WO2024116890A1 - Polarizing plate and display device using same - Google Patents

Polarizing plate and display device using same Download PDF

Info

Publication number
WO2024116890A1
WO2024116890A1 PCT/JP2023/041394 JP2023041394W WO2024116890A1 WO 2024116890 A1 WO2024116890 A1 WO 2024116890A1 JP 2023041394 W JP2023041394 W JP 2023041394W WO 2024116890 A1 WO2024116890 A1 WO 2024116890A1
Authority
WO
WIPO (PCT)
Prior art keywords
meth
acrylate
protective film
polarizing plate
film
Prior art date
Application number
PCT/JP2023/041394
Other languages
French (fr)
Japanese (ja)
Inventor
亜也加 ▲高▼野
伸 川田
和真 荒堀
Original Assignee
株式会社トッパンＴｏｍｏｅｇａｗａオプティカルフィルム
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社トッパンＴｏｍｏｅｇａｗａオプティカルフィルム filed Critical 株式会社トッパンＴｏｍｏｅｇａｗａオプティカルフィルム
Publication of WO2024116890A1 publication Critical patent/WO2024116890A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B23/00—Layered products comprising a layer of cellulosic plastic substances, i.e. substances obtained by chemical modification of cellulose, e.g. cellulose ethers, cellulose esters, viscose
    • B32B23/04—Layered products comprising a layer of cellulosic plastic substances, i.e. substances obtained by chemical modification of cellulose, e.g. cellulose ethers, cellulose esters, viscose comprising such cellulosic plastic substance as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B23/08—Layered products comprising a layer of cellulosic plastic substances, i.e. substances obtained by chemical modification of cellulose, e.g. cellulose ethers, cellulose esters, viscose comprising such cellulosic plastic substance as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/02—Physical, chemical or physicochemical properties
    • B32B7/023—Optical properties
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
    • G02B1/10—Optical coatings produced by application to, or surface treatment of, optical elements
    • G02B1/14—Protective coatings, e.g. hard coatings
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements

Definitions

  • Polyvinyl alcohol (PVA) is mainly used for polarizing plates used in display devices. Since PVA has extremely poor water resistance, protective films are attached to both sides of the film. Conventionally, hard coat films with moisture permeability of about 300 to 1000 g/m 2 /day, which are made by laminating a hard coat layer on a triacetyl cellulose (TAC) film, have been used as protective films for polarizing plates. However, under harsh conditions of high temperature and humidity, the PVA cannot completely prevent water absorption, which causes degradation.
  • TAC triacetyl cellulose
  • the present invention therefore aims to provide a polarizing plate that is durable in high-temperature, high-humidity environments and a display device that uses the same.
  • the polarizing plate according to the present invention is a polarizing plate having a protective film A bonded to one surface of a polarizer and a protective film B bonded to the other surface thereof, wherein the protective film A is a hard coat film having a hard coat layer formed on one surface of a transparent substrate, and the moisture permeability TA of the protective film A and the moisture permeability TB of the protective film B at 40°C and 90% RH simultaneously satisfy the following conditions (1) and (2), and when the peak intensity at 1782 to 1683 cm -1 measured by the ATR method using a germanium prism is P1 and the peak intensity at 1427 to 1374 cm -1 is P2, the polarizing plate satisfies the following condition (3): 240 g/m 2 /day>TA>70 g/m 2 /day ... (1) 70 g/m 2 /day ⁇ TB (2) 0.060 ⁇ P2/P1 ⁇ 0.150 (3)
  • the display device according to the present invention is equipped with the above polarizing plate.
  • the present invention provides a polarizing plate that is durable in high-temperature, high-humidity environments, and a display device using the same.
  • FIG. 1 is a cross-sectional view showing a schematic configuration of a polarizing plate according to an embodiment of the present invention.
  • FIG. 1 is a cross-sectional view showing the schematic configuration of a polarizing plate according to an embodiment.
  • the protective film A can be formed by applying a composition for forming a hard coat layer, which contains an active energy ray-curable compound, a hydrophobic material, a photopolymerization initiator, and a solvent, to one side of the transparent substrate 2, drying the composition, and curing the coating by irradiating it with ultraviolet light.
  • a composition for forming a hard coat layer which contains an active energy ray-curable compound, a hydrophobic material, a photopolymerization initiator, and a solvent
  • trifunctional or higher (meth)acrylates examples include trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, tris-2-hydroxyethyl isocyanurate tri(meth)acrylate, glycerin tri(meth)acrylate, and other trifunctional (meth)acrylate compounds such as pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, and ditrimethylolpropane tri(meth)acrylate.
  • urethane (meth)acrylate can be used as a polyfunctional monomer.
  • urethane (meth)acrylate include those obtained by reacting a polyester polyol with an isocyanate monomer or a prepolymer, and then reacting the resulting product with a (meth)acrylate monomer having a hydroxyl group.
  • urethane (meth)acrylates examples include pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate hexamethylene diisocyanate urethane prepolymer, pentaerythritol triacrylate toluene diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate toluene diisocyanate urethane prepolymer, pentaerythritol triacrylate isophorone diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate isophorone diisocyanate urethane prepolymer, etc.
  • the above-mentioned polyfunctional monomers may be used alone or in combination of two or more.
  • the above-mentioned polyfunctional monomers may be monomers in the composition, or may be partially polymerized oligomers.
  • the hydrophobic material is a component that imparts hydrophobicity to the hard coat layer 3 and adjusts the moisture permeability of the protective film A.
  • a cycloolefin polymer or a (meth)acrylate containing an alicyclic structure can be used as the hydrophobic material contained in the hard coat layer 3.
  • the (meth)acrylate containing an alicyclic structure for example, a (meth)acrylate having one or more of a cyclopentane structure, a dicyclopentane structure, a cyclohexane structure, a cyclodecane structure, a tricyclodecane structure, an isobornyl structure, and an adamantane structure can be used.
  • (meth)acrylates containing an alicyclic structure include cyclohexyl (meth)acrylate, cyclohexanedimethanol mono(meth)acrylate, 4-tert-butylcyclohexyl (meth)acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, 3,3,5-trimethylcyclohexanol (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and dicyclopentadienyl (meth)acrylate.
  • monofunctional (meth)acrylates such as 2-dicyclopentenoxyethyl (meth)acrylate, dicyclopentenyloxyethyl methacrylate, bornyl (meth)acrylate, isobornyl (meth)acrylate, tricyclodecanyl (meth)acrylate, tricyclodecane dimethanol mono(meth)acrylate, and adamantyl (meth)acrylate; cyclohexane dimethanol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, dicyclopentanyl methacrylate, and the like; dicyclopentadienyl di(meth)acrylate, bornyl di(meth)acrylate, isobornyl di(meth)acrylate, tricyclodecanyl di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, adamantyl di(meth)acrylate, adamantane dimethanol di(meth
  • radical polymerization initiators such as acetophenone, benzophenone, thioxanthone, benzoin, benzoin methyl ether, and acylphosphine oxide can be used.
  • a polymerization initiator for example, diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-phenylacetophenone, dibenzoyl, benzoin, benzoin methyl ether, benzoin ethyl ether, p-chlorobenzophenone, p-methoxybenzophenone, Michler's ketone, acetophenone, and 2-chlorothioxanthone can be used.
  • One of these may be used alone, or two or more may be
  • additives such as antistatic agents, defoamers, antioxidants, ultraviolet absorbers, infrared absorbers, colorants, light stabilizers, polymerization inhibitors, photosensitizers, antifouling agents, leveling agents, oil repellents, water repellents, and fingerprint prevention agents may be added to the composition for forming the hard coat layer as necessary.
  • the method for applying the composition for forming the hard coat layer is not particularly limited, and for example, it can be applied using a spin coater, roll coater, reverse roll coater, gravure coater, microgravure coater, knife coater, bar coater, wire bar coater, die coater, dip coater, spray coater, applicator, etc.
  • the coating thickness of the composition for forming a hard coat layer is preferably 10 ⁇ m or less, and more preferably 8 ⁇ m or less. If the coating thickness of the composition for forming a hard coat layer exceeds 10 ⁇ m, curling is likely to occur due to shrinkage during curing, which is not preferred.
  • the pencil hardness of protective film A is 3H or more.
  • the polarizing plate has excellent surface hardness and improved durability.
  • Protective film B is a low moisture permeable film made of any one of cycloolefin polymer (COP), polyethylene terephthalate (PET), and polymethyl methacrylate (PMMA).
  • COP cycloolefin polymer
  • PET polyethylene terephthalate
  • PMMA polymethyl methacrylate
  • Protective film B is attached to polarizer 1 via, for example, an ultraviolet-curable adhesive.
  • the thickness of protective film B is not particularly limited, but is preferably 10 to 100 ⁇ m.
  • protective film B is disposed on the display panel side, and hard coat layer 3 of protective film A is disposed on the viewing side (the side opposite the display panel).
  • the transparent substrate 2 of the protective film A is bonded to the PVA film of the polarizer 1 using a water-based adhesive (aqueous PVA solution).
  • a water-based adhesive aqueous PVA solution
  • the protective film A is subjected to a saponification treatment before bonding. Because water-based adhesive is used to bond the protective film A to the polarizer 1, moisture may be present in the adhesive layer and the TAC film even after a drying process.
  • both protective films A and B are made of films with low moisture permeability, the intrusion of moisture from the outside is suppressed, but in extremely high-temperature environments such as the inside of a car in summer, moisture contained in the adhesive and/or transparent substrate 2 will remain in the polarizer 10, causing deterioration of the polarizer 1.
  • a difference is provided between the moisture permeability of protective film A and that of protective film B, and the moisture permeability of protective film A and protective film B are each set to a specific range, thereby suppressing deterioration of the polarizer 1 due to moisture from the adhesive and/or TAC film.
  • both of the moisture permeabilities TA and TB are values measured in accordance with the moisture permeability test method (cup method) for moisture-proof packaging materials specified in JIS Z 0208:1976. 240 g/m 2 /day>TA>70 g/m 2 /day ... (1) 70 g/m 2 /day ⁇ TB (2)
  • the polarizing plate 10 simultaneously satisfies the above conditions (1) and (2), and thus is able to suppress the intrusion of moisture from the outside into the polarizing plate, while at the same time allowing moisture generated from the adhesive used to bond the protective film A and the polarizer 1 and/or the transparent substrate 2 of the protective film A to be discharged to the outside when exposed to a high-temperature environment, for example, at 85°C.
  • the peak intensity (peak height) at 1782 to 1683 cm ⁇ 1 measured by the ATR method using a germanium prism is defined as P1
  • the peak intensity at 1427 to 1374 cm ⁇ 1 is defined as P2
  • P2/P1 is defined as the degree of cure.
  • the degree of cure P2/P1 of the hard coat layer 3 becomes small, the pencil hardness increases, and when the degree of cure P2/P1 becomes large, the pencil hardness decreases. Also, when the value of the degree of cure P2/P1 becomes small, the moisture permeability decreases, and when the value of the degree of cure P2/P1 becomes large, the moisture permeability tends to increase. Therefore, there exists a range of the degree of curing P2/P1 that can achieve both pencil hardness and moisture permeability, and specifically, it is preferable that the degree of curing P2/P1 satisfies the following condition (3). 0.060 ⁇ P2/P1 ⁇ 0.150 (3)
  • the degree of curing P2/P1 When the degree of curing P2/P1 is less than 0.060, the moisture permeability of the protective film A becomes too low, and the above condition (1) may not be satisfied. In this case, the moisture generated from the transparent substrate 2 of the protective film A cannot be discharged to the outside.
  • the degree of curing P2/P1 exceeds 0.150, the pencil hardness of the protective film A deteriorates. In addition, the moisture permeability becomes too high, and the above condition (1) may not be satisfied. In this case, it is difficult to suppress the intrusion of moisture from the outside into the polarizing plate.
  • condition (1) is more preferably 239.7 g/m 2 / day ⁇ TA ⁇ 93.5 g/m 2 /day, more preferably 212 g/m 2 /day ⁇ TA ⁇ 152.9 g/ m 2 /day, and more preferably 191.7 g/m 2 /day ⁇ TA ⁇ 152.9 g/ m 2 /day.
  • condition (3) is more preferably 0.067 ⁇ P2/P1 ⁇ 0.149, more preferably 0.101 ⁇ P2/P1 ⁇ 0.137, and even more preferably 0.101 ⁇ P2/P1 ⁇ 0.126.
  • the polarizing plate 10 includes protective film A and protective film B that satisfy the above conditions (1) to (3).
  • protective film B arranged on the display panel side almost completely blocks the ingress and egress of moisture.
  • protective film A arranged on the viewing side allows the release of moisture generated inside the polarizing plate 10 in an extremely high-temperature environment while suppressing the ingress of moisture into the polarizing plate 10 from the outside. Therefore, in the polarizing plate 10 according to this embodiment, when used in a high-temperature environment, moisture generated inside the polarizing plate 10 does not remain, suppressing deterioration of the polarizer and making it possible to maintain the optical performance of the polarizing plate 10 for a longer period of time.
  • this embodiment can provide a polarizing plate 10 that has excellent durability in high-temperature and high-humidity environments.
  • the polarizing plate 10 according to this embodiment can be used in combination with an image display panel such as a liquid crystal panel or an organic EL panel to form an image display device.
  • the image display device may also include a touch panel.
  • the polarizing plate 10 according to this embodiment has excellent durability in high temperature and high humidity environments, and can therefore be suitably used as an image display device to be installed in environments such as the inside of a vehicle, which can be extremely hot and humid.
  • a composition for forming a hard coat layer was prepared containing the main material (polymerizable material), hydrophobic material, photopolymerization initiator, and solvent in the ratios shown in Table 1.
  • Irgacure (registered trademark) 184 shown in Table 1 is 1-hydroxycyclohexyl phenyl ketone.
  • the prepared composition for forming a hard coat layer was applied to a 40 ⁇ m-thick TAC film (product name: TJ40, manufactured by Fujifilm Corporation) using a wire bar coater to the coating thickness shown in Table 2.
  • the coating was dried by heating in an oven at 60°C for 1 minute, and then cured by irradiating ultraviolet light in a nitrogen atmosphere (oxygen concentration 500 ppm or less) in a UV curing device to produce protective film A (hard coat film) according to Examples 1 to 6 and Comparative Examples 1 to 7.
  • a 60 ⁇ m-thick polymethyl methacrylate (PMMA) film and a 26 ⁇ m-thick cycloolefin polymer (COP) film were used as protective film A.
  • a 26 ⁇ m-thick COP film was used as protective film B.
  • protective film A was attached to the polarizer using water-based glue and dried, after which protective film B was attached to the polarizer using a UV-curable adhesive, and the UV-curable adhesive was cured by irradiating it with UV light to obtain a polarizing plate.
  • protective film A was used as protective film B.
  • the hard coat layer of the protective film A was subjected to FT-IR analysis by the ATR method. From the FT-IR measurement results, the peak height P1 at 1782 to 1683 cm -1 and the peak height P2 at 1427 to 1374 cm -1 were obtained, and the degree of cure P2/P1 was calculated. At this time, an FT/IR-610 manufactured by JASCO Corporation was used as the infrared spectrometer, and a germanium prism was used as the prism.
  • the polarizing plates according to each of the Examples and Comparative Examples were placed in a thermostatic chamber at 85° C. and 85% RH, and the polarization degree was measured 240 hours and 500 hours after the placement.
  • the polarization degree was calculated by performing luminosity correction using a 2-degree visual field (C light source) according to JIS Z 8701 for a value measured using an absorptiometer with an integrating sphere (V7100, manufactured by JASCO Corporation).
  • Table 2 shows the characteristics of protective films A and B for each example and comparative example, as well as the measured polarization degree of the polarizing plate (initial value, before and after the high temperature and high humidity durability test).
  • the polarizing plates according to Examples 1 to 6 have a moisture permeability TA of protective film A and a moisture permeability TB of protective film B that satisfy the above conditions (1) and (2), and furthermore, the degree of hardening of the hard coat layer of protective film A satisfies the above condition (3). Therefore, even after being placed in a thermostatic chamber at 85°C and 85% RH for 500 hours, they showed a high degree of polarization and good surface hardness.
  • Comparative Examples 6 and 7 a PMMA film and a COP film with extremely low moisture permeability TA were used as protective film A, respectively, but the polarization degree deteriorated after being placed in a thermostatic chamber at 85°C and 85% RH for 500 hours. This is thought to be because the moisture permeability TA of protective film A was too low, and when exposed to high temperature and humidity, the moisture contained in protective film A and/or the adhesive (water glue) continued to remain in the polarizing plate, causing deterioration of the polarizer.
  • protective film A in Comparative Examples 6 and 7 did not have a hard coat layer, so its surface hardness was inferior to that of the Examples.
  • the present invention can be used as a polarizing plate for display devices, and is particularly suitable as a polarizing plate for display devices used in high-temperature environments such as in-vehicle applications.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Polarising Elements (AREA)
  • Laminated Bodies (AREA)

