JP2013039784A - Polyester type adhesive and sheet-like laminate using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that the polyester type adhesive has excellent adhesiveness and electric insulation to a polyester film, and used for an adhesive layer of a sheet-like laminate for electric insulation such as a solar battery back side protective sheet; meanwhile, a request for hydrolysis resistance has been severer in the applications, and improvement of the hydrolysis resistance has been requested not only for a film base material, but also for the polyester type adhesive.SOLUTION: The problem is solved by providing the hydrolysis resistance in the polyester itself, and at the same time, by performing the recombination and self-repair by the additive to be reacted with the polyester terminal group cut by the hydrolysis. In other words, the problem is solved by using the polyester mainly comprising aromatic dicarboxylic acid components, with the carbon number being ≥3, while ester groups being separated from each other, cut molecular chains, and the specific binder for recombination and repair.

Description

The present invention relates to a polyester adhesive having excellent hydrolysis resistance and a laminate including a film, a metal foil, a metal plate, a metal thin film, a ceramic thin film and the like using the polyester adhesive as an adhesive layer.

Polyester resins mainly composed of polyethylene terephthalate and polybutylene terephthalate have excellent mechanical properties, heat resistance, electrical insulation, chemical resistance, safety,
As is well known, it is produced and used in large quantities all over the world as fibers, films and molding resins from the viewpoint of molding processability. Polyester resins inherently have hydrolyzable problems, but in recent years, they have been used under severe wet heat conditions such as solar cell back surface protection sheets, and the demand for hydrolysis resistance is severe again. It has become. In the case of a film, it is rare that it is used alone, and it is used by adhering to other materials with an adhesive, but a polyester-based adhesive that has excellent adhesion to a polyester film is used with a polyester film. There are many cases. Accordingly, there is an increasing demand for improvement in hydrolysis resistance for polyester adhesives as well.

Since the hydrolysis reaction of polyester is known to be accelerated in an acidic or alkaline environment, the carboxyl end group of polyester and the phosphorus compound added to suppress thermal decomposition during polymerization also make the system acidic, Polyesters containing a carboxyl group content of a specified amount or less and a specified amount of a phosphorus compound have been proposed (Patent Documents 1 and 2).
There is also an idea of adding a buffering agent such as inorganic phosphate to suppress proton release and suppress hydrolysis (Patent Documents 3, 4, and 5).
The idea of adding an epoxy compound, a carbodiimide compound, or an oxazoline compound that seals by reacting with a carboxyl group has been proposed for a long time (Patent Documents 6, 7, 8,
9)
High-molecular-weight polyesters obtained by solid-phase polymerization and polyesters with reduced oligomers, which are thought to lead to less carboxyl groups, have also been proposed as hydrolysis-resistant polyesters. (Patent Documents 10 and 11)
The chemical structure of the polyester itself is also related to the hydrolyzability, and the smaller the proportion of the ester group in the polyester, the less likely hydrolysis occurs.
1,8-octanediol and / or 1,9-nonanediol (Patent Document 12),
Polyester obtained from 3-methylpentane-diacid (patent document 13), 3,7-dimethyl-heptanediol (patent document 14), dimer fatty acid or glycol obtained by reducing dimer fatty acid (patent document 15), etc. Proposed.

JP-A-8-3428 JP 2011-6659 A JP 2007-277548 A JP 2008-7750 A JP 2011-89090 A JP 54-6051 A Japanese Patent Laid-Open No. 46-5389 Japanese Patent Application Laid-Open No. 8-113699 JP-A-6-287442 JP 2002-26354 A Japanese Patent Laid-Open No. 2002-100788 JP-A-63-182330 Japanese Patent Laid-Open No. 10-130377 JP 11-236436 A JP 2007-320218 A

As described above, a technology for improving hydrolysis degradation of polyester has been developed in each field in which a polyester resin is used. As the above-mentioned solar cell back surface protection sheet, a durability test for maintaining its performance for 20 years or more requires 85 hours at 85 ° C./85% relative humidity. There is a problem that the durability is influenced by delamination. Similar problems are printed circuit board members,
It is also a common problem in the fields of electrical insulation members such as capacitors and flat cables, engine protection members, building members such as window-laminated films, and laminated steel sheets for outdoor use.

In view of the above-described problems, an object of the present invention is to provide a polyester-based adhesive that can be used in the industrial field and can withstand long-term wet heat deterioration, and a sheet-like laminate using the polyester-based adhesive.

