CN114174907A

CN114174907A - Transverse electric field liquid crystal display element and method for manufacturing transverse electric field liquid crystal cell

Info

Publication number: CN114174907A
Application number: CN202080053711.9A
Authority: CN
Inventors: 野田尚宏; 筒井皇晶
Original assignee: Nissan Chemical Corp
Current assignee: Nissan Chemical Corp
Priority date: 2019-07-29
Filing date: 2020-07-28
Publication date: 2022-03-11
Also published as: KR20220039756A; JPWO2021020399A1; TW202118812A; WO2021020399A1

Abstract

A lateral electric field liquid crystal display element having: the liquid crystal display element is obtained by filling a liquid crystal composition between the liquid crystal alignment film and the liquid crystal alignment film, and the anchoring energy of the liquid crystal alignment film on the counter substrate side is smaller than that of the liquid crystal alignment film on the comb electrode substrate side.

Description

Transverse electric field liquid crystal display element and method for manufacturing transverse electric field liquid crystal cell

Technical Field

The present invention relates to a lateral electric field liquid crystal display device having both high-speed response and high backlight transmittance and having a high voltage holding ratio, and a method for manufacturing a lateral electric field liquid crystal cell that can be used for manufacturing the lateral electric field liquid crystal display device.

Background

In recent years, liquid crystal display elements have been widely used in displays for mobile phones, computers, and televisions. Liquid crystal display elements have characteristics such as being thin, lightweight, and low in power consumption, and are expected to be applied to further contents such as vr (visual reality) and ultra-high definition displays in the future. Various display modes such as tn (twisted nematic), IPS (In-Plane Switching), va (vertical alignment), and the like have been proposed as display modes of liquid crystal displays, but a film (liquid crystal alignment film) for inducing liquid crystals into a desired alignment state is used In all modes.

In particular, in products having a touch panel such as a tablet PC, a smartphone, and a smart TV, an IPS mode in which display is not disturbed easily even when touched is preferable, and in recent years, liquid crystal display elements using ffs (fringe Field switching) and technologies using a non-contact technology using photo-alignment have been used in order to improve contrast and viewing angle characteristics.

In recent years, an IPS mode using weak anchoring has been proposed, and it has been reported that by using this method, a large transmittance improvement and low-voltage driving can be achieved as compared with the conventional IPS mode (see patent document 1). Specifically, a method of manufacturing an IPS mode liquid crystal display element using a liquid crystal alignment film having strong anchoring ability on one substrate and a treatment not having alignment regulating force of liquid crystal on the substrate side having one electrode for generating a lateral electric field.

In recent years, a technique of making a weakly anchored state using a thick polymer brush or the like and weakly anchoring the IPS mode has been proposed (patent documents 2 and 3). By this technique, a contrast ratio is greatly improved or a driving voltage is greatly reduced.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 4053530

Patent document 2: japanese patent laid-open publication No. 2013-231757

Patent document 3: international patent application publication No. 2019-004433 pamphlet

Disclosure of Invention

Problems to be solved by the invention

In the technique using weak anchoring, since the transmittance can be improved by the IPS mode, it is considered that expensive substrate cost such as Vcom shift, which is a problem of the FFS mode, can be eliminated, but on the other hand, the IPS mode has a problem in miniaturization of the comb-teeth type electrode, and there are also problems such as difficulty in pattern quality management and poor yield. Therefore, it is considered that a technique applicable to FFS is required.

On the other hand, this technique has a problem that in the FFS driving method, if the anchoring energy on the electrode substrate side is reduced, the transmittance of light from the backlight tends to be deteriorated due to a state of the liquid crystal at the interface of the weak anchor film. It is known that FFS is different from IPS in the way of applying an electric field being non-uniform, and this is considered to be because, particularly in the case where the anchoring energy is generated in the polar angle direction even if the FFS is minute in a weakly anchored state, if the FFS is set in the weakly anchored state, the liquid crystal does not receive the orientation restriction force and moves with a weak force, and therefore the liquid crystal in the region near the vertical electric field on the electrode substrate side which normally does not move moves, causing disclination (disclination), and conversely, causing a decrease in transmittance.

In weak anchoring by adding a polymerizable compound to a liquid crystal, it is considered that a decrease in voltage holding ratio, burn-in, and the like are caused by the additive.

If the above technical problem can be solved, it is considered that: panel manufacturers have been advantageous in terms of battery consumption reduction, image quality improvement, and the like.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a lateral electric field liquid crystal display element having both high-speed response and high backlight transmittance, and having a high voltage holding ratio and being difficult to cause burn-in ("burn-in" japanese-language "manufactured by a sintered き - き"), and a lateral electric field liquid crystal cell that can be used to manufacture the same.

Means for solving the problems

The present inventors have conducted intensive studies to solve the above problems, and as a result, have found that the above problems can be solved, and have completed the present invention having the following gist.

Namely, the present invention includes the following.

[1] A lateral electric field liquid crystal display element having: the liquid crystal display device is characterized by comprising a comb-shaped electrode substrate provided with a liquid crystal alignment film and a counter substrate provided with a liquid crystal alignment film, wherein the 2 liquid crystal alignment films are made to face each other, the liquid crystal display element is obtained by filling liquid crystal between the liquid crystal alignment film and the liquid crystal alignment film, and the anchoring energy of the liquid crystal alignment film on the counter substrate side is smaller than that of the liquid crystal alignment film on the comb-shaped electrode substrate side.

[2] The transverse electric field liquid crystal display element according to [1], wherein the liquid crystal alignment film on the comb-teeth electrode substrate side and the liquid crystal alignment film on the counter substrate side are both liquid crystal alignment films obtained by uniaxial alignment treatment, and only the liquid crystal alignment film on the counter substrate side is weakly anchored.

[3] The transverse electric field liquid crystal display element according to [1] or [2], wherein the comb-teeth electrode substrate is an IPS substrate or an FFS substrate.

[4] The transverse electric field liquid crystal display element according to any one of [1] to [3], wherein the liquid crystal alignment film on the counter substrate side is: the liquid crystal composition is obtained by polymerizing the radical polymerizable compound in a state where the liquid crystal composition containing the liquid crystal and the radical polymerizable compound is brought into contact with the radical generating film.

[5] The transverse electric field liquid crystal display element according to [4], wherein the radical generating film is a film in which an organic group that induces radical polymerization is immobilized.

[6] The transverse electric field liquid crystal display element according to [4] or [5], wherein the radical generating film comprises a polymer containing an organic group which induces radical polymerization.

[7] The transverse electric field liquid crystal display element according to [6], wherein the polymer having an organic group which induces radical polymerization is at least one polymer selected from a polyimide precursor obtained by using a diamine component, a polyimide, a polyurea and a polyamide, and the diamine component contains a diamine having an organic group which induces radical polymerization.

[8] The transverse electric field liquid crystal display element according to [6] or [7], wherein the organic group that induces radical polymerization is an organic group represented by the following structures [ X-1] to [ X-18], [ W ], [ Y ], or [ Z ].

[ chemical formula 1]

(formula [ X-1]]～[X-18]In which denotes a bonding site, S₁And S₂Each independently represents-O-, -NR-, or-S-, wherein R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (in the alkyl group having 1 to 10 carbon atoms, the alkyl group having 2 to 10 carbon atoms is-CH₂Part of the radicals may be substituted by oxygen atoms; wherein S is₂In R or NR, in the above-mentioned alkyl group, -CH₂When a part of the group is replaced by an oxygen atom, the oxygen atom is bonded to S₂Or N is not directly bonded); r¹And R²Each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 4 carbon atoms)

[ chemical formula 2]

(formula [ W)]、[Y]And [ Z]Wherein Ar represents a bonding site, and Ar represents a group selected from the group consisting ofAromatic hydrocarbon groups in phenylene, naphthylene and biphenylene radicals, R⁹And R¹⁰Each independently represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, in R⁹And R¹⁰In the case of an alkyl group, the groups may be bonded to each other at the ends to form a ring structure; q represents any one of the following structures;

[ chemical formula 3]

(in the formula, R¹¹represents-CH₂-, -NR-, -O-or-S-, R independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and represents a bonding site); s³Represents a single bond, -O-, -NR- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) or-S-; r¹²Represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms).

[9] The transverse electric field liquid crystal display element according to [7], wherein the diamine having an organic group which induces radical polymerization is a diamine having a structure represented by the following general formula (6) or the following general formula (7),

[ chemical formula 4]

(in the formula (6), R⁶Represents a single bond, -CH₂-、-O-、-COO-、-OCO-、-NHCO-、-CONH-、-NH-、-CH₂O-、-N(CH₃)-、-CON(CH₃) -or-N (CH)₃)CO-，

R⁷Represents a single bond, or an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with a fluorine atom, or any of-CH's of the alkylene groups₂-or-CF ₂1 or more of-may be independently substituted with a group selected from-CH- ═ CH-, a divalent carbocyclic ring and a divalent heterocyclic ring, and further, any of the groups mentioned below, i.e., -O-, -COO-, -OCO-, -NHCO-, -CONH-or-NH-may not be mutually exclusiveUnder ortho conditions, may be substituted by these groups;

R⁸is represented by the formula [ X-1] selected from]～[X-18]A radical polymerization reactive group represented by the formula (1);

[ chemical formula 5]

(formula [ X-1]]～[X-18]In which denotes a bonding site, S₁And S₂Each independently represents-O-, -NR-, or-S-, wherein R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (in the alkyl group having 1 to 10 carbon atoms, the alkyl group having 2 to 10 carbon atoms is-CH₂Part of the radicals may be substituted by oxygen atoms; wherein S is₂In R or NR, in the above-mentioned alkyl group, -CH₂When a part of the group is replaced by an oxygen atom, the oxygen atom is bonded to S₂Or N is not directly bonded); r¹And R²Each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 4 carbon atoms. )

[ chemical formula 6]

(in the formula (7), T¹And T²Each independently is a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH₂O-、-N(CH₃)-、-CON(CH₃) -or-N (CH)₃)CO-，

S represents a single bond, or an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with a fluorine atom, or any of-CH' S of the alkylene groups₂-or-CF₂Each of 1 or more of-may be independently substituted with a group selected from-CH ═ CH-, a divalent carbocyclic ring and a divalent heterocyclic ring, and further. May be substituted by any of the groups mentioned below, i.e., -O-, -COO-, -OCO-, -NHCO-, -CONH-or-NH-under the condition that these groups are not adjacent to one another,

j is an organic group represented by a chemical formula selected from the group consisting of [ W ], [ Y ] and [ Z ] below;

[ chemical formula 7]

(formula [ W)]、[Y]And [ Z]In the formula, represents and T²Ar represents an aromatic hydrocarbon group selected from the group consisting of phenylene, naphthylene and biphenylene which may have an organic group and/or a halogen atom as a substituent, and R⁹And R¹⁰Each independently represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms,

q represents any one of the following structures;

[ chemical formula 8]

(in the formula, R¹¹represents-CH₂-, -NR-, -O-or-S-, R independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and represents a bonding site),

R¹²represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms;

S³represents a single bond, -O-, -NR- (R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) or-S-).

[10] The transverse electric field liquid crystal display element according to any one of [4] to [9], wherein at least one of the radical polymerizable compounds is a compound having compatibility with a liquid crystal and having one polymerizable reactive group in one molecule.

[11] The transverse electric field liquid crystal display device according to [10], wherein the polymerizable reactive group of the radical polymerizable compound is selected from the following structures.

[ chemical formula 9]

(wherein, represents a bonding site; R^bA linear alkyl group having 2 to 8 carbon atoms, E represents a bonding group selected from the group consisting of a single bond, -O-, -NRc-, -S-, an ester bond and an amide bond; rc represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. )

[12] The transverse electric field liquid crystal display element according to any one of [4] to [11], wherein the radical polymerizable compound is a radical polymerizable compound in which Tg of a polymer obtained by polymerizing the radical polymerizable compound is 100 ℃ or lower.

[13] A method of fabricating a lateral electric field liquid crystal cell, comprising:

preparing a comb-teeth electrode substrate as a first substrate having a liquid crystal alignment film and a counter substrate as a second substrate having a radical generating film,

a step of forming a cell so that the radical generating film on the second substrate faces the first substrate, and

and a step of filling a liquid crystal composition containing a liquid crystal and a radical polymerizable compound between the first substrate and the second substrate.

[14] The method of manufacturing a transverse electric field liquid crystal cell according to [13], wherein the second substrate is a substrate coated with a liquid crystal alignment film having uniaxial alignment properties.

[15] The method for manufacturing a transverse electric field liquid crystal cell according to [14], wherein the liquid crystal alignment film having a uniaxial alignment property is a liquid crystal alignment film for horizontal alignment.

