CN103048721B - Polarization film, circular polarization light board and their manufacture method - Google Patents

Abstract

To provide a polarizing film and the like which are thin films and have high polarizing performance, which can be used in members for display devices. Provided are a polarizing film formed of a composition, a liquid crystal display device provided with the polarizing film, etc. At least one nitrogen-based dye, and a polymerizable smectic liquid crystal compound. [In formula (1), Ar ₂ is selected from the groups shown below. The aforementioned polymerizable smectic liquid crystal compound is preferably a compound exhibiting a higher smectic liquid crystal state.

Description

Polarizing film, circular polarizing plate and their manufacturing method

technical field

The present invention relates to a polarizing film, a circular polarizing plate, their manufacturing methods, and the like.

Background technique

As a polarizer used in a liquid crystal display device, a film made of iodine-dyed polyvinyl alcohol is generally used. On the other hand, along with the recent strong demand for thinner liquid crystal display devices, polarizers are also required to be further thinned. As a thin polarizing film included in a thin polarizer, for example, Patent Document 1 describes a film formed of a composition containing a polymerizable nematic liquid crystal compound and a dichroic dye. In addition, regarding this dichroic dye, for example, Patent Document 2 describes it as a specific polyazo-based dye for forming a polarizing film by vapor deposition.

prior art literature

patent documents

[Patent Document 1] Japanese Patent Application Publication No. 2007-510946

[Patent Document 2] Japanese Patent Laid-Open No. 8-278409

Contents of the invention

Polarizing films that are required to be further thinned are expected to have high polarizing performance, especially a high dichroic ratio.

The present invention includes the following inventions.

[1] A polarizing film comprising at least one polyazo pigment represented by the following general formula (1) that absorbs in the wavelength range of 400 to 800 nm, and

Compositions of polymerizable smectic liquid crystal compounds are formed.

[In formula (1),

n is 1 or 2.

Ar ₁ and Ar ₃ each independently represent a group selected from the groups shown below.

Ar ₂ represents a group selected from the groups shown below.

A1 and _A2 each independently represent _a group selected from the groups shown below.

(m is an integer of 0 to 10, when there are 2 m in the same group, these 2 m are the same or different from each other.)]

[2] The polarizing film according to the above [1], which has a thickness of not less than 1 μm and not more than 10 μm.

[3] The polarizing film according to the above [1] or [2], which has a Bragg peak in X-ray diffraction measurement.

[4] A polarizer comprising the polarizing film according to any one of the above [1] to [3], an alignment film, and a transparent substrate in this order.

[5] A method for manufacturing a polarizer, the polarizer sequentially comprising the polarizing film, an alignment film, and a transparent substrate according to any one of the above [1] to [3], the manufacturing method comprising the following steps:

preparing a laminate comprising the alignment film on the transparent substrate,

On the alignment film of the laminate, a polyazo pigment represented by the above-mentioned general formula (1) containing a polymerizable smectic liquid crystal compound and absorbing in a wavelength range of 400 to 800 nm, and a polymerization initiator are formed. agent and solvent film process,

a step of removing said solvent from said membrane,

a step of making the polymerizable smectic liquid crystal compound contained in the film from which the solvent has been removed into a smectic liquid crystal state,

A step of forming a polarizing film on the alignment film by polymerizing the polymerizable smectic liquid crystal compound while maintaining the state of the smectic liquid crystal.

[6] A liquid crystal display device comprising the polarizing film according to any one of the above [1] to [3].

[7] A circular polarizing plate having the polarizing film and the λ/4 layer described in any one of the above [1] to [3], and satisfying the following requirements (A1) and (A2):

(A1) The angle formed by the absorption axis of the polarizing film and the slow axis of the λ/4 layer is approximately 45°;

(A2) The front retardation value of the λ/4 layer measured under light having a wavelength of 550 nm is in the range of 100 to 150 nm.

[8] A circular polarizing plate, which sequentially has the polarizing film described in any one of the above [1] to [3], a λ/2 layer, and a λ/4 layer, and satisfies the following (B1), (B2) , (B3) and (B4) requirements:

(B1) The angle formed by the absorption axis of the polarizing film and the slow axis of the λ/2 layer is approximately 15°;

(B2) The angle formed by the slow axis of the λ/2 layer and the slow axis of the λ/4 layer is approximately 60°;

(B3) The front retardation value of the λ/4 layer measured under light with a wavelength of 550 nm for the λ/2 layer is in the range of 200 to 300 nm;

(B4) The front-side retardation value of the λ/4 layer measured under light having a wavelength of 550 nm is in the range of 100 to 150 nm.

[9] An organic EL display device comprising the circularly polarizing plate and an organic EL element according to the above [7] or [8].

The effect of the invention

According to the present invention, a thin polarizing film having a high dichroic ratio, a polarizer including the polarizing film, a liquid crystal display device, a circularly polarizing plate, and an organic EL display device can be provided.

Description of drawings

[FIG. 1] A schematic cross-sectional view of main parts of the continuous production method (roll-to-roll format) of the present polarizing film.

[ Fig. 2 ] A schematic cross-sectional view showing a cross-sectional configuration of a liquid crystal display device using a polarizer including the present polarizing film.

[FIG. 3] An enlarged schematic cross-sectional view of the stacking sequence of polarizers including this polarizing film installed in a liquid crystal display device.

[FIG. 4] An enlarged schematic cross-sectional view of the stacking sequence of polarizers including this polarizing film installed in a liquid crystal display device.

[ Fig. 5 ] A schematic cross-sectional view showing a cross-sectional configuration of a liquid crystal display device (in-cell type) using a polarizer including the present polarizing film.

[FIG. 6] A schematic cross-sectional view of the simplest configuration of a circularly polarizing plate including the present polarizing film.

[ Fig. 7 ] A schematic cross-sectional view of main parts of a continuous manufacturing method of a circularly polarizing plate including the present polarizing film.

[ Fig. 8 ] A schematic cross-sectional view showing a cross-sectional configuration of an EL display device using a circularly polarizing plate including the present polarizing film.

[FIG. 9] An enlarged schematic cross-sectional view of the lamination sequence of circularly polarizing plates including this polarizing film installed in an EL display device.

[ Fig. 10 ] A schematic cross-sectional view showing a cross-sectional configuration of an EL display device using a circularly polarizing plate including the present polarizing film.

[ Fig. 11 ] A schematic cross-sectional view showing a cross-sectional structure of a projection-type liquid crystal display device using a polarizer including the present polarizing film.

Symbol Description

1 transparent substrate

2 Photo-alignment film

3 pieces of polarizing film

100 polarizer

101 1st layer laminate

102 2nd layer laminate

103 3rd layer laminate

210 1st Roller 210A Core

220 Second drum 220A Core

211A, 211B coating device

212A, 212B drying oven

213A polarized light UV irradiation device

213B Light irradiation device

300 auxiliary roller

10 Liquid crystal display device

12a, 12b polarizing film

13a, 13b retardation film

14a, 14b Substrate

15 color filters

16 transparent electrodes

17 Liquid crystal layer

18 Interlayer insulating film

19 backlight module

20 black matrix

21 thin film transistor

22 pixel electrodes

23 Spacers

24 Liquid crystal display device

30 EL display device

31 polarizing film

32 retardation film

33 Substrate

34 Interlayer insulating film

35 pixel electrodes

36 luminous layer

37 Cathode electrode

38 desiccant

39 Package cover

40 thin film transistors

41 Ribs

42 film sealing film

44 EL display device

111 light source

112 1st lens array

112a lens

113 Second lens array

114 polarized light conversion element

115 compound lens

121, 123, 132 dichroic mirrors

122 mirrors

140R, 140G, 140B LCD panel

142, 143 polarizer

150 cross dichroic prism

170 projection lens

180 projection screen

detailed description

The polarizing film of the present invention (hereinafter referred to as "this polarizing film" as the case may be) is characterized in that it consists of a composition containing a polyazo dye represented by the above formula (1) and a polymerizable smectic liquid crystal compound ( Hereinafter, it may be referred to as "the composition for forming a polarizing film") depending on the case. This polarizing film is not only suitable for liquid crystal display devices, as described later, by using this polarizing film, it is also possible to manufacture polarizers suitable for organic EL display devices (hereinafter referred to as "this polarizer") or Circularly polarizing plate (hereinafter referred to as "the present circularly polarizing plate" as the case may be). Hereinafter, the present polarizing film and its manufacturing method, the present polarizer and its manufacturing method, and the present circular polarizing plate and its manufacturing method will be described with reference to the drawings as necessary. In addition, the dimensions of the drawings in this specification are only for ease of viewing.

<Polyazo dyes>

The polyazo pigment used in the manufacture of this polarizing film (hereinafter referred to as "azo pigment (1)" as the case may be) is shown in formula (1), and the azo pigment (1) has The range has absorption.

The stereoisomerism of the azobenzene moiety of the azo dye (1) is preferably trans.

Examples of the azo dye (1) include compounds represented by formulas (1-1) to (1-27), respectively.

Among the specific examples of the above azo-based pigments (1), it is more preferred to use formula (1-2), formula (1-5), formula (1-6), formula (1-8), formula (1) respectively -10), formula (1-12), formula (1-13), formula (1-15), formula (1-16), formula (1-19), formula (1-20), formula (1- 21), the compound represented by formula (1-22), formula (1-23), formula (1-24) and formula (1-26), particularly preferably respectively by formula (1-2), formula (1-5 ), formula (1-8), formula (1-10), formula (1-15), formula (1-21), formula (1-22) and the compound represented by formula (1-26).

The content of the azo-based dye (1) in the composition for forming a polarizing film is expressed as the content relative to 100 parts by mass of the polymerizable smectic liquid crystal compound described later, and is preferably 50 parts by mass or less, more preferably 0.1 parts by mass The above is 20 mass parts or less, more preferably 0.1 mass parts or more and 10 mass parts or less. When it is within the above range, there is an advantage that the orientation of the polymerizable smectic liquid crystal compound is not disturbed when the polarizing film is formed. The azo dye (1) contained in the composition for polarizing film formation may be 1 type, and may be 2 or more types. When there are 2 or more types of azo dyes (1) contained in the composition for polarizing film formation, the total amount should just be in the said range.

<Polymerizable Smectic Liquid Crystal Compound>

The polymerizable smectic liquid crystal compound contained in the above-mentioned composition for forming a polarizing film refers to a compound that has a polymerizable group and exhibits a smectic liquid crystal state. The polymerizable group refers to a group that participates in the polymerization reaction of the polymerizable smectic liquid crystal compound.

The liquid crystal state exhibited by the polymerizable smectic liquid crystal compound is preferably a higher order smectic phase. The advanced smectic phase here refers to smectic B phase, smectic D phase, smectic E phase, smectic F phase, smectic G phase, smectic H phase, smectic I phase, smectic J phase, smectic The crystal K phase and the smectic L phase, among them, the smectic B phase, the smectic F phase, and the smectic I phase are more preferable. According to the liquid crystal state exhibited by the polymerizable smectic liquid crystal compound, this polarizing film having a high degree of alignment order can be obtained. In addition, this polarizing film having such a high degree of orientation order can obtain Bragg peaks in X-ray diffraction measurement.

The Bragg peak refers to the peak of the periodic structure of the plane due to molecular orientation. Depending on the composition for forming a polarizing film, the periodic interval can be obtained as The polarizing film.

Preferable polymerizable smectic liquid crystal compounds include, for example, compounds represented by formula (2) (hereinafter referred to as "compound (2) as the case may be").

U ¹ -V ¹ -W ¹ -X ¹ -Y ¹ -X ² -Y ² -X ³ -W ² -V ² -U ² (2)

[In formula (2),

X ¹ , X ² and X ³ each independently represent an optionally substituted p-phenylene group or an optionally substituted 1,4-cyclohexylene group. Among them, at least one of X ¹ , X ² and X ³ is a p-phenylene group which may have a substituent.

Y ¹ and Y ² each independently represent -CH ₂ CH ₂ -, -CH ₂ O-, -COO-, -OCOO-, single bond, -N=N-, -CR ^a =CR ^b -, -C≡ C- or -CR ^a =N-. 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 alkylene group having 1 to 20 carbon atoms, and -CH ₂ - constituting the alkylene group may be replaced by -O-, -S- or -NH-. ]

Preferably, at least two of X ¹ , X ² and X ³ are p-phenylene groups which may have substituents.

