JPS61274911A - Preparation of skin integrated resin molded product - Google Patents

Abstract

PURPOSE:To easily prepare a molded product while preventing the wrinkles on the coating surface of a molded product and improving the finishing thereof, by applying an one-pack primer having flat pigment mixed therein to the molding surface of a molding part and subsequently supplying a resin to said molding part to form a resin main body having a primer skin before applying a top coat to said main body. CONSTITUTION:The primer applied to a molding surface is contacted with a resin at the time of molding to be integrally molded and comes to the skin of a molded product. The skin contains flat pigment. As the flat pigment, metal foil pieces with an average particle size of about 10-40mum such as aluminum pieces are used and added in a ratio of about 5-20PHP(a wt. ratio to 100pts. of a resin) to the primer. As the one-pack primer, an urethane resin primer is mainly used and molding is performed by a foam molding process due to injection molding and, as the molding grade resin, a foam moldable resin such as polyurethane is employed. The flat pigment contained in the skin reduces the stress of the primer film at the time of contraction.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for manufacturing a skin-integrated resin molded product, such as in the case of obtaining an automobile glue filet boiler, for example.

(Conventional technology) Integral skin (
When urethane foam (skin integrated type) is painted normally, the painted surface becomes dusty due to shrinkage of the material.
The finish becomes unsightly. For this reason, a top coat is applied to the resin body using a primer. Usually, the primer is applied to the mold surface of the mold and is integrally molded with the resin body. If the primer applied to the mold surface is a two-component type,
After coating to a film thickness of 50 to 150 μm and molding,
Apply a topcoat with a film thickness of 20 to 30 μm, and if the primer is a one-component type, increase the film thickness of the primer to 15 to 30 μm.
After molding and cleaning, putty is applied, and further 70 to 1
Top coat is applied in 2 to 3 times with a film thickness of 00 μm.

According to such conventional methods, in the former case, there is a problem that it takes a long time to dry because the primer film is thick, and in the latter case, extra steps such as putting putty are required, and it is difficult to apply the top coat. This is time consuming and does not prevent the occurrence of dusty surfaces.

(Problems to be Solved by the Invention) This invention attempts to solve the above-mentioned conventional problems, and provides a good finish without causing the painted surface of the molded product in which the skin is integrally molded to become dusty. It is an object of the present invention to provide a method for manufacturing a skin-integrated resin molded product that is easy to obtain and implement.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the means of the present invention is to use a flat pigment when obtaining a resin molded product in which the resin body and the skin are integrally molded and the skin is painted. After coating the mixed one-component primer on the mold surface of the molding part of the mold, the resin is supplied to the molding part to form a resin body having a skin made of the primer, and then a coating is applied to the surface of the resin body. It is designed to be coated with a top coat. As the above-mentioned flat pigment, pieces of metal foil such as aluminum with an average particle diameter of about 10 to 40 μm are used, and the pigment is applied to the paint at about 5 to 20 PHR (
It is added at a ratio of 100% by weight). As a one-component type primer, a urethane resin primer is mainly used. The molding is performed by foam molding such as injection molding. The resin used for molding is a resin that can be foamed, such as polyurethane.

(Function) The primer applied to the mold surface is bonded to the resin during molding and is integrally molded. The primer is considered to be the skin of the molded product. This epidermis contains flattened pigments. When painting the skin, the flat pigment on the skin reduces the stress when the applied paint film shrinks, and does not cause dusting on the surface.

(Example) An embodiment of the present invention will be described below.

First, prepare a primer. In this example, we use a urethane resin-based one-component primer (R-
The primer was prepared by adding aluminum paste (for example, Aluminum Paste M601 manufactured by Asahi Kasei Corporation) to the 188 primer (using 188 primer) at a ratio of 10 PHR and stirring and mixing. On the other hand, a mold for molding an automobile glue filet boiler is prepared, and a primer is applied to the entire molding surface of the mold. The primer is applied so that the dry film thickness is 30 μm (a film thickness test is conducted in advance). After the mold is closed, urethane is injected into the mold.
Fire to fill the mold.

Thereafter, the mold was unclamped and demolded to obtain a molded product of a predetermined shape. The molded product had a primer coated on its surface, no pinholes were observed, and had good moldability. then i
After cleaning the molded product with i, t-trichloroethane vapor, apply a one-component urethane paint (using Raflex 1300 manufactured by Kansai Paint Co., Ltd.) to the surface of the molded product so that the dry film thickness is 30 μm. The product was then baked at 120° C. for 40 minutes to obtain a surface-coated product.

As shown in Tables 1 and 2, the obtained products were of better quality than conventional products manufactured by conventional methods.

Table 1 Table 2 Conventional products I to ■ all used primers containing no metal foil pieces.

The "clearness value" in Table 1 is the degree of clarity and gloss measured with an optical needle and expressed numerically.

(Effects of the Invention) Since the present invention is implemented as the above-mentioned problem-solving means, the desired problem is solved. That is, in the present invention, the coated surface of the skin surface of the molded product in which the skin is integrally molded can be prevented from becoming dusty and can have a good finish. Further, the present invention is easy to implement without requiring the effort of putting putty in unlike the conventional method.

Claims (5)

[Claims] (1) When obtaining a resin molded product in which the resin body and the skin are integrally molded and the skin is painted, after applying a one-component primer mixed with a flat pigment to the mold surface of the molding part,
A method for manufacturing a skin-integrated resin molded article, comprising supplying resin to the molding part to form a resin body having a skin made of a primer, and then applying a top coat to the skin of the resin body. (2) The method for producing a skin-integrated resin molded article according to claim 1, wherein the flat pigment has a flat shape with a diameter of about 10 to 40 μm, and the amount of pigment mixed is about 5 to 20 PHR. (3) The method for manufacturing a skin-integrated resin molded article according to claim 1, wherein the one-component primer is a primer made of urethane resin. (4) The method for producing a skin-integrated resin molded article according to claim 1, wherein the resin supplied is a polyurethane resin. (5) The method for producing a skin-integrated resin molded article according to claim 1, wherein the top coat is a one-component urethane paint.