WO2016098504A1 - Sealing film for electronic members - Google Patents

Abstract

Provided is a sealing film for electronic members such as a quantum dot-containing resin sheet, electronic paper and organic EL device, which has good transparency, barrier properties and adhesion to an adhesive layer. A sealing film for electronic members, wherein a coating layer, a barrier layer and a protective layer are sequentially laminated on one surface of a polyester film, and wherein the coating layer contains at least one binder resin selected from among polyester resins, urethane resins and acrylic resins. This sealing film for electronic members has a water vapor transmission rate of 0.01 g/m²/day or less as measured at a temperature of 40°C at a humidity of 90% RH in accordance with JIS-K7129B.

Description

Sealing film for electronic parts

The present invention relates to a sealing film for an electronic member such as a quantum dot-containing resin sheet, electronic paper, and organic EL, which is excellent in transparency, barrier properties, and adhesiveness with an adhesive layer, and requires high water vapor barrier properties. .

In optical applications, polyester films are widely used mainly for various display applications because of their excellent optical properties.

On the other hand, as a result of the rapid spread of display displays such as electronic paper and organic EL in recent years, alternative studies on transparent plastic films as a substitute for glass substrates from the viewpoints of weight reduction and flexibility are in earnest.

However, when the glass substrate is replaced with a transparent plastic film, the device is in a state of deterioration because moisture passes through the transparent plastic film. Therefore, a transparent plastic film having a gas barrier layer is required. However, gas barrier films used for conventional food packaging applications have insufficient moisture barrier properties and it is difficult to suppress deterioration of electronic devices. .

For use in display displays such as electronic paper and organic EL, a water vapor permeability of 0.02 g is provided by providing a cured resin layer made of a polymer and a gas barrier layer made of silicon nitride oxide on at least one side of a plastic film. A gas barrier film of / m ² / day has been proposed (Patent Document 1).

However, while the gas barrier film described in Patent Document 1 has an effect of improving gas barrier properties, it does not consider the adhesion to the adhesive layer. In addition, a gas barrier film using silicon nitride oxide as a gas barrier layer has a high refractive index of the gas barrier layer, a refractive index difference with the protective layer is increased, and the transmittance may be reduced.

Further, a gas barrier film having a water vapor barrier property of 10 ⁻⁶ g / m ² / day level by laminating a planarizing layer, a gas barrier layer, and a protective layer on a base film by an atmospheric pressure plasma CVD method has been proposed ( Patent Document 2).

However, while the gas barrier film described in Example 1 of Patent Document 2 has good gas barrier properties, the protective layer made of an inorganic polymer made of TEOS as a raw material by the atmospheric pressure CVD method does not necessarily have adhesion to the adhesive layer. Not enough.

Further, a gas barrier laminate film (Patent Document 3) in which a composite film of polyvinyl alcohol and an inorganic layered compound is laminated as a protective layer of the gas barrier film has been proposed, but when used for a display body such as a display, the appearance is whitish, There was a tendency to be inferior in transparency. Furthermore, although a gas barrier laminate film (Patent Document 4) having a configuration in which a sol-gel layer is provided as a protective layer has been proposed, the surface hardness is good, but the flexibility and adhesion to the adhesive layer may be inferior. is there.

Further, in Patent Document 5, measures for improving the gas barrier layer are taken by alternately laminating organic layers / inorganic layers, but the gas barrier property is improved, but the interlayer adhesion at the organic layer / inorganic layer interface is insufficient. there were.

JP 2009-190186 A JP 2007-83644 A JP 2003-231789 A JP 2003-326634 A Japanese Patent No. 4254350

This invention is made | formed in view of the said situation, Comprising: As a sealing film for electronic members, such as a quantum dot containing resin sheet, electronic paper, and organic EL, transparency, barrier property, and adhesion | attachment to an adhesion layer It is in providing a sealing film with favorable property.

As a result of intensive studies, the present inventor has found that the above problems can be easily solved by a sealing film having a specific configuration, and has completed the present invention.

That is, the gist of the present invention is a sealing film in which a coating layer, a barrier layer, and a protective layer are sequentially laminated on one side of a polyester film, and the coating layer is selected from a polyester resin, an acrylic resin, and a urethane resin. Containing at least one binder resin and at least one cross-linking agent selected from oxazoline compounds, melamine resins, and isocyanate compounds, according to JIS-K7129B method, temperature 40 ° C., humidity 90 It exists in the sealing film for electronic members characterized by the water vapor permeability | transmittance of the sealing film measured on the measurement conditions of% RH being 0.01 g / m < ² > / day or less.

The sealing film for electronic members of the present invention is excellent in transparency, barrier properties, and adhesiveness with an adhesive layer, and is used for electronic members such as quantum dot-containing resin sheets, electronic paper, and organic EL that require high barrier properties. It is suitable as a sealing film, and its industrial value is high.

FIG. 1 is a schematic cross-sectional view showing a laminate according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail.
First, the polyester film will be described.
The polyester film may have a single layer structure or a laminated structure. For example, the polyester film may have a multilayer structure of four layers or more as long as it does not exceed the gist of the present invention other than the two-layer or three-layer structure. There is no particular limitation.

The polyester may be a homopolyester or a copolyester. In the case of a homopolyester, those obtained by polycondensation of an aromatic dicarboxylic acid and an aliphatic glycol are preferred. Examples of the aromatic dicarboxylic acid include terephthalic acid and 2,6-naphthalenedicarboxylic acid, and examples of the aliphatic glycol include ethylene glycol, diethylene glycol, and 1,4-cyclohexanedimethanol. Representative polyester includes polyethylene terephthalate (PET) and the like. On the other hand, examples of the dicarboxylic acid component of the copolyester include isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, adipic acid, sebacic acid, and oxycarboxylic acid (eg, P-oxybenzoic acid). One or two or more types can be mentioned, and examples of the glycol component include one or more types such as ethylene glycol, diethylene glycol, propylene glycol, butanediol, 1,4-cyclohexanedimethanol, neopentyl glycol and the like. In any case, the polyester referred to in the present invention refers to a polyester that is usually 60 mol% or more, preferably 80 mol% or more of polyethylene terephthalate or the like which is an ethylene terephthalate unit.

In the polyester film, it is preferable to mix particles for the main purpose of imparting easy slipperiness. The kind of the particle to be blended is not particularly limited as long as it is a particle capable of imparting slipperiness. Specific examples thereof include silica, calcium carbonate, magnesium carbonate, barium carbonate, calcium sulfate, calcium phosphate, and phosphoric acid. Examples of the particles include magnesium, kaolin, aluminum oxide, and titanium oxide. Further, the heat-resistant organic particles described in JP-B-59-5216, JP-A-59-217755 and the like may be used. Examples of other heat-resistant organic particles include thermosetting urea resins, thermosetting phenol resins, thermosetting epoxy resins, benzoguanamine resins, and the like. Furthermore, precipitated particles obtained by precipitating and finely dispersing a part of a metal compound such as a catalyst during the polyester production process can also be used.

On the other hand, the shape of the particles is not particularly limited, and any of a spherical shape, a block shape, a rod shape, a flat shape, and the like may be used. Moreover, there is no restriction | limiting in particular about the hardness, specific gravity, a color, etc. These series of particles may be used in combination of two or more as required.

The average particle diameter of the particles is usually in the range of 0.01 to 3 μm, preferably 0.01 to 1 μm. When the average particle diameter is less than 0.01 μm, the particles are likely to aggregate and dispersibility may be insufficient. On the other hand, when the average particle diameter exceeds 3 μm, the surface roughness of the film becomes too rough and There may be a problem when a release layer is applied in the process.

Furthermore, the content of the particles is usually in the range of 0.001 to 5% by weight, preferably 0.005 to 3% by weight. When the particle content is less than 0.001% by weight, the slipperiness of the film may be insufficient. On the other hand, when the content exceeds 5% by weight, the transparency of the film is insufficient. There is.

The method for adding particles to the polyester film is not particularly limited, and a conventionally known method can be adopted. For example, it can be added at any stage of producing the polyester constituting each layer, but preferably a polycondensation reaction may be carried out after the esterification stage or after the transesterification reaction.

