JP3110290B2 - Non-breathable hot melt film and interior materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-breathable hot-melt film and an interior material having the film interposed therebetween, particularly an automobile interior material.

[0002]

2. Description of the Related Art As an interior material for automobiles and indoors, a material in which a skin material and a base material are bonded via a hot melt film is used. In particular, various ideas have been devised for automotive interior materials from the viewpoints of weight reduction, heat insulation, non-breathability and the like.

As the hot melt film, there have been proposed many uses of a multilayer hot melt film in which both sides of a non-breathable film are sandwiched with a hot melt adhesive film in order to prevent air permeability in a sectional direction.

On the other hand, as a skin material disposed inside an automobile, a material in which a cushion layer (3) such as a foamed soft polyurethane is provided on a woven fabric, a knitted fabric, a brushed knit, artificial leather, or the like is used. When the cushion layer (3) is thermocompression-bonded to a base material through a conventional hot-melt film having a three-layer structure, when the melting point of the hot-melt resin layer is low, dents (commonly known as avatars) often occur on the surface of the skin material. .

Japanese Patent Application Laid-Open No. 7-60883 discloses a non-breathable hot-melt film having a two-layer structure. This film uses a heat-resistant resin layer (non-breathable resin layer) on the substrate side. It cannot be used when the substrate is a resin board or cardboard.

[0006]

DISCLOSURE OF THE INVENTION The present invention relates to an automobile having a structure in which a cushion material such as a foamed soft polyurethane is backed on the back surface of a skin material such as a knitted fabric, and this is fused to a substrate with a non-breathable hot melt film. In the interior materials of
It is an object of the present invention to provide a non-breathable hot melt film suitable for suppressing frequent pricking of the surface of a skin material and an interior material fused through the film.

[0007]

The present invention relates to an interior material having a skin material (4), a cushion layer (3), a non-breathable hot melt film (5) and a substrate (6) in this order, At least a non-breathable resin layer (1) made of a thermoplastic resin film having a melting point of 130 to 250 ° C. and a hot-melt resin layer (2) bonded to a substrate, wherein the non-breathable hot melt film is bonded to the cushion layer. The present invention relates to an interior material comprising two layers, wherein the thickness of the air-impermeable resin layer is 5 to 30 μm and the total thickness of the air-impermeable hot melt film is 20 to 80 μm. More specifically, the present invention relates to the interior material, wherein the hot melt resin layer has a melting point of 70 to 130 ° C and a melt flow index (MI) of 3 to 100.

The resin for the air-impermeable resin layer (1) used in the present invention has a melting point of 130 ° C. or higher, preferably a melting point of 130 to 250.
C., more preferably 140-230.degree. C., a resin higher than the molding temperature, preferably 20.degree. C. or higher, and desirably a resin that can be fused with a foam laminate of polyurethane foam.

Preferred examples of the resin include a high melting point polyamide resin, a high melting point polyolefin resin, a polyester resin, a polyurethane resin, an acrylic resin, a polycarbonate resin and the like.

High melting point polyamide resins include nylon 6/66, 6, 6/10, 12, and 11; high melting point polyolefins include polypropylene resins and ethylene-
A vinyl alcohol copolymer is exemplified.

The basic structure of the non-breathable hot melt film of the present invention is shown in FIG. 1, and the basic structure of the interior material is shown in FIG.

FIG. 1 is a schematic cross-sectional view of a non-breathable hot-melt film, in which (1) is a non-breathable resin layer, (2) is a hot-melt resin layer, and FIG. 2 is a schematic cross-section of an interior material. Figure,
(3) is a cushion layer, (4) is a skin material, (5) is a non-breathable hot melt film, and (6) is a base material.

The non-breathable resin layer (1) is used to block the breathability between the base material and the skin material and to prevent the surface of the skin material from being stained by ventilation. It is desirable that no mechanical damage or pinholes be formed. Therefore, the thickness is 5 μm or more, more preferably 10 μm.
３０30 μm is suitable. When the thickness is 30 μm or more, the elongation becomes poor, and the stretchability of the drawn portion becomes poor during thermal fusion with the substrate.

