JPH05193067A - Laminating material - Google Patents

Abstract

PURPOSE:To provide a laminating material bondable at a temp. as low as possible and under a low pressure as low as possible, having high bonding strength and high temp. creep resistance to a wide range of various objects and capable of being simply released at temp. of recycle treatment while keeping sufficiently high bonding strength at usual use temp. CONSTITUTION:A multilayered laminated material contains a resin layer composed of a resin compsn. consisting of 10-90wt.% of an ethylenic copolymer (1) composed of a multi-unit copolymer consisting of ethylene, a radical polymer acid anhydride and a comonomer and characterized in that the ratio of a unit originating from the acid anhydride in the copolymer is 0.1-5wt.% and the ratio of the unit originating from other comonomer is 3-50wt.% and 90-10wt.% of a polyolefinic resin (2) with an m.p. of 100 deg.C or higher.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminate material having high strength, easy adhesion, heat resistance and excellent recyclability, and more particularly to a laminate material suitable for use as an automobile interior material.

[0002] Motor vehicles are exported to countries around the world, are exposed to extremely cold to hot weather, and have a wide variety of uses. Especially, in the direct sunlight, the inside thereof becomes extremely hot compared with the outside temperature. Well known. And various composite materials are used as interior materials in the car to improve comfort and appearance (aesthetics). However, even if they function as interior materials for automobiles, they are Interior materials with excellent recyclability are required.

[0003]

2. Description of the Related Art As a laminated material, especially an automobile interior material, a multilayer laminated body is used in which a skin material that emphasizes indoor aesthetics and a substrate material that emphasizes necessary functions are adhesively bonded.
In manufacturing the multi-layer laminate, joining with a solvent-based adhesive takes time and labor, and in recent years, environmental issues are becoming more important, and problems of industrial hygiene and danger (fire, etc.) due to organic solvents. There is an inappropriate working method.

In order to avoid this problem, a heat-sensitive adhesive resin is often used for bonding the skin material and the substrate material. As a specific method, a heat-sensitive adhesive film is sandwiched between a skin material and a substrate material and heat-pressed by a heat press, or a laminated material or a skin-coated material obtained by extruding and coating a heat-sensitive adhesive resin on the skin material. A method such as heating and laminating a laminated material obtained by hot roll laminating the film of
Furthermore, a method of vacuum forming these skin agents is adopted.

[0005] These multilayer laminates have a means of adhering a skin material for enhancing comfortability and aesthetics and a substrate material for maintaining functionality with a thermoplastic resin. On the other hand, the temperature at the time of bonding is as low as possible so that the woven fabric or foam used as the skin material is not affected, and it is possible to bond in a short time with low pressure. In addition, it is required to have a strong adhesion to the substrate material, low cost, and good high temperature creep property. In particular, there are normally conflicting requirements for good low-temperature adhesiveness and good high-temperature creep properties (generally good low-temperature adhesiveness deteriorates high-temperature creep properties).

Further, at the time of recycling, these interior materials are disassembled and separated as easily as possible to separate recyclable materials and non-recyclable materials, or separate each for separately applying to an advantageous disposal method. However, it is difficult to peel and disassemble the materials because nylon resins and curable adhesives that have excellent heat resistance and high temperature creep properties have been used in the past. It wasn't done to handle this.

[0007]

DISCLOSURE OF THE INVENTION The present invention is capable of bonding at a temperature as low as possible with a low pressure-bonding force, has a strong room-temperature adhesion to a wide variety of adherends, a high-temperature creep resistance, and a film. There is no blocking property,
Laminated material that is a thermoplastic resin with excellent workability and economy, and has sufficient adhesive strength at normal use temperatures but can be easily peeled at the temperature of recycling treatment (has easy peelability). For the development of.

[0008]

Means for Solving the Problems As a result of various investigations for solving the above problems, the present inventors have found that a specific polyolefin-based resin composition is used as an adhesive layer to cover a skin material, a thermoplastic resin, and a substrate material. It has been found that the multi-layered laminated body is a suitable material that can be widely used as a laminated material.

