JPH0827449A - Heat-resistant heat-sensitive adhesive and multilayer laminate using the same adhesive - Google Patents

Abstract

PURPOSE:To obtain a heat-resistant heat-sensitive adhesive containing a specific copolymer, a specific polyhydric alcohol compound and a specific reaction promotor in a specific ratio, excellent in thermal creep-resistance characteristics and aesthetic property and suitable for multilayer laminates, etc., for interior materials. CONSTITUTION:This heat-resistant heat-sensitive adhesive comprises (A) an ethylenic copolymer composed of 0.1-5wt.% of ethylene and a radically polymerizable acid anhydride and 10-50wt.% of a radically polymerizable comonomer other than these compounds, (B) a polyhydric alcohol compound such as a polyoxyalkylene compound having a structure obtained by adding ethylene oxide, etc., to a polyhydric alcohol compound of formula I [R<1> is H, a 1-12C alkyl, etc.; (a) is 0-2; (b) is 2-4; (a+b) is 4] or formula II [(m) is 0-10] and (C) a reaction accelerator such as an organic carboxylic acid metal salt. The molar ratio of a unit of hydroxyl group in the component B to an unit derived from a radically polymerizable acid anhydride in the component A is 0.01-10 and the amount of the component C is 0.001-20 pts.wt. based on 100 pts.wt. of the component A.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a heat-resistant heat-sensitive adhesive and a multilayer laminate using the adhesive. Specifically, automobiles and vehicles that have strong adhesiveness to a wide variety of base materials that are used daily and have excellent heat resistance, and in particular, require both low-temperature heat adhesiveness and high-temperature heat-resistant creep resistance at the same time. The present invention relates to a heat-sensitive adhesive composed of a specific resin composition, which is suitable as an adhesive used for an adhesive layer of a multilayer laminate for interior materials of ships, houses, etc., and a multilayer laminate using the adhesive. .

[0002]

2. Description of the Related Art Conventionally, hot-melt type adhesives have been used in the adhesive layers of various multilayer laminates. Unlike solvent-based adhesives, hot-melt adhesives do not require painting, drying, aging, and other work when bonding, and the work process is simple, and the adverse effects on occupational health and fire caused by the use of organic solvents It is widely used because it does not cause problems such as danger.

On the other hand, hot-melt type adhesives generally have insufficient adhesive strength as compared with solvent-type adhesives, and in particular, they often have poor heat creep resistance, and the problem that the adhesiveness is insufficient depending on the application is pointed out. It had been. For example, as an interior material for automobiles, vehicles, ships, houses, other buildings, and the like, a skin material for enhancing the habitability and aesthetics of the room,
A multi-layer laminate in which substrate materials are laminated to retain and enhance functionality is used, and an ethylene-acrylic acid ester-maleic anhydride terpolymer conventionally used as an adhesive layer of this multi-layer laminate. Hot-melt type adhesives such as ethylene-vinyl acetate copolymer, ethylene-acrylic acid ester copolymer or low-melting point copolymer nylon are exposed to a high temperature (around 80 ° C) such as the temperature in a car under hot weather for a long time. When it is peeled, it has a drawback that it easily causes sagging or peeling. In addition, the bonding strength can be increased by setting the heating temperature to a relatively high temperature of 120 ° C. or more during bonding, but in this case, there is a drawback that the skin material is likely to be damaged.

Further, the hot melt type adhesive has a problem that sufficient adhesiveness cannot be obtained depending on the kind of the base material (including the skin material and the substrate material). For example, when the surface of the base material is coated with urethane coating, when the base material is a foamed urethane type, or when the base material is injection-molded polypropylene and the surface is smooth, etc., sufficient adhesive strength is obtained. It is not obtained, and peeling of the base material layer is likely to occur. In such a case, it is necessary to perform a special treatment such as applying an anchor coating agent on the surface of the base material in advance, or to use a solvent type adhesive instead of the hot melt type adhesive. However, the former has a drawback that the work process is complicated and the manufacturing cost is increased, and the latter has environmental and hygiene problems due to the use of the organic solvent.

Further, as a conventional method for laminating and bonding a multi-layer laminate, other than a method using a hot press or a hot roll,
A method using vacuum pressure bonding is also used. With the method using a hot press or a heat roll, it is possible to use a conventional heat-sensitive adhesive because a sufficient pressure can be obtained, but the vacuum pressure bonding method can obtain only a pressure of 760 mmHg / cm ² at maximum. In addition, conventional ethylene-vinyl acetate copolymer, partial saponification product of ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid ester copolymer and copolymer nylon etc. Only a solvent-based adhesive was used.

[0006]

The problem to be solved by the present invention is that it can be used as an adhesive layer of a laminate for a wide variety of applications, and in particular, when it is used as an adhesive layer of an interior material for automobiles, etc. An object of the present invention is to provide an adhesive that simultaneously satisfies good low-temperature adhesiveness and heat-resistant creep resistance with respect to a substrate material.

[0007]

Means for Solving the Problems As a result of intensive studies to achieve the above-mentioned objects, the present inventors have found that a specific ethylene-based multi-component copolymer and a polyhydric compound having at least two hydroxyl groups in the molecule. It has been found that an adhesive resin composition comprising an alcohol compound and a reaction accelerator has high adhesive strength and heat-resistant creep resistance to a wide range of substrates. The present invention has been completed based on such findings.

