JP2012083734A - Polymerizable liquid crystal composition and optical film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polymerizable liquid crystal composition capable of easily manufacturing an optical film having a smectic phase oriented in a horizontal direction formed therein.SOLUTION: In the polymerizable liquid crystal composition which contains a polymerizable liquid crystal compound showing a smectic phase, a leveling agent and a solvent, the leveling agent is at least one selected from the group consisting of a leveling agent containing a polyacrylate compound as a main component and a leveling agent containing a fluorine atom-containing compound as a main component, and the content of the leveling agent is 0.3 pt.mass or more and 5 pts.mass or less with respect to 100 pts.mass of the polymerizable liquid crystal compound.

Description

  The present invention relates to a polymerizable liquid crystal composition and an optical film.

  Optical films such as polarizing films and retardation films are used for liquid crystal display devices. Moreover, it is known that such an optical film is manufactured using, for example, a polymerizable liquid crystal composition containing a polymerizable liquid crystal compound, a photopolymerization initiator, and a solvent (see, for example, Patent Document 1).

Special table 2008-547062 gazette

  In a conventionally known polymerizable liquid crystal composition, it may not always be easy to produce an optical film in which a smectic phase aligned in the horizontal direction is formed.

The present invention provides the following [1] to [8].
[1] A polymerizable liquid crystal compound exhibiting a smectic phase, a leveling agent and a solvent,
The leveling agent is at least one selected from the group consisting of a leveling agent mainly composed of a polyacrylate compound and a leveling agent mainly composed of a fluorine atom-containing compound,
A polymerizable liquid crystal composition, wherein the content of the leveling agent is 0.3 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the polymerizable liquid crystal compound.

[2] The polymerizable liquid crystal compound according to [1], wherein the polymerizable liquid crystal compound has a temperature exhibiting a nematic phase within a temperature range between a temperature exhibiting a smectic phase and a temperature exhibiting an isotropic phase. Polymerizable liquid crystal composition.
[3] The polymerizable liquid crystal composition according to [1] or [2], further comprising a dichroic dye.
[4] An optical film obtained by polymerizing the polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition according to any one of [1] to [3].

[5] A method for producing an optical film, comprising the steps of (1) to (3).
(1) Step (2) in which the polymerizable liquid crystal composition according to any one of [1] to [3] is applied onto a substrate to obtain a coating film (2) The liquid crystal phase forms the coating film obtained in (1) Steps (3) and (2) for converting to a formed film Polymerizing the polymerizable liquid crystal compound contained in the film formed by the liquid crystal phase obtained in (2) to obtain an optical film

[6] The production method according to [5], wherein the liquid crystal phase is a smectic phase.
[7] In (2), the coating film obtained in (1) is heated to a temperature at which the polymerizable liquid crystal compound contained in the coating film exhibits a nematic phase, and then the polymerizable liquid crystal compound is smectic. The production method according to [5] or [6], wherein the coating film is cooled to a temperature showing a phase to convert to a film in which a smectic phase is formed.
[8] An optical film obtained by the production method according to any one of [5] to [7].
[9] A display device comprising the optical film according to [4] or [8].

  According to the polymerizable liquid crystal composition of the present invention, an optical film in which a smectic phase aligned in the horizontal direction is formed can be easily obtained. An optical film in which a smectic phase oriented in the horizontal direction is formed is particularly excellent in dichroic ratio.

It is the schematic showing the liquid crystal display device 10 of this invention. It is the schematic showing the liquid crystal display device 24 of this invention. It is the schematic showing the EL display apparatus 30 of this invention. It is the schematic showing the EL display apparatus 44 of this invention. It is the schematic showing the projection type liquid crystal display device of this invention.

  As described above, the polymerizable liquid crystal composition of the present invention includes a polymerizable liquid crystal compound exhibiting a smectic phase, a specific leveling agent, and a solvent. The leveling agent is at least one selected from the group consisting of a leveling agent mainly composed of a polyacrylate compound and a leveling agent mainly composed of a fluorine atom-containing compound, and the content of the leveling agent is determined by polymerization. 0.3 to 5 parts by mass with respect to 100 parts by mass of the liquid crystalline compound.

An optical film refers to a film that can transmit light and has an optical function. The optical function means absorption, reflection, diffraction, scattering, refraction, birefringence and the like. A retardation film, which is a kind of optical film, is used for converting linearly polarized light into circularly polarized light or elliptically polarized light, or conversely converting circularly polarized light or elliptically polarized light into linearly polarized light.
In addition, a polarizing film, which is a kind of optical film, is used to decompose incident light that is not polarized into two orthogonally polarized components, transmit one polarized component, and absorb the other polarized component. . The axial direction of the transmitted polarization component is called the transmission axis, and the axial direction of the polarized component to be absorbed is called the absorption axis.

  In a conventional polymerizable liquid crystal composition (for example, a polymerizable liquid crystal composition described in Patent Document 1), when the polymerizable liquid crystal composition is applied on an alignment film, the polymerizable liquid crystal contained in the polymerizable liquid crystal composition In the case where an optical film is obtained by polymerizing the polymerizable liquid crystal compound after the compound is made into a film showing a smectic phase (film having a liquid crystal phase formed), the polymerizable liquid crystal compound in the film in which the liquid crystal phase is formed For example, it is difficult to obtain an optical film having an excellent dichroic ratio. For this reason, it is necessary to produce a cell in which two alignment films face each other, and there is a problem that the operation is complicated. According to the polymerizable liquid crystal composition of the present invention, the film in which the liquid crystal phase is formed by coating can be a film in which the polymerizable liquid crystal compound is sufficiently oriented in the horizontal direction (film surface direction). An optical film having an excellent color ratio can be obtained.

The polymerizable liquid crystal composition of the present invention contains a polymerizable liquid crystal compound. The polymerizable liquid crystal compound is a compound having a polymerizable group and exhibiting liquid crystallinity. The polymerizable group means a group involved in the polymerization reaction of the polymerizable liquid crystal compound.
The polymerizable liquid crystal compound is a polymerizable liquid crystal compound showing a smectic phase, and has a temperature showing a nematic phase within a temperature range between a temperature showing a smectic phase and a temperature showing an isotropic phase. A compound is preferred. When the polymerizable liquid crystal compound is such a compound, a horizontally aligned smectic phase tends to be easily obtained.

Having a temperature indicating a nematic phase within a temperature range between a temperature indicating a smectic phase and a temperature indicating an isotropic phase means that the temperature indicating the smectic phase is Ts (° C.) and the temperature indicating the isotropic phase is When Ta (° C.) and the temperature showing the nematic phase are Tn (° C.), the formula (T1)
Ts <Tn <Ta (T1)
Satisfying the relationship.

  The smectic phase is selected from a smectic A phase, a smectic B phase, a smectic D phase, a smectic E phase, a smectic F phase, a smectic G phase, a smectic H phase, a smectic I phase, a smectic J phase and a smectic K phase. The smectic phase is inclined. Among these, a smectic B phase, a smectic F phase, a smectic I phase, a tilted smectic F phase and a tilted smectic I phase are preferable, and a smectic B phase is more preferable. When the liquid crystal phase (smectic phase) exhibited by the polymerizable liquid crystal compound is such a liquid crystal phase, an optical film having a high degree of alignment order can be obtained.

Examples of the polymerizable liquid crystal compound include a compound represented by the formula (1) (hereinafter sometimes referred to as “compound (1)”).

^{U 1 -V 1 -W 1 -X 1} -Y 1 -X 2 -Y 2 -X 3 -W 2 -V 2 -U 2 (1)

[In Formula (1), X ¹ , X ² and X ³ represent a p-phenylene group which may have a substituent or a cyclohexane-1,4-diyl group which may have a substituent. . However, at least one of X ¹ , X ² and X ³ represents a p-phenylene group which may have a substituent.
Y ¹ and ^{Y 2,} independently of one _{another, -CH 2 CH 2 -, -} CH 2 O -, - COO -, - OCOO-, a single ^{bond, -N = N -, - CR} a = CR b -, - C≡C— or —CR ^a ═N— is represented. Represents.
R ^a and R ^b each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.
U ¹ represents a hydrogen atom or a polymerizable group.
U ² represents a polymerizable group.
W ¹ and W ² each independently represent a single bond, —O—, —S—, —COO— or —OCOO—.
V ¹ and V ² each independently represent an optionally substituted alkanediyl group having 1 to 20 carbon atoms, and —CH ₂ — contained in the alkanediyl group represents —O—, — S- or -NH- may be substituted. ]

X ¹ , X ² and X ³ are each independently a p-phenylene group which may have a substituent, or a cyclohexane-1,4-diyl group which may have a substituent. . However, at least one of X ¹ , X ² and X ³ is a 1,4-phenylene group which may have a substituent.
At least two of X ¹ , X ² and X ³ are preferably a p-phenylene group which may have a substituent.
The p-phenylene group is preferably unsubstituted. The cyclohexane-1,4-diyl group is preferably a trans-cyclohexane-1,4-diyl group, and more preferably unsubstituted.

