JP2001234150A - Two-liquid type adhesive composition for lamination and lamination method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an excellent two-liquid type adhesive composition for lamination which, when used for producing a composite film including an aluminum foil, cures quickly and can reduce the aging time. SOLUTION: This composition comprises a main component containing a resin having amino groups and an acidic compound and a curing agent containing a polyisocyanate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an adhesive composition and a laminating method. More specifically, a two-component mixed adhesive composition for lamination used in the production of composite films mainly used for packaging materials such as foods, pharmaceuticals, detergents, etc. by laminating various plastic films, metal-deposited films, aluminum foils and the like. About things.

[0002]

2. Description of the Related Art Dry lamination is a technique in which an adhesive is applied to one surface of a material, the solvent is removed by evaporation, and the other material is laminated while being heated and pressed. This technology is
Arbitrary films can be stuck together freely,
Since a composite film having performance according to the purpose can be obtained, it is widely used in the production of food packaging materials that require high performance.

Conventionally, as an adhesive for dry lamination,
Two-component reactive polyurethane adhesives are mainly used. The two-component reactive adhesive is composed of a main component having a hydroxyl group at the polymer terminal (polyol component) and a curing agent having an isocyanate group (polyisocyanate component), and forms a urethane bond by a reaction between the hydroxyl group and the isocyanate group to cure. I do.

[0004] Typical main agents used in practice include polyester polyols having terminal hydroxyl groups obtained from polyols and dicarboxylic acids, polyester polyurethane polyols obtained from polyester polyols and organic diisocyanates, and polyester ether polyols obtained from polyether polyols and organic diisocyanates. Examples thereof include polyether polyurethane polyols, polyester polyether polyurethane polyols obtained from a mixture of polyester polyol and polyether polyol, and organic diisocyanate, and these are all bifunctional to trifunctional polyols.

On the other hand, as a curing agent, an adduct obtained by adding 3 mol of organic diisocyanate to 1 mol of trimethylolpropane, a buret obtained by reacting 1 mol of water with 3 mol of organic diisocyanate, or 3 A polyfunctional organic polyisocyanate having a binding form such as isocyanurate obtained by polymerization of a molar organic diisocyanate is used, and the polyisocyanate is reacted with a polyester polyol, a polyether polyol or, if necessary, a low-molecular polyol by reacting these. The obtained polyurethane polyisocyanate compound is mainly used.

Conventionally, the mixing ratio of the main agent and the curing agent varies depending on the type of the adhesive, but in general, the equivalent ratio of hydroxyl group / isocyanate group is added at a ratio of 1/1 to 1/3, and acetic acid is used as a diluting solvent. Ethyl is added, the solid content is 20-35%,
It is often used with a viscosity of 12 to 20 seconds (Zahn cup # 3).

[0007] However, these adhesives are required to be 40 to 6 hours after lamination in order to completely cure and develop practical physical properties.
Long aging at 0 ° C. for 3 to 5 days is required. In particular, in order to produce a composite film containing an aluminum foil for use in retort packaging materials, it is necessary to use an aliphatic polyisocyanate having a low curing rate for hygiene, and generally at 50 ° C. for 5 days or more. Aging is required. For this reason, there is a problem that the production efficiency for manufacturing the composite film is not improved. This aliphatic polyisocyanate is isophorone diisocyanate (IPDI)
Alternatively, an adduct or isocyanurate of xylylene diisocyanate (XDI) is used alone or as a mixture thereof.

Several proposals have been made to solve these problems. For example, the use of a polyisocyanate having a uretdione group in the molecule as a curing agent to promote curing of a polyol (Japanese Patent Application Laid-Open No. Hei 8-26942)
8) A product obtained by curing a polyfunctional polyol by curing with a polyisocyanate (JP-A-6-2563)
6) A method of accelerating the curing by increasing the crosslink density, such as 6), or a method of accelerating the curing of a polyol and a polyisocyanate using organozinc as a catalyst (JP-A-6-25637)
And the like, a method using a reaction catalyst between a hydroxyl group and an isocyanate group is mainly used. However, even when using these methods, aging at 50 ° C. for 3 to 4 days or more is required when producing a composite film containing an aluminum foil for retort use.

