JPH01237119A - Manufacture of synthetic resin molded product with identifying indication - Google Patents

Abstract

PURPOSE:To manufacture a synthetic resin molded product with identifying patterns rich in solid feeling by spreading and softening an outer surface layer of given tone and a base layer of a laminated material by means of projected sections of a mold and embracing and fixing an expanded section on the periphery by a molded product main body formed by foam expanding an intermediate material. CONSTITUTION:Projected sections 13, 14 and 15 of given height with a profile of identifying indication are provided in a cavity 11. A laminated material 2 consists of an outer surface layer 2a of given tone and a synthetic resin base layer 2b having a large induction loss. The outer surface layer 2a is brought into contact with a cavity surface 12, and the laminated material 2 is fitted and mounted on the inner sections of the projected sections 13, 14 and 15 and then an intermediate material 3 is installed and mold clamped. Heat is self-developed in the base layer 2b and the layer is softened by applying high currency voltage to a mold 1, and expanded starting the projected section 13 to form an expanded section 2c, while the temperature of the intermediated material 3 rises to heat a foaming agent and foam expands. Therefore, a periphery forming the expanded section 2c of the base layer 2b bites into the inner section of a molded product main body 3' which has completed foaming and cured so that the molded product main body 3' embraces the laminated material 2 to cure it integrally.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing a synthetic resin molded article in which identification marks such as letters, numbers, and symbols are attached and molded on the outer surface.

2. Description of the Related Art Conventionally, for example, when a decorative plate for a car body is made of synthetic resin, letters and numbers are printed on its outer surface by hot stamping or welding a resin film, as shown in Japanese Patent Laid-Open No. 59-54511. , symbols, and other identification markings are usually attached and molded. Furthermore, in Japanese Patent Application Laid-open No. 58-142828, a preformed product made of a decorative member and a pre-foamed thermoplastic resin is mounted in the cavity of a mold having electrical insulation and heat resistance, and a high frequency voltage is applied. A method is disclosed in which the preform is foamed and bonded to a decorative member by applying an electric current to the preform.

Problems to be Solved by the Invention However, with this synthetic resin molded product, the identification mark cannot withstand harsh usage conditions and tends to peel off, and the shape is flat and lacks a three-dimensional effect, so it is not decoratively satisfactory. isn't it.

In (2), an object of the present invention is to provide a method for producing a synthetic resin molded product that can be firmly integrated with the molded product body and has a distinctive pattern with a rich three-dimensional effect.

Means for Solving the Problems In the method of manufacturing a synthetic resin molded product having an identification pattern according to the present invention, a laminate material is prepared that includes an outer surface layer having a predetermined color tone and a base material layer formed of a synthetic resin with a large dielectric loss. Identifies the character as a linear member.

It is molded into a planar shape that corresponds to the identification mark such as numbers and symbols, and its outer surface layer is brought into contact with the cavity surface of a mold made of a material with low dielectric loss to form an annular shape corresponding to the outline shape of the identification mark. The laminate material is fitted and placed inside a convex portion that rises from the cavity surface at approximately the same height or slightly higher than the thickness of the outer surface layer of the laminate material, and is lower than the thickness of the laminate material, and is then placed in the mold. 8 After assembling the intermediate material of the molded product body, which is formed into an unfoamed or intermediate foamed state by mixing a synthetic resin with a large electric loss and a foaming agent that foams when heated, into the cavity mold and clamping the mold, a high-frequency voltage is applied. When the application is applied, the base material layer of the laminated material spreads from the annular protrusion and softens at least within the gap remaining between the annular protrusion and the intermediate material of the molded product body to form a bulge, and the intermediate material of the molded product body The molded product body and the laminated material are fixedly molded together by foaming and expanding the material.

