KR102129835B1 - Compound and dichroic dye, and polarizing film - Google Patents

Abstract

[식 (1)에서, Y는 식 (Y1) 또는 식 (Y2)로 표시되는 기이다.

R¹은 식 (R¹-1)∼식 (R¹-3) 중 어느 것으로 표시되는 기이다.

R²는 식 (R²-1)∼식 (R²-6) 중 어느 것으로 표시되는 기이다.

An object of the present invention is to provide a novel compound capable of forming a polarizing film having a maximum absorption at a wavelength of 400 to 520 nm and having a high dichroic ratio, and a polarizing film containing the new compound.
Provided are a compound represented by Formula (1), a composition comprising the compound and a liquid crystal compound, and a polarizing film formed from the composition.

[In Formula (1), Y is a group represented by Formula (Y1) or Formula (Y2).

R ¹ is a group represented by any of formulas (R ¹ -1) to (R ¹ -3).

R ² is a group represented by any of formulas (R ² -1) to (R ² -6).

Description

Compound and dichroic dye, and polarizing film {COMPOUND AND DICHROIC DYE, AND POLARIZING FILM}

The present invention relates to a novel compound, a dichroic dye, and a polarizing film using the dichroic dye.

As the polarizer used in the liquid crystal display device, a film made of polyvinyl alcohol dyed with iodine is usually used. On the other hand, in recent liquid crystal display devices, the thinning thereof is strongly demanded, and accordingly, the thinner polarizer is also required. It is known to contain a dichroic dye as a polarizing film possessed by a thin polarizer.

For example, Patent Document 1 describes a polarizing film formed by depositing a specific polyazo-based dye material, but cannot be said to be an industrially advantageous method because a special device such as a vapor deposition device is required to form the polarizing film. On the other hand, Patent Document 2 describes a polarizing film formed of a composition comprising a polymerizable liquid crystal compound having a higher order Smectic Sx phase and a dichroic dye, but a dichroic dye having a maximum absorption at a wavelength of 400 to 520 nm, which is dichroic None of the composition containing the dye or the polarizing film formed from the composition is described. As a yellow-orange dichroic dye having a maximum absorption at a wavelength of 400 to 520 nm, Patent Document 3 discloses a biszo-based dye having a 1,4-naphthyl structure.

Patent Document 1: Japanese Patent No. 3687130 Patent Document 2: Japanese Patent No. 4719156 Patent Document 3: Japanese Patent No. 1454637

However, as a result of examination by the present inventors, when the dichroic dye (bisazo-based dye) described in Patent Document 3 is combined with a higher order smectic liquid crystal compound, it is dispersed between dense molecular chains formed of the higher order smectic liquid crystal compound. It became clear that in this case, only a polarizing film having a low dichroic ratio and poor polarization performance was obtained. The object of the present invention is a compound having a maximum absorption at a wavelength of 400 to 520 nm and capable of forming a polarizing film having a high dichroic ratio, a dichroic dye comprising the compound as an active ingredient, a dichroic dye and a polymerizable liquid crystal compound. It is to provide a composition and a polarizing film formed from the composition.

The present invention includes the following inventions.

[1] A compound characterized by being represented by formula (1).

[In Formula (1), Y is a group represented by Formula (Y1) or Formula (Y2).

(In the formula, L is an oxygen atom or -NR-, and R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.)

R ¹ is a group represented by formula (R ¹ -1), formula (R ¹ -2) or formula (R ¹ -3).

(In the formula, ma is an integer from 0 to 10, and when there are two ma in the same group, the two ma are the same or different from each other. * represents the number of bonds.)

R ² is the formula (R ² -1), the formula (R ² -2), the formula (R ² -3), the formula (R ² -4), the formula (R ² -5) or the formula (R ² -6) It is a group represented by.

(In the formula, mb is an integer from 0 to 10. * represents the number of bonds.)]

[2] A dichroic dye comprising the compound described in [1] as an active ingredient.

[3] A composition comprising the compound according to [1] and a polymerizable liquid crystal compound.

[4] The composition according to [3], wherein the polymerizable liquid crystal compound is a compound exhibiting a smectic liquid crystal phase.

[5] The composition according to [3] or [4], further comprising a solvent.

[6] The composition according to any of [3] to [5], further comprising a polymerization initiator.

[7] A polarizing film comprising the composition according to any one of [3] to [6].

[8] The maximum absorption wavelength (λmax1) of the polarizing film is

The polarizing film according to [7], characterized in that the wavelength is shifted longer than the maximum absorption wavelength (λmax2) of the dichroic dye.

[9] The polarizing film according to [7] or [8], wherein the difference between the maximum absorption wavelength (λmax1) of the polarizing film and the maximum absorption wavelength (λmax2) of the dichroic dye is 20 nm or more.

[10] The polarizing film according to any of [7] to [9], wherein a Bragg peak is obtained in X-ray diffraction measurement.

[11] A polarizer comprising the polarizing film according to any one of [7] to [10] and a transparent substrate.

[12] a process for preparing a laminate in which an alignment film is laminated on a transparent substrate;

A step of applying the composition described in any of [3] to [6] on the alignment film of the laminate to form a coating film,

And a step of polymerizing the polymerizable liquid crystal compound contained in the coating film.

[13] a step of forming a laminate by forming a photo-alignment film on a transparent substrate,

A step of applying the composition described in any of [3] to [6] on the photo-alignment film of the laminate to form a coating film,

And a step of polymerizing the polymerizable liquid crystal compound contained in the coating film.

[14] A liquid crystal display device comprising the polarizing film according to any one of [7] to [10].

[15] A circular polarizing plate comprising the polarizing film according to any one of [7] to [10], a quarter wave plate, and satisfying the following requirements (A1) and (A2).

(A1) the angle between the absorption axis of the polarizing film and the slow axis of the quarter wave plate should be approximately 45°;

(A2) The value of the front retardation of the quarter wave plate measured at light having a wavelength of 550 nm should be in the range of 100 to 150 nm.

[16] An organic EL display device comprising the circular polarizing plate according to [15] and an organic EL element.

According to the present invention, a compound capable of forming a polarizing film having a maximum absorption at a wavelength of 400 to 520 nm and having a high dichroic ratio, a dichroic dye comprising the compound as an active ingredient, a dichroic dye and a polymerizable liquid crystal compound It is possible to provide a polarizing film formed of a composition and a composition.

1 is a schematic view of a method for continuously manufacturing a polarizer (this polarizer) comprising the polarizing film of the present invention.
It is a schematic diagram which shows the relationship between the orientation direction D2 of a photo-alignment film, and the conveyance direction D1 of a film.
3 is a schematic view showing a cross-sectional configuration of a liquid crystal display device using the polarizing film of the present invention.
FIG. 4 is a schematic diagram showing the layer order of the polarizer used in the liquid crystal display of FIG. 3.
5 is a schematic view showing the layer order of the present polarizer used in the liquid crystal display of FIG. 3.
6 is a schematic view showing a cross-sectional configuration of an EL display device using the polarizing film of the present invention.
It is a schematic diagram which shows the sectional structure of the embodiment of this polarizer containing the polarizing film of this invention.
8 is a schematic view showing an example of a method for continuously manufacturing a circular polarizing plate (this circular polarizing plate) containing the polarizing film of the present invention.
Fig. 9 is a schematic diagram showing the layer order of the original polarizing plate used in the EL display device of Fig. 6;
10 is a schematic view showing a cross-sectional configuration of an EL display device using the polarizing film of the present invention.
11 is a schematic diagram showing the configuration of a projection type liquid crystal display device using the polarizing film of the present invention.

The present invention is a dichroic dye comprising the compound represented by the formula (1) (hereinafter, sometimes referred to as "compound (1)") and the compound (1) as an active ingredient (hereinafter, sometimes referred to as "dichroic dye" (1)”, a composition containing the dichroic dye and a polymerizable liquid crystal compound (hereinafter referred to as “a composition for forming a polarizing film” in some cases), and a polarizing film (hereinafter referred to as “a composition for forming a polarizing film”) , In some cases, referred to as "this polarizing film." This polarizing film is not only suitably used for a liquid crystal display device, but also makes it possible to manufacture a circular polarizing plate suitable for an organic EL display device (hereinafter referred to as "this circular polarizing plate" in some cases). First, compound (1) will be described.

<Compound (1)>

Compound (1) is represented by the formula (1).

Suitable embodiments of the compound (1) will be described taking each group of the formula (1) as an example.

The geometric isomer of the azobenzene moiety of formula (1) is preferably trans.

Y in Formula (1) is a group represented by Formula (Y1) or Formula (Y2) described above, and is preferably a group represented by Formula (Y1). In formulas (Y1) and (Y2), the straight lines at both ends represent the number of bonds, the number of bonds on the left side is bonded to a phenylene group having an azo group, and the number of bonds on the right side is bonded to a phenylene group having R ² . have. L is an oxygen atom or -NR-, and R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group and t-butyl group. Among them, L is preferably an oxygen atom or -NH-, and more preferably an oxygen atom.

R ¹ is a group represented by the above formula (R ¹ -1), formula (R ¹ -2) or formula (R ¹ -3), preferably formula (R ¹ -2) and formula (R ^1- It is a group represented by 3). Two ma in the group represented by the formula (R ¹ -2) may be the same or different, but preferably the same. More preferably, ma is an integer from 0 to 5.

R ² is the above formula (R ² -1), formula (R ² -2), formula (R ² -3), formula (R ² -4), formula (R ² -5) or formula (R ^2- It is a group represented by 6), and is more preferably a group represented by formula (R ² -2), formula (R ² -5) or formula (R ² -6), represented by formula (R ² -6) If it is a group, it is more preferable. If R ² is a group represented by formula (R ² -1), formula (R ² -2), formula (R ² -3), formula (R ² -5) or formula (R ² -6), The included mb is preferably an integer from 0 to 5, and more preferably an integer from 0 to 3.

Preferred compounds (1) include compounds represented by the following formulas (1-1) to (1-8).

Especially, the compound represented by Formula (1-1), Formula (1-2), Formula (1-3), Formula (1-5), Formula (1-7), and Formula (1-8) is preferable. , Compounds represented by formula (1-1), formula (1-2), formula (1-3) and formula (1-7) are particularly preferred.

Here, a method for producing compound (1) will be described. Compound (1) can be produced by, for example, a reaction represented by the following scheme from a compound represented by formula (1X) [compound (1X)] and a compound represented by formula (1Y) [compound (1Y)].

In the above scheme, R ¹ , R ² and Y have the same meaning as above, and Re ¹ and Re ² are groups that react with each other to be a group represented by Y. As the combination of Re ¹ and Re ² , for example, a combination of a carboxy group and a hydroxyl group, a combination of a carboxy group and an amino group (these amino groups may be substituted with R), a combination of a carbonyl halide group and a hydroxyl group, a carbonyl halide group and an amino group (these amino groups) Is a combination of R may be substituted), a combination of a carbonyloxyalkyl group and a hydroxyl group, a combination of a carbonyloxyalkyl group and an amino group (these amino groups may be substituted with R), and the like. In addition, although the compound (1X) having R ¹ and the compound (1Y) having R ² are described herein, a compound protected by R ¹ with a suitable protecting group or a compound protected with R ² by a suitable protecting group reacts with each other, and Thereafter, compound (1) can also be produced by performing an appropriate deprotection reaction.

Reaction conditions when reacting compound (1X) and compound (1Y) can be appropriately selected according to the type of compound (1X) and compound (1Y) to be used, and optimally known conditions can be selected.

