JPS6354319B2 - - Google Patents

Description

[Detailed description of the invention]

Industrial Application Field The present invention is a two-component adhesive, more specifically, it is composed of a water-based main emulsion and a curing agent, and has particularly excellent initial adhesive strength after lamination and adhesive strength (creep resistance) when heated at high temperatures. The present invention relates to two-component adhesives. Conventional technology and problems to be solved In recent years, organic solvent-based adhesives have been avoided as adhesives for various purposes due to safety, health, and pollution concerns.
Chemical reaction curing type or emulsion type adhesives have come into use. In particular, emulsion-type adhesives have the advantage of being particularly safe and hygienic, as well as having a relatively low viscosity, making it easy to apply by spraying, etc., and can be applied with simple equipment.
It has the disadvantage that the initial adhesive strength is slow to develop and furthermore, the adhesive strength decreases at high temperatures. Therefore, the present inventors developed an aqueous emulsion of a polymer or copolymer whose essential monomer is an addition reaction product of an acrylic ester or methacrylic ester having a tertiary amino group and epihalohydrin, and added a curing agent to this emulsion. It consists of a combination of polyethyleneimine and polyethyleneimine. We have created a two-component adhesive that has a fast crosslinking rate and excellent adhesive strength when heated, and a patent application for this is already pending (Japanese Patent Application Laid-Open No. 1983-1999).
(Refer to Publication No. 52376). However, such two-component adhesives were subsequently subjected to practical tests, and flexible material sheets (for example, synthetic resin foam laminated with a skin layer) were attached to synthetic resin molded plates of various shapes using a vacuum forming machine or press. When automobile interior materials are produced by pressure bonding with a molding machine, for example, in the adhesion process of doors, inside trims such as pillars, instrument panels, molded ceilings, console boxes, etc., the adhesive is used to improve workability and productivity. This is done by preheating the adherend on the side to which the agent has not been applied, or by heating it further after lamination to cure and harden it. Since the material is laminated, there is no problem if the adhesive strength is greater than the tension of the flexible material sheet, but if the adhesive strength is low, it may rise and bulge, especially in complex shapes. Difficult to put into practical use. In view of these circumstances, the present inventors have carried out intensive research on improving the initial adhesive strength and hot adhesive strength of emulsion type adhesives, and found that a specific tackifier resin emulsion and The present inventors have discovered that the desired adhesive effect can be obtained and the types of curing agents can be expanded by blending together with an epoxy resin emulsion, and the present invention has been completed. That is, the present invention provides (i) an aqueous emulsion of a polymer or copolymer whose essential monomer is an addition reaction product of an acrylic ester or methacrylic ester having a tertiary amino group and epihalohydrin;
a base emulsion consisting of a tackifying resin emulsion and an epoxy resin emulsion selected from the group of petroleum hydrocarbon resins, phenolic resins, terpene resins, rosin derivatives, coumaron resins and coumaron indene resins; (ii) a first hardening agent; The present invention provides a two-component adhesive comprising a compound having primary and secondary amino groups, which can particularly advantageously be used to bond synthetic resin molded plates and flexible material sheets. In the components of the base emulsion in the present invention, the addition reaction product of an acrylic ester or methacrylic ester having a tertiary amino group, which is an essential monomer, and epihalohydrin has the formula or expression [In the formula, R is hydrogen or methyl; A has 2 carbon atoms
~6 alkylene or (CH ₂ CH ₂ O) _o CH ₂ CH ₂
- (where n is an integer of 1 or more); X is iodine, bromine or chlorine; Y is a monovalent anion] is used. The monomer is produced by a known method, for example, the method described in Japanese Patent Publication No. 47-21087. The polymer or copolymer used in the present invention can be obtained by polymerizing or copolymerizing one or more of the monomers or one or more of the monomers and the following monomer having an ethylenic double bond by a conventional method. A polymer is obtained. Examples of monomers having an ethylenic double bond include C1 _{to C18} fatty acid vinyl esters such as vinyl acetate, vinyl laurate, and vinyl stearate; _C1 to _C18 alkanols, benzyl alcohol, cyclohexyl alcohol, Acrylic or methacrylic esters of C ₁ to C ₁₈ alcohols, including isobornyl alcohol (e.g. methyl acrylate or methacrylate, ethyl acrylate or ethyl methacrylate, butyl acrylate or methacrylate) butyl, 2-ethylhexyl acrylate or methacrylate, octadecyl acrylate or methacrylate); vinyl aromatic hydrocarbons (e.g. styrene, isopropenyltoluene, and various dialkylstyrenes); acrylonitrile, methacrylonitrile, Ethacrylonitrile and phenyl acrylonitrile; acrylamide, methacrylamide, ethacrylamide, N-methylolacrylamide, N-monoalkylacrylamides, N-dialkylacrylamides and methacrylamides, i.e. N-monomethyl, -
