JP2002003813A - Adhesive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an adhesive composition that has an increased adhesion strength between a metal foil and a plastic film, can prevent the generation of poor appearance as a food packaging material caused by inadvertent bending after retorting, does not decrease the adhesion strength and does not generate pin holes with time even when various foods are packed, and can maintain a high adhesion strength for a long time. SOLUTION: Composition (I) comprising a mixture of an organic polyol and a phosphorus oxyacid or a derivative thereof, and a composition (II) comprising a mixture of an organic polyisocyanate and a silane coupling agent are blended together.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a urethane-based adhesive composition, and more particularly, to a urethane-based adhesive composition for laminated composite films composed of various plastic films, metal foils, metal-deposited films, etc. having excellent hot water resistance and acid resistance. The present invention relates to a urethane-based adhesive composition.

[0002]

2. Description of the Related Art Conventionally, as a material for food packaging, medical product packaging, and cosmetic packaging, for example, a multilayer composite film obtained by laminating a plastic film such as polyethylene, polypropylene, nylon, or polyester, a metal-deposited film, or a metal foil such as an aluminum foil. Is widely used. A urethane-based adhesive combining an organic polyol and an organic isocyanate for bonding these plastic films, metal-deposited films, metal foils, and the like is known. In recent years, for food packaging containing vinegar, free fatty acids, etc.,
Urethane-based adhesives with improved conventional adhesive performance have been provided.

[0003] For bonding these plastic films or metal foils, for example, a composition containing an organic polyol and an organic isocyanate is mixed with an oxygen acid of phosphorus or a derivative thereof, an epoxy resin, and a silane coupling agent. Adhesive (JP-B-61-4864), an adhesive obtained by blending an organic polyisocyanate, an organic polymer polyol with an oxygen acid or a derivative of phosphorus, a carboxylic acid compound or an anhydride thereof, and an epoxy resin (JP-A-2-84482) It has been proposed to use an organic polyol having a carboxyl group at the molecular terminal, an orthophosphoric acid or an ester compound thereof, and an adhesive (JP-A-5-51574) containing a silane coupling agent.

[0004] However, in the multilayer composite film of the metal foil laminate of the packaging material, the multilayer composite film is often used so that the metal foil is near the inner layer side of the packaging container. The main purpose is to improve the water resistance, acid resistance, etc. on the inner layer side of a metal foil such as aluminum, and the adhesiveness, heat resistance, oil resistance, etc. on the outer layer side of a metal foil such as aluminum. It is not intended to improve. In addition, for applications represented by retort pouches with conventional adhesives, adhesion to metal foils such as aluminum is not sufficient,
In many cases, different adhesives are used on the outside of the metal foil and on the inside of the metal foil, and it has been desired from the economical viewpoint that the same adhesive can be used for processing. In many cases, conventional proposals focus on the modification of organic polyols, the oxygen acid or derivative of phosphorus, and the type of silane coupling agent. Nothing pays attention to the use of the composition divided into the compositions described above.

[0005] On the other hand, especially in the field of food packaging, along with the trend of improving the eating habits and simplicity, the food to be filled can be filled with various kinds of sauces, soy sauce, vinegar, animal oils and fats, various spices, alcohol I do not know that diversification of inclusions and the like and their combinations will stop. Food sterilization temperature is 100
C. (boil), 120.degree. C. (retort), and 135.degree. C. (high retort), and strict performance such as water resistance, oil resistance, and acid resistance at high temperatures is required for laminated films. At the same time, the configuration, shape and shape of the retort pouch
The size and content are becoming more complex and this trend is likely to continue to grow.

[0006]

In recent years, the heat sterilization time has been shortened for the purpose of altering and protecting the contents, and in order to efficiently raise the temperature of the contents to the target temperature in a short time,
Rotating retorts, spray retorts and shower retorts have been devised and implemented. However, in such a heat sterilization, if a conventional adhesive is used, it is mainly used for business use, and it is 1k.
If the retort requires high-temperature sterilization in a four-layer configuration containing a nylon film and a large bag exceeding g,
During retort rotation or stacking work after retort, or spray retort or shower retort subject to local distortion, undesired bending may cause partial appearance failure and between nylon film and aluminum foil Peeling occurs, and during work such as stacking after the above retort, when the laminating strength of the aluminum foil and the sealant film is reduced, a bag break occurs, and when the content is filled with a highly acidic food or oily food, the In many cases, a problem such as a decrease in adhesive strength or generation of pinholes occurs.