The hot melt resin layer (2) is used to fuse the substrate (6) and the air-impermeable resin layer (1). Therefore, the melting temperature of the hot melt resin is 70 to 150 ° C., particularly 80 ° C.
A temperature of about 130 ° C. is preferable. In particular, when a material to be subjected to low-temperature thermocompression bonding such as a cardboard or resin board is used as the base material, a temperature lower than the thermocompression bonding temperature, for example, 70 to 1
It is preferable to use a resin having a melting point of 30 ° C. In the case of such low-temperature thermocompression bonding, the melt viscosity of the hot-melt resin at a low temperature is usually high, so that it is difficult to achieve the permeability to the cardboard or resin board as the base material. Therefore, a resin having an extremely small MI is not suitable as the resin used. Preferred MI is 5-100, more preferably 6-5
0.

The thickness of the hot melt resin layer (2) is 10 to 5
0 μm, more preferably 20 to 40 μm.

Resins suitable for the hot melt resin layer (2) are polyolefin resins, low melting polyamide resins, polyester resins, thermoplastic polyurethane resins and the like. Polyolefin resins are cost-effective.

Examples of the polyolefin resin include polyethylene, for example, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, branched low-density polyethylene, and the like, polypropylene, modified polypropylene, 1-butene, 2-butene, Isobutene,
1,3-butadiene and the like; olefin monomer copolymer,
Copolymers with other monomers having a polymerizable double bond such as styrene and vinyl chloride; ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-butyl acrylate Copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-butyl methacrylate copolymer, ethylene-
Examples thereof include (meth) acrylic acid copolymers, ethylene-maleic acid copolymers, ethylene-itaconic acid copolymers, and modified resins such as acid modifications thereof.

These polyolefins may be used as a mixture of two or more. Other additives such as a viscosity modifier, a tackifier, and an antioxidant may be added. Olefin homopolymers, for example, polyethylene homopolymers, when used alone, have poor fusion properties with substrates such as cardboard, resin boards or thermoformable polyurethanes, so other polyethylene resins such as ethylene-vinyl acetate, ethylene-ethyl acrylate , Ethylene- (meth) acrylic acid, ethylene-maleic acid copolymer, acid-modified olefin resin, and the like.

As polyamides, nylon 6/66 /
12, nylon 6/610/12, nylon 6/66 /
610/12, nylon 6/66/11/12 and the like. In terms of adhesiveness, an aminocarboxylic acid made from ω-aminoundecanoic acid or the like is used as at least one monomer.
Those containing as a component are preferred.

When the base material is cardboard, resin board, etc., particularly preferred hot melt resins are ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-butyl acrylate copolymer. Coalesce, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-butyl methacrylate copolymer,
Ethylene- (meth) acrylic acid copolymer, ethylene-maleic acid copolymer, ethylene-itaconic acid copolymer, modified resin such as acid modification thereof, acid-modified resin of polyethylene or a mixture of these and polyethylene It is a modified polyethylene resin.

The air-impermeable hot melt film of the present invention has a three-layer structure in which another resin layer is provided between the air-impermeable resin layer (1) and the hot-melt resin layer (2) in addition to the above two-layer structure. The above multilayer structure may be adopted. Such a resin layer is mainly
An adhesive layer for bonding the layers (1) and (2), an intermediate layer for blending in the case where the fusing properties of the two are insufficient, or a hot melt resin layer (2) that is melted together. It is used to develop various functions such as a layer for adjusting fluidity.

In the present invention, the method for producing a non-breathable hot melt film is not particularly limited, and any method generally used for producing a laminated film, such as a coextrusion method, an extrusion lamination method, and a dry lamination method, may be used. It is not particularly limited.