Also, a method of blending a slurry of particles dispersed in ethylene glycol or water with a vented kneading extruder and a polyester raw material, or a blending of dried particles and a polyester raw material using a kneading extruder. It is done by methods.

In addition to the above-mentioned particles, conventionally known fluorescent whitening agents, antioxidants, antistatic agents, thermal stabilizers, lubricants, dyes, pigments and the like can be added to the polyester film as necessary. .

The thickness of the polyester film is not particularly limited as long as it can be formed as a film. In consideration of the mechanical strength, flexibility, transparency, etc. of the film substrate, the thickness is preferably 12 to 125 μm, more preferably 25 to 100 μm.

The production example of the polyester film will be specifically described, but is not limited to the following production example.

First, a method in which the polyester raw material described above is used and the molten sheet extruded from the die is cooled and solidified with a cooling roll to obtain an unstretched sheet is preferable. In this case, in order to improve the flatness of the sheet, it is necessary to improve the adhesion between the sheet and the rotary cooling drum, and an electrostatic application adhesion method and / or a liquid application adhesion method are preferably employed. Next, the obtained unstretched sheet is stretched in the biaxial direction. In that case, first, the unstretched sheet is stretched in one direction by a roll or a tenter type stretching machine. The stretching temperature is usually 70 to 120 ° C., preferably 80 to 110 ° C., and the stretching ratio is usually 2.5 to 7 times, preferably 3.0 to 6 times. Next, the stretching temperature orthogonal to the first-stage stretching direction is usually 70 to 170 ° C., and the draw ratio is usually 3.0 to 7 times, preferably 3.5 to 6 times. Subsequently, heat treatment is performed at a temperature of 180 to 270 ° C. under tension or under relaxation within 30% to obtain a biaxially oriented film. In the above-described stretching, a method in which stretching in one direction is performed in two or more stages can be employed. In that case, it is preferable to carry out so that the draw ratios in the two directions finally fall within the above ranges.

Also, the simultaneous biaxial stretching method can be adopted for the production of the polyester film. The simultaneous biaxial stretching method is a method in which the unstretched sheet is usually stretched and oriented simultaneously in the machine direction and the width direction in a state where the temperature is controlled at 70 to 120 ° C, preferably 80 to 110 ° C. The area magnification is 4 to 50 times, preferably 7 to 35 times, and more preferably 10 to 25 times. Subsequently, heat treatment is performed at a temperature of 170 to 250 ° C. under tension or under relaxation within 30% to obtain a stretched oriented film. With respect to the simultaneous biaxial stretching apparatus that employs the above-described stretching method, conventionally known stretching methods such as a screw method, a pantograph method, and a linear drive method can be employed.

Furthermore, a so-called coating stretching method (in-line coating) for treating the film surface during the above-described polyester film stretching step can be performed. When a coating layer is provided on a polyester film by a coating stretching method, coating can be performed simultaneously with stretching and the thickness of the coating layer can be reduced according to the stretching ratio, producing a film suitable as a polyester film. it can.

Next, the coating layer will be described.
The polyester film has at least one binder resin selected from polyester resin, acrylic resin, and urethane resin, melamine resin, oxazoline group-containing resin, and isocyanate compound to improve adhesion to the barrier layer. A coating layer containing at least one kind of crosslinking agent selected from the inside is formed.

The polyester resin is defined as a linear polyester having a dicarboxylic acid component and a glycol component as constituent components. Dicarboxylic acid components include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4-diphenyldicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, adipic acid, sebacic acid, phenylindanedicarboxylic acid, A dimer acid etc. can be illustrated. Two or more of these components can be used. In addition to these components, a small proportion of unsaturated polybasic acids such as maleic acid, fumaric acid, itaconic acid and the like, and hydroxycarboxylic acids such as p-hydroxybenzoic acid and p- (β-hydroxyethoxy) benzoic acid, etc. Can be used. The proportion of the unsaturated polybasic acid component or the hydroxycarboxylic acid component is at most 10 mol%, preferably 5 mol% or less.

Examples of the glycol component include ethylene glycol, 1,4-butanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, xylylene glycol, dimethylolpropionic acid. Glycerin, trimethylolpropane, poly (ethyleneoxy) glycol, poly (tetramethyleneoxy) glycol, an alkylene oxide adduct of bisphenol A, an alkylene oxide adduct of hydrogenated bisphenol A, and the like. Two or more of these can be used.

Among such polyol components, ethylene glycol and bisphenol A ethylene oxide adducts and propylene oxide adducts and 1,4-butanediol are preferred, and ethylene glycol and bisphenol A ethylene oxide adducts and propylene oxide adducts are more preferred.

Moreover, in the coating layer which comprises the sealing film in this invention, in order to make water dispersion or water-solubilization easy, it may contain at least 1 or more types of polyester resin which has a sulfonic acid (salt) group. preferable.

Examples of the polyester resin having a sulfonic acid (salt) group include 5-sodium sulfoisophthalic acid, 5-ammonium sulfoisophthalic acid, 4-sodium sulfoisophthalic acid, 4-methylammonium sulfoisophthalic acid, 2-sodium sulfoisophthalic acid, Preferable examples include sulfonic acid alkali metal salt compounds or sulfonic acid amine salt compounds such as 5-potassium sulfoisophthalic acid, 4-potassium sulfoisophthalic acid, 2-potassium sulfoisophthalic acid, and sodium sulfosuccinic acid.

In the polyester resin, the glass transition temperature (hereinafter sometimes abbreviated as Tg) is preferably 40 ° C. or higher, more preferably 60 ° C. or higher. When Tg is less than 40 ° C., for the purpose of improving adhesiveness, when the coating thickness of the coating layer is increased, problems such as easy blocking may occur.

An acrylic resin is a polymer composed of a polymerizable monomer having a carbon-carbon double bond, as typified by acrylic and methacrylic monomers. These may be either a homopolymer or a copolymer. Moreover, the copolymer of these polymers and other polymers (for example, polyester, polyurethane, etc.) is also included. For example, a block copolymer or a graft copolymer. Furthermore, a polymer (in some cases, a mixture of polymers) obtained by polymerizing a polymerizable monomer having a carbon-carbon double bond in a polyester solution or a polyester dispersion is also included. Similarly, a polymer (in some cases, a mixture of polymers) obtained by polymerizing a polymerizable monomer having a carbon-carbon double bond in a polyurethane solution or polyurethane dispersion is also included. Similarly, a polymer (in some cases, a polymer mixture) obtained by polymerizing a polymerizable monomer having a carbon-carbon double bond in another polymer solution or dispersion is also included.

The polymerizable monomer having a carbon-carbon double bond is not particularly limited, but representative compounds such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid, and citraconic acid. Various carboxyl group-containing monomers and their salts; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, monobutylhydroxyl fumarate, monobutylhydroxy Various hydroxyl-containing monomers such as itaconate; various (meth) acrylic such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, lauryl (meth) acrylate Acid esters; (meth) a Riruamido, various nitrogen-containing vinyl monomers such as diacetone acrylamide, N- methylol acrylamide or (meth) acrylonitrile. Further, in combination with these, polymerizable monomers as shown below can be copolymerized. That is, various styrene derivatives such as styrene, α-methylstyrene, divinylbenzene and vinyltoluene, various vinyl esters such as vinyl acetate and vinyl propionate; γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, Various silicon-containing polymerizable monomers such as methacryloyl silicon macromer; phosphorus-containing vinyl monomers; vinyl chloride, biliden chloride, vinyl fluoride, vinylidene fluoride, trifluorochloroethylene, tetrafluoroethylene, chlorotrifluoroethylene And various vinyl halides such as hexafluoropropylene; and various conjugated dienes such as butadiene.

In the acrylic resin, the glass transition temperature (hereinafter sometimes abbreviated as Tg) is preferably 40 ° C. or higher, more preferably 60 ° C. or higher. When Tg is less than 40 ° C., for the purpose of improving adhesiveness, when the coating thickness of the coating layer is increased, problems such as easy blocking may occur.

The urethane resin is preferably a urethane resin having a polycarbonate structure. The urethane resin having a polycarbonate structure refers to a urethane resin in which one of the polyols, which are main components of the urethane resin, is a polycarbonate polyol.

