TW201930083A - Laminate body for polarization plate, polarization plate, display device, and method for manufacturing polarization plate - Google Patents

Abstract

A laminate body including an unstretched polyvinyl alcohol resin film and a base material film, wherein the polyvinyl alcohol resin film has a phase difference Re1 in the in-plane direction of 50 nm or less and a thickness T of 45 [mu]m or less, the base material film is a film comprising a resin, the resin having a melt flow rate measured in specified conditions of 1 g/10 min or less and a tensile modulus of elasticity E of 50-1200 MPa, the phase difference Re2 in the in-plane direction of the stretched product of the base material film being 0-20 nm.

Description

Stacker for polarizing plate, polarizing plate, display device, and manufacturing method of polarizing plate

The present invention relates to a stack for a polarizing plate, a polarizing plate, a display device, and a method of manufacturing the polarizing plate.

Conventionally, display devices such as liquid crystal display devices and organic electroluminescence (EL) display devices have been required to have a large display area, a light weight, and a small thickness. Therefore, the panels constituting the display device have been required to be thinner in the past.

In the display device, a polarizing plate having a polarizing member and a protective film for protecting the polarizing member is generally used. In order to form a thin display device, a polarizing plate is also required to be thinner. In particular, since the polarizer sometimes shrinks in the use environment of the display device, such bending due to shrinkage may become a problem in a thin and large display device. Therefore, by using a thin polarizer having a thickness of 10 μm or less, in addition to the reduction in the thickness of the display device due to the reduction in the thickness of the polarizer itself, reduction in the occurrence of the aforementioned bending can be expected.

However, in the case where a polarizing material of such a thin polyvinyl alcohol is to be produced by a conventional manufacturing method, the melting of the polarizer frequently occurs. As a method of manufacturing such a polarizing plate that prevents the fuse from being blown and includes a thin polarizer, several methods have been proposed.

For example, in Patent Document 1, it is proposed to apply an aqueous solution containing a polyvinyl alcohol-based resin to an amorphous ester-based thermoplastic resin substrate, thereby producing a polyvinyl alcohol-based resin layer to form a stacked body, and to form a stacked body. After the stretching treatment of the body, the dichroic substance is oriented to form a colored stack, and the colored stacked body is subjected to elongation treatment to obtain an optical film.

"Patent Literature"
Patent Document 1: Japanese Patent No. 4691205 (corresponding publication: US Patent No. 8314987)

When a thin polarizing plate is produced by the method described in Patent Document 1, the stacked body is stretched at a high stretching ratio, and a phase difference occurs in the base film after the stretching treatment. In this case, since it is difficult to directly use the base film as the polarizing plate protective film, it is peeled off and discarded, so that a wasteful material is generated. Furthermore, it is possible to add a work for separately preparing a protective film for protecting the polarizing plate and attaching it to the polarizing plate.

In view of the above, it is an object of the present invention to provide a polarizing plate stack, a polarizing plate and a display device including the same, which can be used even if a base film is used as a protective film, and can be efficiently produced even if the thickness is thin. A method of manufacturing the aforementioned polarizing plate.

As a result of research conducted to solve the above problems, the inventors have found that by using an in-plane retardation and a thickness of a polyvinyl alcohol resin film within a specified range, and having a softness capable of extending at a high magnification at a low temperature The substrate film made of a resin solves the above problems and further completes the present invention.

Therefore, according to the present invention, the following [1] to [15] can be provided.

[1] A stack for a polarizing plate comprising a stack of polarizing plates of an unstretched polyvinyl alcohol resin film and a base film, wherein a phase difference Re1 of the in-plane direction of the polyvinyl alcohol resin film is 50 nm Hereinafter, the thickness T is 45 μm or less,
The base film is a film made of a resin.
The melting rate of the resin is 1 g/10 min or more, and the melt flow rate is measured at 190 ° C and a load of 2.16 kg.
The tensile elastic modulus E of the resin is 50 MPa or more and 1200 MPa or less.
The phase difference Re2 in the in-plane direction of the extension of the base film is 0 nm or more and 20 nm or less, and the phase difference Re2 is a free end of the stack for the polarizing plate at a temperature of 50 ° C to 120 ° C. The axis is extended to 6.0 times, and when the base film is formed as the extension, the extension has a phase difference.

[2] The stacked body for a polarizing plate according to the above [1], wherein the resin-based cycloolefin resin,
The cycloolefin-based resin contains a cycloolefin-based polymer.
The cycloolefin-based polymer is a block copolymer hydrogenated product obtained by hydrogenating the block copolymer [D], and the block copolymer [D] is composed of:
a polymer block [A] having a repeating unit [I] derived from an aromatic vinyl compound as a main component, and a repeating unit [I] derived from an aromatic vinyl compound and a chain conjugated diene compound The repeating unit [II] is a polymer block [B] as a main component, or a polymer block [C] having a repeating unit [II] derived from a chain conjugated diene compound as a main component.

[3] A stack for a polarizing plate comprising a stack of polarizing plates of an unstretched polyvinyl alcohol resin film and a base film, wherein a phase difference Re1 of the in-plane direction of the polyvinyl alcohol resin film is 50 nm Hereinafter, the thickness T is 45 μm or less,
The base film is a film made of a resin.
The above resin is a cyclic olefin resin,
The cycloolefin-based resin contains a cycloolefin-based polymer.
The cycloolefin-based polymer is a block copolymer hydrogenated product obtained by hydrogenating the block copolymer [D], and the block copolymer [D] is composed of:
a polymer block [A] having a repeating unit [I] derived from an aromatic vinyl compound as a main component, and a repeating unit [I] derived from an aromatic vinyl compound and a chain conjugated diene compound The repeating unit [II] is a polymer block [B] as a main component, or a polymer block [C] having a repeating unit [II] derived from a chain conjugated diene compound as a main component,
The phase difference Re2 in the in-plane direction of the extension of the base film is 0 nm or more and 20 nm or less, and the phase difference Re2 is a free end of the stack for the polarizing plate at a temperature of 50 ° C to 120 ° C. The axis is extended to 6.0 times, and when the base film is formed as the extension, the extension has a phase difference.

[4] The stack for polarizing plates according to [2], wherein the cycloolefin-based resin contains a plasticizer, a softener, or both.

[5] The above-mentioned plasticizer, the softener or both are selected from the group consisting of an ester plasticizer and an aliphatic hydrocarbon polymer.

[6] The stack for polarizing plates of any one of [1] to [5] wherein the resin contains an organometallic compound.

[7] The stack for polarizing plates according to any one of [1], wherein the base film is interposed with a binder layer and stacked on the polyvinyl alcohol resin film.

[8] A polarizing plate which is uniaxially stretched by the stack for a polarizing plate according to any one of [1] to [7].

[9] The polarizing plate according to [8], wherein a protective film or a binder is provided on a surface of the polarizing plate in which the polyvinyl alcohol resin film is not stacked with the base film.

[10] The polarizing plate according to [9], wherein the protective film is made of a resin selected from the group consisting of a cycloolefin resin, an acrylic resin, a polyethylene terephthalate resin, and a triacetyl cellulose resin.

[11] A display device comprising: a plurality of substrates, a liquid crystal layer interposed therebetween, and a polarizing plate according to any one of [8], wherein the polarizing plate is disposed in the two substrates. At least one outer side of the substrate.

[12] A display device comprising: a plurality of substrates, a light-emitting layer interposed therebetween, and a polarizing plate according to any one of [8], wherein the polarizing plate is disposed in the two substrates. The outside of a substrate.

[13] The display device according to [11], wherein a base film of the polarizing plate is provided between the polyvinyl alcohol resin film of the polarizing plate and the liquid crystal layer.

[14] The display device according to [12], wherein a base film of the polarizing plate is provided between the polyvinyl alcohol resin film of the polarizing plate and the light emitting layer.

[15] A method of producing a polarizing plate, comprising the step of uniaxially extending the stack for a polarizing plate according to any one of [1] to [7].

According to the present invention, it is possible to provide a stack for a polarizing plate which can be used even if a base film is used as a protective film, and which can be efficiently manufactured even if the thickness is thin, a polarizing plate and a display device using the same, and the use of the foregoing A method of manufacturing a polarizing plate of a stacked body.

The embodiments and examples are disclosed below to explain the present invention in detail. However, the present invention is not limited by the embodiments and the examples described below, and may be arbitrarily changed without departing from the scope of the invention and the scope of the invention.

In the present application, the term "long strip" means a length of 5 times or more with respect to the width of the film, preferably 10 times or more, and specifically means having a length The length of the degree of winding or storage in a roll. The upper limit of the ratio with respect to the length of the width of the film is not particularly limited, but is, for example, 100,000 times or less.

In the present application, the phase difference Re of the in-plane direction of the film and the phase difference Rth in the thickness direction are follows: Re=(nx-ny)×d and Rth={[(nx+ny)/2]-nz}×d And calculate. And the Nz coefficient of the film is a value represented by [(nx-nz)/(nx-ny)], and is also expressed as [(Rth/Re)+0.5]. Here, the refractive index (in-plane maximum refractive index) in the slow axis direction of the nx-based film, ny is the refractive index perpendicular to the in-plane direction of the slow axis in the plane of the film, and the thickness direction of the nz-based film The refractive index, the thickness (nm) of the d-type film. The wavelength is measured, unless otherwise noted, to a representative wavelength of 550 nm in the visible region.

[Implementation Type 1: Stacker and Polarizing Plate for Polarizing Plate]

Hereinafter, a stack for a polarizing plate according to an embodiment 1 of the present invention, a polarizing plate manufactured using the stacked body, and a method for manufacturing the same will be described with reference to FIGS. 1 to 4.