That is, the present invention is (1) a multi-component copolymer comprising ethylene, a radical-polymerizable acid anhydride and a radical-polymerizable comonomer other than ethylene, which is derived from the radical-polymerizable acid anhydride in the copolymer. An ethylene copolymer in which the proportion of units is 0.1% by weight or more and 5% by weight or less, and the proportion of units derived from other radically polymerizable comonomers is 10 to 50% by weight, (2) a hydroxyl group in the molecule. A hydroxyl group in the polyhydric alcohol compound which is the component (2) with respect to the unit derived from the radical-polymerizable acid anhydride in the component (1), which comprises at least two polyhydric alcohol compounds and (3) a reaction accelerator. The molar ratio of the units is 0.01 to 10 and the reaction accelerator which is the component (3) is 0.00 relative to 100 parts by weight of the ethylene copolymer which is the component (1).
The present invention provides a heat-resistant heat-sensitive adhesive in the range of 1 to 20 parts by weight and a multilayer laminate using the adhesive.

The ethylene-based copolymer which is the component (1) of the present invention is a multi-component copolymer comprising ethylene, a radical-polymerizable acid anhydride and a radical-polymerizable comonomer other than the radical-polymerizable acid anhydride. . Here, the radical-polymerizable acid anhydride is a compound having at least one radical-polymerizable unsaturated bond and at least one acid anhydride group in the molecule, and capable of introducing an acid anhydride group into the molecule by polymerization. Means The acid anhydride group is preferably cyclic. Examples of such a compound include maleic anhydride, itaconic anhydride, citraconic anhydride, endic acid anhydride, dodecenyl succinic anhydride, 1-butene-3,4-dicarboxylic acid anhydride, and at most 18 carbon atoms. And alkadienyl succinic anhydride having a double bond at the terminal. These may be used alone or in combination of two or more kinds. Among these, maleic anhydride,
Itaconic anhydride is particularly preferred.

The ratio of the units derived from the radical-polymerizable acid anhydride in the ethylene copolymer as the component (1) is 0.
It is necessary to be in the range of 1 to 5% by weight, preferably 0.5 to 4.5% by weight, and particularly preferably 1.0 to 3.5% by weight. If the proportion of the radical-polymerizable acid anhydride is less than 0.1% by weight, the adhesive performance is insufficient and good adhesive strength cannot be obtained, and sufficient crosslink density cannot be obtained, resulting in sufficient heat creep resistance. I can't get it. On the other hand, if it exceeds 5% by weight, there is almost no effect of improving the adhesive strength, and further, it becomes difficult to manufacture it commercially, which is not preferable.

There are various compounds as the radical-polymerizable comonomer other than the radical-polymerizable acid anhydride constituting the ethylene-based copolymer as the component (1), such as an ethylenically unsaturated ester compound and an ethylene-based copolymer. Unsaturated amide compounds, ethylenically unsaturated acid compounds, ethylenically unsaturated ether compounds, ethylenically unsaturated hydrocarbon compounds,
Other compounds may be mentioned. When these are specifically described, examples of the ethylenically unsaturated ester compound include vinyl acetate, methyl (meth) acrylate, (meth)
Ethyl acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate,
Octyl (meth) acrylate, lauryl (meth) acrylate, benzyl (meth) acrylate, methyl fumarate,
Ethyl fumarate, propyl fumarate, butyl fumarate,
Dimethyl fumarate, diethyl fumarate, dimethyl fumarate, diethyl fumarate, dipropyl fumarate, dibutyl fumarate, methyl maleate, ethyl maleate, propyl maleate, butyl maleate, dimethyl maleate, diethyl maleate, maleic acid Examples thereof include dipropyl and dibutyl maleate. Examples of the ethylenically unsaturated amide compound include (meth) acrylamide,
N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-propyl (meth) acrylamide, N-butyl (meth) acrylamide, N-hexyl (meth) acrylamide, N-octyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, etc. are mentioned. Examples of the ethylenically unsaturated acid compound include (meth) acrylic acid, maleic acid, fumaric acid and the like. Examples of the ethylenically unsaturated ether compound include methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octadecyl vinyl ether, phenyl vinyl ether and the like. As the ethylenically unsaturated hydrocarbon compound,
Examples thereof include styrene, α-methylstyrene, norbornene, butadiene and the like. As other compounds, for example, (meth) acrylonitrile, acrolein, crotonaldehyde, trimethoxyvinylsilane,
Vinyl chloride, vinylidene chloride, N-vinyl acetamide and the like can be mentioned. Among these, methyl (meth) acrylate, ethyl (meth) acrylate and butyl (meth) acrylate are mentioned as particularly preferable compounds. These monomers may be used alone or in combination of two or more.

The ratio of the units derived from the radically polymerizable comonomer in the ethylene copolymer which is the component (1) is 1
The amount is in the range of 0 to 50% by weight, preferably 10 to 40% by weight, more preferably 12 to 35% by weight. Here, the ratio of the radically polymerizable comonomer is 10
If it is less than wt%, the crystal melting point of the ethylene-based copolymer will not be sufficiently lowered, and the low temperature adhesiveness will not be sufficiently exhibited. On the other hand, if it exceeds 50% by weight, it becomes difficult to handle the resin and the heat resistance of the product deteriorates. Although various methods such as radical polymerization and solution polymerization can be used as a method for producing the above-mentioned component (1), an ethylene-based copolymer, generally, a high-pressure process low-density polyethylene production facility is generally used. And manufactured using that technology. The ethylene copolymer as the component (1) melts at a relatively low temperature and is rich in physicochemical interactions with various base materials and reactivity, so that the resin composition of the present invention has a low temperature. It also plays a major role in exerting high adhesive strength during molding.

