WO2015068678A1 - Polarizing plate and method for manufacturing polarizing plate - Google Patents

Abstract

　The present invention provides: a polarizing plate comprising, in sequence, an optical anisotropic layer, a polarizer, and a hard-coat layer, the optical anisotropic layer being formed from a composition comprising a liquid-crystal compound, and having solely an adhesive layer (1) between the optical anisotropic layer and the polarizer, or solely a protective layer provided to the surface of the adhesive layer (1) and the polarizer; and a manufacturing method therefor. The above configuration makes it possible to obtain a polarizing plate in which an optical anisotropic layer having diverse optical compensation abilities has been bonded with a variety of polarizers in a minimal configuration.

Description

Polarizing plate and manufacturing method of polarizing plate

The present invention relates to a polarizing plate and a manufacturing method of the polarizing plate. The present invention particularly relates to a polarizing plate having an optically anisotropic layer and a hard coat layer formed from a composition containing a liquid crystal compound, and a method for producing the same.

As the market for smartphones and tablet PCs expands, displays are increasingly required to be thinner. In this trend, the retardation film used for compensating the viewing angle of the liquid crystal display device is also required to be thin. Many examples have been known in which a film having a predetermined retardation is used as a protective film for a polarizing plate, and the retardation is realized by alignment of a liquid crystal compound (for example, Patent Documents 1 and 2), including a liquid crystal compound. Since the optically anisotropic layer formed by photocuring of the composition has low self-supporting property, it is usually formed on a support such as a cellulose acylate polymer film and used as it is. The thinning of the anisotropic layer has to be studied in a form including a support. On the other hand, Patent Document 3 discloses that a thin polarizing plate is realized by applying a composition containing a liquid crystal compound directly on the surface of a polarizing film to form an optically anisotropic layer. A specific example having an optically anisotropic layer on the surface and a light diffusion layer formed from a hard coat coating solution on the other surface is shown.

JP 2013-050572 A JP 2011-133549 A JP 2004-53770 A

An object of the present invention is to provide a polarizing plate having a small film thickness. The present invention particularly relates to a polarizing plate having an optically anisotropic layer and a hard coat layer formed from a composition containing a liquid crystal compound, and having a minimum number of optically anisotropic layers having various optical compensation capabilities. It is an object of the present invention to provide a thin film polarizing plate manufactured by a method capable of being bonded to various polarizers and a manufacturing method thereof.

The inventors of the present invention have made extensive studies to solve the above problems, and the configuration of a thin film polarizing plate having various optical compensation capabilities using an optically anisotropic layer formed on a temporary support is optically anisotropic. It was found that this is possible without defects in the sex layer. And it is noticed that this is in line with the demand for thinner displays, especially smaller displays, and is suitable for use as a front-side polarizing plate for liquid crystal display devices or a polarizing plate for organic EL display devices. The present invention was completed through repeated studies of the configuration.
That is, the present invention provides the following <1> to <14>.

<1> A polarizing plate,
Including an optically anisotropic layer, a polarizer, and a hard coat layer in this order,
The optically anisotropic layer is a layer formed from a composition containing a liquid crystal compound,
A polarizing plate comprising only the adhesive layer 1 or only the protective layer provided on the surface of the adhesive layer 1 and the polarizer between the optically anisotropic layer and the polarizer.
<2> The polarizing plate according to <1>, comprising a transparent support between the polarizer and the hard coat layer, wherein the hard coat layer is in direct contact with the transparent support.
<3> The polarizing plate according to <2>, wherein the transparent support comprises cellulose acylate, (meth) acrylic polymer, cycloolefin polymer, or polyester.
<4> The polarizing plate according to <2> or <3>, which includes only the adhesive layer 2 between the transparent support and the polarizer.

<5> The polarizing plate according to any one of <1> to <4>, wherein the adhesive layer 1 is a layer formed from an active energy ray-curable adhesive.
<6> The polarizing plate according to any one of <1> to <5>, wherein the optically anisotropic layer has a thickness of 0.5 μm to 3 μm.
<7> The polarizing plate according to any one of <1> to <6>, which includes only the adhesive layer 1 between the optically anisotropic layer and the polarizer.
<8> Only the protective layer provided on the surface of the adhesive layer 1 and the polarizer is included between the optically anisotropic layer and the polarizer, and the protective layer is cellulose acylate, (meth) acrylic polymer Or a polarizing plate according to any one of <1> to <7>, comprising a cycloolefin polymer.
<9> including a temporary support,
The optically anisotropic layer is a layer formed from a composition containing a liquid crystal compound applied directly on the surface of the temporary support or directly on an alignment layer provided on the temporary support <1> to The polarizing plate as described in any one of <8>.

<10> A method for producing a polarizing plate according to any one of <1> to <8>,
(1) Prepare the following transfer materials:
Including a temporary support and an optically anisotropic layer,
The temporary support has a rubbed surface, or an orientation layer is provided on the surface,
The optically anisotropic layer is a transfer material which is a layer formed from a composition containing a liquid crystal compound directly applied to the rubbing-treated surface or the alignment layer,
(2) Laminating the optically anisotropic layer on a film containing a polarizer and adhering it directly or via another layer;
(3) Laminating a hard coat layer on the surface of the film containing the polarizer opposite to the surface on which the transfer material is adhered; and (4) peeling the temporary support and the optically anisotropic layer. Separating the manufacturing method.
<11> In (2), the transfer material is directly on the film containing the polarizer so that the surface on the optically anisotropic layer side with respect to the temporary support is on the film side containing the polarizer. Glued and
(2) and (4) are the manufacturing methods as described in <10> performed in this order.

<12> A method for producing a polarizing plate according to <9>,
(1) Prepare the following transfer materials:
Including a temporary support and an optically anisotropic layer,
The temporary support has a rubbed surface, or an orientation layer is provided on the surface,
The optically anisotropic layer is a transfer material which is a layer formed from a composition containing a liquid crystal compound directly applied to the rubbing-treated surface or the alignment layer,
(12) The transfer material is directly adhered to a film containing a polarizer such that the surface on the optically anisotropic layer side is on the film side containing the polarizer, with respect to the temporary support. (3) A manufacturing method comprising laminating a hard coat layer on a surface opposite to a surface to which the transfer material of the film including the polarizer is bonded.
<13> With respect to the polarizer of the laminate obtained by bonding (2) or (12) using an active energy ray-curable adhesive and laminating the transfer material on a film containing the polarizer The method according to any one of <10> to <12>, which is performed by irradiating active energy rays from the surface on the optically anisotropic layer side.
<14> The production method according to any one of <10> to <13>, wherein the polarizer in the film containing the polarizer and the optically anisotropic layer are directly bonded.

According to the present invention, a thin film polarizing plate is provided. According to the present invention, there is provided a polarizing plate in which an optically anisotropic layer having various optical compensation capabilities formed from a composition containing a liquid crystal compound is bonded to various polarizers with a minimum configuration, A polarizing plate suitable for use as a front polarizing plate of a liquid crystal display device or a polarizing plate of an organic EL display device is provided.

It is a figure which shows the example of the laminated constitution of the polarizing plate of this invention.

Hereinafter, the present invention will be described in detail.
In the present specification, “˜” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value. In this specification, unless otherwise specified, the term “polarizing plate” is cut into a size that can be incorporated into a long polarizing plate and a liquid crystal display device (in this specification, “cutting” includes “punching” and “ It is also used in the sense of including both of the polarizing plates. In this specification, “polarizer” (sometimes referred to as “polarizing film”) and “polarizing plate” are used separately, and “polarizing plate” is a laminate having a film on at least one side of “polarizer”. Means.
In the present specification, the description “(meth) acrylate” means “one or both of acrylate and methacrylate”. The same applies to “(meth) acrylic acid” and the like.

In this specification, Re (λ) represents in-plane retardation at wavelength λ. Re (λ) can be measured using a polarization phase difference analyzer AxoScan manufactured by AXOMETRICS. Alternatively, Re (λ) may be measured by making light having a wavelength of λ nm incident in the normal direction of the film in KOBRA 21ADH or WR (manufactured by Oji Scientific Instruments).