[1. Stack for polarizing plate]

The stacked body for a polarizing plate of the present invention (hereinafter also referred to simply as "stacked body") comprises an unstretched polyvinyl alcohol resin film and a base film. Fig. 1 is a cross-sectional view showing an example of a stack 10 of an embodiment 1 of the present invention. As shown in FIG. 1, the stacked body 10 of the present embodiment comprises an unstretched polyvinyl alcohol resin film 11 and a base film 12 provided on the polyvinyl alcohol resin film 11. In Fig. 1, a bonding agent of the polyvinyl alcohol resin film 11 and the base film 12 is bonded to the 13th. The stacked body 10 of the present invention is a material for manufacturing a polarizing member (polarizing plate).

[Polyvinyl alcohol resin film]

In the present invention, the polyvinyl alcohol resin film is a film having a phase difference Re1 in the in-plane direction of 50 nm or less and a thickness T of 45 μm or less. The polyvinyl alcohol resin film is an unstretched film made of a polyvinyl alcohol resin (hereinafter, "polyvinyl alcohol" is abbreviated as "PVA"). In the present application, the term "unstretched film" means a person who is not supplied with an extension processor.

In the present invention, the PVA resin film (polyvinyl alcohol resin film) is not necessarily limited, but in terms of availability, etc., it is produced by using saponification of polyvinyl acetate obtained by polymerizing vinyl acetate. It is better. The PVA contained in the PVA resin is preferably in the range of 500 to 8,000, and the degree of saponification is preferably 90 mol% or more from the viewpoint of excellent extensibility or polarizing performance of the polarizer which can be obtained. Here, the degree of polymerization is an average degree of polymerization measured in accordance with the description of JIS K6726-1994, and the degree of saponification is a value measured in accordance with the description of JIS K6726-1994. The polymerization degree is preferably in the range of 1,000 to 6,000, more preferably 1,500 to 4,000. The preferred range of saponification degree is 95 mol% or more, and more preferably 99 mol% or more. PVA can also be a copolymer or graft polymer of vinyl acetate with other monomers copolymerizable.

In the present invention, the method for producing the PVA resin film is not particularly limited, and it can be produced by any method such as a well-known method. Examples of the production method include a cast film forming method using a PVA solution in which a PVA is dissolved in a solvent, a wet film forming method (discharging into a poor solvent), and a dry-wet film forming method. A gel film forming method (a method in which a PVA aqueous solution is cooled and gelated, and a solvent is removed to obtain a PVA resin film), and a combination thereof. Another example of the production method is a melt extrusion film formation method in which a material obtained by melting a solvent containing PVA is used as a film forming stock solution. Among these, a resin film of PVA having high transparency and little coloration can be obtained by a casting film forming method and a melt extrusion film forming method, and a melt extrusion film forming method is preferred.

In the present invention, the PVA resin film is preferably contained in an amount of 0.01 to 30% by weight based on the PVA, such as a polyhydric alcohol such as glycerin, in order to improve mechanical properties or work smoothness in secondary processing, and to improve the operation. The surfactant or the film appearance or the like is preferably 0.01 to 1% by weight based on the surfactant containing an anionic surfactant or a nonionic surfactant with respect to PVA.

The PVA resin film may further contain an optional component such as an antioxidant, an ultraviolet absorber, a slip agent, a pH adjuster, an inorganic fine particle, a colorant, a preservative, a fungicide, a polymer compound other than the above components, and moisture. The PVA resin film may contain one or more of the above-mentioned optional components.

The thickness T of the PVA resin film is 45 μm or less, preferably 35 μm or less, preferably 25 μm or less, more preferably 20 μm or less, more preferably 5 μm or more, and preferably 10 μm or more. More preferably 15 μm or more. When the thickness of the PVA resin film is less than or equal to the upper limit of the above range, the contraction force of the polarizing plate can be effectively reduced, and a polarizing plate having sufficiently high polarizing performance can be obtained by being equal to or greater than the lower limit of the above range.

The phase difference Re1 of the PVA resin film in the in-plane direction is 50 nm or less, preferably 40 nm or less, preferably 30 nm or less, more preferably 20 nm or less, and preferably 0 nm or more, and 3 nm. The above is preferred. When the phase difference Re1 in the in-plane direction of the PVA resin film is equal to or less than the upper limit of the above range, the stacked body can be sufficiently stretched to obtain a polarizing plate having high polarizing performance.

The shape and size of the PVA resin film are appropriately adjusted to correspond to the intended use. In terms of manufacturing efficiency, the PVA resin film is preferably a long film.

[Substrate film]

The base film is a film formed of a resin, which is different from the layer of the PVA resin film. In the present invention, the resin forming the base film has a resin which can extend at a high elongation (for example, 6.0 times) at a low temperature (for example, 50 to 120 ° C). In the present invention, the resin-based melt flow rate of the base film is 1 g/10 minutes or more, and the resin (resin A) having a tensile modulus E of 50 MPa or more and 1200 MPa or less is included in the specification. A cycloolefin resin (resin B) of a cycloolefin polymer.

[Resin A]

In the present invention, the flow rate of the resin A forming the base film is 1 g/10 minutes or more, preferably 3 g/10 minutes or more, more preferably 5 g/10 minutes or more, and 300 g/ It is preferably 10 minutes or less, preferably 100 g/10 minutes or less. The melt flow rate described herein is a value measured at 190 ° C and a load of 2.16 kg. Hereinafter, only the "melt flow rate measured at 190 ° C and a load of 2.16 kg" is referred to as "MFR". When the MFR of the resin A is at least the lower limit value, the phase difference can be lowered when the polarizing plate is formed, and the heat resistance can be improved by setting the MFR to the upper limit or less.

The MFR of Resin A was measured in accordance with JIS-K-7210 using a melt flow indexer (MELT INDEXER) at a temperature of 190 ° C and a load of 2.16 kg.

In the present invention, the resin A forming the base film has a tensile elastic modulus E of 50 MPa or more, preferably 100 MPa or more, more preferably 200 MPa or more, and 1200 MPa or less, and 1000 MPa or less. Preferably, it is preferably 800 MPa or less. When the tensile elastic modulus E of the resin A is at least the lower limit value, the phase difference of the base film can be reduced when the stacked body is formed into a polarizing plate, and the upper limit can be made lower than the upper limit. The occurrence of breakage of the substrate film is prevented when the stacked body is extended.

The resin A which forms the base film is not particularly limited as long as it has a MFR of 1 g/10 min or more and a tensile elastic modulus E of 50 MPa or more and 1200 MPa or less, and is transparent as such a resin. The cycloolefin type resin containing a cycloolefin type polymer is preferable in that it is excellent in the property and the water vapor barrier property.

As the cycloolefin-based polymer, a block copolymer [D] obtained by hydrogenating the block copolymer [D] is preferred, and the block copolymer [D] is obtained by repeating from an aromatic vinyl compound. The polymer block [A] having the unit [I] as a main component and the repeating unit [I] derived from the aromatic vinyl compound and the repeating unit [II] derived from the chain conjugated diene compound as a main component The polymer block [B] or a polymer block [C] having a repeating unit [II] derived from a chain conjugated diene compound as a main component. Examples of such a block copolymer hydride include WO2000/32646, WO2001/081957, Japanese Patent Publication No. 2002-105151, Japanese Patent Publication No. 2006-195242, and Japanese Patent Publication No. 2011- A polymer described in, for example, No. 13378 and WO2015/002020.

[Resin B]

In the present invention, the resin B forming the base film is a cycloolefin resin containing a cycloolefin polymer. The cycloolefin-based polymer contained in the resin B is a hydrogenated block copolymer obtained by hydrogenating the block copolymer [D], and the block copolymer [D] is obtained by repeating from an aromatic vinyl compound. The polymer block [A] having the unit [I] as a main component and the repeating unit [I] derived from the aromatic vinyl compound and the repeating unit [II] derived from the chain conjugated diene compound as a main component The polymer block [B] or a polymer block [C] having a repeating unit [II] derived from a chain conjugated diene compound as a main component. As the hydride of the block copolymer, the same as "the hydride of the precursor block copolymer which can be suitably used as the resin A" can be used.

The resin B forming the base film may be a resin having an MFR of 1 g/10 min or more and a tensile elastic modulus E of 50 MPa or more and 1200 MPa or less.

[Plasticizers and Softeners]

In the present invention, the resin (resin A and resin B) forming the base film preferably contains a plasticizer and/or a softener (either or both of a plasticizer and a softener). By containing a plasticizer and/or a softening agent, the phase difference generated in the substrate film when the polarizing plate is obtained by extending the stacked body can be reduced.

As the plasticizer and the softener, those which can be uniformly dissolved or dispersed to form a base film are used. Specific examples of the plasticizer and the softener include an ester-based plasticizer composed of a polyhydric alcohol and a monocarboxylic acid (hereinafter referred to as a "polyol ester-based plasticizer"), and a polycarboxylic acid and a polycarboxylic acid. An ester-based plasticizer such as an ester-based plasticizer (hereinafter referred to as "polycarboxylic acid ester-based plasticizer"), a phosphate-based plasticizer, a sugar ester-based plasticizer, and other polymerizations Softener.

The example of the polyol which is a raw material of the ester-based plasticizer which is preferably used in the present invention is not particularly limited, but ethylene glycol, glycerin or trimethylolpropane is preferred.

Examples of the polyol ester-based plasticizer include a glycol ester-based plasticizer, a glyceride-based plasticizer, and other polyol ester-based plasticizers.

Examples of the polycarboxylic acid ester-based plasticizer include a dicarboxylic acid ester plasticizer and other polycarboxylic acid ester plasticizers.

