TWI886191B - Method for manufacturing patterned liquid crystal display element - Google Patents

Abstract

The present invention provides a method for manufacturing a liquid crystal display element having two or three different alignment regions (in-plane (uniaxial) alignment region, out-of-plane alignment region, and tilted alignment region) in the same element in a simple and low-cost method. A method for manufacturing a liquid crystal display element comprises step (A): forming a free radical generating film on a substrate that can generate free radicals by light irradiation; and step (B): bringing a liquid crystal composition containing a liquid crystal and a free radical polymerizable compound into contact with the free radical generating film, and while maintaining the state, irradiating the liquid crystal composition with light having a peak at 240 to 400 nm that is sufficient to cause the free radical polymerizable compound to undergo a polymerization reaction; the free radical polymerizable compound has the function of aligning the liquid crystal vertically by polymerizing; and further comprises at least one of the following elements (Z1) and (Z2), and manufactures a liquid crystal display element in which at least two of the in-plane alignment region, the out-of-plane alignment region, and the tilted alignment region are patterned. Requirement (Z1): There is a step (C) between the aforementioned step (A) and the aforementioned step (B), which is to irradiate the aforementioned free radical generating film obtained in the aforementioned step (A) with light having a peak at 240 to 400 nm, thereby inactivating the free radical generating ability of the aforementioned free radical generating film. Requirement (Z2): The step of irradiating the aforementioned liquid crystal composition with light having a peak at 240 to 400 nm in the aforementioned step (B) is performed through a photomask.

Description

Method for manufacturing patterned liquid crystal display element

The present invention relates to a method for manufacturing a liquid crystal display element in which at least two of the in-plane alignment region, the out-of-plane alignment region, and the tilted alignment region are patterned by using a low-cost method that does not involve complicated steps.

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

In particular, products with touch panels such as tablet PCs, smart phones, and smart TVs prefer to use IPS mode, which does not easily disturb the display even when touched. In recent years, considering the perspective of improving 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, FFS has the following problems: Compared with IPS, the manufacturing cost of the substrate is high, and the display defects unique to the FFS mode, called Vcom offset, will occur. In addition, compared with the rubbing method, the photo-alignment has the advantages of increasing the size of the device that can be manufactured and greatly improving the display characteristics, but there are problems in the principle of photo-alignment (if it is a decomposition type, it is a display defect from the decomposition product, if it is an isomerization type, it is a burn-in caused by insufficient alignment force, etc.). In order to solve these problems, current LCD display device manufacturers and LCD alignment film manufacturers are making various efforts.

On the other hand, in recent years, an IPS mode using zero-plane anchoring (also called weak anchoring) has been proposed. It is reported that by using this method, the contrast can be improved and the driving voltage can be significantly lowered compared to the previous 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 other side of the substrate with an electrode that generates a transverse electric field to make it lose all liquid crystal alignment constraints, and the method uses these to make an IPS mode liquid crystal display element.

In recent years, some people have used thick polymer brushes to create a zero-surface state and proposed a technology for zero-surface anchoring the IPS mode (for example, refer to patent document 2). This technology can achieve a significant improvement in contrast ratio and a significant reduction in driving voltage.

On the other hand, there is the issue of response speed, especially when the voltage is OFF, which is significantly reduced. This is because the driving voltage becomes lower, and compared with the usual driving method, it responds with a weaker electric field, and because the anchoring force of the alignment film is extremely small, it takes time for the liquid crystal to recover.

As a solution to this problem, some people have proposed a method of providing zero anchoring only on the pixel electrode (for example, refer to Patent Document 3). It is reported that this method can take into account both the improvement of brightness and the response speed.

[Prior Art Literature]

[Patent Literature]

[Patent document 1] Japanese Patent No. 4053530

[Patent Document 2] Japanese Patent Publication No. 2013-231757

[Patent Document 3] Japanese Patent Publication No. 2017-211566

By using an alignment film that is appropriately designed for the application, the alignment state of various liquid crystals can be controlled. In particular, if an alignment film with anchoring force in the in-plane uniaxial direction is used, in-plane uniaxial alignment can be obtained, and if an alignment film with anchoring force in the out-of-plane direction is used, out-of-plane alignment can be obtained.

On the other hand, it is very difficult to make a liquid crystal element with both an in-plane uniaxial alignment region and an out-of-plane alignment region in the same element. This is because it is necessary to make regions with greatly different anchoring forces in the same element. In order to achieve this, it is necessary to change the anchoring force of any region after the liquid crystal element is made, or to pre-coat alignment films with different anchoring forces on the substrates constituting the element. There are still no reports on the former, and the latter has become a major issue in industrialization because it requires accurate coating in very small areas and preparation for alignment treatment technology.

If such technical issues are solved, liquid crystal elements with arbitrary orientation states can be formed in arbitrary areas, and can be expected to be applied to optical films, optical property modulation elements, etc.

The present invention is made to solve the above-mentioned problems and aims to provide a method for manufacturing a liquid crystal display element. By inducing a chemical reaction at the contact interface between the alignment film and the liquid crystal and inducing a chemical reaction in any region in the in-plane direction of the alignment film, the surface energy and anchoring energy of the interface reaction region are controlled to any state. A liquid crystal display element having two or three different alignment regions (in-plane (uniaxial) alignment region, out-of-plane alignment region, and tilted alignment region) in the same element is manufactured in a simple and low-cost method.

As a result of diligent research to solve the above-mentioned problems, the inventors of this case found that the above-mentioned problems can be solved, and completed the present invention having the following gist.

This invention includes the following aspects.

[1]

A method for manufacturing a liquid crystal display element, characterized by comprising: step (A): forming a free radical generating film on a substrate that can generate free radicals by irradiation with light; and step (B): bringing a liquid crystal composition containing a liquid crystal and a free radical polymerizable compound into contact with the free radical generating film, while maintaining the state, irradiating the liquid crystal composition with light having a peak at 240-400nm that is sufficient to cause the free radical polymerizable compound to undergo a polymerization reaction; the free radical polymerizable compound undergoes polymerization to have the effect of causing the free radical polymerizable compound to undergo a polymerization reaction; The invention relates to a method for manufacturing a liquid crystal display device having a function of vertically aligning the liquid crystal; and further comprising at least one of the following elements (Z1) and (Z2), and manufacturing a liquid crystal display device having at least two areas of the in-plane alignment area, the out-of-plane alignment area, and the tilted alignment area being patterned; element (Z1): there is a step (C) between the aforementioned step (A) and the aforementioned step (B), which is to irradiate the aforementioned free radical generating film obtained in the aforementioned step (A) with light having a peak at 240-400nm, thereby inactivating the free radical generating ability of the aforementioned free radical generating film. Element (Z2): the step of irradiating the aforementioned liquid crystal composition with light having a peak at 240-400nm in the aforementioned step (B) is performed through a light mask.

[2]

A method for manufacturing a liquid crystal display element as described in [1], wherein the free radical generating film is a film that has been subjected to uniaxial alignment treatment.

[3]

A method for manufacturing a liquid crystal display element as described in [1] or [2], wherein the step (B) of irradiating the liquid crystal composition with light having a peak at 240-400nm is performed in the absence of an electric field.

[4]

A method for manufacturing a liquid crystal display element as described in any one of [1] to [3], wherein the free radical generating film has a polymer containing an organic group that induces free radical polymerization.

[5]

A method for manufacturing a liquid crystal display element as described in [4], wherein the aforementioned polymer containing an organic group that induces free radical polymerization has a structural unit represented by the following formula (1) in the main chain.

In formula (1), A represents an organic group that induces free radical polymerization.

[6]

A method for manufacturing a liquid crystal display element as described in [4] or [5], wherein the polymer is selected from at least one of a polyimide precursor, polyimide, polyurea, and polyamide obtained by using a diamine component containing a diamine having an organic group that induces free radical polymerization.

[7]

A method for manufacturing a liquid crystal display element as described in [5], wherein the organic group inducing free radical polymerization is a group represented by the following formula (3).

[Chemistry 2]----R ⁶ ─R ⁷ ─R ⁸ (3)

In formula (3), the dotted line represents the bond to the benzene ring, 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 -CH ₂ - or -CF ₂ -One or more of them may be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic group. In addition, 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; ^R8 represents an organic group that induces free radical polymerization and is selected from the group represented by the formula [X-1] to [X-18], [W], [Y], and [Z];

In formulas [X-1] to [X-18], * represents a bonding site with ^R7 , _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; [Chemical 4]

In formulas [W], [Y], and [Z], * represents a bonding site with R ⁷ , S ³ represents a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH 3 )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-, 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 are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group, a benzyl group, or a phenethyl group, and when they are an alkyl group or an alkoxy group, R ⁹ and R ¹⁰ may form a ring; Q represents any of the following structures;

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 an atomic bond; 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.

[8]

A method for manufacturing a liquid crystal display element as described in [6], wherein the diamine containing an organic group that induces free radical polymerization is a diamine having a structure represented by the following formula (2).

[Chemistry 6]

In formula (2), ^A1 and ^A2 each independently represent a hydrogen atom or a group represented by the following formula (3), provided that at least one of ^A1 and ^A2 represents a group represented by the following formula ( ₃ ), E represents a single bond, -O-, -C(CH3) _2- , -NH-, -CO-, -NHCO-, -COO-, -( _CH2 ) _m- , _-SO2- , or a divalent organic group composed of any combination thereof, and m represents an integer of 1 to 8.

p represents an integer of 0 to 2. When p is 2, each of ^A2 and E independently has the above definition. When p is 0, ^A1 is composed of a group represented by the following formula (3).

[Chemistry 7]----R ⁶ ─R ⁷ ─R ⁸ (3)

In formula (3), the dotted line represents a bond to the benzene ring, 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 -CH ₂ - or -CF ₂ - one or more of them can also be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic group. In addition, they can also be replaced by any of the following groups, that is, -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH- provided that they are not adjacent to each other; R ⁸ represents an organic group that induces free radical polymerization and is selected from the formulas [X-1] to [X-18], [W], [Y] and [Z]; [Chemical 8]

In formulas [X-1] to [X-18], * represents a bonding site with R ⁷ , 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 formulas [W], [Y], and [Z], * represents a bonding site with R ⁷ , S ³ represents a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH 3 )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-, 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 are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group, a benzyl group, or a phenethyl group, and when they are an alkyl group or an alkoxy group, R ⁹ and R ¹⁰ may form a ring; Q represents any of the following structures;

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 an atomic bond; 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]

A method for manufacturing a liquid crystal display element as described in any one of [1] to [8], wherein at least one of the aforementioned free radical polymerizable compounds is a compound having one polymerizable unsaturated bond in one molecule and being compatible with liquid crystal.

[10]

A method for manufacturing a liquid crystal display element as described in [9], wherein the polymerization reactive group possessed by the aforementioned 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 an alkyl group having 3 to 20 carbon atoms, and 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, and the alkyl group of ^Rb represents a straight chain, branched, or cyclic alkyl group.

[11]

A method for manufacturing a liquid crystal display element as described in any one of [1] to [10], 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.

[12]

The manufacturing method of a liquid crystal display element as described in any one of [1] to [11] further comprises the following steps: preparing a first substrate having a free radical generating film and a second substrate, arranging the first substrate such 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 to manufacture a liquid crystal cell.

[13]

A method for manufacturing a liquid crystal display element as described in [12], wherein the second substrate has a free radical generating film.

[14]

A method for manufacturing a liquid crystal display element as described in [12], wherein the second substrate is a substrate coated with a liquid crystal alignment film having a uniaxial alignment property.

[15]

A method for manufacturing a liquid crystal display element as described in [14], wherein the liquid crystal alignment film having a uniaxial alignment property is a liquid crystal alignment film for horizontal alignment.

[16]

A method for manufacturing a liquid crystal display element as described in any one of [12] to [15], wherein the first substrate having a free radical generating film is a substrate having a comb-tooth electrode.

According to the present invention, a method for manufacturing a liquid crystal display element having two or three different alignment regions (in-plane (uniaxial) alignment region, out-of-plane alignment region, and tilted alignment region) in the same element can be provided in a simple and low-cost method.

1: Dark vision (black)

a: The middle color part of dark field (black) 1

b: The black part of dark field (black) 1

2: Bright field (white)

3: Middle color (gray)

4: Bright field of vision (white)

5: Bright field (white)

6: Bright field of vision (white)

7: Middle color (gray)

8: Dark Vision (Black)

9: Dark Vision (Black)

10: Bright field (white)

11: Middle color (gray)

101: Liquid crystal display element

102: Comb electrode substrate

102a: Base material

102b: Linear electrode

102c: Free radicals produce membranes

102d: Base material

102e: Surface electrode

102f: Insulation film

102g: Linear electrode

102h: Free radicals produce membrane

103: Liquid crystal composition

104: Opposite substrate

104a: Liquid crystal alignment film

104b: Base material

[Figure 1A] Figure 1A is a photograph of the liquid crystal display element obtained in Example 5.