In this specification, the measurement wavelength is 550 nm unless otherwise specified. For example, when it is simply described as Re, Re (550) is indicated. Further, in this specification, being optically isotropic means that the absolute value of in-plane retardation (Re (550)) is 10 nm or less. Having in-plane retardation means that Re (550) is larger than 10 nm.
Further, in the present specification, regarding the angle (for example, an angle such as “90 °”) and the relationship (for example, “orthogonal”, “parallel”, “crossing at 45 °”, etc.), the technical field to which the present invention belongs. The range of allowable error is included. For example, it means that the angle is within the range of strict angle ± 10 °, and the error from the strict angle is preferably 5 ° or less, and more preferably 3 ° or less.

[Polarizer]
The polarizing plate of the present invention includes an optically anisotropic layer, a polarizer, and a hard coat layer. The optically anisotropic layer is only required to be disposed on one or both surfaces of the polarizer, and is preferably on either surface. The hard coat layer is provided on the surface opposite to the surface on which the optically anisotropic layer is provided with respect to the polarizer. When the optically anisotropic layer is on both sides of the polarizer, the hard coat layer may be provided on any surface. Furthermore, the polarizing plate includes other layers such as an alignment layer for alignment of the liquid crystal compound during the formation of the optically anisotropic layer, a protective layer for protecting the surface of the polarizer or the optically anisotropic layer. You may go out.
An example of the layer structure of the polarizing plate of the present invention is shown in FIG.
The thickness of the polarizing plate is not particularly limited, but may be about 50 μm to 500 μm. In particular, the polarizing plate of the present invention can be formed with a thin film of 200 μm or less, 150 μm or less, 120 μm or less, 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less.

[Transfer material]
For the production of the polarizing plate of the present invention, a transfer material containing a temporary support and an optically anisotropic layer can be used. By passing the optically anisotropic layer from the transfer material onto the film containing the polarizer, the coated optically anisotropic layer is formed without depending on the type or properties of the film containing the polarizer. In addition, it is possible to form optically anisotropic layers having various liquid crystal compound alignment forms using various liquid crystal compounds. For example, the heating process required in the process of forming the optically anisotropic layer may affect the properties of the polarizer. However, the manufacturing method using the transfer material may affect the polarizer without affecting the polarizer. An isotropic layer can be produced.

The transfer material is a material that can provide an optically anisotropic layer. The temporary support may or may not be peeled off. In the present specification, an object transferred to a film including a polarizer, that is, an object bonded to a film including a polarizer may be referred to as a “transfer body”. In the present specification, the transfer body is a film including an optically anisotropic layer obtained by peeling a temporary support from a transfer material.
The transfer material may include an alignment layer for aligning the liquid crystal compound when forming the optically anisotropic layer. In this case, the alignment layer and the optically anisotropic layer are preferably in contact with each other. In the transfer material including the alignment layer, the temporary support and the alignment layer may be in contact with each other. The transfer material may include other layers such as a release layer and a release layer.

The transfer material is produced by a method including forming an optically anisotropic layer by directly applying a composition containing a liquid crystal compound to the surface of the temporary support or the surface of the alignment layer provided on the temporary support. be able to. Preferably, the transfer material is formed by directly applying a polymerizable composition containing a liquid crystal compound to the surface of the temporary support or the surface of the alignment layer provided on the temporary support, and heating or irradiating the obtained application layer. The polymerizable composition containing a liquid crystal compound can be cured to form an optically anisotropic layer.
Hereinafter, each layer included in the polarizing plate or the transfer material will be described in detail.

[Optically anisotropic layer]
The optically anisotropic layer is a layer having at least one incident direction in which retardation is not substantially zero when the retardation is measured, and is a layer having optical properties that are not isotropic. The optically anisotropic layer used in the present invention is a layer formed from a composition containing a liquid crystal compound. Preferably, the optically anisotropic layer may be formed by irradiating a polymerizable composition containing a liquid crystal compound with light to polymerize the liquid crystal compound. The polymerizable composition includes a liquid crystal compound having at least one polymerizable group as long as the liquid crystal compound is polymerized by the polymerizable group by light irradiation or heating. The polymerizable composition is preferably applied directly to the alignment layer provided on the temporary support. The coating layer is further dried at room temperature or the like, or heated (for example, heating at 50 ° C. to 150 ° C., preferably 80 ° C. to 120 ° C.) to align the liquid crystal compound molecules in the layer. It is only necessary to form an optically anisotropic layer by polymerizing and fixing this.

The film thickness of the optically anisotropic layer is 10 μm or less, less than 8 μm, 7 μm or less, 6 μm or less, 5 μm or less, 4 μm or less, 3 μm or less, 2 μm or less, 1.9 μm or less, 1.8 μm or less, 1.7 μm or less, 1 .6 μm or less, 1.5 μm or less, 1.4 μm or less, 1.3 μm or less, 1.2 μm or less, 1.1 μm or less, or 1 μm or less, or 0.2 μm or more, 0.3 μm or more, 0 It may be 0.4 μm or more, 0.5 μm or more, 0.6 μm or more, 0.7 μm or more, 0.8 μm or more, or 0.9 μm or more.
The optically anisotropic layer is also preferably transparent.

[Two or more optically anisotropic layers]
The polarizing plate may contain two or more optically anisotropic layers. Two or more optically anisotropic layers may be in direct contact with each other in the normal direction, or other layers such as an alignment layer may be sandwiched therebetween. The compositions forming two or more layers may be the same or different. For example, in a combination of two optically anisotropic layers, it may be a combination of layers formed from a composition containing a rod-like liquid crystal compound, or a combination of layers formed from a composition containing a discotic liquid crystal compound, A combination of a layer formed from a composition containing a rod-like liquid crystal compound and a layer formed from a composition containing a discotic liquid crystal compound may be used. When the polarizing plate includes two or more optically anisotropic layers, the previously prepared optically anisotropic layer may function as an alignment layer of the optically anisotropic layer formed later. At this time, the previously produced optically anisotropic layer may be rubbed. When two or more optically anisotropic layers are included, the total thickness of the optically anisotropic layers is preferably the above film thickness.

The two optically anisotropic layers may have a function as a λ / 4 retardation plate, for example. The λ / 4 retardation plate functions as a circularly polarizing plate in combination with a polarizer (linear polarizer).
Retardation plates have a great many applications, and are already used for reflective LCDs, transflective LCDs, brightness enhancement films, organic EL display devices, touch panels, and the like. For example, an organic EL (organic electroluminescence) element has a structure in which layers having different refractive indexes are laminated or a structure using a metal electrode, so that external light is reflected at the interface of each layer, causing problems such as a decrease in contrast and reflection. May occur. Therefore, conventionally, a circularly polarizing plate composed of a phase difference plate and a polarizing film has been used for an organic EL display device, an LCD display device, and the like in order to suppress adverse effects due to external light reflection.

[Liquid Crystal Compound]
Examples of the liquid crystal compound include a rod-like liquid crystal compound and a disk-like liquid crystal compound.
Examples of the rod-like liquid crystal compound include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines, Phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles are preferably used. In addition to the above low-molecular liquid crystalline molecules, high-molecular liquid crystalline molecules can also be used.

The rod-like liquid crystal compound is more preferably fixed in orientation by polymerization, and examples of the polymerizable rod-like liquid crystal compound include those described in Makromol. Chem. 190, 2255 (1989), Advanced Materials 5, 107 (1993), U.S. Pat. Nos. 4,683,327, 5,622,648, 5,770,107, WO 95/22586, 95/24455, 97/97. No. 0600, No. 98/23580, No. 98/52905, JP-A-1-272551, JP-A-6-16616, JP-A-7-110469, JP-A-11-80081, JP-A-2001-328773, JP-A-2001-328773 The compounds described in JP 2013-050583 A can be used. Further, the polymerizable rod-like liquid crystal compound is preferably a polymerizable rod-like liquid crystal compound represented by the following general formula (1).