Ethyl, -propyl, -butyl, and N-dimethyl, -diethyl, -dipropyl, -dibutylacrylamide or methacrylamide, etc.; alacrylamides, i.e., N-monophenyl,
and N-diphenylacrylamide and -methacrylamide; vinyl ethers such as butyl vinyl ether; N-vinyl lactams such as N-vinylpyrrolidone; olefins such as ethylene; fluorinated vinyl compounds such as vinylidene fluoride; U.S. Patent No. 3150112 Specification No. 2-3
Hydroxyl group-containing or amine group-containing monomers or β-hydroxyethyl acrylate or methacrylate disclosed in the column; vinyl chloride and vinylidene chloride; alkyl vinyl ketones, namely methyl vinyl ketone, ethyl vinyl ketone, and methyl isopropenyl ketone ;1 piece
itaconic acid diesters containing a CH ₂ =C group;
i.e. dimethyl, diethyl, dipropyl, dibutyl and other saturated aliphatic monohydric alcohol diesters of itaconate, diphenyl itaconate,
Dibenzyl itaconate, di(phenylethyl) itaconate; allyl and methallyl esters of saturated aliphatic monocarboxylic acids, i.e. allyl acetate;
Included are methallyl acetate, allyl propionate, methallyl propionate, allyl valerate and methallyl valerate; vinylthiophene; 4-vinylpyridine; and vinylpyrrole. Such polymers or copolymers are used in the form of aqueous emulsions, which can be prepared by pre-polymerizing and emulsifying and dispersing them in water, or directly by emulsion polymerization. May be manufactured. In the emulsion,
It is preferable to use one containing a resin content of 40 to 60% (weight %, hereinafter the same). As the tackifier resin emulsion which is a component of the main emulsion in the present invention, one or more emulsions selected from the following groups (-) are used. Petroleum-based hydrocarbon resins: For example, synthetic polyterpene resins (product name "Quinton" manufactured by Nippon Zeon Co., Ltd.), aliphatic hydrocarbon resins, aliphatic cyclic hydrocarbon resins, aromatic hydrocarbon resins, olefinic unsaturated hydrocarbons resins, isoprene resins (trade names "Petrozine" and "Hiretsu" manufactured by Mitsui Petrochemicals, "Escolets" manufactured by Etsuo Oil Co., Ltd.), etc. Phenol resins, such as pt-butylphenol/acetylene resin, phenol/formaldehyde resin (trade name "Tamanol" manufactured by Arakawa Hayashi Chemical Industry Co., Ltd.), terpene/phenol resin (trade name "YS Polyster" manufactured by Yasuyu Kogyo Co., Ltd.)
etc. Terpene resin. Rosin derivatives, such as pentaerythritol ester of rosin, glycerol ester of rosin, etc.
Ester (product name "Harier Star" manufactured by Harima Kasei Co., Ltd.), hydrogenated rosin, etc. Coumaron resin. Coumaron-indene resin. Among these, petroleum-based hydrocarbon resins and rosin derivatives are particularly preferred. Such tackifying resins are available in the form of aqueous emulsions. To make an emulsion, first, the resin is diluted and dissolved in a water-insoluble organic solvent (for example, toluene, xylene, benzene, cyclohexane, carbon tetrachloride, etc.) to a relatively high concentration (preferably 50% or more) to obtain a resin solution. . On the other hand, suitable emulsifiers, such as salts of primary to tertiary alkylamines (laurylamine hydrochloride, dilaurylamine hydrochloride, lauryldimethylamine hydrochloride, etc.), alkanolamine salts (ethanolamine hydrochloride, etc.), polyethylene polyamines, etc. salts (ethylenediamine hydrochloride, diethylenetriamine hydrochloride, etc.), quaternary ammonium salts (alkyltrimethylammonium hydrochloride, etc.), cationic surfactants (morpholine, guanidine, hydrazine,
N,N-diethylethylenediamine, aminoethylethanolamine salts, etc.), carboxylate type nonionic surfactants (methyl lauryl aminopropionate hydrochloride, lauryl dimethyl betaine, etc.), nonionic surfactants (sulfate ester salt type) , sulfonate type, phosphate ester salt type, etc.)
An aqueous solution (usually 0.1 to 5% concentration) prepared by dissolving one or more of the following and, if necessary, a protective colloid (partially saponified polyvinyl alcohol, casein, glue, etc.) in water, is added to the above resin solution under high speed stirring. Phase inversion emulsification may be carried out by a solution emulsification method in which the solution is gradually dropped, and then, if necessary, the organic solvent in the system may be removed.
Further, as another method for emulsifying the tackifier resin, a hot melt emulsification method may be adopted in which the tackifier resin is heated to melt it above its melting point, and the above emulsifier aqueous solution heated to 80° C. or above is emulsified while being dropped therein. Usually solids content 30