[Figure 1B] Figure 1B is a schematic diagram showing a photograph of the liquid crystal display element of Figure 1A.

[Figure 2A] Figure 2A is a photograph of the liquid crystal display element obtained in Comparative Example 4.

[Figure 2B] Figure 2B is a schematic diagram showing a photograph of the liquid crystal display element of Figure 2A.

[Figure 3A] Figure 3A is a photograph of the liquid crystal display element obtained in Example 1.

[Figure 3B] Figure 3B is a schematic diagram showing a photograph of the liquid crystal display element of Figure 3A.

[Figure 4A] Figure 4A is a photograph of the liquid crystal display element obtained in Example 23.

[Figure 4B] Figure 4B is a schematic diagram showing a photograph of the liquid crystal display element of Figure 4A.

[Figure 5A] Figure 5A is a photograph of the liquid crystal display element obtained in Example 24.

[Figure 5B] Figure 5B is a schematic diagram showing a photograph of the liquid crystal display element of Figure 5A.

[Figure 6] Figure 6 is a photograph of the liquid crystal display element obtained in Example 25 and Example 26.

[Figure 7] Figure 7 is a photograph of the liquid crystal display element obtained in Example 27.

[Figure 8] Figure 8 is a photograph of the liquid crystal display element obtained in Example 30.

[Figure 9A] Figure 9A is a photograph of the liquid crystal display element obtained in Example 32.

[Figure 9B] Figure 9B is a schematic diagram showing a photograph of the liquid crystal display element of Figure 9A.

[Figure 10] is a schematic cross-sectional view showing an example of a liquid crystal display element of the present invention.

[Figure 11] is a schematic cross-sectional view showing another example of the liquid crystal display element of the present invention.

The following is a detailed description of the manufacturing method of the liquid crystal display element of the present invention, but the description of the constituent elements recorded below is an example of an implementation of the present invention and is not specific to the contents.

(Manufacturing method of liquid crystal display element)

The manufacturing method of the liquid crystal display element of the present invention includes the following step (A) and the following step (B).

Step (A): A step of forming a free radical generating film on a substrate that can generate free radicals by light irradiation.

Step (B): A step of bringing a liquid crystal composition containing a liquid crystal and a free radical polymerizable compound into contact with a free radical generating film, and while maintaining this state, irradiating the liquid crystal composition with light having a peak at 240-400nm that is sufficient to cause the free radical polymerizable compound to undergo a polymerization reaction.

The free radical polymerizable compound in the above step (B) is a compound that has the function of aligning liquid crystals vertically by polymerization.

In addition, the manufacturing method of the liquid crystal display element of the present invention includes at least one of the following requirements (Z1) and (Z2).

Requirement (Z1): There is a step (C) between step (A) and step (B), which is to irradiate the free radical generating film obtained in step (A) with light having a peak in the range of 240-400nm, thereby inactivating the free radical generating ability of the free radical generating film.

Requirement (Z2): The step (B) of irradiating the liquid crystal composition with light having a peak at 240-400nm is performed through a photomask.

The present invention, which includes the above-mentioned steps (A) and (B) and further satisfies at least one of the requirements (Z1) and (Z2), can manufacture a liquid crystal display element in which at least two regions of the in-plane alignment region, the out-of-plane alignment region, and the tilted alignment region are patterned.

<Free radical generation film>

In the present invention, a free radical film is formed on the substrate.

Here, the free radical generating membrane refers to a membrane that generates free radicals.

A free radical generating film, for example formed by a free radical generating film forming composition.

<Free radical generating film forming composition>

The components of the free radical-generating film-forming composition include a polymer and a group that generates free radicals. In this case, the free radical-generating film-forming composition may be a composition containing a polymer bonded with a group that generates free radicals, or a composition containing a compound having a group that generates free radicals and a polymer that serves as a base resin.

By coating such a free radical generating film forming composition on a substrate and curing the coated film, a free radical generating film in which the radical generating group is fixed in the film can be obtained. The radical generating group is preferably an organic group that induces free radical polymerization.

When the free radical generating film is composed of a polymer containing an organic group that induces free radical polymerization, the polymer containing an organic group that induces free radical polymerization can be, for example, a polymer having a structural unit represented by the following formula (1) in the main chain.

In formula (1), A represents an organic group that induces free radical polymerization.

When using a polymer containing an organic group that induces free radical polymerization, in order to obtain a polymer having a group that generates free radicals, it is preferable 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 site in the side chain that decomposes and generates free radicals due to light irradiation as a monomer component for production. On the other hand, monomers that generate free radicals have problems such as spontaneous polymerization, and there is a risk of becoming unstable compounds.

Therefore, considering the ease of synthesis, it is preferable to use a polymer derived from a diamine having a free radical generating site, and more preferably a polyimide precursor such as polyamic acid, polyamic acid ester, polyimide, polyurea, polyamide, etc.

The organic group that induces free radical polymerization includes, for example, the group represented by the following formula (3).

[Chemistry 13]----R ⁶ ─R ⁷ ─R ⁸ (3)

In formula (3), the dotted line represents a bond to the benzene ring, 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 -CH ₂ - or -CF ₂ - one or more of them may be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic group. In addition, 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; R ⁸ represents an organic group that induces free radical polymerization and is selected from the group represented by the formulas [X-1] to [X-18], [W], [Y], and [Z],

In formulas [X-1] to [X-18], * represents a bonding site with ^R7 , _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.

In the formulas [W], [Y], and [Z], * represents a bonding site with R ⁷ , S ³ represents a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH 3 )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-, 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 are each independently an alkyl group having 1 to ₁₀ carbon atoms, an alkoxy group, a benzyl group, or a phenethyl group, and when they are an alkyl group or an alkoxy group, R ⁹ and R ¹⁰ may form a ring, and Q represents any of the following structures,

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 an atomic bond, and 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.

Specifically, the organic groups selected from the above-mentioned formulas [W], [Y] and [Z] are preferably the following. In particular, from the perspective of the reliability of the obtained liquid crystal display element, (b) and (c) are more preferred.

An ideal embodiment of the polymer containing an organic group that induces free radical polymerization can include a diamine having an organic group that induces free radical polymerization.

Specifically, diamines containing such a free radical generating site include diamines having a side chain that can generate free radicals and polymerize, such as the diamine represented by the following formula (2). In addition, it is not limited to these.

In formula (2), ^A1 and ^A2 each independently represent a hydrogen atom or a group represented by formula (3), provided that at least one of ^A1 and ^A2 represents a group represented by formula (3), E represents a single bond, -O-, -C( _CH3 ) _2- , -NH-, -CO-, -NHCO-, -COO-, -( _CH2 ) _m- , _-SO2- , or a divalent organic group composed of any combination thereof, and m represents an integer of 1 to 8.

“Any combination thereof” includes, but is not limited to, —O-(CH ₂ ) _m -O-, —OC(CH ₃ ) ₂ -, —CO-(CH ₂ ) _m -, —NH-(CH ₂ ) _m -, —SO ₂ -(CH ₂ ) _m -, —CONH-(CH ₂ ) _m -, —CONH-(CH ₂ ) _m -NHCO-, and —COO-(CH ₂ ) _m -OCO-.

p represents an integer of 0 to 2. When p is 2, each of ^A2 and E independently has the above definition. When p is 0, ^A1 is composed of a group represented by the following formula (3).

In the above formula (2), the bonding positions of the two amino groups (-NH ₂ ) when p=0 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, the 2,4 positions, 2,5 positions, or 3,5 positions are preferred. Considering the ease of synthesizing diamine, the 2,4 positions or 3,5 positions are more preferred.

The diamine having a photoreactive group containing at least one selected from the group consisting of methacrylic acid group, acrylic acid group, vinyl group, allyl group, coumarin group, styryl group and cinnamyl group, specifically, the following compounds can be listed, but are not limited to them.

[Chemistry 19]

[Chemistry 20]

In the formula, ^J1 represents a single bond, -O-, -COO-, -NHCO-, or -NH-bonding group, and ^J2 represents a single bond, or an unsubstituted or fluorine-substituted alkylene group having 1 to 20 carbon atoms.

The diamine having an organic group represented by the formula selected from the above [W], [Y] and [Z] is preferably represented by the following formula from the viewpoints of ease of synthesis, versatility, properties, etc., but is not limited thereto.

[Chemistry 21]

In the formula, n is an integer of 2 to 8, E represents a single bond, -O-, -C(CH ₃ ) ₂ -, -NH-, -CO-, -NHCO-, -COO-, -(CH ₂ ) _m -, -SO ₂ -, -O-(CH ₂ ) _m -O-, -OC(CH ₃ ) ₂ -, -CO-(CH ₂ ) _m -, -NH-(CH ₂ ) _m -, -SO ₂ -(CH ₂ ) _m -, -CONH-(CH ₂ ) _m -, -CONH-(CH ₂ ) _m -NHCO- or -COO-(CH ₂ ) _m -OCO-, and m is an integer of 1 to 8.

[Chemistry 22]

In the formula, n is an integer between 2 and 8.

The above diamines can also be used alone or in combination of two or more, depending on the liquid crystal orientation when making a free radical generating film, the sensitivity in the polymerization reaction, the voltage holding characteristics, the stored charge and other characteristics.

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

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 the diamine component. Specifically, 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'-diaminobiphenyl, 3,3'-bis(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-aminophenyl)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'-diaminodiphenylamine, N-methyl(3 ,3'-diaminodiphenyl)amine, N-methyl(3,4'-diaminodiphenyl)amine, N-methyl(2,2'-diaminodiphenyl)amine, N-methyl(2,3'-diaminodiphenyl)amine, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 2,2'-diaminobenzophenone, 2,3'-diaminobenzophenone, 1,4-diaminonaphthalene, 1,5-diaminonaphthalene, 1,6-diamino Naphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 1,2-bis(4-aminophenyl)ethane, 1,2-bis(3-aminophenyl)ethane, 1,3-bis(4-aminophenyl)propane, 1,3-bis(3-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1,4-bis(3-aminophenyl)butane, bis(3,5-diethyl-4-aminophenyl) Methane, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(4-aminobenzyl)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4'-[1,4-phenylenebis(methylene)]diphenylamine, 4,4'-[1,3-phenylenebis(methylene)]diphenylamine, 3,4'-[1,4-phenylenebis(methylene)]diphenylamine methyl)] 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) ketone], 1,4-phenylenebis[(3-aminophenyl) ketone], 1,3-phenylenebis[(4-aminophenyl) ketone], 1,3-phenylenebis[(3-aminophenyl) Ketone], 1,4-phenylenebis(4-aminobenzoate), 1,4-phenylenebis(3-aminobenzoate), 1,3-phenylenebis(4-aminobenzoate), 1,3-phenylenebis(3-aminobenzoate), bis(4-aminophenyl)terephthalate, bis(3-aminophenyl)terephthalate, bis(4-aminophenyl)isophthalate, bis(3-aminophenyl)isophthalate, N,N'-(1,4-phenylene)bis( 4-aminobenzoamide), N,N’-(1,3-phenylene)bis(4-aminobenzoamide), N,N’-(1,4-phenylene)bis(3-aminobenzoamide), N,N’-(1,3-phenylene)bis(3-aminobenzoamide), N,N’-bis(4-aminophenyl)-p-phenylenediamine, N,N’-bis(3-aminophenyl)-p-phenylenediamine, N,N’-bis(4-aminophenyl)-m-phenylenediamine, N,N’-bis(3- 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-amino-4-methylphenyl)hexafluoropropane, ,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)octane, 1,8-bis(3 Aromatic diamines such as 1,9-bis(4-aminophenoxy)octane, 1,9-bis(4-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)dodecane ; Bis(4-aminocyclohexyl)methane, bis(4-amino-3-methylcyclohexyl)methane and other aliphatic cyclodiamines; 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 and other aliphatic diamines; 1,3-bis[2-( Diamines with urea structure such as [(4-aminophenyl)ethyl]urea, 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 (Boc represents tert-butoxycarbonyl) such as N-tert-butoxycarbonyl-N-(2-(4-aminophenyl)ethyl)-N-(4-aminobenzyl)amine, etc.

The above-mentioned other diamines can also be used alone or in combination of two or more, depending on the liquid crystal orientation when making a free radical generating film, the sensitivity in the polymerization reaction, the voltage holding characteristics, the stored charge and other characteristics.