That is, the present invention provides a multilayer structure comprising at least a skin material, a thermoplastic resin and a substrate material, wherein the thermoplastic resin is a polyolefin resin composition comprising the following (1) and (2): Characteristic laminated material. (1) A multi-component copolymer composed of ethylene, a radical polymer acid anhydride, and a radical-polymerizable comonomer other than this, 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 or less, and the ratio of units derived from other radical polymer comonomer is 3% by weight
10 to 50% by weight of the above ethylene-based copolymer
90% by weight and (2) a polyolefin resin 90 having a melting point of 100 ° C. or higher.
The above problems were solved by developing 10 to 10% by weight.

The present invention will be described in detail below. There is no particular limitation on the skin material and the substrate material relating to the present invention, and various materials that are currently generally used as a laminate material, particularly as a laminate material for automobile interiors can be used.

Specific examples of such a skin material include a polyester non-woven fabric, a raised knit, a vinyl chloride leather, a polyurethane leather, a polypropylene thermoplastic elastomer, or a cushioning material such as urethane foam, polyethylene foam or polypropylene foam in these materials. Various materials, such as those bonded together, can be used.

Specific examples of the substrate material include resin felt, phenol resin plate containing glass fiber, corrugated board, polypropylene honeycomb, polystyrene foam, glass fiber reinforced polypropylene plate, or a material obtained by laminating a nonwoven fabric to these.

The polyolefin resin composition according to the present invention comprises two components, one of which is a multi-component copolymer comprising ethylene and a radical-polymerizable acid anhydride and a radical-polymerizable comonomer. The adhesiveness with the skin material and the substrate material is expressed by. The radical-polymerizable acid anhydride as used herein is a compound that has at least one radical-polymerizable unsaturated bond and at least one acid anhydride group in the molecule, and can introduce an acid anhydride group into the molecule by polymerization. Indicates. Specific examples of the compound include maleic anhydride, itaconic anhydride, endic acid anhydride, citraconic anhydride, 1-butene-3,4-dicarboxylic acid anhydride, and dicarboxylic acid at the terminal having at most 18 carbon atoms. Examples thereof include alkenyl succinic anhydride having a heavy bond, and alkadienyl succinic anhydride having a double bond at the terminal having at most 18 carbon atoms. These may be used in combination of two or more kinds at the same time. Of these, maleic anhydride and itaconic anhydride are particularly preferable.

Many compounds can be used as the radical-polymerizable comonomer, and specifically, an ethylenically unsaturated ester compound, an ethylenically unsaturated amide compound, an ethylenically unsaturated acid compound, an ethylenically unsaturated ether compound, an ethylene type An unsaturated hydrocarbon compound etc. can be mentioned. If these are specifically described, examples of the ethylenically unsaturated ester compound include vinyl acetate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylate. ) Hexyl acrylate, octyl acrylate, (meth)
Examples thereof include lauryl acrylate and benzyl (meth) acrylate. Examples of the ethylenically unsaturated amide compound include (meth) acrylamide and 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-
Examples thereof include dimethyl (meth) acrylamide and N, N-diethyl (meth) acrylamide. Examples of the ethylenically unsaturated acid compound include (meth) acrylic acid. Ethylenically unsaturated ether compounds include methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether,
Examples thereof include octadecyl vinyl ether and phenyl vinyl ether. Ethylenically unsaturated hydrocarbon compounds and other compounds include styrene and α-
Methylstyrene, acrylonitrile, methacrylonitrile, acrolein, trimethoxyvinylsilane, triethoxyvinylsilane, vinyl chloride, vinylidene chloride and the like can be mentioned. Among these, particularly preferable compounds include (meth) acrylic acid esters and (meth) acrylic acid. If necessary, two or more kinds of these comonomers may be used in combination at the same time.

The proportion of the units derived from the radical-polymerizable acid anhydride and the other radical-polymerizable comonomer in the ethylene copolymer is 0.1 to 5% by weight of the radical-polymerizable acid anhydride, The comonomer should be in the range of 3 to 50% by weight.

