3 to 10 carbon atoms, an alkoxy group having 3 to 10 carbon atoms, or an alkoxyalkyl group having 3 to 10 carbon atoms.
In formula (V-2), X ₂ represents -O-, -CH ₂ O-, -CH ₂ -OCO-, -COO-, or -OCO-, and R ₂ is alkyl having 3 to 30 carbon atoms. group, or a fluorine atom-containing alkyl group having 3 to 20 carbon atoms.
When two of m, n, X ₁ and R ₁ are present, each independently has the above definition. )

In addition, D in -N(D)- of the other diamines mentioned above is representative of benzyloxycarbonyl group, 9-fluorenylmethyloxycarbonyl group, allyloxycarbonyl group, Boc (tert-butoxycarbonyl group), etc. Preferred are carbamate-based organic groups. Boc is particularly preferred from the viewpoint that it has good thermal desorption efficiency, desorbs at a relatively low temperature, and is discharged as a harmless gas upon desorption.

Preferred examples of diamines having a thermally releasable group exemplified as other diamines include diamines selected from the following formulas (d-1) to (d-7).

(In formulas (d-2), (d-6), and (d-7), R represents a hydrogen atom or Boc.)

When using a diamine having a heat-eliminating group as described above as a diamine component used in the production of a polyimide polymer, from the viewpoint of suitably obtaining the effects of the present invention, it is preferably 5 to 40% per mole of the diamine component. It is preferably mol%, more preferably 5 to 35 mol%, even more preferably 5 to 30 mol%.

The above polymer β is a polyimide precursor obtained using a diamine component containing a diamine having a nitrogen atom-containing structure, and a polyimide precursor obtained from the viewpoint of reducing afterimages derived from residual DC or improving electrical properties. It may contain at least one kind of polymer selected from the group consisting of imidides (hereinafter also referred to as polyimide polymer (Q)).
Examples of the tetracarboxylic acid derivative component for obtaining the polyimide polymer (Q) include the above-mentioned tetracarboxylic acid derivative component. Among these, the tetracarboxylic dianhydride represented by the above formula (9) or a derivative thereof is preferred. The amount of the tetracarboxylic dianhydride or its derivative represented by the above formula (9) to be used is preferably 10 mol% or more, and 20 mol% based on 1 mol of the total tetracarboxylic acid derivative component to be reacted with the diamine component. The above is more preferable.
As the diamine component for obtaining the polyimide polymer (Q), the amount of the diamine having the nitrogen atom-containing structure used is 5 to 50% based on the total amount of the diamine component for obtaining the polyimide polymer (Q). It is preferably 100 mol%, more preferably 10 to 95 mol%, even more preferably 20 to 80 mol%.
The diamine component for obtaining the polyimide polymer (Q) may further contain a diamine other than the diamine having the nitrogen atom-containing structure. A more preferable example is a diamine (hereinafter also referred to as diamine (c)) having in its molecule at least one group selected from the group consisting of a urea bond, an amide bond, a carboxy group, and a hydroxy group. The amount of diamine (c) used is preferably 1 to 95 mol%, more preferably 5 to 90 mol%, and 20 to 80 mol% based on the total amount of diamine components to obtain the polyimide polymer (Q). is even more preferable.

The polymer β is selected from the group consisting of a polyimide precursor obtained using the above polyimide polymer (Q) and a diamine component not containing a diamine having a nitrogen atom-containing structure, and an imidized product of the polyimide precursor. It may be a mixture with at least one kind of polymer (hereinafter also referred to as polyimide polymer (H)). The content ratio of polyimide polymer (Q) and polyimide polymer (H) is 10/90 to 90/mass ratio of [polyimide polymer (Q)]/[polyimide polymer (H)]. The ratio is preferably 10, more preferably 20/80 to 80/20, even more preferably 30/70 to 70/30.

In order to react with the polymer C by heating, the polymer β has an amino group, a protected amino group, a hydroxy group, a protected hydroxy group, a thiol group, a protected thiol group, a carboxy group, a protected carboxy group, an isocyanate group, a protected isocyanate group, A polymer containing at least one selected from the group consisting of a maleimide group, a carboxylic anhydride group, a vinyl group, an allyl group, a styryl group, a (meth)acrylic group, and a (meth)acrylamide group as a site that reacts with polymer C. It is preferable that
Here, the protecting group for the protected amino group, the protecting group for the protected hydroxy group, the protecting group for the protected thiol group, the protecting group for the protected carboxy group, and the protecting group for the protected isocyanate group are removed by heating, and the amino group, Represents a group that produces a hydroxy group, thiol group, carboxy group, or isocyanate group.
Examples of the protecting group for the protected amino group include tert-butoxycarbonyl group, benzyloxycarbonyl group, 9-fluorenylmethyloxycarbonyl group, allyloxycarbonyl group, phthaloyl group, nitrobenzenesulfonyl group, (2-trimethylsilyl)- Examples include ethanesulfonyl group, 2,2,2-trichloroethoxycarbonyl group, and azide group.
Examples of the protecting group for the protected hydroxy group include a tetrahydropyranyl group, a methoxymethyl ether group, a trityl group, a tert-butyl group, a trialkylsilyl group, a tert-butoxycarbonyl group, a benzyl group, and an acetyl group.
Examples of the protecting group for the protected thiol group include tert-butoxycarbonyl group, benzyloxycarbonyl group, 9-fluorenylmethyloxycarbonyl group, allyloxycarbonyl group, phthaloyl group, nitrobenzenesulfonyl group, (2-trimethylsilyl)- Examples include ethanesulfonyl group, 2,2,2-trichloroethoxycarbonyl group, and azide group.
Examples of the protecting group for the protected carboxy group include a methyl ester group, a benzyl ester group, and a tert-butyl ester group.
Examples of the protecting group for the protected isocyanate group include a tert-butyl group, a dimethylpyrazole group, a methyl ethyl ketone oxime group, and a lactam group.

When polyamic acid, polyimide, or polyamic acid ester is used as the polymer β, a carboxy group generated from the reaction of a tetracarboxylic dianhydride and a diamine component is present, and the terminal group of the polymer chain is a carboxylic acid (anhydride) or an amino acid. Because of the presence of the group, all polyamic acids and polyimides fall under the polymer β unless the imidization rate is 100%.

<Method for manufacturing polyimide precursor>
Polyamic acid, which is one of the polyimide precursors, can be produced by the following method. Specifically, a tetracarboxylic acid derivative component and a diamine component are reacted in the presence of an organic solvent at -20 to 150°C, preferably 0 to 50°C, for 30 minutes to 24 hours, preferably 1 to 12 hours. It can be synthesized by a condensation reaction).
Specific examples of the organic solvent used in the above reaction include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, Examples include 1,3-dimethyl-2-imidazolidinone. In addition, if the polymer has high solvent solubility, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene Glycol monopropyl ether, diethylene glycol monomethyl ether, or diethylene glycol monoethyl ether can be used. These may be used in combination of two or more types.

The reaction can be carried out at any concentration, preferably 1 to 50% by mass, more preferably 5 to 30% by mass. It is also possible to carry out the reaction at a high concentration in the initial stage and then add a solvent. In the reaction, the ratio of the total number of moles of the diamine component to the total number of moles of the tetracarboxylic acid derivative component is preferably 0.8 to 1.2. As in normal polycondensation reactions, the closer this molar ratio is to 1.0, the greater the molecular weight of the polyamic acid produced.

The polyamic acid obtained in the above reaction can be recovered by precipitating the polyamic acid by injecting the reaction solution into a poor solvent while thoroughly stirring the reaction solution. Further, purified polyamic acid powder can be obtained by performing precipitation several times, washing with a poor solvent, and drying at room temperature or by heating. Examples of the poor solvent include, but are not limited to, water, methanol, ethanol, hexane, butyl cellosolve, acetone, toluene, and the like.

A polyamic acid ester, which is one of the polyimide precursors, can be produced by (1) a method of esterifying the above-mentioned polyamic acid, (2) a method of reacting a tetracarboxylic acid derivative component containing a tetracarboxylic acid diester dichloride with a diamine component, ( 3) It can be produced by a known method such as a method of polycondensing a tetracarboxylic acid derivative component containing a tetracarboxylic diester with a diamine.

The above-mentioned polyamic acid and polyamic acid ester may be terminal-modified polymers obtained by using an appropriate end-capping agent together with the above-mentioned tetracarboxylic acid derivative component and diamine component. .
Examples of the terminal capping agent include acetic anhydride, maleic anhydride, nadic anhydride, phthalic anhydride, itaconic anhydride, 1,2-cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, and trimellitic anhydride. , 3-(3-trimethoxysilyl)propyl)-3,4-dihydrofuran-2,5-dione, 4,5,6,7-tetrafluoroisobenzofuran-1,3-dione, 4-ethynyl phthalic acid Acid monoanhydrides such as anhydrides; dicarbonate diester compounds such as di-tert-butyl dicarbonate and diallyl dicarbonate; chlorocarbonyl compounds such as acryloyl chloride, methacryloyl chloride, and nicotinic acid chloride; aniline, 2-aminophenol, 3 -Aminophenol, 4-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, cyclohexylamine, n-butylamine, n-pentylamine, n - Monoamine compounds such as hexylamine, n-heptylamine, n-octylamine; unsaturated compounds such as ethyl isocyanate, phenyl isocyanate, naphthyl isocyanate, 2-acryloyloxyethyl isocyanate and 2-methacryloyloxyethyl isocyanate Monoisocyanate compounds such as isocyanate having a bond; isothiocyanate compounds such as ethyl isothiocyanate and allyl isothiocyanate; and the like.
The proportion of the terminal capping agent used is preferably 40 parts by mole or less, more preferably 30 parts by mole or less, based on a total of 100 parts by mole of the diamine component used.

Polyimide can be produced by imidizing the above polyimide precursor by a known method.
In polyimide, the ring closure rate (also referred to as imidization rate) of functional groups possessed by polyamic acid or polyamic acid ester does not necessarily have to be 100%, and can be arbitrarily adjusted depending on the use and purpose.

The method for obtaining polyimide by imidizing the polyamic acid or polyamic acid ester includes thermal imidization in which the solution of the polyamic acid or polyamic acid ester is directly heated, or a catalyst (e.g. Examples include catalytic imidization in which a basic catalyst such as pyridine or an acid anhydride such as acetic anhydride is added.

The polyamic acid, polyamic acid ester, and polyimide used in the present invention preferably have a solution viscosity of, for example, 10 to 1000 mPa·s when made into a solution with a concentration of 10 to 15% by mass, from the viewpoint of workability. , not particularly limited. Note that the solution viscosity (mPa・s) of the above polymer is a polymer with a concentration of 10 to 15% by mass prepared using a good solvent for the polymer (for example, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.). This is the value measured for the solution at 25°C using an E-type rotational viscometer.

The weight average molecular weight (Mw) of the polyamic acid, polyamic acid ester, and polyimide measured by gel permeation chromatography (GPC) in terms of polystyrene is preferably 1,000 to 500,000, more preferably 2,000. ~500,000. Further, the molecular weight distribution (Mw/Mn) expressed as the ratio of Mw to the number average molecular weight (Mn) in terms of polystyrene measured by GPC is preferably 15 or less, more preferably 10 or less. By having a molecular weight within such a range, good liquid crystal alignment of the liquid crystal display element can be ensured.

When polyurea is selected as the polymer β, the diisocyanate to be reacted with the above-mentioned diamine component is not particularly limited and can be used depending on availability and the like. The specific structure of the diisocyanate is shown below.

In the formula, R ₂ and R ₃ represent an aliphatic hydrocarbon group having 1 to 10 carbon atoms.

Although the aliphatic diisocyanates shown in formulas (K-1) to (K-5) are inferior in reactivity, they have the advantage of improving solvent solubility; Aromatic diisocyanates are highly reactive and have the effect of improving heat resistance, but they have the disadvantage of decreasing solvent solubility. In terms of versatility and characteristics, formulas (K-1), (K-7), (K-8), (K-9), and (K-10) are preferable, and in terms of electrical characteristics, formula (K-12) is preferable. ), formula (K-13) is preferred from the viewpoint of liquid crystal orientation. Two or more diisocyanates can be used in combination, and it is preferable to use various diisocyanates depending on the desired properties.

In addition, some diisocyanates can be replaced with the above-mentioned tetracarboxylic dianhydride, and they can also be used in the form of a copolymer of polyamic acid and polyurea, and chemical imidization can be used to create a copolymer of polyimide and polyurea. It may also be used in the form of a copolymer.

When polyamide is selected as the polymer β, the structure of the dicarboxylic acid to be reacted is not particularly limited, but specific examples are as follows.