[16] The method of manufacturing a lateral electric field liquid crystal cell according to any one of [13] to [15], wherein the comb-teeth electrode substrate is an IPS substrate or an FFS substrate.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the transverse electric field liquid crystal display element, screen burning is not easy to occur, and high backlight transmissivity, high response speed and high voltage holding ratio can be achieved.

Drawings

Fig. 1 is a schematic cross-sectional view showing an example of a lateral electric field liquid crystal display element of the present invention.

Fig. 2 is a schematic cross-sectional view showing another example of the in-plane switching mode liquid crystal display device of the present invention.

Detailed Description

The liquid crystal display element for a transverse electric field according to the present invention includes: a liquid crystal display element for transverse electric field is obtained by filling a liquid crystal composition between two liquid crystal alignment films, wherein the comb-teeth electrode substrate with a liquid crystal alignment film and the counter substrate with a liquid crystal alignment film are arranged such that 2 liquid crystal alignment films are opposed to each other, and the anchoring energy of the liquid crystal alignment film on the counter substrate side is smaller than that of the liquid crystal alignment film on the comb-teeth electrode substrate side.

More preferably, the liquid crystal alignment film on the counter substrate side is a weak anchoring film.

Note that, the anchoring energy in this specification means: anchoring energy in the in-plane direction of the liquid crystal alignment film, that is, azimuthal anchoring energy. The azimuthal anchoring energy can be determined, for example, by a method of estimating a driving threshold voltage in an electro-optical response of a liquid crystal cell (Frederix transfer method), a method of estimating a threshold voltage in a capacitance change (strong electric field method, capacitance method), a method of evaluating an optical response of a liquid crystal by applying a strong magnetic field to a liquid crystal cell, and the like (the contents are described in detail in the Japanese society for liquid Crystal, Nakagaku, 17 years, Vol.9.No.4 liquid Crystal chemical laboratory lecture: interfacial anchoring energy coefficient measuring method). However, the above methods have various prerequisites, and only a film having a strong anchoring energy can be used for the research, and a method for accurately determining a very weak anchoring energy is currently being studied.

Fig. 1 is a schematic cross-sectional view showing an example of a lateral electric field liquid crystal display device of the present invention, and is an example of an IPS mode liquid crystal display device.

In the lateral electric field liquid crystal display element 1 illustrated in fig. 1, a liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 provided with a liquid crystal alignment film 2c and a counter substrate 4 provided with a liquid crystal alignment film 4 a. The comb-shaped electrode substrate 2 includes: a substrate 2a, a plurality of linear electrodes 2b formed on the substrate 2a and arranged in a comb-tooth shape, and a liquid crystal alignment film 2c formed on the substrate 2a so as to cover the linear electrodes 2 b. The counter substrate 4 includes a base 4b and a liquid crystal alignment film 4a formed on the base 4 b. In the transverse electric field liquid crystal display element 1, the anchoring energy of the liquid crystal alignment film 4a on the counter substrate 4 side is smaller than the anchoring energy of the liquid crystal alignment film 2c on the comb-teeth electrode substrate 2 side. The liquid crystal alignment film 4a is, for example, a weak anchoring film obtained by chemically changing a radical generating film. The liquid crystal alignment film on the counter substrate side is obtained, for example, by polymerizing a radical polymerizable compound in a state where a liquid crystal composition containing a liquid crystal and the radical polymerizable compound is brought into contact with a radical generating film.

In the lateral electric field liquid crystal display element 1, if a voltage is applied to the linear electrodes 2b, an electric field is generated between the linear electrodes 2b as indicated by electric field lines L.

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

In the lateral electric field liquid crystal display element 1 illustrated in fig. 2, a liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 provided with a liquid crystal alignment film 2h and a counter substrate 4 provided with a liquid crystal alignment film 4 a. The comb-teeth electrode substrate 2 includes a base material 2d, a surface electrode 2e formed on the base material 2d, an insulating film 2f formed on the surface electrode 2e, a plurality of linear electrodes 2g formed on the insulating film 2f and arranged in a comb-tooth shape, and a liquid crystal alignment film 2h formed on the insulating film 2f so as to cover the linear electrodes 2 g. The counter substrate 4 includes a base 4b and a liquid crystal alignment film 4a formed on the base 4 b. In the transverse electric field liquid crystal display element 1, the anchoring energy of the liquid crystal alignment film 4a on the counter substrate 4 side is smaller than the anchoring energy of the liquid crystal alignment film 2h on the comb-teeth electrode substrate 2 side. The liquid crystal alignment film 4a is, for example, a weak anchoring film obtained by chemically changing a radical generating film. The liquid crystal alignment film on the counter substrate side is obtained by, for example, polymerizing a radical polymerizable compound in a state where a liquid crystal composition containing a liquid crystal and the radical polymerizable compound is brought into contact with a radical generating film.

In the lateral electric field liquid crystal display element 1, if a voltage is applied to the face electrode 2e and the linear electrode 2g, an electric field is generated between the face electrode 2e and the linear electrode 2g as indicated by electric field lines L.

"weakly anchored membrane" means: a film in which the alignment regulating force of liquid crystal molecules in the in-plane direction is not at all present or, even if present, is weaker than the intermolecular force between liquid crystals, and the liquid crystal molecules cannot be uniaxially aligned in any direction only by the film. Further, the weak anchoring film is not limited to a solid film, but includes a liquid film covering a solid surface. In general, in a liquid crystal display element, liquid crystal is aligned by using a pair of films for regulating the alignment of liquid crystal molecules, that is, liquid crystal alignment films. This is because the alignment regulating force of the liquid crystal alignment film is also transmitted in the thickness direction of the liquid crystal layer by the intermolecular force between the liquid crystal molecules, and as a result, the liquid crystal molecules near the weak anchor film are also aligned. Therefore, when a liquid crystal alignment film for horizontal alignment is used as the liquid crystal alignment film, the entire liquid crystal cell can be aligned horizontally. The horizontal orientation means: the liquid crystal molecules are aligned with their long axes almost parallel to the liquid crystal alignment film surface, and the horizontal alignment is also included in the range of the tilt alignment of about several degrees.

The weak anchor film can be obtained by polymerizing a polymerizable compound by UV or heat in a state where a liquid crystal containing a specific polymerizable compound is brought into contact with a radical generating film, for example. More specifically, a method for manufacturing a weakly anchoring film, comprising: the method includes the steps of preparing a unit having a liquid crystal composition containing a liquid crystal and a radical polymerizable compound between a first substrate having a liquid crystal alignment film and a second substrate having a radical generating film, and polymerizing the radical polymerizable compound in the unit. Preferably, the method for manufacturing a liquid crystal cell includes: preparing a first substrate having a liquid crystal alignment film and a second substrate having a radical generating film; a step in which the production unit causes the radical generating film to face the first substrate; and a step of filling a liquid crystal composition containing a liquid crystal and a radical polymerizable compound between the first substrate and the second substrate. For example, the present invention relates to a method for manufacturing a low-voltage driven transverse electric field liquid crystal display element, wherein the first substrate is a substrate having no radical generating film and a liquid crystal alignment film obtained by uniaxial alignment treatment, and the first substrate is a substrate having comb teeth electrodes.

On the other hand, the weakly anchored state refers to: the state of slightly having an alignment regulating force is a state of not having a regulating force for aligning the liquid crystal, but having an optical anisotropy, and the magnitude of the anchoring energy is 10^-3～10^-6(J/m²) The range of (1).

The weakly anchored state can be obtained, for example, by applying a manufacturing method of a weakly anchored film in a state where the second substrate having the radical generating film described above is subjected to an alignment treatment. The alignment treatment may be performed by a rubbing method or may be performed by photo-alignment.

[ composition for Forming free-radical-generating film ]

The radical generating film-forming composition for forming the radical generating film used in the present invention contains, for example, a polymer as a component, and contains a group capable of generating radicals. In this case, the composition may contain a polymer in which a group capable of generating a radical is bonded, or may be a composition of a compound having a group capable of generating a radical and a polymer forming a base resin. By applying the composition and curing the composition to form a film, a radical generating film in which a radical generating group is immobilized in the film can be obtained. The group capable of generating a radical is preferably an organic group which induces radical polymerization.

Examples of the organic group that induces radical polymerization include organic groups represented by chemical formulas selected from the group consisting of the formulas [ X-1] to [ X-18], [ W ], [ Y ] and [ Z ].

Here, Ar in the formulae [ W ], [ Y ] and [ Z ] represents an aromatic hydrocarbon group selected from the group consisting of phenylene, naphthylene and biphenylene. Further, the aromatic hydrocarbon group may have an organic group and/or a halogen atom as a substituent.

Formula [ X-1]～[X-18]In R of (A), as alkyl, -CH₂Alkyl groups having 2 to 10 carbon atoms, part of which may be substituted with oxygen atoms, and examples thereof include alkoxy groups having 1 to 9 carbon atoms. Wherein S is₂R of R or NR is not an alkoxy group.

The polymer is preferably at least 1 polymer selected from polyimide precursors, polyimides, polyureas, polyamides, polyacrylates, polymethacrylates, and the like.

In order to obtain the radical generating film used in the present invention, when a polymer having an organic group which induces radical polymerization is used, in order to obtain a polymer having a group capable of generating radicals, it is preferable to use, as a monomer component, a monomer having a photoreactive side chain containing at least one selected from the group consisting of a methacryl group, an acryl group, a vinyl group, an allyl group, a coumarinyl group, a styryl group, and a cinnamoyl group, or a monomer which is decomposed by irradiation with ultraviolet rays and has a radical generating site in the side chain. On the other hand, since a monomer generating a radical itself is considered to form an unstable compound due to a problem such as spontaneous polymerization, a polymer derived from a diamine having a radical generation site is preferable in terms of ease of synthesis, and polyimide precursors such as polyamic acid and polyamic acid ester, polyimide, polyurea, and polyamide are more preferable.

The diamine containing a free radical generating site is specifically, for example, a diamine generating a radical and having a polymerizable side chain, and examples thereof include a diamine represented by the above formula (6), but are not limited thereto.

Two amino groups (-NH) in the formula (6)₂) The bonding position of (2) is not limited. Specifically, examples of the bonding group to the side chain include a 2,3 position, a 2,4 position, a 2,5 position, a 2,6 position, a 3,4 position, and a 3,5 position on the benzene ring. Among them, from the viewpoint of reactivity in synthesizing a polyamic acid, a position of 2,4, a position of 2,5, or a position of 3,5 is preferable. In view of easiness in synthesizing the diamine, the 2,4 position or the 3,5 position is more preferable.

Specific examples of the diamine having a photoreactive group containing at least 1 selected from the group consisting of a methacryl group, an acryl group, a vinyl group, an allyl group, a coumarinyl group, a styryl group, and a cinnamoyl group include the following compounds, but are not limited thereto.

[ chemical formula 10]

(in the formula, J¹Is a bonding group selected from the group consisting of a single bond, -O-, -COO-, -NHCO-and-NH-, J²Represents a single bond, or an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with a fluorine atom)

The diamine having a site which is decomposed by ultraviolet irradiation to generate a radical as a side chain includes the diamine represented by the above formula (7), but is not limited thereto.

Two amino groups (-NH) in the above formula (7)₂) The bonding position of (2) is not limited. Specifically, examples of the bonding group to the side chain include a 2,3 position, a 2,4 position, a 2,5 position, a 2,6 position, a 3,4 position, and a 3,5 position on the benzene ring. Among them, from the viewpoint of reactivity in synthesizing a polyamic acid, a position of 2,4, a position of 2,5, or a position of 3,5 is preferable.

In particular, the structure represented by the following chemical formula is most preferable in view of ease of synthesis, high versatility, characteristics, and the like, but is not limited thereto.

[ chemical formula 11]

(wherein n is an integer of 2 to 8.)

The diamine may be used in a mixture of 1 or 2 or more depending on the characteristics such as liquid crystal alignment property, polymerization reaction sensitivity, voltage holding property, and accumulated charge when the diamine is formed into a radical generating film.

The diamine having a site where radical polymerization occurs is preferably used in an amount of 5 to 50 mol%, more preferably 10 to 40 mol%, and particularly preferably 15 to 30 mol% based on the total amount of the diamine component for polymer synthesis contained in the radical generating film-forming composition.

