KR20220149628A - Elliptical polarizing plate - Google Patents

Abstract

(Project) An elliptically polarizing plate in which an orientation defect or an optical axis shift is suppressed is provided.
(Solution) In the elliptically polarizing plate of the present invention, an alignment layer A, a retardation layer, an alignment layer B, and a polarizing layer are formed in this order on a transparent substrate, and the optical axes of the polarizing layer and the retardation layer are substantially parallel. No, the retardation layer is a film composed of a polymer of a polymerizable liquid crystal compound, the alignment layer B is a film having a thickness of 80 nm to 800 nm, and the polarizing layer is a polymer of a polymerizable liquid crystal compound The dichroic dye is orientating in the film|membrane comprised.

Description

Elliptical polarizing plate {ELLIPTICAL POLARIZING PLATE}

The present invention relates to an elliptically polarizing plate. Moreover, this invention also relates to the manufacturing method of the display apparatus provided with an elliptically polarizing plate, and an elliptically polarizing plate.

Optical films, such as a polarizing plate and a retardation plate, are used for a flat panel display device (FPD). As such a polarizing plate, the polarizing plate which consists of a polarizing layer and protective film by which dichroic dyes, such as iodine, were orientation-adsorbed to the polyvinyl alcohol-type resin film is widely used. As a retardation plate, the retardation plate which extended|stretched a cycloolefin-type resin film, a polycarbonate-type resin film, or a triacetyl cellulose-type resin film is widely known. With the recent thinning, a thin-film polarizing plate and retardation plate produced by applying a composition containing a polymerizable liquid crystal compound to a substrate have been developed. For example, Patent Document 1 discloses a retardation film exhibiting reverse wavelength dispersion, and Patent Document 2 discloses a polarizing layer exhibiting high polarization performance. Further, for further thinning, for example, Patent Document 3 has developed a technique for forming a polarizing layer and a retardation film through a protective layer. These polarizing layers and retardation layers are laminated on each other and used as an elliptically polarizing plate in many cases.

Japanese Patent Publication No. 2010-537955 Japanese Patent Publication No. 2013-101328 Japanese Patent Publication No. 2014-63143

However, the conventional elliptically polarizing plate obtained in this way had a problem that an orientation defect or an optical axis shift generate|occur|produced in a polarizing layer. The orientation defect of a polarizing layer impairs the function as an elliptically polarizing plate in a defect part. Moreover, the optical axis shift impairs the function as an elliptically polarizing plate.

As a result of the present inventors examining, it discovered that the polarizing plate by which the orientation defect and optical axis shift were suppressed could be provided.

An object of this invention is to provide the elliptically polarizing plate by which the orientation defect of a polarizing layer, and optical axis shift were suppressed.

That is, the present invention provides the following [1] to [13].

[1] An elliptically polarizing plate in which an alignment layer A, a retardation layer, an alignment layer B and a polarizing layer are formed in this order on a transparent substrate,

The optical axes of the polarizing layer and the retardation layer are not substantially parallel,

The retardation layer is a film composed of a polymer of a polymerizable liquid crystal compound,

The alignment layer B is a film having a thickness of 80 nm to 800 nm,

The polarizing layer is a film in which a dichroic dye is dispersed and oriented in a film composed of a polymer of a polymerizable liquid crystal compound.

Elliptical polarizer.

[2] The elliptically polarizing plate according to [1], wherein the transparent substrate, the alignment layer A, the retardation layer, the alignment layer B, and the average refractive index of the polarizing layer are all in the range of 1.4 to 1.7.

[3] The elliptically polarizing plate according to [1] or [2], wherein the refractive index difference between adjacent layers is 0.2 or less.

[4] The elliptically polarizing plate according to any one of [1] to [3], wherein an angle between the optical axis of the polarizing layer and the retardation layer is in the range of 40° to 50°.

[5] The elliptically polarizing plate according to any one of [1] to [4], wherein the alignment layer A and the alignment layer B are both photo alignment films.

[6] The elliptically polarizing plate according to any one of [1] to [5], wherein the alignment layer A and the alignment layer B are photo alignment films containing a cinnamoyl group.

[7] The elliptically polarizing plate according to any one of [1] to [6], wherein the alignment layer A and the alignment layer B are a photo alignment film containing a resin having a weight average molecular weight of 20000 to 50000.

[8] The elliptically polarizing plate according to any one of [1] to [7], wherein the polarizing layer is a film composed of a polymer in a smectic liquid crystal state.

[9] The elliptically polarizing plate according to any one of [1] to [8], wherein the dichroic dye is an azo dye.

[10] The elliptically polarizing plate according to any one of [1] to [9], wherein the retardation layer satisfies all of the following formulas.

100 nm < Re(550) < 160 nm... (One)

Re(450)/Re(550) ≤ 1.0... (2)

1.00 ≤ Re(650)/Re(550)... (3)

(Re(450), Re(550), and Re(650) represent in-plane retardation at wavelengths of 450 nm, 550 nm, and 650 nm, respectively.)

[11] A liquid crystal display device comprising the elliptically polarizing plate according to any one of [1] to [10].

[12] An organic EL display device comprising the elliptically polarizing plate according to any one of [1] to [11].

[13] On a transparent substrate,

The process (1) of apply|coating the composition containing an orientation material A and a solvent, and irradiating polarized UV light after drying to form an orientation layer A;

A step (2) of forming a retardation layer by coating a composition containing a polymerizable liquid crystal compound, a polymerization initiator and a solvent on the alignment layer A, drying it, and then irradiating it with UV to polymerize it in a liquid crystal state;

A step (3) of applying a composition containing an alignment material B and a solvent and irradiating polarized UV light after drying to form an alignment layer B;

An ellipse having a step (4) of forming a polarizing layer by coating a composition containing a polymerizable liquid crystal compound, a dichroic dye, a polymerization initiator and a solvent on the alignment layer B, drying it and then irradiating it with UV to polymerize it in a liquid crystal state A method for manufacturing a polarizing plate.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the elliptically polarizing plate by which the optical axis shift of a retardation layer and a polarizing layer and generation|occurrence|production of an orientation defect were suppressed.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail. In addition, the scope of the present invention is not limited to the embodiments described herein, and various changes can be made without impairing the spirit of the present invention.

The elliptically polarizing plate of the present invention is an elliptically polarizing plate in which an alignment layer A, a retardation layer, an alignment layer B, and a polarizing layer are formed in this order on a transparent substrate.

[Transparent material]

As a transparent base material, a glass base material and a film base material are mentioned, A film base material is preferable, and a long roll-shaped film is more preferable at the point which can be manufactured continuously.

As resin which comprises a film base material, For example, Polyolefin, such as polyethylene, a polypropylene, a norbornene-type polymer; Cyclic olefin resin; polyvinyl alcohol; polyethylene terephthalate; polymethacrylic acid ester; polyacrylic acid ester; Cellulose esters, such as a triacetyl cellulose, a diacetyl cellulose, and cellulose acetate propionate; polyethylene naphthalate; polycarbonate; polysulfone; polyether sulfone; polyether ketone; polyphenylene sulfide and polyphenylene oxide; Plastics, such as these are mentioned.

As a commercially available cellulose ester base material, "Fujitak Film" (manufactured by Fuji Photo Film Co., Ltd.); "KC8UX2M", "KC8UY" and "KC4UY" (above, manufactured by Konica Minolta Opto Co., Ltd.) and the like.

Commercially available cyclic olefin resins include "Topas" (registered trademark) (manufactured by Ticona (Germany)), "Aton" (registered trademark) (manufactured by JSR Corporation), and "ZEONOR" (registered trademark) , "ZEONEX" (registered trademark) (above, manufactured by Nippon Zeon Corporation) and "Apel" (registered trademark) (manufactured by Mitsui Chemicals Co., Ltd.). Such cyclic olefin resin can be formed into a film by well-known means, such as a solvent casting method and a melt extrusion method, and it can be set as a base material. A commercially available cyclic olefin-based resin substrate can also be used.

Commercially available cyclic olefin-based resin substrates include "Sucina" (registered trademark), "SCA40" (registered trademark) (above, manufactured by Sekisui Chemical Industry Co., Ltd.), "Zeonoa Film" (registered trademark) (Optess) Corporation make) and "Aton Film" (trademark) (made by JSR Corporation) are mentioned.

The thickness of the base material is preferably thin from the viewpoint of practical handling, but when it is too thin, the strength decreases and the workability tends to be inferior. The thickness of a base material is 5 micrometers - 300 micrometers normally, Preferably they are 20 micrometers - 200 micrometers.

[Orientation layer A (alignment film for forming retardation layer)]

On the transparent base material, the orientation layer A is formed first. The alignment layer A (or referred to as alignment film A) is a layer having an alignment control force that orients the polymerizable liquid crystal compound used for formation of the retardation layer in a desired direction.

The alignment layer A preferably has solvent resistance that does not dissolve by application of a liquid crystal compound described later, and has heat resistance in heat treatment for removal of a solvent or alignment of a polymerizable liquid crystal compound described later. Examples of the alignment film include a rubbing alignment film, a photo alignment film, and a groove alignment film having an uneven pattern or a plurality of grooves on the surface thereof. When applying to a long roll-shaped film, the photo-alignment film which causes an orientation control force by polarized light irradiation from the point which can control an orientation direction easily is preferable.

Such an alignment film facilitates alignment of the polymerizable liquid crystal compound. In addition, various orientations such as horizontal orientation, hybrid orientation, and oblique orientation can be controlled depending on the type of the alignment layer, rubbing conditions, and light irradiation conditions.

It is possible to use the orientation film as described in the orientation layer B mentioned later for the orientation layer A used in order to form retardation layer. The alignment layer B may be the same as or different from the alignment layer A.

The thickness of the orientation layer A is normally in the range of 10-10000 nm (0.01 micrometer - 10 micrometers), Preferably it is the range of 80-800 nm (0.08 micrometer - 0.8 micrometer), More preferably, it is 100-500 nm (0.1 µm to 0.5 µm). By forming the orientation layer A within this film thickness range, it is possible to suppress an orientation defect.

[phase difference layer]

The elliptically polarizing plate of the present invention has a retardation layer next to the alignment layer A. This retardation layer is formed by applying a composition containing a polymerizable liquid crystal compound (hereinafter also referred to as a composition for forming a retardation layer) on the alignment layer A to form a coating layer, and aligning the polymerizable liquid crystal compound in the coating layer. It is preferable to set it as a state, to polymerize and harden it in this state, and to set it as the layer which consists of a polymer at the point which can design arbitrarily thickness reduction and wavelength dispersion|distribution characteristic. In addition, the composition used for the formation of the retardation layer (hereinafter referred to as the composition for forming the retardation layer) may further include a solvent, a photopolymerization initiator, a photosensitizer, a polymerization inhibitor, a leveling agent and an adhesion improving agent. have.

The retardation layer in the elliptically polarizing plate of the present invention is usually obtained by applying a composition for forming a retardation layer to an alignment layer A formed on a substrate, and polymerizing a polymerizable liquid crystal compound contained in the composition for forming an optically anisotropic layer. is formed The retardation layer is usually a film having a thickness of 5 μm or less, which is cured in a state in which the polymerizable liquid crystal compound is oriented, preferably liquid crystal cured in a state in which the polymerizable liquid crystal compound is oriented in the horizontal direction with respect to the substrate surface. it's a curtain

The retardation layer cured in a state in which the polymerizable liquid crystal compound is oriented in the horizontal direction with respect to the substrate surface, R(λ), which is the in-plane retardation with respect to light having a wavelength of λ nm, satisfies the optical properties represented by the following formula (1) It is preferable, and it is more preferable to satisfy the optical characteristic shown by following formula (1), following formula (2), and following formula (3).