[0007] The present invention can improve the adhesive strength between a metal foil and a plastic film, and prevent appearance defects caused by undesired bending after retorting as a food packaging material.
In addition, even when filled with high-acid foods or oily foods, there is no decrease in adhesive strength over time or the occurrence of pinholes, and it is an object of the present invention to provide an adhesive composition that can maintain strong adhesive strength over a long period of time. Is what you do.

[0008]

Means for Solving the Problems The present inventors have conducted various studies to solve the above problems, and as a result, have found that organic polyols, silane coupling agents, and organic polyols conventionally used as components of the above-mentioned adhesive composition. Isocyanate and phosphorus oxyacids or derivatives thereof are divided into a group containing a silane coupling agent and two groups containing phosphorus oxyacids or derivatives, and after preliminarily mixing the two components belonging to those groups, It has been found that the object of the present invention can be achieved by compounding the group of the above, and the present invention has been achieved.

That is, the present invention provides a composition (I) comprising a mixture of an organic polyol and an oxygen acid of phosphorus or a derivative thereof.
And a composition comprising a composition (II) in which an organic polyisocyanate and a silane coupling agent are mixed, and a urethane-based adhesive composition. Further, the composition of the present invention is characterized in that the composition (I) is obtained by further mixing an epoxy resin. Further, the composition of the present invention comprises a composition (II)
Is characterized by being further mixed with an epoxy resin. Further, the composition of the present invention is characterized in that the organic polyol is an organic polyol containing a carboxyl group in a molecule.

[0010] The present invention further provides a laminated film laminate formed by bonding with the above composition.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The organic polyol used in the present invention has a number of functional groups in one molecule of about 2 to 6, preferably about 2 to 4, and a number average molecular weight of about 500 to 100,000.
0, preferably 1,000 to 30,000 compounds. More specifically, polyester polyols, polyether polyols, polyether ester polyols, polyester amide polyols, acrylic polyols, polycarbonate polyols, polyhydroxylalkanes, polyurethane polyols, castor oil or mixtures thereof (hereinafter referred to as organic polyol (1) There is.).

The polyester polyols include, for example, dibasic acids such as terephthalic acid, isophthalic acid, adipic acid, azelaic acid, sebacic acid, and dialkyl esters thereof, and mixtures thereof, for example, ethylene glycol, propylene glycol, diethylene glycol, butylene Glycol, neopentyl glycol,
Glycols such as 1,6-hexanediol, 3-methyl-1,5-pentanediol, 3,3'-dimethylolheptane, polyoxyethylene glycol, polyoxypropylene glycol, polytetramethylene ether glycol or a mixture thereof And polyester polyols obtained by ring-opening polymerization of lactones such as polycaprolactone, polyvalerolactone and poly (β-methyl-γ-valerolactone).

Examples of the polyether polyol include, as an initiator, an oxirane compound such as ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran, and a low-molecular-weight polyol such as water, ethylene glycol, propylene glycol, trimethylolpropane, and glycerin. And polyether polyols obtained by polymerization.

As the polyether ester polyol, for example, a dibasic acid such as terephthalic acid, isophthalic acid, adipic acid, azelaic acid, sebacic acid or a dialkyl ester thereof or a mixture thereof is reacted with the above polyether polyol. And the resulting polyetherester polyols.

As the polyesteramide polyol,
In the above esterification reaction, for example, it is obtained by using an aliphatic diamine having an amino group such as ethylenediamine, propylenediamine, hexamethylenediamine and the like as a raw material.

Examples of the acrylic polyol include hydroxyethyl acrylate, hydroxypropyl acrylate, acrylhydroxybutyl and the like having one or more hydroxyl groups in one molecule, or a corresponding methacrylic acid derivative and the like. It is obtained by copolymerizing an acid, methacrylic acid or an ester thereof.