Available for use in ~50% aqueous emulsion. The amount of this tackifying resin emulsion to be blended is 5 to 200 parts, preferably 10 to 100 parts, based on 100 parts (parts by weight, the same applies hereinafter) of the above component emulsion, in terms of solid content.
The selection can be made within the scope of the department. If it is less than 5 copies,
It is difficult to develop the desired adhesive strength, and if the amount exceeds 200 parts, the adhesive strength decreases and it becomes difficult to develop the initial adhesive strength. The epoxy resin emulsion, which is a component of the main emulsion in the present invention, includes (1) polyglycidyl ethers of polyhydric phenols or alkylene oxide adducts of polyhydric phenols (e.g., bisphenol A type diglycidyl ether, bisphenol A type ethylene oxide, (2) polyglycidyl ether of a polyhydric phenol or a hydrogenated product of an alkylene oxide adduct of the polyhydric phenol (for example, hydrogenated bisphenol type A polyglycidyl ether); (3) Polyglycidyl ether of aliphatic polyalcohol (e.g. glycerin triglycidyl ether, 1,6-hexanediol diglycidyl ether, diglycidyl ether of castor oil), formula (4): Diglycidyl ether of silicon-containing compounds such as compounds of formula (5): or An amine or amide polyglycidyl compound such as a compound of formula (6), an epoxy resin-modified polybutadiene resin described below, and (7) formula: diglycidyl esters of dicarboxylic acids, such as compounds of succinic acid diglycidyl ester (n
=2), adipic acid diglycidyl ester (n=
4) Emulsions of phthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, and tetrahydrophthalic acid diglycidyl ester can be mentioned, and one or more types selected from these groups can be used. Particularly preferred epoxy resin emulsions are emulsions of hydrogenated bisphenol A type diglycidyl ether, aliphatic polyalcohol diglycidyl ether, and epoxy resin-modified polybutadiene resin. Note that this component can also be made into an aqueous emulsion form by the same emulsion treatment as the above component. The above epoxy resin modified polybutadiene resin is 2
It is obtained by reacting a polybutadiene homopolymer and/or copolymer (hereinafter referred to as a polybutadiene polymer) having at least one terminal epoxy group and a carboxyl group at the terminal with an epoxy resin. Such a reaction is usually carried out by blending both of them in such a way that 2.0 to 20 equivalents of epoxy groups are used per equivalent of carboxyl group, and using a reaction catalyst (for example, 2-ethylimidazole, tetraethylammonium bromide, benzyldimethylamine, triethylenediamine, diethylamine, and butylamine). (0.01 to 5 mol % added to the epoxy group) at a temperature of 130 to 190°C.
Stir and mix for an hour. A specific example of the polybutadiene eplymer mentioned above is NissoPB-G-
1000”, “PB-G-2000”, “PB-G-3000”,
Examples include polybutadiene homopolymer or copolymer having no terminal carboxyl group to which maleic anhydride is added, such as "Poly-BD" manufactured by Arco. In addition, as the above-mentioned epoxy resin, ordinary ones may be used, for example, bisphenol A type epoxy resin (trade name manufactured by Ciel Chemical Co., Ltd., "Epicoat #827", "Epicoat #828", "Epicoat #834", "Epicoat #827", "Epicoat #828", "Epicoat #834", #836”, “Same #1001”, “Same #1004”,
“Araldite #1007”, “Araldite CY252”, “Araldite CY250”, “Araldite GY260”, “Araldite CY252” manufactured by Ciba Geigy
GY280, GY6071, GY6084, etc.), as well as novolac type epoxy resin, bisphenol A
Side chain type diglycidyl ether resin (product name: ADEKA RIN EP4000, manufactured by Asahi Denka Kogyo Co., Ltd.), urethane-modified epoxy resin, alicyclic epoxy resin, resorcin diglycidyl ether epoxy resin, glycidyl ester type epoxy resin, P-oxybenzoic acid Examples include diglycidyl ether epoxy resin, hydrogenated bisphenol A type epoxy resin, and glycidylamine epoxy resin. A specific example of such an epoxy resin-modified polybutadiene resin is one obtained by reacting 1,2-polybutadiene and bisphenol A diglycidyl ether type epoxy resin, and has the general formula: or Examples include those shown in . The amount of this epoxy resin emulsion (component) is calculated based on the solid content, and the amount of the above component emulsion is
The amount may be selected within the range of 0.5 to 100 parts, preferably 1 to 50 parts per 100 parts. If it is less than 0.5 parts,
It is difficult to obtain initial adhesive strength, and if it exceeds 100 parts, cohesive strength decreases and heat resistance tends to be difficult to develop. The base emulsion in the present invention includes the above-mentioned ~
It is prepared by blending the ingredients in predetermined proportions and further blending various usual ingredients as necessary.
Examples of the above-mentioned usual ingredients include nonionic thickeners (e.g., starch, guar gum, locust bean gum, gelatin, polyacrylamide, polyethylene oxide, hydroxyethyl cellulose, hydroxypropyl cellulose, etc.);