Preferably, p-phenylene is unsubstituted. Preferably, the 1,4-cyclohexylene is trans-1,4-cyclohexylene, and more preferably, the trans-1,4-cyclohexylene is also unsubstituted.

Examples of substituents that p-phenylene or 1,4-cyclohexylene has include alkyl groups having 1 to 4 carbon atoms such as methyl, ethyl, and butyl groups; cyano groups; and halogen atoms. In addition, -CH ₂ - constituting the 1,4-cyclohexylene group may be replaced by -O-, -S- or -NR-. R is an alkyl group or phenyl group having 1 to 6 carbon atoms.

Preferably Y ¹ is -CH ₂ CH ₂ -, -COO- or a single bond, and Y ² is preferably -CH ₂ CH ₂ - or -CH ₂ O-.

U ² is a polymerizable group. U ¹ is a hydrogen atom or a polymerizable group, preferably a polymerizable group. Preferably, ^{both U1} and U2 are polymerizable groups. The polymerizable group is preferably a photopolymerizable group. The photopolymerizable group refers to a group capable of participating in a polymerization reaction by an active radical generated by a photopolymerization initiator described later, an acid, or the like. Using a polymerizable smectic liquid crystal compound having a photopolymerizable group is advantageous in that the polymerizable smectic liquid crystal compound can be polymerized at a lower temperature.

U ¹ and U ² polymerizable groups may be different from each other, but are preferably the same type of group.

Examples of polymerizable groups include vinyl, vinyloxy, 1-chlorovinyl, isopropenyl, 4-vinylphenyl, acryloyloxy, methacryloyloxy, oxiranyl, oxygen Heterobutyl, etc. Among them, acryloyloxy, methacryloyloxy, vinyloxy, oxiranyl and oxetanyl are preferred, and acryloyloxy is more preferred.

^The alkylene groups ^of V1 and V2 include methylene, ethylene, 1,3-propylene, 1,3-butylene, 1,4-butylene, 1,5-pentylene, 1,6-hexylene, 1,7-heptylene, 1,8-octylene, 1,10-decylene, 1,14-tetradecylene and 1,20-eicosylene Wait. V ¹ and V ² are preferably an alkylene group having 2 to 12 carbon atoms, more preferably an alkylene group having 6 to 12 carbon atoms.

As the substituent which the alkylene group has, a cyano group, a halogen atom, etc. are mentioned. The alkylene group is preferably unsubstituted, more preferably an unsubstituted straight-chain alkylene group.

W ¹ and W ² are each independently preferably a single bond or -O-.

Examples of the compound (2) include compounds represented by the formulas (2-1) to (2-24), respectively. When a specific example of the related compound (2) has a 1,4-cyclohexylene group, it is preferable that the 1,4-cyclohexylene group is a trans form.

The polymerizable smectic liquid crystal compound can be used in the composition for polarizing film formation individually or in mixture of 2 or more types.

When a polymerizable smectic liquid crystal compound is used in a composition for forming a polarizing film, the phase transition temperature of the polymerizable smectic liquid crystal compound is obtained in advance, and the polarizing film is adjusted at a temperature lower than the phase transition temperature. Components other than the polymerizable smectic liquid crystal compound of the forming composition are polymerized by polymerizing the polymerizable smectic liquid crystal compound. Examples of components capable of controlling such a polymerization temperature include a polymerization initiator, a sensitizer, a polymerization inhibitor, and the like described later. The polymerization temperature of the polymerizable smectic liquid crystal compound can be controlled by appropriately adjusting the types and amounts of these compounds. In addition, when two or more polymerizable smectic liquid crystal compounds are used in the composition for forming a polarizing film, after obtaining the phase transition temperature of the mixture of the two or more polymerizable smectic liquid crystal compounds, the same as above To control the polymerization temperature.

Among the exemplified compounds (2), preferably selected from formula (2-2), formula (2-3), formula (2-4), formula (2-6), formula (2-7), formula (2-8), formula (2-13), formula (2-14), formula (2-15) and formula (2-24).

The polymerizable smectic liquid crystal compound is preferably capable of maintaining the high-order smectic liquid crystal state easily at a temperature lower than the phase transition temperature by mixing or interacting with a polymerization initiator used at the same time. In case, the compound that makes it polymerize. More specifically, the polymerizable smectic liquid crystal compound is preferably a compound capable of polymerizing while maintaining a high-order smectic liquid crystal state at a temperature of 70° C. or lower, preferably 60° C. or lower, by interacting with a polymerization initiator. .

The polymerizable smectic liquid crystal compound contained in the above-mentioned composition for forming a polarizing film may be a single type or a plurality of types, but preferably a plurality of types.

The content ratio of the polymerizable smectic liquid crystal compound in the composition for forming a polarizing film is preferably 70 to 99.9% by mass, more preferably 90 to 99.9% by mass based on the solid content of the composition for forming a polarizing film. When the content ratio of the polymerizable smectic liquid crystal compound is within the above range, the orientation of the polymerizable smectic liquid crystal compound tends to be high. Here, solid content means the total amount of the component which removed the volatile components, such as a solvent, from this composition for polarizing film formation. In addition, when a plurality of polymerizable smectic liquid crystal compounds are contained in the composition for forming a polarizing film, the total content ratio may be within the above-mentioned range.

<solvent>

A solvent may also be contained in the composition for polarizing film formation. Generally, since the viscosity of a polymeric smectic liquid crystal compound is high, coating can be made easy by containing a solvent, and as a result, the formation of a polarizing film is often easy. The solvent is preferably a solvent capable of completely dissolving the polymerizable smectic liquid crystal compound and the azo dye (1). Moreover, it is preferable that it is an inert solvent with respect to the polymerization reaction of the composition for polarizing film formation.

Solvents include alcohol solvents such as methanol, ethanol, ethylene glycol, isopropanol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, and propylene glycol monomethyl ether; Ester solvents such as glycol methyl ether acetate, γ-butyrolactone or propylene glycol methyl ether acetate and ethyl lactate; acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone and methyl isobutyl ketone and other ketone solvents; pentane, hexane and heptane and other aliphatic hydrocarbon solvents; toluene and xylene and other aromatic hydrocarbon solvents, acetonitrile and other nitrile solvents; tetrahydrofuran and dimethoxyethane and other ethers Solvents; chlorine-containing solvents such as chloroform and chlorobenzene, etc. These solvents may be used alone or in combination.

It is preferable that content of a solvent is 50-98 mass % with respect to the total amount of the said composition for polarizing film formation. In other words, it is preferable that the solid content in the composition for polarizing film formation is 2-50 mass %. When the solid content is 2% by mass or more, it tends to be easier to obtain the thin polarizing film which is one of the objects of the present invention. On the other hand, when the solid content is at most 50% by mass, the viscosity of the composition for forming a polarizing film becomes low, and the thickness of the polarizing film becomes substantially uniform, which tends to make the polarizing film less likely to be uneven. In addition, the relevant solid content can be determined by the thickness which can form the polarizing film mentioned later.

<Polymerization Auxiliary>

It is preferable that the said composition for polarizing film formation contains a polymerization initiator. The polymerization initiator is a compound capable of initiating the polymerization reaction of the polymerizable smectic liquid crystal compound, and is preferably a photopolymerization initiator in terms of initiating the polymerization reaction at a lower temperature. Specifically, a compound capable of generating active radicals or acids by the action of light is used as a photopolymerization initiator. Among the photopolymerization initiators, those that generate radicals by the action of light are more preferable.

Examples of the above-mentioned polymerization initiators include benzoin compounds, benzophenone compounds, phenalkone compounds, acylphosphine oxide compounds, triazine compounds, iodonium salts, and sulfonium salts.

Specific examples of the polymerization initiator are listed below.

Examples of the benzoin compound include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether.

Benzophenone compounds can be listed, for example, benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyl diphenyl sulfide, 3, 3',4,4'-Tetra(tert-butylperoxycarbonyl)benzophenone and 2,4,6-trimethylbenzophenone, etc.

Phenyl ketone compounds include, for example, diethoxyacetophenone, 2-methyl-2-morpholino-1-(4-methylthiophenyl)-1-propanone, 2-benzyl- 2-Dimethylamino-1-(4-morpholinephenyl)-1-butanone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1,2-diphenyl-2 , 2-dimethoxy-1-ethanone, 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]-1-propanone, 1-hydroxycyclohexylphenyl Ketones and oligomers of 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]-1-propanone, etc.

Examples of the acylphosphine oxide compound include 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

Triazine compounds include, for example, 2,4-bis(trichloromethyl)-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4-bis(trichloromethyl) )-6-(4-methoxynaphthyl)-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)vinyl]-1,3,5-triazine, 2, 4-bis(trichloromethyl)-6-[2-(furan-2-yl)vinyl]-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[ 2-(4-diethylamino-2-methylphenyl)vinyl]-1,3,5-triazine and 2,4-bis(trichloromethyl)-6-[2-(3, 4-dimethoxyphenyl)vinyl]-1,3,5-triazine, etc.

As the polymerization initiator, those readily available on the market can be used. Examples of commercially available polymerization initiators include “Irgacure (Irgacure) 907”, “Irgacure 184”, “Irgacure 651”, “Irgacure 819”, “Irgacure 250”, and “Irgacure 369” (Chiba Japan Co., Ltd.); "セイクオールBZ", "セイクオルZ", "セイクオルBEE" (Seiko Chemical Co., Ltd.); "Kayacure BP100" (Kayacure Co., Ltd.); 6992" (manufactured by Dou Corporation); "Adeka Optoma-SP-152", "Adeka Optoma-SP-170" ((Co., Ltd.) ADEKA); "TAZ-A", "TAZ-PP" (Nippon Shiibeluヘグナ Corporation); and " TAZ-104" (Sanwa Chemical Corporation), etc.

When the above-mentioned composition for forming a polarizing film contains a polymerization initiator, its content can be appropriately adjusted according to the type and amount of the polymerizable smectic liquid crystal compound contained in the composition for forming a polarizing film, but for example The content of the polymerization initiator is preferably in the range of 0.1 to 30 parts by mass, more preferably in the range of 0.5 to 10 parts by mass, and still more preferably in the range of 0.5 to 8 parts by mass, based on 100 parts by mass of the total amount of the polymerizable smectic liquid crystal compound. When the content of the polymerizable initiator is within this range, since the polymerizable smectic liquid crystal compound can be polymerized without disturbing the orientation of the polymerizable smectic liquid crystal compound, it is possible to maintain high-order smectic liquid crystal compounds in the polymerizable smectic liquid crystal compound. Polymerization is carried out in the liquid crystal state.

When the above composition for forming a polarizing film contains a polymerization initiator, a sensitizer may also be contained in the composition for forming a polarizing film. The sensitizer is preferably a photosensitizer. Such sensitizers include, for example, xanthone compounds such as xanthone and thioxanthone (such as 2,4-diethylthioxanthone, 2-isopropylthioxanthone, etc.); Anthracene compounds such as oxy-anthracene (for example, dibutoxyanthracene, etc.); phenothiazine, rubrene, etc.

When the composition for forming a polarizing film contains a polymerization initiator and a sensitizer, the polymerization reaction of the polymerizable smectic liquid crystal compound contained in the composition for forming a polarizing film can be further accelerated. Although the usage amount of the related sensitizer can be appropriately adjusted according to the type and amount of the polymerization initiator and the polymerizable smectic liquid crystal compound used in combination, for example, 100% by mass relative to the total amount of the polymerizable smectic liquid crystal compound parts, preferably in the range of 0.1 to 30 parts by mass, more preferably in the range of 0.5 to 10 parts by mass, and still more preferably in the range of 0.5 to 8 parts by mass.

Although it has been explained that the polymerization reaction of the polymerizable smectic liquid crystal compound can be accelerated by making the above-mentioned polarizing film-forming composition contain a sensitizer, in order to make the polymerization reaction stably proceed, the polarizing film-forming composition A polymerization inhibitor may also be contained in a moderate amount. By containing a polymerization inhibitor, the progress degree of the polymerization reaction of a polymerizable smectic liquid crystal compound can be controlled.

The above-mentioned polymerization inhibitors include, for example, hydroquinone, alkoxy hydroquinone, alkoxy catechol (for example, butyl catechol, etc.), pyrogallol, 2,2,6 , 6-tetramethyl-1-piperidinyloxy radical and other free radical scavengers; thiophenols; β-naphthylamines and β-naphthols, etc.