Means for achieving the above objectives are:
(1) 50 to 100 mol% of all ester bonds in the main chain forming the polyester
An ester bond derived from an aromatic carboxylic acid, a polyester having 3 or more carbon atoms in a group present between the ester bond in the main chain and having a number average molecular weight of 5000 to 35000 When the polyester having a fusing temperature between 50 to 200 ° C. is A, a bifunctional or higher isocyanate compound or / and a blocked isocyanate compound is B, and a bifunctional or higher epoxy compound is C, A / B
(Weight ratio) is 100/0 to 70/30, and A / C (weight ratio) is 99.9 / 0.1.
A film or / and a metal foil or / and a metal plate or / and a metal thin film or / or a polyester-based adhesive comprising a resin composition containing 70/30 as an essential component and an adhesive layer obtained therefrom And a sheet-like laminate of ceramic thin films,
(2) The sheet-like laminate according to (1), wherein the polyester-based adhesive according to (1) includes a reaction accelerator for an epoxy compound,
(3) The film constituting the laminate of (1) and (2) is a polyester film, a polycarbonate film, a fluororesin film, an acrylic resin film, a polyolefin film, an olefin, and an oxygen-containing monomer. Copolymer resin film, metal foil that also constitutes the laminate, copper foil, aluminum foil or their thin film,
The sheet-like laminate according to (1) and (2) above, wherein the ceramic thin film constituting the steel foil or plate and the laminate is silicon oxide and / or aluminum oxide,
(4) The sheet-like laminates of (1), (2) and (3), wherein the sheet-like laminates of (1), (2) and (3) are used for a back surface protective sheet of a solar cell module. body,
(5) The sheet-like laminates of (1), (2) and (3) are used for circuit materials, flat cable materials or bus bar materials, (1) and (2)
And (3) a sheet-like laminate,
(6) The sheet-like laminate of (1), (2) and (3), wherein the laminate of (1), (2) and (3) is used for a laminated steel plate.

The sheet-like laminate including the polyester-based adhesive of the present invention and the adhesive layer obtained by using the polyester-based adhesive is a polyester-based adhesive excellent in hydrolysis resistance, and is protected from the back surface of a solar cell that requires wet heat durability. Use durability and reliability of the sheet, circuit member, electrical insulating member, electrical wiring member, and laminated steel plate member can be improved as compared with the conventional product.

Hereinafter, embodiments of the present invention will be described in detail.
The first feature of the present invention is that hydrolysis resistance is imparted to the polyester skeleton structure itself. That is, in the polyester used in the present invention, 50 to 100 mol% of all ester bonds in the main chain forming the polyester are aromatic carboxylic acid-derived ester bonds, and the ester bond and the ester bond in the main chain. Is a polyester having 3 or more carbon atoms contained in a group present in the range, having a number average molecular weight of 5000 to 35000 and a fusing temperature between 50 and 200 ° C. .

Aromatic carboxylic acid components can increase cohesion between molecules and are less likely to be attacked by water than aliphatic carboxylic acid components. This simultaneously imparts chemical resistance, but makes it difficult to dissolve in the solvent used in the adhesive and limits its use. In addition, the aromatic carboxylic acid component increases the glass transition point and melting point of the resulting polyester resin and imparts rigidity to the resin. These characteristics may be incompatible with those required for adhesives used for films, sheets and the like. Therefore, it is preferable that 50 to 100 mol% of all ester bonds in the main chain forming the polyester resin of the present invention are aromatic carboxylic acid-derived ester bonds. The number of carbons contained in the group present between the ester bond and the ester bond in the main chain is 3 or more. This is because when the number of carbons contained in the group existing in the meantime is less than 3,
This is based on the finding that hydrolysis of the polyester group is likely to occur.
The number average molecular weight of the polyester used for this invention is 5000-35000, Preferably it is 8000-25000. If it is less than 5000, the adhesive layer after cross-linking with polyfunctional isocyanate or polyfunctional epoxy compound becomes hard, and the adhesion becomes poor.
If it exceeds 35000, the solution viscosity and the melt viscosity become high, and the bonding process becomes difficult, which is not preferable. The polyester of the present invention is a polyester having a fusing temperature between 50 and 200 ° C. The polyester of the present invention melts at a certain temperature or more to become liquid and adheres to the substrate. It means that the temperature at which this tackiness is exhibited is in the range of 50 ° C to 200 ° C. In other words, by applying a moderate pressure at this temperature, the initial process of “wetting the adherend surface” can be satisfied. That is, it shows that the fusion property is developed at this temperature. When this temperature is less than 50 ° C., handling in the process from polymerization to preparation of the adhesive is difficult, and tackiness after coating on a film or foil becomes a problem.
When pasting above 200 ° C, the plastic film may be deformed.
It is not preferable. The acid value (mgKOH / g resin) of the polyester of the present invention is preferably 3 or less. This is because hydrolysis is accelerated during storage of the resin and before the carboxyl group is sealed with a crosslinking agent.