In the synthesis of a polymer of polyamide, the tetracarboxylic dianhydride to be reacted with the diamine component is not particularly limited. Specifically, the following can be cited: pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7-anthracenetetracarboxylic acid, 1,2,5,6-anthracenetetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, 2,3,3',4'-biphenyltetracarboxylic acid, bis(3,4-dicarboxyphenyl)ether, 3,3',4,4'-benzophenonetetracarboxylic acid, bis(3,4-dicarboxyphenyl)sulfone, bis(3,4-dicarboxyphenyl)methane, 2,2-bis(3,4-dicarboxyphenyl)propane, 1,1,1,3,3,3-hexafluoro-2,2-bis(3,4-dicarboxyphenyl)propane , bis(3,4-dicarboxyphenyl)dimethylsilane, bis(3,4-dicarboxyphenyl)diphenylsilane, 2,3,4,5-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, oxydiphthalatetetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2-dimethyl-1,2,3,4-cyclo butanetetracarboxylic acid, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cycloheptanetetracarboxylic acid, 2,3,4,5-tetrahydrofurantetracarboxylic acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid, bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic acid, bicyclo[4.3.0]nonane-2,4,7,9-tetracarboxylic acid, bicyclo[4.4.0]decane-2,4,7,9-tetracarboxylic acid, bicyclo[4.4.0]decane-2,4,8,10-tetracarboxylic acid, tricyclo[6.3.0.0 <2,6>] undecane-3,5,9,11-tetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 4-(2,5-dioxotetrahydro furan-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<3,6>.0<2,7>] dodeca-4,5,9,10-tetracarboxylic acid, 3,5,6-tricarboxynorbornane-2:3,5:6 dicarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid and other tetracarboxylic acid dianhydrides.

Of course, tetracarboxylic dianhydride can also be used alone or in combination of two or more depending on the liquid crystal orientation when making a free radical generation film, the sensitivity in the polymerization reaction, the voltage holding characteristics, the stored charge and other characteristics.

When the polymer is a polyamic acid ester, the structure of the tetracarboxylic acid dialkyl ester that reacts with the above-mentioned diamine component is not particularly limited, and specific examples are listed below.

Specific examples of aliphatic tetracarboxylic acid diesters include: 1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2,3,4- Cyclopentanetetracarboxylic acid dialkyl esters, 2,3,4,5-tetrahydrofurantetracarboxylic acid dialkyl esters, 1,2,4,5-cyclohexanetetracarboxylic acid dialkyl esters, 3,4-dicarboxy-1-cyclohexylsuccinic acid dialkyl esters, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid dialkyl esters, 1,2,3,4-butanetetracarboxylic acid dialkyl esters, biscyclo[3.3.0]octane 2,4,6,8-tetracarboxylic acid dialkyl esters, 3,3',4,4'-dicyclohexyltetracarboxylic acid dialkyl esters, 2,3,5-tricarboxycyclopentylacetic acid dialkyl esters, cis-3,7-dibutylcycloocta-1,5-diene-1,2,5,6-tetracarboxylic acid dialkyl esters, 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-dihydroxytetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid dialkyl ester, etc.

Aromatic tetracarboxylic acid dialkyl esters include: pyromellitic acid dialkyl ester, 3,3',4,4'-biphenyl tetracarboxylic acid dialkyl ester, 2,2',3,3'-biphenyl tetracarboxylic acid dialkyl ester, 2,3,3',4-biphenyl tetracarboxylic acid dialkyl ester, 3,3',4,4'- benzophenone tetracarboxylic acid dialkyl ester, 2,3,3',4'-benzophenone tetracarboxylic acid dialkyl ester, bis(3,4-dicarboxyphenyl) ether dialkyl ester, bis(3,4-dicarboxyphenyl) sulfone dialkyl ester, 1,2,5,6-naphthalene tetracarboxylic acid dialkyl ester, 2,3,6,7-naphthalene tetracarboxylic acid dialkyl ester, etc.

In the synthesis of a polymer of polyurea, there is no particular limitation on the diisocyanate to be reacted with the above-mentioned diamine component, and it can be used according to availability, etc. The specific structure of the diisocyanate is shown below.

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

Although the aliphatic diisocyanates shown in K-1~K-5 have poor reactivity, they have the advantage of improving 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 reducing solvent solubility. Considering versatility and characteristics, K-1, K-7, K-8, K-9, and K-10 are suitable. Considering the viewpoint of electrical characteristics, K-12 is suitable. Considering the viewpoint of liquid crystal alignment, K-13 is suitable. More than one diisocyanate can be used in combination. It is suitable to use various diisocyanates according to the desired characteristics.

In addition, a portion of the diisocyanate can be replaced with the tetracarboxylic dianhydride described above, and can be used in the form of a copolymer of polyamide and polyurea, or can be used in the form of a copolymer of polyimide and polyurea by chemical imidization.

In the synthesis of a polymer that is a polyamide, the structure of the dicarboxylic acid to be reacted is not particularly limited, and specific examples 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.

The 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, Carboxylic acid, 1,3-cyclohexane dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid, 1,4-(2-norbornene) dicarboxylic acid, 5-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]octane dicarboxylic acid, 1,3-adamantanedicarboxylic acid, 4,8-dihydroxy-1,3-adamantanedicarboxylic acid, 2,6-spiro[3.3]heptane dicarboxylic acid, 1,3-adamantanedicarboxylic acid, camphoric acid, etc.

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, 4,4'-diphenyl hexafluoropropane dicarboxylic acid, 4,4'-diphenyl prop ... Carboxylic acids, 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, bis(p-carboxyphenyl)dimethylsilane and other dicarboxylic acids.

二唑-3,4-二羧酸、2,3-吡啶二羧酸、2,4-吡啶二羧酸、2,5-吡啶二羧酸、2,6-吡啶二羧酸、3,4-吡啶二羧酸、3,5-吡啶二羧酸等。 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-

Oxadiazole-3,4-dicarboxylic acid, 2,3-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 2,5-pyridinedicarboxylic acid, 2,6-pyridinedicarboxylic acid, 3,4-pyridinedicarboxylic acid, 3,5-pyridinedicarboxylic acid, and the like.

The above-mentioned various dicarboxylic acids may be acyl dihalides or anhydrides. The dicarboxylic acids, especially those that can provide polyamides with linear structures, are better in maintaining the alignment of 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 their acyl dihalides can be preferably used. These compounds also have isomers, and can also be a mixture containing them. Moreover, two or more compounds can also be used in combination. In addition, the dicarboxylic acids used in the present invention are not limited to the above-mentioned exemplary compounds.

When polyamine, polyamine ester, polyurea, and polyamide are obtained by reacting a diamine as a raw material (also described as "diamine component") with a component selected from tetracarboxylic dianhydride (also described as "tetracarboxylic dianhydride component"), tetracarboxylic diester, diisocyanate, and dicarboxylic acid as a raw material, 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 components, tetracarboxylic diesters, diisocyanate, and dicarboxylic acids in an organic solvent.

The reaction between the diamine component and the tetracarboxylic dianhydride component is advantageous in that it is easier to carry out in an organic solvent and does not produce by-products.

The organic solvent used in the above reaction is not particularly limited as long as it can dissolve the generated polymer. In addition, even if it is an organic solvent that 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 become the cause of hydrolysis of the generated polymer, so the organic solvent should be dehydrated and dried.

烷、正己烷、正戊烷、正辛烷、二乙醚、環己酮、碳酸伸乙酯、碳酸伸丙酯、乳酸甲酯、乳酸乙酯、乙酸甲酯、乙酸乙酯、乙酸正丁酯、乙酸丙二醇單乙醚、丙酮酸甲酯、丙酮酸乙酯、3-甲氧基丙酸甲酯、3-乙氧基丙酸甲基乙酯、3-甲氧基丙酸乙酯、3-乙氧基丙酸、3-甲氧基丙酸、3-甲氧基丙酸丙酯、3-甲氧基丙酸丁酯、二乙二醇二甲醚、4-羥基-4-甲基-2-戊酮、2-乙基-1-己醇等。該等有機溶劑可單獨使用亦可混合使用。 As for the organic solvent, for example, there can be mentioned: 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, hexamethylphosphotriamide, γ-butyrolactone, isopropyl alcohol, methoxymethylpentyl alcohol, 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 Alcohol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol Monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, diisobutyl ketone

The organic solvents may be methyl ether, 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 stirring a solution obtained by dispersing or dissolving the diamine component in an organic solvent, and directly adding the tetracarboxylic dianhydride component, or adding it after dispersing or dissolving it 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; a method of alternately adding the tetracarboxylic dianhydride component and the diamine component, etc. Any of these methods can be used. In addition, when the diamine component or the tetracarboxylic dianhydride component is composed of multiple compounds, they can be reacted in a pre-mixed state, or they can be reacted individually in sequence, or low molecular weight polymers that have been reacted individually can be mixed and reacted to produce a high molecular weight polymer.

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. In addition, 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.

The ratio of the total molar number of the tetracarboxylic dianhydride component to the total molar number of the diamine component in the above polymerization reaction 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 the 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-mentioned method. When synthesizing polyamide, the tetracarboxylic acid dianhydride can be replaced with tetracarboxylic acid derivatives such as tetracarboxylic acid or tetracarboxylic acid dihalide of corresponding structure in the same way as the general synthesis method of polyamide, and the corresponding polyamide can be obtained by reacting them in a known manner. In addition, when synthesizing polyurea, diamine can be reacted with diisocyanate. When manufacturing polyamide ester or polyamide, diamine can be reacted with a component selected from tetracarboxylic acid diester and dicarboxylic acid 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 are listed for making polyimide by imidizing the above-mentioned polyamic acid: thermal imidization by directly heating the solution of polyamic acid; 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 preferable, in terms of improving the voltage retention rate. On the other hand, in terms of suppressing the whitening property, that is, suppressing the precipitation of the polymer in the varnish, it is preferably 70% or less. Considering both properties, 40-80% is more preferable.

The temperature for thermal imidization of polyamine in solution is usually 100~400℃, preferably 120~250℃, and it is better to implement it while removing 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, and stirring the solution at -20 to 250°C, preferably 0 to 180°C. 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 them, pyridine is preferred because it has a moderate alkalinity for the reaction to proceed. Acid anhydrides include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, etc. Among them, acetic anhydride is preferred because purification after the reaction is easy. 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 is put into a poor solvent and precipitated. The poor solvent used for precipitation generation can be listed as: 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 normal pressure or reduced pressure at room temperature or under heating. In addition, if the polymer recovered by precipitation is repeatedly dissolved in an organic solvent and re-precipitated and recovered 2 to 10 times, the impurities in the polymer can be reduced. Examples of poor solvents at this time include alcohols, ketones, hydrocarbons, etc. If three or more poor solvents selected from these are used, the efficiency of purification will be further improved, so it is better.

Furthermore, when the above-mentioned 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 other than the polymer containing an organic group that induces free radical polymerization. In this case, the content of other polymers in all polymer components is preferably 5-95% by mass, and more preferably 30-70% by mass.

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

The polymer used in the present invention for obtaining the free radical generating film by applying a composition of a compound having a free radical generating group and a polymer and curing it to form a film, and fixing it in the film, can be selected from the group consisting of a polyimide precursor obtained by the above-mentioned production method, and a polymer consisting of polyimide, polyurea, polyamide, polyacrylate, polymethacrylate, etc., and at least one polymer obtained by using a diamine having a site for free radical polymerization as 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 free radical generating group added at this time can be listed as follows.

