JPH0596696A - Method for forming outer film on thermoplastic resin base material - Google Patents

Abstract

PURPOSE:To reduce impairment to base material and outer film and obtain a sufficient adhesive strength therebetween in laminating the outer film on the aforesaid base material made from a thermoplastic resin and shaped into a required form. CONSTITUTION:A method for forming the outer film comprises a process a2 wherein a thermoplastic resin base material is softened by heating so as to be pressure formed, a process (b) wherein hot melt is applied to the joint faces of the shaped base material and the outer film material to be laminated thereon and a process c1 wherein the base material and the outer film material are both heated, joined together at the hot melt applied faces and pressed together with a higher pressure than that applied upon shaping the base material to bond together the base material and the outer film material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for laminating a skin material on a thermoplastic resin base material formed into a desired shape, and particularly, while the suitable forming temperature of the base material is relatively high,
The present invention relates to a method for laminating a skin on a thermoplastic resin base material having a suitable skin material adhesion temperature of a relatively low temperature.

[0002]

2. Description of the Related Art Laminates in which a skin material such as a fabric is laminated on a thermoplastic resin substrate have been used for automobile interior materials and the like because they can be obtained by a simple construction method and are lightweight and low in cost.

This type of thermoplastic resin base material is heated until the thermoplastic resin forming the base material is softened so that the base material can be shaped, and a predetermined clearance approximately equal to the base material thickness is provided. It is arranged between the molding dies that have it and is pressed and shaped.

Further, a method of laminating and adhering an epidermis to a thermoplastic resin base material of this kind is a film-like or web-like low melting point thermoplastic resin material, so-called hot melt, on the adhering surface of the base material or the epidermis material. It is applied in a temporarily fixed state, and the base material and / or skin material is heated until the applied hot melt material is softened, and then the hot melt applied surface of the base material or skin material is faced and pressed repeatedly to adhere the skin material. To do.

The shaping order of the base material and the sticking order of the skin material are based on the so-called thermoplastic resin base material in which the suitable shaping temperature of the base material is lower than or substantially equal to the melting point of the hot melt of about 100 to 110 ° C. Adhere the skin material at the same time as shaping the material or stick the skin material prior to shaping the base material, and the shaping temperature of the base material is higher than the melting point of the hot melt, so-called thermosetting resin base material It is common to shape the substrate first and then apply the skin material later.

However, a certain type of thermoplastic resin base material, particularly a base material containing glass fiber in a thermoplastic resin which has been frequently used these days, has a forming temperature even though the constituent resin of the base material is the thermoplastic resin. If the temperature is not much higher than the melting point of the hot melt, the base material may not be sufficiently softened and suitable shaping may not be possible.

In the case of such a base material, as in the case of the thermosetting resin base material, the method of sticking the epidermis after shaping the base material is used, but the temperature at the time of sticking the skin material and the shaping temperature of the base material are There is a problem that it is difficult to achieve balance, sufficient adhesive strength of the epidermis cannot be obtained, and the epidermis peels off, or the base material cannot withstand the pressure applied when the epidermis is attached and the base material is crushed and the shaped shape is damaged.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a preferable skin material bonding temperature is a relatively low temperature while a suitable shaping temperature of a substrate is a relatively high temperature. A skin laminating method suitable for a certain thermoplastic resin substrate, particularly for a glass fiber-containing thermoplastic resin substrate.

[0009]

[Means for Solving the Problems] Means of the present invention for solving the problems comprises a step of laminating a skin on a thermoplastic resin substrate by heating the thermoplastic resin substrate to soften it and press-forming it. A step of applying a film-shaped or web-shaped hot melt to each laminated surface of the shaped base material and the skin material to be laminated thereon, and heating the shaped base material and the skin material, respectively, to provide a hot melt application surface. By facing each other and stacking the base material and the skin material by laminating and pressing the base material with a pressure larger than the pressure applied when shaping the base material.

In the step of applying hot melt to both the thermoplastic resin base material and the skin material which have been shaped by the skin laminating method of the present invention and heating them respectively, both the base material and the skin material before lamination are laminated. The hot melt is in a well-adapted state, and the hot melt-applied surfaces are faced to each other and stacked, and the surface is pressed with a pressure that is larger than when the base material is shaped, so the hot melt presses between the base material and the skin material. By being spread, the gap between the base material and the skin material can be filled without any gap, and good adhesion can be achieved.