The polyhydric alcohol compound having at least two hydroxyl groups in the molecule of the component (2) relating to the present invention means a compound having two or more hydroxyl groups, which has a function as a so-called cross-linking agent. is there. Examples of such polyhydric alcohol compounds include ethylene glycol, glycerin, 1,4 butanediol, 1,6 hexanediol, 1,8 octanediol, 1,10 decanediol, trimethylolmethane, trimethylolethane, and triethylamine. Alcohol compounds such as methylolpropane and pentaerythritol; polyethylene glycols such as diethylene glycol, triethylene glycol and tetraethylene glycol; polyglycerins such as diglycerin, triglycerin and tetraglycerin; arbitol, sorbitol, xylose, arabinose, glucose, galactose, sorbose. , Fructose, palatinose, maltotriose, malezitose, sorbitan, and other sugars; dehydration condensation products of these sugars; Polyoxyalkylene compound of ethylene oxide or is obtained by adding propylene oxide; compounds of the above-mentioned various compounds partially esterified with carboxylic acids;
A compound obtained by partially esterifying the above polyoxyalkenylene compound with a carboxylic acid; a polyoxyalkylene compound obtained by further adding ethylene oxide or propylene oxide to the above partially esterified compound;
Examples thereof include saponified products of ethylene-vinyl acetate copolymer, polyvinyl alcohol, polyolefin-based oligomers having two or more hydroxyl groups, and polymers having two or more hydroxyl groups such as ethylene-hydroxyethyl (meth) acrylate copolymer. The melting point of the polyhydric alcohol compound is 3
It is preferably 00 ° C or lower. Further, these polyhydric alcohol compounds may be used in combination of two or more kinds at the same time.

Particularly preferred as the polyhydric alcohol compound which is the component (2) is at least one compound selected from the following polyhydric alcohols. These compounds, in addition to having a function as a so-called cross-linking agent, impart heat stability to the adhesive resin composition according to the present invention, and when molding at a relatively high temperature, gel, lumps, etc. are formed in the molded body. Has the action of preventing the occurrence of. First, the following general formula (I) (R ¹ ) _a C (CH ₂ OH) _b (I) [wherein R ¹ is hydrogen, a chain or cyclic alkyl group having 1 to 12 carbon atoms or an aralkyl group] And a is 0
Represents an integer of 2, b represents an integer of 2 to 4, and a + b
= 4 is selected. Or the following general formula _{(II) CH 2 (OH)} CH (OH) CH 2 O [CH 2 CHOHCH 2 O] m H (II) [ wherein, m is an integer of 0. Polyhydric polyoxyalkylene compound having a structure obtained by adding ethylene oxide or propylene oxide to an alcohol compound, and Formula ^{(III) R 2 -COOH (III} ) [ wherein represented by], R ² is 2 carbon atoms 25 chain alkyl groups, cyclic alkyl groups, aralkyl groups or alkenyl groups are shown. ] One or more of polyglycerin esters having two or more hydroxyl groups in the molecule, which are obtained by dehydration condensation of the organic carboxylic acid compound represented by the above and the polyglycerin represented by the general formula (II). .

The above-mentioned polyoxyalkylene compound is easily prepared by addition reaction of poly (methylol) represented by the general formula (I) or polyglycerin represented by (II) with ethylene oxide or propylene oxide. Can be obtained. Here, as the polymethylol represented by the general formula (I), for example, 1,3-dihydroxypropane; 2,2-dimethyl-1,3-dihydroxypropane; trimethylolethane; 1,1,1-trimethylol Propane; 1,1,1-trimethylolhexane;
1,1,1-trimethylol dodecane; 2-cyclohexyl-2-methylol-1,3-dihydroxypropane; 2- (p-methylphenyl) -2-methylol-
1,3-dihydroxypropane; pentaerythritol and the like. Examples of the polyglycerin represented by the general formula (II) include glycerin, diglycerin, hexaglycerin, octaglycerin, decaglycerin and the like. Polyoxyalkylene compounds obtained by adding ethylene oxide or propylene oxide to these compounds are usually extremely difficult to obtain as a single compound, and are generally obtained as a mixture of compounds having different structures, It can be used without any problem for the purpose of the present invention. Furthermore, a polyoxyalkylene compound obtained by simultaneously adding ethylene oxide or propylene oxide to two or more polyhydric alcohol compounds represented by the general formulas (I) and / or (II) may be used.

The addition amount of ethylene oxide or propylene oxide to the compound represented by the general formula (I) or (II) depends on the number of hydroxyl groups contained in the above-mentioned compound to be used, and therefore cannot be generally specified. Although not possible, it is preferable to add at least 2 mol of ethylene oxide or propylene oxide to at least 1 mol of the above compound. The upper limit of the addition amount is not particularly limited, but in general, when the addition amount exceeds 50 mols relative to 1 mol of the polyhydric alcohol represented by the general formula (I) or (II), the polyoxyalkylene compound obtained is This is not preferable because the molecular weight becomes too large, the mixing property at the time of adjusting the composition decreases, and problems such as bleeding after molding occur.

The polyglycerin ester has the general formula (III)
Can be easily prepared by dehydration condensation of an organic carboxylic acid represented by or its equivalent (eg, an alkali metal salt, an acid halide, etc.) and polyglycerol represented by the general formula (II) by a generally known method. Can be manufactured. Examples of the organic carboxylic acid of the general formula (III) include acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, hexanoic acid, caprylic acid, capric acid, stearic acid, oleic acid, lauric acid, phenylacetic acid, phenylpropione. Acid, phenylbutyric acid, etc. are mentioned. The polyglycerin ester compound used must have two or more hydroxyl groups in the molecule. Therefore, the amount of the organic carboxylic acid used for esterifying the polyglycerin of the general formula (II) needs to be determined in consideration of the number of hydroxyl groups contained in the polyglycerin.

