JPH0242342B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a method for forming overlapping patterns on resin molded products such as vehicle finishes and moldings.

BACKGROUND ART Generally, in vehicle finishers, moldings, etc., the name of the vehicle model, decorative characters, figures, symbols, and other appropriate patterns are printed on the flat surface of the outer surface, which is patterned in a strip shape in a different color. Formation is taking place.

Traditionally, this type of patterning was done by pasting a label with a pattern printed on a flat surface, or by pressing a transfer film, which is a different color from the resin molded product, onto the surface of the resin molded product using a rod-shaped pressing die. Adhering and molding as a transfer film using a hot stamp has been carried out (Japanese Patent Application Laid-open No. 138913/1983). However, when the pattern formed by these films is subjected to severe usage conditions such as those applied to the exterior of automobiles, even if the pattern is not a layered pattern, it can be easily scratched and the base material exposed or peeled off. Also, if the material of the finisher body is made of soft synthetic resin containing a plasticizer, the transfer film may float due to the plasticizer migrating to the outer surface with long-term use. In extreme cases, it will begin to peel off partially, and this will be even more noticeable if it becomes an overlapping pattern.

DISCLOSURE OF THE INVENTION The present invention provides a method for forming a layered pattern on a resin molded product, which can withstand use under severe conditions even with a layered pattern and can be firmly molded without being affected by plasticizers. The purpose is to provide.

That is, in the method for forming overlapping patterns on a resin molded product according to the present invention, sheet materials having different colors and compatibility with each other are placed on the substantially flat surface of the resin molded product in accordance with the formed patterns such as letters, figures, symbols, etc. By sequentially overlapping them and heat welding them with a press mold, a layered pattern integrally fused with each other is formed on the outer surface of the resin molded product.

Embodiments The following description will be made with reference to the drawings.

In the illustrated embodiment, a resin molded product 1 is used as a finisher, a side molding, a bumper, etc. for a vehicle, and a substantially strip-shaped base pattern 2a of a color different from that of the main body of the resin molded product 1 is formed on the substantially flat outer surface portion 11 of the resin molded product 1.
Furthermore, letters and figures of a different color from the base pattern 2a,
It is practiced to overlap and shape the representational pattern 2b such as a symbol.

The resin molded product 1 is made by integrally extruding a core part 12 made of a foamed vinyl chloride resin and an outer part 13 made of a non-foamed soft polyvinyl chloride resin so as to cover the outer surface of the core part 12. is used. In addition, in order to shape the patterns 2a and 2b on this resin molded product 1, it is necessary to have a shape that is compatible with at least the outer shell 13 of the resin molded product 1, which is the shaping surface of the base pattern 2a, and has a different color from the outer surface portion 11. For the representation pattern 2b, a sheet material 4 having a color different from the base pattern 2a and having compatibility therewith is used. For both of them, it is preferable to use a sheet material having a thickness of about 0.05 to 0.1 mm and made of the same soft polyvinyl chloride resin as the outer shell 13 of the resin molded product 1. In addition, those sheet materials 3, 4
is a strip-shaped tape slightly wider than the external dimensions of the shaped pattern, and the outer surface portion 11 is sequentially applied to the end surfaces of the pressing molds 5 and 6 having a shape corresponding to the desired pattern.
Make sure to press against.

First, the sheet material 3 is brought into contact with the outer surface 11 of the resin molded product 1 by being pulled by the downward movement of the press die 5, and then the sheet material 3 is brought into contact with the outer surface 11 of the resin molded product 1.
By lowering the pressing mold 5 until it invaginates inward and heating it, the sheet portion 3a that directly contacts the pressing mold 5 is softened and made into a melted or semi-molten state, and the outer surface of the resin molded product 1 is heated. 11 and are integrated with the resin molded product 1. In this state, when the sheet material 3 is pulled in the left-right direction or upward direction, the sheet material 3 is cut at the boundary line between the welded part 3a and the normal part by the pressing action of the pressing die 5, and it recoils upward. However, only the welded portion 3a remains on the outer surface portion 11 of the resin molded product 1, forming the base pattern 2a. This base pattern 2a
After curing, the sheet material 4 is then press-welded to the base pattern 2a using the press mold 6 in the same manner as described above.
With this pressing, welded portions 4a corresponding to the shapes of letters, figures, symbols, etc. remain within the plane of the base pattern 2a, and are formed as a representational pattern 2b invaginated from the outer surface portion 11 of the resin molded product 1. .

This example has pattern 2 on vehicle finisher 1.
Although shown as suitable for forming the sheet materials 3 and 2b, in addition to the above embodiments, the sheet materials 3 and 4 can be shaped into a predetermined shape in advance and heat-welded with the press molds 5 and 6. 5 and 6 are sheet materials 3,
It may be heated in advance to about 130 to 200°C before crimping in step 4. Further, when the outer surface portion 11 of the resin molded product 1 is invaginated to press-fit the patterns 2a and 2b, the outer surface portion 11 is easily invaginated, and the sheet material 3,
In order to improve the cutting ability of 4, it is best to make the resin molded product 1 elastic by heat-treating it in advance to about 80 to 90 degrees Celsius, which is the glass transition temperature of polyvinyl chloride resin. It can also be given by doing. The patterns 2a and 2b are not buried in the recess formed by the outer surface portion 11 of the resin molded product 1, but are made thicker on the surface of the outer surface portion 11 and are welded and fixed to each other so that they are fused together. You can also do it. Furthermore, the patterns 2a and 2b can be formed by stacking two or more layers.

Effects of the Invention As described above, according to the method of forming a pattern on a resin molded product according to the present invention, the resin molded product and each pattern can be integrally fused by welding sheet materials compatible with each other. Because it is molded, it can withstand severe usage conditions and can be formed into a strong pattern that does not peel off due to plasticizers.

[Brief explanation of the drawing]

Figures 1 and 2 are a perspective view and a cross-sectional view of a resin molded product formed with an overlapping pattern by the method according to the present invention, and Figure 3 is a cross-sectional view.
Figures 5 to 5 are explanatory diagrams of the process of forming an overlapping pattern according to the present invention. 1: Resin molded product, 11: Outer surface part, 2a, 2
b: Layered pattern, 3, 4: Sheet material, 5, 6: Press mold.

Claims (1)

[Scope of Claims] 1. Sheet materials having different colors and compatibility with each other are sequentially stacked on the substantially flat outer surface of a resin molded product according to a desired shape pattern such as letters, figures, symbols, etc., and pressed using a press mold. A method for forming an overlapping pattern on a resin molded product characterized by heat welding. 2. The method of forming a pattern according to claim 1, wherein each of the sheet materials is stacked and welded to the outer surface of a resin molded product using a pressing die. 3. A pattern shaping method according to claim 1 or 2, wherein each sheet material is invaginated into the outer surface of the resin molded product using the pressing die, and is shaped and welded according to the shaped pattern. 4. A pattern forming method according to claims 1 to 3, wherein each sheet material is invaginated and welded to the outer surface of the resin molded product in a state where it is heated to approximately the glass transition temperature to impart elasticity.