Examples of aliphatic dicarboxylic acids include malonic acid, oxalic acid, dimethylmalonic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, muconic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, and 2,2-dimethylglutaric acid. Mention may be made of acids, dicarboxylic acids such as 3,3-diethylsuccinic acid, azelaic acid, sebacic acid and suberic acid.
Examples of alicyclic dicarboxylic acids include 1,1-cyclopropanedicarboxylic acid, 1,2-cyclopropanedicarboxylic acid, 1,1-cyclobutanedicarboxylic acid, 1,2-cyclobutanedicarboxylic acid, and 1,3-cyclobutanedicarboxylic acid. acid, 3,4-diphenyl-1,2-cyclobutanedicarboxylic acid, 2,4-diphenyl-1,3-cyclobutanedicarboxylic acid, 1-cyclobutene-1,2-dicarboxylic acid, 1-cyclobutene-3,4-dicarboxylic acid Acid, 1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,1-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexane Dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,4-(2-norbornene)dicarboxylic acid, norbornene-2,3-dicarboxylic acid, bicyclo[2.2.2]octane-1,4-dicarboxylic acid, bicyclo [2.2.2] Octane-2,3-dicarboxylic acid, 2,5-dioxo-1,4-bicyclo[2.2.2]octanedicarboxylic acid, 1,3-adamantanedicarboxylic acid, 4,8- Examples include dioxo-1,3-adamantane dicarboxylic acid, 2,6-spiro[3.3]heptane dicarboxylic acid, 1,3-adamantane diacetic acid, and camphoric acid.
Aromatic dicarboxylic acids include o-phthalic acid, isophthalic acid, terephthalic acid, 5-methylisophthalic acid, 5-tert-butyl isophthalic acid, 5-aminoisophthalic acid, 5-hydroxyisophthalic acid, 2,5-dimethylterephthalic acid. Acid, tetramethyl terephthalic acid, 1,4-naphthalene dicarboxylic acid, 2,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, 1,4-anthracene dicarboxylic acid, 1,4 -Anthraquinonedicarboxylic acid, 2,5-biphenyldicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 1,5-biphenylenedicarboxylic acid, 4,4''-terphenyldicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 4 , 4'-diphenyletherdicarboxylic acid, 4,4'-diphenylpropanedicarboxylic acid, 4,4'-diphenylhexafluoropropanedicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, 4,4'-bibenzyldicarboxylic acid, 4,4'-Stilbendicarboxylic acid, 4,4'-trandicarboxylic acid, 4,4'-carbonyl dibenzoic acid, 4,4'-sulfonyl dibenzoic acid, 4,4'-dithiodibenzoic acid, p- Phenylene diacetic acid, 3,3'-p-phenylene dipropionic acid, 4-carboxycinnamic acid, p-phenylene diacrylic acid, 3,3'-[4,4'-(methylenedi-p-phenylene)]dipropion acid, 4,4'-[4,4'-(oxydi-p-phenylene)]dipropionic acid, 4,4'-[4,4'-(oxydi-p-phenylene)]dibutyric acid, (isopropylene) Examples include dicarboxylic acids such as di-p-phenylenedioxy) dibutyric acid and bis(p-carboxyphenyl)dimethylsilane.
Examples of dicarboxylic acids containing heterocycles include 1,5-(9-oxofluorene)dicarboxylic acid, 3,4-furandicarboxylic acid, 4,5-thiazoledicarboxylic acid, 2-phenyl-4,5-thiazoledicarboxylic acid, 1,2,5-thiadiazole-3,4-dicarboxylic acid, 1,2,5-oxadiazole-3,4-dicarboxylic acid, 2,3-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 2, Examples include 5-pyridinedicarboxylic acid, 2,6-pyridinedicarboxylic acid, 3,4-pyridinedicarboxylic acid, and 3,5-pyridinedicarboxylic acid.

The various dicarboxylic acids mentioned above may have an acid dihalide or anhydride structure. These dicarboxylic acids are particularly preferably dicarboxylic acids that can provide a polyamide with a linear structure in order to maintain the orientation of liquid crystal molecules. Among these, terephthalic acid, isoterephthalic acid, 1,4-cyclohexanedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 4,4'-diphenylethanedicarboxylic acid, 4,4 '-Diphenylpropanedicarboxylic acid, 4,4'-diphenylhexafluoropropanedicarboxylic acid, 2,2-bis(phenyl)propanedicarboxylic acid, 4,4''-terphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2 , 5-pyridinedicarboxylic acid or these acid dihalides are preferably used. Some of these compounds have isomers, but a mixture containing them may also be used. They may be used in combination.The dicarboxylic acids used in the present invention are not limited to the above-mentioned exemplified compounds.

Selected from raw material diamine (also described as "diamine component"), raw material tetracarboxylic dianhydride (also described as "tetracarboxylic dianhydride component"), tetracarboxylic acid diester, diisocyanate, and dicarboxylic acid. In order to obtain polyamic acid, polyamic acid ester, polyurea, and polyamide by reaction with the components, known synthesis techniques can be used. Generally, it is a method in which a diamine component and one or more components selected from a tetracarboxylic dianhydride component, a tetracarboxylic diester, a diisocyanate, and a dicarboxylic acid are reacted in an organic solvent.

When poly(meth)acrylate is selected as the polymer β, one preferred embodiment of the poly(meth)acrylate is a polyacrylate other than the polymer α described above. For example, it is a polymer obtained by polymerizing industrially available monomers capable of radical polymerization using a common radical generator.

Specific examples of industrially available monomers capable of radical polymerization include unsaturated carboxylic acids, acrylic ester compounds, methacrylic ester compounds, maleimide compounds, acrylonitrile, maleic anhydride, styrene compounds, and vinyl compounds. It will be done.

Specific examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, maleic acid, and fumaric acid.

Examples of acrylic ester compounds include methyl acrylate, ethyl acrylate, isopropyl acrylate, benzyl acrylate, naphthyl acrylate, anthryl acrylate, anthryl methyl acrylate, phenyl acrylate, 2,2,2-trifluoroethyl acrylate, and tert-butyl acrylate. Acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 2-methyl-2-adamantyl acrylate, 2- Examples include propyl-2-adamantyl acrylate, 8-methyl-8-tricyclodecyl acrylate, and 8-ethyl-8-tricyclodecyl acrylate. Acrylate compounds having cyclic ether groups such as glycidyl acrylate, (3-methyl-3-oxetanyl) methyl acrylate, and (3-ethyl-3-oxetanyl) methyl acrylate can also be used.

Examples of methacrylic acid ester compounds include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, benzyl methacrylate, naphthyl methacrylate, anthryl methacrylate, anthryl methyl methacrylate, phenyl methacrylate, 2,2,2-trifluoroethyl methacrylate, and tert-butyl. Methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, methoxytriethylene glycol methacrylate, 2-ethoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutyl methacrylate, 2-methyl-2-adamantyl methacrylate, 2- Examples include propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecyl methacrylate, and 8-ethyl-8-tricyclodecyl methacrylate. Methacrylate compounds having a cyclic ether group such as glycidyl methacrylate, (3-methyl-3-oxetanyl) methyl methacrylate, and (3-ethyl-3-oxetanyl) methyl methacrylate can also be used.

Examples of the vinyl compound include vinyl ether, methyl vinyl ether, benzyl vinyl ether, 2-hydroxyethyl vinyl ether, phenyl vinyl ether, and propyl vinyl ether.

Examples of styrene compounds include styrene, methylstyrene, chlorostyrene, bromostyrene, and the like.

Examples of maleimide compounds include maleimide, N-methylmaleimide, N-phenylmaleimide, and N-cyclohexylmaleimide.

In addition to the industrially available monomers that can undergo radical polymerization reactions, there are also side chain polymers using monomers with a liquid crystal side chain structure (hereinafter referred to as liquid crystal side chain monomers) and photosensitive groups. It is also possible to use photosensitive monomers (hereinafter referred to as photoreactive side chain monomers).

A liquid crystalline side chain monomer is a monomer in which a polymer derived from the monomer exhibits liquid crystallinity and can form a mesogenic group at the side chain site.
More specific examples of liquid crystalline side chain monomers include hydrocarbons, radically polymerizable groups such as (meth)acrylate, itaconate, fumarate, maleate, α-methylene-γ-butyrolactone, styrene, vinyl, maleimide, and norbornene. It is preferable that the structure has a polymerizable group composed of at least one kind selected from the group consisting of a side chain having at least one kind of mesogenic group included in a liquid crystal side chain.

The liquid crystal side chain monomer is preferably a monomer in which a liquid crystal side chain selected from the following formulas (LS-1) to (LS-13) is bonded to a polymerizable group capable of radical polymerization. Examples of the radically polymerizable polymerizable group include the polymerizable group having a polymerizable unsaturated hydrocarbon group as exemplified in the explanation of the polymer α.

(In formulas (LS-1) to (LS-13), A ¹ and A ² each independently represent a single bond, -O-, -CH ₂ -, -C(=O)-O-, - OC(=O)-, -C(=O)NH-, -NHC(=O)-, -CH=CH-C(=O)O-, or -OC(=O)-CH=CH- and R ¹¹ is -NO ₂ , -CN, a halogen atom, a phenyl group, a naphthyl group, a biphenylyl group, a furanyl group, a monovalent nitrogen-containing heterocyclic group, a monovalent alicyclic hydrocarbon group having 5 to 8 carbon atoms. , represents an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms, and R ¹² is a phenyl group, a naphthyl group, a biphenylyl group, a furan-2,5-diyl group, or a monovalent nitrogen-containing heterocycle. represents a group selected from the group consisting of a group, a monovalent alicyclic hydrocarbon group having 5 to 8 carbon atoms, and a group obtained by combining these, and in R ¹¹ and R ¹² , the hydrogen atoms bonded to these are It may be substituted with -NO ₂ , -CN, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms, and R ¹³ is a hydrogen atom, -NO ₂ , -CN, - CH=C(CN) ₂ , -CH=CH-CN, halogen atom, phenyl group, naphthyl group, biphenylyl group, furan-2,5-diyl group, monovalent nitrogen-containing heterocyclic group, carbon number 5-8 Represents a monovalent alicyclic hydrocarbon group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms, and E is -C(=O)O- or -OC(=O)- , d represents an integer from 1 to 12, and k1 to k5 are each independently an integer from 0 to 2, but the sum of k1 to k5 in each formula is 2 or more, and k6 and k7 are each independently an integer of 0 to 2, but in each formula, the sum of k6 and k7 is 1 or more, m1, m2 and m3 are each independently an integer of 1 to 3, n is 0 or 1, Z ¹ and Z ² each independently represent a single bond, -C(=O)-, -CH ₂ O-, -CH=N- or -CF ₂ - (The dashed line represents the bond.)

In photoreactive side chain monomers, a photosensitive side chain is bonded to the main chain, and photoreactive side chain monomers can undergo cross-linking reactions, isomerization reactions, or photo-Fries rearrangement in response to light. It is a monomer with side chains. The structure of the photosensitive side chain is not particularly limited, but a structure that causes a crosslinking reaction or a photo-Fries rearrangement in response to light is desirable, and a structure that causes a crosslinking reaction is more desirable. In this case, even if exposed to external stress such as heat, the achieved orientation control ability can be stably maintained for a long period of time. The structure of the photosensitive side chain type acrylic polymer capable of exhibiting liquid crystallinity is not particularly limited as long as it satisfies such characteristics, but preferably has a rigid mesogenic component in the side chain structure.

The structure of the photosensitive side chain type acrylic polymer has, for example, a main chain and a side chain bonded to the main chain, and the side chain is a biphenyl group, terphenyl group, phenylcyclohexyl group, phenylbenzoate group, or azobenzene group. It has a structure that has a mesogenic component such as and a photosensitive group that is bonded to the tip of the side chain and undergoes a crosslinking reaction or isomerization reaction in response to light, or a main chain and a side chain that is bonded to it. It can have a structure having a phenylbenzoate group whose side chain also serves as a mesogen component and undergoes a photo-Fries rearrangement reaction.

More specific examples of structures of photosensitive side chain type acrylic polymers that can exhibit liquid crystallinity in a predetermined temperature range include hydrocarbons, (meth)acrylates, itaconates, fumarates, maleates, α-methylene-γ - A main chain consisting of at least one kind selected from the group consisting of radically polymerizable groups such as butyrolactone, styrene, vinyl, maleimide, norbornene, and a side consisting of at least one kind of the following formulas (31) to (35). A structure having a chain is preferable.

In the formula, Ar ₁ and Ar ₂ each independently represent a divalent organic group obtained by removing two hydrogen atoms from a benzene ring, a naphthalene ring, a pyrrole ring, a furan ring, a thiophene ring, or a pyridine ring,
One of q1 and q2 is 1 and the other is 0,
Y ₁ -Y ₂ represents CH=CH, CH=N, N=CH or CC (however, the bond between carbon and carbon is a triple bond),
S ₁ and S ₂ each independently represent a single bond, a linear or branched alkylene group having 1 to 18 carbon atoms, a cycloalkylene group having 5 to 8 carbon atoms, a phenylene group or a biphenylylene group, or a single bond, One or more selected from ether bond, ester bond, amide bond, urea bond, urethane bond, -NR- (R represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms), carbonyl group, or a combination thereof A linear or branched alkylene group having 1 to 18 carbon atoms, a cycloalkylene group having 5 to 8 carbon atoms, or phenylene, representing two or more types of bonds, or through one or more types of bonds. A structure in which 2 to 10 moieties selected from groups, biphenylylene groups, or a combination thereof are bonded, and each of Ar ₁ and Ar ₂ is a structure in which a plurality of each are connected via the bond. Good too,
R is a hydrogen atom, a hydroxy group, a mercapto group, an amino group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylamino group having 1 to 8 carbon atoms, or a dialkylamino group having 2 to 16 carbon atoms. represents the group,
The benzene ring and/or naphthalene ring in Ar ₁ , Ar ₂ , S ₁ and S ₂ are the same or different one or more selected from a halogen atom, a cyano group, a nitro group, a carboxy group, and an alkoxycarbonyl group having 2 to 11 carbon atoms. may be substituted with a substituent. In this case, the alkyl group having 1 to 10 carbon atoms in the alkoxycarbonyl group having 2 to 11 carbon atoms may be linear, branched, cyclic, or a combination thereof; The hydrogen atom may be substituted with a halogen atom.

