WO2022102645A1

WO2022102645A1 - Image display panel

Info

Publication number: WO2022102645A1
Application number: PCT/JP2021/041298
Authority: WO
Inventors: 智弘山下; 佳史 ▲高▼見; 智剛梨木
Original assignee: 日東電工株式会社
Priority date: 2020-11-16
Filing date: 2021-11-10
Publication date: 2022-05-19
Also published as: TW202223457A; JPWO2022102645A1; CN115989434A; KR20230098771A

Abstract

This image display panel comprises, in the stated order with adhesive layers or bonding layers provided therebetween: a first transparent protective film having an antireflective layer; a polarizing film having a polarizing membrane; and an image display cell. The first transparent protective film having the antireflective layer has a moisture permeability of 50 g/(m²⋅24h) or less, and a laminate, formed by bonding the first transparent protective film having the antireflective layer to one surface of the polarizing film via the adhesive layer or the bonding layer and bonding a glass plate to the other surface of the polarizing film via the adhesive layer or the bonding layer. The laminate has a change amount in single body transmittance of 0-3% before and after a heat resistance test performed at 105°C for 500 hours. The image display panel has excellent durability in a high temperature environment and in a wet heat environment.

Description

Image display panel

The present invention relates to an image display panel.

Conventionally, as a polarizing film used in various image display devices such as a liquid crystal display device and an organic EL display device, since it has both high transmittance and high degree of polarization, it has been dyed (such as iodine and dichroic dyes). A polyvinyl alcohol-based film (containing a dichroic substance) is used. The polarizing film is produced by subjecting a polyvinyl alcohol-based film to various treatments such as swelling, dyeing, crosslinking, stretching, etc. in a bath, washing treatment, and then drying. Further, the polarizing film is usually used as a polarizing film (polarizing plate) in which a transparent protective film such as triacetyl cellulose is bonded to one side or both sides thereof using an adhesive.

The polarizing film is used as a laminated polarizing film (optical laminate) by laminating other optical layers as needed, and the polarizing film or the laminated polarizing film (optical laminate) is a liquid crystal cell or an organic. It is used as an image display panel attached to an image display cell such as an EL element (Patent Document 1).

As the above-mentioned laminated polarizing film, for example, a polarizing film with an antireflection layer provided on the visible side surface of an image display device for the purpose of preventing deterioration of image quality due to external light reflection or the like and improving contrast is known. Patent Document 2-3).

Japanese Unexamined Patent Publication No. 2014-102353 Japanese Unexamined Patent Publication No. 2002-189211 Japanese Unexamined Patent Publication No. 2017-227898

Due to the development of automated driving technology in recent years, the display design of in-vehicle image display panels is becoming more deformed and larger. With such changes in display design, there is a demand for means for further improving durability in a high temperature environment or a moist heat environment.

In view of the above circumstances, it is an object of the present invention to provide an image display panel having excellent durability in a high temperature environment and a moist heat environment.

That is, in the present invention, a first transparent protective film having an antireflection layer, a polarizing film having a polarizing film, and an image display cell are provided in this order via an adhesive layer or an adhesive layer. The first transparent protective film having the antireflection layer, which is a panel, has a moisture permeability of 50 g / ( ^m 2.24 h) or less, and has the adhesive layer or the adhesive layer on one side of the polarizing film. A laminated body in which a first transparent protective film having the antireflection layer is bonded to the other surface of the polarizing film, and a glass plate is bonded to the other surface of the polarizing film via the adhesive layer or the adhesive layer. The present invention relates to an image display panel in which the amount of change in the single-unit permeability is 0 to 3% before and after the heat resistance test under the conditions of 105 ° C. and 500 hours.

The details of the action mechanism of the effect in the image display panel of the present invention are unknown, but it is presumed as follows. However, the present invention is not construed as being limited to this mechanism of action.

In the image display panel of the present invention, a first transparent protective film having an antireflection layer, a polarizing film having a polarizing film, and an image display cell are provided in this order via an adhesive layer or an adhesive layer. The first transparent protective film having the antireflection layer has a moisture permeability of 50 g / ( ^m 2.24 h) or less, and the pressure-sensitive adhesive layer or the adhesive layer is interposed on one side of the polarizing film. The laminate in which the first transparent protective film having the antireflection layer is bonded and the glass plate is bonded to the other surface of the polarizing film via the adhesive layer or the adhesive layer is 105 ° C. The amount of change in the single-unit permeability is 0 to 3% before and after the heat resistance test under the condition of 500 hours. Since the glass plate corresponds to an image display cell, the laminated body corresponds to a pseudo image display panel. So far, there is no known laminated body (pseudo-image display panel) in which the amount of change in the simple substance transmittance is 0 to 3% under the above-mentioned heat resistance test conditions. In the present invention, for example, a polarizing film, a polarizing film for attaching to the first transparent protective film having the antireflection layer, an image display cell, a pressure-sensitive adhesive layer, a polarizing film with an adhesive layer, or the like is heated (aged). By the treatment, the water content contained therein can be reduced, and as a result, the polyene formation of the polarizing film in a high temperature environment can be suppressed, so that the specifications of the above heat resistance test can be satisfied. Further, in the present invention, for example, by including a water-soluble radical scavenger in the polarizing film, radicals generated in the polarizing film can be captured even in a high temperature environment and polyene formation can be suppressed. It can meet the specifications of the heat resistance test. Further, in the present invention, the moisture permeability of the first transparent protective film having the antireflection layer is 50 g / ( ^m 2.24 h) or less, so that the moisture from outside the system (visual side) of the image display panel is removed. Since the entry can be prevented, it is possible to prevent the polarizing film from peeling from the image display cell in a humid and thermal environment.

It is a schematic cross-sectional view which shows one form of an image display panel.

FIG. 1 is a schematic cross-sectional view showing a form of an image display panel of the present invention. In the image display panel 100 of FIG. 1, a first transparent protective film 12 having an antireflection layer, a polarizing film 1 having a polarizing film 11, and an image display cell 90 are interposed via an adhesive layer or an

adhesive layer

20 and 30. And are provided in this order. Further, the polarizing film 1 may have at least a polarizing film 11, and the second transparent protective film 13 may be attached to the side of the first transparent protective film 12 having the antireflection layer of the polarizing film 11. A third transparent protective film 14 may be attached to the image display cell 90 side of the polarizing film 11.

The first transparent protective film 12 having the antireflection layer has an antireflection layer 6 provided on the transparent film 81. The antireflection layer is a laminated body of two or more thin films, and FIG. 1 shows an antireflection layer 6 composed of a laminated body of four

thin films

61, 62, 63, 64. Further, a hard coat layer 71 may be provided on the surface of the transparent film 81 on which the antireflection layer is formed.

