JP2003227928A - Polarizing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarizing plate which has a protective sheet of a polarizer exhibiting excellent mechanical and environmental characteristics without making the characteristics of the PVA (polyvinyl alcohol) polarizer degenerate for a long period of time. <P>SOLUTION: The polarizing plate comprises a polarizer P having protective sheets A each of which is composed of a base layer B and a hot melt adhesive layer C laminated on both surfaces thereof. The base layers B and the polarizer P are stuck together via the hot melt adhesive layers C so as to form the laminated sheet. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polarizing plate. More specifically, a polarizer cover sheet having strong adhesion to a polarizer P made of uniaxially oriented polyvinyl alcohol impregnated with iodine and having excellent transparency, optical isotropy, moisture resistance, heat resistance and the like. The present invention relates to a polarizing plate in which is laminated.

[0002]

2. Description of the Related Art A polarizing film is used for liquid crystal displays and the like, and the polarizing film is composed of three layers in which protective layers are laminated on both sides of a polarizer.

As the polarizer, a uniaxially oriented film in which iodine or dye is adsorbed and dispersed in polyvinyl alcohol (PVA) is usually used.

Since this PVA polarizer shrinks due to heat and moisture and deteriorates the polarization function, it is a laminate having protective layers adhered on both sides thereof. The protective layer has no birefringence and is optically isotropic, has high light transmittance, has excellent moisture resistance and heat resistance, has excellent mechanical properties, and has good flatness. It is required that the adhesiveness with the polarizer is good. Therefore, a triacetyl cellulose (TAC) film has been conventionally used.

However, the TAC film has insufficient moisture resistance, so that not only the polarizing function is rapidly deteriorated under high temperature and high humidity, but also the adhesiveness with the polarizer is poor and there is a problem of peeling. . In addition to the problem that TAC film has weak mechanical strength and it is difficult to thin the film, the use of a solvent called methylene chloride is indispensable in the TAC film manufacturing process, and the influence on the environment may be a problem. is there.

[0006]

[Patent Document 1] Japanese Patent Laid-Open No. 4-3
39821, JP-A-5-212828, JP-A-10-101907, and JP-A-10-1304.
As disclosed in Japanese Unexamined Patent Publication No. 02, etc., it is shown that a thermoplastic norbornene-based resin having good moisture resistance is used instead of the TAC film sheet. However, the thermoplastic norbornene-based resin has a drawback that it cannot obtain strong adhesion with the PVA-based polarizer.

[0007]

The present invention provides a polarizing plate in which the above-mentioned drawbacks are improved, and has the following constitution.

That is, the polarizing plate of the present invention is a polarizing plate in which a protective sheet A composed of a base layer B and a hot-melt adhesive layer C is laminated on both surfaces of a polarizer P, and the base layer B and the polarizer are A polarizing plate, wherein P is a laminated sheet adhered by the hot melt adhesive layer C.

More specifically, more preferably, a polymer resin sheet A comprising a transparent base layer B having a hot-melt adhesive layer C having a thickness of 0.5 to 10 μm on both sides of a polarizer P,
In a polarizing plate formed by hot-melt adhesion to the polarizer P, the hot-melt adhesion layer C is made of ethylene / vinyl acetate copolymer resin (EVA), EVA is partially saponified, and the vinyl acetate component of EVA is 10% by weight or more 40
The polarizing plate is characterized by having a range of not more than wt% and a saponification degree of EVA of 5% to 90%.

Further, in the polarizing plate according to the present invention, the retardation of the polymer sheet A is preferably 10 nm or less, more preferably 5 nm or less, and the water vapor permeability is preferably 50 g / m ² · day · 0.1 mm. Less than,
It is more preferably 10 g / m ² · day · 0.1 mm or less, and the light transmittance is preferably 88% or more, more preferably 90% or more.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below.

The polarizing plate of the present invention is a polarizing plate in which a protective sheet A is laminated on both sides of a polarizer P, the protective sheet comprising a base layer B and a hot melt adhesive layer C, and the hot melt adhesive layer C. The base layer B and the polarizer P are adhered to each other to form a laminated sheet structure.

In the present invention, for example, a protective sheet made of a thermoplastic norbornene-based resin or the like having excellent water resistance as a PVA-based polarizer protective sheet is adhered to the polarizer P by a hot-melt adhesive. It is possible to provide a polarizing plate which has excellent adhesiveness and is durable and does not have a swelling phenomenon at the adhesive interface with the passage of time.