When the above-mentioned composition for forming a polarizing film contains a polymerization inhibitor, although its content can be appropriately adjusted according to the type and amount of the polymerizable smectic liquid crystal compound used, and the amount of the sensitizer used, etc., for example The content of the polymerization inhibitor is preferably in the range of 0.1 to 30 parts by mass, more preferably in the range of 0.5 to 10 parts by mass, and still more preferably in the range of 0.5 to 8 parts by mass, based on 100 parts by mass of the polymerizable smectic liquid crystal compound. When the content of the polymerization inhibitor is within this range, because it can be polymerized without disturbing the orientation of the polymerizable smectic liquid crystal compound contained in the composition for forming a polarizing film, the polymerizability is close to The crystalline liquid crystal compound can further be polymerized while maintaining the high-order smectic liquid crystal state well.

<Leveling agent>

It is preferable that the said composition for polarizing film formation contains a leveling agent. The leveling agent has the function of adjusting the fluidity of the composition for forming a polarizing film and making the coating film obtained by applying the composition for forming a polarizing film smoother, and examples thereof include surfactants and the like. This leveling agent is more preferably at least 1 sort(s) selected from the leveling agent mainly composed of a polyacrylate compound, and the leveling agent mainly composed of a fluorine atom-containing compound.

The leveling agents mainly composed of polyacrylate compounds include "BYK-350", "BYK-352", "BYK-353", "BYK-354", "BYK-355", "BYK-358N" , "BYK-361N", "BYK-380", "BYK-381" and "BYK-392" [BYK Chemie], etc.

Leveling agents mainly composed of fluorine-containing compounds include "Mega-fac (Megafac) R-08", same "R-30", same "R-90", same "F-410", same " F-411", same as "F-443", same as "F-445", same as "F-470", same as "F-471", same as "F-477", same as "F-479", same as "F -482" and same as "F-483" [DIC (strain)]; "Surflon (surflon) S-381", same as "S-382", same as "S-383", same as "S-393", Same as "SC-101", "SC-105", "KH-40" and "SA-100" [AGC Seimi Chemical Co., Ltd.]; "E1830", "E5844" [(Co.) Daikin Fine Chemical (ダイキンFain Chemical) Research Institute]; "Eftop EF301", the same "EF303", the same "EF351" and the same "EF352" [Mitsubishi Material Electronics Chemicals Co., Ltd.], etc.

When the above composition for forming a polarizing film contains a leveling agent, its content is preferably in the range of 0.3 to 5 parts by mass, more preferably 0.5 to 3 parts by mass, based on 100 parts by mass of the polymerizable smectic liquid crystal compound. below the range. When the content of the leveling agent is within the above range, it is easy to horizontally align the polymerizable smectic liquid crystal compound, and it tends to make the formed polarizing film smoother. When content of a leveling agent with respect to a polymerizable smectic liquid crystal compound exceeds the said range, it exists in the tendency which becomes easy to generate|occur|produce unevenness in the polarizing film obtained. Moreover, this composition for polarizing film formation may contain 2 or more types of leveling agents.

<Formation method of this polarizing film>

Next, the method of forming this polarizing film from the said composition for polarizing film formation is demonstrated. In a related method, the present polarizing film is preferably formed by coating the composition for forming a polarizing film on a substrate, preferably a transparent substrate.

<Transparent substrate>

The above-mentioned transparent substrate refers to a substrate having transparency capable of transmitting light, especially visible light. The transparency refers to the characteristic that the transmittance is more than 80% for the light in the wavelength range of 380-780nm. Specifically, examples of the transparent substrate include glass substrates, or plastic translucent sheets and translucent films. In addition, plastics constituting the light-transmitting sheet or film include, for example, polyolefins such as polyethylene, polypropylene, and norbornene-based polymers; cyclic olefin-based resins; polyvinyl alcohol; polyterephthalic acid Ethylene glycol esters; polymethacrylates; polyacrylates; cellulose esters such as cellulose triacetate, cellulose diacetate, and cellulose acetate propionate; polyethylene naphthalate; polycarbonate ; Polysulfone; polyethersulfone; polyether ketone; polyphenylene sulfide and polyphenylene ether and other plastics. Among the specific examples of the above-mentioned transparent base material, the plastic light-transmitting film and polymer film are preferable as the plastic light-transmitting sheet and the light-transmitting film. Among the polymer films, those made of cellulose ester, cyclic olefin resin, polyethylene terephthalate, or polymethacrylate are particularly preferable because they are easily purchased from the market and have excellent transparency. Molecular membrane. When the polarizing film is manufactured using the transparent substrate, a support substrate or the like can be attached to the transparent substrate because it is less prone to damage such as cracking during transportation and storage, and is easy to handle. In addition, as described later, when a circularly polarizing plate is produced from this polarizing film, retardation may be imparted to the transparent substrate. In this case, a polymer film is prepared as a transparent substrate, and the polymer film is provided with a retardation by stretching the polymer film. After the retardation film is made, the retardation film is It can be used as a transparent substrate. Also, a method for imparting retardation to a transparent substrate (polymer film) will be described.

Among the above-mentioned polymer films, when imparting phase difference, a film composed of cellulose ester or cyclic olefin resin (cellulose ester film, cyclic olefin resin film) is preferable because it is easy to control the value of the phase difference. ). These two types of polymer films will be described in detail below.

As for the cellulose ester constituting the cellulose ester film, at least a part of the hydroxyl groups contained in the cellulose may be esterified with acetate. Cellulose ester films composed of such cellulose esters are readily available on the market. Commercially available cellulose triacetate films include, for example, "Fujitaku Film" (Fuji Photo Film Co., Ltd.); "KC8UX2M", "KC8UY" and "KC4UY" (Konika Minolta Opto Co., Ltd.). Such a commercially available cellulose triacetate film can be used as a transparent substrate after imparting retardation property as it is or if necessary. In addition, the surface of the prepared transparent substrate can be used as the transparent substrate 1 after surface treatment such as anti-glare treatment, hard coat treatment, antistatic treatment and anti-reflection treatment.

When imparting retardation to a polymer film, methods such as stretching the polymer film are employed as described above. Any polymer film made of plastic, that is, a thermoplastic resin can be stretched, but a cyclic olefin-based resin film is preferable because it is easy to control retardation. The cyclic olefin-based resin constituting the cyclic olefin-based resin film refers to a resin composed of, for example, a polymer or copolymer of cyclic olefins such as norbornene or polycyclic norbornene-based monomers (cyclic olefin-based resin), This cyclic olefin resin may contain a partial ring-opened structure. In addition, a cyclic olefin-based resin having a ring-opened structure can also be hydrogenated. Further, the cyclic olefin-based resin may be, for example, a mixture of cyclic olefins and chain olefins or vinylated aromatic compounds (styrene, etc.) based on the point of not significantly impairing transparency, or the point of not significantly increasing hygroscopicity. copolymer. In addition, a polar group may be introduced into the molecule of the cyclic olefin-based resin.

When the cyclic olefin resin is a copolymer of a cyclic olefin and a chain olefin or an aromatic compound having a vinyl group, the chain olefin is ethylene or propylene, and the vinyl aromatic compound is styrene, α- Methyl styrene and alkyl substituted styrene, etc. In such a copolymer, the content ratio of the structural unit derived from a cyclic olefin is 50 mol% or less, for example, about 15 to 50 mol% based on the total structural units of the cyclic olefin resin. When the cyclic olefin-based resin is a terpolymer obtained from a cyclic olefin, a chain olefin, and a vinylated aromatic compound, for example, the content ratio of the structural unit derived from the chain olefin relative to the cyclic olefin-based resin The total structural units are about 5 to 80 mol%, and the content ratio of the structural units derived from vinylated aromatic compounds is about 5 to 80 mol%. The cyclic olefin-based resin of such a terpolymer has an advantage that the amount of high-valent cyclic olefin used can be relatively reduced when producing the cyclic olefin-based resin.

Cyclic olefin-based resins capable of producing a cyclic olefin-based resin film are readily available on the market. Commercially available cyclic olefin-based resins include "Topas" [Ticona Corporation (Germany)]; "Aiton" [JSR (Co., Ltd.)]; (strain)]; "APEL" [manufactured by Mitsui Chemicals (Co., Ltd.)], etc. Such a cyclic olefin-based resin can be formed into a film (cyclic olefin-based resin film) by a known film-forming method such as a solvent casting method or a melt extrusion method. In addition, a cyclic olefin-based resin film already sold in the form of a film can also be used. Such commercially available cyclic olefin-based resin films include, for example, "Escina" and "SCA40" [Sekisui Chemical Industry Co., Ltd.]; "Zenoa Film" [Optes Co., Ltd.]; [JSR (strain)] and so on.

Next, a method for imparting retardation to a polymer film will be briefly described. A polymer film can be provided with phase difference by a known stretching method. For example, a roll (roll body) in which a polymer film is wound up into a roll is prepared, the film is continuously unwound from the roll body, and the unwound output film is conveyed to a heating furnace. The set temperature of the heating furnace is in the range of near the glass transition temperature of the polymer film (°C) to [glass transition temperature + 100] (°C), preferably near the glass transition temperature (°C) to [glass transition temperature +50] (°C) range. In this heating furnace, when the film is stretched in the direction in which the film travels or in a direction perpendicular to the direction of travel, the conveying direction or tension is adjusted to incline at an arbitrary angle, and a uniaxial or biaxial thermal stretching treatment is performed. The stretching ratio is usually in the range of about 1.1 to 6 times, preferably in the range of about 1.1 to 3.5 times. The method of stretching in an oblique direction is not particularly limited as long as the orientation axis can be continuously inclined at a desired angle, and a known stretching method can be used. Such stretching methods include, for example, the methods described in JP-A-50-83482 or JP-A-2-113920.

When used as a transparent substrate, the thickness of the polymer film is preferably thinner in terms of having a weight that can be handled practically and in order to ensure sufficient transparency, but if it is too thin, the strength will decrease and the workability will be poor. trend. Therefore, the appropriate thickness of these films is, for example, approximately 5 to 300 μm, preferably 20 to 200 μm. When this polarizing film is used as a circularly polarizing plate to be described later, it is particularly preferable that the thickness of the film is approximately 20 to 100 μm in view of mobile use of a display device using the circularly polarizing plate.

In addition, when imparting retardation to a film by stretching, the thickness after stretching is determined by the thickness of the film before stretching and the stretching ratio.

<Orientation film>

It is preferable to form an orientation film on the base material used for manufacture of this polarizing film. At this time, the composition for forming a polarizing film is coated on the alignment film. Therefore, it is preferable that the alignment film has solvent resistance to the extent that it does not dissolve through application of the composition for forming a polarizing film or the like. In addition, it is also preferable to have heat resistance in heat treatment for solvent removal or liquid crystal alignment. For the alignment film, an alignment polymer can be used.

The aforementioned oriented polymers include, for example, polyamide or gelatin having an amide bond in the molecule, polyamic acid of polyimide and its hydrolyzate having an imide bond in the molecule, polyvinyl alcohol, alkyl modified Polymers such as polyvinyl alcohol, polyacrylamide, polyoxazole, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid or polyacrylates. Among them, polyvinyl alcohol is preferable. These alignment polymers which form an alignment film can be used individually or in mixture of 2 or more types.

The alignment polymer can be applied on a substrate as an alignment polymer composition (orientation polymer-containing solution) dissolved in a solvent to form an alignment film on the substrate. The solvent used in the alignment polymer composition is not particularly limited, specifically, water; methanol, ethanol, ethylene glycol, isopropanol, propylene glycol, methyl cellosolve, butyl cellosolve, and propylene glycol monomethyl ether Alcohol solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate and ethyl lactate and other ester solvents; acetone, methyl ethyl ketone Ketone solvents such as , cyclopentanone, cyclohexanone, methyl amyl ketone and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; aromatic hydrocarbon solvents such as toluene and xylene; acetonitrile Nitrile solvents such as tetrahydrofuran and dimethoxyethane and other ether solvents; chlorine-substituted hydrocarbon solvents such as chloroform and chlorobenzene, etc. These organic solvents may be used alone or in combination of multiple types.