In the image display panel of the present invention, a first transparent protective film having an antireflection layer, a polarizing film having a polarizing film, and an image display cell are provided in this order via an adhesive layer or an adhesive layer. The first transparent protective film having the antireflection layer in the image display panel has a moisture permeability of 50 g / ( ^m 2.24 h) or less, and the adhesive layer or the adhesive is attached to one side of the polarizing film. A first transparent protective film having the antireflection layer was bonded via the agent layer, and a glass plate was bonded to the other surface of the polarizing film via the pressure-sensitive adhesive layer or the adhesive layer. The amount of change in the single permeability of the laminated body is 0 to 3% before and after the heat resistance test under the conditions of 105 ° C. and 500 hours.

<First transparent protective film with antireflection layer>
In the first transparent protective film having the antireflection layer of the present invention, an antireflection layer composed of two or more thin films is provided on the transparent film. Generally, in the antireflection layer, the optical film thickness (product of refractive index and thickness) of the thin film is adjusted so that the inverted phases of the incident light and the reflected light cancel each other out. By forming the antireflection layer as a multi-layered laminate of two or more thin films having different refractive indexes, the reflectance can be reduced in a wide wavelength range of visible light.

Examples of the thin film material constituting the antireflection layer include metal oxides, nitrides, and fluorides. Examples of the low refractive index material having a refractive index of 1.6 or less at a wavelength of 550 nm include silicon oxide and magnesium fluoride. Examples of the highly refracting material having a refractive index of 1.9 or more at a wavelength of 550 nm include titanium oxide, niobium oxide, zirconium oxide, tin-doped indium oxide (ITO), and antimony-doped tin oxide (ATO). In addition to the low refractive index layer and the high refractive index layer, as a medium refractive index layer having a refractive index of about 1.50 to 1.85, for example, a thin film made of titanium oxide or a mixture of the low refractive index material and the high refractive index material. May be formed. As the thin film constituting the antireflection layer, it is preferable that the light absorption of visible light is small, and a material having an extinction coefficient of 0.5 or less at a wavelength of 550 nm is preferably used.

The laminated structure of the antireflection layer is, for example, a two-layer structure consisting of a high refractive index layer having an optical film thickness of about 240 nm to 260 nm and a low refractive index layer having an optical film thickness of about 120 nm to 140 nm from the transparent film side; A three-layer structure consisting of a medium refractive index layer having a film thickness of 170 nm to 180 nm, a high refractive index layer having an optical film thickness of 60 nm to 70 nm, and a low refractive index layer having an optical film thickness of 135 nm to 145 nm; an optical film thickness of 20 nm to A high refractive index layer having an optical thickness of about 55 nm, a low refractive index layer having an optical film thickness of about 15 nm to 70 nm, a high refractive index layer having an optical film thickness of about 60 nm to 330 nm, and a low refractive index layer having an optical film thickness of about 100 nm to 160 nm. A low refractive index layer having an optical thickness of about 15 nm to 30 nm, a high refractive index layer having an optical film thickness of about 20 nm to 40 nm, a low refractive index layer having an optical film thickness of about 20 nm to 40 nm, and an optical film thickness. Examples thereof include a five-layer structure consisting of a high refractive index layer having an optical thickness of about 240 nm to 290 nm and a low refractive index layer having an optical film thickness of about 100 nm to 200 nm. The range of the refractive index and the film thickness of the thin film constituting the antireflection layer is not limited to the above examples. Further, the antireflection layer may be a laminated body of six or more thin films.

The antireflection layer is preferably an alternating laminate of a low refractive index layer and a high refractive index layer. In order to reduce reflection at the air interface, the thin film (for example, thin film 64) provided as the outermost surface layer (the surface opposite to the transparent film) of the antireflection layer is preferably a low refractive index layer. As the material of the low refractive index layer and the high refractive index layer, oxides are preferable as described above. Above all, the antireflection layer is preferably an alternating laminate of a silicon oxide (SiO ₂ ) thin film as a low refractive index layer and a niobium (Nb ₂ O ₅ ) thin film as a high refractive index layer.

The transparent film preferably has a visible light transmittance of 80% or more, and more preferably 90% or more. The thickness of the transparent film is not particularly limited, but is preferably about 5 to 300 μm, more preferably 10 to 300 μm, and more preferably 20 to 20 to 300 μm from the viewpoint of workability such as strength and handleability, and thin layer property. It is more preferably 200 μm.

Examples of the resin material constituting the transparent film include a thermoplastic resin having excellent transparency, mechanical strength, and thermal stability. Specific examples of such thermoplastic resins include cellulose-based resins such as triacetyl cellulose, polyester-based resins, polyether sulfone-based resins, polysulfone-based resins, polycarbonate-based resins, polyamide-based resins, polyimide-based resins, and polyolefin-based resins. , (Meta) acrylic resin, cyclic polyolefin resin (norbornen resin), polyarylate resin, polystyrene resin, polyvinyl alcohol resin, and mixtures thereof.

The transparent film contains any suitable additives such as UV absorbers, antioxidants, lubricants, plasticizers, mold release agents, color inhibitors, flame retardants, antistatic agents, pigments, colorants and the like. May be good.

The moisture permeability of the first transparent protective film having the antireflection layer is 50 g / ( ^m 2.24 h) or less. The moisture permeability of the first transparent protective film having the antireflection layer is preferably 30 g / (m 2.24 h) or less, preferably 10 g / ( ^m ^2. 24 h) or less, from the viewpoint of improving durability in a moist heat environment. It is more preferably 24 h) or less, and further preferably ⁵ g / (m 2.24 h) or less. The moisture permeation is the weight of water vapor that permeates a sample having an area of 1 m ² in 24 hours at a relative humidity difference of 40 ° C. and 90%, and is measured according to JIS K7129: 2008 Annex B.

The method for forming the antireflection layer on the transparent film is not particularly limited, and for example, the method described in Japanese Patent Application Laid-Open No. 2017-227898 can be referred to.

It is preferable that a hard coat layer is provided on the antireflection layer side of the transparent film from the viewpoint of improving mechanical properties such as hardness and elastic modulus of the antireflection layer. The hard coat layer preferably has a high surface hardness and excellent scratch resistance, and can be formed by applying a solution containing a curable resin such as a thermosetting resin, an ultraviolet curable resin, or an electron beam curable resin. ..

