KR20190076037A - Liquid crystal device, manufacturing method thereof, display device, and liquid crystal alignment agent - Google Patents

Abstract

A liquid crystal device includes a pair of substrates arranged to face each other, a pair of transparent electrodes arranged on mutually facing surfaces of the pair of substrates, a liquid crystal composition disposed between the pair of substrates and including liquid crystal and a polymerizable compound And a liquid crystal alignment film formed on at least one of the electrode arrangement surfaces of the pair of substrates. The liquid crystal composition contains at least one member selected from the group consisting of a monofunctional (meth) acrylate compound, a polyfunctional (meth) acrylate compound, a polyfunctional thiol compound and a styrene compound as a polymerizable compound. The liquid crystal alignment film is formed by a liquid crystal aligning agent containing poly (meth) acrylate.

Description

Liquid crystal device, manufacturing method thereof, and display device

[Cross reference of related application]

The present application is based on Japanese Patent Application No. 2017-10532 filed on January 24, 2017, the content of which is incorporated herein by reference.

This disclosure relates to a liquid crystal device, a manufacturing method thereof, and a display device.

As a liquid crystal device, there has recently been known a polymer dispersed liquid crystal device in which a liquid crystal layer composed of a composite material of a liquid crystal and a polymer is disposed between a pair of film substrates on which transparent electrodes are formed on the surface. Type liquid crystal device as a light modulating element (see, for example, Patent Document 1 or Patent Document 2). In the light control element of Patent Documents 1 and 2, the transparency is changed by switching the voltage application / voltage unapplication of the transparent electrode to manifest the dimming function. In addition, it has been studied to give new functions to a show window, a smart phone, a television, a monitor, a building, furniture, and the like by using such a dimming function. As the polymer dispersed liquid crystal, for example, PDLC (Polymer Dispersed Liquid Crystal) and PNLC (Polymer Network Liquid Crystal) are known.

Patent Document 3 proposes a display device in which a liquid crystal display panel is arranged on the back surface of a transparent display made of organic EL elements. In this display device, it has been proposed to control the light transmittance by controlling the voltage applied to the liquid crystal display panel, thereby enhancing the visibility of the display of the transparent display. Patent Document 4 discloses a reverse type liquid crystal device in which light is transmitted and becomes transparent when a voltage is not applied between a pair of electrodes, and light is scattered and becomes non-transparent when a voltage is applied . The reverse type liquid crystal device described in Patent Document 4 has a polyimide film as an alignment film for vertically aligning the liquid crystal, and the alignment state of the liquid crystal molecules in the liquid crystal layer is controlled by the polyimide film.

Japanese Laid-Open Patent Publication No. 2013-3319 Japanese Laid-Open Patent Publication No. 2013-148744 Japanese Laid-Open Patent Publication No. 2008-083510 International Publication No. 2015/022980

In the design of an alignment film material in a liquid crystal display panel such as a liquid crystal TV, a polyimide-based material has been conventionally used effectively from the viewpoint of securing properties such as liquid crystal alignability and electric characteristics. On the other hand, in the liquid crystal display panel and the light control element, various priorities of various characteristics required for the liquid crystal alignment film are different. For example, when it is used as a light control device, it is required to have a thinner liquid crystal device and better shape diversity than properties relating to display quality, such as liquid crystal alignability and electrical characteristics.

One of the methods for improving the thinness and the variety of shapes of the liquid crystal device is to thin the substrate and to broaden the selection of the material. For example, a substrate made of a polymer material is considered to be applied. Further, in order to be able to apply a substrate made of a polymer material, a polymer used as an alignment film material is required to have excellent solubility in a low boiling point solvent. However, it is feared that a polyimide-based resin is generally hardly soluble in a low-boiling solvent and that a uniform liquid crystal alignment film can not be obtained due to uneven film thickness, unevenness in coating, and pinholes in the obtained coating film.

Further, a liquid crystal alignment film using a polyimide-based resin tends to be colored, and when applied to a light control device, transparency in a light transmitting state becomes a problem in some cases. Further, since the light control device is assumed to be used for outdoor use, it may be necessary to have excellent weather resistance.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and it is an object of the present invention to provide a liquid crystal alignment film which is homogeneous and has high transparency, good light transmission property and light scattering property, And which is excellent in weather resistance. The present invention also provides a liquid crystal device comprising:

In order to solve the above-described problems, the present disclosure adopts the following means.

[1] A liquid crystal display device comprising: a pair of substrates arranged opposite to each other; electrodes arranged on surfaces of the pair of substrates facing each other; and a liquid crystal composition disposed between the pair of substrates, And a liquid crystal alignment layer formed on at least one of the pair of substrates, wherein the liquid crystal alignment layer is formed by curing the liquid crystal composition, wherein the liquid crystal composition contains a monofunctional (meth) acrylate compound, a polyfunctional (Meth) acrylate compound, a polyfunctional thiol compound, and a styrene compound, wherein the liquid crystal alignment film is formed by a liquid crystal aligning agent containing poly (meth) acrylate, Liquid crystal device.

[2] A display device comprising the liquid crystal element of [1] above, and a transparent display which becomes transparent in a non-display state.

[3] A liquid crystal device for forming a liquid crystal alignment film of a liquid crystal device having a liquid crystal layer formed by curing a liquid crystal composition containing a liquid crystal and a polymerizable compound between a pair of substrates arranged so that electrodes formed on respective substrate surfaces face each other As the alignment agent, a liquid crystal aligning agent containing poly (meth) acrylate.

[4] A method for manufacturing a liquid crystal device comprising a liquid crystal layer formed by curing a liquid crystal composition comprising a liquid crystal and a polymerizable compound between a pair of substrates arranged so that electrodes formed on respective substrate surfaces face each other, A step of forming a liquid crystal alignment layer by applying a liquid crystal aligning agent on at least one electrode arrangement surface of the substrate of the liquid crystal alignment layer; And a step of curing the polymerizable compound after the formation of the liquid crystal cell, wherein the liquid crystal composition contains, as the polymerizable compound, a monofunctional (meth) acrylate compound, At least one member selected from the group consisting of a polyfunctional (meth) acrylate compound, a polyfunctional thiol compound and a styrene- And the liquid crystal aligning agent contains poly (meth) acrylate.

According to the above configuration, even when a base material made of a polymer material is used as a pair of substrates, a liquid crystal device having a liquid crystal alignment film that is homogeneous and has high transparency can be obtained. In addition, even when a base material made of a polymer material is applied, a liquid crystal device exhibiting good light transmission properties and light scattering properties, exhibiting sufficient electric characteristics for realizing a dimming function, and excellent weather resistance can be obtained.

1 is a diagram showing a schematic configuration of a liquid crystal element.
2 is a view for explaining the function of the liquid crystal element.
3 is a view showing a schematic configuration of a display device including a liquid crystal element and a transparent display.

(Mode for carrying out the invention)

Hereinafter, embodiments will be described with reference to the drawings.

<Liquid Crystal Device>

As shown in Fig. 1, the liquid crystal element 10 of the present embodiment includes a pair of substrates composed of a first substrate 11 and a second substrate 12, a first substrate 11, And a liquid crystal layer 13 disposed between the liquid crystal layer 12 and the liquid crystal layer 13. The liquid crystal layer 13 is a polymer dispersed liquid crystal layer which is a polymer / liquid crystal composite layer in which a polymer 13a and liquid crystal molecules 13b are mixed. In this embodiment, a polymer dispersed liquid crystal PDLC). The liquid crystal element 10 is a light control element that switches the transmission state through which light passes and the non-transmission state where light is scattered by controlling the orientation of the liquid crystal molecules 13b existing in the polymer network by an electric field.

The first base material (11) and the second base material (12) are transparent materials made of a polymer material. Examples of the polymer material constituting the base material include silicon, polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate, polypropylene, polyvinyl chloride, aromatic polyamide, polyamideimide, polyimide, Acetyl cellulose (TAC), polymethyl methacrylate, and the like. Although the first substrate 11 and the second substrate 12 may be glass substrates, a plastic substrate is particularly preferable in order to reduce the thickness and weight of the liquid crystal device.

In the first base material and the second base material 12, transparent electrodes 16 and 17 are arranged on the surfaces facing each other, and electrode pairs are formed by the transparent electrodes 16 and 17. In this embodiment, the transparent electrodes 16 and 17 is a transparent conductive film is, for example, tin oxide (SnO ₂₎ as made NESA film (US PPG Company registered trademark), indium oxide-tin (In ₂ O ₃ oxide -SnO ₂ ), or a film made of a carbon material. The transparent electrodes 16 and 17 may have a predetermined pattern such as a comb-like shape.

Liquid crystal alignment films 14 and 15 are formed on the electrode placement surfaces of the first base 11 and the second base 12, respectively. The liquid crystal alignment layers 14 and 15 are organic thin films which regulate the alignment direction of liquid crystal molecules in the liquid crystal layer 13 and in this embodiment are formed by using a polymer composition comprising a polymer having photo- to be. The liquid crystal alignment films 14 and 15 may be formed on at least one of the pair of substrates, but they are preferably formed on both substrates from the standpoint of alignment stability. The liquid crystal layer 13 is formed by arranging a liquid crystal composition in a space surrounded by a pair of substrates and a sealant (not shown) arranged between the pair of substrates so as to surround the outer edge of the electrode placement surface, . The liquid crystal composition contains a liquid crystal and a polymerizable compound.

The liquid crystal element 10 does not have a polarizing plate on the outer surfaces of the first base 11 and the second base 12. Therefore, it is excellent in that the absorption loss of light is small and the utilization efficiency of light is high.

