WO2019198473A1

WO2019198473A1 - Weather resistant adhesive composition

Info

Publication number: WO2019198473A1
Application number: PCT/JP2019/012396
Authority: WO
Inventors: 裕樹岡島; 示野　勝也
Original assignee: 東洋紡株式会社
Priority date: 2018-04-12
Filing date: 2019-03-25
Publication date: 2019-10-17
Also published as: CN111511796A; JP7306380B2; TW201943760A; JPWO2019198473A1

Abstract

Provided are a polyester polyol and a weather resistant adhesive which exhibit practical levels of adhesiveness, resistance to moist heat, and resistance to weather due to low temperature and short term aging. The polyester polyol (A) comprises a polycarboxylic acid component and a polyhydric alcohol component as copolymerization components, comprises a hydroxy pivalic acid neopentylglycol component as the polyhydric alcohol component, includes 10 mol% or less of a terephthalic acid component when the total polycarboxylic acid component is 100 mol%, and has an acid value of 20 to 150 equivalent/10⁶ g.

Description

Weather-resistant adhesive composition

The present invention relates to a polyester polyol and a weather resistant adhesive composition suitable for outdoor industrial use and the like.

A polyurethane-based adhesive containing a polyester polyol is known as an adhesive composition having weather resistance for outdoor industrial applications, such as building materials and solar cell panel materials.

Patent Document 1 discloses a specific polyurethane-based adhesive, which is excellent in long-term wet heat resistance. Patent Document 2 discloses a laminate in which at least two layers of substrates are bonded together with a polyurethane adhesive, and is said to be excellent in weather resistance.

JP 2010-43238 A JP 2007-320218 A

In the curing reaction of polyurethane, for example, in the case of coating to metal plates or adhesion between metal plates, it is possible to apply a high temperature close to 200 ° C. and shorten the curing time. However, there are many cases where high temperature cannot be applied depending on the type and form of the substrates to be bonded. The production of a laminate including a resin film as described in Patent Document 1 and Patent Document 2 is typical of such a case. In the example of Patent Document 1, aging is performed at 60 ° C. for 7 days, In the Example of patent document 2, the laminated body is manufactured by performing aging for 5 days at 50 degreeC. As described above, in the prior art, it is generally performed to perform an aging treatment for a long time of about 5 to 7 days at a relatively low temperature of about 50 to 60 ° C. It is preferable from the viewpoints of energy saving, improvement in workability / productivity and cost reduction if the aging temperature is set to the same level as or lower than the current level and the aging time can be shortened.

Therefore, an object of the present invention is to provide a weather-resistant adhesive that exhibits a practical level of adhesion, heat-and-moisture resistance, and weather resistance by low-temperature and short-term aging.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that an adhesive composition containing a polyester polyol and a polyisocyanate compound containing neopentyl glycol hydroxypivalate and having a certain range of acid values, It has been found that good adhesiveness, moist heat resistance and weather resistance are exhibited by short-term aging for about 1 day at a relatively low temperature of about 40 to 60 ° C., and the present invention has been completed. That is, this invention consists of the following structures.

When the polycarboxylic acid component and the polyhydric alcohol component are used as a copolymerization component, the polyhydric alcohol component includes a hydroxypivalate neopentyl glycol component, and the total polyvalent carboxylic acid component is 100 mol%, the terephthalic acid component is 10 Polyester polyol (A) having a mol% or less and an acid value of 20 to 150 equivalents / 10 ⁶ g.

When the total polyol component of the polyester polyol (A) is 100 mol%, it preferably contains 10 mol% or more of neopentyl glycol hydroxypivalate, and moreover 3-methyl-1,5- It is preferable that it contains a pentanediol component. The polyester polyol (A) preferably has a glass transition temperature of −20 to 20 ° C. and a number average molecular weight of 4,000 to 50,000.

A weather-resistant adhesive composition containing the polyester polyol (A) and a polyisocyanate compound (B) containing an aliphatic polyisocyanate compound and / or an alicyclic polyisocyanate compound.

The polyisocyanate compound (B) includes hexamethylene diisocyanate adduct, hexamethylene diisocyanate isocyanurate, hexamethylene diisocyanate biuret, isophorone diisocyanate adduct, isophorone diisocyanate isocyanurate, and isophorone diisocyanate biuret. It is preferable that it is 1 type, or 2 or more types selected from the group which consists of.

The compounding ratio of the polyester polyol (A) and the polyisocyanate compound (B) is preferably 1 to 20 parts by mass of the polyisocyanate compound (B) with respect to 100 parts by mass of the polyester polyol (A).

