JPH0729400B2 - Sheet material for vehicle interior material molding - Google Patents

Description

TECHNICAL FIELD The present invention relates to a sheet material for forming a vehicle interior material, which is excellent in adhesiveness, feel and touch, and has flame retardancy.

[Prior Art] Vehicles, particularly automobile interior materials such as seats, door trims, ceiling materials, and floor carpets generally have a base material (hereinafter, abbreviated as a skeleton base material) that forms a basic shape and a skin base material that covers the base material. And / or a backing substrate. Conventionally, solvent-based adhesives have been used for adhesion between these base materials, but in recent years, the adhered base materials are stacked via a hot-melt resin film, web, or powder, and heated and pressed. A method of melting a hot-melt resin and molding an intended interior material has been proposed.

In molding processing of interior materials using a conventional solvent-based adhesive, for example, a urethane-based solution-based adhesive, the urethane-based adhesive is applied to one of the bonding surfaces of the skeleton base material, the skin base material and / or the backing base material. Is applied, the solvent is evaporated, the substrate to be adhered is pasted, and it is further heated and cured, resulting in poor productivity, and the work environment is contaminated by the solvent that evaporates and is discharged from the factory. There was a problem such as air pollution around the factory.

Although the recently proposed method using hot-melt adhesive solves the above-mentioned problems in using solvent-based adhesives considerably, it improves productivity, responds to diversification of substrates to be adhered, and stabilizes product quality. The problem still remains in that respect.

In Japanese Utility Model Publication No. 52-133432, in molding an automobile carpet, a thermoplastic resin film is superposed between a pad hill and a carpet, and then the thermoplastic resin film is melted by applying pressure and heat. And Pat Hill are proposed to be adhesively molded.

Further, in JP-A-56-118816, in molding a ceiling material, a thermoplastic powder adhesive is applied onto a thermoplastic synthetic resin sheet, and when the sheet is heat-molded into a predetermined shape, powder bonding is performed. It is proposed that the agents are melted at the same time, and then the skin base materials are superposed and cold-pressed and bonded.

[Problems to be Solved by the Invention] In the method disclosed in Japanese Utility Model Laid-Open No. 52-133432, a thermoplastic resin film is inserted between adherend substrates and adhered at a temperature equal to or higher than the melting point of the film. Since heat and pressure are applied from both sides of the base material, there are problems that the base material to be adhered is thermally deformed, adhesion is displaced, and wrinkles or floats occur.

Further, in the method disclosed in the above-mentioned JP-A-56-118816, equipment for uniformly coating the powdery adhesive on the thermoplastic synthetic resin sheet, measures for preventing powder scattering are required, Further, there is a problem that spots of adhesion of the powdery adhesive and spots of particle size of the powdery adhesive cause adhesion unevenness or floating.

In recent years, there has been a strong tendency to demand comfort and livability in automobile interiors. Therefore, a skin material used for the interior material is required to have a good feel and touch, and a deep-drawn polyvinyl chloride leather, a fiber-raised cloth, a natural leather, an artificial leather, etc. have come to be used. On the other hand, as the skeleton base material, cushioning materials such as soft polyurethane foam, polyethylene foam, and polypropylene foam have come to be used together with paper boards and synthetic resin boards. The emergence of hot melt adhesives that can respond to the diversification of these adhered substrates is expected.
Conventionally, ethylene-vinyl acetate copolymer (so-called EVA) hot melt adhesives and polyamide hot melt adhesives have been widely used in the field, but these hot melt adhesives are made of polyvinyl chloride, polyethylene terephthalate fiber cloth. Adhesiveness with is poor, which is a big limitation in use.

Further, from the viewpoint of preventing in-vehicle fires from cigarettes, lighters, matches, etc., automobile interior materials are also required to have flame retardancy, for example, passing the MVSS-302 standard in the United States. Along with making the interior material forming base material flame-retardant, making the hot-melt adhesive itself flame-retardant is also a serious problem.

[Means and Actions for Solving Problems] As a result of intensive studies by the present inventors for solving the above problems,
The present invention has been completed by discovering that it is effective to superpose a substrate on which a hot-melt resin composition imparted with flame retardancy is laminated in advance and melt-bond the substrates.

An object of the present invention is to provide a sheet material for forming a vehicle interior material, which has good adhesion to various base materials, has a good feel and feel after adhesion, is excellent in heat resistance, and has flame retardancy. is there. Further, the object is to provide a sheet-shaped base material which allows easy work of superposing adhered base materials, enables uniform adhesion, and achieves improvement in product quality and productivity.