[0011]

The preferred embodiments of the present invention will be described below with reference to the drawings, but the contents of the invention are not limited thereto.

FIG. 1 is a cross-sectional view of a laminated material in which a skin material 1 is laminated and adhered to a thermoplastic resin base material 2 which is the object of the present invention. The base material and the skin material are hot melt 3b provided on the base material side, And, they are laminated and attached via the hot melt 3a provided on the skin side.

As the skin material 1, a slab urethane foam having a density of 0.02 to 0.05 g / cm ³ on the back surface of a thin knitted polyester fiber, a skin material lined with a thickness of 2 to 4 mm, or a thin vinyl chloride sheet is used. A skin material having a slab urethane foam and a polyethylene foam lined in order on the back surface was used.

As the base material 2, a polyethylene resin fiber is dispersed in a random direction in a glass fiber having a fiber length of 40 mm to 50 mm at a weight fraction smaller than that of the glass fiber, and the uniformly mixed fibers are compacted by needling. A base material was used in which a polyethylene resin film having a thickness of 100 to 200 μ was arranged on both sides of the fiber mat.

FIG. 2 is a conceptual diagram of steps of the present invention.

First, the base material 1 is heated by a heater to bring the base material temperature to about 160 ° C. and put in a softened state capable of being shaped. (A1)

Next, this base material is placed between molds having a clearance of 4 mm between male and female and press-formed, and the pressing force substantially acting on the base material at this time is about 0.1 to 0.2 kg / cm 2.
² and this pressing brings the substrate thickness to 2-5 mm. (A2)

Next, a film-shaped hot melt made of a thermoplastic polyamide-based resin having the same composition is temporarily attached to each laminated surface of the shaped substrate and the skin material to be laminated. (B)

The basis weight of this hot melt is 20 to 10
0 g / m ^2, and the skin side and 30 to 150 g / m ^2.

The base material and the skin material to which the hot melt is applied are heated by separate heating devices until the hot melt applied is softened. (C1)

In the case of this embodiment, the temperature on the substrate side is 90 ° C.
It is optimal when the temperature on the epidermis side is 115 ° C., and the heating temperature is allowed within the range of 10 ° C. above and below.

In this state, the base material and the skin material are stacked with the surfaces to which the hot melt is applied facing each other.
The base material and the skin material are laminated and attached by pressing. (C2, c3)

The pressing at this time is larger than the pressing at the time of shaping the substrate, which is about 0.5 to 0.7 kg / cm ² , and since the pressing is sufficiently large, the hot melt 3a in the softened state, 3b adheres sufficiently to the base material and the skin material,
Furthermore, the hot melts also adhere to each other to form a strong bond.

As another embodiment of the present invention, it is possible to apply the hot melt to the base material prior to shaping the base material.

[0025]

EFFECTS OF THE INVENTION According to the present invention, a thermoplastic resin substrate, in which a suitable surface material adhesion temperature is a relatively low temperature while a suitable shaping temperature of the substrate is a relatively high temperature, particularly a glass fiber-containing material As a method for laminating a skin on a thermoplastic resin substrate, not only can pressure be increased when the substrate and the skin material are adhered to obtain sufficient adhesive strength, but also the sticking temperature of the skin material can be lowered. Therefore, the texture of the skin material is not damaged by heat, and the selection range of the skin material is expanded.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a laminated material to which the present invention is applied.

FIG. 2 is a process conceptual diagram of the present invention.

[Explanation of symbols]

 1 base material 2 skin material 3 hot melt 3a hot melt (base material side) 3b hot melt (skin surface)

Claims (1)

[Claims] 1. A step of heating a thermoplastic resin base material to soften it and press-forming it, and a film-shaped or web-shaped hot melt on each laminated surface of the shaped substrate and the skin material laminated thereon. The step of applying and heating the shaped base material and the skin material respectively, stacking the hot melt application surfaces facing each other, and pressing with a pressure larger than the pressure applied when shaping the base material, and the base material and the skin. A method for laminating a skin on a thermoplastic resin substrate, the method comprising laminating and adhering materials.