If the proportion of the radical-polymerizable acid anhydride is less than 0.1% by weight, the adhesive performance is insufficient and a good multilayer laminate cannot be produced. If the proportion exceeds 5% by weight, the compatibility of the ethylene copolymer and the polyolefin resin is deteriorated and the performance of the product is deteriorated. If the proportion of the other radical-polymerizable comonomer is less than 3% by weight, the crystal melting point of the ethylene-based copolymer will not be sufficiently low, and the low-temperature adhesiveness, which is one of the features of the present invention, cannot be exhibited. On the other hand, if it exceeds 50% by weight, it becomes difficult to handle the resin, and the heat resistance required for the laminated material, particularly for automobile interior materials is deteriorated.

For the production of the ethylene-based copolymer, basically, ordinary low-density polyethylene production equipment and technology can be used. It is generally a bulk polymerization, which is 100 to 3 under a pressure of 700 to 3000 atm.
It is produced by radical polymerization in the temperature range of 00 ° C. The preferred polymerization pressure and polymerization temperature range is 1000 to 2
The pressure may be 500 atm, and the average temperature in the reactor may be 150 to 270 ° C.

The production of the ethylene copolymer used in the present invention is carried out under the above reaction conditions in the presence of at least one free radical initiator. Examples of the free radical initiator include oxygen; di-t-butyl peroxide, t
Dibutyl peroxide such as butyl cumyl peroxide dicumyl peroxide; acetyl peroxide, i
-Diacyl peroxide such as butyl peroxide and octanoyl peroxide, peroxycarbonate such as di-i-propylperoxycarbonate and di-2-ethylhexylperoxycarbonate; t-butylperoxypivalate, t- Butyl peroxy laurate, peroxy ester, etc .; methyl ethyl ketone peroxide, cyclohexanone peroxide, etc., ketone peroxide; 1,1-bis-t-butyl peroxycyclohexane, 2,2-bis-t-butyl peroxy Peroxyketals such as octane; hydroperoxides such as t-butyl hydroperoxide and cumene hydroperoxide; azo compounds such as 2,2-azo-i-butyronitrile and the like.

In the polymerization, various chain transfer agents can be used as a molecular weight regulator. Examples of chain transfer agents include olefins such as propylene, butene and hexene, paraffins such as ethane, propane and butane, carbonyl compounds such as acetone, methyl ethyl ketone and methyl acetate, and aromatic hydrocarbons such as toluene, xylene and ethylbenzene. Etc. can be mentioned.

The thus produced ethylene-based copolymer satisfying the above-mentioned conditions is melted at a relatively low temperature and is rich in physicochemical interaction with various base materials and reactivity, so that the polyolefin of the present invention is used. The resin composition plays a major role in exhibiting high adhesive strength even at low temperature molding.

The target of the polyolefin resin as the second component of the thermoplastic resin is high density polyethylene, low density polyethylene, polypropylene, polyisoprene,
Polybutene, poly-3-methylbutene-1, poly-4-
A copolymer of methyl pentene-1, polybutadiene, and a constitutional unit of the resin, for example, an ethylene-propylene copolymer, butene-1, 4-methylpentene-1, hexene-1, octene-1, etc. as a comonomer. Examples include chain low-density polyethylene, propylene-ethylene block copolymers, and mixtures of these resins.

The polyolefin resin usable in the present invention must have a melting point of 100 ° C. or higher, preferably 100 to 160 ° C., particularly preferably 120 to 150 ° C. The melting point referred to herein means a melting peak temperature measured by a device such as DSC or DTA. The purpose of mixing the polyolefin-based resin with the ethylene-based copolymer is to maintain the adhesive strength (improve the heat-resistant creep property) when used at high temperature, which is required for laminated materials, especially for automobile interior materials, but has a melting point of 100 ° C. If less than, this effect is insufficient.