Examples of the type of the curable resin include various resins such as polyester-based, acrylic-based, urethane-based, acrylic-urethane-based, amide-based, silicone-based, silicate-based, epoxy-based, melamine-based, oxetane-based, and acrylic urethane-based resins. Can be mentioned. Among these, acrylic resins, acrylic urethane resins, and epoxy resins are preferable because they have high hardness, can be cured by ultraviolet rays, and are excellent in productivity. The UV curable resin includes UV curable monomers, oligomers, polymers and the like.

Further, the hard coat layer may have antiglare properties. Examples of the antiglare hard coat layer include those in which fine particles are dispersed in the above-mentioned curable resin. Examples of the fine particles include various metal oxide fine particles such as silica, alumina, titania, zirconia, calcium oxide, tin oxide, indium oxide, cadmium oxide and antimony oxide, glass fine particles, polymethylmethacrylate, polystyrene, polyurethane and acrylic. Cross-linked or uncrosslinked organic fine particles made of various transparent polymers such as styrene copolymer, benzoguanamine, melamine, and polycarbonate, and transparent fine particles such as silicone fine particles can be used without particular limitation. The average particle size of the fine particles is about 1 to 10 μm. The ratio of the fine particles is not particularly limited, but is about 5 to 20 parts by weight with respect to 100 parts by weight of the matrix resin.

The thickness of the hard coat layer is not particularly limited, but is preferably 0.5 μm or more, and more preferably 1 μm or more, from the viewpoint of achieving high hardness. From the viewpoint of ease of formation by coating, the thickness of the hard coat layer is preferably 15 μm or less, and more preferably 10 μm or less.

The surface of the transparent film or the hard coat layer is subjected to surface modification treatment such as corona treatment, plasma treatment, frame treatment, ozone treatment, primer treatment, glow treatment, saponification treatment, and treatment with a coupling agent. May be. Further, a primer layer such as a metal oxide or a nitride may be provided on the surface of the transparent film or the hard coat layer for the purpose of improving the adhesion to the antireflection layer or the like.

<Polarizing film>
In the polarizing film of the present invention, a transparent protective film is bonded to at least one surface of the polarizing film. Here, the transparent protective film bonded to the first transparent protective film side having the antireflection layer of the polarizing film is referred to as a second transparent protective film, and is bonded to the image display cell side of the polarizing film. The transparent protective film is referred to as a third transparent protective film. From the viewpoint of appearance stability during handling work, it is preferable that the polarizing film has a second transparent protective film bonded to the first transparent protective film side having the antireflection layer of the polarizing film. The polarizing film and the transparent protective film are usually bonded to each other via an adhesive layer or an adhesive layer.

<Polarizing film>
The polarizing film has a polarizing film formed by adsorbing and orienting a dichroic substance such as iodine or a dichroic dye on a polyvinyl alcohol-based film. The polarizing film is preferably an iodine-based polarizing film containing iodine as the dichroic substance from the viewpoint of the initial polarization performance of the polarizing film.

The polyvinyl alcohol (PVA) -based film has translucency in the visible light region, and a film that disperses and adsorbs a dichroic substance such as iodine or a dichroic dye can be used without particular limitation. Examples of the material of the polyvinyl alcohol-based film include polyvinyl alcohol or a derivative thereof. Examples of the polyvinyl alcohol derivative include polyvinyl formal, polyvinyl acetal; olefins such as ethylene and propylene; unsaturated carboxylic acids such as acrylic acid, methacrylic acid and crotonic acid, and alkyl esters thereof and those modified with acrylamide and the like. Can be mentioned. The polyvinyl alcohol preferably has an average degree of polymerization of about 100 to 10,000, more preferably about 1,000 to 10,000, and even more preferably about 1,500 to 4,500. .. Further, the polyvinyl alcohol preferably has a saponification degree of about 80 to 100 mol%, more preferably about 95 mol% to 99.95 mol. The average degree of polymerization and the saponification degree can be determined according to JIS K 6726.

The polarizing film preferably contains a water-soluble radical scavenger from the viewpoint of improving durability in a high temperature environment. The water-soluble radical trapping agent is preferably a compound that can dissolve 1 part by weight or more with 100 parts by weight of water at 25 ° C. from the viewpoint of easy transfer to water in the polarizing film, and 100 parts by weight of water at 25 ° C. It is more preferable that the compound is soluble in 2 parts by weight or more, and more preferably 5 parts by weight or more in 100 parts by weight of water at 25 ° C. The water-soluble radical scavenger may be used alone or in combination of two or more.

It is presumed that the water-soluble radical scavenger can suppress polyene formation of the polarizing film in a high temperature environment. Examples of the water-soluble radical scavenger include radical scavengers such as hindered phenol-based, hindered amine-based, phosphorus-based, sulfur-based, benzotriazole-based, benzophenone-based, hydroxylamine-based, sulcylic acid ester-based, and triazine-based compounds. Examples thereof include compounds having a function. The water-soluble radical scavenger is preferably, for example, a nitroxy radical or a compound having a nitroxide group from the viewpoint of radical species generated in the polarizing film.

As the nitroxyl radical or the compound having a nitroxide group, an N-oxyl compound (as a functional group, CN (-C) -O. ^" Is used from the viewpoint of having a radical that is relatively stable in air at room temperature. Examples thereof include compounds having ( ^O. indicates an oxyrad)), and known compounds can be used. Examples of the N-oxyl compound include compounds having an organic group having the following structure.

(In the general formula (1), R ¹ represents an oxy radical, R ² to R ⁵ independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and n represents 0 or 1. (Represented.) In the general formula (1), the left side of the dotted line indicates an arbitrary organic group.

Further, the water-soluble radical scavenger preferably has a molecular weight of 1000 or less, more preferably 500 or less, and more preferably 300 or less, from the viewpoint of efficiently capturing radicals generated in the polarizing film. Is even more preferable.

The content of the water-soluble radical scavenger is 0.005% by weight or more from the viewpoint of improving durability in a high temperature environment when the polarizing film contains the water-soluble radical scavenger. Is more preferable, 0.01% by weight or more is more preferable, 0.1% by weight or more is further preferable, and 20% by weight or less is preferable, and 15% by weight or less is more preferable. It is preferably 10% by weight or less, and more preferably 10% by weight or less.

The polarizing film is obtained by a conventional method for producing a polarizing film, and is obtained, for example, by subjecting the polyvinyl alcohol-based film to an arbitrary swelling step and a washing step, and at least a dyeing step, a cross-linking step, and a stretching step. .. When the polarizing film contains the water-soluble radical scavenger, the treatment bath in any one or more of the swelling step, the washing step, the dyeing step, the cross-linking step, and the stretching step , A water-soluble radical scavenger may be contained.