(A) shows a state in which no voltage is applied between the transparent electrodes 16 and 17, (b) shows a state in which no voltage is applied to the transparent electrodes 16 and 17 ) In a state where the voltage is applied. The liquid crystal element 10 is a reverse type PDLC. In a state in which no voltage is applied between the transparent electrodes 16 and 17, incident light is transmitted from one side of the pair of substrates to the other side to be in a transparent state, 16, and 17, the alignment state of the liquid crystal molecules 13b changes, so that the incident light is scattered to become a non-transparent state. In the present embodiment, as shown in Fig. 2, in the voltage unapplied state, the longitudinal direction of the liquid crystal molecules 13b is perpendicular to the substrate surface, so that the liquid crystal element 10 is in a transparent state, , And the liquid crystal molecules 13b are rotated in a direction parallel to the substrate surface, whereby the liquid crystal element 10 becomes a non-transparent state. By switching the application / non-application of such a voltage, the liquid crystal element 10 emits a dimming function. The liquid crystal element 10 is, for example, film-like or plate-like. Further, the liquid crystal element 10 may have a variable light transmittance in accordance with an applied voltage.

&Lt; Liquid crystal composition &

Next, the liquid crystal composition used for forming the liquid crystal layer 13 will be described. The liquid crystal composition contains a liquid crystal and a polymerizable compound. Examples of the liquid crystal include nematic liquid crystal and smectic liquid crystal.

The polymerizable compound is preferably a compound exhibiting radical polymerizability and is preferably at least one compound selected from the group consisting of a monofunctional (meth) acrylate compound, a polyfunctional (meth) acrylate compound, a polyfunctional thiol compound, It is particularly preferable to include one kind of compound (hereinafter also referred to as &quot; specific polymerizable compound &quot;). In the present specification, "(meth) acrylate" means acrylate and methacrylate.

Specific examples of the polymerizable compound include monofunctional (meth) acrylate compounds such as (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, (Meth) acrylates such as n-hexyl (meth) acrylate and 2-ethylhexyl (meth) acrylate; Cycloalkyl (meth) acrylates such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate; Aryl (meth) acrylates such as benzyl (meth) acrylate;

(Meth) acrylate, 2-methoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, phenoxyethyl Acrylate, methoxytriethylene glycol (meth) acrylate, ethoxylated o-phenylphenol (meth) acrylate, ethyldiethylene glycol (meth) acrylate, glycidyl (meth) acrylate, tetrahydrofurfuryl Ether (meth) acrylates such as methyl (meth) acrylate;

Alcohol-based (meth) acrylates such as 2-hydroxyethyl (meth) acrylate; Carbonic acid type (meth) acrylates such as 2- (meth) acryloyloxyethyl succinic acid and 2- (meth) acryloyloxyethylhexahydrophthalic acid; Nitrogen-containing unsaturated compounds such as acrylamide, (meth) acryloylmorpholine, isobutoxymethyl (meth) acrylamide, vinylcaprolactam and N-vinyl-2-pyrrolidone; Halogenated (meth) acrylates such as tetrabromophenyl (meth) acrylate and pentachlorophenyl (meth) acrylate; 3- (meth) acryloxypropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and the like;

Examples of the polyfunctional (meth) acrylate compound include ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,6- (Meth) acrylate, neopentyl glycol di (meth) acrylate, (meth) acryloyloxypivalyl (meth) acryloyloxy pivalate, 2-hydroxy- (Meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,9-nonanediol di Acrylate, pentaerythritol tetra (meth) acrylate, trimethylol propane (meth) acrylate, ethoxylated trimethylol propane tri (meth) acrylate, di (Meth) acrylate compounds such as trimethylolpropane tetra (meth) acrylate, urethane (meth) acrylate compounds such as phenylglycidyl ether (meth) acrylate hexamethylene diisocyanate urethane prepolymer, pentaerythritol tri Methylene diisocyanate urethane prepolymer, dipentaerythritol penta (meth) acrylate hexamethylene diisocyanate);

Examples of the polyfunctional thiol compound include 1,3-propanedithiol, 1,4-butanedithiol, 1,6-hexanedithiol, 2,5-hexanedithiol, (3-mercaptobutyryloxy) butane, tetraethylene glycol bis (3-mercaptopropionate, Di (mercaptomethyl) benzene, 1,3-di (mercaptomethyl) benzene, 1,3-di 4-thiadiazole, 1,4-bis (2-mercaptoethyl) benzene, ester of a thiol group-containing carboxylic acid with a dihydric alcohol Dithiol compounds such as Liu;

Isocyanuric acid, trimercaptobenzene, 2,4,6-trimercapto-1,3,5-triazine, 1,3,5-tris (3-mercaptobutyryloxyethyl) -1,3 Trimethylolpropane tris (3-mercapto-propionate), trimethylolpropane tris (3-mercaptopropionate), tris (3-mercaptopropionyloxy) -ethyl] -isocyanurate, trimethylol ethane tris (3-mercaptobutyrate), pentaerythritol tetrakis (3-mercaptobutyrate), pentaerythritol tetrakis (E.g., 3-mercaptopropionate), dipentaerythritol hexakis (3-mercaptopropionate), a polyfunctional polymer having a thiol group (for example, Registered trademark) (trade name, manufactured by Toray Fine Chemicals Co., Ltd.)), polythiol compounds such as polyesters of a thiol group-containing carboxylic acid and a polyhydric alcohol, and the like;

Examples of the styrene compound include styrene and methylstyrene.

One kind of polymerizable compound may be used alone, but two or more kinds of polymerizable compounds are preferably used in combination from the viewpoint of improving optical characteristics. Specifically, the liquid crystal composition preferably contains a monofunctional (meth) acrylate compound and a polyfunctional (meth) acrylate compound as the polymerizable compound, and the monofunctional (meth) acrylate compound, the polyfunctional Acrylate compound and a polyfunctional thiol compound. It is particularly preferable that a urethane (meth) acrylate compound is contained as at least a part of the monofunctional (meth) acrylate compound and the polyfunctional (meth) acrylate compound.

The content of the polymerizable compound in the liquid crystal composition is appropriately selected depending on the kind of the compound. For example, the content of the monofunctional (meth) acrylate compound is preferably 10 to 300 parts by mass, more preferably 20 to 200 parts by mass, per 100 parts by mass of the total amount of the liquid crystals. The content of the polyfunctional (meth) acrylate compound is preferably 1 to 200 parts by mass, more preferably 5 to 100 parts by mass, per 100 parts by mass of the total amount of the liquid crystals.

When a urethane (meth) acrylate compound is contained, the content of the urethane (meth) acrylate compound is preferably 1 to 150 parts by mass, more preferably 5 to 100 parts by mass, per 100 parts by mass of the total amount of the liquid crystals.

The content of the polyfunctional thiol compound is preferably 0.5 to 50 parts by mass, more preferably 1 to 40 parts by mass, per 100 parts by mass of the total amount of the liquid crystals. The compounding ratio of the styrene compound is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 20 parts by mass, per 100 parts by mass of the total amount of the liquid crystals.

The content of the polymerizable compound in the liquid crystal composition (the total amount thereof if two or more are included) is preferably from 1 to 90% by mass, more preferably from 5 to 80% by mass based on the total amount of the liquid crystal and the polymerizable compound, , More preferably from 10 to 75% by mass.

The proportion of the specific polymerizable compound is preferably 70% by mass or more, more preferably 80% by mass or more, and 90% by mass or more, based on the total amount of the polymerizable compounds to be contained in the liquid crystal composition More preferable. The polymerizable compound to be contained in the liquid crystal composition is particularly preferably composed of a specific polymerizable compound.

The liquid crystal composition may contain other components besides the liquid crystal and the polymerizable compound. From the viewpoint of further increasing the polymerizability of the polymerizable compound and promoting the formation of the polymer network (preferably, throughout the liquid crystal layer 13) in the liquid crystal layer 13, a polymerization initiator .

The polymerization initiator contained in the liquid crystal composition is preferably a compound (photo initiator) capable of initiating polymerization of the polymerizable compound by irradiation with radiation such as visible light, ultraviolet light, ultraviolet light, electron beam, X-ray or the like. The photoinitiator is preferably a radical polymerization initiator capable of generating a radical by light irradiation. Specific examples thereof include acetophenone, benzophenone, 2-benzoylbenzoic acid, 4,4'-bis (diethylamino) benzo 2-phenylacetophenone, 2- (1,3-benzodioxol-5-yl) -4,6-bis (trichloromethyl) Methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propanone, acetophenone benzyl ketal, 1-hydroxycyclohexyl phenyl ketone , 2,2-dimethoxy-2-phenylacetophenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone , 4,4'-diaminobenzophenone, benzyldimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 2,2-dimethoxy- Diphenylethan-1-one, 2-isopropylthioxanthone, 2-chloro (2,4,6-trimethoxybenzoyl) phosphine oxide, bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, 2-hydroxy- Benzyl-2-methylpropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholyl) (Phenylthio) -, 2- (O-benzoyloxime) -butanone-1,2,4,6-trimethylbenzoyl-diphenylphosphine oxide, ], Ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol- , 2-hydroxy-2-phenylacetophenone, 4,4'-dimethoxybenzyl, diphenylethanedione, 2-benzyl- 2- (dimethylamino) -1- [4- (morpholino) 1-butanone, and the like.

The content of the polymerization initiator in the liquid crystal composition is preferably from 0.1 to 10 parts by weight based on 100 parts by weight of the component (solid content) other than the solvent contained in the liquid crystal composition, from the viewpoints of accelerating the curing reaction and suppressing the lowering of the curability, Is preferably 0.1 to 10 mass%, more preferably 0.5 to 8 mass%, and even more preferably 1 to 7 mass%. The polymerization initiator may be used alone or in combination of two or more.

As other components to be blended in the liquid crystal composition, a dye may be used. By using the dye, the liquid crystal element 10 in which the dye is dispersed in the liquid crystal layer 13 can be obtained. Further, according to the liquid crystal element 10 of the present disclosure, even when the coloring matter is dispersed in the liquid crystal layer 13, it is clear that the change of the light shielding property / light transmittance by switching the application / Durability in the case of driving is also preferable.

As the coloring matter, a dichromatic coloring matter can be preferably used. The dichroic dye to be used is not particularly limited, and a known compound can be appropriately used. Examples thereof include a poly iodide, an azo compound, an anthraquinone compound, and a dioxazine compound. Of these, at least one member selected from the group consisting of an azo compound and an anthraquinone compound is preferable, and an azo compound is particularly preferable because of excellent light resistance and high two-color ratio. The coloring matters may be used singly or in combination of two or more kinds.