General formula (1) Q ¹ -L ¹ -Cy ¹ -L ^2- (Cy ² -L ³ ) n-Cy ³ -L ⁴ -Q ²
(In General Formula (1), Q ¹ and Q ² are each independently a polymerizable group, L ¹ and L ⁴ are each independently a divalent linking group, and L ² and L ³ are each independently a single group. A bond or a divalent linking group, Cy ¹ , Cy ² and Cy ³ are divalent cyclic groups, and n is 0, 1, 2 or 3.)

Hereinafter, the polymerizable rod-like liquid crystal compound represented by the general formula (1) will be described.
In general formula (1), Q ¹ and Q ² are each independently a polymerizable group. The polymerization reaction of the polymerizable group is preferably addition polymerization (including ring-opening polymerization) or condensation polymerization. In other words, the polymerizable group is preferably a functional group capable of addition polymerization reaction or condensation polymerization reaction. Examples of polymerizable groups are shown below.

Among the above, preferred polymerizable groups include acrylic groups and methacrylic groups. In particular, it is preferable that both Q ¹ and Q ² in the general formula (1) are an acryl group or a methacryl group.

In general formula (1), L ¹ and L ⁴ are each independently a divalent linking group. L ¹ and L ⁴ each independently comprises —O—, —S—, —CO—, —NR—, —C═N—, a divalent chain group, a divalent cyclic group, and combinations thereof. A divalent linking group selected from the group is preferred. R is an alkyl group having 1 to 7 carbon atoms or a hydrogen atom. R is preferably an alkyl group having 1 to 4 carbon atoms or a hydrogen atom, more preferably a methyl group, an ethyl group or a hydrogen atom, and most preferably a hydrogen atom.

The example of the bivalent coupling group which consists of a combination is shown below. Here, the left side is coupled to Q (Q ¹ or Q ² ), and the right side is coupled to Cy (Cy ¹ or Cy ³ ).

L-1: —CO—O—divalent chain group —O—
L-2: —CO—O—divalent chain group —O—CO—
L-3: —CO—O—divalent chain group —O—CO—O—
L-4: —CO—O—divalent chain group—O—divalent cyclic group—
L-5: —CO—O—divalent chain group —O—divalent cyclic group —CO—O—
L-6: —CO—O—divalent chain group —O—divalent cyclic group —O—CO—
L-7: —CO—O—Divalent chain group—O—Divalent cyclic group—Divalent chain group—
L-8: —CO—O—divalent chain group—O—divalent cyclic group—divalent chain group —CO—O—
L-9: —CO—O—Divalent chain group—O—Divalent cyclic group—Divalent chain group —O—CO—
L-10: —CO—O—divalent chain group—O—CO—divalent cyclic group—
L-11: —CO—O—divalent chain group —O—CO—divalent cyclic group —CO—O—
L-12: —CO—O—divalent chain group —O—CO—divalent cyclic group —O—CO—
L-13: —CO—O—Divalent chain group—O—CO—Divalent cyclic group—Divalent chain group—
L-14: —CO—O—divalent chain group—O—CO—divalent cyclic group—divalent chain group—CO—O—
L-15: —CO—O—Divalent chain group—O—CO—Divalent cyclic group—Divalent chain group—O—CO—
L-16: —CO—O—divalent chain group—O—CO—O—divalent cyclic group—
L-17: —CO—O—divalent chain group —O—CO—O—divalent cyclic group —CO—O—
L-18: —CO—O—divalent chain group —O—CO—O—divalent cyclic group —O—CO—
L-19: —CO—O—divalent chain group—O—CO—O—divalent cyclic group—divalent chain group—
L-20: —CO—O—divalent chain group—O—CO—O—divalent cyclic group—divalent chain group—CO—O—
L-21: —CO—O—divalent chain group—O—CO—O—divalent cyclic group—divalent chain group—O—CO—

The divalent chain group means an alkylene group, a substituted alkylene group, an alkenylene group, a substituted alkenylene group, an alkynylene group, or a substituted alkynylene group. An alkylene group, a substituted alkylene group, an alkenylene group and a substituted alkenylene group are preferred, and an alkylene group and an alkenylene group are more preferred.
The alkylene group may have a branch. The alkylene group preferably has 1 to 12 carbon atoms, more preferably 2 to 10 carbon atoms, and most preferably 2 to 8 carbon atoms.
The alkylene part of the substituted alkylene group is the same as the above alkylene group. Examples of the substituent include a halogen atom.
The alkenylene group may have a branch. The alkenylene group preferably has 2 to 12 carbon atoms, more preferably 2 to 10 carbon atoms, and most preferably 2 to 8 carbon atoms.
The alkylene part of the substituted alkylene group is the same as the above alkylene group. Examples of the substituent include a halogen atom.
The alkynylene group may have a branch. The alkynylene group preferably has 2 to 12 carbon atoms, more preferably 2 to 10 carbon atoms, and most preferably 2 to 8 carbon atoms.
The alkynylene part of the substituted alkynylene group is the same as the above alkynylene group. Examples of the substituent include a halogen atom.
Specific examples of the divalent chain group include ethylene, trimethylene, propylene, tetramethylene, 2-methyl-tetramethylene, pentamethylene, hexamethylene, octamethylene, 2-butenylene, 2-butynylene and the like.

The definition and examples of the divalent cyclic group are the same as those of Cy ¹ , Cy ² and Cy ³ described later.

In the general formula (1), L ² or L ³ are each independently a single bond or a divalent linking group. L ² and L ³ each independently comprises —O—, —S—, —CO—, —NR—, —C═N—, a divalent chain group, a divalent cyclic group, and combinations thereof. It is preferably a divalent linking group or a single bond selected from the group. R is an alkyl group having 1 to 7 carbon atoms or a hydrogen atom, preferably an alkyl group having 1 to 4 carbon atoms or a hydrogen atom, more preferably a methyl group, an ethyl group or a hydrogen atom. Preferably, it is a hydrogen atom. The divalent chain group and the divalent cyclic group have the same definitions as L ¹ and L ⁴ .
Preferred divalent linking groups as L ² or L ³ include —COO—, —OCO—, —OCOO—, —OCONR—, —COS—, —SCO—, —CONR—, —NRCO—, —CH _2. CH ₂ —, —C═C—COO—, —C═N—, —C═N—N═C—, and the like.

In the general formula (1), n is 0, 1, 2, or 3. When n is 2 or 3, two L ³ may be the same or different, and two Cy ² may be the same or different. n is preferably 1 or 2, and more preferably 1.

In the general formula (1), Cy ¹ , Cy ² and Cy ³ are each independently a divalent cyclic group.
The ring contained in the cyclic group is preferably a 5-membered ring, a 6-membered ring, or a 7-membered ring, more preferably a 5-membered ring or a 6-membered ring, and most preferably a 6-membered ring.
The ring contained in the cyclic group may be a condensed ring. However, it is more preferably a monocycle than a condensed ring.
The ring contained in the cyclic group may be any of an aromatic ring, an aliphatic ring, and a heterocyclic ring. Examples of the aromatic ring include a benzene ring and a naphthalene ring. Examples of the aliphatic ring include a cyclohexane ring. Examples of the heterocyclic ring include a pyridine ring and a pyrimidine ring.
As the cyclic group having a benzene ring, 1,4-phenylene is preferable. As the cyclic group having a naphthalene ring, naphthalene-1,5-diyl and naphthalene-2,6-diyl are preferable. The cyclic group having a cyclohexane ring is preferably 1,4-cyclohexylene. The cyclic group having a pyridine ring is preferably pyridine-2,5-diyl. The cyclic group having a pyrimidine ring is preferably pyrimidine-2,5-diyl.
The cyclic group may have a substituent. Examples of the substituent include a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 5 carbon atoms, a halogen-substituted alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms. An alkylthio group having 1 to 5 carbon atoms, an acyloxy group having 2 to 6 carbon atoms, an alkoxycarbonyl group having 2 to 6 carbon atoms, a carbamoyl group, and an alkyl-substituted carbamoyl group having 2 to 6 carbon atoms And an acylamino group having 2 to 6 carbon atoms.