Examples of the substituent that the p-phenylene group may have include an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, and a butyl group; a cyano group; a halogeno group such as a fluoro group, a chloro group, and a bromo group Etc.
Examples of the substituent that the cyclohexane-1,4-diyl group may have include an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, and a butyl group; a cyano group; a fluoro group, a chloro group, Examples include halogeno groups such as bromo group. Hexane-1,4-diyl -CH group ₂ cycloheteroalkyl - is, -O -, - may be substituted with S- or -NR-. R is a C1-C6 alkyl group or a phenyl group.

Y ¹ and ^{Y 2,} independently of one _{another, -CH 2 CH 2 -, -} CH 2 O -, - COO -, - OCOO-, a single ^{bond, -N = N -, - CR} a = CR b -, - C≡C— or —CR ^a ═N—. The bonding position of these groups may be any direction.
R ^a and R ^b are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, and a butyl group.
Y ¹ is preferably —CH ₂ CH ₂ —, —COO—, or a single bond.
Y ² is preferably —CH ₂ CH ₂ — or —CH ₂ O—.

U ¹ is a hydrogen atom or a polymerizable group, and preferably a polymerizable group. U ² is a polymerizable group. U ¹ and U ² are preferably both photopolymerizable groups. Here, the photopolymerizable group refers to a group that can participate in polymerization by an active radical, an acid, or the like generated from a photopolymerization initiator. U ¹ and U ² are preferably the same type of group.
Examples of the polymerizable group include a vinyl group, vinyloxy group, 1-chlorovinyl group, isopropenyl group, 4-vinylphenyl group, acryloyloxy group, methacryloyloxy group, oxiranyl group, and oxetanyl group. Among them, acryloyloxy group, methacryloyloxy group, vinyloxy group, oxiranyl group and oxetanyl group are preferable, and acryloyloxy group is more preferable.

V ¹ and V ² are each independently an alkanediyl group having 1 to 20 carbon atoms which may have a substituent, and —CH ₂ — contained in the alkanediyl group is —O—, — S- or -NH- may be substituted.
Examples of the alkanediyl group having 1 to 20 carbon atoms include methylene group, ethylene group, propane-1,3-diyl group, butane-1,3-diyl group, butane-1,4-diyl group, and pentane-1,5. -Diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, decane-1,10-diyl group, tetradecane-1,14-diyl group and icosane -1,20-diyl group etc. are mentioned, Preferably it is a C2-C12 alkanediyl group, More preferably, it is a C6-C12 alkanediyl group.
Examples of the substituent that the alkanediyl group may have include a cyano group; a halogeno group such as a fluoro group, a chloro group, and a bromo group.
The alkanediyl group is preferably an unsubstituted alkanediyl group, and more preferably an unsubstituted linear alkanediyl group.

W ¹ and W ² are each independently a single bond, —O—, —S—, —COO— or —OCOO—, preferably a single bond or —O—.

  Examples of the compound (1) include compounds represented by formula (1-1) to formula (1-21). In the formula, the cyclohexane-1,4-diyl group is preferably a trans isomer.

  The content of the compound (1) in the polymerizable liquid crystal composition of the present invention is preferably in the range of 70 to 99.9% by mass and more preferably in the range of 90 to 99.9% by mass with respect to the solid content of the composition. preferable. If it is in the said range, there exists a tendency for the orientation of a compound to become high. Here, solid content means the total amount of the component remove | excluding the solvent from the composition. Compound (1) may be used alone or in combination of two or more.

  The polymerizable liquid crystal composition of the present invention contains a leveling agent. The leveling agent has a function of adjusting the fluidity of the polymerizable liquid crystal composition and flattening the applied film, and examples thereof include a surfactant. The leveling agent contained in the polymerizable liquid crystal composition of the present invention is at least one selected from the group consisting of a leveling agent mainly composed of a polyacrylate compound and a leveling agent mainly composed of a fluorine atom-containing compound. By containing such a leveling agent, when the polymerizable liquid crystal composition of the present invention obtains a film in which the liquid crystal phase is formed, the polymerizable liquid crystal compound is aligned in the horizontal direction in the film. The inventor found out. The manifestation of such an effect cannot be easily recalled from conventional polymerizable liquid crystal compositions, and is based on the inventors' original knowledge.

  As a leveling agent mainly composed of a polyacrylate compound, BYK-350, BYK-352, BYK-353, BYK-354, BYK-355, BYK-358N, BYK-361N, BYK-380, BYK-381, BYK -392 (both trade names: BYK Chemie) and the like.

  As a leveling agent having a fluorine atom-containing compound as a main component, Megafac (trade name) R-08, R-30, R-90, F-410, F-411, F-443, F-445, F-470, F-471, F-477, F-479, F-482, F-482 (all of which are manufactured by DIC Corporation), Surflon (trade name) S-381, S-382, S-383, S-393, SC-101, SC-101, SC-105, KH-40, SA-100 (all are manufactured by AGC Seimi Chemical Co., Ltd.), products Examples include E1830, E5844 (produced by Daikin Fine Chemical Laboratory Co., Ltd.), EF301 (trade name) EF301, EF303, EF351, EF352 (all produced by Mitsubishi Materials Electronics Chemical Co., Ltd.).

  The content of the leveling agent in the polymerizable liquid crystal composition of the present invention is 0.3 part by mass or more and 5 parts by mass or less, preferably 0.5 part by mass or more and 3 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. Or less. The polymerizable liquid crystal composition of the present invention contains a specific leveling agent in a larger amount than usual, thereby enabling production of an optical film in which a smectic phase aligned in the horizontal direction is formed. When the content of the leveling agent is within the above range, it is easy to horizontally align the polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition, and the resulting optical film tends to be smooth. If the content of the leveling agent exceeds 5 parts by mass, the resulting optical film is likely to be uneven. Two or more of these leveling agents may be used in combination. When two or more kinds of leveling agents are used in combination, the total content may be in the above range.

  The polymerizable liquid crystal composition of the present invention may contain a dichroic dye. When the polymerizable liquid crystal composition of the present invention is a composition containing a polymerizable liquid crystal compound, a dichroic dye, a leveling agent, and a solvent, the obtained optical film has a function as a polarizing film. The dichroic dye refers to a dye having a property that the absorbance in the major axis direction of the molecule is different from the absorbance in the minor axis direction.

  The dichroic dye is not particularly limited, and may be a dye or a pigment. The dichroic dye preferably has a maximum absorption wavelength at 300 to 700 nm. Examples of the dichroic dye include acridine dyes, oxazine dyes, cyanine dyes, naphthalene dyes, azo dyes and anthraquinone dyes. The dichroic dye may be used alone or in combination with a plurality of dichroic dyes.

  As the dichroic dye, an azo dye is preferable. Examples of the azo dye include monoazo dyes, bisazo dyes, trisazo dyes, tetrakisazo dyes, and stilbene azo dyes, and bisazo dyes and trisazo dyes are preferable.

Specific examples of the dichroic dye that can be used in the polymerized liquid crystal composition of the present invention are shown below.
As an azo dye, the compound represented by Formula (2) is mentioned, for example.
_{^{A 1 (-N = N-A}} 2) p -N = N-A 3 (2)
[In Formula (2), A ¹ and A ³ may each independently have a phenyl group which may have a substituent, a naphthyl group which may have a substituent, or a substituent. Represents a good monovalent heterocyclic group. A ² is each independently a p-phenylene group which may have a substituent, a naphthalene-1,4-diyl group which may have a substituent, or a substituent 2 which may have a substituent. Represents a valent heterocyclic group. p represents an integer of 1 to 4. When p is an integer greater than or equal to ² , several A2 may mutually be same or different. ]

  The monovalent heterocyclic group is a group in which one hydrogen atom is removed from a heterocyclic ring such as a quinoline ring, a thiazole ring, a benzothiazole ring, a thienothiazole ring, an imidazole ring, a benzimidazole ring, an oxazole ring, or a benzoxazole ring. Is mentioned. Moreover, as a bivalent heterocyclic group, the group remove | excluding two hydrogen atoms from said heterocyclic ring is mentioned.