Examples of the aromatic dicarboxylic acid forming the polyester of the present invention in the form of acid include terephthalic acid, isophthalic acid, orthophthalic acid, 4,4'-biphenyldicarboxylic acid, 1,
Examples include 5-naphthalenedicarboxylic acid and 2,6-naphthalenedicarboxylic acid. Examples of the aliphatic dicarboxylic acid and alicyclic dicarboxylic acid that can be used to form the polyester of the present invention in the form of acid include adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, decamethylene dicarboxylic acid, Examples thereof include dimer acids, hydrogenated products thereof, and aliphatic dicarboxylic acids having 5 or more carbon atoms such as 1,4-cyclohexanedicarboxylic acid. Further, within the range where the polyester exhibits fusibility, trimellitic acid,
Trifunctional or higher functional carboxylic acids such as pyromellitic acid, benzophenone tetracarboxylic acid, and diphenylsulfone tetracarboxylic acid can also be used.

Examples of glycols forming the polyester of the present invention include 1,3-propanediol, 1,2-propanediol, 2-methyl-1,3-propanediol, 2,2-
Dimethyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol 1,10-decanediol, 1,12-dodecanediol, aliphatic glycols such as 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, ethylene oxide adducts of bisphenol-A, polyethylene glycol, polytetramethylene glycol And ether glycol. In addition, trifunctional or higher functional alcohols such as glycerol and pentaerythritol can be used within the range in which the polyester exhibits fusibility.

Examples of oxycarboxylic acids and cyclic ester monomers that can be used to form the polyester of the present invention in the form of cyclic esters include γ-butyrolactone and ε-caprolactone.

The polyester of the present invention can be produced using ordinary polyester synthesis methods and equipment.
In the transesterification method, transesterification catalysts such as zinc acetate, manganese acetate, calcium acetate, and titanium tetra-n-butoxide, and heavy metals such as germanium oxide, antimony oxide, potassium oxalate titanate, and titanium tetra-n-butoxide are used. The condensation catalyst is used in an amount of 0.005 to 0.05 mol% based on the total acid components. In the esterification method, the above polycondensation catalyst is used. Moreover, phosphorus compounds, such as phosphate ester and phosphite, can also be added as a heat stabilizer during polycondensation. The addition amount of the phosphorus compound as the stabilizer is preferably 5 to 200 ppm as the phosphorus element.

The polyester-based adhesive in the present invention is an adhesive whose main resin component is polyester, and the polyester may be a blend of two or more polyesters or a block polyester. Moreover, the polyester previously reacted with the isocyanate compound and epoxy compound which can react with polyester terminal groups, such as a hydroxyl group and a carboxyl group, may be sufficient.

A second feature of the present invention is that when the polyester of the present invention is A, a bifunctional or higher isocyanate compound or / and a blocked isocyanate compound is B, and a bifunctional or higher epoxy compound is C, A / B (weight) Ratio) from 100/0 to 70/30, A / C
A resin composition containing (weight ratio) at a ratio of 99.9 / 0.1 to 70/30 is an essential component. The bifunctional or higher isocyanate compound or / and the blocked isocyanate compound B and the bifunctional or higher epoxy compound C both function as a crosslinking agent for the polyester of the present invention, and block a new carboxyl group generated by hydrolysis. In addition to inhibiting its catalytic action, it has the function of recombining and repairing the cut polyester chains. In addition, isocyanate compounds and epoxy compounds are effective in improving adhesion to metals and ceramics, and reactions between isocyanate compounds and epoxy compounds also occur. For these reasons, compared to the polyester end group equivalent,
It is designed to include an excess of B or C equivalent to a functional group equivalent of 2 times or more in total. From the above hydrolysis resistance viewpoint and the demand as an adhesive, A / B (weight ratio) is 100/0 to 70/30.
It is. That is, when an isocyanate compound or / and a blocked isocyanate compound are not used, when the adhesive of the present invention is mainly applied and formed by a melting method, the isocyanate compound can be melted even if a block type is used. This is because it is difficult to control processing conditions and reaction conditions with isocyanate independently.
This is because if it is less than 70/30, the original adhesiveness of the polyester is impaired.
Similarly, A / C (weight ratio) from the above hydrolysis resistance viewpoint and the requirement as an adhesive is:
99.9 / 0.1 to 70/30. That is, when this ratio exceeds 99.9 / 0.1, the amount of epoxy groups that can react with the carboxyl group generated from the polyester is not reached, and when it is less than 70/30, the original adhesiveness of the polyester is impaired. Because. Similar to isocyanate compounds and epoxy compounds, other compounds that react with hydroxyl groups or carboxyl groups, for example, carbodiimide compounds and oxazoline compounds may be used in combination.