Specific examples of the phosphate ester plasticizer include alkyl phosphates such as triethyl decyl phosphate and tributyl phosphate; cycloalkyl phosphates such as tricyclopentyl phosphate and cyclohexyl phosphate; and triphenyl phosphate. An aryl phosphate such as an ester or a tricresyl phosphate.

Specific examples of the sugar ester plasticizer include glucose pentaacetate, glucose pentapropionate, glucose pentabutyrate, sucrose octaacetate, sucrose octacarboxylate, and the like. Sucrose octaacetate is preferred.

Specific examples of the polymer softener include an aliphatic hydrocarbon polymer, an alicyclic hydrocarbon polymer, polyethyl acrylate, polymethyl methacrylate, methyl methacrylate and -2-hydroxy methacrylate. Acrylic polymer such as copolymer of ethyl ester, methyl methacrylate and copolymer of methyl acrylate and 2-hydroxyethyl methacrylate; polyvinyl isobutyl ether, poly-N-ethylene hydropyrrolidone Ethylene polymer; styrene polymer such as polystyrene or poly-4-hydroxystyrene; polyester such as polybutylene succinate, polyethylene terephthalate or polyethylene naphthalate Polyethers such as polyethylene oxide and polypropylene oxide; polyamines, polyurethanes, polyureas, and the like.

Specific examples of the aliphatic hydrocarbon polymer include low molecular weight substances such as polyisobutylene, polybutene, poly-4-methylpentene, poly-1-octene, and ethylene-α-olefin copolymer. a hydride; a low molecular weight substance such as a polyisoprene, a polyisoprene-butadiene copolymer, a hydride thereof, or the like. The aliphatic hydrocarbon-based polymer preferably has a number average molecular weight of from 300 to 5,000 from the viewpoint of being easily dissolved uniformly or even dispersed to a cycloolefin resin.

These polymer softeners may be homopolymers of one type of repeating unit or copolymers having a plurality of repeating structures. Further, the above polymers may be used in combination of two or more kinds.

In the present invention, the plasticizer and/or the softening agent are particularly excellent in compatibility with the resin forming the base film, and one or more selected from the group consisting of an ester plasticizer and an aliphatic hydrocarbon polymer. good.

The ratio of the plasticizer and/or softener (hereinafter also referred to as "plasticizer" or the like) in the base film is preferably 0.2 parts by weight or more based on 100 parts by weight of the resin forming the base film. It is preferably 0.5 parts by weight or more, more preferably 1.0 part by weight or more, more preferably 50 parts by weight or less, and still more preferably 40 parts by weight or less. By setting the ratio of the plasticizer or the like within the above range, even if the manufacturing process of the polarizing plate including the stretching treatment is carried out, the substrate film can be made sufficiently inferior in phase difference.

[Organic Metal Compounds]

In the present invention, the substrate film preferably contains an organometallic compound. By including the organometallic compound, the occurrence of peeling of the substrate film in the case where the stacked body is stretched at a high stretching ratio (for example, wet stretching at a stretching ratio of 6.0) can be more effectively suppressed.

The organometallic compound is a compound containing at least one of a chemical bond between a metal and carbon and a chemical bond between a metal and oxygen, and is a metal compound having an organic group. Examples of the organometallic compound include an organic ruthenium compound, an organic titanium compound, an organoaluminum compound, and an organic zirconium compound. Among these, an organic ruthenium compound, an organic titanium compound, and an organic zirconium compound are preferred, and an organic ruthenium compound is preferred because it is excellent in reactivity with polyvinyl alcohol. The organometallic compound may be used alone or in combination of two or more.

The organometallic compound is, for example, an organic ruthenium compound represented by the following formula (1), but is not limited thereto.
R ¹ _a Si(OR ² ) _3−a (1)
(In the formula (1), R ¹ and R ² are each independently selected from a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms, an epoxy group, an amine group, a decyl group, an isocyanate group, and a carbon atom. A group of groups of 1 to 10 organic groups, and a represents an integer of 0 to 3.)

In the formula (1), a preferred example is as R ¹ , and examples thereof include an epoxy group, an amine group, a decyl group, an isocyanate group, a vinyl group, an aryl group, an acryl group, and a carbon number of 1 to 8. The alkyl group, -CH ₂ OC _n H _{2n + 1} (n represents an integer of 1-4), and the like.

Further, in the formula (1), a preferable example is as R ² , and examples thereof include a hydrogen atom, a vinyl group, an aryl group, an acryl fluorenyl group, an alkyl group having 1 to 8 carbon atoms, and -CH ₂ OC _{n .} H _{2n + 1} (n represents an integer of 1 to 4).

Examples of the organic ruthenium compound include epoxy-based organic ruthenium compounds such as 3-glycidoxypropyltrimethoxydecane and 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane. An amine-based organic ruthenium compound such as 3-aminopropyltrimethoxydecane or N-2-(aminoethyl)-3-aminopropyltrimethoxydecane, or isocyanuric acid (trimethoxydecyl) An isocyanate-based organic ruthenium compound such as an isocyanate-based organic ruthenium compound such as a propyl) ester or an oxime-based organic ruthenium compound such as 3-mercaptopropyltrimethoxydecane or 3-isocyanatopropyltriethoxydecane.

Examples of the organic titanium compound include titanium alkoxide such as tetraisopropyl titanate, titanium chelate compound such as titanium acetylacetonate, and titanium oxytitanate such as titanium isostearate.

Examples of the organic zirconium compound include zirconium alkoxide such as n-propyl zirconate, zirconium chelate such as zirconium tetraacetate acetone, and zirconium zirconium oxide such as zirconium stearate.

Examples of the organoaluminum compound include an alkane alumina such as secondary butyl alumina and an aluminum chelate compound such as aluminum triacetate.

The proportion of the organometallic compound in the base film is preferably 0.005 parts by weight or more, more preferably 0.01 parts by weight or more, more preferably 0.03 parts by weight or more, based on 100 parts by weight of the resin forming the base film. On the other hand, it is preferably 1.0 part by weight or less, more preferably 0.5 part by weight or less. By setting the ratio of the organometallic compound within the above range, the occurrence of peeling of the substrate film in the case of wet-extending the stacked body at a high magnification (for example, elongation ratio of 6.0) can be more effectively suppressed.

[arbitrary ingredients]

The base film may contain other optional components in addition to the resin, the plasticizer, the organometallic compound, and the like. Examples of the optional component include stabilizers such as antioxidants, ultraviolet absorbers, and light stabilizers; resin modifiers such as slip agents; colorants such as dyes and pigments; and antistatic agents. These admixtures may be used singly or in combination of two or more kinds, and the blending amount thereof may be appropriately selected within the range not impairing the object of the present invention.

[Method for Producing Substrate Film]

The base film is produced by forming a composition (respectively referred to as "resin composition") containing a component for forming a base film (resin and a component added as required) into a film shape by an arbitrary molding method. .

Examples of the method of forming the resin composition into a film shape include a casting method, a extrusion molding method, and an inflation molding method.

The thickness of the base film is preferably 1 μm or more, more preferably 3 μm or more, and most preferably 50 μm or less, and preferably 20 μm or less. When the thickness of the base film is at least the lower limit of the above range, the melting of the polarizer in the polarizing plate process can be effectively prevented, and the extended stack can be reduced by being equal to or less than the upper limit of the above range. The phase difference generated in the substrate film when the polarizing plate is obtained.

[Manufacturing method of stack]

Fig. 2 is a schematic view showing an example of a manufacturing apparatus 200 of a stacked body according to the present embodiment. The manufacturing apparatus 200 is provided with the winding-out apparatus 201 & 202, the bonding apparatus 205, and the winding apparatus 203.

As shown in FIG. 2, the PVA resin film 11 taken out from the unwinding device 201 is transported to the bonding device 205, and the bonding agent is applied to the bonding device 205, and then the substrate film 12 is unwound from the winding device 202. The laminate 10 can be obtained by fitting. The manufactured stack 10 can be wound into a roll shape by the winding device 203 for further processing.

The bonding agent 13 for bonding the PVA resin film 11 and the base film 12 is not particularly limited, and examples thereof include an acrylic adhesive, an urethane adhesive, a polyester adhesive, and a polyvinyl alcohol. A bonding agent, a polyolefin-based bonding agent, a modified polyolefin-based bonding agent, a polyvinyl alkyl ether-based bonding agent, a rubber-based bonding agent, a vinyl chloride-vinyl acetate-based bonding agent, and SEBS (styrene-ethylene-butyl) Ethylene-styrene copolymer), vinyl binder such as ethylene-styrene copolymer, ethylene methyl (meth) acrylate copolymer, ethylene ethyl (meth) acrylate copolymer, etc. An acrylate-based bonding agent or the like. In order to more effectively suppress the occurrence of peeling of the PVA resin film 11 and the base film 12 in the case of wet-extending the stack at a high magnification (for example, stretch ratio of 6.0), it is preferred to use a bonding agent.

The "surface on which the base film 12 is attached to the PVA resin film" or "the surface on which the PVA resin film is attached to the base film 12" may be subjected to corona treatment, saponification treatment, primer treatment, anchoring. Easy bonding treatment such as coating treatment.

[stack]

In the present invention, Re2 is 0 nm or more and 20 nm or less. Re2 is preferably 0 nm or more, and preferably 10 nm or less, and preferably 5 nm or less. When Re2 is equal to or less than the upper limit, the phase difference which appears on the base film when the stacked body 10 is extended to form a polarizing plate can be reduced.

