JP7193592B2 - Adhesive composition for organic EL display device, adhesive layer for organic EL display device, polarizing film with adhesive layer for organic EL display device, and organic EL display device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an adhesive composition for organic EL (electroluminescence) display devices (OLED). The present invention also relates to a pressure-sensitive adhesive layer for an organic EL display device formed from the pressure-sensitive adhesive composition for an organic EL display device, and a polarizing film with a pressure-sensitive adhesive layer having the pressure-sensitive adhesive layer. Furthermore, the present invention relates to an organic EL display device using the adhesive layer and/or the polarizing film.

In recent years, organic EL display devices equipped with organic EL panels have come to be widely used in various applications such as mobile phones, car navigation devices, personal computer monitors, and televisions. In order to prevent external light from being reflected by a metal electrode (cathode) and viewed as a mirror surface, an organic EL display device usually has a circularly polarizing plate (polarizing plate and 1 A stack of /4 wave plates, etc.) is arranged. A decorative panel or the like may be further laminated on the circularly polarizing plate laminated on the viewing side surface of the organic EL panel. The constituent members of the organic EL display device, such as the circularly polarizing plate and the decorative panel, are usually laminated via a bonding material such as a pressure-sensitive adhesive layer or an adhesive layer.

In an image display device such as an organic EL display device, the constituent members in the image display device may deteriorate due to incident ultraviolet light. is known to provide Specifically, for example, it has at least one ultraviolet absorbing layer, has a light transmittance of 30% or less at a wavelength of 380 nm, and has a visible light transmittance of 80% or more on the longer wavelength side than the wavelength of 430 nm. Transparent double-sided pressure-sensitive adhesive sheets for image display devices (see, for example, Patent Document 1) and pressure-sensitive adhesive sheets having a pressure-sensitive adhesive layer containing an acrylic polymer and a triazine-based ultraviolet absorber are known (see, for example, Patent Document 2). .

JP 2012-211305 A JP 2013-75978 A

The pressure-sensitive adhesive sheets described in Patent Documents 1 and 2 can control the transmittance of light having a wavelength of 380 nm. was not sufficient. This is because the adhesive sheets described in Patent Documents 1 and 2 can absorb light with a wavelength of 380 nm, but the wavelength region (380 nm 430 nm) is not sufficiently absorbed, and it is thought that the transmitted light causes deterioration.

Therefore, in order to suppress deterioration of the organic EL element, the transmission of light having a wavelength (380 nm to 430 nm) shorter than the light emitting region (longer wavelength side than 430 nm) of the organic EL element is suppressed. It is necessary to use in an organic EL display device a layer that can ensure sufficient transmittance of visible light in the light emitting region and has high transparency.

Therefore, the present invention provides an organic EL display device that can suppress deterioration of the organic EL element and form an adhesive layer for an organic EL display device having high transparency by using it in an organic EL display device. An object of the present invention is to provide a pressure-sensitive adhesive composition for display devices. Further, an adhesive layer for an organic EL display device formed from the adhesive composition, a polarizing film and a polarizing film with an adhesive layer having an adhesive layer for an organic EL display device, the adhesive layer and/or the adhesive An object of the present invention is to provide an organic EL display device including a layered polarizing film.

The inventors of the present invention have made intensive studies to solve the above problems, and as a result, have found the following pressure-sensitive adhesive composition for organic EL display devices, and have completed the present invention.

That is, the present invention relates to a pressure-sensitive adhesive composition for an organic EL display device, comprising a base polymer, an ultraviolet absorber, and a dye compound having a maximum absorption wavelength in an absorption spectrum of 380 to 430 nm. .

The base polymer is preferably a (meth)acrylic polymer.

It is preferable that the maximum absorption wavelength of the absorption spectrum of the ultraviolet absorber is in the wavelength region of 300 to 400 nm.

The present invention also relates to a pressure-sensitive adhesive layer for an organic EL display device, which is formed from the pressure-sensitive adhesive composition for an organic EL display device.

The pressure-sensitive adhesive layer for an organic EL display device has an average transmittance of 5% or less at a wavelength of 300 to 400 nm, an average transmittance of 70% or more at a wavelength of 450 to 500 nm, and an average transmittance of 500 to 780 nm. It is preferably 80% or more.

Furthermore, the average transmittance is 5% or less at a wavelength of 300 to 400 nm, 30% or less at a wavelength of 400 nm to 430 nm, and 70% at a wavelength of 450 to 500 nm. Thus, it is possible to use one having an average transmittance of 80% or more at a wavelength of 500 to 780 nm.

Furthermore, the average transmittance is 5% or less at a wavelength of 300 to 400 nm, more than 30% to 75% at a wavelength of 400 nm to 430 nm, and an average transmittance at a wavelength of 450 to 500 nm. It is possible to use one having a transmittance of 80% or more and an average transmittance of 80% or more at a wavelength of 500 to 780 nm.

The present invention also relates to a polarizing film with an adhesive layer for an organic EL display device, comprising a polarizing film and the adhesive layer for an organic EL display device.

The polarizing film is provided with a transparent protective film on one surface of the polarizer and has a retardation film on the other surface, and the adhesive layer for an organic EL display device is the polarized light of the retardation film. It is preferably provided on the surface opposite to the surface in contact with the element and/or the surface of the transparent protective film opposite to the surface in contact with the polarizer.

The polarizing film with an adhesive layer for an organic EL display device has a first adhesive layer, a transparent protective film, a polarizer, a second adhesive layer, a retardation film, and a third adhesive layer in this order,
At least one pressure-sensitive adhesive layer of the first pressure-sensitive adhesive layer, the second pressure-sensitive adhesive layer, and the third pressure-sensitive adhesive layer is preferably the pressure-sensitive adhesive layer for an organic EL display device.

It is preferable that the retardation film is a quarter wavelength plate and the polarizing film is a circularly polarizing film.

The present invention also relates to an organic EL display device using at least one of the pressure-sensitive adhesive layer for an organic EL display device or the polarizing film with the pressure-sensitive adhesive layer for an organic EL display device.

The pressure-sensitive adhesive composition for an organic EL display device of the present invention can suppress deterioration of an organic EL element by using it in an organic EL display device, and forms a pressure-sensitive adhesive layer for an organic EL display device having high transparency. can do. Therefore, the organic EL display device using the pressure-sensitive adhesive layer for the organic EL display device of the present invention and/or the polarizing film with the pressure-sensitive adhesive layer containing the pressure-sensitive adhesive layer for the organic EL display device has excellent weather deterioration resistance, Life can be extended.

BRIEF DESCRIPTION OF THE DRAWINGS (a) to (c) are cross-sectional views schematically showing one embodiment of a polarizing film with an adhesive layer for an organic EL display device of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically one Embodiment of the organic electroluminescence display of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically one Embodiment of the organic electroluminescence display of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically one Embodiment of the organic electroluminescence display of this invention.

1. Adhesive composition for organic EL display device The adhesive composition for an organic EL display device of the present invention comprises a base polymer, an ultraviolet absorber, and a dye compound having a maximum absorption wavelength in the absorption spectrum of 380 to 430 nm. characterized by comprising Here, the maximum absorption wavelength means the absorption maximum wavelength showing the maximum absorbance among a plurality of absorption maxima in the spectral absorption spectrum in the wavelength region of 300 to 460 nm. .

The base polymer used in the present invention is not particularly limited, and the types of the adhesive composition include, for example, rubber-based adhesives, acrylic-based adhesives, silicone-based adhesives, urethane-based adhesives, vinyl alkyl Ether-based adhesives, polyvinyl alcohol-based adhesives, polyvinylpyrrolidone-based adhesives, polyacrylamide-based adhesives, cellulose-based adhesives, and the like can be mentioned. Among these pressure-sensitive adhesives, acrylic pressure-sensitive adhesives are preferably used because they have excellent optical transparency, exhibit appropriate adhesion, cohesiveness, and adhesive properties, and are excellent in weather resistance and heat resistance. . In the present invention, an acrylic pressure-sensitive adhesive composition containing a (meth)acrylic polymer as a base polymer is preferred.

The acrylic pressure-sensitive adhesive composition includes, for example, a partial polymer of a monomer component containing an alkyl (meth)acrylate and/or a (meth)acrylic polymer obtained from the monomer component, an ultraviolet absorber, and a dye compound. is preferred.

(1) Partially polymerized monomer component and (meth)acrylic polymer The acrylic pressure-sensitive adhesive composition is obtained from a partially polymerized monomer component containing an alkyl (meth)acrylate and/or the monomer component ( Contains meth)acrylic polymers.

Examples of the alkyl (meth)acrylate include those having a linear or branched alkyl group having 1 to 24 carbon atoms at the ester end. Alkyl (meth)acrylate can be used individually by 1 type or in combination of 2 or more types. "Alkyl (meth)acrylate" refers to alkyl acrylate and/or alkyl methacrylate, and has the same meaning as (meth) in the present invention.

Examples of the alkyl (meth)acrylate include the aforementioned linear or branched alkyl (meth)acrylate having 1 to 24 carbon atoms. Among these, alkyl (meth)acrylates having 1 to 9 carbon atoms are preferred, alkyl (meth)acrylates having 4 to 9 carbon atoms are more preferred, and branched alkyl (meth)acrylates having 4 to 9 carbon atoms are even more preferred. . The alkyl (meth)acrylate is preferable in that the adhesive properties are easily balanced. For example, alkyl (meth)acrylates having 4 to 9 carbon atoms specifically include n-butyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, and isobutyl (meth)acrylate. , n-pentyl (meth)acrylate, isopentyl (meth)acrylate, isohexyl (meth)acrylate, isoheptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate and the like. , these can be used individually by 1 type or in combination of 2 or more types.

In the present invention, the alkyl (meth)acrylate having an alkyl group having 1 to 24 carbon atoms at the ester end is 40% by weight or more with respect to the total amount of the monofunctional monomer component forming the (meth)acrylic polymer. is preferred, 50% by weight or more is more preferred, and 60% by weight or more is even more preferred.

The monomer component may contain a copolymerizable monomer other than the alkyl (meth)acrylate as a monofunctional monomer component. A copolymerizable monomer can be used as the remainder of the alkyl (meth)acrylate in the monomer component.