啉基丙烷-1-酮、2-苄基-2-二甲基胺基-1-(4-

啉基苯基)-丁烷-1-酮、4-二甲基胺基苯甲酸乙酯、4-二甲基胺基苯甲酸異戊酯、4,4’-二(第三丁基過氧化羰基)二苯甲酮、3,4,4’-三(第三丁基過氧化羰基)二苯甲酮、2,4,6-三甲基苯甲醯基二苯基氧化膦、2-(4’-甲氧基苯乙烯基)-4,6-雙(三氯甲基)-s-三

、2-(3’,4’-二甲氧基苯乙烯基)-4,6-雙(三氯甲基)-s-三

、2-(2’,4’-二甲氧基苯乙烯基)-4,6-雙(三氯甲基)-s-三

、2-(2’-甲氧基苯乙烯基)-4,6-雙(三氯甲基)-s-三

、2-(4’-戊基氧基苯乙烯基)-4,6-雙(三氯甲基)-s-三

、4-[對N,N-二(乙氧基羰基甲基)]-2,6-二(三氯甲基)-s-三

、1,3-雙(三氯甲基)-5-(2’-氯苯基)-s-三

、1,3-雙(三氯甲基)-5-(4’-甲氧基苯基)-s-三

、2-(對二甲基胺基苯乙烯基)苯并

唑、2-(對二甲基胺基苯乙烯基)苯并噻唑、2-巰基苯并噻唑(mercaptobenzothiazole)、3,3’-羰基雙(7-二乙基胺基香豆素)、2-(鄰氯苯基)-4,4’,5,5’-四苯基-1,2’-聯咪唑、2,2’-雙(2-氯苯基)-4,4’,5,5’-肆(4-乙氧基羰基苯基)-1,2’-聯咪唑、2,2’-雙(2,4-二氯苯基)-4,4’,5,5’-四苯基-1,2’-聯咪唑、 2,2’雙(2,4-二溴苯基)-4,4’,5,5’-四苯基-1,2’-聯咪唑、2,2’-雙(2,4,6-三氯苯基)-4,4’,5,5’-四苯基-1,2’-聯咪唑、3-(2-甲基-2-二甲基胺基丙醯基)咔唑、3,6-雙(2-甲基-2-

啉基丙醯基)-9-正十二烷基咔唑、1-羥基環己基苯基酮、雙(5-2,4-環戊二烯-1-基)-雙(2,6-二氟-3-(1H-吡咯-1-基)-苯基)鈦、3,3’,4,4’-四(第三丁基過氧化羰基)二苯甲酮、3,3’,4,4’-四(第三己基過氧化羰基)二苯甲酮、3,3’-二(甲氧基羰基)-4,4’-二(第三丁基過氧化羰基)二苯甲酮、3,4’-二(甲氧基羰基)-4,3’-二(第三丁基過氧化羰基)二苯甲酮、4,4’-二(甲氧基羰基)-3,3’-二(第三丁基過氧化羰基)二苯甲酮、2-(3-甲基-3H-苯并噻唑-2-亞基)-1-萘-2-基-乙酮、或2-(3-甲基-1,3-苯并噻唑-2(3H)-亞基)-1-(2-苯甲醯基)乙酮等。該等化合物可單獨使用，亦可將2種以上混合使用。 The compound that generates radicals by light is not particularly limited as long as it is a compound that initiates radical polymerization upon irradiation with light. Examples of such free radical photopolymerization initiators include benzophenone, Michler's ketone, 4,4'-bis(diethylamino)benzophenone, oxanthrone, thioxanthrone, isopropyloxanthrone, 2,4-diethylthioxanthrone, 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methyl-4'-isopropylpropiophenone, 1-hydroxycyclohexylphenyl ketone, isopropylphenyl ether, isobutylphenyl ether, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, camphorquinone, benzanthrone, 2-methyl-1-[4-(methylthio)phenyl]-2-

1-O-Phenylpropane-2-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-tris( ...

, 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)benzo

azole, 2-(p-dimethylaminophenyl)benzothiazole, 2-mercaptobenzothiazole, 3,3'-carbonylbis(7-diethylaminocoumarin), 2-(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-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 ...1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-1-nitro-2-acetyl)-

Furthermore, even when the above-mentioned free radical generating film is composed of a polymer containing an organic group that induces free radical polymerization, a compound having the above-mentioned free radical generating group may be contained for the purpose of promoting free radical polymerization when irradiated with light.

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

In addition, it is advisable to mix a solvent that improves the uniformity and smoothness of the coating with an organic solvent that has high solubility for the components contained in the free radical generating film forming composition.

Examples of solvents for improving the uniformity and smoothness of the coating include 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 ... Alcohol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3- Ethoxypropionic acid, 3-methoxypropionic acid, 3-methoxypropionic acid propyl ester, 3-methoxypropionic acid butyl ester, 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, 2-ethyl-1-hexanol, etc. These solvents can also be mixed in multiple ways. 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-generating film-forming composition may also contain ingredients other than those mentioned above. Examples thereof include: compounds that improve the uniformity of film thickness and surface smoothness when applying the radical-generating film-forming composition; compounds that improve the adhesion between the radical-generating film-forming composition and the substrate; compounds that further improve the film strength of the radical-generating film-forming composition, etc.

Examples of compounds that improve the uniformity of film thickness and surface smoothness include fluorine-based surfactants, silicone-based surfactants, and nonionic surfactants. More specifically, examples include EFTOP EF301, EF303, and EF352 (manufactured by Mitsubishi Materials Electronic Chemicals), Megafac F171, F173, and R-30 (manufactured by DIC), Fluorad FC430 and FC431 (manufactured by 3M), AsahiGuard AG710, surflon S-382, SC101, SC102, SC103, SC104, SC105, and SC106 (manufactured by AGC), and the like. When using such surfactants, the usage ratio is preferably 0.01 to 2 parts by mass, and more preferably 0.01 to 1 part by mass, relative to 100 parts by mass of the total amount of polymers 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 trimeth ... 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 addition, in order to further enhance the strength of the free radical generating film, phenol compounds such as 2,2'-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane and tetrakis(methoxymethyl)bisphenol may also be added. When such compounds are used, the amount is preferably 0.1 to 30 parts by mass, and more preferably 1 to 20 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.

In addition, in addition to the above, dielectrics and conductive substances may be added to the radical generating film forming composition to change the electrical properties such as the dielectric constant and conductivity of the radical generating film within the scope that does not impair the effect of the present invention.

<Method for preparing free radical generating film>

The free radical generating film of the present invention is obtained by 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, and the cured film can be directly used as a free radical generating film. In addition, the cured film can also be rubbed, or irradiated with polarized light or light of a specific wavelength, or treated with ion beams, etc. For the PSA alignment film, UV can also be irradiated on the liquid crystal display element after liquid crystal filling.

When making a free radical generating film, the irradiation light used is not particularly limited and can be appropriately selected according to the purpose. For example, light with a peak at 240-400nm can be cited. Light with a peak at 250-365nm is more preferred, and light with a peak at 250-360nm is particularly preferred. More specifically, for example, light with a peak near 254nm or near 313nm can be cited.

In addition, known cutoff filters can be used to cut off light of a specific wavelength, above or below a specific wavelength as needed.

The substrate on which the radical generating film-forming composition is applied is not particularly limited as long as it is a highly transparent substrate, and is not limited to an electrode.

For example, an ideal state can be exemplified by forming a transparent electrode on a substrate for driving liquid crystal.

To cite specific examples, substrates with transparent electrodes formed on glass plates, polycarbonate, poly(meth)acrylate, polyether sulfone, polyarylate, polyurethane, polysulfone, polyether, polyether ketone, trimethylpentene, polyolefin, polyethylene terephthalate, (meth)acrylonitrile, triacetyl cellulose, 2,3-butanedione cellulose, acetate butyrate cellulose, and other plastic plates can be cited.

The substrate that can be used for IPS mode liquid crystal display elements can also use standard IPS comb electrodes, electrode patterns such as PSA herringbone electrodes, and protrusion patterns such as MVA.

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

When manufacturing a transmissive liquid crystal display element, a substrate as described above is generally used. However, when manufacturing a reflective liquid crystal display element, if it is a single-sided substrate, an opaque substrate such as a silicon wafer can also be used. In this case, the electrode formed on the substrate can also use a material that reflects light, such as aluminum.

Methods for applying the free radical-generating film-forming composition include spin coating, printing, inkjet, inkjet, roller coating, etc. However, considering productivity, transfer printing is widely used in industry and can also be used ideally in the present invention.

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

The film formed by applying the free radical film-forming composition by the above method, the so-called free radical film, can be calcined to make a hardened film. At this time, the calcination temperature can usually be carried out at any temperature of 100~350℃, preferably 140~300℃, more preferably 150~230℃, and more preferably 160~220℃. The calcination time can usually be carried out at any time of 5~240 minutes. It is preferably 10~90 minutes, and more preferably 20~90 minutes. Heating can use commonly known methods, such as heating plates, hot air circulation ovens, IR (infrared) ovens, belt furnaces, etc.

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

In the above manner, a first substrate having a free radical generating film can be obtained, but the free radical generating film can be subjected to a uniaxial alignment treatment. Methods for performing a uniaxial alignment treatment include photoalignment, oblique evaporation, friction, and uniaxial alignment treatment using a magnetic field.

When the orientation treatment is performed by rubbing in one 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 having a comb-tooth electrode formed, the direction is selected by utilizing the electrical properties of the liquid crystal, but when using a liquid crystal having positive dielectric anisotropy, the rubbing direction is preferably approximately the same as the extension direction of the comb-tooth electrode.

<Liquid crystal composition containing liquid crystal and free radical polymerizable compound>

The liquid crystal display element of the present invention is made using a liquid crystal composition containing liquid crystal and a free radical polymerizable compound.

The polymerizable compound used with liquid crystal is not particularly limited as long as it is a free radical polymerizable compound, and may be, 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 free radical polymerizable compounds is preferably a compound that is compatible with liquid crystal and has one polymerizable unsaturated bond in one molecule, that is, a compound having a monofunctional free radical polymerizable group is preferred.

In addition, the polymerization reactive group of the free radical polymerizable compound is preferably a polymerizable group selected from the following structures.

[Chemistry 24]

In the formula, * represents the bonding site with the compound molecule other than the polymerizable unsaturated bond. ^Rb represents an alkyl group having 3 to 20 carbon atoms, and 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, and the alkyl group of ^Rb represents a straight chain, branched, or cyclic alkyl group.

In addition, in the liquid crystal composition containing liquid crystal and a radical polymerizable compound, it is preferred that the radical polymerizable compound be contained in a polymer having a Tg of 100°C or less obtained by polymerizing the radical polymerizable compound.

Compounds having a monofunctional free radical polymerization reactive group are those having unsaturated bonds that can undergo free radical polymerization in the presence of organic free radicals, for example: 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 (for example, o-, m-, p-methoxystyrene, o-, m-, p-tert-butoxystyrene, o-, m-, p-chloromethylstyrene, etc.), vinyl esters (e.g., vinyl acetate, vinyl propionate, vinyl benzoate, vinyl acetate, etc.), vinyl ketones (e.g., vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone, etc.), N-vinyl compounds (e.g., N-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, hexachloropropylene, vinyl fluoride, etc.), etc., but not limited to these. These various free radical polymerizable monomers can be used alone or in combination of two or more. In addition, these should be compatible with liquid crystals.

In addition, the free radical polymerizable compound is preferably a compound represented by the following formula (A).

In formula (A), ^Ra and ^Rb each independently represent an alkyl group having 3 to 20 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, and the alkyl group of ^Ra or ^Rb represents a linear, branched, or cyclic alkyl group.

In addition, for the free radical polymerizable compound represented by formula (A), the one in which E is an ester bond (a bond represented by -C(=O)-O- or -O-C(=O)-) is preferred from the viewpoints of ease of synthesis, compatibility with liquid crystals, and polymerization reactivity. Specifically, the compound preferably has the following structure, but there is no particular limitation.

In formula (A-1) and (A-2), ^Ra and ^Rb each independently represent an alkyl group having 3 to 20 carbon atoms, and the alkyl groups of ^Ra and ^Rb each independently represent a linear, branched, or cyclic alkyl group.

The free radical polymerizable compound of the present invention may also have a vertical alignment group.

The vertical alignment group possessed by the radical polymerizable compound used in the present invention may be, for example, a group represented by the following formula [S1].

In formula [S1], ^X1 and ^X2 independently represent a single bond, -( _CH2 ) _a- (a is an integer of 1 to 15), -CONH-, -NHCO-, -CON( _CH3 )-, -NH-, -O-, -COO-, -OCO-, or -(( _CH2 ) _a1 - _A1 ) _m1- (a plurality of A1s each independently represent an integer of 1 to 15, a plurality of A1s _each independently represent an oxygen atom or -COO-, and _m1 is 1 or 2). Among them, from the viewpoint of availability of raw materials and ease of synthesis, a single bond, -( _CH2 ) _a- (a is an integer of 1 to 15), -O-, _-CH2O- , or -COO- is preferred. More preferably, it is a single bond, -(CH ₂ ) _a - (a is an integer of 1 to 10), -O-, -CH ₂ O- or -COO-.

^G1 and ^G2 are independently a divalent cyclic group selected from a divalent aromatic group having 6 to 12 carbon atoms or a divalent alicyclic group having 3 to 8 carbon atoms. Any hydrogen atom on the above cyclic group may be substituted by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorinated alkyl group having 1 to 3 carbon atoms, a fluorinated alkoxy group having 1 to 3 carbon atoms, or a fluorine atom. m and n are independently integers of 0 to 3, and the total of these integers is 0 to 4. ^R1 is an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an alkoxyalkyl group having 2 to 20 carbon atoms. Any hydrogen atom in these groups may be substituted by fluorine. However, when the total of m and n is 0, ^R1 may be a group having a steroid skeleton.

Examples of divalent aromatic groups with 6 to 12 carbon atoms include phenylene, biphenylene, and naphthylene. Examples of divalent alicyclic groups with 3 to 8 carbon atoms include cyclopropylene, cyclohexylene, and the like.

The ideal concrete example of formula [S1] can be listed as the following structures of formula [S1-x1]~[S1-x7].

In formulas [S1-x1] to [S1-x7], ^R1 is an alkyl group having 1 to 20 carbon atoms, ^Xp represents -( _CH2 ) _a- (a is an integer of 1 to 15), _A1 is an oxygen atom or -COO-* (however, the atom marked with "*" is bonded to ( _CH2 ) _a2 ), _A2 is an oxygen atom or *-COO- (however, the atom marked with "*" is bonded to (CH2) _a2 ), _{a1 and a3} are each independently an integer of 0 or 1, _a2 is an integer of 2 to 10, and Cy is 1,4-cyclohexylene or 1,4-phenylene.