Polycarbonate polyols are obtained from a polyhydric alcohol and a carbonate compound by a dealcoholization reaction. The polyhydric alcohols include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, trimethylolpropane, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, , 5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, , 10-decanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, and the like. Examples of the carbonate compound include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, and ethylene carbonate. Examples of the polycarbonate-based polyols obtained from these reactions include poly (1,6-hexylene) carbonate, poly (3- And methyl-1,5-pentylene) carbonate.

Examples of the polyisocyanates constituting the urethane resin having a polycarbonate structure include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, methylene diphenyl diisocyanate, phenylene diisocyanate, naphthalene diisocyanate, and tolidine diisocyanate, α, α, α ′, Aliphatic diisocyanates having an aromatic ring such as α'-tetramethylxylylene diisocyanate, methylene diisocyanate, propylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate, hexamethylene diisocyanate and other aliphatic diisocyanates, cyclohexane diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate , Mechi Nbisu (4-cyclohexyl isocyanate), dicyclohexylmethane diisocyanate, alicyclic diisocyanates such as isopropylidene dicyclohexyl diisocyanates. These may be used alone or in combination. Among the above isocyanates, aliphatic isocyanates or alicyclic isocyanates are more preferable than aromatic isocyanates from the viewpoint of improving adhesion to the active energy ray-curable coating material and preventing yellowing due to ultraviolet rays.

A chain extender may be used when synthesizing the urethane resin, and the chain extender is not particularly limited as long as it has two or more active groups that react with an isocyanate group. Alternatively, a chain extender having two amino groups can be mainly used.

Examples of the chain extender having two hydroxyl groups include aliphatic glycols such as ethylene glycol, propylene glycol, butanediol and pentanediol, aromatic glycols such as xylylene glycol and bishydroxyethoxybenzene, neopentyl glycol and neopentyl. Examples include glycols such as ester glycols such as glycol hydroxypivalate. Examples of the chain extender having two amino groups include aromatic diamines such as tolylenediamine, xylylenediamine, diphenylmethanediamine, ethylenediamine, propylenediamine, hexanediamine, 2,2-dimethyl-1,3- Propanediamine, 2-methyl-1,5-pentanediamine, trimethylhexanediamine, 2-butyl-2-ethyl-1,5-pentanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10- Aliphatic diamines such as decane diamine, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, dicyclohexylmethanediamine, isopropylidine cyclohexyl-4,4′-diamine, 1,4-diaminocyclohexane, 1 , 3-Bisaminomethylcyclohexane Alicyclic diamines such as isophorone diamine.

Urethane resin may use a solvent as a medium, but preferably uses water as a medium. In order to disperse or dissolve the urethane resin in water, there are a forced emulsification type using an emulsifier, a self-emulsification type in which a hydrophilic group is introduced into the urethane resin, and a water-soluble type. In particular, a self-emulsification type in which an ionic group is introduced into the skeleton of a urethane resin to form an ionomer is preferable because of excellent storage stability of the liquid and water resistance, transparency, and adhesion of the resulting coating layer.

In addition, examples of the ionic group to be introduced include various groups such as a carboxyl group, a sulfonic acid, a phosphoric acid, a phosphonic acid, a quaternary ammonium salt, and the carboxyl group is preferable. As a method for introducing a carboxyl group into a urethane resin, various methods can be taken in each stage of the polymerization reaction. For example, there are a method of using a carboxyl group-containing resin as a copolymer component during prepolymer synthesis, and a method of using a component having a carboxyl group as one component such as polyol, polyisocyanate, and chain extender. In particular, a method in which a desired amount of carboxyl groups is introduced using a carboxyl group-containing diol depending on the amount of this component charged is preferred. For example, dimethylolpropionic acid, dimethylolbutanoic acid, bis- (2-hydroxyethyl) propionic acid, bis- (2-hydroxyethyl) butanoic acid, and the like are copolymerized with a diol used for polymerization of a urethane resin. Can do. The carboxyl group is preferably in the form of a salt neutralized with ammonia, amine, alkali metal, inorganic alkali or the like. Particularly preferred are ammonia, trimethylamine and triethylamine.

The urethane resin having a polycarbonate structure has a glass transition point (hereinafter sometimes referred to as Tg) of preferably 0 ° C. or lower, more preferably −15 ° C. or lower, and further preferably −30 ° C. or lower. When Tg is higher than 0 ° C., easy adhesion may be insufficient. Tg said here refers to the temperature which created the dry film | membrane of the urethane resin and measured using the differential scanning calorimeter (DSC).

The oxazoline compound is a compound having an oxazoline group in the molecule, and is particularly preferably a polymer containing an oxazoline group, and can be prepared by polymerization of an addition polymerizable oxazoline group-containing monomer alone or with another monomer. Addition-polymerizable oxazoline group-containing monomers include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, Examples thereof include 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, and the like, and one or a mixture of two or more thereof can be used. Of these, 2-isopropenyl-2-oxazoline is preferred because it is easily available industrially. The other monomer is not particularly limited as long as it is a monomer copolymerizable with an addition polymerizable oxazoline group-containing monomer. For example, alkyl (meth) acrylate (alkyl groups include methyl, ethyl, n-propyl, isopropyl, (Meth) acrylic acid esters such as n-butyl group, isobutyl group, t-butyl group, 2-ethylhexyl group, cyclohexyl group); acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, styrene Unsaturated carboxylic acids such as sulfonic acid and its salts (sodium salt, potassium salt, ammonium salt, tertiary amine salt, etc.); Unsaturated nitriles such as acrylonitrile, methacrylonitrile; (meth) acrylamide, N-alkyl ( (Meth) acrylamide, N, N-dialkyl (meth) acrylamide, Examples of the alkyl group include unsaturated amides such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, 2-ethylhexyl, cyclohexyl, etc .; vinyl acetate Vinyl esters such as vinyl propionate; vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; α-olefins such as ethylene and propylene; halogen-containing α, β-unsaturated monomers such as vinyl chloride and vinylidene chloride; styrene, An α, β-unsaturated aromatic monomer such as α-methylstyrene can be used, and one or more of these monomers can be used.

The content of the oxazoline group contained in the oxazoline compound is usually 0.5 to 10 mmol / g, preferably 1 to 9 mmol / g, more preferably 3 to 8 mmol / g, still more preferably 4 to 6 mmol in terms of the amount of the oxazoline group. / G. Use in the above range is preferable for improving the coating strength.

The melamine resin is not particularly limited, but melamine, a methylolated melamine derivative obtained by condensing melamine and formaldehyde, a compound partially or completely etherified by reacting a methylolated melamine with a lower alcohol, and These mixtures can be used.

Further, the melamine resin may be either a monomer or a condensate composed of a dimer or higher multimer, or a mixture thereof. As the lower alcohol used for the etherification, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butanol, isobutanol and the like can be preferably used. The functional group has an imino group, a methylol group, or an alkoxymethyl group such as a methoxymethyl group or a butoxymethyl group in one molecule, and an imino group type methylated melamine, a methylol group type melamine, or a methylol group type methylated group. Melamine, fully alkyl methylated melamine and the like can be used. Of these, methylolated melamine is most preferred. Furthermore, an acidic catalyst such as p-toluenesulfonic acid can be used in combination for the purpose of promoting the thermosetting of the melamine resin.

The isocyanate compound is a compound having an isocyanate derivative structure typified by isocyanate or blocked isocyanate. Examples of isocyanates include aromatic isocyanates such as tolylene diisocyanate, xylylene diisocyanate, methylene diphenyl diisocyanate, phenylene diisocyanate, and naphthalene diisocyanate, and aromatic rings such as α, α, α ′, α′-tetramethylxylylene diisocyanate. Aliphatic isocyanates such as aliphatic isocyanate, methylene diisocyanate, propylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate, methylene bis (4-cyclohexyl isocyanate), isopropylidene dicyclohexyl diisocyanate Ne Alicyclic isocyanates such as bets are exemplified. Reaction products of these isocyanates with various polymers and compounds may be used. Further, polymers and derivatives such as burettes, isocyanurates, uretdiones, and carbodiimide modified products of these isocyanates are also included. These may be used alone or in combination. Among the above isocyanates, aliphatic isocyanates or alicyclic isocyanates are more preferable than aromatic isocyanates in order to avoid yellowing due to ultraviolet rays.

