JPS61227197A - Plating method - Google Patents

Abstract

PURPOSE:To form plating layers having a uniform thickness on cathodes having different shapes and sizes by dipping and dispersing alternately plural anode plates and the cathode plates to be plated into a plating liquid vessel and passing adequate electric currents from separate power sources to the respective cathode plates. CONSTITUTION:The plural anodes 3a, 3b, 3c are dipped into the plating liquid 2 in the plating vessel 1 and are connected by conductors 6 to positive terminals 8 of two external electric power sources. The cathodes 4a, 4b having the different shapes and sizes as the material to be plated are dipped between the anodes 3a, 3b, 3c and electricity is conducted thereto to form the plating layers on the surface. The cathodes 4a, 4b of the material to be plated are connected to negative terminals 7 of the separate power sources 5, 5 and the currents meeting the area of the cathodes 4a, 4b are conducted to the cathodes to regulate the current densities of the respective cathodes to the same density, by which the plating layers having the uniform film thickness are formed on both materials 4a, 4b to be plated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a plating method that improves the method of connecting an external power source used for plating to a cathode and an anode.

[Technical background of the invention and its problems]

Conventionally, metal plating includes, for example, silver, copper, nickel, gold, and zinc plating. Taking silver plating as an example, there is a step in which silver is deposited and deposited on a member during the silver plating process. In this process, the method of connecting the external power source, cathode, and anode is to connect the two or more cathodes in parallel, connect the two or more anodes in parallel, and perform plating with one external power source. .

In the above method, for example, when plating members with different surface areas connected to the cathode, the current concentrates on the member with a small surface area, resulting in a thicker plating film than specified, and conversely, the current concentrates on the member with a large surface area. As a result, the plating film thickness is thinner than the predetermined value, and the variation in the plating film thickness is, for example, the standard deviation σ=17.
It was 4. For this reason, those used for the fitting part had a problem because it required work to remove excess silver.

In addition, when a member that has reached a predetermined plating thickness is pulled out of the plating solution and the remaining members are subsequently plated, the predetermined film thickness will be obtained by the time the initially set time is reached, so the amount of current applied to the pulled-up member will be I needed to save time.

When the time required to pull up the member from the plating solution is different, the work is very complicated as the work must be done at predetermined intervals.

[Purpose of the invention]

The present invention has been made to eliminate the above-mentioned drawbacks, and aims to provide a plating method that eliminates concentration of current, obtains a predetermined plating film thickness in a predetermined time, and reduces variations in the plating film thickness. This is the purpose.

[Summary of the invention]

In order to achieve the above object, according to the present invention, a metal plating solution is placed in an electrolytic bath, and an anode made of a metal to be plated or stainless steel and carbon and a cathode made of a member to be plated are oriented toward each other in the metal plating solution. The cathodes are immersed so that they match, an external power source is connected to each of the cathodes, and plating is performed, thereby obtaining a predetermined plating film thickness.
This allows for less variation.

[Embodiments of the invention]

An embodiment of the present invention will be described with reference to the drawings.

In this embodiment, metal plating such as silver, copper, nickel, gold and zinc plating is used, and of these, silver plating will be explained as an example. Inside the electrolytic cell 1 whose top is open in the figure, anode plates 3a, 3b each made of a silver plate,
3c and cathode plates 4a and 4b consisting of members to be plated are hung and attached so as to alternately face each other. The anode plate 3a is connected to other anode plates 3b and 3c by a conductor 6, and the conductor 6 is connected to two external power sources 5.
are connected to the positive terminals 8 of the respective terminals. On the other hand, cathode plate 4
a is directly connected to one external power source 5 by a conducting wire, and the other cathode plate 4b is connected to the negative terminal 7 of the other external power source 5, respectively.

An electrolytic cell 1 is filled with a silver plating solution 2 containing a cyanide compound containing silver ions. A circulation device 9 for stirring this plating solution is provided, and the structure is similar to that of ordinary electroplating.

Next, the effects of the present invention configured as described above will be explained. Since the two external power supplies 5 supply current according to the surface area of each member to be plated placed on the cathode, the concentration of current is alleviated, and the plating film does not become thicker than a predetermined thickness. For example, when 50JJIIt has a standard deviation of σ=4.06 with respect to the target plating film thickness, the variation is small, and plating can be performed with high accuracy to the set film thickness. Therefore, for those used in the fitting portion, there is an advantage of eliminating the need to remove excess silver.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to provide a plating method that can obtain a plating film thickness with less error relative to a target plating film thickness.

[Brief explanation of the drawing]

The figure is a schematic configuration diagram without showing the plating method of the present invention.

Claims (1)

[Claims] A plurality of anode plates and a cathode plate of a member to be plated are alternately immersed and arranged so as to face each other in an electrolytic bath filled with a metal plating solution, and the anode plates are connected to a plurality of external power sources. and each cathode plate is connected to the external power source capable of supplying current according to the surface area of the cathode plate.