Abstract

The present invention provides a polarizing plate having durability in high-temperature and high-humidity environments, and a display device using the same. Provided is a polarizing plate in which a protective film A is affixed to one surface of a polarizer and a protective film B is affixed to the other surface, wherein: the protective film A is a hard coat film in which a hard coat layer is formed on one surface of a transparent base material; the moisture permeability TA of the protective film A and the moisture permeability TB of the protective film B at 40°C and 90% RH satisfy conditions (1) and (2) simultaneously; and, when P1 is defined as the peak intensity for 1782-1683 cm-1 and P2 is defined as the peak intensity for 1427-1374 cm-1 as measured via an ATR method using a germanium prism, condition (3) is satisfied.　(1): 240g/m2/day>TA>70g/m2/day. (2): 70g/m2/day≥TB. (3): 0.060≤P2/P1≤0.150

Description

偏光板及びこれを用いた表示装置Polarizing plate and display device using the same
　本発明は、偏光板及びこれを用いた表示装置に関する。 The present invention relates to a polarizing plate and a display device using the same.
　表示装置に用いられる偏光板には、主にポリビニルアルコール（ＰＶＡ）が使用されている。ＰＶＡは耐水性が極めて悪いため、両面に保護フィルムが貼り合わされる。偏光板の保護フィルムには、従来、トリアセチルセルロース（ＴＡＣ）フィルムにハードコート層を積層した、透湿度が３００～１０００ｇ／ｍ２／ｄａｙ程度のハードコートフィルムが使用されてきたが、高温高湿の過酷条件下では、ＰＶＡの吸水を防ぎきれずに劣化を引き起こすという問題であった。 Polyvinyl alcohol (PVA) is mainly used for polarizing plates used in display devices. Since PVA has extremely poor water resistance, protective films are attached to both sides of the film. Conventionally, hard coat films with moisture permeability of about 300 to 1000 g/m 2 /day, which are made by laminating a hard coat layer on a triacetyl cellulose (TAC) film, have been used as protective films for polarizing plates. However, under harsh conditions of high temperature and humidity, the PVA cannot completely prevent water absorption, which causes degradation.
　そこで、ＴＡＣに代えて、シクロオレフィンポリマー（ＣＯＰ）や、ポリエチレンテレフタレート（ＰＥＴ）を用いた保護フィルムの開発が進められ、保護フィルムの透湿度は、５～１００ｇ／ｍ２／ｄａｙ程度まで低減されてきた。 Therefore, instead of TAC, protective films using cycloolefin polymer (COP) or polyethylene terephthalate (PET) have been developed, and the moisture permeability of the protective films has been reduced to about 5 to 100 g/m 2 /day.
特開２０２１－１４４０７６号公報JP 2021-144076 A
　近年、車載用途などで、極めて高い温湿度での耐久性を有する偏光板が求められている。高温湿度環境下において、保護フィルムの水蒸気バリア性が高すぎると、外部からの水分の侵入はないものの、基材や、保護フィルムの貼り合わせに用いた粘着剤から発生した水分が、偏光板中に留まり劣化を引き起こすという事例が観測されている。 In recent years, there has been a demand for polarizing plates that are durable under extremely high temperatures and humidity, such as for in-vehicle applications. In high-temperature and humid environments, if the water vapor barrier properties of the protective film are too high, moisture will not penetrate from the outside, but there have been observed cases where moisture generated from the base material and the adhesive used to attach the protective film remains in the polarizing plate and causes degradation.
　それ故に、本発明は、高温高湿環境における耐久性を備えた偏光板及びこれを用いた表示装置を提供することを目的とする。 The present invention therefore aims to provide a polarizing plate that is durable in high-temperature, high-humidity environments and a display device that uses the same.
　本発明に係る偏光板は、偏光子の一方面に保護フィルムＡが貼り合わされ、他方面に保護フィルムＢが貼り合わされた偏光板であって、保護フィルムＡが、透明基材の一面にハードコート層が形成されたハードコートフィルムであり、４０℃９０％ＲＨにおける保護フィルムＡの透湿度ＴＡ及び保護フィルムＢの透湿度ＴＢが以下の条件（１）及び（２）を同時に満足し、ＡＴＲ法でゲルマニウムプリズムを用いて測定した１７８２～１６８３ｃｍ－１のピーク強度をＰ１、１４２７～１３７４ｃｍ－１のピーク強度をＰ２としたとき、以下の条件（３）を満足する。
　　２４０ｇ／ｍ２／ｄａｙ＞ＴＡ＞７０ｇ／ｍ２／ｄａｙ　・・・（１）
　　７０ｇ／ｍ２／ｄａｙ≧ＴＢ　・・・（２）
　　０．０６０≦Ｐ２／Ｐ１≦０．１５０　・・・（３） The polarizing plate according to the present invention is a polarizing plate having a protective film A bonded to one surface of a polarizer and a protective film B bonded to the other surface thereof, wherein the protective film A is a hard coat film having a hard coat layer formed on one surface of a transparent substrate, and the moisture permeability TA of the protective film A and the moisture permeability TB of the protective film B at 40°C and 90% RH simultaneously satisfy the following conditions (1) and (2), and when the peak intensity at 1782 to 1683 cm -1 measured by the ATR method using a germanium prism is P1 and the peak intensity at 1427 to 1374 cm -1 is P2, the polarizing plate satisfies the following condition (3):
240 g/m 2 /day>TA>70 g/m 2 /day ... (1)
70 g/m 2 /day≧TB (2)
0.060≦P2/P1≦0.150 (3)
　また、本発明に係る表示装置は、上記の偏光板を備えるものである。 The display device according to the present invention is equipped with the above polarizing plate.
　本発明によれば、高温高湿環境における耐久性を備えた偏光板及びこれを用いた表示装置を提供できる。 The present invention provides a polarizing plate that is durable in high-temperature, high-humidity environments, and a display device using the same.
図１は、実施形態に係る偏光板の概略構成を示す断面図である。FIG. 1 is a cross-sectional view showing a schematic configuration of a polarizing plate according to an embodiment of the present invention.
　図１は、実施形態に係る偏光板の概略構成を示す断面図である。 FIG. 1 is a cross-sectional view showing the schematic configuration of a polarizing plate according to an embodiment.
　偏光板１０は、偏光子１と、偏光子１の一方面側に貼り合わされる保護フィルムＡと、偏光子１の他方面側に貼り合わされる保護フィルムＢとを備える。偏光子１は、ポリビニルアルコール（ＰＶＡ）フィルムにヨウ素または染料を吸着させ配向させることによって形成されたものである。偏光子１を構成するＰＶＡは、強度及び耐水性に劣るため、偏光子１の両面に保護フィルムＡ及びＢが貼り合わされる。 The polarizing plate 10 comprises a polarizer 1, a protective film A attached to one side of the polarizer 1, and a protective film B attached to the other side of the polarizer 1. The polarizer 1 is formed by adsorbing iodine or a dye onto a polyvinyl alcohol (PVA) film and orienting it. The PVA that constitutes the polarizer 1 has poor strength and water resistance, so protective films A and B are attached to both sides of the polarizer 1.
　保護フィルムＡは、透明基材２の一面にハードコート層３が形成されたハードコートフィルムである。ハードコート層３は、柔軟な透明基材２を覆い、保護フィルムＡに硬度と水蒸気バリア性を付与する機能層である。透明基材２としては、透明性に優れるトリアセチルセルロース（ＴＡＣ）フィルムを好適に使用することができる。 Protective film A is a hard coat film in which a hard coat layer 3 is formed on one surface of a transparent substrate 2. The hard coat layer 3 is a functional layer that covers the flexible transparent substrate 2 and imparts hardness and water vapor barrier properties to protective film A. A triacetyl cellulose (TAC) film, which has excellent transparency, can be suitably used as the transparent substrate 2.
　保護フィルムＡは、活性エネルギー線硬化型化合物と、疎水性材料と、光重合開始剤と、溶剤とを含有するハードコート層形成用組成物を透明基材２の一面に塗布して乾燥させ、紫外線照射により塗膜を硬化させることによって形成することができる。 The protective film A can be formed by applying a composition for forming a hard coat layer, which contains an active energy ray-curable compound, a hydrophobic material, a photopolymerization initiator, and a solvent, to one side of the transparent substrate 2, drying the composition, and curing the coating by irradiating it with ultraviolet light.
　活性エネルギー線硬化型化合物としては、例えば、単官能、２官能または３官能以上の（メタ）アクリレートモノマーを使用できる。尚、本明細書において、「（メタ）アクリレート」は、アクリレートとメタクリレートの両方の総称であり、「（メタ）アクリロイル」は、アクリロイルとメタクリロイルの両方の総称である。 As the active energy ray curable compound, for example, a monofunctional, difunctional, trifunctional or higher functional (meth)acrylate monomer can be used. In this specification, "(meth)acrylate" is a general term for both acrylate and methacrylate, and "(meth)acryloyl" is a general term for both acryloyl and methacryloyl.