Cationic thickeners (e.g., water-soluble aniline resin hydrochloride, polydiallyldimethylammonium chloride, chitosan, etc.), fillers (e.g., calcium carbonate, silicic acid, silicates, clay, talc,
asbestos, etc.), plasticizers (e.g., higher alcohols, glycols, phthalate esters, etc.), colorants such as titanium white and other dyes and pigments, organic solvents, preservatives, antioxidants, rust preventives, viscosity stabilizers. , antifoaming agents, flavoring agents, etc. can be added. In the present invention, examples of the curing agent include compounds having primary and secondary amino groups, such as polyethyleneimine and its adducts, polyamide polyamide, imidazole, and amino resins, and particularly preferred are polyethylene imine and polyamide polyamine. used. In particular, those having a molecular weight in the range of 250 to 10,000 are preferred from the viewpoint of reactivity, workability, viscosity, etc. Usually, curing agents are used in an aqueous solution of 0.1% or more,
It may be used as is without dilution. In addition, other known curing agents such as polysulfide resins, phenols, condensates of phenols such as alkylphenols, and formalin may also be used in combination as appropriate.
Furthermore, if necessary, metal hydroxides and sodium sesquicarbonate may be added as catalysts in addition to the above-mentioned thickeners, colorants, and organic solvents. When the two-component adhesive according to the present invention is used, one of the base emulsion and the hardening agent, a primary emulsion, is used.
Although it is prepared by mixing a compound having a secondary amino group or an aqueous solution thereof, it may also be mixed at the same time as application by using a two-headed gun and simultaneously spraying onto the surfaces to be joined. From the viewpoint of workability, the first grade,
It is preferable to mix and use the compound having a secondary amino group in a proportion of 50 to 0.1 part, preferably 20 to 0.02 part. The two-component adhesive of the present invention having the above structure is mainly suitable for manufacturing automobile interior materials, for example, inside trims such as doors and pillars, instrument panels, molded ceilings, console boxes, etc. That is, the above-mentioned automobile interior material is formed by press molding or injection molding, using a complex-shaped core material and a skin material made of a flexible material sheet, using a water-based adhesive of the present invention, and then molding the material using a vacuum forming machine or a press. Produced by crimping with a molding machine. The above-mentioned molded plate is made of synthetic resin, for example
Manufactured from ABS, polypropylene, polyethylene, resin-impregnated hardboard, etc. On the other hand, the flexible material sheet may be a synthetic resin foam material such as polyethylene, polypropylene, polyurethane, or soft vinyl chloride, and/or a synthetic leather or sheet laminated thereon as a skin layer such as polyvinyl chloride, polyurethane, or the like; Examples include nonwoven fabrics made of various natural or synthetic fibers, resin-impregnated felts, and the like. When adhering a flexible material sheet to a molded plate using the adhesive of the present invention, the adhesive of the present invention is first applied onto the molded plate and dried by heating, but the adhesive layer is too hardened. 140℃ to maintain activity
Hereinafter, it is preferable to dry at 100°C or lower. On the other hand, the surface of the flexible material sheet is preferably heated in advance before being bonded to the adhesive layer of the molded plate. After joining, the flexible material sheet and the molded plate are pressed together using a vacuum forming machine or a press, and from the viewpoint of workability, a suitable time is 10 to 180 seconds. Thereafter, it is necessary to perform a post-crosslinking treatment, but the temperature is preferably 90° C. or higher, and a heating time of several minutes is sufficient. Hereinafter, the present invention will be explained in more detail based on Examples. Production Examples 1 to 17 (Preparation of aqueous emulsion of components) The tackifier resin (petroleum-based hydrocarbon resin, rosin derivative) and epoxy resin (polyglycol-based epoxy resin, hydrogenated bisphenol A type polyglycidyl ether, hydrogenated bisphenol A-type polyglycidyl ether, Epoxy resin-modified polybutadiene resin) is dissolved in toluene to a concentration of 50% by weight. Separately, an aqueous emulsion is prepared by emulsifying the resin toluene solution by an inversion method in which an aqueous emulsifier solution shown in Table 1 under high speed stirring is gradually added dropwise over 30 minutes using a homomixer. Table 1 shows the component concentration (number of parts) and viscosity of the emulsion. Furthermore, Production Example 17 is an example for comparison.

