JPH0711225A - Polyurethane adhesive composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition for polyurethane adhesive having excellent acid resistance, heat-resistance and hot-water resistance. CONSTITUTION:This composition for a polyurethane adhesive is produced by adding a phosphorus acid or its derivative, an amine compound and an epoxy resin to an organic polyisocyanate and an organic polyol.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polyurethane adhesive composition having excellent acid resistance and hot water resistance. More specifically, it is an adhesive for laminated composite films such as various plastic films and metal foils. The present invention relates to a polyurethane adhesive composition having excellent water resistance.

[0002]

2. Description of the Related Art In recent years, for example, as a packaging material for foods, a multilayer composite film obtained by laminating a plastic film such as polyethylene, polypropylene, nylon, polyester, vinyl chloride and a metal foil such as an aluminum foil into two layers, three layers or four layers. Has been developed and is widely used. It has been proposed to use a composition containing an organic polyisocyanate and an organic polyol mixed with an oxygen acid of phosphorus or its derivative, an epoxy resin and a silane coupling agent to bond these plastic films or metal foils. (Japanese Patent Publication No. 61-4864).
It has also been proposed to use an organic polyisocyanate and an organic polymer polyol in which a polybasic acid anhydride having at least two acid anhydride groups in the molecule is blended (JP-A-61-47775). Further, it has been proposed to use an organic polyisocyanate, an organic polyol in which an oxygen acid of phosphorus or its derivative, a carboxylic acid compound or its anhydride and an epoxy resin are blended (JP-A-2-84482).

[0003]

However, the packaging material using the above-mentioned adhesive has a drawback that the adhesive force is not always sufficient and the heat resistance or the chemical resistance such as acid resistance and alkali resistance is poor. For example, when a highly acidic food containing free fatty acid is packaged and sterilized by high temperature hot water at 135 ° C. or higher and a long-term storage test is performed, not only the adhesive strength between the metal foil and the plastic film is lowered, but also the packaging material. As a result, it has the drawback that it completely peels off and induces pinholes in the metal foil when it is excessively low, reducing the air barrier property of the metal itself, and the purpose of long-term storage of food is not achieved. . Furthermore, when packaging highly acidic foods with a high content of vinegar or free fatty acids, the adhesive strength is reduced during long-term storage and the plastic film peels off from the metal foil without performing a high temperature sterilization process such as boiling or retort. There was a drawback.

[0004]

As a result of various studies to solve these drawbacks, the present inventors have found that an organic polyisocyanate and an organic polyol are mixed with an oxygen acid of phosphorus or its derivative, an amine compound and an epoxy resin. It was found that a polyurethane adhesive composition having extremely excellent adhesive strength, acid resistance and hot water resistance can be obtained by the method known in the art, and based on this finding, the present invention was completed. I arrived. That is, the present invention relates to a polyurethane adhesive composition obtained by blending an organic polyisocyanate, an organic polyol, an oxygen acid of phosphorus or its derivative, an amine compound and an epoxy resin.

Examples of the organic polyisocyanate used in the present invention include trimethylene diisocyanate,
Tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,
2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate,
Aliphatic diisocyanates such as 1,3-butylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, for example 1,3-cyclopentane diisocyanate 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), methyl 2,4-
Alicyclic diisocyanates such as cyclohexane diisocyanate, methyl 2,6-cyclohexane diisocyanate, 1,4-bis (isocyanatomethyl) cyclohexane, 1,3-bis (isocyanatomethyl) cyclohexane, such as m-phenylene diisocyanate,
p-phenylene diisocyanate, 4,4′-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, 4,4′-diphenylmethane diisocyanate,
Aromatic diisocyanates such as 2,4- or 2,6-tolylene diisocyanate or mixtures thereof, 4,4'-toluidine diisocyanate, dianisidine diisocyanate, 4,4'-diphenyl ether diisocyanate, 1,3- or 1,4- Aroaliphatic diisocyanates such as xylylene diisocyanate or a mixture thereof, ω, ω'-diisocyanate-1,4-diethylbenzene 1,3- or 1,4-bis (1-isocyanate-1-methylethyl) benzene or a mixture thereof,
Triphenylmethane-4,4 ', 4 "-triisocyanate, 1,3,5-triisocyanate benzene, 2,4,6
-Triisocyanate organic triisocyanate such as toluene, 4,4'-diphenyldimethylmethane-2,2 '
Polyisocyanate monomer such as organic tetraisocyanate such as -5,5'-tetraisocyanate, dimer, trimer, biuret, allophanate, carbon dioxide gas derived from the above polyisocyanate monomer and the above polyisocyanate monomer The resulting polyisocyanate having a 2,4,6-oxadiazinetrione ring,
For example ethylene glycol, propylene glycol,
Butylene glycol, hexylene glycol, neopentyl glycol, 1,6-hexane glycol, 3-methyl-1,5-pentanediol, 3,3'-dimethylolheptane, cyclohexanedimethanol, diethylene glycol, triethylene glycol, dipropylene Molecular weight of glycol, glycerol, trimethylolpropane, pentaerythritol, sorbitol, etc. 200
Or an adduct with a low molecular weight polyol of less than, for example, a polyester polyol having a molecular weight of about 200 to 200,000 described later, a polyether polyol, a polyesteramide polyol, a polycaprolactone polyol,
Polyvalerolactone polyol, acrylic polyol,
Examples thereof include adducts such as polyhydroxyalkane and castor oil.