As the polyglycerin ester compound,
For example, glycerin monostearate, glycerin monooleate, glycerin monolaurate, glycerin monocaprylate, glycerin monohexanoate, glycerin monophenethyl ester, glycerin monopropionate, diglycerin monostearate, diglycerin distearate. , Diglycerin monooleate, diglycerin monohexanoate, diglycerin dioctanoate, tetraglycerin monostearate, tetraglycerin tristearate, tetraglycerin tetrastearate, tetraglycerin trihexanoate, tetraglycerin monophenethyl Ester, hexaglycerin monostearate, hexaglycerin distearate, hexaglycerin pentastearate, hexaglycerin triolee Door, hexa-glycerin monolaurate, hexa-glycerin penta laurate, decaglycerol monostearate, decaglycerol octa stearate, decaglycerol pentaoleate, decaglycerol dilaurate, penta decaglycerol distearate,
Examples include pentadecaglycerin decaoleate and octadecaglycerin tetrastearate. Two or more of these polyglycerin esters can be used in combination.

The amount of the polyhydric alcohol compound used as the component (2) is such that the polyhydric alcohol compound is used with respect to the unit derived from the radical-polymerizable acid anhydride contained in the ethylene copolymer of the component (1). It is necessary that the molar ratio of the unit of the hydroxyl group contained in is in the range of 0.01 to 10, and 0.0
It is preferably in the range of 5 to 5. This molar ratio is 0.
When it is less than 01, it is insufficient to introduce the crosslinked structure into the composition in an effective amount. On the other hand, when the molar ratio exceeds 10, it is not preferable because it is meaningless in effectively introducing the crosslinked structure and also the cost becomes high.

The reaction accelerator, which is the component (3) of the present invention, means that the carbonyl group contained in the unit derived from the radical-polymerizable carboxylic acid anhydride contained in the ethylene copolymer is activated, and the hydroxyl group and the acid are combined. It is a compound that accelerates the reaction with an anhydride. There are various kinds of reaction accelerators, and an example thereof is a metal salt of an organic carboxylic acid. As the metal salt of an organic carboxylic acid, a metal salt of a fatty acid having 1 to 30 carbon atoms, for example, acetic acid, butyric acid, octanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, behenic acid, Aliphatic carboxylic acids such as octenoic acid, erucic acid, elaidic acid, adipic acid, malonic acid, succinic acid, glutaric acid, citric acid, tartaric acid, malic acid, diglycolic acid; benzoic acid, chlorobenzoic acid, anisic acid, amino Aromatic carboxylic acids such as benzoic acid, phthalic acid, terephthalic acid, naphthoic acid, naphthalenedicarboxylic acid, and benzenetricarboxylic acid, and metals of Group IA, IIA, IIB, and IIIB of the periodic table (for example, Li, Na, K , Mg, Ca, Zn, Al
Etc.). More specific examples are lithium acetate, sodium acetate, magnesium acetate, aluminum acetate, potassium butyrate, calcium butyrate, zinc butyrate, sodium octanoate, calcium octanoate, potassium decanoate, magnesium decanoate, zinc decanoate, and lauric acid. Lithium, sodium laurate, calcium laurate, aluminum laurate, potassium myristate, sodium myristate, aluminum myristate, sodium palmitate, zinc palmitate, magnesium palmitate, sodium stearate, potassium stearate, calcium stearate, stearic acid Metal salts of aliphatic carboxylic acids such as zinc, sodium oleate and sodium behenate; sodium benzoate, zinc benzoate, sodium phthalate Aluminum phthalic acid, magnesium terephthalate, and metal salts of aromatic carboxylic acids such as naphthalene calcium dicarboxylic acid. Of these, lithium laurate, sodium laurate, calcium laurate,
Aluminum laurate, potassium myristate, sodium myristate, aluminum myristate, sodium palmitate, zinc palmitate, magnesium palmitate, sodium stearate, potassium stearate, calcium stearate, zinc stearate, sodium oleate are preferred. .

Another example of the metal salt of an organic carboxylic acid is a polymer having a metal salt structure of a carboxylic acid. Such polymers include ethylene and radically polymerizable carboxylic acids of Group IA, Group IIA, Group IIB, and Group IIIB metals (eg, Li, Na, K, Mg, Ca, Zn, Al, etc.).
Examples thereof include those having a structure in which a salt is copolymerized, and those having a structure in which a metal salt of ethylene and a radical-polymerizable carboxylic acid and another radical-polymerizable carboxylic acid and / or a derivative thereof are multi-component copolymerized.

Further, a metal salt of the radical-polymerizable unsaturated carboxylic acid (free unsaturated carboxylic acid is graft-polymerized on a polyolefin resin such as polyethylene, polypropylene or ethylene-propylene copolymer, and then neutralized. Which has a structure obtained by graft polymerization of
One having a structure in which a metal salt of a radically polymerizable carboxylic acid and another radically polymerizable carboxylic acid and / or a derivative thereof are simultaneously co-grafted with a polyolefin polymer is mentioned. The radical-polymerizable carboxylic acid and its derivative used here include (meth) acrylic acid, maleic acid, fumaric acid, monomethyl maleate, monomethyl fumarate, monoethyl maleate, monoethyl fumarate, monobutyl maleate, monobutyl fumarate. , Methyl (meth) acrylate, dimethyl maleate, dimethyl fumarate, diethyl maleate, diethyl fumarate, dibutyl maleate, dibutyl fumarate and the like.