The phenyl group, naphthyl group and monovalent heterocyclic group in A ¹ and A ³ , and the p-phenylene group, naphthalene-1,4-diyl group and divalent heterocyclic group in A ² may have. Examples of the substituent include an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group and a butyl group; an alkoxy group having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group and a butoxy group; carbon such as a trifluoromethyl group A fluorinated alkyl group having 1 to 4 carbon atoms; a cyano group; a nitro group; a halogeno group such as a fluoro group, a chloro group or a bromo group; an amino group; substituted with an alkyl group having 1 to 4 carbon atoms such as a diethylamino group or a pyrrolidino group. Amino groups (two alkyl groups substituted with amino groups may be bonded to each other to form an alkanediyl group having 2 to 8 carbon atoms).

As the azo dye, compounds represented by the following formulas (2-1) to (2-6) are preferable. In formulas (2-1) to (2-6), B ^{1 to} B ²⁰ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group, a nitro group, amino Group, an amino group substituted with an alkyl group having 1 to 4 carbon atoms (two alkyl groups substituted with amino groups may be bonded to each other to form an alkanediyl group having 2 to 8 carbon atoms), Represents a chloro group or a trifluoromethyl group. n1 to n4 each independently represents an integer of 0 to 3. If n1 is an integer of 2 or more, a plurality of ^{B 2} may be the same or different from each other, similarly when n2~n4 is an integer of 2 or more, a plurality of ^B 6, ^{B 9} and ^{B 14} are They may be the same or different from each other.

  As said anthraquinone pigment | dye, the compound represented by Formula (2-7) is preferable.

[In Formula (2-7), R ^{1 to} R ⁸ each independently represents a hydrogen atom, —R ^x , an amino group, —NHR ^x , —NR ^x ₂ , —SR ^x, or a halogen atom. R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

  As the acridine dye, a compound represented by the formula (2-8) is preferable.

[In Formula (2-7), R ^{9 to} R ¹⁵ each independently represent a hydrogen atom, —R ^x , an amino group, —NHR ^x , —NR ^x ₂ , —SR ^x, or a halogen atom. R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

  As the oxazone dye, a compound represented by the formula (2-9) is preferable.

[In Formula (2-9), R ^{9 to} R ¹⁵ each independently represent a hydrogen atom, —R ^x , an amino group, —NHR ^x , —NR ^x ₂ , —SR ^x, or a halogen atom. R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

In the above formula (2-7), formula (2-8) and formula (2-9),
Examples of the alkyl group having 1 to 4 carbon atoms in R ^x include a methyl group, an ethyl group, a propyl group, and a butyl group.
Examples of the aryl group having 6 to 12 carbon atoms in R ^x include a phenyl group, a toluyl group, a xylyl group, and a naphthyl group.

  As the cyanine dye, a compound represented by the formula (2-10) and a compound represented by the formula (2-11) are preferable.

ｎ５は１〜３の整数を表す。］ [In Formula (2-10), D ¹ and D ² each independently represent a group represented by Formula (2-10a) to Formula (2-10d).

n5 represents an integer of 1 to 3. ]

ｎ６は１〜３の整数を表す。］ [In Formula (2-11), D ³ and D ⁴ each independently represent a group represented by Formula (2-11a) to Formula (2-11h).

n6 represents an integer of 1 to 3. ]

  When the polymerizable liquid crystal composition of the present invention contains a dichroic dye, the content thereof is preferably 50 parts by mass or less, and 0.1 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the polymerizable liquid crystal compound. More preferred is 0.1 to 10 parts by mass. If it is in the said range, it can superpose | polymerize, without disturbing the orientation of a polymerizable liquid crystal compound. If the content of the dichroic dye exceeds 50 parts by mass, the orientation of the polymerizable liquid crystal compound may be disturbed, which is not preferable.

The polymerizable liquid crystal composition of the present invention contains a solvent. The solvent is preferably a solvent that can dissolve components other than the solvent contained in the polymerizable liquid crystal composition, such as a polymerizable liquid crystal compound. Moreover, it is preferable that it is a solvent inactive to the polymerization reaction of a polymeric liquid crystal composition.
Solvents include alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether and propylene glycol monomethyl ether; ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone Or ester solvents such as propylene glycol methyl ether acetate and ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; toluene And aromatic hydrocarbon solvents such as xylene, nitrile solvents such as acetonitrile; Hydrofuran and ether solvents such as dimethoxyethane; chlorine-containing solvents such as chloroform and chlorobenzene; and the like. These solvents may be used alone or in combination.

  As for content of the solvent in the polymeric liquid crystal composition of this invention, 50-98 mass% is preferable with respect to this polymeric liquid crystal composition whole quantity. In other words, the solid content in the polymerizable liquid crystal composition of the present invention is preferably 2 to 50% by mass. When the solid content is 2% by mass or more, the film thickness of the obtained optical film does not become too thin, and as a result, the dichroism necessary for the polarizer is obtained in the optical film. Moreover, since the viscosity of the polymeric liquid crystal composition of this invention is low as solid content is 50 mass% or less, in the manufacture of the optical film mentioned later, there exists a tendency for the film thickness of a coating film to become difficult to produce. In addition, solid content means the quantity remove | excluding the solvent from the polymeric liquid crystal composition.

  The polymerizable liquid crystal composition of the present invention may contain a polymerization initiator. The polymerization initiator is a compound that initiates polymerization of the polymerizable liquid crystal compound, and generates an active radical or an acid by the action of light and / or heat. Especially, it is preferable that it is a polymerization initiator (namely, photoinitiator) which generate | occur | produces an active radical or an acid by the effect | action of light, and the photoinitiator which generate | occur | produces a radical by light irradiation is more preferable.

  Examples of the photopolymerization initiator include benzoin compounds, benzophenone compounds, alkylphenone compounds, acylphosphine oxide compounds, triazine compounds, iodonium salts, and sulfonium salts.

Examples of the benzoin compound include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and the like.
Examples of the benzophenone compound include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4′-methyldiphenyl sulfide, 3,3 ′, 4,4′-tetra (tert-butylperoxycarbonyl). ) Benzophenone, 2,4,6-trimethylbenzophenone and the like.

  Examples of the alkylphenone compound include diethoxyacetophenone, 2-methyl-2-morpholino-1- (4-methylthiophenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl). ) Butan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1,2-diphenyl-2,2-dimethoxyethane-1-one, 2-hydroxy-2-methyl-1 -[4- (2-hydroxyethoxy) phenyl] propan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propane-1- ON oligomers and the like.

Examples of the acylphosphine oxide compound include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, and the like.
Examples of the triazine compound include 2,4-bis (trichloromethyl) -6- (4-methoxyphenyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (4-methoxy Naphthyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (4-methoxystyryl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6 [2- (5-Methylfuran-2-yl) ethenyl] -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (furan-2-yl) ethenyl] -1 , 3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (4-diethylamino-2-methylphenyl) ethenyl] -1,3,5-triazine, 2,4-bis (trichloro Methyl) -6 [2- (3,4-dimethoxyphenyl) ethenyl] -1,3,5-triazine.

  As photopolymerization initiators, Irgacure 907, Irgacure 184, Irgacure 651, Irgacure 819, Irgacure 250, Irgacure 369 (all are manufactured by Ciba Japan Co., Ltd.), Sake All BZ, Sequol Z, Sequol BEE (and above) , All manufactured by Seiko Chemical Co., Ltd.), kayacure BP100 (manufactured by Nippon Kayaku Co., Ltd.), Kayacure UVI-6992 (manufactured by Dow), Adekaoptomer SP-152 or Adekaoptomer SP-170 (or more) Commercially available photopolymerization initiators such as TAZ-A, TAZ-PP (manufactured by Nippon Shibel Hegner) and TAZ-104 (manufactured by Sanwa Chemical Co., Ltd.) can also be used.