When the polymer used for the radical generating film of the present invention is obtained from a diamine, a diamine other than the diamine having a radical generating site may be used as the diamine component as long as the effect of the present invention is not impaired. Specific examples thereof include p-phenylenediamine, 2,3,5, 6-tetramethyl-p-phenylenediamine, 2, 5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2, 4-dimethyl-m-phenylenediamine, 2, 5-diaminotoluene, 2, 6-diaminotoluene, 2, 5-diaminophenol, 2, 4-diaminophenol, 3, 5-diaminobenzyl alcohol, 2, 4-diaminobenzyl alcohol, 4, 6-diaminoresorcinol, 4 '-diaminobiphenyl, 3' -dimethyl-4, 4 '-diaminobiphenyl, 3' -dimethoxy-4, 4 '-diaminobiphenyl, 3' -dihydroxy-4, 4 '-diaminobiphenyl, 2, 5-dimethyl-p-phenylenediamine, 2, 4-diaminotoluene, 2, 5-diaminophenol, 3, 5-diaminobenzyl alcohol, 2, 4-diaminobenzyl alcohol, 4, 6-diaminoresorcinol, 4' -diaminobiphenyl, 3 '-dimethyl-4, 4' -diaminobiphenyl, 3 '-dihydroxy-4, 4' -diaminobiphenyl, 2, 5-d-m-phenylene diamine, 3,3 '-dicarboxy-4, 4' -diaminobiphenyl, 3 '-difluoro-4, 4' -diaminobiphenyl, 3 '-bis (trifluoromethyl) -4,4' -diaminobiphenyl, 3 '-diaminobiphenyl, 2' -diaminobiphenyl, 2,3 '-diaminobiphenyl, 4' -diaminodiphenylmethane, 3 '-diaminodiphenylmethane, 3,4' -diaminodiphenylmethane, 2 '-diaminodiphenylmethane, 2,3' -diaminodiphenylmethane, 4 '-diaminodiphenyl ether, 3' -diaminodiphenyl ether, 3,4 '-diaminodiphenyl ether, 2-bis (trifluoromethyl) biphenyl, 3' -diaminodiphenyl ether, and mixtures thereof, 2,2 '-diaminodiphenyl ether, 2,3' -diaminodiphenyl ether, 4 '-sulfonyldiphenylamine, 3' -sulfonyldiphenylamine, bis (4-aminophenyl) silane, bis (3-aminophenyl) silane, dimethyl-bis (4-aminophenyl) silane, dimethyl-bis (3-aminophenyl) silane, 4 '-thiodiphenylamine, 3' -thiodiphenylamine, 4 '-diaminodiphenylamine, 3' -diaminodiphenylamine, 3,4 '-diaminodiphenylamine, 2' -diaminodiphenylamine, 2,3 '-diaminodiphenylamine, N-methyl (4,4' -diaminodiphenyl) amine, N-methyl (3,3' -diaminodiphenyl) amine, N-methyl (3,4' -diaminodiphenyl) amine, N-methyl (2,2' -diaminodiphenyl) amine, N-methyl (2,3' -diaminodiphenyl) amine, 4' -diaminobenzophenone, 3' -diaminobenzophenone, 3,4' -diaminobenzophenone, 2' -diaminobenzophenone, 2,3' -diaminobenzophenone, 1, 4-diaminonaphthalene, 1, 5-diaminonaphthalene, 1, 6-diaminonaphthalene, 1, 7-diaminonaphthalene, 1, 8-diaminonaphthalene, 2, 5-diaminonaphthalene, 2, 6-diaminonaphthalene, 2, 7-diaminonaphthalene, 1, 2-bis (4-aminophenyl) ethane, 1, 2-bis (3-aminophenyl) ethane, 1, 3-bis (4-aminophenyl) propane, 1, 3-bis (3-aminophenyl) propane, 1, 4-bis (4-aminophenyl) butane, 1, 4-bis (3-aminophenyl) butane, bis (3, 5-diethyl-4-aminophenyl) methane, 1, 4-bis (4-aminophenoxy) benzene, 1, 3-bis (4-aminophenoxy) benzene, 1, 4-bis (4-aminophenyl) benzene, 1, 3-bis (4-aminophenyl) benzene, 1, 4-bis (4-aminobenzyl) benzene, 1, 3-bis (4-aminophenoxy) benzene, 4' - [1, 4-phenylenebis (methylene) ] diphenylamine, 4,4' - [1, 3-phenylenebis (methylene) ] diphenylamine, 3,4' - [1, 4-phenylenebis (methylene) ] diphenylamine, 3,4' - [1, 3-phenylenebis (methylene) ] diphenylamine, 3' - [1, 4-phenylenebis (methylene) ] diphenylamine, 3' - [1, 3-phenylenebis (methylene) ] diphenylamine, 1, 4-phenylenebis [ (4-aminophenyl) methanone ], 1, 4-phenylenebis [ (3-aminophenyl) methanone ], 1, 3-phenylenebis [ (4-aminophenyl) methanone ], 1, 3-phenylenebis [ (3-aminophenyl) methanone ], 1, 4-phenylenebis (4-aminobenzoate), 1, 4-phenylenebis (3-aminobenzoate), 1, 3-phenylenebis (4-aminobenzoate), 1, 3-phenylenebis (3-aminobenzoate), bis (4-aminophenyl) terephthalate, bis (3-aminophenyl) terephthalate, bis (4-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, N '- (1, 4-phenylene) bis (4-aminobenzamide), N' - (1, 3-phenylene) bis (4-aminobenzamide), N '- (1, 4-phenylene) bis (3-aminobenzamide), N' - (1, 3-phenylene) bis (3-aminobenzamide), N, N ' -bis (4-aminophenyl) terephthalamide, N ' -bis (3-aminophenyl) terephthalamide, N ' -bis (4-aminophenyl) isophthalamide, N ' -bis (3-aminophenyl) isophthalamide, 9, 10-bis (4-aminophenyl) anthracene, 4' -bis (4-aminophenoxy) diphenylsulfone, 2' -bis [4- (4-aminophenoxy) phenyl ] propane, 2' -bis [4- (4-aminophenoxy) phenyl ] hexafluoropropane, 2' -bis (4-aminophenyl) hexafluoropropane, 2' -bis (3-amino-4-methylphenyl) hexafluoropropane, 2,2 '-bis (4-aminophenyl) propane, 2' -bis (3-amino-4-methylphenyl) propane, trans-1, 4-bis (4-aminophenyl) cyclohexane, 3, 5-diaminobenzoic acid, 2, 5-diaminobenzoic acid, bis (4-aminophenoxy) methane, 1, 2-bis (4-aminophenoxy) ethane, 1, 3-bis (4-aminophenoxy) propane, 1, 3-bis (3-aminophenoxy) propane, 1, 4-bis (4-aminophenoxy) butane, 1, 4-bis (3-aminophenoxy) butane, 1, 5-bis (4-aminophenoxy) pentane, 2 '-bis (3-aminophenyl) propane, 2' -bis (3-aminophenyl) propane, trans-1, 4-aminophenyl) cyclohexane, 3, 5-diaminobenzoic acid, 2, 5-diaminobenzoic acid, bis (4-aminophenoxy) methane, 1, 2-bis (4-aminophenoxy) ethane, 1, 3-bis (4-aminophenoxy) pentane, 1, 3-bis (4-aminophenoxy) pentane, 1, 5-pentane, 1, 4-pentane, 3-bis (4-aminophenoxy) pentane, 1, 3-pentane, 3-bis (4-amino-4-pentane, 1, 3-4-n-pentane, 3-n-2, 3-hexane, 1, 3-hexane, 1, 3-hexane, 2, 3-hexane, or toluene, 3-hexane, or one, or one, or more, 1, 5-bis (3-aminophenoxy) pentane, 1, 6-bis (4-aminophenoxy) hexane, 1, 6-bis (3-aminophenoxy) hexane, 1, 7-bis (4-aminophenoxy) heptane, 1, 7-bis (3-aminophenoxy) heptane, 1, 8-bis (4-aminophenoxy) octane, 1, 8-bis (3-aminophenoxy) octane, 1, 9-bis (4-aminophenoxy) nonane, 1, 9-bis (3-aminophenoxy) nonane, 1, 10-bis (4-aminophenoxy) decane, 1, 10-bis (3-aminophenoxy) decane, 1, 11-bis (4-aminophenoxy) undecane, 1, 11-bis (3-aminophenoxy) undecane, Aromatic diamines such as 1, 12-bis (4-aminophenoxy) dodecane and 1, 12-bis (3-aminophenoxy) dodecane; alicyclic diamines such as bis (4-aminocyclohexyl) methane and bis (4-amino-3-methylcyclohexyl) methane; aliphatic diamines such as 1, 3-diaminopropane, 1, 4-diaminobutane, 1, 5-diaminopentane, 1, 6-diaminohexane, 1, 7-diaminoheptane, 1, 8-diaminooctane, 1, 9-diaminononane, 1, 10-diaminodecane, 1, 11-diaminoundecane, and 1, 12-diaminododecane; diamines having a urea structure such as 1, 3-bis [2- (p-aminophenyl) ethyl ] urea and 1, 3-bis [2- (p-aminophenyl) ethyl ] -1-tert-butoxycarbonylurea; diamines having a nitrogen-containing unsaturated heterocyclic structure, such as N-p-aminophenyl-4-p-aminophenyl (tert-butoxycarbonyl) aminomethylpiperidine; and diamines having an N-Boc group (Boc represents a t-butoxycarbonyl group), such as N-t-butoxycarbonyl-N- (2- (4-aminophenyl) ethyl) -N- (4-aminobenzyl) amine.

The other diamines may be used in combination of 1 or 2 or more depending on the properties such as liquid crystal alignment property, polymerization reaction sensitivity, voltage holding property, and accumulated charge when the film is formed as a radical generating film.

In the synthesis of the polymer being a polyamic acid, the tetracarboxylic dianhydride to be reacted with the diamine component is not particularly limited. Specific examples thereof include pyromellitic acid, 2,3,6, 7-naphthalene tetracarboxylic acid, 1,2,5, 6-naphthalene tetracarboxylic acid, 1,4,5, 8-naphthalene tetracarboxylic acid, 2,3,6, 7-anthracene tetracarboxylic acid, 1,2,5, 6-anthracene tetracarboxylic acid, 3,3',4,4' -biphenyl tetracarboxylic acid, 2,3,3',4' -biphenyl tetracarboxylic acid, bis (3, 4-dicarboxyphenyl) ether, 3,3',4,4' -benzophenonetetracarboxylic acid, bis (3, 4-dicarboxyphenyl) sulfone, bis (3, 4-dicarboxyphenyl) methane, 2-bis (3, 4-dicarboxyphenyl) propane, 1,1,1,3,3, 3-hexafluoro-2, 2-bis (3, 4-dicarboxyphenyl) propane, bis (3, 4-dicarboxyphenyl) dimethylsilane, bis (3, 4-dicarboxyphenyl) diphenylsilane, 2,3,4, 5-pyridinetetracarboxylic acid, 2, 6-bis (3, 4-dicarboxyphenyl) pyridine, 3',4,4' -diphenylsulfonetetracarboxylic acid, 3,4,9, 10-perylenetetracarboxylic acid, 1, 3-diphenyl-1, 2,3, 4-cyclobutanetetracarboxylic acid, oxydiphthalic acid, 1,2,3, 4-cyclobutanetetracarboxylic acid, 1,2,3, 4-cyclopentanetetracarboxylic acid, 1,2,4, 5-cyclohexanetetracarboxylic acid, 1,2,3, 4-tetramethyl-1, 2,3, 4-cyclobutanetetracarboxylic acid, 1, 2-dimethyl-1, 2,3, 4-cyclobutanetetracarboxylic acid, 1, 3-dimethyl-1, 2,3, 4-cyclobutanetetracarboxylic acid, 1,2,3, 4-cycloheptanetetracarboxylic acid, 2,3,4, 5-tetrahydrofuranetetracarboxylic acid, 3, 4-dicarboxy-1-cyclohexylsuccinic acid, 2,3, 5-tricarboxycyclopentylacetic acid, 3, 4-dicarboxy-1, 2,3, 4-tetrahydro-1-naphthalenecarboxylic acid, bicyclo [3,3,0] octane-2, 4,6, 8-tetracarboxylic acid, bicyclo [4,3,0] nonane-2, 4,7, 9-tetracarboxylic acid, bicyclo [4,4,0] decane-2, 4,8, 10-tetracarboxylic acid, tricyclo [6.3.0.0<2,6> ] undecane-3, 5,9, 11-tetracarboxylic acid, 1,2,3, 4-butanetetracarboxylic acid, 4- (2, 5-dioxotetrahydrofuran-3-yl) -1,2,3, 4-tetrahydronaphthalene-1, 2-dicarboxylic acid, bicyclo [2,2,2] oct-7-ene-2, 3,5, 6-tetracarboxylic acid, 5- (2, 5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexane-1, 2-dicarboxylic acid, tetracyclo [6,2,1,1,0<2,7> ] dodecane-4, 5,9, 10-tetracarboxylic acid, 3,5, 6-tricarboxynorbornane-2: 3,5: 6-dicarboxylic acid, 1,2,4, a dianhydride of a tetracarboxylic acid such as 5-cyclohexanetetracarboxylic acid.