When used in the state of blocked isocyanate, the blocking agent includes, for example, bisulfites, phenolic compounds such as phenol, cresol, and ethylphenol, and alcohols such as propylene glycol monomethyl ether, ethylene glycol, benzyl alcohol, methanol, and ethanol. Compounds, active methylene compounds such as dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate and acetylacetone, mercaptan compounds such as butyl mercaptan and dodecyl mercaptan, lactam compounds such as ε-caprolactam and δ-valerolactam , Amine compounds such as diphenylaniline, aniline, ethyleneimine, acetanilide, acid amide compounds of acetic acid amide, formaldehyde, acetal Examples include oxime compounds such as dooxime, acetone oxime, methyl ethyl ketone oxime, and cyclohexanone oxime, and these may be used alone or in combination of two or more.

In addition, the isocyanate compound in the present invention may be used alone or as a mixture or combination with various polymers. In the sense of improving the dispersibility and crosslinkability of the isocyanate-based compound, a mixture or a combined product with a polyester resin or a polyurethane resin may be used.

The ratio of each component in the coating layer is as follows.
The proportion of the polyester resin is usually 10 to 80% by weight, preferably 20 to 60% by weight, the proportion of the acrylic resin is usually 10 to 60% by weight, preferably 20 to 50% by weight, and the proportion of the urethane resin is usually 10%. -80 wt%, preferably 20-60 wt%, the proportion of oxazoline compound is usually 20-80 wt%, preferably 40-80 wt%, and the proportion of melamine resin is usually 6-80 wt%, preferably 10 The proportion of the isocyanate compound is generally 6 to 80% by weight, preferably 10 to 60% by weight.

The coating layer is formed by applying a coating solution and drying, and the coating amount (after drying) is usually 0.005 to 1 g / m ² , preferably 0.005 from the viewpoint of coating properties. The range is from -0.5 g / m ² , more preferably from 0.01 to 0.2 g / m ² . When the coating amount (after drying) is less than 0.005 g / m ² , the coating property may be less stable and it may be difficult to obtain a uniform coating film. On the other hand, when the coating is thicker than 1 g / m ² , the coating film adhesion and curability of the coating layer itself may be lowered.

Conventionally known coating methods such as reverse gravure coating, direct gravure coating, roll coating, die coating, bar coating, curtain coating and the like can be used as a method for applying the coating solution to the polyester film. As for the coating method, there is an example described in “Coating Method” Tsuji Shoten published by Yuji Harasaki in 1979.

A coating layer such as an antistatic layer or an oligomer precipitation preventing layer may be provided on the film surface not provided with a coating layer as long as the gist of the present invention is not impaired.

Further, the polyester film may be subjected to surface treatment such as corona treatment or plasma treatment in advance.

Next, the barrier layer will be described.
The barrier layer is laminated for the purpose of imparting barrier properties to the polyester film. As a material for the barrier layer, the barrier property is at a desired level. In the present invention, the water vapor permeability measured according to the JIS-K7129B method is 0.01 g / m under measurement conditions of a temperature of 40 ° C. and a humidity of 90% RH. There is no particular limitation as long as it can be ² / day or less.

Examples of the material for the barrier layer include silicon compounds such as polysilazane compounds, polycarbosilane compounds, polysilane compounds, polyorganosiloxane compounds, and tetraorganosilane compounds, silicon oxide, silicon oxynitride, aluminum oxide, aluminum oxynitride, and magnesium oxide. Inorganic oxides such as zinc oxide, indium oxide, and tin oxide, inorganic nitrides such as silicon nitride and aluminum nitride, inorganic oxynitrides such as silicon oxynitride, and metals such as aluminum, magnesium, zinc, and tin It is done. These can be used individually by 1 type or in combination of 2 or more types.

The thickness of the barrier layer is usually 1 nm to 10 μm, preferably 10 nm to 5 μm, more preferably 20 to 500 nm, and particularly preferably 50 to 200 nm. If the thickness of the barrier layer is less than 1 nm, the barrier effect may be insufficient. On the other hand, when it exceeds 10 μm, it is in a saturated state in terms of performance, and it is difficult to expect a barrier effect any more.

The barrier layer may have a single layer structure or a plurality of layers composed of two or more layers.

The method for forming the barrier layer can be a conventionally known method depending on the material constituting the barrier layer, and can be appropriately selected depending on the purpose. For example, a method in which the barrier layer material is formed on a polyester film by vapor deposition, sputtering, ion plating, thermal CVD, plasma CVD, or the like, or a solution in which the barrier layer material is dissolved in an organic solvent Is applied to a polyester film, and plasma ion implantation is performed on the obtained coating film. Examples of ions implanted by plasma ion implantation include rare gases such as argon, helium, neon, krypton, and xenon, ions such as fluorocarbon, hydrogen, nitrogen, oxygen, carbon dioxide, chlorine, fluorine, and sulfur; gold, Examples include ions of metals such as silver, copper, platinum, nickel, palladium, chromium, titanium, molybdenum, niobium, tantalum, tungsten, and aluminum.

Next, the protective layer will be described.
By coating the protective layer on the barrier layer, the coating liquid for forming the protective layer penetrates evenly into the minute defects existing in the barrier layer, and the defective portion of the barrier layer can be repaired by thermosetting. Become. In addition, by covering the barrier layer with a protective layer, it is rubbed or scraped due to contact with the guide roller for conveyance during the processing step, and also protects the barrier layer from the organic solvent used in the manufacturing step, It is also possible to maintain barrier properties.

Hereinafter, embodiments in which an organic compound containing at least one metal element selected from aluminum, titanium, and zirconium is contained in the protective layer will be exemplified.

Specific examples of the organic compound having an aluminum element include aluminum tris (acetylacetonate), aluminum monoacetylacetonate bis (ethylacetoacetate), aluminum-di-n-butoxide-monoethylacetoacetate, aluminum-di -Iso-propoxide-monomethyl acetoacetate and the like are exemplified.

Specific examples of the organic compound having titanium element include titanium orthoesters such as tetranormal butyl titanate, tetraisopropyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, tetramethyl titanate; titanium acetylacetonate, Examples thereof include titanium chelates such as titanium tetraacetylacetonate, polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate, titanium triethanolamate, and titanium ethylacetoacetate.

Specific examples of the organic compound having a zirconium element include, for example, zirconium acetate, zirconium normal propylate, zirconium normal butyrate, zirconium tetraacetylacetonate, zirconium monoacetylacetonate, zirconium bisacetylacetonate and the like.

Among them, an organic compound having a chelate structure is preferable with respect to an organic compound containing a metal element selected from aluminum and zirconium, particularly in terms of good adhesion performance. In addition, it is specifically described in “Crosslinking agent handbook” (Yamashita Shinzo, Kaneko Tosuke ed., Taiseisha Co., Ltd., 1990 edition).

The protective layer is preferably used in combination with an organosilicon compound represented by the following general formula (1) in order to protect the barrier layer and improve the adhesion to the adhesive layer.

The organosilicon compound constituting the protective layer in the present invention is represented by the general formula (1): Si (X) _d (Y) _e (R ¹ ) _f [wherein X is an epoxy group, a mercapto group, a (meth) acryloyl group, An organic group having at least one selected from an alkenyl group, a haloalkyl group and an amino group, R ¹ is a monovalent hydrocarbon group and has 1 to 10 carbon atoms, Y is a hydrolyzable group, d is an integer of 1 or 2, e is an integer of 2 or 3, f is an integer of 0 or 1, and d + e + f = 4. It is preferable to use a type represented by

The organosilicon compound represented by the general formula (1) has two hydrolyzable groups Y (D unit source) or three (T units) capable of forming a siloxane bond by hydrolysis / condensation reaction. Source) can be used.

In the general formula (1), the monovalent hydrocarbon group R ¹ has 1 to 10 carbon atoms, and is particularly preferably a methyl group, an ethyl group, or a propyl group.