Examples of the polymerizable rod-like liquid crystal compound represented by the general formula (1) are shown below, but examples of the polymerizable rod-like liquid crystal compound are not limited to these.

In addition to the polymerizable rod-like liquid crystal compound represented by the general formula (1), it is preferable to use at least one compound represented by the following general formula (2) as the rod-like liquid crystal compound.

General formula (2)
M ^1- (L ¹ ) p-Cy ¹ -L ^2- (Cy ² -L ³ ) n-Cy ^3- (L ⁴ ) q-M ²
(In the general formula (2), M ¹ and M ² are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a heterocyclic group, a cyano group, a halogen, —SCN, — CF ₃ , a nitro group, or Q ¹ is represented, but at least one of M ¹ and M ² represents a group other than Q ¹ .
^{However, Q 1, L 1, L} 2, L 3, L 4, Cy 1, Cy 2, Cy 3 and n have the same meanings as the group represented by the general formula (1). P and q are 0 or 1. )

When M ¹ and M ² do not represent Q ¹ , M ¹ and M ² are preferably a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a cyano group, more preferably , An alkyl group having 1 to 4 carbon atoms, or a phenyl group, and p and q are preferably 0.

Moreover, the preferable mixing ratio (mass ratio) of the compound represented by the general formula (2) in the mixture of the polymerizable liquid crystal compound represented by the general formula (1) and the compound represented by the general formula (2). Is 0.1% to 40%, more preferably 1% to 30%, and still more preferably 5% to 20%.

Hereinafter, preferred examples of the compound represented by the general formula (2) are shown, but the present invention is not limited thereto.

The discotic liquid crystal compounds are disclosed in various literatures (C. Destrade et al., Mol. Cryst. Liq. Cryst., Vol. 71, page 111 (1981); edited by The Chemical Society of Japan, Quarterly Chemical Review, No. 22, Liquid Crystal). Chemistry, Chapter 5, Chapter 10 Section 2 (1994); B. Kohne et al., Angew. Chem. Soc. Chem. Comm., Page 1794 (1985): J. Zhang et al., J. Chem. Am. Chem. Soc., Vol. 116, page 2655 (1994)). The polymerization of the discotic liquid crystal compound is described in JP-A-8-27284. In order to fix the discotic alignment layer liquid crystal compound by polymerization, it is necessary to bond a polymerizable group as a substituent to the discotic core of the discotic liquid crystal compound. However, when the polymerizable group is directly connected to the disc-shaped core, it becomes difficult to maintain the orientation state in the polymerization reaction. Therefore, a linking group is introduced between the discotic core and the polymerizable group. That is, the photocurable discotic liquid crystal compound is preferably a compound represented by the following formula (3).

General formula (3)
D (-LP) n
(In the general formula, D is a discotic core, L is a divalent linking group, P is a polymerizable group, and n is an integer of 4 to 12.)
Preferred specific examples of the discotic core (D), the divalent linking group (L), and the polymerizable group (P) in the formula (3) are (D1) to (D1) described in JP-A-2001-4837, respectively. (D15), (L1) to (L25), (P1) to (P18), and the contents described in the publication can be preferably used.
As the discotic liquid crystal compound, it is also preferable to use a compound represented by the general formula (DI) described in JP-A-2007-2220.

The liquid crystal compound is 80% by mass or more, 90% by mass or more, or 95% by mass or more, and 99.99%, based on the solid content mass (the mass excluding the solvent) of the composition for forming the optically anisotropic layer. It should just be contained by the mass% or less, 99.98 mass% or less, and 99.97 mass% or less. In particular, the compound containing an acrylic group or a methacryl group is 70% by mass or more, 80% by mass or more, 90% by mass or more, or 95% by mass or more, and 99.99% by mass or less, 99.98% by mass or less. 99.97% by mass or less.

The liquid crystal compound may be fixed in any alignment state of horizontal alignment, vertical alignment, tilt alignment, and twist alignment. In this specification, “horizontal alignment” means that in the case of a rod-like liquid crystal, the molecular long axis and the horizontal plane of the transparent support are parallel, and in the case of a disc-like liquid crystal, the disc surface of the core of the disc-like liquid crystal compound. And the horizontal plane of the transparent support is parallel, but it is not required to be strictly parallel, and in this specification, an inclination angle with the horizontal plane is less than 10 degrees. To do. The optically anisotropic layer used in the present invention preferably contains a rod-shaped liquid crystal compound fixed in a horizontally aligned state.

[solvent]
As a solvent used for preparing a coating liquid when a composition containing a liquid crystal compound is prepared as a coating liquid, an organic solvent, water, or a mixed solvent thereof is preferably used. Examples of organic solvents include amides (eg N, N-dimethylformamide), sulfoxides (eg dimethyl sulfoxide), heterocyclic compounds (eg pyridine), hydrocarbons (eg benzene, hexane), alkyl halides (eg , Chloroform, dichloromethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone), ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane), alkyl alcohols (eg, , Methanol, ethanol, propanol). Two or more kinds of solvents may be mixed and used. Among the above, alkyl halides, esters, ketones and mixed solvents thereof are preferable.

[Fixed orientation]
The alignment of the liquid crystalline compound is preferably fixed by a crosslinking reaction of a polymerizable group introduced into the liquid crystalline compound, more preferably by a polymerization reaction of the polymerizable group. The polymerization reaction includes a thermal polymerization reaction using a thermal polymerization initiator and a photopolymerization reaction using a photopolymerization initiator. The polymerization reaction may be either radical polymerization or cationic polymerization, but radical polymerization is preferred.
Examples of radical photopolymerization initiators include α-carbonyl compounds (described in US Pat. Nos. 2,367,661 and 2,367,670), acyloin ether (described in US Pat. No. 2,448,828), α-hydrocarbon-substituted aromatics. An acyloin compound (described in US Pat. No. 2,722,512), a polynuclear quinone compound (described in US Pat. Nos. 3,046,127 and 2,951,758), a combination of a triarylimidazole dimer and p-aminophenyl ketone (US Pat. No. 3,549,367) Acridine and phenazine compounds (JP-A-60-105667, US Pat. No. 4,239,850) and oxadiazole compounds (US Pat. No. 4,212,970). Examples of the cationic photopolymerization initiator include organic sulfonium salt systems, iodonium salt systems, phosphonium salt systems, and the like. Organic sulfonium salt systems are preferable, and triphenylsulfonium salts are particularly preferable. As counter ions of these compounds, hexafluoroantimonate, hexafluorophosphate, and the like are preferably used.

A radical thermal polymerization initiator is a compound that generates radicals when heated to a decomposition temperature or higher. Examples of such radical thermal polymerization initiator include diacyl peroxide (acetyl peroxide, benzoyl peroxide, etc.), ketone peroxide (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), hydroperoxide (hydrogen peroxide, tert -Butyl hydroperoxide, cumene hydroperoxide, etc.), dialkyl peroxides (di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc.), peroxyesters (tert-butyl peroxyacetate, tert -Butyl peroxypivalate, etc.), azo compounds (azobisisobutyronitrile, azobisisovaleronitrile, etc.), persulfates (ammonium persulfate, sodium persulfate, persulfate) Potassium, etc.) and the like.

The amount of the polymerization initiator used is preferably 0.01 to 20% by mass, more preferably 0.5 to 5% by mass, based on the solid content of the coating solution. Light irradiation for photopolymerization of the liquid crystal compound is preferably performed using ultraviolet rays. The irradiation energy is preferably 10 mJ / cm ² to 10 J / cm ² , and more preferably 25 to 1000 mJ / cm ² . The illuminance is preferably 10 to 2000 mW / cm ² , more preferably 20 to 1500 mW / cm ² , and still more preferably 40 to 1000 mW / cm ² . The irradiation wavelength preferably has a peak at 250 to 450 nm, and more preferably has a peak at 300 to 410 nm. In order to accelerate the photopolymerization reaction, light irradiation may be performed under an inert gas atmosphere such as nitrogen or under heating conditions.
Heating for thermal polymerization of the liquid crystal compound is preferably performed within a temperature range of 50 to 200 ° C. for 10 minutes to 30 hours.