Comonomers can include, for example, cyclic nitrogen-containing monomers. As the cyclic nitrogen-containing monomer, those having a polymerizable functional group having an unsaturated double bond such as a (meth)acryloyl group or a vinyl group and having a cyclic nitrogen structure can be used without particular limitation. The cyclic nitrogen structure preferably has a nitrogen atom within the cyclic structure. Examples of cyclic nitrogen-containing monomers include lactam-based vinyl monomers such as N-vinylpyrrolidone, N-vinyl-ε-caprolactam, and methylvinylpyrrolidone; vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinyl Vinyl-based monomers having a nitrogen-containing heterocyclic ring such as imidazole, vinyloxazole, and vinylmorpholine are included. Also included are (meth)acrylic monomers containing a heterocyclic ring such as a morpholine ring, piperidine ring, pyrrolidine ring and piperazine ring. Specific examples include N-acryloylmorpholine, N-acryloylpiperidine, N-methacryloylpiperidine, N-acryloylpyrrolidine and the like. Among the cyclic nitrogen-containing monomers, lactam vinyl monomers are preferred.

In the present invention, the cyclic nitrogen-containing monomer is preferably 0.5 to 50% by weight, preferably 0.5 to 40% by weight, relative to the total amount of monofunctional monomer components forming the (meth)acrylic polymer. is more preferred, and 0.5 to 30% by weight is even more preferred.

The monomer component used in the present invention can contain a hydroxyl group-containing monomer as a monofunctional monomer component. As the hydroxyl group-containing monomer, those having a polymerizable functional group having an unsaturated double bond such as a (meth)acryloyl group or a vinyl group and having a hydroxyl group can be used without particular limitation. Examples of hydroxyl group-containing monomers include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl ( Hydroxyalkyl (meth)acrylates such as meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate; (4 - hydroxyalkylcycloalkane (meth)acrylates such as hydroxymethylcyclohexyl)methyl (meth)acrylate. Other examples include hydroxyethyl (meth)acrylamide, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether and the like. These can be used alone or in combination. Among these, hydroxyalkyl (meth)acrylates are preferred.

In the present invention, the hydroxyl group-containing monomer is preferably 1% by weight or more with respect to the total amount of monofunctional monomer components forming the (meth)acrylic polymer from the viewpoint of increasing adhesive strength and cohesive strength. Although it is 2% by weight or more, it is more preferably 3% by weight or more. On the other hand, if the amount of the hydroxyl group-containing monomer is too large, the pressure-sensitive adhesive layer may become hard and the adhesive strength may decrease, and the viscosity of the pressure-sensitive adhesive may become too high or gel may occur. , The hydroxyl group-containing monomer is preferably 30% by weight or less, more preferably 27% by weight or less, and 25% by weight or less with respect to the total amount of the monofunctional monomer component forming the (meth)acrylic polymer. is more preferred.

In addition, the monomer component forming the (meth)acrylic polymer may contain other functional group-containing monomers as monofunctional monomers, such as carboxyl group-containing monomers and monomers having a cyclic ether group. be done.

As the carboxyl group-containing monomer, those having a polymerizable functional group having an unsaturated double bond such as a (meth)acryloyl group or a vinyl group and having a carboxyl group can be used without particular limitation. Examples of carboxyl group-containing monomers include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid. Can be used alone or in combination. Anhydrides of itaconic acid and maleic acid can be used. Among these, acrylic acid and methacrylic acid are preferred, and acrylic acid is particularly preferred. Any carboxyl group-containing monomer can be used as the monomer component used for producing the (meth)acrylic polymer of the present invention, while the carboxyl group-containing monomer may not be used.

As the monomer having a cyclic ether group, those having a polymerizable functional group having an unsaturated double bond such as a (meth)acryloyl group or a vinyl group and having a cyclic ether group such as an epoxy group or an oxetane group are used. It can be used without any particular limitation. Examples of epoxy group-containing monomers include glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether, and the like. Examples of oxetane group-containing monomers include 3-oxetanylmethyl (meth)acrylate, 3-methyl-oxetanylmethyl (meth)acrylate, 3-ethyl-oxetanylmethyl (meth)acrylate, and 3-butyl-oxetanylmethyl (meth)acrylate. , 3-hexyl-oxetanylmethyl (meth)acrylate and the like. These can be used alone or in combination.

In the present invention, the carboxyl group-containing monomer and the monomer having a cyclic ether group are preferably 30% by weight or less, and 27% by weight, based on the total amount of the monofunctional monomer component forming the (meth)acrylic polymer. % or less is more preferable, and 25% by weight or less is even more preferable.

Examples of monomer components for forming the (meth)acrylic polymer of the present invention include, as copolymerization monomers, CH ₂ ═C(R ¹ )COOR ² (R ¹ is hydrogen or a methyl group, R ² is the number of carbon atoms 1 to 3 substituted alkyl groups and cyclic cycloalkyl groups.) include alkyl (meth)acrylates.

Here, the substituent of the substituted alkyl group having 1 to 3 carbon atoms as R ² is preferably an aryl group having 3 to 8 carbon atoms or an aryloxy group having 3 to 8 carbon atoms. . The aryl group is preferably, but not limited to, a phenyl group.

Examples of such monomers represented by CH ₂ ═C(R ¹ )COOR ² include phenoxyethyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, 3,3,5-trimethylcyclohexyl (Meth)acrylate, isobornyl (meth)acrylate and the like. These can be used alone or in combination.

In the present invention, the (meth)acrylate represented by CH ₂ ═C(R ¹ )COOR ² is 50% by weight or less with respect to the total amount of monofunctional monomer components forming the (meth)acrylic polymer. 45% by weight or less is preferable, 40% by weight or less is more preferable, and 35% by weight or less is even more preferable.

Other copolymerizable monomers include vinyl acetate, vinyl propionate, styrene, α-methylstyrene; polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxyethylene glycol (meth)acrylate, (meth)acrylate, Glycol-based acrylic ester monomers such as methoxypolypropylene glycol acrylate; acrylic ester-based monomers such as tetrahydrofurfuryl (meth)acrylate, fluorine (meth)acrylate, silicone (meth)acrylate and 2-methoxyethyl acrylate; amide group-containing Monomers, amino group-containing monomers, imide group-containing monomers, N-acryloylmorpholine, vinyl ether monomers and the like can also be used. As the copolymerizable monomer, a monomer having a cyclic structure such as terpene (meth)acrylate and dicyclopentanyl (meth)acrylate can be used.

Furthermore, silane-based monomers containing silicon atoms and the like are included. Examples of silane monomers include 3-acryloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltriethoxysilane, 8-vinyloctyltrimethoxysilane. , 8-vinyloctyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltriethoxysilane, 10-acryloyloxydecyltriethoxysilane and the like.

The monomer component forming the (meth)acrylic polymer of the present invention contains, in addition to the monofunctional monomers exemplified above, a polyfunctional monomer as necessary in order to adjust the cohesive force of the pressure-sensitive adhesive. be able to.

Polyfunctional monomers are monomers having at least two polymerizable functional groups having unsaturated double bonds such as (meth)acryloyl groups or vinyl groups, for example, (poly)ethylene glycol di(meth)acrylate, (Poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,2-ethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate, etc. Ester compounds of polyhydric alcohol and (meth)acrylic acid; allyl (meth)acrylate, vinyl (meth)acrylate, divinylbenzene, epoxy acrylate, polyester acrylate, urethane acrylate, butyl di(meth)acrylate, hexyl di(meth)acrylate, etc. is mentioned. Among these, trimethylolpropane tri(meth)acrylate, hexanediol di(meth)acrylate, and dipentaerythritol hexa(meth)acrylate can be preferably used. A polyfunctional monomer can be used individually by 1 type or in combination of 2 or more types.

The amount of the polyfunctional monomer used varies depending on its molecular weight, the number of functional groups, etc., but it is preferably used in an amount of 3 parts by weight or less, more preferably 2 parts by weight or less, with respect to a total of 100 parts by weight of the monofunctional monomers. 1 part by weight or less is more preferable. Although the lower limit is not particularly limited, it is preferably 0 parts by weight or more, more preferably 0.001 parts by weight or more. Adhesive strength can be improved by setting the amount of the polyfunctional monomer to be used within the above range.

For the production of the (meth)acrylic polymer, known production methods such as solution polymerization, radiation polymerization such as ultraviolet (UV) polymerization, bulk polymerization, various radical polymerization such as emulsion polymerization, and the like can be appropriately selected. The (meth)acrylic polymer to be obtained may be any of random copolymers, block copolymers, graft copolymers, and the like.

In addition, in the present invention, a partially polymerized product of the above monomer component can also be suitably used.

When the (meth)acrylic polymer is produced by radical polymerization, polymerization can be carried out by appropriately adding polymerization initiators, chain transfer agents, emulsifiers, etc. used for radical polymerization to the monomer components. The polymerization initiator, chain transfer agent, emulsifier and the like used in the radical polymerization are not particularly limited and can be appropriately selected and used. The weight-average molecular weight of the (meth)acrylic polymer can be controlled by adjusting the amount of the polymerization initiator and the chain transfer agent used and the reaction conditions, and the amount used is appropriately adjusted according to these types.

For example, in solution polymerization or the like, ethyl acetate, toluene, or the like is used as a polymerization solvent. As a specific example of solution polymerization, the reaction is carried out under an inert gas stream such as nitrogen, adding a polymerization initiator, and generally at a temperature of about 50 to 70° C. for about 5 to 30 hours.

