JPS61146518A - In-molded product having flexible sheet - Google Patents

Abstract

PURPOSE:To make a foamed resin easy to penetrate between yarns of cloth at the time of molding and to enhanced appearance by eliminating the collapse of a flexible sheet, by molding the foamed resin on the cloth constituting the back surface of the flexible sheet by an in-mold system. CONSTITUTION:A PP resin having a foaming agent added thereto is subjected to injection molding in a molten state, while foamed under pressure of 50-150kg/cm<2>, to be molded on the back surface of the cloth 2 being the back side of a flexible sheet 1. By this method, the PP resin is made easy to penetrate between yarns of the cloth at the time of a foaming process and, therefore, the injection pressure of the resin can be lowered without lowering the bonding strength between the foamed resin base material 5 and the cloth and, as a result, the collaspe of the foamed layer 3 and a decorative layer 4 is eliminated to enable the enhancement of appearance. Because the foamed resin base material 5 is molded while foamed in a mold, volumetric expansion is generated by foaming even after the filling of the resin was completed, pressure holding is dispensed with.

Description

[Detailed Description of the Invention] Object of the Invention (Field of Industrial Application) The present invention relates to various in-mold molded products such as automobile interior parts and indoor equipment products, and more specifically, the present invention relates to various in-mold molded products such as automobile interior parts and indoor equipment products, and more specifically, This invention relates to an in-mold molded product having a sheet.

(Conventional technology) In-mold molded products with various flexible sheets, such as automobile interior parts and indoor equipment products, have an excellent appearance and hide defects such as scratches and color unevenness on the surface of the resin base material. For this purpose, it is useful to decorate the same surface with scraped wood. Furthermore, in addition to the appearance problem, it is desirable to provide, for example, a foam layer on the surface of the resin base material in order to make it soft to the touch.

On the other hand, when molding the in-mold molded product, ``With the flexible sheet housed in the mold, resin is injected into the mold at a pressure of, for example, 300 to 400 kg/cIiI, and the flexible sheet is A resin base material is adhered to the back side of the adhesive sheet. However, this molding method requires high molding pressure,
Since it is necessary to apply the high pressure for a certain period of time even after the resin injection is completed, the flexible sheet and the decorative layer such as fabric provided on the surface of the sheet may be crushed, which may impair the appearance. There's a problem.

Further, the in-mold molded product has a problem in that when the resin base material has a boss portion or a rib, a recess called a sink is formed on the surface of the resin base material.

(Problems to be Solved by the Invention) The present invention solves the problems that exist in the above-mentioned conventional techniques, that is, the molding pressure is high, and it is necessary to keep the high pressure applied for a certain period of time even after the resin injection is completed. The problem is that the flexible sheet collapses and the decorative layer such as fabric provided on the surface of the sheet collapses, impairing the appearance, and if the resin base material has bosses or ribs, the resin base material The aim is to solve the problem that recesses called sink marks are likely to form on the surface of the steel.

Structure of the Invention (Means for Solving the Problems) In order to solve the above problems, the present invention forms a flexible sheet by laminating a soft skin layer on the surface of cloth, and also The structure is such that a foam base material made of synthetic resin is integrally foam-molded on the back side of the cloth during in-mold molding.

(Function) By adopting the above configuration, the present invention allows the foamed resin to penetrate between the threads of the cloth during molding, thereby increasing the bonding force between the resin base material and the cloth. It is not necessary to fill the foamed resin 100%, the injection pressure can be lowered, and the flexible sheet does not collapse. Further, volumetric expansion occurs due to foaming even after the filling of the resin is completed, so that no holding pressure is required, and sink marks do not occur even when the base material has ribs or the like.

(Example) Hereinafter, an example in which the present invention is embodied in an automobile center pillar interior material, which is an in-mold molded product, will be described in the first example.
This will be explained based on FIGS.

In the drawings, reference numeral 1 denotes a flexible sheet provided on the surface of the center pillar interior material, and is composed of a cloth 2 and a foam layer 3 integrally laminated on the surface thereof. As the cloth 2, for example, a woven cloth such as a plain woven cloth made of polyester fiber yarn, or a non-woven cloth is used. Further, the foam layer 3 is formed of, for example, a cross-linked or non-cross-linked vinyl chloride paste resin to which a foaming agent is added.