For example, the reaction conditions when Re ¹ is a carboxy group, Re ² is a hydroxyl group, and Y is -C(=O)-O- include, for example, conditions for condensation in the presence of an esterified condensing agent in a solvent. Examples of the solvent include a solvent soluble in both compound (1X) such as chloroform and compound (1Y). Diisopropyl carbodiimide (IPC) etc. are mentioned as an esterified condensing agent. Here, it is preferable to use a base such as dimethylaminopyridine (DMAP) in combination. The reaction temperature is selected depending on the type of the compound (1X) and the compound (1Y). For example, a range of -15 to 70°C is mentioned, and preferably 0 to 40°C. The reaction time is, for example, in the range of 15 minutes to 48 hours.

The reaction time is appropriately sampled during the reaction, and the degree of loss of compound (1X) and compound (1Y) or the degree of production of compound (1) can be determined by known analytical means such as liquid chromatography and gas chromatography. It can also be determined by confirmation.

Compound (1) can be extracted from the reaction mixture after the reaction by known methods such as recrystallization, reprecipitation, extraction and various chromatography, or by combining these operations.

Compound (1) is useful as a dichroic dye used in polarizing films. Such a dichroic dye may contain a compound other than compound (1) as long as it does not significantly impair the one having a maximum absorption in the range of 400 to 520 nm, but is preferably a dichroic dye comprising only compound (1). The dichroic dye (1) is more preferable if its absorption maximum is 430 to 520 nm, particularly preferably 440 to 510 nm. On the other hand, as long as the dichroic dye (1) exhibits an absorption maximum in the above range, the dichroic dye (1) may contain a plurality of types of compounds (1).

<Polarizing film forming composition>

Next, the composition for forming a polarizing film of the present invention will be described. The composition for forming a polarizing film contains a polymerizable liquid crystal compound.

The content of the dichroic dye (1) in the composition for forming a polarizing film is preferably 50 parts by mass or less, more preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 0.1 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. The range of 5 parts by mass or more is more preferable. If it is in the said range, the solubility of the dichroic dye 1 in a solvent is sufficient, and it is easy to obtain this polarizing film which does not generate defects. Moreover, if the content of the dichroic dye (1) is within the above range, it is preferable that the orientation of the polymerizable liquid crystal compound is hard to be disturbed in the formation of the polarizing film.

Components other than the dichroic dye (1) in the composition for forming a polarizing film of the present invention will be described.

<Polymerizable liquid crystal compound>

The composition for forming a polarizing film containing the dichroic dye (1) and a polymerizable liquid crystal compound is a polarizing film viewed by polymerizing the polymerizable liquid crystal compound in an aligned state. The polymerizable liquid crystal compound is a liquid crystal compound having a polymerizable group in a molecule, and this polymerizable group is particularly preferable as long as it is a radical polymerizable group. The radical polymerizable group means a group involved in the radical polymerization reaction.

The polymerizable liquid crystal compound contained in the composition for forming a polarizing film of the present invention may exhibit a nematic liquid crystal phase, a smectic liquid crystal phase, or both a nematic liquid crystal phase and a smectic liquid crystal phase. , It is preferable if it is a polymerizable smectic liquid crystal compound showing at least a smectic liquid crystal phase. A composition for forming a polarizing film containing a polymerizable smectic liquid crystal compound is preferable in that a polarizing film having better polarization performance can be obtained, and the dichroic dye (1) is formed of a polymerizable smectic liquid crystal compound. Even in the state dispersed between the molecular chains, since the present polarizing film having a very high dichroic ratio can be obtained, the effect of the dichroic dye 1 can be further enjoyed.

As the smectic liquid crystal phase represented by the polymerizable smectic liquid crystal compound, a higher order smectic liquid crystal phase is preferable. The higher order smectic liquid crystal phases referred to herein are smectic B phase, smectic D phase, smectic E phase, smectic F phase, smectic G phase, smectic H phase, smectic I phase, smectic J phase, sm Smectic K phase and Smectic L phase, among them, Smectic B phase, Smectic F phase and Smectic I phase are more preferable. If the smectic liquid crystal phase represented by the polymerizable liquid crystal compound is these higher order smectic liquid crystal phases, the present polarizing film with higher alignment order can be produced. In addition, in this X-ray diffraction measurement, this polarizing film produced from a high order smectic liquid crystal phase having a high degree of alignment is obtained with a Bragg peak derived from a high order structure such as a hexatic phase or a crystal phase. The Bragg peak is a peak derived from a molecularly oriented surface periodic structure, and according to the composition for forming a polarizing film of the present invention, a main polarizing film having a periodic interval of 3.0 to 5.0 kPa can be obtained.

Whether the polymerizable liquid crystal compound contained in the composition for forming a polarizing film exhibits nematic liquid crystal or smectic liquid crystal can be confirmed, for example, as follows. After preparing a suitable substrate and applying a composition for forming a polarizing film to the substrate to form a coating film, the solvent contained in the coating film is removed by subjecting the polymerizable liquid crystal compound to heat treatment or reduced pressure treatment under conditions that do not polymerize. Subsequently, the coating film formed on the substrate is heated to an isotropic temperature, and the liquid crystal phase expressed by cooling slowly is inspected by texture observation with a polarization microscope, X-ray diffraction measurement, or differential scanning calorimetry. In this inspection, for example, a polymerizable liquid crystal compound that exhibits a nematic liquid crystal phase by cooling and a smectic liquid crystal phase by further cooling is particularly preferable. In the nematic liquid crystal phase and the smectic liquid crystal phase, the phase separation of the polymerizable liquid crystal compound and the dichroic dye 1 can be confirmed by, for example, surface observation using various microscopes or scattering degree measurement using a haze meter.

Hereinafter, the specific example of what is preferable as a polymerizable liquid crystal compound used for the composition for polarizing film formation is given.

As a preferable polymerizable liquid crystal composition, a compound represented by Formula (2) (hereinafter, sometimes referred to as "compound (2)") is mentioned.

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

In the formula (2), X ¹ , X ² and X ³ each independently represent a 1,4-phenylene group which may have a substituent or a cyclohexane-1,4-diyl group which may have a substituent. However, at least one of X ¹ , X ² and X ³ is a 1,4-phenylene group which may have a substituent. -CH ₂ -constituting a cyclohexane-1,4-diyl group which may have a substituent may be substituted with -O-, -S- or -NR-. R is a C1-C6 alkyl group or a phenyl group.

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

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

In compound (2), 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.

It is preferable that the 1,4-phenylene group which may have a substituent is unsubstituted. The cyclohexane-1,4-diyl group which may have a substituent is preferably a trans-cyclohexane-1,4-diyl group which may have a substituent, and a trans-cyclohexane-1,4- which may have a substituent. The diyl group is more preferably unsubstituted.

Examples of the substituent optionally having a 1,4-phenylene group which may have a substituent or a cyclohexane-1,4-diyl group which may have a substituent include alkyl groups having 1 to 4 carbon atoms such as methyl group, ethyl group, and butyl group; Cyano group; And halogen atoms.

Y ¹ of compound (2) 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, and preferably a polymerizable group. U ¹ and U ² are preferably a polymerizable group together, and more preferably a photopolymerizable group together. Here, a photopolymerizable group means a group that can be involved in a polymerization reaction by an active radical or an acid generated from a photopolymerization initiator described later. The polymerizable liquid crystal compound having a photopolymerizable group is advantageous in that it can polymerize under lower temperature conditions.

In the compound (2), the polymerizable groups of U ¹ and U ² may be different from each other, but are preferably the same kind of group. Examples of the polymerizable group include vinyl group, vinyloxy group, 1-chlorovinyl group, isopropenyl group, 4-vinylphenyl group, acryloyloxy group, methacryloyloxy group, oxiranyl group, and oxetanyl group. Especially, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxiranyl group, and an oxetanyl group are preferable, and an acryloyloxy group is more preferable.

Examples of the alkanediyl group having 1 to 20 carbon atoms which may have the substituents represented by V ¹ and V ² include a methylene group, ethylene group, propane-1,3-diyl group, butane-1 ,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group , A decane-1,10-diyl group, a tetradecane-1,14-diyl group, and an aicosan-1,20-diyl group. V ¹ and V ² are preferably an alkanediyl group having ² to 12 carbon atoms, and more preferably an alkanediyl group having 6 to 12 carbon atoms.

Examples of the substituent optionally having an 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, and more preferably unsubstituted and straight-chain.

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

Examples of the compound (2) include compounds represented by formulas (2-1) to (2-43). When the specific example of such compound (2) has a cyclohexane-1,4-diyl group, it is preferable that such cyclohexane-1,4-diyl group is a transchain.

The polymerizable liquid crystal compound may be used alone or in combination of two or more in a composition for forming a polarizing film. Moreover, when mixing 2 or more types, it is preferable if at least 1 type is a compound (2). The mixing ratio when two types of polymerizable liquid crystal compounds are mixed is usually 1:99 to 50:50, preferably 5:95 to 50:50, and more preferably 10:90 to 50:50.

Among the illustrated compound (2), formula (2-5), formula (2-6), formula (2-7), formula (2-8), formula (2-9), formula (2-10), formula (2-11), Expression (2-12), Expression (2-13), Expression (2-14), Expression (2-15), Expression (2-22), Expression (2-24), Expression ( 2-25), the compound represented by formula (2-26), formula (2-27), formula (2-28), and formula (2-29) is preferable. These compounds can be easily polymerized by interacting with other polymerizable liquid crystal compounds under temperature conditions below the crystalline phase transition temperature, that is, while maintaining a high-order smectic liquid crystal state sufficiently. Specifically, these compounds can be polymerized under a temperature condition of 70°C or lower, preferably 60°C or lower, while sufficiently maintaining a high-order smectic liquid crystal state.

The content ratio of the polymerizable liquid crystal compound in the composition for forming a polarizing film is preferably 50 to 99.9% by mass, more preferably 80 to 99.9% by mass with respect to the solid content of the composition for forming a polarizing film. When the content ratio of the polymerizable liquid crystal compound is within the above range, the orientation of the polymerizable liquid crystal compound tends to increase, which is preferable. Here, solid content means the total amount of the components except for volatile components, such as a solvent, in the composition for polarizing film formation.

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

<solvent>

It is preferable that the composition for polarizing film formation in this invention contains a solvent. As the solvent, a solvent capable of completely dissolving the polymerizable liquid crystal compound and the dichroic dye (1) is preferable. Moreover, it is preferable that it is a solvent inert to the polymerization reaction of the polymerizable liquid crystal compound contained in the composition for forming a polarizing film.

Examples of the solvent include alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, and propylene glycol monomethyl ether; Ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone or propylene glycol methyl ether acetate and ethyl lactate; Ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone and methyl isobutyl ketone; Aliphatic hydrocarbon solvents such as pentane, hexane and heptane; Aromatic hydrocarbon solvents such as toluene and xylene; Nitrile solvents such as acetonitrile; Ether solvents such as tetrahydrofuran and dimethoxyethane; And chlorine-containing solvents such as chloroform and chlorobenzene. These solvents may be used alone or in combination of a plurality.

The content ratio of the solvent is preferably 50 to 98% by mass relative to the total amount of the composition for forming a polarizing film. In other words, 2-50 mass% of solid content in the composition for polarizing film formation is preferable. When the solid content is 2% by mass or more, it is preferred because it tends to easily obtain a thin, thin polarizing film. Moreover, when the said solid content is 50 mass% or less, since the viscosity of the composition for polarizing film formation becomes low, since the thickness of this polarizing film becomes substantially uniform, there is a tendency for stains to hardly occur in this polarizing film, which is preferable. In addition, such a solid content can be determined in consideration of the thickness of the polarizing film.

<Preparation of polymerization reaction>

It is preferable if the composition for polarizing film formation in this invention contains a polymerization initiator. The polymerization initiator is a compound capable of initiating the polymerization reaction of the polymerizable liquid crystal compound. As the polymerization initiator, a photopolymerization initiator is preferable in that the polymerization reaction can be started under low temperature conditions. Specifically, a compound that generates active radicals or acids by the action of light is used as a photopolymerization initiator. Among photoinitiators, it is more preferable to generate active radicals by the action of light.