Of course, the tetracarboxylic dianhydride may be used in combination of 1 type or 2 or more depending on the characteristics such as liquid crystal alignment property, sensitivity of polymerization reaction, voltage holding property, and accumulated charge when a radical generating film is formed.

In the synthesis when the polymer is a polyamic acid ester, the structure of the tetracarboxylic acid dialkyl ester to be reacted with the diamine component is not particularly limited, and specific examples thereof are given below.

Specific examples of the aliphatic tetracarboxylic acid diester include dialkyl 1,2,3, 4-cyclobutanetetracarboxylic acid, dialkyl 1, 2-dimethyl-1, 2,3, 4-cyclobutanetetracarboxylic acid, dialkyl 1, 3-dimethyl-1, 2,3, 4-cyclobutanetetracarboxylic acid, dialkyl 1,2,3, 4-tetramethyl-1, 2,3, 4-cyclobutanetetracarboxylic acid, dialkyl 1,2,3, 4-cyclopentanetetracarboxylic acid, dialkyl 2,3,4, 5-tetrahydrofurante, dialkyl 1,2,4, 5-cyclohexanetetracarboxylic acid, dialkyl 3, 4-dicarboxy-1-cyclohexylsuccinate, dialkyl 3, 4-dicarboxy-1, 2,3, 4-tetrahydro-1-naphthalenetetracarboxylic acid, Dialkyl 1,2,3, 4-butanetetracarboxylic acid ester, dialkyl bicyclo [3,3,0] octane-2, 4,6, 8-tetracarboxylic acid ester, dialkyl 3,3',4,4' -dicyclohexyltetracarboxylic acid ester, dialkyl 2,3, 5-tricarboxycyclopentylacetate, cis-3, 7-dibutylcyclooctan-1, 5-diene-1, 2,5, 6-tetracarboxylic acid ester, dialkyl tricyclo [4.2.1.0<2,5> ] nonane-3, 4,7, 8-tetracarboxylic acid-3, 4:7, 8-dialkyl ester, hexacyclic [6.6.0.1<2,7> ] 0<3,6>.1<9,14>.0<10,13> ] hexanecane-4, 5,11, 12-tetracarboxylic acid-4, 5:11, 12-dialkyl ester, 2,7, 6, 1<9 >, 14> ], 0<10,13> ] Dialkyl 4- (2, 5-dioxotetrahydrofuran-3-yl) -1,2,3, 4-tetrahydronaphthalene-1, 2-dicarboxylate, and the like.

Examples of the aromatic tetracarboxylic acid dialkyl ester include a dialkyl pyromellitate, a

dialkyl

3,3',4,4' -biphenyltetracarboxylic acid ester, a

dialkyl

2,2',3,3' -biphenyltetracarboxylic acid ester, a

dialkyl

2,3,3', 4-biphenyltetracarboxylic acid ester, a

dialkyl

3,3',4,4' -benzophenonetetracarboxylate, a

dialkyl

2,3,3',4' -benzophenonetetracarboxylate, a dialkyl bis (3, 4-dicarboxyphenyl) ether ester, a dialkyl bis (3, 4-dicarboxyphenyl) sulfone ester, a

dialkyl

1,2,5, 6-naphthalenetetracarboxylate, and a

dialkyl

2,3,6, 7-naphthalenetetracarboxylate.

In the synthesis of the polymer in the case of polyurea, the diisocyanate to be reacted with the diamine component is not particularly limited, and may be used in accordance with availability and the like. The specific structure of the diisocyanate is shown below.

[ chemical formula 12]

In the formula R₂₂And R₂₃Represents an aliphatic hydrocarbon group having 1 to 10 carbon atoms.

The aliphatic diisocyanates represented by K-1 to K-5 have poor reactivity but have the advantage of improving solvent solubility, and the aromatic diisocyanates represented by K-6 to K-13 have the effect of improving heat resistance while being rich in reactivity, but have the disadvantage of reducing solvent solubility. In general use and characteristics, K-1, K-7, K-8, K-9 and K-10 are preferable, K-12 is preferable from the viewpoint of electrical characteristics, and K-13 is preferable from the viewpoint of liquid crystal alignment properties. The diisocyanate may be used in combination of 2 or more, and is preferably used in various applications depending on the desired properties.

In addition, a part of diisocyanate may be replaced with the tetracarboxylic dianhydride described above, and may be used in the form of a copolymer of polyamic acid and polyurea, or may be used in the form of a copolymer of polyimide and polyurea by chemical imidization.

In the synthesis of a polyamide as a polymer, the structure of the dicarboxylic acid to be reacted is not particularly limited, and specific examples thereof are as follows. Examples of the aliphatic dicarboxylic acid include dicarboxylic acids such as malonic acid, oxalic acid, dimethylmalonic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, hexadiene diacid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2-dimethylglutaric acid, 3-diethylsuccinic acid, azelaic acid, sebacic acid, and suberic acid.

Examples of the alicyclic dicarboxylic acid include 1, 1-cyclopropanedicarboxylic acid, 1, 2-cyclopropanedicarboxylic acid, 1-cyclobutanedicarboxylic acid, 1, 2-cyclobutanedicarboxylic acid, 1, 3-cyclobutanedicarboxylic acid, 3, 4-diphenyl-1, 2-cyclobutanedicarboxylic acid, 2, 4-diphenyl-1, 3-cyclobutanedicarboxylic acid, 1-cyclobutane-1, 2-dicarboxylic acid, 1-cyclobutane-3, 4-dicarboxylic acid, 1-cyclopentanedicarboxylic acid, 1, 2-cyclopentanedicarboxylic acid, 1, 3-cyclopentanedicarboxylic acid, 1-cyclohexanedicarboxylic acid, 1, 2-cyclohexanedicarboxylic acid, 1, 3-cyclohexanedicarboxylic acid, 1, 4-cyclohexanedicarboxylic acid, 1, 2-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] octane dicarboxylic acid, 1, 3-adamantanedicarboxylic acid, 4, 8-dioxo-1, 3-adamantanedicarboxylic acid, 2, 6-spiro [3.3] heptane dicarboxylic acid, 1, 3-adamantane diacetic acid, camphoric acid, and the like.

Examples of the aromatic dicarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, 5-methylisophthalic acid, 5-t-butylisophthalic acid, 5-aminoisophthalic acid, 5-hydroxyisophthalic acid, 2, 5-dimethylterephthalic acid, tetramethylterephthalic acid, 1, 4-naphthalenedicarboxylic acid, 2, 5-naphthalenedicarboxylic acid, 2, 6-naphthalenedicarboxylic acid, 2, 7-naphthalenedicarboxylic acid, 1, 4-anthracenedicarboxylic acid, 1, 4-anthraquinonedicarboxylic acid, 2, 5-biphenyldicarboxylic acid, 4' -biphenyldicarboxylic acid, 1, 5-biphenyldicarboxylic acid, 4' -terphthalic acid, 4' -diphenylmethane dicarboxylic acid, 4' -diphenylethane dicarboxylic acid, 4' -diphenylpropane dicarboxylic acid, 5-butylisophthalic acid, 5-aminoisophthalic acid, 5-hydroxyisophthalic acid, 2, 5-dimethylterephthalic acid, 1, 4-naphthalenedicarboxylic acid, 4' -biphenyldicarboxylic acid, 4' -diphenylpropane dicarboxylic acid, 5-dimethylnaphthalene dicarboxylic acid, 5-naphthalenedicarboxylic acid, 4' -naphthalenedicarboxylic acid, 4' -diphenylethane dicarboxylic acid, 4-naphthalenedicarboxylic acid, 4-dicarboxylic acid, and the like, 4,4' -diphenylhexafluoropropanedicarboxylic acid, 4' -diphenyletherdicarboxylic acid, 4' -bibenzyldicarboxylic acid, 4' -stilbenedicarboxylic acid, 4' -diphenylacetylenedicarboxylic acid (4,4' -tolanedicarboxylic acid), 4' -carbonyldibenzoic acid, 4' -sulfonyldibenzoic acid, 4' -dithiodibenzoic acid, p-phenylenediacetic acid, 3' -p-phenylenedipropionic acid, 4-carboxycinnamic acid, p-phenylenediacrylic acid, 3' - [4,4' - (methylenedi-p-phenylene) ] dipropionic acid, 4' - [4,4' - (oxydiphenylene) ] dibutanoic acid, 4' - (oxydiphenylene) ] dibutanoic acid, Dicarboxylic acids such as (isopropylidenedip-phenylenedioxy) dibutyrate and bis (p-carboxyphenyl) dimethylsilane.

Examples of the dicarboxylic acid containing a heterocycle 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, 5-pyridinedicarboxylic acid, 2, 6-pyridinedicarboxylic acid, 3, 4-pyridinedicarboxylic acid, and 3, 5-pyridinedicarboxylic acid.

The various dicarboxylic acids described above may be in the structure of acid dihalides or anhydrides. The dicarboxylic acid is particularly preferably a dicarboxylic acid capable of giving a polyamide having a linear structure, from the viewpoint of maintaining the orientation of the liquid crystal molecules. Among them, terephthalic acid, isophthalic acid, 1, 4-cyclohexanedicarboxylic acid, 4' -biphenyldicarboxylic acid, 4' -diphenylmethanedicarboxylic acid, 4' -diphenylethanedicarboxylic acid, 4' -diphenylpropanedicarboxylic acid, 4' -diphenylhexafluoropropanedicarboxylic acid, 2-bis (phenyl) propanedicarboxylic acid, 4-terphenyldicarboxylic acid, 2, 6-naphthalenedicarboxylic acid, 2, 5-pyridinedicarboxylic acid, acid dihalides thereof, and the like are preferably used. The above-mentioned compounds may be present as isomers, and may be mixtures containing them. In addition, 2 or more compounds may be used in combination. The dicarboxylic acids used in the present invention are not limited to the above-mentioned exemplary compounds.

In the case of obtaining a polyamic acid, polyamic acid ester, polyurea, and polyamide by the reaction of a diamine (also referred to as "diamine component") as a raw material and a component selected from a tetracarboxylic dianhydride (also referred to as "tetracarboxylic dianhydride component"), a tetracarboxylic diester, a diisocyanate, and a dicarboxylic acid as a raw material, a known synthesis means can be used. In general, the method is a method of reacting a diamine component and one or more components selected from a tetracarboxylic dianhydride component, a tetracarboxylic diester, a diisocyanate, and a dicarboxylic acid in an organic solvent.

The reaction of the diamine component with the tetracarboxylic dianhydride component is advantageous in the following respects: the method is easy to carry out in an organic solvent, and does not produce byproducts.

The organic solvent used in the above reaction is not particularly limited as long as it dissolves the polymer formed. Further, even if the organic solvent is an organic solvent that does not dissolve the polymer, the organic solvent may be used in combination with the above-mentioned solvent within a range that the polymer to be produced does not precipitate. Since moisture in the organic solvent acts as a cause of inhibiting the polymerization reaction and hydrolyzing the polymer formed, it is preferable to use an organic solvent that has been dehydrated and dried.

Examples of the organic solvent include N, N-dimethylformamide, N-dimethylacetamide, N-diethylformamide, N-methylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1, 3-dimethyl-2-imidazolidinone, 3-methoxy-N, N-dimethylpropanamide, N-methylcaprolactam, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexamethylsulfoxide, gamma-butyrolactone, isopropanol, methoxymethylpentanol, dipentene, ethylpentyl ketone, methylnonyl ketone, methylethylketone, methylisoamylketone, methylisopropylketone, methylcellosolve, ethylcellosolve, methylcellosolve acetate, dimethylvalerolactone, dimethylcellosolve, ethylcellosolve acetate, and dimethylcellosolve acetate, Butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol 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, ethyl carbitol, ethylene glycol monoacetate, ethylene glycol monoacetyl ether, diethylene glycol monomethyl ether, propylene glycol monoethyl ether, and mixtures thereof, Diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane, n-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, ethylene carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentanone, 2-ethyl-1-hexanol, and the like. The organic solvents mentioned above may be used alone or in combination.

When the diamine component and the tetracarboxylic dianhydride component are reacted in an organic solvent, the following method may be mentioned: a method of adding the tetracarboxylic dianhydride component directly or by dispersing or dissolving the diamine component in the organic solvent by stirring a solution obtained by dispersing or dissolving the diamine component in the organic solvent; a method of adding a diamine component to a solution obtained by dispersing or dissolving a tetracarboxylic dianhydride component in an organic solvent; a method of alternately adding a tetracarboxylic dianhydride component and a diamine component. Any of the above methods may be used. In the case where the diamine component or the tetracarboxylic dianhydride component is composed of a plurality of compounds, these components may be reacted in a state of being mixed in advance, or they may be reacted in sequence, or low molecular weight materials obtained by the respective reactions may be further subjected to a mixing reaction to produce a high molecular weight material.

