TWI846705B - Method for producing zero plane anchoring film, and liquid crystal display element - Google Patents

Abstract

An object of the invention is to provide an industrial method for producing a zero plane anchoring film, a favorable liquid crystal display element that uses this film, and a method for producing the liquid crystal display element. The method for producing the patterned zero plane anchoring film of the invention includes a step of forming a patterned radical generating film by irradiating radiation onto a specific area of a radical generating film, and a step of applying sufficient energy to a liquid crystal composition containing a liquid crystal and a radical polymerizable compound to induce a polymerization reaction of the radical polymerizable compound, while the liquid crystal composition is in contact with the patterned radical generating film. Furthermore, a method for creating a functional film includes a step of preparing a cell which has a liquid crystal composition containing a liquid crystal and a radical polymerizable compound sandwiched between a first substrate that has a radical generating film and a second substrate that does not have a radical generating film, and a step of applying sufficient energy to the cell to induce a polymerization reaction of the radical polymerizable compound.

Description

Method for manufacturing zero-surface anchor film and liquid crystal display element

The present invention relates to a manufacturing method using polymer stabilization technology to manufacture a zero-surface anchor film at a low cost and without complicated steps, and a liquid crystal display element and a manufacturing method thereof that uses the manufacturing method to achieve a lower voltage drive.

In recent years, liquid crystal display elements have been widely used in mobile phones, computers, and television displays. Liquid crystal display elements have the characteristics of being thin, light, and low in power consumption. In the future, they are expected to be applied to VR, ultra-high-precision displays, and other further contents. A variety of display modes have been proposed for liquid crystal displays, such as TN (Twisted Nematic), IPS (In-Plane Switching), and VA (Vertical Alignment). All modes use a film (liquid crystal alignment film) that induces the liquid crystal to the desired alignment state.

In particular, tablet PCs, smart phones, smart TVs and other products with touch panels prefer to use IPS mode, which does not easily disturb the display even when touched. In recent years, in order to improve contrast and viewing angle characteristics, liquid crystal display elements using FFS (Fringe Field Switching) and non-contact technology using optical alignment have gradually been adopted.

However, compared to IPS, FFS has a higher manufacturing cost for the substrate, and the problem of display defects unique to the FFS mode, called Vcom offset, occurs. In addition, compared to the friction method, the size of the manufactured components can be increased and the display characteristics are greatly improved, but there are problems in the principle of photo-alignment (if it is a decomposition type, there will be display defects caused by decomposition products, and if it is anisotropic type, there will be burns caused by insufficient alignment force, etc.). In order to solve these problems, LCD display component manufacturers and LCD alignment film manufacturers have made various efforts.

On the other hand, in recent years, an IPS mode using zero-surface anchoring has been proposed. By using this method, it is reported that the contrast can be improved and the driving voltage can be significantly reduced compared to the conventional IPS mode (see patent document 1).

Specifically, a liquid crystal alignment film with strong anchoring energy is used on one side of the substrate, and a treatment is applied to the substrate side having an electrode for generating a lateral electric field so as to completely eliminate the alignment constraint force of the liquid crystal, thereby manufacturing a liquid crystal display element of the IPS mode.

In recent years, some people have used thick polymer brushes to produce a zero-plane state, and proposed a technical proposal for a zero-plane anchored IPS mode (reference document 2). This technology has achieved a significant improvement in contrast ratio and a significant reduction in driving voltage. On the other hand, there is a problem of a significant decrease in response speed, especially when the voltage is OFF. This is caused by the influence of a weaker electric field response than the usual driving method due to the lower driving voltage, and the extremely small anchoring force of the alignment film, which causes the liquid crystal to take a long time to recover. As a solution, some people have proposed a method of achieving zero anchoring only on the pixel electrode (patent document 3). Some people report that this can take into account both brightness improvement and response speed. [Previous technical document] [Patent document]

[Patent Document 1] Japanese Patent Publication No. 4053530 [Patent Document 2] Japanese Patent Publication No. 2013-231757 [Patent Document 3] Japanese Patent Publication No. 2017-211566

(The problem to be solved by the invention)

By achieving zero-surface anchoring only on the electrodes of the IPS comb electrodes, the response speed delay during driving can be suppressed. However, since only the electrodes are zero-anchored, it is necessary to prepare difficult technologies such as coating different materials separately in very small areas, which will become a major issue in actual industrialization. If such technical issues can be solved, it will have significant cost benefits for panel manufacturers, and it is also believed to have benefits in terms of battery power consumption suppression and image quality improvement. This invention is to solve the above-mentioned problems, and its purpose is to provide a method for making zero-surface anchoring parts and parts with anchoring force in the plane of the liquid crystal alignment film, and a method for controlling the anchoring energy to an arbitrary state, and to achieve non-contact alignment, low driving voltage, and accelerated response speed when off at room temperature in a simple and low-cost method. A lateral electric field liquid crystal display element and its manufacturing method. (Method for solving the problem)

The inventors of this case have made great efforts to study and find that the above problems can be solved, and have completed the present invention with the following gist.

That is, the present invention includes the following. [1] A method for manufacturing a patterned zero-plane anchor film, comprising the following steps: irradiating a free radical generating film in a specific area with radiation to form a patterned free radical generating film; and bringing a liquid crystal composition containing a liquid crystal and a free radical polymerizable compound into contact with the patterned free radical generating film and, while maintaining this state, providing the liquid crystal composition with sufficient energy for the free radical polymerizable compound to undergo a polymerization reaction. [2] A method for manufacturing a patterned zero-plane anchor film as in [1], wherein the free radical generating film is a free radical generating film that has been subjected to a uniaxial alignment treatment. [3] A method for manufacturing a patterned zero-plane anchor film as in [1] or [2], wherein the step of providing energy is performed in the absence of an electric field. [4] A method for producing a patterned zero-surface anchor film as described in any one of [1] to [3], wherein the free radical generating film is a film formed by fixing an organic group that induces free radical polymerization. [5] A method for producing a patterned zero-surface anchor film as described in any one of [1] to [3], wherein the free radical generating film is obtained by coating and curing a composition of a compound having a group that generates free radicals and a polymer to form a film so as to fix the group in the film. [6] A method for producing a patterned zero-surface anchor film as described in any one of [1] to [3], wherein the free radical generating film is composed of a polymer containing an organic group that induces free radical polymerization. [7] A method for producing a patterned zero-surface anchor film as described in [6], wherein the polymer containing an organic group that induces free radical polymerization is at least one polymer selected from a polyimide precursor, polyimide, polyurea and polyamide obtained by using a diamine component containing a diamine containing an organic group that induces free radical polymerization. [8] A method for producing a patterned zero-surface anchor film as described in any one of [4], [6] and [7], wherein the organic group that induces free radical polymerization is an organic group represented by any one of the following structures [X-1] to [X-18], [W], [Y] and [Z]; [Chemical 1] In formulas [X-1] to [X-18], * represents a bonding site other than a polymerizable unsaturated bond with a compound molecule, S ₁ and S ₂ each independently represent -O-, -NR-, or -S-, R represents 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, and R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms; [Chemical 2] In the formulas [W], [Y], and [Z], * represents a bonding site other than a polymerizable unsaturated bond with a compound molecule, Ar 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, ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and when ^R9 and ^R10 are alkyl groups, the terminals may also be bonded to each other to form a ring structure; Q represents the following structure: [Chemical 3] In the formula, R ¹¹ represents -CH ₂ -, -NR-, -O-, or -S-, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, * represents a bonding site with a portion other than Q of the compound molecule; R ₁₂ represents 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 method for producing a patterned zero-surface anchor film as described in [7], wherein the diamine containing an organic group that induces free radical polymerization is a diamine having a structure represented by the following general formula (6) or the following general formula (7); [Chemical 4] In formula (6), R ⁶ represents a single bond, -CH ₂ -, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-, R ⁷ represents a single bond, or an unsubstituted or fluorine-substituted alkylene group having 1 to 20 carbon atoms, wherein any one or more of -CH ₂ - or -CF ₂ - in the alkylene group may be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring, and may be replaced by any of the following groups, i.e., -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH-, provided that the groups are not adjacent to each other; R ⁸ represents a free radical polymerization reactive group selected from the following formula: [Chemical 5] In formulas [X-1] to [X-18], * represents a bonding site with a portion other than a radical polymerization reactive group of a compound molecule, S ₁ and S ₂ each independently represent -O-, -NR-, or -S-, R represents 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, and R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms; [Chemical 6] In formula (7), _T1 and _T2 are each independently a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH- _, -NH-, -CH2O-, -N(CH3)-, -CON( _CH3 )-, or -N( _{CH3 )} CO-; ^S0 represents a single bond, or an unsubstituted or fluorine-substituted alkylene group having 1 to 20 carbon atoms; any one or more of _-CH2- or _-CF2- in the alkylene group may be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring; further, any one of the following groups, i.e., -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH- may be replaced by these groups provided that they are not adjacent to each other. J is an organic group represented by any of the following formulas, [Chemical 7] In the formulas [W], [Y], and [Z], * represents a bonding site with _T2 , Ar 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, ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and Q represents any of the following structures: [Chemical 8] In the formula, R ¹¹ represents -CH ₂ -, -NR-, -O-, or -S-, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, * represents a bonding site with a portion other than Q of the compound molecule; R ₁₂ represents 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. [10] A method for producing a patterned zero-surface anchor film as described in any one of [1] to [9], wherein at least one of the free radical polymerizable compounds is a compound having one polymerizable unsaturated bond in one molecule that is compatible with liquid crystal. [11] A method for producing a patterned zero-surface anchor film as described in [10], wherein the polymerizable group of the free radical polymerizable compound is selected from the following structures; [Chemical 9] In the formula, * represents a bonding site with a portion other than a polymerizable unsaturated bond of a compound molecule; ^Rb represents a linear alkyl group having 2 to 8 carbon atoms; E represents a bonding group selected from a single bond, -O-, ^-NRc- , -S-, an ester bond, and an amide bond; and ^Rc represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. [12] A method for producing a patterned zero-surface anchor film as described in any one of [1] to [11], wherein the liquid crystal composition containing a liquid crystal and a radically polymerizable compound contains a radically polymerizable compound that allows the polymer obtained by polymerizing the radically polymerizable compound to have a Tg of 100°C or less. [13] A method for manufacturing a liquid crystal cell, using a method for manufacturing a patterned zero-surface anchoring film as described in any one of [1] to [12], comprising the following steps: preparing a first substrate having a free radical generating film and a second substrate which may also have a free radical generating film; manufacturing a cell in a manner such that the free radical generating film on the first substrate faces the second substrate; and filling a liquid crystal composition containing liquid crystal and a free radical polymerizable compound between the first substrate and the second substrate. [14] A method for manufacturing a liquid crystal cell as described in [13], wherein the second substrate is a second substrate without a free radical generating film. [15] A method for manufacturing a liquid crystal cell as described in [14], wherein the second substrate is coated with a liquid crystal alignment film having a uniaxial alignment property. [16] A method for manufacturing a liquid crystal cell as described in [15], wherein the liquid crystal alignment film having a uniaxial alignment property is a liquid crystal alignment film for horizontal alignment. [17] A method for manufacturing a liquid crystal cell as described in any one of [13] to [16], wherein the first substrate having a free radical generating film is a substrate having a comb electrode. [18] A liquid crystal composition comprising a liquid crystal and a free radical polymerizable compound, at least one of the free radical polymerizable compounds is a compound having one polymerizable unsaturated bond in one molecule that is compatible with the liquid crystal, and the polymerizable group is selected from the following structures: [Chemical 10] In the formula, * represents a bonding site with a portion other than a polymerizable unsaturated bond of a compound molecule; ^Rb represents a straight chain alkyl group having 2 to 8 carbon atoms; E represents a bonding group selected from a single bond, -O-, ^-NRc- , -S-, an ester bond, and an amide bond; ^Rc represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms. [19] A method for manufacturing a liquid crystal display element, using a film in a zero-face anchoring state obtained using any of the methods of [1] to [17]. [20] A liquid crystal display element obtained using the method for manufacturing a liquid crystal display element as described in [19]. [21] A liquid crystal display element as described in [20], wherein the first substrate or the second substrate has an electrode. [22] The liquid crystal display element as described in [20] or [21] is a low voltage driven transverse electric field liquid crystal display element. (Effects of the invention)