The type in which the terminal amino group resin is cured with polyisocyanate is used in practical use because the reaction between the amino group and the isocyanate group is remarkably rapid, and the two liquids are gelled at the moment of mixing. Is impossible.

With conventional adhesives, it is difficult to achieve rapid curing, especially in a composite film containing an aluminum foil, and such an adhesive has not yet been obtained.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide an adhesive composition and a laminating method using the same to solve the above problems. That is, the present invention relates to an aliphatic polyisocyanate isophorone diisocyanate (IPD) having a slow curing speed as a curing agent.
Adhesive composition and laminating method which can use an adduct or isocyanurate of xylylene diisocyanate (XDI) to achieve a remarkably high curing rate, shorten the aging time and obtain sufficient adhesive properties Is provided.

[0012]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and have reached the present invention. That is, a first configuration of the present invention is a two-part mixed adhesive composition comprising a resin having an amino group, a main agent containing an acidic compound, and a curing agent containing a polyisocyanate.

[0013] By adding an acidic compound to a resin containing an amino group, the pH of the base material is changed from neutral to acidic, and a salt of the amino group and the acid is formed, whereby the reaction rate between the amino group and the isocyanate group is increased. Can be controlled. These two-part mixed adhesive compositions are used by mixing and mixing a main agent and a curing agent in advance.

A first structure of the present invention is a two-part adhesive composition which further comprises a compound which suppresses the reaction between an amino group and an isocyanate group in the above-mentioned base agent or curing agent. The composition of the present invention is an adhesive composition wherein the acidic compound has a boiling point at atmospheric pressure of 150 ° C. or lower. In the laminating step, when the adhesive composition is applied to a substrate and the adhesive is dried with a dryer, the acidic compound contained in the adhesive can be volatilized. As a result, the reaction between the amino group of the main component and the isocyanate group of the curing agent can be remarkably promoted, and the adhesive can be quickly cured after lamination with another base material.

A second structure of the present invention is a laminating method characterized in that the above-mentioned adhesive composition is mixed in advance, applied to a substrate, dried and laminated with another substrate.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As the amino group-containing resin used as a part of the main agent of the present invention, the following resins can be used.

For example, (1) a polyol comprising a polyether polyol or a polyester polyol is prepared by using diisocyanate to obtain an isocyanate group / hydroxyl group of 1.1 / 1.0 to 2.
0 / 1.0 is added and extended to obtain a terminal isocyanate, and a polyamine is used so that amino group / isocyanate group = 1.1 / 1.0 to 2.0 / 1.0. Obtained by addition extension. (2) A polyester having a terminal carboxyl group was prepared by using a polyamine to prepare an amino group / carboxyl group = 1.1 / 1.
One obtained by dehydration condensation elongation so as to be 0 to 2.0 / 1.0. (3) Polyamide resin having terminal amino group (4) Amino terminal amino resin obtained by condensation of polyamine and formaldehyde.

Preferably, (1), (2) and (1)
And a mixture of (2). Examples of such polyether polyols include, for example, polymerization of an oxirane compound such as ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran using, for example, water, ethylene glycol, propylene glycol, trimethylolpropane, and a low molecular weight polyol such as glycerin as an initiator. And polyether polyols obtained by the above method.

The polyester polyol used in the present invention is obtained by reacting a polybasic acid with a polyhydric alcohol.

As the polybasic acid, any known materials can be used. For example, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, maleic anhydride, fumaric acid, 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid , 1,4-
Naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid,
Biphenyl dicarboxylic acid, 1,2-bis (phenoxy)
Ethane-p, p'-dicarboxylic acid and anhydride or ester-forming derivatives of these dicarboxylic acids; p-hydroxybenzoic acid, p- (2-hydroxyethoxy) benzoic acid and ester-forming derivatives of these dihydroxycarboxylic acids, Polybasic acids such as dimer acid can be used alone or in a mixture of two or more. The dimer acid is a product obtained by the Diels-Alder type dimerization reaction of a C18 unsaturated fatty acid such as oleic acid, linoleic acid, etc. ing. A typical one is C18
0 to 5% by weight of monocarboxylic acid, C36 dimer acid 70
-98% and 0-30% by weight of C54 trimer acid.