Re2 is uniaxially extended to 6.0 times the free end of the stack 10 at a temperature of 50 ° C to 120 ° C, and the extension of the substrate film is obtained when the substrate film in the stack is formed into an extension. The phase difference in the in-plane direction. That is, Re2 is not the phase difference of the substrate film itself in the stack, but is a phase difference generated in the extension of the substrate film after a specific stretching treatment is applied to the stacked body.

The extension temperature for obtaining such an extension may be any temperature in the range of 50 °C to 120 °C. Thus, a number of operating conditions for obtaining an extension of the extension are contemplated. In the case where the extension exhibits a phase difference of 0 nm or more and 20 nm or less in any of a plurality of operating conditions, the stack satisfies the above requirements.

However, it is preferable that the extension exhibits a phase difference of 0 nm or more and 20 nm or less due to all of the plurality of operating conditions obtained. In this case, in the manufacture of the polarizing plate which is passed through the stacked body for a polarizing plate of the present invention, the degree of freedom in setting the high elongation condition can be obtained.

In general, in this temperature range, when the extension temperature is low, a large phase difference appears. Therefore, as long as the "phase difference between the extensions formed by the extension of 50 ° C" and the "phase difference of the extensions formed by the extension of 120 ° C" are in the range of 0 nm or more and 20 nm or less, It is judged that the extension exhibits a phase difference of 0 nm or more and 20 nm or less due to all of the aforementioned plurality of operating conditions.

The stacked body 10 of the present invention is a material for manufacturing a polarizing plate. The stacked body is subjected to a predetermined process such as elongation processing and dyeing treatment, and is then formed into a polarizing plate. The polarizing plate of the present invention produced by using the stacked body 10 of the present embodiment will be described below.

[2. Polarizer]

The polarizing plate 100 of the present invention is obtained by uniaxially stretching the stacked body 10 of the present embodiment. 3 is a schematic cross-sectional view showing a polarizing plate 100 manufactured using the stacked body 10 of the present embodiment.

As shown in FIG. 3, in the polarizing plate 100, a base film 112 is stacked on one surface (the upper side in the figure) of the PVA resin film 111. In Fig. 3, 113 is a bonding agent layer.

[Method of Manufacturing Polarizing Plate]

A method of manufacturing a polarizing plate using a stacked plate according to Embodiment 1 of the present invention will be described. 4 is a schematic view showing an example of a manufacturing apparatus 300 for manufacturing the polarizing plate 100 using the stacked body 10 according to the present embodiment.

As shown in FIG. 4, the manufacturing apparatus 300 includes the unwinding apparatuses 301 & 307, the processing apparatuses 302-305, the drying apparatus 306 & 309, the bonding apparatus 308, and the winding apparatus 310.

The method for producing a polarizing plate of the present invention includes a step of stretching a stack of the present invention uniaxially (extension processing step). The method for producing a polarizing plate of the present invention may further include a dyeing treatment step of dyeing the stacked body and/or a drying step of drying the stacked body. In the present embodiment, the stacked body 10 taken out from the unwinding device 301 is transported to the processing apparatuses 302 to 305, and a dyeing process (dyeing process) for dyeing the PVA resin film of the stacked body is performed, and the stacked body is uniaxially Extended extension processing (extension processing), and specified processing. The polarizing plate 100 can be obtained by performing a process (drying process) of "drying the stacked body after the treatment is performed in the drying device 306". Each step will be described in detail below.

[Extension processing procedure]

In the present embodiment, the stretching treatment step is a step of uniaxially stretching the stack. The method of extending the stacked body is not particularly limited, but it is preferably wet-extended. The stretching step can be carried out once or twice or more.

The stretching ratio of the stacked body is preferably 5.0 or more, more preferably 5.5 or more, and most preferably 7.0 or less, and more preferably 6.5 or less. When the stretching ratio of the stacked body is set to be equal to or less than the upper limit of the above range, even in the manufacturing process of the polarizing plate including the stretching treatment, the phase difference of the base film can be reduced, and the occurrence of breakage of the polarizing plate can be prevented. When the stretching ratio is set to be equal to or higher than the lower limit of the above range, a polarizing plate having sufficient polarizing performance can be obtained. In the case where the stacking of the stack is performed twice or more, it is preferable that the total stretch ratio represented by the product of the respective stretch ratios is as long as possible.

The stretching temperature of the stacked body is not particularly limited, but is preferably 30° C. or higher, preferably 40° C. or higher, more preferably 50° C. or higher, and preferably 140° C. or lower, and 90° C. or lower. Good, especially below 70 °C. The elongation can be smoothly performed by extending the temperature to be equal to or higher than the lower limit of the above range, and effective stretching can be performed by extending the extension below the upper limit of the above range. The range of the extension temperature is preferably any of a dry extension method and a wet extension method, but it is preferably a wet extension.

The stacking process may be performed by any of the following: a longitudinal stretching process extending along the longitudinal direction of the film, a lateral stretching process extending along the width direction of the film, and a process of neither parallel nor perpendicular to the width direction of the film. An oblique extension process that extends obliquely. The extension of the stack is preferably uniaxially extended at the free end, preferably uniaxially extending at the free end of the longitudinal direction.

[Dyeing process]

The dyeing treatment step is a step of dyeing the PVA resin film of the stack. In the present embodiment, the method for producing a polarizing plate includes a dyeing treatment (step) of dyeing the PVA resin film of the stacked body. However, in the present invention, the dyeing treatment may be arbitrary or may not be included. The dyeing treatment step can also be carried out before the elongation treatment. Further, the dyeing of the PVA resin film can also be carried out for the PVA resin film before the formation of the stacked body.

Examples of the dyeing of the PVA resin film in the dyeing treatment step include dichroic materials, and examples of the dichroic material include iodine and an organic dye. The dyeing method using these dichroic substances is arbitrary. For example, the layering of the PVA resin film may be performed by dipping the layer of the PVA resin film by a dyeing solution containing a dichroic substance. Further, when iodine is used as the dichroic substance, the dyeing solution may contain an iodide such as potassium iodide from the viewpoint of improving the dyeing efficiency. The dichroic substance is not particularly limited. However, when a polarizing plate is used for a display device for a vehicle, an organic dye is preferable as the dichroic substance.

[Drying process]

The drying step is a step of drying the stacked body through the treatment steps such as the dyeing treatment step and the elongation treatment step. In the drying step, it is preferred to dry the stack after the treatment step in a dryer having a temperature of 50 ° C to 100 ° C for 0.5 minutes to 10 minutes. The drying temperature of the above-mentioned stacked body is preferably 60 ° C or higher, and preferably 90 ° C or lower. By setting the drying temperature to the lower limit or lower, the drying time can be shortened, and by setting the drying temperature to the upper limit or lower, cracking of the PVA resin film can be prevented. The drying time of the above-mentioned stacked body is preferably 1 minute or more, and preferably 5 minutes or less. By setting the drying time to the lower limit or more, the stacked body can be sufficiently dried, and by setting it to the upper limit or less, cracking of the PVA resin film in the stacked body can be prevented.

In the polarizing material of the film made only of the conventional PVA resin, cracking may occur after the drying process. However, the polarizing plate of the present embodiment is manufactured by using a stack including a PVA resin film and a base film. Therefore, the occurrence of cracking of the polarizer can be suppressed even after the drying process.

[Characteristics of layers in polarizing plates]

The thickness of the PVA resin film in the polarizing plate is preferably 20 μm or less, more preferably 10 μm or less, more preferably 3 μm or more, and most preferably 5 μm or more. When the thickness is equal to or less than the upper limit, the thickness of the polarizing plate can be reduced, and by the thickness being less than or equal to the lower limit, a polarizing plate having sufficiently high polarizing performance can be obtained.

The phase difference in the in-plane direction of the base film in the polarizing plate is preferably 20 nm or less, more preferably 15 nm or less, still more preferably 10 nm or less, and more preferably 0 nm or more. When the phase difference in the in-plane direction of the base film in the polarizing plate is within the above range, the black shift when the polarizing plate is mounted on the liquid crystal display device can be suppressed.

[3. The effect and effect of this embodiment]

In the present embodiment, the PVA resin film including "the phase difference Re1 having a small in-plane direction and a small thickness" and the "resin made of a resin having a flexibility capable of extending at a high rate at a low temperature" are used. The stack of the material film is extended to manufacture a polarizing plate, so that even when the stacked body is stretched at a high magnification at a low temperature, the occurrence of the melting of the PVA resin film can be suppressed, and the phase in the extended base film can be suppressed. Poor appearance. As a result, according to the present embodiment, the base film can be used as a protective film without peeling off the base film and directly serving as a protective film on one side of the PVA resin film, and the waste material can be reduced. A method of manufacturing a polarizing plate that can be used efficiently and can be efficiently produced even if the thickness is thin.

[Modification 1]

Hereinafter, a polarizing plate 120 according to a modification 1 manufactured by the stacked body 10 according to the first embodiment of the present invention will be described with reference to Figs. 4 and 5 .

Fig. 5 is a schematic cross-sectional view showing a polarizing plate 120 of a modification 1 manufactured by using the stacked body 10 according to the embodiment of the present invention. In the polarizing plate 120, as shown in FIG. 5, a base film 112 is stacked on one surface (the upper side surface of the figure) of the PVA resin film 111 on the other side of the PVA resin film 111 (illustrated The lower side) is stacked with a protective film 115. In Fig. 5, 113 and 114 are bonding agent layers. The bonding agent for bonding the protective film 115 to the PVA resin film can be the same as the bonding agent for bonding the base film to the PVA resin film.

The method for producing the polarizing plate 120 according to the present embodiment includes the step of bonding the PVA resin film 111 of the polarizing plate 100 obtained in the first embodiment to the protective film 115 directly or via an intermediate bonding agent.