　単官能の（メタ）アクリレート化合物の例としては、２－ヒドロキシエチル（メタ）アクリレート、２－ヒドロキシプロピル（メタ）アクリレート、２－ヒドロキシブチル（メタ）アクリレート、ｎ－ブチル（メタ）アクリレート、イソブチル（メタ）アクリレート、ｔ－ブチル（メタ）アクリレート、グリシジル（メタ）アクリレート、アクリロイルモルフォリン、Ｎ－ビニルピロリドン、テトラヒドロフルフリールアクリレート、シクロヘキシル（メタ）アクリレート、２－エチルヘキシル（メタ）アクリレート、イソボルニル（メタ）アクリレート、イソデシル（メタ）アクリレート、ラウリル（メタ）アクリレート、トリデシル（メタ）アクリレート、セチル（メタ）アクリレート、ステアリル（メタ）アクリレート、ベンジル（メタ）アクリレート、２－エトキシエチル（メタ）アクリレート、３－メトキシブチル（メタ）アクリレート、エチルカルビトール（メタ）アクリレート、リン酸（メタ）アクリレート、エチレンオキサイド変性リン酸（メタ）アクリレート、フェノキシ（メタ）アクリレート、エチレンオキサイド変性フェノキシ（メタ）アクリレート、プロピレンオキサイド変性フェノキシ（メタ）アクリレート、ｂフェノール（メタ）アクリレート、エチレンオキサイド変性ノニルフェノール（メタ）アクリレート、プロピレンオキサイド変性ノニルフェノール（メタ）アクリレート、メトキシジエチレングリコール（メタ）アクリレート、メトキシポリチレングリコール（メタ）アクリレート、メトキシプロピレングリコール（メタ）アクリレート、２－（メタ）アクリロイルオキシエチル－２－ヒドロキシプロピルフタレート、２－ヒドロキシ－３－フェノキシプロピル（メタ）アクリレート、２－（メタ）アクリロイルオキシエチルハイドロゲンフタレート、２－（メタ）アクリロイルオキシプロピルハイドロゲンフタレート、２－（メタ）アクリロイルオキシプロピルヘキサヒドロハイドロゲンフタレート、２－（メタ）アクリロイルオキシプロピルテトラヒドロハイドロゲンフタレート、ジメチルアミノエチル（メタ）アクリレート、トリフルオロエチル（メタ）アクリレート、テトラフルオロプロピル（メタ）アクリレート、ヘキサフルオロプロピル（メタ）アクリレート、オクタフルオロプロピル（メタ）アクリレート、２－アダマンタン、アダマンタンジオールから誘導される１価のモノ（メタ）アクリレートを有するアダマンチルアクリレート等のアダマンタン誘導体モノ（メタ）アクリレート等が挙げられる。 Examples of monofunctional (meth)acrylate compounds include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, glycidyl (meth)acrylate, acryloylmorpholine, N-vinylpyrrolidone, tetrahydrofurfuryl acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isobornyl (meth)acrylate, and isodecyl (meth)acrylate. , lauryl (meth)acrylate, tridecyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylate, phosphate (meth)acrylate, ethylene oxide modified phosphate (meth)acrylate, phenoxy (meth)acrylate, ethylene oxide modified phenoxy (meth)acrylate, propylene oxide modified phenoxy (meth)acrylate, b-phenol (meth)acrylate, ethylene nonylphenol (meth)acrylate modified with ethylene oxide, nonylphenol (meth)acrylate modified with propylene oxide, methoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypropylene glycol (meth)acrylate, 2-(meth)acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-(meth)acryloyloxyethyl hydrogen phthalate, 2-(meth)acryloyloxypropyl hydrogen phthalate, 2-(meth)acryloyloxyethyl hydrogen phthalate, p) Acryloyloxypropyl hexahydrohydrogen phthalate, 2-(meth)acryloyloxypropyl tetrahydrohydrogen phthalate, dimethylaminoethyl (meth)acrylate, trifluoroethyl (meth)acrylate, tetrafluoropropyl (meth)acrylate, hexafluoropropyl (meth)acrylate, octafluoropropyl (meth)acrylate, 2-adamantane, adamantane derivative mono(meth)acrylates such as adamantyl acrylate having a monovalent mono(meth)acrylate derived from adamantanediol, etc.
　２官能の（メタ）アクリレートの例としては、エチレングリコールジ（メタ）アクリレート、ジエチレングリコールジ（メタ）アクリレート、ブタンジオールジ（メタ）アクリレート、ヘキサンジオールジ（メタ）アクリレート、ノナンジオールジ（メタ）アクリレート、エトキシ化ヘキサンジオールジ（メタ）アクリレート、プロポキシ化ヘキサンジオールジ（メタ）アクリレート、ジエチレングリコールジ（メタ）アクリレート、ポリエチレングリコールジ（メタ）アクリレート、トリプロピレングリコールジ（メタ）アクリレート、ポリプロピレングリコールジ（メタ）アクリレート、ネオペンチルグリコ－ルジ（メタ）アクリレート、エトキシ化ネオペンチルグリコールジ（メタ）アクリレート、トリプロピレングリコールジ（メタ）アクリレート、ヒドロキシピバリン酸ネオペンチルグリコールジ（メタ）アクリレート等のジ（メタ）アクリレート等が挙げられる。 Examples of bifunctional (meth)acrylates include di(meth)acrylates such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate, nonanediol di(meth)acrylate, ethoxylated hexanediol di(meth)acrylate, propoxylated hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethoxylated neopentyl glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, and hydroxypivalic acid neopentyl glycol di(meth)acrylate.
　３官能以上の（メタ）アクリレートの例としては、トリメチロールプロパントリ（メタ）アクリレート、エトキシ化トリメチロールプロパントリ（メタ）アクリレート、プロポキシ化トリメチロールプロパントリ（メタ）アクリレート、トリス２－ヒドロキシエチルイソシアヌレートトリ（メタ）アクリレート、グリセリントリ（メタ）アクリレート等のトリ（メタ）アクリレート、ペンタエリスリトールトリ（メタ）アクリレート、ジペンタエリスリトールトリ（メタ）アクリレート、ジトリメチロールプロパントリ（メタ）アクリレート等の３官能の（メタ）アクリレート化合物や、ペンタエリスリトールテトラ（メタ）アクリレート、ジトリメチロールプロパンテトラ（メタ）アクリレート、ジペンタエリスリトールテトラ（メタ）アクリレート、ジペンタエリスリトールペンタ（メタ）アクリレート、ジトリメチロールプロパンペンタ（メタ）アクリレート、ジペンタエリスリトールヘキサ（メタ）アクリレート、ジトリメチロールプロパンヘキサ（メタ）アクリレート等の３官能以上の多官能（メタ）アクリレート化合物や、これら（メタ）アクリレートの一部をアルキル基やε－カプロラクトンで置換した多官能（メタ）アクリレート化合物等が挙げられる。 Examples of trifunctional or higher (meth)acrylates include trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, tris-2-hydroxyethyl isocyanurate tri(meth)acrylate, glycerin tri(meth)acrylate, and other trifunctional (meth)acrylate compounds such as pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, and ditrimethylolpropane tri(meth)acrylate. Examples of such compounds include trifunctional or higher polyfunctional (meth)acrylate compounds such as pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, ditrimethylolpropane penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and ditrimethylolpropane hexa(meth)acrylate, as well as polyfunctional (meth)acrylate compounds in which a portion of these (meth)acrylates is substituted with an alkyl group or ε-caprolactone.
　また、多官能モノマーとして、ウレタン（メタ）アクリレートも使用できる。ウレタン（メタ）アクリレートとしては、例えば、ポリエステルポリオールにイソシアネートモノマー、もしくはプレポリマーを反応させて得られた生成物に水酸基を有する（メタ）アクリレートモノマーを反応させることによって得られるものを挙げることができる。 Also, as a polyfunctional monomer, urethane (meth)acrylate can be used. Examples of urethane (meth)acrylate include those obtained by reacting a polyester polyol with an isocyanate monomer or a prepolymer, and then reacting the resulting product with a (meth)acrylate monomer having a hydroxyl group.
　ウレタン（メタ）アクリレートの例としては、ペンタエリスリトールトリアクリレートヘキサメチレンジイソシアネートウレタンプレポリマー、ジペンタエリスリトールペンタアクリレートヘキサメチレンジイソシアネートウレタンプレポリマー、ペンタエリスリトールトリアクリレートトルエンジイソシアネートウレタンプレポリマー、ジペンタエリスリトールペンタアクリレートトルエンジイソシアネートウレタンプレポリマー、ペンタエリスリトールトリアクリレートイソホロンジイソシアネートウレタンプレポリマー、ジペンタエリスリトールペンタアクリレートイソホロンジイソシアネートウレタンプレポリマー等が挙げられる。 Examples of urethane (meth)acrylates include pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate hexamethylene diisocyanate urethane prepolymer, pentaerythritol triacrylate toluene diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate toluene diisocyanate urethane prepolymer, pentaerythritol triacrylate isophorone diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate isophorone diisocyanate urethane prepolymer, etc.
　上述した多官能モノマーは１種を用いても良いし、２種以上を組み合わせて用いても良い。また、上述した多官能モノマーは、組成物中でモノマーであっても良いし、一部が重合したオリゴマーであっても良い。 The above-mentioned polyfunctional monomers may be used alone or in combination of two or more. In addition, the above-mentioned polyfunctional monomers may be monomers in the composition, or may be partially polymerized oligomers.
　疎水性材料は、ハードコート層３に疎水性を発現させ、保護フィルムＡの透湿度を調節するための成分である。ハードコート層３に含有させる疎水性材料としては、シクロオレフィンポリマーや、脂環式構造を含む（メタ）アクリレートを使用することができる。 The hydrophobic material is a component that imparts hydrophobicity to the hard coat layer 3 and adjusts the moisture permeability of the protective film A. As the hydrophobic material contained in the hard coat layer 3, a cycloolefin polymer or a (meth)acrylate containing an alicyclic structure can be used.
　脂環式構造を含む（メタ）アクリレートとしては、例えば、シクロペンタン構造、ジシクロペンタン構造、シクロヘキサン構造、シクロデカン構造、トリシクロデカン構造、イソボルニル構造、アダマンタン構造の１種以上を有する（メタ）アクリレートを使用することができる。 As the (meth)acrylate containing an alicyclic structure, for example, a (meth)acrylate having one or more of a cyclopentane structure, a dicyclopentane structure, a cyclohexane structure, a cyclodecane structure, a tricyclodecane structure, an isobornyl structure, and an adamantane structure can be used.
　脂環式構造を含む（メタ）アクリレートの具体例として、シクロヘキシル（メタ）アクリレート、シクロヘキサンジメタノールモノ（メタ）アクリレート、４－ｔｅｒｔ－ブチルシクロヘキシル（メタ）アクリレート、３，３，５－トリメチルシクロヘキシル（メタ）アクリレート、３，３，５－トリメチルシクロヘキサノール（メタ）アクリレート、ジシクロペンタニル（メタ）アクリレート、ジシクロペンテニル（メタ）アクリレート、ジシクロペンタジエニル（メタ）アクリレート、２－ジシクロペンテノキシエチル（メタ）アクリレート、ジシクロペンテニルオキシエチルメタクリレート、ボルニル（メタ）アクリレート、イソボルニル（メタ）アクリレート、トリシクロデカニル（メタ）アクリレート、トリシクロデカンジメタノールモノ（メタ）アクリレート、アダマンチル（メタ）アクリレート等の単官能（メタ）アクリレートや、シクロヘキサンジメタノールジ（メタ）アクリレート、ジシクロペンタニルジ（メタ）アクリレート、ジシクロペンテニルジ（メタ）アクリレート、ジシクロペンタジエニルジ（メタ）アクリレート、ボルニルジ（メタ）アクリレート、イソボルニルジ（メタ）アクリレート、トリシクロデカニルジ（メタ）アクリレート、トリシクロデカンジメタノールジ（メタ）アクリレート、アダマンチルジ（メタ）アクリレート、アダマンタンジメタノールジ（メタ）アクリレート、アダマンタンジエタノールジ（メタ）アクリレート、ジメチロールジシクロペンタンジ（メタ）アクリレート、ノルボルナンジメチロールジ（メタ）アクリレート、シクロヘキサントリメタノールトリ（メタ）アクリレート、アダマンチルトリ（メタ）アクリレート、アダマンタントリメタノールトリ（メタ）アクリレート、ノルボルナントリメチロールトリ（メタ）アクリレート、トリシクロデカントリメタノールトリ（メタ）アクリレート、パーヒドロ－１，４，５，８－ジメタノナフタレン－２，３，７－（オキシメチル）トリ（メタ）アクリレート等の多官能（メタ）アクリレートが挙げられる。これらの（メタ）アクリレートは、単独で使用しても良いし、１種以上を混合して使用しても良い。 Specific examples of (meth)acrylates containing an alicyclic structure include cyclohexyl (meth)acrylate, cyclohexanedimethanol mono(meth)acrylate, 4-tert-butylcyclohexyl (meth)acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, 3,3,5-trimethylcyclohexanol (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and dicyclopentadienyl (meth)acrylate. monofunctional (meth)acrylates such as 2-dicyclopentenoxyethyl (meth)acrylate, dicyclopentenyloxyethyl methacrylate, bornyl (meth)acrylate, isobornyl (meth)acrylate, tricyclodecanyl (meth)acrylate, tricyclodecane dimethanol mono(meth)acrylate, and adamantyl (meth)acrylate; cyclohexane dimethanol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, dicyclopentanyl methacrylate, and the like; dicyclopentadienyl di(meth)acrylate, bornyl di(meth)acrylate, isobornyl di(meth)acrylate, tricyclodecanyl di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, adamantyl di(meth)acrylate, adamantane dimethanol di(meth)acrylate, adamantane diethanol di(meth)acrylate, dimethylol dicyclopentane di(meth)acrylate, norborna Examples of the polyfunctional (meth)acrylates include dimethylol di(meth)acrylate, cyclohexane trimethanol tri(meth)acrylate, adamantyl tri(meth)acrylate, adamantane trimethanol tri(meth)acrylate, norbornane trimethylol tri(meth)acrylate, tricyclodecane trimethanol tri(meth)acrylate, and perhydro-1,4,5,8-dimethanonaphthalene-2,3,7-(oxymethyl) tri(meth)acrylate. These (meth)acrylates may be used alone or in combination of one or more.