Other examples of the reaction accelerator relating to the present invention include tertiary amine compounds such as trimethylamine, triethylamine, dimethylethylamine and diethylcyclohexylamine. Other examples of the reaction accelerator relating to the present invention include, for example, tetramethylammonium tetrafluoroborate, tetramethylammonium hexafluorophosphate, tetramethylammonium bromide, tetraethylammonium bromide, tetraethylammonium iodide, methyltri-n-butylammonium. Examples thereof include quaternary ammonium salts such as chloride, tetrabutylammonium bromide and tetrahexyl ammonium bromide. Further, as another example of the reaction accelerator according to the present invention, for example, metal hydroxides such as calcium hydroxide, magnesium hydroxide and aluminum hydroxide, and metal halides such as calcium chloride, calcium bromide and magnesium chloride. Or a metal salt of oxo acid such as sodium nitrate, calcium nitrate, calcium phosphate, sodium carbonate, calcium carbonate, magnesium carbonate, sodium sulfate, zinc sulfate, potassium chlorate and sodium iodate, and further NaBF ₄ ,
KPF ₆ , NaPCl ₆ , NaFeCl ₄ , NaSnCl ₄ , NaSbF ₆ , NaAsF ₆ ,
Examples include Lewis acid metal salts such as KAsCl ₆ and organic sulfonic acid metal salts such as sodium paratoluate sulfonate, potassium paratoluate sulfonate, aluminum chloroethane sulfonate, calcium ethyl methane sulfonate, zinc ethyl ethane sulfonate, etc. You can

Of the above-exemplified reaction accelerators, metal salts of polymers containing carboxyl groups and metal salts of organic carboxylic acids are preferably used. Further, two or more of the above-mentioned various reaction accelerators may be used in combination, if necessary. The amount of the reaction accelerator used in the present invention must be in the range of 0.001 to 20 parts by weight, and is in the range of 0.01 to 15 parts by weight, based on 100 parts by weight of the ethylene copolymer. It is preferable. If this amount is less than 0.001 part by weight, the reaction becomes too slow, and it becomes difficult to effectively introduce a crosslinked structure into the composition. If it exceeds 20 parts by weight, the reaction rate is improved. Not only is it meaningful, but it is also economically unfavorable.

The heat-resistant heat-sensitive adhesive relating to the present invention includes
A polyolefin resin can be added as a component (4) to the composition comprising (1), (2) and (3). Specific examples of the polyolefin-based resin here include low-density polyethylene, high-density polyethylene,
Polypropylene, polyisoprene, polyisobutylene,
Polybutene, poly-3-methylbutene-1, poly-4-
2 to 1 carbon atoms such as methylpentene-1 and polybutadiene
Mention may be made of homopolymers of zero saturated hydrocarbon monomers. Further, a copolymer of two or more kinds of monomers selected from the monomers constituting these homocopolymers and other olefins, or the monomers constituting the above homocopolymers or other Copolymers of olefins with other radically polymerizable monomers that do not have acid anhydrides, such as ethylene-propylene; styrene-butadiene copolymers; ethylene-propylene-diene terpolymers; butene-1, hexene-1, octene −
Linear low-density polyethylene containing 1,4-methylpentene-1 as a comonomer; propylene-ethylene block copolymer; copolymer of ethylene and unsaturated carboxylic acid or its derivative (for example, ethylene-vinyl acetate copolymer). Polymers, ethylene- (meth) acrylic acid ester copolymers, etc.) can be mentioned. Furthermore, a mixture of each of the above resins can be used.

The polyolefin resin used here has the purpose of being a resin for diluting the heat-resistant heat-sensitive adhesive comprising the above (1), (2) and (3), and also has a high temperature (80 ° C. or higher) after adhesion. ), A crystalline melting point of 100 ° C. or higher (the melting point referred to here is DS
By selecting one having a melting peak temperature (measured by an instrument such as C, DTA, etc.), it can play an auxiliary role to achieve that purpose. That is, by adding the polyolefin resin, it is possible to more efficiently exhibit the contradictory performance of having low-temperature adhesiveness and capable of maintaining a certain degree of adhesive strength even after being adhered at a high temperature. The amount of the polyolefin resin used as the component (4) is the same as those of the components (1), (2) and (3).
5 to 8 based on 100 parts by weight of the total resin composition
It is in the range of 0 parts by weight. The amount of polyolefin used is 80
If it exceeds the weight part, the amount of the component (1), which is originally capable of exhibiting adhesion with other substrates, contained in the heat-resistant heat-sensitive adhesive is too small, and therefore the adhesiveness of the heat-resistant heat-sensitive adhesive obtained is low. It is not preferable because it significantly decreases. When the amount is less than 5 parts by weight, it is meaningless to mix the polyolefin resin.

The heat-resistant heat-sensitive adhesive relating to the present invention contains various additives within a range that does not impair the characteristics of the adhesive.
It is possible to use compounding agents and fillers. Specific examples of these are antioxidants (heat stabilizers), ultraviolet absorbers (light stabilizers), antistatic agents, antifogging agents, flame retardants, lubricants (slip agents, antiblocking agents), glass fillers, etc. Inorganic fillers, organic fillers, reinforcing agents, colorants (dyes, pigments), foaming agents, fragrances, and the like.

In order to produce the heat-resistant heat-sensitive adhesive according to the present invention, the components (1) to (3) and the polyolefin resin or additives used as required may be mixed by various means. . As a mixing method, a generally known mixing method of various resins can be used. For example, dry blending may be performed using a mixer such as a Henschel mixer or a tumbler, and melt kneading may be performed using a mixer such as a Banbury mixer, a static mixer, a pressure kneader, an extruder, or a roll mill. At this time, a uniform composition can be obtained by previously dry blending and melt-kneading the resulting mixture. Further, when molding the heat-resistant heat-sensitive adhesive according to the present invention, the components are mixed (dry blended) in the form of pellets or powder, and the process of manufacturing a film or the like is used in an extruder or an injection molding machine. It can also be melt mixed.