  Examples of the thermal polymerization initiator include azo compounds such as azobisisobutyronitrile; peroxides such as hydrogen peroxide, persulfate, and benzoyl peroxide.

The content of the polymerization initiator is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 10 parts by mass, and further preferably 0.5 to 8 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. .
Within the above range, the polymerizable liquid crystal compound can be polymerized without disturbing its orientation.

  When using a photoinitiator as a polymerization initiator, you may use a photosensitizer together. Examples of the photosensitizer include xanthone compounds such as xanthone and thioxanthone (for example, 2,4-diethylthioxanthone and 2-isopropylthioxanthone); anthracene such as anthracene and an alkoxy group-containing anthracene (for example, dibutoxyanthracene). Compound; phenothiazine; rubrene and the like.

By using a photosensitizer, the polymerization of the polymerizable liquid crystal compound can be made highly sensitive.
When using a photosensitizer, the usage-amount is preferable 0.1-30 mass parts with respect to 100 mass parts of polymeric liquid crystal compounds, 0.5-10 mass parts is more preferable, 0.5-8 Part by mass is more preferable.

  The polymerizable liquid crystal composition of the present invention may contain a polymerization inhibitor. When the polymerizable liquid crystal composition of the present invention contains a polymerization inhibitor, the polymerization of the polymerizable liquid crystal compound can be controlled, and the stability of the polymerizable liquid crystal composition of the present invention can be improved.

Examples of the polymerization inhibitor include radical scavengers such as hydroquinone, alkoxy group-containing hydroquinone, alkoxy group-containing catechol (for example, butyl catechol), pyrogallol, 2,2,6,6-tetramethyl-1-piperidinyloxy radical, and the like. , Thiophenols, β-naphthylamines, β-naphthols and the like.
When the polymerizable liquid crystal composition of the present invention contains a polymerization inhibitor, the content thereof is preferably 0.1 to 30 parts by mass, and 0.5 to 10 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. More preferably, 0.5-8 mass parts is further more preferable. If it is in the said range, superposition | polymerization can be controlled, without disturbing the orientation of a polymerizable liquid crystal compound.

  The optical film of the present invention can be obtained by polymerizing the polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition of the present invention.

The optical film of this invention is obtained by the manufacturing method containing the following (1)-(3).
(1) Step of obtaining a coating film by applying the polymerizable liquid crystal composition of the present invention on a substrate (2) Step of converting the coating film obtained in (1) into a film in which a liquid crystal phase is formed (3 ) A step of polymerizing the polymerizable liquid crystal compound contained in the film formed by the liquid crystal phase obtained in (2) to obtain an optical film

  Examples of the coating method on the substrate include an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, a CAP coating method, a die coating method, a dip coating method, a bar coating method, and a spin coating method.

As said board | substrate, glass, a plastic sheet, a plastic film, or a translucent film can be mentioned, for example. Examples of the translucent film include polyolefin films made of polyolefins such as polyethylene, polypropylene, and norbornene polymers; polyvinyl alcohol films; polyethylene terephthalate films; polymethacrylate films; polyacrylate films; cellulose ester films; Naphthalate film; Polycarbonate film; Polysulfone film; Polyether sulfone film; Polyether ketone film; Polyphenylene sulfide film and polyphenylene oxide film.
If an optical film is produced using a substrate, the obtained optical film can be easily handled without being broken when transported or stored.

  In the method for producing an optical film of the present invention, an alignment film is preferably formed on the substrate. In that case, the polymerizable liquid crystal composition of the present invention is applied onto the alignment film. The alignment film preferably has a solvent resistance that does not dissolve when the polymerizable liquid crystal composition of the present invention is applied. Moreover, it is preferable to have heat resistance in the heat treatment for removing the solvent and aligning the liquid crystal. Furthermore, an alignment film that does not peel off due to friction due to rubbing or the like is preferable. Such an alignment film is preferably made of an alignment polymer.

  Examples of the orientation polymer include polyamides and gelatins having an amide bond in the molecule, polyimides having an imide bond in the molecule, and polyamic acid, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, polyacrylamide which are hydrolysates thereof. Mention may be made of polymers such as oxazole, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid or polyacrylic acid esters. Among these, polyvinyl alcohol is preferable. These alignment polymers forming the alignment film may be used alone or in combination of two or more. Further, the orientation polymer may be a copolymer having a plurality of structural units constituting the exemplified orientation polymer. These oriented polymers can be easily obtained by polycondensation by dehydration or deamine, chain polymerization such as radical polymerization, anion polymerization, and cation polymerization, coordination polymerization, and ring-opening polymerization.

  The alignment polymer can be formed on the substrate by applying the alignment polymer on the substrate as an alignment polymer composition (solution containing the alignment polymer) dissolved in a solvent. The solvent used in the alignment polymer composition is not particularly limited, but specifically, water; alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, methyl cellosolve, butyl cellosolve, and propylene glycol monomethyl ether Ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate and ethyl lactate; ketones such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, methyl amyl ketone and methyl isobutyl ketone Solvents; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; aromatic hydrocarbon solvents such as toluene and xylene, acetonitrile, etc. Tolyl solvent; tetrahydrofuran and ether solvents such as dimethoxyethane; and the like are; chlorinated hydrocarbon solvent of chloroform and chlorobenzene. These organic solvents may be used alone or in combination of two or more.

  A commercially available alignment film material may be used as it is as the alignment polymer composition for forming the alignment film. Examples of commercially available alignment film materials include Sunever (registered trademark, manufactured by Nissan Chemical Industries, Ltd.) and Optmer (registered trademark, manufactured by JSR).

  As a method for forming an alignment film on the substrate, for example, the alignment polymer composition or a commercially available alignment film material is applied on the substrate, and then annealed to align on the substrate. A film can be formed. The thickness of the alignment film thus obtained is, for example, 10 nm to 10000 nm, preferably 10 nm to 1000 nm.

  In order to impart an alignment regulating force to the alignment film, it is preferable to perform rubbing or polarized UV irradiation as necessary. By providing the alignment regulating force, the polymerizable liquid crystal compound can be aligned in a desired direction.

  As a method for rubbing the alignment film, for example, a rubbing cloth is wound and a rotating rubbing roll is prepared, and a rotating rubbing roll is prepared by placing an alignment film formed on a substrate on a stage. A method of bringing the rotating rubbing roll and the alignment film into contact with each other by conveying toward the surface is mentioned. Further, the alignment regulating force may be imparted to the alignment film by irradiating the alignment film with polarized light (preferably, polarized UV). If masking is performed when rubbing or polarized UV irradiation is performed, a plurality of regions (patterns) having different orientation directions can be formed.

  With respect to the coating film obtained by applying the polymerizable liquid crystal composition of the present invention on the substrate or the alignment film formed on the substrate, the volatilization of the solvent and the like contained in the coating film in terms of the film forming property. It is preferable to dry the sex component. Examples of the drying method include a natural drying method, a ventilation drying method, and a vacuum drying method. As drying temperature, 0-250 degreeC is preferable and 50-220 degreeC is more preferable. The drying time is preferably 10 seconds to 60 minutes, and more preferably 30 seconds to 30 minutes.

  In order to convert the coating film into a film in which a liquid crystal phase is formed, the coating film may be heated to a temperature at which the polymerizable liquid crystal compound contained in the coating film exhibits a liquid crystal phase. The liquid crystal phase is preferably a smectic phase due to the action of the polymerizable liquid crystal compound.

In order for the polymerizable liquid crystal compound contained in the coating film to exhibit a smectic phase (orient the polymerizable liquid crystal compound in the smectic phase), the coating film may be heated and then cooled. At that time, when the polymerizable liquid crystal compound satisfies the relationship of the above formula (T1), first, the temperature at which the polymerizable liquid crystal compound exhibits a nematic phase (Tn, where Tn is the “nematic phase transition”). It is more preferable to obtain a film in which the liquid crystal phase is formed by heating the coating film as described above and then cooling to a temperature (Ts) at which the polymerizable liquid crystal compound exhibits a smectic phase.
When the polymerizable liquid crystal composition of the present invention contains two or more kinds of polymerizable liquid crystal compounds, a mixture prepared by adjusting the polymerizable liquid crystal compound at a content ratio contained in the polymerizable liquid crystal composition is first prepared. With respect to the above, by measuring the temperature at which the liquid crystal phase is exhibited, the temperature conditions for producing an optical film from the polymerizable liquid crystal composition of the present invention containing two or more polymerizable liquid crystal compounds can be determined.