Examples of thermal polymerization initiators used for solution polymerization include 2,2′-azobisisobutyronitrile, 2,2′-azobis-2-methylbutyronitrile, 2,2′-azobis(2 -methylpropionate) dimethyl, 4,4'-azobis-4-cyanovaleric acid, azobisisovaleronitrile, 2,2'-azobis(2-amidinopropane) dihydrochloride, 2,2'-azobis[2- (5-methyl-2-imidazolin-2-yl)propane]dihydrochloride, 2,2′-azobis(2-methylpropionamidine) disulfate, 2,2′-azobis(N,N′-dimethylene isobutyl amidine), 2,2′-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] hydrate (VA-057, manufactured by Wako Pure Chemical Industries, Ltd.) and other azo initiators; persulfate potassium, persulfates such as ammonium persulfate, di(2-ethylhexyl)peroxydicarbonate, di(4-t-butylcyclohexyl)peroxydicarbonate, di-sec-butylperoxydicarbonate, t-butylperoxy Neodecanoate, t-hexyl peroxypivalate, t-butyl peroxypivalate, dilauroyl peroxide, di-n-octanoyl peroxide, 1,1,3,3-tetramethylbutylperoxy-2 - ethylhexanoate, di(4-methylbenzoyl) peroxide, dibenzoyl peroxide, t-butyl peroxyisobutyrate, 1,1-di(t-hexylperoxy) cyclohexane, t-butyl hydroperoxide, Examples include peroxide-based initiators such as hydrogen peroxide, combinations of persulfate and sodium hydrogen sulfite, and redox-based initiators that combine peroxides and reducing agents, such as combinations of peroxides and sodium ascorbate. can be, but are not limited to.

The polymerization initiator may be used alone or in combination of two or more. It is preferably about 1 part by weight or less with respect to 100 parts by weight of the total amount of the monomer components. , more preferably about 0.005 to 1 part by weight, more preferably about 0.02 to 0.5 part by weight.

When 2,2'-azobisisobutyronitrile is used as the polymerization initiator, the amount of the polymerization initiator used is about 0.2 parts by weight or less with respect to 100 parts by weight of the total amount of the monomer components. 0.06 to 0.2 parts by weight is more preferable.

Chain transfer agents include, for example, lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolate, 2,3-dimercapto-1-propanol and the like. The chain transfer agent may be used alone or in combination of two or more. The total content is 0.3 parts by weight per 100 parts by weight of the total monomer components less than a degree.

Examples of emulsifiers used in emulsion polymerization include anionic emulsifiers such as sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, ammonium polyoxyethylene alkyl ether sulfate, and sodium polyoxyethylene alkylphenyl ether sulfate; Examples include nonionic emulsifiers such as ethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene fatty acid esters, and polyoxyethylene-polyoxypropylene block polymers. These emulsifiers may be used alone or in combination of two or more.

Furthermore, as reactive emulsifiers, emulsifiers into which a radically polymerizable functional group such as a propenyl group or an allyl ether group is introduced, specifically, for example, Aqualon HS-10, HS-20, KH-10, BC-05 , BC-10, BC-20 (all of which are manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), Adekaria Soap SE10N (manufactured by ADEKA), and the like. The amount of the emulsifier used is preferably 5 parts by weight or less with respect to 100 parts by weight of the total amount of the monomer components.

When the (meth)acrylic polymer is produced by radiation polymerization, it can be produced by irradiating the monomer component with radiation such as electron beams and ultraviolet rays (UV) for polymerization. Among these, ultraviolet polymerization is preferred. Ultraviolet polymerization, which is a preferred embodiment of radiation polymerization, will be described below.

When performing ultraviolet polymerization, it is preferable to allow the monomer component to contain a photopolymerization initiator because of the advantage that the polymerization time can be shortened. Therefore, when performing ultraviolet polymerization, for example, a monomer component containing the alkyl (meth) acrylate and / or a partially polymerized product of the monomer component, an ultraviolet absorber, a dye compound, and an ultraviolet curable acrylic containing a photopolymerization initiator It is preferably formed by UV-polymerizing the adhesive composition. The pressure-sensitive adhesive layer formed by ultraviolet polymerization of the UV-curable acrylic pressure-sensitive adhesive composition can be formed with a thickness of 150 μm or more, and a pressure-sensitive adhesive layer with a wide range of thicknesses can be formed. preferable.

Although the photopolymerization initiator is not particularly limited, it preferably contains a photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more. In the case where the pressure-sensitive adhesive composition contains an ultraviolet absorber or a dye compound, the ultraviolet light is absorbed by the ultraviolet absorber or the dye compound when it is subjected to ultraviolet polymerization, so that sufficient polymerization cannot be performed. However, a photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more is preferable because it can be sufficiently polymerized in spite of containing an ultraviolet absorber and a dye compound.

As the photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (Irgacure 819, manufactured by BASF), 2,4,6-trimethylbenzoyl- Diphenyl-phosphine oxide (LUCIRIN TPO, manufactured by BASF) and the like can be mentioned.

The photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more may be used alone or in combination of two or more.

In addition, the amount of the photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more is not particularly limited, but it is preferably less than the amount of the ultraviolet absorber or dye compound to be described later. It is preferably about 0.005 to 1 part by weight, more preferably about 0.02 to 0.8 part by weight, relative to 100 parts by weight of the monofunctional monomer component forming the (meth)acrylic polymer. preferable. It is preferable that the amount of the photopolymerization initiator (A) to be added is within the above range because the ultraviolet polymerization can sufficiently proceed.

Further, the photopolymerization initiator may contain a photopolymerization initiator (B) having an absorption band at a wavelength of less than 400 nm. The photopolymerization initiator (B) is not particularly limited as long as it generates radicals by ultraviolet rays and initiates photopolymerization and has an absorption band at a wavelength of less than 400 nm. Any initiator can be suitably used. For example, benzoin ether-based photopolymerization initiator, acetophenone-based photopolymerization initiator, α-ketol-based photopolymerization initiator, photoactive oxime-based photopolymerization initiator, benzoin-based photopolymerization initiator, benzyl-based photopolymerization initiator, benzophenone A photopolymerization initiator, a ketal photopolymerization initiator, a thioxanthone photopolymerization initiator, an acylphosphine oxide photopolymerization initiator, and the like can be used.

Specifically, benzoin ether-based photopolymerization initiators include, for example, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2,2-dimethoxy-1,2-diphenylethane- 1-one, anisole methyl ether and the like.

Acetophenone-based photopolymerization initiators include, for example, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexylphenylketone, 4-phenoxydichloroacetophenone, and 4-t-butyldichloroacetophenone. etc.

Examples of α-ketol photopolymerization initiators include 2-methyl-2-hydroxypropiophenone, 1-[4-(2-hydroxyethyl)phenyl]-2-hydroxy-2-methylpropan-1-one, and the like. is mentioned.

Examples of photoactive oxime-based photopolymerization initiators include 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)-oxime.

Benzoin-based photopolymerization initiators include, for example, benzoin.

Examples of benzyl-based photopolymerization initiators include benzyl and the like.

Benzophenone-based photopolymerization initiators include, for example, benzophenone, benzoylbenzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, polyvinylbenzophenone, α-hydroxycyclohexylphenyl ketone, and the like.

Ketal photopolymerization initiators include benzyl dimethyl ketal and the like.

Thioxanthone photopolymerization initiators include, for example, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, 2,4 - including diisopropylthioxanthone, dodecylthioxanthone, and the like.

Acylphosphine oxide photopolymerization initiators include, for example, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide and the like.

The photopolymerization initiator (B) having an absorption band at a wavelength of less than 400 nm can be used alone or in combination of two or more. The photopolymerization initiator (B) having an absorption band at a wavelength of less than 400 nm can be added within a range that does not impair the effects of the present invention. It is preferably about 0.005 to 0.5 parts by weight, more preferably about 0.02 to 0.2 parts by weight, based on 100 parts by weight of the organic monomer component.

In the present invention, when the monomer component is subjected to ultraviolet polymerization, a photopolymerization initiator (B) having an absorption band at a wavelength of less than 400 nm is first added to the monomer component, and the monomer component is partially polymerized by irradiation with ultraviolet light. It is preferable to add a photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more, an ultraviolet absorber and a dye compound to the partially polymerized product (prepolymer composition) of the monomer components, followed by ultraviolet polymerization. When adding the photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more to the partially polymerized monomer component (prepolymer composition) partially polymerized by ultraviolet irradiation, the photopolymerization initiation It is preferable to add the agent after dissolving it in the monomer.

(2) Ultraviolet absorber The ultraviolet absorber is not particularly limited, but examples thereof include triazine-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, oxybenzophenone-based ultraviolet absorbers, and salicylic acid ester-based ultraviolet absorbers. Absorbents, cyanoacrylate-based ultraviolet absorbers, and the like can be mentioned, and these can be used alone or in combination of two or more. Among these, triazine-based UV absorbers and benzotriazole-based UV absorbers are preferred, triazine-based UV absorbers having two or less hydroxyl groups in one molecule, and benzotriazole having one benzotriazole skeleton in one molecule. At least one UV absorber selected from the group consisting of triazole-based UV absorbers has good solubility in the monomer used to form the acrylic pressure-sensitive adhesive composition and has a wavelength of around 380 nm. It is preferable because it has a high ultraviolet absorption capacity at .

Specific examples of triazine-based UV absorbers having two or less hydroxyl groups in one molecule include 2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]-6 -(4-methoxyphenyl)-1,3,5-triazine (Tinosorb S, manufactured by BASF), 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl) -1,3,5-triazine (TINUVIN 460, manufactured by BASF), 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and [(C10-C16 (mainly C12-C13) alkyloxy) methyl] oxirane (TINUVIN400, manufactured by BASF), 2-[4,6-bis(2,4-dimethylphenyl)-1,3 ,5-triazin-2-yl]-5-[3-(dodecyloxy)-2-hydroxypropoxy]phenol), 2-(2,4-dihydroxyphenyl)-4,6-bis-(2,4- Dimethylphenyl)-1,3,5-triazine and (2-ethylhexyl)-glycidate reaction product (TINUVIN405, manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triazine-2 -yl)-5-[(hexyl)oxy]-phenol (TINUVIN1577, manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[2-(2- ethylhexanoyloxy)ethoxy]-phenol (ADK STAB LA46, manufactured by ADEKA), 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)- 1,3,5-triazine (TINUVIN479, manufactured by BASF) and the like can be mentioned.