100 nm < Re(550) < 160 nm... (One)

(Wherein, Re(550) represents an in-plane retardation value (in-plane retardation) with respect to light having a wavelength of 550 nm.)

Re(450)/Re(550) ≤ 1.0... (2)

1.00 ≤ Re(650)/Re(550)... (3)

(Wherein, Re(450) is an in-plane retardation value for light with a wavelength of 450 nm, Re(550) is an in-plane retardation value for light with a wavelength of 550 nm, and Re(650) is for light with a wavelength of 650 nm. It represents the in-plane phase difference value.)

When "Re(450)/Re(550)" of the retardation layer exceeds 1.0, light leakage on the short wavelength side in the elliptically polarizing plate including the retardation layer becomes larger, so 1.0 or less is preferable, and more preferably 0.95 or less , more preferably 0.92 or less.

The in-plane retardation value of the retardation layer can be adjusted by the thickness of the retardation layer. Since the in-plane retardation value is determined by the following formula (4), in order to obtain a desired in-plane retardation value Re(λ)), Δn(λ) and the film thickness d may be adjusted. 0.5 micrometer - 5 micrometers are preferable and, as for the thickness of retardation layer, 1 micrometer - 3 micrometers are more preferable. The thickness of the retardation layer can be measured with an interference thickness meter, a laser microscope, or a stylus type thickness meter. In addition, Δn(λ) depends on the molecular structure of the polymerizable liquid crystal compound described later.

Re(λ) = d × Δn(λ)… (4)

(Wherein, Re(λ) represents an in-plane retardation value at a wavelength of λ nm, d represents a film thickness, and Δn(λ) represents a birefringence at a wavelength of λ nm.)

[Polymerizable liquid crystal compound for forming retardation layer]

A polymerizable liquid crystal compound is a liquid crystal compound which has a polymerizable functional group, especially a photopolymerizable functional group. The photopolymerizable functional group refers to a group capable of participating in a polymerization reaction by an active radical, an acid, or the like generated from a photopolymerization initiator. Examples of the photopolymerizable functional group include a vinyl group, a vinyloxy group, a 1-chlorovinyl group, an isopropenyl group, a 4-vinylphenyl group, an acryloyloxy group, a methacryloyloxy group, an oxiranyl group, and an oxetanyl group. can Among these, acryloyloxy group, methacryloyloxy group, vinyloxy group, oxiranyl group and oxetanyl group are preferable, and acryloyloxy group is more preferable. Although the liquid crystal may be a thermotropic liquid crystal or a lyotropic liquid crystal may be sufficient, a thermotropic liquid crystal is preferable at the point which precise|minute film thickness control is possible. In addition, as a normal-order structure in a thermotropic liquid crystal, a nematic phase structure may be sufficient, or a smectic phase structure may be sufficient.

In this invention, as a polymeric liquid crystal compound which forms retardation layer, the compound which has a structure of following formula (I) from a point which expresses the above-mentioned reverse wavelength dispersion property is especially preferable.

In formula (I), Ar represents a divalent aromatic group, and at least 1 or more of a nitrogen atom, an oxygen atom, and a sulfur atom is contained in this divalent aromatic group.

G ¹ and G ² each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group. Here, the hydrogen atom contained in the divalent aromatic group or the divalent alicyclic hydrocarbon group is a halogen atom, an alkyl group having 1 to 4 carbon atoms, a fluoroalkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group, or It may be substituted by the nitro group, and the carbon atom which comprises the divalent aromatic group or divalent alicyclic hydrocarbon group may be substituted by the oxygen atom, a sulfur atom, or a nitrogen atom.

L ¹ , L ² , B ¹ and B ² are each independently a single bond or a divalent linking group.

k and l each independently represent the integer of 0-3, and satisfy|fill the relationship of 1 ≤ k+1. Here, when 2 ≤ k+1, B ¹ and B ² , G ¹ and G ² may be the same as or different from each other, respectively.

E ¹ and E ² each independently represent an alkanediyl group having 1 to 17 carbon atoms, wherein the hydrogen atom contained in the alkanediyl group may be substituted with a halogen atom, and -CH ₂ contained in the alkanediyl group - may be substituted with -O- or -Si-.

P ¹ and P ² each independently represent a polymerizable group or a hydrogen atom, and at least one of them is a polymerizable group.

G ¹ and G ² are each independently, preferably a 1,4-phenyl group optionally substituted with at least one substituent selected from the group consisting of a halogen atom and an alkyl group having 1 to 4 carbon atoms, a halogen atom and 1 carbon atom. A 1,4-cyclohexyl group optionally substituted with at least one substituent selected from the group consisting of an alkyl group of 4, more preferably a 1,4-phenyl group substituted with a methyl group, an unsubstituted 1,4-phenyl group , or an unsubstituted 1,4-trans-cyclohexyl group, particularly preferably an unsubstituted 1,4-phenyl group or an unsubstituted 1,4-trans-cyclohexyl group.

In addition, at least one of the plurality of G ¹ and G ² is preferably a divalent alicyclic hydrocarbon group, and at least one of G ¹ and G ² bonded to L ¹ or L ² is a divalent alicyclic hydrocarbon group. It is more preferable that it is a group.

L ¹ and L ² are each independently, preferably, a single bond, -O-, -CH ₂ CH ₂ -, -CH ₂ O-, -COO-, -OCO-, -N=N-, -CR ^a =CR ^b -, or -C≡C-. Here, R ^a and R ^b represent an alkyl group having 1 to 4 carbon atoms or a hydrogen atom. L ¹ and L ² are each independently, more preferably a single bond, -O-, -CH ₂ CH ₂ -, -COO-, or -OCO-.

B ¹ and B ² are each independently, preferably, a single bond, -O-, -S-, -CH ₂ O-, -COO-, or -OCO-, More preferably, a single bond, - O-, -COO-, or -OCO-.

From the viewpoint of expression of reverse wavelength dispersion, k and l are preferably in the range of 2 ≤ k + l ≤ 6, preferably k + l = 4, and more preferably k = 2 and l = 2. If k = 2 and l = 2, it is preferable because it becomes a symmetric structure.

E ¹ and E ² are each independently preferably an alkanediyl group having 1 to 17 carbon atoms, and more preferably an alkanediyl group having 4 to 12 carbon atoms.

Examples of the polymerizable group represented by P ¹ or P ² include an epoxy group, a vinyl group, a vinyloxy group, a 1-chlorovinyl group, an isopropenyl group, a 4-vinylphenyl group, an acryloyloxy group, a methacryloyloxy group, and an oxiranyl group. , and an oxetanyl group.

Among these, acryloyloxy group, methacryloyloxy group, vinyloxy group, oxiranyl group and oxetanyl group are preferable, and acryloyloxy group is more preferable.

It is preferable that Ar has an aromatic heterocyclic ring. Examples of the aromatic heterocyclic ring include a furan ring, a benzofuran ring, a pyrrole ring, a thiophene ring, a pyridine ring, a thiazole ring, a benzothiazole ring, a thienothiazole ring, an oxazole ring, a benzoxazole ring, and phenantrol. Lean ring etc. are mentioned. Especially, it is preferable to have a thiazole ring, a benzothiazole ring, or a benzofuran ring, and it is more preferable to have a benzothiazole group.

Moreover, when a nitrogen atom is contained in Ar, it is preferable that this nitrogen atom has (pi) electron.

In formula (I), the total number of _pi electrons contained in the divalent aromatic group represented by Ar is preferably 10 or more, more preferably 14 or more, and still more preferably 18 or more. Moreover, Preferably it is 30 or less, More preferably, it is 26 or less, More preferably, it is 24 or less.

Examples of the aromatic group represented by Ar include the following groups.

In formulas (Ar-1) to (Ar-20), * represents a linking part, and Z ⁰ , Z ¹ and Z ² are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, and cya. No group, nitro group, C1-C12 alkylsulfinyl group, C1-C12 alkylsulfonyl group, carboxyl group, C1-C12 fluoroalkyl group, C1-C6 alkoxy group, C1-C12 alkylthio group , N-alkylamino group having 1 to 12 carbon atoms, N,N-dialkylamino group having 2 to 12 carbon atoms, N-alkylsulfamoyl group having 1 to 12 carbon atoms, or N,N-dialkylsulfamoyl group having 2 to 12 carbon atoms indicates

Q ¹ , Q ² and Q ³ each independently represent -CR ² 'R ³ '-, -S-, -NH-, -NR ² '-, -CO- or -O-, R ² ' and R ³ ′ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

Y ¹ , Y ² and Y ³ each independently represent an optionally substituted aromatic hydrocarbon group or an aromatic heterocyclic group.

W ¹ and W ² each independently represent a hydrogen atom, a cyano group, a methyl group or a halogen atom, and m represents an integer of 0-6.

Examples of the aromatic hydrocarbon group for Y ¹ , Y ² and Y ³ include aromatic hydrocarbon groups having 6 to 20 carbon atoms such as a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group and a biphenyl group, and a phenyl group and a naphthyl group preferred, and more preferably a phenyl group. Examples of the aromatic heterocyclic group include a nitrogen atom such as a furyl group, a pyrrolyl group, a thienyl group, a pyridinyl group, a thiazolyl group, and a benzothiazolyl group; The aromatic heterocyclic group of 20 is mentioned, A furyl group, a thienyl group, a pyridinyl group, a thiazolyl group, and a benzothiazolyl group are preferable.

Y ¹ , Y ² , and Y ³ may each independently represent an optionally substituted polycyclic aromatic hydrocarbon group or a polycyclic aromatic heterocyclic group. The polycyclic aromatic hydrocarbon group refers to a condensed polycyclic aromatic hydrocarbon group or a group derived from an aromatic ring set. The polycyclic aromatic heterocyclic group refers to a condensed polycyclic aromatic heterocyclic group or a group derived from an aromatic ring set.

Z ⁰ , Z ¹ and Z ² are each independently preferably a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a cyano group, a nitro group, or an alkoxy group having 1 to 12 carbon atoms, and Z ⁰ is a hydrogen atom , an alkyl group having 1 to 12 carbon atoms or a cyano group, and Z ¹ and Z ² are more preferably a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, or a cyano group.

As for Q ¹ , Q ² and Q ³ , -NH-, -S-, -NR ² '-, -O- are preferable, and R ² ' has a preferable hydrogen atom. Among these, -S-, -O-, and -NH- are especially preferable.

Among formulas (Ar-1) to (Ar-20), formulas (Ar-6) and (Ar-7) are preferred from the viewpoint of molecular stability.

In formulas (Ar-14) to (Ar-20), Y ¹ may form an aromatic heterocyclic group together with the nitrogen atom and Z ⁰ to which it is bonded. For example, a pyrrole ring, an imidazole ring, a pyrroline ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, an indole ring, a quinoline ring, an isoquinoline ring, a purine ring, a pyrrolidine ring, etc. are mentioned. This aromatic heterocyclic group may have a substituent. Further, Y ¹ together with the nitrogen atom and Z ⁰ to which it is bonded may be the polycyclic aromatic hydrocarbon group or polycyclic aromatic heterocyclic group which may be substituted as described above.

Content of the sum total of the polymeric liquid crystal compound which occupies in 100 mass parts of solid content of the said composition for retardation layer formation is 70 mass parts - 99.5 mass parts normally, Preferably they are 80 mass parts - 99 mass parts, More preferably Preferably it is 80 mass parts - 94 mass parts. When content of the said sum total is in the said range, there exists a tendency for the orientation of the retardation layer obtained to become high. Here, solid content means the total amount of the component except a solvent from a composition.