In addition, urethane resin, polyvinyl chloride (PVC)
) resin, polyester resin, etc. may be used.

4 is a decorative layer provided on the surface of the foam layer 3,
For example, it is made of cross-linked or non-cross-linked vinyl chloride paste resin to which no blowing agent is added, and its surface is patterned. In addition to this, fabric may also be used.

Reference numeral 5 denotes a foamed resin base material for the center and collar interior materials, which is formed by injecting polypropylene (PP) resin onto the back surface of the cloth 2 and performing foam molding. Instead of this PP resin, acrylonitrile-butadiene-styrene (AB
S) A hard foam resin material such as resin or hard urethane resin may be used.

By the way, the boundary portion of the foamed resin base material 5 with respect to the cloth 2 is affected by the injection pressure during molding and the volumetric expansion during foaming.
As shown in FIG. 2, it hardens after penetrating between the threads of cloth 2. Also, the heat during injection molding causes the PP resin to melt a portion of the thread and fuse with it. Therefore, the cloth 2 is firmly joined to the foamed resin base material 5 by mechanical anchoring effect or fusion.

Next, an in-mold molding method for the center pillar interior material of this embodiment will be explained.

First, as shown in FIG. 3, the foam layer 3 is applied to the surface of the cloth 2.
A decorative layer 4 is formed on the surface of the foamed layer 3, and the resulting flexible sheet 1 and decorative layer 4 are trimmed to a larger size to correspond to the shape of the interior material. As shown in FIG. 4, it is set in the movable mold 6 of the injection molding apparatus so that the decorative layer 4 faces the mold surface side. Subsequently, as shown in FIG. 5, the movable mold 6 and the fixed mold 7 are matched, and molten PP resin containing a foaming agent is injection molded at a pressure of 50 to 150 kg/ad to form a flexible sheet. 1 and the decorative layer 4 are pressed against the mold surface of the movable mold 6 by injection pressure, and at the same time, the foamed resin base material 5 is integrally formed on the back surface of the cloth 2.

Now, in the embodiment of the present invention, the back surface of the flexible sheet 1, that is, the back surface of the cloth 2, was injection molded while foaming the molten PP resin with a foaming agent added at a pressure of 50 to 150 kgr/-. , the PP resin easily penetrates between the threads of the cloth 2 during the foaming process, and therefore the injection pressure of the resin can be lowered without reducing the bonding force between the foamed resin base material 5 and the cloth 2, and as a result, the foamed layer 3 and the decorative layer 4 from being crushed, the appearance can be improved.

Furthermore, in this embodiment, the foamed resin base material 5 is molded while the resin is foamed in the mold, so volumetric expansion due to foaming occurs even after the filling of the resin is completed, and therefore no holding pressure is required. Not only this, but also when the foamed resin base material 5 has ribs or the like, it is possible to eliminate sink marks and improve the quality of the product.

Furthermore, in this example, since the base material 5 is formed from a foamed resin, it is only necessary to inject a small amount of the foamed resin, which makes it possible to reduce the weight of the molded product and also to save material costs and reduce costs. realizable.

It should be noted that the present invention is not limited to the configuration of the above-mentioned embodiment, and can be embodied as follows, for example.

(1) Omitting the decorative layer 4.

(2) For example, the material, formation method, etc. of the decorative layer 4 may be changed as follows.

(Another example) As shown in FIG. 6, pile flocking is applied as a decorative layer 8 to the surface of the foamed layer 3 after formation.

■Another example 2 As shown in FIG.
It can be bonded to the foamed layer 3 by adhering it to vinyl chloride paste resin in a paste state.

■Another Example 3 As shown in FIG. 8, a sheet made of various synthetic resins such as polypropylene, urethane, polyethylene, etc. is used as the decorative layer 10.