The use of the heat-resistant heat-sensitive adhesive according to the present invention makes it possible to bond various base materials at a relatively low processing temperature to obtain a multilayer laminate. Examples of such an adherable substrate include high-quality paper, kraft paper, glassine paper, Japanese paper, and corrugated cardboard base paper. There is no particular limitation on the base material constituting the multilayer laminate according to the present invention,
Various kinds of paper such as synthetic paper, art paper, coated paper; cotton, linen,
Various woven or non-woven fabrics made of polyester, nylon, etc .; wooden boards; various metal plates or foils of iron, aluminum, copper, tinplate, etc .; polypropylene, polystyrene, polyethylene, polyester, nylon, polycarbonate, acrylic resin, phenolic resin, polyurethane, styrene- Examples include plates, molded products, films or foams formed from various plastics such as butadiene block copolymers and styrene-acrylonitrile copolymers; various inorganic substances such as glass fibers and ceramics. Further, these base materials may be subjected to surface treatment, printing, coating, etc., if necessary.

The multilayer laminate of the present invention is particularly suitable for interior materials of automobiles and the like which use a skin material and a substrate material as a base material (for example, an automobile interior ceiling material, an automobile interior door member, an automobile interior dashboard member). , Automotive interior console boxes, automotive interior instool panel members, etc.) or interior materials for vehicles, ships, houses, etc. The skin material and substrate material used here are not particularly limited, and various materials generally used as interior materials for automobiles, vehicles, ships, houses, etc. can be used. As a specific example of such a skin material,
Polyester non-woven fabric, brushed knit, fabric, suede-like synthetic leather, vinyl chloride (polyvinyl chloride) leather, polyurethane leather, polypropylene thermoplastic elastomer, or these materials with a cushioning material such as urethane foam, polyethylene foam or polypropylene foam attached Etc. On the other hand, specific examples of the substrate material include resin felt, resin wood, phenol resin plate containing glass fiber, corrugated board, polypropylene honeycomb, polystyrene foam, glass fiber reinforced polypropylene plate, AB.
Examples thereof include an S resin plate, an AS resin plate, and those obtained by laminating a non-woven fabric to these.

Various molding methods can be employed in producing the multilayer laminate according to the present invention. For example, a substrate material is heated to a predetermined temperature, set in a vacuum forming machine, a heat-resistant heat-sensitive adhesive filmed by inflation molding or T-die molding is placed on the substrate, and then a skin material which is heated to a predetermined temperature in advance. And heat-pressing the above film between the skin material and the substrate material; heat-pressing or laminating the skin material with a heat-resistant heat-sensitive adhesive by extrusion laminating Method of hot pressing with a hot roll;
The heat-resistant heat-sensitive adhesive according to the present invention is crushed into a powder,
A method of sprinkling a substrate material placed on a hot press and hot pressing a skin material thereon; and further, laminating the above film on the adhesive side of the skin material in advance with a heat roll and then heating with a heat press or a heat roll. Examples of the method include pressure bonding.

In the above-described method for producing the multilayer laminate of the present invention, the heating temperature differs depending on the skin material used, the type of the substrate material, the molding conditions, and the composition of the heat-resistant heat-sensitive adhesive, but cannot be unconditionally specified. The temperature is at least the softening point of the heat-resistant heat-sensitive adhesive and is not higher than the temperature at which the skin material and the substrate material are not affected. The heat-resistant heat-sensitive adhesive according to the present invention which functions as an adhesive layer is 60 to 130.
It has a relatively low crystal melting point of about 0 ° C., and is capable of strong adhesion at a relatively low pressure of about 0.1 to 2.0 kg / cm ^{2 in} pressure bonding. It can be manufactured without damaging the texture and feel of the material.

The thickness of each layer of the multilayer laminate of the present invention varies depending on its material, application, required physical properties and the like and is not particularly limited, but the adhesive layer comprising the heat-resistant heat-sensitive adhesive according to the present invention is 10 To 200 μm, preferably 20 to 100 μm
Is. Here, if it is less than 10 μm, the adhesive strength becomes insufficient, which is not preferable, and if it exceeds 200 μm, the thermal conductivity is lowered and the adhesive strength cannot be obtained, which is not practical. The multilayer laminate of the present invention is composed of at least the above-mentioned two layers or three layers, but, if necessary, further via an adhesive layer comprising the heat-resistant heat-sensitive adhesive according to the present invention,
Alternatively, it may be a laminated body in which another material is laminated with or without another adhesive layer. Less than,
The present invention will be specifically described with reference examples, examples, and comparative examples.

[0034]

【Example】

<Reference Example 1> Using equipment of a high-pressure low-density polyethylene production plant, polymerization temperature 190 ° C, polymerization pressure 1900K
An ethylene-based copolymer (A), which is an ethylene-methyl acrylate-maleic anhydride terpolymer, was produced under the condition of g / cm ² . MFR of this ethylene copolymer
(JIS-K7210, Table 1, Condition 4) was 10, the content of units derived from methyl acrylate was 25% by weight, and the content of units derived from maleic anhydride was 1.6% by weight. The composition of the comonomer was determined by infrared absorption spectrum.