The polymer compound constituting the base layer B is a cyclic olefin copolymer, hydrogenated polystyrene, poly-4-methylpentene-1, polycarbonate, polyarylate, polysulfone, polyether sulfone, acrylic polymer. , And an amorphous thermoplastic polymer or thermosetting epoxy resin selected from the modified products thereof can be used. In the case of the present invention, a ring having a particularly low water vapor transmission rate, being transparent and having a high glass transition temperature can be used. Olefin copolymers are preferred.

More specifically, the cyclic olefin copolymer (COC) has a norbornene skeleton and has a temperature of 120 ° C.
By hydrogenating a high Tg polyolefin having the above glass transition temperature (Tg), a tetracyclododecene derivative, or a polymer obtained by metathesis polymerization with an unsaturated cyclic compound copolymerizable with the tetracyclododecene. There are polymers obtained, and they are disclosed in JP-A-60-168708, JP-A-62-252406 and JP-A-62-2.
No. 52407, JP-A-63-145324,
JP-A-63-264626, JP-A-1-2405
17, JP-A-2-133413, JP-B-5
7-8815, etc.

For example, the side chain of COC has (CH ₂ ) nCO
Those having a polar group such as OR as appropriate, for example, those having one polar group in every 2 to 5 norbornene groups are also preferable, but many polar groups having all polar groups in all norbornene groups are preferable. In the case of containing a group, the water vapor transmission rate exceeds 50 g / m ² · day · 0.1 mm sheet, and further the water absorption rate and the humidity expansion coefficient β increase, and the characteristics as a protective function are impaired, which is not preferable.

The thickness of the base layer B affects the thickness of the polarizing plate as a whole and is preferably as thin as possible. However, in order to prevent the deformation of the polarizer, it is preferably in the range of 20 to 150 μm.
Most preferably, it is 40 to 80 μm.

Of course, various additives such as a slip agent, a stabilizer, an antioxidant, an ultraviolet absorber and an antistatic agent may be added to the base layer B.

Before laminating the hot melt adhesive on the base layer B, the layer B is subjected to surface activation treatment in order to increase mutual adhesive force, and then the hot melt adhesive is laminated by coating. Is good. Examples of the surface activation treatment include plasma treatment, corona discharge treatment, chemical treatment, roughening treatment, etching treatment and flame treatment, which may be used alone or in combination.

In the case of the present invention, plasma treatment, corona discharge treatment, and flame treatment, which are dry treatments, are particularly preferable.
Further, atmospheric pressure plasma treatment and corona discharge treatment in the presence of polar gas such as carbon dioxide are particularly preferable from the viewpoints of economical efficiency and adhesiveness.

At this time, the hot melt adhesive layer C is coated and laminated on the surface of the base layer B which has been surface-treated so that the surface tension of the base layer B is 40 mN / m or more, preferably 50 mN / m or more.

Here, the hot-melt adhesive layer C means an adhesive layer in which a thermoplastic resin, a tacky adhesive resin, or a thermosetting resin that is fused by laminating with a heating roll is laminated. Examples of the plastic resin include acrylic resins, polyester resins such as polyester / polycarbonate, olefin resins such as ethylene / propylene, amide resins such as nylon, and vinyl resins such as vinyl chloride / vinyl acetate / polyvinyl alcohol. Examples of the adhesive resin include acrylic resin such as acrylic acid ester, synthetic rubber resin such as butadiene rubber, and urethane resin as the thermosetting resin.
Examples thereof include melamine resin, phenol resin, urea resin and epoxy resin.

In order to be able to adhere to both the polyvinyl alcohol constituting the polarizer P and the base layer B, resins having various polar groups are preferable. In the present invention,
A resin having a —OH group, a —COOH group, or the like is preferable, and a partially saponified ethylene-vinyl acetate copolymer resin (EVA) is particularly preferable.

In order to further strengthen the adhesiveness with the polarizer P, it is preferable to further provide a laminated film of modified polyvinyl alcohol on the surface of the hot melt adhesive layer C.

The laminated film of modified polyvinyl alcohol is
Examples include low molecular weight polyvinyl alcohol or polyvinyl alcohol to which a polar group such as an amino group, a nitrile group or an isocyanate group is added, polyvinyl butyral, polyvinyl pyrrolidone, polyvinyl formal, poly N-vinyl acetamide and the like. The thickness is preferably 1 μm or less.