Specifically, as shown in FIG. 4, the polarizing plate 100 of the first embodiment is transported to the bonding apparatus 308, and the bonding agent 114 is applied to the surface of the PVA resin film 111 on the side where the base film 112 is not stacked. The protective film 115 rolled out by the device 307 is bonded to each other, whereby the polarizing plate 120 having the protective film 115 is obtained. The polarizing plate 120 manufactured can be wound up by the winding device 310 into a shape of a roll for further processing.

In the present embodiment, as the protective film 115, a film made of a resin selected from the group consisting of a cycloolefin resin, an acrylic resin, a polyethylene terephthalate resin, and a triacetyl cellulose resin can be used.

The polarizing plate of the present embodiment is similar to the polarizing plate of the first embodiment in that the PVA resin film including "the phase difference Re1 in the in-plane direction is small and has a small thickness" and "the soft film having a high magnification at a low temperature" The stack of the base film formed of the resin is stretched to produce a polarizing plate, and thus has the same operational effects as those of the first embodiment.

Further, according to the present example, the surface of the PVA resin film 111 on the side of the unstacked base film 112 is provided with the protective film 115, so that the surface of the PVA resin film 111 is prevented from being scratched.

[Modification 2]

Next, a polarizing plate 130 according to a second modification manufactured by the stacked body 10 according to the first embodiment of the present invention will be described with reference to Fig. 6 .

Fig. 6 is a schematic cross-sectional view showing a polarizing plate of a second modification produced by using the stacked body 10 according to the first embodiment of the present invention.

FIG. 6 is a schematic cross-sectional view showing the polarizing plate 130 of the present example. In the polarizing plate 130, as shown in FIG. 6, a base film 112 is stacked on one surface (the upper side surface of the figure) of the PVA resin film 111 on the other side of the PVA resin film 111 (illustrated The lower side) is stacked with an adhesive layer 116.

The method for producing the polarizing plate 130 according to the present embodiment includes the step of providing the adhesive layer 116 to the PVA resin film 111 of the polarizing plate 100 obtained in the first embodiment.

As the binder forming the adhesive layer 116, various commercially available adhesives such as a binder containing a polymer of an acrylic polymer as a main component are used.

In the polarizing plate 130 of the present embodiment, for example, the PVA of the polarizing plate 100 of the embodiment 1 can be transferred by a commercially available film having a binder layer (for example, "MASTACK Series" manufactured by Fujimori Industry Co., Ltd.). The surface of the resin film 111 on the side of the base film 112 is not stacked, and is formed by forming a binder layer.

The polarizing plate 130 of the present embodiment is also the same as the polarizing plate of the first embodiment, and is formed by a PVA resin film having a small phase difference Re1 and a small thickness in the in-plane direction and having a high magnification at a low temperature. Since the stacked body of the flexible resin base film is stretched to produce a polarizing plate, it has the same operational effects as in the first embodiment.

Further, according to the present example, the surface of the PVA resin film 111 on the side where the base film 112 is not stacked is provided with the adhesive layer 116, so that the surface of the PVA resin film 111 is prevented from being scratched.

[Implementation 2: Stacker for polarizing plate and polarizing plate]

Referring to FIG. 7 and FIG. 8 , a stack 15 (a stack for a polarizing plate) of an embodiment 2 of an embodiment of the present invention, and a polarizing plate 150 manufactured using the stacked body 15 and a method of manufacturing the same are described. . The same structures and aspects as those of the embodiment 1 are denoted by the same reference numerals, and the description thereof will be omitted.

7 is a cross-sectional view showing a stacked body 15 according to an embodiment 2 of the present invention, and FIG. 8 is a schematic cross-sectional view showing a polarizing plate 150 manufactured using the stacked body 15 of the present embodiment.

[stack]

The stacked body 15 of the present embodiment is different from the stacked body of the embodiment 1 in that the base film 12 is directly stacked on the PVA resin film 11.

As a method of directly stacking the base film 12 to the PVA resin film 11, for example, methods such as thermal fusion, ultrasonic fusion, and laser fusion can be mentioned. In the present application, the base film which is "directly stacked" on the surface of the PVA resin film includes a case where a PVA resin film and a base film are separately prepared and directly bonded to each other without interposing another layer. .

The stacked body 15 of this embodiment is also the same as the stacked body 10 of the embodiment 1, and can be used as a material for manufacturing a polarizing plate.

[Polarizer]

The polarizing plate 150 of the present invention produced by using the stacked body 15 of the present embodiment will be described below. The polarizing plate 150 can be obtained by uniaxially stretching the stacked body 10 of the present embodiment.

As shown in FIG. 8, in the polarizing plate 150, a base film 112 is directly stacked on one side (the upper side in the figure) of the PVA resin film 111. The polarizing plate 150 of this embodiment can also be manufactured by the same method as the polarizing plate 100 of the first embodiment.

[Effects of this embodiment]

In the present embodiment, as in the case of the polarizing plate of the embodiment 1, the PVA resin film including "the phase difference Re1 in the in-plane direction is small and the thickness is small" and "the film has a high magnification at a low temperature." Since the stacked body of the flexible resin base film is stretched to manufacture the polarizing plate 150, it has the same operational effects as those of the first embodiment.

Further, according to the present embodiment, since the base film 12 is directly stacked to the stack of the PVA resin film 11, the fracture suppressing effect is excellent, and the environmental pollution caused by other substances in the production environment is also prevented, or Prevent the effect on the product (mixing foreign matter).

[Modification 3]

Next, a polarizing plate 160 according to a third modification manufactured by the stacked body 15 according to the embodiment 2 of the present invention will be described with reference to Fig. 9 . Fig. 9 is a schematic cross-sectional view showing a polarizing plate 160 of a third modification produced by using the stacked body according to the embodiment 2 of the present invention.

In the polarizing plate 160, as shown in FIG. 9, a base film 112 is stacked on one side (the upper side in the figure) of the PVA resin film 111 on the other side of the PVA resin film 111 (under the figure) The protective film 115 is stacked on the side of the intermediate bonding layer 114. The bonding agent 114 to which the protective film 115 is bonded to the PVA resin film 111 can be the same as the bonding agent which is bonded to the PVA resin film-bonding base film described in the first embodiment.

The method for producing the polarizing plate 160 according to the present embodiment includes the step of bonding the protective film 115 to the PVA resin film 111 of the polarizing plate 150 obtained in the second embodiment. The protective film 115 and the method of bonding the protective film are the same as those of the first modification.

The polarizing plate 160 of the present embodiment is also the same as the polarizing plate of the first embodiment, and is formed by a PVA resin film containing "the phase difference Re1 in the in-plane direction and a small thickness" and "having a high magnification at a low temperature." Since the stacked body of the flexible resin base film is stretched to produce a polarizing plate, it has the same operational effects as in the first embodiment.

Further, according to the present example, since the base film 12 is directly stacked to the stack 15 of the PVA resin film 11, the fracture suppressing effect is excellent, and the environmental pollution caused by other substances in the production environment is prevented, or prevented. The effect on the product (mixed with foreign matter).

According to the present example, the surface of the PVA resin film 111 on the side of the unstacked base film 112 is provided with the protective film 115, so that the surface of the PVA resin film 111 is prevented from being scratched.

[Modification 4]

Next, a polarizing plate 170 according to a fourth modification manufactured by the stacked body 15 according to the embodiment 2 of the present invention will be described with reference to FIG. Fig. 10 is a schematic cross-sectional view showing a polarizing plate 170 of a modification 4 produced by using the stacked body according to the embodiment 2 of the present invention.

In the polarizing plate 170, as shown in FIG. 10, a base film 112 is stacked on one side (the upper side in the figure) of the PVA resin film 111 on the other side of the PVA resin film 111 (illustrated The side layer) is stacked with an adhesive layer 116.

The method for producing the polarizing plate 170 according to the present embodiment includes the step of providing the adhesive layer 116 on the PVA resin film 111 of the polarizing plate 150 obtained in the second embodiment.

The method of forming the adhesive layer 116 and the adhesive for forming the adhesive layer 116 are the same as those of the second modification.

The polarizing plate 170 of the present embodiment is also the same as the polarizing plate of the first embodiment, and is formed by a PVA resin film containing "the phase difference Re1 in the in-plane direction and a small thickness" and "having a high magnification at a low temperature." Since the stacked body of the flexible resin base film is stretched to produce a polarizing plate, it has the same operational effects as in the first embodiment.

Further, according to the present example, since the base film 12 is directly stacked to the stack 15 of the PVA resin film 11, the fracture suppressing effect is excellent, and the environmental pollution caused by other substances in the production environment is prevented, or prevented. The effect of contaminating the product (mixing foreign matter).

Further, according to the present example, the surface of the PVA resin film 111 on the side where the base film 112 is not stacked is provided with the adhesive layer 116, so that the surface of the PVA resin film 111 is prevented from being scratched.

[Implementation 3: Display device]

The polarizing plate produced by using the stacked body for a polarizing plate of the present invention can be used as a material of a liquid crystal display device.

In general, the liquid crystal display device includes a light source, a light source side polarizing plate, a liquid crystal cell, and a viewing side polarizing plate in this order, but the polarizing plate obtained by the present invention can be used for any of the light source side polarizing plate and the viewing side polarizing plate. .

Examples of the driving method of the liquid crystal cell include a planar switching (IPS) mode, a vertical alignment (VA) mode, a multi-region vertical alignment (MVA) mode, a continuous flame-like arrangement (CPA) mode, and a hybrid arrangement nematic (HAN). Mode, twisted nematic (TN) mode, super twisted nematic (STN) mode, optically compensated birefringence (OCB) mode, etc.