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

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

Examples of benzophenone compounds include benzophenone, o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenylsulfide, 3,3',4,4'-tetra(tert-butylperoxycar Carbonyl) benzophenone and 2,4,6-trimethylbenzophenone.

Examples of the alkylphenone compound include diethoxyacetophenone, 2-methyl-2-morpholino-1-(4-methylthiophenyl)propan-1-one, and 2-benzyl-2-dimethylamino-1-(4-morph Polynophenyl)butan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1,2-diphenyl-2,2-dimethoxyethan-1-one, 2-hydroxy Hydroxy-2-methyl-1-[4-(2-hydroxyethoxy)phenyl]propan-1-one, 1-hydroxycyclohexylphenylketone and 2-hydroxy-2-methyl-1-[4- (1-methylvinyl)phenyl] propan-1-one oligomer and the like.

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

As the triazine compound, for example, 2,4-bis(trichloromethyl)-6-(4-methoxyphenyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(4 -Methoxynaphthyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(4-methoxystyryl)-1,3,5-triazine, 2,4 -Bis(trichloromethyl)-6-[2-(5-methylfuran-2-yl)ethenyl]-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[ 2-(furan-2-yl)ethenyl]-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(4-diethylamino-2-methylphenyl) Tenyl]-1,3,5-triazine and 2,4-bis(trichloromethyl)-6-[2-(3,4-dimethoxyphenyl)ethenyl]-1,3,5-triazine, etc. Can be mentioned.

A polymerization initiator can also use what is marketed. As commercially available polymerization initiators, "Irgacure 907", "Irgacure 184", "Irgacure 651", "Irgacure 819", "Irgacure 250", "Irgacure 369" ( Chiba Japan Co., Ltd.); "Seikool BZ", "Seikool Z", "Seikool BEE" (Seiko Chemical Co., Ltd.); "Kayacure BP100" (Nippon Kayaku Co., Ltd.); "Kayacure UVI-6992" (manufactured by Dow Corporation); "Adeka Optoma SP-152", "Adeka Optoma SP-170" (ADEKA); "TAZ-A", "TAZ-PP" (Nihon Siberheg Screw); And "TAZ-104" (Sanwa Chemical Co., Ltd.).

When the composition for forming a polarizing film contains a polymerization initiator, the content can be appropriately adjusted depending on the type and amount of the polymerizable liquid crystal compound contained in the composition for forming a polarizing film, and the content of the polymerizable liquid crystal compound is usually 100 mass The content of the polymerization initiator relative to parts is 0.1 to 30 parts by mass, preferably 0.5 to 10 parts by mass, and more preferably 0.5 to 8 parts by mass. If the content of the polymerization initiator is within the above range, it is preferable because the polymerization can be performed without disturbing the orientation of the polymerizable liquid crystal compound.

When the composition for forming a polarizing film contains a photopolymerization initiator, the composition for forming a polarizing film may contain a photosensitizer. Examples of the photosensitizer include xanthone compounds such as xanthone and thioxanthone (eg, 2,4-diethylthioxanthone, 2-isopropylthioxanthone); Anthracene compounds such as anthracene and an alkoxy group-containing anthracene (for example, dibutoxyanthracene); Phenothiazine and rubrene; and the like.

When the composition for forming a polarizing film contains a photopolymerization initiator and a photosensitizer, the polymerization reaction of the polymerizable liquid crystal compound contained in the composition for forming a polarizing film is further promoted.

The content of the photosensitizer can be appropriately adjusted depending on the type and amount of the photopolymerization initiator and the polymerizable liquid crystal compound used in combination, and is usually 0.1 to 30 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound, preferably Is 0.5 to 10 parts by mass, and more preferably 0.5 to 8 parts by mass.

The composition for forming a polarizing film may contain a polymerization inhibitor to stably advance the polymerization reaction of the polymerizable liquid crystal compound. The degree of progress of the polymerization reaction of the polymerizable liquid crystal compound can be controlled by the polymerization inhibitor.

Examples of the polymerization inhibitor include radicals such as hydroquinone, alkoxy group-containing hydroquinone, alkoxy group-containing catechol (for example, butyl catechol, etc.), pyrogallol, 2,2,6,6-tetramethyl-1-piperidinyloxy radical. Supplements; Thiophenols; and β-naphthylamines and β-naphthols.

When the composition for forming a polarizing film contains a polymerization inhibitor, the content is appropriately adjusted depending on the type and amount of the polymerizable liquid crystal compound used and the content of the photosensitizer, and the content of the polymerizable liquid crystal compound is usually 100 parts by mass It is 0.1-30 mass parts with respect to this, Preferably it is 0.5-10 mass parts, More preferably, it is 0.5-8 mass parts. When the content of the polymerization inhibitor is within the above range, it is preferable because the orientation of the polymerizable liquid crystal compound contained in the composition for forming a polarizing film can be polymerized without disturbing the orientation.

<Leveling agent>

It is preferable that the composition for forming a polarizing film contains a leveling agent. The leveling agent has a function of adjusting the fluidity of the composition for forming a polarizing film to make the coating film obtained by applying the composition for forming a polarizing film more flat, and a surfactant and the like. Preferred leveling agents include leveling agents based on a polyacrylate compound, leveling agents based on a fluorine atom-containing compound, and the like.

Leveling agents based on polyacrylate compounds include "BYK-350", "BYK-352", "BYK-353", "BYK-354", "BYK-355", "BYK-358N", and "BYK- 361N", "BYK-380", "BYK-381" and "BYK-392" (BYK Chemie).

Examples of leveling agents based on fluorine atom-containing compounds are "megapark R-08", copper "R-30", copper "R-90", copper "F-410", copper "F-411", and copper "F" -443", East "F-445", East "F-470", East "F-471", East "F-477", East "F-479", East "F-482" and East "F- 483" [DIC Corporation]; "Suplon S-381", copper "S-382", copper "S-383", copper "S-393", copper "SC-101", copper "SC-105", "KH-40" and " SA-100" [AGC Chemical Co., Ltd.]; "E1830", "E5844" (Daikin Fine Chemical Genkyusho); "F-top EF301", copper "EF303", copper "EF351", copper "EF352" (Mitsubishima terri alden Shigasei Co., Ltd.) etc. are mentioned.

When the composition for forming a polarizing film contains a leveling agent, the content is usually 0.3 parts by mass or more and 5 parts by mass or less, preferably 0.5 parts by mass or more and 3 parts by mass or less, based on 100 parts by mass of the content of the polymerizable liquid crystal compound. . When the content of the leveling agent is within the above-mentioned range, it is easy to align the polymerizable liquid crystal compound horizontally, and it is preferable because the polarizing film obtained tends to be smoother. When the content of the leveling agent in the polymerizable liquid crystal compound exceeds the above-mentioned range, the resulting polarizing film tends to be easily stained. Meanwhile, the polarizing film forming composition may contain two or more kinds of leveling agents.

<Method of forming the polarizing film>

Next, a method of forming the present polarizing film with the composition for forming a polarizing film will be described. In such a method, the present polarizing film is formed by applying the composition for forming a polarizing film to a substrate, preferably a transparent substrate. Hereinafter, the transparent substrate will be described.

<Transparent description>

A transparent substrate is a substrate having transparency sufficient to transmit light, particularly visible light. The transparency refers to a property in which transmittance to light rays over a wavelength of 380 to 780 nm is 80% or more. Specifically, a glass base material, a plastic base material, etc. are mentioned as a transparent base material. Examples of the plastic constituting the plastic substrate include polyolefins such as polyethylene, polypropylene, and norbornene polymers; Cyclic olefin resins; Polyvinyl alcohol; Polyethylene terephthalate; Polymethacrylic acid esters; Polyacrylic acid esters; Cellulose esters such as triacetyl cellulose, diacetyl cellulose and cellulose acetate propionate; Polyethylene naphthalate; Polycarbonate; Polysulfone; Polyethersulfone; Polyether ketone; And plastics such as polyphenylene sulfide and polyphenylene oxide. Among them, cellulose esters, cyclic olefin resins, polyethylene terephthalate or polymethacrylic acid esters are particularly preferred because they are readily available on the market or have excellent transparency. In manufacturing the present polarizing film using such a transparent substrate, a support substrate or the like is adhered to the transparent substrate in that it can be easily handled without causing damage such as tearing when transporting or storing the transparent substrate. You may put it. Moreover, although it mentions later, when manufacturing a circular polarizing plate with this polarizing film, there may be a case where a phase difference property is provided to a plastic base material. In this case, the retardation property may be given to the plastic substrate by stretching treatment or the like.

When giving a retardation property to a plastic base material, a plastic base material which consists of a cellulose ester or a cyclic olefin resin is preferable at the point that it is easy to control the retardation value.

In the cellulose ester, at least a part of hydroxyl groups contained in cellulose is acetic acid esterified. The cellulose ester film made of such a cellulose ester can be easily obtained in the market. As a commercially available triacetyl cellulose film, for example, "Fuji Tak Film" (Fuji Shashin Film Co., Ltd.); "KC8UX2M", "KC8UY" and "KC4UY" (Konica Minolta Opt.). Such a commercially available triacetylcellulose film can be used as a transparent base material as it is or after providing retardation properties as necessary. In addition, it can be used as a transparent substrate after surface treatment such as anti-glare treatment, hard coat treatment, antistatic treatment or antireflection treatment is performed on the surface of the prepared transparent substrate.

In order to provide retardation property to a plastic substrate, it is by a method such as stretching the plastic substrate as described above. Any plastic base material made of a thermoplastic resin can be stretched, but a plastic base material made of a cyclic olefin resin is more preferable because it is easy to control the retardation property. The cyclic olefin-based resin is composed of, for example, a polymer or copolymer of a cyclic olefin such as norbornene or polycyclic norbornene-based monomer, and the cyclic olefin-based resin may partially include a ring-opening part. Moreover, you may hydrogenated the cyclic olefin resin containing a ring-opening part. Further, the cyclic olefin-based resin may be a copolymer of, for example, a cyclic olefin with a chain olefin or a vinylated aromatic compound (styrene, etc.), in that it does not significantly impair transparency or significantly increase hygroscopicity. In addition, a polar group may be introduced into the cyclic olefin-based resin.

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

Cyclic olefin resins are readily available on the market. As a commercially available cyclic olefin resin, "Topas" [Ticona (Germany)]; "Aton" [JSR Corporation]; "ZEONOR" and "ZEONEX" (Nippon Xeon Corporation); And "Apel" (manufactured by Mitsui Chemical Co., Ltd.). Such a cyclic olefin-based resin can be formed into a film (cyclic olefin-based resin film) by forming a film by a known film forming means such as a solvent casting method or a melt extrusion method. Moreover, the cyclic olefin resin film already marketed in the form of a film can also be used. As such a commercially available cyclic olefin resin film, "Essina" and "SCA40" (Sekisui Chemical Co., Ltd.); "Zeono Film" [Optes Co., Ltd.]; "Aton Film" [JSR Co., Ltd.] etc. are mentioned.

Next, a method of imparting retardation property to the plastic substrate will be described. The plastic substrate can impart retardation properties by a known stretching method. For example, a roll (winding body) in which a plastic base material is wound on a roll is prepared, and the plastic base material is continuously released from the winding body, and the released plastic base material is conveyed to a heating furnace. The set temperature of the heating furnace is in the range of the glass transition temperature of the plastic substrate (°C) to [glass transition temperature +100] (°C), preferably near the glass transition temperature (°C) to [glass transition temperature +50] (°C) ). In this heating furnace, when stretching in the traveling direction of the plastic substrate or in a direction orthogonal to the traveling direction, the conveying direction or tension is adjusted to incline at an arbitrary angle to perform a uniaxial or biaxial thermal stretching treatment. The draw ratio is usually in the range of about 1.1 to 6 times, and preferably in the range of about 1.1 to 3.5 times. Moreover, as a method of extending in an oblique direction, if the orientation axis can be continuously inclined at a desired angle, it is not particularly limited, and a known stretching method can be adopted. As such a stretching method, the method described in Unexamined-Japanese-Patent No. 50-83482 or Unexamined-Japanese-Patent No. 2-113920 is mentioned, for example.

