Resin component and method for manufacturing the resin component

Abstract

To provide a resin component reducing load on the environment due to manufacture: and to provide a method for manufacturing a resin component.SOLUTION: A method for manufacturing a resin component comprises: a base coating process for coating the surface of a resin substrate with a base coating material in which an electrical conduction material is added; a drying process for drying the base coating material coated in the base coating step; a clear coating step for electrostatically coating the surface of the base coating material dried in the drying process with a thermosetting type clear coating material; and a thermosetting process for heating and curing the clear coating material electrostatically coated in the clear coating process.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to resin parts such as exterior parts of automobiles and a method for manufacturing resin parts.

Background Art

[0002] Conventionally, as this type of resin part, for example, the one shown in Patent Document 1 is known. Such a resin part has a configuration in which an electroconductive primer paint, a base paint, and a clear paint are sequentially applied to the surface of a resin base material.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when manufacturing the above resin parts, heating for drying is required after the application of the electroconductive primer paint and after the application of the base paint, and heating for curing the clear paint is required after the application of the clear paint. That is, when manufacturing the above resin parts, three heating steps are required. Since the heating step involves energy consumption and carbon dioxide emissions, it places a burden on the environment. In recent years, it has been desired to reduce the environmental burden in manufacturing resin parts.

Means for Solving the Problems

[0005] Hereinafter, each aspect of a resin part and a method for manufacturing a resin part for solving the above problems will be described. [Aspect 1] A method for manufacturing a resin component, comprising: a base coating step of coating the surface of a resin base material with a base paint to which a conductive material is added; a drying step of drying the base paint coated in the base coating step; a clear coating step of electrostatically coating a thermosetting clear paint on the surface of the base paint dried in the drying step; and a thermosetting step of heating and curing the clear paint electrostatically coated in the clear coating step.

[0006] According to the above configuration, since the conductive material can impart conductivity to the base paint, the clear paint can be electrostatically coated on the surface of the base paint without applying a conductive primer between the base material and the base paint. Therefore, the coating process of the conductive primer is not required, so that the energy consumption and carbon dioxide emissions associated with the coating process of the conductive primer can be reduced compared to the case where the coating process of the conductive primer is required. Thus, the environmental load associated with manufacturing can be reduced.

[0007] [Aspect 2] The method for manufacturing a resin component according to [Aspect 1], wherein the conductive material is a conductive polymer or conductive carbon. According to the above configuration, conductivity can be more reliably imparted to the base paint.

[0008] [Aspect 3] The method for manufacturing a resin component according to [Aspect 1] or [Aspect 2], wherein the base paint is an aqueous paint. According to the above configuration, since the base paint has conductivity, the base paint can be electrostatically coated on the surface of the base material.

[0009] [Aspect 4] A resin component, comprising: a resin base material; a base paint film formed on the surface of the base material and to which a conductive material is added; and a thermosetting clear paint film formed on the surface of the base paint film. According to the above configuration, since there is no conductive primer between the base material and the base coating film, the coating process of the conductive primer becomes unnecessary when manufacturing the resin component. Therefore, compared with the case of manufacturing a resin component in which a conductive primer exists between the base material and the base coating film, the energy consumption and carbon dioxide emissions associated with the coating process of the conductive primer can be reduced. Accordingly, the environmental load associated with manufacturing can be reduced.

Effects of the Invention

[0010] The present invention has an effect of reducing the environmental load associated with manufacturing.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0012] Hereinafter, one embodiment will be described with reference to the drawings. <Resin Component 11> As shown in FIG. 1, the resin component 11 is used, for example, for exterior components of an automobile. The resin component 11 has a three-layer structure including a resin base material 12, a base coating film 13 formed on the surface of the base material 12, and a clear coating film 14 formed on the surface of the base coating film 13.

[0013] The base coating film 13 is composed of a base paint which is a colored aqueous paint. A conductive material 15 is added to the base coating film 13. The conductive material 15 is composed of, for example, a conductive polymer or conductive carbon. As the conductive polymer, for example, those of polythiophene-based, polyaniline-based, polypyrrole-based, etc. are used. As the conductive carbon, for example, carbon nanotubes, carbon black, etc. are used. The clear coating film 14 is composed of a colorless and transparent thermosetting clear paint.

[0014] <Manufacturing method of resin component 11> As shown in FIGS. 1 and 2, the resin component 11 is manufactured by sequentially going through a base material molding process, a base coating process, a drying process, a clear coating process, and a thermosetting process.

[0015] In the base material molding process, the base material 12 is molded by, for example, injection molding of a synthetic resin. In the base coating process, the surface of the base material 12 molded in the base material molding process is electrostatically coated with a base paint to which the conductive material 15 is added. In the drying process, the base paint coated in the base coating process is dried by heating at a temperature of about 70°C to 90°C, for example.