Further, as a benzotriazole-based UV absorber having one benzotriazole skeleton in one molecule, 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4- (1,1,3,3-tetramethylbutyl) phenol (TINUVIN 928, manufactured by BASF), 2-(2-hydroxy-5-tert-butylphenyl)-2H-benzotriazole (TINUVIN PS, manufactured by BASF), benzene Ester compound of propanoic acid and 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy (C7-9 side chain and straight chain alkyl) (TINUVIN384-2, BASF ), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (TINUVIN900, manufactured by BASF), 2-(2H-benzotriazol-2-yl )-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (TINUVIN928, manufactured by BASF), methyl-3-(3-(2H-benzotriazole -2-yl)-5-t-butyl-4-hydroxyphenyl)propionate/polyethylene glycol 300 reaction product (TINUVIN1130, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-p-cresol ( TINUVIN P, manufactured by BASF), 2(2H-benzotriazol-2-yl)-4-6-bis(1-methyl-1-phenylethyl)phenol (TINUVIN234, manufactured by BASF), 2-[5-chloro (2H )-benzotriazol-2-yl]-4-methyl-6-(tert-butyl)phenol (TINUVIN326, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6-di-tert- Pentylphenol (TINUVIN328, manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol (TINUVIN329, manufactured by BASF), methyl 3-(3 -(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate reaction product with polyethylene glycol 300 (TINUVIN213, manufactured by BASF), 2-(2H-benzotriazole-2- yl)-6-dodecyl-4-methylphenol (TINUVIN571, manufactured by BASF), 2-[2-hydroxy-3-(3,4,5,6-tetrahydrophthalimidomethyl)-5-methylphenyl]benzotriazole (Sumisorb250, manufactured by Sumitomo Chemical Co., Ltd.) etc. can be mentioned.

Examples of the benzophenone-based ultraviolet absorber (benzophenone-based compound) and oxybenzophenone-based ultraviolet absorber (oxybenzophenone-based compound) include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy -4-methoxybenzophenone-5-sulfonic acid (anhydrous and trihydrate), 2-hydroxy-4-octyloxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 4-benzyloxy-2-hydroxybenzophenone, 2, 2',4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4-dimethoxybenzophenone and the like can be mentioned.

Examples of the salicylic acid ester-based ultraviolet absorbers (salicylic acid ester-based compounds) include phenyl-2-acryloyloxybenzoate, phenyl-2-acryloyloxy-3-methylbenzoate, and phenyl-2-acryloyloxy. -4-methylbenzoate, phenyl-2-acryloyloxy-5-methylbenzoate, phenyl-2-acryloyloxy-3-methoxybenzoate, phenyl-2-hydroxybenzoate, phenyl-2-hydroxy -3-methylbenzoate, phenyl-2-hydroxy-4-methylbenzoate, phenyl-2-hydroxy-5-methylbenzoate, phenyl 2-hydroxy-3-methoxybenzoate, 2,4-di-tert -butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate (TINUVIN120, manufactured by BASF) and the like.

Examples of the cyanoacrylate-based ultraviolet absorbers (cyanoacrylate-based compounds) include alkyl-2-cyanoacrylates, cycloalkyl-2-cyanoacrylates, alkoxyalkyl-2-cyanoacrylates, alkenyl-2-cyanoacrylates, alkynyl- 2-cyanoacrylate and the like can be mentioned.

The maximum absorption wavelength of the absorption spectrum of the ultraviolet absorber is preferably in the wavelength range of 300-400 nm, more preferably in the wavelength range of 320-380 nm. The method for measuring the maximum absorption wavelength is the same as the method for measuring the dye-based compound, which will be described later.

The ultraviolet absorber may be used alone or in combination of two or more, but the total content is the monofunctional monomer component forming the (meth)acrylic polymer. It is preferably about 0.1 to 5 parts by weight, more preferably about 0.5 to 3 parts by weight, per 100 parts by weight. By setting the amount of the ultraviolet absorber to be added in the above range, the ultraviolet absorbing function of the pressure-sensitive adhesive layer can be sufficiently exhibited, and when ultraviolet polymerization is performed, the polymerization is not hindered, which is preferable.

(3) Dye Compound The dye compound used in the present invention is not particularly limited as long as it is a compound whose absorption spectrum has a maximum absorption wavelength in the wavelength region of 380 to 430 nm. The maximum absorption wavelength of the absorption spectrum of the dye compound is more preferably in the wavelength region of 380-420 nm. In the present invention, by using such a dye compound and the ultraviolet absorber in combination, it is possible to sufficiently absorb light in a region (wavelength 380 nm to 430 nm) that does not affect the light emission of the organic EL element, and The light-emitting region of the organic EL element (on the longer wavelength side than 430 nm) is sufficiently permeable, and as a result, deterioration of the organic EL element due to external light can be suppressed. The dye compound is not particularly limited as long as it has the above wavelength characteristics, but a material that does not impair the display properties of the organic EL element and does not have fluorescence and phosphorescence (photoluminescence) is preferable.

The half width of the dye compound is not particularly limited, but is preferably 80 nm or less, more preferably 5 to 70 nm, and even more preferably 10 to 60 nm. When the half-value width of the dye compound is within the above range, it is possible to sufficiently absorb light in a region that does not affect the light emission of the organic EL element, and sufficiently transmit light with a wavelength longer than 430 nm. Therefore, it is preferable. In addition, the method for measuring the half-value width is according to the method described below.
<Method for measuring half-value width>
The half width of the dye compound was measured from the transmission absorption spectrum of the dye compound solution under the following conditions using an ultraviolet-visible spectrophotometer (U-4100, manufactured by Hitachi High-Tech Science Co., Ltd.). From the spectrum measured by adjusting the concentration so that the absorbance at the maximum absorption wavelength is 1.0, the wavelength interval (full width at half maximum) between two points at 50% of the peak value was taken as the half width of the dye compound. .
(Measurement condition)
Solvent: Toluene or chloroform Cell: Quartz cell Optical path length: 10 mm

The dye compound is not particularly limited as long as it has a maximum absorption wavelength in the absorption spectrum of 380 to 430 nm. Examples of the dye compound include organic dye compounds and inorganic dye compounds. Among these, from the viewpoint of dispersibility in a resin component such as a base polymer and maintenance of transparency, an organic dye is preferred. Compounds are preferred.

Examples of the organic dye compound include azomethine compounds, indole compounds, cinnamic acid compounds, pyrimidine compounds, and porphyrin compounds.

As the organic dye compound, commercially available compounds can be suitably used. Specifically, as the indole compound, BONASORB UA3911 (trade name, maximum absorption wavelength of absorption spectrum: 398 nm, half width: 48 nm, manufactured by Orient Chemical Industry Co., Ltd.), BONASORB UA3912 (trade name, maximum absorption wavelength of absorption spectrum: 386 nm, half width: 53 nm, manufactured by Orient Chemical Industry Co., Ltd.), and SOM as the cinnamic acid-based compound. -5-0106 (trade name, maximum absorption wavelength of absorption spectrum: 416 nm, half width: 50 nm, manufactured by Orient Chemical Industry Co., Ltd.), FDB-001 (trade name, maximum absorption wavelength of absorption spectrum) as a porphyrin compound : 420 nm, half width: 14 nm, manufactured by Yamada Chemical Industry Co., Ltd.).

The dye compound may be used alone or in combination of two or more. It is preferably about 0.01 to 10 parts by weight, more preferably about 0.02 to 5 parts by weight. By setting the amount of the dye compound added within the above range, it is possible to sufficiently absorb light in a region that does not affect the light emission of the organic EL element. This is preferable because deterioration of the organic EL element can be suppressed.

(4) Silane Coupling Agent Further, the adhesive composition of the present invention may contain a silane coupling agent. The amount of the silane coupling agent is preferably 1 part by weight or less, more preferably 0.01 to 1 part by weight, based on 100 parts by weight of the monofunctional monomer component forming the (meth)acrylic polymer. 0.02 to 0.6 parts by weight is more preferable.

Examples of the silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 2-(3,4 epoxycyclohexyl). Epoxy group-containing silane coupling agents such as ethyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-triethoxysilyl-N-(1, 3-dimethylbutylidene)propylamine, amino group-containing silane coupling agents such as N-phenyl-γ-aminopropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane and other ( Meth) acrylic group-containing silane coupling agents, isocyanate group-containing silane coupling agents such as 3-isocyanatopropyltriethoxysilane, and the like.

(5) Cross-linking agent The pressure-sensitive adhesive composition of the present invention can contain a cross-linking agent. Examples of cross-linking agents include isocyanate-based cross-linking agents, epoxy-based cross-linking agents, silicone-based cross-linking agents, oxazoline-based cross-linking agents, aziridine-based cross-linking agents, silane-based cross-linking agents, alkyl-etherified melamine-based cross-linking agents, metal chelate-based cross-linking agents, Cross-linking agents such as oxides are included. A crosslinking agent can be used alone or in combination of two or more. Among these, isocyanate-based cross-linking agents are preferably used.

The cross-linking agent may be used alone or in combination of two or more, but the total content is the monofunctional monomer that forms the (meth)acrylic polymer. Based on 100 parts by weight of the component, it is preferably 5 parts by weight or less, more preferably 0.01 to 5 parts by weight, still more preferably 0.01 to 4 parts by weight, and 0.02 to 3 parts by weight. Especially preferred.

The isocyanate-based cross-linking agent refers to a compound having two or more isocyanate groups (including an isocyanate regenerative functional group temporarily protected by a blocking agent or a quantization of the isocyanate group) in one molecule. The isocyanate-based crosslinking agent includes aromatic isocyanates such as tolylene diisocyanate and xylene diisocyanate, alicyclic isocyanates such as isophorone diisocyanate, and aliphatic isocyanates such as hexamethylene diisocyanate.

More specifically, for example, lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate, alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate and isophorone diisocyanate, 2,4-tolylene diisocyanate, Aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, polymethylene polyphenyl isocyanate, trimethylolpropane/tolylene diisocyanate trimer adduct (trade name: Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd.) ), trimethylolpropane/hexamethylene diisocyanate trimer adduct (trade name: Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.), isocyanurate of hexamethylene diisocyanate (trade name: Coronate HX, Nippon Polyurethane Industry Co., Ltd.) ), trimethylolpropane adduct of xylylene diisocyanate (trade name: D110N, manufactured by Mitsui Chemicals, Inc.), trimethylolpropane adduct of hexamethylene diisocyanate (trade name: D160N, Mitsui Chemicals, Inc.). ); polyether polyisocyanates, polyester polyisocyanates, adducts of these with various polyols, and polyisocyanates multifunctionalized with isocyanurate bonds, biuret bonds, allophanate bonds, and the like.