It is an important and preferable point that the ethylene / vinyl acetate copolymer resin (EVA) of the hot melt adhesive layer C laminated on the base layer B is partially saponified.
The vinyl acetate component in EVA is in the range of 5% by weight to 90% by weight, and more preferably in the range of 10% by weight to 40% by weight. When the amount of vinyl acetate component is small, the melting point at the time of hot melt becomes high, which may deteriorate the performance of the PVA-based polarizer P and may cause poor appearance, which is not preferable. On the other hand, if the amount is too large, the cohesive force of the coating film may decrease, and sufficient adhesiveness may not be obtained.

The saponification degree of EVA is preferably in the range of 3% to 98%, more preferably in the range of 5% to 90%. If the saponification degree is low, the adhesion to PVA cannot be sufficiently obtained, which is not preferable. Further, the completely saponified product has high crystallinity and poor adhesion to the base layer B, which is not preferable.

The EVA of the hot melt adhesive layer C preferably contains a curing agent, and the curing agent to be added is preferably an isocyanate type curing agent. As the isocyanate-based curing agent, relatively common ones such as hexamethylene diisocyanate (HDI), toluene diisocyanate (TDI), diphenylmethane-4,4 ′ diisocyanate (MDI), metaxylylene diisocyanate (MXDI), or the like, or These derivatives are preferred.

The amount of the isocyanate-based curing agent added varies depending on the type of isocyanate and the amount of addition of the terminal reactive group.
0.1 to 5% by weight is preferable with respect to VA.

The thickness of the hot-melt adhesive layer C is 0. 0 in order to maintain sufficient adhesiveness between the base layer B and the polarizer P.
It is preferably 5 to 10 μm. Further, a thickness of 3 to 6 μm is more preferable in terms of compatibility of adhesiveness, transparency and photoelasticity.

As a method for laminating the hot melt adhesive layer C on the base layer B, a method of melt coextruding the hot melt adhesive with a base layer polymer, or a method of hot melt adhesive as a solvent solution or an aqueous dispersion on the base layer B is used. Examples of the method include a method of laminating by coating and a method of coating and laminating the hot-melt adhesive on the base layer B in a state of being heated and melted. In order to obtain a uniform thickness and a good appearance, the hot-melt adhesive is mixed with a solvent. A method of coating the base layer B as a solution or an aqueous dispersion by coating is preferable. As the coating method, gravure roll coating, reverse roll coating, slit die coating, bar coater coating and the like are preferable.

To the hot melt adhesive layer C, an ultraviolet absorber, an antistatic agent, a lubricant and the like may be added if necessary.

The hot melt adhesive layer C is laminated on the base layer B, and the obtained polymer resin sheet A, polyvinyl alcohol, and iodine are uniaxially oriented thicknesses 2 as main constituents.
The stacking method with the polarizer P of about 5 μ is A (B / C)
A method of laminating a sheet having a structure of / P / A (C / B) with a heating roll is preferable. The temperature of the heating roll at this time is preferably 60 to 120 ° C, more preferably 80 to 100 ° C. If the roll temperature is too high, the polarizer P is thermally deformed and the appearance is deteriorated.
This may cause a decrease in the degree of polarization. On the other hand, if the roll temperature is too low, the hot melt adhesive layer C does not melt, so that sufficient laminating adhesive strength cannot be obtained.

The polarizing plate thus obtained is thinner than conventional polarizing plates using triacetyl cellulose (TAC) as a protective film, has excellent adhesiveness, and has water resistance and moisture resistance. It has excellent characteristics such as excellent in environmental impact and low environmental load. [Measurement Method of Physical Properties] The measurement method of the physical property values used in the present invention will be described below. 1. Film thickness unevenness: Measured using a film thickness tester KG601A manufactured by Anritsu Corporation. 2. Thermal properties (Tg, Tm): Perkin Elmer D
Using a SC-II type measuring device, the sample weight was 10 mg, and the temperature was raised under a nitrogen stream at a temperature rising rate of 20 ° C./min, and the temperature at which the start of baseline deviation started was further raised to the glass transition point Tg. The exothermic peak was taken as Tcc, and the endothermic peak temperature associated with crystal melting was taken as the melting point Tm. Tm + 20 ° C
After the temperature was maintained for 1 minute, the melt was cooled at a cooling rate of 20 ° C./minute, and the exothermic peak temperature due to crystallization was taken as Tmc. 3. Water vapor transmission rate: PERMATRAN manufactured by MOCON
Using -W3 / 30, the measurement was performed according to JIS K7129B method (infrared sensor method) under the condition of 25 ° C / 90% RH. 4. Light transmittance: The total light transmittance of visible light in the wavelength range of 300 to 700 nm was measured using a spectrophotometer U3410 manufactured by Hitachi Ltd. 5. Haze: Direct reading haze computer (HGM-2D
P: Haze was measured using Suga Test Instruments Co., Ltd. 6. Retardation: Measured using an automatic birefringence meter KOBRA-21ADH manufactured by Shin Oji Paper Co., Ltd.