[Horizontal alignment agent]
In the composition containing the liquid crystal compound, the compounds represented by the general formulas (1) to (3) and the general formula (4) described in paragraphs “0098” to “0105” of JP-A-2009-69793 By containing at least one fluorine-containing homopolymer or copolymer using a monomer, the molecules of the liquid crystal compound can be horizontally aligned. When the liquid crystal compound is horizontally aligned, the inclination angle is preferably 0 to 5 degrees, more preferably 0 to 3 degrees, further preferably 0 to 2 degrees, and most preferably 0 to 1 degree.

The addition amount of the horizontal alignment agent is preferably 0.01 to 20% by mass, more preferably 0.01 to 10% by mass, and particularly preferably 0.02 to 1% by mass, based on the mass of the liquid crystal compound. The compounds represented by the general formulas (1) to (4) described in paragraphs “0098” to “0105” of JP-A-2009-69793 may be used alone or in combination of two or more. You may use together.

[Other additives]
A composition containing a liquid crystal compound contains an onium salt described in paragraphs 0121 to 0148 of JP2013-050583A, particularly a pyridinium compound represented by formula (I) described in JP2006-113500A. May be. The onium salt can function as an alignment layer interface side vertical alignment agent. For example, the molecules of the discotic liquid crystalline compound can be aligned vertically in the vicinity of the alignment layer. The composition containing a liquid crystal compound may contain a boronic acid compound represented by the general formula (I) described in JP2013-0542201A.
The composition containing a liquid crystal compound may contain other necessary additives, but preferably does not contain a so-called chiral agent.

[Coating method]
Application of the composition during the formation of the optically anisotropic layer includes dip coating, air knife coating, spin coating, slit coating, curtain coating, roller coating, wire bar coating, gravure coating, The extrusion coating method (US Pat. No. 2,681,294) can be used. Two or more layers may be applied simultaneously. The methods of simultaneous application are described in US Pat. Nos. 2,761,791, 2,941,898, 3,508,947, and 3,526,528 and Yuji Harasaki, Coating Engineering, page 253, Asakura Shoten (1973).

[Temporary support]
The temporary support is not particularly limited and may be rigid or flexible, but is preferably flexible in terms of easy handling. The rigid support is not particularly limited, but is a known glass plate such as a soda glass plate having a silicon oxide film on its surface, a low expansion glass, a non-alkali glass, a quartz glass plate, a metal such as an aluminum plate, an iron plate, or a SUS plate. A board, a resin board, a ceramic board, a stone board, etc. are mentioned. There are no particular limitations on the flexible support, but cellulose esters (eg, cellulose acetate, cellulose propionate, cellulose butyrate), polyolefins (eg, norbornene polymers), poly (meth) acrylic acid esters (eg, polymethyl) Methacrylate), polycarbonate, polyester (eg, polyethylene terephthalate or polyethylene naphthalate), polysulfone, and cycloolefin polymer (eg, norbornene resin (ZEONEX, ZEONOR, manufactured by Nippon Zeon Co., Ltd., Arton manufactured by JSR), etc.) ) And other plastic films, paper, aluminum foil, and cloth. Among these, polyethylene terephthalate (PET) is more preferable. In view of ease of handling, the thickness of the rigid support is preferably from 100 to 3000 μm, and more preferably from 300 to 1500 μm. The film thickness of the flexible support may be about 5 μm to 1000 μm, preferably 10 μm to 250 μm, more preferably 15 μm to 90 μm.

In the course of research by the present inventors, it was found that a thin film polarizing plate including a hard coat layer is likely to curl. In particular, the polarizing plate may curl so that the hard coat layer side is recessed with respect to the polarizer. Such curling is not preferable when a polarizing plate is laminated on another film by a procedure such as roll-to-roll. The present inventors have found that such curling does not occur when the temporary support is not peeled after the transfer material is adhered to the film containing the polarizer on the surface of the optically anisotropic layer. Therefore, the polarizing plate of the present invention is transported or the like in a configuration including a temporary support, and is cut into an appropriate size immediately before mounting on a display device, or a temporary support is newly applied to the release surface immediately after peeling. It is also preferable to provide an adhesive layer or a separate film.

[Alignment layer]
An alignment layer may be used for forming the optically anisotropic layer. The alignment layer may be provided on the surface of the temporary support or an undercoat layer (may be an optically anisotropic layer) coated on the temporary support. The alignment layer functions to define the alignment of the liquid crystal compound in the composition provided thereon. The orientation layer may be any layer as long as it can impart orientation to the optically anisotropic layer. Not only a known material for the vertical alignment film but also a known material for the horizontal alignment film can be selected. Examples of the alignment layer include a layer made of an organic compound (preferably a polymer), a photo-alignment layer that exhibits liquid crystal alignment by polarized irradiation represented by azobenzene polymer and polyvinyl cinnamate, an oblique deposition layer of an inorganic compound, And a layer having a microgroove, a cumulative film formed by Langmuir-Blodgett method (LB film) such as ω-tricosanoic acid, dioctadecylmethylammonium chloride and methyl stearylate, or a dielectric by applying an electric field or a magnetic field. Mention may be made of oriented layers. As the alignment layer, a polymer layer is preferable, and a polymer layer containing modified or unmodified polyvinyl alcohol is particularly preferable. Modified or unmodified polyvinyl alcohol is also used as a horizontal alignment film, but by adding an onium compound to the composition for forming an optically anisotropic layer, the action of the onium compound and the alignment film, and the onium compound The liquid crystal molecules can be aligned in a tilted alignment state with a high average tilt angle or in a vertical alignment state at the interface of the alignment film by the action of the liquid crystal compound and the liquid crystal compound. Modified polyvinyl alcohol is a product in which at least one hydroxyl group of polyvinyl alcohol is modified with a functional group. For example, polyvinyl alcohol is modified with an acetoacetyl group, a sulfonic acid group, a carboxyl group, an oxyalkylene group, or the like. including. As the alignment film, it is preferable to use an alignment film containing a modified polyvinyl alcohol containing a unit having a polymerizable group. This is because the adhesion with the optically anisotropic layer can be further improved. Further, polyvinyl alcohol in which at least one hydroxyl group is substituted with a group having a vinyl moiety, an oxiranyl moiety or an aziridinyl moiety is preferable. For example, modified polyvinyl alcohol described in paragraph Nos. [0071] to [0095] of Japanese Patent No. 3907735 Alcohol is preferred.
The thickness of the alignment layer is preferably 0.01 to 5 μm, more preferably 0.05 to 2 μm.

[Rubbing]
The rubbing treatment is preferably performed on the surface of the alignment layer, the temporary support, the optically anisotropic layer, or the like. The rubbing treatment applied to the alignment layer can be generally carried out by rubbing the surface of the film mainly composed of a polymer with paper or cloth in a certain direction. A general method of rubbing is described in, for example, “Liquid Crystal Handbook” (issued by Maruzen, October 30, 2000).

As a method for changing the rubbing density, a method described in “Liquid Crystal Handbook” (published by Maruzen) can be used. The rubbing density (L) is quantified by the following formula (A).
Formula (A) L = Nl (1 + 2πrn / 60v)
In the formula (A), N is the number of rubbing, l is the contact length of the rubbing roller, r is the radius of the roller, n is the number of rotations (rpm) of the roller, and v is the stage moving speed (second speed).

In order to increase the rubbing density, the rubbing frequency should be increased, the contact length of the rubbing roller should be increased, the radius of the roller should be increased, the rotation speed of the roller should be increased, and the stage moving speed should be decreased, while the rubbing density should be decreased. To do this, you can reverse this.
In addition, the description in Japanese Patent No. 4052558 can also be referred to as conditions for the rubbing process.

