JPH10249973A - Resin molding and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and easily prevent void from generating by bonding unwoven fabric or felt for preventing void generation to at least one surface of molding. SOLUTION: Unwoven fabric 5 is, for example, bonded to a surface 6a of hard polyurethane foam resin molding 6. For manufacturing, release agents 3 and 4 are set to the inner surface of a bottom force 1 and a top force 2 respectively, and the unwoven fabric or felt 5 composed of glass fiber, vinyl chloride fiber, etc., is beforehand set by spot bonding using paste to the release agent 4 of the inner surface of the top force 2. A hard urethane foam stock solution is injected into the mold for molding, and released from the mold after hardening, and the release agents 3 and 4 are removed. At this time, the air in the mold and gas generating at the time of molding pass the permeable unwoven fabric 5, thereby they are not accumulated in a gap between the molding and the mold, and diffused uniformly. Thereby no void is generated. The unwoven fabric 5 can be used with bonding to the molding or after removing from the molding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molded product produced by injecting a resin into a mold and molding the same, and a method for producing the same. In particular, the present invention relates to a method for suppressing the generation of voids on the surface of the obtained resin product. Regarding improvement.

[0002]

2. Description of the Related Art A conventional resin molded product is manufactured by subjecting an inner surface of a predetermined mold to a treatment of a release agent or a release material, injecting a resin stock solution, and molding. For example, as a related art related thereto, as disclosed in Japanese Patent Publication No. 5-67416, a mold is treated with a release agent, and a foamed resin stock solution is injected and foamed to produce a foamed molded article. Techniques and the like are known.

[0003]

However, the conventional resin molding technique has the following drawbacks. That is, when a desired resin product is manufactured by injecting and molding a resin stock solution into a mold, a gas is generated when the air or the stock resin solution reacts in the mold, and a large number of gases are generated on the surface of the resin molded product by the gas. Not only does the appearance of voids impair the appearance of the product, but uniform mechanical strength cannot be obtained.

[0004] It is an object of the present invention to remedy the disadvantages of the prior art by providing a molding technique in which the formation of voids can be prevented simply and easily only by using nonwoven fabrics or felts.

[0005]

In order to achieve the above object, a resin molded product according to the present invention is a resin molded product which is molded by injecting it into a mold, wherein at least one surface has a void. The gist is that a nonwoven fabric or felt for preventing generation is adhered.

According to a second aspect of the present invention, there is provided a method for manufacturing a resin molded product, comprising:
The gist of the present invention is to form a non-woven fabric or a felt for preventing void formation on at least one surface of the resin product by self-adhesion to form a single piece.

[0007] The invention of claim 3 is the gist of the invention of claim 2, wherein the nonwoven fabric or the felt is fixed in advance to the inner surface of a mold corresponding to one surface of the resin product via a release material. I do.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION As an embodiment of the present invention, a nonwoven fabric or a felt is used as a member for preventing void formation. This non-woven fabric or felt is fixed to the inner surface of the mold via a release agent at the time of molding the resin stock solution injected into the mold,
Self-adhesive to at least one surface of the resin molded article.
The nonwoven fabric or the felt is removed from the resin molded article or used while being adhered.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention shown in the drawings will be described below.
FIG. 1 is an explanatory view of one embodiment of a method for producing a resin molded product according to the present invention, wherein 1 is a lower mold constituting a mold of a resin product, and 2 is an upper mold. Release materials 3 and 4 are set on the inner surfaces of the dies 1 and 2, respectively. As the release materials 3 and 4, for example, a commonly used silicon release material is used, but various release materials such as a polyethylene film can be used.

Reference numeral 5 denotes a nonwoven fabric (or felt) such as a glass fiber or a PVC fiber, which is, for example, spotted and fixed to the release material 4 on the inner surface of the upper mold 2 with glue. Thus, the nonwoven fabric 5
A resin stock solution, for example, a hard urethane foam stock solution is poured into a mold in which is set, molded, cured, released from the mold, and the release materials 3 and 4 are removed. As shown in FIG. One surface 6 of the polyurethane foam molded product 6
A product is produced which is self-adhered to a.

In this case, the gas generated when the air in the mold or the resin solution reacts is diffused by the nonwoven fabric 5, so that
The generation of voids is suppressed on the surface of the molded article 6 to which the nonwoven fabric 5 is adhered, so that it is completely invisible. That is,
Since the air in the mold and the gas generated during molding pass through the nonwoven fabric 5 having air permeability, the air is uniformly diffused without accumulating in the gap between the molded body and the mold, and no void is generated. Since the generation of voids is due to the presence of gas on the surface of the molded body, if this gas is uniformly diffused to the outside by the nonwoven fabric, the generation of voids is suppressed and reduced, and the surface of the molded body exhibits a good appearance. . Moreover, not only can the uniform mechanical strength be obtained by significantly reducing the voids,
Selecting an appropriate nonwoven material has the effect of further reinforcing the mechanical strength of the molded article.

The non-woven fabric 5 may be normally adhered only to the upper surface of the molded product 6 as shown in FIG. 2, but may be adhered to other surfaces requiring a good appearance with few voids as necessary. You may do so. In addition, felt may be used instead of the nonwoven fabric, and the nonwoven fabric 5 may be used while being adhered to the molded product, or may be used after being removed. For example, the nonwoven fabric can be used as a support (support) for a pipe in a state where the nonwoven fabric adheres to one surface of the polyurethane molded product. In this case, the effect of reinforcing the mechanical strength is obtained as described above.
Further, the present invention is applicable to a room-temperature reaction-type resin molded article for injection foaming and the like and a method for producing the same.

[0013]

As described above, according to the present invention, the generation of voids can be prevented by a very simple method of simply adhering a nonwoven fabric or felt to a resin molded product, and the practical effect is very large. It is.

[Brief description of the drawings]

FIG. 1 is an explanatory view of one embodiment of a manufacturing method of the present invention.

FIG. 2 is a perspective view showing one embodiment of the resin molded product of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower die 2 Upper die 3 Release material 4 Release material 5 Nonwoven fabric 6 Molded product

Claims (3)

[Claims] 1. A resin molded product obtained by injecting into a mold and molding, wherein at least one surface of the resin molded product is bonded with a nonwoven fabric for preventing generation of voids or a felt. 2. A method of molding a desired resin product by injecting a resin into a mold, wherein a non-woven fabric or a felt for preventing void formation is self-adhered to at least one surface of the resin product to be integrally molded. Manufacturing method of resin molded product. 3. The method of manufacturing a resin molded product according to claim 2, wherein the nonwoven fabric or the felt is fixed to an inner surface of a mold corresponding to one surface of the resin product via a release material in advance. Method.