Next, a display device 400 according to an embodiment 3 of the "polarizing plate 100 manufactured using the stacked body 10 of the present invention" will be described with reference to FIG. The display device 400 of the present embodiment is manufactured by stacking the polarizing plate 100 of the first embodiment as a light source side polarizing plate and a viewing side polarizing plate, and stacking them on a liquid crystal panel.

Figure 11 is a cross-sectional view showing a display device 400 according to an embodiment 3 of the present invention. As shown in FIG. 11, the display device 400 has two substrates 410 & 420, a liquid crystal layer 430 interposed therebetween, and polarizing plates 100 & 100 disposed on the outer sides of the two substrates 410 & 420 . The two polarizing plates 100 are stacked using the embodiment 1. The polarizing plate 100 manufactured by the body 10. As shown in FIG. 11, the two polarizing plates 100 are stacked such that the base film 112 of the polarizing plate is disposed between the PVA resin film 111 of the polarizing plate and the liquid crystal layer 430.

According to the present embodiment, it is possible to provide a display device including "a polarizing plate which can be used even if the base film is used as a protective film and can be efficiently produced even if the thickness is thin."

[Implementation type 4: display device]

Referring to Fig. 12, a display device 450 according to an embodiment 4 of the polarizing plate of the present invention will be described. The display device 450 of the present embodiment is manufactured by using the polarizing plate of the present invention as one of a light source side polarizing plate and a viewing side polarizing plate, and stacking the polarizing plate to a liquid crystal panel.

FIG. 12 is a cross-sectional view showing a display device 450 according to an embodiment 4 of the present invention. As shown in FIG. 12, the display device 450 has two substrates 410 & 420, a liquid crystal layer 430 interposed therebetween, and a polarizing plate 120 disposed on the outer surface (the side surface shown below) of the lower substrate 410. The polarizing plate 120 is a polarizing plate of Modification 1. As shown in FIG. 12, the polarizing plate 120 is stacked such that the base film 112 of the polarizing plate is disposed between the PVA resin film 111 of the polarizing plate and the liquid crystal layer 430.

According to the present embodiment, a method of manufacturing a display device including the "polarizing plate of the present invention which can be used even if the substrate film is used as a protective film and can be efficiently produced even if the thickness is thin" can be provided.

[Implementation 5: Display device]

Referring to Fig. 13, a display device 460 according to an embodiment 5 of the polarizing plate 160 of the present invention will be described. The display device 460 of the present embodiment is manufactured by using the polarizing plate of the present invention as one of a light source side polarizing plate and a viewing side polarizing plate, and stacking the polarizing plate to a liquid crystal panel.

Figure 13 is a cross-sectional view showing a display device 460 according to an embodiment 5 of the present invention. As shown in FIG. 13, the display device 460 has two substrates 410 & 420, a liquid crystal layer 430 interposed therebetween, and a polarizing plate 160 disposed on the outer surface (the lower surface in the drawing) of the lower substrate 410. The polarizing plate 160 is a polarizing plate of Modification 3. As shown in FIG. 13, the polarizing plate 160 is stacked such that the base film 112 of the polarizing plate is disposed between the PVA resin film 111 of the polarizing plate and the liquid crystal layer 430.

According to the present embodiment, a method of manufacturing a display device including the "polarizing plate of the present invention which can be used even if the substrate film is used as a protective film and can be efficiently produced even if the thickness is thin" can be provided.

[Implementation 6: Display device]

The polarizing plate manufactured using the stacked body for a polarizing plate of the present invention is used as a material of an EL display device.

In general, the organic EL display device includes a substrate, a transparent electrode, a light-emitting layer, and a metal electrode layer in this order from the light-emitting side. However, the polarizing plate obtained by the manufacturing method of the present invention can be disposed on the light-emitting side of the substrate.

The EL display device has two substrates, a light-emitting layer interposed therebetween, and a polarizing plate disposed on the outer side of one of the two substrates. The display device can be manufactured by stacking the polarizing plate of the present invention to an organic EL panel or an inorganic EL panel.

Next, a display device 500 according to an embodiment 6 of the "polarizing plate manufactured by using the stacked body for a polarizing plate of the present invention" will be described with reference to FIG. The display device 500 of the present embodiment is manufactured by stacking the polarizing plate 100 of the present invention to an organic EL panel.

Figure 14 is a cross-sectional view showing a display device 500 according to an embodiment 6 of the present invention. The display device 500 includes two substrates 510 & 520 , a light-emitting layer 530 interposed therebetween, and a polarizing plate 100 disposed on the outer surface (the lower surface in the drawing) of the lower substrate 510 . The polarizing plate 100 is a polarizing plate of the first embodiment. As shown in FIG. 14, the polarizing plate 100 is stacked such that the base film 112 of the polarizing plate 100 is disposed between the PVA resin film 111 of the polarizing plate 100 and the light-emitting layer 530.

According to the present embodiment, it is possible to provide a display device having the "polarizing plate of the present invention which can be used even if the substrate film is used as a protective film and can be efficiently produced even if the thickness is thin."

[Implementation type 7: display device]

Referring to Fig. 15, a display device 550 according to Embodiment 7 of the "polarizing plate manufactured using the stacked body of the present invention" will be described. The display device 550 of the present embodiment is manufactured by stacking the polarizing plate 120 of the present invention to an organic EL panel.

Figure 15 is a cross-sectional view showing a display device 550 according to an embodiment 7 of the present invention. The display device 550 has two substrates 510 & 520, a light-emitting layer 530 interposed therebetween, and a polarizing plate 120 disposed on the side of the lower substrate 510 (the side surface shown below). The polarizing plate 120 is a polarizing plate of Modification 1. As shown in FIG. 15, the polarizing plate 120 is stacked such that the base film 112 of the polarizing plate 120 is disposed between the PVA resin film 111 of the polarizing plate 120 and the light emitting layer 530.

According to the present embodiment, it is possible to provide a display device having the "polarizing plate of the present invention which can be used even if the substrate film is used as a protective film and can be efficiently produced even if the thickness is thin."

[Implementation 8: Display device]

Referring to Fig. 16, a description will be given of a display device 560 according to an embodiment 8 of the "polarizing plate manufactured using the stacked body of the present invention". The display device 560 of the present embodiment is manufactured by stacking the polarizing plate 160 of the present invention on an organic EL panel.

Figure 16 is a cross-sectional view showing a display device 560 according to an embodiment 8 of the present invention. The display device 560 has two substrates 510 & 520, a light-emitting layer 530 interposed therebetween, and a polarizing plate 160 disposed on the side of the lower substrate 510 (the side surface shown below). The polarizing plate 160 is a polarizing plate of Modification 3. As shown in FIG. 16, the polarizing plate 160 is stacked such that the base film 112 of the polarizing plate 160 is disposed between the PVA resin film 111 of the polarizing plate 160 and the light-emitting layer 530.

According to the present embodiment, it is possible to provide a display device having the "polarizing plate of the present invention which can be used even if the substrate film is used as a protective film and can be efficiently produced even if the thickness is thin."

[Other implementations]

(1) In the embodiment 3, it is disclosed that the polarizing plates of the embodiment 1 are used for the light source side polarizing plate and the viewing side polarizing plate, respectively, but any of the polarizing plates may be used to form any of the polarizing plates, and may be used. Two sheets of the polarizing plate of the embodiment 2 or the polarizing plates of the first to fourth embodiments were used.

(2) In the embodiment 4 and 5, the polarizing plate of the first modification and the polarizing plate of the third modification are used for one of the light source side polarizing plate and the viewing side polarizing plate, respectively, but the embodiment 1 may be used. The polarizing plate of Embodiment 2, Modification 2 or Modification 4.

(3) In the embodiments 6 to 8, the polarizing plate of the first embodiment, the polarizing plate of the first modification, and the polarizing plate of the third modification are respectively used in the organic EL display device, but the invention is not limited thereto. . For example, a polarizing plate of Embodiment 2, a polarizing plate of Modification 2, or a polarizing plate of Modification 4 can be used, and the polarizing plate of the present invention can also be used for an inorganic EL display device.

『Example』

The invention will be further described in detail below with reference to the examples and comparative examples, but the invention is not limited by the following examples. The "parts" and "%" of the ratios of the ingredients below indicate the parts by weight unless otherwise noted.

[Evaluation method]

[Weight average molecular weight (Mw) and molecular weight distribution (Mw/Mn)]

The molecular weight of the block copolymer and the block copolymer hydride was measured at 38 ° C as a standard polystyrene equivalent value of GPC which is a lysate of THF. A HLC8020GPC manufactured by TOSOH Corporation was used as a measuring device.

[Hydration rate]

The hydrogenation rate of the block copolymer hydride was calculated by ¹ H-NMR spectroscopy or GPC analysis. The region where the hydrogenation rate is 99% or less is calculated by measuring the ¹ H-NMR spectrum, and the region exceeding 99% is calculated from the ratio of the peak areas of the UV detector and the RI detector by GPC analysis.

[Measurement of MFR (melt flow rate measured at 190 ° C, load 2.16 kg)]

The melt flow rate was measured in accordance with JIS K7210 using an extruded plastometer (manufactured by Tateyama Scientific Co., Ltd., trade name "MELT INDEXER (L240)") as a measuring device at a temperature of 190 ° C and a load of 2.16 kg. Measurement.

[Measurement of tensile modulus of elasticity]

The tensile modulus of elasticity was measured in accordance with JIS K7127 using a tensile tester (manufactured by Instron Japan Company, Ltd., trade name "Motor-type universal material testing machine (5564)") by the following method.

