JP2011162841A - Method of coloring metal formed body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method with which coloring of a metal formed body can be extremely simply performed at a low cost, and coating of a part to be colored and a part not to be colored can be easily performed and in particular, which is suitable for the coloring of a small-sized or minute metal formed body. <P>SOLUTION: The method of coloring the metal formed body formed by forming metal material includes: forming a dyable resin coating layer on at least a part of the surface of the metal material; forming a formed body having a prescribed shape by forming the metal material; and dyeing the resin covering layer by immersing the formed body into a dyeing agent. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for coloring a metal molded body, and more particularly to a method that can be performed at a very low cost as compared with conventional coloring methods when coloring after molding.

  In general, after a predetermined molded product is obtained by punching, pressing, or drawing a metal plate, the molded product is colored. As a method for coloring such a metal molded body, a pre-coral metal (PCM) method, an electrodeposition coating method, an anodizing method, and the like are known.

  Various techniques for coloring metal molded bodies and metal plates have been conventionally proposed. For example, Patent Document 1 describes a method of attaching a colored laminate film to a metal surface, and Patent Documents 2 and 3 describe a method of coloring a metal by shot blasting using colored abrasive grains. Yes. Patent Document 4 describes a method of forming a colored coating on the surface of a metal material using an organic sulfur compound that can form a color forming component by reacting with metal ions.

  Further, Patent Document 5 discloses a method of forming a colored chemical conversion coating on a metal surface by contacting with a solution containing a predetermined compound and an organic acid, a metal compound, and a dye, and Patent Document 6 describes coloring with a composite material. A method of performing a surface treatment such as composite plating by combining a material and a surfactant is disclosed in Patent Document 7 in which a porous metal oxide is colored by depositing an organic pigment in the pores of the metal oxide. However, in Patent Document 8, a metal body having an inorganic compound layer on the surface is immersed for a predetermined time in a treatment solution containing an organic colorant and a hydrosilicofluoric acid aqueous solution in which silicon dioxide is supersaturated. The method of coloring is described.

  Further, as a technique for coloring after forming, the technique described in Patent Document 9 is known. This document describes a method for coloring the convex portions of an embossed metal plate, and a metal is formed by an embossing die. A step of embossing a plate, a step of taking a design of the embossed metal plate and making a screen for coloring, and a metal plate processed by the embossing die using the screen made of the plate A method of coloring the convex portions of the screen by screen printing is described. Patent Document 10 describes a method of coloring a concave portion simultaneously with embossing, and describes a method of embossing a metal plate with a concave roll and coloring the embossed portion simultaneously with embossing. ing.

JP 2007-185915 A JP 2007-125684 A JP-A-5-318317 JP 2005-187925 A Japanese Patent Laid-Open No. 7-18468 JP-A-5-247353 Special table 2002-529570 gazette Japanese Patent No. 2639129 JP-A-10-202828 Japanese Patent Laid-Open No. 10-166711

  By the way, among the metal molded bodies that need to be colored, there are small or minute ones having a size of about several mm cubic or less, such as a capacitor case of an electronic device component. Since the price of such electronic device parts is extremely low due to mass production, the price cannot be significantly increased by coloring.

  However, none of the conventional coloring methods described in the above documents can meet such requirements. In particular, in the above-described electronic device parts, there are many cases where there are portions that are desired to be colored and portions that are not desired to be colored. There's a problem.

  The present invention has been made in view of the above-mentioned problems, and it is possible to color a metal molded body at a very simple and low cost, and it is easy to separate a colored portion and a non-colored portion, in particular, It is an object of the present invention to provide a coloring method suitable for coloring small or minute metal molded bodies produced in large quantities.

  In order to achieve the above object, the coloring method according to claim 1 is a method for coloring a metal molded body formed by molding a metal material, wherein a dyeable resin coating layer is formed on the surface of the metal material. Then, the metal material is molded to form a molded body having a predetermined shape, and the molded body is dipped in a dyeing agent to dye the resin coating layer.

The resin coating layer may be the entire surface of the metal material, but as described in claim 2, the resin coating layer is formed on at least a part of the surface, and the resin coating layer is formed. It is also possible to color only the part.
In this way, for example, the resin molding layer can be applied to only a part of the surface, and the metal molded body can be separately applied to two colors of the original metal color portion and the colored portion.

