TWI724121B - Composition for forming polarizing film and polarizing film - Google Patents

Abstract

The present invention provides a polarizing film forming composition capable of producing a thin and highly transparent polarizing film, and a polarizing film formed from the polarizing film forming composition. The present invention provides a composition for forming a polarizing film that contains a polymerizable liquid crystal compound, a polymerizable non-liquid crystal compound, a dichroic dye, a photopolymerization initiator, and a solvent, and satisfies the following requirements (A) and (B), And a polarizing film formed from the composition for forming a polarizing film. (A) Both the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound have a polymerizable group; (B) the polymerizable liquid crystal compound contained in the coating film obtained from the composition for forming a polarizing film does not form a phase separation state, and shows Out of nematic liquid crystal phase and smectic liquid crystal phase.

Description

Composition for forming polarizing film and polarizing film

The present invention relates to a composition for forming a polarizing film, a polarizing film manufactured from the composition for forming a polarizing film, and a manufacturing method thereof.

In recent years, liquid crystal display devices are strongly required to be thinner, and along with this, the polarizers used in the liquid crystal display devices are also required to be thinner. In order to realize thinner polarizers, the polarizing film used in liquid crystal display devices is being studied to replace the conventional film containing polyvinyl alcohol dyed with iodine by a composition containing a polymerizable liquid crystal compound.

As a polarizing film formed from a composition containing a polymerizable liquid crystal compound, for example, Patent Document 1 discloses a polarizing film composed only of a polymerizable smectic liquid crystal compound, a dichroic dye, a photopolymerization initiator, and an inhibitor. In addition, Patent Document 2 discloses a polarizing film composed only of a polymerizable liquid crystal compound, a dichroic dye, a polymerization initiator, an inhibitor, a gelling agent, and a solvent.

[Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 4719156

[Patent Document 2] Japanese Patent Publication No. 2008-547062

However, the thinning and high transparency of the polarizing film are further required.

The object of the present invention is to provide a polarizing film forming composition capable of producing a thin and highly transparent polarizing film, and a polarizing film formed from the polarizing film forming composition.

The present invention provides the following inventions.

[1] A composition for forming a polarizing film, which contains a polymerizable liquid crystal compound, a polymerizable non-liquid crystal compound, a dichroic dye, a polymerization initiator, and a solvent, and satisfies the following requirements (A) and (B): (A) Both the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound have a polymerizable group; (B) the polymerizable liquid crystal compound contained in the coating film obtained from the composition for forming a polarizing film does not form a phase separation state, and shows Nematic liquid crystal phase and smectic liquid crystal phase; (hereinafter, the necessary conditions for (A) and (B) are referred to as "(required condition A)" and "(required condition B)").

[2] The composition for forming a polarizing film according to [1], wherein the polymerizable liquid crystal compound is a compound represented by formula (1): U ¹ -V ¹ -W ¹ -X ¹ -Y ¹ -X ² -Y ² -X ³ -W ² -V ² -U ² (1)

(In the formula, X ¹ , X ² and X ³ independently represent 1,4-phenylene which may have a substituent or cyclohexane-1,4-diyl which may have a substituent; wherein, X ¹ , At least one of X ² and X ³ is a 1,4-phenylene group which may have a substituent; the -CH ₂ -constituting the cyclohexane-1,4-diyl group may be -O-, -S- or -NR-substitution; R represents an alkyl group or phenyl group with carbon number 1~6; Y ¹ and Y ² 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 of; U ¹ represents a hydrogen atom or a polymerizable group; U ² represents a polymerizable group; W ¹ and W ² independently represent a single bond, -O-, -S-, -COO- or -OCOO-; V ¹ and V ² Each independently represents an alkanediyl group having 1 to 20 carbon atoms that may have a substituent, and -CH ₂ -constituting the alkanediyl group may be substituted with -O-, -S- or -NH-).

[3] The composition for forming a polarizing film according to [1] or [2], wherein the polymerizable non-liquid crystal compound is a monofunctional acrylate or a multifunctional acrylate.

[4] The composition for forming a polarizing film according to any one of [1] to [3], wherein the polymerizable group possessed by the polymerizable liquid crystal compound and the polymerizable group possessed by the polymerizable non-liquid crystal compound are each independently Propylene oxy (CH ₂ =CHCOO-) or methacryloxy (CH ₂ =C(CH ₃ )COO-).

[5] The composition for forming a polarizing film according to any one of [1] to [4], wherein the polymerizable group possessed by the polymerizable liquid crystal compound is the same as the polymerizable group possessed by the polymerizable non-liquid crystal compound.

[6] The composition for forming a polarizing film according to any one of [1] to [5], wherein the polymerizable liquid crystal compound has 1 to 2 polymerizable groups in the molecule, and the polymerizable non-liquid crystal compound has 2 in the molecule. ~6 polymerizable groups.

[7] The composition for forming a polarizing film according to any one of [1] to [6], wherein the content of the polymerizable non-liquid crystal compound is 3 parts by mass or more and 10 parts by mass relative to 100 parts by mass of the polymerizable liquid crystal compound the following.

[8] A method of manufacturing a polarizing film, comprising the following steps (I), (II) and (III): (I) The composition for forming a polarizing film as in any one of [1] to [7] The step of coating on the substrate or the alignment film formed on the substrate to remove the solvent to form a coating film; (II) is to make the polymerizable liquid crystal compound contained in the coating film formed in (I) The step of smectic liquid crystal phase; (III) the step of copolymerizing the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound in the coating film in which the polymerizable liquid crystal compound formed in (II) is in the smectic liquid crystal phase state .

[9] The method for manufacturing a polarizing film as in [8], wherein the substrate is a transparent substrate subjected to alignment treatment.

[10] The method of manufacturing a polarizing film as in [8] or [9], wherein step (II) includes steps (I-1) and step (I-2), and the above step (I-1) is performed Heat treatment until the step (I) Until the polymerizable liquid crystal compound contained in the formed coating film shows a nematic liquid crystal phase, the above step (I-2) is to bring the polymerizable liquid crystal compound formed in step (I-1) into a nematic liquid crystal phase state. The coating film is cooled until the polymerizable liquid crystal compound shows a smectic liquid crystal phase.

[11] A polarizing film manufactured by the manufacturing method of any one of [8] to [10].

[12] The polarizing film as in [11] shows Bragg peaks in the diffraction measurement of X-rays.

[13] A display device comprising the polarizing film as in [11] or [12].

According to the composition for forming a polarizing film of the present invention, a thin and highly transparent polarizing film can be manufactured.

1‧‧‧Transparent substrate

2‧‧‧Optical alignment film

3‧‧‧This polarizing film

4‧‧‧Phase Difference Layer

10‧‧‧Liquid crystal display device

11‧‧‧Anti-reflective layer

12a, 12b‧‧‧polarizing film

13a, 13b‧‧‧Retardation film

14a, 14b‧‧‧Substrate

15‧‧‧Color filter

16‧‧‧Transparent electrode

17‧‧‧Liquid crystal layer

18‧‧‧Interlayer insulation film

19‧‧‧Backlight unit

20‧‧‧Black matrix

21‧‧‧Thin Film Transistor

22‧‧‧Pixel electrode

23‧‧‧Spacer

24‧‧‧LCD device

30‧‧‧EL display device

31‧‧‧Circular Polarizing Plate

33‧‧‧Substrate

34‧‧‧Interlayer insulation film

35‧‧‧Pixel electrode

36‧‧‧Light-emitting layer

37‧‧‧Cathode electrode

38‧‧‧Desiccant

39‧‧‧Sealing cover

40‧‧‧Thin Film Transistor

41‧‧‧Barrier

42‧‧‧Thin Film Sealing Film

100‧‧‧Polarizing Film

110‧‧‧Circular Polarizing Plate

111‧‧‧Light source

112‧‧‧The first lens array

112a‧‧‧lens

113‧‧‧Second lens array

114‧‧‧Polarization conversion element

115‧‧‧Overlapping lens

121、123、132‧‧‧Dichroic mirror

122‧‧‧Mirror

140R, 140G, 140B‧‧‧LCD panel

142, 143‧‧‧ polarized photons

150‧‧‧Heguang 稜鏡

170‧‧‧Projection lens

180‧‧‧Screen

210‧‧‧Volume 1

210A‧‧‧Reel core

211A, 211B‧‧‧coating device

212A, 212B‧‧‧Drying furnace

213A‧‧‧Polarized UV Irradiation Device

213B‧‧‧Light Irradiation Device

220‧‧‧Volume 2

220A‧‧‧Reel core

230‧‧‧Volume 3

230A‧‧‧Core

240‧‧‧Volume 4

240A‧‧‧Reel core

300‧‧‧Supplementary Volume

Fig. 1 is a schematic diagram showing the main part of the continuous manufacturing method (Roll to Roll format) of the polarizing film of the present invention.

2 is a schematic diagram showing the cross-sectional structure of a liquid crystal display device using polarizers containing the polarizing film of the present invention.

Fig. 3 (A1) and (A2) are schematic diagrams showing the stacking sequence of polarizers containing the polarizing film of the present invention provided on a liquid crystal display device.

4(B1) and (B2) are schematic diagrams showing the stacking sequence of polarizers coated with the polarizing film of the present invention, which are provided on a liquid crystal display device.

FIG. 5 is a schematic diagram showing the structure of a liquid crystal display device (in-cell type) using the polarizer containing the polarizing film of the present invention.

6(A) and (B) are schematic cross-sectional views of a circular polarizing plate containing the polarizing film of the present invention.

Fig. 7 is a schematic diagram of a continuous manufacturing method of a circular polarizing plate containing the polarizing film of the present invention.

Figure 8 shows the use of the circular polarizing plate containing the polarizing film of the present invention EL (Electro Luminescence (Electroluminescence) is a schematic diagram of the structure of a display device.

Fig. 9 (C1) and (C2) are schematic diagrams showing the stacking sequence of the circular polarizing plate including the polarizing film of the present invention installed on the EL display device.

Fig. 10 is a schematic diagram showing the structure of an EL display device using a circular polarizing plate containing the polarizing film of the present invention.

FIG. 11 is a schematic diagram showing the structure of a projection type liquid crystal display device using a polarizer containing the polarizing film of the present invention.

<Composition for Polarizing Film Formation>

The composition for forming a polarizing film of the present invention (hereinafter sometimes referred to as "this composition") contains a polymerizable liquid crystal compound, a polymerizable non-liquid crystal compound, a dichroic dye, a polymerization initiator, and a solvent. The polarizing film formed from the composition by the following manufacturing method (hereinafter sometimes referred to as "the polarizing film") can be used to manufacture circular polarizing plates not only suitable for liquid crystal display devices, but also suitable for organic EL display devices (hereinafter referred to as Sometimes called "this circular polarizing plate"). First, the present composition will be explained.

<Polymerizable liquid crystal compound>

The polymerizable liquid crystal compound of the present invention refers to a liquid crystal compound that has a polymerizable group and has the following characteristics: does not form a phase separation state in the coating film formed by the composition, and exhibits a nematic liquid crystal phase and a smectic liquid crystal phase.

Whether the coating film formed from the present composition satisfies (required condition B) can be confirmed as follows, for example. The composition is applied on a glass substrate, and the applied composition is heated and/or reduced in pressure under the condition that the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound are not polymerized, thereby removing the solvent. Then, the coating film formed on the glass substrate is heated to confirm whether the polymerizable liquid crystal compound contained in the coating film does not form a phase separation and shows a nematic liquid crystal phase. Then, the heated coating film is slowly cooled to confirm whether the polymerizable liquid crystal compound contained in the coating film does not form a phase separation and shows a layer Column liquid crystal phase. The confirmation of the nematic liquid crystal phase and the smectic liquid crystal phase can be performed by, for example, texture observation using a polarizing microscope, X-ray diffraction measurement, or differential scanning calorimetry. The confirmation of the formation of phase separation can be performed, for example, by surface observation using various microscopes or scattering degree measurement using a haze meter.

The smectic liquid crystal phase exhibited by the polymerizable liquid crystal compound is more preferably a higher order smectic phase. The so-called higher order smectic phases here refer 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 K phase and smectic L phase, among which smectic B phase, smectic F phase and smectic I phase are more preferable. If the smectic liquid crystal phases shown by the polymerizable liquid crystal compound are these higher order smectic phases, the polarizing film with higher alignment order can be manufactured. In addition, this polarizing film with a higher degree of alignment order can obtain Bragg peaks derived from a higher order structure such as hexagonal liquid phase (hexagonal liquid phase) or crystals in X-ray diffraction measurement.

As the polymerizable liquid crystal compound, a compound having a phase transition temperature of 40 to 200°C from a nematic liquid crystal phase to a smectic liquid crystal phase is preferable, and a compound having a phase transition temperature of 60 to 140°C is more preferable.

As a preferable polymerizable liquid crystal compound, for example, a compound represented by formula (1) (hereinafter sometimes referred to as "compound (1)") is mentioned.

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

[In the formula (1), X ¹ , X ² and X ³ independently represent a 1,4-phenylene group which may have a substituent or a cyclohexane-1,4-diyl group which may have a substituent. Among them, ^{at least one of X 1} , X ² and X ³ is a 1,4-phenylene group which may have a substituent. _{The -CH 2} -constituting the cyclohexane-1,4-diyl group can be substituted with -O-, -S- or -NR-. R represents an alkyl group or phenyl group having 1 to 6 carbon atoms.