(6) Other Additives The pressure-sensitive adhesive composition of the present invention may contain appropriate additives in addition to the components described above, depending on the application. For example, tackifiers (for example, rosin derivative resins, polyterpene resins, petroleum resins, oil-soluble phenolic resins, etc., which are solid, semi-solid, or liquid at room temperature); fillers such as hollow glass balloons; plasticizers; aging Inhibitors; light stabilizers (HALS); antioxidants and the like.

In the present invention, the pressure-sensitive adhesive composition is preferably adjusted to have a viscosity suitable for work such as coating on a substrate. The viscosity of the pressure-sensitive adhesive composition is adjusted, for example, by adding various polymers such as thickening additives, polyfunctional monomers, etc., or by partially polymerizing the monomer components in the pressure-sensitive adhesive composition. The partial polymerization may be performed before or after adding various polymers such as thickening additives, polyfunctional monomers, and the like. Since the viscosity of the pressure-sensitive adhesive composition changes depending on the amount of additives, etc., the polymerization rate when partially polymerizing the monomer components in the pressure-sensitive adhesive composition cannot be uniquely determined, but as a guideline, it is about 20% or less. is preferable, about 3 to 20% is more preferable, and about 5 to 15% is even more preferable. If it exceeds 20%, the viscosity becomes too high, making it difficult to apply to the substrate.

2. Adhesive layer for organic EL display device The adhesive layer for organic EL display device of the present invention is characterized by being formed from the adhesive composition for organic EL display device.

The method for forming the pressure-sensitive adhesive layer is not particularly limited, and it can be formed by a method commonly used in this field. Specifically, the pressure-sensitive adhesive composition is applied to at least one side of a substrate, and a coating film formed from the pressure-sensitive adhesive composition is formed by drying, or irradiated with active energy rays such as ultraviolet rays. can be formed by

The substrate is not particularly limited, and for example, various substrates such as release films and transparent resin film substrates, and polarizing films described later can be suitably used as substrates.

Examples of the constituent material of the release film include resin films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester films; porous materials such as paper, cloth, and nonwoven fabric; nets; foam sheets; A suitable thin leaf material such as a resin film is preferably used because of its excellent surface smoothness.

Examples of the resin film include polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polybutylene terephthalate film, polyurethane film, and ethylene. - Vinyl acetate copolymer film and the like.

The thickness of the release film is usually 5 to 200 μm, preferably about 5 to 100 μm. For the release film, if necessary, a release agent such as a silicone-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based release agent, a release and antifouling treatment using silica powder or the like, a coating type, a kneading type, An antistatic treatment such as a vapor deposition type can also be applied. In particular, by subjecting the surface of the release film to a release treatment such as silicone treatment, long-chain alkyl treatment, or fluorine treatment as appropriate, the releasability from the pressure-sensitive adhesive layer can be further enhanced.

The transparent resin film substrate is not particularly limited, but various transparent resin films are used. The resin film is formed of one layer of film. For example, the materials include polyester resins such as polyethylene terephthalate and polyethylene naphthalate, acetate resins, polyethersulfone resins, polycarbonate resins, polyamide resins, polyimide resins, polyolefin resins, and (meth)acrylic resins. , polyvinyl chloride-based resins, polyvinylidene chloride-based resins, polystyrene-based resins, polyvinyl alcohol-based resins, polyarylate-based resins, polyphenylene sulfide-based resins, and the like. Among these, particularly preferred are polyester-based resins, polyimide-based resins and polyethersulfone-based resins.

The thickness of the film substrate is preferably 15-200 μm, more preferably 25-188 μm.

Methods for applying the pressure-sensitive adhesive composition onto the substrate include roll coating, kiss roll coating, gravure coating, reverse coating, roll brushing, spray coating, dip roll coating, bar coating, knife coating, air knife coating, and curtain coating. A known appropriate method such as coating, lip coating, die coating, etc. can be used, and is not particularly limited.

When the pressure-sensitive adhesive layer is formed by drying a coating film formed from the pressure-sensitive adhesive composition, the drying conditions (temperature, time) are not particularly limited. It can be appropriately set depending on the concentration and the like, but for example, it is about 60 to 170° C., preferably 60 to 150° C., for 1 to 60 minutes, preferably 2 to 30 minutes.

When the pressure-sensitive adhesive composition is an ultraviolet-curable pressure-sensitive adhesive composition and is formed by irradiating a coating film formed from the ultraviolet-curable pressure-sensitive adhesive composition with ultraviolet rays, the illuminance of the irradiated ultraviolet rays is 5 mW / cm ² or more is preferred. When the illuminance of the ultraviolet rays is less than 5 mW/cm ² , the polymerization reaction time becomes long, which may lead to poor productivity. The illuminance of the ultraviolet rays is preferably 200 mW/cm ² or less. When the illuminance of the ultraviolet rays exceeds 200 mW/cm ² , the photopolymerization initiator is rapidly consumed, resulting in a decrease in the molecular weight of the polymer and a reduction in holding power, especially at high temperatures. Further, it is preferable that the cumulative light quantity of ultraviolet rays is 100 mJ/cm ² to 5000 mJ/cm ² .

Although the ultraviolet lamp used in the present invention is not particularly limited, an LED lamp is preferable. Since the LED lamp emits less heat than other ultraviolet lamps, the temperature during polymerization of the pressure-sensitive adhesive layer can be suppressed. Therefore, it is possible to prevent the polymer from having a low molecular weight, prevent a decrease in the cohesive strength of the pressure-sensitive adhesive layer, and increase the holding power at high temperatures when used as a pressure-sensitive adhesive sheet. It is also possible to combine a plurality of ultraviolet lamps. It is also possible to intermittently irradiate ultraviolet rays and provide a light period during which ultraviolet rays are irradiated and a dark period during which ultraviolet rays are not irradiated.

In the present invention, the final polymerization rate of the monomer component in the UV-curable pressure-sensitive adhesive composition is preferably 90% or higher, more preferably 95% or higher, even more preferably 98% or higher.

In the present invention, the peak wavelength of the ultraviolet rays irradiated to the ultraviolet-curable pressure-sensitive adhesive composition is preferably in the range of 200 to 500 nm, more preferably in the range of 300 to 450 nm. If the peak wavelength of ultraviolet rays exceeds 500 nm, the photopolymerization initiator may not decompose and the polymerization reaction may not start. Moreover, when the peak wavelength of the ultraviolet rays is less than 200 nm, the polymer chains may be cut and the adhesive properties may deteriorate.

Since the reaction is inhibited by oxygen in the air, in order to block oxygen, a release film or the like is formed on the coating film formed from the UV-curable acrylic pressure-sensitive adhesive composition, or the photopolymerization reaction is carried out with nitrogen. It is preferable to carry out under atmospheric conditions. Examples of the release film include those described above. In addition, when a release film is used, the release film can be used as it is as a separator for the polarizing film with an adhesive layer.

Further, when the ultraviolet curable pressure-sensitive adhesive composition used in the present invention contains a photopolymerization initiator (B), a monomer component containing an alkyl (meth)acrylate and the photopolymerization initiator (B)
A composition containing (sometimes referred to as a "pre-addition polymerization initiator") is irradiated with ultraviolet rays to form a partial polymer of the monomer component, and the partial polymer of the monomer component is added with an ultraviolet absorber and a dye compound. , and a photopolymerization initiator (A) having an absorption band at a wavelength of 400 nm or more (sometimes referred to as a "post-addition polymerization initiator") to prepare an ultraviolet-curable pressure-sensitive adhesive composition. The polymerization rate of the partially polymerized product is preferably about 20% or less, more preferably about 3 to 20%, and even more preferably about 5 to 15%. The ultraviolet irradiation conditions are as described above.

As described above, when forming a pressure-sensitive adhesive layer from an ultraviolet-curable pressure-sensitive adhesive composition containing a photopolymerization initiator (B), the polymerization rate of the monomer component can be increased by polymerizing in two stages as described above. It is possible to improve the ultraviolet absorption function of the pressure-sensitive adhesive layer finally produced.

The thickness of the pressure-sensitive adhesive layer is preferably 12 μm or more, more preferably 50 μm or more, even more preferably 100 μm or more, from the viewpoint of ensuring the function of absorbing light with a wavelength of less than 430 nm, and 150 μm. It is particularly preferable that it is above. Although the upper limit of the thickness of the pressure-sensitive adhesive layer is not particularly limited, it is preferably 1 mm or less. When the thickness of the pressure-sensitive adhesive layer exceeds 1 mm, it becomes difficult to transmit ultraviolet rays, it takes time to polymerize the monomer component, and problems occur in processability, winding and transportability in the process, and productivity is inferior. is not preferred because of

The gel fraction of the pressure-sensitive adhesive layer of the present invention is not particularly limited, but is preferably 35% or more, more preferably 50% or more, and further preferably 75% or more. 85% or more is particularly preferred. When the gel fraction of the pressure-sensitive adhesive layer is small, the cohesive force is inferior, and problems may arise in workability and handleability.

The pressure-sensitive adhesive layer preferably has a haze value of 2% or less, more preferably 0 to 1.5%, even more preferably 0 to 1%, when measured at a thickness of 25 μm. It is preferable that the haze is in the above range because the pressure-sensitive adhesive layer has high transparency.

The average transmittance of the adhesive layer at a wavelength of 300 to 400 nm is preferably 5% or less, more preferably 2% or less. When the transmittance of the pressure-sensitive adhesive layer is within the above range, light in a region that does not affect light emission of the organic EL element can be sufficiently absorbed, and deterioration of the organic EL element can be suppressed.