A laminate obtained by laminating an adhesive layer made of the weather-resistant adhesive composition according to any one of the above and a base material. The base material is preferably one or more of a film selected from the group consisting of a polyester film, a fluoropolymer film, a polyethylene film, and a vinyl acetate copolymer film.

The adhesive composition using the polyester polyol of the present invention exhibits good adhesiveness, moist heat resistance and weather resistance by short-term aging for about 1 day at a relatively low temperature of about 40 to 60 ° C. For this reason, it is possible to save energy, improve workability / productivity, and reduce costs.

When polyhydric carboxylic acid component and polyhydric alcohol component are used as copolymerization components, hydroxypivalate neopentyl glycol is included as the polyhydric alcohol component, and the total polycarboxylic acid component is 100 mol%, terephthalic acid component is 10 mol. % Polyester polyol (A) having an acid value of 20 to 150 equivalents / 10 ⁶ g. A weather-resistant adhesive composition containing the polyester polyol (A) and a polyisocyanate compound (B) containing an aliphatic polyisocyanate compound and / or an alicyclic polyisocyanate compound.

<Polyester polyol (A)>
The polyester polyol (A) of the present invention preferably has a chemical structure obtained by polycondensation of a polyvalent carboxylic acid and a polyhydric alcohol. Examples of the polyvalent carboxylic acids include aliphatic dibasic acids (aliphatic dicarboxylic acids) such as succinic acid, glutaric acid, adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, brassic acid, dimer acid and hydrogenated products thereof. ), One or more dibasic acids such as aromatic dibasic acids (aromatic dicarboxylic acids) such as terephthalic acid, isophthalic acid, orthophthalic acid and naphthalenedicarboxylic acid can be used.

From the viewpoint of improving weather resistance, it is effective to keep the copolymerization ratio of the terephthalic acid component low. When the total polyvalent carboxylic acid component is 100 mol%, the terephthalic acid component is 10 mol% or less. is necessary. Preferably it is less than 10 mol%, More preferably, it is 5 mol% or less, More preferably, it is 1 mol% or less, and it may be 0 mol%.
By making it within the above range, good weather resistance can be expressed.

From the viewpoint of improving heat and humidity resistance, the aromatic dicarboxylic acid component is preferably an isophthalic acid component, an orthophthalic acid component or a 2,6-naphthalenedicarboxylic acid component, and more preferably an isophthalic acid component or an orthophthalic acid component. When the total polyvalent carboxylic acid component is 100 mol%, the total amount of isophthalic acid component and orthophthalic acid component is preferably 70 mol% or more, more preferably 80 mol% or more, and still more preferably 90 mol%. Or more, particularly preferably 95 mol% or more. Moreover, it is preferable that it is 99 mol% or less, More preferably, it is 98 mol% or less. By setting it within the above range, good adhesiveness can be expressed.

As the aromatic dicarboxylic acid component, it is preferable to use an isophthalic acid component and an orthophthalic acid component in combination, and the blending ratio (molar ratio) is preferably isophthalic acid component / orthophthalic acid component = 90 to 50/10 to 50, More preferably, it is 80-60 / 20-40, and more preferably 75-65 / 25-35. By being within the above range, excellent adhesiveness, moist heat resistance and weather resistance can be exhibited.

It is necessary to contain a neopentyl glycol hydroxypivalate component as a polyhydric alcohol component. By including a hydroxypivalate neopentyl glycol component, excellent adhesiveness can be expressed. When the total polyhydric alcohol component is 100 mol%, the hydroxypivalate neopentyl glycol component is preferably 1 mol% or more, more preferably 5 mol% or more, still more preferably 10 mol% or more, Most preferably, it is 20 mol% or more. Moreover, it is preferable that it is 60 mol% or less, More preferably, it is 50 mol% or less, More preferably, it is 45 mol% or less. By setting it within the above range, good adhesiveness with the substrate can be expressed.

Examples of the polyhydric alcohol component other than neopentyl glycol hydroxypivalate include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1 Aliphatic glycols such as 1,12-dodecanediol, 2-methyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, alicyclic glycols such as cyclohexanediol and hydrogenated xylylene glycol , Aromatic ring-containing glycosyl such as xylylene glycol It can be used one or more glycols, such as Le.