In the general formula (1), as the hydrolyzable group Y, conventionally known ones can be used, and the following can be exemplified. Methoxy group, ethoxy group, butoxy group, isopropenoxy group, acetoxy group, butanoxime group, amino group and the like. These hydrolyzable groups may be used alone or in combination. The use of a methoxy group or an ethoxy group is particularly preferable because it can impart good storage stability to the coating material and has suitable hydrolyzability.

Specific examples of the organosilicon compound include vinyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, 5-hexenyltrimethoxysilane, p-styryltrimethoxysilane, tri Examples include fluoropropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldiisopropenoxysilane, and the like.

In the protective layer, a catalyst may be used in combination for the purpose of promoting hydrolysis / condensation reaction. Specific examples include organic acids such as acetic acid, butyric acid, maleic acid and citric acid, inorganic acids such as hydrochloric acid, nitric acid, phosphoric acid and sulfuric acid, basic compounds such as triethylamine, tetrabutyl titanate, dibutyltin dilaurate and dibutyltin. Organic metal salts such as diacetate, dibutyltin dioctate, dibutyltin diolate, diphenyltin diacetate, dibutyltin oxide, dibutyltin dimethoxide, dibutylbis (triethoxysiloxy) tin, dibutyltin benzylmalate, etc., fluorine such as KF and NH4F Examples thereof include element-containing compounds. The above catalysts may be used alone or in combination of two or more. Among them, organometallic salts are particularly preferable from the viewpoint that the coating film durability is good, and it is more preferable to use a tin catalyst because the catalytic activity is sustainable for a long time.

As another embodiment of the protective layer, a case where a urethane resin is contained in the protective layer is exemplified.
The urethane resin is a resin obtained by reacting an isocyanate compound with a diol or a polyol compound. Examples of the isocyanate compound include aromatic polyisocyanate, aliphatic polyisocyanate, alicyclic polyisocyanate, and aliphatic polyisocyanate, and a diisocyanate compound is usually used. Examples of the aromatic diisocyanate include tolylene diisocyanate (2,4- or 2,6-tolylene diisocyanate or a mixture thereof) (TDI), phenylene diisocyanate (m-, p-phenylene diisocyanate or a mixture thereof), 4,4 '-Diphenyl diisocyanate, 1,5-naphthalene diisocyanate (NDI), diphenylmethane diisocyanate (4,4'-, 2,4'-, or 2,2'-diphenylmethane diisocyanate or mixtures thereof) (MDI) 4,4′-toluidine diisocyanate (TODI), 4,4′-diphenyl ether diisocyanate, and the like. Examples of the araliphatic diisocyanate include xylylene diisocyanate (1,3- or 1,4-xylylene diisocyanate or a mixture thereof) (XDI), tetramethylxylylene diisocyanate (1,3- or 1,4- Tetramethylxylylene diisocyanate or a mixture thereof (TMXDI), ω, ω′-diisocyanate-1,4-diethylbenzene, and the like. Examples of the alicyclic diisocyanate include 1,3-cyclopentene diisocyanate, cyclohexane diisocyanate (1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate), 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (iso Holo isocyanate, IPDI), methylene bis (cyclohexyl isocyanate) (4,4′-, 2,4′- or 2,2′-methylene bis (cyclohexyl isocyanate)) (hydrogenated MDI), methylcyclohexane diisocyanate (methyl-2, 4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate), bis (isocyanate methyl) cyclohexane (1,3- or 1,4-bis (isocyanate) Tomechiru) cyclohexane or mixtures thereof) (hydrogenated XDI) and the like. Examples of the aliphatic diisocyanate include trimethylene diisocyanate, 1,2-propylene diisocyanate, butylene diisocyanate (tetramethylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate), Examples include hexamethylene diisocyanate, pentamethylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, and 2,6-diisocyanate methyl caffeate.

As the diol or polyol component constituting the urethane resin, alkylene glycol can be suitably used from the viewpoint of gas barrier properties. Examples of the alkylene glycol include carbon numbers such as ethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, pentanediol, hexanediol, neopentylglycol, heptanediol, and octanediol. A low molecular weight glycol such as an alkylene glycol having a linear or branched chain of 2 to 10 and a (poly) oxyalkylene glycol having 2 to 4 carbon atoms can be used. These diol components can be used alone or in combination of two or more. Further, if necessary, aromatic diols such as bisphenol A, bisbidoxetyl terephthalate, catechol, resorcin, hydroquinone, 1,3- or 1,4-xylylenediol, hydrogenated biswaenol A, hydrogenated xylylenediol A low molecular weight diol component such as cycloaliphatic diol such as cyclohexanediol or cyclohexane may be used in combination. Furthermore, if necessary, a tri- or higher functional polyol component, for example, a polyol component such as glycerin, trimethylolethane, or trimethylolpropane can be used in combination. The polyol component preferably contains a polyol component having 2 to 8 carbon atoms.

Furthermore, the protective layer may contain inorganic particles for the purpose of improving adhesion and slipperiness, as long as the gist of the present invention is not impaired. Specific examples include silica, alumina, kaolin, calcium carbonate, oxidation Examples include titanium and barium salts.

In addition, an antifoaming agent, a coating property improver, a thickener, an organic lubricant, organic polymer particles, an antioxidant, a UV absorber foaming agent, a dye, and the like may be contained as necessary.

In the range not exceeding the gist of the present invention, only one type of organic solvent may be used for the purpose of improving dispersibility, improving film forming property, etc., and two or more types may be used as appropriate.

The coating amount of the protective layer (after drying) is usually in the range of 0.005 to 1 g / m ² , preferably 0.005 to 0.5 g / m ² . When the coating amount (after drying) is less than 0.005 g / m ² , the uniformity of the coating thickness may be insufficient, and the protective function as a protective layer may be insufficient. On the other hand, when the coating is applied in excess of 1 g / m ² , problems such as a decrease in slipperiness may occur.

The protective layer composed of the above composition has good durability and excellent adhesion to the adhesive layer. Depending on the product configuration, it may be possible to directly bond with the quantum dot-containing resin sheet without an adhesive layer.

In the sealing film thus obtained, the total light transmittance is preferably 86% or more, more preferably 89% or more. When the total light transmittance is less than 86%, when used as a sealing film for a quantum dot-containing resin sheet, electronic paper, organic EL, etc., the transparency of the device is lowered and the visibility may be inferior.

It is an essential requirement that the water vapor permeability of the sealing film of the present invention is 0.01 g / m ² / day or less. Preferably, 0.005 g / m ² / day or less is preferable. In particular, as a sealing film for an electronic member, 0.005 g / m ² / day or less is desired, and when the range is exceeded, moisture gradually enters the device during long-term use of the device, and the device deteriorates. It tends to happen easily.

Next, a quantum dot-containing resin sheet will be described as a counterpart to which the sealing film in the present invention is bonded.

The resin sheet layer containing quantum dots (sometimes abbreviated as quantum dot layer) may contain a plurality of quantum dots and resins. A quantum dot means a semiconductor particle of a predetermined size having a quantum confinement effect. It is preferable to use a quantum dot having a diameter generally in the range of 1 to 10 nm.

When the quantum dot absorbs light from the excitation source and reaches an energy excited state, it emits energy corresponding to the energy band gap of the quantum dot. Therefore, by adjusting the size of the quantum dots or the composition of the substance, the energy band gap can be adjusted, and energy of various levels of wavelength bands can be obtained.

For example, a red color is emitted when the quantum dot size is 55 to 65 mm, a green color is emitted when the quantum dot size is 40 to 50 mm, and a blue color is emitted when the quantum dot size is 20 to 35 mm. The yellow color has an intermediate size between the quantum dots emitting red and the quantum dots emitting green. It can be seen that the size of the quantum dot gradually changes from about 65 mm to about 20 mm by changing the spectrum depending on the wavelength of light from red to blue, and there may be a slight difference in this value.

Therefore, various colors including red, green, and blue can be easily obtained from the quantum dots by a quantum size effect. Therefore, it is also possible to create colors that emit light at respective wavelengths, and it is also possible to generate and realize white or various colors by mixing red, green, and blue.