Examples of the polycarbonate polyol include ethylene glycol, propylene glycol,
1,4-butanediol, 1,5-pentanediol,
1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 1,8-nonanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 1,4-cyclohexanediol, , 4-cyclohexanedimethanol,
One obtained by reacting one or more glycols selected from bisphenol A and hydrogenated bisphenol A with dimethyl carbonate, diphenyl carbonate, ethylene carbonate, phosgene, and the like.

The polyhydroxyalkane includes butadiene or a liquid rubber obtained by copolymerizing butadiene with acrylamide.

The polyurethane polyol is a polyol having a urethane bond in one molecule.
An organic polyisocyanate and a polyether polyol, polyester polyol, polyether ester polyol or the like having a number average molecular weight of 200 to 20,000 are mixed with NCO /
It is obtained by reacting when OH is less than 1, preferably 0.9 or less.

In the present invention, as the above-mentioned organic polyol,
A compound having a carboxyl group in the molecule (inside or inside the molecule) (hereinafter referred to as organic polyol (2)) can be used. The organic polyol (2) used in the present invention is desirably obtained by reacting the above-mentioned organic polyol (1) with a polybasic acid or an anhydride thereof. The organic polyol (1) used at this time contains two or more hydroxyl groups at the molecular terminals, and has a number average molecular weight of 1,000 to 100,000, preferably 3,0.
Those having a size of from 00 to 15,000 are preferably used. 1,
If it is less than 000, the cohesive force is insufficient, and 100,000
In the above, it is difficult to react a polybasic acid or its anhydride at the terminal from the viewpoint of synthesis, and there is a possibility that remarkable thickening or gelation may occur.

Examples of the polybasic acid or its anhydride include aromatic polybasic acids such as phthalic acid, trimellitic acid, and pyromellitic acid, and anhydrides thereof.
Those anhydrides such as phthalic anhydride, trimellitic anhydride, and pyromellitic anhydride are particularly preferred. Further, ethylene glycol bis-anhydrotrimellitate, glycerol tris-anhydrotrimellitate, ethylene glycol bis-anhydropyromellitate, glycerol tris-anhydropyromellitate derived from these anhydrides, and abietic acid as a rosin component Further, a C ₁₀ H ₁₆ diene compound, a derivative obtained by adding a maleic anhydride to a mixture thereof, or the like can be used.

In the synthesis of the organic polyol (2), after the synthesis of the organic polyol (1), a polybasic acid or its anhydride,
Preferably, the reaction is carried out by adding a polybasic acid anhydride under heating.In the case of synthesizing an organic polyol, a polycarboxylic acid and a polyhydric alcohol containing a carboxyl group in a molecule inside or at a molecular terminal in one step are used. It is possible to get.
The reaction with these polybasic acid anhydrides has a promoting effect in improving the adhesive performance of the adhesive composition according to the present invention, for example, hot water resistance, oil resistance, acid resistance and the like. The reaction between the organic polyol and the polybasic acid anhydride is controlled at a reaction temperature of 200 ° C. or lower, preferably in the range of 150 to 180 ° C., so that the esterification reaction by the ring opening reaction of the polybasic acid anhydride becomes the main reaction. There is a need to. The reaction ratio between the two is set so that the polybasic acid anhydride is consumed in an amount that consumes 40% or more of the hydroxyl groups in the molecule of the organic polyol. Here, “%” is based on the number of hydroxyl groups in the molecule of the organic polyol. When the above value is less than 40%, the resulting composition does not sufficiently improve the acid resistance.

Also, when an aliphatic polycarboxylic acid anhydride is used as the polybasic acid anhydride, a carboxyl group can be introduced into the molecule in the same manner. The use of group polycarboxylic anhydrides is not preferred. Furthermore, when a polyester polyol or a polyetherester polyol is used for the organic polyol (1),
When only aromatic polycarboxylic acids are used as the starting carboxylic acids, there are many problems in controlling the physical properties of the organic polyol (1). In particular, trivalent or tetravalent polycarboxylic acids give rise to branched organic polyols (1), which tend to gel and cannot be used in large quantities. In addition, since aromatic polycarboxylic acids have sublimability, during the synthesis of the organic polyol (1), these sublimates adhere to a reaction vessel or a dehydrating apparatus, which makes production difficult. In this regard, when an organic polyol having a carboxyl group in the molecule (organic polyol (2)) is used, the above-described problem can be avoided.