【table】

[Table] Production Examples 18 to 23 (Preparation of hardening agent aqueous solution) Polyethyleneimine,
A hardening agent aqueous solution is prepared by dissolving polyamide resin, polyamide polyamine or imidazole in water with stirring.

【table】

[Table] Examples 1 to 21 The above production example 1 for 100 parts of tertiary amino group-containing acrylic acid ester polymer emulsion (trade name "Primal E-1126" manufactured by Rohm & Half Co., Ltd., solid content 60%) A two-component adhesive according to the present invention is prepared by mixing 50 parts of the aqueous emulsion prepared in Steps 1 to 16 and 10 parts of the curing agent aqueous solution prepared in Production Examples 18 to 23 as shown in Table 3. Apply the mixed adhesive to an ABS resin plate (100 x 200 x 2 mm)
Spray 2.4g on one side of the
Let dry in minutes. On the other hand, polyethylene foam (product name: Torepef; manufactured by Toray Industries, 250 x 200 x 4 mm)
The adhesive surface of the adhesive was heat-treated at 140°C for 5 minutes, and this was pasted onto the adhesive-coated surface of the ABS resin, and pressed for 10 seconds using a press at a load of 200 g/cm ² . At this stage, the polyethylene foam was set horizontally in an atmosphere of 80°C with the polyethylene foam facing downward, and a weight of 200 g was suspended from one end of the polyethylene foam for 1 hour, but no sagging occurred. Also, when we measured the adhesive strength, it was 3.5
The polyethylene foam exhibited material failure with a strength of Kg/in. The results are shown in Table 3. Comparative Example 1 The same procedure as in Example is carried out except that 50 parts of the aqueous emulsion prepared in Production Example 17 and 10 parts of the hardening agent aqueous solution prepared in Production Example 19 are used. However, in a drop test in an 80°C atmosphere, it fell after 30 minutes. Also, when measuring the adhesive strength, it was 1.5
It showed a strength of Kg/in, and showed interfacial failure from the polyethylene foam side. The results are shown in Table 3.

【table】

[Table] As is clear from comparing the test results of Examples 1 to 21 and Comparative Examples above, the adhesive of the present invention has significantly greater initial adhesive strength and heat resistance than conventional emulsion-based two-component adhesives. I understand. It will also be understood that the adhesive of the present invention is suitable for pressure bonding of sheet materials such as flexible plastic foam.

Claims (1)

[Scope of Claims] 1 (i) Base emulsion consisting of the following components: A polymer or copolymer whose essential monomer is an addition reaction product of an acrylic ester or methacrylic ester having a tertiary amino group and epihalohydrin. Aqueous emulsion Petroleum-based hydrocarbon resin, phenolic resin,
Tackifying resin emulsion selected from the group of terpene resins, rosin derivatives, coumaron resins and coumaron indene resins.Epoxy resin emulsion (ii) characterized by comprising a compound having primary and secondary amino groups as a curing agent. Two-component adhesive. 2 In the base emulsion, the solid proportions of the components are 5 to 200 parts by weight and 100 parts by weight of the components.
Said first selected to be 0.5 to 100 parts by weight
Two-component adhesive described in Section 1. 3. The two-component adhesive according to item 1, wherein the solid distribution ratio of the base emulsion and the curing agent is selected such that the curing agent is 0.02 to 20 parts by weight per 100 parts by weight of the base resin. 4. The two-component adhesive according to item 1, wherein the tackifying resin emulsion is an emulsion of one or more selected from petroleum-based hydrocarbon resins and rosin derivatives. 5. The epoxy resin emulsion is one or two selected from hydrogenated diglycidyl ether of alkylene oxide adduct of polyhydric phenol and polyglycidyl ether of aliphatic polyalcohol.
The two-component adhesive according to item 1 above, which is an emulsion of more than one species.