The polyolefin resin composition according to the present invention is produced by mixing the above two components.
Various commonly known methods can be used for mixing. As a specific method, for example, a method of dissolving each component in a good solvent such as high temperature toluene, reprecipitation, a method of mixing each component in a molten state, that is, a commonly used pressure kneader, roll , Banbury mixer, static mixer, screw type extruder and the like.

In some cases, it is possible to dry-blend each component when molding the resin composition. That is, it is possible to mix the respective components in the form of pellets or powder and melt-mix them by utilizing the kneading action of an extruder or the like in the production stage of the film or the like.

In the composition of the polyolefin resin according to the present invention, various additives, compounding agents and fillers can be used as long as the characteristics of the composition are not impaired. 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 the production of the polyolefin resin composition, the mixing ratio of the two components will vary depending on the finally required requirements, and therefore cannot be specified unconditionally. Generally, it is suitable to produce the composition with the ratio of the ethylene copolymer and the polyolefin resin being in the range of 1/9 to 9/1.

The polyolefin resin composition thus obtained strongly adheres to the skin material and the substrate material without deteriorating the appearance of the skin material by hot pressing at a relatively low temperature, and maintains the adhesive strength at high temperature. Excellent in terms.

When it is required to easily peel off the adhered skin material when reusing or disposing of defective products,
An automobile ceiling, door trim, or the like using the composition of the present invention,
Among polyolefin resin compositions obtained by mixing the above-mentioned two components for interior materials such as instrument panels and console boxes, linear polyethylene, polypropylene materials having a melting point of 120 to 150 ° C. are used as polyolefin resins. It is preferable to use the polyolefin resin composition obtained by using. The composition has excellent adhesion retention at high temperatures expected in automobiles, and surprisingly significantly lowers adhesive strength when the temperature is higher than 140 ° C. This is very significant in peeling defective molded products, etc., and separating and recycling each laminated member.

Various molding methods can be used for producing a laminated material, particularly an automobile interior material, using the polyolefin resin composition. To give a general example, a method in which a polyolefin resin composition is formed into a film by inflation molding or T-die molding, and then sandwiched between a skin material and a substrate material and heat-pressed by a hot press, a method of vacuum molding the same, and a skin material A method of heat-pressing a laminated material obtained by extrusion-coating a polyolefin-based resin composition onto a substrate material with a hot press or a heat roll, and further pulverizing the polyolefin-based resin composition into a powder and then placing the base material on the hot press. It is also possible to use a method in which the plate material is sprinkled, and the skin material is hot-pressed thereon.

The multilayer laminate obtained as described above can be used under harsh environmental conditions and is suitable for applications where appearance is important. For example, specifically, automobile interior ceiling members, automobile interior door members, automobile interior dash. Not only laminated materials for automobile interiors such as board members, but also other vehicles such as trains, ships,
It is preferably used as a laminated material for interiors of aircraft, prefabricated houses and the like.

[0031]

The laminated material of the present invention, especially the laminated material for automobile interiors, can meet the following requirements. Even if it is used in a composite material that includes a high-quality skin material, the texture and feel of the material should not be impaired. The composite material cracks even in extremely cold and hot weather, especially in hot weather.
Do not warp, peel, or deform due to creep. Low cost, low temperature, low pressure and short time bonding are possible in the production process, and excellent at room temperature adhesive strength and high temperature creep resistance for various materials. Adhesive strength is significantly reduced at the recycling temperature, and it is easy to peel off each component.

Among these requirements, low-temperature adhesiveness with high strength and creep resistance at high temperature are contradictory requirements, and in ordinary adhesive resins, when low-temperature adhesiveness is good, high-temperature creep property is poor and high-temperature creep property is high. It was said that low-temperature adhesiveness was reduced when creep properties were good.

Further, the high temperature creep property and the demand that the adhesive strength at the recycling temperature is remarkably lowered are contradictory demands, but the polyolefin resin composition of the present invention overcomes this demand, Laminated material,
In particular, it meets the demand for laminated materials for automobile interiors.
Hereinafter, the present invention will be specifically described with reference to examples.