　光重合開始剤としては、アセトフェノン系、ベンゾフェノン系、チオキサントン系、ベンゾイン、ベンゾインメチルエーテル、アシルフォスフィンオキシド等のラジカル重合開始剤に使用することができる。重合開始剤として、例えば、ジフェニル（２，４，６－トリメチルベンゾイル）ホスフィンオキシド、ビス（２，４，６－トリメチルベンゾイル）フェニルホスフィンオキシド、２，２－ジエトキシアセトフェノン、１－ヒドロキシシクロヘキシルフェニルケトン、２，２－ジメトキシ－フェニルアセトフェノン、ジベンゾイル、ベンゾイン、ベンゾインメチルエーテル、ベンゾインエチルエーテル、ｐ－クロロベンゾフェノン、ｐ－メトキシベンゾフェノン、ミヒラーケトン、アセトフェノン、２－クロロチオキサントン等を使用できる。これらのうち１種類を単独で使用しても良いし、２種類以上を組み合わせて使用しても良い。 As a photopolymerization initiator, radical polymerization initiators such as acetophenone, benzophenone, thioxanthone, benzoin, benzoin methyl ether, and acylphosphine oxide can be used. As a polymerization initiator, for example, diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-phenylacetophenone, dibenzoyl, benzoin, benzoin methyl ether, benzoin ethyl ether, p-chlorobenzophenone, p-methoxybenzophenone, Michler's ketone, acetophenone, and 2-chlorothioxanthone can be used. One of these may be used alone, or two or more may be used in combination.
　溶剤としては、メタノール、エタノール、１－プロパノール、２－プロパノール、ブタノール、イソプロピルアルコール、イソブタノール等のアルコール類、アセトン、メチルエチルケトン、シクロヘキサノン、メチルイソブチルケトン等のケトン類、ジアセトンアルコール等のケトンアルコール類、ベンゼン、トルエン、キシレン等の芳香族炭化水素類、エチレングリコール、プロピレングリコール、ヘキシレングリコール等のグリコール類、エチルセロソルブ、ブチルセロソルブ、エチルカルビトール、ブチルカルビトール、ジエチルセロソルブ、ジエチルカルビトール、プロピレングリコールモノメチルエーテル等のグリコールエーテル類、炭酸ジメチル、乳酸メチル、乳酸エチル、酢酸メチル、酢酸エチル、酢酸ブチル、酢酸アミル等のエステル類、ジメチルエーテル、ジエチルエーテル等のエーテル類、Ｎ－メチルピロリドン、ジメチルフォルムアミド等のうち、１種類または２種類以上を混合して使用できる。 Solvents that can be used alone or in combination of two or more of the following can be used: alcohols such as methanol, ethanol, 1-propanol, 2-propanol, butanol, isopropyl alcohol, isobutanol, etc.; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isobutyl ketone, etc.; ketone alcohols such as diacetone alcohol, etc.; aromatic hydrocarbons such as benzene, toluene, xylene, etc.; glycols such as ethylene glycol, propylene glycol, hexylene glycol, etc.; glycol ethers such as ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, diethyl cellosolve, diethyl carbitol, propylene glycol monomethyl ether, etc.; esters such as dimethyl carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, amyl acetate, etc.; ethers such as dimethyl ether, diethyl ether, etc.; N-methylpyrrolidone, dimethylformamide, etc.
　また、ハードコート層形成用組成物には、帯電防止剤、消泡剤、酸化防止剤、紫外線吸収剤、赤外線吸収剤、色材、光安定剤、重合禁止剤、光増感剤、防汚剤、レベリング剤、撥油剤、撥水剤、指紋付着防止剤等の各種添加剤等を必要に応じて添加しても良い。 Additionally, various additives such as antistatic agents, defoamers, antioxidants, ultraviolet absorbers, infrared absorbers, colorants, light stabilizers, polymerization inhibitors, photosensitizers, antifouling agents, leveling agents, oil repellents, water repellents, and fingerprint prevention agents may be added to the composition for forming the hard coat layer as necessary.
　ハードコート層形成用組成物の塗工方法は特に限定されず、例えば、スピンコーター、ロールコーター、リバースロールコーター、グラビアコーター、マイクログラビアコーター、ナイフコーター、バーコーター、ワイヤーバーコーター、ダイコーター、ディップコーター、スプレーコーター、アプリケーター等を用いて塗工することができる。 The method for applying the composition for forming the hard coat layer is not particularly limited, and for example, it can be applied using a spin coater, roll coater, reverse roll coater, gravure coater, microgravure coater, knife coater, bar coater, wire bar coater, die coater, dip coater, spray coater, applicator, etc.
　ハードコート層形成用組成物の塗布厚み（塗膜の膜厚）は、１０μｍ以下とすることが好ましく、８μｍ以下とすることがより好ましい。ハードコート層形成用組成物の塗布厚みが１０μｍを超える場合、塗膜の硬化時の収縮によりカールが生じやすくなるため好ましくない。 The coating thickness of the composition for forming a hard coat layer (film thickness) is preferably 10 μm or less, and more preferably 8 μm or less. If the coating thickness of the composition for forming a hard coat layer exceeds 10 μm, curling is likely to occur due to shrinkage during curing, which is not preferred.
　また、保護フィルムＡ（ハードコートフィルム）の鉛筆硬度は３Ｈ以上であることが好ましい。保護フィルムＡの鉛筆硬度が３Ｈ以上である場合、偏光板の表面硬度に優れ、耐久性が向上する。 In addition, it is preferable that the pencil hardness of protective film A (hard coat film) is 3H or more. When protective film A has a pencil hardness of 3H or more, the polarizing plate has excellent surface hardness and improved durability.
　保護フィルムＢは、シクロオレフィンポリマー（ＣＯＰ）、ポリエチレンテレフタレート（ＰＥＴ）及びポリメチルメタクリレート（ＰＭＭＡ）のいずれかからなるフィルム低透湿性のフィルムである。保護フィルムＢは、例えば、紫外線硬化性の接着剤を介して偏光子１に貼り合わされる。保護フィルムＢの厚みは、特に限定されないが、１０～１００μｍであることが好ましい。 Protective film B is a low moisture permeable film made of any one of cycloolefin polymer (COP), polyethylene terephthalate (PET), and polymethyl methacrylate (PMMA). Protective film B is attached to polarizer 1 via, for example, an ultraviolet-curable adhesive. The thickness of protective film B is not particularly limited, but is preferably 10 to 100 μm.
　尚、表示装置において、保護フィルムＢが表示パネル側に配置され、保護フィルムＡのハードコート層３が視認側（表示パネルとは反対側）に配置される。 In addition, in the display device, protective film B is disposed on the display panel side, and hard coat layer 3 of protective film A is disposed on the viewing side (the side opposite the display panel).
　保護フィルムＡの透明基材２は、接着剤として水糊（ＰＶＡ水溶液）を用いて偏光子１のＰＶＡフィルムに貼り合わされる。尚、透明基材２とＰＶＡフィルムとの密着性を確保するため、貼り合わせの前に保護フィルムＡに鹸化処理が施される。保護フィルムＡの偏光子１への貼り合わせに水糊を用いるため、乾燥工程を経た後においても、接着剤層中及びＴＡＣフィルム中には水分が含まれ得る。保護フィルムＡ及びＢの両方を透湿度の低いフィルムを用いて構成した場合、外部からの水分の侵入は抑制されるものの、夏場の車内等の極めて高温な環境下において、接着剤及び／または透明基材２に含まれていた水分が偏光板１０内に留まり続けるため、偏光子１の劣化を引き起こす。 The transparent substrate 2 of the protective film A is bonded to the PVA film of the polarizer 1 using a water-based adhesive (aqueous PVA solution). To ensure adhesion between the transparent substrate 2 and the PVA film, the protective film A is subjected to a saponification treatment before bonding. Because water-based adhesive is used to bond the protective film A to the polarizer 1, moisture may be present in the adhesive layer and the TAC film even after a drying process. If both protective films A and B are made of films with low moisture permeability, the intrusion of moisture from the outside is suppressed, but in extremely high-temperature environments such as the inside of a car in summer, moisture contained in the adhesive and/or transparent substrate 2 will remain in the polarizer 10, causing deterioration of the polarizer 1.
　そこで、本実施形態に係る偏光板１０においては、保護フィルムＡの透湿度と保護フィルムＢの透湿度とに差を設け、かつ、保護フィルムＡ及び保護フィルムＢの透湿度をそれぞれ特定の範囲とすることによって、接着剤及び／またはＴＡＣフィルム由来の水分による偏光子１の劣化を抑制する。 In the polarizing plate 10 according to this embodiment, a difference is provided between the moisture permeability of protective film A and that of protective film B, and the moisture permeability of protective film A and protective film B are each set to a specific range, thereby suppressing deterioration of the polarizer 1 due to moisture from the adhesive and/or TAC film.
　具体的に、４０℃９０％ＲＨにおける保護フィルムＡ及びＢの透湿度をそれぞれＴＡ及びＴＢとすると、ＴＡ及びＴＢは以下の条件（１）及び（２）を同時に満足する。尚、透湿度ＴＡ及びＴＢはいずれも、ＪＩＳ　Ｚ　０２０８：１９７６に規定される、防湿包装材料の透湿度試験法（カップ法）に準拠して測定した値である。
　　２４０ｇ／ｍ２／ｄａｙ＞ＴＡ＞７０ｇ／ｍ２／ｄａｙ　・・・（１）
　　７０ｇ／ｍ２／ｄａｙ≧ＴＢ　・・・（２） Specifically, when the moisture permeabilities of protective films A and B at 40° C. and 90% RH are TA and TB, respectively, TA and TB simultaneously satisfy the following conditions (1) and (2). Note that both of the moisture permeabilities TA and TB are values measured in accordance with the moisture permeability test method (cup method) for moisture-proof packaging materials specified in JIS Z 0208:1976.
240 g/m 2 /day>TA>70 g/m 2 /day ... (1)
70 g/m 2 /day≧TB (2)
　本実施形態に係る偏光板１０は、上記の条件（１）及び（２）を同時に満足することにより、外部から偏光板内部への水分の侵入を抑制しつつ、例えば、８５℃の高温環境下に晒された場合に、保護フィルムＡと偏光子１との貼り合わせに用いた接着剤及び／または保護フィルムＡの透明基材２から発生した水分を外部に排出させることができる。 The polarizing plate 10 according to this embodiment simultaneously satisfies the above conditions (1) and (2), and thus is able to suppress the intrusion of moisture from the outside into the polarizing plate, while at the same time allowing moisture generated from the adhesive used to bond the protective film A and the polarizer 1 and/or the transparent substrate 2 of the protective film A to be discharged to the outside when exposed to a high-temperature environment, for example, at 85°C.