According to the present invention, there is provided a vehicle interior material molding sheet material in which a hot-melt resin composition is laminated on at least one surface of a substrate, wherein the hot-melt resin composition comprises terephthalic acid units of 30 to 55 mol% and isophthalic acid units. 5 to 40%, at least one saturated dicarboxylic acid unit selected from fatty acid dicarboxylic acids having 4 to 12 carbon atoms and at least one kind of dicarboxylic acid consisting of 10 to 60 mol% and alkylene glycol having 2 to 10 carbon atoms It is composed of glycol mainly
A sheet material for vehicle interior material molding, comprising 100 parts by weight of a polyester hot melt resin having a softening point of 90 to 160 ° C. and a Shore D of 50 or less, and 5 to 30 parts by weight of a halogen flame retardant. It

The term "base material" as used in the present invention refers to a base material that constitutes an interior material of a vehicle, that is, a base material that is in the form of an inner sheet of a skeleton base material, a skin base material and a backing base material. As the skeleton base material, for example, a soft polyurethane foam in a seat, a paper board in a door trim, a synthetic resin board such as polyethylene and polypropylene, a paper board in a ceiling material, polystyrene, a synthetic resin board such as a modified polystyrene containing rubber, or If necessary, the board may be used in combination with a cushion material such as a soft polyurethane foam or a polyethylene foam. Examples of the skin base material include soft polyvinyl chloride leather, polyethylene terephthalate, nylon 6, nylon 66, polyacrylonitrile, fiber-raised cloth such as cotton, natural leather, artificial leather, and the like. As the backing base material, cotton, Examples thereof include vinylon, polyethylene terephthalate, nylon 6, nylon 66 fiber cloth, soft polyvinyl chloride sheet, synthetic rubber sheet and the like.

The term "aliphatic dicarboxylic acid having 4 to 12 carbon atoms" as used in the present invention means, for example, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, 1,10-decanedicarboxylic acid, and the like. What is alkylene glycol of 10?
For example, ethylene glycol, 1,4-butanediol, 1,6
-Hexanediol, neopentyl glycol, 1,2-
Propanediol, 1,3-propanediol and 1,5-pentanediol.

The polyester-based hot-melt resin used in the present invention has a thermal deformation temperature of the adherend substrate, a heat resistance required as an interior material, and a texture and a touch of the interior material surface.
A polyester having a softening point of 90 to 160 ° C. by a ring and ball method and a resin hardness of Shore D of 50 or less. If the softening point is less than 90 ° C, the heat resistance required for interior materials cannot be withstood. Softening point
If it exceeds 160 ° C., the temperature at the time of melt-adhesion becomes high, causing thermal deformation or thermal deterioration of the adherend substrate, for example, soft vinyl chloride leather, polyurethane foam, etc., impairing the surface appearance of the obtained interior material. When the resin hardness exceeds 50 in Shore D, the surface layer of the obtained interior material becomes hard and the feel and touch are impaired.

The halogen-based flame retardant in the present invention, for example, aromatic halogen compounds such as decabromodiphenyl ether, hexabromodiphenyl ether, decabromodiphenyl,
Halogenated polycarbonate such as brominated polycarbonate obtained from tetrabrominated bisphenol A and phosgene,
Halogenated copolymerized polycarbonate obtained from tetrabrominated bisphenol A and phosgene, halogenated epoxy compound obtained from tetrabrominated bisphenol A and epichlorohydrin, brominated polystyrene, brominated polyphenylene oxide, brominated benzyl alcohol and acrylic ester Examples thereof include a brominated polymer, a condensation polymer obtained from isocyanuric acid and halogenated bisphenol A.

The content of the halogen-based flame retardant in the present invention is preferably 5 to 30 parts by weight with respect to 100 parts by weight of the polyester. If the amount of the halogen-based flame retardant compounded is less than 5 parts by weight, the desired flame retardant effect cannot be obtained, and if it exceeds 30 parts by weight, the flame retardant effect is conspicuous, but the properties as a hot melt adhesive Change and the adhesive performance is impaired.

In the present invention, an oxide of a Group V metal of the periodic table may be added to further enhance the flame retardant effect. Examples of the metal oxide include antimony oxide, bismuth oxide, lead oxide and the like, and antimony oxide is particularly preferable. When these metal oxides are used, the blending amount thereof is preferably 3 to 15 parts by weight with respect to 100 parts by weight of the polyester.

If necessary, the polyester hot melt resin composition of the present invention may contain other thermoplastic resins, various additives, stabilizers and the like. There is no particular method for obtaining the resin composition.

The method for laminating the polyester hot melt resin composition of the present invention on a substrate is not particularly limited, and for example, an extrusion coater or a roll coater can be used. The laminate thickness of the hot melt resin composition varies depending on the purpose of use, but it is usually desirable to set it to 20 μm or more in order to provide sufficient adhesive strength. Lamination to the base material may be performed on both the adhering surfaces of both base materials to be adhered, or may be laminated on only one base material.
Further, the skeleton base material which is an intermediate material of the interior material may be laminated on both front and back surfaces, or when the mating base material is laminated, the laminating of the surface to be bonded to the mating base material surface may be omitted. Good.

The sheet material obtained as described above is overlaid with the mating base material, heated to a temperature necessary for melting the hot melt resin composition, and exhibits good adhesion just by pressurizing, and a desired interior material. You can get it.

[Examples] Next, the content of the present invention will be specifically described with reference to Examples.

First, in showing an example, the measuring method of each measured value shown in the example will be briefly described below.

Softening point: Measured according to JIS K 2207 (ring and ball method).