[0035]

The present invention will be described in more detail based on the following examples. Example 1 In a polarizing plate formed by laminating a polymer resin sheet A, the base layer B of the sheet A is a norbornene-based resin cyclic olefin copolymer COC (Zeonor 1600 manufactured by Nippon Zeon Co., Ltd.) and vacuum dried. After degassing the water content and the dissolved oxygen by means of the above, the material from the raw material hopper to the extruder was supplied to a 65 mm extruder in which nitrogen was replaced, and melted at 280 ° C.

On the other hand, a polyethylene terephthalate (PET) resin was vacuum-dried as a resin D to be laminated so as to surround the resin B and then supplied to a 40 mm melt extruder and melted at 285 ° C. After passing through the filter for cutting the above-mentioned foreign matters, D / B / D was formed into three layers in the thickness direction, and the mixture was extruded from a crow-mouth-shaped T-die die onto a casting drum. In order to improve the adhesion between the casting drum and the extruded molten resin sheet, just before the grounding point, from the non-drum surface side, using a 0.15 mm diameter wire of tungsten, 10 kV, 5 m
Applying the positive charge of A, the molten resin sheet was brought into close contact with and cooled and solidified on a specular chrome-plated drum kept at 40 ° C.

The thus-obtained three-layer cast film had a total thickness of 60 μm, with each layer having a thickness of 10/40/10 μm. Excellent, retardation 1.0nm, visible light transmittance (wavelength 400-700n
m) was a sheet having a transparency of 90% or more and excellent in optical isotropy.

A corona discharge treatment was applied to one surface of the film to coat the hot melt adhesive layer C. The hot-melt adhesive layer C is made of ethylene / vinyl acetate copolymer resin, Dumilan D-251S (vinyl acetate component 28%,
Takenate D-170N was added to a 10 wt% toluene solution having a saponification degree of 10% as an isocyanate curing agent.
What added 5 parts was used. It was applied with a bar coater so that the thickness after drying was 5 μm, and dried at 120 ° C.

On the other hand, a polymer resin in which a hot melt adhesive layer C is laminated on the COC resin film base layer B having a thickness of 40 μm by 5 μm on both surfaces of a uniaxially oriented polarizer P having a thickness of 20 μm made of polyvinyl alcohol and iodine. Sheet A is hot laminated with a 100 ° C heating roll, and B / C
A polarizing plate having a thickness of 110 μm and composed of 5 layers of / P / C / B was obtained.

Since this polarizing plate is firmly adhered, and the base layer B is a hydrophobic sheet and has a very low water vapor transmission rate, there is no change in the characteristics and appearance of the polarizer even when left for a long time under high humidity. I can't. Example 2 As a cyclic olefin copolymer COC which is a norbornene-based resin for the base layer B, Arton FX26 manufactured by JSR Corporation,
A polarizing plate was prepared in the same manner as in Example 1 except that 50 μm was used. This is Example 2.

This polarizing plate is firmly adhered, and since the base layer B is a hydrophobic sheet and has a very low water vapor transmission rate, there is no change in the characteristics or appearance of the polarizer even when it is left under high humidity for a long time. can not see. Example 3 As a cyclic olefin copolymer COC which is a norbornene-based resin for the base layer B, APL60 manufactured by Mitsui Chemicals, Inc.
A polarizing plate was prepared in the same manner as in Example 1 except that 15T and 50 μm were used. This is Example 3.