The pressure-sensitive adhesive layer preferably has an average transmittance of 70% or more at a wavelength of 450 to 500 nm, more preferably 75% or more, and preferably has an average transmittance of 80% or more at a wavelength of 500 to 780 nm. , more preferably 85% or more. When the transmittance of the pressure-sensitive adhesive layer is within the above range, light can be sufficiently transmitted in the light emitting region (longer wavelength side than 430 nm) of the organic EL element, and an organic EL display using the pressure-sensitive adhesive layer can be obtained. The device is capable of full luminescence.

Further, the average transmittance of the pressure-sensitive adhesive layer at a wavelength of 400 to 430 nm or less can be designed according to the characteristics required for the organic EL display device. For example, from the viewpoint of sufficiently absorbing light in a region that does not affect the light emission of the organic EL element, suppressing deterioration of the organic EL element, and protecting the organic EL element, the average transmittance of the pressure-sensitive adhesive layer at a wavelength of 400 to 430 nm or less is It is preferably 30% or less, more preferably 20% or less. On the other hand, from the viewpoint of suppressing coloring of the organic EL element while protecting the organic EL element from ultraviolet light, the average transmittance of the pressure-sensitive adhesive layer at a wavelength of 400 to 430 nm or less is more than 30% and 75% or less. is preferable, and more preferably more than 30% and 65% or less.

Here, the "average transmittance at a wavelength of 300 to 400 nm" refers to the average value of the measured transmittance obtained by measuring the transmittance at a pitch of 1 nm in the wavelength region of 300 to 400 nm. The same applies to the average transmittance in other wavelength regions.

By having the above-mentioned transmittance, the pressure-sensitive adhesive layer of the present invention can sufficiently absorb light in a region that does not affect the light emission of the organic EL device, and the light emission region of the organic EL device (longer wavelength than 430 nm side) can be sufficiently transmitted, and deterioration of the organic EL element due to external light can be suppressed.

When the pressure-sensitive adhesive layer is exposed, the pressure-sensitive adhesive layer may be protected with a release film until practical use.

3. Polarizing Film with Adhesive Layer for Organic EL Display Device A polarizing film with an adhesive layer for an organic EL display device of the present invention is characterized by having a polarizing film and the above-mentioned adhesive layer for an organic EL display device.

As the pressure-sensitive adhesive layer for organic EL display devices, those described above can be preferably used. Moreover, when the pressure-sensitive adhesive layer is formed on a base material other than the polarizing film, the pressure-sensitive adhesive layer can be transferred by bonding to the polarizing film. In addition, the release film can be used as it is as a separator for a polarizing film with an adhesive layer, and the process can be simplified.

The polarizing film is not particularly limited, but may include a polarizer and a transparent protective film on at least one side of the polarizer.

(1) Polarizer The polarizer is not particularly limited, and various types can be used. As a polarizer, for example, hydrophilic polymer films such as polyvinyl alcohol films, partially formalized polyvinyl alcohol films, and partially saponified ethylene-vinyl acetate copolymer films are coated with dichroic dyes such as iodine and dichroic dyes. Polyene-based oriented films such as those obtained by adsorbing a substance and uniaxially stretched, polyvinyl alcohol dehydrated products, polyvinyl chloride dehydrochlorinated products, and the like can be mentioned. Among these, a polarizer composed of a polyvinyl alcohol film and a dichroic substance such as iodine is suitable. Although the thickness of these polarizers is not particularly limited, it is generally about 5 to 80 μm.

A polarizer obtained by dyeing a polyvinyl alcohol-based film with iodine and uniaxially stretching it can be produced, for example, by dyeing polyvinyl alcohol by immersing it in an aqueous solution of iodine and stretching it to 3 to 7 times its original length. It can also be immersed in an aqueous solution of potassium iodide or the like, which may contain boric acid, zinc sulfate, zinc chloride or the like, if necessary. Further, if necessary, the polyvinyl alcohol film may be immersed in water and washed with water before dyeing. By washing the polyvinyl alcohol film with water, dirt and anti-blocking agents on the surface of the polyvinyl alcohol film can be washed away, and by swelling the polyvinyl alcohol film, uneven dyeing can be prevented. be. Stretching may be performed after dyeing with iodine, stretching may be performed while dyeing, or dyeing with iodine may be performed after stretching. It can also be stretched in an aqueous solution of boric acid or potassium iodide or in a water bath.

A thin polarizer having a thickness of 10 μm or less can also be used in the present invention. From the viewpoint of thinning, the thickness is preferably 1 to 7 μm. Such a thin polarizer has little thickness unevenness, is excellent in visibility, is excellent in durability due to little dimensional change, and is preferable in that the thickness of the polarizing film can be reduced.

Typical examples of thin polarizers include JP-A-51-069644, JP-A-2000-338329, WO 2010/100917 pamphlet, WO 2010/100917 pamphlet, or patents A thin polarizing film described in JP-A-4751481 and JP-A-2012-073563 can be mentioned. These thin polarizing films can be obtained by a manufacturing method including a step of stretching a laminate of a polyvinyl alcohol-based resin (hereinafter also referred to as a PVA-based resin) layer and a stretching resin substrate, and a step of dyeing. According to this manufacturing method, even if the PVA-based resin layer is thin, it can be stretched without problems such as breakage due to stretching because it is supported by the stretching resin substrate.

As for the thin polarizing film, among the manufacturing methods including the step of stretching and the step of dyeing in the state of a laminate, it can be stretched at a high magnification and can improve the polarizing performance. , International Publication No. 2010/100917 pamphlet, or Patent No. 4751481 and JP 2012-073563 Those obtained by a method including a step of stretching in an aqueous boric acid solution as described are preferable, especially patent It is preferable to obtain by a manufacturing method including a step of auxiliary stretching in the air before stretching in an aqueous boric acid solution, as described in the specification of 4751481 and JP-A-2012-073563.

(2) Transparent protective film As for the transparent protective film, a conventionally used one can be appropriately used. Specifically, a transparent protective film formed from a material having excellent transparency, mechanical strength, thermal stability, moisture barrier properties, isotropy, etc. is preferable. For example, polyester-based polymers such as polyethylene terephthalate and polyethylene naphthalate , cellulose polymers such as diacetyl cellulose and triacetyl cellulose, acrylic polymers such as polymethyl methacrylate, styrene polymers such as polystyrene and acrylonitrile-styrene copolymer (AS resin), and polycarbonate polymers. In addition, polyethylene, polypropylene, polyolefins having a cyclo- or norbornene structure, polyolefin-based polymers such as ethylene-propylene copolymers, vinyl chloride-based polymers, amide-based polymers such as nylon and aromatic polyamides, imide-based polymers, and sulfone-based polymers , polyethersulfone-based polymer, polyetheretherketone-based polymer, polyphenylene sulfide-based polymer, vinyl alcohol-based polymer, vinylidene chloride-based polymer, vinyl butyral-based polymer, arylate-based polymer, polyoxymethylene-based polymer, epoxy-based polymer, or Blends of the above polymers are also included as examples of the polymer forming the transparent protective film. The transparent protective film can also be formed as a cured layer of thermosetting or ultraviolet curing resin such as acrylic, urethane, acrylic urethane, epoxy, or silicone.

Although the thickness of the transparent protective film can be determined as appropriate, it is generally about 1 to 500 μm from the viewpoints of strength, workability such as handleability, and thinness.

It is preferable that the polarizer and the transparent protective film are adhered to each other via a water-based adhesive or the like. Examples of water-based adhesives include isocyanate-based adhesives, polyvinyl alcohol-based adhesives, gelatin-based adhesives, vinyl-based latex-based adhesives, water-based polyurethanes, and water-based polyesters. In addition to the above, examples of the adhesive between the polarizer and the transparent protective film include an ultraviolet curable adhesive and an electron beam curable adhesive. The electron beam-curable polarizing film adhesive exhibits suitable adhesion to the above-described various visible-side transparent protective films. Also, the adhesive used in the present invention may contain a metallic compound filler.

The surface of the transparent protective film to which the polarizer is not adhered may be subjected to a hard coat layer, antireflection treatment, sticking prevention, diffusion or antiglare treatment.

Moreover, as the transparent protective film, any one having retardation and functioning as an optical compensation layer can be used. When a transparent protective film having retardation is used, its retardation properties can be appropriately adjusted to values required for optical compensation. A stretched film can be suitably used as such a retardation film. In the retardation film, nx=ny>nz, nx>ny, where nx is the refractive index in the slow axis direction, ny is the refractive index in the in-plane fast axis direction, and nz is the refractive index in the thickness direction. >nz, nx>ny=nz, nx>nz>ny, nz=nx>ny, nz>nx>ny, nz>nx=ny. be done. Note that nx=ny includes not only the case where nx and ny are completely the same, but also the case where nx and ny are substantially the same. Moreover, ny=nz includes not only the case where ny and nz are completely the same, but also the case where ny and nz are substantially the same.

When the polarizing film used in the present invention is used as an antireflection circular polarizing plate for an organic EL display device, the retardation film has a front retardation of the transparent protective film of 1/4 wavelength (about 100 to 170 nm). A quarter-wave plate is preferred.

When a retardation film is used as the transparent protective film, a polarizer having a transparent protective film on one surface and a retardation film on the other surface can be preferably used. In that case, the installation location of the adhesive layer is not particularly limited, and may be provided on the surface of the transparent protective film opposite to the surface in contact with the polarizer, and the polarizer of the retardation film Although it may be provided on the surface opposite to the surface in contact with the , from the viewpoint of suppressing deterioration of the organic EL element, it is preferably provided on at least one surface or both surfaces.