Y ¹ and Y ² 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 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 independently represent a single bond, -O-, -S-, -COO-, or -OCOO-.

V ¹ and V ² independently represent an alkanediyl group having 1 to 20 carbon atoms which may have a substituent, and -CH ₂ -constituting the alkanediyl group may be substituted with -O-, -S- or -NH-].

In the compound (1), it is preferable ^{that at least two of X 1} , X ² and X ³ are 1,4-phenylene groups which may have a substituent.

The 1,4-phenylene group which may have a substituent is preferably unsubstituted. Cyclohexane-1,4-diyl which may have substituents is preferably trans-cyclohexane-1,4-diyl which may have substituents, and trans-cyclohexane-1 which may have substituents The ,4-diyl group is preferably unsubstituted.

Examples of the substituent optionally possessed by the 1,4-phenylene group which may have a substituent or the cyclohexane-1,4-diyl group which may have a substituent include: carbon numbers such as methyl, ethyl and butyl 1~4 alkyl group, cyano group, halogen atom, etc.

^{Y 1 of} compound (1) is preferably -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. U ¹ and U ^{2 are} preferably both polymerizable groups, and preferably both are photopolymerizable groups. Here, the so-called photopolymerizable group refers to a group that receives the energy of light and participates in polymerization. The polymerizable liquid crystal compound having a photopolymerizable group is advantageous in that it can be polymerized under lower temperature conditions. As the photopolymerizable group, a radical polymerizable group is preferred. The term "radical polymerizable group" means a group that can participate in a polymerization reaction by active radicals generated from the following polymerization initiator.

In the compound (1), ^{the polymerizable groups of U 1} and U ² may be different from each other, and are preferably the same. Examples of polymerizable groups include vinyl groups, vinyloxy groups, 1-chlorovinyl groups, isopropenyl groups, 4-vinylphenyl groups, acryloxy groups, methacryloxy groups, ethylene oxide groups, and Propylene oxide and so on. Among them, propyleneoxy, methacryloxy and ethyleneoxy are preferred, and propyleneoxy and methacryloxy are more preferred.

Examples of the alkanediyl groups of V ¹ and V ² include: methylene, ethylene, propane-1,3-diyl, butane-1,3-diyl, butane-1,4-diyl , Pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, decane-1,10-diyl , Tetradecane-1,14-diyl and eicosane-1,20-diyl, etc. V ¹ and V ^{2 are} preferably alkanediyl groups having 2 to 12 carbons, and more preferably alkanediyl groups having 6 to 12 carbons.

Examples of the substituent optionally possessed by the alkanediyl group having 1 to 20 carbon atoms which may have a substituent include a cyano group and a halogen atom. The alkanediyl group is preferably unsubstituted, more preferably unsubstituted and straight. Chain-like alkanediyl.

W ¹ and W ^{2 are} preferably a single bond or -O- independently of each other.

As specific examples of the compound (1), compounds represented by the formula (1-1) to the formula (1-23), etc., respectively, can be cited. When the specific example of the compound (1) has a cyclohexane-1,4-diyl group, the cyclohexane-1,4-diyl group is preferably a trans form.

A polymerizable liquid crystal compound can be used in this composition individually or in mixture of 2 or more types. When two or more types are mixed, it is preferable that at least one type is compound (1), and it is more preferable that two or more types are compound (1). As the mixing ratio in the case of mixing two polymerizable liquid crystal compounds, it is usually 1:99-50:50, preferably 5:95-50:50, and more preferably 10:90-50:50.

The polymerization temperature of the composition is usually below the smectic transition temperature of the polymerizable liquid crystal compound. The polymerization temperature of the composition can be controlled by adjusting the components contained in the composition system. It is preferable to obtain the smectic phase transition temperature of the polymerizable liquid crystal compound in advance, and adjust the components other than the polymerizable liquid crystal compound so that the composition is polymerized at a temperature lower than the phase transition temperature. When the composition contains two or more polymerizable liquid crystal compounds, the smectic phase transition temperature of the mixture of the two or more polymerizable liquid crystal compounds is calculated and controlled in the same manner.

Among the exemplified compounds (1), formula (1-2), formula (1-3), formula (1-4), formula (1-6), formula (1-7), formula ( 1-8), the compound represented by the formula (1-13), the formula (1-14) and the formula (1-15). By interacting with other polymerizable liquid crystal compounds or polymerizable non-liquid crystal compounds, these compounds can easily maintain the liquid crystal state of the higher order smectic phase under the temperature conditions below the smectic phase transition temperature. Under the polymerization.

Relative to 100 parts by mass of the solid content of the composition, the content of the polymerizable liquid crystal compound in the composition is usually 70-99.5 parts by mass, preferably 80-99 parts by mass, more preferably 80-94 parts by mass , And more preferably 80 to 90 parts by mass. When the content ratio of the compound (1) is within the above range, the alignment of the following compound (2) tends to increase, which is preferable. Here, the term “solid content” refers to the total amount of the components obtained by removing the solvent from the composition.

The polymerizable liquid crystal compound can be produced by a known method described in, for example, Lub et al. Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996), or Japanese Patent No. 4719156.

<Polymerizable non-liquid crystal compound>

The polymerizable non-liquid crystal compound of the present invention means a compound that has a polymerizable group and does not have a liquid crystal state between a solid and a liquid even if the temperature changes.

The polymerizable non-liquid crystal compound is preferably (i) it is not colored by itself (absorption of visible light), (ii) has compatibility to the extent that it is uniformly mixed with the polymerizable liquid crystal compound, and (iii) does not interfere with the polymerizable liquid crystal The formation of the liquid crystal state shown by the compound.

Examples of polymerizable non-liquid crystal compounds include monofunctional acrylates and polyfunctional acrylics. Enoic acid ester. The term "monofunctional" means having one polymerizable group, and the term "multifunctional" means having multiple polymerizable groups. In terms of continuous progress of the polymerization reaction of the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound, a polyfunctional acrylate is preferred. The number of polymerizable groups possessed by the polymerizable non-liquid crystal compound is preferably 1 to 6, and more preferably 2 to 6.

The polymerizable group possessed by the polymerizable non-liquid crystal compound is preferably the same as the polymerizable group possessed by the polymerizable liquid crystal compound.

Furthermore, when at least one compound selected from a polymerizable liquid crystal compound and a polymerizable non-liquid crystal compound has a plurality of polymerizable groups, preferably at least one polymerizable group possessed by the polymerizable liquid crystal compound and a polymerizable At least one polymerizable group possessed by the non-liquid crystal compound is the same.

As a more preferable polymerizable non-liquid crystal compound, a monomer having the characteristics of (i), (ii) and (iii) above and having 1 to 6, preferably 2 to 6 polymerizable groups in the molecule Functional acrylate and multifunctional acrylate. Furthermore, since the monofunctional acrylate and the multifunctional acrylate are non-liquid crystalline, they are preferably those that do not have a mesogen structure. In addition, within the range of not disturbing the nematic liquid crystal phase and the smectic liquid crystal phase of the polymerizable liquid crystal compound contained in the coating film obtained from the composition, a urethane structure and an amine group may be contained in the molecule. Structure, epoxy structure, glycol structure and polyester structure.

The polymerizable non-liquid crystal compound can be used in the composition alone or in combination of two or more kinds.

The so-called monofunctional acrylate refers to a molecule consisting of an acryloxy group (CH ₂ =CH-COO-) and a methacryloxy group (CH ₂ =C(CH ₃ )-COO-) A compound in the group (hereinafter sometimes referred to as (meth)acryloyloxy). When the polymerizable non-liquid crystal compound is a monofunctional acrylate, the polymerizable liquid crystal compound also preferably has a (meth)acryloyloxy group.

酯等。 Examples of monofunctional acrylates having one (meth)acryloyloxy group include alkyl (meth)acrylates with 4 to 16 carbons, and (meth)acrylic acid with 2 to 14 carbons- β- Carboxyalkyl esters, alkylated phenyl (meth)acrylates with 2 to 14 carbon atoms, methoxy polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, and (Meth) acrylic iso

Ester etc.

The so-called multifunctional acrylate usually refers to a compound having 2 to 6 (meth)acryloxy groups in the molecule. When the polymerizable non-liquid crystal compound is a multifunctional acrylate, the polymerizable liquid crystal compound also preferably has a (meth)acryloyloxy group.

Examples of bifunctional acrylates having two (meth)acryloxy groups include 1,3-butanediol di(meth)acrylate, 1,3-butanediol (meth)acrylate, 1,6-hexanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, Triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol diacrylate, bis(acryloxyethyl) ether of bisphenol A, ethoxy Bisphenol A di(meth)acrylate, propoxylated neopentyl glycol di(meth)acrylate, ethoxylated neopentyl glycol di(meth)acrylate and 3-methylpentadiene Alcohol di(meth)acrylate and the like.

Examples of multifunctional acrylates having 3 to 6 (meth)acryloyloxy groups include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tri(2- Hydroxyethyl) isocyanurate tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate , Pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol tetra(meth)acrylate, tripentaerythritol penta(meth)acrylate, Tripentaerythritol hexa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, tripentaerythritol octa(meth)acrylate; reactant of pentaerythritol tri(meth)acrylate and acid anhydride, dipentaerythritol penta(meth)acrylate ) The reactant of acrylic ester and acid anhydride; the reactant of tripentaerythritol hepta(meth)acrylate and acid anhydride; caprolactone modified trimethylolpropane tri(meth)acrylate, caprolactone modified pentaerythritol Alcohol tri(meth)acrylate, caprolactone-modified tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, caprolactone-modified pentaerythritol tetra(meth)acrylate, caprolactone Lactone modified dipentaerythritol penta(meth)acrylate, caprolactone modified dipentaerythritol hexa(meth)acrylate, caprolactone modified tripentaerythritol tetra(meth)acrylate, caprolactone modified three Pentaerythritol penta(meth)acrylate, caprolactone modified tripentaerythritol hexa(meth)acrylate, caprolactone modified tripentaerythritol hepta(meth)acrylate, caprolactone modified tripentaerythritol octa(meth) ) Acrylate, caprolactone modified pentaerythritol tri(meth)acrylate and acid anhydride reactant, caprolactone modified dipentaerythritol penta(meth)acrylate and acid anhydride reactant, and caprolactone modified three The reactant of pentaerythritol hepta (meth)acrylate and acid anhydride, etc. Furthermore, in the specific examples of the multifunctional acrylate shown here, the so-called (meth)acrylate means acrylate or methacrylate. Also, the so-called caprolactone modification means a ring-opening body or a ring-opening polymer in which caprolactone is introduced between the alcohol-derived part of the (meth)acrylate compound and the (meth)acryloyloxy group .

Commercial products can also be used for this multifunctional acrylate.

Examples of the commercially available products include: A-DOD-N, A-HD-N, A-NOD-N, APG-100, APG-200, APG-400, A-GLY-9E, A-GLY-20E , A-TMM-3, A-TMPT, AD-TMP, ATM-35E, A-TMMT, A-9550, A-DPH, HD-N, NOD-N, NPG, TMPT (manufactured by Shinnakamura Chemical Co., Ltd. ), "ARONIX M-220", "ARONIX M-325", "ARONIX M-240", "ARONIX M-270", "ARONIX M-309", "ARONIX M-310", "ARONIX M-321", " ARONIX M-350", "ARONIX M-360", "ARONIX M-305", "ARONIX M-306", "ARONIX M-450", "ARONIX M-451", "ARONIX M-408", "ARONIX M-400", "ARONIX M-402", "ARONIX M-403", "ARONIX M-404", "ARONIX M-405", "ARONIX M-406" (manufactured by Toagosei Co., Ltd.), "EBECRYL 11", "EBECRYL 145", "EBECRYL 150", "EBECRYL 40", "EBECRYL 140", "EBECRYL 180", DPGDA, HDDA, TPGDA, HPNDA, PETIA, PETRA, TMPTA, TMPEOTA, DPHA, EBECRYL series (made by Daicel-Cytec Co., Ltd.), etc.

As a preferable polyfunctional acrylate, the compound represented by following formula (4-1)-(4-14), respectively, is mentioned.

Relative to the total mass of the composition, the content of the polymerizable non-liquid crystal compound in the composition is usually 0.1-20% by mass, preferably 1-10% by mass, more preferably 3-7% by mass. With respect to 100 parts by mass of the solid content of the composition, it is more preferably 0.1-19 parts by mass, still more preferably 1-15 parts by mass, and particularly preferably 4-10 parts by mass. Furthermore, it is particularly preferable that it is 3 parts by mass or more and 10 parts by mass or less with respect to 100 parts by weight of the polymerizable liquid crystal compound. If the content of the polymerizable non-liquid crystal compound is within the above range, the polymerizable component in the composition can be made without disturbing the orientation of the polymerizable liquid crystal compound contained in the coating film obtained from the composition (The polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound) are copolymerized and therefore preferred. The above content also depends on the respective types of the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound. If the content of the polymerizable non-liquid crystal compound is greater than the above range, the transparency of the polarizing film tends to decrease, which is not good.

<Dichroic Pigment>

The so-called dichroic pigments refer to pigments having properties that the absorbance in the long axis direction of the molecule is different from the absorbance in the short axis direction. As long as it has such properties, the dichroic pigment may be a dye or a pigment, or a mixture of plural kinds of compounds.