[Orientation layer B (alignment film for forming polarization layer)]

The elliptically polarizing plate of the present invention has an alignment layer B after the retardation layer. The orientation layer B is an orientation film for forming a polarizing layer.

It is preferable that the alignment layer B has solvent resistance that does not dissolve by application of the composition for forming a polarizing layer described later, etc., and has heat resistance in heat treatment for removal of the solvent or orientation of the polymerizable liquid crystal compound described later. do. Examples of the alignment film include a rubbing alignment film, a photo alignment film, and a groove alignment film having an uneven pattern or a plurality of grooves on the surface thereof. When applying to a long roll-like film, the photo-alignment film in which orientation control force is caused by polarized light irradiation is preferable at the point which can control an orientation direction easily.

Such an alignment film facilitates alignment of the polymerizable liquid crystal compound. In addition, various alignments such as horizontal alignment, hybrid alignment, and oblique alignment can be controlled according to the type of alignment layer, rubbing conditions, or light irradiation conditions.

The thickness of the orientation layer B is in the range of 80 to 800 nm (0.08 µm to 0.8 µm), preferably in the range of 100 to 500 nm (0.1 µm to 0.5 µm), more preferably 150 nm (0.15 µm). More than that. When the film thickness is smaller than this range, the optical axis of the polarizing layer next to the alignment layer B may deviate from a desired value due to the influence of a layer formed immediately below the alignment layer, that is, a retardation layer or the like. On the other hand, when a film thickness is larger than this range, an orientation regulating force may fall and an orientation defect may generate|occur|produce in a polarizing layer.

Examples of the alignment polymer used for the rubbing alignment layer include polyamides and gelatins having amide bonds, polyimides having imide bonds and hydrolyzates thereof, polyamic acid, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, and poly and acrylamide, polyoxazole, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid, and polyacrylic acid esters. Especially, polyvinyl alcohol is preferable. You may combine 2 or more types of orientation polymers.

The rubbing alignment film can impart an orientation regulating force by applying a composition in which an orientation polymer is dissolved in a solvent to a substrate, forming a coating film by removing the solvent, and rubbing the coating film in general.

The density|concentration of the orientation polymer in an orientation polymer composition should just be the range which an orientation polymer fully dissolves in a solvent. Content of the orientation polymer with respect to an orientation polymer composition becomes like this. Preferably it is 0.1-20 mass %, More preferably, it is 0.1-10 mass %.

The orientation polymer composition can be obtained from a market. As a commercially available orientation polymer composition, SunEver (trademark, manufactured by Nissan Chemical Industry Co., Ltd.), Optomer (trademark, manufactured by JSR Corporation), etc. are mentioned.

As a method of apply|coating an orientation polymer composition, the method similar to the method of apply|coating the composition for optically anisotropic layer formation mentioned later is mentioned. As a method of removing the solvent contained in an orientation polymer composition, the natural drying method, the ventilation drying method, heat drying, the reduced pressure drying method, etc. are mentioned.

As a method of a rubbing process, the method of making the said coating film contact with the rubbing roll which a rubbing cloth is wound up and is rotating is mentioned, for example. When performing a rubbing process, if masking is performed, a some area|region (pattern) from which an orientation direction differs can also be formed in an orientation film.

The photo-alignment film is usually obtained by applying a composition for forming a photo-alignment film comprising a polymer or monomer having a photoreactive group and a solvent on a substrate or the like, and irradiating polarized light (preferably polarized UV) after removing the solvent. . The photo-alignment film can control the direction of an orientation regulating force arbitrarily by selecting the polarization direction of the polarized light to irradiate.

A photoreactive group means group which raise|generates orientation ability by light irradiation. Specific examples include groups involved in photoreactions that are the origin of orientation ability, such as an orientation-inducing reaction of molecules generated by light irradiation, an isomerization reaction, a photodimerization reaction, a photocrosslinking reaction, or a photolysis reaction. The photoreactive group is preferably a group having an unsaturated bond, particularly a double bond, a carbon-carbon double bond (C=C bond), a carbon-nitrogen double bond (C=N bond), a nitrogen-nitrogen double bond (N=N A group having at least one selected from the group consisting of a bond) and a carbon-oxygen double bond (C=O bond) is particularly preferred.

Examples of the photoreactive group having a C=C bond include a vinyl group, a polyene group, a stilbene group, a stilbazole group, a stilbazolium group, a chalcone group, and a cinnamoyl group. Examples of the photoreactive group having a C=N bond include a group having a structure such as an aromatic Schiff base and an 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 bisazo group, a formazan group, and a group having an azoxybenzene 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 a substituent such as an alkyl group, an alkoxy group, an aryl group, an allyloxy group, a cyano group, an alkoxycarbonyl group, a hydroxyl group, a sulfonic acid group, or a halogenated alkyl group.

A group which participates in a photodimerization reaction or a photocrosslinking reaction is preferable at the point excellent in orientation. Among them, a photoreactive group involved in the photodimerization reaction is preferable, the amount of polarized light irradiation required for alignment is relatively small, and a photo-alignment film excellent in thermal stability and temporal stability is easily obtained, so cinnamoyl group and chalcone group group is preferred. As a polymer which has a photoreactive group, it is especially preferable that the terminal part of the said polymer side chain has a cinnamoyl group which becomes a cinnamic acid structure or a cinnamic acid ester structure.

Content of the polymer or monomer which has a photoreactive group in the composition for photo-alignment film formation can be adjusted according to the kind of polymer or monomer, or the thickness of the photo-alignment film made into the objective, It is preferable to set it as at least 0.2 mass % or more, 0.3-10 The range of mass % is more preferable.

As a method of apply|coating the composition for photo-alignment film formation, the method similar to the method of apply|coating the composition for optically anisotropic layer formation mentioned later is mentioned. As a method of removing a solvent from the apply|coated composition for photo-alignment film formation, the method similar to the method of removing a solvent from an orientation polymer composition is mentioned.

In order to irradiate polarized light, from the composition for forming a photo-alignment film applied on a substrate, etc., the solvent may be directly irradiated with polarized light, or polarized light is irradiated from the side of the substrate to be applied, and polarized light is transmitted and irradiated. It may be in the form Moreover, it is preferable that the said polarization|polarized-light is substantially parallel light. The wavelength of the polarized light to be irradiated is preferably in a wavelength range in which the photoreactive group of the polymer or monomer having a photoreactive group can absorb light energy. Specifically, UV (ultraviolet rays) having a wavelength of 250 nm to 400 nm is particularly preferable. Examples of the light source for irradiating the polarized light include a xenon lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, and an ultraviolet laser such as KrF and ArF. Especially, since the high-pressure mercury-vapor lamp, the ultra-high pressure mercury lamp, and the metal halide lamp have the large luminous intensity of the ultraviolet-ray of wavelength 313nm, it is preferable.

Polarized UV can be irradiated by irradiating the light from the said light source through a suitable polarizing element. Examples of the polarizing element include a polarizing filter, a polarizing prism such as Glan Thompson and Glan Taylor, and a wire grid. Among them, a wire grid type polarizing element is preferable from the viewpoint of increasing the area and resistance to heat.

Moreover, when performing rubbing or polarized light irradiation and masking, the some area|region (pattern) from which the direction of a liquid-crystal orientation differs can also be formed.

A groove alignment film is a film|membrane which has an uneven|corrugated pattern or a plurality of grooves (grooves) on the film surface. When a polymerizable liquid crystal compound is applied to a film having a plurality of straight grooves arranged at equal intervals, the liquid crystal molecules are aligned in a direction along the grooves.

As a method of obtaining a groove alignment film, a method of forming an uneven pattern by developing and rinsing after exposure through an exposure mask having a pattern-shaped slit on the surface of the photosensitive polyimide film, a method of forming an uneven pattern on the surface A method of forming a layer of UV-curing resin before curing, transferring the resin layer to a substrate, etc., and then curing, and a roll-shaped disk having a plurality of grooves in a film of UV-curing resin before curing formed on a substrate, etc. The method of forming unevenness|corrugation by pressurization, and hardening after that, etc. are mentioned.

[Polarization layer]

The elliptically polarizing plate of the present invention has a polarizing layer after the alignment layer B. This polarizing layer is formed by coating a composition containing a polymerizable liquid crystal compound (hereinafter also referred to as “a composition for forming a polarizing layer”) on the alignment layer B, and in a state in which the dichroic dye and the polymerizable liquid crystal compound are aligned. It can be produced by forming a polarizing layer which consists of a polymer of a polymeric liquid crystal compound of That is, when light is anisotropically absorbed by the dichroic dye subsumed in the liquid crystal compound, it becomes a polarizing plate that absorbs a linearly polarized light component having an oscillation plane parallel to the absorption axis and transmits a linearly polarized light component having an orthogonal oscillation plane. Such a polarizing plate is preferable at the point which can control a color arbitrarily by a dichroic dye, and the point which can reduce thickness. In addition, the composition for forming a polarizing layer may further contain a solvent, a photoinitiator, a photosensitizer, a polymerization inhibitor, a leveling agent, an adhesion improving agent, and the like.

The polarizing layer in the elliptically polarizing plate of the present invention is usually obtained by applying a composition for forming a polarizing layer on an alignment layer B formed on a transparent substrate or the like, and adding a polymerizable liquid crystal compound contained in the composition for forming a polarizing layer. It is formed by polymerization. A polarizing layer is a film|membrane with a thickness of 5 micrometers or less which hardened|cured normally in the state which the polymeric liquid crystal compound oriented, Preferably it is 4 micrometers or less, More preferably, it is 3 micrometers or less. When a film thickness becomes thicker than this range, the orientation regulating force by an orientation film will fall and there exists a tendency for an orientation defect to arise easily.

In the case of obtaining the polarization property in the X-Y plane, the polymerizable liquid crystal compound may be cured in a state in which the dichroic dye and the polymerizable liquid crystal compound are horizontally aligned with respect to the transparent substrate surface, and in the Z direction (the film thickness direction of the polarizing layer) What is necessary is just to harden a polymeric liquid crystal compound in the state in which a dichroic dye and a polymeric liquid crystal compound are vertically oriented with respect to the transparent base material surface, when obtaining the polarization characteristic. At this time, from the viewpoint of selectivity of polarization absorption, it is preferably a liquid crystal cured film in which the polymerizable liquid crystal compound is cured to a smectic liquid crystal phase, and more preferably a liquid crystal cured film cured to a high-order smectic liquid crystal phase. The higher-order smectic liquid crystal phase as used herein refers to the smectic B phase, the smectic D phase, the smectic E phase, the smectic F phase, the smectic G phase, the smectic H phase, the smectic I phase, the smectic J phase, and the smectic phase. It is a smectic K phase and a smectic L phase, and Smectic B phase, a smectic F phase, and a smectic I phase are more preferable especially.

If it is these higher-order smectic liquid crystal phases, a polarizing layer with a higher degree of orientation order can be manufactured. In addition, in the polarizing layer prepared from the high-order smectic liquid crystal phase having a high degree of alignment order in this way, a Bragg peak derived from a higher-order structure such as a hexatic phase or a crystal phase is obtained in X-ray diffraction measurement. The said Bragg peak is a peak derived from the surface periodic structure of molecular orientation, and according to the composition for polarizing layer formation which concerns on this embodiment, a polarizing layer with a periodic interval of 3.0-5.0 Angstrom can be obtained.