From the viewpoint of improving the initial degree of polarization of the polarizing film, the thickness of the polarizing film is preferably 1 μm or more, more preferably 2 μm or more, and the moisture content in the polarizing film is reduced to create a high temperature environment. From the viewpoint of suppressing polyene formation underneath, it is preferably 20 μm or less. In particular, in order to obtain a polarizing film having a thickness of about 8 μm or less, a laminate containing a polyvinyl alcohol-based resin layer formed on a thermoplastic resin substrate is used as the polyvinyl alcohol-based film, and the following thin type is used. A method for manufacturing a polarizing film can be applied.

The polarizing film (thin polarizing film) is obtained by a conventional method for manufacturing a polarizing film. For example, a polyvinyl alcohol-based resin containing a polyvinyl alcohol-based resin (PVA-based resin) on one side of a long thermoplastic resin base material. A step of forming a resin layer (PVA-based resin layer) to prepare a laminate, and an arbitrary insolubilization treatment step, a cross-linking treatment step, and cleaning of the laminate while transporting the obtained laminate in the longitudinal direction. It is obtained by performing a treatment step and at least an aerial auxiliary stretching treatment step, a dyeing treatment step, and an underwater stretching treatment step. When the polarizing film contains the water-soluble radical scavenger, one or more of the insolubilization treatment step, the cross-linking treatment step, the cleaning treatment step, the dyeing treatment step, and the underwater stretching treatment step. The treatment bath in the treatment step may contain the water-soluble radical scavenger.

<Transparent protective film>
The transparent protective film is not particularly limited, and various transparent protective films used for the polarizing film can be used. As the material constituting the transparent protective film, for example, a thermoplastic resin having excellent transparency, mechanical strength, thermal stability, moisture barrier property, isotropic property, etc. is used. Examples of the thermoplastic resin include a cell roll ester resin such as triacetyl cell roll, a polyester resin such as polyethylene terephthalate and polyethylene naphthalate, a polyether sulfone resin, a polysulfone resin, a polycarbonate resin, nylon and aroma. Polyamide-based resin such as group polyamide, polyimide-based resin, polyethylene, polypropylene, polyolefin-based resin such as ethylene / propylene copolymer, (meth) acrylic-based resin, cyclo-based or cyclic polyolefin-based resin having norbornene structure (norbornene-based resin) ), Polyallylate-based resin, polystyrene-based resin, polyvinyl alcohol-based resin, and mixtures thereof. Further, as the transparent protective film, a cured layer formed of a thermosetting resin such as (meth) acrylic, urethane, acrylic urethane, epoxy, silicone or the like or an ultraviolet curable resin can be used. Among these, cell roll ester-based resin, polycarbonate-based resin, (meth) acrylic-based resin, cyclic polyolefin-based resin, and polyester-based resin are preferable.

The thickness of the transparent protective film can be appropriately determined, but is generally preferably about 1 to 500 μm, preferably about 1 to 300 μm, from the viewpoint of workability such as strength and handleability, and thin layerability. More preferably, it is more preferably about 5 to 100 μm.

When the transparent protective film is attached to both sides of the polarizing film, the transparent protective films on both sides may be the same or different.

As the transparent protective film, a retardation plate having a front retardation of 40 nm or more and / or a retardation of thickness direction of 80 nm or more can be used. The frontal phase difference is usually controlled in the range of 40 to 200 nm, and the thickness direction phase difference is usually controlled in the range of 80 to 300 nm. When a retardation plate is used as the transparent protective film, the retardation plate also functions as a transparent protective film, so that the thickness can be reduced.

Examples of the retardation plate include a birefringent film formed by uniaxially or biaxially stretching a polymer material, an alignment film of a liquid crystal polymer, and a film in which an alignment layer of a liquid crystal polymer is supported by a film. The thickness of the retardation plate is not particularly limited, but is generally about 20 to 150 μm. The phase plate may be attached to a transparent protective film having no phase difference before use.

The transparent protective film contains any suitable additives such as UV absorbers, antioxidants, lubricants, plasticizers, mold release agents, color inhibitors, flame retardants, antistatic agents, pigments, colorants and the like. You may.

The third transparent protective film preferably has a moisture permeability of 300 g / (m 2.24 h) or less, preferably ²⁰⁰ g / ( ^m 2.24 h) or less, from the viewpoint of production efficiency in the drying step after bonding. Is more preferable. The second transparent protective film has a first transparent protection having an antireflection layer in terms of moisture permeability from the viewpoint of durability of the polarizing film under high temperature and high humidity and production efficiency in the drying process after bonding. It is preferably larger than the moisture permeability of the film, more preferably 100 g / ( ^m 2.24 h) or more, further preferably ²⁰⁰ g / (m 2.24 h) or more, and the moisture permeability is 1000 g / (m 2.24 h) or more. It is preferably (m ^2.24h ) or less, and more preferably 600 g / (m ^2.24h ) or less. The humidity permeability was determined according to the JIS Z0208 moisture permeability test (cup method), and a sample cut to a diameter of 60 mm was set in a moisture permeability cup containing about 15 g of calcium chloride, and the temperature was 40 ° C. and the humidity was 90%. H. It can be calculated by measuring the weight increase of calcium chloride before and after putting it in a constant temperature machine and leaving it for 24 hours.

Other layers such as a hard coat layer, an anti-sticking layer, a diffusion layer, and an anti-glare layer can be provided on the surface of the transparent protective film to which the polarizing film is not bonded. The other layers may be provided on the protective film itself, or may be provided separately from the protective film.

<Adhesive layer>
As the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer, various pressure-sensitive adhesives used for polarizing films can be applied, for example, rubber-based pressure-sensitive adhesives, acrylic-based pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, and vinyl. Examples thereof include an alkyl ether-based adhesive, a polyvinyl alcohol-based adhesive, a polyvinyl porolidone-based adhesive, a polyacrylamide-based adhesive, and a cellulose-based adhesive. Among these, acrylic adhesives are preferable. The acrylic pressure-sensitive adhesive contains an acrylic polymer as a base polymer, and examples thereof include the acrylic pressure-sensitive adhesive described in JP-A-2017-75998.

The acrylic polymer in the acrylic pressure-sensitive adhesive has a monomer unit of (meth) acrylic acid alkyl ester as a main skeleton. As the (meth) acrylic acid alkyl ester, a (meth) acrylic acid alkyl ester having an alkyl group having 1 to 20 carbon atoms is preferably used, and the content of the (meth) acrylic acid alkyl ester is the base polymer. It is preferably 40% by weight or more, more preferably 60% by weight or more, based on the total amount of the constituent monomer components. Further, from the viewpoint of adjusting the adhesiveness of the pressure-sensitive adhesive, a monomer unit such as a nitrogen-containing monomer unit or a hydroxy group-containing monomer may be contained. Further, a cross-linking agent may be used to form a cross-linked structure in the pressure-sensitive adhesive layer. Commonly used substances such as a cross-linking agent and a metal chelate-based cross-linking agent can be used. The amount of the cross-linking agent used is usually 10 parts by weight or less, preferably 5 parts by weight or less, based on 100 parts by weight of the base polymer.