Function: In this manufacturing method, the base material layer of the laminated material, to which the outer surface layer having a predetermined color tone is firmly bonded in advance, spreads out from the convex part of the mold and softens, and the intermediate material is foamed and expanded to form the molded product body. By holding and fixing the bulge on the periphery, the laminated material is integrally molded into the main body of the molded product as an identification mark, so the identification mark does not come off even under severe usage conditions, and the outline of the identification mark remains unchanged. Since the outer surface layer of the laminated material protrudes from the outer surface layer of the laminated material, it can be shaped like a monk as an identification mark with a rich three-dimensional effect.

Embodiments will now be described with reference to the accompanying drawings.

This manufacturing method is applied, for example, to molding synthetic resin molded products with identification displays such as letters, numbers, and symbols on the outer surface, such as decorative plates installed on the body of automobiles.
This can be done by integrally fixing and molding the laminate 2, which has been shaped and molded into a planar shape corresponding to the identification mark, using the mold 1 shown in FIG. 1, and the intermediate material 3 of the molded product body.

The mold 1 includes a core mold 10 and a cavity mold 11, which are made of a material with low dielectric loss such as polyolefin resin, fluororesin, silicone resin, or plaster. Cavity mold 1 of the mold 1
1 is provided with convex portions 13, 14, and 15 in an annular shape corresponding to the contour shape of the above-mentioned identification mark and protruding to the cavity surface 12 at a predetermined height as described later, in accordance with the number of monk shapes of the identification mark. . As shown in FIG. 2, the laminated material 2 consists of an outer surface layer 2a made of a material having a predetermined color tone, and a base layer 2b made of a synthetic resin with a large dielectric loss. These are firmly laminated and fixed in advance by adhesion or welding, and the outer surface layer 2a is formed of the convex portions 13, 14, .
A wide sheet material formed to have the same thickness as the protruding dimension of 15, or slightly thinner so that the convex portions 13, 14, and 15 contact the base material layer 2b is shaped into a predetermined shape with a sharp blade or the like. It can be formed by stamping. The outer surface layer 2a can be formed using an appropriate material with a smaller dielectric loss than the base material layer 2b, and when it is shaped as an identification mark that combines several letters, numbers, symbols, etc., each can be of the same color. Alternatively, it is preferable to use a material having different color tones and exhibiting a different color from the molded product body formed from the intermediate material 3. The base material layer 2b is formed of a material with large dielectric loss such as polyvinyl chloride resin, ABS resin, or polyamide resin, and by mixing powder such as metal oxide or carbon inside, the base material layer 2b is It is preferable that the material layer 2b is heated to a high temperature with higher efficiency than the outer surface layer 2a, and it is preferably formed of a material having the same color and compatibility with the intermediate material 3 of the molded product body. Intermediate material for molded product body 3
The method uses a thermoplastic synthetic resin with a large dielectric loss such as polyvinyl chloride resin, ABS resin, or polyamide resin mixed with a foaming agent that foams when heated. It is preferable to use a molded product that has a smaller outer shape and a substantially similar shape than the molded product itself without completing the process.

When manufacturing a synthetic resin molded product using these materials, the outer surface layer 2a is brought into contact with the cavity surface 12 of the mold 1, and the laminate material 2 is fitted and placed inside the annular convex portion 13° 14.15. Thereafter, the intermediate material 3 of the molded product main body is assembled into the cavity die 11 of the mold 1 by being superimposed on the base material layer 2b, and the mold is clamped. In this mold clamping state, as shown in FIG. Since it is located low, at least a gap W1 remains between the annular convex part 13 and the intermediate material 3 of the molded product body, and also between the adjacent convex parts 13, 14, 15, and between the intermediate material 3 and the cavity surface. A space W2 is created between the two. When a high frequency voltage is applied to the mold 1 in this state,
As shown in FIG. 4, the base material layer 2b of the laminated material 2, which has a large dielectric loss, self-heats and becomes soft, and expands to the convex portion 13 and the interval W1 to form a bulging portion 2c, and at the same time, the intermediate material 3 also has a dielectric loss. Since the is large, the temperature is increased in the same way to heat the foaming agent and the interval W1
．． The foam expands to fill the space W2. Therefore, as shown in FIG. 5, the periphery of the base material layer 2b forming the bulging portion 2c bites into the inside of the molded product body 3' which has completed foaming and hardens, so that the molded product body 3' becomes a laminated material. 2 are integrally hardened together so as to embrace each other. At this time, the outer surface layer 2a of the laminated material 2 is not softened by heating because the mold 1 is made of a material with small dielectric loss, and therefore does not deform. As shown, even if the base material layer 2b of the laminated material 2 flows, since the base material layer 2b and the intermediate material 3 have the same color and are compatible, they completely fuse together and present a boundary line that is visible from the outer surface side. Not at all.