The oxyacid of phosphorus or a derivative thereof to be mixed with the organic polyol used in the present invention may be any as long as it has at least one free oxyacid. Examples include phosphoric acids such as acid, phosphorous 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 above-described phosphorus oxyacid with alcohols while leaving at least one free oxyacid. Examples of these alcohols include aliphatic alcohols such as methanol, ethanol, ethylene glycol, and glycerin, and aromatic alcohols such as phenol, xylenol, hydroquinone, catechol, and phloroglicinol. The oxyacid of phosphorus or a derivative thereof may be used alone or in combination of two or more.

Examples of the organic polyisocyanate used in the present invention include trimethylene diisocyanate,
Tetramethylene diisocyanate, hexamethylene diisocyanate, 1,2-propylene diisocyanate,
1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanatomethyl caproate, etc. Aliphatic diisocyanate, 1,4
-Cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanatomethyl-
3,5,5-trimethylcyclohexyl isocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), methyl 2,4-cyclohexane diisocyanate, methyl 2,6-cyclohexane diisocyanate, 1,4-bis (isocyanatomethyl) cyclohexane, Alicyclic diisocyanate such as 3-bis (isocyanatomethyl) cyclohexane, m-phenylene diisocyanate, p-phenylene diisocyanate,
4,4'-diphenyl diisocyanate, 1,5-naphthalenediisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4- or 2,6-tolylene diisocyanate or a mixture thereof, 4,4'-toluidine diisocyanate, dianisidine diisocyanate ,
Aromatic diisocyanates such as 4,4'-diphenyl ether diisocyanate, 1,3- or 1,4-xylylene diisocyanate or a mixture thereof, ω, ω'-diisocyanate-1,4-diethylbenzene, 1,3-
Or araliphatic diisocyanate such as 1,4-bis (1-isocyanate-1-methylethyl) benzene or a mixture thereof, triphenylmethane-4,4 ', 4 "-
Organic triisocyanates such as triisocyanate, 1,3,5-triisocyanatebenzene, 2,4,6-triisocyanate toluene, 4,4'-diphenyldimethylmethane-2,2'-5,5'-tetraisocyanate Polyisocyanate monomers such as organic tetraisocyanate, dimers, trimers, biurets, allophanates derived from the above polyisocyanate monomers,
Polyisocyanates having a 2,4,6-oxadiazinetrione ring obtained from carbon dioxide and the polyisocyanate monomer, for example, ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, neopentyl glycol, 6-hexanediol, 3-methyl-1,5-pentanediol, 3,
Adducts with low-molecular-weight polyols having a molecular weight of less than 200, such as 3'-dimethylolpropane, cyclohexanedimethanol, diethylene glycol, triethylene glycol, dipropylene glycol, glycerol, trimethylolpropane, pentaerythritol, and sorbitol;
Alternatively, adducts such as polyester polyols, polyetherester polyols, polyesteramide polyols, polycaprolactone polyols, polyvalerolactone polyols, acrylic polyols, polycarbonate polyols, polyhydroxyalkanes, castor oil, and polyurethane polyols having a molecular weight of 200 to 20,000 may be used. No.

As the silane coupling agent used in the present invention, any one represented by the following general formula (I) or (II) can be used.

[0027]

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In the formula, R represents an organic group having a vinyl group, an epoxy group, an amino group, an imino group or a mercapto group;
Represents a lower alkyl group, X represents a methoxy group, an ethoxy group or a chlorine atom. Examples of the silane coupling agent include chlorosilanes such as vinyltrichlorosilane, N-
Aminosilanes such as (dimethoxymethylsilylpropyl) ethylenediamine, N- (triethoxysilylpropyl) ethylenediamine, epoxysilanes such as γ-glycidoxypropyltrimethoxysilane and γ-glycidoxypropyltriethoxysilane, vinyltriethoxysilane and the like Vinyl silane and the like.