Whether the polymerizable liquid crystal compound exhibits a nematic liquid crystal phase or a smectic liquid crystal phase can be confirmed, for example, as follows. After forming a coating film by apply|coating the composition for polarizing layer formation to a base material, the solvent contained in a coating film is removed by heat-processing under the conditions which a polymeric liquid crystal compound does not superpose|polymerize. Then, the liquid crystal phase developed by heating the coating film formed on the base material to an isotropic temperature and cooling it gradually is inspected by texture observation with a polarizing microscope, X-ray diffraction measurement, or differential scanning calorimetry. In the nematic liquid crystal phase and the smectic liquid crystal phase, that the polymerizable liquid crystal compound and the dichroic dye are not phase-separated can be confirmed by, for example, surface observation with various microscopes or measurement of scattering with a haze meter. have.

The optically anisotropic layer obtained by curing the polymerizable liquid crystal compound in a state in which the dichroic dye and the polymerizable liquid crystal compound are horizontally aligned with respect to the surface of the transparent substrate has a liquid crystal alignment horizontal absorbance A1 (λ) and liquid crystal with respect to light having a wavelength of λ nm The ratio (dichroic ratio) of the absorbance A2(λ) in the direction perpendicular to the orientation is preferably 7 or more, more preferably 20 or more, still more preferably 30 or more. It is a polarizing plate excellent in absorption selectivity, so that this value is high. Although it changes with the kind of a dichroic dye, in the case of the liquid crystal cured film hardened|cured in the state of a nematic liquid crystal phase, it is about 5-10.

By mixing two or more types of dichroic dyes having different absorption wavelengths, a polarizing layer of various colors can be produced, and a polarizing layer having absorption over the entire visible light can be obtained. By setting it as a polarizing layer which has such an absorption characteristic, blackening can be carried out and it can expand|deploy to various uses. The polarization performance of a polarizing layer can be measured using a spectrophotometer. For example, the transmittance (T1) in the transmission axis direction (orthogonal direction) and transmittance (T2) in the absorption axis direction (same direction) in the wavelength range of 380 nm to 780 nm, which is visible light, is measured by a polarizer attached to the spectrophotometer. Measurements can be made by the double beam method using an apparatus with a set folder. The polarization performance in the visible light range uses the following formulas (Formula 1) and (Formula 2) to calculate the single transmittance and polarization degree at each wavelength, and further to the 2 degree field of view (C light source) of JIS Z 8701. By performing a visibility correction|amendment by this, it is computable by the visibility correction|amendment single transmittance (Ty) and the visibility correction|amendment polarization degree (Py). In addition, by calculating the chromaticity a* and b* in the L*a*b* (CIE) color system from the transmittance measured in the same manner, using the color matching function of the C light source, the hue of the polarizing plate alone (single color), the polarizing plate A hue (parallel hue) and a hue (orthogonal hue) in which polarizing plates are orthogonally disposed are obtained.

As the values of a* and b* are closer to 0, it may be determined that the colors are neutral.

Single transmittance (%) = (T1 + T2)/2... (Formula 1)

Polarization degree (%) = (T1 - T2) / (T1 + T2) × 100 ... (Formula 2)

[Polymerizable liquid crystal compound for polarizing layer formation]

A polymerizable liquid crystal compound is a compound which has a polymeric group and has liquid crystallinity. A polymerizable group means group which participates in a polymerization reaction, and it is preferable that it is a photopolymerizable group. Here, the photopolymerizable group refers to a group capable of participating in a polymerization reaction by an active radical, an acid, or the like generated from a photopolymerization initiator described later. Examples of the polymerizable group include a vinyl group, a vinyloxy group, a 1-chlorovinyl group, an isopropenyl group, a 4-vinylphenyl group, an acryloyloxy group, a methacryloyloxy group, an oxiranyl group, and an oxetanyl group. . Among these, acryloyloxy group, methacryloyloxy group, vinyloxy group, oxiranyl group and oxetanyl group are preferable, and acryloyloxy group is more preferable. A thermotropic liquid crystal may be sufficient as a liquid crystal, or a lyotropic liquid crystal may be sufficient as it, However, When mixing with the dichroic dye mentioned later, a thermotropic liquid crystal is preferable.

When the polymerizable liquid crystal compound is a thermotropic liquid crystal, it may be a thermotropic liquid crystal compound exhibiting a nematic liquid crystal phase or a thermotropic liquid crystal compound exhibiting a smectic liquid crystal phase. In the present invention, the polymerizable liquid crystal compound is preferably a smectic liquid crystal compound, more preferably a higher order smectic liquid crystal compound, from the viewpoint of obtaining higher polarization properties. Among them, smectic B phase, smectic D phase, smectic E phase, smectic F phase, smectic G phase, smectic H phase, smectic I phase, smectic J phase, smectic K phase or smectic phase A higher-order smectic liquid crystal compound forming an L phase is more preferable, and a higher-order smectic liquid crystal compound forming a smectic B phase, a smectic F phase or a smectic I phase is still more preferable. If the liquid crystal phases formed by the polymerizable liquid crystal compound are these higher-order smectic phases, a polarizing layer having higher polarization performance can be produced. Moreover, in X-ray diffraction measurement, the Bragg peak derived from a higher order structure, such as a hexatic phase and a crystal phase, is obtained in the polarizing layer with such high polarization performance. The Bragg peak is a peak derived from the periodic structure of molecular orientation, and a film having a periodic interval of 3 to 6 angstroms can be obtained. The polarizing layer used in the present invention preferably contains a polymer of a polymerizable liquid crystal compound in which the polymerizable liquid crystal compound is polymerized in a smectic phase from the viewpoint of obtaining higher polarization properties.

Specific examples of such a compound include a compound represented by the following formula (A) (hereinafter sometimes referred to as a compound (A)) and the like. The said polymerizable liquid crystal compound may be used independently and may be used in combination of 2 or more type.

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

[In formula (A),

X ¹ , X ² and X ³ each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group, wherein the hydrogen atom contained in the divalent aromatic group or divalent alicyclic hydrocarbon group is a halogen atom, The carbon atoms constituting the divalent aromatic group or divalent alicyclic hydrocarbon group may be substituted with an alkyl group having 1 to 4 carbon atoms, a fluoroalkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group or a nitro group. , an oxygen atom, a sulfur atom, or a nitrogen atom may be substituted. However, at least one of X ¹ , X ² and X ³ is a 1,4-phenylene group which may have a substituent or a cyclohexane-1,4-diyl group which may have a substituent.

Y ¹ , Y ² , W ¹ and W ² are each independently a single bond or a divalent linking group.

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

U ¹ and U ² each independently represent a polymerizable group or a hydrogen atom, and at least one of them is a polymerizable group.

In the compound (A), at least one of X ¹ , X ² and X ³ is a 1,4-phenylene group which may have a substituent or a cyclohexane-1,4-diyl group which may have a substituent. it is preferable In particular, X ¹ and X ³ are more preferably a cyclohexane-1,4-diyl group which may have a substituent, and the cyclohexane-1,4-diyl group is trans-cyclohexane-1,4-diyl group. It is more preferable that it is a diary. When the structure of the trans-cyclohexane-1,4-diyl group is included, smectic liquid crystallinity tends to be easily expressed. Moreover, as a substituent which the 1, 4- phenylene group which may have a substituent, or the cyclohexane-1, 4- diyl group which may have a substituent optionally has, C1-C4, such as a methyl group, an ethyl group, and a butyl group Although an alkyl group, a cyano group, and halogen atoms, such as a chlorine atom and a fluorine atom, are mentioned, Preferably it is unsubstituted.

Y ¹ and Y ² are, independently of each other, a single bond, -CH ₂ CH ₂ -, -CH ₂ O-, -COO-, -OCO-, -N=N-, -CR ^a =CR ^b -, - C≡C- or CR ^a =N- is preferable, and R ^a and R ^b each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Y ¹ and Y ² are more preferably -CH ₂ CH ₂ -, -COO-, -OCO-, or a single bond, and more preferably Y ¹ and Y ² are different from each other. When Y1 and Y2 differ from ^each other, there exists ^a tendency for smectic liquid crystal to express easily.

W ¹ and W ² are each independently preferably a single bond, -O-, -S-, -COO- or OCO-, and more preferably a single bond or -O- independently of each other.

Examples of the alkanediyl group having 1 to 20 carbon atoms represented by V ¹ and V ² include a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,3-diyl group, and a 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, decane-1,10-diyl group, tetradecane-1 , 14-diyl group and icosane-1,20-diyl group, and the like. V ¹ and V ² are preferably an alkanediyl group having 2 to 12 carbon atoms, and more preferably a linear alkanediyl group having 6 to 12 carbon atoms. By setting it as a linear C6-C12 alkanediyl group, crystallinity improves and there exists a tendency for smectic liquid crystalline property to be easily expressed.

Examples of the substituent optionally included in the alkanediyl group having 1 to 20 carbon atoms which may have a substituent include a cyano group and a halogen atom such as a chlorine atom and a fluorine atom, but the alkanediyl group is preferably unsubstituted, It is more preferable that it is an unsubstituted and linear alkanediyl group.

Both U ¹ and U ² are preferably a polymerizable group, and both are more preferably a photopolymerizable group. The polymerizable liquid crystal compound having a photopolymerizable group is advantageous because it can polymerize under a lower temperature condition than that of the thermally polymerizable group, so that the liquid crystal can form a polymer in a state with a higher degree of order.

^Although the polymeric groups represented by ^U1 and U2 may mutually differ, the same thing is preferable. Examples of the polymerizable group include a vinyl group, a vinyloxy group, a 1-chlorovinyl group, an isopropenyl group, a 4-vinylphenyl group, an acryloyloxy group, a methacryloyloxy group, an oxiranyl group, and an oxetanyl group. . Among these, acryloyloxy group, methacryloyloxy group, vinyloxy group, oxiranyl group and oxetanyl group are preferable, and methacryloyloxy group or acryloyloxy group is more preferable.

As such a polymerizable liquid crystal compound, the following are mentioned, for example.

Among the exemplified compounds, formula (1-2), formula (1-3), formula (1-4), formula (1-6), formula (1-7), formula (1-8), formula ( 1-13), at least 1 sort(s) selected from the group which consists of a compound represented by Formula (1-14), and Formula (1-15) is preferable.

The illustrated compound (A) can be used for a polarizing layer individually or in combination. Moreover, when combining 2 or more types of polymerizable liquid crystal compounds, it is preferable that at least 1 type is a compound (A), and it is more preferable that 2 or more types are a compound (A). By combining two or more types of polymerizable liquid crystal compounds, liquid crystallinity can be temporarily maintained even at a temperature below the liquid crystal-crystal phase transition temperature in some cases. As a mixing ratio in the case of combining two types of polymeric liquid crystal compounds, it is 1:99-50:50 normally, Preferably it is 5:95-50:50, More preferably, it is 10:90-50: 50 is

Compound (A) is described, for example, in Lub et al. Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996), or a known method described in Japanese Patent No. 4719156 or the like.

The content rate of the polymerizable liquid crystal compound in the composition for polarizing layer formation is 50-99.5 mass parts normally with respect to 100 mass parts of solid content of the composition for polarizing layer formation, Preferably it is 60-99 mass parts, More Preferably it is 70-98 mass parts, More preferably, it is 80-97 mass parts. When the content ratio of the polymerizable liquid crystal compound is within the above range, the orientation tends to increase. Here, solid content means the total amount of the component except a solvent from the composition for polarizing layer formation.