The temperature at which the diamine component and the tetracarboxylic dianhydride component are reacted may be selected from any temperature, for example, from-20 to 100 ℃, preferably from-5 to 80 ℃. The reaction can be carried out at any concentration, and for example, the total amount of the diamine component and the tetracarboxylic dianhydride component is 1 to 50% by mass, preferably 5 to 30% by mass, based on the reaction solution.

The ratio of the total mole number of the tetracarboxylic dianhydride component to the total mole number of the diamine component in the polymerization reaction can be arbitrarily selected depending on the molecular weight of the polyamic acid to be obtained. As in the case of the usual polycondensation reaction, the closer the molar ratio is to 1.0, the larger the molecular weight of the polyamic acid produced. The preferable range is 0.8 to 1.2.

The method for synthesizing the polymer used in the present invention is not limited to the above method, and when synthesizing polyamic acid, the corresponding polyamic acid is obtained by reacting a tetracarboxylic acid derivative having a corresponding structure, such as tetracarboxylic acid or a tetracarboxylic acid dihalide, with a known method, in place of the tetracarboxylic acid dianhydride, as in the case of the general method for synthesizing polyamic acid. In the case of synthesizing polyurea, a diamine may be reacted with a diisocyanate. In the production of the polyamic acid ester or the polyamide, the diamine and a component selected from the group consisting of a tetracarboxylic acid diester and a dicarboxylic acid may be derivatized to an acid halide in the presence of a known condensing agent or by a known method, and then reacted with the diamine.

Examples of the method for imidizing a polyamic acid to obtain a polyimide include thermal imidization in which a solution of a polyamic acid is directly heated, and catalytic imidization in which a catalyst is added to a solution of a polyamic acid. The imidization ratio of the polyamic acid to the polyimide is preferably 30% or more from the viewpoint of improving the voltage holding ratio, and is preferably 80% or less from the viewpoint of whitening characteristics, that is, from the viewpoint of suppressing the deposition of a polymer in the varnish.

The temperature at which the polyamic acid is thermally imidized in a solution is usually 100 to 400 ℃, preferably 120 to 250 ℃, and is preferably carried out while removing water generated by the imidization reaction from the system.

The catalytic imidization of the polyamic acid can be carried out by adding a basic catalyst and an acid anhydride to a solution of the polyamic acid, and stirring the mixture at a temperature of usually-20 to 250 ℃ and preferably 0 to 180 ℃. The amount of the basic catalyst is usually 0.5 to 30 times, preferably 2 to 20 times, the amount of the acid anhydride is usually 1 to 50 times, preferably 3 to 30 times, the amount of the acid amide group. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine, and among these, pyridine is preferable because it has a suitable basic property for allowing the reaction to proceed. The acid anhydride includes acetic anhydride, trimellitic anhydride, pyromellitic anhydride, and the like, and among these, acetic anhydride is preferable because purification after completion of the reaction is easy. The imidization rate based on the catalytic imidization can be controlled by adjusting the amount of the catalyst and the reaction temperature, the reaction time, and the like.

When the polymer to be produced is recovered from the reaction solution of the polymer, the reaction solution may be precipitated by charging the poor solvent. Examples of the poor solvent used for the formation of the precipitate include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and water. The polymer precipitated by being put into the poor solvent may be recovered by filtration, and then dried at normal temperature or under reduced pressure or by heating. Further, if the operation of re-dissolving the polymer obtained by the precipitation recovery in the organic solvent and re-precipitating and recovering is repeated 2 to 10 times, impurities in the polymer can be reduced. Examples of the poor solvent in this case include alcohols, ketones, hydrocarbons and the like, and if 3 or more kinds of poor solvents selected from them are used, purification efficiency is further improved, and therefore, it is preferable.

In addition, in the case where the above-mentioned radical generating film comprises a polymer containing an organic group which induces radical polymerization, the radical generating film forming composition used in the present invention may comprise other polymers than the polymer containing an organic group which induces radical polymerization. In this case, the content of the other polymer in the total polymer component is preferably 5 to 95% by mass, more preferably 30 to 70% by mass.

In consideration of the strength of the radical generating film obtained by coating the radical generating film, workability in forming the coating film, uniformity of the coating film, and the like, the molecular weight of the polymer contained in the radical generating film forming composition is preferably 5000 to 1000000, more preferably 10000 to 150000, in terms of a weight average molecular weight measured by a Gel Permeation Chromatography (GPC) method.

As the polymer used in the radical generating film of the present invention obtained by applying a composition of a compound having a radical generating group and a polymer and curing the composition to form a film to fix the composition in the film, at least 1 polymer selected from a polyimide precursor, a polyimide, a polyurea, a polyamide, a polyacrylate, a polymethacrylate, and the like produced by the above production method may be used, the polymer being obtained using a diamine component which is 0 mol% of the diamine component having a site where radical polymerization occurs in the total diamine component used for synthesis of the polymer contained in the radical generating film forming composition. The compound having a radical-generating group to be added at this time includes the following compounds.

The compound that generates radicals by heat is a compound that generates radicals by heating to a decomposition temperature or higher. Examples of the radical thermal polymerization initiator include ketone peroxides (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), diacyl peroxides (acetyl peroxide, benzoyl peroxide, etc.), hydroperoxides (hydrogen peroxide, t-butyl hydroperoxide, cumene hydroperoxide, etc.), dialkyl peroxides (di-t-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc.), peroxy acetals (dibutyl peroxycyclohexane, etc.), peroxy alkyl esters (tert-butyl peroxyneodecanoate, tert-butyl peroxypivalate, tert-amyl peroxy-2-ethylcyclohexane, etc.), persulfates (potassium persulfate, sodium persulfate, ammonium persulfate, etc.), azo compounds (azobisisobutyronitrile, 2' -bis (2-hydroxyethyl) azobisisobutyronitrile, etc.). The radical thermal polymerization initiator may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

The compound that generates radicals by light is not particularly limited as long as it is a compound that initiates radical polymerization by light irradiation. Examples of the radical photopolymerization initiator include benzophenone, Michler's ketone, 4' -bis (diethylamino) benzophenone, xanthone, thioxanthone, isopropyl xanthone, 2, 4-diethylthioxanthone, 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methyl-4 ' -isopropylacetone, 1-hydroxycyclohexylphenyl ketone, isopropylbenzoin ether, isobutylbenzoin ether, 2-diethoxyacetophenone, 2-dimethoxy-2-phenylacetophenone, camphorquinone, benzanthrone, 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholinopropan-1-one, and mixtures thereof, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, 4-dimethylaminobenzoic acid ethyl ester, 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-bis (ethoxycarbonylmethyl) ] -2, 6-bis (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, and mixtures thereof, 2-mercaptobenzothiazole, 3' -carbonylbis (7-diethylaminocoumarin), 2- (o-chlorophenyl) -4,4',5,5' -tetraphenyl-1, 2' -biimidazole, 2' -bis (2-chlorophenyl) -4,4',5,5' -tetrakis (4-ethoxycarbonylphenyl) -1,2' -biimidazole, 2' -bis (2, 4-dichlorophenyl) -4,4',5,5' -tetraphenyl-1, 2' -biimidazole, 2' -bis (2, 4-dibromophenyl) -4,4',5,5' -tetraphenyl-1, 2' -biimidazole, 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-hydroxycyclohexylphenylketone, bis (5-2, 4-cyclopentadien-1-yl) -bis (2, 6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium, 3',4,4' -tetrakis (tert-butylperoxycarbonyl) benzophenone, 3',4,4' -tetrakis (tert-hexylperoxy carbonyl) benzophenone, 3' -bis (methoxycarbonyl) -4,4' -bis (tert-butylperoxycarbonyl) benzophenone, 3,4 '-bis (methoxycarbonyl) -4,3' -bis (tert-butylperoxycarbonyl) benzophenone, 4 '-bis (methoxycarbonyl) -3,3' -bis (tert-butylperoxycarbonyl) benzophenone, 2- (3-methyl-3H-benzothiazol-2-ylidene) -1-naphthalen-2-yl-ethanone or 2- (3-methyl-1, 3-benzothiazol-2 (3H) -ylidene) -1- (2-benzoyl) ethanone, and the like. The above compounds may be used alone, or 2 or more kinds thereof may be used in combination.

Even when the radical generating film contains a polymer containing an organic group which induces radical polymerization, the compound having a radical generating group may be contained in order to accelerate radical polymerization when energy is applied.

The radical generating film-forming composition may contain an organic solvent which dissolves or disperses the polymer component and other components than the radical generator used as necessary. The organic solvent is not particularly limited, and examples thereof include the organic solvents exemplified in the synthesis of the polyamic acid. Among them, from the viewpoint of solubility, N-methyl-2-pyrrolidone, γ -butyrolactone, N-ethyl-2-pyrrolidone, 1, 3-dimethyl-2-imidazolidinone, 3-methoxy-N, N-dimethylpropane amide, and the like are preferable. N-methyl-2-pyrrolidone or N-ethyl-2-pyrrolidone is particularly preferable, and a mixed solvent of 2 or more kinds may be used.

Further, it is preferable to use a solvent for improving the uniformity and smoothness of the coating film in combination with an organic solvent having high solubility of the components contained in the radical generating film forming composition.

Examples of the solvent for improving the uniformity and smoothness of the coating film include isopropyl alcohol, methoxymethylpentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol acetate, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol t-butyl ether, dipropylene glycol monomethyl ether, 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, ethylene glycol monomethyl ether, ethylene glycol methyl ether acetate, ethylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoacetate, ethylene glycol monomethyl ether, ethylene glycol monopropyl ether, ethylene glycol ether, propylene glycol monomethyl ether, propylene glycol ether, and mixtures thereof, 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, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methylethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl acetate, isopropyl propionate, isobutyl propionate, butyl acetate, butyl butyrate, butyl propionate, isobutyl propionate, ethyl propionate, butyl propionate, ethyl propionate, butyl propionate, ethyl propionate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2- (2-ethoxypropoxy) propanol, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate, 2-ethyl-1-hexanol, and the like. The above solvents may be mixed in plural. When the solvent is used, the amount of the solvent is preferably 5 to 80% by mass, more preferably 20 to 60% by mass, based on the total amount of the solvent contained in the liquid crystal aligning agent.

The radical generating film-forming composition may contain components other than those described above. Examples thereof include compounds which improve the film thickness uniformity and surface smoothness when the composition for forming a radical generating film is applied; a compound for improving the adhesion between the composition for forming a radical generating film and the substrate; a compound which further improves the film strength of the radical generating film forming composition, and the like.

Examples of the compound for improving the uniformity of the film thickness and the surface smoothness include a fluorine-based surfactant, a silicone-based surfactant, and a nonionic surfactant. More specifically, the examples include Eftop EF301, EF303, EF352 (manufactured by Mitsubishi Material electronics), MEGAFAC F171, F173, R-30 (manufactured by DIC), FLUORAD FC430, FC431 (manufactured by 3M), Asahiguard AG710, SURLON S-382, SC101, SC102, SC103, SC104, SC105, and SC106 (manufactured by AGC). When the surfactant is used, the amount thereof is preferably 0.01 to 2 parts by mass, and more preferably 0.01 to 1 part by mass, based on 100 parts by mass of the total amount of the polymers contained in the radical generating film-forming composition.

Specific examples of the compound for improving the adhesion between the radical generating film forming composition and the substrate include a functional silane-containing compound, an epoxy-containing compound, and the like. Examples thereof include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1, 4, 7-triazacyclodecane, 10-triethoxysilyl-1, 4, 7-triazacyclodecane, 9-trimethoxysilyl-3, 6-diazisononyl acetate, 9-triethoxysilyl-3, 6-diazisononyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxirane) -3-aminopropyltrimethoxysilane, N-bis (oxirane) -3-aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, dimethyl-ethyl-3-aminopropyltriethoxysilane, dimethyl-ethyl-3-aminopropyl-trimethoxysilane, dimethyl-3-amino-propyl-trimethoxysilane, dimethyl-3-ethyl-3-propyl-triethoxysilane, ethylene glycol diglycidyl ether, dimethyl-3-ethyl-propyl-trimethoxysilane, dimethyl-ethyl-3-ethyl-propyl-triethoxysilane, dimethyl-3-ethyl-3-propyl-trimethoxysilane, dimethyl-ethyl-3-ethyl-methyl-ethyl-3-propyl-trimethoxysilane, ethyl-, Polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1, 6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2-dibromoneopentyl glycol diglycidyl ether, 1,3,5, 6-tetraglycidyl-2, 4-hexanediol, N, N, N ', N ' -tetraglycidyl-m-phenylenediamine, 1, 3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ', N ' -tetraglycidyl-4, 4' -diaminodiphenylmethane, 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane, 3- (N, n-diglycidyl) aminopropyltrimethoxysilane, and the like.