Reference Example 2 Ethylene / methyl methacrylate / itaconic anhydride terpolymer under the conditions of a polymerization temperature of 190 ° C. and a polymerization pressure of 1900 Kg / cm ² using equipment of a high pressure low density polyethylene production plant. To produce an ethylene-based copolymer (B). The MFR of this ethylene copolymer (JIS-K7210, Table 1, condition 4) is 2
0, the content of units derived from methyl methacrylate is 20
The content of the unit derived from itaconic anhydride is 3% by weight.
It was 5% by weight. The composition of the comonomer was determined by infrared absorption spectrum.

<Reference Example 3> An ethylene-methyl acrylate-maleic anhydride terpolymer was used under the conditions of a polymerization temperature of 200 ° C. and a polymerization pressure of 1900 Kg / cm ² using equipment of a high-pressure low-density polyethylene production plant. An ethylene-based copolymer (C) was produced. The ethylene-based copolymer had an MFR of 8 (JIS-K7210, Table 1, Condition 4), a content of units derived from methyl acrylate was 18% by weight,
The content of units derived from maleic anhydride is 2.5% by weight
Met. The composition of the comonomer was determined by infrared absorption spectrum.

<Reference Example 4> An ethylene-butyl acrylate-maleic anhydride terpolymer was used under the conditions of a polymerization temperature of 200 ° C. and a polymerization pressure of 1800 Kg / cm ² using equipment of a high-pressure low-density polyethylene manufacturing plant. An ethylene-based copolymer (D) was produced. The ethylene-based copolymer had an MFR (JIS-K7210, Table 1, Condition 4) of 8, and a butyl acrylate-derived unit content of 16% by weight.
Content of units derived from maleic anhydride is 1.5% by weight
Met. The composition of the comonomer was determined by infrared absorption spectrum.

<Reference Example 5> An ethylene-vinyl acetate-maleic anhydride terpolymer was prepared using a high-pressure low-density polyethylene plant at a polymerization temperature of 200 ° C. and a polymerization pressure of 1800 Kg / cm ^2. An ethylene copolymer (E) was produced. MFR of this ethylene copolymer
(JIS-K7210, Table 1, Condition 4) was 15, the content of units derived from vinyl acetate was 20% by weight, and the content of units derived from maleic anhydride was 2.5% by weight.
The composition of the comonomer was determined by infrared absorption spectrum.

<Example A> (Example A1) The ethylene-based copolymer (A) 8 of Reference Example 1
9.5% by weight, trimethylolpropane (hereinafter abbreviated as TMP) 0.5% by weight as a polyhydric alcohol, and a Zn salt of ethylene-methacrylic acid copolymer (methacrylic acid content 10% by weight) as a reaction accelerator ( After neutralizing 20 mol% of the units derived from methacrylic acid) 10 wt% by dry blending with a Henschel mixer, melt kneading at 190 ° C. using a 37 mmφ co-directional twin-screw extruder to form pellets of heat-resistant heat-sensitive adhesive. Obtained. The contents of this formulation are shown in Table 1.

(Examples A2 to A11) Example A1 using the components (1), (2), (3) and (4).
The same procedure was followed to obtain heat-resistant heat-sensitive adhesive pellets.
The content of the formulation is shown in Table 1.

(Comparative Example A1) The procedure of Example A1 was repeated, except that the reaction accelerator of component (3) was not added,
An adhesive pellet was obtained. The content of the formulation is shown in Table 1.

Comparative Example A2 An adhesive pellet was obtained in the same manner as in Example A1 except that the polyhydric alcohol of component (2) was not added. The content of the formulation is shown in Table 1.

(Comparative Example A3) Same as Example A1 except that ethylene-methyl methacrylate binary copolymer (methyl methacrylate content = 20% by weight, MFR = 3) was used as the component (1). To obtain pellets of the adhesive. The content of the formulation is shown in Table 1.

(Comparative Examples A4 and A5) Adhesive pellets were obtained in the same manner as in Example A1 except that the amounts of components (2) and (3) were changed. Table 1 shows the composition
It was shown to.

<Example B> (Example B1) The heat-resistant heat-sensitive adhesive obtained in Example A1 was formed into a film having a thickness of 70 μm by a film forming machine with a T-type die having an extruder of 25 mmφ and a width of 20 cm. I got a film of. Using this film as the adhesive layer, the base materials (skin material and substrate material) actually used in the interior materials for automobiles were adhered, and the adhesiveness was tested. Polyethylene terephthalate (PET) non-woven fabric was used as the skin material, and resin felt (RF) was used as the substrate material. Adhesive is the upper plate 120
℃, lower plate 70 ℃ set to the hot press, from the top of the skin material,
The above film and substrate material are sandwiched in this order, and the actual surface pressure is 2.5.
It was pressure bonded under the conditions of Kg / cm ² and 10 seconds. The size of the press of the substrate material was 10 cm × 20 cm. After bonding, 2
After conditioning for 24 hours at 3 ° C and 50% relative humidity, 25
Cut into a test piece with a width of mm and use a tensile tester at room temperature (2
180 ° peeling test at 3 ° C (peeling speed 200 mm
/ Min). As a general rule, peeling strength (g /
25 mm) was measured, but when the skin material or the substrate material was broken before peeling, the strength at the time of breaking was measured. Further, as a heat-resistant creep test, a load of 100 g was suspended on a test piece that had been partially peeled, and the peeling distance (mm) was measured when the specimen was left in an atmosphere of 80 ° C. for 24 hours, and used as a measure of heat resistance. The value of the adhesive strength is an average value (maximum, minimum 2 point cut) of 5 test pieces. The heat resistance is an average value of three test pieces. Table 2 shows the results.