[Dichromatic Dye for Polarizing Layer Formation]

A dichroic dye means a dye which has the property from which the absorbance in the long-axis direction of a molecule|numerator differs from the absorbance in a short-axis direction. As a dichroic dye, it is preferable to have a characteristic which absorbs visible light, and it is more preferable to have an absorption maximum wavelength ((lambda)MAX) in the range of 380-680 nm. As such a dichroic dye, although an acridine dye, an oxazine dye, a cyanine dye, a naphthalene dye, an azo dye, an anthraquinone dye, etc. are mentioned, for example, Among these, an azo dye is preferable. As an azo dye, a monoazo dye, a bisazo dye, a trisazo dye, a tetrakis azo dye, a stilbenazo dye, etc. are mentioned, Preferably they are a bisazo dye and a trisazo dye. Although individual dichroic dyes may be used or they may be combined, in order to obtain absorption in visible light whole, it is preferable to combine three or more types of dichroic dyes, and it is more preferable to combine three or more types of azo dyes.

As an azo dye, the compound (Hereinafter, it may be called "compound (B)") represented by Formula (B) is mentioned, for example.

T ¹ -A ¹ (-N=NA ² ) _p -N=NA ³ -T ² (B)

[In formula (B),

A ¹ and A ² and A ³ each independently represent a 1,4-phenylene group which may have a substituent, a naphthalene-1,4-diyl group or a divalent heterocyclic group which may have a substituent, A ¹ or / and A ² is a 1,4-phenylene group, T ¹ and T ² are an electron withdrawing group or an electron emitter, and have a position substantially 180° with respect to the azo bonding plane. p represents the integer of 0-4. When p is 2, two A ² may be mutually identical or different.]

Examples of the substituent optionally included in the 1,4-phenylene group, the naphthalene-1,4-diyl group and the divalent heterocyclic group in A ¹ and A ² and A ³ include a methyl group, an ethyl group, and a butyl group having 1 to 4 carbon atoms. an alkyl group of ; C1-C4 alkoxy groups, such as a methoxy group, an ethoxy group, and a butoxy group; a C1-C4 fluorinated alkyl group, such as a trifluoromethyl group; cyano group; nitro group; Halogen atoms, such as a chlorine atom and a fluorine atom; A substituted or unsubstituted amino group such as an amino group, a diethylamino group or a pyrrolidino group (a substituted amino group is an amino group having one or two C1-C6 alkyl groups, or two substituted alkyl groups having 2 to 8 carbon atoms bonded to each other means an amino group forming an alkanediyl group of . The unsubstituted amino group is -NH ₂ ). Moreover, as a C1-C6 alkyl group, a methyl group, an ethyl group, a hexyl group, etc. are mentioned. Examples of the alkanediyl group having 2 to 8 carbon atoms include ethylene group, propane-1,3-diyl group, butane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, A hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, etc. are mentioned. In order to be included in a high-order liquid crystal structure such as a smectic liquid crystal, A ¹ and A ² and A ³ are preferably an unsubstituted or 1,4-phenylene group in which hydrogen is substituted with a methyl group or a methoxy group, or a divalent heterocyclic group, , p is preferably 0 or 1. Among them, it is more preferable that p is 1, and that at least two of the three structures of A ¹ and A ² and A ³ are 1,4-phenylene groups in terms of both simplicity of molecular synthesis and high performance. .

Examples of the divalent heterocyclic group include groups in which two hydrogen atoms have been removed from quinoline, thiazole, benzothiazole, thienothiazole, imidazole, benzimidazole, oxazole and benzoxazole. When A ² is a divalent heterocyclic group, a structure in which the molecular bond angle is substantially 180° is preferable, and specifically, a benzothiazole, benzoimidazole, or benzoxazole structure in which two 5-membered rings are condensed is more preferable.

T ¹ and T ² are an electron withdrawing group or an electron emitter, and preferably have different structures, more preferably T ¹ is an electron withdrawing group and T ² is an electron emitter, or T ¹ is an electron emitter and T ² is an electron withdrawing group do. Specifically, T ¹ and T ² are each independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group, a nitro group, an amino group having one or two alkyl groups having 1 to 6 carbon atoms, or An amino group or trifluoromethyl group in which two substituted alkyl groups are bonded to each other to form an alkanediyl group having 2 to 8 carbon atoms is preferable. Since the structure needs to be smaller in volume, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group, an amino group having one or two alkyl groups having 1 to 6 carbon atoms, or two substituted alkyl groups Amino groups which combine with each other to form an alkanediyl group having 2 to 8 carbon atoms are preferable.

As such an azo dye, the following are mentioned, for example.

In formulas (2-1) to (2-6),

B ¹ to B ²⁰ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group, a nitro group, a substituted or unsubstituted amino group (Definition of a substituted amino group and an unsubstituted amino group) represents the same as above), a chlorine atom or a trifluoromethyl group.

n1-n4 respectively independently represent the integer of 0-3.

When n1 is 2 or more, a plurality of B ² may be the same or different, respectively,

When n2 is 2 or more, a plurality of B ⁶ may be the same or different, respectively,

When n3 is 2 or more, a plurality of B ⁹ may be the same or different, respectively,

When n4 is 2 or more, some B ¹⁴ may be respectively same or different.

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

[In formula (2-7),

R ¹ to R ⁸ each independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom.

R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms.]

As said oxazine dye, the compound represented by Formula (2-8) is preferable.

[In formula (2-8),

R ⁹ to R ¹⁵ each independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom.

R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms.]

As said acridine dye, the compound represented by Formula (2-9) is preferable.

[In formula (2-9),

R ¹⁶ to R ²³ each independently represent a hydrogen atom, -R ^x , -NH ₂ , -NHR ^x , -NR ^x ₂ , -SR ^x or a halogen atom.

R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms.]

Examples of the alkyl group having 1 to 4 carbon atoms represented by R ^x in the formulas (2-7), (2-8) and (2-9) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group and A hexyl group etc. are mentioned, A phenyl group, a toluyl group, a xylyl group, a naphthyl group, etc. are mentioned as a C6-C12 aryl group.

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

[In formula (2-10),

D ¹ and D ² each independently represent a group represented by any of the formulas (2-10a) to (2-10d).

n5 represents an integer of 1 to 3.]

[In formula (2-11),

D ³ and D ⁴ each independently represent a group represented by any of the formulas (2-11a) to (2-11h).

n6 represents an integer of 1 to 3.]

Content (the total amount when multiple types are included) of a dichroic dye is 1-30 mass parts normally with respect to 100 mass parts of polymeric liquid crystal compounds from a viewpoint of obtaining favorable light absorption characteristics, Preferably it is 2 - It is 20 mass parts, More preferably, it is 3-15 mass parts. When content of a dichroic dye is less than this range, light absorption becomes inadequate, sufficient polarization|polarized-light performance is not acquired, but when more than this range, the orientation of a liquid crystal molecule may be inhibited.

[Angle between the polarizing layer and the retardation layer]

In the elliptically polarizing plate of the present invention, the optical axes of the polarizing layer and the retardation layer are in a substantially parallel relationship, that is, the optical axis of the polarizing layer and the optical axis of the retardation layer are not substantially intersecting within the plane of the elliptically polarizing plate. The optical axis of the polarizing layer and the optical axis of the retardation layer intersect within the plane. The angle between the optical axis of the polarizing layer that intersects with each other and the optical axis of the retardation layer is an angle between the slow axis of the retardation layer and the absorption axis of the polarizing layer, preferably 40 to 50°, more preferably 41 to 49°, , more preferably 43 to 47°, particularly preferably substantially 45°, and ideally 45°. When the angle between the retardation layer slow axis and the absorption axis of the polarizing layer is within the above range, the ellipticity is improved, and in particular, when the angle is 45°, the polarizing plate of the present invention substantially functions as a circular polarizing plate.

[solvent]

As the solvent, a solvent capable of completely dissolving the polymerizable liquid crystal compound used in forming the retardation layer or the polarizing layer described above is preferable, and a solvent that is inactive to the polymerization reaction of the polymerizable liquid crystal compound is preferable.

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, 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; chlorine-containing solvents such as chloroform and chlorobenzene; and amide solvents such as dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone, and 1,3-dimethyl-2-imidazolidinone. Only one type may be used for these solvents, and may be used combining two or more types. Among them, an alcohol solvent, an ester solvent, a ketone solvent, a chlorine-containing solvent, an amide solvent, and an aromatic hydrocarbon solvent are preferable.

50 mass parts - 98 mass parts are preferable, and, as for content of the solvent which occupies for 100 mass parts of compositions, 70 weight part - 95 weight part are more preferable. Therefore, as for the solid content which occupies for 100 mass parts of compositions, 2 mass parts - 50 mass parts are preferable. When the solid content of the composition is 50 parts by mass or less, since the viscosity of the composition is lowered, the thickness of the film containing the polymerizable liquid crystal compound becomes substantially uniform, and unevenness is less likely to occur in the film containing the polymerizable liquid crystal compound. There is this. The solid content can be appropriately determined in consideration of the thickness of the film containing the polymerizable liquid crystal compound to be produced.

[Photoinitiator]

The polymerization initiator is a compound capable of initiating a polymerization reaction such as a polymerizable liquid crystal compound. As a polymerization initiator, the photoinitiator which generate|occur|produces a radical by light irradiation is more preferable.

Examples of the photopolymerization initiator include a benzoin compound, a benzophenone compound, a benzyl ketal compound, an α-hydroxyketone compound, an α-aminoketone compound, a triazine compound, an iodonium salt, and a sulfonium salt. Specifically, Irgacure (registered trademark) 907, Irgacure 184, Irgacure 651, Irgacure 819, Irgacure 250, Irgacure 369, Irgacure 379, Irgacure 127, Irgacure 2959, Irgacure 754, Irgacure 379EG (above, manufactured by BASF Japan Co., Ltd.), Sakeol BZ, Sakeol Z, Sakeol BEE (above, manufactured by Seiko Chemical Co., Ltd.), Kayacure BP100 ( Nippon Kayaku Co., Ltd.), Kayacure UVI-6992 (manufactured by Dow Corporation), Adeka Optomer SP-152, Adeka Optomer SP-170, Adeka Optomer N-1717, Adeka Optomer N-1919, Adeka Optomer N-1919 Deca Accruz NCI-831, Adeca Accruz NCI-930 (above, manufactured by ADEKA Co., Ltd.), TAZ-A, TAZ-PP (above, manufactured by Nippon Syber Heigner) and TAZ-104 (manufactured by Sanwa Chemical) can be heard

The composition for retardation layer formation or the composition for polarizing layer formation WHEREIN: The photoinitiator contained is at least 1 type, and it is preferable that it is 1 type or 2 types.

Since the photoinitiator can fully utilize the energy generated from a light source and is excellent in productivity, it is preferable that the maximum absorption wavelength is 300 nm - 380 nm, It is more preferable that it is 300 nm - 360 nm, Among them, An α-acetophenone-based polymerization initiator and an oxime-based photopolymerization initiator are preferable.

Examples of the α-acetophenone compound include 2-methyl-2-morpholino-1-(4-methylsulfanylphenyl)propan-1-one, 2-dimethylamino-1-(4-morpholinophenyl)- 2-benzylbutan-1-one and 2-dimethylamino-1-(4-morpholinophenyl)-2-(4-methylphenylmethyl)butan-1-one, and more preferably 2- methyl-2-morpholino-1-(4-methylsulfanylphenyl)propan-1-one and 2-dimethylamino-1-(4-morpholinophenyl)-2-benzylbutan-1-one can be heard As a commercial item of (alpha)-acetophenone compound, Irgacure 369, 379EG, 907 (above, BASF Japan Co., Ltd. make), Sikol BEE (made by Seiko Chemicals), etc. are mentioned.