From the viewpoint of adjusting the adhesive strength, the pressure-sensitive adhesive includes a silane coupling agent; a terpene-based pressure-sensitive adhesive, a styrene-based pressure-sensitive adhesive, a phenol-based pressure-sensitive adhesive, a rosin-based pressure-sensitive adhesive, an epoxy-based pressure-sensitive adhesive, and the like. A tackifier may be added. Further, from the viewpoint of improving the light resistance, an ultraviolet absorber may be added. In addition to the above-exemplified components, the pressure-sensitive adhesives include additives such as plasticizers, softeners, deterioration inhibitors, fillers, colorants, antioxidants, surfactants, and antistatic agents, and the characteristics of the pressure-sensitive adhesives. Can be used as long as it does not impair.

As a method for forming the pressure-sensitive adhesive layer, for example, a method in which the pressure-sensitive adhesive is applied to a separator or the like that has been peeled off and dried to form a pressure-sensitive adhesive layer and then transferred to a polarizing film or the like, or the pressure-sensitive adhesive is polarized. Examples thereof include a method of applying to a film or the like and drying to form an adhesive layer. The thickness of the pressure-sensitive adhesive layer is not particularly limited, and is preferably about 1 to 100 μm, preferably about 2 to 50 μm.

<Adhesive layer>
As the adhesive forming the adhesive layer, various adhesives used for polarizing films can be applied, and for example, isocyanate-based adhesives, polyvinyl alcohol-based adhesives, gelatin-based adhesives, vinyl-based latex-based adhesives, and the like. Examples include water-based polyester. These adhesives are usually used as an adhesive consisting of an aqueous solution (water-based adhesive) and contain 0.5 to 60% by weight of a solid content. Among these, a polyvinyl alcohol-based adhesive is preferable, and an acetacetyl group-containing polyvinyl alcohol-based adhesive is more preferable.

The water-based adhesive may contain a cross-linking agent. As the cross-linking agent, a compound having at least two functional groups in one molecule having reactivity with a component such as a polymer constituting the adhesive is usually used, and for example, alkylenediamines; isocyanates; epoxys; Aldehydes; Examples thereof include amino-formaldehydes such as methylol urea and methylol melamine. The blending amount of the cross-linking agent in the adhesive is usually about 10 to 60 parts by weight with respect to 100 parts by weight of the components such as the polymer constituting the adhesive.

In addition to the above, examples of the adhesive include active energy ray-curable adhesives such as ultraviolet curable adhesives and electron beam curable adhesives. Examples of the active energy ray-curable adhesive include (meth) acrylate-based adhesives. Examples of the curable component in the (meth) acrylate-based adhesive include a compound having a (meth) acryloyl group and a compound having a vinyl group. Examples of the compound having a (meth) acryloyl group include alkyl (meth) acrylates having 1 to 20 carbon atoms, such as chain alkyl (meth) acrylates, alicyclic alkyl (meth) acrylates, and polycyclic alkyl (meth) acrylates. ) Acrylate; hydroxyl group-containing (meth) acrylate; epoxy group-containing (meth) acrylate such as glycidyl (meth) acrylate can be mentioned. The (meth) acrylate adhesives are hydroxyethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, (meth) acrylamide, and (meth). It may contain a nitrogen-containing monomer such as acrylamide. The (meth) acrylate-based adhesive has tripropylene glycol diacrylate, 1,9-nonanediol diacrylate, tricyclodecanedimethanol diacrylate, cyclic trimethylolpropane formal acrylate, dioxane glycol diacrylate, and EO as cross-linking components. It may contain a polyfunctional monomer such as modified diglycerin tetraacrylate. Further, a compound having an epoxy group or an oxetanyl group can also be used as the cationic polymerization curable adhesive. The compound having an epoxy group is not particularly limited as long as it has at least two epoxy groups in the molecule, and various generally known curable epoxy compounds can be used.

The adhesive may contain an appropriate additive, if necessary. Examples of the additive include a silane coupling agent, a coupling agent such as a titanium coupling agent, an adhesion promoter such as ethylene oxide, an ultraviolet absorber, a deterioration inhibitor, a dye, a processing aid, an ion trap agent, and an antioxidant. Examples thereof include agents, tackifiers, fillers, plasticizers, leveling agents, foaming inhibitors, antistatic agents, heat-resistant stabilizers, hydrolysis-resistant stabilizers and the like.

The adhesive may be applied to either the transparent protective film side (or the functional layer side described later) or the polarizing film side, which will be described later, or both. After bonding, a drying step is performed to form an adhesive layer composed of a coated dry layer. After the drying step, ultraviolet rays or electron beams can be irradiated as needed. The thickness of the adhesive layer is not particularly limited, and when a water-based adhesive or the like is used, it is preferably about 30 to 5000 nm, more preferably about 100 to 1000 nm, and an ultraviolet curable adhesive. When an electron beam curable adhesive or the like is used, it is preferably about 0.1 to 100 μm, more preferably about 0.5 to 10 μm.

The transparent protective film and the polarizing film may be laminated via an intervening layer such as a surface modification treatment layer, an easy-adhesive layer, a block layer, and a refractive index adjusting layer.

Examples of the surface modification treatment for forming the surface modification layer include corona treatment, plasma treatment, primer treatment, saponification treatment and the like.

Examples of the easy-adhesive for forming the easy-adhesive layer include a forming material containing various resins having a polyester skeleton, a polyether skeleton, a polycarbonate skeleton, a polyurethane skeleton, a silicone-based, a polyamide skeleton, a polyimide skeleton, a polyvinyl alcohol skeleton, and the like. Can be mentioned. The easy-adhesive layer is usually provided in advance on a protective film, and the easy-adhesive layer side of the protective film and the polarizing film are laminated by the adhesive layer or the adhesive layer.

The block layer is a layer having a function to prevent impurities such as oligomers and ions eluted from the transparent protective film and the like from migrating (penetrating) into the polarizing film. The block layer may be a layer having transparency and capable of preventing impurities eluted from the transparent protective film or the like, and examples of the material forming the block layer include urethane prepolymer-based forming materials and cyanoacrylates. Examples include system-forming materials and epoxy-based forming materials.