For example, when the light emitted from the light source is blue light, the quantum dot layer may include red quantum dots and green quantum dots. The red quantum dots convert part of blue light into red light having a wavelength range of 620 to 750 nm, and the green quantum dots convert part of blue light into green light having a wavelength range of 495 to 570 nm. To do. And the blue light which is not converted into red light and green light permeate | transmits a quantum dot layer as it is. Therefore, in the quantum dot layer, blue light, red light, and green light are emitted to the upper surface, and these lights are mixed to generate white light.

The quantum dots may be synthesized by a chemical wet method. The chemical wet method is a method of growing particles by putting a precursor substance in an organic solvent. Examples of the quantum dots include II-VI group compounds such as CdSe, CdTe, CdS, ZnSe, ZnTe, ZnS, HgTe, and HgS.

The quantum dots may have a core / shell structure. Here, the core includes any one material selected from the group consisting of CdSe, CdTe, CdS, ZnSe, ZnTe, ZnS, HgTe, and HgS, and the shell also includes CdSe, CdTe, CdS, ZnSe, Any one substance selected from the group consisting of ZnTe, ZnS, HgTe, and HgS is included. Furthermore, a III-V group compound such as InP may be used.

The organic ligand substituted on the surface of the quantum dot includes pyridine, mercaptoalcohol, thiol, phosphine, phosphine oxide, and the like, and plays a role of stabilizing the unstable quantum dot after synthesis. Examples of commercially available quantum dots include various quantum dots manufactured by SIGMA-ALDRICH.

Also, for the resin containing quantum dots, it is preferable to use a substance that does not absorb the wavelength of light emitted mainly from the light source. Specifically, epoxy, silicone, acrylic polymer, glass, carbonate polymer, or a mixture thereof may be used. When the resin has elasticity, it can also contribute to improving the durability of the liquid crystal display device against external impact.

On the other hand, the method of forming the quantum dot layer is as follows.

Quantum dot-containing resin sheets may be formed by adding a plurality of quantum dots to the resin and applying the resin to the top of the color filter layer using a spin coating method or a printing method.

Further, the quantum dot resin sheet may be formed by molding and curing a resin to which quantum dots are added.

Furthermore, a quantum dot layer may be formed by injecting an organic solution, dispersing a plurality of quantum dots therein, and curing the organic solution. The organic solution may include at least one of toluene, chloroform, and ethanol. Here, the organic solution does not absorb blue wavelengths. In this case, since the reaction between the quantum dot ligand and the organic solution does not occur, there is an advantage that the lifetime and efficiency of the quantum dot layer are increased.

Quantum dot-containing resin sheet has a laminate structure in which a sealing film is bonded through an adhesive layer.

The above adhesive layer will be described below.
The adhesive layer means a layer composed of an adhesive material, and conventionally known materials such as an acrylic adhesive and a silicone adhesive can be used. In pasting, a conventionally known pasting method can be adopted.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist. The measuring method used in the present invention is as follows.

(1) Measurement of intrinsic viscosity (dl / g) of polyester:
1 g of polyester from which other polymer components and pigments incompatible with polyester were removed was precisely weighed, 100 ml of a mixed solvent of phenol / tetrachloroethane = 50/50 (weight ratio) was added and dissolved, and measurement was performed at 30 ° C.

(2) Measurement of average particle diameter (d50: μm):
The value of 50% of integration (weight basis) in the equivalent spherical distribution measured using a centrifugal sedimentation type particle size distribution measuring apparatus (SA-CP3 type manufactured by Shimadzu Corporation) was defined as the average particle diameter.

(3) Glass transition temperature (Tg) measurement of polyester resin:
Using a DSC-II type measuring device manufactured by PerkinElmer, Inc., the sample was heated at a rate of temperature increase of 10 ° C./min under a nitrogen stream, and the baseline start temperature of the baseline was defined as Tg.

(4) Barrier layer thickness:
A sample film piece was cut into a size of 1 mm × 10 mm and embedded in an epoxy resin for an electron microscope. This was fixed to a sample holder of an ultramicrotome, and a cross-sectional thin section parallel to the short side of the embedded sample piece was produced. Next, in a portion where the thin film of this section is not significantly damaged, a transmission electron microscope (manufactured by JEOL, JEM-2010) is used to photograph at an acceleration voltage of 200 kV and a bright field at an observation magnification of 10,000 times. The film thickness was determined from the photograph taken.

(5) Refractive index measurement of protective layer and polyester film:
According to JIS K 7142-1996 5.1 (Method A), the refractive index was measured with an Abbe refractometer using sodium D line as a light source.

(6) Refractive index measurement of coating layer and barrier layer:
For the coating layer or barrier layer formed on a silicon wafer or quartz glass with a coater, using a high-speed spectrometer M-2000 (manufactured by JA Woollam), the polarization state change of the reflected light of the coating layer or barrier layer Were measured at an incident angle of 60 degrees, 65 degrees, and 70 degrees, and the refractive index at a wavelength of 550 nm was calculated by analysis software WVASE32.

(7) Evaluation of transparency of sealing film:
In accordance with JIS-K-7136, the total light transmittance of the measurement sealing film was measured with a haze meter “HM-150” manufactured by Murakami Color Research Laboratory Co., Ltd.
(Criteria)
A: Total light transmittance 89% or more (good, no problem)
B: Total light transmittance of 86% or more and less than 89% (although there is no problem, it may be difficult to apply to high-end display devices)

(8) Water vapor transmission rate:
JISK7129 using a water vapor transmission rate measuring device (model name, “Permatran” (registered trademark) W3 / 31) manufactured by MOCON, USA, under the conditions of a temperature of 40 ° C. and a humidity of 90% RH. It was measured based on the B method (infrared sensor method) described in (2000 version). Two test pieces were cut out from one sample, each test piece was measured once, and the average value of the two measured values was taken as the value of the water vapor transmission rate of the sample.

(9) Adhesiveness to the adhesive layer:
Using each of the laminates obtained in Examples and Comparative Examples, the feeling of peeling when peeling one sealing film from the laminate was determined according to the following criteria.
(Criteria)
A: The sealing film and the quantum dot-containing resin sheet are firmly bonded and difficult to peel off. (Practical, no problem level)
B: The sealing film and the quantum dot-containing resin sheet can be peeled off. (Practical problem level)

(10) Evaluation of luminance unevenness of laminated body (practical property substitution evaluation):
On the light diffusion film of the TFT liquid crystal module (Sharp Co., Ltd. 192GC00 type), each sealing film obtained in Example (9) and Comparative Example and a quantum dot-containing resin sheet were pasted. The combined laminate was sandwiched, the LED light source was made to emit light by applying 9.75 V, and brightness unevenness was determined using the following criteria.
(Criteria)
A: State in which luminance unevenness is not recognized.
B: Although there is some luminance unevenness, there is no practical problem.
C: A state in which luminance unevenness is clearly present and is a problem in practical use.

(11) Overall evaluation:
Using the sealing films produced in Examples and Comparative Examples, overall evaluation was performed according to the following criteria for each evaluation item of transparency, barrier properties, adhesion to the adhesive layer, and luminance unevenness.
<Criteria>
A: Transparency, barrier properties, adhesion to the adhesive layer, and luminance unevenness are all judged as A. (Practical, no problem level)
B: At least one of transparency, barrier properties, adhesion to the pressure-sensitive adhesive layer, and luminance unevenness includes B determination. (Practical level that may cause problems)
C: At least one of transparency, barrier property, adhesion to the adhesive layer, and luminance unevenness includes C determination. (Practical problem level)

The polyester used in the examples and comparative examples was prepared as follows.
<Manufacture of polyester>

Production Example 1 (Polyester A1)
100 parts of dimethyl terephthalate, 60 parts of ethylene glycol and 0.09 part of magnesium acetate tetrahydrate are placed in a reactor, the temperature is raised by heating, methanol is distilled off, transesterification is performed, and 4 hours are required from the start of the reaction. The temperature was raised to 230 ° C. to substantially complete the transesterification reaction. Next, after adding 0.04 part of ethylene glycol slurry ethyl acid phosphate and 0.03 part of antimony trioxide, the temperature reached 280 ° C. and the pressure reached 15 mmHg in 100 minutes. It was 0.3 mmHg. After 4 hours, the system was returned to normal pressure to obtain polyester A1 having an intrinsic viscosity of 0.61 (dl / g).