According to the present invention, a zero-surface anchor film can be manufactured industrially with a good yield. Using the method of the present invention, a liquid crystal display element similar to the zero-surface anchor IPS mode liquid crystal display element described in Patent Documents 1 and 2 can be manufactured simply with low-cost raw materials and existing manufacturing methods. In addition, the liquid crystal display element obtained by the manufacturing method of the present invention can provide a liquid crystal display element with excellent characteristics such as a faster response speed of the liquid crystal when Off, a low driving voltage, no bright spots, the ability to suppress Vcom offset in IPS mode, and higher precision in FFS mode compared to the known technology.

The present invention is a method for manufacturing a film with zero-surface anchoring and strong anchoring regions, which is characterized by forming a free radical generating film with anchoring force on a substrate and irradiating the free radical generating film with radiation in the region where the anchoring force is to be maintained, so that the free radical generating film contacts a liquid crystal containing a specific polymerizable compound, and the polymerizable compound is polymerized by UV or heat. More specifically, it is a method for manufacturing a film with zero-surface anchoring and strong anchoring regions, which includes the following steps: preparing a unit cell having a liquid crystal composition containing liquid crystal and a free radical polymerizable compound between a first substrate having a free radical generating film treated with radiation and a second substrate which may also have a free radical generating film; and providing the unit cell with sufficient energy for the free radical polymerizable compound to undergo a polymerization reaction. Preferably, a method for manufacturing a liquid crystal cell comprises the following steps: preparing a first substrate having a free radical generating film treated by radiation and a second substrate having no free radical generating film; manufacturing a cell in a manner that the free radical generating film faces the second substrate; and filling a liquid crystal composition containing liquid crystal and a free radical polymerizable compound between the first substrate and the second substrate. For example, in a method for manufacturing a low voltage driven IPS liquid crystal display element, the second substrate has no free radical generating film and is a substrate having a liquid crystal alignment film treated by uniaxial alignment, and the first substrate is a substrate having a comb electrode.

In the present invention, "zero-plane anchor film" refers to a film that has no alignment constraint force on the liquid crystal molecules in the in-plane direction, or even if it has, it is weaker than the intermolecular force between the liquid crystals, and this film alone cannot uniaxially align the liquid crystal molecules in any direction. In addition, this zero-plane anchor film is not limited to a solid film, but also includes a liquid film covering a solid surface. Usually, in a liquid crystal display element, a film that constrains the alignment of the liquid crystal molecules, that is, a liquid crystal alignment film, is used in pairs to align the liquid crystal, but the zero-plane anchor film and the liquid crystal alignment film can also be used in pairs to align the liquid crystal. The reason is that the alignment constraint force of the liquid crystal alignment film will be transmitted to the thickness direction of the liquid crystal layer through the intermolecular force between the liquid crystal molecules, resulting in that the liquid crystal molecules close to the zero-plane anchor film are also aligned. Therefore, when the liquid crystal alignment film is used for horizontal alignment, the entire liquid crystal cell can be aligned horizontally. Horizontal alignment refers to the state in which the long axes of the liquid crystal molecules are roughly arranged parallel to the surface of the liquid crystal alignment film. Even if there is a tilted alignment of about several degrees, it is also included in the scope of horizontal alignment.

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

The organic group that induces free radical polymerization may be an organic group represented by any one of [X-1] to [X-18], [W], [Y] and [Z] represented by the following structures. [Chemical 11] In formulas [X-1] to [X-18], * represents a bonding site other than a polymerizable unsaturated bond with a compound molecule, _S1 and _S2 each independently represent -O-, -NR-, or -S-, R represents 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, and _R1 and _R2 each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. [Chemistry 12] In formulas [W], [Y], and [Z], * represents a bonding site other than a polymerizable unsaturated bond with a compound molecule, Ar 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, ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and when ^R9 and ^R10 are alkyl groups, the terminals may also be bonded to each other to form a ring structure. Q represents any of the following structures. [Chemistry 13] In the formula, R ¹¹ represents -CH ₂ -, -NR-, -O-, or -S-, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and * represents a bonding site with a part other than Q of the compound molecule. R ₁₂ represents 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.

The polymer is preferably a polyimide precursor, and at least one polymer selected from the group consisting of polyimide, polyurea, polyamide, polyacrylate, polymethacrylate, polyorganosiloxane, etc.

In order to obtain the free radical generating film used in the present invention, when using the aforementioned polymer having an organic group that induces free radical polymerization, in order to obtain a polymer having a group that can generate free radicals, as for the monomer components, it is preferred to use a monomer having a photoreactive side chain containing at least one selected from methacrylic acid, acrylic acid, vinyl, allyl, coumarin, styryl and cinnamyl groups, and a monomer having a side chain having a site that is decomposed by ultraviolet irradiation and generates free radicals. On the other hand, considering the problem that the monomers generating free radicals themselves will spontaneously polymerize and become unstable compounds, it is more desirable to use a polymer derived from a diamine having a free radical generating site from the viewpoint of ease of synthesis, and more preferably a polyimide precursor such as polyamic acid, polyamic acid ester, polyimide, polyurea, polyamide, etc.

Such a diamine containing a free radical generating site is specifically, for example, a diamine having a side chain capable of generating free radicals and polymerizing, such as the diamine represented by the following general formula (6) but not limited thereto. [Chemistry 14] In formula (6), R ⁶ represents a single bond, -CH ₂ -, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-; R ⁷ represents a single bond, or an unsubstituted or fluorine-substituted alkylene group having 1 to 20 carbon atoms, wherein any one or more of -CH ₂ - or -CF ₂ - in the alkylene group may be independently substituted with a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring; and may be substituted with any of the following groups, i.e., -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH-, provided that the groups are not adjacent to each other; R ⁸ , represents a free radical polymerization reactive group selected from the following formula: [Chemistry 15] In formulae [X-1] to [X-18], * represents a bonding site with a portion other than a radical polymerization reactive group of a compound molecule, S ₁ and S ₂ each independently represent -O-, -NR-, or -S-, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ₁₂ represents 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, and R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.

In formula (6), the bonding positions of the two amino groups (-NH ₂ ) are not limited. Specifically, the bonding positions relative to the side chain are 2,3 position, 2,4 position, 2,5 position, 2,6 position, 3,4 position, 3,5 position on the benzene ring. Among them, considering the reactivity when synthesizing polyamide, 2,4 position, 2,5 position, or 3,5 position is preferred. If the ease of synthesizing diamine is also considered, 2,4 position or 3,5 position is more ideal.

As the diamine having a photoreactive group containing at least one selected from the group consisting of a methacrylic group, an acrylic group, a vinyl group, an allyl group, a coumarin group, a styryl group, and a cinnamyl group, specifically, the following compounds can be cited, but are not limited thereto. [Chemical 16] In the formula, ^J1 represents a bonding group selected from a single bond, -O-, -COO-, -NHCO-, or -NH-, and ^J2 represents a single bond, or an unsubstituted or fluorine-substituted alkylene group having 1 to 20 carbon atoms.

As the diamine having a site as a side chain that decomposes and generates free radicals by ultraviolet irradiation, the diamine represented by the following general formula (7) can be cited, but is not limited thereto. [Chemical 17] In formula (7), _T1 and _T2 are each independently a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH- _, -NH-, -CH2O-, -N(CH3)-, -CON( _CH3 )-, or -N( _{CH3 )} CO-; ^S0 represents a single bond, or an unsubstituted or fluorine-substituted alkylene group having 1 to 20 carbon atoms; any one or more of _-CH2- or _-CF2- in the alkylene group may be independently substituted with a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring; and may be substituted with any of the following groups, i.e., -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH-, provided that the groups are not adjacent to each other. J is an organic group represented by any of the following formulas: In formula [W], [Y], [Z], * represents the bonding site with _T2 , Ar 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, ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and Q represents any of the following structures. [Chemical 19] In the formula, R ¹¹ represents -CH ₂ -, -NR-, -O-, or -S-, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and * represents a bonding site with a part other than Q of the compound molecule. R ₁₂ represents 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.

The bonding positions of the two amino groups (-NH ₂ ) in the above formula (7) are not limited. Specifically, the bonding groups relative to the side chains are 2,3 positions, 2,4 positions, 2,5 positions, 2,6 positions, 3,4 positions, and 3,5 positions on the benzene ring. Among them, considering the reactivity when synthesizing polyamide, 2,4 positions, 2,5 positions, or 3,5 positions are preferred. If the ease of synthesizing diamine is also considered, 2,4 positions or 3,5 positions are more ideal.

In particular, considering the ease of synthesis, high versatility, characteristics, etc., the structure represented by any of the following formulas is most ideal, but is not limited to these. [Chemical 20] Where n is an integer between 2 and 8.

The above diamines may be used alone or in combination of two or more, depending on the liquid crystal orientation when the radical generation film is prepared, the sensitivity in the polymerization reaction, the voltage holding property, the stored charge and other properties.

Such a diamine having a free radical polymerization site is preferably used in an amount of 5 to 50 mol %, more preferably 10 to 40 mol %, and even more preferably 15 to 30 mol % of the total diamine component used in the synthesis of the polymer contained in the free radical film-forming composition.