The blending ratio of the coloring matter (when two or more kinds are blended, the total amount thereof) is preferably 0.05 to 5% by mass, more preferably 0.1 to 3% by mass with respect to the total mass of the solid components in the liquid crystal composition .

The liquid crystal composition is prepared by mixing a liquid crystal and a polymerizable compound, and other components added as required. The treatment for mixing these components may be performed at room temperature or while the temperature is raised. It is also possible to dissolve each component in a suitable organic solvent, and then remove the solvent by, for example, distillation.

<Liquid Crystal Aligner>

Next, the liquid crystal aligning agent used for forming the liquid crystal alignment films 14 and 15 will be described. The liquid crystal aligning agent contains poly (meth) acrylate as a polymer component. In the present specification, "poly (meth) acrylate" means polyacrylate and polymethacrylate.

(Poly (meth) acrylate)

The poly (meth) acrylate is, for example, a method of reacting a monomer having a (meth) acryloyl group (hereinafter also referred to as a "(meth) acrylic monomer") in the presence of a polymerization initiator. The poly (meth) acrylate used in the preparation of the liquid crystal aligning agent is preferably such that the ratio of the (meth) acrylic monomer to the total amount of the monomers used in the polymerization is preferably 20% by mass or more, more preferably 30 Mass% or more, more preferably 40 mass% or more, and particularly preferably 50 mass% or more.

The (meth) acrylic monomer to be used in the polymerization is not particularly limited, and examples thereof include unsaturated carboxylic acids such as (meth) acrylic acid,? -Ethylacrylic acid, maleic acid, fumaric acid, itaconic acid and vinylbenzoic acid, (Meth) acrylate, tricyclo [5.2.1.0 ^2,6 ] deca-8- (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, (Meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, trimethoxysilylpropyl (meth) acrylate, 2,2 , 2-trifluoroethyl, 2,2,3,3,3-pentafluoropropyl (meth) acrylate, methoxyethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) ) Methoxypolyethylene glycol acrylate, (meth) acrylic acid tetrahydrofur Acrylate, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, 3,4-epoxybutyl Unsaturated carboxylic acid anhydrides such as maleic anhydride, itaconic anhydride and cis-1,2,3,4-tetrahydrophthalic anhydride; and the like. These (meth) acrylic monomers may be used alone or in combination of two or more.

The (meth) acrylic monomer used in the polymerization contains a (meth) acrylic monomer having an epoxy group from the viewpoint of improving the liquid crystal alignability and electrical properties of the obtained liquid crystal device 10 and the adhesion of the liquid crystal alignment film to the substrate . The proportion of the (meth) acrylic monomer having an epoxy group is preferably 1% by mass or more, more preferably 5% by mass or more, and more preferably 10% by mass or more based on the total amount of the monomers used in the polymerization Is more preferable.

Further, in the polymerization, other monomers other than the (meth) acrylic monomer may be used. Examples of other monomers include conjugated diene compounds such as 1,3-butadiene and 2-methyl-1,3-butadiene; Aromatic vinyl compounds such as styrene, methylstyrene and divinylbenzene; Maleimide group-containing compounds, and the like. The proportion of the other monomer is preferably 80 mass% or less, more preferably 70 mass% or less, and most preferably 60 mass% or less, relative to the total amount of the monomers used in the synthesis of the poly (meth) .

The poly (meth) acrylate contained in the liquid crystal aligning agent preferably does not have a side chain structure (hereinafter also referred to as "specific side chain structure") contained in the group consisting of the following (a) to (e) .

(a) an alkyl group having from 8 to 22 carbon atoms

(b) a fluorine-containing alkyl group having 6 to 18 carbon atoms

(c) a group in which a ring of any one of a benzene ring, a cyclohexane ring, and a heterocyclic ring and an alkyl group having 1 to 20 carbon atoms or a fluorine-containing alkyl group

(d) a group having at least two rings in total of at least one ring selected from the group consisting of a benzene ring, a cyclohexane ring and a heterocycle

(e) a group of 17 to 51 carbon atoms having a steroid skeleton

Specific examples of the specific branched structure include (a) an alkyl group such as an n-octyl group, an n-nonyl group, a n-decyl group, a n-dodecyl group, -Heptadecyl group, n-octadecyl group and the like; As the fluorine-containing alkyl group of (b), for example, a group in which at least one hydrogen atom of the alkyl group in (a) is substituted with a fluorine atom; (c) and the group (d) include, for example, groups represented by the following formula (5); (e) include, for example, a cholestanyl group, a cholestearyl group, a lanostanyl group and the like.

(In the formula (5), A ^{1 to} A ³ each independently represents a phenylene group or a cyclohexylene group, and may have a substituent at the ring part, and R ²¹ represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, An alkoxy group having 1 to 20 carbon atoms, a fluorine-containing alkyl group having 1 to 20 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom, a fluorine-containing alkoxy group having 1 to 20 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom, R ²² and R ²³ each independently represent a single bond, -O-, -COO-, -OCO- or an alkanediyl group having 1 to 3 carbon atoms, k, m and n satisfy 1? K + m + n? 4 When R ²¹ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms or a fluorine atom, k + m + n? 2 is satisfied. "*" Indicates a bonding hand.

Specific examples of the group represented by the formula (5) include, for example, groups represented by each of the following formulas (5-1) to (5-10), but the present invention is not limited thereto. Examples of the substituent which A ^{1 to} A ³ may have in the ring part include a fluorine atom, an alkyl group having 1 to 3 carbon atoms, and an alkoxy group having 1 to 3 carbon atoms. k + m + n is preferably an integer of 2 to 4.

(In the formula, &quot; * &quot;

The polymerization reaction using the (meth) acrylic monomer is preferably carried out by radical polymerization. Examples of the polymerization initiator used in the polymerization reaction include 2,2'-azobis (isobutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis Azo compounds such as azobis (4-methoxy-2,4-dimethylvaleronitrile); Organic peroxides such as benzoyl peroxide, lauroyl peroxide, t-butyl peroxy pivalate, 1,1'-bis (t-butylperoxy) cyclohexane; Hydrogen peroxide; And a redox-type initiator comprising these peroxides and a reducing agent. Of these, azo compounds are preferred. These polymerization initiators may be used alone or in combination of two or more. The proportion of the polymerization initiator to be used is preferably 0.01 to 50 parts by mass, more preferably 0.1 to 40 parts by mass based on 100 parts by mass of the total amount of the monomers used in the reaction.

The polymerization of the (meth) acrylic monomer is preferably carried out in an organic solvent. Examples of the organic solvent used in the reaction include alcohols, ethers, ketones, amides, esters, and hydrocarbon compounds. Of these, at least one selected from the group consisting of alcohols and ethers is preferably used, and it is more preferable to use partial ethers of polyhydric alcohols. Specific preferred examples thereof include diethylene glycol methyl ethyl ether, propylene glycol monomethyl ether acetate, and the like. These organic solvents may be used alone or in combination of two or more.

In the polymerization reaction of the (meth) acrylic monomer, the reaction temperature is preferably 30 to 120 占 폚, and more preferably 60 to 110 占 폚. The reaction time is preferably 1 to 36 hours, more preferably 2 to 24 hours. The amount (a) of the organic solvent used is preferably such that the total amount (b) of the monomers used in the reaction is from 0.1 to 50 mass% with respect to the total amount (a + b) of the reaction solution. The reaction solution containing poly (meth) acrylate may be directly supplied to the preparation of a liquid crystal aligning agent, or the poly (meth) acrylate contained in the reaction solution may be isolated and provided in the preparation of a liquid crystal aligning agent.

The number average molecular weight (Mn) in terms of polystyrene measured by gel permeation chromatography (GPC) of the poly (meth) acrylate is preferably such that the liquid crystal alignability of the formed liquid crystal alignment film is improved, Is preferably 250 to 500,000, more preferably 500 to 100,000, and still more preferably 1,000 to 50,000 from the viewpoint of ensuring stability of the film.

The content of the poly (meth) acrylate in the liquid crystal aligning agent is preferably in the range of from 0.01 to 10 parts by weight, more preferably from 0.1 to 10 parts by weight, from the viewpoint of obtaining a sufficiently high transparency of the liquid crystal device 10, Is preferably from 3 to 99% by mass relative to the total amount of the components. The content is more preferably 5% by mass or more, still more preferably 20% by mass, and particularly preferably 50% by mass, based on the lower limit of the content. When the effect of improving various properties by the polymer different from poly (meth) acrylate is obtained with respect to the upper limit value of the content ratio of poly (meth) acrylate, it is more preferably 95% by mass or less, Is 90 mass% or less. The poly (meth) acrylate may be used singly or in combination of two or more kinds.

(Other components)

The liquid crystal aligning agent used for forming the liquid crystal alignment films 14 and 15 is preferably selected from the group consisting of a silane compound and a polysiloxane together with poly (meth) acrylate in that a liquid crystal device 10 having high weather resistance can be obtained It is preferable to contain at least one species. It is particularly preferable that the liquid crystal aligning agent contains a polysiloxane in that the effect of improving the weatherability is high and further the post baking temperature can be further lowered. Further, the liquid crystal aligning agent preferably contains a silane compound from the viewpoint that adhesion to a substrate can be further enhanced.

(Polysiloxane)

The polysiloxane can be obtained, for example, by hydrolysis and condensation of a hydrolyzable silane compound. Examples of the silane compound include tetraalkoxysilane compounds such as tetramethoxysilane and tetraethoxysilane; Alkyl group or aryl group-containing alkoxysilane compounds such as methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, and dimethyldiethoxysilane;

Sulfur-containing alkoxysilane compounds such as 3-mercaptopropyltriethoxysilane and mercaptomethyltriethoxysilane;

Glycidoxypropyltrimethoxysilane, glycidoxymethyltrimethoxysilane, glycidoxymethyltriethoxysilane, 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane , Epoxy group-containing alkoxysilane compounds such as 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane;

Unsaturated bond-containing alkoxy groups such as 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, 3- (meth) acryloxypropylmethyldiethoxysilane and vinyltriethoxysilane Silane compounds;

Aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, n- (2-aminoethyl) -3-aminopropyltri 3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, n-ethoxycarbonyl-3 Nitrogen-containing alkoxysilane compounds such as aminopropyltrimethoxysilane;

Alkoxysilane compounds containing acid anhydride groups such as trimethoxysilylpropylsuccinic anhydride; And the like. These hydrolysable silane compounds may be used alone or in combination of two or more. In addition, "(meth) acryloxy" is meant to include "acryloxy" and "methacryloxy".