色素、花青色素、萘色素、偶氮色素及蒽醌色素等，其中，較佳為偶氮色素。作為偶氮色素，可列舉：單偶氮色素、雙偶氮色素、三偶氮色素、四偶氮色素及二苯乙烯偶氮色素等，較佳為雙偶氮色素及三偶氮色素。 As the above-mentioned dichroic dye, one having a maximum absorption wavelength (λMAX) in the range of 300 to 700 nm is preferable. Examples of such dichroic dyes include acridine dyes,

Among pigments, cyanine pigments, naphthalene pigments, azo pigments, anthraquinone pigments, etc., azo pigments are preferred. Examples of azo dyes include monoazo dyes, bisazo dyes, trisazo dyes, tetrasazo dyes, and stilbene azo dyes, and bisazo dyes and trisazo dyes are preferred.

As an azo dye, for example, the compound represented by formula (2) (hereinafter may be referred to as "compound (2)") is mentioned.

A ¹ (-N=NA ² ) _p -N=NA ³ (2)

[In formula (2), A ¹ and A ³ independently represent a phenyl group which may have a substituent, a naphthyl group which may have a substituent, or a monovalent heterocyclic group which may have a substituent. A ² represents an optionally substituted paraphenylene group, an optionally substituted naphthalene-1,4-diyl group, or an optionally substituted divalent heterocyclic group. P represents an integer from 1 to 4. When p is an integer of 2 or more, a plurality of A ² may be the same or different from each other].

唑及苯并

唑等雜環化合物中去掉1個氫原子所得之基。自雜環化合物中去掉2個氫原子所得之基相當於2價雜環基，該雜環化合物之具體例如上所述。 Examples of monovalent heterocyclic groups include quinoline, thiazole, benzothiazole, thienothiazole, imidazole, benzimidazole,

Azole and benzo

A group obtained by removing one hydrogen atom from a heterocyclic compound such as azole. The group obtained by removing two hydrogen atoms from a heterocyclic compound corresponds to a divalent heterocyclic group, and specific examples of the heterocyclic compound are as described above.

As a substituent optionally possessed by the phenyl group, naphthyl group, and monovalent heterocyclic group in ^{A 1} and A ³ , and the p-phenylene group, naphthalene-1,4-diyl ^{group, and divalent heterocyclic group in A 2} Examples include: alkyl groups with 1 to 4 carbon atoms; alkoxy groups with 1 to 4 carbon atoms such as methoxy, ethoxy and butoxy; fluoroalkyl groups with 1 to 4 carbon atoms such as trifluoromethyl; Cyano groups; nitro groups; halogen atoms; substituted or unsubstituted amine groups such as amine groups, diethylamino groups, and pyrrolidinyl groups (the so-called substituted amine group means having 1 or 2 carbon atoms 1~ The amine group of the 6 alkyl group or the two substituted alkyl groups are bonded to each other to form the amine group of the alkanediyl group with 2 to 8 carbon atoms; the unsubstituted amine group is -NH ₂ ). In addition, specific examples of the alkyl group having 1 to 6 carbon atoms are the same as those exemplified in the optional substituents such as the phenylene group of the compound (1).

Among the compounds (2), compounds represented by the following formulas (2-1) to (2-6) are preferred.

[In formulas (2-1)~(2-6), B ¹ to B ²⁰ independently represent a hydrogen atom, an alkyl group with 1 to 6 carbons, an alkoxy group with 1 to 4 carbons, a cyano group, and a nitro group. Group, substituted or unsubstituted amine group (the definitions of substituted amine group and unsubstituted amine group are as described above), chlorine atom or trifluoromethyl group.

n1~n4 represent an integer of 0~3 independently of each other.

When n1 is 2 or more, plural B ² may be the same or different from each other, when n2 is 2 or more, plural B ⁶ may be the same or different from each other, and when n3 is 2 or more, plural B ⁹ may be the same or different from each other, and when n4 is 2 or more, a plurality of B ¹⁴ may be the same or different from each other].

The anthraquinone dye is preferably a compound represented by formula (2-7).

[In formula (2-7), R ¹ to R ⁸ independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom.

R ^x represents an alkyl group with 1 to 4 carbons or an aryl group with 6 to 12 carbons].

色素，較佳為式(2-8)所表示之化合物。 As above

The pigment is preferably a compound represented by formula (2-8).

[In formula (2-8), R ⁹ to R ¹⁵ independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom.

R ^x represents an alkyl group with 1 to 4 carbons or an aryl group with 6 to 12 carbons].

The acridine dye is preferably a compound represented by formula (2-9).

[In formula (2-9), R ¹⁶ to R ²³ independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom.

R ^x represents an alkyl group with 1 to 4 carbons or an aryl group with 6 to 12 carbons].

Examples of the alkyl group having 1 to 4 carbon atoms represented by ^{R x} in formula (2-7), formula (2-8) and formula (2-9) include methyl, ethyl, propyl, and butyl , Pentyl, hexyl, etc. Examples of aryl groups having 6 to 12 carbons include phenyl, tolyl, xylyl, naphthyl, and the like.

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

[In formula (2-10), D ¹ and D ² independently represent a group represented by any one of formula (2-10a) to formula (2-10d).

n5 represents an integer from 1 to 3].

[In formula (2-11), D ³ and D ⁴ independently represent a group represented by any one of formula (2-11a) to formula (2-11h).

n6 represents an integer from 1 to 3].

The content of the dichroic dye in the composition is preferably 0.1 part by mass or more and 30 parts by mass or less, more preferably 0.1 part by mass or more and 20 parts by mass or less, with respect to 100 parts by mass of the content of the polymerizable liquid crystal compound. It is preferably 0.1 part by mass or more and 10 parts by mass or less, and particularly preferably 0.1 part by mass or more and 5 parts by mass or less. If the content of the dichroic dye is within this range, the polymerizable liquid crystal compound can be combined with the polymerizable non-liquid crystal compound without disturbing the alignment of the polymerizable liquid crystal compound contained in the coating film obtained from the composition. The compound is polymerized and is therefore preferred. If the content of the dichroic dye is too large, there is a risk of hindering the alignment of the polymerizable liquid crystal compound. Therefore, the content of the dichroic dye can also be determined within the range in which the polymerizable liquid crystal compound can maintain the liquid crystal state.

Commercially available dichroic pigments can be used.

<Polymerization initiator>

This composition contains a polymerization initiator. The polymerization initiator is a compound capable of initiating a polymerization reaction such as a polymerizable liquid crystal compound. As the polymerization initiator, a photopolymerization initiator capable of generating active radicals by the action of light is preferred.

化合物、錪鹽及鋶鹽等。 As the polymerization initiator, for example, a benzoin compound, a diphenyl ketone compound, an alkyl phenone compound, an acyl phosphine oxide compound, three

Compounds, iodonium salts and sulphur salts, etc.

As the benzoin compound, for example, benzoin, benzoin methyl ether, benzoin Fragrance ether, benzoin isopropyl ether and benzoin isobutyl ether, etc.

Examples of the benzophenone compound include benzophenone, methyl phthalate, 4-phenyl benzophenone, and 4-benzyl-4'-methyl diphenyl sulfide. Ether, 3,3',4,4'-tetra(tert-butylperoxycarbonyl) diphenyl ketone and 2,4,6-trimethyl diphenyl ketone, etc.

啉基-1-(4-甲基噻吩基)丙烷-1-酮、2-苄基-2-二甲胺基-1-(4-

啉基苯基)丁烷-1-酮、2-羥基-2-甲基-1-苯基丙烷-1-酮、1,2-二苯基-2,2-二甲氧基乙烷-1-酮、2-羥基-2-甲基-1-[4-(2-羥基乙氧基)苯基]丙烷-1-酮、1-羥基環己基苯基酮及2-羥基-2-甲基-1-[4-(1-甲基乙烯基)苯基]丙烷-1-酮之低聚物等。 Examples of alkylphenone compounds include diethoxyacetophenone, 2-methyl-2-

Linyl-1-(4-methylthienyl)propane-1-one, 2-benzyl-2-dimethylamino-1-(4-

(Hydroxyphenyl)butan-1-one, 2-hydroxy-2-methyl-1-phenylpropane-1-one, 1,2-diphenyl-2,2-dimethoxyethane- 1-ketone, 2-hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]propane-1-one, 1-hydroxycyclohexylphenyl ketone and 2-hydroxy-2- Oligomers of methyl-1-[4-(1-methylvinyl)phenyl]propan-1-one, etc.

Examples of phosphine oxide compounds include 2,4,6-trimethylbenzyl diphenyl phosphine oxide and bis(2,4,6-trimethylbenzyl) phenyl phosphine oxide. .

化合物，例如可列舉：2,4-雙(三氯甲基)-6-(4-甲氧基苯基)-1,3,5-三

、2,4-雙(三氯甲基)-6-(4-甲氧基萘基)-1,3,5-三

、2,4-雙(三氯甲基)-6-(4-甲氧基苯乙烯基)-1,3,5-三

、2,4-雙(三氯甲基)-6-[2-(5-甲基呋喃-2-基)乙烯基]-1,3,5-三

、2,4-雙(三氯甲基)-6-[2-(呋喃-2-基)乙烯基]-1,3,5-三

、2,4-雙(三氯甲基)-6-[2-(4-二乙胺基-2-甲基苯基)乙烯基]-1,3,5-三

及2,4-雙(三氯甲基)-6-[2-(3,4-二甲氧基苯基)乙烯基]-1,3,5-三

等。 As three

Examples of compounds include: 2,4-bis(trichloromethyl)-6-(4-methoxyphenyl)-1,3,5-tri

, 2,4-bis(trichloromethyl)-6-(4-methoxynaphthyl)-1,3,5-tri

, 2,4-bis(trichloromethyl)-6-(4-methoxystyryl)-1,3,5-tri

, 2,4-bis(trichloromethyl)-6-[2-(5-methylfuran-2-yl)vinyl]-1,3,5-tri

, 2,4-bis(trichloromethyl)-6-[2-(furan-2-yl)vinyl]-1,3,5-tri

, 2,4-bis(trichloromethyl)-6-[2-(4-diethylamino-2-methylphenyl)vinyl]-1,3,5-tri

And 2,4-bis(trichloromethyl)-6-[2-(3,4-dimethoxyphenyl)vinyl]-1,3,5-tri

Wait.

As the polymerization initiator, a commercially available one can be used. Commercially available polymerization initiators include: "Irgacure 907", "Irgacure 184", "Irgacure 651", "Irgacure 819", "Irgacure 250", and "Irgacure 369" (Ciba-Japan (stock)); "Seikuol BZ", "Seikuol Z", "Seikuol BEE" (Seiko Chemical Co., Ltd.); "Kayacure BP100" (Nippon Kayaku Co., Ltd.); "Kayacure UVI-6992" (manufactured by DOW); "Adeka Optomer" SP-152", "Adeka Optomer SP-170" (ADEKA (shares)); "TAZ-A", "TAZ-PP" (Nihon SiberHegner); And "TAZ-104" (SANWA CHEMICAL company), etc.

The content of the polymerization initiator in the composition can be appropriately adjusted according to the type and amount of the polymerizable liquid crystal compound, and is usually 0.1-30 parts by mass relative to 100 parts by mass of the content of the polymerizable liquid crystal compound. It is preferably 0.5 to 10 parts by mass, more preferably 0.5 to 8 parts by mass. If the content of the polymerization initiator is within this range, the polymerizable liquid crystal compound can be combined with the polymerizable non-liquid crystal compound without disturbing the alignment of the polymerizable liquid crystal compound contained in the coating film obtained from the composition. Copolymerization is therefore preferred.

<Solvent>

This composition contains a solvent. As the solvent, a solvent that can completely dissolve the polymerizable liquid crystal compound, the polymerizable non-liquid crystal compound, and the dichroic dye is preferable. In addition, it is preferably a solvent that is inactive to the polymerization reaction in the composition.

Examples of 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; ethyl acetate, butyl acetate, and ethylene diethyl ether. Ester solvents such as methyl alcohol ether acetate, γ-butyrolactone, or propylene glycol methyl ether acetate and ethyl lactate; acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone and methyl Ketone solvents such as methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; aromatic hydrocarbon solvents such as toluene and xylene; nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran and dimethoxyethane; And chloroform and chlorobenzene and other chlorinated solvents. These solvents can be used alone, or a plurality of them can be used in combination.

The content of the solvent is preferably 50 to 98% by mass relative to the total amount of the composition. In other words, the solid content in the composition is preferably 2-50% by mass. If the solid content is 2% by mass or more, the polarizing film tends to be easily obtained, which is preferable. In addition, if the solid content is 50% by mass or less, the following tendency is preferred: the viscosity of the composition becomes low, so the thickness of the polarizing film becomes substantially uniform, whereby the polarizing film is less likely to be uneven. In addition, the solid content can be determined in consideration of the thickness of the polarizing film to be manufactured.

The composition may also contain ingredients other than the above-mentioned ingredients, as the ingredient, especially Examples include polymerization reaction aids that control the polymerization reaction of polymerizable liquid crystal compounds and the like.

<Polymerization Auxiliary>

酮及9-氧硫

等

酮化合物(例如2,4-二乙基-9-氧硫

、2-異丙基-9-氧硫

等)；蒽及含烷氧基之蒽(例如二丁氧基蒽等)等蒽化合物；酚噻

及紅螢烯等。 The composition may further contain a sensitizer. As the sensitizer, a photosensitizer is preferred. As the sensitizer, for example:

Ketone and 9-oxysulfur

Wait

Ketone compounds (e.g. 2,4-diethyl-9-oxysulfur

, 2-isopropyl-9-oxysulfur

Etc.); anthracene compounds such as anthracene and alkoxy-containing anthracene (such as dibutoxyanthracene, etc.); phenothi

And red fluorene and so on.