This polarizing plate is firmly adhered, and since the base layer B is a hydrophobic sheet and has a very low water vapor transmission rate, there is no change in the characteristics or appearance of the polarizer even when it is left under high humidity for a long time. can not see. Example 4 As an olefin copolymer for the base layer B, poly-4-methylpentene-1 (Opulan X manufactured by Mitsui Chemicals, Inc.) was used.
A polarizing plate was made in the same manner as in Example 1 except that (22, 50 μm) was used. This is Example 4.

This polarizing plate is firmly adhered, and since the base layer B is a hydrophobic sheet and has a very low water vapor transmission rate, there is no change in the characteristics or appearance of the polarizer even when left for a long time under high humidity. can not see. Example 5 Corona discharge treatment was performed on one surface of the base layer B of Example 1,
The hot melt adhesive layer C was coated. The hot melt adhesive layer C is an ethylene / vinyl acetate copolymer resin,
Mitsui Takeda Chemicals Co., Ltd. Dumilan D-251S (vinyl acetate component 28%, saponification degree 10%) 10 wt% toluene solution was added with 1.5 parts of Takenate D-170N as an isocyanate curing agent. As a thermoplastic polyamide resin based on parts by weight and dimer acid, 10w of Macromelt 6801 manufactured by Henkel Japan Ltd.
25 parts by weight of a t% toluene / IPA solution was used. Apply with a bar coater so that the thickness after drying is 5 μm, and
It was dried at 20 ° C.

On the other hand, a polymer resin in which a hot-melt adhesive layer C is laminated on the COC resin film base layer B of 40 μm in thickness of 5 μm on both surfaces of a uniaxially oriented polarizer P of polyvinyl alcohol and iodine having a thickness of 20 μm. Sheet A is hot laminated with a heating roll at 100 ° C.
A polarizing plate having a thickness of 110 μm and composed of 5 layers of / C / P / C / B was obtained.

This polarizing plate is firmly adhered, and since the base layer B is a hydrophobic sheet and has a very low water vapor transmission rate, there is no change in the characteristics or appearance of the polarizer even when it is left under high humidity for a long time. can not see. Example 6 One side of the base layer B of Example 1 was subjected to corona discharge treatment,
The hot melt adhesive layer C was coated. The hot melt adhesive layer C is an ethylene / vinyl acetate copolymer resin,
Takenate D-170N as an isocyanate curing agent in a 10 wt% toluene-ethyl acetate solution of NUC-3185 (vinyl acetate component 28%) manufactured by Nippon Unicar Co., Ltd.
As a polyvinylpyrrolidone resin, 75 parts by weight of 1.5 parts was added and 25 parts by weight of a 10 wt% toluene / IPA solution of PX-P90K manufactured by Nippon Shokubai Co., Ltd. was used.
It was applied with a bar coater so that the thickness after drying was 5 μm, and dried at 120 ° C.

On the other hand, a polymer resin sheet A in which a hot melt adhesive layer C is laminated on the above 40 μm COC resin film base layer B by 5 μm on both surfaces of a uniaxially oriented polarizer P of polyvinyl alcohol and iodine having a thickness of 20 μm.
Is hot-laminated with a 100 ° C heating roll, and B / C
A polarizing plate having a thickness of 110 μm and composed of 5 layers of / P / C / B was obtained.

This polarizing plate is firmly adhered, and since the base layer B is a hydrophobic sheet and has a very low water vapor transmission rate, there is no change in the characteristics or appearance of the polarizer even when it is left under high humidity for a long time. can not see. Example 7 Corona discharge treatment was performed on one surface of the base layer B of Example 1,
The hot melt adhesive layer C was coated. The hot melt adhesive layer C is an ethylene / vinyl acetate copolymer resin,
Mitsui Takeda Chemicals Co., Ltd. Dumilan D-251S (vinyl acetate component 28%, saponification degree 10%) 10 wt% toluene solution was added with 1.5 parts of Takenate D-170N as an isocyanate curing agent. As the parts by weight and polyvinyl butyral resin (PVB), 25 parts by weight of a 10 wt% toluene solution of S-REC BL-S manufactured by Sekisui Chemical Co., Ltd. was used. It was applied with a bar coater so that the thickness after drying was 5 μm, and dried at 120 ° C.