Examples of the bifunctional or higher functional isocyanate compound used in the present invention include hexamethylene diisocyanate in aliphatic isocyanate or alicyclic isocyanate,
Examples thereof include isophorone diisocyanate, xylylene diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, and adduct type, burette type and isocyanurate type trifunctional isocyanates derived from these diisocyanates. For aromatic isocyanates, 2,4-tolylene diisocyanate, 2,6-
Tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1.5
-Naphthalene diisocyanate and adduct type, burette type and isocyanurate type trifunctional isocyanates derived from these diisocyanates can be mentioned.
In the polyester-based adhesive of the present invention, the isocyanate to be used can be appropriately selected depending on the end use, but in applications where the adhesive is required to have heat resistance, a tri- or higher functional isocyanate is usually used as a crosslinking agent. In applications where heat resistance and light resistance are required, a tri- or higher functional aliphatic isocyanate is preferably used as a crosslinking agent.

The blocked isocyanate compound used in the present invention is a reaction product of an isocyanate compound and a blocking agent as described above. Examples of the blocking agent include formamide oxime,
Oximes such as acetamide oxime, acetoxime and methyl ethyl ketoxime, active methylenes such as dimethyl malonate, diethyl malonate, methyl acetoacetate and acetylacetone, phenols such as phenol and cresol, lactams such as ε-caprolactam, 2- Examples include alcohols such as ethylhexanol and amines such as 2,3-dimethylpyrazole. Of these, oximes, lactams, and amine blocking agents are preferred.
The separation temperature of the blocked isocyanate is preferably 90 to 200 ° C, more preferably
90-150 ° C. When it is lower than 90 ° C, it is separated in the drying process of the adhesive solvent,
This is because the adhesiveness may be impaired, and when it exceeds 200 ° C., the laminated plastic film may be deteriorated.

Two or more types of the isocyanate compound or / and blocked isocyanate compound of the present invention can be used in combination. When using an isocyanate compound and a block isocyanate compound together, it is one of the preferable aspects of this invention to use the block isocyanate compound of 20 to 100% of the total weight of both. This is to achieve both the curability of the adhesive and the stability over time.

Examples of bifunctional or higher functional epoxy compounds used in the present invention include polyglycidyl ethers of aliphatic polyols such as 1,6-hexanediol, neopentyl glycol, polyalkylene glycol, sorbitol, glycerol, trimethylolpropane, and cyclohexanedi. Polyglycidyl ethers of alicyclic polyglycols such as methanol, 2,2-bis- (p-hydroxycyclohexyl) propane, terephthalic acid,
Isophthalic acid, trimellitic acid, 1,6-cyclohexanedicarboxylic acid, sebacic acid,
Polyglycidyl esters of aromatic, alicyclic and aliphatic polycarboxylic acids such as adipic acid, resorcinol, bis- (p-hydroxyphenyl) methane, 2,2-bis- (p
An epoxy derived from a polyglycidyl ether of a polyhydric phenol such as -hydroxyphenyl) propane or tris- (p-hydroxyphenyl) methane, a hydrocarbon-based diene such as butadiene, α-pinene or cyclooctadiene; Examples thereof include polyglycidyl derivatives of amines such as N-diglycidylaniline and N, N-diglycidyltoluidine, triglycidyl isocyanurate, orthocresol type epoxy, phenol novolac type epoxy and the like. Moreover, the epoxy compound which made these epoxy compounds react with phosphoric acid or its derivative (s) may be sufficient. These epoxy compounds can be used alone or in combination of two or more.