The total thickness of the multilayer hot melt film is from 20 to
It is good to adjust to 80 μm, more preferably 30 to 70 μm.

In the present invention, the interior material has a cushion material (3) such as foamed flexible polyurethane on the back side of the skin material. Conventionally, this cushion material and the air-impermeable resin layer (1) have been fused through a hot melt film.
This has often been found to cause skin popping. In the present invention, the air-impermeable film is adhered to the foamed flexible polyurethane layer by a frame laminating method, a dry laminating method or the like without interposing the hot melt film, thereby eliminating the pock.

As such a skin material, a non-woven fabric generally used as an interior material, for example, a polyester non-woven fabric;
There are woven, knitted and brushed knit. The thickness of the skin material is preferably 1 to 3 mm.

The cushion material used in the present invention is a flexible polyurethane foam, and is bonded to a non-breathable film by a method such as frame lamination, dry lamination or hot melt lamination.

The density is preferably 0.016 to 0.050 g / cm ₃ , more preferably 0.020 to 0.035 g / cm ³ . The thickness of the cushion material is 1 to 10 mm, more preferably 2 to 5 m
m. If the thickness is less than 1 mm, it is difficult to join by frame lamination or the like. If the thickness is more than 10 mm, lateral ventilation is generated and the skin material is easily stained. It also becomes expensive. If the thickness of the cushion material is thin, the softness of the interior material is lost, and the interior material becomes flat.

As the substrate of the present invention, those used as conventional substrates for automobile interiors may be appropriately used. Examples of such a base material include a nonwoven fabric in which inorganic fibers, organic fibers or a mixed fiber thereof are bonded to each other with a thermoplastic resin, or a molded article of organic fibers or inorganic fibers impregnated with a thermosetting resin. There are a substrate, cardboard and the like in which a glass fiber layer or the like is bonded to both sides of a resin foam such as a board or urethane. After the step of heat-forming (shaping) a cardboard, a resin board and the like by a hot press, it is thermocompression-bonded to a skin material in the next step. Usually, a hot press is used for the thermocompression bonding, and the temperature is set at 110 to avoid damaging the skin material.
Heat fusion at low temperature of ~ 130 ° C. As described above, when the thermocompression bonding temperature is low, if the MI of the hot melt film is small, the melting temperature becomes high, and the hot melt film does not penetrate into the base material, so that sufficient fusion strength cannot be obtained. Therefore, when such a material is used, it is preferable to use a resin having high fluidity at a low temperature, particularly MI5 or more, as the hot melt resin layer (2).

The method of manufacturing the interior material of the present invention is as follows. First, the air-impermeable resin layer (1) of the obtained air-impermeable hot melt film is adhered to the foamed flexible polyurethane side of the skin material backed with the foamed polyurethane. Hot melt resin layer (2)
Is thermally fused to the substrate (6). The conditions for hot pressing are as follows: press mold temperature 110-140 ° C clearance 0.3-1.5 mm time 10-60 seconds

Hereinafter, the present invention will be described with reference to examples.

The air-impermeable hot melt film shown in FIG. 1 in EXAMPLE 1 The following configuration was produced by co-extrusion (T die method). Non-breathable resin layer (1): Copolymer nylon 6/66, melting point 200 ° C., thickness 15 μm Hot melt resin layer (2): Copolyamide, 6/610/12, melting point 105 ° C., MI12, thickness 30 μm Overall thickness 45 μm

Example 2 A non-breathable hot melt film was produced by a co-extrusion blow-molding method according to the following formulation. Non-breathable resin layer (1): Copolymer nylon 6/66, melting point 200 ° C., thickness 15 μm, hot melt resin layer (2): ethylene-acrylic acid copolymer resin, melting point 95 ° C., MI 8.0, thickness 30 μm

Example 3 Non-breathable resin layer (nylon 6, melting point 220 ° C., thickness 20)
μm, cast film) and a hot melt resin layer (eletin-ethyl acrylate copolymer resin, melting point 90 ° C., MI
20) was extruded at a thickness of 30 μm and laminated to obtain a two-layer film having a thickness of 50 μm.