In addition, the alignment polymer composition used for forming an alignment film can use a commercially available alignment film material as it is. Examples of commercially available alignment film materials include Suneva (registered trademark, manufactured by Nissan Chemical Industry Co., Ltd.), Optima (registered trademark, manufactured by JSR Corporation), and the like.

As a method of forming an alignment film on the above-mentioned base material, for example, on the above-mentioned base material, coat the above-mentioned alignment polymer composition or a commercially available alignment film material, and then perform an annealing treatment to form an alignment film on the above-mentioned base material. . The thickness of the alignment film obtained above is, for example, in the range of 10 nm to 10000 nm, preferably in the range of 10 nm to 1000 nm.

In order to impart an anchoring force to the above-mentioned alignment film, rubbing (rubbing method) is preferably performed as necessary. By imparting an anchoring force, the polymerizable smectic liquid crystal compound can be aligned in a desired direction.

As a method of imparting an anchoring force by a rubbing method, for example, preparing a rotating rubbing roll wrapped with a rubbing cloth, and placing a laminate having a coating film for forming an alignment film on a substrate on a load A method in which the coating film for forming an alignment film is brought into contact with the rotating rubbing roller by conveying it to a rotating rubbing roller on a table.

In addition, a so-called photo-alignment film can also be used. The photo-alignment film may also form a photo-alignment inducing layer, and an anchoring force may be imparted by irradiating polarized light (preferably polarized UV). When forming the photo-alignment-inducing layer, first, a composition containing a polymer or monomer having a photoreactive group and a solvent (hereinafter also referred to as "photo-alignment film-forming composition" as the case may be) is prepared. The photoreactive group means a group that produces liquid crystal alignment ability by irradiating light (photoirradiation). Specifically, it refers to a photoreactive group capable of causing liquid crystal alignment ability, such as induced alignment or isomerization reaction, dimerization reaction, photocrosslinking reaction, or photodecomposition reaction of product molecules by light irradiation. Among the photoreactive groups, groups utilizing dimerization reaction or photocrosslinking reaction are preferable in terms of being excellent in orientation and maintaining the smectic liquid crystal state at the time of forming the polarizing film. As the photoreactive group that can take place above reaction, it is preferred to have an unsaturated bond, especially a group with a double bond, especially preferably a group selected from carbon-carbon double bond (C=C bond), carbon-nitrogen double bond ( C=N bond), nitrogen-nitrogen double bond (N=N bond) and carbon-oxygen double bond (C=O bond) at least one bond group.

The photoreactive group having C═C bond includes, for example, vinyl group, polyalkenyl group, stilbene group, styrylpyridyl group, heterostilbene group, chalcone group, cinnamoyl group and the like. Examples of the photoreactive group having a C=N bond include groups having structures such as aromatic Schiff bases and aromatic hydrazones. The photoreactive group with N=N bond can be enumerated, azophenyl, azonaphthyl, aromatic heterocyclic azo, diazo and formazan, or based on azobenzene group of structures. Examples of photoreactive groups having a C=O bond include benzophenone groups, coumarin groups, anthraquinone groups, and maleimide groups. These groups may have substituents such as alkyl, alkoxy, aryl, allyloxy, cyano, alkoxycarbonyl, hydroxyl, sulfonic acid and haloalkyl.

Among them, photoreactive groups that can undergo photodimerization reactions are preferred, based on the fact that the amount of polarized light irradiation required for photoalignment is relatively small, and it is easy to obtain a photoalignment film with excellent thermal stability or stability over time, preferably cinnamoyl and zirconium. ear keto group. Furthermore, as a polymer having a photoreactive group, it is particularly preferable that the terminal portion of the side chain of the polymer has a cinnamoyl group having a cinnamic acid structure.

A photo-alignment-inducing layer (film) can be formed on a transparent substrate by coating on a transparent substrate as a composition for forming a photo-alignment film in which a polymer or a monomer having a photoreactive group is dissolved in a solvent . The solvent used in this composition is not particularly limited, and the solvent used in the above-mentioned alignment polymer composition can be used according to the solubility of the polymer or monomer having a photoreactive group.

With respect to the photo-alignment film-forming composition, the concentration of the polymer or monomer having a photoreactive group may vary according to the type of polymer or monomer having the photoreactive group or the desired photo-alignment effect. The thickness of the film is appropriately adjusted, but it is preferably at least 0.2% by mass, particularly preferably in the range of 0.3 to 10% by mass, in terms of solid content concentration. In addition, the composition for forming a photo-alignment film may contain a polymer material such as polyvinyl alcohol or polyimide, or a sensitizer within a range that does not significantly impair the properties of the photo-alignment film.

As a method for coating the above-mentioned oriented polymer or polymer or monomer having a photoreactive group on a transparent substrate, spin coating method, extrusion method, gravure coating method, die coating method, rod coating method, etc. can be used. Known methods such as coating methods such as coating methods and coating methods, printing methods such as flexo methods, and the like. In addition, when the production of this polarizing film is carried out by the continuous production method of the roll-to-roll type (Roll to Roll type) described later, the coating method is usually a printing method such as a gravure coating method, a die coating method, or a flexo method. .

In addition, when rubbing or polarized light irradiation is performed, if masking (masking) is performed, a plurality of regions (patterns) having different orientation directions can be formed.

<Manufacturing method of this polarizing film>

On the alignment film formed on the above (transparent) substrate, the composition for forming a polarizing film of the present invention is coated to obtain a coating film. The method (coating method) for coating the composition for forming a polarizing film on the alignment film can be enumerated, for example, the same as coating an alignment polymer or a polymer having a photoreactive group (monomer) on a transparent substrate. ) in the same way as the instantiated method.

Next, the solvent is removed by drying under the condition that the above-mentioned polymerizable smectic liquid crystal compound contained in the coating film does not polymerize, thereby forming a dry coating film. Examples of drying methods include natural drying, air drying, heat drying, and reduced pressure drying. In this case, it is preferable to convert the nematic phase into the smectic phase after the liquid crystal state of the polymerizable smectic liquid crystal composition contained in the dry film is changed to the nematic phase (nematic liquid crystal state). When forming the smectic phase through the nematic phase as described above, for example, the following method can be adopted: heating to a temperature above the temperature at which the polymerizable smectic liquid crystal compound contained in the dry film changes into a nematic liquid crystal state, and then cooling to a temperature at which the polymerizable smectic liquid crystal compound exhibits a smectic liquid crystal state.

When the polymerizable smectic liquid crystal compound in the above-mentioned dry film is made to be in a smectic liquid crystal state, or when the polymerizable smectic liquid crystal compound is made to be in a smectic liquid crystal state via a nematic liquid crystal state, by measuring The conditions (heating conditions) for controlling the liquid crystal state can be easily obtained by determining the phase transition temperature of the smectic liquid crystal compound. The measurement conditions for measuring the phase transition temperature will be described in the examples of the present application.

When polymerizing the above-mentioned polymerizable smectic liquid crystal compound, in order to maintain a good smectic liquid crystal state, as the polymerizable smectic liquid crystal compound, it is preferable to use one containing two or more polymerizable liquid crystal smectic compounds. A composition for forming a polarizing film. Using a composition for forming a polarizing film in which the content ratio of the two or more polymerizable smectic liquid crystal compounds is adjusted, the supercooled state can be temporarily formed after the smectic liquid crystal state is formed via the nematic phase , has the advantage of being easy to maintain the liquid crystal state of the advanced smectic phase.

Next, the polymerization process of the polymerizable smectic liquid crystal compound will be described. Here, after making the above-mentioned composition for forming a polarizing film contain a photopolymerization initiator to make the liquid crystal state of the polymerizable smectic liquid crystal compound in the dried film into a smectic phase, the smectic liquid crystal state is maintained, and the The photopolymerization method of the polymerizable smectic liquid crystal compound is described in detail. In the photopolymerization, as the light irradiating the dry film, the type of the photopolymerization initiator contained in the dry film, or the kind of the polymerizable smectic liquid crystal compound (in particular, the type of the polymerizable smectic liquid crystal compound) can be selected. The type of photopolymerizable group) and the amount thereof are appropriately selected from the group consisting of visible light, ultraviolet light, and laser light or by active electron beams. Among them, ultraviolet light is preferable based on the point that it is easy to control the progress of the polymerization reaction, or that a device widely used in this field can be used as a device involved in photopolymerization. Therefore, it is preferable to select the kind of the polymerizable smectic liquid crystal compound or the photopolymerization initiator contained in the above-mentioned composition for forming a polarizing film so that it can be photopolymerized by ultraviolet light. In addition, when polymerizing, the film may be cooled and dried by an appropriate cooling method while irradiating ultraviolet light to control the polymerization temperature. If the polymerization of the polymerizable smectic liquid crystal compound can be carried out at a lower temperature by adopting such a cooling method, even if the above-mentioned transparent substrate is used with a relatively low heat resistance, it is possible to properly form polarized light. Advantages of the film. In addition, at the time of photopolymerization, the present polarizing film in which a pattern is formed can also be obtained by performing masking, development, or the like.

By carrying out photopolymerization as described above, the above-mentioned polymerizable smectic liquid crystal compound is polymerized while maintaining a smectic phase, preferably a high-order smectic liquid crystal state mentioned above, to form the present polarizing film. The present polarizing film obtained by polymerizing the polymerizable smectic liquid crystal compound in the liquid crystal state maintaining the smectic phase, accompanied by the effect of the above-mentioned azo pigment (1), compared with the existing host-guest type polarizing film, that is, The polarizing film obtained by polymerizing a polymerizable nematic liquid crystal compound while maintaining a nematic liquid crystal state has the advantage that the polarizing performance is much higher than that of the existing polarizing film. Furthermore, it has the advantage of being superior in strength compared to a polarizing film coated only with a dichroic dye or a lyotropic liquid crystal.

The thickness of the polarizing film formed as above is preferably in the range of 0.5 μm to 5 μm, more preferably 1 μm to 5 μm. Therefore, the thickness of the coating film for forming this polarizing film can be determined in consideration of the thickness of the polarizing film to be obtained. In addition, the thickness of the polarizing film can be obtained by measuring with an interference film thickness meter, a laser microscope or a stylus film thickness meter.

In addition, the present polarizing film formed in this way is particularly preferably a polarizing film that obtains a Bragg peak in X-ray diffraction measurement as described above. As a polarizing film which acquires such a Bragg peak, for example, this polarizing film which shows the diffraction peak derived from a hexagonal phase or a crystal phase is mentioned.

In the production of the present polarizing film described above, a member provided with the present polarizing film/(photo) alignment film/transparent base material in this order is produced. This member can be directly used as a polarizer used in a liquid crystal display device. If the manufacturing method of the said polarizer is briefly demonstrated, the manufacturing method will contain the following process of (1)-(5).

(1) A step of preparing a laminate having the above-mentioned alignment film on a transparent substrate;

(2) A step of forming a film composed of the above polarizing film-forming composition on the above-mentioned alignment film of the above-mentioned laminate;

(3) A step of removing the solvent from the film;

(4) a step of making the above-mentioned polymerizable smectic liquid crystal compound contained in the film from which the above-mentioned solvent has been removed into a smectic liquid crystal state;

(5) A step of forming a polarizing film on the alignment film by polymerizing the polymerizable smectic liquid crystal compound with the polymerizable smectic liquid crystal compound maintaining the smectic liquid crystal state.

<Continuous production method of this polarizing film>

As mentioned above, the manufacturing method of this polarizing film was roughly demonstrated, but when this polarizing film is manufactured commercially, the method which can manufacture this polarizing film continuously is required. Such a continuous manufacturing method is a roll-to-roll method, which is sometimes referred to as "this manufacturing method". In addition, in this manufacturing method, the case where a base material is a transparent base material is demonstrated centering.