The epoxy resin used in the present invention includes, for example, diphenolmethane (bisphenol F), diphenolethane, diphenolpropane (bisphenol A), polyvinylphenol, polyisopropenylphenol, bisphenol A tetrabromide, , 1
-Bis- (4-hydroxyphenyl) -1-phenylethane, 1,1-bis- (4-hydroxyphenyl)-
Epoxy compounds derived from 1,1-dimethylmethane and the like; phenol novolak, brominated phenol novolak, cresol novolak, brominated cresol novolak, resorcinol novolak, brominated resorcinol novolak, and other novolak resins; resorcinol, hydroquinone, Polyphenolic epoxy resin derived from methylresorcinol, bisphenol A tetrachloride, etc .; derived from aniline, p-aminophenol, m-aminophenol, p-amino-m-cresol, 4,4'-diaminodiphenylmethane, etc. Amine epoxy resins; glycidyl ester compounds derived from aromatic carboxylic acids such as p-oxybenzoic acid, m-oxybenzoic acid, terephthalic acid, isophthalic acid; and 5,5′-dimethylhydantoin Guide is the hydantoin epoxy resin; 2,2'-bis (4- (3,4-epoxycyclohexyl) propane, 2,2'-bis (4- (2,3
Alicyclic epoxy resins such as epoxycyclohexyl) propane and vinylcyclohexene oxide; and others such as triglycidyl isocyanurate and 2,4,6-triglycidoxy-5-triazine.
A dimer acid-modified epoxy resin, a urethane-modified epoxy resin, or the like, a modified product thereof, or a hydrogenated bisphenol A-type epoxy resin, which is a hydrogenated product of a bisphenol A-type epoxy resin, can also be used. Among them, when used for laminating food packaging materials, hydrogenated bisphenol A type epoxy resin, dimer acid-modified epoxy resin and the like are preferable in consideration of safety. The epoxy resin is 2
More than one species may be used.

The above-mentioned epoxy resins are all commercially available, and can be appropriately selected from those commercially available products as needed. As a specific example of a commercially available product, for example, Yuka Shell Epoxy Co., Ltd., trade name: Epicoat 1002
(Bisphenol A type epoxy resin); manufactured by Toto Kasei Co., Ltd.
Trade name: ST-3000 (hydrogenated bisphenol A type epoxy resin); Asahi Denka Kogyo KK, trade name: EPU 6 (dimer acid modified epoxy resin) and the like. Of course, it is not limited to these. Further, for the purpose of lowering the viscosity of these epoxy resins, a small amount of a low-molecular-weight epoxy compound such as butyl glycidyl ether having an epoxy group in the molecule can be blended in a small amount, and the obtained adhesive can be used. Can be adjusted.

The adhesive composition of the present invention comprises a composition (I) in which the organic polyol (1) or the organic polyol (2) is mixed with the oxyacid of phosphorus or a derivative thereof, and an organic polyisocyanate and a silane coupling agent. The composition (II) obtained by mixing the above is blended. When the organic polyol (1) or the organic polyol (2) is mixed with the oxygen acid of phosphorus or a derivative thereof to form the composition (I),
When the organic polyisocyanate and the silane coupling agent are mixed into the composition (II), the two components may be simply mixed to form the composition (I) or the composition (II). It is desirable to mix each in the presence of a solvent. As the organic solvent, for example, an ester type such as ethyl acetate, a ketone type such as methyl ethyl kent, a toluene, an aromatic hydrocarbon type such as xylene and the like are used as long as they are inert to isocyanates. Is also good.

The oxygen acid of phosphorus or a derivative thereof, which is a component of the composition (I), is added to the adhesive composition in an amount of 0.01 to 0.01%.
It is used in an amount of 10% by weight, preferably 0.05 to 5% by weight, more preferably 0.1 to 1% by weight. If the amount used is less than 0.01% by weight, the acid resistance of the inner layer side of a metal foil such as an aluminum foil becomes insufficient, and
If the amount is more than 10% by weight, the water resistance on the inner layer side and the outer layer side of a metal foil such as an aluminum foil becomes insufficient. The amount of the silane coupling agent used as a component of the composition (II) is
The range is preferably from 0.1 to 5% by weight based on the adhesive composition. If the amount is less than 0.1% by weight, the adhesiveness to a metal foil such as an aluminum foil becomes insufficient, and the amount becomes 5% by weight.
If it exceeds 300, the cohesive force of the adhesive will decrease, and the heat resistance will decrease.