In order to seal the carboxyl group generated by the hydrolysis of the polyester and to recombine and repair the cut polyester chains, an accelerator for the reaction between the hydroxyl group, carboxyl group and isocyanate group or epoxy group is used as an adhesive in advance. Mixing is one of the preferred embodiments of the present invention. As an isocyanate group reaction accelerator, dibutyltin di (2
-Ethylhexanoate), dibutyltin dilaurate, dibutyltin oxide, dioctyltin oxide and other tin compounds, 1,8-diazabicyclo [5,4,0] undec-7-ene (commonly known as DBU), triethylamine, tributylamine, And tertiary amines such as The compounding amount of these catalysts is based on the total weight of the isocyanate compound or / and the blocked isocyanate B and the polyester A.
A range of 0.01% to 2% by weight is preferred. As an epoxy group reaction accelerator,
Examples include imidazole derivatives such as 1,2-dimethylimidazole and 1-benzyl-2-methylimidazole, phosphorus compounds such as triphenylphosphine and triphenylphosphite, and quaternary ammonium salts such as tetra-n-butylammonium bromide. I can do it. The blending amount of these reaction accelerators is preferably in the range of 0.01% by weight to 2% by weight with respect to the total weight of the epoxy compound C and polyester A.

The polyester-based adhesive of the present invention includes benzophenone-based, benzotriazole-based, triazine-based ultraviolet absorbers, hindered amine-based light stabilizers, hindered phenol-based, phosphorus-based, sulfur-based, tocopherol-based antioxidants, etc. Organic compounds, inorganic compounds, metal oxides and the like can be appropriately added as flame retardants, viscosity modifiers, coating film reinforcing agents, color pigments and the like.

The polyester adhesive of the present invention has a dry thickness of 1 μm to 50 μm, usually 2 μm to
15 μm. Coating on the substrate can be carried out using a coating machine such as a bar coater, a gravure coater, a roll coater, a die coater or a comma coater as a solution or dispersion dissolved or dispersed in a solvent or / and water. Also, extrusion coating using a melt extrusion die is possible.
Solvents used include ketones such as acetone, methyl ethyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, ethers such as tetrahydrofuran and dioxane, aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethylacetamide, Examples include aprotic polar solvents such as N-methylpyrrolidone-2. These solvents can be used alone or in admixture of two or more.

The adhesive of the present invention is applied to the surface of any one or both of the substrates to be laminated and dried as described above, and then a hot press machine at 50 ° C. to 200 ° C., 1 kg / cm 2 to 30 kg / cm 2 Or it can stick together with a heating roll. Thereafter, the curing reaction can be carried out at 20 to 100 ° C. for 1 hour to 1 week.

The laminated base material of the present invention includes polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamides such as polypentamethylene amide, polydecamethylene amide and polyundecamethylene amide, polyolefins such as polyethylene and polypropylene, and polymethyl methacrylate. , Acrylics such as polyacrylonitrile, vinyl acetates such as polyvinyl acetate and polyvinyl butyral, polyvinyl fluoride,
Polyvinylidene fluoride, poly (ethylene-tetrafluoroethylene), poly (tetrafluoroethylene-hexafluoropropylene), poly (chlorotrifluoroethylene), tetrafluoroethylene-hydroxybutyl vinyl ether copolymer, chlorotrifluoroethylene-hydroxy Butyl vinyl ether copolymer, vinylidene fluoride-hydroxybutyl vinyl ether copolymer, fluorine type, polymethylsiloxane, polyphenylsiloxane, poly (methyl-phenylsiloxane) and other silicone type, other polyimide type, polyether Homopolymers, copolymerized polymers, polymer blends, polymers such as ketones, polysulfones, polycarbonates, polyacetals, poly (2,5-dimethylphenylene ether) Alloy, a film made of cross-linked product, copper, aluminum, steel, silicon oxide, aluminum oxide, thin film made of such as glass, foil, and the like plate. Further, the base material layer can be formed directly or without laminating the adhesive layer on the surface of the base material. The direct formation of the base material layer can be performed by solution coating, melt coating, vapor deposition, sputtering, ion plating, chemical vapor deposition (CVD), wet plating, or the like.
Examples of the thickness of these base materials include a thin film of 5 nm to 500 nm, a film of 1 μm to 500 μm, a foil, a coating layer, and a plate of 0.5 mm to 5 mm.