When the composition contains a sensitizer, the polymerization reaction of the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound contained in the composition can be further promoted. The amount of the sensitizer used is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 10 parts by mass, and still more preferably 0.5 to 8 parts by mass relative to 100 parts by mass of the total of the polymerizable liquid crystal compound.

In order to make the polymerization reaction proceed stably, the present composition may contain a polymerization inhibitor as appropriate. By containing the polymerization inhibitor, the progress of the polymerization reaction of the polymerizable liquid crystal compound and the polymerization reaction of the polymerizable non-liquid crystal compound can be controlled.

Examples of the polymerization inhibitor include hydroquinone, alkoxy-containing hydroquinone, alkoxy-containing catechol (for example, butylcatechol, etc.), pyrogallol, Radical scavengers such as 2,2,6,6-tetramethyl-1-piperidinyloxy radicals; thiophenols; β-naphthylamines and β-naphthols, etc.

When the polymerization inhibitor is contained in the composition, the content of the polymerization inhibitor is preferably 0.1-30 parts by mass, more preferably 0.5-10 parts by mass relative to 100 parts by mass of the polymerizable liquid crystal compound. , And more preferably 0.5 to 8 parts by mass. If the content of the polymerization inhibitor is within this range, the polymerization can be carried out without disturbing the alignment of the polymerizable liquid crystal compound contained in the composition for forming a polarizing film. Therefore, the polymerizable liquid crystal compound can be made more favorable. Polymerize while maintaining the liquid crystal state.

<Leveling Agent>

The present composition preferably contains a leveling agent. The so-called leveling agent refers to the function of adjusting the fluidity of the composition and making the coating film obtained by coating the composition flatter Those include surfactants and the like. The leveling agent is more preferably at least one selected from the group consisting of a leveling agent mainly composed of a polyacrylate compound and a leveling agent mainly composed of a compound containing a fluorine atom. In addition, the polyacrylate compound referred to herein does not have a polymerizable group.

As a leveling agent with polyacrylate compound as the main component, examples include: "BYK-350", "BYK-352", "BYK-353", "BYK-354", "BYK-355", "BYK- 358N", "BYK-361N", "BYK-380", "BYK-381" and "BYK-392" [BYK Chemie Company], etc.

As a leveling agent with a fluorine atom-containing compound as the main component, examples include "MEGAFAC R-08", "MEGAFAC R-30", "MEGAFAC R-90", "MEGAFAC F-410", and "MEGAFAC F- 411", "MEGAFAC F-443", "MEGAFAC F-445", "MEGAFAC F-470", "MEGAFAC F-471", "MEGAFAC F-477", "MEGAFAC F-479", "MEGAFAC F-482" "And "MEGAFAC F-483" [DIC (shares)]; "Surflon S-381", "Surflon S-382", "Surflon S-383", "Surflon S-393", "Surflon SC-101", "Surflon SC-105", "KH-40" and "SA-100" [AGC Seimi Chemical (stock)]; "E1830", "E5844" [Daikin Fine Chemical Research Institute (stock)]; "Eftop EF301", "Eftop EF303", "Eftop EF351" and "Eftop EF352" [Mitsubishi Materials Electronic Chemicals (stock)] etc.

When the composition contains a leveling agent, the content is preferably 0.3 parts by mass or more and 5 parts by mass or less, and more preferably 0.5 parts by mass or more and 3 parts by mass or less with respect to 100 parts by mass of the polymerizable liquid crystal compound. If the content of the leveling agent is within the above-mentioned range, there is a tendency that the polymerizable liquid crystal compound is easily aligned horizontally and the obtained polarizing film becomes smoother, which is preferable. If the content of the leveling agent with respect to the polymerizable liquid crystal compound exceeds the above-mentioned range, the obtained polarizing film tends to be uneven, which is not preferable. Furthermore, this The composition may contain two or more leveling agents.

<The method of forming the polarizing film>

Next, the method of forming the polarizing film from the composition will be described. First, the composition is coated on a substrate or an alignment film formed on the substrate. Preferably, it is coated on an alignment film formed on a substrate. As the substrate, a transparent substrate is preferred.

<Transparent substrate>

烯系聚合物等聚烯烴；環狀烯烴系樹脂；聚乙烯醇；聚對苯二甲酸乙二酯；聚甲基丙烯酸酯；聚丙烯酸酯；三乙酸纖維素、二乙酸纖維素及丙酸乙酸纖維素等纖維素酯；聚萘二甲酸乙二酯；聚碳酸酯；聚碸；聚醚碸；聚醚酮；聚苯硫醚及聚苯醚等塑膠。其中，就可容易地自市場上獲得、或透明性優異之方面而言，尤佳為纖維素酯、環狀烯烴系樹脂、聚碳酸酯、聚對苯二甲酸乙二酯或聚甲基丙烯酸酯。就於使用該透明基材製造本偏光膜之情形時，於搬運或保管該透明基材時不會引起破碎等破損而易於操作的方面而言，可預先於該透明基材上貼附支撐基材等。又，有於由本偏光膜製造圓偏光板時對塑膠基材賦予相位差性之情況，將於下文進行說明。於該情形時，只要藉由延伸處理等對塑膠基材賦予相位差性即可。再者，對透明基材賦予相位差性之方法將於下文中進行說明。 The so-called transparent substrate is a substrate having transparency to the extent that light, especially visible light, can pass through. The so-called transparency refers to the characteristic that the transmittance of light with wavelengths from 380 to 780 nm is above 80%. Specifically, if the transparent substrate is exemplified, a glass substrate or a plastic substrate can be exemplified. Furthermore, as the plastic that constitutes the plastic base material, for example, polyethylene, polypropylene, plastic

Polyolefins such as olefin polymers; cyclic olefin resins; polyvinyl alcohol; polyethylene terephthalate; polymethacrylate; polyacrylate; cellulose triacetate, cellulose diacetate, and acetic acid propionate Cellulose esters such as cellulose; polyethylene naphthalate; polycarbonate; poly sulfide; polyether sulfide; polyether ketone; polyphenylene sulfide and polyphenylene ether and other plastics. Among them, cellulose ester, cyclic olefin resin, polycarbonate, polyethylene terephthalate, or polymethacrylic acid are particularly preferred in terms of being easily available on the market or having excellent transparency. ester. In the case of using the transparent substrate to manufacture the polarizing film, it is easy to handle without causing breakages such as breakage when the transparent substrate is transported or stored, and a support base can be attached to the transparent substrate in advance. Materials and so on. In addition, there are cases where phase difference is imparted to the plastic substrate when the circular polarizing plate is manufactured from the polarizing film, which will be described below. In this case, it is only necessary to impart retardation to the plastic substrate by stretching treatment or the like. Furthermore, the method of imparting retardation to the transparent substrate will be described below.

The cellulose ester-based cellulose contains at least a part of the hydroxyl group esterified with acetic acid. Cellulose ester films containing such cellulose esters are easily available on the market. Examples of commercially available cellulose triacetate films include "Fujitac Film" (Fuji Film Co., Ltd.); "KC8UX2M", "KC8UY" and "KC4UY" (Konica Minolta Opto Co., Ltd.) Wait. Such a commercially available cellulose triacetate film can be used as a transparent substrate directly or after imparting retardation as necessary. In addition, it can also be used as a transparent substrate after performing surface treatments such as anti-glare treatment, hard coating treatment, antistatic treatment, or anti-reflection treatment on the surface of the prepared transparent substrate.

烯或多環降

烯系單體等環狀烯烴之聚合物或共聚物(環狀烯烴系樹脂)所構成者，該環狀烯烴系樹脂可局部地含有開環部。又，亦可為將含有開環部之環狀烯烴系樹脂氫化而成者。進而，就不明顯損及透明性之方面、或不明顯增大吸濕性之方面而言，該環狀烯烴系樹脂亦可為例如環狀烯烴與鏈狀烯烴或乙烯基化芳香族化合物(苯乙烯等)之共聚物。又，該環狀烯烴系樹脂亦可於其分子內導入極性基。 The so-called cyclic olefin resin, for example, refers to

Alkene or polycyclic drop

A polymer or copolymer (cyclic olefin-based resin) of a cyclic olefin such as an olefin-based monomer, and the cyclic olefin-based resin may partially contain a ring-opening part. Moreover, it may be what hydrogenated the cyclic olefin resin containing a ring-opening part. Furthermore, in terms of not significantly impairing transparency or not significantly increasing hygroscopicity, the cyclic olefin resin may be, for example, cyclic olefin and chain olefin or vinylated aromatic compound ( Copolymers of styrene, etc.). In addition, the cyclic olefin-based resin may introduce a polar group into its molecule.

When the cyclic olefin-based 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, etc., and as a vinylated aromatic compound , Is styrene, α-methylstyrene and alkyl substituted styrene, etc. In this copolymer, the content ratio of the structural unit derived from the cyclic olefin relative to all the structural units of the cyclic olefin resin is 50 mol% or less, for example, in the range of about 15-50 mol%. When the cyclic olefin resin is a terpolymer obtained from a cyclic olefin, a chain olefin, and a vinylated aromatic compound, for example, the total structural unit of the cyclic olefin resin is derived from the chain The content of structural units of olefins is about 5 to 80 mol%, and the content of structural units derived from vinylated aromatic compounds is about 5 to 80 mol%. The cyclic olefin resin of the terpolymer has the advantage of relatively reducing the amount of expensive cyclic olefin used in the production of the cyclic olefin resin.

Cyclic olefin resins are easily available on the market. Examples of commercially available cyclic olefin resins include: "Topas" [Ticona Corporation (Germany)]; "ARTON" [JSR (shares)]; "ZEONOR" and "ZEONEX" [Japan ZEON (shares)]; APEL" [Mitsui Chemicals Co., Ltd.], etc. Can be achieved by, for example, solvent casting or melt extrusion A well-known film forming method, such as a method, forms such a cyclic olefin-based resin into a film to form a film (cyclic olefin-based resin film). In addition, a cyclic olefin resin film that is commercially available in the form of a film can also be used. As the above-mentioned commercially available cyclic olefin resin film, for example, "S-SINA" and "SCA40" [Sekisui Chemical Industry Co., Ltd.]; "ZEONOR film" [Optronics (stock)]; "ARTON film" [ JSR (shares)] and so on.

Then, the method of imparting retardation to the plastic substrate is briefly described. The plastic substrate can be imparted with retardation by a well-known stretching method. For example, a roll (winding body) formed by winding a plastic base material on a roller is prepared, the plastic base material is continuously rolled out from the winding body, and the rolled plastic base material is transported into a heating furnace. The setting temperature of the heating furnace is set to the range of near the glass transition temperature of the plastic substrate (℃)~[glass transition temperature+100](℃), preferably set to near the glass transition temperature (℃)~[glass transition temperature +50] (℃) range. In the heating furnace, when extending in the direction of the plastic base material or in a direction orthogonal to the direction of progress, the conveying direction or tension is adjusted, and it is inclined at an arbitrary angle to perform uniaxial or biaxial thermal stretching. The extension magnification is usually in the range of about 1.1 to 6 times, preferably in the range of about 1.1 to 3.5 times. In addition, the method of extending in the inclined direction is not particularly limited as long as the alignment axis can be continuously inclined to a desired angle, and a known extending method can be used. The above-mentioned extension method includes, for example, the method described in Japanese Patent Laid-Open No. 50-83482 or Japanese Patent Laid-Open No. 2-113920.

The thickness of the transparent substrate is preferably thinner in terms of the weight to be practically operable and to ensure sufficient transparency. However, if it is too thin, the strength will decrease and the workability will tend to be poor. . The appropriate thickness of the glass substrate is, for example, about 100 to 3000 μm, preferably 100 to 1000 μm. The appropriate thickness of the plastic substrate is, for example, about 5 to 300 μm, preferably 20 to 200 μm. When the polarizing film is used as the following circular polarizing plate, especially when used as a circular polarizing plate for mobile devices, the thickness of the transparent substrate is preferably thinner, and the thickness of the glass substrate It is preferably about 100 to 500 μm, and in the case of a plastic substrate, the thickness is preferably about 20 to 100 μm. Furthermore, by extending When the plastic substrate imparts phase difference, the thickness after stretching is determined according to the thickness before stretching or the stretching ratio.

<Alignment film>

It is preferable to form an alignment film on the substrate used for manufacturing the polarizing film. In this case, the composition is coated on the alignment film. Therefore, the alignment film preferably has solvent resistance to the extent that it will not be dissolved due to coating of the composition or the like. Furthermore, it is preferable to have heat resistance in heat treatment for removing solvents or aligning liquid crystals. As the alignment film, an alignment polymer can be used.

唑、聚伸乙亞胺、聚苯乙烯、聚乙烯吡咯啶酮、聚丙烯酸或聚丙烯酸酯類等聚合物。該等之中，較佳為聚乙烯醇。形成配向膜之該等配向性聚合物可單獨使用，亦可混合使用2種以上。 Examples of the above-mentioned alignment polymers include: polyamides or gelatins having an amide bond in the molecule, polyimines having an amide bond in the molecule, and polyamides and polyethylene as hydrolysates thereof. Alcohol, alkyl modified polyvinyl alcohol, polypropylene amide, poly

Azole, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid or polyacrylates and other polymers. Among them, polyvinyl alcohol is preferred. The alignment polymers forming the alignment film may be used alone, or two or more of them may be mixed and used.