This manufacturing method has the following steps, for example:

The process of preparing the first roll obtained by winding the transparent base material on the first core;

a step of continuously sending out the transparent substrate from the first roller;

A process of coating a composition containing a polymer having the above-mentioned photoreactive group and a solvent, and continuously forming a first coating film on the transparent substrate;

A step of continuously obtaining a first laminate by drying and removing the solvent from the first coating film to form a first dry film on the transparent substrate;

A process of continuously obtaining a second laminate by forming a photo-alignment film by irradiating the first dry film with polarized light UV;

On the photo-alignment film, coating a composition containing a polymerizable smectic liquid crystal compound, a dichroic pigment and a solvent, and continuously forming a second coating film on the photo-alignment film;

By drying the second coating film under the condition that the polymerizable smectic liquid crystal compound contained in the second coating film does not polymerize, a second dry coating film is formed on the photo-alignment film to continuously obtain The process of the third layered body;

After the polymerizable smectic liquid crystal compound contained in the second dry film is brought into a smectic liquid crystal state, the polymerizable smectic liquid crystal compound is polymerized by maintaining the smectic liquid crystal state to continuously obtain a polarizing film process;

The process of winding up the polarizing film obtained continuously on a 2nd winding core, and obtaining a 2nd roll. Here, referring to FIG. 1, the main part of this manufacturing method is demonstrated.

The first roll 210 in which the transparent substrate is wound around the first core 210A can be easily obtained from the market, for example. As such a transparent substrate that can be purchased from the market in the form of a roll, among the transparent substrates already listed, cellulose ester, cyclic olefin resin, polyethylene terephthalate, or polymethyl ether can be cited. Films made of acrylate, etc. In addition, when this polarizing film is used as a circularly polarizing plate, a transparent substrate to which a phase difference has been given in advance can be easily obtained from the market, for example, a phase plate composed of a cellulose ester or a cyclic olefin resin. Poor film, etc.

Next, the transparent substrate is unwound from the above-mentioned first drum 210 and outputted. The method of unwinding and outputting the transparent substrate can be carried out as follows: a suitable rotating device is installed on the winding core 210A of the first roller 210, and the first roller 210 is rotated by the rotating device. In addition, the following form may also be adopted: in the direction of conveying the transparent substrate from the first roller 210, an appropriate auxiliary roller 300 is provided, and the transparent substrate is unwound and output by the rotation device of the auxiliary roller 300. Furthermore, a form may be adopted in which a rotating device is provided to the first winding core 210A and the auxiliary roller 300 at the same time to unwind and output the transparent substrate while applying an appropriate tension to the transparent substrate.

When the transparent substrate unwound from the first drum 210 passes through the coating device 211A, the above-mentioned composition for forming a photo-alignment film is applied to the surface by the coating device 211A. In order to continuously coat the composition for forming a photo-alignment film as described above, this coating apparatus 211A employs a printing method such as a gravure coating method, a die coating method, or a flexo method.

The film after passing through the coating device 211A corresponds to a laminate of the above-mentioned transparent substrate and the first coating film. The transparent substrate on which the first coating film is formed (laminated) in this way is conveyed to the drying furnace 212A and heated by the drying furnace 212A to be converted into a first laminate composed of the transparent substrate and the first dry film. As the drying furnace 212A, for example, a hot-air drying furnace or the like can be used. The set temperature of the drying furnace 212A is set according to the type of solvent contained in the composition for forming a photo-alignment film coated by the coating device 211A, and the like. In addition, the drying furnace 212A can be divided into appropriate sections, and the set temperatures of the divided sections can be different, or a plurality of drying furnaces can be arranged in series, and the drying furnaces can be set to be different from each other. The temperature is operated at a certain temperature, and at the same time, the film is sequentially transported to the plurality of drying ovens.

Next, the first layered body continuously formed by the heating furnace 212A is subjected to polarized UV irradiation on the surface of the layered body on the first dry film side or the surface on the transparent substrate side through the polarized light UV irradiation device 213A. , thereby converting the first dry film into a light polarizing film. At this time, the film conveyance direction D1 and the orientation direction D2 of the formed photo-alignment film were made to form an angle of approximately 45°. Fig. 5 is a schematic view showing the relationship between the orientation direction D2 of the photo-alignment film formed after irradiating polarized light UV and the conveyance direction D1 of the film. That is, what Fig. 1 shows is that for the surface of the first laminated body after passing through the polarized light UV irradiation device 213A, when observing the transport direction D1 of the film and the orientation direction D2 of the photo-alignment film, the angle formed between them is approximately 45°. °.

The first laminate formed continuously as above is then passed through the coating device 211B, whereby the composition for forming a polarizing film is coated on the photo-alignment film of the first laminate, and then passed through the drying oven 212B to become The polymerizable smectic liquid crystal compound contained in the second laminate or the second dried film of the second laminate forms a laminate in a smectic liquid crystal state. The drying furnace 212B not only has the function of drying and removing the solvent from the composition for forming a polarizing film coated on the photo-alignment film, but also has the function of imparting heat energy to the second dry film so that the above-mentioned second dry film The contained polymerizable smectic liquid crystal compound becomes a smectic liquid crystal state. In addition, as described above, in order to make the polymerizable smectic liquid crystal compound into a smectic liquid crystal state, the polymerizable smectic liquid crystal compound is temporarily made into a nematic liquid crystal state. The body is subjected to multi-stage heat treatment under different heating conditions. Therefore, the drying furnace 212B is preferably constituted by a plurality of sections with different set temperatures set to each other as described for the dry furnace 212A, or a plurality of drying furnaces with different set temperatures are prepared, and the multiple sets are arranged in series. In the form of a drying oven.

After passing through the drying oven 212B, the solvent contained in the composition for forming a polarizing film is sufficiently removed, and the polymerizable smectic liquid crystal compound in the second dry film is transported while maintaining the smectic liquid crystal state. to the light irradiation device 213B. When light is irradiated by the light irradiation device 213B, the polymerizable smectic liquid crystal compound undergoes photopolymerization while maintaining the above-mentioned liquid crystal state, and finally this polarizing film is continuously formed on the alignment film.

The present polarizing film formed continuously as above is wound up on the second winding core 220A in the form of a laminate including a transparent base material and an alignment film, and the form of the second roll 220 is obtained. When this polarizing film formed by winding is obtained as a 2nd roll, it can also be wound together using an appropriate spacer.

As mentioned above, the transparent substrate passes through the first roller/coating device 211A/drying furnace 212A/polarized light UV irradiation device 213A/coating device 211B/drying furnace 212A/light irradiation device 213A in sequence, A polarizing film is continuously produced on the photo-alignment film.

In addition, in the production method shown in Figure 1, although the method of continuous production from the transparent substrate to the polarizing film is illustrated, it can also be produced as follows: for example, the transparent substrate passes through the first roller in sequence /coating device 211A/drying furnace 212A/polarized light UV irradiation device 213A, the first laminated body formed continuously is wound on a mandrel, the first laminated body in the form of a roll is manufactured, and the first laminated body is unwound from the roll and outputted. For the laminated body, the first laminated body unwound and outputted is sequentially passed through the coating device 211B/drying furnace 212A/light irradiation device 213A to obtain the present polarizing film.

The present polarizing film obtained by this production method has a film shape and a long strip shape. When this polarizing film is used for the liquid crystal display device mentioned later, etc., it can use after cutting into a required size according to the scale etc. of this liquid crystal display device.

Above, the configuration and manufacturing method of the polarizing film have been described centering on the form of the laminate of the transparent substrate/photo-alignment film/the polarizing film, but as described above, the polarizing film can also be obtained from the polarizing film The laminate may be in the form of laminating layers or films other than the transparent substrate/photo-alignment film/the present polarizing film on which the photo-alignment film or the transparent substrate is removed. As these layers and films, as mentioned above, this polarizing film may further include a retardation film, and may further include an antireflection layer or a brightness enhancement film.

In addition, by making the transparent substrate itself a retardation film, a circular polarizing plate or an ellipsoidal polarizing plate in the form of a retardation film/photo-alignment film/this polarizing film can be obtained. For example, when using a 1/4 wavelength plate obtained by uniaxial stretching as a retardation film, by setting the irradiation direction of polarized light UV at approximately 45° with respect to the conveying direction of the transparent substrate, roll-to-roll method to fabricate circularly polarized light plates. The 1/4 wavelength plate used in producing such a circularly polarizing plate preferably has a characteristic that the in-plane retardation value with respect to visible light decreases as the wavelength becomes shorter.

In addition, by using a 1/2 wavelength plate as a retardation film, a linear polarizing plate roller whose slow axis is set to be offset from the absorption axis of the polarizing film is produced, on the side opposite to the surface on which the polarizing film is formed. By further forming a 1/4 wavelength plate, a broadband circularly polarized light plate can be obtained.

<Applications of this polarizing film>

The polarizing film can be used in various display devices. A display device refers to a device having a display element, which includes a light-emitting element or a light-emitting device as a light-emitting source. Display devices include, for example, liquid crystal display devices, organic electroluminescence (EL) display devices, inorganic electroluminescence (EL) display devices, electron emission display devices (such as field emission display devices (FED), surface field emission display devices (SED)), electronic paper (display devices using electronic ink or electrophoretic elements, plasma display devices, projection display devices (such as grid light valve (GLV) display devices, display devices with digital microlens devices (DMD) ) and piezoelectric ceramic displays, etc. Liquid crystal display devices also include any of transmissive liquid crystal display devices, semi-transmissive liquid crystal display devices, reflective liquid crystal display devices, direct-view liquid crystal display devices, and projection type liquid crystal display devices. These display The device may be a display device that displays two-dimensional images, or a stereoscopic display device that displays three-dimensional images.

The present polarizing film can be used particularly effectively for a display device of an organic electroluminescence (EL) display device or an inorganic electroluminescence (EL) display device.

2 and 5 are schematic diagrams showing a cross-sectional configuration of a liquid crystal display device (hereinafter referred to as "the liquid crystal display device" as the case may be) 10 using the polarizing film. The liquid crystal layer 17 is sandwiched between the two substrates 14a and 14b.

8 and 10 are schematic diagrams showing a cross-sectional structure of an EL display device (hereinafter referred to as "this EL display device" as the case may be) using this polarizing film.

FIG. 11 is a schematic diagram showing the configuration of a projection-type liquid crystal display device using the present polarizing film.

First, the present liquid crystal display device 10 shown in FIG. 2 will be described.

The color filter 15 is arranged on the liquid crystal layer 17 side of the substrate 14a. The color filter 15 is disposed at a position facing the pixel electrodes 22 sandwiching the liquid crystal layer 17 , and the black matrix 20 is disposed at a position facing a region between the pixel electrodes. The transparent electrode 16 is disposed on the side of the liquid crystal layer 17 and covers the color filter 15 and the black matrix 20 .

In addition, there may be a protective film layer (not shown) between the color filter 15 and the transparent electrode 16 .

On the side of the liquid crystal layer 17 of the substrate 14b, thin film transistors 21 and pixel electrodes 22 are regularly arranged. The pixel electrode 22 is disposed at a position facing the color filter 15 sandwiching the liquid crystal layer 17 . Between the thin film transistor 21 and the pixel electrode 22, an interlayer insulating film 18 having a connection hole (not shown) is disposed.

As the substrate 14a and the substrate 14b, a glass substrate and a plastic substrate are used.

The glass substrate and the plastic substrate involved can be the same substrate as the transparent base materials listed in the manufacture of this polarizing film. In addition, the transparent substrate 1 of the present polarizing film can also serve as the substrate 14a and the substrate 14b. When a high-temperature heating process is required to manufacture the color filter 15 or the thin film transistor 21 formed on the substrate, a glass substrate or a quartz substrate is preferable.

The thin film transistor can adopt an optimal form according to the material of the substrate 14b. The thin film transistor 21 may be a high temperature polysilicon transistor formed on a quartz substrate, a low temperature polysilicon transistor formed on a glass substrate, or an amorphous silicon transistor formed on a glass substrate or a plastic substrate. In order to further reduce the size of the present liquid crystal display device, a driver IC may be formed on the substrate 14b.

A liquid crystal layer 17 is arranged between the transparent electrode 16 and the pixel electrode 22 . In the liquid crystal layer 17 , spacers 23 are arranged to keep the distance between the substrate 14 a and the substrate 14 b constant. 2 shows a columnar spacer, but this does not mean that the spacer is limited to a columnar shape, as long as the distance between the substrate 14a and the substrate 14b can be kept constant, the shape can be arbitrary.

Of the layers formed on the substrate 14a and the substrate 14b, an alignment film for aligning liquid crystals in a desired direction may be disposed on the surface in contact with the liquid crystal layer 17, respectively. In addition, this polarizing film can be arranged inside the liquid crystal cell, that is, this polarizing film can be arranged on the side of the surface in contact with the liquid crystal layer 17 . Such a form is hereinafter referred to as "inline". The embedded type will be described later in detail.