Furthermore, when the polymer used in the free radical generating film of the present invention is obtained from diamine, other diamines other than the above diamines having a free radical generating site may be used as diamine components as long as the effect of the present invention is not impeded. Specifically, for example, p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminobiphenyl, 3,3' -dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3,3'-dicarboxy-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-biphenyl, 3,3'-trifluoromethyl-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 4 ,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3'-diaminodiphenyl ether, 4,4'-sulfonyldiphenylamine, 3,3'-sulfonyldiphenylamine, bis(4-aminodiphenylamine) phenyl) silane, bis(3-aminophenyl) silane, dimethyl-bis(4-aminophenyl) silane, dimethyl-bis(3-aminophenyl) silane, 4,4'-diaminodiphenylamine, 3,3'-diaminodiphenylamine, 4,4'-diaminodiphenylamine, 3,3'-diaminodiphenylamine, 3,4'-diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, N-methyl(4,4'-diaminodiphenyl)amine, N-methyl(3,3'- diaminodiphenyl)amine, N-methyl(3,4'-diaminodiphenyl)amine, N-methyl(2,2'-diaminodiphenyl)amine, N-methyl(2,3'-diaminodiphenyl)amine, 4,4'-diaminodiphenyl ketone, 3,3'-diaminodiphenyl ketone, 3,4'-diaminodiphenyl ketone, 1,4-diaminonaphthalene, 2,2'-diaminodiphenyl ketone, 2,3'-diaminodiphenyl ketone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1 ,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis(4-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, 4,4'-[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, 3,3’-[1,4-phenylenebis(methylene)]diphenylamine, 3,3’-[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) ketone], 1,4-phenylene bis(4-aminobenzoate), 1,4-phenylene bis(3-aminobenzoate), 1,3-phenylene bis(4-aminobenzoate), 1,3-phenylene bis(3-aminobenzoate), bis(4-aminophenyl) terephthalate, bis(3-aminophenyl) terephthalate, bis(4-aminophenyl) isophthalate, bis(3-aminophenyl) isophthalate, N,N'-(1 ,4-phenylene)bis(4-aminobenzamide), N,N’-(1,3-phenylene)bis(4-aminobenzamide), N,N’-(1,4-phenylene)bis(3-aminobenzamide), N,N’-(1,3-phenylene)bis(3-aminobenzamide), N,N’-bis(4-aminophenyl)-p-phenylenediamide, N,N’-bis(3-aminophenyl)-p-phenylenediamide, N,N’-bis(4-aminophenyl)-m-phenylenediamide 、N,N'-bis(3-aminophenyl)m-xylylenediamide、9,10-bis(4-aminophenyl)anthracene、4,4'-bis(4-aminophenoxy)diphenylsulfone、2,2'-bis[4-(4-aminophenoxy)phenyl]propane、2,2'-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane、2,2'-bis(4-aminophenyl)hexafluoropropane、2,2'-bis(3-aminophenyl)hexafluoropropane、2,2'-bis(3-aminophenyl)hexafluoropropane -methylphenyl) hexafluoropropane, 2,2'-bis(4-aminophenyl)propane, 2,2'-bis(3-aminophenyl)propane, 2,2'-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, 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) 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, 1,12-Bis(4-aminophenoxy)dodecane, 1,12-Bis(3-aminophenoxy) -aminophenoxy) dodecane and other aromatic diamines; bis(4-aminocyclohexyl)methane, bis(4-amino-3-methylcyclohexyl)methane and other alicyclic diamines; 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, etc. Aliphatic diamines; diamines with urea structure such as 1,3-bis[2-(p-aminophenyl)ethyl]urea and 1,3-bis[2-(p-aminophenyl)ethyl]-1-tert-butoxycarbonylurea; diamines with nitrogen-containing unsaturated heterocyclic structure such as N-p-aminophenyl-4-p-aminophenyl(tert-butoxycarbonyl)aminomethylpiperidine; diamines with N-Boc group such as N-tert-butoxycarbonyl-N-(2-(4-aminophenyl)ethyl)-N-(4-aminobenzyl)amine, etc.

The above other diamines may be used alone or in combination of two or more, depending on the liquid crystal orientation when the free radical generation film is prepared, the sensitivity in the polymerization reaction, the voltage holding property, the stored charge and other properties.

When the polymer is polyamide, the tetracarboxylic dianhydride to be reacted with the diamine component is not particularly limited. Specifically, pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7-anthracenetetracarboxylic acid, 1,2,5,6-anthracenetetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, 2,3,3',4'-biphenyltetracarboxylic acid, bis(3,4-dicarboxyphenyl)ether, 3,3',4,4'-diphenylketonetetracarboxylic acid, bis(3,4-dicarboxyphenyl)sulfone, bis(3,4-dicarboxyphenyl)methane, 2,2-bis(3,4-dicarboxyphenyl)propane, 1,1,1,3,3,3-hexafluoro-2,2-bis(3,4-dicarboxyphenyl)propane , bis(3,4-dicarboxyphenyl)dimethylsilane, bis(3,4-dicarboxyphenyl)diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis(3,4-dicarboxyphenyl)pyridine, 3,3',4,4'-diphenylsulfonatetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid, 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic acid, oxydiphthalidetetracarboxylic 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 tetracarboxylic acid, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cycloheptanetetracarboxylic acid, 2,3,4,5-tetrahydrofurantetracarboxylic acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid, bicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic acid, bicyclo[4,3,0]nonane-2,4,7,9-tetracarboxylic acid, bicyclo[4,4,0]decane-2,4,7,9-tetracarboxylic acid, bicyclo[4,4,0]decane-2,4,8,10-tetracarboxylic acid, tricyclo[6.3.0. Dianhydrides of tetracarboxylic acids such as 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-dioxotetrahydrofuranyl)-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, and 1,2,4,5-cyclohexanetetracarboxylic acid.

Of course, the tetracarboxylic dianhydride may be used alone or in combination of two or more depending on the liquid crystal orientation when the radical generating film is prepared, the sensitivity in the polymerization reaction, the voltage holding property, the stored charge and other properties.

In the synthesis of a polymer of polyamic acid ester, the structure of the tetracarboxylic acid dialkyl ester reacted with the above-mentioned diamine component is not particularly limited, and specific examples thereof are given below. Specific examples of aliphatic tetracarboxylic acid diesters include 1,2,3,4-cyclobutane tetracarboxylic acid dialkyl ester, 1,2-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid dialkyl ester, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid dialkyl ester, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic acid dialkyl ester, 1,2,3,4 -cyclopentane tetracarboxylic acid dialkyl ester, 2,3,4,5-tetrahydrofuran tetracarboxylic acid dialkyl ester, 1,2,4,5-cyclohexane tetracarboxylic acid dialkyl ester, 3,4-dicarboxy-1-cyclohexyl succinic acid dialkyl ester, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid dialkyl ester, 1,2,3,4-butane tetracarboxylic acid dialkyl ester, bicyclo[3,3,0]octane -2,4,6,8-tetracarboxylic acid dialkyl ester, 3,3',4,4'-dicyclohexyltetracarboxylic acid dialkyl ester, 2,3,5-tricarboxycyclopentylacetic acid dialkyl ester, cis-3,7-dibutylcyclooctane-1,5-diene-1,2,5,6-tetracarboxylic acid dialkyl ester, tricyclo[4.2.1.0＜2,5＞]nonane-3,4,7,8-tetracarboxylic acid-3,4: 7,8-dialkyl ester, hexacyclo[6.6.0.1＜2,7＞.0＜3,6＞.1＜9,14＞.0＜10,13＞]hexadecane-4,5,11,12-tetracarboxylic acid-4,5:11,12-dialkyl ester, 4-(2,5-dioxytetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid dialkyl ester, and the like.

Examples of the aromatic tetracarboxylic acid dialkyl esters include pyromellitic acid dialkyl esters, 3,3',4,4'-biphenyltetracarboxylic acid dialkyl esters, 2,2',3,3'-biphenyltetracarboxylic acid dialkyl esters, 2,3,3',4-biphenyltetracarboxylic acid dialkyl esters, 3,3',4,4'-diphenyl ketonetetracarboxylic acid dialkyl esters, 2,3,3',4'-diphenyl ketonetetracarboxylic acid dialkyl esters, bis(3,4-dicarboxyphenyl)ether dialkyl esters, bis(3,4-dicarboxyphenyl)sulfone dialkyl esters, 1,2,5,6-naphthalenetetracarboxylic acid dialkyl esters, and 2,3,6,7-naphthalenetetracarboxylic acid dialkyl esters.

In the synthesis of a polymer of polyurea, the diisocyanate to be reacted with the diamine component is not particularly limited, and can be used in accordance with availability, etc. The specific structure of the diisocyanate is shown below. [Chemical 21] In the formula, R ₂ and R ₃ represent aliphatic hydrocarbons having 1 to 10 carbon atoms.

Aliphatic diisocyanates shown in K-1~K-5 have poor reactivity but have the advantage of better solvent solubility. Aromatic diisocyanates shown in K-6~K-7 are highly reactive and have the effect of improving heat resistance, but have the disadvantage of low solvent solubility. Considering the versatility and characteristics, K-1, K-7, K-8, K-9, and K-10 are particularly preferred. Considering the electrical characteristics, K-12 is more ideal. From the perspective of liquid crystal alignment, K-13 is particularly preferred. More than one diisocyanate can be used in combination, and it is better to use it according to the desired characteristics. Furthermore, a part of the diisocyanate may be replaced with the above-described tetracarboxylic dianhydride, and the product may be used in the form of a copolymer of polyamide and polyurea, or in the form of a copolymer of polyimide and polyurea by chemical imidization.

In the synthesis of the polymer being polyamide, the structure of the dicarboxylic acid to be reacted is not particularly limited, and specific examples thereof are listed below. Specific examples of aliphatic dicarboxylic acids include malonic acid, oxalic acid, dimethylmalonic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, muconic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid, and suberic acid.

Examples of alicyclic dicarboxylic acids include 1,1-cyclopropanedicarboxylic acid, 1,2-cyclopropanedicarboxylic acid, 1,1-cyclobutanedicarboxylic acid, 1,2-cyclobutanedicarboxylic acid, 1,3-cyclobutanedicarboxylic acid, 3,4-diphenyl-1,2-cyclobutanedicarboxylic acid, 2,4-diphenyl-1,3-cyclobutanedicarboxylic acid, 1-cyclobutene-1,2-dicarboxylic acid, 1-cyclobutene-3,4-dicarboxylic acid, 1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,1-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, dicarboxylic acids, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,4-(2-norbornene)dicarboxylic acid, norbornene-2,3-dicarboxylic acid, bicyclo[2.2.2]octane-1,4-dicarboxylic acid, bicyclo[2.2.2]octane-2,3-dicarboxylic acid, 2,5-dihydroxy-1,4-bicyclo[2.2.2]octanedicarboxylic acid, 1,3-adamantanedicarboxylic acid, 4,8-dihydroxy-1,3-adamantanedicarboxylic acid, 2,6-spiro[3.3]heptanedicarboxylic acid, 1,3-adamantanedicarboxylic acid, camphoric acid, and the like.

Aromatic dicarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, 5-methylisophthalic acid, 5-tert-butylisophthalic acid, 5-aminoisophthalic acid, 5-hydroxyisophthalic acid, 2,5-dimethylterephthalic acid, tetramethylterephthalic acid, 1,4-naphthalene dicarboxylic acid, 2,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, 1,4-anthracene dicarboxylic acid, 1,4-anthraquinone dicarboxylic acid, 2,5-biphenyl dicarboxylic acid, 4,4'-biphenyl dicarboxylic acid, 1,5-diphenyl dicarboxylic acid, 4,4"-terphenyl dicarboxylic acid, 4,4'-diphenyl methane dicarboxylic acid, 4,4'-diphenyl ethane dicarboxylic acid, 4,4'-diphenyl propane dicarboxylic acid, and 4,4'-diphenyl hexafluoropropane dicarboxylic acid. dicarboxylic acids such as 4,4'-diphenyl ether dicarboxylic acid, 4,4'-bibenzyl dicarboxylic acid, 4,4'-stilbene dicarboxylic acid, 4,4'-ethynyl dibenzoic acid, 4,4'-carbonyl dibenzoic acid, 4,4'-sulfonyl dibenzoic acid, 4,4'-dithiodibenzoic acid, p-phenylenedicarboxylic acid, 3,3'-p-phenylenedicarboxylic acid, 4-carboxycinnamic acid, p-phenylenedicarboxylic acid, 3,3'-[4,4'-(methylenedi-p-phenylene)]dipropionic acid, 4,4'-[4,4'-(oxydi-p-phenylene)]dipropionic acid, 4,4'-[4,4'-(oxydi-p-phenylene)]dibutyric acid, (isopropylenedi-p-phenylenedioxy)dibutyric acid, and bis(p-carboxyphenyl)dimethylsilane.

