TW201520612A - Polarizing plate and production method of 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 method of manufacturing a polarizing plate and a polarizing plate. The present invention relates in particular to a polarizing plate having an optically anisotropic layer and a hard coat layer formed of a composition containing a liquid crystal compound, and a method for producing the same.

Due to the expansion of markets such as smart phones or tablet PCs, displays are also becoming thinner. In this trend, thinning is also required in terms of a retardation film used for compensating the viewing angle of the liquid crystal display device. An example in which a film having a predetermined retardation is used as a protective film of a polarizing plate and a phase difference is realized by alignment of a liquid crystal compound is known (for example, Patent Documents 1 and 2), but photohardening using a composition containing a liquid crystal compound is used. Since the optically anisotropic layer formed by the above is low in self-supporting property, it is usually formed on a support such as a deuterated cellulose-based polymer film and used in such a state, and the optically anisotropic layer must be thinned. Review in the form of a support. On the other hand, Patent Document 3 discloses that a composition containing a liquid crystal compound is directly applied to the surface of the polarizing film to form an optically anisotropic layer, and a thin polarizing plate is realized, revealing optical anisotropy on one side of the polarizing film. The specific layer has a specific example of a light diffusion layer formed of a hard coating liquid on the other surface.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2013-050572

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2011-133549

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2004-53770

An object of the present invention is to provide a polarizing plate having a small film thickness. An object of the present invention is to provide a film polarizing plate and a method for producing the same, comprising a polarizing plate comprising an optically anisotropic layer and a hard coat layer formed of a composition containing a liquid crystal compound, wherein the film polarizing plate can be used A method of fabricating an optically anisotropic layer having various optical compensation capabilities and a plurality of polarizers is carried out with a minimum configuration.

The present inventors have intensively studied in order to solve the above problems, and found that an optically anisotropic layer formed on a dummy support is used, and a film polarizing plate having various optical compensation capabilities is not defective in the optical anisotropic layer. of. In addition, this is a need to reduce the thickness of the display, in particular, to reduce the thickness of the small display, and to continuously review the configuration of the polarizing plate suitable for the front polarizing plate or the organic EL display device of the liquid crystal display device. The invention was completed.

That is, the present invention provides the following inventions <1> to <14>.

<1> A polarizing plate comprising an optical anisotropic layer, a polarizing plate, and a hard coat layer in this order, The optically anisotropic layer is a layer formed of a composition containing a liquid crystal compound, and includes only the adhesive layer 1 between the optically anisotropic layer and the polarizer, or only the adhesive layer 1 and the polarizer The protective layer provided on the surface.

<2> The polarizing plate according to <1>, wherein a transparent support is provided between the polarizer and the hard coat layer, and the hard coat layer is directly in contact with the transparent support.

<3> The polarizing plate according to <2>, wherein the transparent support comprises deuterated cellulose, a (meth)acrylic polymer, a cycloolefin polymer, or a polyester.

<4> The polarizing plate according to <2>, wherein the adhesive layer is included only between the transparent support and the polarizer.

The polarizing plate according to any one of <1> to <4> wherein the adhesive layer 1 is a layer formed of an active energy ray-curable adhesive.

The polarizing plate of any one of the above-mentioned optical anisotropic layers, wherein the film thickness of the optically anisotropic layer is 0.5 μm to 3 μm.

The polarizing plate of any one of the above-mentioned optical anisotropic layer and the said polarizer, and the following layer 1 is contained.

The polarizing plate of any one of the above-mentioned optical anisotropic layer and the said polarizer, and only the adhesive layer and the protection provided on the surface of the said polarizer are contained. In the layer, the protective layer comprises deuterated cellulose, a (meth)acrylic polymer, or a cyclic olefin polymer.

The polarizing plate according to any one of <1> to <8> which contains a dummy support, and the optical anisotropic layer is composed of a liquid crystal compound. The object is directly coated on the surface of the dummy support or directly coated on the alignment layer provided on the dummy support.

<10> A method of producing a polarizing plate according to any one of <1> to <8>, wherein the manufacturing method comprises: (1) preparing a transfer material comprising: a dummy support And the optically anisotropic layer, wherein the dummy support has a polished surface, or an alignment layer is provided on the surface, and the optically anisotropic layer is directly coated on the polishing surface by a composition containing a liquid crystal compound. Or directly coating the layer formed by the alignment layer; (2) laminating the optically anisotropic layer on the film containing the polarizer directly or via another layer; (3) in the above-mentioned polarizer a hard coat layer is laminated on the surface of the film opposite to the surface of the transfer material; and (4) the dummy support is peeled off to be separated from the optically anisotropic layer.

In the above-mentioned transfer material, the surface of the above-mentioned optical anisotropic layer is the film side including the polarizer described above. The method is directly followed by the film including the polarizer, and (2) and (4) are performed in this order.

<12> A method of producing a polarizing plate according to <9>, wherein the manufacturing method comprises: (1) preparing a transfer material comprising a dummy support and an optical anisotropic layer; The dummy support has a brushed surface or an alignment layer provided on the surface, and the optically anisotropic layer is directly coated on the polishing surface by a composition containing a liquid crystal compound or directly coated on the alignment. a layer formed on the layer; (12) the transfer material is directly adhered to the polarizer-containing sheet so that the surface on the side of the optically anisotropic layer is on the side of the film including the polarizer, with respect to the dummy support a film; and (3) a hard coat layer is laminated on a surface of the film including the polarizer opposite to the surface of the transfer material.

The manufacturing method according to any one of <10>, wherein the (2) or (12) is an active energy ray-curable adhesive, and the transfer material is laminated on the above. The polarizer of the laminate obtained by the film including the polarizer is irradiated with an active energy ray from the surface on the side of the optically anisotropic layer.

The production method according to any one of <10> to <13> wherein the polarizer in the film including the polarizer and the optically anisotropic layer are directly followed.

According to the present invention, a polarizing plate of a film is provided. According to the polarizing plate of the present invention, an optical anisotropic layer having various optical compensation capabilities formed of a composition containing a liquid crystal compound and a plurality of polarizers are provided with a minimum configuration, and in particular, it is suitable to provide A polarizing plate used for a front side polarizing plate of a liquid crystal display device or a polarizing plate of an organic EL display device.

1‧‧‧ polarizer

2‧‧‧Optical anisotropic layer

4‧‧‧Protective layer

5‧‧‧hard coating

6‧‧‧Transparent support

12‧‧‧Alignment layer

16‧‧‧false support

21‧‧‧Next layer 1

22‧‧‧Next layer 2

Fig. 1 is a view showing an example of a layer configuration of a polarizing plate of the present invention.

[Formation of the Invention]

Hereinafter, the present invention will be described in detail.

In the present specification, "~" is used in the sense that the numerical values described before and after are included as the lower limit and the upper limit. The "polarizing plate" in the present specification is a size including a long polarizing plate and a size that can be incorporated into a liquid crystal display device unless otherwise specified (in the present specification, "cutting" is defined as It is used in the sense of both polarizing plates such as "punching" and "cutting out". Further, in the present specification, the "polarizing sheet" (also referred to as "polarizing film") and the "polarizing plate" are used, but the "polarizing plate" is intended to mean that at least one side of the "polarizing sheet" has The laminar body of the membrane.

In addition, in the present specification, the description of "(meth) acrylate" means "either or both of acrylate and methacrylate". The same applies to "(meth)acrylic acid".