[Hard coat layer]
The polarizing plate of the present invention includes a hard coat layer. The hard coat layer should just be contained in the surface side opposite to the side in which the optically anisotropic layer is provided with respect to the polarizer. The hard coat layer may be included as the outermost layer of the polarizing plate, and another layer may be provided outside the hard coat layer.
In the present specification, the hard coat layer refers to a layer that, when formed, increases the pencil hardness of the polarizing plate. Specifically, it is a layer having a pencil hardness (JIS K5400) of H or higher after the hard coat layer lamination. The pencil hardness after laminating the hard coat layer is preferably 2H or more, and more preferably 3H or more. The thickness of the hard coat layer is preferably 0.4 to 35 μm, more preferably 1 to 30 μm, and most preferably 1.5 to 20 μm.

A polarizing plate, particularly a front side polarizing plate of a liquid crystal display device or a polarizing plate of an organic EL display device, has physical strength (such as scratch resistance), transparency, chemical resistance, and weather resistance (such as moisture and heat resistance). Required. Further, in order to prevent a decrease in contrast due to reflection of external light or reflection of an image, antiglare performance and antireflection performance are required. The hard coat layer can be provided for imparting such performance to the surface of the polarizing plate.

Specific examples of the hard coat layer are formed from a composition containing particles and an ultraviolet curable resin, which is described as a hard coat layer in JP2012-103690A and an antiglare layer in JP2012-185290A. Layer. As described in JP 2012-103689 A, a plurality of layers having different refractive indexes may be further laminated on the hard coat layer to form an antireflection layer.

(Transparent support)
The hard coat layer is preferably formed from a composition coated on the transparent support surface. In this specification, transparent means that the transmittance of visible light is 60% or more, preferably 80% or more, and particularly preferably 90% or more. Examples of transparent support materials include cellulose acylate polymers represented by triacetyl cellulose, polycarbonate polymers, polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, and (meth) acrylic polymers such as polymethyl methacrylate. Examples thereof include polymers and styrene polymers such as polystyrene and acrylonitrile / styrene copolymer (AS resin). Polyolefins such as polyethylene and polypropylene, polyolefin polymers such as ethylene / propylene copolymers, vinyl chloride polymers, amide polymers such as nylon and aromatic polyamide, imide polymers, sulfone polymers, polyethersulfone polymers , Polyether ether ketone polymer, polyphenylene sulfide polymer, vinylidene chloride polymer, vinyl alcohol polymer, vinyl butyral polymer, arylate polymer, polyoxymethylene polymer, epoxy polymer, or polymer mixed examples As mentioned.
As a material for forming the transparent support, a thermoplastic norbornene resin can be preferably used. Examples of the thermoplastic norbornene-based resin include ZEONEX, ZEONOR manufactured by Nippon Zeon Co., Ltd., and ARTON manufactured by JSR Corporation.
The transparent support only needs to contain one or more of the above polymers as a main component, for example, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, 99% by mass or more, or 100 mass% should just be included.
The film thickness of the transparent support may be 1 μm to 200 μm, and is preferably 5 μm to 100 μm.

[Polarizer]
Examples of the polarizer include an iodine polarizer, a dye polarizer using a dichroic dye, and a polyene polarizer. The iodine-based polarizer and the dye-based polarizer are generally produced using a polyvinyl alcohol film. In the present invention, any polarizer may be used. For example, the polarizer is preferably composed of modified or unmodified polyvinyl alcohol and a dichroic molecule. For a polarizer composed of modified or unmodified polyvinyl alcohol and a dichroic molecule, reference can be made to, for example, the description in JP-A-2009-237376. The film thickness of a polarizer should just be 50 micrometers or less, 30 micrometers or less are preferable and 20 micrometers or less are more preferable. Moreover, the film thickness of a polarizer should just normally be 1 micrometer or more, 5 micrometers or more, or 10 micrometers or more.

[Film including polarizer]
The film including the polarizer to which the transfer body is adhered may be composed of only the polarizer, and may include other layers such as a protective layer in addition to the polarizer.

[Protective layer (protective film)]
The polarizing plate may contain a protective layer. For example, a protective layer may be provided on one or both surfaces of the polarizer to form a film containing the above polarizer. Further, in the transfer material, a protective layer may be provided in advance, preferably on the outermost surface opposite to the temporary support side when viewed from the optically anisotropic layer. Alternatively, after the transfer material or transfer body and a film containing a polarizer are bonded, a protective layer may be provided on one or both surfaces.
The protective layer may be provided so as to be in direct contact with other layers, for example, by directly applying and drying the protective layer forming composition on the surface on which the protective layer is provided, but usually using an adhesive. , It may be adhered to the surface. Examples of the adhesive or the pressure-sensitive adhesive include the same adhesives used for bonding the transfer material and the film containing the polarizer.

As the protective layer, a cellulose acylate polymer film, an acrylic polymer film ((meth) acrylic polymer film), or a cycloolefin polymer film can be used. Regarding the cellulose acylate polymer, reference can be made to the description of the cellulose acylate resin in JP2011-237474A. As for the cycloolefin-based polymer film, the descriptions in JP2009-175222A and JP2009-237376A can be referred to. By including the cycloolefin polymer film, moisture permeability can be imparted to the polarizing plate. Moisture permeable means the property that water does not pass but water vapor passes.
The protective layer only needs to contain one or more of the above polymers as a main component, for example, 70 mass% or more, 80 mass% or more, 90 mass% or more, 95 mass% or more, 99 mass% or more, or 100 mass% should just be included.
The film thickness of the protective layer may be 100 μm or less, 50 μm or less, 30 μm or less, 20 μm or less, 10 μm or less, and may be 1 μm or more, 5 μm or more, and 10 μm or more.

[Adhesive layer]
In the polarizing plate of this invention, the optically anisotropic layer is provided through the contact bonding layer on the single side | surface side of the film containing a polarizer. Although the hard coat layer is provided on the other surface side, the hard coat layer may be provided via an adhesive layer. When the hard coat layer on the transparent support is adhered, it is preferably adhered on the surface on the transparent support side, and more preferably, the transparent support and the polarizer are directly adhered. In the present specification, an adhesive layer that adheres a film containing a polarizer and an optically anisotropic layer (transfer material or transfer body) is an adhesive layer 1, and an adhesive layer that adheres a film containing a polarizer and a hard coat layer. Is sometimes referred to as an adhesive layer 2.

The adhesive layer may be formed from an adhesive. In this specification, “adhesion” is used in a concept including “adhesion”. The adhesive is not particularly limited, but a polyvinyl alcohol adhesive, a boron compound aqueous solution, an epoxy compound curable adhesive that does not contain an aromatic ring in the molecule, as disclosed in JP-A-2004-245925, JP-A-2008-174667, an active energy ray curable adhesive comprising a photopolymerization initiator having a molar extinction coefficient of 400 or more at a wavelength of 360 to 450 nm and an ultraviolet curable compound as essential components, and JP2008-174667A (A) a (meth) acrylic compound having 2 or more (meth) acryloyl groups in the molecule, and (b) a hydroxyl group in the molecule A (meth) acrylic compound having only one polymerizable double bond, and (c) a phenol ethylene oxide-modified acrelain Or the like active energy ray-curable adhesive agents containing a nonylphenol ethylene oxide modified acrylate.

The polyvinyl alcohol-based adhesive is an adhesive containing modified or unmodified polyvinyl alcohol. The polyvinyl alcohol-based adhesive may contain a crosslinking agent in addition to the modified or unmodified polyvinyl alcohol. Specific examples of the adhesive include an aqueous solution of polyvinyl alcohol or polyvinyl acetal (eg, polyvinyl butyral) and a latex of a vinyl polymer (eg, polyvinyl chloride, polyvinyl acetate, polybutyl acrylate). A particularly preferable adhesive is an aqueous solution of polyvinyl alcohol. At this time, the polyvinyl alcohol is preferably completely saponified.

Among these, polyvinyl alcohol adhesives and active energy ray curable adhesives are preferable.
The adhesive layer 1 and the adhesive layer 2 may be made of the same material or different.
The thickness of the adhesive layer is preferably 0.01 to 10 μm, particularly preferably 0.05 to 5 μm in terms of dry film thickness for both the adhesive layer 1 and the adhesive layer 2.