As these thin films, foils, and films, ordinary industrial products can be used. Two or more of these films, thin films, foils, and plates may be combined and laminated. For example, a laminated film of two or more kinds of resins, a laminated film of a film and a metal thin film or a metal oxide thin film, a dissimilar metal laminated foil, and the like. In addition, the surface of a film, a coating layer, a thin film, a foil, a plate, or the like may be chemically, physically, mechanically, or electrically treated. There are corona treatment, plasma treatment, chemical etching in the case of a film, oxidation treatment, roughening treatment, plating, alloying in the case of a metal foil or plate.

If the structure of the sheet-like laminated body using the polyester-type adhesive of this invention is illustrated, the two-layer laminated body by which the adhesive layer of this invention was laminated | stacked on the single side | surface of metal foil, such as polyester films and copper foil Further, a three-layer laminate in which a film or a metal foil is laminated on the adhesive layer,
As a four-layer laminate in which an adhesive layer is laminated on the laminate, a laminate of five layers, six layers, and n layers can be given (n is a positive integer up to 20 in general).

Specific examples include a two-layer laminate of polyethylene terephthalate film / adhesive layer, a three-layer laminate of polyethylene terephthalate film / adhesive layer / release sheet, and a three-layer laminate of polyethylene terephthalate film / adhesive layer / electrolytic copper foil. 4 consisting of polyvinylidene fluoride film / adhesive layer / polyethylene terephthalate film / adhesive layer
5 layer laminate consisting of layer laminate, polyvinylidene fluoride film / adhesive layer / polyethylene terephthalate film / adhesive layer / polyvinylidene fluoride film, polyvinylidene fluoride film / adhesive layer / polyethylene terephthalate film / adhesive layer / polyethylene 5-layer laminate composed of a polyethylene film, comprising a polyvinylidene fluoride film / adhesive layer / silicon oxide-aluminum oxide composite oxide laminated polyethylene terephthalate film / adhesive layer / polyethylene terephthalate film / adhesive layer / polyvinylidene fluoride film An 8-layer laminate can be used.

EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to these Examples.
The raw materials for producing polyester and the raw materials for preparing the adhesive used in the following examples and comparative examples and their abbreviations are shown.
Raw materials for polyester production are TPA: terephthalic acid, IPA: isophthalic acid, O
PA: orthophthalic acid, AA: adipic acid, SA: sebacic acid, EG: ethylene glycol, 2-MPD: 2-methyl-1,3-propanediol, NPG: neopentyl glycol, 1,4-BD: 1 , 4-butanediol, 1,5-PD: 1,5-pentanediol, 1,6-HD: 1,6-hexanediol, 1,4-CHD: 1,4
-Cyclohexanedimethanol.
The raw materials for preparing the adhesive are: Duranate TPA-100: Asahi Kasei Chemical's hexamethylene isocyanate (isocyanurate type) trifunctional isocyanate, Epicoat 827: Japan Epoxy Resin's epoxy resin (bisphenol A type),
Carbodilite V-05: a polycarbodiimide resin manufactured by Nisshinbo Co., Ltd.