Examples of heterocyclic dicarboxylic acids 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-thiadiazole-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 above-mentioned various dicarboxylic acids may also be acylated dihalides or anhydride structures. If the dicarboxylic acids are dicarboxylic acids that can give a linear structure to a polyamide, they are more ideal in maintaining the orientation of the liquid crystal molecules. Among them, terephthalic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 4,4'-diphenylethanedicarboxylic acid, 4,4'-diphenylpropanedicarboxylic acid, 4,4'-diphenylhexafluoropropanedicarboxylic acid, 2,2-bis(phenyl)propanedicarboxylic acid, 4,4-terphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,5-pyridinedicarboxylic acid or acylated dihalides thereof are more ideal. These compounds may also have isomers, and may also be a mixture including them. Furthermore, two or more compounds may be used in combination. Furthermore, the dicarboxylic acids used in the present invention are not limited to the above-exemplified compounds.

When a diamine as a raw material (also described as "diamine component") and a component selected from tetracarboxylic dianhydride (also described as "tetracarboxylic dianhydride component"), tetracarboxylic diester, diisocyanate and dicarboxylic acid as a raw material are reacted to obtain polyamine, polyamine ester, polyurea and polyamide, a known synthesis method can be used. Generally, there is a method of reacting a diamine component with one or more components selected from tetracarboxylic dianhydride component, tetracarboxylic diester, diisocyanate and dicarboxylic acid in an organic solvent.

The reaction between the diamine component and the tetracarboxylic dianhydride component is relatively easy to proceed in an organic solvent and does not generate by-products, which is advantageous from this point of view.

The organic solvent used in the above reaction is not particularly limited as long as it can dissolve the generated polymer. Furthermore, even if the organic solvent does not dissolve the polymer, it can be mixed with the above solvent to the extent that the generated polymer does not precipitate. In addition, the water in the organic solvent will hinder the polymerization reaction and further cause the generated polymer to hydrolyze, so it is better to use the organic solvent after dehydration.

Organic solvents, such as: N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, N-methylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 3-methoxy-N,N-dimethylpropaneamide, N-methylcaprolactam, dimethyl sulfoxide, tetramethyl urea, pyridine, dimethyl sulfoxide, hexamethyl sulfoxide, γ-butyrolactone, isopropyl alcohol, methoxymethylpentanol, dipentene, ethyl Amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellulose, ethyl cellulose, methyl cellulose acetate, butyl cellulose acetate, ethyl cellulose acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate , diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyl ester, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane, n-hexane, n-pentyl alkane, n-octane, diethyl ether, cyclohexanone, ethyl carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diethylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, 2-ethyl-1-hexanol, etc. These organic solvents may be used alone or in combination.

When the diamine component and the tetracarboxylic dianhydride component are reacted in an organic solvent, the following methods can be listed: a method of directly adding the tetracarboxylic dianhydride component to a solution obtained by dispersing or dissolving the diamine component in an organic solvent, or a method of adding the tetracarboxylic dianhydride component after dispersing or dissolving the diamine component in an organic solvent, a method of adding the diamine component to a solution obtained by dispersing or dissolving the tetracarboxylic dianhydride component in an organic solvent, or a method of alternately adding the tetracarboxylic dianhydride component and the diamine component, and any of these methods can be used. In addition, when the diamine component or the tetracarboxylic dianhydride component is composed of a plurality of compounds, they can be reacted in a premixed state, or they can be reacted separately in sequence, or low molecular weight bodies that have been reacted separately can be mixed and reacted to produce a high molecular weight body.

The temperature at which the diamine component and the tetracarboxylic dianhydride component react can be selected at any temperature, for example, -20 to 100°C, preferably -5 to 80°C. The reaction can be carried out at any concentration, for example, the total amount of the diamine component and the tetracarboxylic dianhydride component relative to the reaction solution is 1 to 50% by mass, preferably 5 to 30% by mass.

In the above polymerization reaction, the ratio of the total molar number of the tetracarboxylic dianhydride component to the total molar number of the diamine component can be selected at any value according to the molecular weight of the polyamide to be obtained. As in the usual polycondensation reaction, the closer this molar ratio is to 1.0, the greater the molecular weight of the generated polyamide. The ideal range is 0.8~1.2.

The method for synthesizing the polymer used in the present invention is not limited to the above method. When synthesizing polyamide, the tetracarboxylic acid dianhydride can be replaced with a tetracarboxylic acid derivative such as a tetracarboxylic acid dihalide of a corresponding structure, and the tetracarboxylic acid derivative can be reacted by a known method to obtain the corresponding polyamide. In addition, when synthesizing polyurea, diamine can be reacted with diisocyanate. When manufacturing polyamide ester or polyamide, diamine and a component selected from tetracarboxylic acid diester and dicarboxylic acid can be reacted in the presence of a known condensing agent, or after being derived into an acylate by a known method, it can be reacted with diamine.

The following methods can be cited as methods for making polyimide by imidization of the above-mentioned polyamic acid: thermal imidization by directly heating the solution of polyamic acid, and catalytic imidization by adding a catalyst to the solution of polyamic acid. In addition, the imidization rate of polyamic acid to polyimide is preferably 30% or more, and 30-99% is more preferred, from the viewpoint of making the voltage retention rate high. On the other hand, from the viewpoint of whitening characteristics, that is, inhibiting the precipitation of polymers in the varnish, it is preferably 70% or less. If both characteristics are considered, 40-80% is more ideal.

The temperature for thermal imidization of polyamine in solution is usually 100-400°C, preferably 120-250°C, and it is preferred to discharge the water generated by the imidization reaction to the outside of the system.

The catalytic imidization of polyamide can be carried out by adding an alkaline catalyst and an acid anhydride to a solution of polyamide, usually at -20 to 250°C, preferably at 0 to 180°C, and stirring. The amount of the alkaline catalyst is usually 0.5 to 30 mole times of the amide group, preferably 2 to 20 mole times, and the amount of the acid anhydride is usually 1 to 50 mole times of the amide group, preferably 3 to 30 mole times. Examples of the alkaline catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine, etc., among which pyridine is more ideal because it has a moderate alkalinity for the reaction to proceed. Examples of acid anhydrides include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, etc. Among them, acetic anhydride is more ideal because it is easy to purify after the reaction. The imidization rate obtained by catalytic imidization can be controlled by adjusting the amount of catalyst, reaction temperature, reaction time, etc.

When recovering the polymer generated from the reaction solution of the polymer, the reaction solution can be put into a poor solvent and precipitated. The poor solvent used for precipitation generation can be methanol, acetone, hexane, butyl cellulose, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, water, etc. The polymer put into the poor solvent and precipitated can be filtered and recovered, and then dried at room temperature or heated under normal pressure or reduced pressure. In addition, if the polymer recovered by precipitation is dissolved in an organic solvent again, and reprecipitated and recovered, and this operation is repeated 2 to 10 times, the impurities in the polymer can be reduced. The poor solvents at this time are, for example, alcohols, ketones, hydrocarbons, etc. If more than 3 selected poor solvents are used, the efficiency of purification will be better, so it is more ideal.

Furthermore, when the free radical generating film is composed of a polymer containing an organic group that induces free radical polymerization, the free radical generating film forming composition used in the present invention may also contain other polymers besides the polymer containing an organic group that induces free radical polymerization. In this case, the content of the other polymer in the total polymer components is preferably 5 to 95% by mass, and more preferably 30 to 70% by mass.

The molecular weight of the polymer contained in the free radical film forming composition is preferably 5,000 to 1,000,000, more preferably 10,000 to 150,000, when considering the strength of the free radical film obtained by coating the free radical film, the workability during film formation, the uniformity of the film, etc., as measured by GPC (Gel Permeation Chromatography) method.

When the free radical generating film used in the present invention is obtained by coating and curing a composition of a compound having a radical generating group and a polymer to form a film and fix it in the film, the polymer is a polyimide precursor produced according to the above-mentioned production method, and a polymer selected from the group consisting of polyimide, polyurea, polyamide, polyacrylate, polymethacrylate, etc., and at least one polymer can be obtained by using a diamine having a site for generating free radical polymerization as a diamine component accounting for 0 mol% of the total diamine components used in the synthesis of the polymer contained in the free radical generating film forming composition. The compound having a radical generating group added at this time can be listed as follows.

Compounds that generate free radicals by heat are compounds that generate free radicals by heating to a temperature above the decomposition temperature. Such free radical thermal polymerization initiators include, for example, ketone peroxides (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), diacyl peroxides (acetyl peroxide, benzoyl peroxide, etc.), hydrogen peroxides (hydrogen peroxide, tert-butyl hydroperoxide, isopropylbenzene hydroperoxide, etc.), dialkyl peroxides (di-tert-butyl peroxide, diisopropylbenzene peroxide, dilauryl peroxide, etc.) ), peroxyketal (dibutyl peroxide cyclohexane, etc.), alkyl perester (tert-butyl peroxyneodecanoate, tert-butyl peroxytrimethylacetate, tert-amyl peroxy 2-ethylcyclohexane, etc.), persulfate (potassium persulfate, sodium persulfate, ammonium persulfate, etc.), azo compounds (azobisisobutyronitrile, and 2,2'-bis(2-hydroxyethyl)azobisisobutyronitrile, etc.). Such free radical thermal polymerization initiators can be used alone or in combination of two or more.