Preferably, it is an aliphatic glycol component containing a long chain aliphatic structure, preferably an aliphatic glycol component having 5 or more carbon atoms, more preferably an aliphatic glycol component having 6 to 12 carbon atoms, from the viewpoint of heat and heat resistance. . Among them, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol 1,12-dodecanediol or 3-methyl-1,5-pentanediol is more preferable, and 3-methyl-1,5-pentanediol is particularly preferable. The aliphatic glycol component containing a long-chain aliphatic structure is preferably contained in an amount of 50 mol% or more, more preferably 60 mol% or more when the total polyhydric alcohol component is 100 mol%. Moreover, it is preferable that it is 99 mol% or less, More preferably, it is 95 mol% or less, More preferably, it is 90 mol% or less, Most preferably, it is 80 mol% or less. By setting it to the lower limit value or more, good wet heat resistance can be expressed, and by setting the upper limit value or less, good adhesiveness can be expressed.

When the total polyhydric alcohol component is 100 mol%, the total content of the neopentyl glycol hydroxypivalate component and the 3-methyl-1,5-pentanediol component is preferably 20 mol% or more. Preferably it is 30 mol% or more, More preferably, it is 40 mol% or more. By being within the above range, excellent adhesiveness, moist heat resistance and weather resistance can be exhibited. Further, the total of the neopentyl glycol component of hydroxypivalate, the 3-methyl-1,5-pentanediol component and the aliphatic glycol component containing other long chain aliphatic structure is preferably 80 mol% or more, more Preferably it is 90 mol% or more, More preferably, it is 95 mol% or more, and it may be 100 mol%.

It is a polyisocyanate compound to introduce a branch by copolymerizing a small amount of a trifunctional or higher polyhydric carboxylic acid component such as trimellitic anhydride or pyromellitic anhydride or a trifunctional or higher polyhydric alcohol component such as trimethylolpropane. The effect of improving the reactivity with (B) may be exhibited, which is a preferred embodiment. The trifunctional or higher polyvalent carboxylic acid component is preferably 5 mol% or less, more preferably 3 mol% or less, and even more preferably 1 mol% or less when the total polycarboxylic acid component is 100 mol%. It is. The trifunctional or higher polyhydric alcohol component is preferably 5 mol% or less, more preferably 3 mol% or less, and even more preferably 1 mol% or less, when the total polyhydric alcohol component is 100 mol%. It is. If the amount is too large, too many branches may be formed, and the polyester polyol (A) may be gelled.

In producing the polyester polyol (A) of the present invention, a conventionally known polymerization catalyst can be used. For example, titanium compounds such as tetra-n-butyl titanate, tetraisopropyl titanate, titanium oxyacetylacetonate, antimony compounds such as tributoxyantimony and antimony trioxide, germanium compounds such as tetra-n-butoxygermanium, germanium oxide, etc. Can be used. These catalysts may be used alone or in combination of two or more. Titanium compounds are preferred from the viewpoint of polymerization reactivity.

The acid value of the polyester polyol (A) used in the present invention is 20 to 150 equivalent / 10 ⁶ g, preferably 50 to 120 equivalent / 10 ⁶ g, and more preferably 70 to 100 equivalent / 10 ⁶ g. It is. By setting the acid value to the lower limit value or more, an aging time shortening effect can be expressed, and by setting the acid value to the upper limit value or less, excellent wet heat resistance of the adhesive layer obtained from the weather resistant adhesive composition is expressed. be able to.

The method for adjusting the acid value of the polyester polyol (A) is not particularly limited, and the acid value can be adjusted by intentionally polymerizing many carboxyl group terminals or by introducing carboxyl groups into the polyester polyol. The method of introducing a carboxyl group into a polyester polyol is a method of post-adding an acid anhydride under normal pressure and nitrogen atmosphere after polymerizing the polyester polyol to give an acid value, or an oligomer state before making the polyester high molecular weight There is a method in which these acid anhydrides are introduced into a product and then polymerized by polycondensation under reduced pressure. When the former method and trimellitic anhydride are used, the target acid value is particularly easily obtained. Acid anhydrides that can be used in these reactions include trimellitic anhydride as described above, phthalic anhydride, pyromellitic anhydride, succinic anhydride, 1,8-naphthalic anhydride, 1,2 anhydrous -Cyclohexanedicarboxylic acid, cyclohexane-1,2,3,4-tetracarboxylic acid = 3,4-anhydride, ethylene glycol bisanhydro trimellitate, 5- (2,5-dioxotetrahydro-3-furanyl) Aromatic carboxylic anhydrides and alicyclic carboxylic anhydrides such as -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, naphthalene-1,8: 4,5-tetracarboxylic dianhydride It is preferable that one or more of these can be selected and used.

If an acid anhydride or the like is post-added (post-added) after polyester polymerization to impart an acid value, the total amount of polyvalent carboxylic acid components may exceed 100 mol%. In this case, the total amount of the polyvalent carboxylic acid component excluding the component after addition (post addition) of acid anhydride or the like is calculated as 100 mol%.

The range of the glass transition temperature of the polyester polyol (A) of the present invention is preferably −20 to 20 ° C., more preferably 0 to 10 ° C. In order to obtain such a polyester polyol, a dibasic acid or glycol having a long aliphatic chain may be introduced into the copolymer component. In order to have heat and heat resistance, it is preferable to copolymerize an aliphatic glycol having 5 or more carbon atoms. From the viewpoint of adhesiveness, 3-methyl-1,5-pentane is combined with neopentyl glycol hydroxypivalate. It is particularly preferred to use a diol. By making the glass transition temperature not more than the above upper limit value, it is possible to exert a good adhesive force to the substrate, and by making the glass transition temperature not less than the above lower limit value, the adhesive layer made of the weather resistant adhesive composition is not too flexible. Excellent adhesion and moisture and heat resistance can be expressed.

The number average molecular weight of the polyester polyol (A) of the present invention is not particularly limited, but is preferably 4,000 to 50,000, and more preferably 8,000 to 20,000. By making the number average molecular weight of the polyester polyol (A) equal to or more than the lower limit value, the molecular weight of the crosslinked ring is not reduced too much, and the adhesive layer made of the weather-resistant adhesive composition has an appropriate hardness and good adhesive strength. It can be demonstrated. Moreover, it can fully react with polyisocyanate (B) by making the number average molecular weight of polyester polyol (A) below the said upper limit, and can exhibit favorable heat-and-moisture resistance.

<Polyisocyanate compound (B)>
The polyisocyanate compound (B) used in the present invention preferably contains an aliphatic polyisocyanate compound and / or an alicyclic polyisocyanate compound. As the aliphatic polyisocyanate compound, an aliphatic diisocyanate compound is preferable, and specific examples include hexamethylene diisocyanate. The alicyclic polyisocyanate compound is preferably an alicyclic diisocyanate compound, and specifically, isophorone diisocyanate can be given as a suitable example. Hexamethylene diisocyanate or isophorone diisocyanate is preferable in terms of improving weather resistance.

The polyisocyanate compound (B) may be an isocyanurate body, a biuret body or an adduct body, and an isocyanurate body is particularly preferable. Specific examples include hexamethylene diisocyanate adduct, hexamethylene diisocyanate isocyanurate, hexamethylene diisocyanate biuret, isophorone diisocyanate adduct, isophorone diisocyanate isocyanurate, and isophorone diisocyanate biuret. These can be used alone or in combination of two or more.

The content of the polyisocyanate compound (B) is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and further preferably 5 parts by mass or more with respect to 100 parts by mass of the polyester polyol (A). It is. Moreover, it is preferable that it is 20 mass parts or less, More preferably, it is 18 mass parts or less, More preferably, it is 15 mass parts or less. By setting it within the above range, good adhesiveness can be expressed.

<Weather-resistant adhesive composition>
The weather resistant adhesive composition of the present invention is preferably a composition containing the polyester polyol (A) and the polyisocyanate compound (B). In the weather-resistant adhesive composition of the present invention, an end-capping agent such as a carbodiimide compound, an oxazoline compound, or an epoxy compound is optionally used to block a carboxyl group generated when hydrolysis occurs in the polyester polyol (A). You may mix | blend in the ratio. It is preferable that the compounding quantity of the said end blocker is 1 mass part or more with respect to 100 mass parts of polyester polyol (A), More preferably, it is 2 mass parts or more. By setting the blending amount, the end-capping effect of the carboxyl group can be obtained. Moreover, it is preferable that it is 10 mass parts or less, More preferably, it is 5 mass parts or less. By setting the blending amount, good adhesiveness can be expressed.

Examples of the carbodiimide compound include N, N′-di-o-toluylcarbodiimide, N, N′-diphenylcarbodiimide, N, N′-di-2,6-dimethylphenylcarbodiimide, N, N′-bis (2, 6-diisopropylphenyl) carbodiimide, N, N′-dioctyldecylcarbodiimide, N-triyl-N′- cyclohexylcarbodiimide, N, N′-di-2,2-di-tert- butylphenylcarbodiimide, N-triyl-N '-Phenylcarbodiimide, N, N'-di-p-nitrophenylcarbodiimide, N, N'-di-p-aminophenylcarbodiimide, N, N'- -di- p -hydroxyphenylcarbodiimide, N, N'-di -Cyclohexylcarbodiimide, N, N'-di-p-toluylcarbo Imide and the like.

Examples of the oxazoline compound include monooxazoline compounds such as 2-oxazoline, 2-methyl-2-oxazoline, 2-phenyl-2-oxazoline, 2,5-dimethyl-2-oxazoline, and 2,4-diphenyl-2-oxazoline. 2,2 ′-(1,3-phenylene) -bis (2-oxazoline), 2,2 ′-(1,2-ethylene) -bis (2-oxazoline), 2,2 ′-(1,4 And dioxazoline compounds such as -butylene)-bis (2-oxazoline) and 2,2 '-(1,4-phenylene) -bis (2-oxazoline).

Examples of the epoxy compound include diglycidyl ethers of aliphatic diols such as 1,6-hexanediol, neopentyl glycol, and polyalkylene glycol, sorbitol, sorbitan, polyglycerol, pentaerythritol, diglycerol, glycerol, and trimethylolpropane. Polyglycidyl ethers of aliphatic polyols such as, polyglycidyl ethers of alicyclic polyols such as cyclohexanedimethanol, aliphatic or aromatic such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, trimellitic acid, adipic acid, sebacic acid Diglycidyl ester or polyglycidyl ester of polycarboxylic acid, resorcinol, bis- (p-hydroxyphenyl) methane, 2,2-bis- (p-hydroxypheny) ) Diglycidyl ether or polyglycidyl ether of polyphenols such as propane, tris- (p-hydroxyphenyl) methane, 1,1,2,2-tetrakis (p-hydroxyphenyl) ethane, N, N-diglycidylaniline N, N-diglycidyl toluidine, N, N, N ′, N′-tetraglycidyl-bis- (p-aminophenyl) methane, N-glycidyl derivatives of amines, triglycidyl derivatives of aminofails, triglycidyl Examples thereof include tris (2-hydroxyethyl) isocyanurate, triglycidyl isocyanurate, orthocresol type epoxy, phenol novolac type epoxy, and bisphenol type polyfunctional epoxy compound.

The weather-resistant adhesive composition of the present invention may contain known additives such as ultraviolet absorbers and antioxidants, and may further improve weather resistance and wet heat resistance.

Using the weather-resistant adhesive composition of the present invention as an adhesive layer, a laminate in which the adhesive layer and a substrate are laminated can be obtained. As a base material, the 1 type (s) or 2 or more types of the film selected from the group which consists of a polyester film, a fluorine-type polymer film, a polyethylene film, and a vinyl acetate copolymer film can be mentioned. The laminate may be a film / adhesive layer / film three-layer laminate, a film / adhesive layer / film / adhesive layer / film five-layer laminate, or a laminate having more layers. good. Further, each film constituting the laminate may be made of the same kind of material or different kinds of material.

The laminate may be one obtained by applying a weather resistant adhesive composition on a substrate and drying it, or separately preparing an adhesive layer made of a weather resistant adhesive composition, and using the adhesive layer as a substrate. It may be pasted. The conditions for applying the weather resistant adhesive composition on the substrate and drying are not particularly limited, but it is preferably 40 to 250 ° C. If it is less than 40 degreeC, drying time will take time and it is not rational as industrial production. Moreover, there is a possibility that the coating film is not completely dried. On the other hand, if it exceeds 250 ° C., a high-performance drying furnace is required, which is not desirable. Although the drying method is not limited, a known method such as a hot air dryer, induction heating, near infrared heating, far infrared heating, indirect heating can be applied. The thickness of the adhesive layer after drying is generally 5 to 30 μm, preferably 10 to 20 μm.

Examples of the polyester constituting the polyester film include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), and polycyclohexanedimethanol-terephthalate (PCT).

The fluorinated polymer constituting the fluorinated polymer film is, for example, a fluorinated polyolefin and a polyolefin-fluorinated polyolefin copolymer, and specifically, polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), polychloro Trifluoroethylene (PCTFE), polyethylene tetrafluoroethylene (ETFE), polytetrafluoroethylene (PTFE), tetrafluoroethylene perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP) Etc.

Examples of the polymer constituting the polyethylene film include low density polyethylene, high density polyethylene, ultrahigh molecular weight polyethylene, and those obtained by adding various additives to these.

Examples of the polymer constituting the vinyl acetate copolymer film include ethylene-vinyl acetate copolymers and those obtained by adding various additives to these.

The substrate used in the present invention may or may not be surface treated. It is desirable to perform surface treatment such as corona treatment, flame treatment, and plasma treatment for the purpose of improving adhesion on the coated surface and the adhesive surface.

This application claims the benefit of priority based on Japanese Patent Application No. 2018-076800 filed on April 12, 2018. The entire contents of the above Japanese Patent Application No. 2018-076800 are incorporated herein by reference.

Hereinafter, the present invention will be described using examples. In the examples, the term “parts” means parts by mass. Each measurement item followed the following method.

(Polyester polyol (A) composition)
The composition and composition ratio of the polyester polyol (A) were determined by ¹ H-NMR measurement (proton nuclear magnetic resonance spectroscopy) with a resonance frequency of 400 MHz. The measuring apparatus was an NMR apparatus 400-MR manufactured by VARIAN, and deuterated chloroform was used as a solvent. In addition, when the acid value of the polyester polyol (A) was increased by post-acid addition, the molar ratio of each component was calculated with the total of the acid components other than the acid component used for the post-acid addition being 100 mol%.

(Number average molecular weight Mn)
4 mg of a sample (polyester polyol (A)) was dissolved in 4 ml of tetrahydrofuran (added with 5 mM tetrabutylammonium chloride) and then filtered through a membrane filter having a pore size of 0.2 μm to obtain a sample solution for measurement. The number average molecular weight of the polyester polyol (A) was measured by gel permeation chromatography at a column temperature of 40 ° C. and a flow rate of 1 ml / min using tetrahydrofuran, the mobile phase was TOSOH HLC-8220, and the apparatus was a differential refractive index detector. . As the column, Showa Denko Co., Ltd. shodex KF-802, KF-804, KF-806 connected in series was used. The number average molecular weight was a standard polystyrene equivalent value, and was calculated by omitting a low molecular weight (oligomer) portion corresponding to a molecular weight of less than 1,000.

(Glass transition temperature (Tg))
The measurement was made with a differential scanning calorimeter (SII, DSC-200). A sample (polyester polyol (A)) 5 mg was put in an aluminum holding lid container and sealed. First, it was cooled to −50 ° C. using liquid nitrogen and then heated to 150 ° C. at 20 ° C./min. In the endothermic curve obtained in the process, the base line extension before the endothermic peak (below the glass transition temperature) and the tangent to the endothermic peak (maximum slope between the peak rising part and peak apex) The glass transition temperature (Tg, unit: ° C.) was defined as the temperature at the intersection with the tangent line.

(Acid value (AV))
0.2 g of a sample (polyester polyol (A)) was precisely weighed and dissolved in 40 ml of chloroform. Next, titration was performed with an ethanol solution of 0.01 N potassium hydroxide. Phenolphthalein was used as an indicator. The measured value was converted to the equivalent per 10 ⁶ g of the sample, and the unit was equivalent / 10 ⁶ g.

Production Example of Polyester Polyol (P1) In a reaction vessel equipped with a stirrer, a condenser and a thermometer, 415 parts of isophthalic acid, 180 parts of orthophthalic acid, 7 parts of trimellitic anhydride, 333 parts of neopentyl glycol hydroxypivalate, 3-methyl- 449 parts of 1,5-pentanediol and 0.03 mol% of TBT as a catalyst with respect to the total acid components were charged, and a transesterification reaction was performed from 160 ° C. to 230 ° C. over 4 hours. Next, the pressure inside the system was gradually reduced, the pressure was reduced to 5 mmHg over 20 minutes, and a polycondensation reaction was performed at 250 ° C. for 60 minutes under a vacuum of 0.3 mmHg or less. The mixture was cooled to 215 ° C. under a nitrogen stream, 7 parts of trimellitic anhydride was added, and the reaction was performed for 30 minutes. As a result of composition analysis by NMR, the obtained polyester polyol (P1) has an acid component in a molar ratio of isophthalic acid / orthophthalic acid / trimellitic acid = 69/30/1, and a glycol component in a molar ratio of hydroxypivalic acid neo Pentyl glycol / 3-methyl-1,5-pentanediol = 30/70. The number average molecular weight was 14,000, the glass transition temperature was 8 ° C., and the acid value was 80 equivalents / 10 ⁶ g.

Production Examples of Polyester Polyols (P2) to (P12) Polyester polyols (P2) to (P12) were produced according to the production examples of the polyester polyol (P1) except that the types and blending ratios of the raw materials were changed. The results are shown in Table 1.

Hereinafter, the curing agent (polyisocyanate compound (B)) and additives are as follows.
Curing agent 1: Polyisocyanate compound, hexamethylene diisocyanate (HDI) isocyanurate body “Desmodur (registered trademark) N3300 manufactured by Sumika Bayer”.
Curing agent 2: Polyisocyanate compound, isophorone diisocyanate (IPDI) isocyanurate body “Desmodur Z4470 manufactured by Sumika Bayer”.
Curing agent 3: Polyisocyanate compound, toluene diisocyanate (TDI) isocyanurate body “Desmodur IL 1351 manufactured by Sumika Bayer”.
Additive (epoxy compound): Bisphenol type polyfunctional epoxy compound (jER (registered trademark) 828 manufactured by Mitsubishi Chemical).

Example 1
(Production of weather-resistant adhesive composition (1))
100 parts of the resin P1, 4 parts of the epoxy resin, and 382 parts of ethyl acetate were mixed, and 10 parts of the curing agent was blended and mixed to obtain a weather resistant adhesive composition (1).

(Evaluation of initial adhesive strength and heat and humidity resistance)
After applying the weather-resistant adhesive composition (1) to the substrate A with an applicator so that the dry film thickness (film thickness after drying) is 8 μm and volatilizing the solvent, the substrate B is used with a dry laminator And then crimped (dry lamination). Dry lamination was performed at a roll temperature of 90 ° C., a roll load of 3 kg / cm, and a speed of an object to be bonded of 1 m / min. Subsequently, the weather-resistant adhesive composition was cured by aging at 50 ° C. for 1 day to obtain a base material A / adhesive layer / base material B laminate. In the same manner, a substrate A / adhesive layer / substrate C laminate was obtained. In Example 1, the base material A is a polyester film (Toyobo, Shine Beam (registered trademark) Q1215, thickness 250 μm), the base material B is a PVF film (DuPont, thickness 25 μm), and the base material C is an EVA film. (SANVIC, thickness 300 μm) was used.

Each laminated body after the aging is cut into a strip shape having a width of 15 mm, and the base A and the base B and the base A and the base C are obtained using Tensilon (registered trademark) (UTM-IV, manufactured by Toyo Sokki Co., Ltd.). The peel strength (T-peel peel, pulling speed 100 mm / min) was measured and used as the initial adhesive strength. The evaluation results are shown in Table 2.
Evaluation criteria: Base material A / Base material B
○: 9 N / 15 mm or more Δ: 6 N / 15 mm or more and less than 9 N / 15 mm X: 6 N / 15 mm or less Evaluation criteria: Base material A / Base material C
○: 8N / 15mm or more △: 6N / 15mm or more and less than 8N / 15mm ×: Less than 6N / 15mm

The laminated body of the base material A / adhesive layer / base material B after the aging was subjected to an environmental load at 121 ° C., 100% RH, 90 hours using a retort tester (ES-315 manufactured by Tommy Industries Co., Ltd.). Then, it was cut into a strip shape with a width of 15 mm, and the peel strength (T-peel peel, pulling speed 100 mm / min) between the base A and the base B was measured.
Evaluation criteria: ○: 9 N / 15 mm or more Δ: 6 N / 15 mm or more, less than 9 N / 15 mm ×: less than 6 N / 15 mm

(Evaluation of degree of cure)
A weather resistant adhesive composition (1) was applied to a polyester film (Toyobo E5101, thickness 50 μm, corona-treated surface) with an applicator so that the dry film thickness was 10 μm, and the solvent was volatilized. P2161 (thickness 50 μm, non-corona-treated surface) was pressure-bonded (dry lamination) using a dry laminator. Dry lamination was performed at a roll temperature of 120 ° C., a roll load of 3 kg / cm, and a pressure-bonded article speed of 1 m / min. Next, aging was performed at 50 ° C. for 48 hours to cure the weather resistant adhesive composition, and the polypropylene film was peeled off to obtain a polyester film / adhesive layer laminate.