According to a third aspect of the present invention, the metal material is a plate material, and after the resin coating layer is formed on one of the front and back surfaces of the plate material, the surface on which the resin coating layer is formed is on the outside. Alternatively, the plate material may be stamped and / or drawn to form a metal molded body, and the metal molded body may be dipped in the dyeing agent to color the outer surface.
In this way, in a molded body such as a capacitor case, it is possible to color the outside of the case in a predetermined color and not color the inside.

  According to the present invention, it is possible to color a metal molded body at a very simple and inexpensive cost, and it is easy to separate a colored portion and a non-colored portion. In addition, after forming a resin coating layer on a metal material, a metal molded body is formed by press molding or the like and dyed and colored, so even a small lot molded body can be colored at low cost. . The present invention is particularly suitable for coloring small or minute metal molded bodies.

Hereinafter, preferred embodiments of the present invention will be described in detail.
[Metal material]
The metal material to which the method of the present invention can be applied may be any metal that can form a dyeable thermoplastic resin film, and examples thereof include steel, aluminum, titanium, stainless steel, copper, and brass. In the present invention, the metal material is preferably a plate-like material, but it can also be applied to a block-like material as long as the portion to be colored after the resin coating layer is formed is not removed by cutting.

[resin]
As the resin material to be coated on the metal material, a commercially available material can be used as long as it can be dyed.
Specifically, polyamide resins such as nylon-6, nylon-66, nylon-6 / 66 copolymer, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, and the like can be used. Moreover, polycarbonate resin, polyolefin resin, polyester resin, etc. can also be used.
In addition, since what performs press molding or drawing, for example, heats to remove internal stress after molding, a thermoplastic resin that does not melt at this heating temperature is selected.

[Formation of resin coating layer]
As a method of forming the resin coating layer on the metal material, various known methods can be used. For example, a method of attaching a resin in the form of a film or a sheet via an adhesive to the surface of the metal material, a method of melt-extruding a film-like resin on the surface of the metal material with an extruder, and the like can be mentioned.
In the case of partial coloring, a film obtained by cutting out the portion in advance may be attached to the surface of the metal material, or the resin coating layer formed on the metal material may be partially peeled off. A film-like resin may be melted and extruded on the surface of a metal material to which a release material or a mask material is attached, so that a resin coating layer is not formed on the portion, or can be easily peeled off.

[Molding]
The metal material on which the resin coating layer is formed is subjected to punching / press molding or the like to obtain a molded body having a predetermined shape.
Thereafter, in such a molding process, heat treatment may be performed to remove residual stress, and the temperature of the heat treatment is selected to be lower than the temperature at which the resin coating layer starts to melt.

[staining]
As the dye, one having excellent dyeability for the resin coating layer is selected. Examples thereof include direct dyes, acid dyes, basic dyes, mordant dyes, acid mordant dyes, sulfur dyes, sulfur vat dyes, soluble vat dyes, disperse dyes, and reactive dyes. As a method for dyeing, a method of immersing a metal molded body in a dye tank storing a dye is suitable.
The temperature and time of the dye are appropriately adjusted according to the type of dye and resin and the degree of coloring (color shade).

Although a preferred embodiment of the present invention has been described, the present invention is not limited to the above description.
For example, in the above description, punching / press molding has been described as an example. However, if the portion to be colored after the resin coating layer is not cut, cold forging or rolling may be used.

  The present invention is not limited to the field of electric / electronic devices such as capacitor cases, but can also be applied to coloring of mechanical parts and optical parts such as micro screws, pins and springs.

Claims (3)

In a coloring method of a metal molded body formed by molding a metal material,
A dyeable resin coating layer is formed on the surface of the metal material,
Molding the metal material to form a molded body of a predetermined shape,
Soaking the molded body in a dyeing agent to dye the resin coating layer;
A method of coloring a metal molded body characterized by the above. The method for coloring a metal formed body according to claim 1, wherein the resin coating layer is formed on at least a part of the surface, and coloring is performed only on a portion where the resin coating layer is formed. The metal material is a plate material, and after the resin coating layer is formed on one of the front and back surfaces of the plate material, the plate material is punched and / or drawn so that the surface on which the resin coating layer is formed is on the outside. 3. The method of coloring a metal molded body according to claim 2, wherein a metal molded body is formed by molding, and the metal molded body is dipped in the dyeing agent to color the outer surface.