The refractive index adjusting layer is a layer provided to suppress a decrease in transmittance due to reflection between layers having different refractive indexes such as the transparent protective film and a polarizing film. Examples of the refractive index adjusting material for forming the refractive index adjusting layer include a forming agent containing various resins and additives having a silica-based, acrylic-based, acrylic-styrene-based, melamine-based, and the like.

Further, the polarizing film may be a laminated polarizing film (optical laminate) in which the polarizing film is bonded to an optical layer. The optical layer is not particularly limited, but for example, a reflecting plate, a semi-transmissive plate, a retardation plate (including a wave plate such as 1/2 or 1/4), a liquid crystal display device such as a viewing angle compensation film, or the like is formed. One or two or more optical layers that may be used in the above can be used. Examples of the polarizing film include a reflective polarizing film or a semi-transmissive polarizing film in which a reflecting plate or a semi-transmissive reflecting plate is further laminated on the polarizing film, and an ellipse formed by further laminating a retardation plate on the polarizing film. Examples thereof include a polarizing film or a circular polarizing film, a wide viewing angle polarizing film in which a viewing angle compensating film is further laminated on the polarizing film, and a polarizing film in which a brightness improving film is further laminated on the polarizing film.

In order to attach an image display cell such as a liquid crystal cell or an organic EL element or a first transparent protective film having the antireflection layer to one surface or both surfaces of the polarizing film, the pressure-sensitive adhesive layer is previously attached. Alternatively, the adhesive layer may be attached.

It is preferable that the pressure-sensitive adhesive layer or the exposed surface of the adhesive layer is temporarily covered with a separator for the purpose of preventing contamination or the like until it is put into practical use. As a result, contamination of the pressure-sensitive adhesive layer or the adhesive layer can be prevented under normal handling conditions. As the separator, for example, an appropriate thin leaf such as a plastic film, a rubber sheet, a paper, a cloth, a non-woven fabric, a net, a foamed sheet or a metal foil, or a laminate thereof can be used, and if necessary, a silicone-based or long-chain alkyl-based separator can be used. Those coated with an appropriate release agent such as fluorine-based or molybdenum sulfide are used.

The thickness between the first transparent protective film having the antireflection layer and the polarizing film is preferably 100 μm or less, more preferably 80 μm or less, from the viewpoint of heat durability.

<Image display panel>
In the image display panel of the present invention, the first transparent protective film having the antireflection layer, the polarizing film, and the image display cell are provided in this order via the adhesive layer or the adhesive layer. ..

<Image display cell>
Examples of the image display cell of the present invention include a liquid crystal cell and an organic EL cell. Examples of the liquid crystal cell include a reflective liquid crystal cell that uses external light, a transmissive liquid crystal cell that uses light from a light source such as a backlight, and semi-transmissive that uses both external light and light from a light source. Any of the semi-reflective liquid crystal cells may be used. When the liquid crystal cell uses light from a light source, the image display device (liquid crystal display device) has a polarizing film arranged on the side opposite to the visual recognition side of the image display cell (liquid crystal cell), and the light source is further arranged. Be placed. It is preferable that the polarizing film on the light source side and the liquid crystal cell are bonded to each other via an appropriate adhesive layer. As the driving method of the liquid crystal cell, for example, any type such as VA mode, IPS mode, TN mode, STN mode and bend orientation (π type) can be used.

As the organic EL cell, for example, a cell in which a transparent electrode, an organic light emitting layer, and a metal electrode are sequentially laminated on a transparent substrate to form a light emitting body (organic electroluminescence light emitting body) is preferably used. The organic light emitting layer is a laminate of various organic thin films, for example, a laminate of a hole injection layer made of a triphenylamine derivative or the like and a light emitting layer made of a fluorescent organic solid such as anthracene, or these. Various layer configurations can be adopted, such as a laminated body of an electron-injected layer composed of a light-emitting layer and a perylene derivative, or a laminated body of a hole-injected layer, a light-emitting layer, and an electron-injected layer.

The outermost surface (outermost surface layer) of the image display cell is usually a plastic substrate or a glass substrate, but from the viewpoint of heat resistance and moisture heat resistance, it is preferable that the outermost surface on the visual recognition side is a glass substrate.

When forming the image display panel, from the viewpoint of suppressing a decrease in the single transmittance of the polarizing film in a high temperature environment, polarization for bonding to a first transparent protective film or an image display cell having an antireflection layer. A film, a pressure-sensitive adhesive layer, a polarizing film with an adhesive layer, or the like may be heated (aged). The heating conditions in the heating (aging) treatment are not particularly limited as long as the moisture contained in the pressure-sensitive adhesive layer or the adhesive layer provided on both sides of the polarizing film and the polarizing film can be sufficiently reduced. For example, the heating temperature is 70. The temperature is preferably about 90 ° C, more preferably about 75 to 85 ° C. The heating time is preferably about 30 minutes to 5 hours, more preferably about 1 hour to 3 hours. Further, when the pressure-sensitive adhesive layer or the adhesive layer is attached to both sides of the polarizing film and the heat (aging) treatment is performed, it is effective that the pressure-sensitive adhesive layer or the adhesive layer has high moisture permeability, while it is effective on one side. When heat (aging) treatment is performed with the pressure-sensitive adhesive layer or the adhesive layer attached to the surface, the water content of the pressure-sensitive adhesive layer or the adhesive layer (the pressure-sensitive adhesive layer or the adhesive layer on the other surface) to be laminated later is The lower one is more effective.

The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples.

<Example 1>
<Preparation of polarizing film>
A polyvinyl alcohol film having an average degree of polymerization of 2,400, a saponification degree of 99.9 mol%, and a thickness of 45 μm was prepared. The polyvinyl alcohol film was immersed in a swelling bath (water bath) at 30 ° C. for 30 seconds between rolls having different peripheral speed ratios and stretched 2.2 times in the transport direction while swelling (swelling step), followed by In a dyeing bath at 30 ° C. (an iodine aqueous solution obtained by mixing iodine and potassium iodide in a weight ratio of 1: 7 with respect to 100 parts by weight of water) so that the polarizing film has a predetermined permeability. While adjusting the iodine concentration, it was immersed for 30 seconds and dyed while being stretched 3.3 times in the transport direction based on the original polyvinyl alcohol film (polyvinyl alcohol film that was not stretched at all in the transport direction) (dyeing step). .. Next, the dyed polyvinyl alcohol film is placed in a cross-linked bath at 40 ° C. (an aqueous solution having a boric acid concentration of 3.5% by weight, a potassium iodide concentration of 3.0% by weight, and a zinc sulfate concentration of 3.6% by weight). It was soaked in for 28 seconds and stretched up to 3.6 times in the transport direction with respect to the original polyvinyl alcohol film (crosslinking step). Further, the obtained polyvinyl alcohol film is placed in a stretching bath at 64 ° C. (an aqueous solution having a boric acid concentration of 4.5% by weight, a potassium iodide concentration of 5.0% by weight, and a zinc sulfate concentration of 5.0% by weight). After immersing in for 60 seconds and stretching up to 6.0 times in the transport direction with reference to the original polyvinyl alcohol film (stretching step), a washing bath at 27 ° C. (potassium iodide concentration 2.3% by weight, water solubility). As a radical trapping agent, the compound was immersed in an aqueous solution having a compound concentration of 1.0% by weight represented by the following general formula (2) for 10 seconds (cleaning step). The washed polyvinyl alcohol film was dried at 40 ° C. for 30 seconds to prepare a polarizing film. The content of the compound represented by the following general formula (2) in the polarizing film was 0.3% by weight, and the thickness of the polarizing film was 18 μm.