■Other Example 4 As shown in Figure 9, a decorative layer 11 comprising colors, letters, patterns, etc. is provided on the surface of the foam layer 3 by printing, and a protective coating 12 is applied to the surface using acrylic paint or the like. Coating and forming. Note that the decorative layer 11 may be formed by not only printing but also painting, sputtering, coating, or any other method as long as a thin decorative layer is formed.

■Another Example 5 As shown in FIG. 10, an uneven portion is provided on the surface of the foam layer 3 as the decoration layer 13.

(3) As mentioned above, the cloth 2 is not limited to a plain woven cloth made of polyester fiber yarn, but can be any cloth (whether woven or non-woven) having any grain, thickness, density, yarn type, etc. May be used. The degree of penetration of the synthetic resin varies depending on the texture, thickness, density, etc., and when a nonwoven fabric is used, the synthetic resin will penetrate between the fibers. Furthermore, the presence or absence or degree of fusion with the synthetic resin varies depending on conditions such as the type of thread and injection temperature.

(4) Raise the back side of the cloth 2. In this case, the anchoring effect on the foam layer 3 and the cloth 2 becomes greater, and the bondability can be further improved.

(5) The synthetic resin constituting the foamed resin base material 5 is the PP
The resin is not limited to resins, and various synthetic resins such as polyethylene (PE) resin, polystyrene (PS) resin, ABS resin, methyl methacrylate (PMMA) resin, polyurethane resin, and others can be used arbitrarily.

In particular, when using polyolefin resins such as PP resins and PE resins that have low adhesive properties, the present invention is effective because high bonding strength can be obtained even without an adhesive.

(6) The anchor effect can be achieved by blow molding or injection molding the foamed resin base material 5 instead of injection molding, that is, by pressing the synthetic resin against the cloth 2 with blow pressure or injection pressure. In the present invention, these three molding methods will be collectively referred to as in-mold molding.

(7) In addition to center pillar interior materials, the present invention has been embodied in various resin molded products such as automobile interior parts such as automobile door linings, ceiling materials, and instrument panels, as well as furniture, fittings, and wall materials. can do.

Effects of the Invention As detailed above, 11 In the present invention, the foamed resin is in-molded on the back side of the cloth of the visibility sheet, so the foamed resin easily penetrates between the threads of the cloth during molding, and therefore the foamed resin base material The injection pressure of the resin can be lowered without lowering the bonding force between the flexible sheet and the cloth, and as a result, the flexible sheet can be prevented from collapsing and its appearance can be improved. In addition, volume expansion occurs due to foaming even after resin filling is completed, which not only eliminates the need for holding pressure, but also improves product quality by eliminating sink marks when the base material has ribs, etc. be able to. Furthermore, it is possible to reduce the weight of the molded product, and also to save material costs and reduce costs.

[Brief explanation of drawings]

Figures 1 to 6 show an embodiment in which the present invention is applied to a center pillar interior material of an automobile. Figure 1 is a sectional view of the same embodiment, Figure 2 is an enlarged sectional view, and Figure 3 is an enlarged sectional view. is a sectional view showing the flexible sheet, FIG. 4 is a sectional view showing the state before mold matching during injection molding, FIG. 5 is a sectional view showing the state after mold matching, and FIG. 6 is the above-mentioned embodiment. A sectional view showing another example of
7 is a sectional view showing another example 2, FIG. 8 is a sectional view showing another example 3, FIG. 9 is a sectional view showing another example 4, and FIG. 10 is a sectional view showing another example 5. Flexible sheet 1-L cloth 2, foam layer 3, decorative layer 4, foam resin base material 5°

Claims (1)

[Claims] 1. A flexible sheet is formed by laminating a soft skin layer on the surface of a cloth, and a foamed base material made of synthetic resin is in-mold molded on the back surface of the cloth of the flexible sheet. An in-mold molded product having a flexible sheet that is sometimes integrally foam-molded. 2. The foamed base material made of the synthetic resin is PP resin, AB
An in-mold molded product having a flexible sheet according to claim 1, which is formed by foaming S resin or hard urethane resin. 3. The in-mold molded product having a flexible sheet according to claim 1, wherein the soft skin layer is formed of a vinyl chloride paste resin foam layer.