The organic polyol used in the present invention has a functional group number of about 2-6, preferably about 2-4, and a molecular weight of about 200-200,000, preferably about 300-.
100,000, more preferably about 300-50,000
And the acid value is about 0 to 280, preferably about 0 to 100, more preferably 0 to 50 mg KOH / g. More specifically, polyester polyol, polyether polyol, polyester amide polyol, acrylic polyol, polyhydroxyalkane, castor oil,
Examples include polyurethane polyols and mixtures thereof. Examples of such polyester polyols include dibasic acids such as terephthalic acid, isophthalic acid, adipic acid, azelaic acid, sebacic acid or dialkyl esters thereof or mixtures thereof with ethylene glycol, propylene glycol, diethylene glycol, butylene glycol, Neopentyl glycol, 1,6-hexane glycol, 3-methyl-1,5
-Pentanediol, polyester polyol or polycaprolactone obtained by reacting with glycols such as 3,3'-dimethylolheptane, polyoxyethylene glycol, polyoxypropylene glycol, polytetramethylene ether glycol, or mixtures thereof, Examples thereof include polyester polyols obtained by ring-opening polymerization of lactones such as valerolactone and poly (β-methyl-γ-valerolactone).

Examples of polyether polyols include oxirane compounds such as ethylene oxide, propylene oxide, butylene oxide and tetrahydrofuran, and low molecular weight polyols such as water, ethylene glycol, propylene glycol, trimethylolpropane and glycerin as an initiator. An example is a polyether polyol obtained by polymerization. An example of the polyesteramide polyol is obtained by using an aliphatic diamine having an amino group such as ethylenediamine, propylenediamine and hexamethylenediamine as a raw material in the polyesterification reaction. Examples of acrylic polyols include polymerizable monomers having one or more hydroxyl groups in one molecule, such as hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate and the like, or their corresponding methacrylic acid derivatives.
For example, it can be obtained by copolymerizing acrylic acid, methacrylic acid or its ester. Examples of polyhydroxyalkanes include liquid rubbers obtained by copolymerizing butadiene or butadiene with acrylamide. The polyurethane polyol is a polyol having a urethane bond in one molecule, for example, a polyether polyol or polyester polyol having a molecular weight of about 200 to 5,000 and the above-mentioned organic polyisocyanate having an NCO / OH of less than about 1, preferably. Can be obtained by reacting at about 0.8 or less. Further, in addition to the polyols described so far, a low molecular weight polyol having a molecular weight of 62 to 200 may be mixed for the purpose of adjusting the average molecular weight of the polyol component. Examples of these low-molecular weight polyols include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, dipropylene glycol, hexylene glycol, neopentyl glycol, glycols used in the production of polyester polyols such as cyclohexanedimethanol, glycerin, Examples include polyols such as trimethylolpropane and pentaerythritol.