Shore D: Measured according to ASTM D 2240.

180 degree peel adhesion strength: Autograph PM-1 manufactured by Shimadzu
00 was used at a tensile speed of 200 mm / min at room temperature (25 ° C) and 80 ° C atmosphere.

Flame retardance evaluation: The burning rate was measured according to the MVSS-302 standard.

Example 1 and Comparative Examples 1 and 2 (Synthesis of Resin) 155 parts by weight of dimethyl terephthalate (hereinafter abbreviated as 0.79)
Mol), 295 parts of 1.4-butanediol (3.28 mol) and 0.22 parts of tetraisopropyl titanate as catalyst (0.008 mol).
(07 mol) was added, and the mixture was heated to 180 to 220 ° C. under a nitrogen stream in a reaction vessel to completely distill off methanol while refluxing 1,4-butanediol to carry out a transesterification reaction. Next, 66 parts of isophthalic acid (0.40 mol) and 117 parts of adipic acid (0.80 mol) were added, and water was distilled out of the system while refluxing 1,4-butanediol at 220 ° C. for 2 hours to carry out an esterification reaction. After that, the temperature was raised from 220 ° C to 240 ° C over 1 hour, and in parallel with this, the pressure was gradually reduced to 0.5 mmHg. Then, polycondensation was performed for 3 hours under the conditions of 240 ° C. and 0.5 mmHg to obtain polyester A. The softening point of this polymer was 120 ° C., and Shore D was 40.

Next, the acid component composition and the type of glycol component were changed, and the other conditions were the same as above to produce a polyester. The composition, softening point and Shore D of this polyester are shown in Table 1.

Example 2 and Comparative Examples 3 and 4 100 parts by weight of the polyester A obtained in Example 1 was used in an amount of decabromodiphenyl (manufactured by Mitsui Toatsu Chemical Co., Inc., trade name: Planeteron), brominated polystyrene ( Nissan Fellow Organic Chemical Company, product name: Pyrocheck 68PB)
And, if necessary, antimony trioxide was added and melt-mixed at 150 ° C. using a 50 m / mφ extruder. Using a hot-melt roll coater manufactured by Matsushita Industrial Co., Ltd., the resulting hot-melt resin composition was applied onto a vinylon base cloth (thickness: about 0.2 mm) to give a thickness of 100.
It was laminated by μm. Two sheets of the laminated base cloth are laminated so that the laminated surfaces are in contact with each other, and at 150 ° C for 40 seconds, 0.5 kg.
An adhesive sample was obtained by heating and pressurizing at f / cm ² , and 180-degree peel adhesive strength and flame retardancy were evaluated. The results are shown in Table 2.

Example 3 100 parts by weight of the polyesters obtained in Example 1 and Comparative Examples 1 and 2 were melt mixed with 20 parts by weight of decabromodiphenyl ether. These hot melt resin compositions were laminated in the same manner as in Example 2 on the back surface of a soft polyvinyl chloride leather (thickness of about 1 mm) having a satin-finished surface unevenness to a thickness of 100 μm. The laminated leather was overlaid on a paper board (thickness: 3 mm), and the adhesion temperature at which the adherend substrate was destroyed was investigated by a 180 degree peel adhesion strength test at 25 ° C (however, the heating time was
40 seconds, the load is constant at 0.5 kgf / cm ^2. )

Further, the surface condition of the soft polyvinyl chloride leather of the test piece adhered under the conditions was observed. As a result, polyester A,
Hot-melt resin composition using B, C, D is about 1 from the softening point
Sufficient adhesion was developed at a temperature as high as 0 ° C., and the surface of the vinyl chloride leather had a satin pattern similar to that before adhesion. The hot melt resin composition used in Comparative Example 1 required heating at about 180 ° C., and the satin pattern was considerably eliminated. The hot-melt resin composition of Comparative Example 2 has a softening point of 75 ° C., which is lower than 90 ° C. which is required for automobile interior materials, and cannot be used as an automobile interior material because of insufficient heat resistance.

[Effects of the Invention] As is clear from the practice of the present invention, the sheet-shaped substrate of the present invention is easy to carry out the bonding operation, and has excellent texture and feel after bonding,
Moreover, since it is provided with flame retardancy, it can be effectively used as a molding material for automobile interior materials.

Claims (1)

[Claims] 1. A sheet material for forming a vehicle interior material, comprising a hot melt resin composition laminated on at least one side of a substrate, wherein the hot melt resin composition comprises terephthalic acid units 30.
To 55 mol%, 5 to 40 mol% of isophthalic acid unit, and 10 to 60 mol% of at least one saturated dicarboxylic acid unit selected from fatty acid dicarboxylic acid having 4 to 12 carbon atoms and a dicarboxylic acid having 2 carbon atoms. Is composed of at least one glycol of alkylene glycol of ~ 10,
100 parts by weight of a polyester-based hot melt resin having a softening point of 90 to 160 ° C and a Shore D of 50 or less, a halogen-based flame retardant 5
A sheet material for forming a vehicle interior material, which is characterized by comprising 30 to 30 parts by weight.