The compound that generates free radicals by light is not particularly limited as long as it is a compound that starts free radical polymerization by light. Examples of such free radical photopolymerization initiators include benzophenone, Michler's ketone, 4,4'-bis(diethylamino)benzophenone, xanthone, thioxanthone, isopropylxanthone, 2,4-diethylthioxanthone, 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methyl-4'-isopropylpropiophenone, 1-hydroxycyclohexylphenone, isopropylphenyl ether, isobutylphenyl ether, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, camphorquinone, benzanthrone, 2-methyl-1-[4-(methylthio)phenyl]-2- Linopropan-1-one, 2-benzyl-2-dimethylamino-1-(4- 4-Dimethylaminobenzoic acid ethyl ester, 4-Dimethylaminobenzoic acid isopentyl ester, 4,4'-di(tert-butylperoxycarbonyl)benzophenone, 3,4,4'-tri(tert-butylperoxycarbonyl)benzophenone, 2,4,6-trimethylbenzyldiphenylphosphine oxide, 2-(4'-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triphenylphosphine oxide, , 2-(3',4'-dimethoxyphenylvinyl)-4,6-bis(trichloromethyl)-s-tri , 2-(2',4'-dimethoxyphenylvinyl)-4,6-bis(trichloromethyl)-s-tri , 2-(2'-methoxyphenylvinyl)-4,6-bis(trichloromethyl)-s-tri , 2-(4'-pentyloxyphenylvinyl)-4,6-bis(trichloromethyl)-s-tri , 4-[p-N,N-bis(ethoxycarbonylmethyl)]-2,6-bis(trichloromethyl)-s-tri , 1,3-bis(trichloromethyl)-5-(2'-chlorophenyl)-s-tri , 1,3-bis(trichloromethyl)-5-(4'-methoxyphenyl)-s-tri , 2-(p-dimethylaminophenylvinyl)benzoxazole, 2-(p-dimethylaminophenylvinyl)benzothiazole, 2-benzenebenzothiazole, 3,3'-carbonylbis(7-diethylaminocoumarin), 2-(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2'-biimidazole, 2,2'- Bis(2,4-dichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4,6-trichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 3-(2-methyl-2-dimethylaminopropionyl)carbazole, 3,6-bis(2-methyl-2- 1-Hydroxycyclohexylphenyl ketone, bis(5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tert-hexylperoxycarbonyl)benzophenone, 3,3'-bis(methoxycarbonyl)-4,4'-di(tert-butylperoxycarbonyl)benzophenone, 1-(2-phenyl)-1-nitro-2-nitro-1-butyl-2-nitro-2-acetyl)-1-nitro-2-acetyl)-2-nitro-1-nitro-2-acetyl)-1-nitro-2-acetyl)-2-nitro-1-nitro-2-acetyl)-2-nitro-2-acetyl) ...

Furthermore, even when the radical generating film is composed of a polymer having an organic group that induces radical polymerization, it may contain a compound having a group that generates radicals in order to promote radical polymerization when energy is given.

The free radical film-forming composition may contain an organic solvent that dissolves or disperses the polymer component and, if necessary, other components than the free radical generator. Such an organic solvent is not particularly limited, and for example, the organic solvent exemplified in the synthesis of the above-mentioned polyamide. Among them, N-methyl-2-pyrrolidone, γ-butyrolactone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 3-methoxy-N,N-dimethylpropaneamide, etc. are ideal from the viewpoint of solubility. In particular, N-methyl-2-pyrrolidone or N-ethyl-2-pyrrolidone is preferred, but a mixed solvent of two or more may also be used.

Furthermore, it is more preferable to mix a solvent which improves the uniformity and smoothness of the coating film with an organic solvent in which the components of the radical generating film forming composition have high solubility and use the mixture.

Solvents that improve the uniformity and smoothness of the coating, such as isopropyl alcohol, methoxymethylpentanol, methyl cellulose, ethyl cellulose, butyl cellulose, methyl cellulose acetate, butyl cellulose acetate, ethyl cellulose acetate, butyl carbitol, ethyl carbitol, ethyl carbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl Ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, di ...ethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate Isobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol acetate monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, 3- Butyl methoxypropionate, 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, etc. These solvents can also be mixed. When using these solvents, it is preferably 5-80% by mass of the total solvent contained in the liquid crystal alignment agent, and more preferably 20-60% by mass.

The radical film forming composition may contain components other than those mentioned above. Examples thereof include compounds that improve the uniformity of film thickness and surface smoothness when the radical film forming composition is applied, compounds that improve the adhesion between the radical film forming composition and the substrate, and compounds that improve the film strength of the radical film forming composition.

As compounds for improving the uniformity of film thickness and surface smoothness, there can be listed fluorine-based surfactants, silicone-based surfactants, non-ionic surfactants, etc. More specifically, for example: EFTOP EF301, EF303, EF352 (produced by Tohkem Products Co., Ltd.), Megafac F171, F173, R-30 (produced by Dainippon Ink Co., Ltd.), Fluorad FC430, FC431 (produced by Sumitomo 3M Co., Ltd.), AsahiGuard AG710, surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (produced by Asahi Glass Co., Ltd.), etc. When the surfactant is used, the usage ratio is preferably 0.01-2 parts by mass, more preferably 0.01-1 parts by mass, relative to 100 parts by mass of the total amount of the polymer contained in the free radical generating film forming composition.

Specific examples of compounds that improve the adhesion between the radical generating film-forming composition and the substrate include compounds containing functional silanes and compounds containing epoxy groups. For example: 3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 2-aminopropyl trimethoxysilane, 2-aminopropyl triethoxysilane, N-(2-aminoethyl)-3-aminopropyl trimethoxysilane, N-(2-aminoethyl)-3-aminopropyl methyl dimethoxysilane, 3-ureidopropyl trimethoxysilane, 3-ureidopropyl triethoxysilane, N-ethoxycarbonyl-3-aminopropyl trimethoxysilane, N-ethoxycarbonyl-3-aminopropyl trimethoxysilane, Propyl triethoxysilane, N-triethoxysilylpropyl triethylenetriamine, N-trimethoxysilylpropyl triethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazononyl acetate, 9-triethoxysilyl-3,6-diazononyl acetate, N-benzyl-3-aminopropyl trimethoxysilane, N-benzyl-3-aminopropyl triethoxysilane, N-phenyl-3-aminopropyl trimethoxysilane, N-phenyl-3-aminopropyl triethoxysilane, N-bis(oxyethyl)-3-aminopropyl trimethoxysilane, N-bis(oxyethyl)-3-aminopropyl triethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2 ,2-Dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N,N,N’,N’-tetraglycidyl-m-xylene diamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N’,N’-tetraglycidyl-4,4’-diaminodiphenylmethane, 3-(N-allyl-N-glycidyl)aminopropyltrimethoxysilane, 3-(N,N-diglycidyl)aminopropyltrimethoxysilane, etc.

In order to further enhance the strength of the free radical film, phenol compounds such as 2,2'-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane and tetrakis(methoxymethyl)bisphenol may be added. When such compounds are used, the amount is preferably 0.1 to 30 parts by weight, more preferably 1 to 20 parts by weight, based on 100 parts by weight of the total amount of the polymer contained in the free radical film forming composition.

Furthermore, in addition to the above, the radical generating film forming composition may also contain a dielectric or conductive substance for changing the electrical properties such as the dielectric constant and conductivity of the radical generating film within a range that does not impair the effects of the present invention.

[Free radical generating film] The free radical generating film of the present invention can be obtained using the above-mentioned free radical generating film forming composition. For example, the free radical generating film forming composition used in the present invention can be applied to a substrate, dried, and calcined to obtain a cured film, which can be directly used as a free radical generating film. In addition, the cured film can be rubbed, polarized, or irradiated with light of a specific wavelength, or treated with ion beams, or UV can be irradiated on a liquid crystal display element filled with liquid crystal as an alignment film for PSA.

The substrate on which the radical generating film-forming composition is applied is not particularly limited as long as it is a substrate with high transparency, and preferably a substrate on which a transparent electrode for driving liquid crystal is formed. Specific examples include substrates on which a transparent electrode is formed on plastic plates such as glass plates, polycarbonate, poly(meth)acrylate, polyether sulfone, polyarylate, polyurethane, polysulfone, polyether, polyether ketone, trimethylpentene, polyolefin, polyethylene terephthalate, (meth)acrylonitrile, triacetyl cellulose, diacetyl cellulose, cellulose acetate butyrate, etc.

The substrate that can be used for IPS-type liquid crystal display elements can also use electrode patterns such as standard IPS comb electrodes, PSA herringbone electrodes, and protrusion patterns such as MVA. In addition, in high-performance elements such as TFT-type elements, elements such as transistors are formed between the electrodes for driving liquid crystals and the substrate. When manufacturing a transmissive liquid crystal display element, the above-mentioned substrate is generally used, but when manufacturing a reflective liquid crystal display element, if it is a substrate with only one side, an opaque substrate such as a silicon wafer can also be used. At this time, the electrode formed on the substrate can also use a material such as aluminum that reflects light.

As a method for applying the radical generating film forming composition, spin coating, printing, ink jetting, inkjet coating, roll coating, etc. can be cited. However, from the aspect of productivity, transfer printing is widely used in industry and can also be preferably used in the present invention.

The drying step after coating the free radical generating film forming composition is not necessarily necessary, but when the time from coating to calcination of each substrate is not fixed, or when calcination is not performed immediately after coating, it is preferable to include a drying step. The drying step is not particularly limited as long as the solvent is removed to the extent that the coating shape is not deformed due to substrate transportation, etc. For example, the method of drying on a hot plate at a temperature of 40°C to 150°C, preferably 60°C to 100°C, for 0.5 to 30 minutes, preferably 1 to 5 minutes.

The coating formed by applying the free radical film-forming composition in the above method can be calcined to form a hardened film. The calcination temperature can usually be any temperature between 100°C and 350°C, preferably 140°C to 300°C, more preferably 150°C to 230°C, and more preferably 160°C to 220°C. The calcination time can usually be any time between 5 minutes and 240 minutes. It is preferably 10 to 90 minutes, and more preferably 20 to 90 minutes. Heating can be performed using commonly known methods, such as: hot plate, hot air circulation oven, IR oven, belt furnace, etc.

The thickness of the cured film can be selected as needed. It is preferably 5 nm or more, and more preferably 10 nm or more, because the reliability of the liquid crystal display element is easily obtained, which is ideal. In addition, the thickness of the cured film is preferably 300 nm or less, and more preferably 150 nm or less, because the power consumption of the liquid crystal display element will not become extremely large, which is ideal.

The first substrate with the free radical generating film can be obtained in the above manner, but the free radical generating film can be subjected to a uniaxial alignment treatment. The methods for the uniaxial alignment treatment include photo-alignment, oblique evaporation, friction, and uniaxial alignment treatment using a magnetic field.

When the orientation treatment is performed by rubbing in a single direction, for example, the substrate is moved in such a way that the rubbing cloth contacts the film while the rubbing roller wrapped with the rubbing cloth is rotated. In the case of the first substrate of the present invention on which the comb-tooth electrode has been formed, the direction is selected by utilizing the electrical properties of the liquid crystal. However, when using liquid crystal with positive dielectric anisotropy, the rubbing direction is preferably set to be substantially the same direction as the extension direction of the comb-tooth electrode.

As for the step of making the zero anchoring part and the strong anchoring part, a method of irradiating radiation with an arbitrary pattern through a mask or the like can be cited. This is a step of irradiating the free radical generating film with radiation in advance so that the free radical generating part disappears and does not become a zero anchoring state. The radiation when implementing this step can be polarized light or light of a specific wavelength, ion beam, etc. In particular, it is preferred to irradiate with light of a wavelength that makes the absorbance of the part of the photo free radical generating part the highest.

The second substrate of the present invention is the same as the first substrate except that it does not have a free radical generating film. It is preferably a substrate having a liquid crystal alignment film known in the past.

<Liquid crystal cell> The liquid crystal cell of the present invention is obtained by forming a free radical generating film on a substrate by the above method, arranging the substrate with the free radical generating film (first substrate) and the substrate with a known liquid crystal alignment film (second substrate) in a manner that the free radical generating film and the liquid crystal alignment film face each other, clamping a spacer and fixing it with a sealant, and injecting a liquid crystal composition containing liquid crystal and a free radical polymerizable compound to seal it. The size of the spacer used at this time is usually 1~30μm, preferably 2~10μm. The method of injecting the liquid crystal composition containing liquid crystal and free radical polymerizable compound is not particularly limited, and examples thereof include a vacuum method in which a mixture containing liquid crystal and polymerizable compound is injected after the prepared liquid crystal cell is placed in a reduced pressure state, and a dripping method in which a mixture containing liquid crystal and polymerizable compound is dripped and then sealed.