  By passing through the nematic phase in this way, the leveling agent contained in the polymerizable liquid crystal composition of the present invention becomes easier to flow, and a horizontally aligned film can be obtained more easily. The heating temperature for the polymerizable liquid crystal compound to exhibit a nematic phase is preferably in the range from the nematic phase transition point to a temperature not higher than 100 degrees higher than the nematic phase transition point, more than the nematic phase transition point and 50 degrees from the nematic phase transition point. The range below the high temperature is more preferable. In addition, you may perform simultaneously operation which heats a coating film until it shows a nematic phase, and drying operation which removes a volatile component from this coating film.

  Next, an optical film can be obtained by polymerizing the polymerizable liquid crystal compound contained in the film in which the liquid crystal phase is formed. By polymerizing the polymerizable liquid crystal compound, a durable optical film can be obtained. What is necessary is just to select the polymerization method according to the kind of polymeric group which a polymeric liquid crystal compound has. If the polymerizable group is a photopolymerizable group, it can be polymerized by a photopolymerization method, and if it is a thermopolymerizable group, it can be polymerized by a thermal polymerization method. In the method for producing an optical film of the present invention, a photopolymerization method is preferable. In the case of the photopolymerization method, since it is not always necessary to heat to a high temperature, a substrate having low heat resistance can be used. The photopolymerization method is performed by irradiating visible light, ultraviolet light, or laser light onto the film on which the liquid crystal phase is formed. In view of easy handling, ultraviolet light is preferable. The light irradiation is performed in a state where a liquid crystal phase is formed on the film. As described above, light irradiation may be performed at a temperature showing a liquid crystal phase. At this time, the optical film can be patterned by masking or developing.

  The optical film formed on the substrate may be peeled from the substrate after polymerization of the polymerizable liquid crystal compound contained in the film. Moreover, in addition to the process of peeling a board | substrate, the process of peeling an alignment film may be further included. Thereby, the single layer optical film of the present invention can be obtained. The film thickness of the optical film of the present invention is preferably 0.3 to 20 μm, more preferably 0.5 to 10 μm, and further preferably 0.5 to 5 μm. When the film thickness is within the above range, an optical film horizontally oriented in the smectic phase can be easily obtained.

  The optical film of the present invention is useful as a polarizing film having an excellent dichroic ratio when it contains a dichroic dye. Moreover, when it does not contain a dichroic dye, it is useful as a retardation film excellent in contrast.

  The optical film of the present invention obtained as described above can be used for various display devices. A display device is a device having a display element, and includes a light-emitting element or a light-emitting device as a light-emitting source. Examples of the display device include a liquid crystal display device, an organic electroluminescence (EL) display device, an inorganic electroluminescence (EL) display device, an electron emission display device (for example, a field emission display device (FED), a surface field emission display device (SED). )), Electronic paper (display device using electronic ink or electrophoretic element, plasma display device, projection display device (eg, display device having a grating light valve (GLV) display device, digital micromirror device (DMD)), Examples of the liquid crystal display device include a transmissive liquid crystal display device, a transflective liquid crystal display device, a reflective liquid crystal display device, a direct view liquid crystal display device, and a projection liquid crystal display device. The display device may be a display device that displays a two-dimensional image, or tertiary. Image may be a stereoscopic display apparatus for displaying.

  FIG. 1 is a schematic view showing a liquid crystal display device 10 of the present invention. The liquid crystal layer 17 is sandwiched between two substrates 14a and 14b.

A color filter 15 is disposed on the liquid crystal layer 17 side of the substrate 14a. The color filter 15 is disposed at a position facing the pixel electrode 22 across the liquid crystal layer 17, and the black matrix 20 is disposed at a position facing the boundary between the pixel electrodes. The transparent electrode 16 is disposed on the liquid crystal layer 17 side so as to cover the color filter 15 and the black matrix 20.
An overcoat layer may be provided between the color filter 15 and the transparent electrode 16.
Thin film transistors 21 and pixel electrodes 22 are regularly arranged on the liquid crystal layer 17 side of the substrate 14b. The pixel electrode 22 is disposed at a position facing the color filter 15 with the liquid crystal layer 17 interposed therebetween. An interlayer insulating film 18 having a connection hole (not shown) is disposed between the thin film transistor 21 and the pixel electrode 22.

Examples of the substrate 14a and the substrate 14b include a glass substrate and a plastic substrate.
When manufacturing the color filter 15 and the thin film transistor 21 formed on these substrates, a glass substrate is preferable when a process of heating to a high temperature is required.

  Examples of the thin film transistor 21 include a high-temperature polysilicon transistor formed on a quartz substrate, a low-temperature polysilicon transistor formed on a glass substrate, and an amorphous silicon transistor formed on a glass substrate or a plastic substrate. In order to reduce the size of the liquid crystal display device, a driver IC may be formed on the substrate 14b.

A liquid crystal layer 17 is disposed between the transparent electrode 16 and the pixel electrode 22. In the liquid crystal layer 17, spacers 23 are arranged in order to keep the distance between the substrate 14a and the substrate 14b constant.
Of the layers formed on the substrate 14a and the substrate 14b, an alignment film for aligning the liquid crystal in a desired direction may be disposed on the surface in contact with the liquid crystal layer 17.
Each member is laminated in the order of the substrate 14a, the color filter 15 and the black matrix 20, the transparent electrode 16, the liquid crystal layer 17, the pixel electrode 22, the interlayer insulating film 18 and the thin film transistor 21, and the substrate 14b.

On the outside of the substrate 14a and the substrate 14b with the liquid crystal layer 17 interposed therebetween, as optical films, polarizing films (for example, linear polarizers) 12a and 12b, retardation films (for example, quarter-wave plates and optical compensation films) 13a and 13b are stacked in this order. At least one selected from the group consisting of the polarizing films 12a and 12b and the retardation films 13a and 13b is the optical film of the present invention. By disposing the optical film of the present invention, the liquid crystal display device 10 can be provided with a function of converting incident light into linearly polarized light and circularly polarized light, and a function of optically compensating for a phase shift caused by liquid crystals. The retardation films 13 a and 13 b may not be arranged depending on the structure of the liquid crystal display device and the type of liquid crystal compound contained in the liquid crystal layer 17. An antireflection film 11 for preventing reflection of external light is disposed outside the polarizing film 12a. According to the optical film of the present invention, a thin display device can be achieved.
Laminate in which the optical film of the present invention, the alignment film, and the substrate used in producing the optical film are laminated as at least one selected from the group consisting of polarizing films 12a and 12b and retardation films 13a and 13b The body may be used.

  A backlight unit 19 that is a light source is disposed outside the polarizing film 12b. The backlight unit 19 includes a light source, a light guide, a reflection plate, a diffusion sheet, and a viewing angle adjustment sheet. Examples of the light source include electroluminescence, a cold cathode tube, a hot cathode tube, a light emitting diode (LED), a laser light source, and a mercury lamp. What is necessary is just to select the polarizer of this invention according to the characteristic of a light source.

  When the liquid crystal display device 10 of the present invention is a transmissive liquid crystal display device, the white light emitted from the light source in the backlight unit 19 enters the light guide, and the path is changed by the reflector and diffused by the diffusion sheet. Has been. The diffused light is adjusted to have a desired directivity by the viewing angle adjusting sheet, and then enters the polarizing film 12b from the backlight unit 19.

  Of the incident light that is non-polarized light, only one linearly polarized light is transmitted through the polarizing film 12b of the liquid crystal panel. This linearly polarized light is converted into circularly polarized light by the retardation film 13b, and sequentially passes through the substrate 14b, the pixel electrode 22 and the like and reaches the liquid crystal layer 17.

  Here, depending on the presence or absence of a potential difference between the pixel electrode 22 and the transparent electrode 16 facing the pixel electrode 22, the alignment state of the liquid crystal molecules contained in the liquid crystal layer 17 changes, and the luminance of the light emitted from the liquid crystal display device 10 is controlled. The When the liquid crystal layer 17 is in an orientation state in which the circularly polarized light converted by the retardation film 13b is transmitted as it is, the circularly polarized light is transmitted through the liquid crystal layer 17 and the transparent electrode 16, and light in a specific wavelength range is transmitted through the color filter. 15, the liquid crystal display device displays the color determined by the color filter brightest when it passes through the retardation film 13a and passes through the polarizing film 12a and the antireflection film 11.