The thickness of the transparent base material is preferably thin in terms of being able to secure sufficient transparency and sufficient weight for practical handling, but if it is too thin, the strength tends to decrease and workability tends to be poor. The suitable thickness of the glass substrate is, for example, about 100 to 3000 μm, and preferably about 100 to 1000 μm. A suitable thickness of the plastic substrate is, for example, about 5 to 300 µm, and preferably about 20 to 200 µm. When this polarizing film is used as a circular polarizing plate to be described later, the thickness of the transparent substrate is particularly preferably about 20 to 100 µm when used as a circular polarizing plate for mobile devices. On the other hand, in the case of providing retardation to the film by stretching, the thickness after stretching is determined by the thickness before stretching or the stretching ratio.

<Orientation film>

It is preferable that an alignment film is formed in the base material used for manufacture of this polarizing film. In that case, the composition for forming a polarizing film is applied on the alignment film. For this reason, it is preferable that the said alignment film has solvent tolerance to the extent that it does not melt|dissolve by application|coating of the composition for polarizing film formation, etc. Moreover, it is preferable to have heat resistance in the heat treatment for removal of a solvent and orientation of a liquid crystal. An alignment polymer can be used for formation of such an alignment film.

Examples of the oriented polymer include polyamide or gelatin having an amide bond in a molecule, polyimide having an imide bond in a molecule, and polyamic acid, a hydrolyzate thereof, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, polyoxa And polymers such as sol, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid or polyacrylic acid esters. Among these, polyvinyl alcohol is preferable. These oriented polymers forming the alignment film may be used alone or in combination of two or more.

The alignment polymer can be formed on the substrate by coating on the substrate as an alignment polymer composition (solution containing an alignment polymer) dissolved in a solvent. Examples of the solvent include water; Alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, methyl cellosolve, butyl cellosolve and propylene glycol monomethyl ether; Ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate and ethyl lactate; Ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, methyl amyl ketone and methyl isobutyl ketone; Aliphatic hydrocarbon solvents such as pentane, hexane and heptane; Aromatic hydrocarbon solvents such as toluene and xylene, nitrile solvents such as acetonitrile; Ether solvents such as tetrahydrofuran and dimethoxyethane; And chlorine-substituted hydrocarbon solvents such as chloroform and chlorobenzene. These organic solvents may be used alone or in combination of a plurality of species.

Further, a commercially available alignment film material may be used as it is as an alignment polymer composition for forming an alignment film. Commercially available alignment film materials include San-Eva (registered trademark, manufactured by Nissan Chemical Industries, Ltd.) and Optoma (registered trademark, manufactured by JSR Corporation).

As a method of forming an alignment film on the substrate, for example, a method of annealing by coating the substrate with the alignment polymer composition or a commercially available alignment film material or the like can be given. The thickness of the alignment film thus obtained is usually in the range of 10 to 10000 nm, and preferably in the range of 10 to 1000 nm.

It is preferable to perform rubbing (rubbing method) as necessary in order to impart an orientation regulating force to the alignment film. The polymerizable liquid crystal compound can be oriented in a desired direction by applying an alignment regulating force.

As a method of imparting an orientation regulating force by the rubbing method, for example, a rubbing cloth is rolled up, a rotating rubbing roll is prepared, and a laminate having a coating film for forming an alignment film formed on a substrate is placed on a stage, and toward a rotating rubbing roll. By conveying, the method of contacting the said coating film for orientation film formation and a rotating rubbing roll is mentioned.

Further, a so-called photo-alignment film can also be used. With the photo-alignment film, a composition comprising a polymer or monomer having a photoreactive group and a solvent (hereinafter referred to as “a composition for forming a photo-alignment layer” in some cases) is applied to a substrate to irradiate polarized light (preferably polarized UV). By doing so, it refers to an alignment film to which an orientation regulating force is applied. The photoreactive group refers to a group that generates liquid crystal alignment ability by irradiating light (light irradiation). Specifically, it causes the photoreaction which is the origin of the liquid crystal alignment ability, such as an alignment organic or isomerization reaction, a dimerization reaction, a photocrosslinking reaction, or a photolysis reaction of molecules generated by irradiation of light. Among these photoreactive groups, it is preferable to cause a dimerization reaction or a photocrosslinking reaction because it has excellent orientation and maintains a smectic liquid crystal state during polarizing film formation. As a photoreactive group capable of causing the above reaction, an unsaturated bond, particularly a double bond, is preferable, and a carbon-carbon double bond (C=C bond), a carbon-nitrogen double bond (C=N bond), and nitrogen-nitrogen Particularly preferred is a group having at least one selected from the group consisting of a double bond (N=N bond) and a carbon-oxygen double bond (C=O bond).

Examples of the photoreactive group having a C=C bond include a vinyl group, a polyene group, a steelbene group, a steelbazole group, a steelbazolium group, a chalcone group, and a cinnamoyl group. Examples of the photoreactive group having a C=N bond include groups having structures such as aromatic sheep base and aromatic hydrazone. Examples of the photoreactive group having an N=N bond include an azobenzene group, an azonaphthalene group, an aromatic heterocyclic azo group, a bis azo group, and a formazan group, and those having azoxybenzene as a basic structure. Examples of the photoreactive group having a C=O bond include a benzophenone group, a coumarin group, an anthraquinone group, and a maleimide group. These groups may have substituents such as alkyl groups, alkoxy groups, aryl groups, allyloxy groups, cyano groups, alkoxycarbonyl groups, hydroxyl groups, sulfonic acid groups and halogenated alkyl groups.

Among them, a photoreactive group capable of inducing a photodimerization reaction is preferred, and since a cinnamoyl group and a chalcone group have a relatively small amount of polarization required for photo-alignment, and it is easy to obtain a photo-alignment film excellent in thermal stability or stability over time. desirable. More specifically, it is particularly preferable that the polymer having a photoreactive group has a cinnamoyl group in which the terminal end of the polymer side chain has a cinnamic acid structure.

As a solvent of the composition for forming a photo-alignment layer, it is preferable to dissolve a polymer and a monomer having a photoreactive group, and examples of the solvent include a solvent used in the above-mentioned oriented polymer composition.

The concentration of the polymer or monomer having a photoreactive group with respect to the composition for forming a photo-alignment layer can be appropriately adjusted according to the type of the polymer or monomer having the photoreactive group or the thickness of the photo-alignment film to be produced. It is preferable to use 0.2 mass%, and the range of 0.3 to 10 mass% is particularly preferable. Further, the composition for forming the alignment layer may include a polymer material such as polyvinyl alcohol or polyimide or a photosensitizer in a range in which the properties of the photo-alignment film are not significantly impaired.

As a method of applying the oriented polymer composition or a composition for forming a photo-alignment layer to a substrate, coating methods such as spin coating, extrusion, gravure coating, die coating, bar coating and applicator methods, flexo methods, etc. A known method such as a printing method is employed. On the other hand, when the production of the polarizing film is performed by a continuous manufacturing method of a RolltoRoll type described later, a printing method such as a gravure coating method, a die coating method, or a flexo method is usually employed.

On the other hand, if masking is performed during rubbing or polarization irradiation, a plurality of regions (patterns) with different orientation directions may be formed.

<Method of manufacturing this polarizing film>

A composition for forming a polarizing film is coated on the substrate or the alignment film formed on the substrate to obtain a coating film. As a method of coating, for example, the same method as exemplified as a method of applying an alignment polymer composition or a composition for forming a photo-alignment layer to a substrate can be mentioned.

Subsequently, a dry film is formed by drying and removing the solvent under the condition that the polymerizable liquid crystal compound contained in the coating film is not polymerized. Examples of the drying method include a natural drying method, a ventilation drying method, a heating drying method and a vacuum drying method.

Subsequently, as a preferred form, once the liquid crystal state of the polymerizable liquid crystal composition contained in the dry film is a nematic liquid crystal phase, the nematic liquid crystal phase is transferred to a smectic liquid crystal phase.

In order to form a smectic liquid crystal phase via the nematic liquid crystal phase in this way, for example, the polymerizable liquid crystal compound contained in the dry film is heated to a temperature or higher representing the nematic liquid crystal phase, and then the polymerizable liquid crystal compound is smectic liquid crystal. A method of cooling to a temperature representing a phase is adopted.

When the polymerizable liquid crystal compound in the dry film is a smectic liquid crystal phase or the polymerizable liquid crystal compound is a smectic liquid crystal phase via a nematic liquid crystal phase, by measuring the phase transition temperature of the polymerizable liquid crystal compound used, Conditions for controlling the liquid crystal state (heating conditions) can be obtained. Measurement conditions for this phase transition temperature are described in the Examples herein.

Next, the polymerization step of the polymerizable liquid crystal compound will be described. Here, the photopolymerization initiator is contained in the composition for forming a polarizing film, the liquid crystal state of the polymerizable liquid crystal compound in the dry film is a smectic liquid crystal phase, and then the liquid crystal state of the smectic liquid crystal phase is maintained while the polymerizable liquid crystal compound is The method for photopolymerizing is described in detail. In the photopolymerization, the light to be irradiated on the dry film is appropriate depending on the type of photopolymerization initiator or the type of the polymerizable liquid crystal compound (especially, the type of the polymerizable group of the polymerizable liquid crystal compound) and the amount thereof. It can be performed by light or active electron beam selected from the group consisting of visible light, ultraviolet light and laser light. Of these, ultraviolet light is preferred from the viewpoint of being easy to control the progress of the polymerization reaction and the fact that a device widely used in the art can be used as a device for photopolymerization. Therefore, it is preferable to select the type of the polymerizable liquid crystal compound or photopolymerization initiator contained in the composition for forming a polarizing film so that photopolymerization can be performed by ultraviolet light. Moreover, when superposing|polymerizing, the polymerization temperature can also be controlled by cooling a dry film by suitable cooling means together with ultraviolet light irradiation. By employing such a cooling means, if polymerization of the polymerizable liquid crystal compound can be performed at a lower temperature, even if a relatively low heat resistance is used for the above-described substrate, there is also an advantage that the present polarizing film can be suitably formed. On the other hand, it is also possible to obtain the present polarizing film patterned by masking or developing during photopolymerization.

By performing the photopolymerization as described above, the polymerizable liquid crystal compound is polymerized while maintaining a nematic liquid crystal phase, a smectic liquid crystal phase, and preferably a higher order smectic liquid crystal phase as exemplified above, to form a polarizing film. The polarizing film obtained by polymerizing the polymerizable liquid crystal compound while maintaining the liquid crystal state of the smectic liquid crystal phase maintains a conventional host guest-type polarizing film, that is, a nematic liquid crystal state, depending on the action of the dichroic dye 1 Compared to a polarizing film obtained by polymerizing a polymerizable liquid crystal compound or the like in one, there is an advantage that the polarization performance is high. In addition, there is an advantage that the strength is excellent compared to the application of only the lyotropic dichroic dye.

The thickness of the polarizing film thus formed is preferably 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 obtained polarizing film. On the other hand, the thickness of the polarizing film is determined by measurement of an interference film thickness meter, a laser microscope, or a tactile film thickness meter.

The polarizing film thus formed is particularly preferable as long as the Bragg peak is obtained in the X-ray diffraction measurement as described above. As this main polarizing film in which such a Bragg peak is obtained, the main polarizing film which shows a diffraction peak originating in a hexatic phase or a crystal phase is mentioned, for example.