　また、ハードコート層３において、ＡＴＲ法でゲルマニウムプリズムを用いて測定した１７８２～１６８３ｃｍ－１のピーク強度（ピーク高さ）をＰ１、１４２７～１３７４ｃｍ－１のピーク強度をＰ２としたとき、Ｐ２／Ｐ１を硬化度と定義する。１７８２～１６８３ｃｍ－１のピークは、（メタ）アクリレート化合物の（メタ）アクリロイル基を構成するＣ＝Ｏ結合の伸縮振動のピークに相当し、１４２７～１３７４ｃｍ－１強度は、（メタ）アクリレート化合物の（メタ）アクリロイル基のＣ＝Ｃ結合の伸縮振動のピークに相当する。ハードコート層３の硬化度Ｐ２／Ｐ１の値が小さくなると鉛筆硬度が上昇し、硬化度Ｐ２／Ｐ１が大きくなると鉛筆硬度が低下する。また、硬化度Ｐ２／Ｐ１の値が小さくなると透湿度が低下し、硬化度Ｐ２／Ｐ１の値が大きくなると透湿度が上昇する傾向がある。そのため、鉛筆硬度と透湿度とを両立可能な硬化度Ｐ２／Ｐ１の範囲が存在し、具体的には、硬化度Ｐ２／Ｐ１は以下の条件（３）を満足することが好ましい。
　　０．０６０≦Ｐ２／Ｐ１≦０．１５０　・・・（３） In addition, in the hard coat layer 3, when the peak intensity (peak height) at 1782 to 1683 cm −1 measured by the ATR method using a germanium prism is defined as P1, and the peak intensity at 1427 to 1374 cm −1 is defined as P2, and P2/P1 is defined as the degree of cure. The peak at 1782 to 1683 cm −1 corresponds to the peak of the stretching vibration of the C=O bond constituting the (meth)acryloyl group of the (meth)acrylate compound, and the intensity at 1427 to 1374 cm −1 corresponds to the peak of the stretching vibration of the C=C bond of the (meth)acryloyl group of the (meth)acrylate compound. When the value of the degree of cure P2/P1 of the hard coat layer 3 becomes small, the pencil hardness increases, and when the degree of cure P2/P1 becomes large, the pencil hardness decreases. Also, when the value of the degree of cure P2/P1 becomes small, the moisture permeability decreases, and when the value of the degree of cure P2/P1 becomes large, the moisture permeability tends to increase. Therefore, there exists a range of the degree of curing P2/P1 that can achieve both pencil hardness and moisture permeability, and specifically, it is preferable that the degree of curing P2/P1 satisfies the following condition (3).
0.060≦P2/P1≦0.150 (3)
　硬化度Ｐ２／Ｐ１が０．０６０未満になると、保護フィルムＡの透湿度が低くなりすぎることで上記条件（１）を満たすことができなくなる場合があり、この場合、保護フィルムＡの透明基材２から発生した水分を外部に排出させることができなくなる。硬化度Ｐ２／Ｐ１が０．１５０を超えると、保護フィルムＡの鉛筆硬度が悪化する。また、透湿度が高くなりなりすぎることで上記条件（１）を満たすことができなくなる場合があり、この場合、外部から偏光板内部への水分の侵入を抑制することが困難となる。なお、上記条件（１）は、２３９．７ｇ／ｍ２／ｄａｙ≧ＴＡ≧９３．５ｇ／ｍ２／ｄａｙであることが更に好ましく、２１２ｇ／ｍ２／ｄａｙ≧ＴＡ≧１５２．９ｇ／ｍ２／ｄａｙであることが更に好ましく、１９１．７ｇ／ｍ２／ｄａｙ≧ＴＡ≧１５２．９ｇ／ｍ２／ｄａｙであることが更に好ましい。また、条件（３）は、０．０６７≦Ｐ２／Ｐ１≦０．１４９であることが更に好ましく、０．１０１≦Ｐ２／Ｐ１≦０．１３７であることが更に好ましく、０．１０１≦Ｐ２／Ｐ１≦０．１２６であることが更に好ましい。 When the degree of curing P2/P1 is less than 0.060, the moisture permeability of the protective film A becomes too low, and the above condition (1) may not be satisfied. In this case, the moisture generated from the transparent substrate 2 of the protective film A cannot be discharged to the outside. When the degree of curing P2/P1 exceeds 0.150, the pencil hardness of the protective film A deteriorates. In addition, the moisture permeability becomes too high, and the above condition (1) may not be satisfied. In this case, it is difficult to suppress the intrusion of moisture from the outside into the polarizing plate. In addition, the above condition (1) is more preferably 239.7 g/m 2 / day ≧ TA ≧ 93.5 g/m 2 /day, more preferably 212 g/m 2 /day ≧ TA ≧ 152.9 g/ m 2 /day, and more preferably 191.7 g/m 2 /day ≧ TA ≧ 152.9 g/ m 2 /day. Moreover, the condition (3) is more preferably 0.067≦P2/P1≦0.149, more preferably 0.101≦P2/P1≦0.137, and even more preferably 0.101≦P2/P1≦0.126.
　以上説明したように、本実施形態に係る偏光板１０は、上記条件（１）～（３）を満足する保護フィルムＡ及び保護フィルムＢを備える。この構成により、表示パネル側に配置される保護フィルムＢは水分の出入りをほぼ遮断する。一方、視認側に配置される保護フィルムＡは、外部から偏光板１０内部への水分の侵入を抑制しつつ、極めて高温な環境下において、偏光板１０内部で発生した水分の放出を可能とする。したがって、本実施形態に係る偏光板１０においては、高温環境下で用いられた場合に、偏光板１０の内部で発生した水分が留まらないため、偏光子の劣化を抑制し、より長期に渡って偏光板１０の光学性能を維持することが可能となる。 As described above, the polarizing plate 10 according to this embodiment includes protective film A and protective film B that satisfy the above conditions (1) to (3). With this configuration, protective film B arranged on the display panel side almost completely blocks the ingress and egress of moisture. Meanwhile, protective film A arranged on the viewing side allows the release of moisture generated inside the polarizing plate 10 in an extremely high-temperature environment while suppressing the ingress of moisture into the polarizing plate 10 from the outside. Therefore, in the polarizing plate 10 according to this embodiment, when used in a high-temperature environment, moisture generated inside the polarizing plate 10 does not remain, suppressing deterioration of the polarizer and making it possible to maintain the optical performance of the polarizing plate 10 for a longer period of time.
　また、保護フィルムＡのハードコート層３の硬化度が上記条件（３）を満足することにより、保護フィルムＡの透湿度を好ましい範囲内に制御しつつ、高い鉛筆硬度を付与することができる。この結果、保護フィルムＡの低透湿性と表面硬度を長期間に渡って維持することができ、偏光板の耐久性を向上することが可能となる。 In addition, by satisfying the above condition (3) for the degree of curing of the hard coat layer 3 of the protective film A, it is possible to impart high pencil hardness while controlling the moisture permeability of the protective film A within a preferred range. As a result, the low moisture permeability and surface hardness of the protective film A can be maintained for a long period of time, and the durability of the polarizing plate can be improved.
　したがって、本実施形態によれば、高温高湿環境における耐久性に優れた偏光板１０を提供できる。 Therefore, this embodiment can provide a polarizing plate 10 that has excellent durability in high-temperature and high-humidity environments.
　本実施形態に係る偏光板１０は、液晶パネルや有機ＥＬパネル等の画像表示パネルと組み合わせて画像表示装置を構成するのに利用することができる。画像表示装置は、タッチパネルを備えても良い。本実施形態に係る偏光板１０は、高温高湿環境における優れた耐久性を有するので、極めて高温かつ多湿となる車内等の環境に搭載される画像表示装置として好適に利用できる。 The polarizing plate 10 according to this embodiment can be used in combination with an image display panel such as a liquid crystal panel or an organic EL panel to form an image display device. The image display device may also include a touch panel. The polarizing plate 10 according to this embodiment has excellent durability in high temperature and high humidity environments, and can therefore be suitably used as an image display device to be installed in environments such as the inside of a vehicle, which can be extremely hot and humid.
　以下、本発明を具体的に実施した実施例を説明する。 The following describes specific examples of the present invention.
　主材料（重合性材料）、疎水性材料、光重合開始剤及び溶剤を表１に示す割合で含有するハードコート層形成用組成物を調製した。尚、表１に示すＩｒｇａｃｕｒｅ（登録商標）　１８４は、１－ヒドロキシシクロヘキシルフェニルケトンである。 A composition for forming a hard coat layer was prepared containing the main material (polymerizable material), hydrophobic material, photopolymerization initiator, and solvent in the ratios shown in Table 1. Note that Irgacure (registered trademark) 184 shown in Table 1 is 1-hydroxycyclohexyl phenyl ketone.
　調製したハードコート層形成用組成物を厚み４０μｍのＴＡＣフィルム（商品名：ＴＪ４０　富士フイルム社製）に、ワイヤーバーコーターを用いて、表２に記載の塗布厚となるように塗布した。６０℃のオーブン内で１分間加熱して塗膜を乾燥させた後、ＵＶ硬化装置において窒素雰囲気下（酸素濃度５００ｐｐｍ以下）で紫外線を照射して塗膜を硬化させ、実施例１～６及び比較例１～７に係る保護フィルムＡ（ハードコートフィルム）を作製した。比較例６及び７では、保護フィルムＡとして、厚み６０μｍのポリメチルメタクリレート（ＰＭＭＡ）フィルム及び厚み２６μｍのシクロオレフィンポリマー（ＣＯＰ）フィルムを使用した。また、厚み２６μｍのＣＯＰフィルムを保護フィルムＢとした。 The prepared composition for forming a hard coat layer was applied to a 40 μm-thick TAC film (product name: TJ40, manufactured by Fujifilm Corporation) using a wire bar coater to the coating thickness shown in Table 2. The coating was dried by heating in an oven at 60°C for 1 minute, and then cured by irradiating ultraviolet light in a nitrogen atmosphere (oxygen concentration 500 ppm or less) in a UV curing device to produce protective film A (hard coat film) according to Examples 1 to 6 and Comparative Examples 1 to 7. In Comparative Examples 6 and 7, a 60 μm-thick polymethyl methacrylate (PMMA) film and a 26 μm-thick cycloolefin polymer (COP) film were used as protective film A. A 26 μm-thick COP film was used as protective film B.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
　保護フィルムＡのＴＡＣフィルム面と偏光子とを水糊を用いて貼り合わせて乾燥させた後、紫外線硬化性接着剤を用いて偏光子に保護フィルムＢを貼り合わせ、紫外線を照射することにより紫外線硬化性接着剤を硬化させ、偏光板を得た。なお、比較例５においては、保護フィルムＢとして保護フィルムＡを用いた。 The TAC film surface of protective film A was attached to the polarizer using water-based glue and dried, after which protective film B was attached to the polarizer using a UV-curable adhesive, and the UV-curable adhesive was cured by irradiating it with UV light to obtain a polarizing plate. In Comparative Example 5, protective film A was used as protective film B.