The alignment polymer is coated on the substrate in the form of an alignment polymer composition (a solution containing the alignment polymer) dissolved in a solvent, thereby forming an alignment film on the substrate. Examples of the solvent include: water; alcohol solvents such as methanol, ethanol, ethylene glycol, isopropanol, propylene glycol, methyl siloxol, butyl siloxol, and propylene glycol monomethyl ether; ethyl acetate and 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, cyclopentanone, cyclohexanone, methyl pentanone And ketone solvents such as methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; aromatic hydrocarbon solvents such as toluene and xylene, nitrile solvents such as acetonitrile; ethers such as tetrahydrofuran and dimethoxyethane Solvents; chloroform and chlorobenzene and other hydrocarbon solvents substituted with chlorine. These organic solvents can be used alone, or a plurality of them can be used in combination.

In addition, as the alignment polymer composition used to form the alignment film, commercially available alignment film materials can also be used directly. As a commercially available alignment film material, one can include: Sunever (Note Registered trademark, manufactured by Nissan Chemical Industry Co., Ltd. or Optomer (registered trademark, manufactured by JSR (Stock)), etc.

As a method of forming an alignment film on the substrate, for example, the alignment polymer composition or a commercially available alignment film material can be coated on the substrate, and then annealed, thereby forming an alignment on the substrate. membrane. The thickness of the alignment film thus obtained 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 alignment restricting force to the above-mentioned alignment film, it is preferable to perform rubbing (rubbing method) as necessary. By imparting an alignment restriction force, the polymerizable liquid crystal compound can be aligned in a desired direction.

As a method of imparting the alignment restriction force by the friction method, for example, the following method is exemplified: preparing a friction roller wound with a friction cloth and rotating, and placing a laminate on a base with a coating film for forming an alignment film on a table , Conveying to the rotating rubbing roller, thereby bringing the coating film for forming the alignment film into contact with the rotating rubbing roller.

In addition, a so-called photo-alignment film can also be used. The so-called photo-alignment film generally refers to coating a composition containing a polymer or monomer having a photoreactive group and a solvent (hereinafter sometimes referred to as the "composition for forming a photo-alignment layer") on a substrate, by The photo-alignment inducing layer is formed on the substrate, and the photo-alignment inducing layer is given an alignment restriction force by irradiating polarized light (preferably polarized light UV) to form an alignment film of the photo-alignment layer. The so-called photoreactive group refers to a group that generates liquid crystal alignment ability by irradiating light (light irradiation). Specifically, it refers to a light reaction that is the origin of the alignment ability of liquid crystals, such as induction of molecular alignment or isomerization reaction, dimerization reaction, photocrosslinking reaction, or photolysis reaction caused by irradiation of light. . Among the photoreactive groups, those that cause a dimerization reaction or a photocrosslinking reaction are preferable in terms of excellent alignment and maintaining the smectic liquid crystal state when the polarizing film is formed. As the photoreactive group that can cause the reaction as described above, it is preferably one having an unsaturated bond, especially a double bond, and particularly preferably one having a carbon-carbon double bond (C=C bond), carbon-nitrogen double bond A group consisting of at least one bond (C=N bond), nitrogen-nitrogen double bond (N=N bond), and carbon-oxygen double bond (C=O bond).

Examples of the photoreactive group having a C=C bond include vinyl, polyalkenyl, stilbene, stilbazolium, stilbazolium, chalcone, and cinnamyl, etc. . Examples of the photoreactive group having a C=N bond include groups having structures such as aromatic Schiff bases and aromatic hydrazones. Examples of photoreactive groups having N=N bonds include: azophenyl, azonaphthyl, aromatic heterocyclic azo, bisazo, formazan, etc., or azooxybenzene For the basic structure. As a photoreactive group which has a C=O bond, a diphenyl ketone group, a coumarin group, an anthraquinone group, a maleimide group, etc. are mentioned. These groups may have substituents such as an alkyl group, an alkoxy group, an aryl group, an allyloxy group, a cyano group, an alkoxycarbonyl group, a hydroxyl group, a sulfonic acid group, and a halogenated alkyl group.

Among them, the photoreactive group that can cause photodimerization is preferred, and the cinnamon group and the chalcone group have relatively small amount of polarized light required for easy photo-alignment, and are excellent in thermal stability or stability over time. The photo-alignment layer is therefore preferred. In addition, as a polymer having a photoreactive group, it is particularly preferable that the end portion of the side chain of the polymer has a cinnamon base forming a cinnamic acid structure.

The solvent of the composition for forming a photo-alignment layer is preferably one that dissolves a polymer and a monomer having a photoreactive group. Examples of the solvent include the solvents used in the above-mentioned aligning polymer composition.

With respect to the composition for forming a photo-alignment layer, the concentration of the polymer or monomer having a photoreactive group can be determined according to the type of the polymer or monomer having the photoreactive group or the thickness of the photo-alignment film to be manufactured Appropriate adjustment, expressed in terms of the solid content concentration, is preferably set to at least 0.2% by mass, and particularly preferably in the range of 0.3-10% by mass. In addition, the composition may also contain a polymer material such as polyvinyl alcohol or polyimide or a photosensitizer within a range that does not significantly impair the characteristics of the photo-alignment film.

As a method for coating the composition for forming a photo-alignment layer on a substrate, coating methods such as spin coating, extrusion coating, gravure coating, die coating, bar coating, and applicator method can be used , Or known methods such as flexographic printing and other printing methods. Furthermore, by using the following volume When the continuous manufacturing method in roll form is used to manufacture the polarizing film, the coating method is usually a printing method such as a gravure coating method, a die coating method, or a flexographic printing method.

Furthermore, if masking is performed during rubbing or polarized light irradiation, it is also possible to form a plurality of regions (patterns) with different alignment directions.

<The manufacturing method of this polarizing film>

Coating the composition on the above-mentioned substrate or an alignment film formed on the substrate and removing the solvent to obtain a coating film. As the method of coating (coating method), for example, the same methods as those exemplified as the method of coating the aligning polymer or the composition for forming a photo-alignment layer on the substrate can be cited.

Then, the solvent is removed under the condition that the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound contained in the coating film are not polymerized, thereby forming the coating film. As the removal method, for example, a natural drying method, a ventilation drying method, a heat drying method, and a reduced pressure drying method can be cited. Then, the polymerizable liquid crystal composition contained in the coating film is brought into a state showing a smectic liquid crystal phase. In this case, it is preferable to use the characteristics of the polymerizable liquid crystal compound to make its liquid crystal state into a nematic liquid crystal phase, and then convert the nematic liquid crystal phase to a smectic liquid crystal phase. In order to transform the liquid crystal phase in this way, the following method is adopted: first heating to a temperature above the temperature at which the polymerizable liquid crystal compound contained in the coating film shows a nematic liquid crystal phase, and then cooling to a temperature at which the polymerizable liquid crystal compound shows a smectic liquid crystal phase until.

The temperature at which the polymerizable liquid crystal compound in the coating film shows a smectic liquid crystal phase or a nematic liquid crystal phase may be determined in advance by texture observation using the composition as described above.

When polymerizing a polymerizable liquid crystal compound and a polymerizable non-liquid crystal compound, in order to make the polymerizable liquid crystal compound maintain the smectic liquid crystal phase well, it is preferable to use two or more polymerizable liquid crystal compounds as the base of the polymerizable liquid crystal compound combination. If the content ratio of the two or more polymerizable liquid crystal compounds is adjusted to this composition, it has the following advantages: after the smectic liquid crystal phase is formed through the nematic liquid crystal phase, it is convenient for the original crystal display At the temperature of the phase, it can also temporarily form a supercooled state, and it is easy to maintain the liquid crystal state of the higher order smectic phase. In the case of containing two polymerizable liquid crystal compounds, the content ratio of the two polymerizable liquid crystal compounds is usually 1:99-50:50, preferably 5:95-50:50, more preferably 10:90-50: 50.

Next, the polymerization procedure of the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound will be described.

After making the polymerizable liquid crystal compound in the coating film into a smectic liquid crystal phase, the coating film is irradiated with energy while maintaining the smectic liquid crystal phase, thereby polymerizing the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound. Since the composition contains a polymerization initiator, it is preferably irradiated with energy under the conditions for activating the polymerization initiator. As a preferable energy, light can be cited. The light to be irradiated can be based on the type of polymerization initiator contained in the coating film, or the type of polymerizable liquid crystal compound and polymerizable non-liquid crystal compound (especially the type of polymer group contained in the polymerizable liquid crystal compound). ) And its amount, and appropriately performed by light or active electron beam selected from the group consisting of visible light, ultraviolet light and laser light. Among them, ultraviolet light is preferred in terms of easy control of the progress of the polymerization reaction, or in terms of being able to use those widely used in the field as a polymerization device. Therefore, it is preferable to select the types of the polymerizable liquid crystal compound, the polymerizable non-liquid crystal compound, and the polymerization initiator contained in the composition in advance so that the polymerization can be carried out by ultraviolet light. In addition, during polymerization, the coating film can also be cooled by an appropriate cooling method while irradiating ultraviolet light, thereby controlling the polymerization temperature. If the polymerization of the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound can be carried out at a lower temperature by using this cooling method, it will also have the following advantages: even if the above-mentioned base material is relatively low in heat resistance, it can be appropriately formed This polarizing film. Furthermore, during polymerization, the patterned polarizing film can also be obtained by masking or developing.

By performing the polymerization as described above, the polymerizable liquid crystal compound is polymerized while maintaining the smectic phase, preferably the liquid crystal state of the higher order smectic phase as exemplified above, to form the present polarizing film. The polymerizable liquid crystal compound polymerizes while maintaining the liquid crystal state of the smectic phase. The polarizing film obtained by the combination also has the following advantages along with the effect of the above-mentioned dichroic pigment: it is compared with the previous guest-host polarizing film, that is, the polymerizable liquid crystal compound is polymerized while maintaining the liquid crystal state of the nematic phase. Compared with the obtained polarizing film, it has the advantage of higher polarizing performance. Furthermore, there is an advantage that the strength is superior compared to those coated with only dichroic dyes or liquid-tropic liquid crystals.

The thickness of the polarizing film formed in this way is preferably in the range of 0.5 μm or more and 10 μm or less, more preferably 1 μm or more and 5 μm or less. Therefore, the thickness of the coating film for forming the polarizing film is determined in consideration of the thickness of the polarizing film obtained. In addition, the thickness of this polarizing film is determined by measuring with an interference film thickness meter, a laser microscope, or a stylus type film thickness meter.

The transparency can be evaluated by the haze value. The haze value is preferably 5% or less, more preferably 2% or less.

In addition, the polarizing film formed in this way is as described above, and it is particularly preferable to obtain a Bragg peak in X-ray diffraction measurement. As such a polarizing film capable of obtaining the Bragg peak, for example, a polarizing film exhibiting a diffraction peak derived from a hexagonal liquid phase or a crystalline phase can be cited.

<The continuous manufacturing method of the polarizing film>

Above, the outline of the manufacturing method of the polarizing film has been explained. When the polarizing film is manufactured commercially, a method that can continuously manufacture the polarizing film is required. This continuous manufacturing method is based on a roll-to-roll format, and is sometimes referred to as "this manufacturing method." In addition, in this manufacturing method, the case where the base material is a transparent base material is demonstrated centeringly.

This manufacturing method includes, for example, the steps of: preparing the first roll of the transparent substrate to be wound on the first roll core; continuously feeding out the transparent substrate from the first roll; and continuously applying the composition for forming the photo-alignment layer. Distributed on a transparent substrate; remove the solvent from the coated photo-alignment layer forming composition, and continuously form a first coating film on the transparent substrate; The coating film is irradiated with polarized light UV to continuously form a photo-alignment layer to form a photo-alignment film; the composition is continuously coated on the photo-alignment film; polymerizable liquid crystal compounds and polymerizable non-liquid crystal compounds are not polymerized The applied composition is dried under the conditions of, thereby continuously forming a second coating film on the photo-alignment film; making the liquid crystal state of the polymerizable liquid crystal compound contained in the coating film a smectic liquid crystal phase Afterwards, the polymerizable liquid crystal compound is polymerized while maintaining the smectic liquid crystal phase, thereby continuously obtaining a polarizing film; and the continuously obtained laminated body including the transparent substrate, the photo-alignment film and the polarizing film is wound on the second On the core, get the second volume. Here, the manufacturing method will be described with reference to FIG. 1.

The first roll 210 in which the transparent substrate is wound on the first roll core 210A can be easily obtained from the market, for example. As such a transparent substrate that can be obtained on the market in the form of a roll, the transparent substrates exemplified above include cellulose esters, cyclic olefin resins, polycarbonates, and polyethylene terephthalate. Diester or polymethacrylate film, etc. In addition, when the polarizing film is used as a circular polarizing plate, a transparent substrate provided with retardation properties in advance can also be easily obtained from the market, for example, containing cellulose ester, polycarbonate, or cyclic olefin resin The retardation film and so on.