<Liquid crystal composition containing liquid crystal and free radical polymerizable compound> When the liquid crystal display element of the present invention is prepared, the polymerizable compound used together with the liquid crystal is not particularly limited as long as it is a free radical polymerizable compound, for example: a compound having one or more polymerizable unsaturated bonds in one molecule. Preferably, it is a compound having one polymerizable unsaturated bond in one molecule (hereinafter sometimes referred to as "a compound having a monofunctional polymerizable reactive group", "a compound having a monofunctional polymerizable reactive group", etc.). The polymerizable unsaturated bond is preferably a free radical polymerizable unsaturated bond, such as a vinyl bond.

At least one of the above-mentioned free radical polymerizable compounds is preferably a compound that is compatible with liquid crystal and has one polymerizable unsaturated bond in one molecule. In other words, a compound having a monofunctional free radical polymerizable group is preferred.

The polymerizable group of the free radical polymerizable compound is preferably a polymerizable group selected from the following structures. [Chemical 22] In the formula, * represents the bonding site with the compound molecule other than the polymerizable unsaturated bond. ^Rb represents a linear alkyl group having 2 to 8 carbon atoms, E represents a bonding group selected from 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.

Furthermore, the liquid crystal composition containing a liquid crystal and a radical polymerizable compound preferably contains a radical polymerizable compound whose Tg of a polymer obtained by polymerizing the radical polymerizable compound is 100° C. or less.

Compounds with monofunctional free radical polymerization reactive groups are those having unsaturated bonds capable of free radical polymerization in the presence of organic free radicals, such as methacrylate monomers such as tert-butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, lauryl methacrylate, and n-octyl methacrylate; acrylate monomers such as tert-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-tert-butoxystyrene, o-, m-, p-chloroform The present invention can be used to prepare a vinyl monomer such as vinyl styrene, 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-vinyl pyrrolidone, N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, etc.), (meth) acrylic acid derivatives (e.g., acrylonitrile, methacrylonitrile, acrylamide, isopropyl acrylamide, methacrylamide, etc.), halogenated vinyls (e.g., vinyl chloride, vinylidene chloride, tetrachloroethylene, hexachlorobutadiene, vinyl fluoride, etc.), but is not limited thereto. Such various free radical polymerizable monomers can be used alone or in combination of two or more. Moreover, they are preferably compatible with liquid crystals.

Furthermore, the radical polymerizable compound is preferably a compound represented by the following formula (1). In formula (1), ^Ra and ^Rb each independently represent a linear alkyl group having 2 to 8 carbon atoms, E represents a bonding group selected from a single bond, -O-, ^-NRc- , -S-, an ester bond, and an amide bond, and ^Rc represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

At least one of the aforementioned free radical polymerizable compounds is preferably a compound having one polymerizable unsaturated bond in one molecule that is compatible with liquid crystal, that is, preferably a compound having a monofunctional free radical polymerizable group.

Furthermore, in the case of the free radical polymerizable compound represented by the above formula (1), the one in which E is an ester bond (a bond represented by -C(=O)-O- or -OC(=O)-) is more ideal from the viewpoints of ease of synthesis, compatibility with liquid crystals, and polymerization reactivity. Specifically, the compound having the following structure is preferred, but there is no particular limitation. [Chemistry 24] In formula (1-1) and (1-2), Ra and Rb each independently represent a linear alkyl group having 2 to 8 carbon atoms.

Furthermore, the liquid crystal composition containing liquid crystal and a radical polymerizable compound preferably contains a radical polymerizable compound having a Tg of 100° C. or less when the radical polymerizable compound is polymerized.

The free radical polymerizable monomers may be used alone or in combination of two or more. They are preferably compatible with liquid crystal.

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

The polymer obtained by polymerizing the above-mentioned free radical polymerizable compound preferably has a Tg of 100° C. or less.

Liquid crystal generally refers to a substance that exhibits both solid and liquid properties. Representative liquid crystal phases include nematic liquid crystal and lamellar liquid crystal. The liquid crystal that can be used in the present invention is not particularly limited. For example, it is 4-pentyl-4'-cyanobiphenyl.

Then, sufficient energy is given to the liquid crystal cell into which the mixture containing the liquid crystal and the free radical polymerizable compound (liquid crystal composition) is introduced to cause the free radical polymerizable compound to undergo a polymerization reaction. This can be implemented, for example, by heating or irradiating UV, and the free radical polymerizable compound is polymerized in situ to exhibit the desired characteristics. Among them, the use of UV can make the orientation patternable and can perform the polymerization reaction in a short time. From this point of view, UV irradiation is preferred.

Furthermore, heating can be performed during UV irradiation. The heating temperature during UV irradiation is preferably within the temperature range where the introduced liquid crystal exhibits liquid crystal properties, usually above 40°C, and preferably below the temperature at which the liquid crystal changes to the isotropic phase.

Here, the wavelength of UV irradiation during UV irradiation is preferably selected to be the optimal wavelength of the reaction quantum yield of the polymerizable compound being reacted. The UV irradiation dose is usually 0.01~30 J, preferably below 10 J. The less the UV irradiation dose, the more it can suppress the reduction in reliability caused by the damage to the components constituting the liquid crystal display, and it is more ideal to improve the manufacturing tact by reducing the UV irradiation time.

When polymerization is performed by heating only without UV irradiation, it is preferably performed at a temperature within the range of a temperature at which the polymerizable compound reacts but below the decomposition temperature of the liquid crystal, for example, 100°C or more and 150°C or less.

When sufficient energy is given to allow the radical polymerizable compound to undergo polymerization reaction, a no-electric-field state in which no voltage is applied is preferred.

<Liquid crystal display element> The liquid crystal cell obtained in this way can be used to make a liquid crystal display element. For example: a reflective electrode, a transparent electrode, a λ/4 plate, a polarizing film, a color filter layer, etc. can be set on the liquid crystal cell according to the conventional method as needed to make a reflective liquid crystal display element. Also, a backlight, a polarizing plate, a λ/4 plate, a transparent electrode, a polarizing film, a color filter layer, etc. can be set on the liquid crystal cell according to the conventional method as needed to make a transmissive liquid crystal display element. [Example]

The present invention is further described with reference to the examples, but the present invention is not limited to the examples. The abbreviations of the compounds used in the polymerization of the polymer and the preparation of the film-forming composition, and the methods for evaluating the properties are as follows.

【Chemistry 25】

NMP: N-methyl-2-pyrrolidone, GBL: γ-butyl lactone, BCS: butyl celecoxib

<Viscosity measurement> For the polyamide solution, the viscosity at 25°C was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample volume of 1.1 mL and a Cone Rotor TE-1 (1°34’, R24).

<Determination of imidization rate> Put 20 mg of polyimide powder in an NMR sample tube (NMR standard sample tube φ5 manufactured by Kusano Scientific Co., Ltd.), add 0.53 ml of deuterated dimethyl sulfoxide (DMSO-d6, 0.05 mass% TMS (tetramethylsilane) mixture), and use ultrasound to completely dissolve it. The 500 MHz proton NMR of this solution is measured using a measuring device (JNW-ECA500 manufactured by JEC Data Corporation). The imidization rate is determined by using the proton from the structure that does not change before and after imidization as the reference proton, and the peak accumulation value of this proton and the peak accumulation value of the proton from the NH of the amide group appearing around 9.5~10.0 ppm are used to calculate it according to the following formula. Imidization rate (%) = (1-α・x/y) × 100 In the formula, x is the peak accumulation value of the protons from the NH of the amide group, y is the peak accumulation value of the reference proton, and α is the ratio of the number of reference protons to one NH proton of the amide group in polyamide (imidization rate is 0%).

<Polymerization and preparation of free radical film-forming composition> Synthesis Example 1 Polymerization of TC-1, TC-2(50)/DA-1(50), DA-2(50) polyimide In a 100ml 4-necked flask equipped with a nitrogen inlet tube, air cooling tube, and mechanical stirrer, weigh 1.62g of DA-1 (15.00mmol) and 3.96g of DA-2 (15.00mmol), add 48.2g of NMP, and stir in a nitrogen environment to completely dissolve. After confirming the dissolution, add 3.75g of TC-2 (15.00mmol) and react at 60℃ for 3 hours in a nitrogen environment. Return to room temperature, add 2.71g of TC-1 (13.80mmol), and react at 40℃ for 12 hours in a nitrogen environment. Confirm the polymerization viscosity, add TC-1 until the polymerization viscosity reaches 1000mPa・s, and obtain a polymerization solution with a polyamide concentration of 20 mass%. 60g of the polyamide solution obtained above was weighed into a 200ml Erlenmeyer flask equipped with a magnetic stirrer, and 111.4g of NMP was added to prepare a 7 mass% solution. While stirring, 9.10g (88.52mmol) of acetic anhydride and 3.76g (47.53mmol) of pyridine were added. After stirring at room temperature for 30 minutes, the mixture was stirred at 55°C for 3 hours to react. After the reaction was completed, the solution was returned to room temperature, and the reaction solution was injected into 500ml of methanol while stirring to precipitate solids. The solid was recovered by filtration, and then added to 300 ml of methanol and stirred for 30 minutes to wash. This was performed twice in total. The solid was recovered by filtration, air-dried, and then dried in a vacuum oven at 60° C. to obtain a polyimide (PI-1) having a number average molecular weight of 11,300, a weight average molecular weight of 32,900, and an imidization rate of 53%.

Synthesis Example 2 Polymerization of TC-1, TC-2 (50)/DA-1 (50), DA-3 (50) polyimide In a 100ml 4-necked flask equipped with a nitrogen inlet tube, an air cooling tube, and a mechanical stirrer, weigh 1.62g of DA-1 (15.00mmol) and 4.96g of DA-3 (15.00mmol), add 51.90g of NMP, and stir in a nitrogen environment to completely dissolve. After confirming the dissolution, add 3.75g of TC-2 (15.00mmol) and react at 60℃ for 3 hours in a nitrogen environment. Return to room temperature, add 2.64g of TC-1 (13.5mmol), and react at 40℃ for 12 hours in a nitrogen environment. Confirm the polymerization viscosity, add TC-1 until the polymerization viscosity reaches 1000mPa・s, and obtain a polymerization solution with a polyamide concentration of 20 mass%. 60g of the polyamide solution obtained above was weighed into a 200ml Erlenmeyer flask equipped with a magnetic stirrer, and 111.4g of NMP was added to prepare a 7 mass% solution. While stirring, 8.38g (81.4mmol) of acetic anhydride and 3.62g (45.8mmol) of pyridine were added. After stirring at room temperature for 30 minutes, the mixture was stirred at 55°C for 3 hours to react. After the reaction was completed, the solution was returned to room temperature, and the reaction solution was injected into 500ml of methanol while stirring to precipitate solids. The solid was recovered by filtration, and then washed by adding the solid into 300 ml of methanol and stirring for 30 minutes. This was performed twice in total. The solid was recovered by filtration, air-dried, and then dried in a vacuum oven at 60° C. to obtain a polyimide (PI-2) having a number average molecular weight of 13100, a weight average molecular weight of 34000, and an imidization rate of 55%.