The base film was punched into the shape of the test piece type 1B described in JIS K7127, and the stress when the test piece was stretched in the longitudinal direction and deformed was measured. The stress measurement conditions were set at a temperature of 23 ° C, a humidity of 60 ± 5% RH, a collet spacing of 115 mm, and a tensile speed of 50 mm/min. The stress measurement was performed 5 times. From the measured stress and the strain corresponding to the stress of the stress, the four-item measurement data with a 0.2% interval is selected in the range of the strain of the test piece of 0.6% to 1.2% (that is, the strain is 0.6). The measurement data at %, 0.8%, 1.0%, and 1.2%), and using the least squares method, the tensile elastic modulus was calculated from the four measurement data (total of 20 items) measured five times.

[Measurement method of phase difference]

The phase difference Re1 in the in-plane direction of the polyvinyl alcohol resin film, the phase difference Re2 in the in-plane direction of the extension of the base film, and the phase difference in the in-plane direction of the base film in the polarizing plate are phase difference meters. (manufactured by OPTO SCIENCE Co., Ltd., trade name "Mueller matrix polarimeter (Axo Scan)"). When measuring, the measurement wavelength was set at 550 nm.

As long as "the phase difference of the in-plane direction of the substrate film produced when the free end of the stack is uniaxially extended to 6.0 times at a temperature of 50 ° C" and "the free end of the stack at a temperature of 120 ° C" When the phase difference between the in-plane direction of the base film which is generated when the shaft is extended to 6.0 times is in the range of 0 nm or more and 20 nm or less, it is judged that "the stack is formed at a temperature of 50 ° C to 120 ° C. The phase difference Re2" in the in-plane direction of the base film produced when the free end is uniaxially extended to 6.0 times is 0 nm or more and 20 nm or less.

[Measurement method of thickness]

The thickness of each film (polyvinyl alcohol resin film and base film) included in the stack and the thickness of each film included in the polarizing plate are made by a thickness meter (manufactured by Mitutoyo Corporation, trade name "ABS digital thickness gauge ( 547-401)") was measured 5 times, and the average value was taken as the thickness of each film.

[Evaluation of adhesion]

In the process from the production of the polarizing plate of each of the examples to the second stretching treatment, the peeling of the polyvinyl alcohol resin film and the base film was defined as A, and the peeling was found to be B. And the person who is completely stripped is designated as C.

[Evaluation of drying processability]

In the drying process at 70 ° C for 5 minutes in the production of the polarizing plate of each example, the crack was not determined to be A in the case where the polarizer was not cracked, and the crack was determined as C.

[black offset]

The liquid crystal display panel is removed from the liquid crystal display device (trade name "IPS panel display (23MP47), manufactured by LG Electronics Japan, Inc.), and the polarizing plate disposed on the viewing side is peeled off, and the substrate film is placed on the panel side. The polarizing plates produced in the examples and the comparative examples were bonded. Further, a single unprotected film polarizer was attached to the polarizing plate produced in the examples and the comparative examples to recombine the liquid crystal display device. The absorption axes of the polarizing plates produced in the examples and the comparative examples and the polarizers of the single unprotected film were bonded in the same direction as the absorption axis of the polarizing plate before peeling.

When the direction of the absorption axis of the polarizing plate disposed on the viewing side is set to an azimuth angle of 0°, and the vertical direction of the panel is set to a polar angle of 0°, the panel is set to a black display state (that is, the entire panel is The display screen displays a black state), and from the azimuth angle of 45° and the polar angle of 45°, the color change of the polarizer without the protective film is determined to be the same as A, and the color change is judged as B, judge the change to be C.

[Example 1]

(1-1) Production of Polymer X

According to the production example described in Japanese Laid-Open Patent Publication No. 2002-105151, after 25 parts of the styrene monomer is polymerized in the first stage, 30 parts of the styrene monomer and 25 parts of the isoprene monomer are obtained in the second stage. After polymerization, 20 parts of the styrene monomer was polymerized in the third stage to obtain a block copolymer [D1], and then the block copolymer was hydrogenated to synthesize a block copolymer hydride [E1]. The block copolymer hydride [E1] had a Mw of 84,500, a Mw/Mn of 1.20, and a hydrogenation ratio of the main chain and the aromatic ring of almost 100%.

In the 100 parts of the block copolymer hydride [E1], melt-kneaded 肆{3-[3,5-di(tributyl)-4-hydroxyphenyl]propanoic acid} pentaerythritol ester (songyuan) 0.1 part of the product name "Songnox 1010" manufactured by Industrial Co., Ltd. was blended as an antioxidant, and then pelletized to obtain a polymer X for molding.

(1-2) Manufacture of base film

After dissolving the polymer X produced in (1-1) in cyclohexane, 40 parts by weight of polyisobutylene is added to 100 parts by weight of the polymer X (JD Nippon Mining & Energy Co., Ltd. The olefin HV-300", a number average molecular weight of 1,400), and 0.1 part by weight of an organic ruthenium compound (3-aminopropyltriethoxydecane, KBM903, manufactured by Shin-Etsu Chemical Co., Ltd.) was used to prepare a coating liquid for casting film formation.

The obtained coating liquid for film formation was applied to a separator ("MRV38" manufactured by Mitsubishi Chemical Corporation) using a die coater and dried. Thereby, a long substrate film comprising a polymer X having a width of 650 mm, a length of 500 m and a thickness of 10 μm was obtained. The base film had an MFR of 10 g/10 min and a tensile elastic modulus of 600 MPa.

(1-3) Fabrication of the stack

100 parts by weight of water, 3 parts by weight of a polyvinyl alcohol-based adhesive ("Z-200" manufactured by Nippon Synthetic Chemical Co., Ltd.), and 0.3 parts by weight of a crosslinking agent ("SPM-01" manufactured by Nippon Synthetic Chemical Co., Ltd.) were mixed to obtain a joint. Agent. This bonding agent was applied to one side of the base film produced in (1-2), and an unstretched polyvinyl alcohol resin film (average degree of polymerization of about 2400, degree of saponification of 99.9 mol%, width of 650 mm, A thickness of 20 μm, hereinafter also referred to as "PVA20"). In this state, the bonding agent was dried by heating at 70 ° C for 5 minutes to obtain a stacked body.

The thickness of the base film in the obtained stack, the thickness of the polyvinyl alcohol resin film, and the phase difference Re1 in the in-plane direction, and the phase difference Re2 were measured. The results are shown in Table 1. The temperature conditions for the uniaxial extension of the free end described above were set to 50 ° C and 120 ° C.

(1-4) Manufacture of polarizing plates

The stacked intermediate guide rolls manufactured in (1-3) were continuously conveyed in the longitudinal direction while performing the following operations.

The above-mentioned stacked body is subjected to a swell treatment of immersion in water, a dyeing treatment immersed in a dyeing solution containing iodine and potassium iodide, and a first stretching treatment of extending the dyed processed stack. Subsequently, the second extension treatment in which the stack after the first extension treatment is extended in a bath containing boric acid and potassium iodide is performed. The total stretch ratio indicated by the product of the stretch ratio at the time of the first stretching process and the stretch ratio at the time of the second stretching process was set to 6.0. The stacked body after the second elongation treatment was dried in a dryer at 70 ° C for 5 minutes (drying process) to obtain a polarizing plate.

The adhesion was evaluated in the process up to the second extension process, and the drying processability was evaluated in the drying process, and the obtained polarizing plate was evaluated for black shift. The evaluation results are disclosed in Table 1.

Further, the thickness and phase difference of the base film in the obtained polarizing plate and the thickness of the polyvinyl alcohol resin film were measured. The measurement results are disclosed in Table 1.

[Embodiment 2]

In addition to the use of 0.1 part by weight of an organic titanium compound (tetraisopropyl titanate, ORGATIX TA-8, manufactured by Matsumoto Fine Chemical Co., Ltd.) in the (1-2) of Example 1, 0.1 part by weight was replaced. A stack and a polarizing plate were prepared in the same manner as in Example 1 except for the base film obtained by the organic ruthenium compound, and evaluated in the same manner as in Example 1. The results are disclosed in Table 1.

[Example 3]

In addition to using 0.1 part by weight of an organic zirconium compound (n-propyl zirconate, ORGATIX ZA-45, manufactured by Matsumoto Fine Chemical Co., Ltd.) in the (1-2) of Example 1, 0.1 part by weight of organic was replaced. A stack and a polarizing plate were prepared in the same manner as in Example 1 except for the base film obtained by the ruthenium compound, and evaluated in the same manner as in Example 1. The results are disclosed in Table 1.

[Example 4]

In the case of performing the operation of applying the coating liquid for film formation to the separator and drying it by using a die coater, the coating amount and the like are adjusted to produce a long base having a thickness of 5 μm. A stack and a polarizing plate were produced in the same manner as in Example 1 except that the material film (the width and the length were the same as in Example 1), and evaluated in the same manner as in Example 1. The results are disclosed in Table 1.

[Example 5]

A stack and a polarizing plate were prepared in the same manner as in Example 1 except that polyisobutylene was not used in Example (1-2), and evaluation was carried out in accordance with Example 1. The results are disclosed in Table 2. The base film used in this Example 5 had an MFR of 3 g/10 min and a tensile elastic modulus of 800 MPa.

[Embodiment 6]

In the operation of (1-2) of the first embodiment, the organic ruthenium compound is not used, and when the coating liquid for coating film is applied to the separator and dried using a die coater, the coating amount or the like is adjusted to produce a thickness of A stack and a polarizing plate were prepared in the same manner as in Example 1 except that a base film of 5 μm long (the width and length were the same as in Example 1), and evaluated in the same manner as in Example 1. The results are disclosed in Table 2.