This polarizing film has a maximum absorption wavelength (λmax1) of 400 to 520 nm. The maximum absorption wavelength (λmax1) is preferably in the range of 430 to 520 nm, and more preferably in the range of 440 to 510 nm. Moreover, it is preferable that the absorption maximum wavelength (λmax1) of this polarizing film is shifted by a longer wavelength than the absorption maximum wavelength (λmax2) of the dichroic dye used in the production of this polarizing film. This absorption maximum wavelength (λmax2) was measured by preparing a solution in which a dichroic dye was dissolved in a suitable solvent, and in this solution state. The solvent that dissolves the dichroic dye is capable of sufficiently dissolving the dichroic dye, and one having no absorption in wavelength light of 350-550 nm is selected. The expression of such a long wavelength shift, when the dichroic dye (1) is dispersed between the molecular chains formed of the polymerizable liquid crystal compound in the present polarizing film, the dichroic dye (1) strongly interacts with the molecular chain It is present. On the other hand, the long-wavelength shift means that the difference (λmax1-λmax2) of the maximum absorption wavelength is a positive value, and the difference is preferably 20 nm or more, and more preferably 30 nm or more.

In addition, this polarizing film has a high dichroic ratio and very excellent polarization performance. Specifically, the dichroic ratio is usually 15 or more, and preferably 25 or more.

<Continuous manufacturing method of this polarizing film>

In the above, although the outline of the manufacturing method of this polarizing film was demonstrated, when manufacturing this polarizing film commercially, the method which can manufacture this polarizing film continuously is calculated|required. Such a continuous manufacturing method is based on a RolltoRoll type, and is sometimes referred to as a "main manufacturing method" in some cases. In addition, in this manufacturing method, it demonstrates centering around the case where a base material is a transparent base material. When the base material is a transparent base material, what is finally obtained is a polarizer having a transparent base material and a main polarizing film (hereinafter, referred to as "main polarizer" in some cases).

The manufacturing method is, for example,

A step of preparing a first roll in which a transparent substrate is wound around a first winding,

The step of continuously transmitting the transparent substrate from the first roll,

A step of continuously forming an alignment film on the transparent substrate,

A step of continuously applying a composition for forming a polarizing film on the alignment film,

A step of continuously forming a dry film on the alignment film by drying the applied polarizing film forming composition under conditions in which the polymerizable liquid crystal compound is not polymerized,

After making the polymerizable liquid crystal compound contained in the dry film into a nematic liquid crystal phase, preferably a smectic liquid crystal phase, and then maintaining the smectic liquid crystal phase, polymerizing the polymerizable liquid crystal compound, the polarizing film is continuously The process to obtain a polarizer,

It has the process of winding this polarizer obtained continuously in a 2nd winding core, and obtaining a 2nd roll. Here, with reference to FIG. 1, the manufacturing method of this manufacturing method is demonstrated especially regarding the case where an optical alignment film is used as an alignment film.

The first roll 210 on which the transparent substrate is wound around the first winding core 210A is readily available, for example, from the market. Examples of the transparent substrate that can be obtained in the market in the form of such a roll include films made of cellulose ester, cyclic olefin resin, polyethylene terephthalate, polycarbonate or polymethacrylic acid ester among the transparent substrates already exemplified. Moreover, when using this polarizing film as a circular polarizing plate, the transparent base material previously provided with the phase difference property can also be obtained easily from a market, For example, a phase difference film etc. which consist of a cellulose ester or a cyclic olefin resin.

Subsequently, the transparent substrate is released from the first roll 210. The method of releasing the transparent substrate is performed by providing suitable rotating means on the core 210A of the first roll 210 and rotating the first roll 210 by the rotating means. In addition, an auxiliary roll 300 suitable for the direction in which the transparent substrate is conveyed from the first roll 210 is provided, and the transparent substrate can be released by means of rotating the auxiliary roll 300. Further, both the first winding core 210A and the auxiliary roll 300 may be provided with a rotating means to release the transparent substrate while imparting an appropriate tension to the transparent substrate.

When the transparent substrate released from the first roll 210 passes through the coating device 211A, a composition for forming a photo-alignment layer is coated on the surface by the coating device 211A. In order to continuously apply the composition for forming the photo-alignment layer as described above, a printing method such as a gravure coating method, a die coating method, or a flexo method is performed by the coating device 211A as described above.

The transparent base material which has passed through the coating device 211A is conveyed to the drying furnace 212A, heated by the drying furnace 212A, and continuously forms a first dry film on the transparent base material. As the drying furnace 212A, for example, a hot air type drying furnace or the like is used. The set temperature of the drying furnace 212A is determined according to the kind of solvent contained in the composition for forming the photo-alignment layer applied by the coating device 211A. Further, the drying furnace 212A may be divided into a plurality of zones, and may have a format in which a set temperature is different for each of the divided zones, or a plurality of drying furnaces may be arranged in series to form a drying furnace having a different set temperature for each drying furnace.

The first dry film continuously formed by passing through the heating furnace 212A is then irradiated with polarized UV to the surface of the first dry film side or the surface of the transparent substrate by the polarized UV irradiation device 213A, and the first dry film The film forms an (optical) alignment film. At this time, the angle formed by the transport direction D1 of the transparent substrate and the alignment direction D2 of the photo-alignment film formed may intersect. Fig. 2 is a schematic view showing the relationship between the alignment direction D2 of the photo-alignment film formed after polarized UV irradiation and the transport direction D1 of the transparent substrate. That is, FIG. 2 shows that when the surface of the first stacked body after passing through the polarized UV irradiation device 213A is seen when the transport direction D1 of the transparent substrate and the alignment direction D2 of the photo-alignment film are formed, the angles formed by them represent approximately 45°. have.

In this way, the transparent substrate (first layered product) on which the photo-alignment film is continuously formed is then passed through the coating device 211B, and then the composition for forming the polarizing film is coated on the photo-alignment film, and then passes through the drying furnace 212B. By passing through the drying furnace 212B, the polymerizable liquid crystal compound contained in the polarizing film forming composition forms a nematic liquid crystal phase, preferably a smectic liquid crystal phase, and a second dry film is formed.

The transparent substrate that has passed through the drying furnace 212B has sufficiently removed the solvent contained in the composition for forming a polarizing film, so that the polymerizable liquid crystal compound in the second dry film is a nematic liquid crystal phase, preferably a liquid crystal state of the smectic liquid crystal phase. It is conveyed to the light irradiation device 213B while holding. By light irradiation by the light irradiation device 213B, the polymerizable liquid crystal compound is photopolymerized while maintaining the liquid crystal state, and the polarizing film is continuously formed on the alignment film to obtain the polarizer.

The polarizer formed continuously in this way is in the form of a laminate including a transparent substrate and an alignment film, and is wound around a second winding core 220A, thereby obtaining a form of the second roll 220. When the formed second polarizing film is wound to obtain a second roll, co-winding using a suitable spacer may be performed.

Thus, the transparent base material is in the order of the first roll/applying device 211A/drying furnace 212A/polarizing UV irradiating device 213A/applying device 211B/drying furnace 212B/lighting irradiating device 213B By passing through, the polarizing film seen on the photo-alignment film on the transparent substrate is continuously formed to produce the polarizer.

In addition, in the present manufacturing method shown in FIG. 1, a method of continuously manufacturing the transparent substrate to the present polarizing film is shown, but, for example, the transparent substrate is first roll/applying device 211A/drying furnace 212A/polarization The first stacked body continuously formed is wound around a winding core by passing through the UV irradiation device 213A in order, the first stacked body is manufactured in the form of a roll, and the first stacked body is unwound and released from the roll. The polarizer may be manufactured by passing the first laminate in the order of the coating device 211B/drying furnace 212B/light irradiation device 213B.

This polarizer obtained by this manufacturing method has a film shape and an elongated shape. When used in a liquid crystal display device or the like described later, this polarizer is cut and used to have a desired dimension according to a scale or the like of the liquid crystal display device.

As described above, although the configuration and manufacturing method of the polarizer seen in the form of a laminate of the transparent substrate/photo-alignment film/this polarizing film has been described, the polarizing film as seen above is obtained by peeling the photo-alignment film or the transparent substrate from the polarizer. It can also be obtained in a single layer. Moreover, you may make it the form which laminated|stacked the layer or film other than a transparent base material/light-alignment film/this polarizing film to this polarizer. As these layers and films, as described above, a retardation film may be further provided, or an antireflection layer or a brightness enhancement film may be further provided.

Further, by using the transparent substrate itself as a retardation film, a circular polarizing plate or an elliptical polarizing plate in the form of a retardation film/light alignment film/this polarizing film can also be used. For example, in the case of using a 1/4 wavelength plate uniaxially stretched as a retardation film, it is possible to manufacture a circular polarizing plate with RolltoRoll by setting the irradiation direction of polarized UV to be approximately 45° with respect to the conveying direction of the transparent substrate. It is preferable that the quarter wave plate used when manufacturing the circular polarizing plate has a characteristic that the in-plane retardation value for visible light becomes smaller as the wavelength becomes shorter.

In addition, a 1/2-wave plate was used as a retardation film, and a linear polarizing plate roll set by shifting the angle between the slow axis and the absorption axis of the polarizing film was prepared, and a 1/4-wave plate was formed on the opposite side to the surface on which the polarizing film was formed. By further forming, it is also possible to form a circular circular polarizing plate.

<Use of this polarizing film>

This polarizing film can be used for various display devices. A display device is a device having a display element, and includes a light emitting element or a light emitting device as a light emitting source. 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 (for example, a field emission display device (FED), a surface field emission display device ( SED)), electronic paper (display device using electronic ink or electrophoretic elements, plasma display device, projection display device (such as a grating light valve (GLV) display device, a display device having a digital micromirror device (DMD))) and piezoelectric And ceramic displays, etc. The liquid crystal display device 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 type liquid crystal display device. A display device displaying a two-dimensional image may be used, or a three-dimensional display device displaying a three-dimensional image may be used.

In particular, the polarizing film can be effectively used for a display device of an organic electroluminescence (EL) display device or an inorganic electroluminescence (EL) display device.

FIG. 3 is a schematic diagram showing a cross-sectional configuration of a liquid crystal display device (hereinafter referred to as "this liquid crystal display device" in some cases) using the polarizing film. The liquid crystal layer 17 is sandwiched by two substrates 14a and 14b.

6 and 10 are schematic diagrams showing the cross-sectional configuration of an EL display device (hereinafter referred to as "the present EL display device" in some cases) using the present polarizing film.

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

First, the liquid crystal display device 10 shown in Fig. 3 will be described.

A color filter 15 is disposed on the liquid crystal layer 17 side of the substrate 14a. The color filter 15 is disposed at a position facing the pixel electrode 22 with the liquid crystal layer 17 interposed therebetween, and the black matrix 20 is arranged at a position facing the boundary between the pixel electrodes. The transparent electrode 16 is disposed on the liquid crystal layer 17 side so as to cover the color filter 15 and the black matrix 20. On the other hand, an overcoat layer (not shown) may be provided between the color filter 15 and the transparent electrode 16.

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

Glass substrates and plastic substrates are used as the substrates 14a and 14b. As such a transparent substrate used for manufacturing the polarizing film, a glass substrate or a plastic substrate can be employed that is the same material as exemplified. Further, the transparent substrate 1 of the polarizing film may also serve as the substrate 14a and the substrate 14b. When a process of heating at a high temperature is required when manufacturing the color filter 15 or the thin film transistor 21 formed on the substrate, a glass substrate or a quartz substrate is preferable.

As the thin film transistor, an optimum one may be employed depending on 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 plastic substrate. In order to further downsize the liquid crystal display device, a driver IC may be formed on the substrate 14b.