Synthesis Example 3 Polymerization of TC-1, TC-2 (50)/DA-1 (50), DA-4 (50) polyimide In a 100ml 4-necked flask equipped with a nitrogen inlet tube, an air cooling tube, and a mechanical stirrer, weigh 1.62g of DA-1 (15.00mmol) and 5.65g of DA-4 (15.00mmol), add 55.4g of NMP, and stir in a nitrogen environment to completely dissolve. After confirming the dissolution, add 3.75g of TC-2 (15.00mmol) and react at 60℃ for 3 hours in a nitrogen environment. Return to room temperature, add 2.82g of TC-1 (14.40mmol), and react at 40℃ for 12 hours in a nitrogen environment. Confirm the polymerization viscosity, add TC-1 until the polymerization viscosity reaches 1000mPa・s, and obtain a polymerization solution with a polyamide concentration of 20 mass%. 60g of the polyamide solution obtained above was weighed into a 200ml Erlenmeyer flask equipped with a magnetic stirrer, and 111.4g of NMP was added to prepare a 7 mass% solution. While stirring, 8.36g (81.2mmol) of acetic anhydride and 3.65g (46.1mmol) of pyridine were added. After stirring at room temperature for 30 minutes, the mixture was stirred at 55°C for 3 hours to react. After the reaction was completed, the solution was returned to room temperature, and the reaction solution was injected into 500ml of methanol while stirring to precipitate the solid. The solid was recovered by filtration, and then added to 300 ml of methanol and stirred for 30 minutes to wash. This was performed twice in total. The solid was recovered by filtration, air-dried, and then dried in a vacuum oven at 60° C. to obtain a polyimide (PI-3) having a number average molecular weight of 12,900, a weight average molecular weight of 31,000, and an imidization rate of 51%.

Preparation of free radical film-forming composition: AL1 In a 50 ml Erlenmeyer flask equipped with a magnetic stirrer, 2.0 g of the polyimide powder (PI-1) obtained in Synthesis Example 1 was weighed, 18.0 g of NMP was added, and the mixture was stirred at 50°C to completely dissolve. Then 6.7 g of NMP and 6.7 g of BCS were added, and the mixture was further stirred for 3 hours to obtain the free radical film-forming composition: AL1 of the present invention (solid content: 6.0% by mass, NMP: 66% by mass, BCS: 30% by mass).

Preparation of free radical film-forming composition: AL2 In a 50 ml Erlenmeyer flask equipped with a magnetic stirrer, 2.0 g of the polyimide powder (PI-2) obtained in Synthesis Example 2 was weighed, 18.0 g of NMP was added, and the mixture was stirred at 50°C to completely dissolve. Then 6.7 g of NMP and 6.7 g of BCS were added, and the mixture was further stirred for 3 hours to obtain the free radical film-forming composition: AL2 of the present invention (solid content: 6.0% by mass, NMP: 66% by mass, BCS: 30% by mass).

Preparation of non-radical film-forming composition: AL3 In a 50 ml Erlenmeyer flask equipped with a magnetic stirrer, 2.0 g of the polyimide powder (PI-3) obtained in Synthesis Example 3 was weighed, 18.0 g of NMP was added, and the mixture was stirred at 50°C to completely dissolve. Then 6.7 g of NMP and 6.7 g of BCS were added, and the mixture was further stirred for 3 hours to obtain a free radical film-forming composition: AL3 (solid content: 6.0% by mass, NMP: 66% by mass, BCS: 30% by mass) as a comparative object.

【Table 1】 Table 1 Composition of polyimide

【Table 2】 Table 2 Composition of membrane-forming composition

【table 3】

<Production of polymerizable compounds> Example 1 of polymerizable compound synthesis: Synthesis of ethyl 2-(heptyloxymethyl)acrylate [Chemical 26]

Step 1: Synthesis of 2-hydroxyethyl methacrylate In a 500ml four-necked flask equipped with a nitrogen inlet tube, weigh 10mg of 4-methoxyphenol and 21.88g (195.1mmol) of DABCO (1,4-diazobicyclo[2.2.2]octane), add 50ml of pure water, add 11.52g (390.1mmol) of trioxymethylene under nitrogen atmosphere at below 10℃, and stir for 1 hour. After confirming that the slurry state has changed to a solution state, add 300ml of acetonitrile, add 19.53g (195.1mmol) of ethyl acrylate dropwise, and react at 50℃ for 5 hours. After the reaction is completed, transfer the reaction solution to a separatory funnel and add 50ml of n-hexane. Confirm that it has been separated into 3 layers, recover the lower 2 layers, and repeat this operation 3 times. Add hydrochloric acid until the pH becomes 4~5, and use ethyl acetate to extract. Add anhydrous magnesium sulfate to the extracted solution, stir and dry it, then filter and concentrate to obtain 22.9g (175.6mmol, yield 90%) of colorless and transparent oily liquid. The structure was confirmed to be the target substance by nuclear magnetic resonance spectroscopy ( ^1H -NMR spectrum). The measurement data are shown below. ^1H NMR (400 MHz, _CDCl3 ) δ: 6.81 (1H), 5.80 (1H), 4.31 (2H), 4.17 (1H), 1.98 (1H), 0.93 (3H)

Step 2: Synthesis of ethyl 2-(heptyloxymethyl)acrylate In a 500 ml 4-necked flask equipped with a nitrogen inlet tube, 19.9 g (152.9 mmol) of 2-hydroxymethacrylic acid obtained by the above method was measured, 300 ml of THF and 23.2 g (229.3 mmol) of triethylamine were added, and 25.0 g (168.2 mmol) of heptyl chloride was added dropwise in a nitrogen environment maintained at below 10°C, and the reaction was carried out for 6 hours. After the reaction, the precipitated triethylamine hydrochloride was removed by filtration, and the reaction solution was concentrated and redissolved in 300 ml of ethyl acetate, and washed 3 times with 100 ml of 10% potassium carbonate aqueous solution, washed 3 times with 50 ml of pure water, dried with anhydrous magnesium sulfate, filtered and concentrated to obtain a light yellow viscous substance. Then, it was purified by rapid column chromatography (developing solvent: ethyl acetate: n-hexane = 20:80), the solvent was removed, and vacuum drying was performed to obtain 32.2 g (133.0 mmol: yield 87%) of colorless and transparent oily liquid. The structure was confirmed by nuclear magnetic resonance spectroscopy ( ^1H -NMR spectrum). The measurement data are shown below. ¹ H NMR (400 MHz, CDCl ₃ )δ: 6.37 (1H), 5.80 (1H), 3.80 (2H), 4.23-4.21 (2H), 2.39-2.37 (2H), 1.64-1.58 (2H), 1.30-1.27 (9H), 0.86 (3H)

Synthesis Example 3 of Polymerizable Compounds Synthesis of Dihexyl Itaconate [Chemical 27]

In a 4-necked flask equipped with a Dean-Stark tube, 23.8 g (182.9 mmol) of itaconic acid and 35.5 g (347.5 mmol) of 1-hexanol were weighed, 500 ml of cyclohexane, 0.9 g (9.1 mmol) of concentrated sulfuric acid, and 0.04 g (1.82 mmol) of dibutylhydroxytoluene (BHT) were added, and a dehydration condensation reaction was carried out at 110°C for 24 hours in a nitrogen atmosphere. After the reaction, 100 ml of n-hexane was added to the reaction solution, and the solution was washed three times with 100 g of a 10% aqueous sodium carbonate solution, washed three times with 100 ml of pure water, and dried with anhydrous magnesium sulfate. After filtration, concentration and vacuum drying, 48.6 g (162.8 mmol: 89% yield) of a colorless, transparent oily liquid was obtained. The structure was confirmed to be the target compound by nuclear magnetic resonance spectroscopy ( ¹ H-NMR spectrum). The measurement data are as follows. ¹ H NMR (400 MHz, CDCl ₃ )δ: 6.30 (1H), 5.65 (1H), 4.20-4.00 (4H), 3.32 (2H), 1.64-1.58 (4H), 1.40-1.25 (12H), 0.96-0.83 (6H)

<Production of Liquid Crystal Display Element> Using the above-obtained AL1~AL3 and the liquid crystal alignment agent SE-6414 (manufactured by Nissan Chemical Industries, Ltd.) for horizontal alignment, a liquid crystal display element was produced according to the composition shown in Table 3.

(First substrate) The first substrate (hereinafter also referred to as IPS substrate) is an alkali-free glass substrate with a size of 30mm×35mm and a thickness of 0.7mm. An ITO (Indium-Tin-Oxide) electrode with a comb-shaped pattern with an electrode width of 10μm and an electrode spacing of 10μm is formed on the substrate, and pixels are formed. The size of each pixel is 10mm in length and about 5mm in width. After filtering AL1~AL3 and SE-6414 with a 1.0μm filter, they are applied to the electrode formation surface of the above IPS substrate by spin coating and dried on a hot plate at 80℃ for 1 minute. Then, AL1~AL3 were calcined at 220℃ for 20 minutes, and SE-6414 was calcined at 220℃ for 20 minutes to form a coating with a thickness of 100nm.

The coated substrate was shielded with a metal plate so that half of the substrate would not be exposed to light, and ultraviolet light was irradiated with a high-pressure mercury lamp through a bandpass filter with a wavelength of 313nm at an exposure amount of 5000mJ. This operation is hereinafter referred to as 1 UV treatment. After the exposure treatment, the rubbing direction was 5° inclined from the long side of the comb electrode. The rubbing treatment was performed using a spun yarn cloth: YA-20R manufactured by Yoshikawa Chemical Industry, with a roller diameter of 120mm, a rotation speed of 300rpm, a moving speed of 50mm/sec, and a pushing amount of 0.4mm. After the rubbing treatment, ultrasonic irradiation was performed in pure water for 1 minute and drying was performed at 80℃ for 10 minutes.

(Second substrate) The second substrate (also called the back ITO substrate) is an alkali-free glass substrate with a size of 30mm×35mm and a thickness of 0.7mm. An ITO film is formed on the back side (the surface facing the outside of the cell). In addition, a columnar spacer with a height of 4μm is formed on the surface (the surface facing the inside of the cell). SE-6414 was filtered with a 1.0μm filter and then applied to the glass surface of the back ITO substrate by spin coating. It was dried on a hot plate at 80℃ for 1 minute. Then, AL1 and AL2 were calcined at 220℃ for 20 minutes, and SE-6414 was calcined at 220℃ for 20 minutes. After obtaining a coating with a film thickness of 100nm each, a friction treatment was performed. The friction treatment was performed using a spun yarn cloth YA-20R manufactured by Yoshikawa Chemical Industry Co., Ltd., with a roller diameter of 120 mm, a rotation speed of 1000 rpm, a moving speed of 50 mm/sec, and a pushing amount of 0.4 mm. After the friction treatment, the samples were irradiated with ultrasound for 1 minute in pure water and dried at 80°C for 10 minutes.