[Comparative Example 1]

In (1-4) of Example 1, only the unstretched polyvinyl alcohol resin film (PVA20) was used instead of the stack produced in (1-3), and the same operation as (1-4) was carried out. As a result, the first stretching treatment and the second stretching treatment were performed many times in the first stretching treatment and the second stretching treatment, and the fracture occurred many times in the drying step, and the adhesion and the black offset could not be evaluated.

[Comparative Example 2]

A cycloolefin-based resin film having a modulus of elasticity of 2,300 MPa (Zeonor Film, manufactured by Nippon Ryan, having a thickness of 13 μm, which cannot be measured at a temperature of 190 ° C and a load of 2.16 kg) was used in (1-3) of Example 1. A stack was produced in the same manner as in Example 1 except that the substrate film produced in (1-2) was replaced by MFR. As a result of performing the same operation as (1-4) of Example 1 using this stacked body, breakage occurred in the first stretching treatment, and a polarizing plate could not be produced.

The evaluation results of the examples and comparative examples are shown in Tables 1 and 2.

In the table, "COP" means a cycloolefin resin.

In the table, "Re2 (50 ° C)" means a phase difference in the in-plane direction of the base film which is produced when the free end of the stack is uniaxially stretched to 6.0 times at a temperature of 50 ° C. Re2 (120 ° C)" means a phase difference in the in-plane direction of the substrate film produced when the free end of the stack is uniaxially stretched to 6.0 times at a temperature of 120 °C.

In the table, "Re1" means a phase difference in the in-plane direction of the polyvinyl alcohol resin film in the stack.

"Table 1"

"Table 2"

As is apparent from the results of Tables 1 and 2, according to the present invention, it is possible to reduce the phase difference appearing in the base film after the step of extending the stacked body, and to obtain polarized light excellent in adhesion, drying processability, and optical physical properties. board. In this way, it is possible to provide a stack for a polarizing plate which can be used even if the base film is used as a protective film, and which can be efficiently produced even if the thickness is thin, a polarizing plate and a display device using the same, and a polarizing plate. Manufacturing method.

10, 15‧‧‧Stacks (stacks for polarizers)

11‧‧‧Plastic Alcohol Resin Film (PVA Resin Film)

12‧‧‧Substrate film

13‧‧‧Adhesive layer

100, 120, 130, 150, 160, 170‧ ‧ polarizing plates

111‧‧‧Plastic Alcohol Resin Film (PVA Resin Film)

112‧‧‧Substrate film

113, 114‧‧‧ adhesive layer

115‧‧‧Protective film

116‧‧‧Binder layer

200‧‧‧ manufacturing equipment

201, 202‧‧‧ rolled out device

203‧‧‧ Winding device

205‧‧‧Fitting device

300‧‧‧ manufacturing equipment

301, 307‧‧‧ rolled out device

302～305‧‧‧Processing device

306, 309‧‧‧Drying device

308‧‧‧Fitting device

310‧‧‧Winding device

400, 450, 460‧‧‧ display devices (liquid crystal display devices)

410, 420‧‧‧ substrate

430‧‧‧Liquid layer

500, 550, 560‧‧‧ display devices (organic EL display devices)

510, 520‧‧‧ substrate

530‧‧‧Lighting layer

Fig. 1 is a schematic cross-sectional view showing a stack for a polarizing plate according to Embodiment 1 of the present invention.

Fig. 2 is a schematic view showing an example of a manufacturing apparatus of a stack for a polarizing plate according to Embodiment 1.

Fig. 3 is a schematic cross-sectional view showing a polarizing plate manufactured by using the stacked body for a polarizing plate according to Embodiment 1 of the present invention.

FIG. 4 is a schematic view showing an example of a manufacturing apparatus for manufacturing a polarizing plate using the stacked body for a polarizing plate according to the first embodiment.

Fig. 5 is a schematic cross-sectional view showing a polarizing plate according to a first modification of the polarizing plate stack according to the first embodiment of the present invention.

Fig. 6 is a cross-sectional view showing a polarizing plate according to a second modification of the polarizing plate stack according to the first embodiment of the present invention.

Fig. 7 is a schematic cross-sectional view showing a stack for a polarizing plate according to Embodiment 2 of the present invention.

Fig. 8 is a schematic cross-sectional view showing a polarizing plate manufactured by using the stacked body for a polarizing plate according to Embodiment 2 of the present invention.

Fig. 9 is a schematic cross-sectional view showing a polarizing plate of a third modification produced by using the stacked body for a polarizing plate according to Embodiment 2 of the present invention.

Fig. 10 is a schematic cross-sectional view showing a polarizing plate of a fourth modification produced by using the stacked body for a polarizing plate according to Embodiment 2 of the present invention.

Fig. 11 is a cross-sectional view showing a display device according to an embodiment 3 of the present invention.

Fig. 12 is a cross-sectional view showing a display device according to an embodiment 4 of the present invention.

Fig. 13 is a cross-sectional view showing a display device according to an embodiment 5 of the present invention.

Fig. 14 is a cross-sectional view showing a display device according to an embodiment 6 of the present invention.

Fig. 15 is a cross-sectional view showing a display device according to an embodiment 7 of the present invention.

Fig. 16 is a cross-sectional view showing a display device according to an embodiment 8 of the present invention.

Claims (15)

A stack for a polarizing plate comprising a stack of polarizing plates of an unstretched polyvinyl alcohol resin film and a base film, wherein a phase difference Re1 of the in-plane direction of the polyvinyl alcohol resin film is 50 nm or less, and The thickness T is 45 μm or less, and the base film is a film made of a resin having a melt flow rate of 1 g/10 minutes or more, and the melt flow rate is measured at 190 ° C and a load of 2.16 kg. The value of the tensile modulus E of the resin is 50 MPa or more and 1200 MPa or less, and the phase difference Re2 in the in-plane direction of the extension of the base film is 0 nm or more and 20 nm or less, and the phase difference Re2 is based on The polarizing plate is uniaxially stretched to 6.0 times with respect to the free end of the stack at a temperature of 50 ° C to 120 ° C, and the extension film has a phase difference when the base film is formed into the extension. The stack for polarizing plates according to claim 1, wherein the resin is a cyclic olefin-based resin containing a cycloolefin-based polymer, and the cycloolefin-based polymer hydrogenates the block copolymer [D] a hydride of a block copolymer [D] consisting of a polymer block [A] having a repeating unit [I] derived from an aromatic vinyl compound as a main component a repeating unit [I] of an aromatic vinyl compound and a polymer block [B] derived from a repeating unit [II] of a chain conjugated diene compound as a main component, or a chain conjugated diene compound The repeating unit [II] is formed as a main component of the polymer block [C]. A stack for a polarizing plate comprising a stack of polarizing plates of an unstretched polyvinyl alcohol resin film and a base film, wherein a phase difference Re1 of the in-plane direction of the polyvinyl alcohol resin film is 50 nm or less, and The thickness T is 45 μm or less, and the base film is a film made of a resin, and the resin is a cycloolefin resin containing a cycloolefin polymer, and the cycloolefin polymer is a block copolymer. a hydrogenated block copolymer [D] consisting of a polymer block having a repeating unit [I] derived from an aromatic vinyl compound as a main component [A] And a polymer block [B] having a repeating unit [I] derived from an aromatic vinyl compound and a repeating unit [II] derived from a chain conjugated diene compound as a main component, or a chain derived from a chain The repeating unit [II] of the conjugated diene compound is a polymer block [C] as a main component, and the phase difference Re2 in the in-plane direction of the extension of the base film is 0 nm or more and 20 nm or less. The difference Re2 is based on the temperature of 50 ° C ~ 120 ° C The light plate is uniaxially extended to 6.0 times with the free end of the stack, and the extension has a phase difference when the substrate film is formed into the extension. The stack for a polarizing plate according to claim 2, wherein the cycloolefin resin contains a plasticizer, a softener or both. The stack for a polarizing plate according to claim 4, wherein the plasticizer, the softener or both are selected from one or more of an ester plasticizer and an aliphatic hydrocarbon polymer. The stack for a polarizing plate according to claim 1 or 3, wherein the resin contains an organometallic compound. The stack for a polarizing plate according to claim 1 or 3, wherein the base film is interposed with the adhesive layer and stacked on the polyvinyl alcohol resin film. A polarizing plate which is uniaxially stretched with a stack according to any one of claims 1 to 7. The polarizing plate according to claim 8, wherein a protective film or a binder is provided on a surface of the polarizing plate on which the polyvinyl alcohol resin film is not stacked. The polarizing plate according to claim 9, wherein the protective film is made of one or more resins selected from the group consisting of a cycloolefin resin, an acrylic resin, a polyethylene terephthalate resin, and a triacetyl cellulose resin. A display device having two substrates, a liquid crystal layer interposed therebetween, and a polarizing plate according to any one of claims 8 to 10, wherein the polarizing plate is disposed on an outer side of at least one of the two substrates . A display device having two substrates, a light-emitting layer interposed therebetween, and a polarizing plate according to any one of claims 8 to 10, wherein the polarizing plate is disposed outside one of the two substrates. The display device according to claim 11, wherein a substrate film of the polarizing plate is disposed between the polyvinyl alcohol resin film of the polarizing plate and the liquid crystal layer. The display device according to claim 12, wherein a substrate film of the polarizing plate is disposed between the polyvinyl alcohol resin film of the polarizing plate and the light emitting layer. A method of producing a polarizing plate, comprising the step of uniaxially extending a stack for a polarizing plate according to any one of claims 1 to 7.