JPH0490338A - Method for forming protruding metal pattern, protruding metal pattern structure and metal pattern transfer sheet - Google Patents

Abstract

PURPOSE:To form a protruding metal pattern free from peeling by including a process applying electroplating to a structure obtained by bonding a metal pattern coated with a conductive adhesive to a conductive substrate and subsequently exposing the metal pattern. CONSTITUTION:A resist pattern layer 2 is formed to a conductive substrate 1 and electroplating is subsequently applied thereto form a plated metal pattern layer 3. Next, the plated metal pattern layer 3 is transferred to a weak adhesive sheet 6 (consisting of an acrylic weak adhesive layer 4 and a polyester film 5) from the conductive substrate 1. Next, a conductive adhesive is applied by screen printing so as to perfectly cover the plated metal pattern layer 3 to form a conductive adhesive layer 7. Next, a separator 8 is bonded to the weak adhesive layer 4 and the conductive adhesive layer 7 to obtain a metal pattern transfer sheet. Next, for example, the separator 8 is peeled and removed from the metal pattern transfer sheet and, after the plated metal pattern layer 3 is transferred, electroplating is applied to form a plating layer 10 to obtain a protruding metal pattern structure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for forming a convex metal pattern, a convex metal pattern structure, and a metal pattern transfer sheet. The above-mentioned convex metal pattern is provided, for example, on lighters, metal containers, and various other metal products, and serves as marking or decoration thereof. The above-mentioned convex metal pattern structure refers to, for example, lighters, metal containers, and various other metal products decorated with such convex metal patterns. Further, the metal pattern transfer sheet is used for forming the convex metal pattern.

[Prior art]

Conventionally, as a method for providing a convex metal pattern on a conductive substrate, a resist pattern layer is formed on the substrate, and then electroplating is performed to form a convex metal pattern in areas other than the resist pattern area. A plating metal pattern transfer sheet consisting of a separator (release sheet), an adhesive pattern layer, a plating metal pattern layer, and a protective sheet is used to adhere and transfer the plating metal pattern layer to the substrate. There are ways to do this.

[Problems to be Solved by the Invention] In the former method, for example, a resist pattern layer is formed on one conductive substrate, such as an intermediate product of a molded lighter, by screen printing technology or photolithography technology. This is a complicated and expensive method in which the resist pattern layer is removed after forming and electroplating. Furthermore, since a resist pattern layer cannot be formed on the curved surface of the substrate, there is also a drawback that convex metal notches cannot be formed on the curved surface.

On the other hand, the latter method had the disadvantage that it was easy to peel off because the rough metal layer was simply stuck on the conductive substrate with an adhesive.

The present invention was made to solve the above-mentioned drawbacks of the prior art, and provides a method for forming a convex metal pattern that can be formed even on the curved surface of a conductive substrate and does not cause peeling. The main purpose is to Another object of the present invention is to provide a convex metal no-turn structure in which the convex metal pattern does not peel off from the conductive substrate. A further object of the present invention is to provide a metal pattern transfer sheet that can be used in the above method.

[Means for solving problems]

According to the present invention, the present invention is characterized by including a first step of pasting a metal pattern with a conductive adhesive on a conductive substrate, and a second step of performing electroplating on the structure obtained in the first step. A method for forming a convex metal pattern is provided.

Further, according to the present invention, a plating layer is formed that covers at least the side wall of the conductive adhesive layer of the structure having the metal pattern layer provided on the conductive substrate via the conductive adhesive layer. A convex metal pattern structure is also provided.

Furthermore, according to the present invention, a protective film is provided which sequentially includes a conductive adhesive pattern layer, a metal pattern layer provided substantially on the conductive adhesive pattern layer, and a weak adhesive layer. Also provided is a metal pattern transfer sheet comprising: Preferably, the metal pattern transfer sheet is provided with a separator (H release sheet) on the adhesive side to facilitate handling and storage.

[Effect]

According to the method for forming a convex metal pattern of the present invention, a metal pattern with a conductive adhesive is pasted on a conductive substrate, and then electroplating is performed. Since the plated metal layer is also formed on the side wall of the adhesive layer, there is no starting point for such peeling, and the convex metal pattern layer does not peel off. This is because the adhesive layer is made conductive so that electroplating can be performed, so that it is plated not only on the metal pattern but also on the sidewalls of the adhesive layer. Further, since the method of the present invention can be carried out by simply applying a metal pattern to a substrate and electroplating it using a metal pattern transfer sheet, productivity can be improved. Furthermore, by selecting the thickness of the conductive adhesive layer plus the metal pattern layer, the thickness of the convex metal pattern layer can be freely set, and the plating time can be shortened, so that production costs can also be reduced.