[Other functional layers]
In addition to the above layers, the polarizing plate may include other functional layers such as a low moisture-permeable layer, an antistatic layer, a release layer, and a release layer.
(Release layer)
The release layer is a layer that is provided between the temporary support and the transfer body, and is peeled from the transfer material together with the temporary support when the temporary support is peeled off in the manufacturing process of the polarizing plate. By using the release layer, the separation between the temporary support and the transfer body is stabilized, and the transferability during transfer can be improved.

As the release layer, a release resin, a resin containing a release agent, a curable resin that is cross-linked by light irradiation, and the like can be applied. Examples of the release resin include fluorine-based resins, silicones, melamine-based resins, epoxy resins, polyester resins, acrylic resins, and fiber-based resins, and preferably melamine-based resins. Examples of the resin containing a release agent include acrylic resins, vinyl resins, polyester resins, and fiber resins obtained by adding or copolymerizing release agents such as fluorine resins, silicones, and various waxes. Can be mentioned.

The release layer may be formed by dispersing or dissolving the resin in a solvent, and applying and drying by a known coating method such as roll coating or gravure coating. If necessary, it may be crosslinked by heating at a temperature of 30 ° C. to 120 ° C., aging, or irradiation with ionizing radiation. The thickness of the release layer is usually about 0.01 μm to 5.0 μm, preferably about 0.5 μm to 3.0 μm.

(Peeling layer)
The release layer is provided between the temporary support and the transfer body. When the temporary support is released in the manufacturing process of the polarizing plate of the present invention, the transfer body obtained by peeling the temporary support from the transfer material. It is the layer which becomes the outermost surface of Use of the release layer stabilizes the temporary support from the transfer material.
Since the release layer is the outermost surface of the transfer body, it preferably has surface protection.
As a material for the release layer, it has peelability from the temporary support and adhesion to adjacent layers (alignment layer, optically anisotropic layer, etc.) formed on the opposite side of the temporary support as viewed from the release layer. Is not particularly limited, for example, acrylic resin, vinyl chloride-vinyl acetate copolymer resin, polyester resin, polymethacrylate resin, polyvinyl chloride resin, cellulose resin, silicone resin, chlorinated rubber, casein, A metal oxide or the like can be used. These may be used in combination of two or more. In addition, release agents such as fluorine resins, silicones, various waxes, various surfactants, and the like may be added or copolymerized.
In the transfer material, it is also preferable that the optically anisotropic layer or the alignment layer also serves as a release layer.

[Production Method of Polarizing Plate]
In the polarizing plate of the present invention, the optically anisotropic layer in the transfer material is laminated on one side of the film containing the polarizer, and the hard coat layer is laminated on the other side of the film containing the polarizer. Can be manufactured. Any lamination may be performed first. For the lamination of the optically anisotropic layer on one side of the film containing the polarizer, the transfer material is bonded to the temporary support so that the surface on the optically anisotropic layer side is on the polarizer side or transferred. What is necessary is just to adhere | attach the transfer body which peeled the temporary support body from material to the film containing a polarizer. The surface of the transfer body to be adhered to the film containing the polarizer may be any surface such as an optically anisotropic layer, an alignment layer, and a release layer.
You may peel a temporary support body after adhesion | attachment of the transfer material to the film containing a polarizer.
The method for peeling the temporary support is not particularly limited. The temporary support is preferably peeled at a speed that does not cause damage to the transfer body.

When the prepared transfer material is larger than the produced polarizing plate, the transfer material may be cut before peeling off the temporary support. For example, cutting the transfer material made in the width 1.5m or more rolled, 0.1 m ² or less, 0.05 m ² or less, 0.03 m ² or less, 0.025 m ² or less, 0.02 m ² or less, 0.01 m ² or less, 0.005 m ² or less, or 0.003m ² or less order of magnitude, may be cut into any shape, such as square or rectangular. The lower limit of the shape is not particularly limited, and may be a size that can be handled according to the purpose, but may be usually about 0.0001 m ² (1 cm ² ) or more.

The outermost surface of the transfer material or the transfer body at the time of adhesion may be adhered to the polarizer in the film containing the polarizer or may be adhered to a layer other than the polarizer, but is preferably adhered to the polarizer. The hard coat layer may be adhered to the polarizer in the film containing the polarizer or may be adhered to a layer other than the polarizer, but is preferably adhered to the polarizer. In particular, the hard coat layer is preferably bonded to a film containing a polarizer together with a transparent support adjacent to the hard coat layer, and the transparent support and the polarizer are preferably directly bonded. Bonding may be performed with the above-described adhesive. When adhering the transfer material or transfer body to a film containing a polarizer, and using an active energy ray-curable adhesive, the active energy ray such as ultraviolet rays is irradiated to the polarizer from the optical anisotropy side. The adhesive can be cured to form an adhesive layer. When directly bonding the optical anisotropy and the polarizer, it is preferable to use an active energy ray-curable adhesive.

The present invention will be described more specifically with reference to the following examples. The materials, reagents, amounts and ratios of substances, operations, and the like shown in the following examples can be appropriately changed without departing from the gist of the present invention. Therefore, the scope of the present invention is not limited to the following examples.

[Manufacture of transfer materials]
(Formation of alignment layer)
Fujifilm PET (thickness 75 μm) was prepared as a temporary support, and an alignment layer coating solution having the following composition was continuously applied with a # 14 wire bar. Drying was performed with warm air of 60 ° C. for 60 seconds, and further with warm air of 100 ° C. for 120 seconds. The degree of saponification of the modified polyvinyl alcohol used was 96.8%. The thickness of the obtained alignment film was 0.5 μm.
――――――――――――――――――――――――――――――――――
Composition of coating solution for alignment layer ――――――――――――――――――――――――――――――――――
Modified polyvinyl alcohol (A) 10 parts by weight Water 308 parts by weight Methanol 70 parts by weight Isopropanol 29 parts by weight Photopolymerization initiator (Irgacure 2959, manufactured by BASF) 0.8 parts by weight ――――――――――― ―――――――――――――――――――――――

(Preparation of optically anisotropic layer 1 with alignment layer)
The coating liquid shown below was apply | coated to the rubbing surface of the said orientation layer which carried out the rubbing process by the extrusion application | coating on the said orientation layer (with a temporary support body). Then, after drying at room temperature for 30 seconds, heating for 2 minutes in an atmosphere at 90 ° C., and then UV irradiation with a fusion D bulb (lamp 90 mW / cm) at an output of 60% for 6 to 12 seconds, optically anisotropic A conductive layer was prepared. Application was performed so that the film thickness of the optically anisotropic layer was 3.0 μm. The average inclination angle with respect to the film surface of the rod-shaped liquid crystal compound was 0 °, and it was confirmed that the rod-shaped liquid crystal compound was aligned horizontally with respect to the film surface.

[Preparation of polarizing plate 1 with temporary support]
(Production of polarizer)
A roll-like polyvinyl alcohol film having a thickness of 80 μm was continuously stretched 5 times in an aqueous iodine solution and dried to obtain a polarizing film (polarizer) having a thickness of 20 μm.

(Preparation of coating solution for antiglare layer)
Each component was mixed with a mixed solvent (89 to 11 (mass ratio)) of MIBK (methyl isobutyl ketone) and MEK (methyl ethyl ketone) so as to have the following composition. It filtered with the polypropylene filter with the hole diameter of 30 micrometers, and prepared the coating liquid 1 for glare-proof layers. The solid concentration of each coating solution is 40% by mass. In preparing the coating solution, the resin particles and smectite were added in the state of a dispersion described later.