[0034]

【Example】

(Example 1) As an ethylene-based copolymer, an ethylene-methyl methacrylate-maleic anhydride terpolymer was used. The copolymer uses the equipment of the high-pressure low-density polyethylene plant, and the polymerization temperature is 240 ° C and the polymerization pressure is 1900K.
It was manufactured under the conditions of g / cm ² . MFR of this copolymer
(JIS-K7210, 190 ° C, load 2.16 Kg /
cm ² , hereinafter MFR is 15 under all conditions except for temperature), and the content of units derived from methyl methacrylate is 16
%, The unit derived from maleic anhydride is 2.2% by weight
Met. The composition of the comonomer other than ethylene was determined by infrared absorption spectrum.

As the polyolefin resin, ethylene-
Showa Denko KK Syoallomer FD433 (MFR (230 ° C.) = 9.0, density = 0.894 g / cc, melting point (DSC method) = 135
C) was used. The above two components were dry-blended with a copolymer and a polypropylene resin in a ratio of 40/60, and then melt-kneaded at 190 ° C. with a 37 mmφ co-directional twin-screw extruder to obtain resin composition pellets.

Then, the resin composition was formed into a film having a thickness of 70 μm by an inflation film molding machine having an extruder of 45 mmφ and opened to obtain a film having a width of 80 cm.

This film and the skin material described in Table 1,
An adhesion test was performed using a combination of substrate materials. Adhesion is performed by heating the structural material without load with a heat press set at 210 ° C., and then transferring it to a cooling press at 25 ° C.
Layered in the order of skin materials, and with a surface pressure of 10 kg / cm ² 4
It was crimped for 0 seconds. At the time of pressing, a spacer having an appropriate thickness was used for the purpose of adjusting the finished thickness of the laminated plate and suppressing damage to the skin material. The size of the finished laminate is 10 cm x 20 cm.

After the bonding, the condition was adjusted for 24 hours at 23 ° C. and a relative humidity of 50%, the test piece was cut into a 25 mm width, and a 180 ° peel test (23 ° C.) was carried out by a tensile tester to measure the adhesive strength.

Further, a load of 100 g was suspended on the test piece which was peeled off halfway, and the peeling distance was measured when the specimen was left in an atmosphere of 80 ° C. for 48 hours, and used as a measure of heat-resistant creep resistance. Furthermore, 80 ℃, 100 ℃, 110 ℃, 120 ℃, 140 ℃
After leaving each for 5 minutes in the atmosphere, a peeling test was performed to obtain a value of adhesive strength. The adhesive strength value is the average value of 5 test pieces (maximum, minimum 2 point cut), and the thermal creep resistance is the average value of 3 test pieces.

The results of carrying out the adhesion test on various substrates are shown below. The workability of the adhesion test was very good.

[0041]

[Table 1] * GFPP: Glass fiber reinforced polypropylene plate * GFP: Glass fiber reinforced phenolic resin plate

[0042]

[Table 2]

As is clear from the above examples, since these multilayer laminates can be manufactured very easily and hygienically, and have excellent adhesive strength at room temperature and heat-resistant creep at high temperature, they are laminated materials, especially It can be widely used as a laminated material for automobile interiors. In addition, when the temperature is higher than 140 ° C, the adhesive strength is remarkably reduced.
It is very suitable for sorting and recycling for each laminated member.

Example 2 Instead of using polypropylene in Example 1, a linear polyethylene resin, Syolex 108FF-1 (MF, manufactured by Showa Denko KK) was used.
R (190 ° C.) = 1.0, density = 0.920 g / cc,
70% by weight of melting point (DSC method) = 120 ° C.) was used.
That is, the ratio of the copolymer and the linear polyethylene is 30/70.
To produce a resin composition. When the same evaluation as in Example 1 was performed, the workability was very good, and the following values were also obtained for the adhesive strength and the heat-resistant creep.