In the present invention, an oxygen acid of phosphorus or its derivative, an amine compound and an epoxy resin are blended with the adhesive composition consisting of the above organic polyisocyanate and organic polyol. Of the phosphorus oxyacids and derivatives thereof used in the present invention, the phosphorus oxyacid may be any one having at least one free oxygen acid, such as hypophosphorous acid and hypophosphorous acid. Examples thereof include phosphoric acids such as phosphoric acid, orthophosphoric acid and hypophosphoric acid, and condensed phosphoric acids such as metaphosphoric acid, pyrophosphoric acid, tripolyphosphoric acid, polyphosphoric acid and ultraphosphoric acid. Examples of the phosphorus oxyacid derivative include those obtained by partially esterifying the phosphorus oxyacid with alcohols in the state where at least one free oxygen acid remains.
These alcohols include methanol, ethanol,
Examples thereof include aliphatic alcohols such as ethylene glycol and glycerin, and aromatic alcohols such as phenol, xylerol, hydroquinone, catechol, and phlorogricinol. The oxygen acid of phosphorus or its derivative may be used alone or in combination of two or more. The amount of phosphorus oxyacid or its derivative added is about 0.0 based on the total composition.
1 to 10% by weight, preferably about 0.05 to 5% by weight, more preferably about 0.1 to 1% by weight.

The amine compound used in the present invention may be any one having at least one primary, secondary or tertiary amino group in the molecule. For example, a non-aromatic amine compound is used. , Mono (di, tri) butylamine, mono (di, tri) ethanolamine, aliphatic amines such as ethylenediamine, alicyclic amines such as cyclohexylamine, heterocyclic amines such as morpholine, piperidine, piperazine, and the like. Examples of the aromatic amine compound include aromatic amines such as aniline, toluidine, anisidine, and phenylenediamine, and aromatic heterocyclic amines such as pyridine, aminomethylpyridine, and imidazole. In addition, examples thereof include aminosilanes such as γ-aminopropyltriethoxysilane and N-β (aminomethyl) γ-aminopropyltriethoxysilane, and these may be used alone or in combination of two or more. Further, these amine compounds may be contained in a state of being chemically bonded to an oxirane compound such as ethylene oxide, propylene oxide, butylene oxide, or an epoxy resin described later. The amount of the amine compound added is about 0.
01-10% by weight, preferably about 0.05-5% by weight,
More preferably, it is about 0.1 to 1% by weight. The epoxy resin used in the present invention is a reaction product of a polyhydric phenol such as bisphenol A or tetrahydroxydiphenylethane and a polyfunctional halohydrin such as epichlorohydrin and has a molecular weight of about 320.
~ 200,000, preferably about 320-4,000 are used. The amount of epoxy resin is about 0.1-50% by weight, preferably about 1-30, based on the total adhesive composition.
% By weight. The polyurethane adhesive composition of the present invention,
Furthermore, in order to improve the performance, a carboxylic acid compound or its anhydride and a silane coupling agent may be added if necessary.

The carboxylic acid compound or its anhydride may be any compound having at least one carboxyl group in the molecule, and examples thereof include acetic acid, lactic acid, propionic acid, oleic acid, succinic acid, maleic acid and phthalic acid. , Pyromellitic acid, benzophenone tetracarboxylic acid, 2,
3,6,7-naphthalene tetracarboxylic acid, 5- (2,5
-Dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid and other mono- or polycarboxylic acids, or anhydrides thereof, which may be used alone or in combination of two or more. May be. These carboxylic acid compounds or their anhydrides may be contained in a state of being chemically bound to a polyol component or an epoxy resin, or may be contained in a state of being simply mixed without being chemically bound. Good. The amount of the carboxylic acid compound or its anhydride added is about 0.01 to 20% by weight, preferably about 0.05 to 10% by weight, more preferably about 0.1 to 5% by weight, based on the total composition. Is.

As the silane coupling agent, the structural formula R-Si≡ (X) ₃ or R-Si≡ (R ') (X) ₂ (wherein R is
Is an organic group having a vinyl group, an epoxy group, an amino group, an imino group or a mercapto group, R'is a lower alkyl group, and X is a methoxy group, an ethoxy group or a chloro atom. , Chlorosilanes such as vinyltrichlorosilane, n- (dimethoxymethylsilylpropyl) ethylenediamine, n-
Examples thereof include aminosilanes such as (triethoxysilylpropyl) ethylenediamine, epoxysilanes such as γ-glycidoxypropyltrimethoxysilane and γ-glycidoxypropyltriethoxysilane, and vinylsilanes such as vinyltriethoxysilane. The amount of the silane coupling agent added is preferably about 0.1 to 5% by weight based on the total adhesive composition. Further, in addition to the silane coupling agent, for example, an additive such as an antioxidant, an ultraviolet absorber, an anti-hydrolysis agent, an antibacterial agent, a thickener, a plasticizer, a pigment or a filler is used as required. be able to. Also,
Known catalysts, additives and the like can be used to control the curing reaction.