The above-mentioned hydrolysis-condensation reaction is carried out by reacting one or more of the above-mentioned hydrolyzable silane compounds with water, preferably in the presence of a suitable catalyst and an organic solvent. In the reaction, the use ratio of water is preferably 1 to 30 mol, relative to 1 mol of the hydrolyzable silane compound (total amount). Examples of the catalyst to be used include an acid, an alkali metal compound, an organic base, a titanium compound, and a zirconium compound. The amount of the catalyst to be used varies depending on the kind of catalyst, reaction conditions such as temperature, and the like, and it is preferably 0.01 to 3 moles per mole of the total amount of the silane compound. As the organic solvent to be used, for example, hydrocarbons, ketones, esters, ethers, alcohols and the like can be given. Of these, it is preferable to use an organic solvent which is non-water-soluble or lightly water-soluble. The use ratio of the organic solvent is preferably 10 to 10,000 parts by mass based on 100 parts by mass of the total amount of the silane compounds used in the reaction.

The above hydrolysis-condensation reaction is preferably carried out by heating, for example, in an oil bath. At this time, the heating temperature is preferably 130 占 폚 or less, and the heating time is preferably 0.5 to 12 hours. After completion of the reaction, the organic solvent layer separated from the reaction liquid is dried with a desiccant, if necessary, and then the solvent is removed to obtain the intended polysiloxane. The method of synthesizing the polysiloxane is not limited to the hydrolysis-condensation reaction described above, but may be carried out, for example, by a method in which the hydrolyzable silane compound is reacted in the presence of oxalic acid and an alcohol.

A polysiloxane having a functional group on the side chain such as a photo-aligning group or a pre-tilt angle excitation (for example, a vertical aligning group shown below) may be contained in the liquid crystal aligning agent. The polysiloxane having such a functional group can be synthesized by, for example, synthesizing a polysiloxane having an epoxy group in its side chain by polymerization using at least a part of the starting material, using a hydrolyzable silane compound containing an epoxy group, and then reacting the polysiloxane having an epoxy group with a And then reacting it with carbonic acid. Alternatively, a polymerization method using a hydrolyzable silane compound having a functional group in a monomer may be employed.

The reaction of the epoxy group-containing polysiloxane with the carboxylic acid is preferably carried out in the presence of a catalyst and an organic solvent. The use ratio of the carbonic acid is preferably 5 mol% or more, and more preferably 10 to 80 mol%, based on the epoxy group of the epoxy group-containing polysiloxane. As the catalyst, known compounds such as so-called curing accelerators which promote the reaction of organic bases and epoxy compounds can be used. The use ratio of the catalyst is preferably 100 parts by mass or less based on 100 parts by mass of the epoxy group-containing polysiloxane.

Specific preferred examples of the organic solvent to be used include 2-butanone, 2-hexanone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, and butyl acetate. The organic solvent is preferably used in such a proportion that the solid content concentration is 5 to 50 mass%. The reaction temperature in the above reaction is preferably 0 to 200 占 폚, and the reaction time is preferably 0.1 to 50 hours. After completion of the reaction, the organic solvent layer separated from the reaction liquid is dried with a desiccant, if necessary, and then the solvent is removed to obtain a polysiloxane having a functional group.

The polysiloxane preferably has a group capable of vertically aligning the liquid crystal molecules (hereinafter also referred to as &quot; vertical aligning group &quot;). Specific examples of the vertically aligning group include an alkyl group having from 8 to 22 carbon atoms, a fluorine-containing alkyl group having from 6 to 18 carbon atoms, a group represented by the above formula (5), and a group having from 17 to 51 carbon atoms having a steroid skeleton. . When a polysiloxane having a vertically aligning group is contained in the liquid crystal aligning agent, the light transmittance and light scattering properties of the obtained liquid crystal device can be further improved, which is preferable.

With regard to the polysiloxane, the weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC) is preferably 500 to 1,000,000, more preferably 1,000 to 100,000, and further preferably 1,000 to 50,000.

The content of the polysiloxane in the liquid crystal aligning agent is preferably 1% by mass or more, more preferably 2% by mass or more, based on the total amount of the polymer components in the liquid crystal aligning agent, from the viewpoint of sufficiently raising the weatherability of the obtained liquid crystal device By mass, more preferably 5% by mass or more. The upper limit of the content of the polysiloxane is preferably 97 mass% or less, and more preferably 90 mass% or less. The polysiloxane may be used singly or in combination of two or more kinds.

(Silane compound)

The silane compound contained in the liquid crystal aligning agent is an organic silicon compound having a carbon-silicon bond, and specific examples thereof include a hydrolyzable silane compound exemplified as a silane compound used for the synthesis of a polysiloxane. Art silane compound, an alkoxysilyl group (a -Si (OR) _3-r R _r (R is an alkyl group, r is an integer from 1 to 3. A plurality of R's may be the same or different from each other.)) To have a And more preferably an alkoxysilane compound having at least one functional group selected from the group consisting of an epoxy group, an amino group and a thiol group, and an epoxy group-containing alkoxysilane compound is particularly preferable.

When the silane compound is compounded in the liquid crystal aligning agent, the blending ratio thereof is preferably 0.5 parts by mass or more based on 100 parts by mass of the total of the polymers from the viewpoint of sufficiently obtaining the effect of improving the adhesion to the substrate and the weather resistance of the liquid crystal element 10 , More preferably from 1 to 30 parts by mass. The silane compounds may be used singly or in combination of two or more.

(Polymer having photo-orientable group)

The liquid crystal aligning agent used for forming the liquid crystal alignment films 14 and 15 preferably contains a polymer having a photo aligning group. Here, the "photo-alignable group" means a functional group that imparts anisotropy to the film by a photo-isomerization reaction by photoirradiation, a photo-dimerization reaction, a photodegradation reaction, and a light-free potential reaction. Specific examples of the photo-aligning group include, for example, azobenzene-containing groups containing azobenzene or derivatives thereof as basic skeletons, cinnamic acid structure-containing groups containing cinnamic acid or derivatives thereof as basic skeletons, and chalcone or derivatives thereof as basic skeletons Containing group containing a chalcone-containing group, a benzophenone or a derivative thereof as a basic skeleton, a coumarin-containing group containing a coumarin or a derivative thereof as a basic skeleton, a cyclobutane-containing group And the like. Among these, a group containing a cinnamic acid structure is preferable from the viewpoint of high sensitivity to light, and for example, a group having a partial structure represented by the following formula (1) can be given.

(In the formula (1), R represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a fluorine-containing alkyl group having 1 to 10 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom, A fluorine-containing alkoxy group having 1 to 10 carbon atoms, or a fluorine atom, and a is an integer of 0 to 4. When a is 2 or more, plural Rs may be the same or different. .)

In the partial structure represented by the formula (1), it is preferable that one of the two bonding hands "*" is bonded to a group represented by the following formula (4). In this case, the light transmittance and the light scattering property of the resulting liquid crystal device can be enhanced, which is preferable.

(In the formula (4), R ¹¹ represents a phenylene group, a biphenylene group, a terphenylene group, a cyclohexylene group or a bicyclohexylene group, an alkyl group having 1 to 20 carbon atoms, alkoxy group, at least one hydrogen atom with a fluorine atom may have a fluorine-containing alkoxy group, or a fluorine atom of the fluorinated alkyl group of the optionally substituted 1 to 20 carbon atoms, at least one hydrogen atom substituted with a fluorine atom having 1 to 20 carbon atoms. R ¹² , An alkanediyl group having 1 to 3 carbon atoms, an oxygen atom, a sulfur atom, -CH = CH-, -NH-, -COO- or -OCO (1) -, and when it is bonded to a carbonyl group in the formula (1), it is a single bond, an alkanediyl group having 1 to 3 carbon atoms, an oxygen atom, a sulfur atom or -NH-.

The photo-alignment group may have a poly (meth) acrylate, but it may have a polymer different from the poly (meth) acrylate. Examples of the main skeleton of the polymer having a photo-aligning group include polyamic acid, polyamic acid ester, polyimide, polysiloxane, polyamide and the like. From the viewpoint of securing the reliability and weatherability of the liquid crystal element 10, polysiloxane having a photo aligning group can be preferably used.

The method of synthesizing the polymer having photo-alignment groups is not particularly limited, and may be appropriately selected depending on the main skeleton of the polymer. Specific examples thereof include: (1) a method of polymerizing using a monomer having a photo-aligning group; (2) a method of synthesizing a polymer having a first functional group (for example, an epoxy group or the like) in a side chain, A method of reacting a reactive compound having a bifunctional group (e.g., a carboxyl group) and a photo-aligning group with a polymer having a first functional group, and the like. When the polymer having a photo-orientable group is polysiloxane, it is preferable to use the method (2) in that the introduction efficiency into the side chain is high.

In the case where the liquid crystal aligning agent contains a polymer having a photo aligning group and a polymer having no photo aligning group, the content ratio of the polymer having photo aligning group is preferably such that the coating film formed using a liquid crystal aligning agent has sufficient alignment properties Is preferably 1% by mass or more, more preferably 5% by mass to 99% by mass with respect to the total amount of the polymer components in the liquid crystal aligning agent.

The polymer component contained in the liquid crystal aligning agent is not limited to the above-mentioned poly (meth) acrylate and polysiloxane, and may include other polymer. Examples of the other polymer include polyamic acid, polyimide, polyamic acid ester, polyamide, polyester, cellulose derivative, polyacetal, polystyrene derivative, poly (styrene phenylmaleimide) derivative and the like. As the other polymer, at least one member selected from the group consisting of polyamic acid and polyamic acid ester is preferable, and polyamic acid is more preferable.