Any known polyhydric alcohol can be used. Specific examples include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol,
1,6-hexanediol, neopentyl glycol, methylpentanediol, dimethylbutanediol, butylethylpropanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, bishydroxyethoxybenzene, 1, 4-cyclohexanediol, 1,4-cyclohexanedimethanol, triethylene glycol, polycaprolactone diol, dimer diol, bisphenol A, glycols such as hydrogenated bisphenol A, propiolactone, butyrolactone, ε-caprolactone, δ-valerolactone Polyesters obtained by a ring-opening polymerization reaction of a cyclic ester compound such as β-methyl-δ-valerolactone, ethylene glycol Le, diethylene glycol,
Triethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4
Ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, tetrahydrofuran using one or more compounds having two active hydrogen atoms such as butanediol, 1,6-hexanediol and neopentyl glycol as initiators Polyhydric alcohol components such as polyethers obtained by addition polymerization of one or more monomers such as cyclohexylene and the like can be used alone or as a mixture of two or more.

As the diisocyanate for adding and extending these polyols, aromatic diisocyanates (diphenylmethane diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, tolylene diisocyanate, prepolymers of low molecular weight glycols and the above aromatic diisocyanate) can be used. Polymer, etc.);
Aliphatic diisocyanate (prepolymer of low molecular weight glycols such as 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, ethylene glycol, propylene glycol and the above-mentioned aliphatic diisocyanate); Cyclic diisocyanate (isophorone diisocyanate, hydrogenated 4,4'-diphenylmethane diisocyanate, methylcyclohexylene diisocyanate, isopropylidene dicyclohexyl 4,4'-diisocyanate, prepolymer of low molecular weight glycols and the alicyclic diisocyanate, etc.) And mixtures of two or more of these.

In addition-extending with a diisocyanate, a low-molecular-weight polyol having a molecular weight of 200 or less is used in addition to the polyols described above, for the purpose of controlling the molecular weight of polyurethane polyisocyanate and the distribution of hard segments and soft segments. You may mix. Examples of the low molecular weight polyol include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, dipropylene glycol, hexylene glycol, neopentyl glycol, cyclohexanedimethanol, glycerin, and trimethylolpropane.

As the polyamine, ethylenediamine,
1,6-hexamethylenediamine, piperazine, 2,5
-Dimethylpiperazine, isophoronediamine, 4,4 '
-Dicyclohexylmethanediamine, 3,3'-dimethyl-4,4'-dicyclohexylmethanediamine, 1,
Diamines such as 2-cyclohexynediamine, 1,4-cyclohexanediamine, 1,2-propanediamine and polyoxypropylenediamine; diethylenetriamine;
Triamines such as triethylenetetramine and trimethylolpropanepolyoxypropylenetriamine; hydrazines; such as aminoethylethanolamine, aminopropylethanolamine, aminohexylethanolamine, aminoethylpropanolamine, aminopropylpropanolamine and aminohexylpropanolamine; Aminoalkyl alkanolamines;

Depending on the type of the above-mentioned polyamine serving as a terminal of the resin, the solution may become cloudy when an acidic compound is added. Therefore, the above-mentioned aminoalkylalkanolamine is preferable as the polyamine.

As the acidic compound used as a part of the main agent of the present invention, any compound exhibiting acidity can be used. For example, examples of the organic acids include carboxylic acids, sulfonic acids, phenols, enols, thiols, oximes, and acid imides. Examples of the inorganic acids include hydrochloric acid, hydrogen acids, sulfuric acid, nitric acid, phosphoric acids, and oxo acids. Preferably, organic acids such as carboxylic acids or inorganic acids such as phosphoric acids or derivatives thereof can be mentioned.

Such carboxylic acids include acetic acid, butyric acid, propionic acid, valeric acid, oxalic acid, malic acid, tartaric acid, maleic acid, succinic acid, α-hydroxyisobutyric acid,
Pyruvic acid, malonic acid, itaconic acid, isonicotinic acid,
Examples thereof include lactic acid, fumaric acid, gluconic acid, and the above-mentioned polybasic acids.