The polyurethane adhesive composition of the present invention is preferably used as a two-pack type, but can be used as a one-pack type in some cases. That is, in the case of a two-pack type, an organic polyisocyanate is used as a curing agent, and a main component obtained by mixing a phosphorus oxygen acid or its derivative, an amine compound and an epoxy resin in a polyol component is used as an NCO / O.
Mix just before use so that H is about 0.4-10, preferably about 0.5-2.0. In the case of a one-pack type, a mixture of an organic polyol and an epoxy resin and an organic polyisocyanate are obtained by reacting an excess of an isocyanate group with respect to a hydroxy group in a polyol component, and oxygen of phosphorus. It is obtained by adding an acid or its derivative and an amine compound. This is a type that cures and bonds by reacting with water or moisture in the air. In producing a one-pack type, an isocyanate group (N
The reaction of CO) with the hydroxyl groups (OH) in the polyol and epoxy resin has an NCO / OH of about 1.2 to 2
It is convenient to carry out at 0, preferably about 1.5-10. If the NCO / OH is less than 1.2, the viscosity of the composition is too high, and gelation may occur in some cases. Also, NC
When O / OH exceeds 20, the curability is poor and sufficient adhesive strength may not be obtained. The reaction is usually carried out at about 30 ° C to 100 ° C, and if desired, an organometallic catalyst, a tertiary amine catalyst and the like may be added.

Generally, the two-component type has a faster curing rate than the one-component type, has excellent adhesive performance, and has a wide range of applications. In addition, although the two-component type has a short pot life, it automatically supplies the main agent and the curing agent from separate systems in a predetermined amount ratio by the minimum amount necessary for coating,
It can be used without any trouble by using a device that can be mixed immediately before use. The adhesive composition of the present invention has a temperature of room temperature to 140 ° C., preferably room temperature to 100 ° C.
0-10,000 cps, preferably about 100-5,000 cs
When it has a viscosity of ps, it can be used in a solventless form. When the viscosity is higher than the above range, it may be diluted with an organic solvent in either one-component type or two-component type. As the organic solvent, for example, any ester solvent such as ethyl acetate, ketone solvent such as methyl ethyl ketone, aromatic solvent such as toluene and xylene, etc. may be used as long as it is inert to isocyanate groups. As a specific formulation using the polyurethane adhesive composition of the present invention, for example, the adhesive composition was applied to the film surface by a solvent type or solventless type laminator, and in the case of a solvent type, the solvent was volatilized. After that, in the solventless type, the adhesive surface is directly stuck and the composition is cured at room temperature or under heating. Normal,
Coating weight of about 1.0 to 2.0 g / m ² in the solvent-free type, a solvent type is advantageous to use in about 2.0~5.0g / m ^2. The adhesive composition of the present invention cures faster than conventional urethane adhesives and has excellent adhesive properties, and particularly polyethylene terephthalate, nylon, polyethylene, polypropylene, plastic films such as vinyl chloride, aluminum, silicon oxide, and nitride. It has excellent adhesive strength, heat resistance, water resistance, and chemical resistance to plastic films deposited with silicon, etc., and metals such as stainless steel, iron, copper, and lead.

[0014]

The polyurethane adhesive composition of the present invention is
By combining an oxygen acid of phosphorus or its derivative, an amine compound and an epoxy resin with an adhesive composition consisting of an organic polyisocyanate and an organic polyol, for example, a metal foil such as an aluminum foil and polyethylene can be used as an adhesive for food packaging materials. It exhibits excellent adhesive strength, heat resistance, and hot water resistance between plastic films such as polypropylene, nylon, and polyethylene terephthalate, and even if it is sterilized by high temperature hot water at 135 ° C or higher with food packed in the packaging material. It can be advantageously used as a packaging material which has good acid resistance without peeling between the foil and the plastic film and also has good long-term storage stability of food.