Each member is sequentially laminated in the order of substrate 14a, color filter 15, black matrix 20, transparent electrode 16, liquid crystal layer 17, pixel electrode 22, interlayer insulating film 18, thin film transistor 21, and substrate 14b.

Among the substrates 14a and 14b sandwiching the liquid crystal layer 17, polarizers 12a and 12b are provided outside the substrate 14b, and at least one of the polarizers includes this polarizing film.

Furthermore, it is preferable to laminate retardation layers (for example, 1/4 wavelength plate or optical compensation film) 13a and 13b. Among the polarizers 12a and 12b, by arranging this polarizing film on the polarizer 12b, the function of converting incident light into linearly polarized light can be provided to the liquid crystal display device 10 . In addition, according to the structure of the liquid crystal display device, or the type of the liquid crystal compound contained in the liquid crystal layer 17, the retardation films 13a and 13b may not be configured. In this case, since the retardation film can be used as a retardation layer, the retardation layer 13a and/or 13b in FIG. 2 can also be omitted. A polarizing film may be further provided on the light emitting side (outer side) of the polarizer including this polarizing film.

In addition, an antireflection film for preventing reflection of external light may be arranged on the outside of the polarizer including the polarizing film (when the polarizing film is further arranged on the polarizing film, on the outside).

As described above, this polarizing film can be used in the polarizer 12a or 12b of the liquid crystal display device 10 of FIG. 2 . By disposing the polarizing film on the polarizers 12a and/or 12b, there is an effect that the thickness reduction of the liquid crystal display device 10 can be achieved.

When this polarizing film is used for the polarizer 12a or 12b, the order of lamination is not specifically limited. This will be described with reference to enlarged views of parts A and B encircled by dotted lines in FIG. 2 .

FIG. 3 is an enlarged schematic cross-sectional view of part A in FIG. 2 . (A1) of FIG. 3 shows that when the polarizer 100 is used as the polarizer 12a, from the retardation layer 13a side, the polarizing film 3, the photo-alignment film 2 and the transparent substrate 1 are arranged in this order. . In addition, (A2) of FIG. 3 shows the arrangement in which the transparent base material 1, the photo-alignment film 2, and the present polarizing film 3 are sequentially arranged from the retardation layer 13a side.

FIG. 4 is an enlarged schematic view of part B of FIG. 2 . (B1) of FIG. 4 shows that when the polarizer 100 is used as the polarizer 12b, the transparent substrate 1, the photo-alignment film 2, and the polarizing film 3 are arranged in this order from the retardation film 13b side. What (B2) of Fig. 4 shows is that when using the polarizer 100 as the polarizer 12b, from the phase difference film 13b side, the setting of disposing the polarizing film 3, the photo-alignment film 2 and the transparent substrate 1 in sequence .

Outside the polarizer 12b, a backlight module 19 as a light source is arranged.

The backlight module 19 includes a light source, a light guide, a reflector, a diffusion sheet, and a viewing angle adjustment sheet. Examples of light sources include electroluminescence, cold cathode tubes, hot cathode tubes, light emitting diodes (LEDs), laser light sources, and mercury lamps. In addition, the type of this polarizing film can be selected according to the characteristics of these light sources.

When the liquid crystal display device 10 is a transmissive liquid crystal display device, the white light emitted from the light source in the backlight module 19 enters the light guide body, changes the optical path through the reflector, and is diffused by the diffusion sheet. After the diffused light is adjusted to have desired directivity by the viewing angle adjustment sheet, it enters the polarizer 12 b from the backlight module 19 .

Of the unpolarized incident light, only a certain linearly polarized light passes through the polarizer 12b of the liquid crystal panel. The linearly polarized light passes through the phase difference layer 13b, is converted into circularly polarized light or elliptical polarized light, and then passes through the substrate 14b, the pixel electrode 22, etc. in turn, and reaches the liquid crystal layer 17.

Here, according to whether there is a potential difference between the pixel electrode 22 and the opposite transparent electrode 16 , the alignment state of the liquid crystal molecules contained in the liquid crystal layer 17 is changed, thereby controlling the brightness of light emitted from the liquid crystal display device 10 . When the liquid crystal layer 17 is in an alignment state that directly transmits polarized light, the polarized light passes through the liquid crystal layer 17 and the transparent electrode 16, and light in a certain wavelength range passes through the color filter 15 to reach the polarizer 12a, and the liquid crystal display device displays is the brightest color determined by the filter.

On the contrary, when the liquid crystal layer 17 is in the alignment state of converting polarized light to transmit it, the light transmitted through the liquid crystal layer 17, the transparent electrode 16 and the color filter 15 is absorbed by the polarizer 12a. Thus, the pixel appears black. In the intermediate alignment state of these two states, the brightness of the light emitted from the liquid crystal display device 10 is also intermediate between the above-mentioned two states, so that the pixel displays an intermediate color.

When the present liquid crystal display device 10 is a transflective liquid crystal display device, it is preferable to use a polarizing film further laminated with a 1/4 wavelength plate (circular polarizing plate). In this case, the pixel electrode 22 has a transmissive portion made of a transparent material and a reflective portion formed of a light-reflecting material, and the transmissive portion displays an image similarly to the above-mentioned transmissive liquid crystal display device. On the other hand, in the reflective part, external light enters the liquid crystal display device, and the circularly polarized light transmitted through the polarizing film passes through the liquid crystal layer 17 through the function of the 1/4 wavelength plate further provided by the polarizing film, and passes through the pixel electrode. 22 reflections, thus used for display.

Next, a suitable in-cell liquid crystal display device (this liquid crystal display device 24 ) using this polarizing film will be described with reference to FIG. 5 .

This liquid crystal display device 24, by substrate 14a, polarizer 12a, retardation film 13a, color filter 15 and black matrix 20, transparent electrode 16, liquid crystal layer 17, pixel electrode 22, interlayer insulating film 18 and thin film transistor 21 , a retardation film 13b, a polarizer 12b, a substrate 14b, and a backlight module 19 are sequentially laminated. In this configuration, it is preferable to use this polarizing film as the polarizer 12a. In this configuration, the polarizing film can also be arranged in order of the transparent substrate 1, the photo-alignment film 2 and the polarizing film 3, so that the transparent substrate on the polarizer doubles as the substrate 14a. With this configuration, the function of converting incident light into linearly polarized light is provided to the present liquid crystal display device 24 provided with the present polarizing film. Also, as in the present liquid crystal display device 10 , depending on the type of liquid crystal compound contained in the liquid crystal layer 17 , the retardation layers 13 a and 13 b may not be disposed.

Next, the present EL display device 30 using the present polarizing film will be described with reference to FIG. 8 . When using this polarizing film in this EL display device, it is preferable to use this polarizing film as a circularly polarizing plate (hereinafter referred to as "this circularly polarizing plate" depending on the case). This circular polarizing plate has two embodiments. Therefore, before describing the configuration and the like of the EL display device 30, two embodiments of the circularly polarizing plate will be described with reference to FIG. 6 .

(A) of FIG. 6 is a schematic cross-sectional view of the first embodiment of the circularly polarizing plate 110 . This first embodiment is a circularly polarizing plate 110 in which a retardation layer (retardation film) 4 is further provided on a polarizing film 3 in a polarizer 100 . (B) of FIG. 6 is a schematic cross-sectional view of the second embodiment of the circular polarizing plate 110 . This second embodiment is the following circularly polarizing plate 110, which uses the transparent base material 1 (retardation film 4) to which retardation has been given in advance as the transparent base material 1 used when manufacturing the polarizer 100, and the transparent base material 1 itself also functions as the retardation layer 4 .

Here, the manufacturing method of the circularly polarizing plate 110 will be described first. As described in the second embodiment of the circularly polarizing plate 110 above, in the present manufacturing method of the present polarizing film 100, the transparent substrate 1 to which retardation has been provided in advance, that is, the retardation film can be used as the transparent substrate. 1 for manufacturing. In the first embodiment of the circularly polarizing plate 110, the retardation layer 4 may be formed by bonding a retardation film on the present polarizing film 3 produced by this manufacturing method. In addition, according to this manufacturing method, when the polarizing film 100 is manufactured in the form of the second roller 220, the following method can be adopted: the polarizing film 100 is unwound from the second roller 220, cut into a predetermined size, and the phase The difference film is bonded to the cut-off polarizing film 100; but by preparing the third roll on which the retardation film is wound on the core, the circular polarizing plate 110 which is shaped like a film and is elongated can be continuously manufactured. .

A method of continuously manufacturing the circular polarizing plate 110 according to the first embodiment will be described with reference to FIG. 7 . The manufacturing method involved consists of the following steps:

While continuously unwinding and outputting the polarizing film 100 from the above-mentioned second drum 220, the process of continuously unwinding and outputting the above-mentioned retardation film from the third drum 230 formed by winding the retardation film;

The polarizing film provided on the polarizing film 100 that is unwound from the second drum 220 is continuously attached to the retardation film that is unwound from the third drum to form the polarizing plate 110;

The process of winding the formed circularly polarizing plate 110 on the fourth winding core 240A to obtain the fourth roll 240 .

Preferred embodiments of this circularly polarizing plate include, for example, the following <X1>, <X2>, and the like.

<X1> This circular polarizing plate which has this polarizing film and a λ/4 layer and satisfies the following requirements (A1) and (A2)

(A1) The angle formed by the absorption axis of the polarizing film and the slow axis of the above-mentioned λ/4 layer is approximately 45°;

(A2) The front retardation value of the above-mentioned λ/4 layer measured under light having a wavelength of 550 nm is within the range of 100 to 150 nm

<X2> A circular polarizing plate that has this polarizing film, a λ/2 layer, and a λ/4 layer in this order, and satisfies all of the following requirements (B1) to (B4)

(B1) The angle formed by the absorption axis of the above-mentioned polarizing film and the slow axis of the above-mentioned λ/2 layer is approximately 15°;

(B2) The angle formed by the slow axis of the above-mentioned λ/2 layer and the slow axis of the above-mentioned λ/4 layer is approximately 60°;

(B3) The front retardation value of the above-mentioned λ/2 layer measured under light with a wavelength of 550 nm is in the range of 200 to 300 nm;

(B4) The front retardation value of the above-mentioned λ/4 layer measured under light with a wavelength of 550 nm is in the range of 100 to 150 nm.

Although the manufacturing method of the first embodiment of the circularly polarizing plate 110 has been described above, when bonding the polarizing film 3 and the retardation film in the polarizer 100, an appropriate adhesive can also be used. The adhesive layer formed of this adhesive bonded the polarizing film 3 and the retardation film together.

Next, the present EL display device including the present circularly polarizing plate 110 will be described with reference to FIG. 8 .

This EL display device 30 is manufactured by laminating an organic functional layer 36 as a light-emitting source and a cathode electrode 37 on a substrate 33 on which a pixel electrode 35 is formed. A circular polarizing plate 31 is disposed on the side opposite to the sandwich substrate 33 and the organic functional layer 36 , and this circular polarizing plate 110 is used as the relevant circular polarizing plate 31 . By applying a positive voltage to the pixel electrode 35 , applying 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 starts to emit light. The organic functional layer 36 as a light emitting source is composed of an electron transport layer, a light emitting layer, a hole transport layer, and the like. The light emitted from the organic functional layer 36 passes through the pixel electrode 35 , the interlayer insulating film 34 , the substrate 33 , and the circular polarizing plate 31 (this circular polarizing plate 110 ). Although an organic EL display device having an organic functional layer 36 has been described, it is also applicable to an inorganic EL display device having an inorganic functional layer.

When manufacturing the present EL display device 30 , first, a thin film transistor 40 of a desired shape is formed on a substrate 33 . Next, an interlayer insulating film 34 is formed, and then a pixel electrode 35 is formed by sputtering to form a pattern. After that, the organic functional layer 36 is laminated.

Next, the circular polarizing plate 31 (this circular polarizing plate 110 ) is provided on the surface of the substrate 33 opposite to the surface on which the thin film transistor 40 is provided.

When the circular polarizing plate 110 is used as the circular polarizing plate 31 , the lamination sequence thereof will be described with reference to the enlarged view of the portion C surrounded by a dotted line in FIG. 8 . When the circularly polarizing plate 110 is used as the circularly polarizing plate 31 , the retardation layer 4 on the circularly polarizing plate 110 is arranged on the substrate 33 side. (C1) of FIG. 9 is an enlarged view of the first embodiment of the circularly polarizing plate 110 used as the circularly polarizing plate 31, and (C2) of FIG. 9 is the circularly polarizing plate of the second embodiment of the present circularly polarizing plate 110. 31 Magnified view used.