The blending ratio of the other polymer is preferably 20 mass% or less, more preferably 10 mass% or less, further preferably 5 mass% or less, based on the total amount of the polymer components in the liquid crystal aligning agent Do. The other polymer may be used singly or in combination of two or more.

(Crosslinking agent)

The liquid crystal aligning agent preferably contains, as other components, a compound having a crosslinkable group (hereinafter also referred to as a crosslinking agent). The crosslinkable group is a group capable of forming a covalent bond between the same or different molecules by light or heat, and examples thereof include a (meth) acryloyl group, a group having a vinyl group (alkenyl group, vinylphenyl group, etc.), an ethynyl group, A carboxyl group, a (protected) isocyanate group, and the like. Among them, (meth) acryloyl group is particularly preferable in view of high reactivity. The term &quot; (meth) acryloyl &quot; means acryloyl and methacryloyl. The number of crosslinkable groups of the crosslinking agent may be one or plural. From the viewpoint of sufficiently increasing the reliability of the liquid crystal device, it is preferably two or more, and more preferably two to six.

Specific examples of the crosslinking agent include allyl group-containing compounds such as diallyl phthalate;

Acrylates such as ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, pentaerythritol tri (Meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, trimethylol propane (meth) acrylate, ethoxylated trimethylolpropane tri (Meth) acrylate, ethylene glycol tri (meth) acrylate, polyether (meth) acrylate, ethoxylated bisphenol A di (meth) acrylate, tricyclodecanedimethanol di (Meth) acrylic compounds such as 8-octanediol di (meth) acrylate;

Maleic acid, itaconic acid, trimellitic acid, tetracarboxylic acid, cis-1,2,3,4-tetrahydrophthalic acid, ethylene glycol bistrimate, propylene glycol bistrimate, 4,4'-oxydiphthalic acid, Carbonic acid such as acetic anhydride or the like;

Ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, N, N ', N'-tetraglycidyl ether, glycerine diglycidyl ether, 2,2-bis (4-hydroxyphenyl) propane diglycidyl ether, trimethylolpropane triglycidyl ether, (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ', N'-tetraglycidyl-4,4'-dia Epoxy compounds such as minodiphenylmethane, N, N-diglycidyl-benzylamine, N, N-diglycidylaminomethylcyclohexane and N, N-diglycidyl-cyclohexylamine;

(Protected) isocyanate compounds in which a polyisocyanate such as tolylene diisocyanate, hexamethylene diisocyanate and diphenylmethylene diisocyanate is protected with a protecting group, and the like. As the crosslinking agent, among these, a polyfunctional (meth) acrylate compound is preferable.

The blending ratio of the crosslinking agent is preferably at least 0.5 part by mass, more preferably at least 0.5 part by mass, and most preferably at least 0.5 part by mass, relative to 100 parts by mass of the polymer component used for preparing the liquid crystal aligning agent, from the viewpoint of sufficiently obtaining the effect of improving the liquid crystal alignability and electrical properties. 40 parts by mass, and more preferably 5 to 30 parts by mass. The crosslinking agent may be used singly or in combination of two or more kinds.

(Antioxidant)

The liquid crystal aligning agent preferably contains, as other components, an antioxidant (also referred to as a polymerization inhibitor). The antioxidant has a function of retarding or inhibiting polymerization by negating radicals or peroxides generated by energy such as ultraviolet rays or heat. By including such an antioxidant in the alignment film, the polymerization reaction of the polymerizable compound in the liquid crystal composition existing in the vicinity of the surface of the alignment film is suppressed and the effect of suppressing the deterioration of the orientation property of the liquid crystal can be obtained. Specific examples of the antioxidant include, for example, a compound having an amine structure (preferably a hindered amine structure), a compound having a phenol structure (preferably a hindered phenol structure), a compound having an alkyl phosphate structure An antioxidant), a compound having a thioether structure (a sulfur-based antioxidant), and a mixture thereof (blend-based antioxidant).

Preferred examples of the antioxidant include compounds having an amine structure such as adecastab LA-52, LA-57, LA-63, LA-68, LA-72, LA-77, LA-502, LA-502 (manufactured by ADEKA), CHIMASSORB 119, CHIMASSORB 2020, CHIMASSORB 944, TINUVIN 622, TINUVIN 123, TINUVIN 144, TINUVIN 765, TINUVIN 770, TINUVIN 111, TINUVIN 783, TINUVIN 791 (manufactured by BASF Japan) or the like;

As the compound having a phenol structure, for example, adecastab AO-20, copper AO-30, copper AO-40, copper AO-50, copper AO-60, copper AO-80, copper AO-330 IRGANOX 1035, IRGANOX 1098, IRGANOX 1335, IRGANOX 1330, IRGANOX 1726, IRGANOX 1425, IRGANOX 1520, IRGANOX 245, IRGANOX 259, IRGANOX 3114, IRGANOX 3790, IRGANOX 5057, IRGANOX 565 (manufactured by ADEKA) , IRGAMOD 295 (manufactured by BASF Japan) or the like;

PEP-8, copper PEP-36, HP-10, 2112 (manufactured by ADEKA) and GSY-P 101 (manufactured by Sakai Chemical Industries, Ltd.) IRGAFOS 168, IRGAFOS 12, IRGAFOS 126, IRGAFOS 38 and IRGAFOS P-EPQ (manufactured by BASF Japan);

Examples of the sulfur-based antioxidant include adecastab AO-412, AO-503 (manufactured by ADEKA), IRGANOX PS 800, IRGANOX PS 802 (manufactured by BASF Japan);

Examples of the blend-based antioxidant include adecastab A-611, A-612, A-613, AO-37, AO-15, AO-18 and 328 (manufactured by ADEKA) 111, TINUVIN 783, and TINUVIN 791 (manufactured by BASF Japan). As the antioxidant, one of them may be used alone, or two or more of them may be used in combination.

The content of the antioxidant in the liquid crystal aligning agent is preferably 0.01 to 15 parts by mass, more preferably 0.01 to 10 parts by mass, per 100 parts by mass of the polymer component used for preparing the liquid crystal aligning agent, Particularly preferably 0.1 to 10 parts by mass.

Examples of other components contained in the liquid crystal aligning agent include metal chelate compounds, curing accelerators, surfactants, fillers, dispersants, photosensitizers and the like. The blending ratio of these other components can be appropriately selected depending on each compound within the range not detracting from the effect of the present disclosure.

(menstruum)

The liquid crystal aligning agent is prepared as a liquid composition in which the polymer component and other components to be used, if necessary, are dissolved in a suitable solvent.

Examples of the organic solvent to be used include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, But are not limited to, butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, 4-hydroxy- Ethylene glycol-n-propyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol diisopropyl ether, ethylene glycol diisopropyl ether, Ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol mono ethyl Thermal acetate, and the like can be given propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, di-isopentyl ether, ethylene carbonate, propylene carbonate. These may be used alone or in combination of two or more.

The organic solvent used for the preparation of the liquid crystal aligning agent is preferably at least one selected from the group consisting of an organic solvent and an organic solvent in order to obtain a liquid crystal alignment film exhibiting good device characteristics even when the post-baking temperature is lowered (for example, Is preferably 40 mass% or more, more preferably 50 mass% or more, and even more preferably 70 mass% or more, with respect to the total amount of the solvent.

The solid concentration of the liquid crystal aligning agent (the ratio of the total mass of components other than the solvent of the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., 10% by mass. When the solid concentration is less than 1% by mass, the film thickness of the coating film becomes too small to obtain a good liquid crystal alignment film. On the other hand, when the solid concentration exceeds 10% by mass, the film thickness of the coating film becomes excessively large, and it is difficult to obtain a good liquid crystal alignment film, and the viscosity of the liquid crystal aligning agent tends to increase and the coatability tends to decrease.

<Manufacturing Method of Liquid Crystal Device>

Next, a manufacturing method of the liquid crystal element 10 will be described. The liquid crystal device 10 includes a process A for forming liquid crystal alignment films 14 and 15 by applying a liquid crystal aligning agent to the electrode arrangement surfaces of the first base 11 and the second base 12, A step B of arranging a pair of substrates having the liquid crystal cell layers 14, 15 so as to face each other with the electrode arrangement faces thereof being opposed to each other with the liquid crystal composition layer interposed therebetween; a step B of curing the polymerizable compound Lt; RTI ID = 0.0 &gt; C. &Lt; / RTI &gt;

(Process A)

The application of the liquid crystal aligning agent may be carried out on the respective electrode placement surfaces of the first base material 11 and the second base material 12 by using, for example, an offset printing method, a spin coating method, a roll coater method, , A flexo printing method, or the like. After the application of the liquid crystal aligning agent, preheating (prebaking) is preferably performed for the purpose of preventing the liquid flow of the applied liquid crystal aligning agent or the like. The prebaking temperature is set in accordance with the kind of the base material, but it is preferably 140 占 폚 or lower, more preferably 120 占 폚 or lower, and even more preferably 100 占 폚 or lower. The lower limit value of the prebaking temperature is preferably 30 DEG C or higher, more preferably 40 DEG C or higher. The prebaking time is preferably 0.25 to 10 minutes.

Thereafter, a baking (post-baking) step is preferably carried out for the purpose of completely removing the solvent and, if necessary, promoting the crosslinking reaction. The baking temperature (post-baking temperature) at this time is preferably 160 ° C or lower, more preferably 150 ° C or lower, and particularly preferably 110 ° C or lower, when a substrate made of a polymer material is used. By making at least a part of the polymer component of the liquid crystal aligning agent be poly (meth) acrylate, solubility in a low-boiling solvent can be improved, and even when the post-baking temperature is lowered, a homogeneous alignment film can be obtained, It becomes possible to secure the liquid crystal alignment property and the voltage holding ratio of the element 10. The post baking time is preferably 5 to 200 minutes, and more preferably 10 to 120 minutes.

(Photo-alignment treatment)

The coating film formed using the liquid crystal aligning agent is preferably subjected to rubbing treatment, photo alignment treatment, or the like to give liquid crystal aligning ability. In the present embodiment, a photo alignment treatment is performed to give a liquid crystal aligning ability by irradiating light.