In addition, in order to further improve the film strength of the radical generating film, a phenol compound such as 2,2' -bis (4-hydroxy-3, 5-dihydroxymethylphenyl) propane or tetrakis (methoxymethyl) bisphenol may be added. When the above compound is used, the amount is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, based on 100 parts by mass of the total amount of the polymers contained in the radical generating film-forming composition.

In addition, in the radical generating film forming composition, in addition to the above, a dielectric or conductive substance for changing electrical characteristics such as dielectric constant, conductivity and the like of the radical generating film may be added within a range not to impair the effects of the present invention.

[ radical generating film and liquid Crystal alignment film ]

The radical generating film of the present embodiment is obtained, for example, by using the radical generating film forming composition. For example, a cured film obtained by applying the composition for forming a radical generating film used in the present invention to a substrate and then drying and sintering the composition can be used as a radical generating film as it is. The cured film may be rubbed, irradiated with polarized light or light of a specific wavelength, and subjected to alignment treatment by ion beam treatment, so that the liquid crystal display element filled with liquid crystal may be irradiated with UV as an alignment film for PSA.

Examples of the method of applying the radical generating film forming composition include spin coating, printing, ink jet, spray, and roll coating, and the transfer printing method is widely used industrially from the viewpoint of productivity, and is also preferably used in the present invention.

The step of drying after application of the radical generating film-forming composition is not necessarily essential, but when the time from application to firing is not uniform among the substrates or when firing is not performed immediately after application, the step of drying is preferably included. The drying is not particularly limited as long as the solvent is removed to such an extent that the shape of the coating film is not deformed by transportation of the substrate or the like. For example, the following methods can be mentioned: drying the mixture on a hot plate at the temperature of 40-150 ℃, preferably 60-100 ℃ for 0.5-30 minutes, preferably 1-5 minutes.

The coating film formed by applying the radical generating film forming composition by the above method can be sintered to form a cured film. In this case, the sintering temperature may be generally any temperature of 100 to 350 ℃, preferably 140 to 300 ℃, more preferably 150 to 230 ℃, and still more preferably 160 to 220 ℃. The sintering time may be generally any time from 5 minutes to 240 minutes. Preferably 10 to 90 minutes, and more preferably 20 to 90 minutes. The heating may be performed by a known method, for example, a hot plate, a hot air circulation type oven, an IR (infrared) type oven, a belt oven, or the like.

The thickness of the cured film may be selected as needed, and is preferably 5nm or more, more preferably 10nm or more, because the reliability of the liquid crystal display device is easily obtained. In addition, when the thickness of the cured film is preferably 300nm or less, more preferably 150nm or less, the power consumption of the liquid crystal display element does not become extremely large, and therefore, the thickness is preferable.

The substrate having the radical generating film can be obtained as described above, but the radical generating film may be subjected to the uniaxial orientation treatment. Examples of the method of performing the uniaxial orientation treatment include a photo-orientation method, an oblique vapor deposition method, rubbing, a uniaxial orientation treatment by a magnetic field, and the like.

In the case of performing the alignment treatment by performing the rubbing treatment in one direction, for example, a rubbing roll around which a rubbing cloth is wound is rotated, and the substrate is moved so that the rubbing cloth comes into contact with the film. In the case of using the photo-alignment method, the entire surface of the film may be irradiated with polarized UV of a specific wavelength and heated as necessary to perform alignment treatment.

The liquid crystal alignment film of the present embodiment is obtained by the same method as that for the radical generating film except that a liquid crystal aligning agent is used instead of the radical generating film forming composition.

The substrate to which the radical generating film-forming composition is applied is not particularly limited as long as it is a substrate having high transparency.

Specific examples thereof include glass plates, polycarbonate, poly (meth) acrylate, polyethersulfone, polyarylate, polyurethane, polysulfone, polyether, polyetherketone, trimethylpentene, polyolefin, polyethylene terephthalate, (meth) acrylonitrile, triacetyl cellulose, diacetyl cellulose, and plastic plates such as cellulose acetate butyrate.

As a substrate to which the liquid crystal alignment film is applied, a transparent electrode for driving liquid crystal is preferably formed on the substrate. On a substrate that can be used in an IPS liquid crystal display device, an electrode pattern such as a standard IPS comb electrode, a PSA fishbone electrode, or a projection pattern such as MVA can be used.

In addition, in a high-functional element such as a TFT-type element, a substrate in which an element such as a transistor is formed between an electrode for driving liquid crystal and the substrate is used.

In the case of intentionally realizing a transmissive liquid crystal display element, the above-described substrate is generally used, but in the case of intentionally realizing a reflective liquid crystal display element, an opaque substrate such as a silicon wafer can be used as only one substrate. In this case, a material such as aluminum that reflects light may be used for the electrodes formed on the substrate.

In the case of rubbing the liquid crystal alignment film on the substrate on which the comb-teeth electrodes are formed, the rubbing direction is selected according to the electrical properties of the liquid crystal, but in the case of using a liquid crystal having positive dielectric anisotropy, the rubbing direction is preferably set to be substantially the same as the extending direction of the comb-teeth electrodes.

< liquid Crystal cell >

The liquid crystal cell of the present invention is obtained by, for example, disposing a substrate (second substrate) having a radical generating film formed on a substrate by the above-described method and a substrate (first substrate) having an electrode of a liquid crystal alignment film, facing the radical generating film and the liquid crystal alignment film with a spacer interposed therebetween, fixing the film with a sealant, injecting a liquid crystal composition containing a liquid crystal and a radical polymerizable compound, and sealing the film. In this case, the size of the separator used is usually 1 to 30 μm, preferably 2 to 10 μm. Further, the rubbing direction of the first substrate and the rubbing direction of the second substrate are parallel to each other, and thus the liquid crystal display device can be used in an IPS mode or an FFS mode, and can be used in a twisted nematic mode if the rubbing directions are arranged to be orthogonal to each other.

The comb electrode substrate used In the IPS (In-Plane Switching) mode, that is, the IPS substrate, includes a base material, a plurality of linear electrodes formed on the base material and arranged In a comb-tooth shape, and a liquid crystal alignment film formed on the base material so as to cover the linear electrodes.

The FFS substrate, which is a comb electrode substrate used in FFS (fringe Field switching) mode, includes a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, a plurality of line electrodes formed on the insulating film and arranged in a comb-tooth shape, and a liquid crystal alignment film formed on the insulating film so as to cover the line electrodes.

The method for injecting the liquid crystal composition containing the liquid crystal and the radical polymerizable compound is not particularly limited, and examples thereof include: a vacuum method in which the inside of the liquid crystal cell thus produced is depressurized and then a mixture containing a liquid crystal and a polymerizable compound is injected; a dropping method in which a mixture containing a liquid crystal and a polymerizable compound is dropped and then sealed, and the like.

< liquid Crystal composition containing liquid Crystal and radically polymerizable Compound >

In the production of the liquid crystal display element of the present invention, the polymerizable compound used together with the liquid crystal is not particularly limited as long as it is a radical polymerizable compound, and is, for example, a compound having one or two or more polymerizable reactive groups in one molecule. A compound having one polymerizable reactive group in one molecule (hereinafter, sometimes referred to as "a compound having a monofunctional radical polymerizable group") is preferable. The polymerizable reactive group is preferably a radical polymerizable reactive group, for example, a vinyl group.

At least one of the radical polymerizable compounds is preferably a compound having compatibility with the liquid crystal and having one polymerizable reactive group in one molecule, that is, a compound having a monofunctional radical polymerizable group.

The polymerizable group of the radical polymerizable compound is preferably a polymerizable group selected from the following structures.

[ chemical formula 13]

(wherein, represents a bonding site; R^bA linear alkyl group having 2 to 8 carbon atoms, E represents a bonding group selected from the group consisting of a single bond, -O-, -NRc-, -S-, an ester bond and an amide bond; rc represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms).

Further, the liquid crystal composition containing a liquid crystal and a radical polymerizable compound preferably contains a radical polymerizable compound, wherein the polymer obtained by polymerizing the radical polymerizable compound has a Tg of 100 ℃ or lower.

The compound having a monofunctional radical polymerizable group has a reactive group capable of radical polymerization in the presence of an organic radical, and examples thereof include methacrylate monomers such as t-butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, lauryl methacrylate and n-octyl methacrylate; acrylate monomers such as t-butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, benzyl acrylate, lauryl acrylate, and n-octyl acrylate; styrene, styrene derivatives (e.g., o-, m-, p-methoxystyrene, o-, m-, p-t-butoxystyrene, o-, m-, p-chloromethylstyrene, etc.), vinyl esters (e.g., vinyl acetate, vinyl propionate, vinyl benzoate, vinyl acetate, etc.), vinyl ketones (e.g., vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone, etc.), N-vinyl compounds (e.g., N-vinylpyrrolidone, N-vinylpyrrole, N-vinylcarbazole, N-vinylindole, etc.), (meth) acrylic acid derivatives (e.g., acrylonitrile, methacrylonitrile, acrylamide, isopropylacrylamide, methacrylamide, etc.), halogenated ethylenes (e.g., vinyl chloride, vinylidene chloride, tetrachloroethylene, hexachloropentadiene ("hexachloropentadiene" in Japanese, is "ヘキサクロロプレン"), (see FIGS.), Vinyl fluoride, etc.), etc., but are not limited thereto. The various radically polymerizable monomers may be used alone or in combination of 2 or more. Further, it preferably has compatibility with liquid crystal.

Further, as the radical polymerizable compound, a compound represented by the following formula (1) is also preferable.

[ chemical formula 14]

In the formula (1), R^aAnd R^bEach independently represents a linear alkyl group having 2 to 8 carbon atoms, and E represents a bonding group selected from the group consisting of a single bond, -O-, -NRc-, -S-, an ester bond and an amide bond. Wherein Rc represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

In the formula (1), E is preferably an ester bond (-C (═ O) -O-or-O-C (═ O) -) from the viewpoints of ease of synthesis, compatibility with liquid crystals, and polymerization reactivity, and particularly preferably a compound having the following structure, without particular limitation.

[ chemical formula 15]

In the formulas (1-1) and (1-2), Ra and Rb independently represent a linear alkyl group having 2-8 carbon atoms.

The content of the radical polymerizable compound in the liquid crystal composition is preferably 3% by mass or more, more preferably 5% by mass or more, preferably 50% by mass or less, more preferably 20% by mass or less, based on the total mass of the liquid crystal and the radical polymerizable compound.

The Tg of the polymer obtained by polymerizing the radically polymerizable compound is preferably 100 ℃ or lower.

Note that, the liquid crystal generally means: the substance in a state exhibiting both properties of a solid and a liquid includes a nematic liquid crystal and a smectic liquid crystal as typical liquid crystal phases, and the liquid crystal usable in the present invention is not particularly limited. If exemplified, 4-pentyl-4' -cyanobiphenyl.

Next, energy sufficient to cause the radical polymerizable compound to undergo a polymerization reaction is applied to the liquid crystal cell into which the mixture (liquid crystal composition) containing the liquid crystal and the radical polymerizable compound is introduced. This can be performed, for example, by applying heat or UV irradiation, and the radical polymerizable compound is polymerized at that time, thereby exhibiting desired characteristics. Among them, UV irradiation is preferable in that a pattern having orientation can be formed by using UV and a polymerization reaction can be generated in a short time. When the liquid crystal composition is used in a twisted nematic mode, a chiral dopant may be introduced into a liquid crystal cell as needed, in addition to the liquid crystal composition.

In addition, heating may be performed when UV irradiation is performed. The heating temperature in the UV irradiation is preferably within a temperature range in which the introduced liquid crystal exhibits liquid crystallinity, and is usually 40 ℃ or higher, and is preferably lower than a temperature at which the liquid crystal becomes an isotropic phase.

Here, the wavelength of UV irradiation in the case of UV irradiation is preferably selected so as to optimize the quantum yield of the reaction of the polymerizable compound to be reacted, and the dose of UV irradiation is usually 0.01 to 30J/cm²Preferably 10J/cm²Hereinafter, the destruction of the member including the liquid crystal display device can be suppressed when the UV irradiation amount is smallIs preferable because the reliability of (2) is lowered and the tact time in manufacturing is improved by reducing the UV irradiation time.

The heating for polymerization by heating alone without UV irradiation is preferably performed at a temperature at which the polymerizable compound reacts, that is, in a temperature range lower than the decomposition temperature of the liquid crystal. In particular 100-150 ℃.

When sufficient energy is applied to cause the radical polymerizable compound to undergo a polymerization reaction, it is preferably in an electric field-free state without applying a voltage.