The method for producing the polyacrylate is not particularly limited, and any industrially-used general-purpose method can be used. Specifically, it can be produced by cationic polymerization, radical polymerization, or anionic polymerization using a vinyl group of a liquid crystal side chain monomer or a photoreactive side chain monomer. Among these, radical polymerization is particularly preferred from the viewpoint of ease of reaction control.

As a polymerization initiator for radical polymerization, a known radical polymerization initiator such as AIBN (azobisisobutyronitrile) or a known compound such as a reversible addition-fragmentation chain transfer (RAFT) polymerization reagent may be used. I can do it.

The radical polymerization method is not particularly limited, and emulsion polymerization, suspension polymerization, dispersion polymerization, precipitation polymerization, bulk polymerization, solution polymerization, etc. can be used.

The organic solvent used in the polymerization reaction of the photosensitive side chain type acrylic polymer capable of exhibiting liquid crystallinity in a predetermined temperature range is not particularly limited as long as it dissolves the produced polymer. Specific examples are listed below.
N,N-dimethylformamide, N,N-diethylformamide, N,N-dibutylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dipropylacetamide, N,N-dimethylpropionamide , N,N-diethylpropionamide, 3-methoxy-N,N-dimethylpropanamide, N-methylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3- Dimethyl-2-imidazolidinone, N-methyl-ε-caprolactam, N,N-diethylacetamide, N,N-dipropylacetamide, 3-methoxy-N,N-dimethylpropanamide, N,N-diethylpropionamide , dimethyl sulfoxide, tetramethyl urea, pyridine, dimethyl sulfone, hexamethyl phosphoramide, γ-butyrolactone, isopropyl alcohol, methoxymethyl pentanol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone , methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether (butyl cellosolve), propylene glycol , propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene Glycol monoacetate monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene Glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, 1,4-dioxane , n-hexane, n-pentane, n-octane, cyclohexane, 2-ethyl-1-hexanol, benzene, xylene, toluene, ethylbenzene, isopropylbenzene, tert-butylbenzene, tetrahydrofuran, diethyl ether, cyclohexanone, ethylene carbonate, Propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3 - Methyl ethoxypropionate, ethyl 3-ethoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2 -Pentanone, 3-ethoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, propyl pyruvate, butyl pyruvate, pentyl pyruvate, hexyl pyruvate, 2-ethylhexyl pyruvate, Methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, butyl acetoacetate, pentyl acetoacetate, hexyl acetoacetate, 2-ethylhexyl acetoacetate, methyl levulinate, ethyl levulinate, propyl levulinate, butyl levulinate, pentyl levulinate , hexyl levulinate, 2-ethylhexyl levulinate, dimethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl phthalate, dimethyl maleate, diethyl malonate, diethyl succinate, diethyl glutarate, adipic acid Diethyl, diethyl phthalate, diethyl maleate, dipropyl malonate, dipropyl succinate, dipropyl glutarate, dipropyl adipate, dipropyl phthalate, dipropyl maleate, dibutyl malonate, dibutyl succinate, dibutyl glutarate, dibutyl adipate, Dibutyl phthalate, dibutyl maleate, dipentyl malonate, dipentyl succinate, dipentyl glutarate, dipentyl adipate, dipentyl phthalate, dipentyl maleate, dihexyl malonate, dihexyl succinate, dihexyl glutarate, dihexyl adipate, phthalic acid Dihexyl, dihexyl maleate, di-2-ethylhexyl malonate, 2-ethylhexyl succinate, 2-ethylhexyl glutarate, 2-ethylhexyl adipate, 2-ethylhexyl phthalate, 2-ethylhexyl maleate, etc. Can be mentioned.
These organic solvents may be used alone or in combination. Furthermore, even a solvent that does not dissolve the produced polymer may be mixed with the above-mentioned organic solvent and used as long as the produced polymer does not precipitate.
Further, in radical polymerization, oxygen in an organic solvent becomes a cause of inhibiting the polymerization reaction, so it is preferable to use an organic solvent that has been degassed to the extent possible.

The polymerization temperature during radical polymerization can be any temperature from 30 to 150°C, preferably from 50 to 100°C. In addition, the reaction can be carried out at any concentration, but if the concentration is too low, it will be difficult to obtain a high molecular weight polymer, and if the concentration is too high, the viscosity of the reaction solution will become too high, making it difficult to stir uniformly. Therefore, the monomer concentration is preferably 1 to 50% by weight, more preferably 5 to 30% by weight. The initial stage of the reaction can be carried out at a high concentration, and then an organic solvent can be added.
In the above-mentioned radical polymerization reaction, if the ratio of the radical polymerization initiator to the monomer is large, the molecular weight of the obtained polymer will be small, and if it is small, the molecular weight of the obtained polymer will be large, so the ratio of the radical initiator is The amount is preferably 0.1 to 10 mol % based on the monomer to be polymerized. Furthermore, various monomer components, solvents, initiators, etc. can be added during polymerization.

When recovering the produced polymer from the reaction solution of the photosensitive side-chain polymer capable of exhibiting liquid crystallinity obtained by the above reaction, the reaction solution is poured into a poor solvent and the polymers are removed. All you have to do is precipitate the coalescence. Examples of the poor solvent used for precipitation include methanol, acetone, hexane, heptane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, diethyl ether, methyl ethyl ether, water, and the like. The polymer precipitated in a poor solvent can be collected by filtration and then dried under normal pressure or reduced pressure, at room temperature or by heating. Further, by repeating the operation of redissolving the precipitated and recovered polymer in an organic solvent and reprecipitating and recovering it 2 to 10 times, the amount of impurities in the polymer can be reduced. Examples of the poor solvent in this case include alcohols, ketones, hydrocarbons, etc. It is preferable to use three or more types of poor solvents selected from these, since the efficiency of purification will further increase.

The molecular weight of the photosensitive side chain type acrylic polymer that can exhibit liquid crystallinity in a predetermined temperature range is determined by considering the strength of the resulting coating film, the workability during coating film formation, and the uniformity of the coating film. The weight average molecular weight measured by GPC method is preferably 2,000 to 1,000,000, more preferably 5,000 to 100,000.

(Weak anchoring liquid crystal alignment agent)
The weak anchoring liquid crystal aligning agent is used for forming the weak anchoring alignment film of a liquid crystal cell having liquid crystal and the weak anchoring alignment film.
In the liquid crystal aligning agent, the composite components other than the polymer α and the polymer β, which constitute the alignment film, may be monomers or polymers. When selecting a polymer as a composite component, a mixture of a plurality of polymers can be used. In addition, as composite polymers, polysiloxane, polyester, polyamide, polyurea, polyorganosiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly(styrene-maleic anhydride) copolymer, poly(isobutylene-maleic anhydride) ) copolymers, poly(vinyl ether-maleic anhydride) copolymers, poly(styrene-phenylmaleimide) derivatives, and poly(meth)acrylates. Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, SMA2000, SMA3000 (manufactured by Cray Valley), GSM301 (manufactured by Gifu Cerac Manufacturing Co., Ltd.), and poly(isobutylene-maleic anhydride) copolymers include Specific examples of poly(vinyl ether-maleic anhydride) copolymers include Isoban-600 (manufactured by Kuraray Co., Ltd.), and specific examples of poly(vinyl ether-maleic anhydride) copolymers include Gantrez AN-139 (methyl vinyl ether anhydride). maleic acid resin (manufactured by Ashland).
The other polymers may be used alone or in combination of two or more. The content ratio of other polymers is more preferably 0.1 to 90 parts by weight, and even more preferably 1 to 90 parts by weight, based on 100 parts by weight of the total of polymer α and polymer β.
Even when monomers are selected as a composite component, a plurality of monomers can be used in combination. In addition, it is preferable that the monomers to be composited are thermally curable such as polyfunctional (meth)acrylates, polyfunctional epoxides, and polyfunctional ethylene, and at the same time thermal acid generators, thermal base generators, thermal radical generators, etc. may be used together. The composite ratio of monomers to be composited with the polymer alloy is not particularly limited, but from the viewpoint of optical properties and processability, a preferred composite ratio is 99% by mass or less, more preferably 70% by mass or less.

Examples of the organic solvent used in the liquid crystal aligning agent include the above-mentioned specific organic solvents. These organic solvents may be used alone or in combination.

Furthermore, it is preferable to use a solvent that improves the uniformity and smoothness of the coating film by mixing it with an organic solvent that has high solubility.

Examples of solvents that improve the uniformity and smoothness of the coating film include isopropyl alcohol, methoxymethylpentanol, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, Ethyl carbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether (butyl cellosolve), propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol -tert- Butyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether , dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, Isobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, n-propyl lactate , n-butyl lactate, isoamyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3 -Ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1 -Phenoxy-2-propanol, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol , 2-ethyl-1-hexanol, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, pentyl pyruvate, hexyl pyruvate, 2-ethylhexyl pyruvate, methyl acetoacetate, ethyl acetoacetate, acetoacetic acid Propyl, butyl acetoacetate, pentyl acetoacetate, hexyl acetoacetate, 2-ethylhexyl acetoacetate, methyl levulinate, ethyl levulinate, propyl levulinate, butyl levulinate, pentyl levulinate, hexyl levulinate, 2-levulinate Ethylhexyl, dimethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl phthalate, dimethyl maleate, diethyl malonate, diethyl succinate, diethyl glutarate, diethyl adipate, diethyl phthalate, diethyl maleate, Dipropyl malonate, dipropyl succinate, dipropyl glutarate, dipropyl adipate, dipropyl phthalate, dipropyl maleate, dibutyl malonate, dibutyl succinate, dibutyl glutarate, dibutyl adipate, dibutyl phthalate, dibutyl maleate, malonic acid Dipentyl, Dipentyl succinate, Dipentyl glutarate, Dipentyl adipate, Dipentyl phthalate, Dipentyl maleate, Dihexyl malonate, Dihexyl succinate, Dihexyl glutarate, Dihexyl adipate, Dihexyl phthalate, Dihexyl maleate, Dipentyl malonate. Examples include 2-ethylhexyl, 2-ethylhexyl succinate, 2-ethylhexyl glutarate, 2-ethylhexyl adipate, 2-ethylhexyl phthalate, and 2-ethylhexyl maleate. A plurality of types of these solvents may be mixed. When using these solvents, it is preferably 5 to 80% by mass, more preferably 20 to 60% by mass of the total solvent contained in the liquid crystal aligning agent.

The weakly anchoring liquid crystal aligning agent of the present invention may additionally contain components other than the polymer component and the solvent (hereinafter also referred to as additive components). Such additive components include compounds for increasing the strength of the liquid crystal alignment film (hereinafter also referred to as crosslinking compounds), the adhesion between the liquid crystal alignment film and the substrate, and the adhesion between the liquid crystal alignment film and the sealant. Examples include adhesion aids for increasing the liquid crystal alignment film, dielectrics and conductive substances for adjusting the dielectric constant and electrical resistance of the liquid crystal alignment film.