An ideal specific example of the above-mentioned base having a steroid skeleton can be listed as the following formula [S3-x].

[Chemistry 29]

In formula [S3-x], Col represents any one of the above formulas [Col1] to [Col4], and G represents any one of the above formulas [G1] to [G2]. * represents a bonding position.

The ideal embodiment of the free radical polymerizable compound of the present invention can be, for example, a free radical polymerizable compound having a vertically oriented group in which the vertically oriented group [S1] is bonded to any of the above-mentioned free radical polymerizable groups.

These various free radical polymerizable monomers can be used alone or in combination of two or more. In addition, they should be compatible with liquid crystals.

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

In addition, 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.

<LCD cell>

The liquid crystal display element of the present invention can be manufactured into the unit cell structure described below, for example.

After forming a free radical generating film on a substrate using the above method, the first substrate and the second substrate having the free radical generating film are arranged in such a way that the free radical generating film on the first substrate faces the second substrate, and a liquid crystal composition containing liquid crystal and free radical polymerizable compounds is filled between the first substrate and the second substrate to produce a liquid crystal cell.

The liquid crystal display element manufactured in the present invention can use the liquid crystal cell obtained in this way.

To explain the method for making the above-mentioned liquid crystal cell in more detail, the free radical generating film on the first substrate is arranged to face the second substrate, and then the two substrates are fixed with a sealant by clamping a spacer, and a liquid crystal composition containing liquid crystal and a free radical polymerizable compound is injected between the first and second substrates and sealed, thereby obtaining a liquid crystal cell.

The size of the spacer used at this time is usually 1~30μm, preferably 2~10μm.

There is no particular limitation on the method of injecting the liquid crystal composition containing liquid crystal and free radical polymerizable compounds, and examples thereof include: a vacuum method of injecting a mixture containing liquid crystal and polymerizable compounds after depressurizing the prepared liquid crystal cell; a dripping method of dripping a mixture containing liquid crystal and polymerizable compounds and then sealing the mixture.

The second substrate is preferably formed with an alignment film for aligning the liquid crystal.

The alignment film can be a known liquid crystal alignment film or any of the free radical generating films of the present invention, and can be appropriately selected according to the purpose.

The alignment film formed on the second substrate may be subjected to uniaxial alignment treatment.

As described later, for example, when an out-of-plane alignment region is formed in a liquid crystal display element, it is appropriate to form a free radical generating film on the second substrate.

In addition, for example, when forming an in-plane alignment region or a tilted alignment region in a liquid crystal display element, it is appropriate to form a liquid crystal alignment film for horizontal alignment that has been processed by uniaxial alignment on the second substrate.

<Formation of in-plane alignment, out-of-plane alignment, and tilted alignment regions>

A liquid crystal cell is formed by using a substrate formed with a free radical generating film and arranging a mixture (liquid crystal composition) containing liquid crystal and a free radical polymerizable compound between the substrates, and irradiating light sufficient to cause the free radical polymerizable compound to undergo a polymerization reaction.

As described above, the present invention forms a radical-generating film with anchoring force on a substrate, and irradiates light to the radical-generating film in the area where the anchoring force is to be maintained while a liquid crystal containing a specific polymerizable compound is in contact with the radical-generating film. The polymerizable compound is polymerized, and the liquid crystal is vertically aligned, and as a result, an out-of-plane alignment (vertical alignment) area is formed in the area irradiated with light.

Here, the irradiated light may be light having a peak at 240-400nm. In addition, it is preferred to irradiate light of a wavelength that increases the absorbance at the part where the photo-free radical is generated, and the light having a peak at 250-365nm is more preferred, and the light having a peak at 250-360nm is particularly preferred.

More specifically, for example, light having a peak near 313 nm can be used. In addition, a known cutoff filter can be used to cut off light of a specific wavelength, above or below a specific wavelength, as needed.

The light exposure is usually 0.01~30J, preferably less than 10J. The less light exposure, the more it can suppress the reliability reduction caused by the damage of the components constituting the liquid crystal display element, and it is more ideal to improve the manufacturing takt by reducing the light exposure time.

In addition, heating can also be performed during light irradiation. The heating temperature during light irradiation should preferably be within the temperature range where the introduced liquid crystal exhibits liquid crystal properties, usually above 40°C. It is preferred to heat at a temperature below the temperature at which the liquid crystal changes to the isotropic phase.

Furthermore, when irradiating light to allow the radical polymerizable compound to undergo polymerization, it is better to proceed in a state without applying a voltage and in a state without an electric field.

On the other hand, when the liquid crystal cell is irradiated with light, if a mask is placed outside the liquid crystal cell and light is irradiated through the mask, the unexposed portion (= the area where no free radicals are generated) will form an in-plane alignment (horizontal alignment) area, and the exposed portion will form an out-of-plane alignment (vertical alignment) area as described above.

There are no special restrictions on the pattern shape and pattern size of the mask used, and they can be appropriately selected according to the purpose. As for the pattern shape, for example, line pattern shape, line/space (L/S) pattern shape, dot shape, etc. can be listed. As for the pattern size, a micron-sized pattern can be made. For example, if a mask with a 5μm pitch L/S pattern shape is used, a 5μm pitch alignment pattern can be formed.

In addition, by irradiating the radical generating film with light before assembling the cell of the liquid crystal cell and deactivating the radical generating ability of the radical generating film, an in-plane alignment (horizontal alignment) region can also be formed. By irradiating the radical generating film with light in advance to eliminate the radical generating ability, a state of anchoring strength that is always maintained in the in-plane direction can be created. That is, by using the radical generating film after deactivating the radical generating ability to make a liquid crystal cell and irradiating the liquid crystal cell with light, an in-plane alignment (horizontal alignment) region can also be formed in the region where the radical generating ability is deactivated.

In addition, the light used to deactivate the free radical generating ability of the free radical generating film can be exemplified by light having a peak at 240-400nm. Furthermore, the light is preferably light having a peak at 250-365nm, and is particularly preferably light having a peak at 250-360nm. More specifically, for example, light having a peak near 313nm can be used. In addition, light having a specific wavelength, or light above or below a specific wavelength, can be cut off by using a known cutoff filter as needed.

The amount of light exposure is usually 0.01~30J, preferably less than 10J.

In the above-mentioned unexposed part and the area where the free radical generating ability is inactivated, in order to achieve good surface alignment of the liquid crystal, it is advisable to apply uniaxial alignment treatment to the free radical generating film.

Furthermore, in the above-mentioned unexposed part and the area where the free radical generating ability is inactivated, in order to achieve good surface alignment of the liquid crystal, the polymer contained in the free radical generating film forming composition in the free radical generating film should preferably not contain a part having a vertical alignment function.

As described above, when a free radical generating film is used to form an out-of-plane alignment region, a unit cell can be made using the first and second substrates formed with the free radical generating film, and after injecting a liquid crystal composition containing a predetermined free radical polymerizable compound, light is irradiated from the outside of the unit cell to polymerize the polymerizable compound, thereby causing the liquid crystal to be vertically aligned.

On the other hand, when a free radical generating film is used to form an in-plane alignment region, the first and second substrates formed with the free radical generating film can be irradiated with light before cell assembly to inactivate the free radical generating ability, and then the cell assembly can be performed. In this way, even if the manufactured liquid crystal cell is irradiated with light, the interface reaction can still be suppressed.

Alternatively, a photomask may be placed outside the liquid crystal cell to prevent the free radical generating ability from being inactivated, and light may be irradiated through the photomask, thereby preventing free radicals from being generated in the unexposed portion and inducing interface reactions.

In a liquid crystal display device, a tilt orientation region can be formed by manufacturing a liquid crystal cell in a manner where the in-plane orientation and the out-of-plane orientation are opposite to each other.

For example, when a free radical generating film is used on both the first substrate and the second substrate, a tilted alignment region can be produced by appropriately combining the above-mentioned method of forming an out-of-plane alignment and the method of forming an in-plane alignment.

More specifically, for example, by using a radical generating film to form an out-of-plane alignment on one of the first substrate and the second substrate, and using a radical generating film whose radical generating ability is deactivated to form an in-plane alignment on the other substrate, a tilt orientation region can be formed.

Furthermore, a free radical generating film may be used on one of the first substrate and the second substrate, and a liquid crystal alignment film without free radical generating ability may be used on the other substrate. When a liquid crystal alignment film without free radical generating ability is used on the other substrate, the liquid crystal alignment film may be an in-plane alignment film or an out-of-plane alignment film. By combining the above-mentioned method of using a free radical generating film to produce in-plane alignment and out-of-plane alignment, various patterns composed of various combinations of in-plane alignment regions, tilted alignment regions, and out-of-plane alignment regions may be formed.

The liquid crystal alignment film should be treated with uniaxial alignment.

In addition, in the manufacturing method of the liquid crystal display element of the present invention, the content of the free radical polymerizable compound contained in the liquid crystal composition and the irradiation amount when the liquid crystal cell is irradiated with light can also be adjusted to make the liquid crystal tilted instead of vertically aligned, and form a tilted alignment area.

As described above, according to the manufacturing method of the liquid crystal display element of the present invention, a liquid crystal display element having a free radical generating film can be manufactured in which at least two regions of the in-plane alignment region, the out-of-plane alignment region, and the tilted alignment region are patterned.

<Liquid crystal display element>

According to the manufacturing method of the present invention, a liquid crystal display element having at least two regions of the in-plane alignment region, the out-of-plane alignment region, and the tilted alignment region patterned can be manufactured in industry with good productivity. Therefore, the liquid crystal display element manufactured using the manufacturing method of the present invention can be widely used in practice.

For example, by setting a reflective electrode, a transparent electrode, a λ/4 plate, a polarizing film, a color filter layer, etc. on the liquid crystal cell as needed according to conventional methods, it can be used as a reflective liquid crystal display element.

In addition, by setting a backlight source, a polarizing plate, a λ/4 plate, a transparent electrode, a polarizing film, a color filter layer, etc. on the liquid crystal cell as needed according to conventional methods, it can be used as a transmissive liquid crystal display element.

FIG10 is a schematic cross-sectional view showing an example of a liquid crystal display element of the present invention, which is an example of an IPS mode liquid crystal display element.

In the liquid crystal display element 101 illustrated in FIG. 10 , a liquid crystal composition 103 is sandwiched between a comb-tooth electrode substrate 102 having a free radical generating film 102c and an opposing substrate 104 having a liquid crystal alignment film 104a. The comb-tooth electrode substrate 102 comprises: a substrate 102a, a plurality of linear electrodes 102b formed on the substrate 102a and arranged in a comb shape, and a free radical generating film 102c formed on the substrate 102a in a manner covering the linear electrodes 102b. The opposing substrate 104 comprises: a substrate 104b, and a liquid crystal alignment film 104a formed on the substrate 104b.

In the liquid crystal display element 101, when a voltage is applied to the linear electrodes 102b, an electric field is generated between the linear electrodes 102b as indicated by the electric field lines L.

FIG11 is a schematic cross-sectional view showing another example of the liquid crystal display element of the present invention, which is an example of an FFS mode liquid crystal display element.

In the liquid crystal display element 101 illustrated in FIG11 , a liquid crystal composition 103 is sandwiched between a comb-tooth electrode substrate 102 having a radical generating film 102h and a counter substrate 104 having a liquid crystal alignment film 104a. The comb-tooth electrode substrate 102 has a substrate 102d, a surface electrode 102e formed on the substrate 102d, an insulating film 102f formed on the surface electrode 102e, a plurality of linear electrodes 102g formed on the insulating film 102f and arranged in a comb-tooth shape, and a radical generating film 102h formed on the insulating film 102f in a manner covering the linear electrodes 102g. The counter substrate 104 comprises: a substrate 104b and a liquid crystal alignment film 104a formed on the substrate 104b.

In the liquid crystal display element 101, when a voltage is applied to the surface electrode 102e and the linear electrode 102g, an electric field is generated between the surface electrode 102e and the linear electrode 102g as indicated by the electric field lines L.

[Implementation example]

The present invention is further described in detail with reference to the following embodiments, but the scope of the present invention is not limited to these embodiments.

In the embodiments, the abbreviations of the compounds used in the polymerization of polymers and the preparation of free radical-generating film-forming compositions and the methods for evaluating their properties are as follows.

[Chemistry 30]

[Chemistry 31]

NMP: N-methyl-2-pyrrolidone,

BCS: Butyl Cellulose

<Viscosity measurement>

For polyamide solution, use E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) to measure the viscosity at 25°C with a sample volume of 1.1 mL and a conical rotor TE-1 (1°34’, R24).