In the present specification, Re(λ) represents an in-plane retardation at a wavelength λ. Re(λ) can be measured using AxoScan, a polarization phase difference analyzer manufactured by AXOMETRICS. Further, Re(λ) can be measured by causing light having a wavelength of λ nm to enter the film normal direction in KOBRA 21ADH or WR (manufactured by Oji Scientific Instruments Co., Ltd.).

In the present specification, the measurement wavelength is 550 nm unless otherwise specified. For example, when it is simply described as Re, it means Re (550) . Further, in the present specification, the optical isotropic property means that the absolute value of the in-plane retardation (Re (550)) is 10 nm or less. Having an in-plane retardation means that Re (550) is larger than 10 nm.

Further, in the present specification, an angle (for example, an angle such as "90°") and a relationship thereof (for example, "orthogonal", "parallel", and "crossing at 45", etc.) are defined as being included in the present invention. The range of errors allowed in the art to which the invention pertains. For example, it means that the error with respect to the strict angle is preferably 5 or less, more preferably 3 or less, in a range of less than a strict angle of ±10°.

[Polarizer]

The polarizing plate of the present invention comprises an optically anisotropic layer, a polarizing plate, and a hard coat layer. The optically anisotropic layer may be disposed on either or both sides of the polarizer, and is preferably located on either side. The hard coat layer is provided on the surface of the polarizer opposite to the surface on which the optically anisotropic layer is provided. In the case where the optically anisotropic layer is located on both sides of the polarizer, the hard coat layer may be disposed on either side. Further, the polarizing plate may include other layers such as an alignment layer for alignment of the liquid crystal compound when the optically anisotropic layer is formed, a protective layer for protecting the surface of the polarizer or the optically anisotropic layer.

An example of the layer configuration of the polarizing plate of the present invention is shown in Fig. 1.

The film thickness of the polarizing plate is not particularly limited, and may be about 50 μm to 500 μm. In particular, the polarizing plate of the present invention can be formed of a 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, and 70 μm or less.

[Transfer material]

In order to manufacture the polarizing plate of the present invention, it is possible to use a dummy support and A transfer material of an optically anisotropic layer. By undergoing the step of transferring the optically anisotropic layer from the transfer material to the film containing the polarizer, the coated optical anisotropic layer can be formed independently of the kind or property of the film including the polarizer. An optically anisotropic layer of an alignment type of various liquid crystal compounds using various liquid crystal compounds can be formed. For example, the heating step necessary in the step of forming the optical anisotropic layer may affect the properties of the polarizer, but by using the method of manufacturing the transfer material, optical anisotropy can be produced without affecting the polarizer. Floor.

The transfer material is a material that provides an optically anisotropic layer. The dummy support may or may not be peeled off. In the present specification, there is a case where the object to be transferred onto the film including the polarizer, that is, the object to be attached to the film including the polarizer is referred to as a "transfer body". In the present specification, a film containing an optically anisotropic layer obtained by peeling off a dummy support from a transfer material is used.

The transfer material may include an alignment layer for alignment of the liquid crystal compound when the optically anisotropic layer is formed. In this case, it is preferred that the alignment layer and the optically anisotropic layer are in contact with each other. In the transfer material containing the alignment layer, the dummy support and the alignment layer may be in contact with each other. The transfer material may include other layers such as a release layer, a release layer, and the like.

The transfer material can be produced by directly coating a composition containing a liquid crystal compound on the surface of the dummy support or the surface of the alignment layer provided on the dummy support to form an optically anisotropic layer. Preferably, the transfer material is capable of directly applying a polymerizable composition containing a liquid crystal compound on the surface of the dummy support or the surface of the alignment layer provided on the dummy support, and heating the obtained coating layer or Illuminating light The polymerizable composition containing a liquid crystal compound is cured to form an optically anisotropic layer, which is produced.

Hereinafter, each layer included in the polarizing plate or the transfer material will be described in detail.

[optical anisotropic layer]

The optically anisotropic layer is a layer having an incident direction which is substantially not 0 when the retardation is measured, and a layer having optical characteristics which are not isotropic. The optically anisotropic layer used in the present invention is a layer formed of a composition containing a liquid crystal compound. It is preferable that the optically anisotropic layer is formed by polymerizing a liquid crystal compound by irradiating light to a polymerizable composition containing a liquid crystal compound. The polymerizable composition contains a liquid crystal compound having at least one polymerizable group, and the liquid crystal compound may be polymerized by a polymerizable group by irradiation with light or heating. The polymerizable composition is preferably directly applied to an alignment layer provided on the dummy support. The coating layer may be further dried at room temperature or the like, or heated (for example, heated at 50 ° C to 150 ° C, preferably 80 ° C to 120 ° C) to align the liquid crystal compound molecules in the layer. If it is possible to form an optical anisotropic layer by polymerizing it, it is sufficient.

The film thickness of the optically anisotropic layer may be 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, and 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, and may be 0.2 μm or more, 0.3 μm or more, 0.4 μm or more, 0.5 μm or more, 0.6 μm or more, and 0.7. Μm or more, 0.8 μm or more, and 0.9 μm or more.

It is also preferred that the optically anisotropic layer be transparent.

[2-layer optical anisotropic layer]

The polarizing plate may contain two or more optically anisotropic layers. Two or more optically anisotropic layers may be directly in contact with each other in the normal direction, or other layers such as an alignment layer may be sandwiched therebetween. The composition forming the two or more layers may be the same as each other or different. For example, in the combination of the two optically anisotropic layers, a combination of layers formed of a composition containing a rod-like liquid crystal compound or a layer formed of a composition containing a discotic liquid crystal compound may be used. The combination may also be a combination of a layer formed of a composition containing a rod-like liquid crystal compound and a layer formed of a composition containing a discotic liquid crystal compound. When the polarizing plate contains two or more optically anisotropic layers, the optically anisotropic layer which is first produced can function as an alignment layer of an optically anisotropic layer which is formed later. At this time, the optically anisotropic layer which is first produced can be rubbed. When two or more optically anisotropic layers are contained, the total thickness of the optically anisotropic layer is preferably the film thickness described above.

The two-layer optical anisotropic layer, for example, may have a function as a λ/4 phase difference plate in combination. The λ/4 phase difference plate is combined with a polarizer (linear polarizer) to produce a function as a circularly polarizing plate.

The phase difference plate has many uses and has been used in reflective LCDs, semi-transmissive LCDs, luminance enhancement films, organic EL display devices, touch panels, and the like. For example, in an organic EL (organic electroluminescence) device, since a structure having a layer having a different laminated refractive index or a structure using a metal electrode is used, external light is reflected at an interface of each layer, and there is a problem that contrast is lowered or reflected. situation. Therefore, in the past, in order to suppress external light A circularly polarizing plate composed of a phase difference plate and a polarizing plate is used for an organic EL display device or an LCD display device, etc., due to adverse effects caused by reflection.

[Liquid Crystal Compound]

The liquid crystal compound may, for example, be a rod-like liquid crystal compound or a discotic liquid crystal compound.

As the rod-like liquid crystal compound, azomethine, azoxy, cyanobiphenyl, cyanophenyl ester, benzoic acid ester, and cyclohexane carboxy are preferably used. Acid phenyl esters, cyanophenyl cyclohexanes, cyano substituted phenyl pyrimidines, alkoxy substituted phenyl pyrimidines, phenyl dioxanes, diphenyl acetylenes (tolan) and alkenylcyclohexylbenzonitriles. Not only the above low molecular liquid crystalline molecules but also polymer liquid crystal molecules can be used.