Examples of the crosslinkable compound include a crosslinkable compound (c-1) having at least one substituent selected from an epoxy group, an oxetanyl group, an oxazoline structure, a cyclocarbonate group, a blocked isocyanate group, a hydroxy group, and an alkoxy group. , and at least one crosslinkable compound selected from the group consisting of a crosslinkable compound (c-2) having a polymerizable unsaturated group.
Preferred specific examples of the crosslinkable compounds (c-1) and (c-2) include the following compounds.
Compounds with epoxy groups include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexane Bisphenol A type epoxy such as diol diglycidyl ether, glycerin diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, Epicote 828 (manufactured by Mitsubishi Chemical Corporation) resins, bisphenol F type epoxy resins such as Epicote 807 (manufactured by Mitsubishi Chemical Corporation), hydrogenated bisphenol A type epoxy resins such as YX-8000 (manufactured by Mitsubishi Chemical Corporation), biphenyl skeleton-containing epoxy resins such as YX6954BH30 (manufactured by Mitsubishi Chemical Corporation) resin, phenol novolac type epoxy resin such as EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.), (o, m, p-) cresol novolak type epoxy resin such as EOCN-102S (manufactured by Nippon Kayaku Co., Ltd.), tetrakis (glycidyloxy) Methyl)methane, N,N,N',N'-tetraglycidyl-1,4-phenylenediamine, N,N,N',N'-tetraglycidyl-2,2'-dimethyl-4,4'-diamino biphenyl, 2,2-bis[4-(N,N-diglycidyl-4-aminophenoxy)phenyl]propane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, etc. Compounds in which a class nitrogen atom is bonded to an aromatic carbon atom; N,N,N',N'-tetraglycidyl-1,2-diaminocyclohexane, N,N,N',N'-tetraglycidyl-1,3- Diaminocyclohexane, N,N,N',N'-tetraglycidyl-1,4-diaminocyclohexane, bis(N,N-diglycidyl-4-aminocyclohexyl)methane, bis(N,N-diglycidyl-2-methyl- 4-aminocyclohexyl)methane, bis(N,N-diglycidyl-3-methyl-4-aminocyclohexyl)methane, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, 1,4-bis(N , N-diglycidylaminomethyl)cyclohexane, 1,3-bis(N,N-diglycidylaminomethyl)benzene, 1,4-bis(N,N-diglycidylaminomethyl)benzene, 1,3,5- TEPIC ( Isocyanurate compounds such as triglycidyl isocyanurate (manufactured by Nissan Chemical Co., Ltd.), compounds described in paragraph [0037] of Japanese Patent Application Publication No. 10-338880, compounds described in WO2017/170483, etc.;
Examples of compounds having an oxetanyl group include 1,4-bis{[(3-ethyl-3-oxetanyl)methoxy]methyl}benzene (alonoxetane OXT-121 (XDO)), bis[2-(3-oxetanyl)butyl] Ether (alonoxetane OXT-221 (DOX)), 1,4-bis[(3-ethyloxetan-3-yl)methoxy]benzene (HQOX), 1,3-bis[(3-ethyloxetan-3-yl) ) methoxy]benzene (RSOX), 1,2-bis[(3-ethyloxetan-3-yl)methoxy]benzene (CTOX), two described in paragraphs [0170] to [0175] of WO2011/132751. Compounds having the above oxetanyl group;
Examples of compounds having an oxazoline structure include 2,2'-bis(2-oxazoline), 2,2'-bis(4-methyl-2-oxazoline), and Epocross (trade name, manufactured by Nippon Shokubai Co., Ltd.). Polymers and oligomers having an oxazoline group such as, compounds described in paragraph [0115] of Japanese Patent Application Publication No. 2007-286597;
Examples of compounds having a cyclocarbonate group include N,N,N',N'-tetra[(2-oxo-1,3-dioxolan-4-yl)methyl]-4,4'-diaminodiphenylmethane, N,N' ,-di[(2-oxo-1,3-dioxolan-4-yl)methyl]-1,3-phenylenediamine and described in paragraphs [0025] to [0030] and [0032] of WO2011/155577. compounds, etc.;
Examples of compounds having a blocked isocyanate group include Coronate AP Stable M, Coronate 2503, 2515, 2507, 2513, 2555, Millionate MS-50 (manufactured by Tosoh Corporation), Takenate B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, B-882N (all manufactured by Mitsui Chemicals), two described in paragraphs [0046] to [0047] of Japanese Patent Application Publication No. 2014-224978 Compounds having the above protected isocyanate groups, compounds having three or more protected isocyanate groups described in paragraphs [0119] to [0120] of WO2015/141598, etc.;
As a compound having a hydroxy group and/or an alkoxy group, N,N,N',N'-tetrakis(2-hydroxyethyl)adipoamide, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane , 2,2-bis(4-hydroxy-3,5-dimethoxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)-1,1,1,3,3,3 -Hexafluoropropane, WO2015/072554, the compound described in paragraph [0058] of Japanese Patent Application Publication No. 2016-118753, the compound described in Japanese Patent Application Publication No. 2016-200798, the compound described in WO2010/074269 Compounds, etc.;
As a crosslinkable compound having a polymerizable unsaturated group, glycerin mono(meth)acrylate, glycerin di(meth)acrylate (1,2-,1,3-body mixture), glycerin tris(meth)acrylate, glycerol 1,3 - diglycerolate di(meth)acrylate, pentaerythritol tri(meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate, pentaethylene glycol mono(meth)acrylate ) acrylate, hexaethylene glycol mono(meth)acrylate, etc.

The above compounds are examples of crosslinkable compounds, and are not limited thereto. For example, components other than the above disclosed on page 53 [0105] to page 55 [0116] of WO2015/060357 can be mentioned. Moreover, two or more types of crosslinkable compounds may be used in combination.

When using a crosslinkable compound, the content of the crosslinkable compound in the liquid crystal aligning agent is preferably 0.5 to 20 parts by mass based on 100 parts by mass of the polymer component contained in the liquid crystal aligning agent. , more preferably 1 to 15 parts by mass.

Examples of the adhesion aids include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N -(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N -Ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-3-triethoxysilylpropyltriethylenetetramine, N-3-trimethoxysilylpropyltriethylenetetramine, 10 -trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3, 6-Diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-amino Propyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxy Propylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris(3-trimethoxysilylpropyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxy Examples include silane coupling agents such as silane and 3-isocyanatepropyltriethoxysilane.
When using an adhesion aid, the content of the adhesion aid in the liquid crystal aligning agent is preferably 0.1 to 30 parts by mass based on 100 parts by mass of the polymer component contained in the liquid crystal aligning agent, and more preferably Preferably it is 0.1 to 20 parts by mass.

(Strong anchoring horizontal alignment film)
It is necessary to provide a strong anchoring horizontal alignment film on a substrate opposite to the substrate provided with the weak anchoring alignment film. The strong anchoring horizontal alignment film described here is a liquid crystal alignment film that can uniformly align liquid crystals in the horizontal direction and has a sufficiently strong force to maintain the aligned liquid crystals, that is, interfacial anchoring energy.

A strong anchoring horizontal alignment film can be obtained by aligning the polyamic acid, polyimide, polyamic acid ester, polyamide, polyester, polyacrylate, etc. described above in a uniaxial direction by rubbing, photo alignment, or the like.

A strong anchoring horizontal alignment film can be obtained by combining the monomers mentioned above.

(Weak anchoring alignment film and strong anchoring horizontal alignment film)
The weakly anchoring alignment film of the present invention can be obtained by using the weakly anchoring liquid crystal alignment agent described above. For example, after applying the weakly anchoring liquid crystal aligning agent used in the present invention to a substrate, the cured film obtained by drying and baking is rubbed, irradiated with polarized light or light of a specific wavelength, etc., or irradiated with an ion beam, etc. It can be obtained by performing orientation treatment during processing.

Similarly, a strong anchoring horizontal alignment film can be obtained by applying a strong anchoring liquid crystal aligning agent to a substrate, and then subjecting the cured film obtained by drying and baking to an alignment treatment.

In the present invention, the first substrate may be a substrate having comb-teeth electrodes, and the second substrate may be a counter substrate. Further, in the present invention, the second substrate may be a substrate having comb-teeth electrodes, and the first substrate may be a counter substrate.

The substrate on which each liquid crystal alignment film is applied is not particularly limited as long as it is a highly transparent substrate, but a substrate on which a transparent electrode for driving liquid crystal is formed is preferable.

Specific examples include glass plates, polycarbonates, poly(meth)acrylates, polyethersulfones, polyarylates, polyurethanes, polysulfones, polyethers, polyetherketones, trimethylpentene, polyolefins, polyethylene terephthalate, (meth)acrylonitrile, and Examples include substrates in which transparent electrodes are formed on plastic plates such as cellulose acetate, cellulose diacetate, and cellulose acetate butyrate.

Substrates that can be used for IPS type liquid crystal display elements include electrode patterns such as standard IPS comb electrodes and PSA (Polymer-Stabilized Alignment) fishbone electrodes, as well as protrusion patterns such as MVA (Multi-domain Vertical Alignment). can.

Furthermore, in a high-performance element such as a TFT (Thin-Film-Transistor) type element, an element such as a transistor is formed between an electrode for driving a liquid crystal and a substrate.

When a transmissive type liquid crystal display element is intended, it is common to use a substrate like the one described above, but when a reflective type liquid crystal display element is intended, silicon is used for only one side of the substrate. Opaque substrates such as wafers can also be used. In this case, a material such as aluminum that reflects light can also be used for the electrodes formed on the substrate.

Application methods for weakly anchoring liquid crystal alignment agents include spin coating, printing, inkjet, spraying, and roll coating, but transfer printing is widely used industrially from the viewpoint of productivity. Therefore, it is suitably used in the present invention.

The drying process after applying the liquid crystal aligning agent is not necessarily required, but if the time from application to firing is not constant for each substrate, or if the board is not fired immediately after application, a drying process is included. is preferable. This drying may be performed as long as the solvent is removed to such an extent that the shape of the coating film is not deformed due to transportation of the substrate, etc., and the drying means is not particularly limited. Preferred conditions for the drying step include drying on a hot plate at a temperature of 40 to 150°C, more preferably 60 to 100°C, for 0.5 to 30 minutes, more preferably 1 to 5 minutes. Preferred conditions for the baking step include baking on a hot plate or hot air circulation oven at a temperature of 80 to 250°C, more preferably 100 to 230°C, for 1 to 120 minutes, more preferably 5 to 30 minutes.

The thickness of this cured film can be selected as required, but it is preferably 5 nm or more, more preferably 10 nm or more, since this improves the reliability of the liquid crystal display element. Further, it is preferable that the thickness of the cured film is preferably 300 nm or less, more preferably 150 nm or less, since the power consumption of the liquid crystal display element does not become extremely large.

As described above, a first substrate or a second substrate having a weak anchoring alignment film and a second substrate or first substrate having a strong anchoring horizontal alignment film can be obtained. Examples of methods for performing the uniaxial alignment treatment include a photoalignment method, an oblique evaporation method, rubbing, and a uniaxial alignment treatment using a magnetic field.

When performing orientation treatment by rubbing in one direction, for example, while rotating a rubbing roller around which a rubbing cloth is wound, the substrate is moved so that the rubbing cloth and the film come into contact with each other. When using a photo-alignment method, the alignment process can be performed by irradiating the entire surface of the film with polarized UV light of a specific wavelength and heating if necessary.

In the case of a substrate on which comb-teeth electrodes are formed, the direction is selected depending on the electrical properties of the liquid crystal, but when using a liquid crystal with positive dielectric anisotropy, the rubbing direction is the direction in which the comb-teeth electrodes extend. It is preferable that the direction is approximately the same as that of .

[Liquid crystal cell]
The liquid crystal cell of the present invention has a substrate (for example, a first substrate) having a weakly anchoring alignment film obtained by using the liquid crystal aligning agent of the present invention by the above method, and a known strong anchoring liquid crystal aligning film. Arranging a substrate (for example, a second substrate) so that a weak anchoring alignment film and a strong anchoring horizontal alignment film face each other, sandwiching a spacer, fixing with a sealant, and sealing by injecting liquid crystal. It is obtained by At this time, the size of the spacer used is usually 1 to 30 μm, preferably 2 to 10 μm. In addition, by making the rubbing direction of the first substrate parallel to the rubbing direction of the second substrate, it can be used for the IPS method or FFS method, and if the rubbing directions are arranged orthogonally, it can be used for the TN method. can be used.

Note that an IPS substrate, which is a comb-teeth electrode substrate used in the IPS method, includes a base material, a plurality of linear electrodes formed on the base material and arranged in a comb-teeth shape, and a plurality of linear electrodes formed on the base material. It has a liquid crystal alignment film formed so as to cover the liquid crystal alignment film.

The FFS substrate, which is a comb-teeth electrode substrate used in the FFS method, consists of a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, and an insulating film formed on the insulating film. , has a plurality of linear electrodes arranged in a comb-teeth shape, and a liquid crystal alignment film formed on an insulating film so as to cover the linear electrodes.

(Method for manufacturing liquid crystal display element)
The method of manufacturing a liquid crystal display element of the present invention includes the step of manufacturing a substrate with a weak anchoring alignment film by the method of manufacturing a substrate with a weak anchoring alignment film of the present invention.

(Liquid crystal display element)
A liquid crystal display element includes, for example, a first substrate, a second substrate disposed opposite to the first substrate, and liquid crystal filled between the first substrate and the second substrate. The liquid crystal display element comprises a first substrate or a second substrate coated with a weak anchoring liquid crystal alignment agent of the present invention and provided with a weak anchoring alignment film, and a second substrate or a second substrate provided with a strong anchoring horizontal alignment film. Fabricated using a first substrate.

The liquid crystal display element can be made into a reflective liquid crystal display element by, for example, providing a reflective electrode, a transparent electrode, a λ/4 plate, a polarizing film, a color filter layer, etc. in a liquid crystal cell according to a conventional method as necessary. Furthermore, a transmissive liquid crystal display element can be obtained by providing a backlight, a polarizing plate, a λ/4 plate, a transparent electrode, a polarizing film, a color filter layer, etc. in a conventional manner to the liquid crystal cell as required.

FIG. 1 is a schematic cross-sectional view showing an example of a horizontal electric field liquid crystal display element of the present invention, and is an example of an IPS type liquid crystal display element.

In the horizontal electric field liquid crystal display element 1 illustrated in FIG. 1, a liquid crystal 3 is sandwiched between a comb-teeth electrode substrate 2 having a liquid crystal alignment film 2c and a counter substrate 4 having a liquid crystal alignment film 4a. The comb-teeth electrode substrate 2 includes a base material 2a, a plurality of linear electrodes 2b formed on the base material 2a and arranged in a comb-teeth shape, and a plurality of linear electrodes 2b formed on the base material 2a so as to cover the linear electrodes 2b. It has a liquid crystal alignment film 2c. The counter substrate 4 has a base material 4b and a weak anchoring liquid crystal alignment film or a strong anchoring horizontal alignment film (liquid crystal alignment film 4a) formed on the base material 4b. The liquid crystal alignment film 2c is, for example, a weak anchoring alignment film or a strong anchoring horizontal alignment film of the present invention. The liquid crystal alignment films provided on the opposing substrates are each made of a combination of a strong anchoring horizontal alignment film and a weak anchoring liquid crystal alignment film.
In this horizontal electric field liquid crystal display element 1, when a voltage is applied to the linear electrodes 2b, an electric field is generated between the linear electrodes 2b as shown by lines of electric force L.