Further, as the phosphoric acids or derivatives thereof,
Examples of the phosphoric acids or derivatives thereof used herein include phosphoric acids such as hypophosphorous acid, phosphorous acid, orthophosphoric acid, hypophosphoric acid, and the like, for example, metaphosphoric acid, pyrophosphoric acid, tripolyphosphoric acid, polyphosphoric acid, and ultraphosphoric acid. Condensed phosphoric acids such as monomethyl orthophosphate, monoethyl orthophosphate, monopropyl orthophosphate, monobutyl orthophosphate, mono-2-ethylhexyl orthophosphate, monophenyl orthophosphate, monomethyl phosphite, monomethyl phosphite, monoethyl phosphite, phosphorous acid Monopropyl, monobutyl phosphite, mono-2-ethylhexyl phosphite, monophenyl phosphite, di-2-ethylhexyl orthophosphate, diphenyl orthophosphite, dimethyl phosphite, diethyl phosphite, dipropyl phosphite, Dibutyl phosphate, di-2-ethyl phosphite Mono-, di-esterified products such as diphenyl phosphite, mono-, di-esterified products from condensed phosphoric acid and alcohols, for example, the above-mentioned phosphoric acids, for example, those obtained by adding an epoxy compound such as ethylene oxide and propylene oxide, for example, Epoxy phosphates obtained by adding the above-mentioned phosphoric acids to aliphatic or aromatic diglycidyl ethers and the like can be mentioned.

The amount of the acidic compound to be added is such that the hydrogen ion concentration (pH) of the main agent consisting mainly of the resin containing an amino group and the acidic compound is pH = 1 to 8, preferably pH = 3 to 7.
It is good to add so that it becomes. In this case, the hydrogen ion concentration (pH) is determined by adjusting the pH electrode 1076A-10A for a non-aqueous solvent.
C (manufactured by Horiba, Ltd.).

As the acidic compound having a boiling point of 150 ° C. or less at atmospheric pressure, any known acid compound can be used, but acetic acid is preferred.

As the compound for suppressing the reaction between the amino group and the isocyanate group of the present invention, any known compounds can be used, and the above-mentioned phosphoric acids or derivatives thereof are preferable.

Any known polyisocyanate used as a curing agent of the present invention can be used.

Examples thereof include an adduct of the diisocyanate and a polyol, an isocyanurate, a buret, and an allophanate of the diisocyanate.

The adhesive composition of the present invention can be used by adding a polybasic acid anhydride to increase the acid resistance of the adhesive. Examples of polybasic acid anhydrides include, for example, phthalic anhydride, succinic anhydride, hetanoic anhydride, hymic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydraphthalic anhydride, tetraprom Phthalic anhydride, tetrachlorophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenotetracarboxylic anhydride, 2,3,6,7 naphthalenetetracarboxylic dianhydride, 5- (2,5-oxotetrahydrofuryl) -3-methyl-3-cyclohexene-
Examples thereof include 1,2-dicarboxylic anhydride. These polybasic acid anhydrides have the effect of improving the adhesiveness of the adhesive to the aluminum foil, and also include the aluminum foil and acetic acid, particularly when the interface between the aluminum foil and the adhesive is in contact with an organic acid containing acetic acid. It has the effect of inhibiting the formation of salts with organic acids.

In the adhesive composition of the present invention, an adhesion promoter can be used. Examples of the adhesion promoter include a silane coupling agent, a titanate coupling agent, phosphorus and derivatives thereof.

As the silane coupling agent, for example,
γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β (aminoethyl)-
γ-aminopropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N, N-bis (trimethylsilyl) urea,
3-ureidopropyltrimethoxysilane, 3-aminopropyl-tris (2-methoxy-ethoxy-ethoxy) silane, N-methyl-3-aminopropyltrimethoxysilane, triaminopropyl-trimethoxysilane, hexamethyldisilazane And mercaptosilanes such as γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, and γ-mercaptopropyl-methyldimethoxysilane. N-β (aminoethyl)-having a bifunctional amino group to increase the functional group concentration of the amino group
γ-aminopropyltrimethoxysilane can also be used.