In the photo alignment treatment, light irradiation to the coating film may use radiation such as ultraviolet rays and visible rays including light having a wavelength of 150 to 800 nm, for example. The radiation may be polarized light or unpolarized light, or may be irradiated in combination. The exposure method is not particularly limited, and examples thereof include a method of irradiating linearly polarized light in a direction perpendicular to a substrate surface or an oblique direction, and a method of irradiating unpolarized light in an oblique direction.

As the light source to be used, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp and an excimer laser can be used. The ultraviolet ray in the preferable wavelength range can be obtained by a means for using the light source together with, for example, a filter, a diffraction grating, or the like. The irradiation dose of the radiation is preferably 10 to 50,000 J / m 2, and more preferably 20 to 10,000 J / m 2. The light irradiation for the photo-alignment treatment may be carried out by a method of irradiating the coating film after the post-baking step, a method of irradiating the coating film before the post-baking step after the pre-baking step, a pre- And a method in which the coating film is irradiated during heating.

(Step B)

In Step B, two substrates each having a liquid crystal alignment film are prepared, and a liquid crystal cell is produced by arranging a liquid crystal composition and a layer of a liquid crystal composition containing a polymerizable compound between two substrates opposed so that the liquid crystal alignment film is opposed to each other. Specifically, the periphery of the first base material 11 and the second base material 12 are bonded by a sealant, and the liquid crystal composition is injected and filled in the cell gap defined by the substrate surface and the sealant, How to bag; A sealing agent is applied to the peripheral portion of the substrate on one side of the liquid crystal alignment film and a liquid crystal composition is dropped to a predetermined number of places on the liquid crystal alignment film side and then the other substrate is bonded so as to face the liquid crystal alignment film, (ODF method) in which the sealant is spread over the entire surface of the substrate and then the sealant is cured. As the sealing agent, for example, an epoxy resin containing an aluminum oxide sphere as a curing agent and a spacer can be used.

(Step C)

In the step C, at least one kind of treatment selected from heating and light irradiation is performed to cure the liquid crystal composition. The heating temperature at the time of the curing reaction is appropriately selected depending on the kinds of the polymerizable compound and the liquid crystal to be used, and is heated, for example, at a temperature in the range of 40 to 80 캜. The heating time is preferably 0.5 to 5 minutes. In the case of curing by light irradiation, unpolarized ultraviolet light having a wavelength in the range of 200 to 500 nm is preferably used as the irradiation light. The irradiation dose of light is preferably 50 to 10,000 mJ / cm 2, more preferably 100 to 5,000 mJ / cm 2.

The liquid crystal element 10 can be applied to various applications such as a window of a building, a partition of an indoor space and an outdoor space, a window of a show window, a window of a vehicle (an automobile, an aircraft, a ship, And can be effectively used as various light control elements such as various advertisements, guide signs, home electric appliances, mobile phones, smart phones, various monitors, watches, portable games, personal computers, glasses, sunglasses, medical instruments and furniture. The liquid crystal element 10 may be used as it is, depending on the thickness and hardness of the element, shape, application, etc., and may be adhered to glass or a transparent resin.

(Liquid crystal device)

The display device of the present disclosure includes the above-described liquid crystal element and a transparent display which becomes transparent in a non-display state. Specifically, as shown in Fig. 3, the display device 20 has a structure in which the liquid crystal element 10 is disposed on the back surface of the transparent display 30, and the liquid crystal element 10 functions as a light control element , The visibility of the display of the transparent display 30 is changed.

The transparent display 30 is, for example, an organic electroluminescence element (organic EL element), and includes a pair of glass substrates, a cathode electrode and a cathode electrode formed of a transparent electrode material, and a cathode electrode And a hole transporting layer and a light emitting layer formed thereon. In the non-display state of the transparent display 30, the transparent display 30 is entirely transparent and is applied with a voltage, so that the voltage-applied pixel emits light, and characters and images are displayed.

In the display device 20 of Fig. 3, when the liquid crystal element 10 and the transparent display 30 are in the voltage-unapplied state, the entire surface of the display device 20 becomes transparent. Therefore, for example, when the display device 20 is applied as a front glass or a rear glass of a show window, it is possible to view a product displayed on a display case or a display in a point from the outside. In addition, when a voltage is applied to the transparent display 30 in a state in which the liquid crystal element 10 is in a voltage-unapplied state, characters and images displayed on the transparent display 30 are displayed in a floating state on the glass.

On the other hand, in a state where a voltage is applied to the liquid crystal element 10, the back surface of the transparent display 30 is shielded. In this case, the characters, images, and the like displayed on the display device 20 and the objects behind the display device 20 can be prevented from overlapping, and the display of the transparent display 30 becomes easy to see. It is also possible to enhance the decorative property. Alternatively, a configuration may be employed in which the degree of light transmission from the front surface of the display device 20 to the back surface is varied by controlling the voltage applied to the liquid crystal element 10 in accordance with the brightness of the front surface or the back surface of the display device 20 Maybe.

In the display device 20 of Fig. 3, the liquid crystal element 10 may be arranged only in a part of the transparent display 30. Alternatively, the display area of the transparent display 30 may be divided into a plurality of areas, and a light control element may be provided for each display area so that the transmissivity can be changed for each display area.

In the above embodiment, the liquid crystal alignment films 14 and 15 were used as the photo alignment film, but the photo alignment treatment may not be performed. In this case also, when a substrate made of a polymer material is used as the base material of the liquid crystal element 10, the liquid crystal alignment film is homogeneous, the liquid crystal alignment film has high transparency, light transmission property and light scattering property are good, It is possible to obtain a liquid crystal device that exhibits sufficient electric characteristics in realization and is excellent in weather resistance.

Example

Hereinafter, the contents of this disclosure will be described more specifically by way of examples, but the contents of this disclosure are not limited to these examples.

In the following examples, the weight average molecular weight (Mw), the number average molecular weight (Mn) and the epoxy equivalent of the polymer and the solution viscosity of the polymer solution were measured by the following methods. The necessary amounts of the starting compounds and polymers used in the following examples were ensured by repeating the synthesis on the synthesis scale shown in the following synthesis examples as necessary.

[Weight average molecular weight (Mw) and number average molecular weight (Mn) of the polymer]

Mw and Mn are polystyrene reduced values measured by GPC under the following conditions.

Column: TSKgelGRCXLII, manufactured by Tosoh Corporation

Solvent: tetrahydrofuran

Temperature: 40 ° C

Pressure: 68kgf / ㎠

[Epoxy equivalent]

The epoxy equivalent was measured by the hydrochloric acid-methyl ethyl ketone method described in JIS C 2105.

[Solution viscosity of polymer solution]

The solution viscosity (mPa s) of the polymer solution was measured at 25 캜 using an E-type rotational viscometer.

The abbreviations of the compounds used in the following examples are as follows. Hereinafter, for convenience, the "compound represented by formula (X)" is simply referred to as "compound (X)".

(Carbonic acid)

(Polymerizable compound)

(Photoinitiator)

(Crosslinking agent)

(Silane compound)

(Antioxidant)

(Dichromatic dye)

<Synthesis of poly (meth) acrylate>

[Synthesis Example 1]

1.2 parts by mass of 2,2'-azobisisobutyronitrile and 200 parts by mass of propylene glycol monomethyl ether acetate were fed into a flask equipped with a cooling tube and a stirrer. Subsequently, 80 parts by mass of glycidyl methacrylate and 20 parts by mass of styrene were charged, and after purging with nitrogen, stirring was started slowly. The solution temperature was raised to 95 占 폚, and this temperature was maintained (maintained) for 5 hours to obtain a polymer solution containing the polymer (Pac-1). The consumption rate (consumption rate) of the monomer after completion of the reaction calculated from the measurement result of the solid content concentration of the polymer solution was 99%.

[Synthesis Example 2]

1.2 parts by mass of 2,2'-azobisisobutyronitrile and 200 parts by mass of propylene glycol monomethyl ether acetate were fed into a flask equipped with a cooling tube and a stirrer. Subsequently, 50 parts by mass of glycidyl methacrylate and 50 parts by mass of tricyclo [5.2.1.0 ^2,6 ] deca-8-yl methacrylate were charged, and after nitrogen replacement, stirring was started slowly. The solution temperature was raised to 95 占 폚, and this temperature was maintained for 5 hours to obtain a polymer solution containing the polymer (Pac-2). Further, the consumption rate of the monomer after completion of the reaction calculated from the measurement result of the solid content concentration of the polymer solution was 99%.

&Lt; Synthesis of polysiloxane having epoxy group >

[Synthesis Example 3]

100 g of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (ECETS), 500 g of methyl isobutyl ketone and 10.0 g of triethylamine were placed in a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel and a reflux condenser tube Were added and mixed at room temperature. Subsequently, 100 g of deionized water was added dropwise from the dropping funnel over 30 minutes, and the mixture was reacted at 80 DEG C for 6 hours while mixing under reflux. After completion of the reaction, the organic layer was taken out and washed with a 0.2 mass% ammonium nitrate aqueous solution until the washed water became neutral, and then the solvent and water were distilled off under reduced pressure to obtain a polysiloxane having an epoxy group as a viscous transparent liquid . As a result of ¹ H-NMR analysis of the polysiloxane having the epoxy group, it was confirmed that a peak based on the epoxy group was obtained near the chemical shift (?) = 3.2 ppm, and no side reaction of the epoxy group occurred during the reaction. The weight average molecular weight (Mw) of the polysiloxane (SEp-1) having an epoxy group obtained in Synthesis Example 3 was 2,200 and the epoxy equivalent was 186 g / mol.