An example of a specific configuration of the pressure-sensitive adhesive layer-attached polarizing film for an organic EL display device of the present invention is shown in FIGS. 1(a) to 1(c). As shown in FIG. 1(a), adhesive layer 2/transparent protective film 3/polarizer 4/retardation film 5, and as shown in FIG. 1(b), transparent protective film 3/polarizer 4/retardation Film 5/adhesive layer 2, as shown in FIG. 1(c), adhesive layer 2/transparent protective film 3/polarizer 4/retardation film 5/adhesive layer 2; A laminated polarizing film 1 with an adhesive layer for an organic EL display device can be mentioned. 1(a) and 1(b), the pressure-sensitive adhesive layer 2 is the pressure-sensitive adhesive layer for an organic EL display device of the present invention, and in FIG. One may be the pressure-sensitive adhesive layer for an organic EL display device of the present invention, or both may be the pressure-sensitive adhesive layer for an organic EL display device of the present invention. In FIG. 1, the polarizing film 6 is a one-side protective polarizing film composed of the polarizer 4 and the transparent protective film 3, but is not limited to this, and the polarizer 4 and the retardation film 5. It may be both protective polarizing films with a further transparent protective film in between. Moreover, as described above, various functional layers such as a hard coat layer can be formed on the surface of the transparent protective film 3 that is not in contact with the polarizer 4 .

Moreover, when the said retardation film is laminated|stacked on a polarizer through an adhesive layer, the said adhesive layer may be the adhesive layer for organic EL displays of this invention. That is, a polarizing film with an adhesive layer for an organic EL display device has a first adhesive layer, a transparent protective film, a polarizer, a second adhesive layer, a retardation film, and a third adhesive layer in this order,
At least one pressure-sensitive adhesive layer among the first pressure-sensitive adhesive layer, the second pressure-sensitive adhesive layer, and the third pressure-sensitive adhesive layer may be the pressure-sensitive adhesive layer for an organic EL display device.

4. Organic EL Display Device The organic EL display device of the present invention uses at least one of the pressure-sensitive adhesive layer for an organic EL display device of the present invention and/or the polarizing film with the pressure-sensitive adhesive layer for an organic EL display device of the present invention. Characterized by

As an example of a specific configuration of the organic EL display device, for example, as shown in FIGS. 2 to 4, cover glass or cover plastic 7 / adhesive layer 2 / transparent protective film 3 / polarizer 4 / retardation film 5/adhesive layer 2/organic EL display panel (OLED element panel) 8 (FIG. 2); cover glass or cover plastic 7/adhesive layer 9/transparent protective film 3/polarizer 4/retardation film 5/adhesive Layer 2/organic EL display panel 8 (FIG. 3); cover glass or cover plastic 7/adhesive layer 2/sensor layer 10/adhesive layer 2/transparent protective film 3/polarizer 4/retardation film 5/adhesive An organic EL display device in which each layer is laminated in this order such as layer 2/organic EL display panel 8 (FIG. 4) can be mentioned. At least one of the pressure-sensitive adhesive layers 2 in each configuration may be the pressure-sensitive adhesive layer of the present invention, and all the pressure-sensitive adhesive layers 2 may be the pressure-sensitive adhesive layers of the present invention. In addition to the above, the organic EL display device of the present invention may contain various functional layers such as a protective film and a hard coat layer. Moreover, in lamination of each layer, a pressure-sensitive adhesive layer and/or an adhesive layer can be used as appropriate. As the pressure-sensitive adhesive layer other than the pressure-sensitive adhesive layer of the present invention, a normal pressure-sensitive adhesive layer used in this field can be appropriately used.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited to these Examples. All parts and percentages in each example are based on weight.

Production Example 1 (Production of acrylic pressure-sensitive adhesive composition (a))
A monomer mixture composed of 78 parts by weight of 2-ethylhexyl acrylate (2EHA), 18 parts by weight of N-vinyl-2-pyrrolidone (NVP), and 15 parts by weight of 2-hydroxyethyl acrylate (HEA) was photopolymerized. As agents, 1-hydroxycyclohexylphenyl ketone (trade name: Irgacure 184, having an absorption band at a wavelength of 200 to 370 nm, manufactured by BASF) 0.035 parts by weight, 2,2-dimethoxy-1,2-diphenylethane-1 -On (trade name: Irgacure 651, having an absorption band at a wavelength of 200 to 380 nm, manufactured by BASF) after blending 0.035 parts by weight, viscosity (measurement conditions: BH viscometer No. 5 rotor, 10 rpm, measurement temperature 30° C.) reached about 20 Pa·s to obtain a prepolymer composition (polymerization rate: 8%) in which a part of the above monomer component was polymerized. Next, 0.15 parts by weight of hexanediol diacrylate (HDDA) and 0.3 parts by weight of a silane coupling agent (trade name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) are added to the prepolymer composition. and mixed to obtain an acrylic pressure-sensitive adhesive composition (a).

Production Example 2 (Production of acrylic pressure-sensitive adhesive composition (b))
95 parts by weight of butyl acrylate, 5 parts by weight of acrylic acid, 0.2 parts by weight of azobisisobutyronitrile as a polymerization initiator, and After 233 parts by weight of ethyl acetate was added, nitrogen gas was flowed into the mixture and the contents were replaced with nitrogen for about 1 hour while stirring. After that, the flask was heated to 60° C. and reacted for 7 hours to obtain an acrylic polymer having a weight average molecular weight (Mw) of 1,100,000.
0.8 parts by weight of trimethylolpropane tolylene diisocyanate (trade name: Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd.) as an isocyanate-based cross-linking agent to the above acrylic polymer solution (with a solid content of 100 parts by weight); 0.1 part by weight of a silane coupling agent (trade name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) was added to prepare a pressure-sensitive adhesive composition (b) solution.

Production Example 3 (Production of adhesive layer (B1-1))
The pressure-sensitive adhesive composition (b) solution obtained in Production Example 2 was applied onto a 38 μm thick separator (polyethylene terephthalate film whose surface was treated for release) so that the thickness after drying was 12 μm. , and dried at 100°C for 3 minutes to remove the solvent and obtain an adhesive layer. After that, a cross-linking treatment was performed by heating at 50° C. for 48 hours. This adhesive layer is hereinafter referred to as "organic EL display panel side adhesive layer (B1-1)".

Production Example 4 (Production of adhesive layer (B1-2))
The pressure-sensitive adhesive composition (b) solution obtained in Production Example 2 was applied onto a 38 μm thick separator (polyethylene terephthalate-based film whose surface was subjected to release treatment) so that the thickness after drying was 23 μm. Then, the layer was dried at 100° C. for 3 minutes to remove the solvent and obtain an adhesive layer. After that, a cross-linking treatment was performed by heating at 50° C. for 48 hours. This adhesive layer is hereinafter referred to as "organic EL display panel side adhesive layer (B1-2)".

Example 1
(Production of adhesive composition (A))
The acrylic pressure-sensitive adhesive composition (a) obtained in Production Example 1 (100 parts by weight of the monomer component forming the acrylic polymer) was dissolved in butyl acrylate so that the solid content was 15%. 2,4-bis-[{4-(4-ethylhexyloxy)-4-hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazine (trade name: Tinosorb S, Table 1 , "Ultraviolet absorber (b1)" in 2, maximum absorption wavelength of absorption spectrum: 346 nm, manufactured by BASF Japan) 0.7 parts by weight (solid content weight), and bis (2,4,6-trimethylbenzoyl) - Phenylphosphine oxide (trade name: Irgacure 819, having an absorption band at a wavelength of 200 to 450 nm, manufactured by BASF Japan) 0.3 parts by weight, N-vinyl-2-pyrrolidone (NVP) with a solid content of 5% BONASORB UA3911 (trade name, indole compound, “dye compound (c1)” in Tables 1 and 2, maximum absorption wavelength of absorption spectrum: 398 nm, half width: 48 nm, Orient Chemical Industry Co., Ltd. A pressure-sensitive adhesive composition (A) was obtained by adding 0.5 parts by weight (weight of solid content) and stirring.

The pressure-sensitive adhesive composition (A) is applied onto the release-treated film of the release film so that the thickness after forming the pressure-sensitive adhesive layer is 150 μm, and then the surface of the pressure-sensitive adhesive composition layer is , a release film was attached. Thereafter, ultraviolet irradiation is performed under the conditions of illuminance: 6.5 mW/cm ² , light amount: 1500 mJ/cm ² , peak wavelength: 350 nm, and the adhesive composition layer is photocured to form the adhesive layer (A-1). formed.

Example 2
BONASORB UA3912 (trade name, indole-based compound, "colorant compound (c2 )”, maximum absorption wavelength of absorption spectrum: 386 nm, half width: 53 nm, manufactured by Orient Chemical Industry Co., Ltd.) 2.5 parts by weight (solid content weight), so that the thickness after forming the adhesive layer is 100 μm A pressure-sensitive adhesive layer (A-2) was formed in the same manner as in Example 1, except that it was applied.

Example 3
2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl) dissolved in butyl acrylate to a solids content of 15% -4-(1,1,3,3-tetramethylbutyl) phenol (trade name: Tinuvin 928, "UV absorber (b2)" in Tables 1 and 2, maximum absorption wavelength of absorption spectrum: 349 nm, BASF Japan Co., Ltd. product), and the amount added was 1.5 parts by weight (solid content weight). Further, the type of dye compound was selected from cinnamic acid compounds (sample name: SOM-5-0103, “dye compound (c3)” in Tables 1 and 2, maximum absorption wavelength of absorption spectrum: 416 nm, half width: 50 nm. , manufactured by Orient Chemical Industry Co., Ltd.), 0.2 parts by weight (solid content weight) was directly added, and the thickness after forming the adhesive layer was applied so that the thickness was 100 μm. A pressure-sensitive adhesive layer (A-3) was formed in the same manner as above.

Example 4
The amount of the ultraviolet absorber (b1) added in Example 1 was changed to 3.0 parts by weight (solid content weight), and the type of dye compound was changed to N-vinyl-2-pyrrolidone (NVP) with a solid content of 1%. A porphyrin compound (sample name: FDB-001, “dye compound (c4)” in Tables 1 and 2, maximum absorption wavelength of absorption spectrum: 420 nm, half width: 14 nm, Yamada Chemical Industry Co., Ltd. )) Forming an adhesive layer (A-4) in the same manner as in Example 1, except that 0.1 part by weight (solid content weight) was applied so that the thickness after forming the adhesive layer was 100 μm did.