The rod-like liquid crystal compound is more preferably fixed by polymerization, and as a polymerizable rod-like liquid crystal compound, it can be used in Makromol. Chem., Vol. 190, p. 2255 (1989); Advanced Materials, Vol. 5, p. 107 (1993) ; U.S. Patent Nos. 4,683,327, 5,622,648, 5,770,107; WO 95/22586, 95/24455, 97/00600, 98/23580, 98/52905; Japanese Patent Laid-Open No.1-272551, No. 6-16616, The compounds described in Japanese Unexamined Patent Publication No. Hei No. No. Hei. No. Hei. In addition, as the polymerizable rod-like liquid crystal compound, a polymerizable rod-like liquid crystal compound represented by the following formula (1) is preferably used.

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

In the following, the polymerizable rod-like liquid crystal compound represented by the formula (1) will be further described.

In the formula (1), Q ¹ and Q ² are each independently a polymerizable group. The polymerization reaction of the polymerizable group is preferably an addition polymerization (including ring-opening polymerization) or a condensation polymerization. In other words, the polymerizable group is preferably a functional group capable of undergoing an addition polymerization reaction or a condensation polymerization reaction. An example of a polymerizable group is shown below.

-SH -OH -NH ₂

Among the above, preferred examples of the polymerizable group include an acryl group and a methacryl group. In particular, both of Q ¹ and Q ² in the formula (1) are preferably an acrylic group or a methacryl group.

In the formula (1), L ¹ and L ⁴ are each a separate divalent linking group. L ¹ and L ^{4 are} preferably each independently derived from -O-, -S-, -CO-, -NR-, -C=N-, a divalent chain group, a divalent cyclic group, and A combination of selected bivalent linkers. The above 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.

Examples of the combined divalent linking group are shown below. Here, the left side is bonded to Q (Q ¹ or Q ² ), and the right side is bonded to Cy (Cy ¹ or Cy ³ ).

L-1:-CO-O-divalent chain-based-O-

L-2: -CO-O-bivalent chain-based-O-CO-

L-3:-CO-O-bivalent chain-based O-CO-O-

L-4: -CO-O-divalent chain-based-O-divalent cyclic group-

L-5: -CO-O-divalent chain-based-O-divalent cyclic group-CO-O-

L-6:-CO-O-divalent chain-based-O-divalent cyclic group-O-CO-

L-7: -CO-O-divalent chain-based-O-divalent cyclic group-divalent chain group-

L-8: -CO-O-divalent chain-based-O-divalent cyclic group-divalent chain group-CO-O-

L-9:-CO-O-divalent chain-based-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-based O-CO-O-divalent cyclic group-

L-17:-CO-O-divalent chain-based O-CO-O-divalent cyclic group-CO-O-

L-18:-CO-O-divalent chain-based O-CO-O-divalent cyclic group-O-CO-

L-19:-CO-O-divalent chain-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-like group means an alkyl group, a substituted alkyl group, an alkenyl group, a substituted alkenyl group, an alkynyl group, or a substituted alkynyl group. Preferred are an alkyl group, a substituted alkyl group, an alkenyl group, a substituted alkenyl group, more preferably an alkyl group and an alkenyl group.

The alkylene group may have a branch. The carbon number of the alkylene group is preferably from 1 to 12, more preferably from 2 to 10, most preferably from 2 to 8.

The alkylene moiety of the substituted alkylene group is the same as the above alkylene group. Examples of the substituent include a halogen atom.

The alkenyl group may have a branch. The carbon number of the alkenyl group is preferably from 2 to 12, more preferably from 2 to 10, most preferably from 2 to 8.

The alkenyl group of the substituted alkenyl group is the same as the above-described alkenyl group. Examples of the substituent include a halogen atom.

The alkynyl group may have a branch. The carbon number of the alkynyl group is preferably from 2 to 12, more preferably from 2 to 10, most preferably from 2 to 8.

The alkynyl moiety of the substituted alkynyl group is the same as the above alkynyl group. Examples of the substituent include a halogen atom.

Specific examples of the divalent chain-like group include an exoethyl group, a trimethylene group, a propylene group, a tetramethylene group, a 2-methyl-tetramethylene group, and a methylene group. A group, a hexamethylene group, an octamethylene group, a 2-butenbutenyl group, a 2-butenyl group, and the like.

The definitions and examples of the divalent cyclic group are the same as the definitions and examples of Cy ¹ , Cy ² and Cy ³ which will be described later.

In the formula (1), L ² or L ³ are each a separate single bond or a divalent linking group. L ² and L ^{3 are} preferably each independently derived from -O-, -S-, -CO-, -NR-, -C=N-, a divalent chain group, a divalent cyclic group, and A combination of selected bivalent linkers or single bonds. The above 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, and most preferably a hydrogen atom. . The divalent chain group and the divalent cyclic group are synonymous with the definitions of L ¹ and L ⁴ .

Preferred examples of the divalent linking group of L ² or L ³ include -COO-, -OCO-, -OCOO-, -OCONR-, -COS-, -SCO-, -CONR-, -NRCO-, -CH ₂ CH ₂ -, -C=C-COO-, -C=N-, -C=NN=C-, and the like.

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

In the formula (1), Cy ¹ , Cy ² and Cy ³ are each independently a divalent cyclic group.

The ring included 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, a single ring is preferred over a condensed ring.

The ring included in the cyclic group may be any of an aromatic ring, an aliphatic ring, and a hetero 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, a 1,4-phenyl group is preferred. As the cyclic group having a naphthalene ring, a naphthalene-1,5-diyl group and a naphthalene-2,6-diyl group are preferred. As the cyclic group having a cyclohexane ring, a 1,4-cyclohexylene group is preferred. As the cyclic group having a pyridine ring, a pyridine-2,5-diyl group is preferred. As the cyclic group having a pyrimidine ring, a pyrimidine-2,5-diyl group is preferred.

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, a decyloxy group having 2 to 6 carbon atoms, an alkoxycarbonyl group having 2 to 6 carbon atoms, an amine carbaryl group, and a carbon number of 2 to 6. An alkyl substituted amine indenyl group and an anthranyl group having 2 to 6 carbon atoms.

In the following, an example of the polymerizable rod-like liquid crystal compound represented by the formula (1) is shown, but examples of the polymerizable rod-like liquid crystal compound are not limited thereto.

In addition, as the rod-like liquid crystal compound, in addition to the polymerizable rod-like liquid crystal compound represented by the formula (1), at least one compound represented by the following formula (2) is preferably used in combination.

General formula (2) M ¹ -(L ¹ )p-Cy ¹ -L ² -(Cy ² -L ³ )n-Cy ³ -(L ⁴ )qM ² (in the formula (2), M ¹ and M ² is independently represented by 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 a Q ^{1 group.} However, at least one of M ¹ and M ² represents a group other than Q ¹ .

Among them, Q ¹ , L ¹ , L ² , L ³ , L ⁴ , Cy ¹ , Cy ² , Cy ³ and n are synonymous with the group represented by the formula (1). Also, p and q are 0 or 1).

In the case where 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 The alkyl group having 1 to 4 carbon atoms or the phenyl group, p and q are preferably 0.

Further, a preferred mixing ratio (quality) of the compound represented by the formula (2) in the mixture of the polymerizable liquid crystal compound represented by the formula (1) and the compound represented by the formula (2) The ratio is 0.1% to 40%, preferably 1% to 30%, more preferably 5% to 20%.