An oxime-type photoinitiator produces|generates a methyl radical by irradiating light. The polymerization of the polymerizable liquid crystal compound in the deep portion of the film containing the polymerizable liquid crystal compound proceeds favorably by this methyl radical. Moreover, it is preferable to use the photoinitiator which can utilize the ultraviolet-ray with a wavelength of 350 nm or more efficiently from a viewpoint of advancing the polymerization reaction in the deep part of the film|membrane containing a polymeric liquid crystal compound more efficiently. As a photoinitiator which can utilize the ultraviolet-ray of wavelength 350nm or more efficiently, a triazine compound and an oxime ester type carbazole compound are preferable, and an oxime ester type carbazole compound is more preferable from a viewpoint of a sensitivity. Examples of the oxime ester-type carbazole compound include 1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyloxime)], ethanone, 1-[9-ethyl-6-(2) -Methylbenzoyl)-9H-carbazol-3-yl]-1-(O-acetyloxime), etc. are mentioned. As a commercial item of an oxime ester type carbazole compound, Irgacure OXE-01, Irgacure OXE-02, Irgacure OXE-03 (above, BASF Japan Co., Ltd. make), Adeca Optomer N-1919, Adeka Accruz NCI-831 (above, manufactured by ADEKA Corporation) etc. are mentioned.

The addition amount of a photoinitiator is 0.1 mass part - 30 mass parts normally with respect to 100 mass parts of polymeric liquid crystal compounds, Preferably they are 1 mass part - 20 mass parts, More preferably, they are 3 mass parts - 18 mass parts is the mass part. If it is in the said range, reaction of a polymeric group fully advances, and the orientation of a polymeric liquid crystal compound is hard to be disturbed.

By mix|blending a polymerization inhibitor, the polymerization reaction of a polymerizable liquid crystal compound is controllable. Examples of the polymerization inhibitor include hydroquinones having a substituent such as hydroquinone and alkyl ether; catechols having a substituent such as an alkyl ether such as butyl catechol; radical scavengers such as pyrogallols and 2,2,6,6-tetramethyl-1-piperidinyloxy radicals; thiophenols; β-naphthylamines and β-naphthols are mentioned. Content of a polymerization inhibitor is 0.1-10 mass parts normally with respect to 100 mass parts of polymeric liquid crystal compounds in order to superpose|polymerize a polymeric liquid crystal compound without disturbing the orientation of a polymeric liquid crystal compound, Preferably it is 0.5 - 5 mass parts, More preferably, it is 0.5-3 mass parts.

Moreover, a photoinitiator can be made highly sensitive by using a photosensitizer. As a photosensitizer, For example, xanthone, such as a xanthone and a thioxanthone; anthracenes having a substituent such as anthracene and alkyl ether; phenothiazine; Rubrene can be mentioned. As a photosensitizer, For example, xanthone, such as a xanthone and a thioxanthone; anthracenes having a substituent such as anthracene and alkyl ether; phenothiazine; Rubrene can be mentioned. Content of a photosensitizer is 0.1-10 mass parts normally with respect to 100 mass parts of polymeric liquid crystal compounds, Preferably it is 0.5-5 mass parts, More preferably, it is 0.5-3 mass parts.

[Leveling agent]

A leveling agent is an additive which has the function of adjusting the fluidity|liquidity of a composition and making the film|membrane obtained by apply|coating a composition more flat, For example, organic-modified silicone oil type, polyacrylate type, and a perfluoroalkyl type|system|group leveling agent. can be heard Specifically, DC3PA, SH7PA, DC11PA, SH28PA, SH29PA, SH30PA, ST80PA, ST86PA, SH8400, SH8700, FZ2123 (above, all manufactured by Toray Dow Corning Co., Ltd.), KP321, KP323, KP324, KP326, KP340, KP341, X22-161A, KF6001 (above, all manufactured by Shin-Etsu Chemical Co., Ltd.), TSF400, TSF401, TSF410, TSF4300, TSF4440, TSF4445, TSF-4446, TSF4452, TSF4460 (above, all Momentive Performance Materials Japan) (manufactured by a joint venture company), fluorinert (registered trademark) FC-72, copper FC-40, copper FC-43, copper FC-3283 (above, all manufactured by Sumitomo 3M Co., Ltd.), Megapac (registered trademark) ) R-08, East R-30, East R-90, East F-410, East F-411, East F-443, East F-445, East F-470, East F-477, East F-479, East F-482, East F-483 (above, all manufactured by DIC Co., Ltd.), F-top (brand name) EF301, copper EF303, copper EF351, copper EF352 (above, all manufactured by Mitsubishi Material Electronics Co., Ltd.), Suplon (registered trademark) S-381, Dong S-382, Dong S-383, Dong S-393, Dong SC-101, Dong SC-105, KH-40, SA-100 (above, all are AGC Semi Chemical) (manufactured by Co., Ltd.), trade names E1830, copper E5844 (manufactured by Daikin Fine Chemical Research Institute), BM-1000, BM-1100, BYK-352, BYK-353 and BYK-361N (all trade names: manufactured by BM Chemie) ) and the like. Especially, a polyacrylate type leveling agent and a perfluoroalkyl type leveling agent are preferable.

As for content of the leveling agent in the composition for phase difference layer formation used for this invention, and the composition for polarizing layer formation, 0.01 mass part - 5 mass parts are preferable with respect to 100 mass parts of polymeric liquid crystal compounds, 0.1 mass part - 3 parts by mass is more preferable. It is easy to horizontally align a polymeric liquid crystal compound as content of a leveling agent is in the said range, and since there exists a tendency for the film|membrane containing the polymeric liquid crystal compound obtained to become smoother, it is preferable. The composition for phase difference layer formation and the composition for polarizing layer formation used for this invention may contain 2 or more types of leveling agents.

[adhesive]

As an adhesive agent for bonding a polarizing layer and retardation layer or retardation layer and a display device, a pressure-sensitive adhesive, a dry solidification type adhesive agent, and a chemical reaction type adhesive agent are mentioned. As a chemical reaction type adhesive agent, an active energy ray hardening type adhesive agent is mentioned, for example. As the pressure-sensitive adhesive between the polarizing layer and the retardation layer, an adhesive layer formed from a pressure-sensitive adhesive, a dry-solidifying adhesive, or an active energy ray-curable adhesive is preferable. As the adhesive between the retardation layer and the display device, a pressure-sensitive adhesive or active An adhesive layer formed from an energy ray-curable adhesive is preferable.

A pressure-sensitive adhesive may contain a polymer and may contain the solvent normally.

Examples of the polymer include an acrylic polymer, a silicone polymer, polyester, polyurethane, or polyether. Among them, the acrylic pressure-sensitive adhesive containing the acrylic polymer is excellent in optical transparency, has moderate wettability and cohesive force, is excellent in adhesiveness, and further has high weather resistance and heat resistance, so that it floats or peels off under conditions of heating or humidification. It is preferable because the etc. do not occur easily.

As the acrylic polymer, (meth)acrylate in which the alkyl group of the ester moiety is an alkyl group having 1 to 20 carbon atoms such as a methyl group, an ethyl group, or a butyl group (hereinafter, acrylate and methacrylate are collectively referred to as (meth)acrylate. A copolymer of (meth)acrylic monomers having a functional group such as (meth)acrylic acid and (meth)acrylic acid or hydroxyethyl (meth)acrylate is a copolymer of (meth)acrylic acid and (meth)acrylic acid desirable.

The pressure-sensitive adhesive containing such a copolymer is preferable because it is excellent in adhesiveness and can be removed relatively easily without generating an adhesive residue or the like in the display device even when removed after bonding to the display device. 25 degrees C or less is preferable and, as for the glass transition temperature of an acrylic polymer, 0 degrees C or less is more preferable. It is preferable that the mass average molecular weight of such an acrylic polymer is 100,000 or more.

As a solvent, the solvent etc. illustrated as said solvent are mentioned. The pressure-sensitive adhesive may contain a light diffusing agent. A light diffusing agent is an additive which provides light diffusivity to an adhesive, and may just be microparticles|fine-particles which have a refractive index different from the refractive index of the polymer which an adhesive contains. As a light diffusing agent, the microparticles|fine-particles which consist of an inorganic compound, and the microparticles|fine-particles which consist of an organic compound (polymer) are mentioned. Since most of the polymers which the adhesive contains as an active ingredient, including an acrylic polymer, have a refractive index of about 1.4-1.6, it is preferable to select suitably from the light-diffusion agent whose refractive index is 1.2-1.8. The refractive index difference between the polymer which an adhesive contains as an active ingredient, and a light diffusing agent is 0.01 or more normally, and from a viewpoint of the brightness of a display apparatus, and display property, 0.01-0.2 are preferable. The microparticles|fine-particles used as a light diffusing agent are preferably spherical microparticles|fine-particles, and also microparticles|fine-particles close to monodisperse, and the microparticles|fine-particles whose average particle diameter is 2 micrometers - 6 micrometers are more preferable. The refractive index is measured by a general minimum declination method or an Abbe refractometer.

As microparticles|fine-particles which consist of an inorganic compound, aluminum oxide (refractive index 1.76), silicon oxide (refractive index 1.45), etc. are mentioned. As fine particles made of an organic compound (polymer), melamine beads (refractive index 1.57), polymethyl methacrylate beads (refractive index 1.49), methyl methacrylate/styrene copolymer resin beads (refractive index 1.50 to 1.59), polycarbonate beads ( refractive index 1.55), polyethylene beads (refractive index 1.53), polystyrene beads (refractive index 1.6), polyvinyl chloride beads (refractive index 1.46), and silicone resin beads (refractive index 1.46). Content of a light-diffusion agent is 3 mass parts - 30 mass parts with respect to 100 mass parts of polymers normally.

Although the thickness in particular of a pressure-sensitive adhesive is not restrict|limited since it determines with the adhesive force etc., Usually, they are 1 micrometer - 40 micrometers. From points, such as workability and durability, 3 micrometers - 25 micrometers are preferable and, as for the said thickness, 5 micrometers - 20 micrometers are more preferable. By setting the thickness of the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive to 5 µm to 20 µm, brightness when the display device is viewed from the front or from an angle is maintained, and blurring or blurring of the display image can be prevented from occurring.

[Dry solidifying adhesive]

The dry solidifying adhesive may contain the solvent.

As the dry solidifying adhesive, a polymer of a monomer having a protonic functional group such as a hydroxyl group, a carboxyl group or an amino group and an ethylenically unsaturated group, or a urethane resin is contained as a main component, and a polyhydric aldehyde, an epoxy compound, an epoxy resin, a melamine compound , a zirconia compound, and a composition containing a crosslinking agent or a curable compound such as a zinc compound. Examples of the polymer of a monomer having a protonic functional group such as a hydroxyl group, a carboxyl group or an amino group and an ethylenically unsaturated group include an ethylene-maleic acid copolymer, an itaconic acid copolymer, an acrylic acid copolymer, an acrylamide copolymer, a saponified product of polyvinyl acetate; And polyvinyl alcohol-type resin etc. are mentioned.

Examples of the polyvinyl alcohol-based resin include polyvinyl alcohol, partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, acetoacetyl group-modified polyvinyl alcohol, methylol group-modified polyvinyl alcohol, and amino group-modified poly Vinyl alcohol etc. are mentioned. Content of the polyvinyl alcohol-type resin in an aqueous adhesive agent is 1 mass part - 10 mass parts normally with respect to 100 mass parts of water, Preferably they are 1 mass part - 5 mass parts.

As a urethane resin, a polyester-type ionomer type|mold urethane resin etc. are mentioned.