Next, members other than the polarizing film 31 (circularly polarizing plate 110 ) of the EL display device 30 will be briefly described.

Examples of the substrate 33 include a sapphire glass substrate, a quartz glass substrate, a soda glass substrate, and a ceramic substrate such as alumina; a metal substrate such as copper; and a plastic substrate.

Although not shown, a thermally conductive film may be formed on the substrate 33 . Examples of the thermally conductive film include diamond thin films (DLC, etc.). When the pixel electrode 35 is reflective, light is emitted from the direction opposite to the substrate 33 . Therefore, not only transparent materials but also non-transparent materials such as stainless steel can be used. The substrate may be in the form of a single one, or a form in which a plurality of substrates are bonded together with an adhesive to form a laminated substrate. In addition, these substrates are not limited to plate shapes, and may be films.

As the thin film transistor 40, for example, a polysilicon transistor or the like may be used. The thin film transistor 40 is provided at the end of the pixel electrode 35 and has a size of approximately 10 to 30 μm. In addition, the size of the pixel electrode 35 is approximately 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 the function of being electrically connected to the pixel electrode 35 to suppress the resistance value at a low value. Generally, the wiring electrode is made of Al, Al and a transition metal (but not including Ti), Ti or titanium nitride. Any one or two or more of (TiN).

An interlayer insulating film 34 is provided between the thin film transistor 40 and the pixel electrode 35 . The interlayer insulating film 34 may be formed by sputtering or vacuum deposition of inorganic materials such as silicon oxide such as SiO ₂ or silicon nitride, or may be made of SOG (spin on glass; spin-on-glass method). ), any insulating material such as a silicon oxide layer, photoresist, coating film of resin-based materials such as polyimide and acrylic resin, etc.

On the interlayer insulating film 34, ribs 41 are formed. The ribs 41 are disposed on edge portions of the pixel electrodes 35 (between adjacent pixels). The material of the ribs 41 includes acrylic resin, polyimide resin, and the like. The thickness of the ribs 41 is preferably not less than 1.0 μm and not more than 3.5 μm, more preferably not less than 1.5 μm and not more than 2.5 μm.

Next, an EL element composed of a pixel electrode 35 as a transparent electrode, an organic functional layer 36 as a light-emitting source, and a cathode electrode 37 will be described. The organic functional layer 36 has at least one hole transport layer and one light-emitting layer each, for example, an electron injection and transport layer, a light-emitting layer, a hole transport layer, and a hole injection layer in this order.

The pixel electrode 35 includes, for example, ITO (tin-doped indium oxide), IZO (zinc-doped indium oxide), IGZO, ZnO, SnO ₂ , and In ₂ O ₃ , and is particularly preferably ITO or IZO. The thickness of the pixel electrode 35 may be at least a predetermined thickness enough to allow sufficient hole injection, and is preferably about 10 to 500 nm.

The pixel electrode 35 can be formed by vapor deposition (preferably sputtering method). The sputtering gas is not particularly limited, and an inert gas such as Ar, He, Ne, Kr, and Xe, or a mixed gas thereof may be used.

As the constituent material of the cathode electrode 37, metal elements such as K, Li, Na, Mg, La, Ce, Ca, Sr, Ba, Al, Ag, In, Sn, Zn, and Zr can be used, but in consideration of improving the electrode For operational stability, it is preferable to use a two-component or three-component alloy body selected from the exemplified metal elements. The alloy body is preferably, for example, Ag·Mg (Ag: 1-20 at%), Al·Li (Li: 0.3-14 at%), In·Mg (Mg: 50-80 at%) and Al·Ca (Ca: 5-20 at% )Wait.

The cathode electrode 37 can be formed by vapor deposition, sputtering, or the like. The thickness of the cathode electrode 37 is preferably 0.1 nm or more, preferably 1 to 500 nm or more.

The hole injection layer has the function of facilitating hole injection from the pixel electrode 35 , and the hole transport layer has the function of transporting holes and blocking electrons, and is also called a charge injection layer and a charge transport layer.

The thickness of the light-emitting layer, the total thickness of the hole injection layer and the hole transport layer, and the thickness of the electron injection and transport layer are not particularly limited, and vary depending on the formation method, but are preferably about 5 to 100 nm in thickness. Various organic compounds can be used in the hole injection layer or the hole transport layer. When forming the hole injecting and transporting layer, the light emitting layer, and the electron injecting and transporting layer, a vacuum vapor deposition method can be used because a homogeneous thin film can be formed.

As the organic functional layer 36 of the light-emitting source, it is possible to use a material that emits light from a singlet exciton (fluorescence), a material that emits light from a triplet exciton (phosphorescence), or a material that emits light from a singlet exciton (phosphorescence). Fluorescent) materials and materials using materials derived from triplet exciton emission (phosphorescence), materials made of organic materials, materials containing materials made of organic materials and materials made of inorganic materials, high molecular materials, low molecular materials , Materials containing high-molecular materials and low-molecular materials, etc. However, it is not limited thereto, and the organic functional layer 36 using various materials known as EL elements can be applied to the EL display device 30 .

A desiccant 38 is arranged between the cathode electrode 37 and the space of the package cover 39 . This is because the organic functional layer 36 is not resistant to moisture. Moisture is absorbed by the desiccant 38 to prevent deterioration of the organic functional layer 36 .

FIG. 10 is a schematic diagram showing a cross-sectional configuration of another embodiment of the EL display device 30 . This EL display device 30 has a packaging structure using a thin film packaging film 41, and can also obtain emitted light from the opposite surface of the array substrate.

As the thin film encapsulation film 41 , a DLC film obtained by vapor-depositing DLC (diamond-like carbon) on an electrolytic capacitor film is preferably used. The DLC film has a characteristic of very poor moisture permeability, and its moisture-proof performance is high. Alternatively, a DLC film or the like may be directly vapor-deposited on the surface of the cathode electrode 37 to form it. Alternatively, multiple layers of resin thin films and metal thin films may be laminated to form the thin film encapsulation film 41 .

As mentioned above, the novel polarizing film (this polarizing film) which concerns on this invention, and the novel display device (this liquid crystal display device and this EL display device) provided with this polarizing film are provided.

Finally, a projection type liquid crystal display device using this polarizing film will be described.

FIG. 11 is a schematic diagram of a projection-type liquid crystal display device using the present polarizing film.

This polarizing film is used as the polarizer 142 and/or the polarizer 143 of this projection type liquid crystal display device.

A beam of light emitted from a light source (for example, a high-pressure mercury lamp) 111 as a light source first passes through the first lens array 112, the second lens array 113, the polarization conversion element 114, and the compound lens 115, thereby converting the reflected beam cross-section Uniform brightness and polarized light.

Specifically, the beam of light emitted from the light source 111 is divided into a plurality of tiny beams of light through the first lens array 112 formed in a matrix by microlenses 112 a. The second lens array 113 and compound lens 115 are arranged so that the divided beams of light can respectively irradiate the entirety of the three liquid crystal panels 140R, 140G, and 140B as illumination objects, thereby reducing the surface energy of the incident side of each liquid crystal panel. A uniform illuminance is obtained as a whole.

The polarization conversion element 114 is composed of a polarization beam splitting array, and is arranged between the second lens array 113 and the composite lens 115 . In this way, random polarized light in the light source can be converted into polarized light with a specific polarization direction in advance, which has the effect of reducing light loss in the incident-side polarizer described later and improving screen brightness.

As described above, the light whose brightness has been uniformed and polarized passes through the reflector 122 and passes through the dichroic mirrors 121, 123, and 132 for separating the three primary colors of RGB in sequence, and is separated into a red channel, a green channel, and a blue channel. , respectively incident on the liquid crystal panels 140R, 140G, and 140B.

In the liquid crystal panels 140R, 140G, and 140B, the polarizer 142 is arranged on the incident side, and the polarizer 143 is arranged on the outgoing side. This polarizing film can be used for the polarizer 142 and the polarizer 143 .

The polarizer 142 and the polarizer 143 arranged in each RGB optical path are arranged so that their respective absorption axes are perpendicular 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 of each pixel controlled according to an image signal into a light quantity.

The present polarizing film 100 can be usefully used as a polarizing film excellent in durability in each of the optical paths of the blue channel, the green channel, and the red channel by selecting the type of dichroic dye suitable for the corresponding channel.

According to the image data of the liquid crystal panels 140R, 140G, and 140B, the incident light is transmitted with different transmittances for each pixel, and the resulting optical image is synthesized by the cross dichroic prism 150 , enlarged and projected onto the projection lens 170 through the projection lens 170 . on screen 180.

Examples of electronic paper include devices that display molecules such as optical anisotropy and dye molecular orientation; devices that display particles such as electrophoresis, particle movement, crystal grain rotation (particle backing), and phase change; Devices that display by moving one end; devices that display by molecular color/phase change; devices that display by molecular light absorption; devices that display by combining electrons and holes to generate self-luminescence, etc. More specifically, microcapsule type electrophoresis, horizontal movement type electrophoresis, vertical movement type electrophoresis, spherical torsion sphere type, magnetic torsion sphere type, cylindrical torsion sphere type, charged carbon powder, electronic powder fluid, magnetophoresis type, magnetothermal Inductive, electrowetting, light scattering (transparency/turbidity change), cholesteric liquid crystal/photoconductive layer, cholesteric liquid crystal, bistable nematic liquid crystal, ferroelectric liquid crystal, dichroic dye liquid crystal dispersion type, Movable film, color change by leuco dye, photochromic, electrochromic, electrodeposition, flexible organic EL, etc. Electronic paper can be applied not only for personal use of text or images, but also for advertising display (signage) and the like. According to the polarizing film, the thickness of electronic paper can be reduced.

As a three-dimensional display device, a method in which different retardation films are alternately arranged such as a micro polarizing film (μPol) formula has been proposed (Japanese Patent Application Laid-Open No. 2002-185983), but the optical film of the present invention is used as a polarizing film. In this case, since a pattern can be easily formed by printing, inkjet, photolithography, etc., the manufacturing process of the display device can be shortened, and a phase difference film is not required.

Example

The present invention will be described in further detail below through examples. Unless otherwise specified, "%" and "part" in an example are mass % and a mass part.

In this example, the following polymerizable smectic liquid crystal compounds were used.

Compound (2-6) (compound represented by the following formula (2-6))

Compound (2-6) was synthesized by the method described in Lub et al. Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996).

[Measurement of Phase Transition Temperature]

The phase transition temperature of the compound (2-6) was confirmed by obtaining the phase transition temperature of the film composed of the compound (2-6). Its operation is as follows.

On the glass substrate on which the alignment film was formed, a film composed of the compound (2-6) was formed, and while heating, the structure was observed by using a polarizing microscope (BX-51, manufactured by Olympus Corporation). To confirm the phase transition temperature. After raising the temperature of the film composed of compound (2-6) to 120°C, in the process of cooling down, it was confirmed that the phase transition to the nematic phase at 112°C, the phase transition to the smectic A phase at 110°C, and the phase transition at 94°C It is smectic B phase.

Compound (2-8) (compound represented by the following formula (2-8))

Compound (2-8) was synthesized referring to the synthesis of compound (2-6) described above.

[Measurement of Phase Transition Temperature]

The phase transition temperature of the compound (2-8) was confirmed by the same method as the measurement of the phase transition temperature of the compound (2-6). After raising the temperature of compound (2-8) to 140°C, in the process of cooling down, it was confirmed that the phase transition was nematic phase at 131°C, the phase transition was smectic A phase at 80°C, and the phase transition was smectic phase at 68°C. Phase B.

Example 1

[Preparation of Polarizing Film Forming Composition]

The following components were mixed and stirred at 80° C. for 1 hour to obtain a composition for forming a polarizing film.