Experimental methods and measurement methods carried out in Examples and Comparative Examples are shown below.
(1) Polyester synthesis stirrer, rectification tube, cooling tube, nitrogen gas introduction tube, thermometer, dicarboxylic acid component such as terephthalic acid, isophthalic acid, etc. in a stainless steel reaction kettle equipped with 2- Methyl
A glycol component such as 1,3-propanediol and 1,6-hexanediol, and 0.04 mol% of germanium dioxide as a polycondensation catalyst with respect to the total acid component are charged, and the temperature at the top of the rectifying tube is adjusted to 100 under a nitrogen stream. The esterification reaction is carried out by heating at 160 to 240 ° C. while maintaining the temperature at or below ℃. Triethyl phosphate (100 ppm as P) was added to this reaction mixture as a stabilizer, and after stirring for 5 minutes, the temperature was gradually raised and the pressure was reduced.
It is set to 265 ° C. and 650 Pa in 30 minutes. After carrying out the reaction for 30 minutes under the same conditions, the temperature is further gradually raised and the pressure is reduced, and the polycondensation reaction is carried out under a reduced pressure of 265 ° C. and 40 Pa or less. During this time, when the desired viscosity is reached while detecting the melt viscosity in the system, nitrogen is introduced to complete the polycondensation reaction.
(2) A sample obtained by dissolving 0.25 g of a polyester composition resin in 5 ml of deuterated chloroform is measured at 60 ° C. using a 400 MHz high-resolution nuclear magnetic resonance apparatus, and the composition is confirmed by analyzing the obtained spectrum. In some cases, an alkaline decomposition-gas chromatography (GC) method is used in combination.
(3) Polyester number average molecular weight Gel permeation chromatography (GPC) is used, measured at a column temperature of 35 ° C., an eluent tetrahydrofuran, and a flow rate of 1 ml / min.
(4) Place a 1 mm square resin piece between cover glasses on the heating plate of a melting point measuring instrument equipped with a fusing temperature thermometer (or temperature indicator), heating plate, magnifier, and polarizing plate. The temperature is raised at ° C./minute, the cover glass is lightly pressed with tweezers, the resin flow is visually confirmed, and the temperature is read.
In the case of a crystalline resin in which spherulites can be confirmed by observation under polarized light, it is also confirmed by the disappearance of the bright part.
(5) Preparation of adhesive In an ethyl acetate solution of a synthesized polyester resin, trifunctional isocyanate (Duranate TPA-100 manufactured by Asahi Kasei Chemical Co., Ltd.), bisphenol A type epoxy resin (Epicoat 827 manufactured by Japan Epoxy Resin Co., Ltd.), carbodiimide compound (Nisshinbo) Carbodilite V-05 made by the company is added and dissolved under stirring at room temperature, and the composition of the adhesive is shown in terms of solid content by weight.
(6) Production of Laminate A 25 μm polyvinylidene fluoride film was subjected to corona treatment, and an ethyl acetate solution of an adhesive was applied and dried to form an adhesive layer having a thickness of 10 μm. On top of that, another polyvinylidene fluoride film having a thickness of 25 μm treated with corona was laminated at 80 ° C., 10 ° C.
Laminate at kg / cm2. The laminated film is cured at 80 ° C. for 50 hours.
(7) Use a sample having an interlayer adhesion strength of 10 mm width, peel 180 degrees at a tensile rate of 10 cm / min at room temperature (20 ° C., 65% RH), and display it as N / cm.

The results are shown below.
Polyester composition: TPA / IPA // 2-MPD / 1,6-HD
= 41/59 // 11/89 (molar ratio)
Number average molecular weight of polyester: 16000
Fusion property (50 ° C. to 200 ° C.): Possible adhesive composition: Polyester / Duranate TPA100 / Epicoat 827 / Carbodilite V-05 = 100/10/10/1 (weight ratio of solid content)
Initial interlayer adhesion: 6.8 N / cm
Interlayer adhesion after 1000 hours treatment at 85 ° C./85% RH: 6.5 N / cm
Interlayer adhesion after 3000 hours treatment at 85 ° C./85% RH: 5.6 N / cm

The results are shown below.
Polyester composition: IPA / OPA / SA // NPG / 1,5-PD / 1,6
-HD = 47/26/27 // 70/12/18 (molar ratio)
Number average molecular weight of polyester: 18000
Fusing property (50 ° C. to 200 ° C.): Possible adhesive composition: Polyester / Duranate TPA100 / Epicoat 827
= 100/10/6 (solid content weight ratio)
Initial interlayer adhesion: 7.1 N / cm
Interlayer adhesion after 1000 hours treatment at 85 ° C./85% RH: 7.0 N / cm
Interlayer adhesion after 3000 hours treatment at 85 ° C./85% RH: 6.4 N / cm

The results are shown below.
Polyester composition: IPA / OPA / SA // NPG / 1,4-CHD
= 40/20/40 // 80/20 (molar ratio)
Number average molecular weight of polyester: 16000
Fusing property (50 ° C. to 200 ° C.): Possible adhesive composition: Polyester / Duranate TPA100 / Epicoat 827
= 100/10/6 (solid content weight ratio)
Initial interlayer adhesion: 5.7 N / cm
Interlayer adhesion after 1000 hours treatment at 85 ° C./85% RH: 5.4 N / cm
Interlayer adhesion after 3000 hours treatment at 85 ° C./85% RH: 4.1 N / cm