(Examples B2 to B11) As shown in Table 2, the same operation as in Example B1 was carried out except that the kinds of the heat-resistant heat-sensitive adhesive for the adhesive layer, the skin material and the substrate material were changed. Table 2 shows the results.

(Example B12) Using the film obtained in Example B3, a 2 mm-thick foamed polypropylene (PP-based TPO / foamed PP) coated with 0.2 mm PP-based thermoplastic elastomer as a skin material was used. Glass fiber reinforced styrene-acrylonitrile copolymer (ASG) as plate material
The board was tested for adhesion. Adhesion is first 130 ℃
The outer skin and the film were sandwiched between the Teflon-coated rolls heated in the above, and the rolls were heat-rolled at a speed of 5 m / min to bond them. Next, the substrate material was heated to 70 ° C. for 5 minutes and the skin was heated to 120 ° C. and bonded by a vacuum bonding method. Table 2 shows the results.

(Examples B13 to B18) As shown in Table 2, the same operation as in Example B12 was performed except that the kinds of the heat-resistant heat-sensitive adhesive for the adhesive layer, the skin material and the substrate material were changed. Table 2 shows the results.

(Comparative Examples B1 to B5) Comparative Example A1 or A
A film was produced from the pellets obtained in Example 5 in the same manner as in Example B1. Using this film as an adhesive layer, as shown in Table 2, the types of skin material and substrate material were changed, and the same operation as in Example B1 was performed. Table 2 shows the results.

(Comparative Examples B6 and B7) Comparative Examples A1 and A3
A film was produced from the pellets obtained in 1. above in the same manner as in Example B1. Using this film as an adhesive layer,
As shown in Table 2, changing the types of skin material and substrate material,
It operated like Example B12. Table 2 shows the results.

Looking at the results of the above tests, Examples B1-B
In No. 11, it can be seen that the multilayer laminate using the heat-resistant heat-sensitive adhesive according to the present invention exhibits excellent adhesive strength even in the hot pressing method under the conditions of low base material temperature and low surface pressure.
In addition, in Examples B12 to B18, the multilayer laminate using the heat-resistant and heat-sensitive adhesive according to the present invention can be practically used even in the vacuum bonding method in which the bonding pressure is lower and the bonding time is shorter than the hot pressing method. It can be seen that strength and heat resistance can be obtained.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

As described above, the heat-resistant heat-sensitive adhesive according to the present invention can be applied to various base materials, especially automobiles, vehicles, ships,
It is possible to laminate skin materials and substrate materials used as interior materials for houses and the like under conditions of relatively low temperature and low pressure, and yet exhibit high adhesive strength. Therefore, since the multilayer laminate using the heat-resistant heat-sensitive adhesive in the adhesive layer has excellent adhesive workability and workability and can be processed at low temperature, the texture of the skin material is not impaired and the aesthetics are high. It can be suitably used as an interior material for automobiles, vehicles, ships, houses, and other buildings.

Claims (5)

[Claims] 1. A multi-component copolymer comprising (1) ethylene, a radical-polymerizable acid anhydride and a radical-polymerizable comonomer other than ethylene, wherein the proportion of units derived from the radical-polymerizable acid anhydride in the copolymer. Is 0.1% by weight or more and 5% by weight
Hereinafter, an ethylene copolymer in which the proportion of units derived from other radically polymerizable comonomer is 10% by weight or more and 50% by weight or less, (2) a polyhydric alcohol compound having at least two hydroxyl groups in the molecule, (3) The molar ratio of the hydroxyl group unit in the polyhydric alcohol compound as the component (2) to the unit derived from the radical-polymerizable acid anhydride in the component (1) is 0.01, which is composed of a reaction accelerator. It is in the range of 10 to 0.00, and the reaction accelerator which is the component (3) is 0.00 relative to 100 parts by weight of the ethylene copolymer which is the component (1).
A heat-resistant heat-sensitive adhesive in the range of 1 to 20 parts by weight. 2. The polyhydric alcohol compound which is the component (2) has the following general formula (I) (R ¹ ) _a C (CH ₂ OH) _b (I) [wherein R ¹ is hydrogen and the number of carbon atoms is 1 to 12 chain or cyclic alkyl groups or aralkyl groups are represented, and a is 0 to
Represents an integer of 2, b represents an integer of 2 to 4, and a + b
= 4 is selected. Or the following general formula _{(II) CH 2 (OH)} CH (OH) CH 2 O [CH 2 CHOHCH 2 O] m H (II) [ wherein, m is an integer of 0. Polyhydric polyoxyalkylene compound having a structure obtained by adding ethylene oxide or propylene oxide to an alcohol compound, and Formula ^{(III) R 2 -COOH (III} ) [ wherein represented by], R ² is 2 carbon atoms 25 chain alkyl groups, cyclic alkyl groups, aralkyl groups or alkenyl groups are shown. ] One or more of polyglycerin esters having two or more hydroxyl groups in the molecule, which are obtained by dehydration condensation of the organic carboxylic acid compound represented by the above and the polyglycerin represented by the general formula (II). The heat-resistant heat-sensitive adhesive according to claim 1. 3. The heat-resistant heat-sensitive adhesive according to claim 1, wherein the reaction accelerator as the component (3) is a metal salt of a polymer containing a carboxyl group or a metal salt of an organic carboxylic acid. 4. A heat-resistant heat-sensitive adhesive containing 5 to 80 parts by weight of a polyolefin resin (4) with respect to 100 parts by weight of the composition according to claim 1. 5. A multilayer laminate having a base material layer and an adhesive layer, the adhesive layer comprising the heat-resistant and heat-sensitive adhesive according to any one of claims 1 to 4.