JPS62138238A - Resin molded shape and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a resin molded article and a method for manufacturing the same, and more specifically, to a resin molded article having a foam layer as a component and a method for manufacturing the same. The resin molded product obtained by the present invention is
For example, it is useful for interior parts of automobiles such as console boxes and armrests.

[Conventional technology]

Conventionally, as a manufacturing method for a resin molded product having a skin layer and a foam layer, for example, as described in Japanese Patent Publication No. 11510/1983, thermoplastic resin powder is loaded into a mold and heated to form a sintered layer. A second sintered layer (skin layer) is formed, then a mixed powder of a foaming agent and a thermoplastic resin is loaded inside the sintered layer, and the mold is heated again to form a second sintered layer (foamed layer). There is a way.

[Problem that the invention seeks to solve]

In a resin molded product consisting of a skin layer and a foam layer, for example, when forming a foam layer to improve the feel, it is not necessary to form a foam layer on parts that are not touched by hands. In such a case, if a foam layer is formed over the entire molded product, extra resin will be used.

However, conventionally, no attempt has been made to provide a foam layer partially on the skin layer. In addition, in the method described in the above-mentioned Japanese Patent Publication No. 2003-11000, the foam layer completely covers the inside of the skin layer, and it was not possible to form a foam layer in some areas.

[Means for solving problems]

In view of the problems of the prior art as described above, the present inventors made intensive research efforts, and after forming a thermoplastic resin skin layer on the mold of a mold, the skin layer was bonded to the mold of the mold. By attaching a foamable resin to a part of the opposite surface to form a foam layer, a resin molded product partially having a foam layer was obtained.

This resin molded product has a skin layer that forms the design surface of the molded product, and a foam layer that is formed in close contact with the skin layer so as to cover at least a portion of the back surface of the skin layer.

〔Example〕

FIG. 1 shows an example of the appearance of a resin molded article partially having a foam layer obtained by the present invention. This molded product has the epidermal layer 1
and a foam layer 2, and only a part of the back surface of the molded product is composed of the foam layer.

A method of manufacturing such a resin molded article will be explained with reference to FIGS. 2 to 5. In this method, at least two types of boxes 3 and 4 are used. One of them is a box 2 which has a separator etc. and can contain thermoplastic resin powder or liquid in the metal body inside the box, as shown in FIGS. 2 and 3, and the other box 4.
As shown in FIGS. 4 and 5, there is a separator 5 inside the box 4, and the separator 5 is located slightly below the position of the mold for molding.
They are separated by the thickness of the epidermal layer. The box body 3.4 and the separator 5 can be made of any material such as metal, wood, heat-resistant plastic, etc.

Referring to FIGS. 2 and 3, a thermoplastic resin powder or liquid 6 for the skin layer is stored in a box 3, and a heated mold 7 is attached to the box with a clamp 8.

Next, by rotating the entire box 3 upside down, the thermoplastic resin powder or liquid 6 is poured into a mold 7.
Adheres to and melts on the mold.

Next, the mold 7 to which the resin has been fused is removed from the box 3 and transferred to a box 4 having a separator 5, as shown in FIG. A powder or liquid 9 of thermoplastic or thermosetting resin for the foam layer is stored in one space of the box 4 separated by the separator 5. The resin for the foam layer is a thermoplastic or thermosetting resin containing a known foaming agent such as azosicabonamide. The liquid resin is a resin powder dispersed in a liquid plasticizer, and is in the form of a so-called sol. In the same way as when forming the skin layer, by attaching the mold 7 with the clamp 8 and rotating the entire box 4 upside down, the resin 9 for the foam layer can be heated to form the skin layer. Adheres to the back side of the plastic resin layer and melts.

Next, the mold 7 with the resin attached is removed from the box body 4,
If the resin is insufficiently melted or foamed, it is heated again to melt or foam, and then cooled and demolded.

In this way, a resin molded product having the skin layer 1 and the foam layer 2 on a part of the back surface thereof can be obtained.

In FIG. 4, when the thermoplastic resin 6 for the skin layer in an adhered and molten state comes into contact with the separator 5, the thermoplastic resin 6 is transferred to the separator 5.
However, in reality, the thermoplastic resin 6 is in a semi-molten state, and the thermoplastic resin 6
When the thermoplastic resin 6 comes into contact with the separator 5, it cools and hardens to lose its stickiness.Due to the cooling effect, the thermoplastic resin 6 does not adhere to the separator 5, and the gap between the separator 5 and the mold of the mold 7 is Ideally, they should be separated by the thickness of the skin layer 1, but there is no problem with molding if they are slightly larger or smaller than that.

Note that it is easily understood that by modifying the above method, the foam layer can be provided at any position of the plurality of parts. Further, according to the present invention, it is possible to obtain not only a flat sheet-like molded product as seen in the above-mentioned specific example, but also a resin molded product having an arbitrary shape and partially having a foam layer.

In addition, when a thermoplastic resin is used for the foam layer, elasticity and heat insulation effects can be obtained by the foam layer. In addition, when a thermosetting resin is used for the foam layer, although the foam layer cannot provide the cicada properties, it can provide a heat insulating effect.

Box 3 in Figure 2 contained vinyl chloride resin powder (average particle size 110 ttm) for the skin layer, and box 4 in Figure 4 contained vinyl chloride resin powder (average particle size 110 μm) for the foam layer. . The separator plate 5 of the box body 4 was made of metal, and the gap between it and the molding die was about 1 mm.

The molding mold 7 is heated to 240 to 250°C in a heating furnace, clamped to the box 3, turned over and held for about 6 seconds, then turned over again and returned to the original position. Then, the vinyl chloride resin powder for the skin layer was attached to the mold 7 and melted.

Next, the mold 7 was removed from the box 3, placed on the box 4-H, and clamped. After inverting the box 4 and holding it for about 10 seconds, inverting the box 4 again and returning it to its original position, the mold 7 of the vinyl chloride resin powder layer for the skin layer adhering to the mold 7 is removed.
A polyvinyl chloride resin powder for the foam layer was attached to the opposite side (the back side of the skin layer) and melted.

Then, the mold 7 for molding was removed from the box body 4 and heated to 270°C.
The resin was heated for 2 minutes in a heating furnace to completely melt the resin, and then cooled and demolded.

In this way, a resin molded article having a foam layer on one half of the skin layer was obtained. The thickness of the skin layer of this molded article was approximately 1 mm, and the thickness of the foam layer was approximately 3 mm.

〔Effect of the invention〕

According to the present invention, a resin molded article partially having a foam layer is provided, and resin in unnecessary portions of the foam layer can be saved.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an example of a resin molded product partially having a foam layer according to the present invention, and Figs. 2 to 5 are schematic cross-sectional views illustrating the main parts of the process for manufacturing the resin molded product shown in Fig. 1. be. 1... Epidermal layer, 2... Foaming layer, 3...
・Box for forming skin layer, 4... Box for forming foam layer, 5.
... Separation plate, 6 ... Resin powder for epidermal layer, 7
...Molding mold, 8...Clamp, 9...
Resin powder for foam layers.

Claims (1)

[Claims] 1. A skin layer forming the designed surface of the molded article, and a foam layer formed in close contact with the skin layer so as to cover at least a portion of the back surface of the skin layer. A resin molded product characterized by: 2. After forming a thermoplastic resin skin layer on the mold of the mold, a foamed resin is attached to a part of the surface of the skin layer on the side opposite to the mold to form a foam layer. A method for producing a resin molded article partially having a foam layer, characterized in that: