JP2003238930A - Resin composition for adhesive and laminate using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition for an adhesive comprising a copolyester that has excellent tackiness and adhesiveness to a substrate such as a polyethylene terephthalate sheet, a polycarbonate sheet, an FPC (flexible printed circuit), a glass, or a substrate such as the above with an ITO vapor- deposited thereon, and has an extremely good hydrolysis resistance, and to provide a laminate using the composition. <P>SOLUTION: This resin composition for an adhesive comprises a polyester having a carbonate bond in a molecule. It is preferable that a polycarbonate diol is copolymerized as a diol component of the polyester. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for adhesives and a laminate using the same, and more specifically to a polyethylene terephthalate sheet (film) used for applications such as transparent touch panels and membranes for computer keyboards. (Including the following), a polycarbonate sheet, a substrate such as glass, or a material obtained by vapor-depositing ITO (indium tin oxide) on these substrates or an FPC (flexible printed wiring board) (hereinafter referred to as tackiness). It may also be referred to)), and relates to a resin composition for a tacky-adhesive agent, which has a copolyester as a main component and which has excellent adhesiveness and extremely excellent hydrolysis resistance, and a laminate using the same.

[0002]

2. Description of the Related Art Adhesives used for applications such as transparent touch panels and membranes for computer keyboards are difficult to achieve both tackiness and adhesiveness. Here, tackiness is an important performance to prevent misalignment during positioning before laminating, while adhesiveness is very important to prevent peeling when used as a final product. Performance. For example, the transparent touch panel is ITO vapor deposition P
It has a structure in which an ET film and ITO vapor-deposited glass are bonded together, and a tacky adhesive is used for this bonding. At the time of this bonding, it is important to align the upper and lower base materials so as not to shift. Therefore, the base materials are lightly pasted together, accurately positioned, and then thermocompression bonded,
A method of firmly adhering is often used. Adequate tackiness (tackiness) is very important for accurate positioning, while a strong adhesive force is essential for the final product to prevent peeling of the substrate.

As a general-purpose resin composition used as a tacky adhesive, there are water-dispersed acrylic resin and one dissolved in an organic solvent. However, although these resin compositions have a high degree of tackiness, it has been difficult to obtain sufficient adhesive strength to substrates such as polyester films and glass. Further, since the adhesive strength is low, there is a problem that peeling occurs due to expansion and contraction of the base material under high humidity and heat.

On the other hand, when the copolyester is used for this purpose, good adhesive strength can be obtained for substrates such as polyester film and glass.
It was difficult to develop tackiness. When using a copolyester to develop tackiness, it is important to lower the glass transition temperature (Tg).
The copolymerization of an aliphatic acid used as a means for lowering the viscosity has the drawback of deteriorating the hydrolysis resistance of the polyester resin itself.

[0005]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a resin composition for tacky-adhesives, which has tackiness, excellent adhesion, and hydrolysis resistance. .

[0006]

Means for Solving the Problems The inventors of the present invention have diligently studied a resin composition for an adhesive to achieve the object of the present invention, and as a result, by introducing a carbonate bond into a copolyester, the tackiness of the adhesive has been improved. It has strength and excellent adhesion,
Further, they have found the present invention to obtain a resin composition for adhesives, which is excellent in hydrolysis resistance, and reached the present invention.

That is, the present invention has the following features. (1) A resin composition for an adhesive, which comprises a polyester having a carbonate bond in the molecule.

(2) The resin composition for adhesives according to (1), wherein a carbonate diol is copolymerized as a diol component of the polyester.

(3) The resin composition for adhesives according to (1) or (2), wherein a diol having a main chain of 3 or more carbon atoms is copolymerized as a diol component of the polyester.

(4) Glass transition temperature of polyester is 0
The resin composition for pressure-sensitive adhesives according to (1) to (3), which has a temperature of not higher than 0 ° C.

(5) When the total amount of each of the dibasic acid component and the diol component of the polyester is 100 mol%, 50 mol% or more of the dibasic acid component is an aromatic dibasic acid. The resin composition for adhesives according to (1) to (4).

(6) The polycarbonate diol has a number average molecular weight of 500 or more (2) to
(5) The resin composition for adhesives according to item (5).

(7) The resin composition for pressure-sensitive adhesives according to (1) to (6), which further comprises using a polyisocyanate or a block thereof as a curing agent.

(8) The resin composition for adhesives according to (1) to (7), which has thixotropic properties.

(9) A laminate using the resin composition for pressure-sensitive adhesive according to (1) to (8).

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The copolyester used in the adhesive resin composition of the present invention must have a carbonate bond in the molecule. By introducing a carbonate bond, hydrolysis resistance is improved and moisture resistance is improved. The method of introducing the carbonate bond into the copolyester is not particularly limited, but can be easily achieved by using, for example, polycarbonate diol as the diol component of the polyester. The polycarbonate diol used at this time has a number average molecular weight of 500 or more,
It is desirable to use those of 600 or more, and most preferably 800 or more. If the number average molecular weight of the polycarbonate diol is less than 500, good adhesion may not be obtained. Polycarbonate diol refers to a compound having the following structure.

[0017]

[Chemical 1]

Although R is a divalent linking group, a hydrocarbon group having a main chain carbon number of 3 or more, preferably 5 or more is desirable. Specific examples thereof include a hexamethylene group, a nonamethylene group, a pentamethylene group, a 3-methylpentamethylene group, a methyloctamethylene group, a cyclohexysandimethylene group and a diphenylpropane group. These polycarbonate diols include (Hexanediol Kasei Co., Ltd. hexanediol carbonate diol "L6002", Toagosei Co., Ltd. "Carbodiol D2000", Asahi Kasei hexanediol / pentanediol carbonate diol "L5651", ( A commercially available product of "Kuraray Polyol C-2050", a hexanediol / 3-methylpentanediol-based carbonate diol manufactured by Kuraray Co., Ltd. can be used. 1-80
Mol% is good. A more preferable lower limit is 3 mol%, and further preferable is 5 mol%. On the other hand, the more preferable upper limit is 80
Mol%, more preferably 60 mol%, most preferably 40 mol%. If the copolymerization amount of the polycarbonate diol is less than 1 mol%, tackiness may not be obtained, and if it is 80 mol% or more, the adhesive strength may be poor.

Polycarbonate diol is used as a raw material for polyester by using a diol having a main chain of 3 or more carbon atoms, preferably 5 or more carbon atoms in the copolyester used in the adhesive / resin adhesive resin composition of the present invention. When one type of glycol component is polymerized at the same time as another glycol, it can be charged all at once. When a main chain carbon number of 2 or less such as ethylene glycol is used as the glycol component, the carbonate bond is cleaved by glycol during the reaction, and is vaporized as ethylene carbonate, for example, and discharged to the outside of the system. It may not be possible to obtain the polyester carbonate. That is, it is preferable not to copolymerize glycol having 2 or less carbon atoms.

Examples of the diol having a main chain of 3 or more carbon atoms which is copolymerized with the polyester used in the present invention include 1,3-propanediol, 1,4-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, 3-methylpentanediol, 1,6-hexanediol, nonanediol, methyloctanediol, neopentyl glycol, diethylene glycol, triethylene glycol, dipropylene glycol, 2-butyl-2-ethyl-1 , 3-propanediol, 2,2
4-trimethyl-1,5-pentanediol, cyclohexanedimethanol, dimer diol, neopentyl glycol hydroxypivalate, ethylene oxide adduct and propylene oxide adduct of bisphenol A, hydrogenated bisphenol A ethylene oxide adduct and propylene oxide There are additions, etc.
Of these, 1,5-pentanediol, 1,6-hexanediol, and 3-methylpentanediol are particularly preferable in terms of hydrolysis resistance and adhesiveness. It should be noted that only one diol having 3 or more carbon atoms in the main chain may be used, or two or more diols may be used in combination.

Further, high molecular weight glycols such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol and polycaprolactone may be copolymerized. Furthermore, after polymerizing the polyester, a lactone or an acid anhydride can be added.

The copolyester used in the present invention preferably has a Tg of 0 ° C. or lower. It is more preferably -5 ° C or lower, and most preferably -10 ° C or lower. On the other hand, the lower limit is not particularly specified, but −80 ° C. or higher is desirable in terms of adhesiveness development. If a polyester having a Tg of more than 0 ° C. is used, good tackiness may not be exhibited.

The copolymerized polyester used in the present invention has 50 mol% or more, preferably 60 mol% of the dibasic acid component, when the total amount of the dibasic acid component and the diol component is 100 mol%. Above, most preferably 6
It is desirable that 5 mol% or more is an aromatic dibasic acid.
If the amount of the aromatic dibasic acid component is less than 50 mol%, the cohesive force of the polyester resin itself cannot be increased, and good adhesive strength may not be exhibited.

Examples of the aromatic dibasic acid component include terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 4,
Aromatic oxycarboxylic acids such as 4'-diphenyl ether dicarboxylic acid, p-oxybenzoic acid and p- (hydroxyethoxy) benzoic acid are mentioned.

Other dibasic acids may be copolymerized with the copolyester used in the present invention. For example, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, dimer acid, cyclohexanedicarboxylic acid, saturated aliphatic or alicyclic dicarboxylic acid such as tetrahydrophthalic anhydride, fumaric acid, maleic acid, maleic anhydride, Unsaturated dicarboxylic acids such as itaconic acid, citraconic acid, and 2,5-norbornene dicarboxylic acid anhydride may be mentioned.

In the copolyester used in the present invention, dicarboxylic acid components other than the above and glycol components such as 5-sodium sulfoisophthalic acid, 5-potassium sulfoisophthalic acid, sodium sulfoterephthalic acid,
2-sodium sulfo-1,4-butanediol, 2,
A sulfonic acid metal salt such as 5-dimethyl-3-sodium sulfo-2,5-hexanediol may be copolymerized within a range that does not impair the effects of the invention. The metal sulfonate base has the effect of significantly improving the dispersibility of inorganic particles such as titanium oxide, talc, pigments, magnetic powder, abrasives and carbon black.

Some of the raw materials for the copolyester used in the present invention include trimellitic anhydride, glycerin,
Trifunctional or higher functional compounds such as trimethylolpropane and pentaerythritol may be used.

In the present invention, the dibasic acid or tricarboxylic acid esterified may be used.

Polyester tree used in the present invention
Examples of methods for determining the composition and composition ratio of fat include poly
Measured by dissolving the ester resin in a solvent such as deuterated chloroform
Do ¹H-NMR and¹³C-NMR, polyester resin
By gas chromatography measured after methanolysis
Quantification, etc. Of these,¹H-NMR
It is simple and preferable.

The lower limit of the number average molecular weight of the copolyester used in the present invention is preferably 2,000, more preferably 3,000. On the other hand, the upper limit is preferably 5000
0, more preferably 30,000, most preferably 250
00. When the number average molecular weight is less than 2000, cohesive force tends to be low and adhesive strength tends to be low. On the other hand, when the number average molecular weight exceeds 50,000, the viscosity of the composition becomes too high, which may make coating and printing on the substrate difficult.

The resin composition of the present invention may further contain a curing agent in order to improve hydrolysis resistance and adhesion strength to the substrate. As the curing agent, an isocyanate compound,
An epoxy compound, an acid anhydride, a melamine compound, a phenol resin, etc. are mentioned. Of these, isocyanate compounds are preferable because they can be cured at low temperatures.

As the isocyanate compound, there are aromatic, aliphatic, and alicyclic diisocyanates, and trivalent or higher polyisocyanates, which may be low molecular compounds or high molecular compounds. For example, tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate or trimer of these isocyanate compounds, and excess of these isocyanate compounds. The amount of the low molecular weight active hydrogen compound such as ethylene glycol, propylene glycol, trimethylolpropane, glycerin, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine or various polyester polyols, polyether polyols, polyamides Conflicts with high molecular weight active hydrogen compounds It includes terminal isocyanate group-containing compounds obtained by.

The isocyanate compound may be a blocked isocyanate. Examples of the isocyanate blocking agent include phenol, thiophenol,
Methylthiophenol, cresol, xylenol, resorcinol, nitrophenol, chlorophenol and other phenols, acetoxime, methylethylketoxime, cyclohexanone oxime and other oximes, methanol, ethanol, propanol, butanol and other alcohols, ethylene chlorohydrin, 1, Halogen-substituted alcohols such as 3-dichloro-2-propanol, t
-Tert-alcohols such as butanol and t-pentanol, lactams such as ε-caprolactam, δ-valerolactam, γ-butyrolactam and β-propyllactam, and other aromatic amines, imides, acetylacetone, Examples also include active methylene compounds such as acetoacetic acid ester and malonic acid ethyl ester, mercaptans, imines, ureas, diaryl compounds such as sodium bisulfite. The blocked isocyanate is obtained by subjecting the above-mentioned isocyanate compound and an isocyanate blocking agent to an addition reaction by a conventionally known appropriate method.

Bisphenol A as an epoxy compound
Diglycidyl ether and its oligomer, hydrogenated bisphenol A diglycidyl ether and its oligomer, orthophthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, terephthalic acid diglycidyl ester, p-oxybenzoic acid diglycidyl ester, tetrahydrophthalic acid Acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,4-butanedioldi Glycidyl ether, 1,6-hexanediol diglycidyl ether and polyalkylene glycol diglycidyl ethers, trime Butyric acid triglycidyl ester, triglycidyl isocyanurate, 1,4-diglycidyloxybenzene, diglycidyl propylene urea, glycerol triglycidyl ether, trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether , Triglycidyl ether of glycerol alkylene oxide adduct, and the like.

Examples of the acid anhydride include pyromellitic dianhydride, cyclohexane-1,2,3,4-tetracarboxylic acid = 3,4-anhydride, ethylene glycol bisanhydrotrimellitate, and 5- (2. 5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, naphthalene 1,8:
Examples include 4,5-tetracarboxylic dianhydride and benzophenone tetracarboxylic dianhydride.

Examples of the melamine compound include formaldehyde or paraformaldehyde alkylated with an alcohol having 1 to 4 carbon atoms such as methanol, ethanol, n-propanol, isopropanol and n-butanol, and urea, N, N-. A condensation product with ethyleneurea, dicyandiamide, aminotriazine, etc., and methoxylated methylol-N, N-
Examples thereof include ethylene urea, methoxylated methylol dicyandiamide, methoxylated methylol benzoguanamine, butoxylated methylol benzoguanamine, methoxylated methylol melamine, butoxylated methylol melamine, methoxylated / butoxylated mixed methylol melamine, and butoxylated methylol benzoguanamine.

Examples of the phenol resin include formaldehyde condensation products of alkylated phenols and cresols. Specifically, alkylated (methyl, ethyl, propyl, isopropyl, butyl) phenol, p-tert-amylphenol, 4,4'-sec-butylidenephenol, p-tert-butylphenol, o-, m-, p -Cresol, p-cyclohexylphenol, 4,4'-isopropylidenephenol, p-nonylphenol, p-octylphenol, 3-pentadecylphenol, phenol,
Examples thereof include formaldehyde condensates such as phenyl o-cresol, p-phenylphenol and xylenol.

The content of these curing agents is preferably 20 parts by weight or less based on 100 parts by weight of the polyester resin,
Although it may be used in the amount of% by weight, the adhesive strength can be further improved by using a curing agent together.

Further, a catalyst may be added to increase the reactivity of these curing agents. Examples of the curing catalyst include tin-based and zinc-based other organometallic compounds, amines, Lewis acids, alkaline compounds and the like. When polyisocyanate or a block thereof is used as a curing agent, among these curing catalysts, tin-based catalysts are preferable for controlling the reaction. As a tin-based curing catalyst, dibutyltin dilaurylate is preferable in terms of versatility. The amount of addition is 10
The lower limit is 0.01 parts by weight, preferably 0.03 parts by weight, based on 0 parts by weight. On the other hand, the upper limit is 20 parts by weight, preferably 10 parts by weight. If it is less than part by weight, the effect as a curing catalyst may not be obtained. On the other hand, if it exceeds 20 parts by weight, the catalytic effect is saturated and it is not economical.

The resin composition for adhesives of the present invention is preferably soluble in a solvent. That is, it is possible to dissolve the above-mentioned polyester resin, curing agent, etc. in a solvent, form a coating film on a substrate sheet by the coating method described below, and dry the solvent with a hot air dryer or the like to use as a tacky adhesive. it can. Solvents used at that time include petroleum aromatic hydrocarbons such as toluene, xylene, Solvesso # 100, # 150, and # 200, ethyl acetate, butyl acetate, methyl cellosolve, ethyl cellosolve, propylene glycol monomethyl ether, propylene glycol monoethyl. Ether, butyl cellosolve, ethyl carbitol, ethyl carbitol, butyl carbitol, 3-methoxy-3-methyl-1-butanol, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, methyl cellosolve acetate , Ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, methoxybutyl acetate, butyl cellosolve acetate, methyl carbitol From acetate, ethyl carbitol acetate, butyl carbitol acetate, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, isophorone, N-methylpyrrolidone, dibasic acid ester, dimethylacetamide, dimethylformamide, γ-butyrolactone, trichlorobenzene, orthodichlorobenzene, etc. It is appropriately selected in consideration of solubility and evaporation rate. Of these, ethyl carbitol acetate, butyl cellosolve acetate, and cyclohesanone are preferable in terms of printability and drying property. At that time, the preferable upper limit of solid content concentration is 80%, preferably 70%.
On the other hand, the lower limit is 20%, preferably 30%. When the solid content concentration is less than 20%, the film thickness of the coating film becomes thin, so that sufficient adhesiveness as an adhesive may not be obtained.
On the other hand, when it is 80% or more, the solution viscosity as a resin composition increases, and good printability may not be exhibited in some cases.

The resin composition for adhesives of the present invention can be coated on a substrate by a known method such as roll coating, gravure coating, screen printing and spray coating. Among these, screen printing is also possible. Is preferable in that thick film printing is possible.

The resin composition for adhesives of the present invention preferably has thixotropy for screen printing.
The thixotropic property referred to here is 25 using a BH type viscometer.
It means that the ratio of the viscosity at 2 rotations and the viscosity at 20 rotations when measured at ± 0.5 ° C is 1.1 or more. If the thixotropy is less than 1.1, good screen printability may not be exhibited. Thixotropy is Aerosil or silica,
It can be added by adding a filler. Of these, a small amount of Aerosil is effective, so
It is preferable because other physical properties such as tackiness and adhesiveness are not impaired. The amount added at this time was 0.
The amount is preferably 1 part by weight or more and 10 parts by weight or less. Addition amount is 10
If the amount is more than 100 parts by weight, the viscosity may be high and the printability may be adversely affected. If the amount is less than 0.1 parts by weight, the effect may be insufficient.

The solvent-soluble pressure-sensitive adhesive composition of the present invention may further contain a leveling agent or a defoaming agent in order to impart screen printability. The leveling agent and / or defoaming agent used include the following. First, as the leveling agent, polyether modified polydimethylsiloxane, polyester modified polydimethylsiloxane, polyester modified methylalkylpolysiloxane, polyether modified polymethylalkylsiloxane, aralkyl modified polymethylalkylsiloxane, polyester modified hydroxyl group-containing polydimethylsiloxane, poly Ether ester modified hydroxyl group-containing polydimethylsiloxane, acrylic copolymer, methacrylic copolymer, vinyl copolymer, polyether modified polymethylalkylsiloxane, acrylic acid alkyl ester copolymer, methacrylic acid alkyl ester copolymer , Acrylic acid, alkyl acrylate copolymer, polyoxyalkylene monoalkyl or alkenyl ether graft copolymer, lecithin, etc. It can be added to things.

The amount of these leveling agents added is 0.05 to 10% by weight of the total weight of the resin composition, and preferably 0.
It is from 07 to 4.0% by weight. If the addition amount is less than 0.05% by weight, the leveling effect may not be obtained,
On the other hand, if it exceeds 10% by weight, the leveling agent may bleed out, which may adversely affect the tackiness and adhesiveness.

As a defoaming agent, a special defoaming agent containing no silicon, an acrylic copolymer, a methacrylic copolymer, a vinyl copolymer, a foaming polymer, a polysiloxane, a foaming polysiloxane, a poly Methylalkylsiloxane,
Known substances such as polyether modified polysiloxane and paraffinic mineral oil can be added.

The amount of these antifoaming agents added is 0.05 to 10% by weight, preferably 0.0
It is 5 to 4.0% by weight. If the addition amount is less than 0.05% by weight, the effect of defoaming may not be obtained, while 10
If it exceeds 5% by weight, bleeding out may occur, which may adversely affect the tackiness and adhesiveness.

In addition to the copolyester, the resin composition of the present invention may contain other resins, if desired. Examples thereof include polyester polyols, polyethers such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol, polycaprolactone, polycarbonate, polyurethane, epoxy resin, acrylic resin, vinyl resin and the like.

The resin composition of the present invention may further contain an inorganic filler such as silica or talc or a pigment, or a rosin-based or acrylic-based tackifier.

[0049]

EXAMPLES The present invention will be specifically described below with reference to examples. In the examples, "parts" means "parts by weight".

Table 1 shows the composition and characteristics of the copolyester resin used in the examples and comparative examples. <Synthesis Example of Polyester (a)> 208 parts by weight of terephthalic acid, 208 parts by weight of isophthalic acid, and pentanediol 39 were placed in a reactor equipped with a stirrer, a thermometer, and a distilling cooler.
0 parts by weight, polycarbonate diol 1 (PCD-1
Asahi Kasei Corporation L6002) 500 parts by weight, tetrabutyl titanate 0.2 parts by weight were added, and 2 at 170 to 220 ° C.
The time esterification reaction was performed. After completion of the esterification reaction,
While raising the temperature of the reaction system from 220 ° C. to 260 ° C., the pressure inside the system was gradually reduced to 500 Pa over 60 minutes. Then, a polycondensation reaction was further performed at 13 Pa or less for 60 minutes to obtain a polyester (a).

The polyester (a) had a composition of 50 mol% of terephthalic acid and 50 mol% of isophthalic acid as a dibasic acid component, 90 mol% of pentanediol as a diol component, and 10 mol% of polycarbonate diol 1. The glass transition temperature is -15 ° C and the number average molecular weight is 20,000.
Met. The polyesters (b) to (e) were manufactured in the same manner as the polyester (a). Since polyesters (d) and (e) are polyesters having no carbonate bond in the molecule, they are comparative synthesis examples. The composition and the measurement results are shown in Table 1. (Numbers are mol% in resin)

[0052]

[Table 1]

The symbols relating to the composition in Table 1 have the following meanings. TPA: terephthalic acid IPA: isophthalic acid SA: sebacic acid EG: ethylene glycol NPG: neopentyl glycol PD: pentanediol HD: hexanediol PCD-1: hexanediol carbonate diol Mn = 2000 (L6002 manufactured by Asahi Kasei Corporation) PCD -2: Nonanediol carbonate diol
Mn = 1000 (PNOC-100 manufactured by Kuraray Co., Ltd.)
0)

The composition of the obtained resin was analyzed by using ¹ H-NMR. The number average molecular weight was measured by gel permeation chromatography using THF as a solvent, and the value in terms of standard polystyrene was measured. Further, the glass transition temperature was measured by using a differential scanning calorimeter, 10 mg of a measurement sample was placed in an aluminum pan, the lid was pressed and sealed, and the temperature range of −150 to 250 ° C. was set to 20.
It was measured at a temperature rising rate of ° C / min.

Example 1 Copolymerized polyester a (50 parts) was added to cyclohexanone (50 parts), and the mixture was heated and dissolved at 80 ° C. for 6 hours with stirring to obtain a transparent varnish. The B type viscosity at 25 ° C. was 400 dPa · s. To 100 parts of this varnish, 1 part of Aerosil # 300 (manufactured by Nippon Aerosil Co., Ltd.) is added as a thixotropic agent.
Section, as a defoaming agent, KS-66 (Shin-Etsu Silicone Co., Ltd.)
0.5 part) and 1 part of MK Conc (manufactured by Kyoeisha Chemical Co., Ltd.) as a leveling agent, stirred well and dispersed with a three-roll mill to obtain an ink. To this ink, 3 parts of Coronate L (tolylene diisocyanate type polyisocyanate manufactured by Nippon Polyurethane Industry Co., Ltd.) as a curing agent,
0.01 part of dibutyltin dilaurylate was added as a curing catalyst and stirred well to obtain a resin composition for adhesive.

Examples 2 and 3 and Comparative Examples 1 and 2 Using the copolyesters synthesized with the raw material compositions shown in Table 1, Examples 2 and 3 and Comparative Examples 1 and 2 were prepared in the same manner as in Example 1. Got The composition of each composition is shown in Table 2.

Comparative Example 3 An aqueous acrylic resin (154 manufactured by ThreeBond Co., Ltd.)
The evaluation results when 9) is used are shown in Table 2 as Comparative Example 3.

The inks obtained in Examples 1 to 3 and Comparative Examples 1 to 3 were screen-printed (125 mesh, stainless steel) on a biaxially stretched polyester film having a thickness of 75 μm so that the thickness after drying was 20 μm. Manufactured, with bias), and dried in an IR furnace at 130 ° C. for 3 minutes to obtain a sample for evaluation. The evaluation was performed as follows. The results are also shown in Table 2. In addition, although Examples 1 to 3 and Comparative Examples 1 and 2 had good printability, Comparative Example 3 was water-based, so the ink was dried during printing and the plate was clogged.
Good continuous printability was not obtained.

Thixotropy The viscosity was measured at 25 ° C. using a BH type viscometer.
It was determined by dividing the viscosity at 2 rotations by the viscosity at 20 rotations.

Tackiness The strength of tackiness was observed by touching the coating film surface of the evaluation sample with a finger. The one with strong tackiness is good. The evaluation criteria are as follows. ◎: Good tackiness (lifts the film without separating from the finger) ○: Tackiness (film lifts but immediately drops) △: Slight tackiness ×: No tackiness

Adhesion Test A 75 μm polyester film was overlaid on the printed surface of the sample for evaluation, and heated and provisionally pressure-bonded at 130 ° C. for 5 seconds with a heat sealing machine (TP-701B-B type) manufactured by Tester Sangyo Co., Ltd. After that, it was heated again at 130 ° C. for 3 minutes in the IR furnace to accelerate the curing reaction. This sample was cut into 1 cm widths, and the adhesive strength when peeled 180 degrees was observed.
The evaluation criteria were as follows. ⊚; ≧ 1 N / cm ◯; 0.5 to 1 N / cm Δ; 0.2 to 0.5 N / cm ×; <0.2 N / cm

Hydrolysis resistance test A sample prepared in the same manner as the sample used for the adhesion test was left under high temperature and high humidity of 60 ° C. × 95% for 1000 hours, and then the adhesive strength when peeled 180 degrees was observed. . The evaluation criteria were as follows. ⊚: Adhesive strength retention rate ≧ 80% ○; 80%> Adhesive strength retention rate ≧ 60% Δ; 60%> Adhesive strength retention rate ≧ 40 ×; 40%> Adhesive strength retention rate

[0063]

[Table 2]

Comparative Examples 1 and 2 are out of the scope of the present invention because the copolyester does not have a polycarbonate bond. In Comparative Example 2, Tg is 0 ° C or higher.
Comparative Example 3 does not use a copolyester, and thus is outside the scope of the present claims.

According to Table 2, the sheets coated with the tacky-adhesive resin compositions shown in Examples 1 to 3 have any of tackiness, adhesive strength and hydrolysis resistance as compared with Comparative Examples 1 to 3. It turns out that it has outstanding performance.

[0066]

INDUSTRIAL APPLICABILITY The present invention has a carbonate bond in the molecule and preferably has a main chain having 3 carbon atoms as a diol component.
The composition containing the polyester obtained by copolymerizing the above-mentioned diols can be used as a transparent touch panel or a keyboard for a computer because it can obtain a tacky adhesive having excellent adhesiveness and hydrolysis resistance while having tackiness. It can be used as a pressure-sensitive adhesive for substrates such as polyethylene terephthalate sheet and polycarbonate sheet, FPC, glass, etc. used for applications such as membranes, or those obtained by depositing ITO on these substrates.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09J 169/00 C09J 169/00 175/06 175/06 F term (reference) 4J029 AA03 AA08 AB01 AC01 AC02 AD01 AD07 AD10 AE13 BA02 BA04 BA05 BA07 BA08 BB13A BD06A BD10 BF17 CB04A CB05A CB06A CB10A CC05A CF08 EB04A EB05A HC03 JC751 JF371 4J034 BA03 DA01 DB04 RA05 JA04 HC05 HC12 HC04 HC12 HC04 HC12 HC22 HC61 HC01 HC22 HC22 HC61 HC12 HC22 HC22 HC61 HC01 HC22 HC22 HC22 HC61 EF331 EL021 HB22 HB44 HC25 KA16 KA25 LA02 LA06 LA07

Claims (9)

[Claims] 1. A resin composition for adhesives, comprising a polyester having a carbonate bond in the molecule. 2. The resin composition for adhesives according to claim 1, wherein a polycarbonate diol is copolymerized as a diol component of the polyester. 3. The resin composition for adhesives according to claim 1, wherein a diol having a main chain of 3 or more carbon atoms is copolymerized as a diol component of the polyester. 4. The resin composition for adhesives according to claim 1, wherein the polyester has a glass transition temperature of 0 ° C. or lower. 5. When the total amount of each of the dibasic acid component and the diol component of the polyester is 100 mol%, 50 mol% or more of the dibasic acid component is an aromatic dibasic acid. Item 4. The resin composition for adhesives according to items 1 to 4. 6. The resin composition for pressure-sensitive adhesives according to claim 2, wherein the polycarbonate diol has a number average molecular weight of 500 or more. 7. The resin composition for pressure-sensitive adhesives according to claim 1, wherein polyisocyanate or a block thereof is used as a curing agent. 8. The resin composition for adhesives according to claim 1, which has thixotropy. 9. A laminate using the resin composition for pressure-sensitive adhesive according to claim 1.