Preferred examples of the compound represented by the formula (2) are shown below, but the invention is not limited thereto.

Discotic liquid crystal compounds are described in various literatures (C. Destrade et al., Mol. Cryst. Liq. Cryst., vol. 71, p. 111 (1981); edited by the Chemical Society of Japan, quarterly chemical general, No. 22, liquid crystal Chemistry, Chapter 5, Chapter 10, Section 2 (1994); B. Kohne et al., Angew. Chem. Soc. Chem. Comm., p. 1794 (1985); J. Zhang et al., J. Am. Chem. Soc., vol. 116, p. 2655 (1994)). The polymerization of a discotic liquid crystal compound is described in JP-A-8-27284. In order to fix the discotic liquid crystal compound by polymerization, it is necessary to bond the polymerizable group which is a substituent to the disc-shaped core of the discotic liquid crystal compound. However, when the polymerizable group is directly bonded to the disk-shaped core, it becomes difficult to maintain the alignment state in the polymerization reaction. Therefore, a linking group is introduced between the disc-shaped 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 (-L-P)n (in the 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 examples of the disc-shaped core (D), the divalent linking group (L), and the polymerizable group (P) in the formula (3) are each described in JP-A-2001-4837 (D1). )~(D15), (L1)~(L25), (P1)~(P18), it is preferable to use the content described in this publication.

In addition, as the discotic liquid crystal compound, a compound represented by the formula (DI) described in JP-A-2007-2220 is preferably used.

When the mass of the solid component (the mass of the solvent to be removed) of the composition for forming the optical anisotropic layer is 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. The liquid crystal compound may be used in an amount of not less than 5% by mass and not more than 99.7% by mass. In particular, it is preferably contained in an amount of 70% by mass or more, 80% by mass or more, and 90%. A compound containing an acrylic group or a methacryl group based on the mass% or more, or 95% by mass or more, and 99.99% by mass or less, 99.98 mass% or less, and 99.97% by mass or less.

The liquid crystal compound may be fixed in any of an alignment state, a vertical alignment, a tilt alignment, and a twist alignment. In the present specification, "horizontal alignment" means that the long axis of the molecule is parallel to the horizontal plane of the transparent support in the case of a rod-like liquid crystal, and the discotic liquid crystal compound in the case of a discotic liquid crystal. The disc face of the core is parallel to the horizontal plane of the transparent support, but is not required to be strictly parallel. In this specification, it is intended to mean an directional angle formed by the horizontal plane of less than 10 degrees. The optically anisotropic layer used in the present invention is preferably contained in a state in which the rod-like liquid crystal compound is aligned in a horizontal alignment.

[Solvent]

As a solvent to prepare a coating liquid when a composition containing a liquid crystal compound is prepared as a coating liquid, it is preferred to use an organic solvent or water or a mixed solvent thereof. Examples of the organic solvent include decylamine (for example, N,N-dimethylformamide), anthraquinone (for example, dimethyl hydrazine), a heterocyclic compound (for example, pyridine), and a hydrocarbon (for example). , benzene, hexane), alkyl halides (eg, chloroform, dichloromethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, methyl ethyl ketone, methyl isobutyl) Ketone, cyclohexanone), ether (for example, tetrahydrofuran, 1,2-dimethoxyethane), alkyl alcohol (for example, methanol, ethanol, propanol). Further, two or more kinds of solvents may be used in combination. Among the above, an alkyl halide, an ester, a ketone, and a mixed solvent thereof are preferred.

[Alignment fixation]

The immobilization of the alignment of the liquid crystal compound is preferably carried out by a crosslinking reaction of a polymerizable group into which a liquid crystal compound has been introduced, and more preferably carried out by a polymerization reaction of a 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 is preferably a radical polymerization.

Examples of the radical photopolymerization initiator include an α-carbonyl compound (described in each specification of U.S. Patent Nos. 2,276,661 and 2,367,670), a sulfonium ether (described in the specification of U.S. Patent No. 2,448,828), and an α-hydrocarbon-substituted aromatic oxime compound. (Described in the specification of U.S. Patent No. 2,722,512), a combination of a polynuclear ruthenium compound (described in each specification of U.S. Patent No. 3,046,127 and No. 2,591,758), a combination of a triaryl imidazole dimer and a p-aminophenyl ketone (described in the specification of U.S. Patent No. 3,549,367) Acridine and brown a compound (described in Japanese Unexamined Patent Publication No. Hei No. Hei. No. Hei. The oxadiazole compound (described in the specification of U.S. Patent No. 4,212,970). Examples of the cationic photopolymerization initiator include an organic phosphonium salt system, an iodonium salt system, and an onium salt system, and are preferably an organic phosphonium salt system, and particularly preferably a triphenylsulfonium salt. As the counter ion of these compounds, hexafluoroantimonate, hexafluorophosphate or the like is preferably used.

The radical thermal polymerization initiator is a compound which generates a radical by heating to a temperature higher than a decomposition temperature. Examples of such a radical thermal polymerization initiator include antimony peroxide (peroxide, benzamidine peroxide, etc.), and ketone peroxide (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.). ), hydroperoxide (hydrogen peroxide, tert-butyl hydroperoxide, Alkenyl hydroperoxide, etc., dialkyl peroxide (di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc.), peroxyesters (peroxidation) Tert-butyl acetate, tert-butyl peroxy-pivalate, etc., azo compounds (azobisisobutyronitrile, azobisisovaleronitrile, etc.), persulfuric acid Salts (ammonium persulfate, sodium persulfate, potassium persulfate, etc.).

The amount of the polymerization initiator used is preferably from 0.01 to 20% by mass, more preferably from 0.5 to 5% by mass, based on the solid content of the coating liquid. It is preferred to use ultraviolet rays for light irradiation for photopolymerization of a liquid crystal compound. The irradiation energy is preferably from 10 mJ/cm ² to 10 J/cm ² , more preferably from 25 to 1000 mJ/cm ² . The illuminance is preferably from 10 to 2,000 mW/cm ² , more preferably from 20 to 1,500 mW/cm ² , still more preferably from 40 to 1,000 mW/cm ² . As the irradiation wavelength, it is preferable to have a peak at 250 to 450 nm, and more preferably a peak at 300 to 410 nm. In order to promote the photopolymerization reaction, light irradiation may be carried out in an inert gas atmosphere such as nitrogen or under heating.

The heating for the thermal polymerization of the liquid crystal compound is preferably carried out in 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 compound represented by the general formulae (1) to (3) described in the paragraphs "0098" to "0105" of JP-A-2009-69793, and the use thereof can be used. At least one of the fluorine-containing homopolymer or copolymer of the monomer of the formula (4) is used to align the molecular level of the liquid crystal compound. In the case where the liquid crystal compound is horizontally aligned, the inclination angle thereof is preferably 0 to 5 degrees, more preferably 0 to 3 degrees, still more preferably 0 to 2 degrees, and most preferably 0 to 1 degree.

The amount of the horizontal alignment agent to be added is preferably from 0.01 to 20% by mass, more preferably from 0.01 to 10% by mass, particularly preferably from 0.02 to 1% by mass, based on the mass of the liquid crystal compound. In addition, the compounds represented by the general formulae (1) to (4) described in the paragraphs "0098" to "0105" of JP-A-2009-69793 may be used singly or in combination of two or more.