<Determination of molecular weight>

The molecular weight is measured using a room temperature GPC (gel permeation chromatography) device, and the number average molecular weight (Mn) and weight average molecular weight (Mw) are calculated in the form of polyethylene glycol and polyethylene oxide conversion values.

GPC device: GPC-101 (manufactured by Showa Denko Co., Ltd.), column: GPC KD-803, GPC KD-805 (manufactured by Showa Denko Co., Ltd.) in series, column temperature: 50°C, eluent: N,N-dimethylformamide (for additives, lithium bromide monohydrate (LiBr.H2O) is 30mmol/L, phosphoric acid-anhydrous crystals (o-phosphoric acid) is 30mmol/L, tetrahydrofuran (THF) is 10mL/L), flow rate: 1.0mL/min

Standard samples for calibration line preparation: TSK standard polyethylene oxide (molecular weight; approximately 900,000, 150,000, 100,000 and 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight; approximately 12,000, 4,000 and 1,000) (manufactured by Polymer Laboratories).

<Determination of imidization rate>

20 mg of polyimide powder was placed in an NMR sample tube (NMR standard sample tube φ5 manufactured by Kusano Scientific Co., Ltd.), and 0.53 mL of deuterated dimethyl sulfoxide (DMSO-d ₆ , 0.05 mass% TMS (tetramethylsilane) mixture) was added, and ultrasonicated to completely dissolve. The solution was measured for 500 MHz proton NMR using a measuring device (JEOL, JNW-ECA500).

The imidization rate is determined by taking the proton from the structure that does not change before and after imidization as the reference proton, and using the peak accumulation value of the proton and the peak accumulation value of the proton from the NH of the amide group appearing around 9.5~10.0ppm, and calculating 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 reference proton to the number of 1 NH proton of the amide group of polyamide (imidization rate is 0%).

(Synthesis of compound DA-4)

Compound DA-4 was obtained using the following method.

[Chemistry 32]

<Step 1>

To 4,4'-dinitro-[1,1'-biphenyl]-2,2'-dicarboxylic acid (20.0 g, 60.2 mmol), tetrahydrofuran (120 g), 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (28.4 g, 126 mmol), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (28.0 g, 181 mmol), and N,N-dimethylaminopyridine (0.735 g, 6.02 mmol) were added, and stirred at room temperature overnight. After the reaction was completed, the mixture was extracted twice with water/chloroform, and the obtained organic phase was concentrated to obtain a syrupy brown oil. It was purified by column chromatography with a mixed solvent of ethyl acetate/hexane = 3/1 (volume ratio). The obtained fraction was concentrated to a yellow transparent oil, which was allowed to stand for a long time, and white crystals precipitated from the oil. The precipitated crystals were washed with a slurry of a mixed solvent of ethyl acetate/hexane = 3/1 (volume ratio), filtered and dried to obtain compound (DA-4-1) (yield: 29.8 g, 40.0 mmol, yield 67%).

¹ H-NMR (500MHz) in DMSO-d ₆ :8.57(d,J=2.5Hz,2H),8.37(dd,J=8.5Hz,2.5Hz,2H),8.18(d,J=9.0Hz,4H),7.55(d,J=8.5Hz,2H),6.8 5(d,J=9.0Hz,4H),5.631(s,2H),4.39-4.35(m,4H),4.02-3.99(m,2H),3.96-3.94(m,2H),1.40(s,12H).

<Step 2>

For the compound (DA-4-1) (29.8 g, 40.0 mmol) obtained in step 1, tetrahydrofuran (240 g) was added, and nitrogen was replaced. Then, 3% platinum carbon (water-containing) (2.38 g) was added and nitrogen was replaced. A hydrogen sampling bag (tedlar bag) was installed and stirred at room temperature for about 17 hours. After the reaction was completed, the platinum carbon was removed through a membrane filter, and it was concentrated and dried to obtain compound (DA-4) (yield: 27.4 g, 40.0 mmol, yield quant).

¹ H-NMR (500MHz) in DMSO-d ₆ :8.20(dd,J=7.1Hz,1.9Hz,4H),6.99(d,J=2.5Hz,2H),6.92(dd,J=7.3Hz,1.9Hz,4H),6.80(d,J=8.2Hz,2H), 6.67(dd,J=8.2Hz,2.5Hz,2H),5.64(s,2H),5.24(s,4H),4.22(t,J=4.5Hz,4H),4.00(br,4H),1.39(s,12H).

(Polymerization of polymers and preparation of free radical-generating film-forming compositions)

<Synthesis Example 1> Synthesis of TC-1(50)TC-2(50)/DA-1(70)DA-2(30) polyimide

In a 100mL 4-necked flask equipped with a nitrogen inlet tube, air cooling tube, and mechanical stirrer, weigh 3.78g (35.0mmol) of DA-1 and 4.96g (15.0mmol) of DA-2, add 35.0g of NMP and stir in a nitrogen environment to completely dissolve. After confirming the dissolution, add 6.26g (25.0mmol) of TC-2 and 25.0g of NMP, and heat and stir at 60℃ for 3 hours in a nitrogen environment. After that, add 4.12g (21.0mmol) of TC-1 and 16.5g of NMP, and stir at room temperature for 12 hours. Confirm the polymerization viscosity, and further add TC-1 to make the polymerization viscosity become 1000mPa. s, and obtain a polymer solution with a polyamine concentration of 20 mass %.

In a 200 mL Erlenmeyer flask equipped with a magnetic stirrer, 50.0 g of the polyamine solution obtained above was weighed and 92.9 g of NMP was added to prepare a solution with a solid content of 7% by mass. While stirring, 10.6 g (103 mmol) of acetic anhydride and 3.28 g (41.4 mmol) of pyridine were added. After stirring at room temperature for 30 minutes, the mixture was heated and stirred at 60°C for 3 hours. After that, the solution was returned to room temperature and poured into 500 mL of methanol while stirring to precipitate the solid. After repeating the operation twice, the mixture was air-dried and dried in a vacuum oven set at 60°C to obtain a polyimide powder (PI-1) with a Mn of 11,453, a Mw of 27,655, and an imidization rate of 67.0%.

<Synthesis Example 2> Synthesis of TC-1(50)TC-2(50)/DA-1(50)DA-2(50) polyimide

The amount of the monomers used was changed as shown in Table 1. The same method as in Synthesis Example 1 was used to obtain polyimide powder (PI-2). The polyimide powder had an Mn of 21,959, an Mw of 67,088, and an imidization rate of 62.2%.

<Synthesis Example 3> Synthesis of TC-1(50)TC-2(50)/DA-2(100) polyimide

The amount of the monomer used was changed as shown in Table 1. The same method as in Synthesis Example 1 was used to obtain polyimide powder (PI-3). The polyimide powder had an Mn of 21,959, an Mw of 67,088, and an imidization rate of 72.0%.

<Synthesis Example 4> Polymerization of TC-3(100)/DA-3(50)DA-4(50) polyamine

In a 100mL 4-necked flask equipped with a nitrogen inlet tube, air cooling tube, and mechanical stirrer, 2.44g (10.00mmol) of DA-3 and 6.85g (10.00mmol) of DA-4 were weighed, 52.6g of NMP was added, and stirred in a nitrogen environment to completely dissolve. After confirming the dissolution, 4.21g (18.80mmol) of TC-3 and 23.9g of NMP were added, and heated and stirred at 40°C for 12 hours in a nitrogen environment. The polymerization viscosity was confirmed, and TC-3 was further added to make the polymerization viscosity become 400mPa.s, and a polymerization solution (PAA-1) with a polyamine concentration of 15% by mass was obtained. The Mn of the polyamine is 16,331 and the Mw is 42,999.

<Synthesis Example 5> Synthesis of AC-1(40)AC-2(60) polymethacrylate

In a 100mL 4-necked flask equipped with a nitrogen inlet tube, air cooling tube, and mechanical stirrer, 5.00g (15.0mmol) of AC-1, 6.91g (22.6mmol) of AC-2, and 0.185g (1.13mmol) of AIBN were weighed, and 67.5g of NMP was added and stirred in a nitrogen environment to completely dissolve. The solution was vacuum degassed and heated and stirred at 60°C for 12 hours in a nitrogen environment. After that, the solution was returned to room temperature and injected into 300mL of methanol while stirring to precipitate solids. After repeating the operation twice, the mixture was air-dried and dried in a vacuum oven set at 60°C to obtain polymethacrylate powder (PMA-1) with Mn of 37,197 and Mw of 116,919.

<Preparation of free radical-generating film-forming composition: AL-1>

In a 15mL vial equipped with a magnetic stirrer, 0.90g of the polyimide powder (PI-1) obtained in Synthesis Example 1 was weighed, and 5.10g of NMP was added, and heated and stirred at 50°C to obtain a polymer solution with a solid content concentration of 15% by mass. 6.00g of NMP and 3.00g of BCS were added thereto, and further stirred for 3 hours to obtain the free radical-generating film-forming composition of the present invention: AL-1 (solid content: 6.0% by mass, NMP: 74% by mass, BCS: 20% by mass).

<Preparation of free radical-generating film-forming composition: AL-2>

Using the polyimide powder (PI-2) obtained in Synthesis Example 2, the free radical generating film forming composition of the present invention: AL-2 (solid content: 6.0 mass%, NMP: 74 mass%, BCS: 20 mass%) was obtained by the same method as that of AL-1.

<Preparation of free radical-generating film-forming composition: AL-3>

Using the polyimide powder (PI-3) obtained in Synthesis Example 3, the free radical-generating film-forming composition of the present invention: AL-3 (solid content: 6.0 mass%, NMP: 74 mass%, BCS: 20 mass%) was obtained by the same method as that of AL-1.

<Preparation of free radical-generating film-forming composition: AL-4>

In a 15 mL vial equipped with a magnetic stirrer, 6.00 g of the polyamine (PAA-1) obtained in Synthesis Example 4 was weighed, and 6.00 g of NMP and 3.00 g of BCS were added and stirred for 3 hours to obtain the free radical-generating film-forming composition of the present invention: AL-4 (solid content: 6.0 mass%, NMP: 74 mass%, BCS: 20 mass%).

<Preparation of free radical-generating film-forming composition: AL-5>

In a 15mL vial equipped with a magnetic stirrer, 0.27g of the polymethacrylate powder (PMA-1) obtained in Synthesis Example 5 and 0.63g of the polyimide powder (PI-3) obtained in Synthesis Example 3 were weighed, and 5.10g of NMP was added, and heated and stirred at 60°C to obtain a polymer solution with a solid content concentration of 15% by mass. 6.00g of NMP and 3.00g of BCS were added thereto, and further stirred for 3 hours to obtain the free radical-generating film-forming composition of the present invention: AL-5 (solid content: 6.0% by mass, NMP: 74% by mass, BCS: 20% by mass).

<Preparation of free radical-generating film-forming composition: AL-6>

In a 15mL vial equipped with a magnetic stirrer, 0.45g of the polymethacrylate powder (PMA-1) obtained in Synthesis Example 5 and 0.45g of the polyimide powder (PI-3) obtained in Synthesis Example 3 were weighed, and 5.10g of NMP was added, and heated and stirred at 60°C to obtain a polymer solution with a solid content concentration of 15% by mass. 6.00g of NMP and 3.00g of BCS were added thereto, and further stirred for 3 hours to obtain the free radical-generating film-forming composition of the present invention: AL-6 (solid content: 6.0% by mass, NMP: 74% by mass, BCS: 20% by mass).

<Preparation of non-free radical film-forming composition: AL-7>

Using the polymethacrylate powder (PMA-1) obtained in Synthesis Example 5, the non-radical film-forming composition of the present invention: AL-7 (solid content: 6.0 mass%, NMP: 74 mass%, BCS: 20 mass%) was obtained by the same method as that of AL-1.

The composition of polyamine and polyimide is shown in Table 1 below.

The composition of polymethacrylate is shown in Table 2 below.

The compositions of the free radical film-forming composition and the non-free radical film-forming composition are shown in Table 3 below.

The composition of liquid crystal species is shown in Table 4 below.

[Table 4]

(Polymerizable compound)

The polymerizable compounds (additives) listed in Table 4 are obtained in the following manner.

<Synthesis Example 1 of Polymerizable Compound>

Synthesis of Iconate (IC-12)

In a 4-necked flask equipped with a Dean-Stark tube, 30.0 g (231 mmol) of itaconic acid and 81.6 g (438 mmol) of 1-dodecanol were weighed and completely dissolved in cyclohexane (700 mL). After confirming the dissolution, 1.13 g (11.5 mmol) of concentrated sulfuric acid and 0.51 g (2.31 mmol) of dibutylhydroxytoluene (BHT) were added, and the mixture was heated and stirred at 120°C for 24 hours in a nitrogen atmosphere. After confirming the completion of the reaction by nuclear magnetic resonance spectroscopy ( ¹ H-NMR spectroscopy), 100 mL of n-hexane was added to the reaction solution, and the mixture was washed three times with 100 g of a 10% sodium carbonate aqueous solution and three times with 100 mL of pure water, and dried with anhydrous magnesium sulfate. After filtration and concentration, vacuum drying was performed to obtain 78.0 g (167 mmol: yield 76.3%) of a white solid. The structure was confirmed to be the target compound by ¹ H-NMR spectrum. The measurement data are shown below.