The polyester-based ionomer-type urethane resin as used herein is a urethane resin having a polyester skeleton, and is a resin in which a small amount of an ionic component (hydrophilic component) is introduced. Since such an ionomer type urethane resin becomes an emulsion by emulsifying in water without using an emulsifier, it can be set as an aqueous adhesive agent. When using a polyester ionomer type urethane resin, it is effective to mix|blend a water-soluble epoxy compound as a crosslinking agent.

As the epoxy resin, a polyamide epoxy obtained by reacting epichlorohydrin with a polyamide polyamine obtained by reaction of a polyalkylene polyamine such as diethylenetriamine or triethylenetetramine with a dicarboxylic acid such as adipic acid resin etc. are mentioned. As commercially available products of such polyamide epoxy resin, "Sumirez Resin (registered trademark) 650" and "Sumirez Resin 675" (above, manufactured by Sumika Chemtex Co., Ltd.), "WS-525" (manufactured by Nippon PMC Co., Ltd.), etc. can be heard When mix|blending an epoxy resin, the addition amount is 1 mass part - 100 mass parts normally with respect to 100 mass parts of polyvinyl alcohol-type resin, Preferably they are 1 mass part - 50 mass parts.

The thickness of the pressure-sensitive adhesive layer formed from a dry solidifying adhesive is 0.001 micrometer - 5 micrometers normally, Preferably they are 0.01 micrometer - 2 micrometers, More preferably, they are 0.01 micrometer - 0.5 micrometer. When the pressure-sensitive adhesive layer formed from the dry-solidifying adhesive is too thick, the optically anisotropic layer tends to have poor appearance.

[Active energy ray-curable adhesive]

The active energy ray-curable adhesive may contain the solvent. An active energy ray hardening-type adhesive agent is an adhesive agent which receives irradiation of an active energy ray and hardens|cures.

Examples of the active energy ray-curable adhesive include a cationically polymerizable adhesive containing an epoxy compound and a cationic polymerization initiator, a radically polymerizable adhesive containing an acrylic curing component and a radical polymerization initiator, a cationically polymerizable curing component such as an epoxy compound, and Adhesives that contain both radical polymerizable curing components such as acrylic compounds and further contain a cationic polymerization initiator and a radical polymerization initiator, and adhesives that do not contain these polymerization initiators and are cured by irradiation with an electron beam. can

Especially, the radically polymerizable active energy ray hardening-type adhesive agent containing an acryl-type hardening component and a radical polymerization initiator, and the cationically polymerizable active energy ray hardening-type adhesive agent containing an epoxy compound and a cationic polymerization initiator are preferable. As an acryl-type hardening component, (meth)acrylates, such as methyl (meth)acrylate and hydroxyethyl (meth)acrylate, (meth)acrylic acid, etc. are mentioned. The active energy ray hardening-type adhesive agent containing an epoxy compound may contain compounds other than an epoxy compound further. As a compound other than an epoxy compound, an oxetane compound, an acryl compound, etc. are mentioned.

As a radical polymerization initiator, the photoinitiator mentioned above is mentioned. Commercially available cationic polymerization initiators include "Kayarad" (registered trademark) series (manufactured by Nippon Kayaku Co., Ltd.), "Cyracure UVI" series (manufactured by Dow Chemical Corporation), "CPI" series (manufactured by San Apro Corporation), "TAZ", "BBI" and "DTS" (manufactured by Midori Chemical Co., Ltd.), "Adeka Optomer" series (manufactured by ADEKA Corporation), "RHODORSIL" (registered trademark) (manufactured by Rhodia Corporation), etc. are mentioned. . Content of a radical polymerization initiator and a cationic polymerization initiator is 0.5 mass part - 20 mass parts normally with respect to 100 mass parts of active energy ray hardening-type adhesive agents, Preferably they are 1 mass part - 15 mass parts.

The active energy ray-curable adhesive may further contain an ion trapping agent, an antioxidant, a chain transfer agent, a tackifier, a thermoplastic resin, a filler, a flow regulator, a plasticizer, an antifoaming agent, and the like.

In the present specification, an active energy ray is defined as an energy ray capable of generating an active species by decomposing a compound that generates an active species. Examples of such active energy rays include visible light, ultraviolet rays, infrared rays, X-rays, α-rays, β-rays, γ-rays, and electron beams, and ultraviolet rays and electron beams are preferable. Preferred UV irradiation conditions are the same as those for polymerization of the polymerizable liquid crystal compound described above.

[Refractive index of each layer of the laminate]

When a layer A and another layer B are laminated immediately below, assuming that the refractive index of the layer A is nA and the refractive index of the layer B is nB, the layer A and the layer when light is incident from the direction perpendicular to the layer A The interfacial reflectance in B is represented by the following formula (K).

Interfacial reflectance (%) = (n _A - n _B ) ² /(n _A + n _B ) ² × 100 ... (K)

For this reason, when the refractive index difference of the adjacent layers of a laminated body is large, the loss by interfacial reflection becomes large. In the elliptically polarizing plate made of a laminate, in order to reduce the influence of loss due to interfacial reflection, the difference in refractive index between adjacent layers is preferably 0.20 or less, more preferably 0.15 or less, and still more preferably 0.10 or less.

[Method for producing a polarizing layer or retardation layer]

Hereinafter, the polarizing layer or retardation layer of the present invention may be referred to as an optically anisotropic layer. In addition, the composition for forming a polarizing layer or the composition for forming a retardation layer may be referred to as a composition for forming an optically anisotropic layer. The manufacturing method of a polarizing layer and retardation layer may be same or different.

[Application of the composition for forming an optically anisotropic layer]

An optically anisotropic layer may be formed by applying the composition for forming an optically anisotropic layer on the above-described transparent substrate or alignment layer. As a method of applying the composition for forming an optically anisotropic layer on a substrate, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, a CAP coating method, a slit coating method, a micro gravure method, a die coating method, an inkjet method, etc. can be heard Moreover, the method of apply|coating using coaters, such as a dip coater, a bar coater, and a spin coater, etc. are mentioned. Among them, in the case of continuous application in a roll to roll format, a coating method by micro gravure method, inkjet method, slit coating method, and die coating method is preferable, and applying to a sheet-fed substrate such as glass In this case, a spin coating method with high uniformity is preferable. In the case of application in a roll-to-roll format, an alignment film may be formed by applying a composition for forming a photo-alignment film to a substrate, and the composition for forming an optically anisotropic layer may be continuously applied on the obtained alignment film.

[Drying of the composition for forming an optically anisotropic layer]

As a drying method for removing the solvent contained in the composition for optically anisotropic layer formation, natural drying, ventilation drying, heat drying, reduced pressure drying, and the method combining these are mentioned, for example. Especially, natural drying or heat drying is preferable. The range of 0-200 degreeC is preferable, as for drying temperature, the range of 20-150 degreeC is more preferable, and the range of 50-130 degreeC is still more preferable. As for drying time, 10 second - 20 minutes are preferable, More preferably, they are 30 second - 10 minutes. The composition for forming a photo alignment layer and the alignment polymer composition may be dried in the same manner.

[Polymerization of polymerizable liquid crystal compound]

As a method of superposing|polymerizing a polymerizable liquid crystal compound, photopolymerization is preferable. Photopolymerization is performed by irradiating an active energy ray to the laminated body to which the composition for optically anisotropic layer formation containing a polymerizable liquid crystal compound was apply|coated on a base material or an alignment film. Examples of the active energy ray to be irradiated include the type of the polymerizable liquid crystal compound contained in the dry film (in particular, the type of the photopolymerizable functional group of the polymerizable liquid crystal compound), the type of the photopolymerization initiator in the case of containing a photopolymerization initiator, and appropriately selected depending on their amount. Specifically, one or more types of light selected from the group consisting of visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays, and γ-rays can be mentioned. Among them, ultraviolet light is preferable from the viewpoint of being able to easily control the progress of the polymerization reaction and being widely used in the art as a photopolymerization device, so that photopolymerization is possible by ultraviolet light. It is preferable to select the kind of liquid crystal compound.

Examples of the light source of the active energy ray include a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, a halogen lamp, a carbon arc lamp, a tungsten lamp, a gallium lamp, an excimer laser, a wavelength range of 380 An LED light source emitting light of -440 nm, a chemical lamp, a black light lamp, a microwave excited mercury lamp, a metal halide lamp, etc. are mentioned.

Ultraviolet irradiation intensity|strength is 10 mW/cm<2> - 3,000 mW/cm<2> normally. Ultraviolet irradiation intensity|strength, Preferably it is intensity|strength in the wavelength range effective for activation of a cationic polymerization initiator or a radical polymerization initiator. The time for irradiating light is normally 0.1 second - 10 minutes, Preferably they are 0.1 second - 5 minutes, More preferably, they are 0.1 second - 3 minutes, More preferably, they are 0.1 second - 1 minute. When irradiated once or plural times with such ultraviolet irradiation intensity, the accumulated light quantity is usually 10 mJ/cm 2 to 3,000 mJ/cm 2 , preferably 50 mJ/cm 2 to 2,000 mJ/cm 2 , more preferably 100 mJ /cm2 - 1,000 mJ/cm2. When the amount of accumulated light is less than or equal to this range, curing of the polymerizable liquid crystal compound becomes insufficient. Conversely, when the amount of integrated light is equal to or greater than this range, the elliptically polarizing plate including the optically anisotropic layer may be colored.

[display device]

The present invention can provide a display device including the retardation plate of the present invention as one of the embodiments. Moreover, the said display device may contain the elliptically polarizing plate which concerns on the said embodiment.

The said display device is a device which has a display mechanism, and contains a light emitting element or a light emitting device as a light emitting source. Examples of the display device include a liquid crystal display device, an organic electroluminescence (EL) display device, an inorganic electroluminescence (EL) display device, a touch panel display device, an electron emission display device (field emission display device (FED, etc.), Surface field emission display (SED)), electronic paper (display using electronic ink or electrophoretic element), plasma display, projection display (grating light valve (GLV) display, digital micromirror device (DMD)) display devices) and piezoelectric ceramic displays.

The liquid crystal display device includes any of a transmissive liquid crystal display device, a transflective liquid crystal display device, a reflective liquid crystal display device, a direct view liquid crystal display device, and a projection type liquid crystal display device. These display devices may be a display device that displays a two-dimensional image or a stereoscopic display device that displays a three-dimensional image. In particular, as a display device provided with the retardation layer which consists of this invention, and a polarizing layer, an organic electroluminescent display and a touchscreen display device are preferable.

Example

Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to these examples. "%" and "part" in an Example and a comparative example are "mass %" and a "part by mass" unless otherwise specified.

The polymer film, apparatus, and measuring method used in Examples 1-6 and Comparative Examples 1-2 are as follows.

- ZF-14 manufactured by Nippon Zeon Co., Ltd. was used for the cycloolefin polymer (COP) film.

- AGF-B10 by Kasuga Electric Co., Ltd. was used for the corona treatment apparatus.

- Corona treatment was performed once under the conditions of 0.3 kW of output and 3 m/min of processing speed using the said corona treatment apparatus.

- SPOT CURE SP-7 in which the polarizer unit of the Ushio Electric Co., Ltd. product was formed was used for the polarization|polarized-light UV irradiation apparatus.

· LEXT manufactured by Olympus Co., Ltd. was used for the laser microscope.

- Ushio Electric Co., Ltd. product Unicure VB-15201BY-A was used for a high-pressure mercury-vapor lamp.

· The in-plane retardation value and the axial angle of the retardation layer and the polarizing layer were measured using KOBRA-WPR manufactured by Oji Instruments Corporation.

- The measurement of the optical characteristic of a polarizing layer was measured using Shimadzu Corporation UV-3150.