A liquid crystal layer 17 is disposed between the transparent electrode 16 and the pixel electrode 22. Spacers 23 are disposed on the liquid crystal layer 17 in order to maintain a constant distance between the substrate 14a and the substrate 14b. On the other hand, although shown in FIG. 3 as a columnar spacer, the spacer is not limited to the columnar shape, and the shape is arbitrary as long as the distance between the substrate 14a and the substrate 14b can be kept constant.

Each member includes a substrate 14a, a color filter 15 and a black matrix 20, a transparent electrode 16, a liquid crystal layer 17, a pixel electrode 22, an interlayer insulating film 18 and a thin film transistor 21, And the substrates 14b.

Among the substrates 14a and 14b with the liquid crystal layer 17 interposed therebetween, polarizers 12a and 12b are provided on the outside of the substrate 14b, and a polarizer viewed from at least one of them is used. .

Moreover, it is preferable if retardation layers (for example, 1/4 wavelength plate or optical compensation film) 13a and 13b are laminated. Among the polarizers 12a and 12b, by disposing the polarizer in the polarizer 12b, the function of converting incident light into linearly polarized light can be provided to the liquid crystal display device 10. On the other hand, the retardation films 13a and 13b may not be disposed depending on the structure of the liquid crystal display device or the type of liquid crystal compound contained in the liquid crystal layer 17, and the transparent substrate is a retardation film, and the original including the present polarizing film. In the case of using a polarizing plate, since the retardation film can be used as a retardation layer, the retardation layers 13a and/or 13b in FIG. 3 can be omitted. A polarizing film may be further provided on the light output side (outside) of the polarizer including the polarizing film.

Further, an antireflection film for preventing reflection of external light may be disposed outside the polarizer including the present polarizing film (when a polarizing film is further provided on the polarizing film).

As described above, the polarizer seen in the polarizer 12a or 12b of the liquid crystal display device 10 of FIG. 3 can be used. There is an effect that thinning of the liquid crystal display device 10 can be achieved by using the polarizer for the polarizers 12a and/or 12b.

When this polarizer is used for the polarizer 12a or 12b, the lamination order is not specifically limited. This will be described with reference to enlarged views of parts A and B surrounded by the dotted line in FIG. 3.

4 is an enlarged schematic cross-sectional view of part A of FIG. 3. 4(A1), when the present polarizer 100 is used as the polarizer 12a, the polarizing film 3, the photo-alignment film 2, and the transparent substrate 1 viewed from the retardation layer 13a side are in this order. It shows that it is installed to be arranged. Moreover, FIG. 4(A2) shows that the transparent base material 1, the photo-alignment film 2, and the present polarizing film 3 are provided in this order from the retardation layer 13a side.

5 is an enlarged schematic view of part B of FIG. 3. In (B1) of FIG. 5, when the present polarizer 100 is used as the polarizer 12b, the transparent substrate 1, the photo-alignment film 2, and the present polarizing film 3 are in this order from the retardation film 13b side. It is installed to be placed. In (B2) of FIG. 5, when the present polarizer 100 is used as the polarizer 12b, the polarizing film 3, the photo-alignment film 2, and the transparent substrate 1 viewed from the retardation film 13b side are in this order. It is installed to be placed.

A backlight unit 19, which is a light emitting source, is disposed outside the polarizer 12b. The backlight unit 19 includes a light source, a light guide, a reflector, a diffusion sheet, and a viewing angle adjustment sheet. Examples of light sources include electroluminescence, cold cathode tubes, hot cathode tubes, light emitting diodes (LEDs), laser light sources, and mercury lamps. In addition, the type of the polarizing film seen according to the characteristics of the light source can be selected.

When the liquid crystal display device 10 is a transmissive liquid crystal display device, the white light generated from the light source in the backlight unit 19 enters the light guide body, and the course is changed by the reflector to diffuse in the diffusion sheet. The diffused light enters the polarizer 12b from the backlight unit 19 after being adjusted to have a desired directivity by the viewing angle adjustment sheet.

Of the incident light which is unpolarized light, only one linearly polarized light passes through the polarizer 12b of the liquid crystal panel. The linearly polarized light is converted into circularly polarized or elliptically polarized by the phase difference layer 13b, and sequentially passes through the substrate 14b, the pixel electrode 22, and the like to reach the liquid crystal layer 17.

Here, the presence or absence of a potential difference between the pixel electrode 22 and the opposing transparent electrode 16 changes the alignment state of the liquid crystal molecules included in the liquid crystal layer 17, and the light emitted from the liquid crystal display device 10 The luminance of is controlled. When the liquid crystal layer 17 is in an alignment state that converts and transmits polarized light, the polarized light passes through the liquid crystal layer 17 and the transparent electrode 16, and light in a specific wavelength range passes through the color filter 15. The polarizer 12a is reached, and the liquid crystal display device brightly displays the color determined by the color filter.

Conversely, when the liquid crystal layer 17 is in an alignment state that transmits polarized light as it is, the light transmitted through the liquid crystal layer 17, the transparent electrode 16, and the color filter 15 is absorbed by the polarizer 12a. Thereby, this pixel displays black. In the intermediate alignment state between these two states, since the luminance of light emitted from the liquid crystal display device 10 is also in the middle of both, the pixel displays an intermediate color.

When the present liquid crystal display device 10 is a semi-transmissive liquid crystal display device, it is preferable to use one in which a quarter wave plate is further laminated (circular polarizing plate) on the main polarizing film side of the polarizer. At this time, the pixel electrode 22 has a transmission portion formed of a transparent material and a reflection portion formed of a material that reflects light, and in the transmission portion, an image is displayed in the same manner as the transmission liquid crystal display described above. On the other hand, in the reflection unit, external light enters the liquid crystal display device, and the circularly polarized light transmitted through the polarizing film through the action of the 1/4 wavelength plate further provided in the polarizing film passes through the liquid crystal layer 17, and the pixel electrode ( It is reflected by 22) and used for display.

Next, this EL display device 30 using the present polarizing film will be described with reference to FIG. When using this polarizing film for this EL display device, it is preferable to use this polarizing film after making it into a circularly polarizing plate (hereinafter referred to as "this circularly polarizing plate" in some cases). There are two embodiments of this circular polarizing plate. Therefore, before explaining the configuration and the like of the EL display device 30, two embodiments of the circular polarizing plate will be described with reference to FIG.

7A is a cross-sectional view schematically showing a first embodiment of the circular polarizing plate 110. This 1st Embodiment is this circular polarizing plate 110 which further formed the retardation layer (phase difference film) 4 on this polarizing film 3 in this polarizer 100. 7B is a schematic diagram showing a second embodiment of the circular polarizing plate 110. In the second embodiment, the transparent substrate 1 itself is retarded by using the transparent substrate 1 (phase difference film 4), which is provided with a retardation property in advance to the transparent substrate 1 used when manufacturing the polarizer. It is the original polarizing plate 110 which has a function as a layer (4).

As the present circularly polarizing plate including the present polarizing film, the second embodiment of the above-mentioned circularly polarizing plate is preferable because the configuration is simple, and in this case, it is preferable to use a quarter wave plate as a transparent substrate, and furthermore, a transparent substrate. It is preferable if a quarter wave plate is used as and the requirements of (A1) and (A2) below are satisfied.

(A1) the angle between the absorption axis of the polarizing film and the slow axis of the quarter wave plate should be approximately 45°;

(A2) The value of the front retardation of the quarter wave plate measured at light having a wavelength of 550 nm should be in the range of 100 to 150 nm.

Here, the manufacturing method of this circular polarizing plate 110 is demonstrated. As described above, the second embodiment of the circular polarizing plate 110, in the present manufacturing method for manufacturing the present polarizer 100, the transparent substrate 1, which is previously provided with retardation property as the transparent substrate 1, that is, the retardation film It can manufacture by using. In the first embodiment of the circular polarizing plate 110, a retardation layer 4 may be formed by bonding a retardation film on the polarizing film 3 produced by the production method B. On the other hand, in the case of manufacturing the polarizing film 100 in the form of the second roll 220 by the present manufacturing method B, the polarizing film 100 seen from the second roll 220 is unwound, and predetermined dimensions are obtained. After being cut into, the circular polarizing plate having a film-like shape and an elongated shape may be prepared by preparing a third roll in which the retardation film is wound around the core, although it may be in the form of bonding the retardation film to the cut polarizing film 100. 110) may be continuously produced.

A method of continuously manufacturing the first embodiment of the circular polarizing plate 110 will be described with reference to FIG. 8. This manufacturing method,

A process of releasing the polarizing film 100 continuously viewed from the second roll 220, and continuously releasing the retardation film from the third roll 230 on which the retardation film is wound;

A process of forming the original polarizing plate 110 by continuously bonding the polarizing film formed on the polarizing film 100 released from the second roll 220 and the retardation film released from the third roll,

The formed circular polarizing plate 110 is wound on a fourth winding core 240A, and is made of a process of obtaining a fourth roll 240.

As described above, the manufacturing method of the first embodiment of the circular polarizing plate 110 has been described. However, when bonding the retardation film with the polarizing film 3 in the polarizer 100, an adhesive formed by this adhesive is used using a suitable adhesive. The polarizing film 3 viewed through the layer and the retardation film may be bonded.

Next, this EL display device provided with the original polarizing plate 110 will be described again with reference to FIG. 6.

In the EL display device 30, an organic functional layer 36 and a cathode electrode 37, which are light emission sources, are stacked on a substrate 33 on which a pixel electrode 35 is formed. The circular polarizing plate 31 is disposed on the opposite side to the organic functional layer 36 with the substrate 33 interposed therebetween, and the circular polarizing plate 110 is used as the circular polarizing plate 31. The organic functional layer 36 emits light by applying a positive voltage to the pixel electrode 35 and a negative voltage to the cathode electrode 37 and applying a direct current between the pixel electrode 35 and the cathode electrode 37. The organic functional layer 36, which is a light emission source, is composed of an electron transport layer, a light emitting layer, and a hole transport layer. The light emitted from the organic functional layer 36 passes through the pixel electrode 35, the interlayer insulating film 34, the substrate 33, and the circular polarizing plate 31 (this original polarizing plate 110). The organic EL display device having the organic functional layer 36 will be described, but it may be applied to an inorganic EL display device having an inorganic functional layer.

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

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

When this circularly polarizing plate 110 is used as the circularly polarizing plate 31, the lamination order will be described with reference to an enlarged view of the portion C surrounded by the dotted line in FIG. When the circularly polarizing plate 110 is used as the circularly polarizing plate 31, the retardation layer 4 in the circularly polarizing plate 110 is disposed on the substrate 33 side. Fig. 9(C1) is an enlarged view using the first embodiment of the circular polarizing plate 110 as the circular polarizing plate 31, and Fig. 9(C2) shows the second embodiment of the circular polarizing plate 110. It is an enlarged view used as the polarizing plate 31.

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

As the substrate 33, ceramic substrates such as a sapphire glass substrate, a quartz glass substrate, a soda glass substrate, and alumina; Metal substrates such as copper; And plastic substrates. Although not shown, a thermally conductive film may be formed on the substrate 33. A diamond thin film (DLC, etc.) etc. are mentioned as a heat conductive film. When the pixel electrode 35 is of a reflective type, light is emitted in a direction opposite to the substrate 33. Therefore, not only transparent materials, but also non-transparent materials such as stainless steel can be used. The substrate may be formed singly or may be formed as a laminated substrate by bonding a plurality of substrates with an adhesive. Moreover, these board|substrates are not limited to what is a plate shape, but a film may be sufficient.

As the thin film transistor 40, a polycrystalline silicon transistor or the like may be used, for example. The thin film transistor 40 is provided at the end of the pixel electrode 35, and its size is about 10 to 30 µm. On the other hand, 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 a function of electrically connecting to the pixel electrode 35 to suppress the resistance value, and in general, the wiring electrode is Al, Al and transition metal (except Ti), Ti or nitride Any one or two or more of titanium (TiN) is used.