Polymeric smectic liquid crystal compound: 75 parts of compound (2-6)

Compound (2-8) 25 parts

Azo pigment (1): 2.5 parts of compound (1-8)

D10 pigment described in Japanese Patent Laid-Open No. 8-278409

Polymerization initiator: 2-dimethylamino-2-benzyl-1-(4-morpholine phenyl)-1-butanone (Irugakyua 369: manufactured by Ciba Specialty Chemicals Co., Ltd. )

6 servings

Leveling agent: polyacrylate compound (BYK-361N: manufactured by BYK-Chemie) 1.2 parts

Solvent: 250 parts of cyclopentanone

[Measurement of Phase Transition Temperature]

Compound (2-6) and compound (2-8) were mixed at a mass ratio of 75 parts: 25 parts.

As in the case of compound (2-6) and compound (2-8), the phase transition temperature of the prepared mixture was obtained as described above. After raising the temperature of the mixture to 140°C, it was confirmed that the phase transition was to a nematic phase at 115°C, to a smectic A phase at 105°C, and to a smectic B phase at 75°C during cooling down.

[Manufacturing and evaluation of this polarizing film]

1. Forming an alignment film

A glass substrate was used as the transparent substrate.

A 2% by mass aqueous solution (orientable polymer composition) of polyvinyl alcohol (polyvinyl alcohol 1000 complete saponification type, manufactured by Wako Pure Chemical Industries, Ltd.) was applied on the glass substrate by spin coating, and dried to form A film with a thickness of 100 nm. Next, an alignment film was formed by subjecting the surface of the obtained film to rubbing treatment. The rubbing process uses a semi-automatic rubbing device (trade name: LQ-008 type, manufactured by Changyang Engineering Co., Ltd.), through a cloth (trade name: YA-20-RW, manufactured by Yoshikawa Chemical Co., Ltd.), at a pressure distance of 0.15mm and a rotation speed of 500rpm , 16.7mm/s conditions. By this rubbing treatment, a laminate 1 in which an alignment film was formed on a glass substrate was obtained.

2. Form polarizing film

The above-mentioned composition for forming a polarizing film is coated on the alignment film of the laminate 1 by a spin coating method, heated and dried on a hot plate at 120° C. for 3 minutes, and then rapidly cooled to room temperature to form a dry layer on the above-mentioned alignment film. film. In this dry film, the liquid crystal state of the polymerizable smectic liquid crystal compound is the smectic B phase. Next, by using a UV irradiation device (SPOTCURE SP-7: manufactured by Usio Electric Co., Ltd.), the dried film was irradiated with ultraviolet light at an exposure dose of 2400 mJ/cm ² (365 nm basis), and the polymerizable smectic liquid crystal contained in the dry film The compound is polymerized while maintaining the liquid crystal state, and the polarizing film is formed from the dried film. When the thickness of the polarizing film at this time was measured with a laser microscope (OLS3000 by Olympus Corporation), it was 1.7 micrometers.

3. X-ray diffraction measurement

The polarizing film of the obtained laminated body 2 was subjected to X-ray diffraction measurement using an X-ray diffractometer X'Pert PRO MPD (manufactured by Spectris Co., Ltd.). Using Cu as a target, the X-rays produced under the conditions of X-ray tube current 40mA and X-ray tube voltage 45kV pass through the fixed divergence slit 1/2 ° along the rubbing direction (the friction of the alignment film under the polarizing film is obtained in advance). direction) incident, scanning with a scanning range of 2θ=4.0 to 40.0° and a step width of 2θ=0.01671°, the measurement results showed that a sharp half-width (FWHM) of about 0.312° was obtained near 2θ=20.08° Diffraction peaks. In addition, the same results were obtained from the incidence perpendicular to the rubbing direction. The lattice period (order period) (d) obtained from the position of the peak is approximately It can be seen that a structure reflecting a higher order smectic phase is formed.

4. Determination of dichroic ratio

In order to confirm the usefulness of this polarizer, the dichroic ratio was measured as follows.

Using a spectrophotometer (UV-3150 manufactured by Shimadzu Corporation) equipped with a folder with a polarizer, the absorbance (A ¹ ) and the absorbance of the maximum absorption wavelength in the direction of the transmission axis were measured by the two-ray method. Absorbance in axial direction (A ² ). The reference side of the folder is provided with a mesh that reduces the amount of light by 50%. The ratio (A ² /A ¹ ) was calculated from the measured values of absorbance (A ¹ ) in the direction of the transmission axis and absorbance (A ² ) in the direction of the absorption axis, and was defined as a dichroic ratio. The results are shown in the table. The higher the dichroic ratio, the more useful it is as a polarizing film. Table 1 shows the maximum absorption wavelength of the absorbance (A ² ) in the direction of the absorption axis and the measurement results of the dichroic ratio at this wavelength.

Embodiment 2～9 and comparative example 1～3, reference example 1～4 all changed the kind of azo pigment (1), other make polarizing film identically with embodiment 1, measure the absorbance (A ² ) The maximum absorption wavelength λMAX and the dichroic ratio at this wavelength. The results are shown in Table 1.

【Table 1】

Example 10

Use compound (2-14) to replace compound (2-6) as polymerizable smectic liquid crystal compound, use compound (2-24) to replace compound (2-8), other all form polarizing film identically with embodiment 1 , and its dichroic ratio at λMAX=518nm is 36.

Example 11

Use compound (2-14) to replace compound (2-6) as polymerizable smectic liquid crystal compound, use compound (2-24) to replace compound (2-8), other all form polarizing film identically with embodiment 2 , and its dichroic ratio at λMAX=392nm is 22.

Example 12

Use compound (2-14) to replace compound (2-6) as polymerizable smectic liquid crystal compound, use compound (2-24) to replace compound (2-8), other all form polarizing film identically with embodiment 3 , and its dichroic ratio at λMAX=536nm is 40.

Example 13

[Preparation of Polarizing Film Forming Composition]

The following components were mixed and stirred at 80° C. for 1 hour to obtain a composition for forming a polarizing film.

Polymeric smectic liquid crystal compound: 75 parts of compound (2-6)

Compound (2-8) 25 parts

Azo pigment (1): 2.5 parts of compound (1-8)

Polymerization initiator: 6 parts of 2-dimethylamino-2-benzyl-1-(4-morpholinephenyl)-1-butanone (Irgakyua 369: manufactured by Ciba Specialty Chemicals Co., Ltd.)

Leveling agent: polyacrylate compound (BYK-361N: manufactured by BYK-Chemie) 1.2 parts

Solvent: 250 parts of cyclopentanone

〔Production of photo-alignment film on retardation film〕

Using a retardation film (uniaxially stretched film WRF-S (modified polycarbonate resin), retardation value 137.1nm, thickness 50μm, manufactured by Teijin Chemicals Co., Ltd.) as a transparent substrate, apply by bar coating method A solution (composition for forming a photo-alignment film) obtained by dissolving 5% of a photo-alignment polymer of the following formula (3) in cyclopentanone was dried at 120° C. to obtain a dry film. On the dried film, polarized light UV was irradiated in a direction of 45° with respect to the slow axis of the retardation film to obtain a photo-alignment film. The polarized UV treatment was performed using a UV irradiation device (SPOT CURE SP-7: manufactured by Usio Electric Co., Ltd.), under the condition that the intensity measured at a wavelength of 365 nm was 100 mJ.

〔Production of circular polarizing plate〕

The composition for forming a polarizing film was coated on a photo-alignment film by a bar coating method, heated and dried in a drying oven at 120° C. for 1 minute, and then cooled to room temperature. In this dry film, the liquid crystal state of the polymerizable smectic liquid crystal compound contained is the smectic B phase. Next, by using a UV irradiation device (SPOT CURE SP-7: manufactured by Usio Electric Co., Ltd.), the layer formed by the composition for forming a polarizing film was irradiated with ultraviolet light at an exposure amount of 2400 mJ/cm ² (365 nm standard), and the The polymerizable smectic liquid crystal compound contained in the dry film is polymerized while maintaining the liquid crystal state of the polymerizable smectic liquid crystal compound, and the dry film forms a polarizing film. When the thickness of the polarizing film at this time was measured with a laser microscope (OLS3000 manufactured by Olympus Corporation), it was 1.6 μm.

<Measurement of Optical Properties>

The ellipticity at wavelengths of 450.9 nm, 498.6 nm, 549.4 nm, 587.7 nm, and 627.8 nm was measured for the circularly polarizing plate obtained above, and it was confirmed that almost all wavelengths were circularly polarized light.

450.9 nm = a/b = 0.841

498.6 nm = a/b = 0.889

549.4nm=a/b=0.968

587.7nm=a/b=0.924

627.8nm=a/b=0.852

Industrial Utilization Possibility

The polarizing film is very useful in the manufacture of liquid crystal display devices, (organic) EL display devices and projection type liquid crystal display devices.

Claims (7)

1. a kind of circular polarization light board, successively with polarization film, λ/2 layer and λ/4 layer, and meet following important document (B1), (B2), And (B4) (B3)：

(B1) absorption axiss of the polarization film and the slow axis angulation of λ/2 layer are 15 °；

(B2) slow axis of λ/2 layer and the slow axis angulation of λ/4 layer are 60 °；

(B3) λ/2 layer determined under wavelength 550nm light, the front retardation values of λ/2 layer is 200~300nm's Scope；

(B4) λ/4 layer determined under wavelength 550nm light, the front retardation values of λ/4 layer is 100~150nm's Scope；

The polarization film is as there is the polyazo shown in absorption, following formulas (1) containing the wave-length coverage in 400~800nm Be at least one kind of of pigment and

The composition of polymerism smectic shape liquid-crystal compounds is formed；

The polarization film obtains bragg peak in X-ray diffraction measure；

In formula (1),

N is 1 or 2,

Ar₁And Ar₃The group selected from group shown below is represented independently of one another；

Ar₂Represent the group selected from group shown below；

A₁And A₂The group selected from group shown below is represented independently of one another；

M is 0~10 integer, and when there is 2 m in same group, this 2 m are identical or different each other.

2. a kind of circular polarization light board, with polarization film and λ/4 layer, and meets following important document (A1) and (A2)：

(A1) absorption axiss of the polarization film and the slow axis angulation of λ/4 layer are 45 °；

(A2) scope of the front retardation value of λ/4 layer determined under wavelength 550nm light in 100~150nm；

The polarization film is as there is the polyazo shown in absorption, following formulas (1) containing the wave-length coverage in 400~800nm Be at least one kind of of pigment and

The composition of polymerism smectic shape liquid-crystal compounds is formed；

The polarization film obtains bragg peak in X-ray diffraction measure；

In formula (1),

N is 1 or 2,

Ar₁、Ar₂And Ar₃Represented group is one kind in following 3 kinds combinations：

A₁Represent the group selected from group shown below；

M is 0~10 integer, and when there is 2 m in same group, this 2 m are identical or different each other.

3. circular polarization light board according to claim 1 or 2, wherein, the thickness of the polarization film is more than 1 μm, 5 μm with Under.

4. a kind of organic EL display, possesses the circular polarization light board and organic EL element described in claim 1 or 2.

5. a kind of polarization film, as having how even shown in absorption, following formulas (1) containing the wave-length coverage in 400~800nm Nitrogen system pigment at least one kind of and

The composition of polymerism smectic shape liquid-crystal compounds is formed；

The polarization film obtains bragg peak in X-ray diffraction measure；

In formula (1),

N is 1 or 2,

Ar₁、Ar₂And Ar₃Represented group is one kind in following three kinds combinations：

A₁Represent the group selected from group shown below；

M is 0~10 integer, and when there is 2 m in same group, this 2 m are identical or different each other.

6. a kind of manufacture method of the polarizer, the polarizer possesses polarization film described in claim 5, alignment films and thoroughly successively Bright base material, its manufacture method has following process：

The process for possessing the laminate of the alignment films on the transparent base is got out,

In the alignment films of the laminate, formed containing polymerism smectic shape liquid-crystal compounds, 400~800nm's The process that wave-length coverage has the film of polyazo system pigment shown in the above-mentioned formula (1) of absorption, polymerization initiator and solvent,

The process that the solvent is removed from the film of upper process formation,

The polymerism smectic shape liquid-crystal compounds contained in the film for making to eliminate the solvent turns into smectic shape mesomorphic state Process,

By the polymerism smectic shape liquid-crystal compounds in the case where keeping the form of the smectic shape mesomorphic state, make the polymerization Property the polymerization of smectic shape liquid-crystal compounds, in the process that polarization film is formed in the alignment films.

7. a kind of liquid crystal display device, possesses the polarization film described in claim 5.