Then, the transparent substrate is sent out from the first roll 210 described above. The method of sending out the transparent substrate is performed by setting an appropriate rotating mechanism on the core 210A of the first roll 210, and using the rotating mechanism to rotate the first roll 210. In addition, it may also be a form in which an appropriate auxiliary roll 300 is set in the direction in which the transparent substrate is sent out from the first roll 210, and the transparent substrate is sent out by the rotation mechanism of the auxiliary roll 300. Furthermore, it may also be a form in which a rotation mechanism is provided on both the first reel core 210A and the auxiliary reel 300, whereby the transparent substrate is fed out while applying proper tension to the transparent substrate.

The transparent substrate sent from the above-mentioned first roll 210 is passed through the coating device 211A by The photo-alignment layer forming composition is coated on the surface by the coating device 211A. The coating device 211A for continuously coating the composition for forming a photo-alignment layer in this manner is usually a printing device capable of coating by gravure coating, die coating, flexographic printing, and the like.

The film passing through the coating device 211A is transported to the drying furnace 212A, and the drying furnace 212A is heated to remove the solvent from the coated composition, and continuously form the first coating film on the transparent substrate . As the drying furnace 212A, for example, a hot-air drying furnace or the like can be used. The setting temperature of the drying oven 212A is determined according to the type of solvent contained in the photo-alignment layer forming composition applied by the coating device 211A, and the like. In addition, the drying furnace 212A may be divided into a plurality of areas and the set temperature of each of the divided areas may be different, or a plurality of drying furnaces may be arranged in series and the set temperature of each of the drying furnaces may be different. The form of drying oven.

The first coating film is continuously formed by the heating furnace 212A and then the surface of the first coating film or the surface of the transparent substrate side is irradiated with polarized UV by the polarized UV irradiation device 213A to form a photo-alignment layer. Optical alignment film.

The laminate of the substrate and the photo-alignment film continuously formed in this way is then passed through the coating device 211B to coat the composition on the photo-alignment film, and then passed through the drying oven 212B to become the content of the composition. The polymerizable liquid crystal compound shows a second coating film of smectic liquid crystal phase. The drying oven 212B plays the role of removing the solvent from the present composition coated on the photo-alignment film, and at the same time also plays the following role: so that the polymerizable liquid crystal compound contained in the present composition is displayed through the nematic liquid crystal phase The smectic liquid crystal phase method imparts thermal energy to the composition. In order to change the polymerizable liquid crystal compound into a nematic liquid crystal phase and then into a smectic liquid crystal phase, the drying oven 212B may be capable of performing multi-stage heating treatment. That is, the drying furnace 212B, like the drying furnace 212A, may be a type of drying furnace that is divided into a plurality of areas and the set temperatures of the divided areas are different, or a plurality of drying furnaces are arranged in series. The setting temperature of each drying furnace is different.

The film passed through the above-mentioned drying oven 212B fully removes the solvent contained in the composition, The polymerizable liquid crystal compound in the second coating film is conveyed to the light irradiation device 213B while maintaining the smectic liquid crystal phase. By the light irradiation of the light irradiation device 213B, the polymerizable liquid crystal compound is photopolymerized together with the polymerizable non-liquid crystal compound while maintaining the smectic liquid crystal phase, and a polarizing film is continuously formed on the photo-alignment film.

The polarizing film continuously formed in this way is wound on the second reel core 220A in the form of a laminate including a transparent substrate and a photo-alignment film, and the second reel 220 is obtained. When winding the formed polarizing film to obtain the second roll, use appropriate spacers for rolls.

In this way, the transparent substrate is passed through the first roll/coating device 211A/drying oven 212A/polarized UV irradiation device 213A/coating device 211B/drying oven 212B/light irradiation device 213B in order, thereby placing the transparent substrate on the transparent substrate. The polarizing film is continuously manufactured on the optical alignment film.

In addition, in the manufacturing method shown in FIG. 1, the method of continuously manufacturing the polarizing film from the transparent substrate is shown. For example, the transparent substrate may be passed through the first roll/coating device 211A/ Drying furnace 212A/polarized UV irradiation device 213A rolls the laminate of the substrate and the photo-alignment film continuously formed by this on the roll core, manufactures the laminate in the form of a roll, and sends the laminate from the roll , The delivered laminate is passed through the coating device 211B/drying furnace 212B/light irradiation device 213B in order to manufacture the polarizing film.

The polarizing film obtained by this manufacturing method is a film-like and elongated shape. When this polarizing film is used in the following liquid crystal display device, etc., it is cut into a desired size according to the scale of the liquid crystal display device and the like, and used.

Above, the structure and manufacturing method of the polarizing film have been explained focusing on the form of the laminate of the transparent substrate/photoalignment film/the polarizing film, but as a laminate containing the polarizing film, it can be peeled off from the laminate The photo-alignment film or the transparent substrate can also be set in a form in which layers or films other than the transparent substrate/photo-alignment film/this polarizing film are laminated. As these layers and films, as described above, the polarizing film may further include a retardation film, or may further include an anti-reflection layer or a brightness enhancement film.

Moreover, it is also possible to make a retardation film by making the transparent substrate itself a retardation film/ Optical alignment film/circular polarizing plate or elliptical polarizing plate in the form of this polarizing film. For example, when a uniaxially stretched quarter-wavelength plate is used as the retardation film, the polarized UV irradiation direction is set to be approximately 45° with respect to the conveying direction of the transparent substrate, thereby enabling the roll-to-roll alignment The circular polarizing plate is made by roll method. As a quarter-wavelength plate used when manufacturing a circularly polarizing plate in this way, it is preferable to have a characteristic that the in-plane retardation value with respect to visible light becomes smaller as the wavelength becomes shorter.

In addition, it is also possible to use a 1/2-wavelength plate as the retardation film to make a linear polarizer roll set so that the retardation axis and the absorption axis of the polarizing film are offset at an angle, on the side opposite to the surface on which the polarizing film is formed Furthermore, a quarter-wavelength plate is formed, thereby making a wide-band circular polarizing plate.

<Use of this polarizing film>

The polarizing film can be used in various display devices. The so-called display device is a device having a display element, which includes a light-emitting element or a light-emitting device as a light-emitting source. As the display device, for example, a liquid crystal display device, an organic electroluminescence (EL) display device, an inorganic electroluminescence (EL) display device, an electron emission display device (such as a field emission display device (FED, Field Emission Display), Surface Conduction Electron Emitter Display (SED), electronic paper (display device using electronic ink or electrophoresis element), plasma display device, projection display device (such as Grating Light Valve (GLV, Grating) Light Valve) display device, display device with digital micro-mirror device (DMD, Digital Micro-mirror Device) and piezoelectric ceramic display, etc. The liquid crystal display device also includes any of a transmissive liquid crystal display device, a semi-transmissive liquid crystal display device, a reflective liquid crystal display device, a direct-view liquid crystal display device, and a projection liquid crystal display device. The display devices can be display devices that display two-dimensional images, or stereoscopic display devices that display three-dimensional images.

The polarizing film is particularly effective for display devices of organic electroluminescence (EL) display devices or inorganic electroluminescence (EL) display devices.

Figures 2 and 5 schematically show a liquid crystal display device using the polarizing film (the following (It is sometimes referred to as "this liquid crystal display device") 10. A schematic view of the cross-sectional structure. The liquid crystal layer 17 is sandwiched by two substrates 14a and 14b.

FIG. 12 is a schematic diagram schematically showing the cross-sectional structure of an EL display device (hereinafter sometimes referred to as "this EL display device") using the polarizing film.

FIG. 13 is a schematic diagram schematically showing the configuration of a projection type liquid crystal display device using the polarizing film.

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

A color filter 15 is arranged on the liquid crystal layer 17 side of the base material 14a. The color filter 15 is arranged at a position opposite to the pixel electrode 22 sandwiching the liquid crystal layer 17, and the black matrix 20 is arranged at a position opposite to the boundary between the pixel electrodes. The transparent electrode 16 is arranged on the side of the liquid crystal layer 17 so as to cover the color filter 15 and the black matrix 20. Furthermore, a protective layer (not shown) may be provided between the color filter 15 and the transparent electrode 16.

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

As the substrate 14a and the substrate 14b, a glass substrate and a plastic substrate can be used. The glass substrate or the plastic substrate can be made of the same material as that exemplified as the transparent substrate used in the production of the polarizing film. In addition, the transparent substrate of the polarizing film may also serve as the substrate 14a and the substrate 14b. When the color filter 15 or the thin film transistor 21 formed on the substrate requires a step of heating to a high temperature, a glass substrate or a quartz substrate is preferred.

The thin film transistor can be the best according to the material of the substrate 14b. Examples of the thin film transistor 21 include: a high-temperature polysilicon transistor formed on a quartz substrate, a low-temperature polysilicon transistor formed on a glass substrate, and an amorphous silicon transistor formed on a glass substrate or a plastic substrate. In order to make the present liquid crystal display device more compact, a driver IC (Integrated Circuit) may be formed on the substrate 14b.

A liquid crystal layer 17 is arranged between the transparent electrode 16 and the pixel electrode 22. A spacer 23 is arranged on the liquid crystal layer 17 to maintain a certain distance between the base material 14a and the base material 14b. Furthermore, in FIG. 2, a columnar spacer is illustrated, but the spacer is not limited to a columnar shape. As long as the base 14a and the base 14b can be kept at a certain distance, the shape is Arbitrary.

On the surfaces of the layers formed on the substrate 14a and the substrate 14b that are in contact with the liquid crystal layer 17, an alignment layer for aligning the liquid crystal in a desired direction can also be respectively arranged. Furthermore, the polarizing film may also be arranged inside the liquid crystal cell, that is, the polarizing film may be arranged on the side of the surface contacting the liquid crystal layer 17. Hereinafter, this form is called "embedded form".

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

Among the substrate 14a and the substrate 14b sandwiching the liquid crystal layer 17, polarizers 12a and 12b are provided on the outer side of the substrate 14a and the substrate 14b, and at least one of these polarizers includes the polarizing film.

Furthermore, it is preferable to laminate retardation layers (for example, a quarter-wave plate or an optical compensation film) 13a and 13b. By arranging the polarizing film on the polarizer 12b among the polarizers 12a and 12b, the liquid crystal display device 10 can be given the function of converting incident light into linear polarized light. Furthermore, depending on the structure of the liquid crystal display device or the type of liquid crystal compound contained in the liquid crystal layer 17, the retardation films 13a and 13b may not be arranged. When the transparent substrate is the retardation film, the polarizing film is used (楕楕) In the case of a circular polarizing plate, the retardation film can be set as a retardation layer, so the retardation layers 13a and/or 13b in FIG. 2 may be omitted. It is also possible to further provide a polarizing film on the light emission side (outer side) of the polarizer containing the polarizing film.

In addition, an anti-reflection film for preventing external light reflection can also be arranged on the outer side of the polarizer containing the polarizing film (when the polarizing film is further provided on the polarizing film, the outer side).

As described above, the polarizing film can be used in the polarizer 12a or 12b of the liquid crystal display device 10 shown in FIG. 2. By disposing the polarizing film on the polarizers 12a and/or 12b, the liquid crystal display device 10 can be made thinner.

When the polarizing film is used for the polarizer 12a or 12b, the stacking order is not particularly limited. The stacking sequence will be described with reference to the enlarged view of the parts A and B surrounded by the dotted line in FIG. 2.

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

Fig. 4 is an enlarged schematic diagram of part B of Fig. 2. (B1) of FIG. 4 is when the polarizer 100 is used as the polarizer 12b, the transparent substrate 1, the optical alignment film 2, and the polarizer 3 are arranged in order from the side of the retardation film 13b. . Figure 4 (B2) is in the case of using the polarizer 100 as the polarizer 12b, the polarizing film 3, the photo-alignment film 2 and the transparent substrate 1 are arranged in order from the side of the retardation film 13b. .

A backlight unit 19 as a light-emitting source is arranged on the outer side of the polarizer 12b. The backlight unit 19 includes a light source, a light guide, a reflection plate, a diffusion sheet, and a viewing angle adjustment sheet. Examples of light sources include electroluminescence, cold cathode tubes, hot cathode tubes, light-emitting diodes (LEDs, Light-Emitting Diodes), laser light sources, mercury lamps, and the like. In addition, the type of the polarizing film can be selected according to the characteristics of the above-mentioned light source.

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 unit 19 is incident into the light guide body, and the path is changed by the reflector and diffused by the diffuser. The diffused light is adjusted to have the required directivity by the viewing angle adjustment sheet, and then enters the polarizer 12b from the backlight unit 19.

Among unpolarized incident light, only a certain linearly polarized light passes through the polarizer of the liquid crystal panel 12b. The linearly polarized light is converted into circularly polarized light or elliptical circularly polarized light by the retardation layer 13b, and sequentially passes through the substrate 14b, the pixel electrode 22, and the like to reach the liquid crystal layer 17.

Here, according to the presence or absence of the potential difference between the pixel electrode 22 and the opposed transparent electrode 16, the alignment state of the liquid crystal molecules contained in the liquid crystal layer 17 changes, and the brightness of the light emitted from the liquid crystal display device 10 is controlled. When the liquid crystal layer 17 is in the alignment state where the polarized light is directly transmitted, the polarized light passes through the liquid crystal layer 17 and the transparent electrode 16, and the light of a certain wavelength range passes through the color filter 15 to reach the polarizer 12a, and the liquid crystal display device The brightest level shows the color determined by the color filter.