Production Example 2 (Polyester A2)
In the method for producing polyester (A1), polyester (A1) was used except that after adding ethyl acid phosphate, silica particles having an average particle diameter of 2.3 μm were added so that the content with respect to polyester was 0.2% by weight. ) Was used to obtain polyester A2 having an intrinsic viscosity of 0.62 (dl / g).

Example 1 (Manufacture of sealing film F1)
The raw materials blended at a ratio of 85% and 15% respectively for polyesters A1 and A2 were used as surface layer materials, and 100% of the raw materials were used as intermediate layer materials and supplied to two extruders with vents at 290 ° C. After melt-extrusion, an amorphous film having a thickness of about 1500 μm was obtained by cooling and solidifying on a cooling roll having a surface temperature set to 40 ° C. using an electrostatic application adhesion method. This film was stretched 3.5 times in the machine direction at 85 ° C. Thereafter, a coating solution having the following coating layer composition was applied on both sides so that the coating thickness (after drying) was 0.05 g / m ² , the film was guided to a tenter, and 3.8 times in the lateral direction at 100 ° C. It was stretched and heat treated at 210 ° C. to obtain a polyester film F1 provided with a coating layer having a thickness of 100 μm (thickness ratio = 2.5 μm / 95 μm / 2.5 μm).

Moreover, the following was used as a composition contained in the coating solution.

<Production conditions for (aqueous acrylic resin)>
A mixture of 40 parts by weight of ethyl acrylate, 30 parts by weight of methyl methacrylate, 20 parts by weight of methacrylic acid and 10 parts by weight of glycidyl methacrylate was solution-polymerized in ethyl alcohol, and heated while adding water after polymerization to remove ethyl alcohol. The pH was adjusted to 7.5 with aqueous ammonia to obtain an aqueous acrylic resin aqueous paint.

<Production conditions for (aqueous polyurethane resin)>
First, a polyester polyol comprising 664 parts by weight of terephthalic acid, 631 parts by weight of isophthalic acid, 472 parts by weight of 1,4-butanediol, and 447 parts by weight of neopentyl glycol was obtained. Next, 321 parts by weight of adipic acid and 268 parts by weight of dimethylolpropionic acid were added to the obtained polyester polyol to obtain a pendant carboxyl group-containing polyester polyol A. Further, 160 parts by weight of hexamethylene diisocyanate was added to 1880 parts by weight of the polyester polyol A to obtain an aqueous polyurethane resin aqueous coating material.

<Water-based polyester resin>
Tg = 63 ° C
Acid component: terephthalic acid 50 mol%
Isophthalic acid 48mol%
2-Na sulfoisophthalic acid 2 mol%
Diol component: Ethylene glycol 50 mol%
Neopentyl glycol 50 mol%

<Isocyanate compounds>
Active methylene block polyisocyanate synthesized by the following method:
1000 parts by weight of hexamethylene diisocyanate was stirred at 60 ° C., and 0.1 part by weight of tetramethylammonium capryate was added as a catalyst. Four hours later, 0.2 parts by weight of phosphoric acid was added to stop the reaction, and an isocyanurate type polyisocyanate composition was obtained. 100 parts by weight of the obtained isocyanurate-type polyisocyanate composition, 42.3 parts by weight of methoxypolyethylene glycol having a number average molecular weight of 400, and 29.5 parts by weight of propylene glycol monomethyl ether acetate were charged and maintained at 80 ° C. for 7 hours. Thereafter, the temperature of the reaction solution was maintained at 60 ° C., 35.8 parts by weight of methyl isobutanoyl acetate, 32.2 parts by weight of diethyl malonate, and 0.88 parts by weight of 28% methanol solution of sodium methoxide were added and maintained for 4 hours. . Block polyisocyanate obtained by adding 58.9 parts by weight of n-butanol, maintaining the reaction solution temperature at 80 ° C. for 2 hours, and then adding 0.86 parts by weight of 2-ethylhexyl acid phosphate.

(Coating layer composition)
*: Oxazoline group-containing polymer ("Epocross WS-500" manufactured by Nippon Shokubai Co., Ltd.)
Oxazoline group amount 4.5 mmol / g) 0% by weight,
・: Aqueous acrylic resin 0% by weight,
・: 45% by weight of water-based urethane resin
・: Melamine resin 30% by weight
(Beccamine “J101” manufactured by DIC, a crosslinkable resin of alkylol melamine / urea copolymer)
*: 20% by weight of aqueous polyester resin,
*: Isocyanate-based compound 0% by weight
*: 5% by weight of colloidal silica (average particle size 70 nm)
The coating solution was diluted with ion exchange water to prepare a coating solution having a solid content concentration of 2% by weight.

<Formation of barrier layer 1>
An active energy ray curable resin composed of the following active energy ray curable resin composition is applied to the coating layer surface of the obtained coated film with a # 16 wire bar, dried at 80 ° C. for 1 minute to remove the solvent, and then irradiated with ultraviolet rays. The barrier layer 1 having a thickness (after drying) of 5 μm was provided by irradiating ultraviolet rays from the machine with a metal halide lamp 120 w / cm so that the integrated light amount was 180 mJ / cm ² .
<Active energy ray curable resin composition>
A mixed coating solution of 72 parts by weight of dipentaerythritol acrylate, 18 parts by weight of 2-hydroxy-3-phenoxypropyl acrylate, 1 part by weight of a photopolymerization initiator (Irgacure 651, manufactured by Ciba Specialty Chemicals), and 200 parts by weight of methyl ethyl ketone.

<Formation of barrier layer 2>
The following barrier layer 2 was laminated on the barrier layer 1. Specifically, it was carried out after confirming that the water pressure in the vacuum chamber before sputtering was 1 × 10 ⁻⁴ Pa. As sputtering conditions, Al—Si (composition ratio Al: Si = 5: 5, manufactured by High Purity Chemical) was used as a target, and DC power of 3 W / cm ² was applied. Moreover, Ar gas was flowed, it was made into the atmosphere of 0.4 Pa, and it formed into a film using DC magnetron sputtering method. At this time, the magnetic field strength was 600 gauss. The center roll temperature was set to 0 ° C., and the oxygen flow rate was controlled using a Speedflow manufactured by Gencoa so that the discharge voltage during sputtering was constant. At this time, the discharge voltage is set to 50% when the discharge voltage when only Ar gas is supplied is 100%, and when the discharge voltage is 50% when Ar gas and O ₂ gas are supplied at 50 sccm. did. As described above, the barrier layer 2 having a thickness of 40 nm and a refractive index of 1.52 was deposited.

<Protective layer 1 formation>
Organic compound having aluminum element (A1): 19.5% by weight
Aluminum tris (acetylacetonate)
Organosilicon compound (B1): 80% by weight
γ-Glycidoxypropyltrimethoxysilane catalyst (C1): 0.5% by weight
Dibutyltin dilaurate
The coating agent was diluted with a toluene / MEK mixed solvent (mixing ratio was 1: 1) to obtain 4% by weight.

Thereafter, the protective layer 1 composed of the above coating composition is applied on the barrier layer 2 by a reverse gravure coating method so that the coating amount (after drying) is 0.1 g / m ^2, and heat treatment is performed at 120 ° C. for 30 seconds. After that, a sealing film was obtained.

Next, the obtained sealing film was bonded to both surfaces of the quantum dot-containing resin sheet by the following procedure to obtain a laminate.

<Preparation of coating liquid for forming quantum dot resin sheet>
Using a polyethylene container with a capacity of 300 ml, 40% by weight of “OE-6630A / B” (manufactured by Toray Dow Corning Co., Ltd., refractive index 1.53) as a silicone resin, and “CdSe / ZnS480” (SIGMA- ALDRICH: Blue 480 nm), “CdSe / ZnS 530” (SIGMA-ALDRICH: Green 530 nm), “CdSe / ZnS 560” (SIGMA-ALDRICH: Yellow 560 nm) were mixed at a ratio of 20% by weight. Thereafter, using a planetary stirring and defoaming apparatus “Mazerustar (registered trademark)” KK-400 (manufactured by Kurabo Industries), stirring and defoaming were carried out at 1000 rpm for 20 minutes to obtain a quantum dot-containing resin sheet preparation solution.