As the titanate coupling agent, isopropyl (N-amidoethylaminoethyl) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2,2-dialkyloxy) Methyl-1-butyl) bis (ditridecyl) phosphite titanate, acetoacetic ester titanate, ammonium lactate, titanium lactate, di-isopropoxy-bis- (2,4-pentadionate) -titanium, di- Isopropyl-bis-triethanolaminotitanate and the like can be mentioned.

As the phosphoric acids and derivative compounds of phosphoric acid, those described above can be used.

The adhesive composition of the present invention may be in any form of a solvent type or a non-solvent type. In the case of the solvent type, the solvent is used as a reaction medium when producing the main agent and the curing agent, and is also used as a diluent during coating. Examples of usable solvents include esters such as ethyl acetate, butyl acetate and cellosolve acetate; ketones such as acetone, methyl ethyl ketone, isobutyl ketone and cyclohexanone; ethers such as tetrahydrofuran and dioxane; and aromatic hydrocarbons such as toluene and xylene. , Halogenated hydrocarbons such as methylene chloride and ethylene chloride, dimethyl sulfoxide, dimethyl sulfamide and the like. Of these, it is usually preferable to use ethyl acetate.

In the laminating method of the present invention, the above-mentioned adhesive composition is applied to a substrate by using a gravure coater, a die coater or a lip coater, and after drying, is bonded to another substrate. The coating width of the die coater and the lip coater can be freely adjusted by the deckles attached to both ends of the die or the lip portion. When a volatile acidic compound is used, if the acidic compound volatilizes, the adhesive gels.
H must be maintained between 1 and 8, preferably between 3 and 7.

The amount of the adhesive applied is about 0.5 to 6.0 g / m
² , preferably 1.0 to 4.0 g / m ² .

When the adhesive composition of the present invention is used, after laminating, the adhesive is cured at room temperature or under heating for 6 to 24 hours to exhibit practical physical properties.

[0043]

EXAMPLES Hereinafter, the contents and effects of the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples. In the examples, “parts” means “parts by weight”.

[Preparation Example 1 of the Main Agent] 10.0 parts of terephthalic acid and 27.6 parts of isophthalic acid were placed in a polyester reaction vessel equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, a rectification tube, a water separator, and the like. , 24.5 parts of adipic acid, 10.4 parts of dimer acid (Versadim 228 manufactured by Cognis), 9.4 parts of ethylene glycol, 1 part of neopentyl glycol
8.8 parts, 14.1 parts of 1,6-hexanediol, and 0.03 parts of zinc acetate were charged, and gradually heated so that the upper temperature of the rectification tube did not exceed 100 ° C., to raise the internal temperature to 240 parts.
C. was maintained. When the acid value became 5 mgKOH / g, xylene was added, and xylene was refluxed at the same temperature using a water separator, and the reaction was further continued to an acid value of 2 mgKOH / g or less. The pressure was reduced to 10 mmHg or less, and the mixture was held for 1.5 hours to remove xylene, and the esterification reaction was completed to obtain an intermediate polyester polyol having a hydroxyl value of 28.
8.9 parts of isophorone diisocyanate was added to 100 parts of the obtained intermediate polyester polyol, and
The mixture was heated to ℃ to perform a urethanization reaction until the NCO% became 1.16, to obtain a polyester urethane polyisocyanate. After diluting this with 111.9 parts of ethyl acetate, the temperature was lowered to 40 ° C., and aminoethanolamine (Amino Alcohol EA, manufactured by Nippon Emulsifier Co., Ltd.) was 3.0.
The mixture was added with stirring, and kept at 50 ° C. for about 1 hour.
To obtain a polyurethaneurea resin having a terminal amino group. This is designated as resin L.

To 100 parts of the resin L, 0.9 part of acetic acid was added as an acidic compound to obtain a base material A having a slightly cloudy appearance and a pH of 6.3. The pH was measured using a non-aqueous solvent pH electrode 1076A-10C (Horiba, Ltd.)
Was used for the measurement.