< liquid Crystal display element >

The liquid crystal display element can be produced using the liquid crystal cell thus obtained.

For example, a reflective liquid crystal display element can be produced by providing a reflective electrode, a transparent electrode, a λ/4 plate, a polarizing film, a color filter layer, and the like in the liquid crystal cell as needed in a conventional manner.

Further, a backlight, a polarizing plate, a λ/4 plate, a transparent electrode, a polarizing film, a color filter layer, and the like may be provided in the liquid crystal cell as needed in a conventional manner to produce a transmissive liquid crystal display element.

Examples

The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The polymerization of the polymer and the method for evaluating the shorthand notation and the characteristics of the compound used in the preparation of the film-forming composition are shown below.

[ chemical formula 16]

NMP: n-methyl-2-pyrrolidone,

GBL: gamma-butyrolactone,

BCS: butyl cellosolve

< measurement of viscosity >

For the polyamic acid solution, viscosity at 25 ℃ was measured using an E-type viscometer TVE-22H (manufactured by Toyobo industries Co.) in a sample amount of 1.1mL and a Cone Rotor (Cone Rotor) TE-1(1 ℃ 34', R24).

< measurement of molecular weight >

The molecular weight was measured in the following manner using a Gel Permeation Chromatography (GPC) apparatus (GPC-101) (manufactured by SHOWA DENKO CO., LTD.) and a column (KD-803, KD-805) (manufactured by SHOWA DENKO CO., LTD.).

Column temperature: 50 deg.C

Eluent: n, N-dimethylformamide (as additive, lithium bromide monohydrate (LiBr. H)₂O) 30mmol/L (liter), phosphoric acid-anhydrous crystal (orthophosphoric acid) 30mmol/L, Tetrahydrofuran (THF) 10mL/L)

Flow rate: 1.0 mL/min

Standard sample for standard curve preparation: TSK standard polyethylene oxides (molecular weight: about 900000, 150000, 100000 and 30000) (manufactured by Tosoh Corp.) and polyethylene glycols (molecular weight: about 12000, 4000 and 1000) (manufactured by Polymer laboratories, Inc.).

< measurement of imidization Rate >

20mg of polyimide powder was put into an NMR sample tube (NMR sample tube Standard (. phi.5) manufactured by Standykuba, Ltd.), and deuterated dimethyl sulfoxide (DMSO-d) was added₆0.05 mass% TMS (tetramethylsilane) blend) 0.53ml, and ultrasonic waves were applied thereto to completely dissolve the TMS (tetramethylsilane) blend. The 500MHz proton NMR of the solution was measured by a measuring apparatus (JNW-ECA 500, manufactured by DATUM, Japan).

The imidization rate is determined using protons derived from a structure that does not change before and after imidization as reference protons, and is obtained by the following equation using the peak integrated value of the protons and the peak integrated value of the protons derived from NH present in amide groups in the vicinity of 9.5 to 10.0 ppm.

Imidization ratio (%) - (1-. alpha.x/y). times.100

In the formula, x is a peak integrated value of the protons of NH derived from the amide group, y is a peak integrated value of the reference proton, and α is a number ratio of the reference proton to NH protons of 1 amide group in the case of polyamic acid (imidization rate of 0%).

< preparation of Polymer polymerization and radical generating film Forming composition >

Synthesis example 1

Polymerization of TC-1, TC-2(50)/DA-1(50), DA-2(50) polyimides

In a 100mL 4-neck flask equipped with a nitrogen inlet tube, an air condenser tube and a mechanical stirrer, 11.62 g (15.0mmol) of DA and 24.96 g (15.0mmol) of DA were weighed out, 51.9g of NMP was added thereto, and the mixture was stirred under a nitrogen atmosphere to completely dissolve the DA. After confirming the dissolution, TC-23.75 g (15.0mmol) was added, and the mixture was reacted at 60 ℃ for 3 hours under a nitrogen atmosphere. The temperature was again returned to room temperature, and 2.64g (13.5mmol) of TC-1 was added thereto to conduct a reaction at 40 ℃ for 12 hours under a nitrogen atmosphere. The polymerization viscosity was confirmed, and TC-1 was further added so that the polymerization viscosity became about 1000 mPas, to obtain a polymerization solution having a polyamic acid concentration of 20 mass%.

In a 200mL Erlenmeyer flask equipped with a magnetic stirrer, 60g of the polyamic acid solution obtained above was weighed, 111.4g of NMP was added to prepare a solution having a concentration of 7 mass%, 8.38g (81.4mmol) of acetic anhydride and 3.62g (45.8mmol) of pyridine were added while stirring, and after stirring at room temperature for 30 minutes, the reaction was carried out by stirring at 55 ℃ for 3 hours. After completion of the reaction, the solution was returned to room temperature, and the reaction solution was poured into 500mL of methanol with stirring to precipitate a solid. The solid was recovered by filtration, and further, the solid was put into 300ml of methanol 2 times in total, washed with stirring for 30 minutes, and the solid was recovered by filtration, air-dried, and then dried at 60 ℃ using a vacuum oven, whereby polyimide powder (PI-1) having a number average molecular weight (Mn) of 16200, a weight average molecular weight (Mw) of 35200, and an imidization rate of 59% was obtained.

Synthesis example 2

Polymerization of TC-1, TC-2(50)/DA-2(100) polyimides

In a 100mL 4-neck flask equipped with a nitrogen inlet tube, an air condenser tube and a mechanical stirrer, DA-29.91 g (30.0mmol) was measured, and 65.95g of NMP was added thereto and stirred under a nitrogen atmosphere to completely dissolve the compound. After confirming the dissolution, TC-23.75 g (15.0mmol) was added, and the mixture was reacted at 60 ℃ for 3 hours under a nitrogen atmosphere. The temperature was again returned to room temperature, and 2.82g (14.4mmol) of TC-1 was added thereto to conduct reaction at 40 ℃ for 12 hours under a nitrogen atmosphere. The polymerization viscosity was confirmed, and TC-1 was further added so that the polymerization viscosity became about 1000 mPas, to obtain a polymerization solution having a polyamic acid concentration of 20 mass%.

In a 200mL Erlenmeyer flask equipped with a magnetic stirrer, 70g of the polyamic acid solution obtained above was weighed, 130.0g of NMP was added to prepare a solution having a concentration of 7 mass%, 6.90g (67.5mmol) of acetic anhydride and 2.96g (37.4mmol) of pyridine were added while stirring, and after stirring at room temperature for 30 minutes, the mixture was stirred at 55 ℃ for 3 hours to effect a reaction. After completion of the reaction, the solution was returned to room temperature, and the reaction solution was poured into 500mL of methanol with stirring to precipitate a solid. The solid was recovered by filtration, and further, the solid was put into 300ml of methanol 2 times in total, washed with stirring for 30 minutes, and the solid was recovered by filtration, air-dried, and then dried at 60 ℃ using a vacuum oven, whereby polyimide powder (PI-2) having Mn of 18300, Mw of 38900, and imidization rate of 62% was obtained.

Preparation of radical-generating film-forming composition AL-1

In a50 mL Erlenmeyer flask equipped with a magnetic stirrer, 2.0g of the polyimide powder (PI-1) obtained in Synthesis example 1 was weighed, 18.0g of NMP was added, and the mixture was stirred at 50 ℃ to completely dissolve the powder. Further, 6.7g of NMP and 6.7g of BCS were added thereto and stirred for 3 hours, thereby obtaining a radical generating film forming composition of the present invention: AL-1 (solid content: 6.0 mass%, NMP: 74 mass%, BCS: 20 mass%).

Preparation of radical-generating film-forming composition AL-2

In a50 mL Erlenmeyer flask equipped with a magnetic stirrer, 2.0g of the polyimide powder (PI-2) obtained in Synthesis example 2 was weighed, 18.0g of NMP was added, and the mixture was stirred at 50 ℃ to completely dissolve the powder. Further, 6.7g of NMP and 6.7g of BCS were added thereto and stirred for 3 hours, thereby obtaining a radical generating film forming composition of the present invention: AL-2 (solid content: 6.0 mass%, NMP: 74 mass%, BCS: 20 mass%).

A method for manufacturing a liquid crystal cell for evaluating liquid crystal alignment properties is described below.

First, a substrate with electrodes is prepared. The substrate was a glass substrate having a size of 30mm × 35mm and a thickness of 0.7 mm. An IZO electrode having a solid pattern and constituting a counter electrode is formed as a 1 st layer on the substrate. On the counter electrode of the 1 st layer, a SiN (silicon nitride) film formed by a CVD (chemical vapor deposition) method is formed as a 2 nd layer. The SiN film of the 2 nd layer has a film thickness of 500nm and functions as an interlayer insulating film. On the SiN film of the 2 nd layer, a comb-shaped pixel electrode formed by patterning an IZO film is disposed as a 3 rd layer, and two pixels, i.e., a 1 st pixel and a 2 nd pixel, are formed. The size of each pixel was 10mm in length and 5mm in width. At this time, the counter electrode of the 1 st layer and the pixel electrode of the 3 rd layer are electrically insulated by the SiN film of the 2 nd layer.

The pixel electrode of the 3 rd layer has a comb-tooth shape in which a plurality of electrode elements of 3 μm width whose central portion is bent at an inner angle of 160 ° are arranged in parallel at intervals of 6 μm, and 1 pixel has the 1 st region and the 2 nd region bounded by the line connecting the bent portions of the plurality of electrode elements, as in fig. 3 described in japanese patent application laid-open No. 2014-77845 (japanese laid-open patent publication).

The 1 st region and the 2 nd region of each pixel are compared, and the directions of formation of the electrode elements constituting the pixel electrodes are different. That is, when the rubbing direction of the liquid crystal alignment film described later is set as a reference, the electrode element of the pixel electrode is formed to form an angle of +10 ° (clockwise) in the 1 st region of the pixel, and the electrode element of the pixel electrode is formed to form an angle of-10 ° (counterclockwise) in the 2 nd region of the pixel. That is, in the 1 st region and the 2 nd region of each pixel, the directions of the rotation operation (in-plane switching) of the liquid crystal in the substrate plane, which is induced by the voltage application between the pixel electrode and the counter electrode, are opposite to each other. Hereinafter, the FFS substrate (1 st substrate) will be referred to.

Further, as the counter substrate, a glass substrate (hereinafter, referred to as a 2 nd substrate) having an ITO film formed on the back surface and a columnar spacer having a height of 3.3 μm was prepared.

Subsequently, the radical generating film forming composition obtained by the above method or the liquid crystal alignment material Sunover SE-6414 manufactured by Nissan chemical Co., Ltd was filtered through a filter having a pore diameter of 1.0 μm, and then the prepared first substrate 1 and second substrate were coated and formed into a film by spin coating. Subsequently, the film was dried on a hot plate at 80 ℃ for 80 minutes and then sintered at 220 ℃ for 20 minutes to obtain a coating film having a film thickness of 100 nm. The polyimide film on the 1 st substrate side is subjected to rubbing treatment in a direction along the comb tooth direction, and the polyimide film on the 2 nd substrate side is subjected to rubbing treatment in a direction orthogonal to the comb tooth direction of the comb tooth electrode of the 1 st substrate when the 2 nd substrate and the 1 st substrate are arranged to face each other. The cloth used for the rubbing treatment was a rayon cloth produced by the chemical industry of kagawa: YA-20R was rubbed (roll diameter 120 mm). In any case, the substrate coated with SE-6414 was rubbed at a rotation speed of 700rpm, a moving speed of 30mm/sec and an intrusion amount of 0.4mm, and the substrate coated with the radical generating film forming composition was rubbed at a rotation speed of 500rpm, a moving speed of 30mm/sec and an intrusion amount of 0.2 mm. After the rubbing treatment, ultrasonic irradiation was performed in pure water for 1 minute, and drying was performed at 80 ℃ for 10 minutes.

Then, using the above 2 kinds of substrates, it was assumed that a combination of SE-6414 was provided on the 1 st substrate side and a radical generating film was provided on the 2 nd substrate side for the display element targeted for the example. On the other hand, the display device to be compared is a combination of SE-6414 on two substrates, or a combination of SE-6414 on the 1 st substrate and a radical generating film on the 2 nd substrate. In addition, the first substrate and the second substrate were combined so that the rubbing directions thereof were antiparallel to each other, and the periphery was sealed with a liquid crystal injection port, thereby producing a void cell having a cell pitch of about 3.3 μm. In this empty cell, a liquid crystal was injected under vacuum at room temperature (2 mass% of additive IDHex was added to MLC-3019 manufactured by merck corporation), and then the injection port was sealed to prepare an antiparallel aligned liquid crystal cell. The obtained liquid crystal cell constitutes an FFS mode liquid crystal display element. Then, the obtained liquid crystal cell was subjected to heat treatment at 120 ℃ for 10 minutes, and irradiated with UV (UV lamp: FLR40SUV32/A-1) for 30 minutes using a UV-FL irradiation apparatus manufactured by Toshiba Lighting & Technology, in a state where no voltage was applied, to obtain a liquid crystal display element.