<Method for measuring the content (% by weight) of the water-soluble radical scavenger in the polarizing film>
Approximately 20 mg of the polarizing film is collected, quantified, heated and dissolved in 1 mL of water, diluted with 4.5 mL of methanol, the obtained extract is filtered through a membrane filter, and the filtrate is HPLC (ACQUITY UPLC manufactured by Waters). The concentration of the water-soluble radical trapping agent was measured using H-class Bio).

<Manufacturing of polarizing film>
As an adhesive, a polyvinyl alcohol resin containing an acetoacetyl group (average degree of polymerization of 1,200, saponification degree of 98.5 mol%, acetoacetylation degree of 5 mol%) and methylol melamine in a weight ratio of 3: The aqueous solution contained in 1 was used. Using this adhesive, a cycloolefin-based transparent protective film having a thickness of 18 μm (manufactured by Nippon Zeon Co., Ltd.) was used as a third transparent protective film on one surface (image display cell side) of the polarizing film obtained above. ZT12, moisture permeability 10 g / ( ^m 2.24 h)), and on the other surface (visual side), as a second transparent protective film, triacetyl cellulose film (manufactured by Fuji Film, trade name "TJ40UL"). A transparent protective film with a thickness of 48 μm (water permeability is 300 g / ( ^m 2.24 h)) on which HC is formed is bonded by a roll bonding machine, and then heat-dried in an oven (temperature is 90 ° C., time is 10). After a minute), a polarizing film was prepared in which a transparent protective film was bonded to both sides of the polarizing film.

<Preparation of acrylic adhesive>
A monomer mixture containing 99 parts of butyl acrylate and 1 part of 4-hydroxybutyl acrylate was placed in a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas introduction tube, and a cooler. Further, with respect to 100 parts of the monomer mixture (solid content), 0.1 part of 2,2'-azobisisobutyronitrile as a polymerization initiator is charged together with 100 parts of ethyl acetate, and nitrogen gas is added while gently stirring. After introduction and substitution with nitrogen, the liquid temperature in the flask was maintained at around 55 ° C. and a polymerization reaction was carried out for 8 hours to prepare a solution of an acrylic polymer having a weight average molecular weight (Mw) of 1.8 million. Then, with respect to 100 parts of the solid content of the obtained acrylic polymer solution, 0.02 part of an isocyanate cross-linking agent (manufactured by Tosoh Corporation, trade name "Takenate D110N", trimethylolpropane / xylylene diisocyanate adduct), silane. A solution of the acrylic pressure-sensitive adhesive composition was prepared by blending 0.2 parts of a coupling agent (manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name "X-41-1056").

<Making a polarizing film with an adhesive layer>
Adhesive after drying of the solution of the acrylic pressure-sensitive adhesive composition obtained above on one side of a polyethylene terephthalate film (manufactured by Mitsubishi Chemical Polyester Film, trade name "MRF38", separator film) treated with a silicone-based release agent. It was applied so that the thickness of the agent layer was 20 μm, and dried at 90 ° C. for 1 minute to form an adhesive layer on the surface of the separator film. Next, the pressure-sensitive adhesive layer formed on the separator film was transferred to the protective film surface on the image display cell side of the polarizing film produced above to prepare a polarizing film with a pressure-sensitive adhesive layer.

<Preparation of a first transparent protective film having an antireflection layer>
After drying 100 parts by weight (solid content) of an ultraviolet curable acrylic resin (manufactured by DIC, trade name "GRANDIC PC-1070") on one side of a cellulose triacetate film (manufactured by Fuji Film, trade name "Fujitac") having a thickness of 40 μm. Was coated to a thickness of 5 μm and dried at 80 ° C. for 3 minutes. Then, using a high-pressure mercury lamp, ultraviolet rays having an integrated light amount of 200 mJ / cm ² were applied to cure the coating layer and form a hard coat layer. The obtained triacetyl cellulose film was obtained. The triacetyl cellulose film on which the hard coat layer was formed was introduced into a roll-to-roll type spatter film forming apparatus, and the hard coat layer forming surface was bombarded while running the film. After performing (plasma treatment with Ar gas), a 3.5 nm silicon oxide layer was formed as a primer layer, and a 12 nm Nb ₂ O ₅ layer, a 28 nm SiO ₂ layer, and a 100 nm Nb ₂ were formed on the film. The O5 layer and the 85 nm SiO ₂ layer were sequentially formed to form a _first transparent protective film (film A) having an antireflection layer. The bombard treatment was carried out at a pressure of 0.5 Pa. As the silicon oxide layer as a layer, a Si target was used, and _spatter film formation was performed under the conditions of a substrate temperature of _-8 ° C., an argon flow rate of 300 sccm, and a pressure of 0.2 Pa. An Nb target was used to form the _O5 _layer , and the film was formed at a substrate temperature of -8 ° _C , an argon flow rate of ₂₀₀ sccm, and a pressure of 0.10 Pa. Adjusted the amount of oxygen introduced so that the film forming mode maintained the transition region by controlling the plasma emission monitoring (PEM). The moisture permeability of the first transparent protective film having the antireflection layer was described above. As per JIS K7129: 2008, it is measured according to Annex B.

<Manufacturing of a first polarizing film with a transparent protective film having an antireflection layer>
The polarizing film with the pressure-sensitive adhesive layer obtained above was allowed to stand in a hot air oven at 80 ° C. for 2 hours for aging treatment, then taken out of the oven and allowed to stand in an environment of 23 ° C. and 55% for 1 hour. Next, the first transparent protective film having the antireflection layer obtained above is transferred to the surface on which the antireflection layer is not formed, and the acrylic pressure-sensitive adhesive layer having a thickness of 20 μm is transferred to the polarizing film with the pressure-sensitive adhesive layer. A polarizing film with a first transparent protective film having an antireflection layer was produced by laminating it on the surface of the transparent protective film on the visual recognition side.