――――――――――――――――――――――――――――――――――
Antiglare layer coating solution 1
――――――――――――――――――――――――――――――――――
Smectite (Lucentite STN, manufactured by Corp Chemical)
1.00% by mass
Resin particles (Techpolymer SSX, manufactured by Sekisui Plastics Co., Ltd.) 8.00% by mass
Acrylate monomer (NK ester A9550, manufactured by Shin-Nakamura Chemical Co., Ltd.)
87.79% by mass
Polymerization initiator (Irgacure 907, manufactured by BASF) 3.00% by mass
Leveling agent (P-4) 0.15% by mass
Dispersant (DISPERBYK-2164, manufactured by Big Chemie Japan)
0.06 mass%
――――――――――――――――――――――――――――――――――

(Preparation of resin particle dispersion)
The dispersion of translucent resin particles is gradually added to the stirred MIBK solution until translucent resin particles (Techpolymer SSX, manufactured by Sekisui Kasei Co., Ltd.) reach a solid content concentration of 30% by mass. For 30 minutes.

(Preparation of smectite dispersion)
As the smectite dispersion, all MEKs used in the coating solution for the antiglare layer are finally added. While stirring, the smectite (Lucentite STN, manufactured by Corp Chemical Co.) is gradually added and stirred for 30 minutes. Prepared.

[Preparation of transparent support with antiglare layer]
(Coating of antiglare layer)
A commercially available cellulose acylate film (Fujitack ZRD40, manufactured by Fuji Film Co., Ltd., film thickness 40 μm) is unwound in a roll form, and the antiglare layer is used so as to have a film thickness of 4 μm using the coating solution 1 for the antiglare layer. Was applied.
Specifically, in the die coating method using the slot die described in Example 1 of Japanese Patent Application Laid-Open No. 2006-122889, each coating solution is applied at a conveyance speed of 30 m / min, and dried at 80 ° C. for 150 seconds. Further, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) having an oxygen concentration of about 0.1% under a nitrogen purge, it is applied by irradiating ultraviolet rays with an illuminance of 400 mW / cm ² and an irradiation amount of 180 mJ / cm ^2. After the layer was cured to form an antiglare layer, it was wound up to produce a transparent support with an antiglare layer.

The transparent support with an antiglare layer was immersed in a 1.5 mol / L NaOH aqueous solution (saponification solution) maintained at 55 ° C. for 2 minutes, and then the film was washed with water, and then a 0.05 mol / L sulfuric acid aqueous solution at 25 ° C. Then, the film was neutralized by passing a washing bath under running water for 30 seconds. Then, draining with an air knife was repeated three times, and after dropping the water, the film was retained in a drying zone at 70 ° C. for 15 seconds and dried to produce a saponified film.

The thus obtained saponified transparent support with an antiglare layer was bonded to a cellulose acylate film side with a 3% aqueous solution of PVA (manufactured by Kuraray Co., Ltd., PVA-117H) as an adhesive. The polarizer was bonded so that the longitudinal direction of the roll of the polarizer and the longitudinal direction of the roll of the transparent support with antiglare layer were parallel to each other.

The optically anisotropic layer 1 with an orientation layer on the temporary support prepared above is disposed on the surface different from the surface provided with the transparent support with an antiglare layer of the polarizer. Glued on the side. Adhesion is provided by applying a commercially available acrylic adhesive (UV-3300, manufactured by Toagosei Co., Ltd.), and using a 160 W / cm air-cooled metal halide lamp (made by Eye Graphics) from the temporary support side, the irradiation amount is 100 mJ / cm. ^This was carried out by irradiating the ultraviolet ray ² to cure the adhesive, thereby obtaining a polarizing plate 1 with a temporary support having a film thickness of 144.5 μm.

The obtained polarizing plate 1 with a temporary support was successfully transported without wrinkles and could be wound up. In addition, it was found that it can be handled well after lapse of time after winding and is excellent in workability.

The optically anisotropic layer 1 with an orientation layer on the temporary support prepared above is bonded to the polarizer on the surface side of the optically anisotropic layer 1 after peeling the temporary support from the optically anisotropic layer 1. Was produced in the same manner as the polarizing plate 1 with a temporary support, and a polarizing plate 2 having a thickness of 70.5 μm was produced. The obtained polarizing plate 2 was greatly curled to the antiglare layer side, and wrinkles were generated during conveyance and during winding.

DESCRIPTION OF SYMBOLS 1 Polarizer 2 Optically anisotropic layer 4 Protective layer 5 Hard coat layer 6 Transparent support 12 Orientation layer 16 Temporary support 21 Adhesive layer 1
22 Adhesive layer 2

Claims (14)

1. A polarizing plate,
   Including an optically anisotropic layer, a polarizer, and a hard coat layer in this order,
   The optically anisotropic layer is a layer formed from a composition containing a liquid crystal compound,
   A polarizing plate comprising only the adhesive layer 1 or only the protective layer provided on the surface of the adhesive layer 1 and the polarizer between the optically anisotropic layer and the polarizer.
2. The polarizing plate according to claim 1, comprising a transparent support between the polarizer and the hard coat layer, wherein the hard coat layer is in direct contact with the transparent support.
3. The polarizing plate according to claim 2, wherein the transparent support comprises cellulose acylate, (meth) acrylic polymer, cycloolefin polymer, or polyester.
4. The polarizing plate according to claim 2 or 3, comprising only an adhesive layer 2 between the transparent support and the polarizer.
5. The polarizing plate according to any one of claims 1 to 4, wherein the adhesive layer 1 is a layer formed of an active energy ray-curable adhesive.
6. 6. The polarizing plate according to claim 1, wherein the optically anisotropic layer has a thickness of 0.5 μm to 3 μm.
7. The polarizing plate according to any one of claims 1 to 6, comprising only an adhesive layer 1 between the optically anisotropic layer and the polarizer.
8. Only the adhesive layer 1 and a protective layer provided on the surface of the polarizer are included between the optically anisotropic layer and the polarizer, and the protective layer is made of cellulose acylate, (meth) acrylic polymer, or cyclo The polarizing plate according to any one of claims 1 to 7, comprising an olefin polymer.
9. Including a temporary support,
   The optically anisotropic layer is a layer formed from a composition containing a liquid crystal compound applied directly on the surface of the temporary support or directly on an alignment layer provided on the temporary support. The polarizing plate as described in any one of 8.
10. A method for producing a polarizing plate according to any one of claims 1 to 8,
    (1) Prepare the following transfer materials:
    Including a temporary support and an optically anisotropic layer,
    The temporary support has a rubbed surface, or an orientation layer is provided on the surface,
    The optically anisotropic layer is a transfer material that is a layer formed from a composition containing a liquid crystal compound directly applied to the rubbing-treated surface or the alignment layer,
    (2) Laminating the optically anisotropic layer on a film containing a polarizer and adhering it directly or via another layer;
    (3) Laminating a hard coat layer on the surface of the film containing the polarizer opposite to the surface to which the transfer material is adhered; and (4) peeling the temporary support and the optically anisotropic layer. Separating the manufacturing method.
11. In (2), the transfer material is directly bonded to the film containing the polarizer such that the surface on the optically anisotropic layer side is the film side containing the polarizer with respect to the temporary support, And,
    The manufacturing method according to claim 10, wherein (2) and (4) are performed in this order.
12. It is a manufacturing method of the polarizing plate according to claim 9,
    (1) Prepare the following transfer materials:
    Including a temporary support and an optically anisotropic layer,
    The temporary support has a rubbed surface, or an orientation layer is provided on the surface,
    The optically anisotropic layer is a transfer material that is a layer formed from a composition containing a liquid crystal compound directly applied to the rubbing-treated surface or the alignment layer,
    (12) The transfer material is directly adhered to a film containing a polarizer such that the surface on the optically anisotropic layer side is on the film side containing the polarizer, with respect to the temporary support. (3) The manufacturing method including laminating | stacking a hard-coat layer on the surface on the opposite side to the surface which adhere | attaches the said transfer material of the film containing the said polarizer.
13. (2) or (12) is bonded to the polarizer of a laminate obtained by laminating the transfer material on a film containing the polarizer using an active energy ray-curable adhesive. The production method according to any one of claims 10 to 12, which is carried out by irradiating active energy rays from the surface on the anisotropic layer side.
14. The production method according to any one of claims 10 to 13, wherein the polarizer in the film containing the polarizer and the optically anisotropic layer are directly bonded.

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