[0015]

EXAMPLES Next, the present invention will be described more specifically with reference to Examples and Comparative Examples. All% in the examples mean% by weight. Example 1 194.2 g of dimethyl terephthalate, 248.3 g of ethylene glycol and 0.2 g of zinc acetate were added under a nitrogen stream to give 160
The transesterification reaction was carried out at ˜220 ° C. After distilling out the required amount of methanol, add 83.1 g of isophthalic acid,
The esterification reaction is carried out at ˜220 ° C., and after distilling a predetermined amount of water, 282.3 g of azelaic acid is added.
Perform esterification reaction at ℃, gradually reduce the pressure to 220-2
220-230 at 1-2 mmHg after condensation for 60 minutes at 30 ° C
Condensation was carried out at 4 ° C. for 4 hours. A polyester glycol having a number average molecular weight of about 15,000 was obtained. (Used as polyol A)
50 g of this polyol A was dissolved in 67 g of ethyl acetate,
Then, 2 g of phthalic anhydride, 0.1 g of phosphoric acid, 0.1 g of morpholine, and 15 g of Epicoat 1002 (epoxy resin manufactured by Shell Chemical Co., Ltd.) were added to obtain a main component A having a solid content of 50%.

Example 2 To 50 g of polyol A was added 2 g of maleic anhydride,
What was reacted at 0 ° C. for 3 hours was dissolved in 67 g of ethyl acetate, and then 0.1 g of phosphoric acid, 0.15 g of triisopropanolamine and 15 g of Epikote 1002 were added,
Main agent B having a solid content of 50% was obtained. Example 3 A polyester glycol having a number average molecular weight of 16000 and comprising isophthalic acid / terephthalic acid / azelaic acid = 2/4/5 (molar ratio) and ethylene glycol was obtained according to the method for producing the polyol A. (Polyol B) To 40 g of this polyol B, 0.1 g of succinic anhydride was added.
What was reacted at 0 ° C. for 2 hours was dissolved in 75 g of ethyl acetate, and then 0.1 g of phosphoric acid, 0.1 g of morpholine and 10 g of Epikote 1002 were added to prepare a main agent C having a solid content of 40%.
Got Example 4 A polyester glycol having a number average molecular weight of 2500 and comprising isophthalic acid / sebacic acid = 1/1 (molar ratio) and ethylene glycol / neopentyl glycol = 1/3 (molar ratio) was obtained according to the method for producing the polyol A. (As Polyol C). A mixed solution of 100 g of polyol C, 6.2 g of isophorone diisocyanate, 106.2 g of ethyl acetate, and 0.05 g of dibutyltin dilaurate was reacted at 65 ° C. for 7 hours, then 0.5 g of diethylene glycol was added, and the mixture was further reacted for 1 hour. Then 0.1 g of phosphoric acid and 0.1 of dibutylamine
g, Epicoat 1002 15 g, and ethyl acetate 15 g were added to obtain a polyester urethane type main agent D having a solid content of 50%.

Example 5 2 g of succinic anhydride was added to 50 g of polyol A to prepare 140
What was reacted for 3 hours at ℃ was dissolved in 67 g of ethyl acetate,
Then, phosphoric acid 0.1 g, N, N ', N ", N"'-tetra (2
-Hydroxypropyl) ethylenediamine (0.5 g) and Epicoat 1002 (15 g) were added to obtain a main component E having a solid content of 50%. Example 6 Isophorone diisocyanate trimer having an NCO group content of 17.3% (T1890 / 100; manufactured by Huls Co.) 1
00 g was dissolved in 100 g of ethyl acetate to obtain a polyisocyanate solution having a solid content of 50%. Hereinafter, this solution is referred to as curing agent A. Example 7 188.2 g of xylylene diisocyanate was heated to 90 ° C., and 44.7 g of trimethylolpropane was gradually added and reacted for 2 hours. Next, 77.6 g of ethyl acetate was added and mixed uniformly to give a solid content of 75% and an NCO group content of 13.5%.
A solution of polyisocyanate having a viscosity of 1800 cps at 25 ° C. was obtained. Hereinafter this solution is referred to as a curing agent B. Example 8 A mixed solution of 174.2 g of tolylene diisocyanate, 44.7 g of trimethylolpropane and 73.0 g of ethyl acetate was reacted at 65 ° C. for 3 hours. A solution of polyisocyanate having a solid content of 75%, an NCO group content of 14.4% and a viscosity of 1000 cps at 25 ° C. was obtained. Hereinafter, this solution is referred to as a curing agent C. Adhesive compositions 1 to 8 were prepared by blending the thus obtained main components A to E, curing agents A to C and silane coupling agents as described in [Table 1] below. For comparison, main components A'to D'containing no amine compound, phosphoric acid, carboxylic acid compound or its anhydride and epoxy resin were produced as shown below and blended as shown in [Table 2]. Then, the adhesive compositions 51 to 55 were prepared.

