JPS606782B2 - Method for manufacturing patterned plastic molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a plastic molded article having a pattern on its surface.

Various methods have been proposed for applying patterns to curved molded products such as bathtubs and wash basins.

The main methods include manually laminating decorative sheets with patterns on glass cloth or nonwoven fabric when manufacturing glass fiber reinforced plastic (FRP) molded products using the hand lay-up method; SMC(
When manufacturing FRP molded products using a press molding method using a sheet molding compound, there is a method in which a patterned woven fabric is sewn into the shape of a mold, and the molded material is softened onto the mold and press molded. However, with these methods, there are joints between surfaces, and the patterns overlap.
There were drawbacks such as the patterns on adjacent surfaces not being continuous, and the design was unsatisfactory. Another method is known, in which a decorative material is formed by applying a pattern to an acrylic plate by transfer or lamination with a decorative sheet, and then is reinforced by forming an FRP layer on the back surface.
This method eliminates defects such as overlapping patterns and discontinuity, but since the surface of the molded product obtained is made of acrylic resin, the surface hardness, heat resistance, and chemical resistance are insufficient. In particular, it lacked boiling resistance, so even if it was molded into a bathtub, it could only be used for water-filling purposes. The present invention has been made in view of the above points, and it is an object of the present invention to provide a method for manufacturing a patterned plastic molded product that can completely satisfy both the design aspect and the performance aspect. be.

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

First, as shown in FIG. 1, a mold release agent 2 and a polyester resin 3 are sequentially applied to a mold 1 to form a transfer target. Then the second
As shown in the figure, a transfer film with an arbitrary pattern 5 applied to a water-soluble film 4 is floated on water 6, and after the water-soluble film dissolves in the water and only the pattern remains on the water surface, as shown in Figure 3. The paint or ink forming the pattern is activated by spraying the solvent 7 onto the pattern surface. Next, as shown in FIG. 4, when the object to be transferred is pressed from above the pattern surface, the pattern is brought into close contact with the surface of the object to be transferred due to the water pressure.

Next, after the pattern has completely adhered, the object to be transferred is pulled out of the water and molded by pouring resin concrete onto the pattern surface as shown in Figure S, or using a normal method such as hand lay-up using FRP molding material. Next, as shown in Fig. 5, when the mold is removed from the mold, a plastic molded product having a continuous pattern on the surface is obtained.
Those commonly used for FRP molding can be used.

Please note that the polyester resin should be transparent or semi-transparent, and should be semi-cured by heating in consideration of handling and the effects of water pressure during transfer.
Polyvinyl alcohol is selected in consideration of printing suitability, etc. of a film made of water-soluble resin such as methylcellulose, casein, and gum arabic.

Any paint or ink can be used as long as it is insoluble in water, and the pattern can be selected from various patterns such as letters, symbols, woodgrain patterns, abstract patterns, marble patterns, etc.

As the solvent, ethyl acetate to toluene, acetone, methyl ethyl ketone, butazole to butyl acetate, and other conventionally known solvents can be used alone or in combination.

After transferring the pattern, a colored layer can be provided if necessary.

The colored layer is made of a polyester resin mixed with a coloring agent, and serves to hide the color of the molding material such as resin concrete or FRP material that will be formed later. In addition,
Resin concrete refers to resin-reinforced concrete, which is a mixture of synthetic resin and inorganic materials such as alumina.

Also, the L pattern is dried after being transferred, and then resin concrete or FRP material is laminated, but depending on the water-based film used, it may take too long to dissolve, so the transfer is done before the film is completely dissolved. may be carried out.

In that case, a water washing process or the like is provided as a process for removing foreign matter after the pattern is dried. According to the method of the present invention as described above, it is possible to obtain a patterned plastic molded product that has a continuous seamless pattern on its surface, has an excellent design, and has performance equivalent to that of conventional FRP molded products.

Example: Apply wax for template on the surface of a mold having the shape of a bathtub, let it dry, and then spray gel coat resin on it to a thickness of 0.3 to 0.4 sails. It was heated for a period of time to semi-cure.

Next, a transfer film with a marble pattern printed on a 30mm thick water-soluble polyvinyl alcohol film using polyester ink was floated on the surface of an aquarium filled with 20oG water with the pattern side facing up for 3 minutes. After the polyvinyl alcohol film is left to dissolve, a mixed solvent is sprayed onto the patterned surface to activate the ink, and then a mold coated with the gel coat resin is placed in contact with the patterned surface and allowed to settle in water. The pattern was transferred.

After the ink dries, a polyester resin mixed with titanium oxide is applied and semi-cured.Then, resin concrete is poured and molded, and when the whole is removed from the mold, the surface is patterned continuously and integrally. I got a marble bathtub.

[Brief explanation of the drawing]

Each of the drawings shows an example of the method of the present invention, and the first drawing shows a cross-sectional view of a mold coated with gel coat resin, the first drawing shows an explanatory diagram of the transfer sheet floating on the water surface, and the third drawing shows the water surface. An explanatory diagram of the state in which solvent is sprayed onto the pattern left on the surface. F.R.
Figure S shows a cross-sectional view of the molded product after it has been removed from the mold. Wealth... Mold dew... Mold release agent ~ 3... Gel coat resin... Water lacquer film Silkworm... Pattern, S... Water 7...
...Solvent "Momo...Resin concrete or FRP layer. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1 After applying a mold release agent to the mold and applying a transparent or colored transparent polyester resin on top of it and semi-curing it, a pattern is applied to the applied surface by transfer, and a colored layer is applied on top of it as necessary. After the installation, resin concrete is poured or ordinary FRP molding is performed, and the transfer method is to apply a desired pattern to a water-soluble film using paint or printing ink, and then place the patterned surface on top of the transfer film. After the water-soluble film has dissolved, a solvent is sprayed onto the patterned surface to activate the paint or printing ink, and then a polyester resin is applied and a semi-cured mold is pressed onto it. A method for producing a patterned plastic molded product, which comprises using a method of transferring the pattern onto the polyester resin surface of a mold.