  On the contrary, when the liquid crystal layer 17 is in an alignment state in which the circularly polarized light converted by the retardation film 13b is converted and transmitted, the light transmitted through the liquid crystal layer 17, the transparent electrode 16, and the color filter 15 is the retardation film. It is absorbed by 13a and the polarizer 12a. As a result, this pixel displays black. In the intermediate alignment state between these two states, the luminance of the light emitted from the liquid crystal display device 10 is also intermediate between the two, so that this pixel displays an intermediate color.

  In the case where the liquid crystal display device 10 of the present invention is a transflective liquid crystal display device, the pixel electrode 22 has a transmissive portion formed of a transparent material and a reflective portion formed of a material that reflects light. An image is displayed in the same manner as the above-described transmission type liquid crystal display device. On the other hand, in the reflection portion, external light enters the liquid crystal display device from the direction of the antireflection film 11, and circularly polarized light that has passed through the polarizing film 12 a and the retardation film 13 a passes through the liquid crystal layer 17 and is reflected by the pixel electrode 22. Used for display.

  FIG. 2 is a schematic diagram showing a liquid crystal display device 24 in which an optical film is arranged inside the substrate (the liquid crystal 17 side). In the liquid crystal display device 24, each member includes an antireflection film 11, a substrate 14a, a polarizing film 12a, a retardation film 13a, a color filter 15 and a black matrix 20, a transparent electrode 16, a liquid crystal layer 17, a pixel electrode 22, and an interlayer insulating film. 18, the thin film transistor 21, the retardation film 13b, the polarizing film 12b, the substrate 14b, and the backlight unit 19 are laminated in this order. At least one selected from the group consisting of the polarizing films 12a and 12b and the retardation films 13a and 13b is the optical film of the present invention. You may use the said laminated body. By disposing the optical film of the present invention, it is possible to provide the liquid crystal display device 24 with a function of converting incident light into linearly polarized light and circularly polarized light and a function of optically compensating for a phase shift caused by liquid crystal. The retardation films 13 a and 13 b may not be arranged depending on the structure of the liquid crystal display device and the type of liquid crystal compound contained in the liquid crystal layer 17.

  FIG. 3 is a schematic diagram showing an EL display device 30 of the present invention. In the EL display device 30, an organic functional layer 36 that is a light source and a cathode electrode 37 are laminated on a substrate 33 on which a pixel electrode 35 is formed. A retardation film 32 and a polarizing film 31 are disposed on the opposite side of the organic functional layer 36 across the substrate 33. At least one selected from the group consisting of the retardation film 32 and the polarizing film 31 is the optical film of the present invention. By applying a positive voltage to the pixel electrode 35 and a negative voltage to the cathode electrode 37 and applying a direct current between the pixel electrode 35 and the cathode electrode 37, the organic functional layer 36 emits light. The organic functional layer 36 that is a light emitting source includes an electron transport layer, a light emitting layer, a hole transport layer, and the like. Light emitted from the organic functional layer 36 passes through the pixel electrode 35, the interlayer insulating film 34, the substrate 33, the retardation film 32 and the polarizing film 31. Although the organic EL display device having the organic functional layer 36 will be described, the present invention may be applied to an inorganic EL display device having an inorganic functional layer.

  In order to manufacture the EL display device 30 of the present invention, first, the thin film transistor 40 is formed in a desired shape on the substrate 33. Then, an interlayer insulating film 34 is formed, and then a pixel electrode 35 is formed by sputtering and patterned. Thereafter, the organic functional layer 36 is laminated.

  Examples of the substrate 33 include a sapphire glass substrate, a quartz glass substrate, a soda glass substrate, a ceramic substrate such as alumina, a metal substrate such as copper, and a plastic substrate. A heat conductive film may be formed on the substrate. An example of the thermally conductive film is a diamond thin film (DLC or the like). When the pixel electrode 35 is a reflection type, light is emitted in the opposite direction to the substrate 33. Therefore, not only a transparent material but also a non-permeable material such as stainless steel can be used. A single substrate may be formed, or a plurality of substrates may be bonded together with an adhesive to form a laminated substrate. These substrates are not limited to plates but may be films.

As the thin film transistor 40, a normal polycrystalline silicon transistor may be used.
The thin film transistor 40 is provided at the end of the pixel electrode 35 and has a size of about 10 to 30 μm. The size of the pixel electrode 35 is about 20 μm × 20 μm to 300 μm × 300 μm.

  On the substrate 33, wiring electrodes of the thin film transistor 40 are provided. The wiring electrode has a low resistance and has a function of suppressing the resistance value by being electrically connected to the pixel electrode 35. Generally, the wiring electrode includes Al, Al and transition metals (except for Ti), Ti or One containing one or more of titanium nitride (TiN) is used.

An interlayer insulating film 34 is provided between the thin film transistor 40 and the pixel electrode 35. The interlayer insulating film 34 is formed by sputtering or vacuum deposition of an inorganic material such as silicon oxide such as SiO ₂ or silicon nitride, a silicon oxide layer formed by SOG (spin-on-glass), a photoresist, a polyimide. Any film may be used as long as it has insulating properties, such as a coating film of a resin material such as an acrylic resin.

  A rib 41 is formed on the interlayer insulating film 34. The rib 41 is disposed in the peripheral portion (between adjacent pixels) of the pixel electrode 35. Examples of the material of the rib 41 include acrylic resin and polyimide resin. The thickness of the rib 41 is preferably 1.0 μm or more and 3.5 μm, more preferably 1.5 μm or more and 2.5 μm or less.

  Next, an EL element including a pixel electrode 35 that is a transparent electrode, an organic functional layer 36 that is a light emission source, and a cathode electrode 37 will be described. Each of the organic functional layers 36 includes at least one hole transport layer and a light emitting layer. For example, the organic functional layer 36 sequentially includes an electron injection transport layer, a light emitting layer, a hole transport layer, and a hole injection layer.

Examples of the pixel electrode 35 include ITO (tin-doped indium oxide), IZO (zinc-doped indium oxide), IGZO, ZnO, SnO ₂ , and In ₂ O ₃ , and ITO and IZO are particularly preferable. The thickness of the pixel electrode 35 may be a certain thickness that can sufficiently inject holes, and is preferably about 10 to 500 nm.
The pixel electrode 35 can be formed by an evaporation method (preferably a sputtering method). The sputtering gas is not particularly limited, and an inert gas such as Ar, He, Ne, Kr, Xe, or a mixed gas thereof may be used.

As the constituent material of the cathode electrode 37, for example, K, Li, Na, Mg, La, Ce, Ca, Sr, Ba, Al, Ag, In, Sn, Zn, Zr or the like, or the stability is improved. It is preferable to use a two-component or three-component alloy system containing them. Examples of alloy systems include Ag · Mg (Ag: 1 to 20 at%), Al·Li (Li: 0.3 to 14 at%), In · Mg (Mg: 50 to 80 at%), Al · Ca (Ca: 5 to 20 at%) and the like are preferable.
The cathode electrode 37 is formed by vapor deposition, sputtering, or the like. The thickness of the cathode electrode 37 is 0.1 nm or more, preferably 1 to 500 nm or more.

The hole injection layer has a function of facilitating the injection of holes from the pixel electrode 35, and the hole transport layer has a function of transporting holes and a function of blocking electrons. Also called transport layer.
The thickness of the light emitting layer, the combined thickness of the hole injection layer and the hole transport layer, and the thickness of the electron injection transport layer are not particularly limited, and may vary depending on the formation method, but may be about 5 to 100 nm. preferable. Various organic compounds can be used for the hole injection layer and the hole transport layer. For the formation of the hole injecting and transporting layer, the light emitting layer, and the electron injecting and transporting layer, it is preferable to use a vacuum deposition method because a homogeneous thin film can be formed.