<Making a pseudo image display panel>
The polarizing film with the first transparent protective film having the antireflection layer obtained above is cut into a size of 150 × 45 mm so that the absorption axis of the polarizing film is parallel to the long side, and is passed through the adhesive layer. , A glass plate (EG-XG manufactured by Hiraoka Special Glass Manufacturing Co., Ltd., 165 × 50 mm, thickness 0.7 mm) was laminated and autoclaved at 50 ° C. and 0.5 MPa for 15 minutes to prepare a pseudo image display panel.

<Evaluation of durability in high temperature environment>
The pseudo image display panel obtained above was allowed to stand in a hot air oven at a temperature of 105 ° C. for 500 hours, and the single transmittance (ΔTs) before and after charging (heating) was measured. The single transmittance was measured using a spectrophotometer (LPF-200, manufactured by Otsuka Electronics Co., Ltd.). The simple substance transmittance is a Y value corrected for luminosity factor by a double field of view (C light source) of JlS Z 8701-1982. The measurement wavelength is 380 to 780 nm (every 5 nm).
ΔTs (%) = Ts ₅₀₀ -Ts ₀
Here, Ts ₀ is the initial (before heating) single transmittance, and Ts ₅₀₀ is the single transmittance after 500 hours of heating. ΔTs (%) is preferably 0% or more and 3% or less, and more preferably 0% or more and 2% or less. The results are shown in Table 1.

<Evaluation of durability in a moist heat environment>
Wrap a tex wipe (manufactured by Iris, trade name "TEXWIPE") soaked in water around the pseudo image display panel obtained above, put it in a plastic bag, seal it, and put it in a moist heat oven at 60 ° C and 95% RH. The appearance after standing for 100 hours was visually evaluated according to the following criteria.
〇: No peeling between the polarizing film and the glass plate.
Δ: Slight peeling occurred between the polarizing film and the glass plate.
X: Significant peeling of the polarizing film and the glass plate occurred.

<Example 2>
In the production of the first transparent protective film having an antireflection layer, the argon flow rate in the film formation of the SiO ₂ layer is 400 sccm and the pressure is 0.2 Pa, and the argon flow rate in the film formation of the Nb ₂ O ₅ layer is 1200 sccm and the pressure is 0.4 Pa. A pseudo image display panel was produced by the same method as in Example 1 except that the polarizing film with the first transparent protective film (film B) having the antireflection layer formed under the above conditions was used.

<Example 3>
Example 2 in the production of the first polarizing film with a transparent protective film having an antireflection layer, except that the polarizing film with an adhesive layer was allowed to stand in a hot air oven at 80 ° C. for 2 hours and was not aged. A pseudo image display panel was produced by the same method as in the above.

<Example 4>
A pseudo image display panel was produced by the same method as in Example 2 except that the compound represented by the general formula (2) was not added to the washing bath in the production of the polarizing film.

<Example 5>
In the production of the first transparent protective film having an antireflection layer, the argon flow rate in the film formation of the SiO ₂ layer is 800 sccm and the pressure is 0.3 Pa, and the argon flow rate in the film formation of the Nb ₂ O ₅ layer is 1300 sccm and the pressure is 0.4 Pa. A pseudo image display panel was produced by the same method as in Example 3 except that the polarizing film with the first transparent protective film (film C) having the antireflection layer formed under the above conditions was used.

<Comparative Example 1>
In the production of the first transparent protective film having an antireflection layer, the argon flow rate in the film formation of the SiO ₂ layer is 1100 sccm and the pressure is 0.4 Pa, and the argon flow rate in the film formation of the Nb ₂ O ₅ layer is 1500 sccm and the pressure is 0.5 Pa. A pseudo image display panel was produced by the same method as in Example 3 except that the polarizing film with the first transparent protective film (film D) having the antireflection layer formed under the above conditions was used.

<Comparative Example 2>
In the production of the polarizing film, the compound represented by the general formula (2) was not added to the washing bath, and in the production of the first polarizing film with a transparent protective film having an antireflection layer, the polarizing film with an adhesive layer was 80. A pseudo image display panel was produced by the same method as in Example 1 except that the film was allowed to stand in a hot air oven at ° C for 2 hours without aging treatment.

Using the pseudo image display panels of the examples and comparative examples obtained above, the above <evaluation of durability in a high temperature environment> and <evaluation of peeling in a moist heat environment> were performed. The results are shown in Table 1.

1: Polarizing film with polarizing film 11: Polarizing film 12: First transparent protective film with antireflection layer 13: Second transparent protective film 14: Third transparent protective film 20, 30: Adhesive layer or adhesion Agent layer 81: Transparent film 6:

Antireflection layer

61, 62, 63, 64: Thin film 71: Hard coat layer 90: Image display cell 100: Image display panel

Claims

An image display panel in which a first transparent protective film having an antireflection layer, a polarizing film having a polarizing film, and an image display cell are provided in this order via an adhesive layer or an adhesive layer.
The first transparent protective film having the antireflection layer has a moisture permeability of 50 g / ( m 2.24 h) or less.
A first transparent protective film having the antireflection layer is attached to one side of the polarizing film via the pressure-sensitive adhesive layer or the adhesive layer, and the pressure-sensitive adhesive layer or the pressure-sensitive adhesive layer is attached to the other side of the polarizing film. The laminate in which the glass plates are bonded via the adhesive layer is characterized in that the amount of change in the single transmittance is 0 to 3% before and after the heat resistance test under the conditions of 105 ° C. and 500 hours. Image display panel.
The image display panel according to claim 1, wherein the polarizing film has a thickness of 20 μm or less.
The image display according to claim 1 or 2, wherein the polarizing film has a second transparent protective film bonded to the first transparent protective film side having the antireflection layer of the polarizing film. panel.
The image display panel according to claim 3, wherein the moisture permeability of the second transparent protective film is larger than the moisture permeability of the first transparent protective film having the antireflection layer.
The image display panel according to any one of claims 1 to 4, wherein the thickness between the first transparent protective film having the antireflection layer and the polarizing film is 100 μm or less.
The image display panel according to any one of claims 1 to 5, wherein the polarizing film is a third transparent protective film bonded to the image display cell side of the polarizing film.
The image display panel according to any one of claims 1 to 6, wherein the antireflection layer is a layer composed of two or more thin films having different refractive indexes.
The image display panel according to any one of claims 1 to 7, wherein the first transparent protective film having the antireflection layer includes a hard coat layer and the antireflection layer in this order on the transparent film.
The image display panel according to any one of claims 1 to 8, wherein the image display cell is a glass substrate on the outermost surface on the visual recognition side.