Comparative Example (1) In exactly the same manner as in Example (1), a main agent A ′ having a solid content of 50% except for morpholine was obtained. (2) In exactly the same manner as in Example (2), a main agent B ′ having a solid content of 50% except maleic anhydride was obtained. (3) In exactly the same manner as in Example (3), a main agent C ′ having a solid content of 40% except for phosphoric acid was obtained. (4) In the same manner as in Example (4), a main agent D ′ having a solid content of 50% except for the epoxy resin was obtained. After using each of the adhesive compositions shown in [Table 1] and [Table 2] to prepare a composite film by the method described below, the adhesive strength between the plastic film and the aluminum foil, the hot water and the acid resistance of the respective films were prepared. The test was conducted. The results are shown in [Table 3] and [Table 4].

Preparation of three-layer composite film Composite film: polyethylene terephthalate film (thickness 12μ) / aluminum foil (thickness 9μ) / unstretched polypropylene (thickness 70μ, surface corona treatment) The above composite film was prepared by the following method. did. That is,
Each of the adhesive compositions shown in [Table 1] was first applied to a polyethylene terephthalate film by a laminator at room temperature, and those containing a solvent were volatilized, and then the applied surface was bonded to the aluminum foil surface. Then, the adhesive composition was applied to the other surface of the aluminum foil of the composite film in the same manner, and the solvent-containing material was volatilized and the applied surface was laminated with the unstretched polypropylene. Then, these laminated films were kept warm at 50 ° C. for 3 days to cure the adhesive composition.

Adhesion test 300 mm x from the composite film prepared as described above
Using a test piece of 15 mm in size, using an Instron type tensile tester, peeling speed by T-type peeling 300 mm /
The adhesive strength was measured in minutes. The measured value is the adhesive strength (g / 15m) between the aluminum foil and the unstretched polypropylene.
m) is shown as an average value of 5 test pieces. Heat-resistant water and acid-resistant test Using each composite film, a bag having a size of 13 cm x 17 cm was prepared. Vinegar having a concentration of 4.2% or more was filled as the content. This bag was sterilized with hot water under a pressure of 4.5 kg / cm ² at 135 ° C. for 30 minutes, and then the peeled state between the aluminum foil and the polypropylene film, the adhesive strength and the peeled state after storing at 60 ° C. for 14 days I checked. In addition, the peeled state was similarly examined in a system not subjected to hot water sterilization. The test was conducted on 5 bags each. The results listed in the table are their average values. From the above results, the hot water resistance and acid resistance of the adhesive composition are remarkably improved by the addition of the oxygen acid of phosphorus or its derivative, the amine compound and the epoxy resin. Therefore, the adhesive composition of the present invention has a high It can be seen that it is excellent as an adhesive for a composite laminate film for producing a packaging material for a retort food containing an acidic food.

[0021]

[Table 1]

[Table 2]

[0022]

[Table 3]

[Table 4]

Claims (10)

[Claims] 1. A polyurethane adhesive composition comprising an organic polyisocyanate, an organic polyol and an oxygen acid of phosphorus or its derivative, an amine compound and an epoxy resin. 2. The polyurethane adhesive composition according to claim 1, wherein an oxygen acid of phosphorus or its derivative, an amine compound and an epoxy resin are mixed with an organic polyol. 3. The polyurethane adhesive composition according to claim 1, further comprising a carboxylic acid compound or an anhydride thereof. 4. The polyurethane adhesive composition according to claim 1, further comprising a silane coupling agent. 5. The polyurethane adhesive composition according to claim 1, wherein the organic polyisocyanate is an aliphatic polyisocyanate. 6. The polyurethane adhesive composition according to claim 1, wherein the organic polyol is a polyester polyol. 7. The polyurethane adhesive composition according to claim 1, wherein the oxygen acid of phosphorus is phosphoric acid. 8. The polyurethane adhesive composition according to claim 1, wherein the amine compound is a non-aromatic amine compound. 9. The polyurethane adhesive composition according to claim 1, wherein the epoxy resin is a reaction product of a polyhydric phenol and a polyfunctional halohydrin. 10. A retort pouch obtained by bonding with the polyurethane adhesive composition according to claim 1.