  Examples of the organic functional layer 36 that is a light emission source include those that use light emission (fluorescence) from singlet excitons, those that use light emission (phosphorescence) from triplet excitons, and those from singlet excitons. Including those using luminescence (fluorescence) and those using triplet excitons (phosphorescence), formed by organic matter, formed by inorganic matter, formed by organic matter A material including an inorganic material, a high molecular material, a low molecular material, a high molecular material and a low molecular material, or the like can be used. Note that the present invention is not limited to this, and EL display devices using various EL elements can be used.

  A desiccant 38 is disposed in the space between the cathode electrode 37 and the sealing lid 39. This is because the organic functional layer 36 is vulnerable to humidity. The desiccant 38 absorbs moisture and prevents the organic functional layer 36 from being deteriorated.

  The polarizing film 31 formed on the light incident surface or the light emitting surface of the EL display device 30 is not limited to a polarizing film that converts to linearly polarized light, and may be a polarizing film that converts to elliptically polarized light. The polarizing film 31 may be only the optical film of the present invention, or a polarizing film or a retardation film other than the optical film of the present invention may be used together.

FIG. 4 is a schematic view showing an EL display device 44 of the present invention. The EL display device 44 has a sealing structure using the thin-film sealing film 42 and can obtain emitted light from the opposite surface of the array substrate.
As the thin film sealing film 42, it is preferable to use a DLC film obtained by evaporating DLC (diamond-like carbon) on a film of an electrolytic capacitor. The DLC film has extremely poor moisture permeability and high moisture-proof performance. Further, a DLC film or the like may be directly deposited on the surface of the cathode electrode 37. Further, the thin film sealing film 42 may be formed by laminating a resin thin film and a metal thin film in multiple layers.

FIG. 6 is a schematic view showing a projection type liquid crystal display device of the present invention.
The polarizing film 142 and the polarizing film 143 of the present invention are used in, for example, a projection type liquid crystal display device (projector).
A light bundle emitted from a light source (for example, a high-pressure mercury lamp) 111 that is a light emission source first passes through a first lens array 112, a second lens array 113, a polarization conversion element 114, and a superimposing lens 115. The luminance is uniformed and polarized in the cross section of the anti-beam bundle.

  Specifically, the light bundle emitted from the light source 111 is divided into a number of minute light bundles by the first lens array 112 in which minute lenses 112a are formed in a matrix. The second lens array 113 and the superimposing lens 115 are provided so that each of the divided light bundles irradiates the entire three liquid crystal panels 140R, 140G, and 140B that are illumination targets. The liquid crystal panel incident side surface has almost uniform illuminance as a whole.

  The polarization conversion element 114 is configured by a polarization beam splitter array, and is disposed between the second lens array 113 and the superimposing lens 115. As a result, random polarized light from the light source is converted into polarized light having a specific polarization direction in advance, thereby reducing the amount of light loss in the incident side polarizer described later, thereby improving the screen brightness.

  The light whose luminance is uniformed and polarized as described above is sequentially converted into the red channel, the green channel, and the blue channel by the dichroic mirrors 121, 123, and 132 for separation into the three primary colors of RGB via the reflection mirror 122. These are separated and enter the liquid crystal panels 140R, 140G, and 140B, respectively.

  In the liquid crystal panels 140R, 140G, and 140B, the polarizer film 142 of the present invention is disposed on the incident side, and the polarizer film 143 of the present invention is disposed on the exit side.

  The polarizing film 142 and the polarizing film 143 arranged in each of the RGB optical paths are arranged so that the respective absorption axes are orthogonal to each other. Each of the liquid crystal panels 140R, 140G, and 140B arranged in each optical path has a function of converting the polarization state controlled for each pixel by an image signal into a light amount.

  The optical film of the present invention is useful as a polarizing film having excellent durability in any optical path of a blue channel, a green channel, and a red channel by selecting a type of dichroic dye suitable for the corresponding channel.

  An optical image created by transmitting incident light with different transmittance for each pixel according to the image data of the liquid crystal panels 140R, 140G, and 140B is synthesized by the cross dichroic prism 150, and is projected by the projection lens 170 to the screen 180. Is enlarged and projected.

  Electronic paper is displayed by molecules such as optical anisotropy and dye molecule orientation, displayed by particles such as electrophoresis, particle movement, particle rotation, and phase change, and one end of the film moves And the like, those displayed by molecular color development / phase change, those displayed by light absorption of molecules, and those displayed by self-emission by combining electrons and holes. More specifically, microcapsule type electrophoresis, horizontal movement type electrophoresis, vertical movement type electrophoresis, spherical twist ball, magnetic twist ball, cylindrical twist ball method, charged toner, electronic powder fluid, magnetophoretic type, magnetic thermosensitive Formula, electrowetting, light scattering (transparency / translucency change), cholesteric liquid crystal / photoconductive layer, cholesteric liquid crystal, bistable nematic liquid crystal, ferroelectric liquid crystal, dichroic dye / liquid crystal dispersion type, movable film, leuco dye And color erasing, photochromic, electrochromic, electrodeposition, flexible organic EL, and the like. The electronic paper may be used not only for personal use of text and images but also for advertisement display (signage) or the like. According to the optical film of the present invention, the thickness of the electronic paper can be reduced.

  As a stereoscopic display device, for example, a method of arranging different retardation films alternately like a micropole method has been proposed (Japanese Patent Laid-Open No. 2002-185983), but when the optical film of the present invention is used as a polarizing film, Since patterning is easy by printing, inkjet, photolithography, etc., the manufacturing process of the display device can be shortened, and a retardation film is not required.

  Hereinafter, the present invention will be described in more detail with reference to examples. Unless otherwise specified, “%” and “parts” in the examples are% by mass and parts by mass.

In the examples, the following polymerizable liquid crystal compounds were used.
Compound (1-6) (compound represented by the following formula (1-6))
Compound (1-6) was prepared according to Lub et al. Trav. Chim. It was synthesized by the method described in Pays-Bas, 115, 321-328 (1996).

(Measurement of phase transition temperature)
While heating the compound on the glass substrate on which the alignment film was formed, the phase transition temperature was confirmed by texture observation with a polarizing microscope (BX-51, manufactured by Olympus Corporation). The compound represented by the formula (1-6) exhibits a smectic A phase from a crystal phase at 95 ° C. at a temperature rise, phase transition to a nematic phase at 111 ° C., and a phase to an isotropic liquid phase at 113 ° C. Metastasized. When the temperature was lowered, it was confirmed that the phase transitioned to the nematic phase at 112 ° C., the phase transition to the smectic A phase at 110 ° C., and the phase transition to the smectic B phase at 94 ° C.

Compound (1-7) (compound represented by the following formula (1-7))
Compound (1-7) was prepared according to Lub et al. Recl. Trav. Chim. It was synthesized by the method described in Pays-Bas, 115, 321-328 (1996).

(Measurement of phase transition temperature)
The phase transition temperature was confirmed by texture observation with a polarizing microscope. The compound represented by the formula (1-7) exhibits a smectic A phase from a crystalline phase at 81 ° C. at a temperature rise, transitions to a nematic phase at 121 ° C., and a phase transition to an isotropic liquid phase at 137 ° C. did. When the temperature was lowered, it was confirmed that the phase transitioned to a nematic phase at 133 ° C., the phase transition to the smectic A phase at 118 ° C., and the phase transition to the smectic B phase at 78 ° C.

Example 1
(Adjustment of polymerizable liquid crystal composition)
The following components were mixed and stirred at 80 ° C. for 1 hour to obtain a polymerizable liquid crystal composition.
Polymerizable liquid crystal compound; Compound (1-6) 100 parts Dichroic dye; Azo dye (NKX2029; manufactured by Hayashibara Biochemical Laboratories) 2 parts Polymerization initiator; 2-dimethylamino-2-benzyl-1- (4- Morpholinophenyl) butan-1-one (Irgacure 369; manufactured by BASF Japan) 6 parts Polymerization initiator aid; Isopropylthioxanthone (produced by Nippon Sebel Hegner) 2 parts Leveling agent; Polyacrylate compound (BYK-361N; BYK-Chemie) 1.2 parts Solvent; 250 parts cyclopentanone

[Production of optical film]
A 2% by weight aqueous solution of polyvinyl alcohol (polyvinyl alcohol 1000 completely saponified type, manufactured by Wako Pure Chemical Industries, Ltd.) was applied on a glass substrate by a spin coating method, and dried to form an alignment film having a thickness of 89 nm. Subsequently, the surface of the obtained alignment film was rubbed. The rubbing process uses a semi-automatic rubbing apparatus (trade name: LQ-008, manufactured by Joyo Engineering Co., Ltd.) and a push-in amount of 0.15 mm using a cloth (trade name: YA-20-RW, manufactured by Yoshikawa Chemical Co., Ltd.). , Under the conditions of 500 rpm and 16.7 mm / s.
A polymerizable liquid crystal composition is applied onto the alignment film after rubbing by a spin coating method, dried by heating on a 120 ° C. hot plate for 3 minutes, and then rapidly cooled to 70 ° C. (temperature showing a smectic phase when the temperature is lowered). Thus, a coating film was obtained after drying. Using a UV irradiation device (SPOT CURE SP-7; manufactured by USHIO INC.), The coating film was produced by irradiating the coating film with ultraviolet rays having an exposure amount of 2400 mJ / cm ² (365 nm standard) after drying. An optical film was obtained.