FIG. 2 is a schematic cross-sectional view showing another example of the horizontal electric field liquid crystal display element of the present invention, and is an example of an FFS type liquid crystal display element.

In the horizontal electric field liquid crystal display element 1 illustrated in FIG. 2, a liquid crystal 3 is sandwiched between a comb-teeth electrode substrate 2 having a liquid crystal alignment film 2h and a counter substrate 4 having a liquid crystal alignment film 4a. The comb-teeth electrode substrate 2 is formed on a base material 2d, a surface electrode 2e formed on the base material 2d, an insulating film 2f formed on the surface electrode 2e, and an insulating film 2f, and has a comb-like shape. It has a plurality of arranged linear electrodes 2g and a liquid crystal alignment film 2h formed on an insulating film 2f so as to cover the linear electrodes 2g. The counter substrate 4 has a base material 4b and a liquid crystal alignment film 4a formed on the base material 4b. The liquid crystal alignment film 4a is similar to the liquid crystal alignment film 4a in FIG. 1 described above. The liquid crystal alignment film 2h is similar to the liquid crystal alignment film 2c in FIG. 1 described above.
In this horizontal electric field liquid crystal display element 1, when a voltage is applied to the plane electrode 2e and the linear electrode 2g, an electric field is generated between the plane electrode 2e and the linear electrode 2g as shown by lines of electric force L.

The present invention will be specifically explained below with reference to Examples, but the present invention should not be construed as being limited to these Examples. The abbreviations of the compounds and the measurement methods for each property are as follows.

(Radical polymerizable monomer compatible with liquid crystal)

(Radical polymerizable monomer that becomes insolubilized in liquid crystal by heating etc.)

Me represents a methyl group.

(Photo-alignable radical polymerization monomer)

(RAFT agent)

(RAFT removal agent)

(Chain transfer agent)

Me represents a methyl group.

(Thermal polymerization initiator)

(Diamine)

(Tetracarboxylic dianhydride)

(Additive)

(solvent)
THF: Tetrahydrofuran NMP: N-methyl-2-pyrrolidone BCS: Ethylene glycol monobutyl ether BCA: Ethylene glycol monobutyl ether acetate PGMEA: Propylene glycol monomethyl ether acetate

(Viscosity measurement)
The viscosity of polyamic acid solutions, etc., was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.), sample volume 1.1 mL (milliliter), cone rotor TE-1 (1° 34', R24), temperature 25 Measured at ℃.

(Measurement of molecular weight)
The molecular weight of the polyimide precursor and the synthesized polymers other than polyimide was measured using a cold gel permeation chromatography (GPC) device (CBM-20A) (manufactured by Shimadzu Corporation) and a series column (Shodex (registered trademark) KF-804L and KF-803L). ) (manufactured by Showa Denko) as follows.
Column temperature: 40℃
Eluent: Tetrahydrofuran Flow rate: 1.0 mL/min Standard sample for creating a calibration curve: Standard polystyrene (molecular weight: 197,000, 55,100, 12,800, 3,950, 1,260) (manufactured by Tosoh Corporation)

The molecular weight of the polyimide precursor and polyimide was determined using a room-temperature gel permeation chromatography (GPC) device (GPC-101) (manufactured by Showa Denko) and a column (GPC KD-803 and GPC KD-805 in series) (manufactured by Showa Denko). The measurement was performed using the following method.
Column temperature: 50℃
Eluent: N,N-dimethylformamide (as additives, lithium bromide monohydrate (LiBr.H ₂ O) is 30 mmol/L (liter), phosphoric acid/anhydrous crystal (o-phosphoric acid) is 30 mmol/ L, tetrahydrofuran (THF) 10 mL/L)
Flow rate: 1.0 mL/min Standard sample for creating a calibration curve: TSK standard polyethylene oxide (molecular weight: approx. 900,000, 150,000, 100,000 and 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight: approx. 12,000, 4,000 and 1,000) (manufactured by Polymer Laboratory).

(Measurement of imidization rate)
Put 20 mg of polyimide powder into an NMR sample tube (Kusano Scientific Co., Ltd. NMR sampling tube standard Φ5), and add 1.0 mL of deuterated dimethyl sulfoxide (DMSO-d ₆ , 0.05 mass% tetramethylsilane (TMS) mixture). It was added and completely dissolved using ultrasound. This solution was subjected to proton NMR measurement at 500 MHz using a Fourier transform superconducting nuclear magnetic resonance apparatus (FT-NMR) "AVANCE III" (manufactured by BRUKER).
The imidization rate is determined by using a proton derived from a structure that does not change before and after imidization as a reference proton, and by calculating the peak integrated value of this proton and the proton peak derived from the NH group of amic acid that appears around 9.5 to 10.0 ppm. It was calculated using the following formula using the integrated value. In the formula, X is the integrated value of the proton peak derived from the NH group of the amic acid, Y is the integrated value of the reference proton peak, and A is the integrated value of the proton peak derived from the NH group of the amic acid, and A is the integrated value of the amic acid in the case of polyamic acid (imidization rate is 0%). This is the ratio of the number of standard protons to one proton of the NH group.
Imidization rate (%) = (1-A・X/Y)×100

<Synthesis of homopolymer>
(Synthesis example 1-1)
A-1 (10.0 g, 58.7 mmol), R-3 (294 mg, 0.729 mmol), and AIBN (59.9 mg, 0.365 mmol) were placed in a 50 ml eggplant flask equipped with a stirrer and a nitrogen introduction tube. After weighing and adding THF (10.4 g), stirring at room temperature to dissolve, the system was purged with nitrogen, and heated and stirred in an oil bath set at 60° C. for 24 hours. After heating and stirring, the reaction solution was gently poured into the mixture while stirring methanol (30 g) to precipitate a solid, and the mixture was stirred for 30 minutes. This precipitate was collected by filtration, slurry washing was performed twice with methanol (30 g) for 30 minutes, and the solid was vacuum-dried at 50° C. to obtain homopolymer mCTA-1. Number average molecular weight (Mn): 11,400, weight average molecular weight (Mw): 13,000.

(Synthesis examples 1-2 to 1-14)
By carrying out the same procedure as Synthesis Example 1-1 except that the type of raw material (monomer) used, the type of catalyst, and the amount charged were replaced with those shown in Table 1 below, the homopolymer shown in Table 1 below was prepared. Obtained.

<Synthesis of homopolymer using terminal group conversion>
(Synthesis example 1-15)
The mCTA-1 (6.00 g, 0.526 mmol) obtained in Synthesis Example 1-1 was weighed into a 50 ml eggplant flask equipped with a stirring bar and a nitrogen inlet tube, THF (6.32 g) was added, and the mixture was stirred at room temperature. Stir to dissolve. The atmosphere in the system was purged with nitrogen, AM-1 (316 mg, 5.26 mmol) was added, and the mixture was stirred at room temperature for 6 hours. After confirming that the reaction solution became transparent, methanol (40 g) was gently poured into the reaction solution while stirring to precipitate a solid, and the mixture was stirred for 30 minutes. This precipitate was collected by filtration, slurry washing was performed twice with methanol (40 g) for 30 minutes, and the solid was vacuum-dried at 50° C. to obtain homopolymer mTT-1. Mn: 11,500, Mw: 12,900.

<Synthesis of block copolymer using RAFT polymerization>
(Synthesis example 2-1)
mCTA-1 (3.81 g, 0.334 mmol), B-1 (6.00 g, 23.9 mmol), and AIBN (27.4 mg, 0.167 mmol) were placed in a 50 ml eggplant flask equipped with a stirrer and a nitrogen inlet tube. ) was added, THF (9.84 g) was added, and the mixture was stirred and dissolved at room temperature. The system was purged with nitrogen, and the mixture was heated and stirred in an oil bath set at 60° C. for 24 hours. After heating and stirring, the reaction solution was gently poured into the mixture while stirring methanol (40 g) to precipitate a solid, and the mixture was stirred for 30 minutes. This precipitate was collected by filtration, slurry washed again with methanol (40 g) for 30 minutes twice in total, and the solid was vacuum-dried at 50° C. to obtain block copolymer BCP-1. Mn: 24,200, Mw: 30,000.

(Synthesis examples 2-2 to 2-6)
The block copolymer (BCP-2 ~BCP-6) was obtained.

<Synthesis of macromonomer>
(Synthesis example 3-1)
A-7 (10.0 g, 78.0 mmol), S-4 (0.216 g, 2.34 mmol) and AIBN (0.128 g, 0.780 mmol) were placed in a 50 mL eggplant flask equipped with a stirrer and a nitrogen inlet tube. ) was added, THF (10.3 g) was added, and the mixture was stirred and dissolved at room temperature. The system was purged with nitrogen, and the mixture was heated and stirred in an oil bath set at 60° C. for 12 hours. After heating and stirring, the reaction solution was gently poured into the mixture while stirring cold methanol (30.0 g) to precipitate a solid, and the mixture was stirred for 30 minutes. This precipitate was collected by filtration, slurry washing was performed twice for 30 minutes with cold methanol (30 g), and the solid was vacuum-dried at 50° C. to obtain a prepolymer. Mn: 6,000, Mw: 9,900.
In a 100 mL eggplant flask equipped with a stirrer and a nitrogen inlet tube, the prepolymer (10.0 g, 1.67 mmol) synthesized by the above method, B-4 (0.830 g, 5.83 mmol), and Hydroquinone (8. N,N-dimethyllaurylamine (2.0 mg) and Xylene (20.0 g) were added, stirred at room temperature to dissolve, and then heated and stirred in an oil bath set at 140° C. for 6 hours. After heating and stirring, the reaction solution was gently poured into the mixture while stirring methanol (50 g) to precipitate a solid, and the mixture was stirred for 30 minutes. This precipitate was collected by filtration, slurry washing was performed twice with methanol (50 g) for 30 minutes, and the solid was vacuum-dried at 50° C. to obtain macromonomer (MA-1). Mn: 6,100, Mw: 9,900.

<Synthesis of graft copolymer>
(Synthesis example 3-2)
MA-1 (1.00 g, 0.167 mmol), B-2 (4.10 g, 16.5 mmol), and AIBN (82.1 mg, 0.500 mmol) were placed in a 100 mL eggplant flask equipped with a stirrer and a nitrogen introduction tube. ) was added, THF (7.77 g) was added, and the mixture was stirred and dissolved at room temperature.The system was purged with nitrogen, and the mixture was heated and stirred in an oil bath set at 60°C for 12 hours. After heating and stirring, the reaction solution was gently poured into the mixture while stirring methanol (40 g) to precipitate a solid, and the mixture was stirred for 30 minutes. This precipitate was separated by filtration, slurry washing was performed twice with methanol (40 g) for 30 minutes, and the solid was vacuum-dried at 50° C. to obtain a graft copolymer (GP-1). Mn: 92,200, Mw: 196,600.

<Synthesis of bottle brush polymer>
(Synthesis example 4-1)
In a 100 ml eggplant flask equipped with a stirrer and a nitrogen inlet tube, add 2-((2-bromo-2-methylpropanoyl)oxy)ethyl methacrylate (5.00 g, 17.91 mmol), B-7 (0.078 g, 0 .60 mmol), R-3 (0.72 g, 1.80 mmol), and AIBN (0.09 g, 0.54 mmol) were added, THF (10.2 g) was added, and after stirring and dissolving at room temperature, the system The atmosphere inside the reactor was replaced with nitrogen, and the reactor was heated and stirred for 12 hours in an oil bath set at 60°C. After heating and stirring, the reaction solution was gently poured into the mixture while stirring methanol (50.0 g) to precipitate a solid, and the mixture was stirred for 30 minutes. This precipitate was collected by filtration, slurry washing was performed twice with methanol (50.0 g) for 30 minutes, and the solid was vacuum-dried at 50° C. to obtain macromonomer (MA-2). Mn: 45,300, Mw: 68,000.
Macromonomer synthesized by the above method (MA-2: 2.00 g, 0.03 mmol), B-2 (0.43 g, 1.76 mmol), A-1 (3.00g, 17.62mmol), ethyl 2-bromoisobutyrate (0.012g, 0.06mmol), CuBr (0.03g, 0.19mmol), N, N, N', N'', N ''-Pentamethyldiethylenetriamine (0.043 g, 0.25 mmol) and Anisole (7.5 g) were added, stirred at room temperature to dissolve, then frozen and degassed three times, and left in an oil bath set at 90°C for 6 hours. The mixture was heated and stirred. After heating and stirring, the reaction solution was gently poured into the mixture while stirring methanol (50.0 g) to precipitate a solid, and the mixture was stirred for 30 minutes. This precipitate was collected by filtration, slurry washing was performed twice with methanol (50.0 g) for 30 minutes, and the solid was vacuum-dried at 50°C to obtain bottle brush polymer (BBP-1). . Mn: 203,000, Mw: 384,000.