Moreover, the intermediate material 3 is foamed, but the mold 1 is not heated.
Since the outer surface side in contact with the cavity surface 12 is constantly cooled compared to the inside, a skin layer with no exposed air bubbles is formed and a clean outer surface is obtained.

After molding the synthetic resin molded product in this way, if the mold is opened after cooling, the outer surface layer 2 of the laminated material 2 will appear as shown in FIG.
An identification mark can be formed on the outer surface layer 2a of the molded product body 3', and the outer surface layer 2a is firmly bonded to the base material layer 2b in advance. Since the peripheral edge of the layer 2b forming the bulging portion 2C is bitten and mechanically fixed, no peeling occurs even under severe usage conditions. Further, the outline of the outer surface layer 2a is formed by the concave portions 3'a,
Since the outer surface layer 2a is bordered by 3'b and 3'c, it is possible to express an identification display with an extremely three-dimensional effect from a place where it can be visually recognized as protruding from the outer surface of the molded product main body 3'. .

Effects of the Invention As described above, according to the method for manufacturing a synthetic resin molded product according to the present invention, an identification mark that does not peel off even under severe usage conditions and has a rich three-dimensional effect can be accurately integrated on the outer surface of the molded product body. It enables molding.

[Brief explanation of the drawing]

Fig. 1 is a side cross-sectional view of a mold in which various materials are assembled in the method for manufacturing synthetic resin molded products according to the present invention, Fig. 2 is a partial cross-sectional view of a laminate used in the same method, and Fig. Fig. 4.5 is a partially enlarged sectional view showing the manufacturing process of a synthetic resin molded product using the same mold, and Fig. 6 is a partially enlarged sectional view of the mold shown in the figure. FIG. 2 is a front view showing a synthetic resin molded product manufactured by the method. 1: Molding mold, 12: Cavity surface, 13, 14.15:
Convex portion, 2: Laminated material, 2a: Outer surface layer, 2b: Base material layer, 3
: intermediate material, 3': molded product body, 2c: bulging part. Patent applicant Hashimoto Forming Industry Co., Ltd. Figure 4 Figure 5 C

Claims (1)

[Claims] Laminated material (2) consisting of an outer surface layer (2a) having a predetermined color tone and a base layer (2b) formed of a synthetic resin with large dielectric loss
A mold (1) is formed into a planar shape corresponding to the identification display such as letters, numbers, symbols, etc. as a shaping member for the identification display, and the outer surface layer (2a) is made of a material with small dielectric loss.
) in contact with the cavity surface (12) of the laminate (2) in an annular shape corresponding to the contour shape of the identification mark.
The laminate material (2) is placed inside the convex portions (13, 14, 15) that rise from the cavity surface (12) at approximately the same height or slightly higher than the thickness of the laminate material (2) and are lower than the thickness of the laminate material (2). Fit and place, and then mold the cavity mold (11) of the mold (1).
After assembling the intermediate material (3) of the molded product body (3'), which is formed into an unfoamed or semi-foamed state by mixing a synthetic resin with a large dielectric loss with a foaming agent that foams when heated, and clamping the mold. , the application of a high-frequency voltage causes the laminated material (2
) of the base material layer (2b) with annular convex portions (13, 14, 15)
The intermediate material (3) of the molded product body (3') is expanded and softened to form a bulging portion (2c), and the molded product body (3') and the laminate material (2) are fixed together by foaming and expanding. 1. A method for producing a synthetic resin molded product having an identification mark, characterized in that the product is molded.