Example 4 A skin material comprising a knitted (tricot) polyester fiber,
Foamed soft polyurethane cushion material and Examples 1 to
The non-breathable hot melt film obtained in 3 is bonded with the non-breathable resin layer (1) to the cushion material (3) side, and the non-breathable resin layer is bonded by a frame laminating method of the cushion material. I got Next, the hot-melt resin layer (2) of the obtained skin laminate is placed on a resin board substrate (thickness: 3 mm) with the substrate (6) facing, and bonded by hot pressing under the following conditions to produce interior materials. did.

Upper press temperature: 120 ° C., lower press temperature: 160 ° C. Clearance: 0.5 mm, time 30 seconds

Comparative Example Same as Example 1 except that the polyamide 6 / 6-10 / 12 (melting point 105 ° C., MI12 and thickness 30 μm) was provided on both sides of the air-impermeable resin layer (1) of Example 1. Thus, a hot melt film having a three-layer structure and having an air-impermeable resin layer (1) in the middle was obtained. This was obtained in the same manner as in Example 4 to obtain a skin laminate, and then laminated with a resin board to produce an interior material. The peeling test, the heat-resistant creep test, and the pinhole test of the non-breathable hot melt film of the obtained interior material and skin laminate material were performed by the following methods. Table-Results
It is shown in FIG.

Test Method (1) Peeling Test The skin laminate and the interior material were cut to a width of 25 mm, and the adhesive strength was measured with an Instron type tensile tester. Conditions Laminated skin material T peeling, 23 ° C, tensile speed 200mm / min Interior material 180 ° peeling, 23 ° C, tensile speed 200mm / min (2) Pinhole test With hot melt resin layer surface of laminated skin material and cushion material of interior material A commercially available pinhole detection solution (Nippon Kozai Co., Ltd., Microcheck) on the non-breathable resin surface from which the skin material has been removed
And left for 1 minute to wipe off the liquid and to examine for pinholes. (3) Heat-resistant creep test The interior material was cut to a width of 25 mm, the skin material with the cushion layer was peeled off from the base material, and a load of 100 g was applied to the skin material with the cushion layer while maintaining the 180 ° peeled state. For 24 hours, and the degree of peeling was examined.

[0037]

[Table 1]

[0038]

The non-breathable hot melt film of the present invention can be easily fused to a cushioning material such as foamed soft polyurethane by a method such as frame lamination, and has excellent heat adhesion to a base material. The interior material obtained by using it hardly generates pock on the skin surface despite the interposition of the cushion material.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a non-breathable hot melt film.

FIG. 2 is a schematic sectional view of an interior material.

[Explanation of symbols]

 (1) Non-breathable resin layer (2) Hot melt resin layer (3) Cushion layer (4) Skin material (5) Non-breathable hot melt film (6) Base material

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-9-39177 (JP, A) JP-A-7-68721 (JP, A) JP-A-7-186844 (JP, A) 162225 (JP, A) JP-A-9-52312 (JP, A) JP-A 1-145649 (JP, U) JP-A 61-113158 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 1/00-35/00

Claims (2)

(57) [Claims] An interior material having a skin material (4), a cushion layer (3), a non-breathable hot melt film (5) and a base material (6) in this order, wherein the non-breathable hot melt film comprises: Melting point 130-2 bonded to cushion layer
It is composed of at least two layers of a non-breathable resin layer (1) made of a thermoplastic resin film at 50 ° C. and a hot-melt resin layer (2) bonded to a base material, and the thickness of the non-breathable resin layer is 5 to 5.
An interior material having a thickness of 30 μm and a total thickness of a non-breathable hot melt film of 20 to 80 μm. 2. The hot melt resin layer has a melting point of 70 to 130.
° C and a melt flow index (MI) of 3 to 10
The interior material according to claim 1, which is 0.