The results are shown below.
Polyester composition: IPA / OPA // 2-MPD / 1,6-HD
= 71/29 // 10/90 (molar ratio)
Number average molecular weight of polyester: 17000
Fusing property (50 ° C. to 200 ° C.): Possible adhesive composition: Polyester / Duranate TPA100 / Epicoat 827
= 100/10/6 (solid content weight ratio)
Initial interlayer adhesion: 7.0 N / cm
Interlayer adhesion after 1000 hours treatment at 85 ° C./85% RH: 7.1 N / cm
Interlayer adhesion after 3000 hours treatment at 85 ° C./85% RH: 4.9 N / cm

The following comparative examples are shown for comparison.
Results of Comparative Example 1 Polyester composition: TPA / IPA / AA // EG / NPG
= 30/30/40 // 60/40 (molar ratio)
Number average molecular weight of polyester: 19000
Fusing property (50 ° C. to 200 ° C.): Possible adhesive composition: Polyester / Duranate TPA100 / Epicoat 827
= 100/10/10 (weight ratio of solid content)
Initial interlayer adhesion: 8.4 N / cm
Interlayer adhesion after 1000 hours treatment at 85 ° C./85% RH: 3.9 N / cm
Interlayer adhesion after 3000 hours treatment at 85 ° C./85% RH: 1.5 N / cm

The result of the comparative example 2 is shown.
Polyester composition: TPA / IPA // 2-MPD / 1,6-HD
= 39/61 // 10/90 (molar ratio)
Number average molecular weight of polyester: 16000
Fusing property (50 ° C. to 200 ° C.): Possible adhesive composition: Polyester / Duranate TPA100 / Carbodilite V-05
= 100/10/2 (solid content weight ratio)
Initial interlayer adhesion: 6.3 N / cm
Interlayer adhesion after 1000 hours treatment at 85 ° C./85% RH: 3.4 N / cm
Interlayer adhesion after 3000 hours treatment at 85 ° C./85% RH: 0 N / cm

The sheet-like laminate including the polyester-based adhesive of the present invention and an adhesive layer obtained by using the same has excellent hydrolysis resistance that can withstand 3000 hours or more at 85 ° C./85% RH, and has hydrolysis resistance. Used for required solar cell back surface protection sheets, printed circuit board members such as circuit boards and coverlays, electrical insulation members such as capacitors and flat cables, engine protection members, building materials such as window-laminated films, outdoor laminated steel sheets, etc. I can do it.

Claims (6)

50 to 100 mol% of all ester bonds in the main chain forming the polyester are aromatic carboxylic acid-derived ester bonds, and carbon contained in a group existing between the ester bond and the ester bond in the main chain. A polyester having a number of 3 or more, a number average molecular weight of 5000 to 35000, a polyester having a fusing temperature between 50 and 200 ° C., A, a bifunctional or higher isocyanate compound and / or When the blocked isocyanate compound is B and the bifunctional or higher functional epoxy compound is C, A / B (weight ratio)
100/0 to 70/30, and a polyester-based adhesive comprising a resin composition containing A / C (weight ratio) at a ratio of 99.9 / 0.1 to 70/30, and A sheet-like laminate of a film or / and a metal foil or / and a metal plate or / and a metal thin film or / and a ceramic thin film comprising an adhesive layer obtained therefrom. The sheet-like laminate according to claim 1, wherein the polyester-based adhesive of claim 1 contains an epoxy compound reaction accelerator. The film which comprises the laminated body of Claim 1 and Claim 2 is a polyester-type film,
Polycarbonate film, fluororesin film, acrylic resin film,
Polyolefin film, copolymer resin film of olefin and oxygen-containing monomer,
The metal foil that also constitutes the laminate is a copper foil, an aluminum foil or a thin film thereof, a steel foil or a plate, and the ceramic thin film that also constitutes the laminate is silicon oxide or / and aluminum oxide. The sheet-like laminated body of 1 and Claim 2. The sheet-like laminate according to any one of claims 1, 2, and 3, wherein the laminate according to claim 1, claim 2, and claim 3 is used for a back surface protection sheet of a solar cell module. The sheet-like laminate according to any one of claims 1, 2, and 3, wherein the laminate of claim 1, claim 2, and claim 3 is used as a circuit material, a flat cable material, or a bus bar material. The sheet-like laminate according to any one of claims 1, 2, and 3, wherein the laminate according to claim 1, claim 2, and claim 3 is used for a laminated steel sheet.