[Other additives]

The composition containing the liquid crystal compound may include the onium salt described in paragraphs 0121 to 0148 of JP-A-2013-050583, and in particular, pyridinium represented by the formula (I) described in JP-A-2006-113500. ) compound. The onium salt can function as a vertical alignment agent on the interface side of the alignment layer, for example, a molecule of a discotic liquid crystal compound can be vertically aligned in the vicinity of the alignment layer. In addition, the composition containing a liquid crystal compound may contain the boric acid compound represented by the formula (1) described in JP-A-2013-054201.

The composition containing the liquid crystal compound may contain other necessary additives, but preferably does not contain a so-called Chiral reagent.

[Coating method]

The coating of the composition when forming the optically anisotropic layer can be applied by immersion coating, air knife coating, spin coating, slit coating, curtain coating, roll coating, wire bar coating. This is carried out by a method, a gravure coating method or an extrusion coating method (U.S. Patent No. 2,681,294). More than two layers can be applied simultaneously. The method of the simultaneous coating is described in U.S. Patent Nos. 2,761,791, 2,941, 198, 3, 508, 947, and 3, 525, 528, and the coating engineering of Nakasaki, 253 pages, as described in Asakura Shoten (1973).

[false support]

The dummy support is not particularly limited, and may be rigid or flexible, but is preferably flexible at a point where it is easy to handle. The rigid support is not particularly limited, and examples thereof include a soda glass plate having a yttrium oxide film on the surface, a glass plate, an aluminum plate, and an iron such as a low-expansion glass, an alkali-free glass, or a quartz glass plate. Metal plates such as plates and SUS plates, resin plates, ceramic plates, slate, etc. The flexible support is not particularly limited, and examples thereof include cellulose esters (for example, cellulose acetate, cellulose propionate, cellulose butyrate), and polyolefins (for example, norbornene polymerization). , poly(meth)acrylate (for example, polymethyl methacrylate), polycarbonate, polyester (for example, polyethylene terephthalate or polyethylene naphthalate), poly A plastic film or paper, an aluminum foil, a cloth, or the like, such as a fluorene-based olefin polymer (for example, a norbornene-based resin (ZEONON, ZEONOR, ZEONOR, JSR, manufactured by ZEON Co., Ltd.)). Among them, polyethylene terephthalate (PET) is more preferred. The film thickness of the rigid support is preferably from 100 to 3,000 μm, more preferably from 300 to 1,500 μm, from the viewpoint of easiness of handling. The film thickness of the flexible support may be about 5 μm to 1000 μm, preferably 10 μm to 250 μm, and more preferably 15 μm to 90 μm.

In the research process of the present inventors, it has been found that a polarizing plate of a film containing a hard coat layer is liable to curl. In particular, there is a case where the polarizing plate is curled to the side where the polarizer is recessed to the side of the hard coat layer. Such curling is not preferable when a polarizing plate is laminated on another film by a flow such as a roll to roll. The present inventors have found that such crimping is performed after the transfer material is placed on the surface of the optically anisotropic layer on the film containing the polarizer. It does not occur when the dummy support is peeled off. For this reason, the polarizing plate of the present invention is preferably conveyed by a structure including a dummy support, and is cut into an appropriate size immediately before being assembled toward the display device, and is newly peeled off immediately after peeling off the dummy support. Set an adhesive layer or separator film.

[Alignment layer]

An alignment layer can be used for the formation of the optically anisotropic layer. The alignment layer may be provided on the surface of the dummy support or the undercoat layer (which may be an optically anisotropic layer) which has been coated on the dummy support. The alignment layer functions to regulate the alignment of the liquid crystal compound in the composition provided thereon. The alignment layer may be any layer if it is capable of imparting an alignment to the optical anisotropic layer. Not only a well-known material as a vertical alignment film but also a well-known material as a horizontal alignment film can be selected. Examples of the alignment layer include a layer containing an organic compound (preferably a polymer), and an optical alignment layer which exhibits alignment of liquid crystals by polarized light typified by azobenzene polymer or polyvinyl cinnamate. An oblique vapor-deposited layer of an inorganic compound, and a layer having micro-groove, and additionally using ω-trisuccinic acid, dioctadecylmethylammonium chloride, and methyl stearate An accumulation film formed by the Langmuir-Blodgett method (LB film) or a layer in which a dielectric body is aligned by application of an electric field or a magnetic field. As the alignment layer, a polymer layer is preferred, and a polymer layer containing a modified or unmodified polyvinyl alcohol is particularly preferred. The modified or unmodified polyvinyl alcohol can be used as a horizontal alignment film, but by the addition of a ruthenium compound to the composition for forming an optical anisotropic layer, the action of the ruthenium compound and the alignment film, and the ruthenium compound and The role of liquid crystal compounds, etc. The liquid crystal molecules are aligned at an alignment film interface to a tilted alignment state or a vertical alignment state of a high average tilt angle. The modified polyvinyl alcohol-based functional group is used to modify at least one hydroxyl group of the polyvinyl alcohol, and for example, a polyvinyl alcohol is modified with an ethyl acetonitrile group, a sulfonic acid group, a carboxyl group, an oxyalkylene group or the like. As the alignment film, an alignment film containing a modified polyvinyl alcohol containing a unit having a polymerizable group is preferably used. This is because the adhesion to the optically anisotropic layer can be further improved. Further, a polyvinyl alcohol having at least one hydroxyl group substituted with a vinyl moiety, an oxiranyl moiety or an aziridinyl moiety is preferred, and is preferably, for example, Japanese Patent No. 3907735. The modified polyvinyl alcohol described in paragraphs [0071] to [0095].

The thickness of the alignment layer is preferably from 0.01 to 5 μm, more preferably from 0.05 to 2 μm.

[grinding treatment]

It is preferable to apply a rubbing treatment to the surface of the alignment layer, the dummy support, or the optically anisotropic layer. 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 in a predetermined direction with paper or cloth. The general method of the brushing process is described in, for example, "Liquid Crystal Handbook" (published by Maruzen Co., Ltd., October 30, 2009).

As a method of changing the brush density, the method described in "Liquid Crystal Handbook" (published by Maruzen Co., Ltd.) can be used. The brush density (L) is quantified by the following formula (A).

Formula (A) L = N1 (1 + 2πrn / 60v)

In the formula (A), the number of N-type brushes, the contact length of the 1-type brush roller, r The radius of the roller, the number of revolutions of the n-roller (rpm), and the speed of the v-stage (second speed).

If the brushing density is increased, the number of times of brushing is increased, the contact length of the brush roller is increased, the radius of the roller is increased, the number of rotations of the roller is increased, and the moving speed of the stage is lowered. On the other hand, if Brush the density, and vice versa.

Further, as a condition at the time of the rubbing treatment, the description of Japanese Patent No. 4052558 can be referred to.

[hard coating]

The polarizing plate of the present invention contains a hard coat layer. In the case of the polarizer, the hard coat layer may be provided on the side opposite to the side on which the optically anisotropic layer is provided. A hard coat layer may be included as the outermost layer of the polarizing plate, or another layer may be additionally provided on the outer side of the hard coat layer.

In the present specification, the hard coat layer refers to a layer in which the pencil hardness of the polarizing plate is increased due to its formation. Specifically, the pencil hardness (JIS K5400) after lamination of the hard coat layer is a layer of H or more. When the pencil hardness after lamination of the hard coat layer is preferably 2H or more, more preferably 3H or more. The thickness of the hard coat layer is preferably from 0.4 to 35 μm, more preferably from 1 to 30 μm, most preferably from 1.5 to 20 μm.