(Production of liquid crystal cells) Using the above two substrates (first substrate and second substrate) with liquid crystal alignment films, leaving the liquid crystal injection port and sealing the surroundings, an empty cell with a cell gap of about 4μm is produced. At this time, the rubbing directions of the first substrate and the second substrate are respectively produced to be antiparallel and 85° crossed. In this empty cell, liquid crystal (Merck's IPS positive liquid crystal MLC-3019 and Merck's TN liquid crystal MLC3018U with various additives added under optimal conditions) is vacuum injected at room temperature, and the injection port is sealed to produce a liquid crystal cell. The obtained liquid crystal cell constitutes an IPS mode liquid crystal display element and a TN mode liquid crystal display element. The obtained liquid crystal cell is then heated at 120°C for 10 minutes. For the second UV treatment, a high-pressure mercury lamp was used through a bandpass filter with a wavelength of 313 nm. The liquid crystal cell was irradiated with ultraviolet light at an exposure dose of 5000 mJ. The details of the produced cell are shown in Table 4 below.

【Table 4】 ※SE-6414 is used for the back ITO side

<Visual evaluation of liquid crystal alignment> Using a polarizing plate mounted on a cross nicol, the alignment of the TN mode liquid crystal cell was confirmed. When UV treatment is not performed, the alignment constraint of the unilateral alignment film is lost (i.e., it becomes a zero anchoring state), and the constraint force of the chiral dopant in the liquid crystal cannot be fully twisted, so it becomes a horizontal alignment state. On the other hand, the area treated with UV loses the polymerization reactivity, so the anchoring force is maintained. Therefore, a twisted alignment occurs. As a result, two alignment states occur in the pixel. As shown in Figure 1, the area in the film that is exposed to UV is TN alignment (white), and the area that is not exposed to UV is horizontal alignment (black). The case is rated as 0, and the case where there is no change in each area is rated as ×.

【Table 5】 Table 5 Evaluation of alignment patterning characteristics

When using liquid crystal without additives and using materials that do not generate free radicals due to light, even if UV treatment is performed once, no alignment patterning, that is, no change in alignment constraint, occurs. It can be understood that the combination of the light free radical generating film and the additive of the present invention is important.

<Evaluation of electro-optical characteristics> Using cell 13~24 (horizontally aligned cell), the V-T curve was measured to implement the change of threshold voltage and the measurement of mode efficiency. The V-T curve was measured by installing a white LED backlight and a brightness meter in a way that the optical axis was aligned, and a liquid crystal cell (liquid crystal display element) with a polarizing plate installed was placed between them in a way that the brightness was minimized. The voltage was applied at 1V intervals up to 8V, and the brightness of the voltage was measured. The value of the driving threshold voltage was estimated from the obtained V-T curve. The mode efficiency was measured by calculating the ratio of the brightness of the liquid crystal cell at Vmax to the brightness of the LED transmitted light at the parallel Nicol of the polarizing plate. The anchoring measurement is performed by estimating the approximate value from the threshold voltage using the Fredericks shift method.

【Table 6】 Table 6

Cells 13 to 24 are horizontally aligned cells, so even if they become zero anchor alignment, there is no visual change. On the other hand, changes were observed in the threshold voltage and brightness of the V-T curve in the single UV exposure part and the unexposed part. This also shows that by implementing a single exposure, areas with different anchoring forces can be created within the pixel. [Industrial Applicability]

According to the present invention, different zero-plane regions can be industrially manufactured with good efficiency from low-cost raw materials. In addition, the liquid crystal display element obtained by the method of the present invention is useful as a liquid crystal display element of vertical alignment mode such as PSA type liquid crystal display, SC-PVA type liquid crystal display, etc.

Figure 1 shows a TN cell of a substrate having a film with zero-plane anchoring and non-zero-plane anchoring regions formed by having UV-irradiated regions and non-UV-irradiated regions. In the cell, the transparent regions are the regions that are not UV-irradiated and the opaque regions are the regions that are UV-irradiated.

Claims (20)

A method for manufacturing a patterned zero-surface anchor film includes the following steps: irradiating a free radical generating film with radiation in a specific area to form a patterned free radical generating film; and contacting a liquid crystal composition containing a liquid crystal and a free radical polymerizable compound with the patterned free radical generating film and, while maintaining this state, providing the liquid crystal composition with sufficient energy for the free radical polymerizable compound to undergo a polymerization reaction. The free radical generating film is formed by fixing an organic group that induces free radical polymerization. A method for manufacturing a patterned zero-surface anchor film includes the following steps: irradiating a free radical generating film with radiation in a specific area to form a patterned free radical generating film; and contacting a liquid crystal composition containing a liquid crystal and a free radical polymerizable compound with the patterned free radical generating film and, while maintaining this state, providing the liquid crystal composition with sufficient energy for the free radical polymerizable compound to undergo a polymerization reaction. The free radical generating film is obtained by coating and curing a composition of a compound having a free radical generating group and a polymer to form a film to fix the free radical generating compound in the film. A method for manufacturing a patterned zero-surface anchor film comprises the following steps: irradiating a free radical generating film with radiation in a specific area to form a patterned free radical generating film; and making a liquid crystal composition containing liquid crystal and a free radical polymerizable compound contact the patterned free radical generating film and while maintaining this state, giving the liquid crystal composition sufficient energy for the free radical polymerizable compound to undergo a polymerization reaction, wherein the free radical generating film is composed of a polymer containing an organic group that induces free radical polymerization. A method for manufacturing a patterned zero-surface anchoring film as claimed in any one of items 1 to 3 of the patent application, wherein the free radical generating film is a free radical generating film treated with uniaxial alignment. A method for manufacturing a patterned zero-surface anchoring film as claimed in any one of items 1 to 3 of the patent application, wherein the step of applying energy is performed in the absence of an electric field. As in the method for manufacturing a patterned zero-surface anchoring film of item 3 of the patent application, the polymer containing an organic group that induces free radical polymerization is at least one polymer selected from polyimide precursors, polyimide, polyurea and polyamide obtained by using a diamine component containing a diamine containing an organic group that induces free radical polymerization. A method for manufacturing a patterned zero-surface anchor film as claimed in any one of items 1, 3 and 6 of the patent application, wherein the organic group inducing free radical polymerization is an organic group represented by any one of the following structures [X-1] to [X-18], [W], [Y], and [Z];

In formulas [X-1] to [X-18], * represents a bonding site with a portion other than a polymerizable unsaturated bond of a compound molecule, S ₁ and S ₂ each independently represent -O-, -NR-, or -S-, R represents 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, and R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms;

In the formulas [W], [Y], and [Z], * represents a bonding site other than a polymerizable unsaturated bond with a compound molecule, Ar 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, ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and when ^R9 and ^R10 are alkyl groups, the terminals may also be bonded to each other to form a ring structure; Q represents the following structure; *─OR

In the formula, R ¹¹ represents -CH ₂ -, -NR-, -O-, or -S-, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, * represents a bonding site with a portion other than Q of the compound molecule; R ₁₂ represents 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. As in the method for producing a patterned zero-surface anchor film of claim 6, wherein the diamine containing an organic group inducing free radical polymerization is a diamine having a structure represented by the following general formula (6) or the following general formula (7);

In formula (6), R ⁶ represents a single bond, -CH ₂ -, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-; R ⁷ represents a single bond, or an unsubstituted or fluorine-substituted alkylene group having 1 to 20 carbon atoms; any one or more of -CH ₂ - or -CF ₂ - in the alkylene group may be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring; further, any one of the following groups, i.e., -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH- may be replaced by these groups provided that they are not adjacent to each other; R ⁸ represents a free radical polymerization reactive group selected from the following formulae;

In formulas [X-1] to [X-18], * represents a bonding site with a portion other than a radical polymerization-reactive group of a compound molecule, S ₁ and S ₂ each independently represent -O-, -NR-, or -S-, R represents 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, and R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms;

In formula (7), _T1 and _T2 are each independently a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH- _, -NH-, -CH2O-, -N(CH3)-, -CON( _CH3 )-, or -N( _{CH3 )} CO-; ^S0 represents a single bond, or an unsubstituted or fluorine-substituted alkylene group having 1 to 20 carbon atoms; any _-CH2- or _-CF2- of the alkylene group is - may be replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring. Furthermore, any of the following groups, i.e., -O-, -COO-, -OCO-, -NHCO-CONH-, or -NH-, may be replaced by these groups provided that they are not adjacent to each other. J is an organic group represented by any of the following formulae,

In the formulas [W], [Y], and [Z], * represents a bonding site with T ₂ , Ar 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, R ⁹ and R ¹⁰ each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and Q represents any of the following structures; *─OR

In the formula, R ¹¹ represents -CH ₂ -, -NR-, -O-, or -S-, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, * represents a bonding site with a portion other than Q of the compound molecule; R ₁₂ represents 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. A method for manufacturing a patterned zero-surface anchor film as claimed in any one of items 1 to 3 of the patent application, wherein at least one of the free radical polymerizable compounds is a compound having one polymerizable unsaturated bond in one molecule that is compatible with liquid crystal. As in the method for manufacturing a patterned zero-surface anchor film of claim 9, wherein the polymerization reactive group of the free radical polymerizable compound is selected from the following structures;

In the formula, * represents the bonding site with the compound molecule other than the polymerizable unsaturated bond; ^Rb represents a linear alkyl group having 2 to 8 carbon atoms; E represents a bonding group selected from a single bond, -O-, ^-NRc- , -S-, an ester bond and an amide bond; and ^Rc represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. A method for manufacturing a patterned zero-surface anchor film as claimed in any one of items 1 to 3 of the patent application, wherein the liquid crystal composition containing liquid crystal and a radical polymerizable compound contains a radical polymerizable compound whose Tg of a polymer obtained by polymerizing the radical polymerizable compound is below 100°C. A method for manufacturing a liquid crystal cell, using a patterned zero-surface anchoring film as described in any one of items 1 to 11 of the patent application, comprising the following steps: preparing a first substrate having a free radical generating film and a second substrate which may also have a free radical generating film; manufacturing a cell in such a way that the free radical generating film on the first substrate faces the second substrate; and filling a liquid crystal composition containing a liquid crystal and a free radical polymerizable compound between the first substrate and the second substrate. For example, the manufacturing method of the liquid crystal cell in item 12 of the patent application scope, wherein the second substrate is a second substrate without a free radical generating film. For example, the manufacturing method of the liquid crystal cell in item 13 of the patent application, wherein the second substrate is coated with a liquid crystal alignment film having uniaxial alignment. For example, the manufacturing method of the liquid crystal cell in item 14 of the patent application scope, wherein the liquid crystal alignment film with uniaxial alignment is a liquid crystal alignment film for horizontal alignment. A method for manufacturing a liquid crystal cell as claimed in any one of items 12 to 15 of the patent application, wherein the first substrate having a free radical generating film is a substrate having a comb-tooth electrode. A method for manufacturing a liquid crystal display element, using a film in a zero-surface anchoring state obtained by a method as described in any one of items 1 to 16 of the patent application scope. A liquid crystal display element is obtained using the manufacturing method of the liquid crystal display element as described in item 17 of the patent application scope. For example, in the liquid crystal display element of item 18 of the patent application, the first substrate or the second substrate has an electrode. If the liquid crystal display element in item 18 or 19 of the patent application scope is a low voltage driven lateral electric field liquid crystal display element.