The organic polyol (1) and the organic polyisocyanate are blended so that the equivalent ratio of the isocyanate group of the organic polyisocyanate to the hydroxyl group of the organic polyol (1) is 1.0 to 5.0. . If the equivalent ratio is less than 1.0, curing will be poor, and sufficient resistance will not be obtained. If it exceeds 5.0, curing time, hygiene and economy will be disadvantageous. Further, the organic polyol (2) and the organic polyisocyanate are such that the isocyanate group of the organic polyisocyanate becomes 1.0 to 5.0 in equivalent ratio to the total of the hydroxyl group and the carboxyl group of the organic polyol (2). It is blended in. If the equivalent ratio is less than 1.0, curing will be poor, and sufficient resistance will not be obtained. If it exceeds 5.0, curing time, hygiene and economy will be disadvantageous.

Further, the adhesive composition of the present invention can further contain an epoxy resin in the composition (I) and / or the composition (II). The epoxy resin is blended in an amount of 1 to 50% by weight, preferably 1 to 30% by weight, based on the adhesive composition. If the amount of the epoxy resin is less than 1% by weight, no effect is exerted on the adhesiveness to a metal foil such as an aluminum foil, and if it exceeds 50% by weight, the flexibility is reduced and the adhesive strength is insufficient.

The adhesive composition of the present invention can be produced by blending the above composition (I) and composition (II), and further includes, for example, an antioxidant, an ultraviolet absorber, and a hydrolysis agent. Additives such as an inhibitor, a fungicide, a thickener, a plasticizer, a pigment, and a filler can be added as necessary. Known catalysts, additives and the like can be used to control the curing reaction.

When the adhesive composition of the present invention is used,
Its viscosity is from room temperature to 150 ° C., preferably from room temperature to 100 ° C.
100 to 10,000 mPa · s, preferably 100
In the case of ５，5,000 mPa · s, a solventless type can be used. When the viscosity of the composition is higher than the above range,
It may be diluted with an organic solvent. As the organic solvent, for example, any solvent may be used as long as it is inert to isocyanates such as an ester such as ethyl acetate, a ketone such as methyl ethyl kent, and an aromatic hydrocarbon such as toluene and xylene. May be used.

The method of using the adhesive composition of the present invention is as follows. The adhesive composition is applied to the film surface by a solvent type or solventless type laminator. In the case of the solvent type, the solvent is volatilized and then the solventless type. Then, the bonding surfaces are stuck together and cured at room temperature or under heating. Usually, it is convenient to use the coating amount in the range of 1.0 to 2.0 g / m ^{2 in} the non-solvent type and the dry solid amount in the range of 2.0 to 5.0 g / m ^{2 in} the solvent type.

The adhesive composition of the present invention has excellent adhesive performance as compared with conventional urethane-based adhesives, and particularly, plastic films such as polyester, polyamide, polyethylene, and polypropylene, aluminum, silicon oxide, and the like.
Plastic film on which aluminum oxide is deposited,
Shows excellent bonding strength, hot water resistance and acid resistance to metals such as stainless steel, iron, copper and lead.

[0039]

Next, the present invention will be described more specifically with reference to examples and comparative examples. All percentages in the examples and comparative examples mean% by weight. (Synthesis Example 1) 265.6 g of isophthalic acid, 44.6 g of ethylene glycol, and 74.9 of neopentyl glycol
g, 113.3 g of 1,6-hexanediol,
The esterification reaction was carried out at 200 to 220 ° C. for 6 hours. After distilling a predetermined amount of water, adipic acid (58.4 g) was added.
A time esterification reaction was performed. After distilling out a predetermined amount of water, 0.13 g of tetraisobutyl titanate was added, the pressure was gradually reduced, and a transesterification reaction was performed at 1.33 to 2.67 hPa and 230 to 250 ° C. for 3 hours to obtain an acid value of 1.3. A polyester polyol having a number average molecular weight of 9,000 was obtained. This polyester ester polyol is treated with ethyl acetate for a non-volatile content of 6.
The content was adjusted to 0% to obtain an organic polyol solution A.