The polarizing plate, in particular, the front polarizing plate of the liquid crystal display device or the polarizing plate of the organic EL display device requires physical strength (scratch resistance, etc.), transparency, chemical resistance, weather resistance (moisture resistance, light resistance, etc.). Further, in order to prevent a decrease in contrast due to reflection of external light or reflection of an image, anti-glare performance or anti-reflection performance is required. The hard coat layer can be provided for imparting such properties to the surface of the polarizing plate.

Specific examples of the hard coat layer include the description of the hard coat layer in JP-A-2012-103689, and the description of the antiglare layer in JP-A-2012-185290, which includes particles and ultraviolet curing. A layer formed by the composition of the resin. As described in Japanese Laid-Open Patent Publication No. 2012-103689, the hard coat layer may have a plurality of layers having different refractive indices as an antireflection layer.

(transparent support)

The hard coat layer is preferably formed of a composition coated on the surface of the transparent support. In the present specification, the transparent means that the transmittance of visible light is 60% or more, preferably 80% or more, and particularly preferably 90% or more. Examples of the material of the transparent support are a cellulose-based polymer represented by triacetyl cellulose, a polycarbonate polymer, polyethylene terephthalate or polyethylene naphthalate. A polyester polymer such as an ester, a (meth)acrylic polymer such as polymethyl methacrylate, or a styrene polymer such as polystyrene or acrylonitrile-styrene copolymer (AS resin). Further, a polyolefin such as polyethylene or polypropylene, a polyolefin polymer such as an ethylene-propylene copolymer, a vinyl chloride polymer, a guanamine polymer such as nylon or an aromatic polyamide, or a ruthenium-based polymer may be mentioned. Amine polymer, fluorene polymer, polyether fluorene polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinylidene chloride polymer, vinyl alcohol polymer, vinyl butyl Examples of the aldehyde polymer, the arylate polymer, the polyoxymethylene polymer, the epoxy polymer, or the polymer of the mixed polymer are exemplified.

Moreover, as a material which forms a transparent support, it is preferable to use a thermoplastic norbornene-type resin. Thermoplastic norbornene-based resin ZEONEX, ZEONOR, and JSR (manufactured by JSR) of Japanese ZEON Co., Ltd. can be cited.

When the transparent support contains one or two or more of the above polymers as a main component, for example, it may be 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, or 99% by mass or more. Or 100% by mass.

When the thickness of the transparent support is from 1 μm to 200 μm, it is preferably from 5 μm to 100 μm.

[Polarizer]

Examples of the polarizer include an iodine-based polarizer, a dye-based polarizer using a dichroic dye, and a polyene-based polarizer. The iodine-based polarizer and the dye-based polarizer are generally produced using a polyvinyl alcohol film. In the present invention, any polarizer can be used. For example, the polarizer is preferably composed of a modified or unmodified polyvinyl alcohol and a dichroic molecule. For the polarizer composed of a modified or unmodified polyvinyl alcohol and a dichroic molecule, for example, the description of JP-A-2009-237376 can be referred to. When the thickness of the polarizer is 50 μm or less, it is preferably 30 μm or less, and more preferably 20 μm or less. Further, the film thickness of the polarizer is usually 1 μm or more, 5 μm or more, or 10 μm or more.

[film containing polarizer]

The film containing the polarizer of the transfer body may include only the polarizer, or may include other layers such as a protective layer in addition to the polarizer.

[protective layer (protective film)]

The polarizing plate may include a protective layer. For example, a protective layer may be provided on either or both sides of the polarizer to form the above-described film including the polarizer. also In the transfer material, a protective layer may be previously provided on the opposite side (preferably the outermost side) from the side of the dummy support as viewed from the optically anisotropic layer. Further, after the transfer material or the transfer body and the film including the polarizer are attached, the protective layer may be provided on either one side or both sides.

The protective layer can be provided, for example, by directly coating and drying the protective layer forming composition on the surface on which the protective layer is provided to directly contact other layers, but it is usually possible to use an adhesive to continue The above surface. The adhesive or the adhesive may be the same as the adhesive used for the subsequent transfer material and the film containing the polarizer.

As the protective layer, a deuterated cellulose polymer film, an acrylic polymer film ((meth)acrylic polymer film), or a cycloolefin polymer film can be used. For the deuterated cellulose-based polymer, the description relating to the deuterated cellulose-based resin of JP-A-2011-237474 can be referred to. For the cycloolefin polymer film, the descriptions of JP-A-2009-175222 and JP-A-2009-237376 can be referred to. By including a cycloolefin polymer film, it is possible to impart moisture permeability to the polarizing plate. Moisture permeability means the property that water does not pass but water vapor passes.

When the protective layer contains one or two or more of the above polymers as a main component, for example, it may be 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, or 99% by mass or more. Or 100% by mass.

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, or 10 μm or less, and may be 1 μm or more, 5 μm or more, or 10 μm or more.

[Next layer]

In the polarizing plate of the present invention, an optically anisotropic layer is provided on one side of the film including the polarizer, and the interlayer is interposed. A hard coat layer is provided on the other side, but a hard coat layer may be provided in the back layer. In the case of a hard coat layer on the transparent support, it is preferred to follow the surface on the transparent support side, more preferably directly to the transparent support and the polarizer. In the present specification, there is a film in which a polarizer is included and an optically anisotropic layer (transfer material or transfer body), followed by an adhesive layer, which is a film comprising a polarizer and a hard coat layer. The layer then follows the case of layer 2.

If the adhesive layer is formed by an adhesive, it may be. In this specification, "Next" is used under the concept of "adhesive". The adhesive is not particularly limited, and examples thereof include a polyvinyl alcohol-based adhesive; an aqueous solution of a boron compound; and the curability of an epoxy compound having no aromatic ring in the molecule as shown in JP-A-2004-245925. An active energy ray-curable adhesive containing a photopolymerization initiator having a molar absorption coefficient of 400 or more and a UV curable compound at a wavelength of 360 to 450 nm described in JP-A-2008-174667 as an essential component; 100 parts by mass of the total amount of the (meth)acrylic compound described in JP-A-2008-174667 contains (a) a (meth)acrylic compound having two or more (meth)acrylonyl groups in the molecule, (b) a (meth)acrylic compound having a hydroxyl group in the molecule, having only one polymerizable double bond, and (c) a phenol ethylene oxide modified acrylate or a nonylphenol ethylene oxide modified acrylate An active energy ray-curable adhesive or the like.

Further, the polyvinyl alcohol-based adhesive is an adhesive containing modified or unmodified polyvinyl alcohol. The polyvinyl alcohol-based adhesive may further contain a crosslinking agent in addition to the modified or unmodified polyvinyl alcohol. As an adhesive Specific examples thereof include an aqueous solution of polyvinyl alcohol or polyvinyl acetal (for example, polyvinyl butyral) or a vinyl polymer (for example, polyvinyl chloride, polyvinyl acetate, or polybutyl acrylate). emulsion. A particularly preferred adhesive is an aqueous solution of polyvinyl alcohol. At this time, the polyvinyl alcohol is preferably completely saponified.

Among them, a polyvinyl alcohol-based adhesive and an active energy ray-curable adhesive are preferred.

Layer 1 and subsequent layer 2 may then be of the same material or different.

The thickness of the subsequent layer is preferably any of the layer 1 and the layer 2, and is preferably 0.01 to 10 μm, particularly preferably 0.05 to 5 μm, in terms of dry film thickness.

[other functional 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 in addition to the above layers.