<Synthesis of polyamic acid/polyimide>
(Synthesis example 5-1)
Add DA-1 (0.584 g, 5.40 mmol), DA-2 (1.98 g, 8.10 mmol), and DA-3 (2.60 g) to a 100 mL four-necked flask equipped with a mechanical stirrer and nitrogen introduction tube. , 8.10 mmol) and DA-4 (1.84 g, 5.40 mmol), added NMP (93.73 g), stirred under nitrogen atmosphere to dissolve, and then heated to below 10°C in an ice bath. By adding TC-1 (5.63 g, 25.1 mmol) and reacting at room temperature under nitrogen atmosphere for 18 hours, polyamic acid (PAA-1) with a viscosity of about 200 mPa・s and a solid content concentration of 12% by mass was obtained. ) was obtained. The molecular weights of this polyamic acid were Mn: 12,600 and Mw: 35,200.

(Synthesis example 5-2)
Weigh the solution (40.0 g) of polyamic acid (PAA-1) obtained above into a 300 mL eggplant flask equipped with a stir bar and nitrogen inlet tube, add NMP (74.3 g), and stir for a while at room temperature. After that, acetic anhydride (5.61 g: 55.0 mmol) and pyridine (2.90 g, 36.7 mmol) were added, stirred at room temperature under nitrogen atmosphere for 30 minutes, and then reacted at 50°C under nitrogen atmosphere for 3 hours. . After the reaction was completed, the reaction solution was slowly poured into methanol (500 mL) cooled to below 10° C. with stirring to precipitate a solid, and the mixture was stirred for 10 minutes. This precipitate was separated by filtration, slurry washed twice with methanol (200 mL) for 30 minutes, and the solid was vacuum-dried at 80°C to obtain the desired polyimide powder (SPI-1) (7.04 g). , yield 88%). The imidization rate of this polyimide was 66%, the molecular weight was Mn: 12,200, and Mw: 36,600.

(Synthesis example 5-3)
DA-5 (4.83 g, 16.2 mmol) and DA-6 (1.62 g, 10.8 mmol) were weighed into a 100 mL four-necked flask equipped with a mechanical stirrer and a nitrogen introduction tube, and NMP (89 mmol) was weighed out. 1g) was added and dissolved by stirring under a nitrogen atmosphere, then TC-2 (5.69g: 25.4mmol) was added while keeping the temperature below 10°C in an ice bath, and the reaction was carried out at room temperature for 18 hours. A solution of polyamic acid (PAA-2) with a viscosity of about 600 mPa·s and a solid content concentration of 12% by mass was obtained. The molecular weights of this polyamic acid were Mn: 17,200 and Mw: 48,200.

(Synthesis example 5-4)
DA-7 (4.30 g, 21.6 mmol) and DA-8 (1.07 g, 5.40 mmol) were weighed into a 100 mL four-necked flask equipped with a mechanical stirrer and a nitrogen introduction tube, and NMP (81.6 mmol) was weighed out. 1g) was added and dissolved by stirring under a nitrogen atmosphere, then TC-2 (5.69g, 25.4mmol) was added while keeping the temperature below 10°C in an ice bath, and the reaction was carried out at room temperature for 18 hours. A solution of polyamic acid (PAA-3) having a viscosity of about 720 mPa·s and a solid content concentration of 12% by mass was obtained. The molecular weights of this polyamic acid were Mn: 14,000 and Mw: 38,600.

Table 3 shows the contents of the polyamic acid and polyimide synthesized above.

<Preparation of weak anchoring liquid crystal alignment agent>
(Preparation example 1)
Weigh out 0.0120 g of BCP-1 obtained in Synthesis Example 2-1 and 9.90 g of the PAA-1 solution obtained in Synthesis Example 5-1 into a 30 mL vial equipped with a stirrer, By adding 2.09 g of NMP and 8.0 g of BCA and stirring at room temperature for 1 hour, BCP-1:PAA-1:NMP:BCA=0.06:5.94:54:40 (mass ratio) A weakly anchoring liquid crystal aligning agent (WAS-1) was obtained.

(Preparation Examples 2 to 25)
The weak anchoring liquid crystal aligning agent (WAS-2) shown in Table 4 below was prepared in the same manner as Preparation Example 1 except that the type and amount of the polymer used were replaced with those shown in Table 4 below. ～(WAS-25) was obtained.

Note that BCP-1 to BCP-6 are components of Polymer A that exhibit weak anchoring properties.
GP-1 is a component of Polymer B that exhibits weak anchoring properties.
mCTA-7 to mCTA-10, mTT-1, and mTr-1 to mTr-3 are components of polymer C that exhibit weak anchoring properties.
BBP-1 is a polymer other than polymers A, B, and C, and is a component that exhibits weak anchoring properties.
PAA-1 to PAA-3 and SPI-1 correspond to polymer β.

(Production of liquid crystal display element)
Below, a method for producing a liquid crystal cell for evaluating liquid crystal alignment and electro-optic response will be shown. First, a substrate with electrodes was prepared. The substrate used was an alkali-free glass substrate measuring 30 mm x 35 mm and having a thickness of 0.7 mm. An ITO (INDIUM-TIN-OXIDE) electrode is formed on the substrate with a comb-shaped pattern with an electrode width of 3 μm, an electrode spacing of 6 μm, and an angle of 10° with respect to the long side of the substrate. and formed pixels. The size of each pixel was 10 mm in length and about 5 mm in width. Hereinafter, it will be referred to as an IPS board.
Next, the weak anchoring liquid crystal alignment agents (WAS-1 to WAS-23) obtained by the above method and the liquid crystal alignment agents for horizontal alignment (SE-6414, NRB-U973 (manufactured by Nissan Chemical Co., Ltd.)) were respectively applied. After filtering with a filter with a pore size of 1.0 mm, the prepared IPS substrate and a glass substrate (hereinafter referred to as Coating and film formation was performed on the opposite substrate (referred to as the counter substrate) using a spin coating method. Next, it was dried on a hot plate at 80° C. for 2 minutes and then baked at 230° C. for 30 minutes to obtain a coating film with a thickness of 100 nm. The coating film on the IPS substrate was oriented in the direction along the comb-toothed direction, and the coating film on the counter substrate was oriented in the direction perpendicular to the comb-teeth electrodes. In the alignment treatment, a rubbing method was used in SE-6414, and a photo alignment method was used in NRB-U973. Furthermore, in WAS-1 to WAS-23, the liquid crystal cells shown in Examples were subjected to alignment treatment, while the liquid crystal cells shown in Comparative Examples (Comparative Examples 1 to 5, 7 to 11) were not subjected to alignment treatment. In the rubbing method, a rubbing device manufactured by Iinuma Gauge Co., Ltd., a rubbing cloth (YA-20R) manufactured by Yoshikawa Kako Co., Ltd., a rubbing roller (diameter 10.0 cm), a stage feed rate of 30 mm/s, a roller rotation speed of 700 rpm, and a pushing pressure of 0.3 mm were used. I went. In the photo-alignment method, a UV exposure device manufactured by Ushio Inc. was used to irradiate linearly polarized UV with an extinction ratio of about 26:1 so that the irradiation amount was 300 mJ/cm ² based on a wavelength of 254 nm. Thereafter, orientation treatment was performed by heating at 230° C. for 30 minutes.
Then, using the above two types of substrates, combine them in the combinations shown in Tables 6 and 7 below so that their orientation directions are parallel, and seal the periphery leaving the liquid crystal injection port (sealant: XN -1500T (manufactured by Mitsui Chemicals, Inc.)) at 150° C. for 60 minutes to harden the sealant and produce empty cells with a cell gap of about 3.0 μm. After liquid crystal (MLC-3019 (manufactured by Merck)) was injected into this empty cell under vacuum at room temperature, the injection port was sealed to obtain an antiparallel-aligned liquid crystal cell.
The obtained liquid crystal cell constitutes an IPS liquid crystal display element. Thereafter, the obtained liquid crystal cell was heat-treated at 120° C. for 10 minutes to obtain a liquid crystal display element.

(Evaluation of initial orientation)
Using a polarizing microscope, the polarizing plates were set to crossed nicols, the brightness of the liquid crystal cell was fixed at its lowest, and the liquid crystal cell was rotated 1° from there to observe the alignment state of the liquid crystal. If no or very slight alignment defects such as unevenness or domains are observed, it is defined as "good", and if alignment defects such as unevenness or domains are clearly observed, it is defined as "poor" and evaluated. Ta.

(Measurement of VT curve and evaluation of drive threshold voltage, maximum brightness voltage, and transmittance)
Set the white LED backlight and brightness meter so that the optical axes are aligned, set the liquid crystal cell (liquid crystal display element) with a polarizing plate attached so that the brightness is the lowest, and apply a voltage up to 8V at 1V intervals. The VT curve was measured by applying the voltage and measuring the brightness at the voltage. A voltage was applied from a state where no voltage was applied, and the voltage value (Vth) at 10% of the maximum transmitted brightness was estimated. The value of the voltage (Vmax) at which the brightness becomes maximum was estimated from the obtained VT curve. In addition, the maximum transmittance (Tmax) was estimated by setting the parallel Nicol transmission brightness as 100% through a liquid crystal cell with no voltage applied, and comparing the maximum transmission brightness in the VT curve.

(Measurement of response time (Ton, Toff))
Using the device used to measure the VT curve above, connect the luminance meter to the oscilloscope, and measure the response speed (Ton) when applying the voltage that produces the maximum luminance and the response speed (Toff) when the voltage is returned to 0V. ) was measured.

(Measurement of azimuthal anchoring strength (A ₂ ))
For the azimuthal anchoring strength A ₂ and _SA of the strong anchoring horizontal alignment films NRB-U973 and SE-6414, values separately measured by a torque balance method were used. The azimuthal anchoring strength A2 _{, WA} of the weak anchoring alignment film is calculated using the following formulas (eq2) and (eq3) using the driving threshold voltage (Vth) obtained from the VT curve measurement of the liquid crystal cell prepared above. Calculated from. Note that a case where the azimuthal anchoring strength is smaller than 1.0×10 ⁻⁴ [J/m ² ] is considered a weak anchoring alignment film, and a case where the azimuthal anchoring strength is larger than 1.0×10 ⁻⁴ [J/m ² ] is considered a weak anchoring alignment film. is a strong anchoring horizontal alignment film.

Here, V _th,SA represents the drive threshold voltage of the strong anchoring liquid crystal cell, V _th,WA represents the drive threshold voltage of the weak anchoring liquid crystal cell, l is the distance between the comb-teeth electrodes, d is the cell gap, and K ₂ is the twist elastic constant of the liquid crystal, ε ₀ is the dielectric constant of the liquid crystal in vacuum, and Δε is the dielectric constant anisotropy of the liquid crystal.
Since the above formula eq3 is originally a calculation formula when weak anchoring alignment films are used for both substrates, it is not possible to accurately calculate the azimuthal anchoring strength of the weak anchoring alignment film, but the azimuth angle anchoring strength of the weak anchoring alignment film cannot be calculated. It is used as an approximate value of angular anchoring strength.

<Evaluation of cell characteristics using photo-alignment>
(Evaluation results of weak anchoring IPS characteristics)
Table 5 shows the details of the examples and the evaluation results. Table 5 also shows the measurement results of the azimuthal anchoring strength (A ₂ ) of the liquid crystal alignment film on the IPS substrate side.
In Examples 1 to 23, both the IPS substrate and the counter substrate were subjected to photoalignment treatment.
In Comparative Examples 1 to 6, only the opposing substrate was subjected to photoalignment treatment.

In Examples 1 to 22, a liquid crystal alignment agent containing the polymer alloy of the present invention was formed on an IPS substrate, a photo-alignment film was formed on an opposing substrate, and both substrates were subjected to photo-alignment treatment. In Example 23, a liquid crystal aligning agent containing the polymer alloy of the present invention was formed on an opposing substrate, a photo-alignment film was formed on an IPS substrate, and both substrates were subjected to photo-alignment treatment, and Comparative Examples 1 to 23 In No. 5, a liquid crystal aligning agent containing a polymer alloy was formed on an IPS substrate, a photo-alignment film was formed on a counter substrate, and only the counter substrate was subjected to photo-alignment treatment.
In all of Examples 1 to 23, the transmittance was improved, the driving voltage was lowered, and the azimuthal anchoring energy was approximately 1.2×10 ⁻⁵ (J/m ² ). From this, it can be seen that weak anchoring properties are expressed even when the polymer alloy of the present invention is used and subjected to photo-alignment treatment.

From Examples 1, 9, 13, 16 and Comparative Examples 1 to 4, the response speed at voltage OFF (Toff ) has become faster by about 20 to 30 ms. This is considered to be because both a weak anchoring region and a strong anchoring region can be formed on the weak anchoring alignment film due to the following two phenomena.
・When a liquid crystal aligning agent is applied on a substrate, fine phase separation is induced in the polymer alloy consisting of polymer α and polymer β, which have significantly different physical properties (coefficient of thermal expansion and polarity), and the surface of the weakly anchored alignment film Phenomenon in which polymer α and polymer β are segmented into sea-island shapes ・Phenomenon in which only polymer β becomes uniaxially oriented by photo-alignment treatment

The azimuthal anchoring strengths of Examples 1 to 22 are larger than those of Comparative Examples 1 to 5, indicating that strong anchoring regions and weak anchoring regions are segmented on the weak anchoring alignment film. It is suggested that there is.

From Examples 1 to 3, the higher the proportion of polymer α in the polymer alloy, the higher the threshold voltage, the lower the maximum transmittance, the slower the response speed when the voltage is off, and the lower the azimuthal anchoring strength. decreased. This is because the ratio of the polymer α occupying the surface of the weak anchoring alignment film has increased, and indicates that the weak anchoring property can be controlled by controlling the ratio of the polymer α and the polymer β.