The present invention will be explained in detail below.

Examples of the conductive substrate include plates made of various metals and conductive ceramics, and intermediate products made of the above-mentioned materials formed into the shape of lighters, containers, and the like. Examples of such metal materials include aluminum, chromium, nickel, copper, gold, silver, tin, alloys thereof, stainless steel, etc., and examples of conductive ceramic materials include ceramic materials themselves such as silicon carbide and molybdenum silicide. Ceramic substrates manufactured by firing or sintering conductive materials, metal powders, carbon black, graphite powders, conductive metal oxide powders, etc., are uniformly dispersed in ceramic materials and fired or sintered. ITO
Examples include a transparent conductive substrate such as (indium tin oxide), a substrate having such a transparent conductive film, and the like.

As the conductive adhesive, one prepared by uniformly dispersing conductive powder in a rubber-based, acrylic-based, or silicone-based adhesive can be used. Examples of such conductive powders include powders of metals and alloys such as copper, silver, gold, tin, zinc, iron, stainless steel, aluminum, and nickel, graphite powder, carbon black, and conductive metal oxide powders. be able to. In addition, even if the above adhesive is a non-crosslinked type,
Although a crosslinked type adhesive may be used, the latter type is preferred, and an acrylic adhesive is preferred. The thickness of the conductive adhesive layer is
Although not particularly limited, 5 to 60 microns is preferred, and 10 to 30 microns is more preferred.

As the metal material for the metal pattern (layer), copper, gold, silver, nickel, chromium, tin, and other various metals and alloys can be used. The thickness of the metal pattern layer is not particularly limited, but is preferably 1 to 100 microns. The thickness of this metal pattern layer is relatively large because it will be electroplated later on and the thickness of the convex metal pattern layer formed by electroplating can also be increased by the thickness of the conductive adhesive layer. It can be small.

As the metal material for electroplating performed in the second step, the same metal materials as those for the metal pattern (layer) described above can be used. The thickness of the plating layer formed by this electroplating is also not particularly limited, but is preferably 1 to 100 microns. The metal material of the metal pattern (layer) and the metal material of the second electroplating step may be the same or different. If different metal materials are used for the two, for example, if gold is used for the metal pattern and nickel is used for the second electroplating process, then after the second process, for example, buffing (preferably By polishing and removing the upper part of the convex metal pattern (parallel polishing), the original metal pattern is exposed and only this area becomes gold, creating a strong contrast with the metal color of the nickel background. , further decorative effects can be achieved.

In carrying out the method for forming a convex metal pattern of the present invention, for example, in this order, a separator, a conductive adhesive pattern layer, and a metal pattern layer provided so as to be substantially located on the conductive adhesive pattern layer , and a protective film having a weak adhesive layer can be used. When the separator of the metal pattern transfer sheet is peeled off, the conductive adhesive pattern layer is adhered to the surface of the conductive substrate, and the protective film is peeled off, the metal pattern layer is transferred. When electroplating is performed on the conductive substrate with a metal pattern obtained in this way, not only the exposed surface of the substrate is plated, but also the surface of the metal pattern layer is plated because current flows through the conductive adhesive pattern layer. It is plated on top and on its sidewalls as well as on the sidewalls of the conductive adhesive pattern layer. In this way, a convex metal pattern is formed on the conductive substrate.

The weak adhesive layer in the protective sheet of the metal pattern transfer sheet that can be used in this way includes non-crosslinked or crosslinked rubber-based, acrylic-based, and silicone-based adhesives.
A cross-linked acrylic type is preferred. The thickness of the weak adhesive layer is not particularly limited, but is preferably 3 to 30 microns, more preferably 5 to 20 microns.

Further, as the film layer of the protective film, various relatively thin plastic films of about 5 to 20 microns can be used, but polyester films and polypropylene films are preferred. As the separator, ordinary release paper or release film can be used.