On the other hand, a polymer resin sheet A in which a hot-melt adhesive layer C is laminated on the above-mentioned 40 μm COC resin film base layer B by 5 μm on both surfaces of a uniaxially oriented polarizer P of polyvinyl alcohol and iodine having a thickness of 20 μm.
Is hot-laminated with a 100 ° C heating roll, and B / C
A polarizing plate having a thickness of 110 μm and composed of 5 layers of / P / C / B was obtained.

This polarizing plate is firmly adhered, and since the base layer B is a hydrophobic sheet and has a very low water vapor transmission rate, there is no change in the characteristics or appearance of the polarizer even when it is left under high humidity for a long time. can not see. Example 8 One side of the base layer B of Example 1 was subjected to corona discharge treatment,
The hot melt adhesive layer C was coated. The hot melt adhesive layer C is an ethylene / vinyl acetate copolymer resin,
Mitsui Takeda Chemical Co., Ltd. Dumilan D-251S (vinyl acetate component 28%, saponification degree 10%) in 10 wt% toluene solution, used as an isocyanate-based curing agent, 1.5 parts of Takenate D-170N is used. I was there. Apply with a bar coater so that the thickness after drying will be 5 μm,
It was dried at 120 ° C.

Furthermore, low molecular weight polyvinyl alcohol (Nippon Gosei Kagaku KK Denka Poval AL-
06) A 5% aqueous solution was applied by a bar coater so that the thickness after drying was 0.5 μm, and dried at 120 ° C. This layer is referred to as D layer.

On the other hand, the polymer resin sheet A was uniaxially oriented with polyvinyl alcohol and iodine and had a thickness of 20 μm.
Hot laminating with a heating roll at ℃, B / C / D / P /
A polarizing plate having a thickness of 110 μm and composed of 5 layers of D / C / B was obtained.

This polarizing plate is firmly adhered, and since the base layer B is a hydrophobic sheet and has a very low water vapor transmission rate, there is no change in the characteristics or appearance of the polarizer even when left for a long time under high humidity. can not see. Comparative Example 1 A cellulose triacetate (TAC) film (Fujitac 80 μm manufactured by Fuji Film Co., Ltd.) is laminated on both surfaces of a uniaxially oriented polarizer P having a thickness of 20 μm made of polyvinyl alcohol and iodine, using an aqueous polyvinyl alcohol solution as an adhesive. did. This was designated as Comparative Example 1.

When this polarizing plate was left to stand in a high humidity atmosphere of 40 ° C. and 90% RH, the degree of polarization was reduced more rapidly than in Examples 1-8.

[0054]

[Table 1]

[0055]

Industrial Applicability According to the present invention, there is provided a polarizing plate which is excellent in moisture resistance and is very useful as a display screen of a liquid crystal display screen, especially in a mobile phone or an automobile navigator whose environment changes greatly.

Continued front page    F-term (reference) 2H049 BA02 BB27 BB28 BB29 BB34                       BB43 BB51 BB62 BC22                 2H091 FA08X FA08Z FB02 GA16                       GA17 LA02 LA12 LA30

Claims (7)

[Claims] 1. A polarizing plate in which a protective sheet A comprising a base layer B and a hot melt adhesive layer C is laminated on both sides of a polarizer P, wherein the base layer B and the polarizer P are the hot melt adhesive layer. A polarizing plate comprising a laminated sheet adhered by C. 2. The base layer B is made of a polymer compound,
The polymer compound is an amorphous thermoplastic selected from a cyclic olefin copolymer, hydrogenated polystyrene, poly-4-methylpentene-1, polycarbonate, polyarylate, polysulfone, polyethersulfone, and modified products thereof. The polarizing plate according to claim 1, which is a polymer. 3. The polarized light according to claim 1, wherein the hot melt adhesive layer C is made of an ethylene / vinyl acetate copolymer resin, and the ethylene / vinyl acetate copolymer resin is partially saponified. Board. 4. The polarizing plate according to claim 3, wherein the vinyl acetate component of the ethylene / vinyl acetate copolymer resin is in the range of 10% by weight or more and 40% by weight or less. 5. The polarizing plate according to claim 3, wherein the ethylene / vinyl acetate copolymer resin has a saponification degree of 5% to 90%. 6. The ethylene / vinyl acetate copolymer resin comprises a curing agent.
The polarizing plate according to any one of to 5. 7. The thickness of the hot melt adhesive layer C is 0.5 to.
It is 10 micrometers, The polarizing plate in any one of Claims 1-6 characterized by the above-mentioned.