Conversely, when the liquid crystal layer 17 is in an alignment state that converts and transmits polarized light, the light passing through the liquid crystal layer 17, the transparent electrode 16 and the color filter 15 is absorbed by the polarizer 12a. As a result, the pixel appears black. In the intermediate alignment state of the two states, the brightness of the light emitted from the liquid crystal display device 10 is also in the middle of the above two states, so the pixel displays an intermediate color.

When the liquid crystal display device 10 is a semi-transmissive liquid crystal display device, it is preferable to use a 1/4 wavelength plate (circular polarizing plate) laminated on the polarizing layer side of the polarizing film. At this time, the pixel electrode 22 has a transmissive portion formed of a transparent material and a reflective portion formed of a material that reflects light. In the transmissive portion, an image is displayed in the same manner as the transmissive liquid crystal display device described above. On the other hand, in the reflecting part, external light enters the liquid crystal display device, and the circularly polarized light passing through the polarizing film passes through the liquid crystal layer 17 through the pixel electrode 22 by the function of the 1/4 wavelength plate provided on the polarizing film. The reflection is used for display.

Next, the EL display device 30 using the polarizing film will be described with reference to FIG. 8. When the polarizing film is used in the EL display device, it is preferable to use the polarizing film as a circular polarizing plate (hereinafter sometimes referred to as "this circular polarizing plate"). This circular polarizing plate usually has two embodiments. Therefore, before describing the structure of the EL display device 30, etc., two embodiments of the circular polarizing plate will be described with reference to FIG. 6.

FIG. 6(A) is a cross-sectional view schematically showing the first embodiment of the circular polarizing plate 110. FIG. In the first embodiment, the main circular polarizing plate 110 in which the retardation layer (retardation film) 4 is further provided on the main polarizing film 3 in the polarizer 100 is used. FIG. 6(B) is a cross-sectional view schematically showing the second embodiment of the circular polarizing plate 110. FIG. In this second embodiment, a transparent substrate 1 (retardation film 4) to which a retardation property is provided in advance is used as the transparent substrate 1 used in the production of the polarizer 100, thereby allowing the transparent substrate 1 itself to serve as the retardation The circular polarizing plate 110 that functions as layer 4.

Here, the manufacturing method of this circular polarizing plate 110 is demonstrated in advance. The second embodiment of the circular polarizing plate 110 is as described above. In the present manufacturing method for manufacturing the present polarizing film 100, a transparent substrate 1 that has been provided with retardation in advance, that is, a retardation film, can be used as a transparent base. Material 1 and manufactured. In the first embodiment of the circular polarizing plate 110, the retardation layer 4 may be formed by bonding a retardation film on the polarizing film 3 manufactured by the manufacturing method B of the present invention. Furthermore, when the polarizing film 100 is manufactured in the form of the second roll 220 by the manufacturing method B, the polarizing film 100 may be rolled out from the second roll 220 and cut into a specific size, and then cut The phase difference film is laminated on the polarizing film 100. The third roll of the phase difference film on the core can also be prepared to continuously manufacture the film-like and elongated circular polarizing plate. 110.

The method of the first embodiment of continuously manufacturing the circularly polarizing plate 110 will be described with reference to FIG. 7. The manufacturing method includes the following steps: continuously unwinding the polarizing film 100 from the second roll 220, and at the same time, continuously unwinding the retardation film from the third roll 230 on which the retardation film is wound; The polarizing layer provided on the polarizing film 100 rolled out in two rolls 220 and the retardation film rolled out from the third roll are continuously bonded to form the circular polarizing plate 110; The circular polarizing plate 110 is wound on the fourth reel core 240A to obtain the fourth reel 240.

Above, the manufacturing method of the first embodiment of the circular polarizing plate 110 has been described, but when bonding the polarizing film 3 and the retardation film in the polarizer 100, an appropriate adhesive can be used The polarizing film 3 and the retardation film are pasted through the adhesive layer formed by the adhesive.

Next, the EL display device provided with the circular polarizing plate 110 will be described with reference to FIG. 8.

In the EL display device 30, an organic functional layer 36 as a light-emitting source and a cathode electrode 37 are laminated on a substrate 33 on which the pixel electrode 35 is formed. A circular polarizing plate 31 is arranged on the side opposite to the organic functional layer 36 while sandwiching the base material 33. As the circular polarizing plate 31, the circular polarizing plate 110 is used. 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 emits light. The organic functional layer 36 as a light-emitting source includes 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 base material 33, and the circular polarizing plate 31 (this circular polarizing plate 110). The organic EL display device including the organic functional layer 36 has been described, and it can also be applied to an inorganic EL display device including an inorganic functional layer.

When manufacturing the EL display device 30, first, a thin film transistor 40 is formed on the substrate 33 in a desired shape. Then, the interlayer insulating film 34 is formed into a film, and then the pixel electrode 35 is formed into a film by a sputtering method, and patterning is performed. Thereafter, an organic functional layer 36 is laminated.

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

When the circular polarizing plate 110 is used as the circular polarizing plate 31, the stacking sequence will be explained with reference to the enlarged view of the part C enclosed by the dotted line in FIG. 8. When the circular polarizing plate 110 is used as the circular polarizing plate 31, the retardation layer 4 on the circular polarizing plate 110 is arranged on the base 33 side. Fig. 9(C1) is an enlarged view of the first embodiment using the circular polarizer 110 as the circular polarizer 31, and Fig. 9(C2) is the second embodiment using the circular polarizer 110 as the circular polarizer 31 Zoom in.

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

Examples of the substrate 33 include ceramic substrates such as sapphire glass substrates, quartz glass substrates, soda glass substrates, and alumina; metal substrates such as copper; plastic substrates, and the like. Although not shown, a thermally conductive film may be formed on the base 33. As a thermally conductive film, a diamond thin film (DLC (Diamond-Like Carbon, diamond-like carbon) etc.) etc. are mentioned. When the pixel electrode 35 is a reflective type, light is emitted in a direction opposite to the substrate 33. Therefore, not only transparent materials can be used, but also non-permeable materials such as stainless steel. The substrate may be formed singly, or a plurality of substrates may be bonded together with an adhesive to form a laminated substrate. In addition, these base materials are not limited to those having a plate shape, 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 arranged at the end of the pixel electrode 35, and its size is about 10-30 μm. Furthermore, the size of the pixel electrode 35 is about 20 μm×20 μm to 300 μm×300 μm.

The wiring electrode of the thin film transistor 40 is provided on the substrate 33. The wiring electrode has a low resistance and has the function of being electrically connected to the pixel electrode 35 and suppressing the resistance to a low value. The wiring electrode usually contains Al, Al and transition metals (not including Ti), Ti or nitride Any one or two or more of titanium (TiN).

An interlayer insulating film 34 is provided between the thin film transistor 40 and the pixel electrode 35. As long as the interlayer insulating film 34 is formed by sputtering or vacuum evaporation of SiO ₂ and other inorganic materials such as silicon oxide and silicon nitride, it is formed by the oxidation of SOG (Spin-On-Glass). Silicon layer, photoresist, polyimide, acrylic resin and other resin-based materials such as coating films that have insulating properties, may be any of them.

The barrier rib 41 is formed on the interlayer insulating film 34. The barrier rib 41 is disposed at the periphery of the pixel electrode 35 (between adjacent pixels). As a material of the barrier rib 41, acrylic resin, polyimide resin, etc. are mentioned. The thickness of the barrier rib 41 is preferably 1.0 μm or more and 3.5 μm or less, more preferably 1.5 μm or more and 2.5 μm or less.

Next, an EL element including 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 to There are less than one hole transport layer and light emitting layer, for example, an electron injection transport layer, a light emitting layer, a hole transport layer, and a hole injection layer in this order.

As the pixel electrode 35, for example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IGZO (Indium Gallium Zinc Oxide, indium gallium zinc oxide), ZnO, SnO ₂ And In ₂ O _3, etc., especially ITO or IZO. The thickness of the pixel electrode 35 only needs to have a thickness greater than a certain level for sufficient hole injection, and it is preferably set to about 10 to 500 nm.

The pixel electrode 35 can be formed by an evaporation method (preferably a sputtering method). The sputtering gas is not particularly limited, as long as it uses inert gases such as Ar, He, Ne, Kr, and Xe, or a mixed gas of these.

As the constituent material of the cathode electrode 37, for example, metal elements such as K, Li, Na, Mg, La, Ce, Ca, Sr, Ba, Al, Ag, In, Sn, Zn, and Zr may be used, but in order to improve the electrode The operation stability is preferably a 2-component or 3-component alloy system selected from the exemplified metal elements. As the alloy system, for example, Ag-Mg (Ag: 1 to 20 at%), Al-Li (Li: 0.3 to 14 at%), In-Mg (Mg: 50 to 80 at%), and Al-Ca (Ca: 5~20at%) etc.

The cathode electrode 37 is formed by an evaporation method, a sputtering method, or the like. Preferably, the thickness of the cathode electrode 37 is 0.1 nm or more, preferably 1 to 500 nm or more.

The hole injection layer has the function of facilitating the injection of holes 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 or a charge transport layer.

The thickness of the light-emitting layer, the combined thickness of the hole injection layer and the hole transport layer, and the thickness of the electron injection and transport layer are not particularly limited, and vary depending on the formation method, but are preferably set to about 5-100 nm. Various organic compounds can be used for 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, in terms of forming a homogeneous thin film, a vacuum evaporation method can be used.

As the luminescence source, the organic functional layer 36 can be used: those that use light emission (fluorescence) derived from singlet excitons, those that use light emission (phosphorescence) derived from triplet excitons, and those that use singlet excitons (phosphorescence) can be used. Layers that emit light (fluorescence) and those that use light emission (phosphorescence) derived from triplet excitons, those formed of organic substances, layers including those formed of organic substances and those formed of inorganic substances, polymer materials, and low-molecular-weight materials Materials, including high-molecular materials and low-molecular materials, etc. However, it is not limited to this, and the organic functional layer 36 using various materials known as EL elements can be used in the EL display device 30 of the present invention.

A desiccant 38 is arranged in the space between the cathode electrode 37 and the sealing cover 39. The reason is that the organic functional layer 36 is not resistant to moisture. The desiccant 38 absorbs moisture to prevent the organic functional layer 36 from deteriorating.

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

As the thin-film sealing film 41, it is preferable to use a DLC film in which DLC (Diamond Like Carbon) is vapor-deposited on the film of the electrolytic capacitor. DLC film has the characteristics of extremely poor moisture permeability and high moisture resistance. In addition, DLC may be directly vapor-deposited on the surface of the cathode electrode 37 to form a DLC film or the like. In addition, a resin film and a metal film may be laminated in multiple layers to form the film sealing film 41.

As described above, the novel polarizing film (this polarizing film) of the present 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 the polarizing film will be described.

Fig. 11 is a schematic diagram showing a projection type liquid crystal display device using the polarizing film.

As the polarizer 142 and/or the polarizer 143 of the projection type liquid crystal display device, the polarizing film is used.

The light beam emitted from a light source (such as a high-pressure mercury lamp) 111 as a light-emitting source first passes through the first lens array 112, the second lens array 113, the polarization conversion element 114, and overlaps the transmission element. The mirror 115 is used to uniformize and polarize the brightness on the cross-section of the reflected light beam.

Specifically, the light beam emitted from the light source 111 is divided into a plurality of micro light beams by the first lens array 112 formed by forming the micro lenses 112a into a matrix. The second lens array 113 and the superimposing lens 115 are provided so that each of the divided light beams irradiates the entire three liquid crystal panels 140R, 140G, and 140B as the illumination object. Therefore, the overall illuminance of the incident side surface of each liquid crystal panel is substantially uniform.

The polarization conversion element 114 is composed of a polarization beam splitter array and is arranged between the second lens array 113 and the superimposing lens 115. The following functions are achieved: the random polarized light from the light source is converted into polarized light with a specific polarization direction in advance, the light loss in the polarized photons on the incident side described below is reduced, and the brightness of the screen is improved.

The light that has been uniformized in brightness and polarized as described above passes through the reflector 122, through the dichroic mirrors 121, 123, and 132 used to separate the three primary colors of RGB, and sequentially passes through the red channel, the green channel, and the blue channel. It is separated and incident on the liquid crystal panels 140R, 140G, and 140B, respectively.

The liquid crystal panels 140R, 140G, and 140B are respectively provided with a polarizer 142 on the incident side, and a polarizer 143 on the exit side. The polarizing film can be used in the polarizer 142 and the polarizer 143.

The polarizer 142 and the polarizer 143 arranged on each optical path of RGB are arranged in such a way that their respective absorption axes are orthogonal. Each of the liquid crystal panels 140R, 140G, and 140B arranged on each optical path has a function of converting the polarization state of each pixel individually controlled according to the image signal into the amount of light.

The polarizing film 100 can be used as a polarizing film with excellent durability in any optical path of the blue channel, the green channel and the red channel by selecting the type suitable for the corresponding channel dichroic pigment.

According to the image data of the liquid crystal panels 140R, 140G, and 140B, the incident light is transmitted through the different transmittance of each pixel, and the optical image produced is synthesized by the light beam 150 and enlarged by the projection lens 170 Projected on the screen 180.