〔Example〕

Hereinafter, the present invention will be specifically explained from Example 1 with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to this example. It should be noted that each figure is merely for explaining the principle content of the present invention, and therefore,
The dimensions, shapes, etc. of each component shown in the drawings do not represent actual dimensions, shapes, etc.

Example 1 An example of the method for manufacturing a metal pattern transfer sheet of the present invention will be described with reference to FIGS. 1(a) to 1g).

First, the surface of a conductive substrate 10 such as a stainless steel foil as shown in FIG. For example, by treating with chromic acid or orthochromic acid,
Surface treatment that produces conductive chromate,
To enable easy and reliable peeling from the plated metal layer that will be formed later by electric polishing (surface treatment is especially necessary if peeling or surface treatment can be easily performed without such surface treatment). However, processing V is not illustrated.

Next, a plating resist is printed and applied onto the conductive substrate 1 by screen printing to form a resist pattern layer 2 as shown in FIG. 1(b). Instead of screen printing, the resist pattern layer can also be formed using photolithography technology, and in this case, it is possible to form a finer resist pattern.

Next, when the ifR structure of FIG. 1(b) thus obtained is electroplated with, for example, nickel, a plated metal pattern layer 3 is formed, and the structure of FIG. 1(c) is formed. is obtained. After that 1. When the resist pattern layer 2 is removed from the second structure by a conventional method, the structure shown in FIG. 1(d) is obtained.

Next, as shown in FIG. 1(e), the plated metal pattern layer 3 is coated from the conductive substrate 1 with a weak adhesive sheet 6 (for example, a sheet consisting of an acrylic weak adhesive layer 4 and a polyester film 5). (The plated metal pattern layer 3 adhering to the weak adhesive layer 4 is easily peeled off from the substrate 1.).

Next, for example, an acrylic conductive adhesive with conductivity imparted by uniformly dispersing nickel powder is screen printed so as to completely cover the plated metal pattern layer 3, and the structure shown in FIG. 1(f) is formed. Get a body. At this time, as shown in FIG. 1(f), the conductive adhesive layer 7 may be printed so as to slightly protrude from the area of the plated metal pattern layer 3 in order to provide margin for alignment, as will be described later. This will not cause any problems. Note that although FIG. 1(f) is illustrated as if it were printed from the bottom in order to make it easier to understand in comparison with the previous figures, it goes without saying that it is actually printed from the top.

Next, as shown in FIG. 1(g), if necessary, a separator 8 is placed over the weak adhesive layer 4 and the conductive adhesive layer 7.
Paste the metal pattern to get a transfer sheet. This attachment of the separator 8 is not necessary if the step immediately proceeds from this step to the step of transferring the metal pattern on the conductive substrate 9 of Example 2.

Figure 1 (h) is the figure 1 (g) obtained in this way.
FIG. 2 is a perspective view of an example of the remaining structure that would be observed if the protective sheet 6 were removed from the metal pattern transfer sheet of FIG.

Such a metal pattern transfer sheet may be manufactured using an etching method instead of an electroplating method.

Example 2 A conductive substrate 9 made of copper, such as a plate or an intermediate product formed into the shape of a lighter, container, etc. (degreased, polished, washed with water, pickled, and other pre-treatments are performed as necessary) .

), the separator 8 is peeled off and removed from the metal pattern transfer sheet shown in FIG. 1(g) produced in Example 1, and the plated metal pattern layer 3 is transferred thereon. At this time, the part of the conductive adhesive layer 7 that protrudes beyond the area of the plated metal pattern layer 3 is adhered to the weak adhesive layer 4, so it is peeled off together with the protective film 6, and the plated metal pattern layer 7 is peeled off together with the protective film 6. Only the conductive adhesive layer 7 in the area corresponding to 3 remains on the conductive substrate 9 together with the plated metal pattern layer 3 [Fig. 2 (a)
)reference〕.

Next, the entire surface of the thus obtained structure shown in FIG. 2(a) is electroplated with, for example, nickel to form a plating layer 10, and the convex metal pattern shown in FIG. 2(b) is formed. Get the struct. In this way, a convex metal pattern can be easily formed on the conductive substrate 9.

Example 3 Metal pattern layer 3 of the metal pattern transfer sheet of Example 1
A similar metal pattern transfer sheet is manufactured using gold instead of the nickel used in .

Using this metal pattern transfer sheet, a convex metal pattern is formed on the conductive substrate 9 in the same manner as in Example 2.