[Preparation Example 2] Polyphosphoric acid 116 (manufactured by Nippon Chemical Industry Co., Ltd.) was used as a compound for suppressing the reaction between an amino group and an isocyanate group with respect to 100 parts of resin L described above. To obtain a main ingredient B having a pH of 5.9 as a liquid having a slightly cloudy appearance.

[Preparation Example 3 of Main Agent] Based on 100 parts of the resin L, 0.5 part of acetic acid was used as an acidic compound, and as a compound for suppressing the reaction between an amino group and an isocyanate group,
0.6 parts of polyphosphoric acid 116 (manufactured by Nippon Chemical Industry Co., Ltd.) was added to obtain a base material C having a slightly cloudy appearance and a pH of 6.1.

[Preparation Example 4] 22.8 parts of terephthalic acid and 22.8 parts of isophthalic acid were placed in a polyester reaction vessel equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, a rectification tube, a water separator, and the like. , 15.8 parts of adipic acid, sebacic acid 1
3.1 parts, 8.3 parts of ethylene glycol, 15.9 parts of neopentyl glycol, 17.5 parts of 1,6-hexanediol, and 0.03 parts of zinc acetate,
The internal temperature was maintained at 240 ° C. by gradually heating the upper temperature of the rectification tube so as not to exceed 100 ° C. Acid value is 30mgKOH
/ G, add xylene, reflux xylene at the same temperature using a water separator, and acid value 25 mgK.
The reaction was further continued to OH / g or less. The pressure was reduced to 10 mmHg or less, and the mixture was kept for 1.5 hours to remove xylene, and the esterification reaction was completed to obtain a polyester having an acid value of 12 mgKOH / g and a terminal carboxyl group. 1.7 parts of anhydrous piperazine was added to 100 parts of the polyester,
The mixture was kept at 220 ° C. for 5 hours, and amidation was continued until the amine equivalent became 0.20 meq / g-nonvolatile content or less. 10 meq /
A g-solution, a polyester polyamide having a terminal amino group having a nonvolatile content of 50% was obtained. This is called resin M.

Polyphosphoric acid 116 (manufactured by Nippon Chemical Industry Co., Ltd.) was used as a compound for suppressing the reaction between an amino group and an isocyanate group with respect to 100 parts of the resin M.
0 parts, pH = liquid with slightly cloudy appearance
6.3 of base compound D was obtained.

[Preparation Example 5 of Main Agent]
0.3 parts of acetic acid as an acidic compound, and polyphosphoric acid 1 as a compound for suppressing the reaction between an amino group and an isocyanate group.
16 (manufactured by Nippon Chemical Industry Co., Ltd.) was added to obtain a base agent E having a slightly cloudy appearance and a pH of 6.5.

[Preparation Example 6] 12.9 parts of terephthalic acid and 27.5 parts of isophthalic acid were placed in a polyester reactor equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, a rectification tube, a water separator, and the like. , 21.9 parts of adipic acid, 10.4 parts of dimer acid (Versadim 228 manufactured by Cognis), 9.4 parts of ethylene glycol, 1 part of neopentyl glycol
8.7 parts, 14.0 parts of 1,6-hexanediol, and 0.03 part of zinc acetate were charged, and the temperature inside the rectification tube was gradually increased to 240 ° C. so as not to exceed 100 ° C.
C. was maintained. When the acid value became 5 mgKOH / g, xylene was added, and xylene was refluxed at the same temperature using a water separator, and the reaction was further continued to an acid value of 2 mgKOH / g or less. The pressure was reduced to 10 mmHg or less, and the mixture was held for 1.5 hours to remove xylene, and the esterification reaction was completed to obtain an intermediate polyester polyol having a hydroxyl value of 32.
With respect to 100 parts of the obtained intermediate polyester polyol, 4.4 parts of isophorone diisocyanate was added and 120 parts.
The mixture was heated to 0 ° C. to carry out a urethanization reaction until the NCO% became substantially 0, to obtain a polyester urethane polyol. This was designated as Main Agent F.