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

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

Next, an EL element comprising a pixel electrode 35 as a transparent electrode, an organic functional layer 36 as a light emission source, and a cathode electrode 37 will be described. The organic functional layer 36 has at least one hole transport layer and a light emitting layer, respectively, for example, an electron injection transport layer, a light emitting layer, a hole transport layer, and a hole injection layer sequentially.

Examples of the pixel electrode 35 include ITO (tin-doped indium oxide), IZO (zinc-doped indium oxide), IGZO, ZnO, SnO ₂ and In ₂ O ₃ , and the like, particularly ITO or IZO. The thickness of the pixel electrode 35 may have a thickness equal to or greater than a predetermined level capable of sufficiently injecting holes, and is preferably about 10 to 500 nm.

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

As the constituent material of the cathode electrode 37, 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. In order to improve the operational stability, it is preferable to use a two-component or three-component alloy system selected from the illustrated metal elements. Examples of the alloy system include 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) ∼20 at%) and the like are preferred.

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

The hole injection layer has a function of facilitating injection of holes from the pixel electrode 35, and the hole transport layer has a function of transporting holes and a function of interfering 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 transport layer are not particularly limited and vary depending on the formation method, but are preferably about 5 to 100 nm. Various organic compounds can be used for the hole injection layer and the hole transport layer. In order to form a hole injection transport layer, a light emitting layer, and an electron injection transport layer, a vacuum deposition method can be used in that a homogeneous thin film can be formed.

As the organic functional layer 36, which is a light emission source, using light emission (fluorescence) from singlet excitons, using light emission (phosphorescence) from triplet excitons, using light emission (fluorescence) from singlet excitons and triplet excitons Using light emission (phosphorescence) from, including those formed by organic substances, those formed by organic substances and those formed by inorganic substances, including polymer materials, low-molecular materials, high-molecular materials and low-molecular materials. Can be used. However, the present invention is not limited to this, and the organic functional layer 36 using various known ones for EL elements can be used in the present EL display device 30.

A desiccant 38 is disposed in the space between the cathode electrode 37 and the sealing lid 39. This is because the organic functional layer 36 is weak to humidity. The desiccant 38 absorbs moisture to prevent deterioration of the organic functional layer 36.

10 is a schematic diagram showing a cross-sectional configuration of another aspect of the EL display device 30. As shown in FIG. This EL display device 30 has a sealing structure using a thin film sealing film 42, and it is also possible to obtain emitted light from the opposite side of the array substrate.

As the thin film sealing film 42, it is preferable to use a DLC film obtained by depositing DLC (diamond-like carbon) on a film of an electrolytic capacitor. The DLC film has a property that water permeability is very poor and has high moisture-proof performance. Further, a DLC film or the like may be formed by directly depositing the surface of the cathode electrode 37. Further, the thin resin film and the metal thin film may be stacked in multiple layers to form a thin film sealing film 42.

As described above, a novel display device (this liquid crystal display device and this EL display device) provided with the present polarizing film, the present polarizer, the original polarizing plate, and the present polarizing film is provided.

Finally, the projection type liquid crystal display device using this polarizing film is demonstrated.

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

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

The bundle of light rays emitted from the light source (for example, a high-pressure mercury lamp) 111, which is a light emission source, firstly includes a first lens array 112, a second lens array 113, a polarization conversion element 114, and a superposition lens 115. By passing, uniformity of luminance and polarization of anti-ray bundles are achieved.

Specifically, the bundle of light beams emitted from the light source 111 is divided into a plurality of small bundles of light beams by the first lens array 112 in which the minute lenses 112a are formed in a matrix form. The second lens array 113 and the overlapping lens 115 are provided to irradiate all three liquid crystal panels 140R, 140G, and 140B, each of which is a target of illumination, and thus each liquid crystal panel incident side surface The whole silver becomes almost uniform roughness.

The polarization conversion element 114 is constituted by a polarization beam splitter array, and is disposed between the second lens array 113 and the overlapping lens 115. Accordingly, the random polarization from the light source is converted into polarized light having a specific polarization direction in advance, thereby reducing the amount of light loss at the incident side polarizer, which will be described later, and serves to improve the brightness of the screen.

As described above, the luminance uniformized and polarized light is sequentially red channel, green channel, and blue channel by dichroic mirrors 121, 123, and 132 for separating into three primary colors of RGB via the reflection mirror 122. Separated by, and enters the liquid crystal panel (140R, 140G, 140B), respectively.

In the liquid crystal panels 140R, 140G, and 140B, polarizers 142 are disposed on the incident side, and polarizers 143 are disposed on the exit side, respectively. The polarizing film seen in the polarizer 142 and the polarizer 143 can be used.

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

The polarizing film 100 is useful as a polarizing film having excellent durability in an optical path such as a blue channel, a green channel, and a red channel by selecting the type of a dichroic dye suitable for a corresponding channel.

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

Electronic papers are those represented by molecules such as optical anisotropy and dye molecular orientation, those represented by particles such as electrophoresis, particle movement, particle rotation, phase change, those displayed by one end of the film moving, What is indicated by a color change/phase change, what is shown by light absorption of a molecule, what is shown by self-lighting when electrons and holes are combined, etc. are mentioned. More specifically, microcapsule type electrophoresis, horizontally movable electrophoresis, vertically movable electrophoresis, spherical twisted ball, magnetically twisted ball, circumferentially twisted ball method, charged toner, electron powder fluid, magnetophoretic type, magnetic direct heating, electro Wetting, light scattering (transparent/cloudy change), cholesteric liquid crystal/photoconductive layer, cholesteric liquid crystal, bistable nematic liquid crystal, ferroelectric liquid crystal, dichroic dye/liquid crystal dispersion type, movable film, color repelling by leuco dye, Photochromic, electrochromic, electrodeposition, flexible organic EL, and the like. The electronic paper may be used not only for personal use of text or images, but also used for advertisement signs and the like. According to this polarizing film, the thickness of the electronic paper can be made thin.

As a stereoscopic display device, a method of arranging different phase difference films alternately such as a micropole method has been proposed (Japanese Patent Laid-Open No. 2002-185983), but patterning by printing, inkjet, photolithography, etc. is possible using this polarizing film. Since it is easy, the manufacturing process of a display device can be shortened, and a retardation film is unnecessary.

Example

Hereinafter, the present invention will be described in more detail by examples. "%" and "part" in the examples are mass% and mass parts, unless otherwise specified.

Example 1 [Preparation of compound (1A) (compound represented by (1A) below)]

Compound (1A) was synthesized by the following scheme.

A compound represented by formula (1B) [Compound (1B)] 5.00 g, 4-hydroxyethyl benzoate 4.63 g, dimethylaminopyridine (DMAP) 0.23 g and 25 g of chloroform were mixed, and in a light-shielding nitrogen atmosphere, 5°C The mixture was stirred for 10 minutes. To the obtained mixture solution, 2.58 g of diisopropylcarbodiimide (IPC) was added dropwise over 5 minutes and stirred for 4 hours. To the obtained reaction solution, 75 g of methanol was added, crystallized, and the crystal was filtered. After further washing the crystals with the same amount of methanol, 6.78 g of compound (1A) was obtained by vacuum drying. The yield was 87% based on compound (1B).

¹ H-NMR (CDCl ₃ ) of compound (1A): δ (ppm) 1.41 (t, 3H), 3.12 (s, 6H), 4.40 (m, 2H), 6.76 (m, 2H), 7.33 (m, 2H), 7.93 (dd, 4H), 8.15 (m, 2H), 8.30 (m, 2H).

Example 2 [Compound (1D) (compound represented by (1D) below)]

Compound (1D) was synthesized by the following scheme.

5.00 g of compound (1B), 4.63 g of 4-butyloxyphenol, 0.23 g of DMAP and 25 g of chloroform were mixed and stirred at 5°C for 10 minutes in a light-shielding/nitrogen atmosphere. 2.58 g of IPC was added dropwise to the obtained mixed solution over 5 minutes, and further stirred for 4 hours. 75 g of methanol was added to the obtained reaction solution, crystallized, and the crystal was filtered. The crystal was dissolved in 50 g of dimethylacetamide, and the insoluble matter was filtered through celite. The filtrate was recovered and crystallized with water. The obtained crystals were also dissolved in 50 g of tetrahydrofuran to remove insoluble matters by filtration, then heptane was added and crystallized to obtain 4.66 g of compound (1D) by vacuum drying. The yield was 60% based on compound (1B).

¹ H-NMR (CDCl ₃ ) of compound (1D): δ (ppm) 0.99 (t, 3H), 1.45 (m, 2H), 1.78 (m, 2H), 3.12 (s, 6H), 3.98 (t, 2H), 6.77 (m, 2H), 6.93 (m, 2H), 7.15 (m, 2H), 7.92 (dd, 4H), 8.29 (dd, 2 H).

Examples (production of the present polarizing film, etc.) and reference examples

[Polymerizable liquid crystal compound]

As a polymerizable liquid crystal compound contained in the composition for forming a polarizing film, a compound represented by the following formula (2-6) [Compound (2-6)], a compound represented by the following formula (2-8) [Compound (2- 8)], the compound represented by the following formula (2-22) [Compound (2-22)] and the compound represented by the following formula (2-25) [Compound (2-25)] were used.

On the other hand, compound (2-6) is Lub et al. Recl. Trav. Chim. It was synthesized by the method described in Pays-Bas, 115, 321-328 (1996). Moreover, compound (2-8) was produced based on this method.

Compound (2-22) and compound (2-25) were prepared in accordance with the method described in Japanese Patent No. 4719156.

Compound (2-6):

(Measurement of phase transition temperature)

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

On the glass substrate on which the alignment film was formed, a film composed of compound (2-6) was formed and heated, and the phase transition temperature was confirmed by texture observation with a polarizing microscope (BX-51, manufactured by Olympus). The film composed of the compound (2-6) raises the temperature to 120° C., and when the temperature is lowered, phase transitions from 112° C. to the nematic phase, phase transitions from 110° C. to the smectic A phase, and smectic at 94° C. Phase transition to phase B.

Compound (2-8):

(Measurement of phase transition temperature)

The phase transition temperature of compound (2-8) was confirmed in the same manner as the measurement of the phase transition temperature of compound (2-6). Compound (2-8), after raising the temperature to 140°C, when lowering the temperature, phase-transfers to the nematic phase at 131°C, phase-transfers to the smectic A phase at 80°C, and smectic B phase at 68°C It was confirmed that the phase transition.

Compound (2-22):

(Measurement of phase transition temperature)

The phase transition temperature of compound (2-22) was confirmed in the same manner as the measurement of the phase transition temperature of compound (2-6). Compound (2-22), after raising the temperature to 140°C, when lowering the temperature, phase-transfers from 106°C to the nematic phase, phase-transfers from 103°C to the smectic A phase, and 86°C to the smectic B phase Phase transition.

Compound (2-25):

(Measurement of phase transition temperature)

The phase transition temperature of the compound (2-25) was confirmed in the same manner as the measurement of the phase transition temperature of the compound (2-6). When the temperature of the compound (2-25) is increased to 140° C. and then the temperature is lowered, the phase transitions from 119° C. to the nematic phase, phase transitions from 100° C. to the smectic A phase, and 77° C. to the smectic B phase. Phase transition.

Example 3

(Preparation of composition for polarizing film formation)

The composition (G) for polarizing film formation was obtained by mixing the following components and stirring at 80 degreeC for 1 hour.

