JPH03184832A - Method of coating inside of mold in pultrusion - 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 [Field of Industrial Application] The present invention relates to a coating method in pultrusion molding, which is a method for producing fiber reinforced plastics. More specifically, the present invention relates to a method of painting within a mold simultaneously with molding.

[Prior art] The pultrusion method is one of the widely known continuous molding methods for reinforced plastics, and it uses long materials such as long fibers as reinforcing materials to continuously obtain long molded products. This method is characterized by the fact that The application of molded products obtained by this pultrusion method to structural materials, housing-related materials, etc. has been investigated. In expanding the applications of such pultruded materials,
Various methods have been used to color the molded product by painting, but conventional methods for coloring the pultruded product have generally included adding pigments to the pultruded product and directly painting the molded product after molding.

[The problem that the invention attempts to solve]

However, when pigments are added to the compound, there are problems such as deterioration of the physical properties of the molded product, occurrence of color separation, and exposure of glass patterns.Also, in the case of painting after molding, surface treatment of the molded product is required. There were various problems such as poor performance, increased number of steps, and large loss of paint.

On the other hand, recently there has been a strong demand for a manufacturing method that allows high productivity, low cost, and high quality products, and it has become necessary to solve the above-mentioned problems as soon as possible.

[Means to solve the problem]

The present inventors conducted intensive research to solve the above-mentioned problems, and as a result, discovered a method of transferring a coating film in a pultrusion mold at the same time as the molding, and completed the present invention.

That is, the in-mold coating method in pultrusion molding of the present invention is a pultrusion method for producing fiber-reinforced plastic using a long material as a reinforcing material, and a film having releasability on which coating 119 has been formed is heat-cured. This method is characterized in that it is drawn into a mold together with a fiber base material impregnated with a synthetic resin, and a coating film is transferred to the surface of the molded product.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is a flowchart showing one embodiment of the present invention. The required number of rovings 2 are arranged by the roving guide and passed through a resin impregnation tank 3 to be sufficiently impregnated with resin. On the other hand, the film 4 having mold releasability is formed into a uniform coating by a coating device 5, and after being cured by a curing device 6, the film 4 is coated with a roving 2 impregnated with resin in a shaping guide 7. integrated and then drawn into the mold 8,
At the same time as the molding and curing, the coating film is transferred onto the surface of the reinforced resin molded from the film. The coating film can be formed on the releasable film by any method such as roll coke or doctor blade, and the coating film is cured by heating, light irradiation, or the like.

The reinforced resin molded product 9 molded in the mold 8 is pulled out by a take-off machine 10, cut by a cutting machine 11, and then the film is peeled off.

The releasable film used in the present invention may be a film that is not significantly damaged by heat in the mold, such as polyethylene terephthalate film, vinylon film, cellophane film, silicone-impregnated paper, etc. Further, as the paint, unsaturated polyester resin paint, unsaturated epoxy ester resin paint, urethane paint, etc. can be used.

〔Example〕

This will be explained in more detail below with reference to Examples.

Example 1 In the method shown in Figure 1, 0.5 parts of a 6z cobalt naphthenate toluene solution as a curing accelerator and 1 part of methyl ethyl ketone peroxide as a hardening agent were added to a paint using an unsaturated polyester resin as a binder, and the mixture was rolled. It was applied onto a release film using a coater, and after curing, it was introduced into a heating mold together with a reinforcing material impregnated with the other unsaturated polyester compound, and pulled out at a molding temperature of 130°C and a drawing speed of 30 cm/min, and cured. A molded article was created. The adhesion of the surface coating film of this molded product was evaluated using the substrate adhesion test (JIS, Ni-54).
00) are shown in Table 1.

Example 2 In the method shown in Figure 1, a liquid urethane paint was applied onto a release film using a roll coater, and after curing, it was introduced into a heated mold together with a reinforcing material impregnated with an unsaturated polyester compound. , molding temperature 130" C1 drawing speed 30
A molded article was prepared by drawing at a rate of cm/min and curing. As in Example 1, the adhesion of the surface coating film of this molded article was tested using a substrate adhesion test, and Table 1 shows the results.

Comparative Example 1 A reinforcing material impregnated with an unsaturated polyester compound was drawn into a heating mold, and the surface of the molded product was subjected to normal pultrusion molding, and the surface of the molded product was untreated and painted with a paint using an unsaturated polyester resin as a binder. Table 1 shows the results of testing in the same manner as in Example 1.

Table 1 [Effects of the Invention] According to the method of the present invention, since painting is performed in the mold at the same time as molding, the manufacturing process can be greatly simplified, and there is no effect of the paint on the physical properties of the molded product. Moreover, since the paint is applied evenly by supplying the minimum necessary amount of paint, the loss of paint in conventional methods can be significantly reduced.

Furthermore, the adhesion between the molded product and the coating film is improved, the coating film is made more uniform, and the quality is improved, which is of great benefit to industry.

[Brief explanation of drawings]

FIG. 1 is a flow diagram showing an embodiment of the in-mold coating method in pultrusion molding of the present invention. Fiber base material 2: Roving 3: Resin impregnation tank Release film 5: Paint coating device

Claims (1)

[Claims] In the pultrusion molding method that uses elongated objects as reinforcement materials to produce fiber-reinforced plastics, a coated film with mold releasability is placed in a mold together with a fiber substrate impregnated with a thermosetting resin. An in-mold coating method for pultrusion molding, which is characterized by drawing in and transferring a coating film to the surface of the molded product.