[0016] In the clear coating process, a thermosetting clear paint is electrostatically coated on the surface of the base paint dried in the drying process. In the thermosetting process, the clear paint electrostatically coated in the clear coating process is heated and cured at a temperature of about 70°C to 130°C, for example.

[0017] <Function of the embodiment> In order to electrostatically coat a non-conductive clear paint in the above clear coating process, the side to be electrostatically coated needs to have conductivity. In this regard, in the manufacturing method of the resin component 11 of this embodiment, since the conductive material 15 is added to the base paint, it is possible to electrostatically coat the clear paint on the base paint without disposing a conductive primer under the base paint.

[0018] <Surface resistivity of the example and the comparative example> A comparative example was a case where a base coating film (dried base paint) was formed on a conventional conductive primer. Example 1 was a base coating film 13 to which carbon nanotubes were added as the conductive material 15. Example 2 was a base coating film 13 to which a polythiophene-based conductive polymer was added as the conductive material 15. Then, the surface resistivity of each of the comparative example, Example 1, and Example 2, and the addition amount of the conductive material 15 in each of Example 1 and Example 2 were shown in the table of FIG. 3.

[0019] As shown in the table of FIG. 3, Example 1 and Example 2 have a surface resistivity equal to or lower than that of the comparative example. For this reason, Example 1 and Example 2 have higher conductivity than the comparative example. Further, in Example 1, although the addition amount of the conductive material 15 is significantly less than that in Example 2, the surface resistivity is lower than that in Example 2. For this reason, it is preferable to use carbon nanotubes as the conductive material 15. This is because the smaller the addition amount of the conductive material 15 to the base coating film 13, the smaller the influence on the color tone of the base coating film 13 by the conductive material 15.

[0020] <Effects of the Embodiment> According to the first embodiment described in detail above, the following effects are exhibited. (1) The manufacturing method of the resin component 11 includes a base coating step of coating the surface of the resin base material 12 with a base paint to which the conductive material 15 is added, a drying step of drying the base paint coated in the base coating step, a clear coating step of electrostatically coating a thermosetting clear paint on the surface of the base paint dried in the drying step, and a thermosetting step of heating and curing the clear paint electrostatically coated in the clear coating step.

[0021] According to the above configuration, since the conductive material 15 can impart conductivity to the base paint, the clear paint can be electrostatically applied to the surface of the base paint without applying a conductive primer between the base material 12 and the base paint. Therefore, since the painting process of the conductive primer becomes unnecessary, the energy consumption and carbon dioxide emissions associated with the painting process of the conductive primer can be reduced compared to the case where the painting process of the conductive primer is required. Accordingly, the environmental load associated with the production of the resin component 11 can be reduced.

[0022] (2) In the method for manufacturing the resin component 11, the conductive material 15 is a conductive polymer or conductive carbon. According to the above configuration, conductivity can be more reliably imparted to the base paint.

[0023] (3) In the method for manufacturing the resin component 11, the base paint is an aqueous paint. According to the above configuration, since the base paint has conductivity, the base paint can be electrostatically applied to the surface of the base material 12.

[0024] <Modification Example> The above embodiment can be implemented with the following modifications. Also, the above embodiment and the following modification examples can be implemented in combination with each other as long as there is no technical contradiction.

[0025] · In the drying process, the base paint may be dried only by blowing air without heating. · The base paint constituting the base paint film 13 is not limited to an aqueous paint and may be an oil-based paint.

[0026] · The conductive material 15 is not limited to a conductive polymer or conductive carbon, and may be, for example, fine powder of a metal. · The resin component 11 is not limited to exterior parts of an automobile, and may be used, for example, as a component constituting the outer wall of a building.

Explanation of Reference Numerals

[0027] 11…Resin Component 12…Base material 13…Base coating film 14…Clear coating film 15…Conductive material

Claims

1. A base coating step of coating the surface of a resin base material with a base paint added with a conductive material, A drying step of drying the base paint coated in the base coating step, A clear coating step of electrostatically coating a thermosetting clear paint on the surface of the base paint dried in the drying step, A thermosetting step of heating and curing the clear paint electrostatically coated in the clear coating step, A method for manufacturing a resin component comprising the steps.

2. The method for manufacturing a resin component according to claim 1, wherein the conductive material is a conductive polymer or conductive carbon.

3. The method for manufacturing a resin component according to claim 1 or claim 2, wherein the base paint is an aqueous paint.

4. A resin base material, A base paint film formed on the surface of the base material and added with a conductive material, A thermosetting clear paint film formed on the surface of the base paint film, A resin component comprising the above.

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