The polyester film / adhesive layer laminate after aging was cut into strips of 2.5 cm in length and 10 cm in width and weighed (this weight is designated as A), and toluene / methyl ethyl ketone = 1/1 (weight ratio). It was immersed in the mixed solution for 1 hour. After the immersion, the laminate was taken out and dried with a hot air dryer for 1 hour, and the weight was measured (this weight is designated as B). Thereafter, the adhesive layer remaining on the laminate was scraped off, and the weight of only the polyester film was measured (this weight is defined as C). The numerical value calculated by the following formula was defined as the degree of cure (%). The evaluation results are shown in Table 2.
Curing degree (%) = {(AC) / (BC)} × 100
Evaluation criteria: ○: 65% or more △: 40% or more and less than 65% ×: Less than 40%

(Evaluation of weather resistance)
A weather resistant adhesive composition (1) is applied to a polyester film (manufactured by Toyobo, Shine Beam (registered trademark) Q1210, thickness 50 μm) with an applicator so that the dry film thickness is 20 μm, and the solvent is volatilized. The film (Toyobo P2161, thickness 50 μm, non-corona-treated surface) was pressure-bonded using a dry laminator. Dry lamination was performed at a roll temperature of 120 ° C., a roll load of 3 kg / cm, and a pressure-bonded article speed of 1 m / min. Subsequently, the weather-resistant adhesive composition was cured by aging at 40 ° C. for 24 hours, and the polypropylene film was peeled off to obtain a polyester film / adhesive layer laminate.

Ultraviolet rays were irradiated from the adhesive layer side of the polyester film / adhesive layer laminate after aging. Ultraviolet irradiation is performed using a UV irradiation tester (Iwasaki Electric Co., Ltd., iSuper UV Tester (registered trademark), SUV-W151), irradiation conditions are 60 ° C. (black panel temperature), relative humidity 60%, irradiation The irradiation time was 24 hours. The Cob value of the laminate of the polyester film / adhesive layer before and after UV irradiation was measured using a color difference meter (ZE2000 manufactured by Nippon Denshoku Co., Ltd.), and the difference before and after UV irradiation was used as an indicator of weather resistance. The larger the value, the greater the degree of yellowing, indicating poorer weather resistance. The evaluation results are shown in Table 2.
Evaluation criteria: ○: Less than +15 ×: +15 or more

Examples 2 to 10, Comparative Examples 1 to 3, Reference Example 1
According to the weather resistant adhesive composition (1) of Example 1, weather resistant adhesive composition (2) to weather resistant adhesive composition (14) were produced. Next, the weather-resistant adhesive composition and the substrate were changed as shown in Table 2, and the same evaluation as in Example 1 was performed. The evaluation results are shown in Table 2.

In the prior art, aging treatment for a long time of about 5 to 7 days at a relatively low temperature of about 50 to 60 ° C. is generally performed. It is preferable from the viewpoints of energy saving, improvement in workability / productivity and cost reduction if the aging temperature is set to the same level as or lower than the current level and the aging time can be shortened.

Claims

When the polycarboxylic acid component and the polyhydric alcohol component are used as a copolymerization component, the polyhydric alcohol component includes a hydroxypivalate neopentyl glycol component, and the total polyvalent carboxylic acid component is 100 mol%, the terephthalic acid component is 10 Polyester polyol (A) having a mol% or less and an acid value of 20 to 150 equivalents / 10 6 g.
The polyester polyol (A) according to claim 1, which contains 10 mol% or more of a neopentyl glycol hydroxypivalate component when the total polyhydric alcohol component is 100 mol%.
The polyester polyol (A) according to claim 1 or 2, further comprising a 3-methyl-1,5-pentanediol component.
The polyester polyol (A) according to any one of claims 1 to 3, having a glass transition temperature of -20 to 20 ° C and a number average molecular weight of 4,000 to 50,000.
A weather resistant adhesive composition comprising the polyester polyol (A) according to any one of claims 1 to 4 and a polyisocyanate compound (B) containing an aliphatic polyisocyanate compound and / or an alicyclic polyisocyanate compound.
The polyisocyanate compound (B) includes hexamethylene diisocyanate adduct, hexamethylene diisocyanate isocyanurate, hexamethylene diisocyanate biuret, isophorone diisocyanate adduct, isophorone diisocyanate isocyanurate, and isophorone diisocyanate biuret. The weather-resistant adhesive composition according to claim 5, which is one or more selected from the group consisting of:
The weather resistance according to claim 5 or 6, wherein the blending ratio of the polyester polyol (A) and the polyisocyanate compound (B) is 1 to 20 parts by mass of the polyisocyanate compound (B) with respect to 100 parts by mass of the polyester polyol (A). Adhesive composition.
A laminate in which an adhesive layer comprising the weatherable adhesive composition according to any one of claims 5 to 7 and a substrate are laminated.
The laminate according to claim 8, wherein the substrate is one or more of films selected from the group consisting of a polyester film, a fluoropolymer film, a polyethylene film, and a vinyl acetate copolymer film.