The polymer α contained in the polymer alloy may be polymer A (Examples 1 to 8), polymer B (Example 17), or polymer C (Examples 9 to 16). Also, even with weak anchoring components other than Polymers A to C (Example 18), the response speed (T _off ) when the voltage was turned off was increased by the photoalignment treatment. Due to its molecular design, any weak anchoring component is hydrophobic, flexible, and has a low Tg, so it phase separates well from the rigid and highly polar polymer β, making it an ideal weak anchoring agent. It is thought that a strong anchoring region and a strong anchoring region can be formed.

The polymer α contained in the polymer alloy of the present invention exhibits weak anchoring properties by forming a phase solution layer with the liquid crystal in the liquid crystal element. The components are not limited to the structure of polymerizable groups or polymerizable monomers as long as they are polymers that are compatible with the liquid crystal. The present applicant has proposed a radically polymerizable monomer that is contained in a liquid crystal composition that can stably produce a weakly anchoring horizontal electric field liquid crystal display element without generating a pretilt angle, and that contributes to the occurrence of weak anchoring. As radically polymerizable monomers, we discovered a compound represented by formula (2), a compound represented by formula (3), a compound represented by formula (5), and a compound represented by formula (7), and filed an application. These applications and The contents of the publications are incorporated herein to the same extent as if expressly set forth in their entirety.) By using these monomers, good weak anchoring properties can be easily achieved. From this, it can be said that the use of these monomers is appropriate.

From Examples 1 and 19 to 22, polyamic acids, polyamic acid esters, polyimides, poly(meth)acrylic esters, etc., which have photoalignment properties are preferable as the polymer β, but polymers α and the like which have photoalignment properties are preferable. The material is not particularly limited as long as it can induce phase separation. Further, a new polymer may be contained as a third component other than the polymer α and the polymer β, and the third component may or may not have photoalignment property. . It is predicted that by containing the third component, the film resistance, seal adhesion, and mechanical strength of the weakly anchored alignment film can be controlled.

From Examples 1 and 23, higher transmittance was obtained by providing a weak anchoring alignment film on the opposing substrate side. This suggests that by providing a weak anchoring alignment film on the opposing substrate side, a higher phase difference change can be obtained before and after driving the liquid crystal, and the effective film thickness of the liquid crystal that can be driven is expanded. caused by. From this, in order to obtain high transmittance, the liquid crystal or cell gap is usually designed so that the product of the birefringence difference (Δn) of the liquid crystal and the cell gap (D) is approximately 300 nm. Since high transmittance can be achieved even at a wavelength of 300 nm or less, it is possible to achieve even faster response, and it can be seen that it is also effective in improving burn-in and contrast.

<Evaluation of cell characteristics using rubbing orientation>
(Evaluation results of weak anchoring IPS characteristics)
Table 6 shows the details of the examples and the evaluation results. Table 6 also shows the measurement results of the azimuthal anchoring strength (A ₂ ) of the liquid crystal alignment film on the IPS substrate side.
In Examples 24 to 46, rubbing alignment treatment was performed on both the IPS substrate and the counter substrate.
In Comparative Examples 7 to 12, only the opposing substrate was subjected to rubbing alignment treatment.

In Examples 24 to 45, a liquid crystal aligning agent containing the polymer alloy of the present invention was formed on an IPS substrate, a rubbing alignment film was formed on a counter substrate, and both substrates were subjected to rubbing alignment treatment. In Example 46, a liquid crystal aligning agent containing the polymer alloy of the present invention was formed on a counter substrate, a rubbing alignment film was formed on an IPS substrate, and both substrates were subjected to rubbing alignment treatment. In No. 11, a liquid crystal aligning agent containing a polymer alloy was formed on an IPS substrate, a rubbing alignment film was formed on a counter substrate, and the rubbing alignment treatment was performed only on the counter substrate.
In all of Examples 24 to 46, the transmittance was improved, the driving voltage was lowered, and the azimuthal anchoring energy was approximately 1.2×10 ⁻⁵ (J/m ² ). From this, it can be seen that weak anchoring properties are expressed even when the polymer alloy of the present invention is used and subjected to rubbing orientation treatment.

From Examples 24, 32, 36, and 39, and Comparative Examples 7 to 10, it is clear that the response speed when the voltage is turned off (Toff ) has become faster by about 20 to 30 ms. This is considered to be because, similarly to the above, both the weak anchoring region and the strong anchoring region can be formed on the weak anchoring alignment film due to the following two phenomena.
・When a liquid crystal aligning agent is applied on a substrate, fine phase separation is induced in the polymer alloy consisting of polymer α and polymer β, which have significantly different physical properties (coefficient of thermal expansion and polarity), and the surface of the weakly anchored alignment film A phenomenon in which polymer α and polymer β are segmented into sea-island shapes. - A phenomenon in which only polymer β becomes uniaxially oriented by applying rubbing orientation treatment. In addition, when performing rubbing orientation treatment, the weak anchoring component is destroyed. It must be done in a range of strength that is not

The azimuthal anchoring strengths of Examples 24 to 45 are larger than those of Comparative Examples 7 to 10, indicating that strong anchoring regions and weak anchoring regions are segmented on the weak anchoring alignment film. It is suggested that there is.

From Examples 24 to 26, the higher the proportion of polymer α in the polymer alloy, the higher the threshold voltage, the lower the maximum transmittance, the slower the response speed when the voltage is off, and the lower the azimuthal anchoring strength. decreased. This is because the ratio of the polymer α occupying the surface of the weak anchoring alignment film has increased, and indicates that the weak anchoring property can be controlled by controlling the ratio of the polymer α and the polymer β.

From Examples 24 and 42 to 45, polyamic acid, polyamic acid ester, polyimide, poly(meth)acrylic acid ester, etc., which have rubbing orientation as the polymer β, are preferable, but have uniaxial orientation due to rubbing orientation treatment, The material is not particularly limited as long as it can induce phase separation with the polymer α. Further, a new polymer may be contained as a third component other than polymer α and polymer β, and the third component may or may not have uniaxial orientation. good.

From Examples 23 and 46, higher transmittance was obtained by providing a weak anchoring alignment film on the opposing substrate side. This suggests that by providing a weak anchoring alignment film on the opposing substrate side, a higher phase difference change can be obtained before and after driving the liquid crystal, and the effective film thickness of the liquid crystal that can be driven is expanded. caused by. From this, in order to obtain high transmittance, the liquid crystal or cell gap is usually designed so that the product of the birefringence difference (Δn) of the liquid crystal and the cell gap (D) is approximately 300 nm. Since high transmittance can be achieved even at a wavelength of 300 nm or less, it is possible to achieve even faster response, and it can be seen that it is also effective in improving burn-in and contrast.

(Preparation of adhesive evaluation sample)
The liquid crystal alignment agents obtained in Preparation Examples 1, 9, 13, 16-18, and 23-25 were each filtered through a filter with a pore size of 1.0 μm, and then spin-coated onto a glass substrate with a transparent electrode, and heated at 80°C. After drying on a hot plate for 2 minutes, it was baked at 230° C. for 20 minutes to obtain a coating film with a thickness of 100 nm. Further, in the same manner as in the above method, NRB-U973 was formed on all opposing substrates. The two obtained substrates were each prepared, and after scattering bead spacers with a diameter of 4 μm on the liquid crystal alignment film surface of one substrate, a sealing agent (XN-1500T manufactured by Mitsui Chemicals, Inc.) was dropped. At that time, the amount of the sealant dropped was adjusted so that the diameter of the sealant after bonding was about 3 mm. Next, the substrates were bonded with their film surfaces facing each other so that the overlapping width of the substrates was 1 cm. After fixing the bonded substrates together with clips, they were thermally cured at 120° C. for 1 hour to prepare samples for adhesive evaluation.

(Measurement of adhesive strength)
After fixing the edge portions of the upper and lower substrates using a tabletop precision universal testing machine AGS-X 500N manufactured by Shimadzu Corporation, press the prepared sample from the top of the center of the substrate to measure the pressure (N) when peeling. was measured. Note that the adhesive force (also referred to as seal peel strength or seal adhesion) was evaluated using the pressure (N) when the measured diameter of the sealant was standardized to 3.0 mm. The results are shown in Table 7.

Table 7 below lists the presence or absence of alignment treatment and the type of alignment treatment for the substrate coated with the liquid crystal alignment agent produced in the preparation example. Note that the substrate on which NRB-U973 was formed was not subjected to alignment treatment (photoalignment treatment).

It was found that the polymer alloys of the present invention that were subjected to orientation treatment (Examples 47 to 52) exhibited higher seal peel strength than those that were not subjected to orientation treatment (Comparative Examples 13 to 18). This is presumed to be because mass transfer is induced in the weakly anchored liquid crystal alignment film during the alignment process, and the weakly anchored region is slightly reduced.

According to the present invention, a stable weak anchoring film can be manufactured using an extremely simple method, the response speed when the voltage is turned off can be increased, and the adhesion with the seal can be improved, so that weak anchoring IPS can be used in a wide range of applications. In addition, it is possible to reduce the process load and improve the yield in actual industrialization. Furthermore, by using the material and method of the present invention, while suppressing the occurrence of pre-tilt angles associated with narrowing cell gaps, compared to conventional technology, faster response when voltage is turned off, less burn-in, and higher backlash in low-temperature environments. Since light transmittance and low voltage driving can be realized, it is possible to provide a material and a horizontal electric field liquid crystal display element that can stably exhibit excellent characteristics.

1 Horizontal electric field liquid crystal display element 2 Comb tooth electrode substrate

2a Base material

2b Linear electrode 2c Liquid crystal alignment film 2d Base material 2e Plane electrode 2f Insulating film 2g Linear electrode 2h Liquid crystal alignment film 3 Liquid crystal 4 Counter substrate 4a Liquid crystal alignment film 4b Base Material L Electric lines of force

Claims

A method for manufacturing a substrate with a weak anchoring alignment film used for manufacturing a liquid crystal cell having a liquid crystal and a weak anchoring alignment film, the method comprising:
A weakly anchoring liquid crystal aligning agent containing a polymer α, which is a component that exhibits weak anchoring properties, and a polymer β, which is a component that does not exhibit weak anchoring properties and exhibits a uniaxial alignment regulating force through alignment treatment. coating on a substrate and providing a thin film on the substrate;
a step of subjecting the thin film to an orientation treatment;
A method for manufacturing a substrate with a weak anchoring alignment film, comprising:
The method for manufacturing a substrate with a weak anchoring alignment film according to claim 1, wherein the polymer β is a polymer that has a horizontal alignment regulating force when subjected to an alignment treatment.
The method for manufacturing a substrate with a weak anchoring alignment film according to claim 1, wherein the weak anchoring alignment film is a liquid crystal alignment film that has been subjected to a uniaxial alignment treatment.
The method for producing a substrate with a weak anchoring alignment film according to claim 1, wherein the polymer α contains at least one selected from the group consisting of Polymer A, Polymer B, and Polymer C below.
Polymer A: A block copolymer having a block segment (A) that is compatible with the liquid crystal and a block segment (B) that is not compatible with the liquid crystal or becomes insolubilized in the liquid crystal upon firing.
Polymer B: a graft copolymer having a backbone polymer and a branch polymer bonded to the backbone polymer as a side chain of the backbone polymer, wherein the branch polymer is compatible with the liquid crystal and the backbone polymer is not compatible with the liquid crystal or becomes incompatible with the liquid crystal upon firing.
Polymer C: A polymer that has a polymer unit that is compatible with the liquid crystal and reacts with the polymer β when heated.
The block segment (A) in the polymer A is a compound represented by the following formula (2), a compound represented by the following formula (3), a compound represented by the following formula (4), and the following formula ( 5) contains as a constituent component at least one selected from the group consisting of the compounds represented by
The block segment (B) in the polymer A contains a compound represented by the following formula (6) as a constituent component,
A method for manufacturing a substrate with a weak anchoring alignment film according to claim 4.

(In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond. , R 1 represents an alkyl group having 1 to 20 carbon atoms which may have a bonding group inserted therein, and n is an integer of 1 to 2. When n is 2, the two X and R 1 are each the same. (It may be different or it may be different.)

(In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms which may have a bonding group inserted therein. , T represents an organic group represented by the following formula (3-T), and n is an integer of 1 to 2. When n is 2, the two Ts may be the same or different. (However, when n is 2, S represents a saturated hydrocarbon group having 1 to 6 carbon atoms that may have a bonding group inserted.)

(In formula (3-T), * indicates a bonding site. X is a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si(R 1 )(R 2 )- (R 1 and R 2 each independently represent an alkyl group bonded to Si.), -Si(R 3 )(R 4 )-O-(R 3 and R 4 each independently bond to Si. represents an alkyl group), and -N(R 5 )-(R 5 represents a hydrogen atom or an alkyl group bonded to N), and Cy is a 6- to 20-membered non-ring group. (Represents an aromatic cyclic group.)

(In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R 1 represents an aliphatic hydrocarbon group having a linear or branched structure having 1 to 10 carbon atoms, and 3 Each of the three X's independently represents a hydrogen atom or the following formula (4-X).However, at least one of the three X's represents the formula (4-X).)