<Synthesis of polysiloxane having a functional group>

[Synthesis Example 4]

18.4 g of the polysiloxane (SEp-1) having an epoxy group obtained in Synthesis Example 3, 70.8 g of methyl isobutyl ketone, 3.45 g of a carboxylic acid (CA-1) as a cinnamic acid derivative (polyorganosiloxane SEP-1), 6.21 g of a carboxylic acid (CA-2) as a cinnamic acid derivative (25 parts by mol per 100 parts by mol of the epoxy group of the polysiloxane (SEp-1)) and tetrabutylammonium bromide And the mixture was stirred at 80 占 폚 for 12 hours. After the completion of the reaction, 40 g of diethylene glycol diethyl ether and 60 g of cyclohexane were added, and this solution was washed with water for 6 times by washing with water. Then, another 100 g of diethylene glycol diethyl ether was added, %. &Lt; / RTI &gt; Thus, a diethylene glycol diethyl ether solution containing a polymer (S-1) as a polysiloxane having a functional group and having a solid concentration of 10% by mass was obtained. The polymer (S-1) had a weight average molecular weight (Mw) of 17,000.

[Synthesis Example 5 and Synthesis Example 6]

(S-2) and (S-3) as the polysiloxane having a functional group were synthesized in the same manner as in Synthesis Example 4, except that the kinds and amounts of the carbonic acid used in the reaction were changed as shown in Table 1 . The numbers in Table 1 indicate the number of moles per 100 moles of the epoxy group of the polysiloxane (SEp-1).

<Synthesis of polyamic acid>

[Synthesis Example 7]

121.35 g of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as a tetracarboxylic acid dianhydride (90 molar parts relative to the total amount of diamine used in the synthesis: 90 molar parts), and 3,5-diaminobenzoic acid colester N-methyl-2-pyrrolidone (NMP) were dissolved in 94.34 g (30 molar parts of copper) and 4,4'-diaminodiphenyl ether of 84.3 g The reaction was carried out. The reaction mixture was then poured into a large excess of methanol and the reaction product was precipitated. The collected precipitate was washed with methanol and then dried at 40 DEG C for 15 hours under reduced pressure to obtain 290 g of polyamic acid (hereinafter referred to as polymer (PAA-1)). The obtained polymer (PAA-1) was adjusted to 20% by mass with NMP, and the viscosity of this solution was measured and found to be 1310 mPa · s. When the polymer solution was allowed to stand at 20 캜 for 3 days, gelation did not occur and storage stability was good.

<Synthesis of polyimide>

[Synthesis Example 8]

3.19 g (12.8 mmol) of 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4, 6: 8-2 anhydride as tetracarboxylic acid dianhydride and 1,3- (11.6 mmol) of diamino-4- 4- (trans-4-n-heptylcyclohexyl) phenoxymethyl] benzene and 2.16 g (14.2 mmol) of 3,5-diaminobenzoic acid were dissolved in 24.9 g of NMP , 2.50 g (12.8 mmol) of 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride and 12.4 g of NMP as a tetracarboxylic acid dianhydride were added, and the mixture was stirred at 40 ° C The reaction was carried out for 8 hours to obtain a polyamic acid solution having a polymer concentration of 25 mass%. NMP was added to 30.0 g of the obtained polyamic acid solution to dilute it to 6 mass%, 3.95 g of acetic anhydride and 2.40 g of pyridine were added, and the mixture was reacted at 50 ° C for 2 hours. The reaction mixture was then poured into a large excess of methanol and the reaction product was precipitated. The recovered precipitate was washed with methanol and then dried at 100 캜 under reduced pressure to obtain a polyimide (hereinafter referred to as polymer (PI-1)). The imidization ratio of the obtained polyimide was 55% and the weight average molecular weight was 48,000.

&Lt; Preparation of liquid crystal composition &

1. Preparation of liquid crystal composition I

1.20 g of a liquid crystal (MLC-6608, manufactured by Merck), 1.20 g of a compound (R-1) as a polymerizable compound, 0.60 g of a compound (R-2), 0.12 g of a compound (R- R-4) and 0.012 g of the compound (P-1) as a photoinitiator were mixed, and the mixture was heated to 25 占 폚 to obtain liquid crystal composition I.

2. Preparation of liquid crystal composition II

1.20 g of the liquid crystal (MLC-6608, manufactured by Merck), 0.024 g of the dichroic dye shown below, 1.20 g of the compound (R-1) as the polymerizable compound, 0.60 g of the compound (R-2) 0.12 g of the compound (R-3), 0.36 g of the compound (R-4) and 0.012 g of the compound (P-1) as the photoinitiator were mixed and heated to 25 占 폚 to obtain liquid crystal composition II.

(Dichromatic dye)

, 6.0 parts by mass of the compound (m-1), 2.0 parts by mass of the compound (m-2) and 2.0 parts by mass of the compound (m-3)

[Example 1]

&Lt; Preparation of liquid crystal aligning agent &

An amount corresponding to 20 parts by mass of the polymer (S-1) in terms of the amount of the diethylene glycol diethyl ether solution containing the polymer (S-1) obtained in Synthesis Example 4, The solution containing the polymer (Pac-1) was mixed in an amount corresponding to 80 parts by mass in terms of the polymer (Pac-1) and 5 parts by mass of the compound (add-2) (PGME), diethylene glycol diethyl ether (DEDG) and propylene glycol monomethyl ether acetate (PGMEA) were added, and the solid content concentration was 4 mass% and the weight ratio of each solvent was PGME: DEDG: PGMEA = 30:20 : 50. Subsequently, this obtained solution was filtered with a filter having a pore size of 0.2 탆 to prepare a liquid crystal aligning agent (A-1).

&Lt; Evaluation of liquid crystal aligning agent and liquid crystal element &

1. Evaluation of Coating Property

The liquid crystal aligning agent (A-1) prepared above was coated on the surface of the substrate of the PET film substrate (PET-ITO substrate) having the ITO electrode using a bar coater and heated on a hot plate at 80 캜 for 1 minute After pre-baking, the coating was heated (post-baking) in an oven at 120 캜 in which the inside of the oven was replaced by nitrogen for 2 minutes to form a coating film having an average film thickness of 0.1 탆. This coating film was observed with a naked eye and a microscope having a magnification of 100 times to investigate film thickness unevenness, coating irregularity, and presence of pinholes. The evaluation was evaluated as "good" when the film thickness irregularity, coating irregularity and pinhole were not observed even when observed with a naked eye and a microscope of 100 times, "pinhole" was observed with a microscope having a magnification of 100, In the case where the film was not observed was evaluated as &quot; acceptable &quot;, and at least one of film thickness nonuniformity, coating irregularity and pinholes was visually observed by visual observation as coating performance &quot; defective &quot;. In the present example, neither naked eye nor 100-fold microscope showed any unevenness in film thickness, unevenness in coating and pinholes, and the coating was "good".

2. Evaluation of transparency of coating film

The coating film obtained in the above 1. was evaluated for transparency of the coating film by the light transmittance (%) at a wavelength of 400 nm using a spectrophotometer (150-20 type double beam manufactured by Hitachi Seisakusho Co., Ltd.) did. In the evaluation, transparency was "good" when the light transmittance was 97% or more, and transparency was "poor" when the light transmittance was less than 97%. As a result, the coating film had a light transmittance of 98.1% and a transparency of &quot; good &quot;.

3. Manufacturing of Liquid Crystal Device

A 20 mJ / cm 2 polarized ultraviolet ray including a 313 nm bright line was irradiated from the direction tilted 20 ° from the substrate normal by using an Hg-Xe lamp and a Glane Taylor prism on the surface of the coating film prepared in the above 1., . The same operation was repeated to prepare a pair of substrates (two substrates) each having a liquid crystal alignment film. Subsequently, a spacer having a thickness of 6 mu m was coated on the surface of the liquid crystal alignment film having one base material, and then the liquid crystal composition I prepared above was dropped on the surface of the liquid crystal alignment film coated with the spacer. Subsequently, the two substrates were bonded together with a sealant so that the liquid crystal alignment film surface of the other substrate was opposed to each other to obtain a liquid crystal cell. This liquid crystal cell was irradiated with ultraviolet rays under the conditions of a wavelength of 365 nm, an ultraviolet ray intensity of 15 mW / cm 2, an irradiation time of 15 seconds, and a substrate surface temperature of 20 캜 using an ultraviolet light emitting device using an ultraviolet light emitting diode as a light source, And cured to obtain the liquid crystal element 10 shown in Fig.

4. Evaluation of light transmittance

The haze (haze) of the liquid crystal device in the voltage unapplied state was measured to evaluate the transparency when the voltage was not observed. The measurement was performed using a spectroscopic haze meter (manufactured by Tokyo Denshoku Co., Ltd.). The lower the haze value, the better the transparency. As a result, in this example, the haze value was 2%, and the transparency was excellent in the voltage unapplied state.

5. Evaluation of light scattering property

The haze (HAZE) of the liquid crystal device under the voltage application state was measured to evaluate the light scattering property upon voltage application. The measurement was carried out by using a spectroscopic haze meter (manufactured by Tokyo Denshoku Co., Ltd.) in the same manner as in the above-mentioned 4. above, by applying 20 V to the liquid crystal device manufactured in the above-mentioned 3. under AC driving. The higher the haze value, the better the light scattering property. As a result, in this embodiment, the haze value was 92%, and the light scattering property in the voltage application state was excellent.

6. Evaluation of Voltage Conservation Rate

The voltage compensation ratio (VHR _BF ) after 1670 milliseconds from the application of the voltage was measured after application of a voltage of 5 V at 23 캜 for an application time of 60 microseconds and a span of 167 milliseconds to the liquid crystal device prepared in the above 3. As a result, the voltage holding ratio was 80.4%. As a measuring apparatus, VHR-1 (manufactured by Toyotecnica Co., Ltd.) was used.

7. Evaluation of weatherability

The liquid crystal device prepared in the above 3. was irradiated with xenon lamp light (illuminance 250 W / m 2 (300-800 nm)) for 200 hours by a light resistance tester (SUNTEST CPS + manufactured by Toyo Seiki). With respect to the liquid crystal device after light irradiation, the voltage holding ratio was measured by the same method as in 6. above. This value was used as the voltage _maintenance ratio (VHR _AFXe ) after light irradiation. The decrease rate? VHR _Xe (%) of the voltage holding ratio was obtained from the following equation (EX-1) and the weather resistance was evaluated based on the decrease rate? VHR _Xe .