¹ H-NMR (400MHz, 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(36H), 0.96-0.83(6H)

<Synthesis Example 2 of Polymerizable Compounds>

Synthesis of dihexyl acrylamide (AAA-C6C6)

In a 4-necked flask, 33.3 g (180 mmol) of dihexylamine and 27.3 g (270 mmol) of triethylamine were weighed, and 500 mL of THF was added to completely dissolve them at room temperature. After confirming the dissolution, the reaction vessel was ice-cooled and kept at 0°C, and 17.9 g (198 mmol) of acryloyl chloride was slowly added dropwise. After confirming the completion of the reaction by nuclear magnetic resonance spectroscopy ( ¹ H-NMR spectrum), 100 mL of ethyl acetate was added to the reaction solution, and the mixture was washed three times with 100 g of a 10% sodium carbonate aqueous solution and three times with 100 mL of pure water, and dried with anhydrous magnesium sulfate. After filtering and concentration, vacuum drying was performed to obtain 33.6 g (140 mmol: yield 78.1%) of a transparent oily liquid. The structure was confirmed to be the target compound by ¹ H-NMR spectroscopy. The measurement data are shown below.

¹ H-NMR (400MHz, DMSO-d ₆ )δ: 6.62(1H), 6.04(1H), 5.58(1H), 3.20-4.00(4H), 3.35-3.25(4H), 1.64-1.58(4H), 1.30-1.25(12H), 0.96-0.83(6H)

<Synthesis Example 3 of Polymerizable Compounds>

Synthesis of 4-pentylcyclohexyl methacrylate (MACH-C5)

In a 4-necked flask, weigh 25.0 g (147 mmol) of 4-pentylcyclohexanol and 22.3 g (220 mmol) of triethylamine, add 400 mL of THF, and dissolve them completely at room temperature. After confirming the dissolution, keep the system at 0°C in an ice bath, and slowly add 18.4 g (176 mmol) of methacrylic acid chloride. After confirming the completion of the reaction by nuclear magnetic resonance spectroscopy ( ¹ H-NMR spectrum), add 100 mL of hexane to the reaction solution, wash it 3 times with 100 g of 10% sodium carbonate aqueous solution, and wash it 3 times with 100 mL of pure water, and dry it with anhydrous magnesium sulfate. After filtering and concentrating, vacuum drying is performed to obtain 20.3 g (86.2 mmol: yield 58.0%) of a transparent oily liquid. The structure was confirmed to be the target compound by ¹ H-NMR spectroscopy. The measurement data are shown below.

¹ H-NMR (400MHz, DMSO-d ₆ )δ: 6.15-5.95(1H), 5.65-5.60(1H), 4.95-4.90(0.60H), 4.65-4.57(0.40H), 1. 89-1.86(3H), 1.79-1.74(2H), 1.56-1.50(2H), 1.36-1.15(11H), 0.87-0.84(3H)

<Purchase of polymerizable compounds>

The polymerizable compound DMA was purchased directly from Tokyo Chemical Industry Co., Ltd. (TCI).

(Manufacturing of liquid crystal display components)

Using the AL-1~AL-7 obtained above, and the liquid crystal alignment agents SE-6414 and NRB-U438 (manufactured by Nissan Chemical Co., Ltd.) for horizontal alignment, liquid crystal cells were prepared, and liquid crystal display elements with the structure shown in Table 5 below were prepared.

The structure of the liquid crystal cell is shown in Table 5 below.

<First and second substrates>

The first and second substrates are alkali-free glass substrates with a size of 30mm×40mm and a thickness of 1.1mm. An ITO (Indium-Tin-Oxide) electrode with a thickness of 10μm is formed on the substrate. The first and second substrates are the same substrates, and the names are separated for convenience.

<Surface treatment steps of AL-1, AL-2, AL-3, SE-6414>

AL-1, AL-2, AL-3, and SE-6414 were filtered using a filter with an aperture of 1.0 μm, and then applied to the electrode forming surfaces of the first and second substrates using a spin coating method, and dried on a heating plate at 80°C for 2 minutes. Then, they were calcined in a thermal cycle heating furnace with an internal temperature of 230°C for 30 minutes to obtain a coating with a film thickness of 100 nm.

The first and second substrates with coatings obtained above were rubbed. After lamination, the rubbing directions were antiparallel. The first substrate was rubbed from the long side, and the second substrate was rubbed from the short side. As for the type of rubbing cloth, rayon cloth made by Yoshikawa Chemical was used: YA-20R, roller diameter 120mm.

The friction treatment of AL-1, AL-2, and AL-3 is carried out at a rotation speed of 500 rpm, a moving speed of 30 mm/sec, and a pushing amount of 0.3 mm.

In addition, the friction treatment of SE-6414 was carried out under the conditions of rotation speed 1000rpm, movement speed 20mm/sec, and push amount 0.4mm.

After the friction treatment, ultrasonic cleaning was performed in pure water for 1 minute and drying was performed at 80°C for 15 minutes.

<Surface treatment steps of AL-4, AL-5, AL-6, AL-7, and NRB-U438>

AL-5, AL-6, and AL-7 were filtered using a filter with an aperture of 1.0 μm, and then applied to the electrode forming surfaces of the first and second substrates using a spin coating method, and dried on a heating plate at 70°C for 90 seconds.

Thereafter, the film was exposed to linearly polarized light of wavelength 313 nm at 0.005 J/cm ² using a high-pressure mercury lamp (313 nm bandpass filter manufactured by CERMA PRECISION) and calcined on a heating plate at 150°C for 30 minutes.

AL-4 and NRB-U438 were filtered through a filter with an aperture of 1.0 μm, and then applied to the electrode-forming surfaces of the first and second substrates by spin coating, dried on a heating plate at 80°C for 2 minutes, and calcined in a heat cycle furnace with an internal temperature of 230°C for 30 minutes. Afterwards, a low-pressure mercury lamp (240nm or less short-wavelength cutoff filter manufactured by Ushio Electric Co., Ltd.) was used to expose the film with a wavelength of 254 nm of linear polarization at 0.3 J/cm ² , and calcined in a heat cycle furnace with an internal temperature of 230°C for 30 minutes.

<One exposure>

After the surface treatment step, the two substrates (first and second substrates) with liquid crystal alignment films were exposed to 10 J/cm ² of light with a wavelength of 313 nm using a high-pressure mercury lamp (short wavelength cutoff filter below 300 nm manufactured by CERMA PRECISION). When selective light irradiation is desired, a photomask (100, 50, 30, 5 μm L/S with chromium wiring manufactured by Mitani Micronics) was placed on the substrate to perform pattern exposure. This operation is then recorded as one exposure.

In addition, the single exposure is for the purpose of intentionally deactivating the radicals that generate free radicals contained in the alignment film, and is only applicable to Examples 23, 24, 27, 28, 29, 30, and 32.

<Production of Liquid Crystal Cells>

Using two substrates (first and second substrates) with liquid crystal alignment films after the surface treatment step is completed and the one-time exposure step is further performed for Examples 23, 24, 27, 28, 29, 30, and 32, the liquid crystal injection port is retained and the surroundings are sealed to produce an empty cell with a cell gap of about 4μm. In addition, the surface treatment step includes a rubbing treatment, and the empty cell is produced in a manner that the rubbing directions of the first substrate and the second substrate become anti-parallel.

In the empty cell, liquid crystal is injected into the empty cell at room temperature in vacuum (as shown in Table 4, each additive is added to the positive liquid crystal MLC-3019 for IPS manufactured by Merck or the negative liquid crystal MLC-7026 for IPS manufactured by Merck in a specified amount relative to the liquid crystal), and then the injection port is sealed to form a liquid crystal cell. The obtained liquid crystal cell constitutes an IPS mode liquid crystal display element. Afterwards, the obtained liquid crystal cell is heated at 120°C for 10 minutes.

<Double Exposure>

The prepared liquid crystal cell was irradiated with light of wavelength 313nm using a high-pressure mercury lamp (short-wavelength cutoff filter below 300nm manufactured by CERMA PRECISION). The irradiation amount is shown in Table 5. In addition, when selective light irradiation is desired, a mask (L/S of 100, 50, 30, 5μm with chromium wiring manufactured by Mitani Micronics) was placed on the liquid crystal cell to perform pattern exposure. Afterwards, this operation was recorded as secondary exposure. In addition, the secondary exposure is for the purpose of allowing the radicals contained in the alignment film to react with the polymerizable compound (additive) in the liquid crystal.

(Visual evaluation results of liquid crystal alignment after secondary exposure)

Use a polarizing plate configured as crossed nicols to confirm the alignment state of the liquid crystal cell after the second exposure. In addition, the angle between the uniaxial alignment direction of the liquid crystal and the polarization direction is set to 45 degrees. At this time, light is transmitted when the liquid crystal is uniaxially aligned, and light is not transmitted when it is out-of-plane aligned.

In the embodiment, cell 7 (embodiment 5) can be controlled in out-of-plane orientation, so the exposed area becomes a dark field (Figure 1A and Figure 1B).

FIG1A shows a photograph of a liquid crystal display element, and a schematic diagram of the photograph of the liquid crystal display element in FIG1A is shown in FIG1B (hereinafter, FIG2 to FIG5, and FIG9 are similar, the photograph of the liquid crystal display element is shown in FIGA, and the schematic diagram of the photograph is shown in FIGB).

In Figure 1 (Figure 1A and Figure 1B are collectively referred to as Figure 1), the exposed portion of symbol 1 represents the dark field (black), and the non-exposed portion of symbol 2 represents the bright field (white).

Cell 27 (Comparative Example 4) cannot perform out-of-plane alignment control, so the exposed area becomes a bright field (Figure 2A and Figure 2B).

In Figure 2 (Figure 2A and Figure 2B are collectively referred to as Figure 2), both the exposed area and the non-exposed area represent bright field (white).

Cell 1 (Example 1) is tilted (tilt) oriented (part of it is out-of-plane oriented), so the coloring of the exposed part is reduced (part of it is a dark field), showing a gray intermediate color (Figure 3A and Figure 3B).

In Figure 3 (Figure 3A and Figure 3B are collectively referred to as Figure 3), the exposed part of symbol 1 has a dark field (black) part b mixed with the intermediate color (gray) part a between light and dark. The non-exposed part of symbol 2 represents the bright field (white).

Using the same method as shown in Figures 1 to 3, the liquid crystal display elements in the embodiments and comparative examples shown in Tables 6 to 8 below are evaluated.

In Tables 6 to 8, the secondary exposure area represents a dark field (black) and can be controlled by out-of-plane alignment, marked as ○, represents a bright field (white) and cannot be controlled by out-of-plane alignment, marked as ×, and represents an intermediate color (gray) and has a uniaxial alignment with a tilt angle and uneven alignment, marked as △.

The visual evaluation results of the liquid crystal alignment after secondary exposure are shown in Table 6 below.

[Table 6]

In order to induce out-of-plane alignment from the in-plane uniaxial alignment state, it is necessary to (i) make the alignment film contain a radical-generating group, (ii) make the liquid crystal contain a polymerizable compound (additive), and (iii) irradiate with light. In addition, in order to form a good out-of-plane alignment state at this time, it is effective to consider the content of the radical-generating group, the content of the polymerizable compound, the amount of light irradiation, etc.

The visual evaluation results of the liquid crystal alignment after secondary exposure are shown in Table 7 below.

[Table 7]

The polymerizable compound (additive) required for out-of-plane alignment control is not limited to DMA. As long as it is an additive with an appropriate structure, out-of-plane alignment control can be performed. In addition, the type of liquid crystal is not limited to MLC-7026, which is a liquid crystal with a negative dielectric constant. Even MLC-3019, which is a liquid crystal with a positive dielectric constant, can also be used for out-of-plane alignment control.

The visual evaluation results of the liquid crystal alignment after secondary exposure are shown in Table 8 below.

When using a photo-alignment film that has been photo-aligned, out-of-plane alignment control can also be performed, which is independent of the type of polymer constituting the alignment film and the exposure wavelength required for photo-alignment. In addition, as shown in the liquid crystal cells 22, 23, etc. used in Examples 19, 20, etc., when using an alignment film material that does not have a base that generates free radicals, out-of-plane alignment control can be performed by mixing it with a polymer material that has a base that generates free radicals. At this time, as long as the base that generates free radicals is introduced in an appropriate amount, out-of-plane alignment control can be performed. In addition, when only the first substrate is coated with a photo-alignment film with free radical generating ability, as in Examples 21 and 22, out-of-plane alignment control can sometimes be performed. It depends on the type of photo-alignment film used. For example, when the alignment constraint of the liquid crystal is small, it will be observed when the alignment constraint of the liquid crystal is reduced due to light irradiation.