Polymerizable liquid crystal compounds; Compound (2-6) 75 parts

Compound (2-8) 25 parts

Dichroic pigments; Compound (1A) 2.5 parts

Polymerization initiators; 2-Dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one (Irgacure 369; manufactured by Chiba Specialty Chemicals) 6 parts

Leveling agents; Polyacrylate compound (BYK-361N; manufactured by BYK-Chemie) 1.5 parts

solvent; 250 parts of toluene

(Measurement of phase transition temperature)

As in the case of compound (2-6) and compound (2-8), the phase transition temperature of the polymerizable liquid crystal composition contained in the composition (G) for polarizing film formation was determined. This polymerizable liquid crystal composition, after raising the temperature to 140°C, when lowering the temperature, phase-shifts from 115°C to the nematic phase, phase-shifts from 105°C to the smectic A phase, and smectic B phase at 75°C. Phase transition.

〔Production and evaluation of this polarizing film〕

1. Formation of alignment film

A glass substrate was used as a transparent substrate.

On a glass substrate, a 2 mass% aqueous solution (orientated polymer composition) of polyvinyl alcohol (polyvinyl alcohol 1000 completely saponified, manufactured by Wako Pure Chemical Industries, Ltd.) was applied by spin coating, dried, and then thick 100 A nm film was formed. Subsequently, an alignment film was formed by performing a rubbing treatment on the surface of the obtained film. The rubbing treatment was performed using a semi-automatic rubbing device (trade name: LQ-008 type, manufactured by Joyo Kogaku Co., Ltd.), and the indentation amount was 0.15 mm by cloth (trade name: YA-20-RW, manufactured by Yoshikawa Chemical Co., Ltd.). , 500 rpm, 16.7 mm/s. Through this rubbing treatment, a laminate 1 having an alignment film formed on a glass substrate was obtained.

2. Formation of polarizing film

On the alignment film of laminate 1, the composition (G) for forming a polarizing film was applied by a spin coat method, heated and dried on a hot plate at 120° C. for 1 minute, then rapidly cooled to room temperature, and dried on the alignment film. Formed. Subsequently, by using a UV irradiation apparatus (SPOT CURE SP-7; manufactured by Ushio Denki Co., Ltd.), ultraviolet rays are irradiated to the dry film at an exposure amount of 2000 mJ/cm 2 (based on 365 nm), whereby the polymerizability contained in the dry film The liquid crystal compound was polymerized while maintaining the liquid crystal state of the polymerizable liquid crystal composition, and a polarizing film was formed with the dried film to obtain a laminate 2.

The thickness of the polarizing film at this time was measured by a laser microscope (OLS3000 manufactured by Olympus Co., Ltd.), and was 1.7 µm.

3. X-ray diffraction measurement

About this main polarizing film of the obtained laminated body 2, X-ray diffraction measurement was performed using the X-ray diffraction apparatus X'Pert PRO MPD (made by Spectris Co., Ltd.). Using the Cu as the target, the X-ray generated under the conditions of the X-ray tube current of 40 mA and the X-ray tube voltage of 45 kV is obtained through the fixed divergence slit 1/2° (preliminarily, the rubbing direction of the alignment film under the polarizing film is obtained) ), and scanned by scanning in steps of 2θ=0.01671° in the range of scanning range 2θ=4.0 to 40.0°. As a result, a peak half-width (FWHM) of about 2θ=20.1° = about 0.31° sharp diffraction peak (Bragg) Peak) was obtained. Moreover, the same result was obtained also from the incidence from the rubbing vertical direction. It was found that the order period (d) obtained from the peak position was about 4.4 Hz, and that a structure reflecting the higher order smectic phase was formed.

4. Measurement of dichroic ratio

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

A ^{device in which} the absorbance in the direction of the transmission axis at the maximum absorption wavelength (A ¹ ) and the absorbance in the direction of the absorption axis (A ² ) are set in a spectrophotometer (UV-3150 manufactured by Shimadzu Corporation) with a polarizer. It measured using the double beam method. In the above folder, a mesh for cutting the amount of light by 50% was installed on the reference side. The ratio (A ² /A ¹ ) was calculated from the measured values of the absorbance in the direction of the transmission axis (A ¹ ) and the absorbance in the direction of the absorption axis (A ² ) to obtain a dichroic ratio. The maximum absorption wavelength (λmax1) was 506 nm, and the dichroic ratio at this wavelength was as high as 30. It can be said that a higher dichroic ratio is useful as a polarizing film. Further, it was found that the maximum absorption wavelength (λmax2) measured by using the dichroic dye used in the composition for forming a polarizing film as a solution was 450 nm, and that it was shifting a long wavelength. As a result of this long wavelength shift, when the compound (1A) is dispersed between the dense molecular chains formed by polymerization of the polymerizable liquid crystal compound in the present polarizing film, the compound (1A) strongly interacts with the molecular chain. It indicates that there is.

Example 4

This polarizing film was produced in the same manner as in Example 3 except that Compound (1B) was used instead of Compound (1A). Similarly, when the absorption maximum wavelength and the dichroic ratio were measured, the absorption maximum wavelength (λmax1) was 494 nm, and the dichroic ratio was high as 30. The maximum absorption wavelength (λmax2) of the dichroic dye solution was measured was 446 nm, and it was found that the long wavelength shift was observed. This result shows that the compound (1A) strongly interacts with the molecular chain when the compound (1A) is dispersed between dense molecular chains formed by polymerization of the polymerizable liquid crystal compound in the present polarizing film. will be.

Example 5

A polarizing film was produced in the same manner as in Example 3 except that Compound (2-22) was used instead of Compound (2-6) and Compound (2-25) was used instead of Compound (2-8). Similarly, when the absorption maximum wavelength and the dichroic ratio were measured, the absorption maximum wavelength (λmax1) was 500 nm, and the dichroic ratio was as high as 27. It was found that the absorption maximum wavelength (λmax2) measured by the dichroic dye solution was 450 nm and was shifting long wavelengths.

Example 6

A polarizing film was produced in the same manner as in Example 4 except that Compound (2-22) was used instead of Compound (2-6) and Compound (2-25) was used instead of Compound (2-8). Similarly, when the absorption maximum wavelength and the dichroic ratio were measured, the absorption maximum wavelength (λmax1) was 492 nm, and the dichroic ratio was high as 28. The maximum absorption wavelength (λmax2) of the dichroic dye solution was measured to be 446 nm, and it was found that the long wavelength shift was observed.

Example 7

A polarizing film was produced in the same manner as in Example 3 except that 100 parts of the polymerizable nematic liquid crystal compound (trade name LC242 manufactured by BASF) was used instead of the compound (2-6) and the compound (2-8). Similarly, when the absorption maximum wavelength and the dichroic ratio were measured, the absorption maximum wavelength (λmax1) was 464 nm and the dichroic ratio was 10. The maximum absorption wavelength (λmax2) of the dichroic dye solution was 450 nm.

Example 8

A polarizing film was produced in the same manner as in Example 4 except that 100 parts of polymerizable nematic liquid crystal (trade name LC242 manufactured by BASF) was used instead of compound (2-6) and compound (2-8). Similarly, when the absorption maximum wavelength and the dichroic ratio were measured, the absorption maximum wavelength was 462 nm and the dichroic ratio was 10. The maximum absorption wavelength (λmax2) of the dichroic dye solution was 446 nm.

Comparative Example 1

A polarizing film was produced in the same manner as in Example 3, except that the compound of "Pigment No. 5" described in Japanese Patent 1454637 was used instead of Compound (1A). Similarly, when the absorption maximum wavelength and the dichroic ratio were measured, the absorption maximum wavelength (λmax1) was 398 nm and the dichroic ratio was 20. The maximum absorption wavelength (λmax2) measured by the dichroic dye solution was 386 nm. The maximum absorption wavelength of this dichroic dye was 400 nm or less, and the long wavelength shift amount was small.

Compound of ``pigment number 5''

Comparative Example 2

A polarizing film was produced in the same manner as in Example 3, except that the compound of "Pigment No. 1" described in Japanese Patent 1454637 was used instead of Compound (1A). Similarly, when the absorption maximum wavelength and the dichroic ratio were measured, the absorption maximum wavelength was 446 nm and the dichroic ratio was 4. The maximum absorption wavelength (λmax2) measured by the dichroic dye solution was 436 nm. The dichroic ratio was low, and the long wavelength shift amount was small.

Compound of ``pigment number 1''

The novel compound of the present invention is very useful as a dichroic dye for manufacturing a polarizing film, and has high industrial value.

1: transparent substrate 2: light alignment film
3: present polarizing film 100: present polarizer
210: first roll 210A: winding core
220: second roll 220A: winding core
230: third roll 230A: winding core
240: fourth roll 240A: winding core
211A, 211B: Applicator 212A, 212B: Drying furnace
213A: polarized UV irradiation device 213B: light irradiation device
300: auxiliary roll 10: liquid crystal display device
12a, 12b: polarizer 13a, 13b: retardation layer
14a, 14b: Substrate 15: Color filter
16: transparent electrode 17: liquid crystal layer
18: interlayer insulating film 19: backlight unit
20: black matrix 21: thin film transistor
22: pixel electrode 23: spacer
30: EL display device 31: circular polarizing plate
32: retardation film 33: substrate
34: interlayer insulating film 35: pixel electrode
36: organic functional layer 37: cathode electrode
38: desiccant 39: sealing lid
40: thin film transistor 41: rib
42: thin film sealing film 44: EL display device
111: light source 112: first lens array
112a: lens 113: second lens array
114: polarization conversion element 115: superposition lens
121, 123, 132: dichroic mirror 122: reflective mirror
140R, 140G, 140B: liquid crystal panel 142, 143: polarizer
150: cross dichroic prism 170: projection lens
180: screen

Claims (16)

A polarizing film formed of a composition comprising a compound represented by formula (1) and a polymerizable liquid crystal compound, and exhibiting a higher order smectic phase.

[In Formula (1), Y is a group represented by Formula (Y1) or Formula (Y2).

(In the formula, L is an oxygen atom or -NR-, and R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.)
R ¹ is a group represented by formula (R ¹ -1), formula (R ¹ -2) or formula (R ¹ -3).

(In the formula, ma is an integer from 0 to 10, and when there are two ma in the same group, the two ma are the same or different from each other. * represents the number of bonds.)
R ² is the formula (R ² -1), the formula (R ² -2), the formula (R ² -3), the formula (R ² -4), the formula (R ² -5) or the formula (R ² -6) It is a group represented by.

(In the formula, mb is an integer from 0 to 10. * represents the number of bonds.)] The polarizing film according to claim 1, wherein the polymerizable liquid crystal compound is a polymerizable smectic liquid crystal compound exhibiting a higher order smectic phase. The polarizing film according to claim 1 or 2, which exhibits a smectic B phase. The polarizing film according to claim 1 or 2, wherein the maximum absorption wavelength (λmax1) of the polarizing film is shifted by a longer wavelength than the maximum absorption wavelength (λmax2) of the dichroic dye. The polarizing film according to claim 1 or 2, wherein a difference between the maximum absorption wavelength (λmax1) of the polarizing film and the maximum absorption wavelength (λmax2) of the dichroic dye is 20 nm or more. The polarizing film according to claim 1 or 2, wherein a black peak is obtained in X-ray diffraction measurement. The polarizing film according to claim 6, wherein the black peak is a peak derived from a plane periodic structure having a molecular orientation with a periodic interval of 3.0 to 5.0 kPa. A polarizer comprising the polarizing film according to claim 1 or 2, and a transparent substrate. A liquid crystal display device comprising the polarizing film according to claim 1 or 2. A circular polarizing plate comprising the polarizing film according to claim 1 or 2, and a quarter wave plate, which satisfies the following requirements (A1) and (A2).
(A1) the angle formed between the absorption axis of the polarizing film and the slow axis of the quarter wave plate is approximately 45°;
(A2) The value of the front retardation of the quarter wave plate measured in light having a wavelength of 550 nm is in the range of 100 to 150 nm. An organic EL display device comprising the circular polarizing plate according to claim 10 and an organic EL element. delete delete delete delete delete

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