? VHR _Xe = ((VHR _BF - VHR _AFXe ) / VHR _BF ) x 100 ... (EX-1)

, The case where ΔVHR _Xe was less than 5% was evaluated as "good", the case where it was less than 5% and less than 10% was judged as "possible", and the case of 10% or more was judged as "poor". As a result,? VHR _Xe of the liquid crystal device of this example was 3.5%, and the weather resistance was "good".

The haze value in the voltage unapplied state was measured for the liquid crystal device after light irradiation for 200 hours in the same manner as in the above-mentioned 4, and the weather resistance was evaluated based on the haze value. As a result, in the liquid crystal device of this example, the haze value after light irradiation was 2%, and the transparency did not change before and after light irradiation.

[Examples 2 to 7 and Comparative Example 1]

The respective liquid crystal aligning agents (A-2) to (A-8) were prepared in the same manner as in the preparation of the liquid crystal aligning agent (A-1) except that the components shown in Table 2 were used, did. The liquid crystal devices were evaluated in the same manner as in Example 1 by using each of the liquid crystal aligning agents (A-2) to (A-8). The results are shown in Table 3 below.

[Example 8]

1. Manufacturing and Evaluation of Liquid Crystal Device

A liquid crystal device was produced in the same manner as in Example 1 except that the liquid crystal composition II was used instead of the liquid crystal composition I. Evaluation was carried out in the same manner as in Example 1 using the obtained liquid crystal device. The results are shown in Table 3 below.

In Example 8, the following evaluations (evaluation of light transmittance, evaluation of light blocking property, and evaluation of repetitive driving endurance test) were performed using the liquid crystal device prepared in the above-mentioned 1. above.

2. Evaluation of light transmittance

The transmittance of the liquid crystal device in a voltage unapplied state was measured to evaluate the transparency when the voltage was not observed. The light transmittance was evaluated by the light transmittance (%) at a wavelength of 400 nm using a spectrophotometer (150-20 type double beam manufactured by Hitachi Seisakusho Co., Ltd.). The higher the transmittance value, the better the transparency. As a result, the transmittance in the present example was 93%, and the transparency was excellent in the voltage unapplied state.

3. Evaluation of light blocking property

The transmittance of the liquid crystal device under a voltage applied state was measured to evaluate the light blocking property at the time of voltage application. The measurement was carried out by applying AC voltage of 40 V to the liquid crystal device manufactured in the above 1. and using a spectrophotometer (150-20 type double beam manufactured by Hitachi Seisakusho Co., Ltd.) I did. The lower the transmittance value, the better the light shielding property. As a result, the transmittance was 5% in this example, and the light shielding property in the voltage application state was excellent.

4. Evaluation of repeated drive endurance test

A voltage of 40 V was applied to the liquid crystal element for 1 second, and then the liquid crystal element was left unattended for 1 second. After repeating this operation 1800 times, evaluations of light transmittance and light shielding properties were carried out in the same manner as in the above 2. and 3. to evaluate the repeated drive endurance test. As a result, in the present embodiment, the transmittance at a voltage-unapplied state of 93% and the transmittance at a voltage application of 7% were observed before and after driving, The increase was only 2%. From this result, it can be said that the liquid crystal device of this embodiment is excellent in repetitive drive durability.

The numerical values in Table 2 show the compounding ratio (parts by mass) of each compound to the total 100 parts by mass of the polymer components used for preparing the liquid crystal aligning agent.

In Table 2, the abbreviations are as follows.

PGME: Propylene glycol monomethyl ether

PGMEA: Propylene glycol monomethyl ether acetate

DEDG: Diethylene glycol diethyl ether

NMP: N-methyl-2-pyrrolidone

GBL:? -Butyrolactone

As can be seen from Table 3, the liquid crystal alignment film containing poly (meth) acrylate is homogeneous and has high transparency even when the post-baking temperature is low (120 占 폚) Characteristics and light scattering characteristics were good. In addition, the obtained liquid crystal device had a sufficiently high voltage holding ratio and good weather resistance. In particular, Examples 1 and 2, which contained a poly (meth) acrylate and a polysiloxane in a liquid crystal alignment film and had a high proportion of poly (meth) acrylate, exhibited excellent performances, light transmittance, light scattering properties, did. Example 7 containing an antioxidant in a liquid crystal alignment film showed a haze value of a voltage-unapplied visibility and a haze value after an evaluation of weather resistance as compared with Example 4 in which an antioxidant was not included in the liquid crystal alignment film It was excellent.

Also in Example 8 in which the coloring matter (dichroic dye) was dispersed in the liquid crystal layer, the obtained voltage-holding ratio of the liquid crystal element was sufficiently high and the weather resistance was good. Further, even after the liquid crystal element was repeatedly subjected to the voltage application / no application, the light shielding property and the light transmittance were both good, and the driving durability was excellent. This behavior is believed to be due to an assist from the alignment film side.

On the other hand, Comparative Example 1 comprising a liquid crystal alignment film made of polyimide was inferior to those of Examples in terms of coatability and transmittance of the coating film, and light transmittance and weatherability (haze value) of the liquid crystal device.

&Lt; Display test in combination with transparent display >

[Example 9]

A display device in which the liquid crystal devices prepared in Example 2 were superimposed on each other on the outer surface of one side of the transparent display was manufactured and the transparent display was displayed. As a result, the liquid crystal device was found to have good transmittance in the voltage- The visibility of the display was judged to be &quot; good &quot;.

[Comparative Example 2]

A display test was carried out in the same manner as in Example 9 except that a liquid crystal element of a polarizing plate method was used in lieu of the liquid crystal element of Example 9. [ As a polarizing plate type liquid crystal device, a liquid crystal cell in which a transparent electrode and a liquid crystal alignment film are formed on respective opposing surfaces of a pair of glass substrates, a liquid crystal is filled between the pair of substrates, And a polarizing plate disposed on the outer side of the substrate. As a result, in Comparative Example 2, the light transmittance of the liquid crystal element was poor and the visibility of the display of the transparent display was judged to be &quot; defective &quot;. This indicates that the light transmittance of the PDLC element using the acrylic resin is good. On the other hand, in a polarizing plate type liquid crystal device, since light is absorbed in the polarizing plate, the transmittance is theoretically not more than 50%, and the visibility of the transparent display is poor. From the above, it can be said that the liquid crystal device 10 having a liquid crystal alignment film containing poly (meth) acrylate as a display device overlapping each other in the transparent display is particularly excellent.

Although the present disclosure has been described in accordance with the embodiment, it is understood that the present disclosure is not limited to the above embodiment or structure. This disclosure includes various modifications and variations within the scope of equivalents. In addition, various combinations or forms, and further combinations or forms, including only one element, more or less than those elements, fall within the scope and spirit of the present disclosure.

10: liquid crystal element
11: First substrate
12: second substrate
13: liquid crystal layer
14, 15: Liquid crystal alignment film
16, 17: transparent electrode
20: Display device
30: Transparent display

Claims (14)

A pair of substrates disposed opposite to each other,
An electrode disposed on the surfaces of the pair of substrates facing each other,
A liquid crystal layer disposed between the pair of substrates and formed by curing a liquid crystal composition containing a liquid crystal and a polymerizable compound,
And a liquid crystal alignment film formed on at least one electrode arrangement surface of the pair of substrates,
Wherein the liquid crystal composition comprises at least one member selected from the group consisting of a monofunctional (meth) acrylate compound, a polyfunctional (meth) acrylate compound, a polyfunctional thiol compound and a styrene compound,
Wherein the liquid crystal alignment layer is formed by a liquid crystal aligning agent containing poly (meth) acrylate. The method according to claim 1,
Wherein the content of the poly (meth) acrylate in the liquid crystal aligning agent is 3 to 99% by mass relative to the total amount of the polymer components contained in the liquid crystal aligning agent. 3. The method according to claim 1 or 2,
Wherein the liquid crystal aligning agent further contains a polysiloxane. 4. The method according to any one of claims 1 to 3,
Wherein the liquid crystal aligning agent contains a polymer having a photo-orientable group. 5. The method according to any one of claims 1 to 4,
Wherein the liquid crystal aligning agent further contains a silane compound. 6. The method according to any one of claims 1 to 5,
Wherein the liquid crystal aligning agent further contains a compound having a crosslinkable group. 7. The method according to any one of claims 1 to 6,
Wherein the liquid crystal composition further contains a coloring matter. 8. The method of claim 7,
Wherein the coloring matter is at least one selected from the group consisting of an azo compound and an anthraquinone compound. 9. The method according to any one of claims 1 to 8,
Wherein the liquid crystal composition further contains an antioxidant. 10. A display device comprising the liquid crystal device according to any one of claims 1 to 9 and a transparent display which becomes transparent in a non-display state. As a liquid crystal aligning agent for forming a liquid crystal alignment film of a liquid crystal device having a liquid crystal layer formed by curing a liquid crystal composition containing a liquid crystal and a polymerizable compound between a pair of substrates arranged so that electrodes formed on respective substrate surfaces face each other, A liquid crystal aligning agent containing poly (meth) acrylate. And a liquid crystal layer formed by curing a liquid crystal composition comprising a liquid crystal and a polymerizable compound between a pair of substrates arranged so that electrodes formed on the respective substrate surfaces face each other,
A step of applying a liquid crystal aligning agent on at least one electrode arrangement surface of the pair of substrates to form a liquid crystal alignment film,
A step of arranging the pair of substrates so that the electrodes are opposed to each other via a layer including the liquid crystal composition after formation of the liquid crystal alignment film to construct a liquid crystal cell,
And curing the polymerizable compound after the liquid crystal cell is constructed,
Wherein the liquid crystal composition comprises at least one member selected from the group consisting of a monofunctional (meth) acrylate compound, a polyfunctional (meth) acrylate compound, a polyfunctional thiol compound and a styrene compound,
Wherein the liquid crystal aligning agent contains poly (meth) acrylate. 13. The method of claim 12,
And the liquid crystal aligning agent coated on the electrode placement surface is heated at 160 캜 or lower. The method according to claim 12 or 13,
Wherein the liquid crystal aligning agent is applied on at least one electrode arrangement surface of the pair of substrates to form a coating film and light is irradiated to the coating film to give liquid crystal alignment ability to the coating film.

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