Example 5
(Production of adhesive composition (B))
2,4-bis-[{4-(4-ethylhexyloxy )-4-hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazine (trade name: Tinosorb S, “UV absorber (b1)” in Tables 1 and 2, absorption spectrum Maximum absorption wavelength: 346 nm, manufactured by BASF Japan) 3 parts by weight (solid content weight), BONASORB UA3912 (trade name, indole compound, “dye compound (c2)” in Tables 1 and 2, maximum absorption spectrum Absorption wavelength: 386 nm, half width: 53 nm, manufactured by Orient Chemical Industry Co., Ltd.) 0.8 parts by weight (solid content weight) was directly added and stirred to obtain an adhesive composition (B) solution.

The resulting pressure-sensitive adhesive composition (B) solution was applied to a 38 μm thick separator (polyethylene terephthalate-based film whose surface was subjected to release treatment) so that the thickness after drying was 25 μm. The layer was dried for 3 minutes to remove the solvent to obtain an adhesive layer. After that, a cross-linking treatment was performed by heating at 50° C. for 48 hours. An adhesive layer (B) was formed.

Comparative example 1
The adhesive layer (A1-1 ) was formed.

Comparative example 2
The organic EL display panel side adhesive layer (B1-2) of Production Example 3 was used.

Comparative example 3
An adhesive layer (A1-2) was formed in the same manner as in Example 1 except that the dye compound (c1) of Example 1 was not included and the adhesive layer was coated so as to have a thickness of 100 μm after formation.

Comparative example 4
An adhesive layer (A1-3) was formed in the same manner as in Example 3, except that the dye compound (c3) was not included and the adhesive layer was coated so as to have a thickness of 150 μm after formation.

Comparative example 5
The ultraviolet absorber (b1) of Example 1 was not included, and the added amount of the dye compound (c1) was 0.3 parts by weight (solid content weight), and the adhesive layer was coated so that the thickness after formation was 100 μm. A pressure-sensitive adhesive layer (A1-4) was formed in the same manner as in Example 1, except for the above.

Comparative example 6
The pressure-sensitive adhesive layer (A1 -5) was formed.

Comparative example 7
A pressure-sensitive adhesive layer (A1-6) was formed in the same manner as in Example 3, except that the ultraviolet absorber (b2) of Example 3 was not included.

Comparative example 8
A pressure-sensitive adhesive layer (A1-7) was formed in the same manner as in Example 4, except that the ultraviolet absorber (b1) of Example 4 was not included.

Example 6
(Production of adhesive layer (A-5))
In the same manner as in Example 1, except that the added amount of the dye compound (c1) of Example 1 was 0.7 parts by weight (solid content weight), and the adhesive layer was coated so that the thickness after forming the adhesive layer was 100 μm. An adhesive layer (A-5) was formed.

(Production of polarizing film (P))
A cycloolefin polymer (COP) film with a thickness of 25 μm was attached to the visible side of a polarizer made of a stretched polyvinyl alcohol film with a thickness of 5 μm impregnated with iodine using a polyvinyl alcohol-based adhesive, and the organic EL of the polarizer was obtained. An acrylic film having a thickness of 20 μm was laminated on the display panel side surface using a polyvinyl alcohol-based adhesive to obtain a polarizing film (P). The degree of polarization of the polarizing film was 99.995.

(Manufacture of polarizing film with adhesive layer)
The adhesive layer (A-5) prepared above was laminated on the visible side of the polarizing film (P) (that is, the surface of the cycloolefin polymer (COP) film having a thickness of 25 μm). The image display unit side adhesive layer (B1-1) is laminated on the organic EL display panel side surface of the polarizing film (P) (that is, the surface of the acrylic film having a thickness of 20 μm), and a retardation film (thickness : 56 μm, material: polycarbonate) and the image display area side adhesive layer (B1-2) were laminated to form a polarizing film with an adhesive layer. The obtained polarizing film with an adhesive layer is an adhesive layer (A-5) / polarizing film (P) / organic EL display panel side adhesive layer (B1-1) / retardation film / organic EL display panel side adhesive It had the configuration of the agent layer (B1-2).

Example 7
A pressure-sensitive adhesive layer (A-6) was formed in the same manner as in Example 2, except that the added amount of the dye compound (c2) of Example 2 was changed to 0.5 parts by weight (solid content weight). Further, a polarizing film with an adhesive layer was formed in the same manner as in Example 6 except that the adhesive layer (A-6) was used.

Comparative example 9
A pressure-sensitive adhesive layer (A1-8) was formed in the same manner as in Example 6 except that the pressure-sensitive adhesive layer (A-5) of Example 6 did not contain the dye compound (c1). Further, a polarizing film with an adhesive layer was formed in the same manner as in Example 6 except that the adhesive layer (A1-8) was used.

The pressure-sensitive adhesive layer and the pressure-sensitive adhesive layer-attached polarizing film thus obtained were evaluated as follows.

<Measurement of Transmittance of Adhesive Layer>
The release film of the adhesive layer obtained in Examples and Comparative Examples was peeled off, the adhesive layer was attached to a jig for measurement, and a spectrophotometer (product name: U4100, manufactured by Hitachi High-Technologies Corporation) was used. It was measured. Transmittance was measured in a wavelength range of 300 nm to 780 nm.

<Measurement of transmittance of polarizing film with adhesive layer>
The release film of the pressure-sensitive adhesive layer-attached polarizing film obtained in Examples and Comparative Examples was peeled off and measured with a spectrophotometer (product name: U4100, manufactured by Hitachi High-Technologies Corporation). Transmittance was measured in a wavelength range of 350 nm to 780 nm.

<Adhesion>
Sheet pieces having a length of 100 mm and a width of 20 mm were cut out from the pressure-sensitive adhesive layers obtained in Examples and Comparative Examples. Next, the release film on one side of the pressure-sensitive adhesive layer was peeled off, and a PET film (trade name: Lumirror S-10, thickness: 25 μm, manufactured by Toray Industries, Inc.) was adhered (backed). Next, the other release film was peeled off, and a glass plate (trade name: soda lime glass #0050, manufactured by Matsunami Glass Industry Co., Ltd.) as a test plate was crimped under crimping conditions of one reciprocation with a 2 kg roller, A sample composed of test plate/adhesive layer (A)/PET film was prepared. The resulting sample was autoclaved (50°C, 0.5 MPa, 15 minutes) and then 23°C, 50% RH. H. It was allowed to cool for 30 minutes in an atmosphere of After standing to cool, using a tensile tester (equipment name: Autograph AG-IS, manufactured by Shimadzu Corporation), in accordance with JIS Z0237, 23 ° C., 50% R.E. H. The pressure-sensitive adhesive sheet (adhesive layer/PET film) was peeled off from the test plate under conditions of a peeling speed of 300 mm/min and a peeling angle of 180° in an atmosphere of , and the 180° peeling adhesive strength (N/20 mm) was measured.

<Total light transmittance, haze>
One of the release films was peeled off from the pressure-sensitive adhesive layers obtained in Examples and Comparative Examples, and a slide glass (trade name: white polishing No. 1, thickness: 0.8 to 1.0 mm, total light transmission Ratio: 92%, Haze: 0.2%, manufactured by Matsunami Glass Industry Co., Ltd.). Further, the other release film was peeled off to prepare a test piece having a layer structure of adhesive layer/slide glass. The total light transmittance and haze value of the test piece in the visible light region were measured using a haze meter (device name: HM-150, manufactured by Murakami Color Laboratory Co., Ltd.).

REFERENCE SIGNS LIST 1 polarizing film with adhesive layer for organic EL display device 2 adhesive layer 3 transparent protective film 4 polarizer 5 retardation film 6 polarizing film 7 cover glass or cover plastic 8 organic EL panel 9 adhesive layer 10 sensor layer

Claims (9)

A base polymer, an ultraviolet absorber, and a dye compound having a maximum absorption wavelength in the absorption spectrum of 380 to 430 nm,
The maximum absorption wavelength of the absorption spectrum of the ultraviolet absorber is in the wavelength region of 300 to 400 nm,
The ultraviolet absorber is one of a triazine-based ultraviolet absorber, a benzotriazole-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, an oxybenzophenone-based ultraviolet absorber, a salicylic acid ester-based ultraviolet absorber, and a cyanoacrylate-based ultraviolet absorber. or two or more,
The adhesive composition for an organic EL display device, wherein the dye compound is one or more of an azomethine compound, an indole compound, a cinnamic acid compound, a pyrimidine compound and a porphyrin compound. thing. 2. The pressure-sensitive adhesive composition for an organic EL display device according to claim 1, wherein the base polymer is a (meth)acrylic polymer. An adhesive layer for an organic EL display device, which is formed from the adhesive composition for an organic EL display device according to claim 1 or 2. The average transmittance at a wavelength of 300 to 400 nm is 5% or less, the average transmittance at a wavelength of 450 to 500 nm is 70% or more, and the average transmittance at a wavelength of 500 to 780 nm is 80% or more. Item 4. The pressure-sensitive adhesive layer for an organic EL display device according to item 3. A polarizing film with an adhesive layer for an organic EL display device, comprising: a polarizing film; and the adhesive layer for an organic EL display device according to claim 3 or 4 . The polarizing film is provided with a transparent protective film on one surface of the polarizer and has a retardation film on the other surface, and the adhesive layer for an organic EL display device is the polarized light of the retardation film. 6. The pressure-sensitive adhesive for an organic EL display device according to claim 5 , wherein the pressure-sensitive adhesive for an organic EL display device is provided on the surface opposite to the surface in contact with the element and/or the surface opposite to the surface in contact with the polarizer of the transparent protective film. Layered polarizing film. A polarizing film with an adhesive layer for an organic EL display device having a first adhesive layer, a transparent protective film, a polarizer, a second adhesive layer, a retardation film, and a third adhesive layer in this order,
6. The method according to claim 5 , wherein at least one of the first adhesive layer, the second adhesive layer, and the third adhesive layer is the adhesive layer for an organic EL display device. A polarizing film with an adhesive layer for an organic EL display device as described above. 8. The pressure-sensitive adhesive layer - carrying polarizing film for an organic EL display device according to claim 6 , wherein the retardation film is a quarter wavelength plate and the polarizing film is a circularly polarizing film. Claim 3 or 4 , or at least one polarizing film with an adhesive layer for an organic EL display device according to any one of claims 6 to 8 . organic EL display device.

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