(Synthesis Example 2) 265.6 g of isophthalic acid,
44.6 g of ethylene glycol, 74.9 g of neopentyl glycol, 113.3 g of 1,6-hexanediol
Was charged, and an esterification reaction was carried out at 200 to 220 ° C. for 6 hours. After distilling off a predetermined amount of water, 58.4 g of adipic acid was added, and the esterification reaction was carried out for another 6 hours. After distilling a predetermined amount of water, the pressure was gradually reduced to 1.33 to 2.67 hPa,
Excess ethylene glycol was removed from the system at 30 to 250 ° C. for 6 hours to obtain a polyester polyol. 17.8 g of isophorone diisocyanate was reacted at 150 ° C. for 2 hours with 400 g of the polyester polyol,
A polyester polyol having a number average molecular weight of 8,000 was obtained. This polyester polyol was adjusted to a nonvolatile content of 60% with ethyl acetate to obtain an organic polyol solution B.

(Synthesis Example 3) To the total amount of the polyester polyol obtained in Synthesis Example 1, 7.7 g of pyromellitic anhydride was added and reacted at 180 ° C. for about 2 hours. After confirming that no unreacted pyromellitic anhydride remained in the reaction system using liquid chromatography, the organic polyol solution C was obtained by adjusting the nonvolatile content to 60% with ethyl acetate. This organic polyol has about 90% of terminal hydroxyl groups reacted with pyromellitic anhydride.

(Examples 1 to 5) Organic polyol solution A,
B or C and an oxygen acid of phosphorus shown below, or an epoxy resin shown below are further mixed with these in a ratio (weight ratio) shown in Table 1 to obtain a composition (I), and an organic polyisocyanate shown below and The composition (II) was obtained by mixing a silane coupling agent or an epoxy resin shown below in the ratio shown in Table 1. Composition (I) and composition (II)
Was added and ethyl acetate was added so that the nonvolatile content became 30%, to obtain an adhesive composition. After each of these adhesive compositions was used to prepare a composite film by the following method, a peel strength test, a hot water resistance test, and an acid resistance test were performed on each of the obtained films as follows, and the results were tabulated. 2 is shown. Oxygen acid of phosphorus: 85% orthophosphoric acid Epoxy resin: Epicoat 1002 (manufactured by Yuka Shell Epoxy) Organic polyisocyanate: CAT-RT1 (trade name, manufactured by Toyo Morton Co., Ltd.) Silane coupling agent: γ-glycidoxypropyl tri Methoxysilane (Shin-Etsu Silicone Co., Ltd.)

(Preparation of 4-layer composite film) Polyethylene terephthalate film (thickness 12 μm) / printing / nylon film (thickness 15 μm) / aluminum foil (thickness 9 μm) / unstretched polypropylene (thickness 70 μm, surface corona treatment) Was produced by the method described below. That is, the adhesive composition was first applied to a polyethylene terephthalate film at room temperature by a laminator, and after the solvent-containing composition was evaporated, the applied surface was bonded to a nylon film. Further, an adhesive was similarly applied to the other surface of the nylon film of the composite film, and the one containing the solvent was volatilized, and the applied surface was bonded to the aluminum foil surface. Next, the unstretched polypropylene film was bonded to the other surface of the aluminum foil of the composite film, and kept at a temperature of 50 ° C. for a certain period of time to prepare a composite film.

(Peeling Strength Test) A test piece having a size of 300 mm × 15 mm was prepared from the composite film prepared as described above, and a tensile tester was used.
Peeling speed 3 by T-peeling under conditions of 65% relative humidity
0 cm / min, and (2) 180 ° C under the condition of a temperature of 135 ° C.
At a peeling rate of 30 cm / min, and a lamination strength (N) between the nylon film and the aluminum foil, respectively.
/ 15 mm). The numerical values in Table 2 are the average values of five test pieces.

(Hot Water Resistance Test) A pouch having a size of 21 cm × 30 cm was prepared using each composite film, and 1 kg of water was vacuum-filled as a content. This pouch is 30 r. p. m. 135 ° C, 30 minutes, 294kPa
After performing hot water sterilization under pressure, the peeling state between the nylon film and the aluminum foil was observed. In Table 2,
○ indicates no peeling, Δ indicates partial peeling, and × indicates complete peeling.