< measurement of V-T Curve and evaluation of Driving threshold Voltage and Brightness maximum Voltage >

The V-T curve was measured by mounting a white LED backlight and a luminance meter with the same optical axis, fixing a liquid crystal cell (liquid crystal display element) mounted with a polarizing plate so that the luminance becomes minimum, applying a voltage at 1V intervals up to 8V, and measuring the luminance in the voltage. From the obtained V-T curve, the voltage value at which the driving threshold voltage and the luminance reach the maximum is estimated. The transmission luminance in parallel nicols was defined as 100% through the liquid crystal cell to which no voltage was applied, and the maximum transmission luminance in the V-T curve was compared to determine the maximum transmittance.

< measurement of response time (Ton, Toff) >

In addition to the above measurement, response times Ton and Toff were measured by measuring a temporal change in luminance when a voltage having a maximum luminance was applied and a temporal change in luminance when the voltage was restored to 0V using an oscilloscope.

< evaluation of Voltage Holding Ratio (VHR) >

In a 60 ℃ hot air circulation oven, an alternating pulse voltage with an offset voltage of 0V, an amplitude of 2Vp-p, a frequency of 0.6Hz, and a voltage application time of 60 μ s was applied to the liquid crystal cell, the voltage immediately after the voltage application was released and the voltage (both positive and negative) after 1667ms were measured, and the ratio of the voltage before and after the application was calculated, thereby measuring the Voltage Holding Ratio (VHR). As the measurement apparatus, VHR-1 manufactured by Toyo corporation was used. The higher the VHR the better.

< evaluation of Screen burn-in >

The liquid crystal cell was aged by driving at 60 ℃ for 168 hours in a state where a rectangular wave voltage (60Hz) having the highest luminance was applied to the 1 st region of the pixel and no voltage was applied to the 2 nd region of the other pixel. The luminance of the aged pixel 1 st region and pixel 2 nd region was compared to evaluate burn-in. The case where the luminance ratio is 1.10 or less is defined as "good", and the case where the luminance ratio is more than 1.10 is defined as "bad".

[ Table 1]

< Driving threshold Voltage, maximum luminance Voltage, maximum transmittance, response time >

[ Table 2]

< VHR, burn-in evaluation >

[ Table 3]

Comparative example 1 is the characteristic of the conventional FFS display element using the strongly anchored alignment film, comparative examples 2 and 3 are the characteristic of the FFS display element using the weakly anchored film on the 1 st substrate side, and examples 1 and 2 are the characteristic of the FFS display element using the weakly anchored film on the 2 nd substrate side as the present invention. That is, in examples 1 and 2, the anchoring energy of the liquid crystal alignment film (weak anchor film) on the counter substrate (2 nd substrate) side was smaller than that of the liquid crystal alignment film on the comb-tooth electrode substrate (1 st substrate) side.

The threshold voltage and the maximum luminance voltage of the configurations reported so far, i.e., comparative examples 2 and 3 (in the case of using a weak anchor film on the 1 st substrate side) shifted to a low voltage, and the transmittance also improved along with this, but a tendency was observed to deteriorate the response time. This is considered to be a result of the decrease in anchoring energy on the 1 st substrate side, and it is understood that the anchoring energy is lower in comparative example 3 than in comparative example 2, and the transmittance is improved with this, but the response time tends to be deteriorated. On the other hand, when the weak anchor film is used on the 2 nd substrate side of the present invention, it is found that the transmittance is increased without changing the threshold voltage and the maximum luminance voltage, and the response time is almost the same as that of the conventional FFS display device of comparative example 1. The response time and (driving voltage V-driving threshold voltage V) of the known transverse electric field mode_Th) In inverse proportion, with respect to examples 1 and 2, the driving threshold voltage V_ThAnd a maximum brightness voltage V_maxSince the present invention is also unchanged from the conventional configuration, it is assumed that the configuration of the present invention does not largely affect the response time.

It is also understood that although the conventional weak anchor FFS display elements of comparative examples 2 and 3 have a deteriorated VHR and deteriorated burn-in characteristics compared to the conventional strong anchor FFS display elements, the weak anchor of the present invention improves VHR and provides a satisfactory burn-in characteristic.

Industrial applicability

According to the present invention, a lateral electric field liquid crystal display device capable of realizing high burn-in characteristics (VHR, burn-in characteristics), high backlight transmittance, and high response speed can be provided. The liquid crystal display element obtained by the method of the present invention is useful as a liquid crystal display element of a transverse electric field driving system.

Description of the indicia

1 transverse electric field liquid crystal display element

2 comb electrode substrate

2a base material

2b wire electrode

2c liquid crystal alignment film

2d base material

2e face electrode

2f insulating film

2g wire electrode

2h liquid crystal alignment film

3 liquid crystal

4 opposed substrates

4a liquid crystal alignment film

4b base material

L electric field lines.

Claims

1. A transverse electric field liquid crystal display element comprising:

a comb electrode substrate having a liquid crystal alignment film and a counter substrate having a liquid crystal alignment film, the 2 liquid crystal alignment films being opposed to each other,

the transverse electric field liquid crystal display element is formed by filling liquid crystal between the 2 liquid crystal alignment films, and the anchoring energy of the liquid crystal alignment film on the opposite substrate side is smaller than that of the liquid crystal alignment film on the comb electrode substrate side.

2. The transverse electric field liquid crystal display element according to claim 1,

the liquid crystal alignment film on the comb electrode substrate side and the liquid crystal alignment film on the counter substrate side are both liquid crystal alignment films obtained by uniaxial alignment treatment, and only the liquid crystal alignment film on the counter substrate side is weakly anchored.

3. The transverse electric field liquid crystal display element according to claim 1 or 2,

the comb electrode substrate is an IPS substrate or an FFS substrate.

4. The lateral electric field liquid crystal display element according to any one of claims 1 to 3,

the liquid crystal alignment film on the counter substrate side is: a liquid crystal composition containing the liquid crystal and a radical polymerizable compound, and a radical generating film, wherein the radical polymerizable compound is polymerized in a state of being brought into contact with the radical generating film.

5. The transverse electric field liquid crystal display element according to claim 4,

the radical generating film is a film in which an organic group that induces radical polymerization is immobilized.

6. The transverse electric field liquid crystal display element according to claim 4 or 5,

the radical generating film comprises a polymer containing organic groups that induce radical polymerization.

7. The transverse electric field liquid crystal display element according to claim 6,

the polymer having an organic group which induces radical polymerization is at least one polymer selected from the group consisting of a polyimide precursor obtained using a diamine component containing a diamine having an organic group which induces radical polymerization, a polyimide, a polyurea, and a polyamide.

8. The transverse electric field liquid crystal display element according to claim 6 or 7,

the organic group that induces radical polymerization is an organic group represented by the following structures [ X-1] to [ X-18], [ W ], [ Y ], or [ Z ],

formula [ X-1]～[X-18]In which denotes a bonding site, S₁And S₂Each independently represents-O-, -NR-or-S-, R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and among the alkyl groups having 1 to 10 carbon atoms, the alkyl group having 2 to 10 carbon atoms is-CH₂-part of the radicals being substituted or unsubstituted by oxygen atoms; wherein S is₂In R or NR, in-CH of said alkyl group₂When a part of the radical is substituted by an oxygen atom, said oxygen atom is bonded to S₂Or N is not directly bonded; r¹And R²Each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 4 carbon atoms,

formula [ W ]]、[Y]And [ Z]Wherein Ar represents an aromatic hydrocarbon group selected from the group consisting of phenylene, naphthylene and biphenylene, with or without an organic group and/or a halogen atom as a substituent, and R represents a bonding site, R represents a halogen atom, and⁹and R¹⁰Each independently represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms; at R⁹And R¹⁰When the alkyl group is an alkyl group, the terminal groups may be bonded to each other to form a ring structure or may not be bonded to each other to form a ring structure, and Q represents any of the following structures;

in the formula, R¹¹represents-CH₂-, -NR-, -O-or-S-, R independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and represents a bonding site; s³Represents a single bond, -O-, -NR-or-S-, wherein R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; r¹²Represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms.

9. The transverse electric field liquid crystal display element according to claim 7,

the diamine containing an organic group which induces radical polymerization is a diamine having a structure represented by the following general formula (6) or the following general formula (7),

in the formula (6), R⁶Represents a single bond, -CH₂-、-O-、-COO-、-OCO-、-NHCO-、-CONH-、-NH-、-CH₂O-、-N(CH₃)-、-CON(CH₃) -or-N (CH)₃)CO-，

R⁷Represents a single bond, or an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with a fluorine atom, or any of-CH's of the alkylene groups₂-or-CF₂-1 or more of-are each independently substituted or unsubstituted with a group selected from-CH ═ CH-, a divalent carbocyclic ring and a divalent heterocyclic ring, and further, with or unsubstituted with any of the groups mentioned below, that is, -O-, -COO-, -OCO-, -NHCO-, -CONH-or-NH-being not adjacent to each other;

formula [ X-1]～[X-18]In which denotes a bonding site, S₁And S₂Each independently represents-O-, -NR-or-S-, R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, wherein in the alkyl group having 1 to 10 carbon atoms, the-CH of the alkyl group having 2 to 10 carbon atoms₂-part of the radicals being substituted or unsubstituted by oxygen atoms; wherein S is₂In R or NR, in-CH of said alkyl group₂When a part of the radical is substituted by an oxygen atom, said oxygen atom is bonded to S₂Or N is not directly bonded; r¹And R²Each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 4 carbon atoms;

in the formula (7), T¹And T²Each independently is a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH₂O-、-N(CH₃)-、-CON(CH₃) -or-N (CH)₃)CO-，

S represents a single bond, or an alkylene group having 1 to 20 carbon atoms which is unsubstituted or substituted with a fluorine atom, or any of-CH' S of the alkylene groups₂-or-CF₂1 or more of-are each independently substituted or unsubstituted with a group selected from-CH- ═ CH-, a divalent carbocyclic ring and a divalent heterocyclic ring, and further, with or unsubstituted with any of the groups mentioned below, that is, with-O-, -COO-, -OCO-, -NHCO-, -CONH-or-NH-not adjacent to each other,

j is an organic group represented by a formula selected from the group consisting of [ W ], [ Y ] and [ Z ] below;

formula [ W ]]、[Y]And [ Z]In the formula, represents and T²Ar represents an aromatic hydrocarbon group selected from the group consisting of phenylene, naphthylene and biphenylene, with or without an organic group and/or a halogen atom as a substituent, R⁹And R¹⁰Each independently represents an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms,

q represents any one of the following structures;

in the formula, R¹¹represents-CH₂-, -NR-, -O-or-S-, R independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and represents a bonding site;

S³represents a single bond, -O-, -NR-, or-S-, wherein R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

10. The lateral electric field liquid crystal display element according to any one of claims 4 to 9,

at least one of the radical polymerizable compounds is a compound having compatibility with a liquid crystal and having one polymerizable reactive group in one molecule.

11. The transverse electric field liquid crystal display element according to claim 10,

the polymerizable reactive group of the radical polymerizable compound is selected from the following structures,

wherein, represents a bonding site; r^bA linear alkyl group having 2 to 8 carbon atoms, E represents a bonding group selected from the group consisting of a single bond, -O-, -NRc-, -S-, an ester bond and an amide bond; rc represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

12. The transverse electric field liquid crystal display element according to any one of claims 4 to 11, wherein the radically polymerizable compound is a radically polymerizable compound in which a polymer obtained by polymerizing the radically polymerizable compound has a Tg of 100 ℃ or less.

13. A method of fabricating a lateral electric field liquid crystal cell, comprising:

preparing a first substrate having a liquid crystal alignment film, i.e., a comb-teeth electrode substrate, and a second substrate having a radical generating film, i.e., a counter substrate,

a step of fabricating a cell in such a manner that the radical generating film on the second substrate is opposed to the first substrate, an

14. The method of manufacturing a lateral electric field liquid crystal cell according to claim 13,

the second substrate is a substrate coated with a liquid crystal alignment film having uniaxial alignment properties.

15. The method of manufacturing a transverse electric field liquid crystal cell according to claim 14,

the liquid crystal alignment film having uniaxial alignment is a liquid crystal alignment film for horizontal alignment.

16. The method of manufacturing a lateral electric field liquid crystal cell according to any one of claims 13 to 15, wherein the comb-teeth electrode substrate is an IPS substrate or an FFS substrate.