Next, the thus obtained structure shown in FIG. 2(b) is subjected to buff polishing (for example, parallel polishing), and the upper part of the convex metal pattern is polished and removed. The metal pattern layer 3 is exposed to obtain the convex metal pattern structure shown in FIG. 2(c). In this way, the gold color of the metal pattern layer 3 contrasts with the nickel metal color of the plating layer 10 in other parts, resulting in a beautiful decoration.

Although the present invention has been specifically explained above with reference to Examples, the present invention is not limited to the above-mentioned Examples.
It goes without saying that various modifications and alterations can be made within the scope of the present invention. For example, the method for forming a convex metal pattern of the present invention and the electroplating method using a plating-resistant adhesive tape can be combined. In this case, three-dimensional decoration can be provided in three stages: the exposed portion of the conductive substrate, the convex metal pattern portion, and the other plated portion located at an intermediate height between the two. Further, by using the metal pattern transfer sheet of the present invention, a metal pattern can be transferred over the curved surface of a conductive substrate, and a convex metal pattern on the curved surface can be formed by the method of the present invention.

Furthermore, by following the procedure of Example 1, it is also possible to create a transfer sheet of a series of separated metal patterns, such as a series of letters, and if the method of the present invention is carried out using such a metal pattern transfer sheet, , it is possible to form discrete convex metal patterns on a conductive substrate while maintaining the positional relationship of each metal pattern.

〔effect〕

According to the method for forming a convex metal pattern of the present invention, a convex metal pattern layer that does not peel off can be easily formed on a conductive substrate at low cost. In the second step of electroplating in the method of the present invention, a plating layer is formed on the sidewall of the conductive adhesive layer as well as on the metal pattern, so that the convex metal pattern layer does not peel off. Moreover, since the conductive adhesive layer is not exposed, the aesthetic appearance is not impaired. Metal pattern transfer sheets can be mass-produced, so productivity can be improved by attaching metal patterns to conductive substrates and electroplating them, and forming a conductive adhesive layer plus a metal pattern layer. By selecting the thickness as desired, the thickness of the convex metal pattern layer can be freely set, and the plating time can also be shortened.

[Brief explanation of the drawing]

FIGS. 1(a) to 1(g) are schematic cross-sectional views of each structure created in the main steps of the method for manufacturing an example of a metal pattern transfer sheet of the present invention, and FIG. This corresponds to a horizontal cross section near the vertical center of the perspective view. FIG. 1(h) is a schematic diagram of an example of the remaining structure that would be observed if the protective sheet 6 were removed from the structure of FIG. 1(g), that is, the metal pattern transfer sheet. FIG. FIGS. 2(a) to 2C) are schematic cross-sections of each structure obtained in each step of forming a convex metal pattern on a conductive substrate according to an example of the method for forming a convex metal pattern of the present invention. 2(a) and 2(b) illustrate the method of the second embodiment, and FIG. 2(C) illustrates the method of the third embodiment. DESCRIPTION OF SYMBOLS 1... Conductive substrate, 2... Resist pattern layer, 3... Plated metal pattern layer, 6... Weak adhesive sheet (protective film), 7... Conductive adhesive layer, 8...・Separator 9... Conductive substrate, lO... Plated layer. (a) Ro=Nigo Nikaku-1-- Patent applicant: Nakazawa Sculpture Co., Ltd. Patent applicant: Cosmotec Co., Ltd.

Claims (1)

[Claims] 1. Includes a first step of pasting a metal pattern with a conductive adhesive on a conductive substrate, and a second step of electroplating on the structure obtained in the first step. A method for forming a convex metal pattern characterized by: 2. Buffing the structure obtained in the second step,
The method for forming a convex metal pattern according to claim 1, further comprising the step of exposing the metal pattern. 3. A convex structure having a metal pattern layer provided on a conductive substrate via a conductive adhesive layer, wherein a plating layer is formed to cover at least the side wall of the conductive adhesive layer. shaped metal pattern structure. 4. A protective film including, in order, a conductive adhesive pattern layer, a metal pattern layer provided substantially on the conductive adhesive pattern layer, and a weak adhesive layer. Metal pattern transfer sheet. 5. Claim 4, characterized in that a separator is provided on the side of the conductive adhesive pattern layer opposite to the metal pattern layer and on a part of the weak adhesive layer.
Metal pattern transfer sheet as described in section.