　（透湿度）
　偏光子に貼り合わせる前の保護フィルムＡの透湿度ＴＡ及び保護フィルムＢの透湿度ＴＢを、ＪＩＳ　Ｚ　０２０８：１９７６に規定される、防湿包装材料の透湿度試験法（カップ法）に準拠して、４０℃、９０ＲＨ％の条件で測定した。 (Moisture permeability)
The moisture permeability TA of protective film A and the moisture permeability TB of protective film B before being attached to the polarizer were measured under conditions of 40° C. and 90 RH % in accordance with the moisture permeability test method for moisture-proof packaging materials (cup method) specified in JIS Z 0208:1976.
　（硬化度）
　保護フィルムＡのハードコート層に対して、ＡＴＲ法によってＦＴ－ＩＲ分析を行った。ＦＴ－ＩＲ測定結果から１７８２～１６８３ｃｍ－１のピーク高さＰ１、１４２７～１３７４ｃｍ－１のピーク高さＰ２を求め、硬化度Ｐ２／Ｐ１を求めた。このとき、赤外線分光装置としては日本分光株式会社製　ＦＴ／ＩＲ－６１０を用い、プリズムとしてはゲルマニウムプリズムを用いた。 (Degree of hardening)
The hard coat layer of the protective film A was subjected to FT-IR analysis by the ATR method. From the FT-IR measurement results, the peak height P1 at 1782 to 1683 cm -1 and the peak height P2 at 1427 to 1374 cm -1 were obtained, and the degree of cure P2/P1 was calculated. At this time, an FT/IR-610 manufactured by JASCO Corporation was used as the infrared spectrometer, and a germanium prism was used as the prism.
　（鉛筆硬度）
　鉛筆（三菱鉛筆株式会社製　ｕｎｉ、３Ｈ）及びクレメンス型引っ掻き試験機（ＨＡ－３０１、テスター産業株式会社製）を用いて、荷重５００ｇ、引っ掻き速度０．５ｍｍ／ｓｅｃの条件で、保護フィルムＡのハードコート層表面の引っ掻き試験を行った。５枚のサンプルで引っ掻き試験を行い、ハードコート層表面に傷が認められたサンプルが２枚以上あった場合をＮＧ、それ以外をＯＫと評価した。 (Pencil hardness)
A scratch test was performed on the hard coat layer surface of the protective film A using a pencil (uni, 3H, manufactured by Mitsubishi Pencil Co., Ltd.) and a Clemens scratch tester (HA-301, manufactured by Tester Sangyo Co., Ltd.) under conditions of a load of 500 g and a scratch speed of 0.5 mm/sec. The scratch test was performed on five samples, and samples in which scratches were found on the hard coat layer surface of two or more samples were evaluated as NG, and the rest were evaluated as OK.
　（高温高湿耐久試験後の偏光板の偏光度）
　各実施例及び各比較例に係る偏光板を８５℃、８５％ＲＨの恒温槽に投入し、投入から２４０時間後及び５００時間後の偏光度を測定した。尚、偏光度は、積分球付き吸光光度計（Ｖ７１００、日本分光社製）により測定した値に対して、ＪＩＳ　Ｚ　８７０１の２度視野（Ｃ光源）により視感度補正を行うことで算出した。 (Polarization degree of polarizing plate after high temperature and high humidity durability test)
The polarizing plates according to each of the Examples and Comparative Examples were placed in a thermostatic chamber at 85° C. and 85% RH, and the polarization degree was measured 240 hours and 500 hours after the placement. The polarization degree was calculated by performing luminosity correction using a 2-degree visual field (C light source) according to JIS Z 8701 for a value measured using an absorptiometer with an integrating sphere (V7100, manufactured by JASCO Corporation).
　表２に、各実施例及び各比較例に係る保護フィルムＡ及びＢの諸特性と、偏光板の偏光度の測定値（初期値、高温高湿耐久試験前及び後）を示す。 Table 2 shows the characteristics of protective films A and B for each example and comparative example, as well as the measured polarization degree of the polarizing plate (initial value, before and after the high temperature and high humidity durability test).
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
　実施例１～６に係る偏光板は、保護フィルムＡの透湿度ＴＡ及び保護フィルムＢの透湿度ＴＢが上記の条件（１）及び（２）を満足し、更に、保護フィルムＡのハードコート層の硬化度が上記の条件（３）を満足するものである。このため、８５℃８５％ＲＨの恒温槽に５００時間投入された後でも高い偏光度の値を示し、表面硬度も良好であった。 The polarizing plates according to Examples 1 to 6 have a moisture permeability TA of protective film A and a moisture permeability TB of protective film B that satisfy the above conditions (1) and (2), and furthermore, the degree of hardening of the hard coat layer of protective film A satisfies the above condition (3). Therefore, even after being placed in a thermostatic chamber at 85°C and 85% RH for 500 hours, they showed a high degree of polarization and good surface hardness.
　これに対して、比較例１においては、硬化度Ｐ２／Ｐ１が条件（３）の範囲を超え、保護フィルムＡの表面の鉛筆硬度が低下したため、表面硬度も低下した。 In contrast, in Comparative Example 1, the degree of curing P2/P1 exceeded the range of condition (3), and the pencil hardness of the surface of Protective Film A decreased, so the surface hardness also decreased.
　比較例２においては、保護フィルムＡの透湿度ＴＡが条件（１）の範囲を下回り、保護フィルムＡの透湿度ＴＡが低くなった。このため、水分が偏光板内に留まり続け、８５℃、８５％ＲＨの恒温槽に５００時間投入された後の偏光度が実施例と比べて低下した。 In Comparative Example 2, the moisture permeability TA of Protective Film A fell below the range of Condition (1), and the moisture permeability TA of Protective Film A was low. As a result, moisture continued to remain in the polarizing plate, and the degree of polarization after being placed in a thermostatic chamber at 85°C and 85% RH for 500 hours was lower than in the Examples.
　比較例３においては、保護フィルムＡの透湿度ＴＡが条件（１）の範囲を超え、保護フィルムＡの透湿度ＴＡが高くなった。このため、外部からの水分の侵入を十分に抑制できず、８５℃、８５％ＲＨの恒温槽に５００時間投入された後の偏光度が実施例と比べて悪化した。また、硬化度Ｐ２／Ｐ１が条件（３）の範囲を超えていたため、保護フィルムＡの表面の鉛筆硬度が低下し、表面硬度も低下した。 In Comparative Example 3, the moisture permeability TA of protective film A exceeded the range of condition (1), and the moisture permeability TA of protective film A increased. As a result, the intrusion of moisture from the outside could not be sufficiently suppressed, and the polarization degree after being placed in a thermostatic chamber at 85°C and 85% RH for 500 hours deteriorated compared to the Examples. In addition, the degree of curing P2/P1 exceeded the range of condition (3), and therefore the pencil hardness of the surface of protective film A decreased, and the surface hardness also decreased.
　比較例４においては、硬化度Ｐ２／Ｐ１が条件（３）の範囲を下回っていたため、保護フィルムＡの表面の鉛筆硬度は十分であった一方で、保護フィルムＡの透湿度ＴＡが条件（１）の範囲を下回った。このため、水分が偏光板内に留まり続け、８５℃、８５％ＲＨの恒温槽に５００時間投入された後の偏光度が実施例と比べて低下した。 In Comparative Example 4, the degree of curing P2/P1 was below the range of condition (3), so while the pencil hardness of the surface of protective film A was sufficient, the moisture permeability TA of protective film A was below the range of condition (1). As a result, moisture continued to remain in the polarizing plate, and the degree of polarization after being placed in a thermostatic chamber at 85°C and 85% RH for 500 hours was reduced compared to the Examples.
　比較例５においては、保護フィルムＡの透湿度ＴＢが条件（２）の範囲を超え、保護フィルムＢの透湿度ＴＢが高くなった。このため、外部からの水分の侵入を十分に抑制できず、８５℃、８５％ＲＨの恒温槽に５００時間投入された後の偏光度が実施例と比べて低下した。 In Comparative Example 5, the moisture permeability TB of protective film A exceeded the range of condition (2), and the moisture permeability TB of protective film B was high. As a result, the intrusion of moisture from the outside could not be sufficiently suppressed, and the polarization degree after being placed in a thermostatic chamber at 85°C and 85% RH for 500 hours was lower than in the Examples.
　比較例６及び７においては、保護フィルムＡとして極めて透湿度ＴＡが低いＰＭＭＡフィルム及びＣＯＰフィルムをそれぞれ使用したが、８５℃、８５％ＲＨの恒温槽に５００時間投入された後の偏光度が悪化した。これは、保護フィルムＡの透湿度ＴＡが低過ぎるために、高温高湿下に晒された場合に、保護フィルムＡ及び／または接着剤（水糊）に含まれていた水分が偏光板内に留まり続け、偏光子の劣化を引き起こしたと考えられる。また、比較例６及び７の保護フィルムＡは、ハードコート層が設けられていないため、実施例と比べて表面硬度が劣っていた。 In Comparative Examples 6 and 7, a PMMA film and a COP film with extremely low moisture permeability TA were used as protective film A, respectively, but the polarization degree deteriorated after being placed in a thermostatic chamber at 85°C and 85% RH for 500 hours. This is thought to be because the moisture permeability TA of protective film A was too low, and when exposed to high temperature and humidity, the moisture contained in protective film A and/or the adhesive (water glue) continued to remain in the polarizing plate, causing deterioration of the polarizer. In addition, protective film A in Comparative Examples 6 and 7 did not have a hard coat layer, so its surface hardness was inferior to that of the Examples.
　本発明は、表示装置に用いる偏光板として利用することができ、特に、車載用途等の高温環境下で用いられる表示装置の偏光板として好適である。 The present invention can be used as a polarizing plate for display devices, and is particularly suitable as a polarizing plate for display devices used in high-temperature environments such as in-vehicle applications.
Ａ　保護フィルムＡ
Ｂ　保護フィルムＢ
１　偏光子
２　透明基材
３　ハードコート層
１０　偏光板 A Protective Film A
B Protective film B
1 Polarizer 2 Transparent substrate 3 Hard coat layer 10 Polarizing plate