(release layer)

The release layer is provided between the dummy support and the transfer body, and the dummy support is peeled off in the manufacturing step of the polarizing plate, together with the layer from which the dummy support is peeled off from the transfer material. By using a release layer, the peeling between the dummy support and the transfer body can be stabilized, and the transfer property at the time of transfer can be improved.

As the release layer, a release resin, a resin containing a release agent, and a curable resin which is crosslinked under light irradiation can be applied. Examples of the mold release resin include a fluorine resin, an anthrone, a melamine resin, an epoxy resin, a polyester resin, an acrylic resin, and a cellulose resin. Preferred examples thereof include a melamine resin. Examples of the resin containing the release agent include mold release of a fluorine resin, an anthrone, and various waxes. An acrylic resin, a vinyl resin, a polyester resin, a cellulose resin, or the like added or copolymerized.

The formation of the release layer may be carried out by dispersing or dissolving the resin in a solvent, and coating and drying it by a known coating method such as roll coating or gravure coating. Further, it may be heated and dried or aged at a temperature of 30 ° C to 120 ° C as needed, or irradiated with ionizing radiation to crosslink. 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 peeling layer is provided between the dummy support and the transfer body, and when the dummy support is peeled off in the manufacturing step of the polarizing plate of the present invention, the transfer body obtained by peeling the dummy support from the transfer material is the most The layer of the surface. The peeling of the dummy support from the transfer material is stabilized by using the release layer.

Since the release layer becomes the outermost surface of the transfer body, it is preferably surface-protective. The material of the release layer has a peeling property with the dummy support, and has an adjacent layer (alignment layer, optical anisotropic layer, or the like) formed on the side opposite to the dummy support as viewed from the release layer. The adhesiveness is not particularly limited, and for example, an acrylic resin, a vinyl chloride-vinyl acetate copolymer resin, a polyester resin, a polymethacrylate resin, a polyvinyl chloride resin, a cellulose resin, or a crucible can be used. Ketone resin, chlorinated rubber, casein, metal oxide, and the like. They can be used in combination of two or more kinds. Further, a release agent such as a fluorine resin, an anthrone or a wax, or various surfactants may be added or copolymerized thereto.

In the transfer material, it is preferred that the optically anisotropic layer or the alignment layer also serves as a release layer.

[Manufacturing method of polarizing plate]

In the polarizing plate of the present invention, the optically anisotropic layer in the transfer material can be laminated on the one side surface side of the film including the polarizer, and the hard coat layer can be laminated on the other surface side of the film including the polarizer. No matter which one layer is built first. When the optically anisotropic layer is laminated on one side of the film including the polarizer, the surface on the side of the optically anisotropic layer becomes the side of the polarizer relative to the dummy support, and then the transfer material is transferred or transferred from the transfer. The transfer body of the material peeling dummy support may be attached to the film containing the polarizer. Next, the surface of the transfer body of the film including the polarizer may be any of an optically anisotropic layer, an alignment layer, a release layer, and the like.

The dummy support may be peeled off after the transfer material is passed over the film containing the polarizer.

The peeling method of the dummy support is not particularly limited. Preferably, the peeling of the dummy support is carried out at a rate at which no breakage occurs.

In the case where the prepared transfer material is larger than the produced polarizing plate, the transfer material can be cut before the dummy support is peeled off. For example, it can be made into a width of more than 1.5m roll transfer material cut, cut into a 0.1m ² or less, 0.05m ² or less, 0.03m ² or less, 0.025m ² or less, 0.02m ² or less, 0.01M Any shape such as a square or a rectangle having a size of ² or less, 0.005 cm ² or less, or 0.003 m ² or less. The lower limit of the shape is not particularly limited, and may be a size that can be treated according to the purpose. However, it is usually not more than 0.0001 m ² (1 cm ² ).

The transfer material or the outermost surface of the transfer body may be followed by a polarizer in the film including the polarizer, or may be followed by a polarizer. The layer other than the layer is preferably followed by a polarizer. The hard coat layer may be followed by a polarizer in the film containing the polarizer, or may be followed by a layer other than the polarizer, but is preferably followed by a polarizer. In particular, it is preferred that the hard coat layer is followed by a transparent support adjacent to the hard coat layer and then to the film comprising the polarizer, preferably directly following the transparent support and the polarizer. This can be done by using the above-mentioned adhesive. When the transfer material or the transfer body is attached to the film including the polarizer, when the active energy ray-curable adhesive is used, the polarizer can be irradiated with an active energy ray such as ultraviolet rays from the optical anisotropic side, and hardened. The agent forms an adhesive layer. It is preferred to use an active energy ray-curable adhesive when directly following the optical anisotropy and the polarizer.

[Examples]

Hereinafter, the present invention will be further specifically described by way of examples. The materials, reagents, masses, ratios, operations, and the like shown in the following examples can be appropriately changed without departing from the spirit of the invention. Therefore, the scope of the invention is not limited to the following examples.

[Manufacture of transfer material]

(formation of alignment layer)

PET (thickness: 75 μm) made of Fujifilm was prepared as a dummy support, and an alignment layer coating liquid having the following composition was continuously applied by a wire rod of #14. It was dried under a warm air of 60 ° C for 60 seconds, and further dried under a warm air of 100 ° C for 120 seconds. The modified polyvinyl alcohol used had a degree of saponification of 96.8%. The film thickness of the obtained alignment film was 0.5 μm.

(Production of optical anisotropic layer 1 with alignment layer)

On the alignment layer (fake support), the coating liquid shown below was applied by extrusion coating to the polishing surface of the alignment layer which had been subjected to the rubbing treatment. Thereafter, it was dried at room temperature for 30 seconds, and then heated in a gas atmosphere of 90 ° C for 2 minutes. Thereafter, a bulb (lamp 90 mW/cm) made of FUSION was subjected to 60% output at 60% for 6 to 12 seconds. The UV irradiation produces an optically anisotropic layer. The coating was carried out so that the film thickness of the optically anisotropic layer was 3.0 μm. The average tilt angle of the rod-like liquid crystal compound to the film surface was 0°, and it was confirmed that the rod-like liquid crystal compound was aligned horizontally on the film surface.

[Production of polarizing plate 1 with dummy support]

(production of polarizer)

A roll-shaped polyvinyl alcohol film having a thickness of 80 μm was continuously stretched five times in an iodine aqueous solution, and dried to obtain a polarizing film (polarizer) having a thickness of 20 μm.

(Modulation of coating liquid for anti-glare layer)

Each component and a mixed solvent of MIBK (methyl isobutyl ketone) and MEK (methyl ethyl ketone) (89 to 11 (mass ratio)) were mixed in such a manner as to have the following composition. The coating liquid 1 for an anti-glare layer was prepared by filtering with a polypropylene filter having a pore size of 30 μm. The solid content concentration of each coating liquid was 40% by mass. Moreover, when preparing a coating liquid, resin particle and smectite are added in the state of the dispersion liquid mentioned later.

(Modulation of Resin Particle Dispersion)

In the dispersion of the translucent resin particles, the translucent resin particles (TECHPOLYMER SSX, manufactured by Sekisui Seisakusho Co., Ltd.) were gradually added to the MIBK solution while stirring until the solid content concentration of the dispersion became 30% by mass. Modulated in minutes.

(modulation of bentonite dispersion)

In the dispersion of the bentonite, all of the MEK used in the coating liquid for the final anti-glare layer was added, and the bentonite (LUCENTITE STN, manufactured by CO-OP CHEMICAL Co., Ltd.) was slowly added while stirring in MEK, and the mixture was stirred for 30 minutes. .