(In formula (4-X), Y represents a single bond, -O-, -S-, or -N(R)-(R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms bonded to N. ), and * indicates a bonding site. R 2 , R 3 , and R 4 each independently represent an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group that may have a substituent. )

(In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and R 1 to R 3 are each independently a single bond or the number of carbon atoms into which a bonding group may be inserted. represents an alkylene group of 1 to 6, Ar represents an aromatic hydrocarbon group that may have a substituent, and X 1 and X 2 are each independently a hydrogen atom, or R 1 X 1 and R 2 X 2 and the carbon atoms bonded to R 1 X 1 and R 2 X 2 may form a ring together. The total number of carbon atoms in R 1 X 1 , R 2 X 2 and R 3 is 1 or more.)

(In formula (6), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and n is an integer of 1 to 2. Z represents a group represented by the following formula (6-Z). (If n is 2, the two Zs may be the same or different.)

(In formula (6-Z), L is a trialkoxysilyl group, an isocyanate group, a blocked isocyanate group, an epoxy group, an oxetane group, a vinyl group, an allyl group, an oxazoline group, an amino group, a protected amino group, an aniline group, a protected aniline group) group, hydroxy group, protected hydroxy group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxy group, maleimide group, N-hydroxysuccinimide ester group, bonding group Aromatic hydrocarbon group having 5 to 18 carbon atoms which may have a bonding group inserted therein, an aromatic heterocyclic group having 5 to 18 carbon atoms which may have a bonding group inserted therein, a cinnamic acid group, a cinnamic acid aromatic ester group , a cinnamic acid alkyl ester group, a cinnamyl group, a phenylbenzoate group, an azobenzene group, an N-benzylideneaniline group, a stilbene group, and a tolan group. J is a single bond or has 1 to 1 carbon atoms. 6 represents an aliphatic hydrocarbon group.When K is bonded to an aromatic hydrocarbon group, it represents a linking group selected from a single bond, an ether bond, an ester bond, an amide bond, a urea bond, a urethane bond, and a thioether bond. In other cases, it indicates a single bond. * represents a binding site. m is an integer from 1 to 3. When m is 2 or 3, multiple K and L may be the same. (However, if J is a single bond, m is 1.)
5. The method for producing a substrate with a weak anchoring alignment film according to claim 4, wherein the branch polymer in the polymer B is derived from a macromonomer represented by the following formula (7).

(In formula (7), P represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and Q represents a polymerizable monomer containing at least one of the compounds represented by the following formulas (2) to (5). (n is an integer of 1 to 2. When n is 2, the two Qs may be the same or different.)

(In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond. , R 1 represents an alkyl group having 1 to 20 carbon atoms which may have a bonding group inserted therein, and n is an integer of 1 to 2. When n is 2, the two X and R 1 are each the same. (It may be different or it may be different.)

(In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms which may have a bonding group inserted therein. , T represents an organic group represented by the following formula (3-T), and n is an integer of 1 to 2. When n is 2, the two Ts may be the same or different. (However, when n is 2, S represents a saturated hydrocarbon group having 1 to 6 carbon atoms that may have a bonding group inserted.)

(In formula (3-T), * indicates a bonding site. X is a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si(R 1 )(R 2 )- (R 1 and R 2 each independently represent an alkyl group bonded to Si.), -Si(R 3 )(R 4 )-O-(R 3 and R 4 each independently bond to Si. represents an alkyl group), and -N(R 5 )-(R 5 represents a hydrogen atom or an alkyl group bonded to N), and Cy is a 6- to 20-membered non-ring group. (Represents an aromatic cyclic group.)

(In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R 1 represents an aliphatic hydrocarbon group having a linear or branched structure having 1 to 10 carbon atoms, and 3 Each of the three X's independently represents a hydrogen atom or the following formula (4-X).However, at least one of the three X's represents the formula (4-X).)

(In formula (4-X), Y represents a single bond, -O-, -S-, or -N(R)-(R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms bonded to N. ), and * indicates a bonding site. R 2 , R 3 , and R 4 each independently represent an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group that may have a substituent. )

(In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and R 1 to R 3 are each independently a single bond or the number of carbon atoms into which a bonding group may be inserted. represents an alkylene group of 1 to 6, Ar represents an aromatic hydrocarbon group that may have a substituent, and X 1 and X 2 are each independently a hydrogen atom, or R 1 X 1 and R 2 X 2 and the carbon atoms bonded to R 1 X 1 and R 2 X 2 may form a ring together. The total number of carbon atoms in R 1 X 1 , R 2 X 2 and R 3 is 1 or more.)
5. The method for manufacturing a substrate with a weak anchoring alignment film according to claim 4, wherein the backbone polymer in the polymer B contains a compound represented by the following formula (6) as a constituent component.

(In formula (6), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and n is an integer of 1 to 2. Z represents a group represented by the following formula (6-Z). (If n is 2, the two Zs may be the same or different.)

(In formula (6-Z), L is a trialkoxysilyl group, an isocyanate group, a blocked isocyanate group, an epoxy group, an oxetane group, a vinyl group, an allyl group, an oxazoline group, an amino group, a protected amino group, an aniline group, a protected aniline group) group, hydroxy group, protected hydroxy group, phenol group, protected phenol group, thiol group, protected thiol group, thiophenol group, protected thiophenol group, aldehyde group, carboxy group, maleimide group, N-hydroxysuccinimide ester group, bonding group Aromatic hydrocarbon group having 5 to 18 carbon atoms which may have a bonding group inserted therein, an aromatic heterocyclic group having 5 to 18 carbon atoms which may have a bonding group inserted therein, a cinnamic acid group, a cinnamic acid aromatic ester group , a cinnamic acid alkyl ester group, a cinnamyl group, a phenylbenzoate group, an azobenzene group, an N-benzylideneaniline group, a stilbene group, and a tolan group. J is a single bond or has 1 to 1 carbon atoms. 6 represents an aliphatic hydrocarbon group.When K is bonded to an aromatic hydrocarbon group, it represents a linking group selected from a single bond, an ether bond, an ester bond, an amide bond, a urea bond, a urethane bond, and a thioether bond. In other cases, it indicates a single bond. * represents a binding site. m is an integer from 1 to 3. When m is 2 or 3, multiple K and L may be the same. (However, if J is a single bond, m is 1.)
The method for manufacturing a substrate with a weak anchoring alignment film according to claim 4, wherein the polymer C is a polymer represented by the following formula (8).

(In formula (8), A is an n-valent organic compound having a molecular weight of 500 or less and having a group that reacts with the polymer β upon heating, selected from the following formulas (8-A-1) to (8-A-16). represents a group.
Q is a divalent polymer unit that is compatible with the liquid crystal and contains as a constituent at least one kind selected from the group consisting of compounds represented by the following formulas (2) to (5).
R is a monovalent organic group selected from the following formulas (8-R-1) to (8-R-11) and having a molecular weight of 500 or less that does not react with the polymer β upon heating.
n is an integer from 1 to 2. When n is 2, the two Q's and R's may be the same or different. )

(In formulas (8-A-1) to (8-A-16), R 1 and R 2 each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and R 3 and R 4 each independently represents a single bond or a linear or branched alkylene group having 1 to 12 carbon atoms, and X represents an oxygen atom or a sulfur atom. * represents a bonding site.)

(In formulas (8-R-1) to (8-R-11), R 1 and R 2 each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and R 3 and Each R 4 independently represents a single bond or a linear or branched alkylene group having 1 to 12 carbon atoms. * represents a bonding site.)

(In formula (2), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and X represents a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, or thioether bond. , R 1 represents an alkyl group having 1 to 20 carbon atoms which may have a bonding group inserted therein, and n is an integer of 1 to 2. When n is 2, the two X and R 1 are each the same. (It may be different or it may be different.)

(In formula (3), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and S represents a single bond or a saturated hydrocarbon group having 1 to 6 carbon atoms which may have a bonding group inserted therein. , T represents an organic group represented by the following formula (3-T), and n is an integer of 1 to 2. When n is 2, the two Ts may be the same or different. (However, when n is 2, S represents a saturated hydrocarbon group having 1 to 6 carbon atoms that may have a bonding group inserted.)

(In formula (3-T), * indicates a bonding site. X is a single bond, ether bond, ester bond, amide bond, urethane bond, urea bond, thioether bond, -Si(R 1 )(R 2 )- (R 1 and R 2 each independently represent an alkyl group bonded to Si.), -Si(R 3 )(R 4 )-O-(R 3 and R 4 each independently bond to Si. represents an alkyl group), and -N(R 5 )-(R 5 represents a hydrogen atom or an alkyl group bonded to N), and Cy is a 6- to 20-membered non-ring group. (Represents an aromatic cyclic group.)

(In formula (4), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, R 1 represents an aliphatic hydrocarbon group having a linear or branched structure having 1 to 10 carbon atoms, and 3 Each of the three X's independently represents a hydrogen atom or the following formula (4-X).However, at least one of the three X's represents the formula (4-X).)

(In formula (4-X), Y represents a single bond, -O-, -S-, or -N(R)-(R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms bonded to N. ), and * indicates a bonding site. R 2 , R 3 , and R 4 each independently represent an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group that may have a substituent. )

(In formula (5), M represents a polymerizable group having a polymerizable unsaturated hydrocarbon group, and R 1 to R 3 are each independently a single bond or the number of carbon atoms into which a bonding group may be inserted. represents an alkylene group of 1 to 6, Ar represents an aromatic hydrocarbon group that may have a substituent, and X 1 and X 2 are each independently a hydrogen atom, or R 1 X 1 and R 2 X 2 and the carbon atoms bonded to R 1 X 1 and R 2 X 2 may form a ring together. The total number of carbon atoms in R 1 X 1 , R 2 X 2 and R 3 is 1 or more.)
M in the formula (2) is any of the structures represented below,
M in the formula (3) is any of the structures represented below,
M in the formula (4) is any of the structures represented below,
M in the formula (5) is any of the structures represented below,
A method for manufacturing a substrate with a weak anchoring alignment film according to any one of claims 5, 6, and 8.

(In the formula, R 1 and R 2 each independently represent a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and X, Y, and Z each independently represent an oxygen atom or a sulfur atom. *, * 1 and * 2 represent bonding sites, and either one of * 1 and * 2 may be replaced with a hydrogen atom or a straight chain or branched alkyl group having 1 to 12 carbon atoms. n is Represents an integer from 1 to 5.)
The weak anchoring alignment film according to claim 1, wherein the polymer β is at least one kind of polymer selected from the group consisting of polyimide, polyamic acid, polyamic acid ester, polyamide, polyurea, and poly(meth)acrylate. Substrate manufacturing method.
A polyimide precursor, in which the polymer β is obtained by polymerizing a diamine component and a tetracarboxylic acid derivative component containing at least one compound selected from the group consisting of tetracarboxylic dianhydride and its derivative; 2. The method for producing a substrate with a weak anchoring alignment film according to claim 1, wherein the polymer is a polymer selected from the group consisting of polyimides that are imidized products of the polyimide precursor.
The method for manufacturing a substrate with a weak anchoring alignment film according to claim 11, wherein the tetracarboxylic acid derivative component includes a tetracarboxylic dianhydride represented by the following formula (9).

(In formula (9), X represents a structure selected from the group consisting of the following formulas (X-1) to (X-17) and (XR-1) to (XR-2).)

(In formulas (X-1) to (X-17), R 1 to R 4 are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, Alkynyl group having 2 to 6 carbon atoms, monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, alkoxy group having 1 to 6 carbon atoms, alkoxyalkyl group having 2 to 6 carbon atoms, 2 to 6 carbon atoms represents an alkyloxycarbonyl group or a phenyl group. R 5 and R 6 each independently represent a hydrogen atom or a methyl group.
In formulas (XR-1) to (XR-2), j and k are integers of 0 or 1, and A 1 and A 2 each independently represent a single bond, -O-, -CO-, -COO-, represents a phenylene group, a sulfonyl group, or an amide group. The plurality of A2 's may be the same or different.
*1 is a bond bonded to one acid anhydride group, and *2 is a bond bonded to the other acid anhydride group. )
The method for manufacturing a substrate with a weak anchoring alignment film according to claim 12, wherein the formula (X-1) is selected from the group consisting of the following formulas (X1-1) to (X1-6).

(In formulas (X1-1) to (X1-6), *1 is a bond that is bonded to one acid anhydride group, and *2 is a bond that is bonded to the other acid anhydride group.)
The method for manufacturing a substrate with a weak anchoring alignment film according to claim 11, wherein the diamine component includes a diamine represented by the following formula (10).

(In formula (10), Ar 1 and Ar 1' each independently represent a benzene ring, a biphenyl structure, or a naphthalene ring, and one or more of the benzene ring, the biphenyl structure, or the naphthalene ring The hydrogen atom of may be substituted with a monovalent group. L 1 and L 1' each independently represent a single bond, -O-, -C(=O)-, or -O-C(= O)-.A represents -CH 2 -, an alkylene group having 2 to 12 carbon atoms, or between the carbon-carbon bond of the alkylene group, -O-, -C(=O)-O-, Represents a divalent organic group in which at least one of the following groups is inserted:
The method for manufacturing a substrate with a weakly anchoring alignment film according to claim 4, wherein the polymer C is a polymer obtained by living polymerization or chain transfer polymerization.
A method for manufacturing a liquid crystal display element, comprising the step of manufacturing a substrate with a weak anchoring alignment film by the method for manufacturing a substrate with a weak anchoring alignment film according to claim 1.