Claims (5)

  1. 　偏光子の一方面に保護フィルムＡが貼り合わされ、他方面に保護フィルムＢが貼り合わされた偏光板であって、
    　前記保護フィルムＡが、透明基材の一面にハードコート層が形成されたハードコートフィルムであり、
    　４０℃９０％ＲＨにおける前記保護フィルムＡの透湿度ＴＡ及び前記保護フィルムＢの透湿度ＴＢが以下の条件（１）及び（２）を同時に満足し、
    　ＡＴＲ法でゲルマニウムプリズムを用いて測定した１７８２～１６８３ｃｍ－１のピーク強度をＰ１、１４２７～１３７４ｃｍ－１のピーク強度をＰ２としたとき、以下の条件（３）を満足する、偏光板。
    　　２４０ｇ／ｍ２／ｄａｙ＞ＴＡ＞７０ｇ／ｍ２／ｄａｙ　・・・（１）
    　　７０ｇ／ｍ２／ｄａｙ≧ＴＢ　・・・（２）
    　　０．０６０≦Ｐ２／Ｐ１≦０．１５０　・・・（３）     A polarizing plate in which a protective film A is bonded to one surface of a polarizer and a protective film B is bonded to the other surface of the polarizer,
    The protective film A is a hard coat film having a hard coat layer formed on one surface of a transparent substrate,
    The moisture permeability TA of the protective film A and the moisture permeability TB of the protective film B at 40° C. and 90% RH simultaneously satisfy the following conditions (1) and (2),
    A polarizing plate which satisfies the following condition (3): P1 is a peak intensity at 1782 to 1683 cm −1 measured using a germanium prism by an ATR method, and P2 is a peak intensity at 1427 to 1374 cm −1 :
    240 g/m 2 /day>TA>70 g/m 2 /day ... (1)
    70 g/m 2 /day≧TB (2)
    0.060≦P2/P1≦0.150 (3)
  2. 　前記透明基材がトリアセチルセルロースフィルムである、請求項１に記載の偏光板。 The polarizing plate according to claim 1, wherein the transparent substrate is a triacetyl cellulose film.
  3. 　前記保護フィルムＡの鉛筆硬度が３Ｈ以上である、請求項１に記載の偏光板。 The polarizing plate according to claim 1, wherein the pencil hardness of the protective film A is 3H or more.
  4. 　前記保護フィルムＢが、シクロオレフィンポリマー、ポリエチレンテレフタレート及びポリメチルメタクリレートのいずれか１種からなるフィルムである、請求項１に記載の偏光板。 The polarizing plate according to claim 1, wherein the protective film B is a film made of one of cycloolefin polymer, polyethylene terephthalate, and polymethyl methacrylate.
  5. 　請求項１～４のいずれかに記載の偏光板を備える、表示装置。 A display device comprising a polarizing plate according to any one of claims 1 to 4.
PCT/JP2023/041394 2022-11-28 2023-11-17 Polarizing plate and display device using same WO2024116890A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2022189252A JP2024077265A (en) 2022-11-28 2022-11-28 Polarizing plate and display device using the same
JP2022-189252 2022-11-28