[Dichroic ratio measurement]
Using a device in which a folder with a polarizer is set in an ultraviolet-visible spectrophotometer UV-3150 manufactured by Shimadzu Corporation, the absorbance in the transmission axis direction at the maximum absorption wavelength (A ¹ ) and the absorbance in the absorption axis direction (A ² ) are double-beamed. Measured by the method. The folder was provided with a mesh that cuts the light amount by 50% on the reference side. The ratio (A ² / A ¹ ) was calculated from the measured absorbance (A ¹ ) in the transmission axis direction and absorbance (A ² ) in the absorption axis direction to obtain a dichroic ratio. The results are shown in Table 2. It can be said that the higher the dichroic ratio, the more useful the polarizing film.

[Film thickness measurement]
About the obtained optical film, the film thickness was measured using the laser microscope (LEXT3000, Olympus company make). The results are shown in Table 2.

[Measurement of haze]
About the obtained optical film, the haze value was measured using the haze meter (HZ-2; Suga Test Instruments Co., Ltd. product). The results are shown in Table 2.

[Observation of liquid crystal phase]
About the liquid crystal phase which the obtained optical film has shown, it observed using the polarization microscope (BX-51, Olympus company make). Observation was performed between two polarizers whose transmission axes were orthogonal to each other so that the slow axis of the obtained polarizing film was in the direction of 45 ° with respect to the transmission axis.
When it was recognized that a horizontally oriented monodomain was formed, it was marked as “◯” in Table 2. The results are shown in Table 2.

[Observation of unevenness]
About the obtained optical film, it arrange | positioned so that an absorption axis might intersect orthogonally with an iodine-PVA polarizing plate (SRW842A; Sumitomo Chemical Co., Ltd. product), and visually observed on the direct type | mold backlight. In the case where no phase-separated unevenness was observed, it was marked as “◯” in Table 2. The results are shown in Table 2.

Examples 2-15, Reference Examples 1 and 2
A polymerizable liquid crystal composition was obtained in the same manner as in Example 1 except that the type of polymerizable liquid crystal compound and the type and amount of leveling agent were changed as shown in Table 1.

The following leveling agents were used in Table 1.
Polyacrylate compound (BYK-361N; manufactured by BYK-Chemie)
Polyacrylate compound (BYK-352; manufactured by BYK-Chemie)
Polyacrylate compound (BYK-354; manufactured by BYK-Chemie)
Polyacrylate compound (BYK-381; manufactured by BYK-Chemie)
Polyacrylate compound (BYK-392; manufactured by BYK-Chemie)
Fluorine-containing oligomer (Megafac F471; manufactured by DIC Corporation)
Fluorine-containing oligomer (Megafac F477; manufactured by DIC Corporation)

  The polymerizable liquid crystal compositions of Examples 2 to 15 and Reference Examples 1 and 2 obtained above were evaluated in the same manner as in Example 1. The results are shown in Table 2.

Example 16
(Adjustment of polymerizable liquid crystal composition)
The following components were mixed and stirred at 80 ° C. for 1 hour to obtain a polymerizable liquid crystal composition.
Polymerizable liquid crystal compound; Compound (1-6) 100 parts Polymerization initiator; 2-dimethylamino-2-benzyl-1- (4-morpholinophenyl) butan-1-one (Irgacure 369; manufactured by BASF Japan Ltd.) 6 parts Polymerization initiation aid: 2-isopropylthioxanthone (made by Nippon Sebel Hegner) 2 parts Leveling agent: polyacrylate compound (BYK-361N; made by BYK-Chemie) 1.2 parts Solvent: cyclopentanone 250 parts

[Production of optical film]
An optical film was obtained in the same manner as in Example 1.

[Observation of liquid crystal phase]
About the obtained optical film, when the liquid crystal phase was observed like Example 1, it was recognized that the horizontal alignment monodomain is formed.

[Measurement of film thickness]
About the obtained optical film, when the film thickness was measured like Example 1, it was 1.8 micrometers.

[Measurement of phase difference value]
About the obtained optical film, when the front phase difference value in wavelength 587.7nm was measured using the birefringence measuring apparatus (KOBRA-WR, Oji Scientific Instruments company make), it was 257 nm. In addition, since the glass substrate used for the base material has no birefringence, the front retardation value of the optical film produced on the glass substrate can be obtained by measuring the film with the glass substrate with a measuring machine. .

  According to the polymerizable liquid crystal composition of the present invention, an optical film in which a smectic phase oriented in the horizontal direction is formed can be easily obtained, and the dichroic ratio is high.

DESCRIPTION OF SYMBOLS 10 Liquid crystal display device 11 Antireflection film 12a, 12b Polarizing film 13a, 13b Phase difference film 14a, 14b Substrate 15 Color filter 16 Transparent electrode 17 Liquid crystal layer 18 Interlayer insulating film 19 Backlight unit 20 Black matrix 21 Thin film transistor 22 Pixel electrode 23 Spacer 24 liquid crystal display device 30 EL display device 31 polarizing film 32 retardation film 33 substrate 34 interlayer insulating film 35 pixel electrode 36 light emitting layer 37 cathode electrode 38 desiccant 39 sealing lid 40 thin film transistor 41 rib 42 thin film sealing film 44 EL display device 111 Light source 112 First lens array 112a Lens 113 Second lens array 114 Polarization conversion element 115 Superimposing lenses 121, 123, 132 Dichroic mirror 122 Reflection mirrors 140R, 140G, 140 B Liquid crystal panels 142 and 143 Polarizing film 150 Cross dichroic prism 170 Projection lens 180 Screen

Claims (9)

A polymerizable liquid crystal compound exhibiting a smectic phase, a leveling agent and a solvent,
The leveling agent is at least one selected from the group consisting of a leveling agent mainly composed of a polyacrylate compound and a leveling agent mainly composed of a fluorine atom-containing compound,
A polymerizable liquid crystal composition, wherein the content of the leveling agent is 0.3 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the polymerizable liquid crystal compound.   2. The polymerizable liquid crystal compound according to claim 1, wherein the polymerizable liquid crystal compound is a polymerizable liquid crystal compound having a temperature exhibiting a nematic phase within a temperature range between a temperature exhibiting a smectic phase and a temperature exhibiting an isotropic phase. Composition.   The polymerizable liquid crystal composition according to claim 1, further comprising a dichroic dye.   An optical film obtained by polymerizing the polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition according to claim 1. The manufacturing method of an optical film including the process of (1)-(3).
(1) Step (2) of applying the polymerizable liquid crystal composition according to any one of claims 1 to 3 on a substrate to obtain a coating film (2) A liquid crystal phase is formed on the coating film obtained in (1) Steps for converting into a film (3) Steps for obtaining an optical film by polymerizing the polymerizable liquid crystal compound contained in the film formed by the liquid crystal phase obtained in (2)   The production method according to claim 5, wherein the liquid crystal phase is a smectic phase.   (2) heating the coating film obtained in (1) above the temperature at which the polymerizable liquid crystal compound contained in the coating film exhibits a nematic phase, and then the polymerizable liquid crystal compound exhibits a smectic phase. The manufacturing method according to claim 5 or 6, wherein the coating film is cooled to a temperature to convert it into a film in which a smectic phase is formed.   The optical film obtained by the manufacturing method in any one of Claims 5-7.   A display device comprising the optical film according to claim 4.

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