[Production of transparent support with anti-glare layer]

(application of anti-glare layer)

A commercially available deuterated cellulose film (FUJITAC ZRD40, manufactured by Fujifilm Co., Ltd., film thickness: 40 μm) was taken up in a roll form, and an anti-glare layer was applied so as to have a film thickness of 4 μm by using the coating liquid 1 for an anti-glare layer. .

Specifically, the coating liquid was applied by a die coating method of the slit die described in Example 1 of JP-A-2006-122889, and the coating liquid was applied at a conveying speed of 30 m/min, and dried at 80 ° C for 150 seconds. Further, under a nitrogen purge, an air-cooled metal halide lamp (manufactured by EYEGRAPHICS Co., Ltd.) of 160 W/cm was used at an oxygen concentration of about 0.1%, and ultraviolet rays having an illuminance of 400 mW/cm ² and an irradiation amount of 180 mJ/cm ² were irradiated. After the coating layer is hardened to form an antiglare layer, it is wound up to prepare a transparent support having an antiglare layer.

The transparent support with the antiglare layer was immersed in a 1.5 mol/L NaOH aqueous solution (saponification liquid) stored at 55 ° C for 2 minutes, and then the film was washed with water, followed by immersion in a 0.05 mol/L sulfuric acid aqueous solution at 25 ° C for 30 seconds. Thereafter, the water was further bathed under a 30-second running water to make the film neutral. Then, the air knife was drained three times, and after the water was removed, it was allowed to stand in a drying zone at 70 ° C for 15 seconds to be dried to prepare a saponified film.

On the side of the deuterated cellulose film side, PVA (KURARAY ( P), PVA-117H) 3% aqueous solution is an adhesive, and the longitudinal direction of the produced reel of the polarizer is parallel to the longitudinal direction of the reel of the transparent support with the anti-glare layer. The saponified transparent support with an anti-glare layer obtained in this manner is bonded to one side of the polarizer.

The surface of the optical anisotropic layer 1 on the surface of the optically anisotropic layer 1 is placed on the surface of the optically anisotropic layer 1 on the surface of the optically anisotropic layer 1 which is different from the surface of the transparent support to which the antiglare layer is attached. side. Then, a commercially available acrylic adhesive (UV-3300, manufactured by Toagosei Co., Ltd.) was used for coating, and an air-cooled metal halide lamp (manufactured by EYEGRAPHICS Co., Ltd.) of 160 W/cm was used from the side of the dummy support. The ultraviolet rays of 100 mJ/cm ² were used to cure the adhesive, and a polarizing plate 1 having a dummy support of a thickness of 144.5 μm was obtained.

The polarizing plate 1 with the obtained dummy support can be conveyed and wound up without wrinkles. Moreover, it is known that it is possible to handle well after a period of time after winding up, and it is excellent in workability.

In addition to the optically anisotropic layer 1 attached to the dummy support of the above-described dummy support, after the dummy support is peeled off from the optically anisotropic layer 1, the surface of the optically anisotropic layer 1 is bonded to the polarizer. This was produced in the same manner as the polarizing plate 1 with the dummy support, and a polarizing plate 2 having a film thickness of 70.5 μm was produced. The obtained polarizing plate 2 was greatly curled on the side of the anti-glare layer, and wrinkles occurred during transportation and during winding.

1‧‧‧ polarizer

2‧‧‧Optical anisotropic layer

4‧‧‧Protective layer

5‧‧‧hard coating

6‧‧‧Transparent support

12‧‧‧Alignment layer

16‧‧‧false support

21‧‧‧Next layer 1

22‧‧‧Next layer 2

Claims (15)

A polarizing plate comprising, in order, an optically anisotropic layer, a polarizer, and a hard coat layer, wherein the optically anisotropic layer is a layer formed of a composition comprising a liquid crystal compound, and the optical anisotropic layer The polarizer includes only the adhesive layer 1 or only the adhesive layer 1 and a protective layer provided on the surface of the polarizer. The polarizing plate of claim 1, wherein a transparent support is included between the polarizer and the hard coat layer, and the hard coat layer directly contacts the transparent support. The polarizing plate of claim 2, wherein the transparent support comprises deuterated cellulose, a (meth)acrylic polymer, a cycloolefin polymer, or a polyester. The polarizing plate of claim 2, wherein only the bonding layer 2 is included between the transparent support and the polarizer. The polarizing plate of any one of claims 1 to 4, wherein the subsequent layer 1 is a layer formed of an active energy ray-curable adhesive. The polarizing plate according to any one of claims 1 to 4, wherein the optically anisotropic layer has a film thickness of 0.5 μm to 3 μm. The polarizing plate of any one of claims 1 to 4, wherein only the bonding layer 1 is included between the optically anisotropic layer and the polarizer. The polarizing plate of any one of claims 1 to 4, wherein between the optically anisotropic layer and the polarizer, only a bonding layer 1 and a protective layer disposed on a surface of the polarizing film are included, the protective layer comprising Deuterated cellulose, (meth)acrylic polymer, or cyclic olefin polymer. The polarizing plate according to any one of claims 1 to 4, which comprises a dummy support which is a layer formed by directly coating a composition containing a liquid crystal compound on the surface of the dummy support, or directly coated The layer formed by the alignment layer provided on the dummy support. A method of producing a polarizing plate according to any one of claims 1 to 8, the manufacturing method comprising: (1) preparing a transfer material comprising: a dummy support and an optical difference a directional layer having a brushed surface or an alignment layer provided on the surface, the optically anisotropic layer being directly coated on the brushed surface or the alignment layer by a composition comprising a liquid crystal compound a layer formed; (2) laminating the optically anisotropic layer on a film comprising a polarizer, directly or in addition to another layer; (3) after the film comprising the polarizer a hard coat layer is laminated on a surface opposite to the surface of the printing material; and (4) the dummy support is peeled off and separated from the optically anisotropic layer. The manufacturing method of claim 10, wherein in (2), the transfer material is directly followed by a surface of the optically anisotropic layer with respect to the dummy support as a film side including the polarizer The film including the polarizer is used, and (2) and (4) are carried out in this order. A method of manufacturing a polarizing plate, such as the polarizing plate of claim 9, the manufacturing method comprising: (1) preparing the following transfer material: The transfer material comprises a dummy support having a brushed surface or an alignment layer provided on the surface, the optically anisotropic layer being directly coated with a composition containing a liquid crystal compound. a layer formed on the brush-treated surface or the alignment layer; (12) a method of forming the transfer material on the side of the optically anisotropic layer with respect to the dummy support as a film side including a polarizer Directly following the film containing the polarizer; and (3) laminating the hard coat layer on the surface of the film including the polarizer opposite to the surface on which the transfer material is applied. The manufacturing method of claim 10, wherein the (2) is an active energy ray-curable adhesive, and the polarizer of the laminate obtained by laminating the transfer material on the film containing the polarizer is The surface on the side of the optically anisotropic layer is irradiated with an active energy ray. The manufacturing method of claim 12, wherein the (12) is an active energy ray-curable adhesive, and the polarizer of the laminate obtained by laminating the transfer material on the film containing the polarizer is The surface on the side of the optically anisotropic layer is irradiated with an active energy ray. The manufacturing method according to any one of claims 10 to 14, wherein the polarizer in the film comprising the polarizer and the optically anisotropic layer are directly followed.