Publications (1)

Publication Number Publication Date
WO2024116890A1 true WO2024116890A1 (en) 2024-06-06

Family

ID=91323607

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2023/041394 WO2024116890A1 (en) 2022-11-28 2023-11-17 Polarizing plate and display device using same

Country Status (2)

Country Link
JP (1) JP2024077265A (en)
WO (1) WO2024116890A1 (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006039472A (en) * 2004-07-30 2006-02-09 Nippon Zeon Co Ltd Polarizing plate and liquid crystal display device
JP2009198666A (en) * 2008-02-20 2009-09-03 Fujifilm Corp Method of manufacturing polarizing plate, polarizing plate, and liquid crystal display using the polarizing plate
JP2011093133A (en) * 2009-10-28 2011-05-12 Toppan Printing Co Ltd Low moisture vapor transmissive hard coat film, polarizing plate, and transmission type liquid crystal display
JP2014206725A (en) * 2013-03-19 2014-10-30 富士フイルム株式会社 Polarizing plate and liquid crystal display device
WO2021182486A1 (en) * 2020-03-10 2021-09-16 株式会社トッパンＴｏｍｏｅｇａｗａオプティカルフィルム Polarizing plate and display device using same

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006039472A (en) * 2004-07-30 2006-02-09 Nippon Zeon Co Ltd Polarizing plate and liquid crystal display device
JP2009198666A (en) * 2008-02-20 2009-09-03 Fujifilm Corp Method of manufacturing polarizing plate, polarizing plate, and liquid crystal display using the polarizing plate
JP2011093133A (en) * 2009-10-28 2011-05-12 Toppan Printing Co Ltd Low moisture vapor transmissive hard coat film, polarizing plate, and transmission type liquid crystal display
JP2014206725A (en) * 2013-03-19 2014-10-30 富士フイルム株式会社 Polarizing plate and liquid crystal display device
WO2021182486A1 (en) * 2020-03-10 2021-09-16 株式会社トッパンＴｏｍｏｅｇａｗａオプティカルフィルム Polarizing plate and display device using same

Also Published As

Publication number Publication date
JP2024077265A (en) 2024-06-07

Similar Documents

Publication Publication Date Title
JP5737573B2 (en) Release film and method for producing resin laminate
JP6577768B2 (en) Hard coat film, polarizing plate, display member and display device using the same
KR20150068907A (en) Layered body
JP6381631B2 (en) Photo-curing coating film, polarizing plate, and display device
KR100659573B1 (en) Method for manufacturing polarizing film
JP2021015168A (en) Hard coat film and flexible display using the same
WO2016024626A1 (en) Protective film, film layered body, and polarizing plate
WO2024116890A1 (en) Polarizing plate and display device using same
KR20140089623A (en) Method of manufacturing hard-coated polarizing plate
WO2024075658A1 (en) Polarizing plate and display device using same
JP2023095953A (en) Easily adhesive film
WO2023243655A1 (en) Polarizing plate and display device using same
JP2016177163A (en) Hard coat film and information display device
JP6348972B2 (en) Photo-curing coating composition, coating film and polarizing plate using the same
JP7140187B2 (en) Active energy ray-curable composition and film using the same
CN108351436B (en) Optical film, image display device, and method for producing optical film
TW202417887A (en) Polarizing plate and display device using the same
JP2004143202A (en) Active energy ray curing composition, method for forming cured film using the same and cured product thereof and antireflection body
JP2020203383A (en) Production method of film and laminate
KR20150109684A (en) Optical film
WO2024090540A1 (en) Antireflection film
JP2013200488A (en) Low refractive index layer formation resin composition and antireflection film
WO2016152644A1 (en) Hard coat film, information display device, and portable electronic terminal
JP2013025310A (en) Anti-glare hard coating film, polarizer having the same, and display device
WO2024090539A1 (en) Antireflection film