- The film thickness was measured using the ellipsometer M-220 by the Nippon Spectroscopy Co., Ltd. product.

[Preparation of composition for forming alignment layer A and B]

The composition for orientation layer A and B formation was obtained by mixing 5 parts of photo-alignment materials of the following structure and 95 parts of cyclopentanone (solvent) as a component, and stirring the obtained mixture at 80 degreeC for 1 hour. In addition, the weight average molecular weight of the following photo-alignment material used for the orientation layer A is as Table 1, the molecular weight of the following photo-alignment material used for 30000 and the orientation film B.

[Preparation of the composition for forming a retardation layer]

A polymerizable liquid crystal compound A having the following structure, a polyacrylate compound (leveling agent) (BYK-361N; manufactured by BYK-Chemie), and the following polymerization initiator were mixed as components to obtain a composition for forming a retardation layer.

polymerizable liquid crystal compound A

The polymerizable liquid crystal compound A was manufactured by the method of Unexamined-Japanese-Patent No. 2010-31223. The amount of the polyacrylate compound was 0.01 parts with respect to 100 parts of the polymerizable liquid crystal compound A.

As a polymerization initiator, 2-dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one (Irgacure 369 (Irg369); BASF Japan Co., Ltd. with respect to 100 parts of polymerizable liquid crystal compound A) preparation) was added in 6 parts.

Furthermore, N-methyl-2-pyrrolidone (NMP) was added as a solvent so that solid content concentration might be 13 %, and the composition for phase difference layer formation was obtained by stirring at 80 degreeC for 1 hour.

[Preparation of the composition for forming a polarizing layer]

The composition for polarizing layer formation was obtained by mixing the following components and stirring at 80 degreeC for 1 hour. As a dichroic dye, the azo dye of the Example of Unexamined-Japanese-Patent No. 2013-101328 was used. The polymerizable liquid crystal compound represented by formulas (1-6) and (1-7) is described in lub et al., Recl. Trav. Chim. It was prepared according to the method described in Pays-Bas, 115, 321-328 (1996).

Polymeric liquid crystal compounds:

75 copies

25 copies

Dichroic pigment 1:

polyazo dyes; 2.5 parts of compound (1-8)

2.5 parts of compound (1-5)

2.5 parts of compound (1-16)

polymerization initiator;

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

leveling agent;

1.2 parts of polyacrylate compound (BYK-361N; manufactured by BYK-Chemie)

solvent; 250 parts o-xylene

[Example 1]

[Production of retardation layer]

On a COP film (ZF-14-50) manufactured by Nippon Zeon Co., Ltd., the composition for forming an orientation layer A was applied with a bar coater, dried at 80° C. for 1 minute, and polarized UV irradiation device (SPOT CURE SP-7; Ushio Electric) Co., Ltd.) was used, and polarized light UV exposure was performed at an axial angle of 45° with an accumulated light amount of 100 mJ/cm 2 . It was 100 nm when the film thickness of the obtained orientation layer A was measured with an ellipsometer.

Subsequently, on the alignment layer A, the prepared composition for forming a retardation layer was applied using a bar coater, dried at 120° C. for 1 minute, and then a high-pressure mercury lamp (Unicure VB-15201BY-A, manufactured by Ushio Electric Co., Ltd.) ), by irradiating ultraviolet rays from the side on which the composition of the retardation layer was applied (in a nitrogen atmosphere, the accumulated light amount at a wavelength of 313 nm: 500 mJ/cm 2 ), thereby forming a laminate comprising an alignment layer A and a retardation layer formed.

Then, the laminated body phase containing the obtained retardation layer was processed once using the corona treatment apparatus (AGF-B10, Kasuga Electric Co., Ltd. product) under the conditions of an output of 0.3 kW and a processing speed of 3 m/min. A composition for forming an alignment layer B was applied with a bar coater to the corona-treated surface, dried at 80°C for 1 minute, and 100 mJ/ Polarized UV exposure was performed at an axial angle of 90° with an accumulated light quantity of cm 2 . It was 150 nm when the film thickness of the obtained orientation layer B was measured with an ellipsometer.

After apply|coating the composition for polarizing layer formation using the bar coater, the dry coating film which the polymeric liquid crystal compound and the dichroic dye orientated was obtained by drying for 1 minute in the drying oven set to 120 degreeC. After naturally cooling this dried coating film to room temperature, using a high-pressure mercury lamp (Unicure VB-15201BY-A, manufactured by Ushio Electric Co., Ltd.), ultraviolet rays are irradiated (under nitrogen atmosphere, wavelength: 365 nm, integration in wavelength 365 nm) Amount of light: 1000 mJ/cm 2 ) to obtain an elliptically polarizing plate including a retardation layer and a polarizing layer in which a polymerizable liquid crystal compound was polymerized to prepare a polarizing layer.

[Measurement of retardation value of elliptically polarizing plate]

As a result of measuring in-plane retardation values at a wavelength of 450 nm, a wavelength of 550 nm, and a wavelength of 650 nm of the obtained elliptically polarizing plate, the retardation values at each wavelength are Re(450) = 116 nm, Re(550) = 140 nm, Re( 650) = 144 nm, and the relationship between the in-plane retardation values was as follows.

Re(450)/Re(550) = 0.83

Re(650)/Re(550) = 1.03

(Wherein, Re(450) is an in-plane retardation value for light with a wavelength of 450 nm, Re(550) is an in-plane retardation value for light with a wavelength of 550 nm, and Re(650) is for light with a wavelength of 650 nm. It represents the in-plane phase difference value.)

That is, the retardation layer A had the optical characteristic shown by following formula (1)-(3).

100 nm < Re(550) < 160 nm... (One)

Re(450)/Re(550) ≤ 1.0 ... (2)

1.00 ≤ Re(650)/Re(550) … (3)

In addition, the slow axis direction of the retardation layer was 45 degrees, and the absorption axis angle of the polarizing layer was 0 degrees. Ideally, the angle between the slow axis of the retardation plate used for the circular polarizing plate and the absorption axis of the polarizing plate is 45°. The angle between the slow axis of the retardation layer and the absorption axis of the polarizing layer is 45° It was found that no deviation occurred.

[Measurement of polarization degree and single transmittance]

The polarization degree and the single transmittance|permeability of the obtained elliptically polarizing plate were measured as follows. The transmittance (T ¹ ) in the transmission axis direction and the transmittance (T ² ) in the absorption axis direction were measured by a double beam method using a spectrophotometer (UV-3150 manufactured by Shimadzu Corporation) in which a folder with a polarizer was set. It measured in the wavelength range of 2 nm step 380-680 nm. Using the following formulas (p) and (q), the single transmittance and the polarization degree at each wavelength are calculated, and the visibility is corrected by the 2 degree field of view (C light source) of JIS Z 8701, and the visibility is corrected alone. When the transmittance|permeability (Ty) and the visibility correction|amendment polarization degree (Py) were computed, the single transmittance|permeability was 42 %, and the polarization degree was 97 %, and it confirmed that it was a value useful as a polarizing plate.

Single transmittance (%) = (T ¹ + T ² )/2 (p)

Polarization degree (%) = {(T ¹ - T ² )/(T ¹ + T ² )} × 100 (q)

[Refractive index of elliptically polarizing plate]

It was as follows when the refractive index of each layer was measured according to JISK7142 using the refractometer ("multi-wavelength Abbe refractometer DR-M4" manufactured by Atago Corporation).

Description...1.53

Alignment film A...1.55

Retardation layer...1.62

Alignment film B...1.55

Polarizing layer...1.54

[Examples 2 to 6]

An elliptically polarizing plate was produced in the same manner as in Example 1 except that the film thickness of the alignment layer B was adjusted by changing the thickness of the wire bar at the time of forming the alignment layer B when the photo alignment material was applied with a bar coater.

[Comparative Examples 1 and 2]

In the formation of the alignment layer B, the retardation layer and the polarizing layer were formed in the same manner as in Example 1 except that the film thickness of the polarizing layer B was adjusted by changing the thickness of the wire bar at the time of bar coater application of the photo-aligning material. A circularly polarizing plate containing

Table 1 shows the results of measuring the optical properties of the polarizing layers described in Examples and Comparative Examples.

The elliptically polarizing plate of the Example was able to be manufactured, without producing|generating the axis shift of a polarizing layer, and generation|occurrence|production of an orientation defect.

Claims (13)

An elliptically polarizing plate in which an alignment layer A, a retardation layer, an alignment layer B and a polarizing layer are formed in this order on a transparent substrate,
The elliptically polarizing plate has an ellipticity of 79% or more at a wavelength of 550 nm,
The optical axes of the polarizing layer and the retardation layer are not substantially parallel,
The retardation layer is a film composed of a polymer of a polymerizable liquid crystal compound,
The alignment layer B is a film having a thickness of 80 nm to 800 nm,
The alignment layer B is a photo-alignment film,
The polarizing layer is an elliptically polarizing plate in which a dichroic dye is oriented in a film composed of a polymer of a polymerizable liquid crystal compound. The method of claim 1,
An elliptically polarizing plate having an average refractive index of all of the transparent substrate, the alignment layer A, the retardation layer, the alignment layer B, and the polarizing layer in the range of 1.4 to 1.7. The method of claim 1,
An elliptically polarizing plate whose refractive index difference between adjacent layers is 0.2 or less. The method of claim 1,
An elliptically polarizing plate having an angle between the polarizing layer and the optical axis of the retardation layer in the range of 40° to 50°. The method of claim 1,
An elliptically polarizing plate wherein the alignment layer A is a photo alignment layer. The method of claim 1,
An elliptically polarizing plate wherein the alignment layer A and the alignment layer B are photo alignment layers containing a cinnamoyl group. The method of claim 1,
An elliptically polarizing plate wherein the alignment layer A and the alignment layer B are a photo alignment film containing a resin having a weight average molecular weight of 20000 to 50000. The method of claim 1,
An elliptically polarizing plate wherein the polarizing layer is a film composed of a polymer in a smectic liquid crystal state. The method of claim 1,
The elliptically polarizing plate whose said dichroic dye is an azo dye. The method of claim 1,
An elliptically polarizing plate in which the retardation layer satisfies all of the following formulas.
100 nm < Re(550) < 160 nm... (One)
Re(450)/Re(550) ≤ 1.0 ... (2)
1.00 ≤ Re(650)/Re(550) … (3)
(Re(450), Re(550), and Re(650) represent in-plane retardation at wavelengths of 450 nm, 550 nm, and 650 nm, respectively.) The liquid crystal display device provided with the elliptically polarizing plate in any one of Claims 1-10. The organic electroluminescence display provided with the elliptically polarizing plate in any one of Claims 1-10. on a transparent substrate,
A step (1) of applying a composition containing an alignment material A and a solvent and irradiating polarized UV light after drying to form an alignment layer A;
A step (2) of forming a retardation layer by coating a composition containing a polymerizable liquid crystal compound, a polymerization initiator and a solvent on the alignment layer A, drying it, and then irradiating it with UV to polymerize it in a liquid crystal state;
A step (3) of applying a composition containing an alignment material B and a solvent and irradiating polarized UV light after drying to form an alignment layer B which is a photo alignment film having a thickness of 80 nm to 800 nm;
a step (4) of forming a polarizing layer by coating a composition containing a polymerizable liquid crystal compound, a dichroic dye, a polymerization initiator and a solvent on the alignment layer B, drying it and then irradiating with UV to polymerize it in a liquid crystal state;
The manufacturing method of the elliptically polarizing plate whose ellipticity in wavelength 550nm is 79 % or more.