(Visual evaluation results of liquid crystal alignment during single exposure)

The polarizing plate configured as orthogonal Nicols was used to confirm the alignment state of the liquid crystal cell after the second exposure. In addition, the angle between the uniaxial alignment direction of the liquid crystal cell and the polarization direction was set to 45 degrees. The results are shown in Table 9 below.

In terms of one exposure, if only the entire surface of the first substrate is exposed, a tilted alignment is formed (Figure 4A and Figure 4B).

In FIG. 4 (FIG. 4A and FIG. 4B are collectively referred to as FIG. 4), the portion indicated by symbol 3 is an area where only the first substrate is exposed by one exposure and the entire surface is exposed by two exposures. The portion indicated by symbol 3 represents a gray intermediate color, forming a tilt alignment. The portion indicated by symbol 4 is a non-exposed area where only the first substrate is exposed by one exposure and not exposed by two exposures. The portion indicated by symbol 4 represents a bright field (white), forming an in-plane alignment.

If the first substrate and the second substrate are fully exposed in one exposure, an in-plane alignment is formed (Figure 5A and Figure 5B).

In FIG. 5 (FIG. 5A and FIG. 5B are also collectively referred to as FIG. 5), the portion indicated by symbol 5 is an area where the first and second substrates are exposed by a single exposure and the entire surface is exposed by a double exposure. The portion indicated by symbol 6 is an area where the first and second substrates are exposed by a single exposure and the non-exposed area is not exposed by a double exposure. The portions indicated by symbols 5 and 6 both represent a bright field (white), forming an in-plane alignment. This confirms that by irradiating the substrate before the cell is made with light, the radicals contained in the alignment film that generate free radicals are inactivated, and no reaction with the polymerizable compound (additive) is induced during the double exposure, and no out-of-plane alignment is formed.

(Evaluation of alignment patterning)

The alignment state of the liquid crystal display element exposed by the pattern was confirmed using a polarizing plate configured as orthogonal Nicols. In addition, the angle between the uniaxial alignment direction of the liquid crystal cell and the polarization direction was set to 45 degrees. The evaluation of the alignment pattern was visually observed and judged from the perspective of whether the alignment could be controlled by light irradiation, the uniformity of the alignment, and the brightness of the alignment control surface (the interface between the in-plane uniaxial alignment and the out-of-plane alignment). The results are shown in Table 10 below.

The change in orientation from in-plane (uniaxial) orientation to out-of-plane orientation due to light irradiation can be uniformly controlled, and the interface between different orientations is distinct (Figure 6). As shown in Figure 6, it can be confirmed that the in-plane orientation area in the bright field (white) and the out-of-plane orientation area in the dark field (black) can be clearly patterned.

In addition, this does not depend on the type of polymer constituting the alignment film or the alignment treatment method. The alignment pattern can be made using significantly different types of materials, so it can be inferred that the embodiments in Tables 6 to 8 that can perform out-of-plane alignment control can all be patterned.

(Evaluation of fine alignment patterning)

The alignment state of the patterned liquid crystal display element was confirmed using a polarizing plate configured as orthogonal Nicols. In addition, the angle between the uniaxial alignment direction of the liquid crystal cell and the polarization direction was set to 45 degrees. The evaluation of alignment patterning was performed by visual observation and judgment from the perspective of whether the alignment could be controlled by light irradiation, the uniformity of the alignment, and the brightness of the alignment control surface (the interface between the in-plane uniaxial alignment and the out-of-plane alignment). The results are shown in Table 11 below.

For a single exposure, a liquid crystal display element made using a substrate exposed with a pattern can produce a uniform and clear fine alignment pattern regardless of the L/S width of the mask.

For example, a photograph of the liquid crystal display element obtained in Example 27 is shown in FIG7. At this time, only the first substrate is exposed to pattern exposure in one exposure, so the middle color (gray) portion represented by symbol 7 in FIG7 forms a tilted alignment state. The dark field (black) portion represented by symbol 8 in FIG7 forms an out-of-plane alignment state.

FIG8 shows the result of Example 30 obtained by changing the L/S width of the mask of Example 27. In FIG8, the difference between the intermediate color (gray) part and the dark field (black) part is as shown in FIG7.

In addition, if you want to make the middle color (gray) part become a uniaxial alignment in the plane, the second substrate is also exposed with the same pattern as the first substrate, and the exposed parts are bonded to each other to make a liquid crystal cell, and then a second exposure is performed.

For a liquid crystal display element that performs pattern exposure in a double exposure instead of a single exposure, as shown in Example 31, it can be confirmed that alignment patterning can be performed under the condition that the L/S width of the mask is 100μm. In the liquid crystal display element of Example 31, the in-plane alignment area of the bright field (white) and the out-of-plane alignment area of the dark field (black) can also be clearly patterned.

In addition, as shown in Example 32, it can be confirmed that by exposing the first and second substrates in a pattern, laminating the patterns vertically to produce a liquid crystal cell, and then performing a second exposure, three alignment states of in-plane uniaxial alignment, out-of-plane alignment, and tilted alignment can be produced in one liquid crystal display element.

The results of the liquid crystal display element obtained in Example 32 are shown (FIG. 9A and FIG. 9B). FIG. 9A shows a photograph of the liquid crystal display element, and a schematic diagram of the photograph of the liquid crystal display element of FIG. 9A is shown in FIG. 9B.

As shown in FIG9 (FIG9A and FIG9B are collectively referred to as FIG9), the dark field (black) portion represented by symbol 9 forms an out-of-plane alignment state. The bright field (white) portion represented by symbol 10 forms an in-plane alignment. The intermediate color (gray) portion represented by symbol 11 (in FIG9B, the portion represented by the diagonal line pattern) forms a tilt alignment state.

[Industrial applicability]

According to the present invention, a liquid crystal display element having at least two patterned regions among an in-plane alignment region, an out-of-plane alignment region, and a tilted alignment region can be manufactured industrially with good productivity.

Claims (11)

A method for manufacturing a liquid crystal display element, characterized by comprising: step (A): forming a free radical generating film on one substrate that can generate free radicals by light irradiation, and forming a free radical generating film on another substrate that can generate free radicals by light irradiation; and step (B): making a liquid crystal composition containing liquid crystal and a free radical polymerizable compound contact the free radical generating film, while maintaining the state, irradiating the liquid crystal composition with light having a peak at 240-400nm that is sufficient to cause the free radical polymerizable compound to undergo a polymerization reaction; the one substrate and the other substrate form a pair of substrates; the free radical polymerizable compound has the effect of causing the liquid crystal to align vertically by polymerizing. function; the free radical generating film formed on the one substrate and the free radical generating film formed on the other substrate are films treated with uniaxial alignment and have the function of forming in-plane alignment; for at least one of the pair of substrates, the step of the following element (Z1) is further included, in which when the free radical generating film is irradiated with light, the step (a) is included in the case of pattern exposure, and the step (b) is included in the case of full-surface exposure, and a combination of (i) a tilted alignment region and an in-plane alignment region, (ii) a tilted alignment region and an out-of-plane alignment region, and (iii) a tilted alignment region, an in-plane alignment region, and an out-of-plane alignment region is manufactured A liquid crystal display element having at least two different types of regions patterned by a combination of any one of the combinations of; the tilted alignment region is a region formed by arranging the one substrate aligned in-plane and the other substrate aligned out-of-plane in the pair of substrates in such a manner that they face each other, or arranging the one substrate aligned out-of-plane and the other substrate aligned in-plane in such a manner that they face each other; the in-plane alignment region is a region formed by arranging the one substrate aligned in-plane and the other substrate aligned in-plane in the pair of substrates in such a manner that they face each other; the out-of-plane alignment region is a region formed by arranging the one substrate aligned out-of-plane and the other substrate aligned out-of-plane in the pair of substrates in such a manner that they face each other; Item (Z1): There is a step (C) between the step (A) and the step (B), which is to irradiate the free radical generating film obtained in the step (A) with light having a peak at 240-400nm to inactivate the free radical generating ability of the free radical generating film; step (a): by exposing the pattern, a portion where the free radical generating ability of the free radical generating film is inactivated and a portion where the free radical generating ability of the free radical generating film is not inactivated are formed; step (b): in the case where the free radical generating ability of the free radical generating film is inactivated by the whole surface exposure, further comprising the following element (Z2); element (Z2): the step of irradiating the liquid crystal composition with light having a peak at 240-400nm in the step (B) is performed through a photomask. The manufacturing method of the liquid crystal display element as claimed in claim 1, wherein the step (B) of irradiating the liquid crystal composition with light having a peak at 240-400nm is performed in the absence of an electric field. A method for manufacturing a liquid crystal display element as claimed in claim 1 or 2, wherein at least one of the free radical generating film formed on the one substrate and the free radical generating film formed on the other substrate has a polymer containing an organic group that induces free radical polymerization. The method for manufacturing a liquid crystal display device according to claim 3, wherein the polymer containing an organic group that induces free radical polymerization has a structural unit represented by the following formula (1) in the main chain;

In formula (1), A represents an organic group that induces free radical polymerization. A method for manufacturing a liquid crystal display element as claimed in claim 3, wherein the polymer is selected from at least one of 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. A method for manufacturing a liquid crystal display device as claimed in claim 4, wherein the organic group inducing free radical polymerization is a group represented by the following formula (3); ---- ^R6 - ^R7 - ^R8 ( ₃ ) In formula (3), the dotted line represents a bond with a benzene ring, ^R6 represents a single bond, _-CH2- , -O-, -COO-, -OCO-, _-NHCO- , -CONH-, -NH-, -CH2O-, -N(CH3)-, -CON( _CH3 )-, or -N( _CH3 )CO-; ^R7 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 -One or more of them may be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic group. In addition, 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; ^R8 represents an organic group that induces free radical polymerization and is selected from the group represented by the formula [X-1] to [X-18], [W], [Y], and [Z];

In formulas [X-1] to [X-18], * represents a bonding site with ^R7 , _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;

In formulas [W], [Y], and [Z], * represents a bonding site with R ⁷ , S ³ represents a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH 3 )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-, 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 are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group, a benzyl group, or a phenethyl group, and when they are an alkyl group or an alkoxy group, R ⁹ and R ¹⁰ may form a ring; Q represents any of the following structures;

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 an atomic bond; 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 method for manufacturing a liquid crystal display device according to claim 5, wherein the diamine containing an organic group inducing free radical polymerization is a diamine represented by the following formula (2);

In formula (2), ^A1 and ^A2 each independently represent a hydrogen atom or a group represented by the following formula (3), provided that at least one of ^A1 and ^A2 represents a group represented by the following formula ( ₃ ), E represents a single bond, -O-, -C(CH3) _2- , -NH-, -CO-, -NHCO-, -COO-, -( _CH2 ) _m- , _-SO2- , or a divalent organic group composed of any combination thereof, m represents an integer of 1 to 8; p represents an integer of 0 to 2; when p is 2, a plurality of ^A2 and E each independently have the above definition; and when p is 0, ^A1 is composed of a group represented by the following formula (3); ^-R6 - ^R7 - ^R8 (3) In formula (3), a dotted line represents a bond to a benzene ring, ^R6 represents a single bond, _-CH2 -, -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 - of the alkylene group may be independently replaced by a group selected from -CH= _CH- , a divalent carbon ring, and a divalent heterocyclic group, and may also be replaced by any of the following groups, i.e., -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH-, provided that they are not adjacent to each other; R ⁸ represents an organic group inducing free radical polymerization selected from the group consisting of formulae [X-1] to [X-18], [W], [Y] and [Z];

In formulas [X-1] to [X-18], * represents a bonding site with ^R7 , _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;

In formulas [W], [Y], and [Z], * represents a bonding site with R ⁷ , S ³ represents a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH 3 )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-, 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 are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group, a benzyl group, or a phenethyl group, and when they are an alkyl group or an alkoxy group, R ⁹ and R ¹⁰ may form a ring; Q represents any of the following structures;

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 an atomic bond; 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 liquid crystal display element as claimed in claim 1 or 2, wherein at least one of the free radical polymerizable compounds is a compound having a polymerizable unsaturated bond in one molecule and being compatible with liquid crystal. The method for manufacturing a liquid crystal display device as claimed in claim 8, wherein the polymerization reactive group of the free radical polymerizable compound is selected from the following structures;

In the formula, * represents a bonding site other than a polymerizable unsaturated bond with a compound molecule; ^Rb represents an alkyl group having 3 to 20 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; and the alkyl group of ^Rb represents a linear, branched, or cyclic alkyl group. A method for manufacturing a liquid crystal display element as claimed in claim 1 or 2, 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 display element as claimed in claim 1, wherein the substrate is a substrate having a comb-tooth electrode.