(Acid Resistance Test) A pouch having a size of 9 cm × 13 cm was prepared using each composite film, and vinegar having a concentration of 4.2% or more was filled as a content. Put this pouch in 3r. p. m. 135 ° C, 30 minutes,
After hot water sterilization under a pressure of 294 kPa, the laminate strength before and after the retort between the polypropylene film and the aluminum foil, and the laminate strength and the peeling state after storage at 60 ° C. for 14 days were examined. Laminate strength (N / 1
5 mm) is the average value for 5 bags each. Table 2
In the table, は indicates no peeling, Δ indicates partial peeling, and × indicates complete peeling.

(Comparative Examples 1 to 5) Organic polyol solution A,
B or C and an oxygen acid and a silane coupling agent of phosphorus shown below, or an epoxy resin shown below mixed with these at a ratio shown in Table 1 to obtain a composition, and then an organic polyisocyanate shown below, Alternatively, a composition obtained by mixing the following epoxy resins in the proportions shown in Table 1 was added, and ethyl acetate was added so that the nonvolatile content became 30% to obtain an adhesive composition. After each of these adhesive compositions was used to prepare a composite film in the same manner as in Examples 1 to 5, for each of the obtained films, Examples 1 to 5 were used.
A peel strength test, a hot water resistance test and an acid resistance test were carried out in the same manner as in Example 2 and the results are shown in Table 2.

[0048]

[Table 1]

[Table 2]

From Table 2, it can be seen that the composition of the present invention is excellent as an adhesive for a composite laminate film for producing a packaging material for a retort food.

[0050]

The composition of the present invention exhibits extremely excellent adhesive strength and hot water resistance between a metal foil such as aluminum and a plastic film such as polyester, nylon, polyethylene, polypropylene, etc. Even if retort sterilization treatment is performed at 120 ° C. or more in a state of filling, a packaging material having good long-term storage stability of a food can be obtained without separation between the metal foil and the plastic film.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Ryosuke Otomo 25-26, Namekawa-cho, Hiki-gun, Saitama Prefecture Toyo Morton Co., Ltd. Saitama Plant (72) Inventor Takashi Yamada 25-name, Namekawa-cho, Hiki-gun, Saitama Prefecture 26 Toyo Morton Co., Ltd. in Saitama Plant (72) Inventor Yoshihiro Sato 25-26 Miyako-cho, Hiki-gun, Saitama Prefecture Toyo Morton Co., Ltd. in Saitama Plant (72) Inventor Yuki Nakajima Namekigawa-cho, Hiki-gun, Saitama Prefecture 25-25, Tokyo, Saitama Plant, Toyo Morton Co., Ltd. (72) Inventor Masato Kaihara 25-26, Namekawa-cho, Hiki-gun, Higashi-gun, Saitama Prefecture F-term (reference) 4F100 AB10 AB33 AK07 AK42 AK48 AK51B AK51G AK53B AK53G AL05B AL05G AT00A AT00C BA03 BA06 BA10A BA10C CB02 EC18 GB15 JL11 4J040 EC041 EC042 EC061 EC062 EC071 EC072 EC081 EC082 EC121 EC122 EC131 EC132 EC161 EC162 EC321 EC322 EF081 EF082 EF111 EF112 EF121 EF122 EF131 EF132 EF161 EF162 EF181 EF182 EF251 EF252 EF281 EF282 GA27 HA286 HD24 HD30 HD35 HD36 KA23 MA02 MA10 MA11 MB03 NA08

Claims (5)

[Claims] 1. A composition (I) in which an organic polyol and an oxygen acid of phosphorus or a derivative thereof are mixed, and a composition (I) in which an organic polyisocyanate and a silane coupling agent are mixed.
A urethane-based adhesive composition containing I). 2. The urethane-based adhesive composition according to claim 1, wherein the composition (I) is further mixed with an epoxy resin. 3. The urethane-based adhesive composition according to claim 1, wherein the composition (II) is further mixed with an epoxy resin. 4. The urethane adhesive composition according to claim 1, wherein the organic polyol is an organic polyol containing a carboxyl group in a molecule. 5. A laminated film laminate formed by bonding with the urethane-based adhesive composition according to any one of claims 1 to 4.