<Quantum dot resin sheet formation>
Using a slit die coater, a sheet-forming resin solution is applied on a polyester film (Diafoil T100 type manufactured by Mitsubishi Plastics Co., Ltd .: 100 μm), heated at 130 ° C. for 5 minutes, and dried to obtain a film thickness (after drying). A quantum dot resin sheet having a thickness of 50 μm was obtained. The obtained quantum dot resin sheet was uniformly applied on the base film, pinholes were not seen, and the film thickness uniformity was good.

<Formation of laminate>
“SD4580” (silicone adhesive manufactured by Toray Dow Corning) was applied to both surfaces of the quantum dot resin sheet and dried by heating at 100 ° C. for 5 minutes to obtain an adhesive layer having a thickness of 25 μm. Furthermore, on the adhesive layer, as the cover film, the sealing film was heat-laminated at 100 ° C. for 3 minutes so that the protective layer surface was bonded to the adhesive layer surface.

Example 2 to Example 12
In Example 1, it manufactured like Example 1 except having changed application layer composition and polyester film base material thickness as shown in the following Table 1 and Table 2, and obtained the sealing film.
Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Examples 13-15
In Example 1, it manufactured similarly to Example 1 except having changed the structure of the barrier layer into the following barrier layer 2, and obtained the sealing film. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.
<Formation of barrier layer 3>
A gas barrier layer made of aluminum oxide was formed. At this time, it was carried out after confirming that the water pressure in the vacuum chamber before sputtering was 1 × 10 ⁻⁴ Pa. As sputtering conditions, Al (manufactured by Technofine) was used as a target, and DC power of 3 W / cm ² was applied. Moreover, Ar gas was flowed, it was made into the atmosphere of 0.4 Pa, and it formed into a film using DC magnetron sputtering method. At this time, the magnetic field strength was 600 gauss. The center roll temperature was set to 0 ° C., and the oxygen flow rate was controlled using a Speedflo manufactured by Gencoa so that the discharge voltage during sputtering was constant. At this time, the discharge voltage was set to 50% when the discharge voltage when only Ar gas was supplied was 100%, and when the discharge voltage was 50% when Ar gas and O2 gas were supplied at 50 sccm. . As described above, the barrier layer 2 having a film thickness of 32 nm and a refractive index of 1.61 was formed on the coating layer.
In the obtained sealing film, since the difference in refractive index between the barrier layer 2 (refractive index 1.61) and the protective layer (refractive index: 1.43) was large, the result was slightly inferior in transparency.

Examples 16-18
A sealing film was obtained in the same manner as in Example 1 except that the protective layer composition was changed to protective layer 2 in Example 1 and the adhesive layer was changed to an acrylic adhesive layer. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.
<Protection layer 2 formation>
Main agent: WPB-341 (Mitsui Chemicals)
Curing agent: WD-725 (Mitsui Chemicals)

A coating solution for a protective layer having a solid content concentration of 10% by weight was prepared using a mixing ratio of main agent / curing agent = 100 / 3.75 (weight ratio), ethyl acetate: toluene mixed solvent (mixing ratio is 1: 1). .

(Acrylic adhesive layer composition)
A solution of an acrylic copolymer having a weight average molecular weight of 600,000 (polystyrene equivalent) by copolymerizing butyl acrylate (100 parts by weight, acrylic acid 6 parts by weight) in ethyl acetate by a conventional method (solid content 30% by weight) ) To 100 parts by weight (solid content) of the acrylic copolymer, 6 parts by weight of tetrad C (manufactured by Mitsubishi Gas Chemical) as an epoxy crosslinking agent was added to obtain an acrylic adhesive layer composition.

Example 19
A sealing film was obtained in the same manner as in Example 1 except that the substrate thickness was changed to 50 μm in Example 1. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Example 20
In Example 1, it manufactured similarly to Example 1 except having changed the barrier layer structure into 1 layer structure only of the barrier layer 1, and obtained the sealing film. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Example 21
In Example 1, it manufactured like Example 1 except changing a barrier layer composition into one layer composition only of barrier layer 2, and obtained a sealing film. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Example 22
A sealing film was obtained in the same manner as in Example 1 except that the raw material composition of the polyester film was changed in Example 1. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Example 23
In Example 1, it manufactured similarly to Example 1 except not providing an application layer in the surface opposite to the surface which provides a barrier layer, and obtained the sealing film. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Example 24
In Example 1, except that the type of the adhesive layer is changed to the acrylic adhesive layer described in Example 16, it is heated and dried at 100 ° C. for 5 minutes in the same manner as in Example 1 to obtain an acrylic adhesive layer having a thickness of 25 μm. Then, the sealing film and the quantum dot containing resin sheet were bonded together, and the laminated body was obtained.

Comparative Example 1
In Example 1, it manufactured similarly to Example 1 except having changed the structure of the application layer into the application layer 5, and obtained the sealing film. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Comparative Example 2
In Example 1, it manufactured similarly to Example 1 except having changed the structure of the application layer into the application layer 10, and obtained the sealing film. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Comparative Example 3
In Example 1, it manufactured similarly to Example 1 except having changed the structure of the application layer into the application layer 15, and obtained the sealing film. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Comparative Example 4
In Example 1, it manufactured similarly to Example 1 except not providing an application layer, and obtained the sealing film. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Comparative Example 5
In Example 1, it manufactured similarly to Example 1 except not providing a barrier layer, and obtained the sealing film. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Comparative Example 6
In Example 1, it manufactured similarly to Example 1 except not providing a protective layer, and obtained the sealing film. Then, the sealing film and the quantum dot containing resin sheet were bonded together through the adhesion layer, and the laminated body was obtained.

Tables 1 to 5 show the properties of the sealing films obtained in the above examples and comparative examples.

 

 

 

 

 

 

The sealing film for electronic members of the present invention is particularly excellent in transparency, water vapor barrier properties and adhesiveness with an adhesive layer, and is an electron such as a quantum dot-containing resin sheet, electronic paper, and organic EL, which requires high water vapor barrier properties. It is suitable as a sealing film for members, and its industrial value is high.

DESCRIPTION OF SYMBOLS 10: Laminated body 11: Quantum dot containing resin sheet 12: 1st polyester film 13: 1st application layer 14: 1st barrier layer 15: 1st protective layer 22: 2nd polyester film 23: 2nd application layer 24: 1st 2 barrier layer 25: 2nd protective layer 31: 1st sealing film 32: 2nd sealing film 41: 1st adhesion layer 42: 2nd adhesion layer

Claims (7)

1. A sealing film in which a coating layer, a barrier layer, and a protective layer are sequentially laminated on one side of a polyester film, and the coating layer includes at least one binder resin selected from a polyester resin, an acrylic resin, and a urethane resin. And at least one crosslinking agent selected from oxazoline compounds, melamine resins, and isocyanate compounds, and measured under measurement conditions of a temperature of 40 ° C. and a humidity of 90% RH according to JIS-K7129B method. The sealing film for electronic members, wherein the sealing film has a water vapor permeability of 0.01 g / m ² / day or less.
2. In the coating layer, the proportion of polyester resin is 10 to 80% by weight, the proportion of acrylic resin is 10 to 60% by weight, the proportion of urethane resin is 10 to 80% by weight, the proportion of oxazoline compound is 20 to 80% by weight, melamine resin The sealing film for an electronic member according to claim 1, wherein the proportion of is 8 to 80% by weight and the proportion of the isocyanate compound is 6 to 80% by weight.
3. The sealing film for electronic members according to claim 1 or 2, wherein the barrier layer comprises at least two layers.
4. The sealing film for electronic members according to any one of claims 1 to 3, wherein the protective layer contains a urethane resin.
5. The electronic member sealing film according to any one of claims 1 to 4, wherein the electronic member is a quantum dot-containing resin sheet.
6. 6. A film laminate, wherein the electronic member sealing film according to claim 1 is bonded to both surfaces of the quantum dot-containing resin sheet via an adhesive layer.
7. The film laminate according to claim 6, wherein the adhesive layer is acrylic or silicone.

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