[Curing Agent Preparation Example 1] Takenate D-110 was placed in a flask equipped with a stirrer, a thermometer, and a nitrogen gas inlet tube.
N (manufactured by Takeda Pharmaceutical Co., Ltd.) 100 parts, Takenate D
-140N (manufactured by Takeda Pharmaceutical Co., Ltd.) is mixed with 100 parts, heated to 60 ° C., stirred for 1 hour,
% = 11.4% of a polyisocyanate was obtained. This was designated as curing agent a.

The above-prepared main agent and curing agent were blended as shown in Tables 1 and 2 below, and laminated by the following method, and their adhesive properties were measured.

The above base material, curing agent and ethyl acetate as a diluting solvent were further blended to prepare an adhesive blending liquid having a nonvolatile content of 25% in advance. After that, 100 lines x plate depth 100
Using an engraving grid type gravure roll coater of μm, apply the adhesive so that the coating amount becomes 3.5 g / m ² -non-volatile content.
The film was coated, dried and laminated with an aluminum foil. Further, an adhesive was similarly applied to the aluminum foil surface of the laminate film so as to have a coating amount of 3.5 g / m ² -nonvolatile content, dried, laminated, and then aged at 40 ° C. for 2 days. To make a composite film.

The following films were used for each film. PET film: E-5100 12 μm manufactured by Toyobo Co., Ltd. Aluminum foil: O material 9 μm manufactured by Showa Aluminum Industry Co., Ltd. CPP film: Trefane NO ZK-93K 70 μm manufactured by Toray Synthetic Film Co., Ltd.

The prepared composite film was evaluated by the following evaluation methods. (Curing speed) The above three-layer composite film undergoing aging at 40 ° C. was subjected to infrared spectroscopic analysis to evaluate the curing speed. The aluminum foil / CPP film of the composite film was peeled off, and the CPP to which the adhesive was adhered was evaluated by infrared spectroscopy. The curing rate was evaluated by the percentage of the infrared absorption peak height of the isocyanate group after accelerating at 40 ° C. for one day with respect to the infrared absorption peak height of the isocyanate group in the adhesive immediately after application of the adhesive.
Performed at a rate. That is, the smaller the ratio, the faster the curing.

(Adhesive strength) PE after aging
Using a tensile tester (manufactured by Shimadzu Corporation), a peeling speed of 300 mm / min was set between an aluminum foil / CPP film of a three-layer composite film of T film / aluminum foil / CPP film under an atmosphere temperature of 25 ° C. The tensile strength at the time of peeling by the T-type peeling method was defined as the adhesive strength. The unit of the adhesive strength was N / 15 mm.

(Retort test) 12 mm × 120 mm using the three-layer composite film after aging was completed.
Was prepared, and as contents, 80 g of a pseudo food in which vinegar, salad oil, and meat sauce were mixed at a weight ratio of 1: 1: 1 was filled. The appearance of the pouch after retort sterilization and sterilization in steam at 135 ° C. for 30 minutes was visually evaluated. Depending on the presence or absence of this evaluation,
It is possible to evaluate the hot water resistance and the content resistance of the laminating adhesive. The evaluation results are shown in Tables 1 and 2 below.

[0059]

[Table 1]

[0060]

[Table 2]

[0061]

The use of the two-component adhesive composition for lamination and the laminating method of the present invention is a problem particularly when producing a retort packaging material comprising a composite film containing a metal foil such as an aluminum foil. The long-term aging of the composite film has been significantly shortened.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J040 EF111 EF131 EF141 EF161 EF281 GA13 HA086 HA166 HA226 HA256 HA286 HB22 HB36 HC17 HD03 HD13 JB02 KA17 KA23 LA11 MA10 MB03 NA02 NA08

Claims (4)

[Claims] 1. A two-part adhesive composition for lamination, comprising a resin having an amino group, a main agent containing an acidic compound, and a curing agent having a polyisocyanate. 2. The laminating material according to claim 1, wherein the main agent or the curing agent contains a compound that suppresses a reaction between an amino group and an isocyanate group.
Liquid mixture type adhesive composition. 3. The two-component adhesive composition for lamination according to claim 1, wherein the acidic compound is an acidic compound having a boiling point at atmospheric pressure of 150 ° C. or lower. 4. A laminating method, wherein the adhesive composition according to claim 1 is mixed in advance, applied to a substrate, dried and laminated with another substrate.