Examples of electronic paper include: display by molecules like optical anisotropy and dye molecular alignment, display by particles like electrophoresis, particle movement, particle rotation, and phase change, and display by the movement of one end of the film Those who perform display, those who display by molecular color/phase change, those who display by molecular light absorption, those who combine electrons and holes to display by self-luminescence, etc. More specifically, examples include: microcapsule type electrophoresis, horizontal movement type electrophoresis, vertical movement type electrophoresis, spherical twisted ball, magnetic twisted ball, cylindrical twisted ball method, charged toner, electronic powder fluid, magnetophoretic type, magnetic Thermal, electrowetting, light scattering (transparency/white turbidity change), cholesteric liquid crystal/photoconductive layer, cholesteric liquid crystal, bistable nematic liquid crystal, ferroelectric liquid crystal, dichromatic dye-liquid crystal dispersion type, movable film , Use leuco dyes for decolorization, photochromism, electronic color rendering, electrodeposition, soft organic EL, etc. Electronic paper can be used not only for personal use of text or images, but also for advertising displays (signs) and so on. With this polarizing film, the thickness of electronic paper can be reduced.

As a stereoscopic display device, for example, a method of arranging different retardation films like a microsphere method (Japanese Patent Laid-Open No. 2002-185983) has been proposed. If the optical film of the present invention is used as a polarizing film, it is easy to use Printing, inkjet, photolithography, etc. are used for patterning, so the manufacturing steps of the display device can be shortened, and the retardation film is not required.

[Example]

Hereinafter, the present invention will be described in further detail with examples. The "%" and "parts" in the examples are mass% and mass parts unless otherwise specified.

In this example, the following polymerizable liquid crystal compound was used.

Compound (1-6) (compound represented by the following formula (1-6))

Compound (1-6) was synthesized by the method described in Lubetal. Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996).

[Determination of phase transition temperature]

The phase transition temperature of the compound (1-6) was confirmed by obtaining the phase transition temperature of the film containing the compound (1-6). The operation is as follows.

A film containing compound (1-6) is formed on an alignment film formed on a glass substrate, and the phase transition temperature is confirmed by texture observation with a polarizing microscope (BX-51, manufactured by Olympus) while heating. It was confirmed that when the film containing compound (1-6) was heated to 120°C and then cooled, the phase changed to nematic phase at 112°C, to smectic A phase at 110°C, and to smectic A phase at 94°C. Stratum B phase.

Compound (1-7) (compound represented by the following formula (1-7))

The compound (1-7) was synthesized with reference to the synthesis of the above-mentioned compound (1-6).

[Determination of phase transition temperature]

The phase transition temperature of compound (1-7) was confirmed in the same manner as the phase transition temperature measurement of compound (1-6). It was confirmed that when the temperature of compound (1-7) was raised to 140°C and then lowered, the phase changed to nematic phase at 133°C, to smectic A phase at 118°C, and to smectic B phase at 78°C .

Example 1 [Preparation of this composition etc.]

The following components were mixed and stirred at 80°C for 1 hour to obtain the present composition (composition for polarizing film formation).

D10 pigment described in Japanese Patent No. 3687130

Polymerization initiator:

[Determination of phase transition temperature]

In the same manner as in the case of the compound (1-6) and the compound (1-7), the phase transition temperature of the polymerizable liquid crystal compound contained in the present composition prepared as described above was determined. It is confirmed that when the temperature is raised to 140°C and then the temperature is lowered, the phase separation state does not form and the phase changes to nematic phase at 109°C, and the phase separation state does not form at 98°C and the phase changes to smectic A phase at 74°C. The phase separation state is not formed and the phase is transformed into smectic B phase.

[Manufacturing and evaluation of this polarizing film] 1. Formation of alignment film

Use a glass substrate as a transparent substrate.

A 2% by mass aqueous solution (composition for forming an alignment layer) of polyvinyl alcohol (polyvinyl alcohol 1000 completely saponified type, manufactured by Wako Pure Pharmaceutical Co., Ltd.) was coated on the glass substrate by a spin coating method, and dried After that, a film with a thickness of 100 nm was formed. Then, by performing rubbing treatment on the surface of the obtained film, an alignment layer is formed, and a polarizing film is produced. The friction treatment system uses a semi-automatic friction device (trade name: LQ-008, manufactured by Changyang Engineering Co., Ltd.), using cloth (trade name: YA-20-RW, manufactured by Yoshikawa Chemical Co., Ltd.) at a press-in amount of 0.15 mm , The speed is 500rpm, 16.7mm/s. By this rubbing treatment, a laminate 1 in which an alignment film is formed on a glass substrate is obtained.

2. Formation of polarizing film

The composition for forming a polarizing film was 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 1 minute, and then rapidly cooled to room temperature to form on the alignment film Coating film. In the coating film, the liquid crystal state of the polymerizable liquid crystal compound contained is smectic B phase. Then, using a UV irradiation device (SPOTCURESP-7, manufactured by Ushio Electric Co., Ltd.), ^{the coating film was irradiated with ultraviolet rays at an exposure amount of 2000 mJ/cm 2} (313 nm standard), thereby making the polymerizable liquid crystal contained in the coating film The compound is polymerized while maintaining the aforementioned liquid crystal state, and a polarizing film is produced from the coating film. The thickness of the polarizing film at this time was measured using a laser microscope (OLS3000 manufactured by Olympus Co., Ltd.), and the result was 1.6 μm.

3. X-ray diffraction measurement

The obtained polarizing film was subjected to X-ray diffraction measurement using an X-ray diffraction device X'Pert PRO MPD (manufactured by Spectris Co., Ltd.). Use Cu as a target to generate X-rays under the conditions of X-ray tube current 40mA and X-ray tube voltage 45kV. The generated X-rays are incident from the alignment direction through a fixed divergence slit 1/2°, and the scanning range 2θ=4.0 The measurement was carried out with 2θ=0.01671° step scan in the range of ~40.0°. As a result, a steep Bragg peak of FWHM (Full Width Half Maximum) = about 0.1718° was obtained near 2θ=20.24°. It is also known that even if it is incident from a direction parallel to the surface of the polarizing film and perpendicular to the alignment direction, the same result can be obtained. The order period (d) calculated from the position of the wave crest is about 4.4 Å, forming a structure reflecting the higher order stratigraphic facies.

4. Measurement of Dichroic Ratio (DR, Dichroic Ratio) = Determine the dichroic ratio in the following way

Using a spectrophotometer (UV-3150 manufactured by Shimadzu Corporation) with a polarizer attached to the device, the absorbance in the transmission axis direction at the maximum absorption wavelength (A ¹ ) And the absorbance in the direction of the absorption axis (A ² ). The folder is a net that cuts off 50% of the light on the reference side. Calculate the ratio (A ² /A ¹ ) from the measured absorbance in the direction of the transmission axis (A ¹ ) and absorbance (A ² ) in the direction of the absorption axis as the dichroic ratio. The higher the dichroic ratio, the better the characteristics as a polarizing film. Table 1 shows the measurement results of the maximum absorption wavelength of the absorbance (A ^{2) in the direction of the absorption axis and the dichroic ratio at this wavelength.}

5. Determination of haze value

In order to confirm the transparency of the polarizer, a haze meter (HZ-2, manufactured by Suga Test Instruments Co., Ltd.) was used to measure the haze value. The measurement results are shown in Table 1.

Examples 2 to 8, Reference Example 1, and Comparative Examples 1 to 2 were prepared in the same manner except that the type and content of the polymerizable non-liquid crystal compound were changed. In addition, in Comparative Example 3, the composition was prepared without adding polymerizable non-liquid crystal compounds. After coating and drying at 120°C, the composition was quickly moved on a hot plate at 70°C, followed by UV exposure. This produces a polarizing film. Table 1 shows the respective measurement results.

In Examples 9-15, the dichroic dye was changed to the following structural formula (2-3-1), and the type and content of the polymerizable non-liquid crystal compound were changed, except that the polarized light was produced in the same manner as in Example 1. membrane. Table 1 shows the respective measurement results.

Examples 1-15 did not form a phase-separated state and showed good horizontal alignment and high dichroism. The good horizontal alignment is due to the polymerizable liquid crystal compound showing a nematic liquid crystal phase, and the higher dichroism is due to the polymerizing liquid crystal compound showing a smectic liquid crystal phase.

[Industrial availability]

The polarizing film can be preferably used as a display device (display). Therefore, the present composition that can manufacture the present polarizing film has a high industrial value.

Claims (18)

A composition for forming a polarizing film, which contains a polymerizable liquid crystal compound, a polymerizable non-liquid crystal compound, a dichroic dye, a polymerization initiator and a solvent, the polymerizable non-liquid crystal compound is a monofunctional acrylate or a multifunctional acrylate, and The composition for forming a polarizing film satisfies the following requirements (A) and (B): (A) the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound both have a polymerizable group; (B) is obtained from the composition for forming a polarizing film The polymerizable liquid crystal compound contained in the coating film does not form a phase separation state, and shows a nematic liquid crystal phase and a higher order smectic phase. The composition for forming a polarizing film according to claim 1, wherein the polymerizable group of the polymerizable liquid crystal compound and the polymerizable group of the polymerizable non-liquid crystal compound are independently acryloxy groups (CH ₂ =CHCOO-) Or methacryloxy group (CH ₂ =C(CH ₃ )COO-). The composition for forming a polarizing film according to claim 1 or 2, wherein the polymerizable group possessed by the polymerizable liquid crystal compound is the same as the polymerizable group possessed by the polymerizable non-liquid crystal compound. The composition for forming a polarizing film according to claim 1 or 2, wherein the polymerizable liquid crystal compound has 1 to 2 polymerizable groups in the molecule, and the polymerizable non-liquid crystal compound has 2 to 6 polymerizable groups in the molecule. The composition for forming a polarizing film according to claim 1 or 2, wherein the content of the polymerizable non-liquid crystal compound is 3 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymerizable liquid crystal compound. A composition for forming a polarizing film, which contains a polymerizable liquid crystal compound, a polymerizable non-liquid crystal compound, a dichroic dye, a polymerization initiator, and a solvent, and the composition for forming a polarizing film satisfies the following (A) and (B) Prerequisites: (A) Both the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound have a polymerizable group, and the polymerizable group of the polymerizable liquid crystal compound and the polymerizable group of the polymerizable non-liquid crystal compound are independently acrylic acid Oxy group (CH ₂ =CHCOO-) or methacryloxy group (CH ₂ =C(CH ₃ )COO-); (B) the polymerizability contained in the coating film obtained from the composition for forming a polarizing film The liquid crystal compound does not form a phase-separated state, and exhibits a nematic liquid crystal phase and a higher order smectic phase. The composition for forming a polarizing film according to claim 6, wherein the polymerizable group possessed by the polymerizable liquid crystal compound is the same as the polymerizable group possessed by the polymerizable non-liquid crystal compound. The composition for forming a polarizing film according to claim 6 or 7, wherein the polymerizable liquid crystal compound has 1 to 2 polymerizable groups in the molecule, and the polymerizable non-liquid crystal compound has 2 to 6 polymerizable groups in the molecule. The composition for forming a polarizing film according to claim 6 or 7, wherein the content of the polymerizable non-liquid crystal compound is 3 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymerizable liquid crystal compound. A composition for forming a polarizing film, comprising a polymerizable liquid crystal compound, a polymerizable non-liquid crystal compound, a dichroic dye, a polymerization initiator, and a solvent, and the composition for forming a polarizing film satisfies the following (A) and (B) Prerequisites: (A) Both the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound have a polymerizable group, and the polymerizable group of the polymerizable liquid crystal compound is the same as the polymerizable group of the polymerizable non-liquid crystal compound; (B) Polymerizable liquid crystal contained in coating film obtained from composition for forming polarizing film The compound does not form a phase-separated state, and shows a nematic liquid crystal phase and a higher order smectic phase. The composition for forming a polarizing film according to claim 10, wherein the polymerizable liquid crystal compound has 1 to 2 polymerizable groups in the molecule, and the polymerizable non-liquid crystal compound has 2 to 6 polymerizable groups in the molecule. The composition for forming a polarizing film according to claim 10 or 11, wherein the content of the polymerizable non-liquid crystal compound is 3 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymerizable liquid crystal compound. A method for manufacturing a polarizing film, comprising the following steps (I), (II) and (III): (I) coating the polarizing film forming composition according to any one of claims 1 to 12 on a substrate The step of removing the solvent to form a coating film on or on the alignment film formed on the substrate; (II) Bring the polymerizable liquid crystal compound contained in the coating film formed in (I) into a higher order smectic state (III) The step of copolymerizing the polymerizable liquid crystal compound and the polymerizable non-liquid crystal compound in the coating film of the polymerizable liquid crystal compound formed in (II) in a higher order smectic state. The method for manufacturing a polarizing film according to claim 13, wherein the substrate is a transparent substrate subjected to alignment treatment. For example, the method of manufacturing a polarizing film of claim 13 or 14, wherein the step (II) includes the steps of step (I-1) and step (I-2), and the above step (I-1) is a heat treatment until (I) ) Until the polymerizable liquid crystal compound contained in the coating film formed in the step shows a nematic liquid crystal phase, the above step (I-2) is to make the polymerizable liquid crystal compound formed in the step (I-1) a nematic The coating film in the liquid crystal phase state is cooled until the polymerizable liquid crystal compound shows a higher order smectic phase. A polarizing film, which is manufactured by the manufacturing method of any one of claims 13 to 15 manufacture. Such as the polarizing film of claim 16, wherein the Bragg peak is shown in the diffraction measurement of X-rays. A display device comprising the polarizing film as claimed in claim 16 or 17.

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