[0045]

[Table 3]

[0046]

[Table 4]

These multi-layer laminates are very widely used as laminate materials, especially interior materials for automobiles, because they can be manufactured very easily and hygienically and have excellent adhesive strength at room temperature and excellent heat-resistant creep at high temperatures. it can. Also, 140 ℃
When the temperature was raised to a higher temperature, the adhesive strength was remarkably reduced, and therefore, it is very suitable for peeling a defective molded product and separating and recycling each laminated member.

Example 3 In Example 1, an ethylene-n-butyl acrylate-maleic anhydride terpolymer was used as the ethylene-based copolymer. The copolymer was produced under the conditions of a polymerization temperature of 240 ° C. and a polymerization pressure of 1900 Kg / cm ² using equipment of a high-pressure low-density polyethylene plant. The MFR of the copolymer was 10, the content of units derived from n-butyl acrylate was 12% by weight, and the unit derived from maleic anhydride was 1.8% by weight. The composition of the comonomer was determined by infrared absorption spectrum. The same experiment as in Example 1 was conducted using this copolymer. The workability was very good, and the following values were also obtained with respect to adhesive strength and heat-resistant creep.

[0049]

[Table 5]

[0050]

[Table 6]

These multi-layer laminates can be widely used as a laminate material, particularly as an automobile interior material, because the production work can be carried out very easily and hygienically, and the adhesive strength at room temperature and the heat-resistant creep at high temperature are excellent.

(Comparative Example 1) In Example 1, only the copolymer was used without using polypropylene. The following values were obtained for adhesive strength and heat-resistant creep.

[0053]

[Table 7] Although the adhesive strength was relatively good, the heat-resistant creep property was significantly lowered, and there was a great problem in using it as a laminate material, particularly as a laminate material for automobile interiors.

(Comparative Example 2) In the copolymer of Example 1, maleic anhydride was not used, but an ethylene-methyl methacrylate binary copolymer was used. Before the measurement of heat-resistant creep, the adhesive strength was completely insufficient, and a multilayer structure that could withstand practical use could not be obtained.

[0055]

EFFECT OF THE INVENTION The multilayer structure according to the present invention is very easy to manufacture and has excellent adhesive strength at room temperature and high temperature, so that it can be suitably used as a laminated material, particularly as an interior material for automobiles.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical indication location (C08L 23/08 23:06 7107-4J 23:14) 7107-4J (72) Inventor Katsuaki Tsutsumi Oita-shi, Oita 2 Nakanosu, Showa Denko Stock Company Oita factory

Claims (5)

[Claims] 1. A multilayer structure comprising at least a skin material, a thermoplastic resin and a substrate material, wherein the thermoplastic resin is a polyolefin resin composition comprising the following (1) and (2): And laminated material. (1) A multi-component copolymer composed of ethylene, a radical polymer acid anhydride, and a radical-polymerizable comonomer other than this, 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 or less, and the ratio of units derived from other radical polymer comonomer is 3% by weight
10 to 50% by weight of the above ethylene-based copolymer
90% by weight and (2) a polyolefin resin 90 having a melting point of 100 ° C. or higher.
-10% by weight 2. The laminated material according to claim 1, wherein the polyolefin resin having a melting point of 100 ° C. or higher is selected from polypropylene and polyethylene. 3. A linear low-density polyethylene in which a polyolefin resin having a melting point of 100 ° C. or higher uses a comonomer selected from propylene, butene-1,4-methylpentene-1, hexene-1, and octene-1, and The laminated material according to claim 1 or 2, which is a propylene-based copolymer using a comonomer selected from ethylene, butene-1, 4-methylpentene-1, hexene-1, and octene-1. 4. The melting point of the linear low-density polyethylene or propylene copolymer is 120 to 150 ° C., and 140
A thermoplastic resin which has an adhesive strength at a high temperature of ℃ or higher of 1/3 or less of the adhesive strength at 120 ℃.
3. The laminated material according to item 3. 5. The laminated material according to claim 1, wherein the laminated material is an automobile interior material.