JPS62112793A - Method for plating electronic parts at high speed - Google Patents

Abstract

PURPOSE:To accelerate the plating of electronic parts by placing the parts between insoluble electrodes in an electrolytic soln., electrifying the electrodes as the anode and the parts to be plated as the cathode and supplying a high electric current to the electrodes. CONSTITUTION:A hoop (a) of phosphor bronze or the like to be plated is put in a cell (c), insoluble electrodes (b) and the hoop (a) are electrified as the anode and cathode, respectively, and a high electric current is supplied to the electrodes to carry out Watts bath nickel plating or other plating. By this method, stirring action is caused by bubbles generated from the electrodes (b), so plating is accelerated, the occurrence of unevenness in a plated layer is prevented and plating can be stabilized.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method of continuously plating long cable materials such as lead frames and connectors, and mainly relates to a method of performing base plating at high current density. Ruchino.

(Prior art and its problems) At present, lead frames, connectors, etc. are made of copper, copper alloys, IS, and iron alloys, and are made of flat plates or pressed caps. Method iiO treatment step.

It is manufactured by continuously performing the base plating process and the final precious metal plating process.

Recently, there has been a desire to increase the line speed of reel-to-reel systems, and to this end, it is conceivable to increase the length of the plating tank in the plating step, which takes the longest processing time, in proportion to the line speed.

In addition, in the final circular metal plating process, partial plating is increasingly used to reduce costs, making it possible to increase the line speed several times even with a plating bath of the same length as before. It is difficult to increase the speed when performing full-surface plating on a substrate such as nickel plating, and furthermore, when the plating tank cannot be made long due to factory space constraints, this becomes an obstacle to increasing the line speed.

Furthermore, as high-speed plating methods, the forced flow method in which the plating solution is forced to flow with a pump, impeller, etc., the cathode rotation method, the vibration method, and the 12 scraping method have been proposed.
Currently, there is no practical example of the flow method other than its application to precious metal plating.

When this forced flow method is applied to the entire surface plating of copper, nickel, etc. substrates, it is necessary to supply several hundred liters of plating solution per minute, which requires a huge pump, which causes large noise and vibrations, and also requires a large space for plating. There were problems such as the need for a wide range of

Furthermore, this method has drawbacks such as difficulty in uniformly stirring the entire product, resulting in uneven appearance.

Furthermore, since there is a conventional method that allows a low current to flow through a soluble anode, it is possible to apply this to flow a high current in place of the low current moss.

However, in this case, the number of iJ-soluble 7 nodes melted increased, and the number of bubbles was small.

(Technical Problem to be Solved by the Invention) A technical problem to be solved by the present invention is to solve the above-mentioned problems by electrolysis in a conventional plating bath when plating long materials such as lead frames and connectors. The aim is to increase the stirring effect by generating air bubbles in the liquid, thereby increasing the speed and stabilization of plating.

(Technical Means for Achieving the Technical Problem) The technical means of the present invention for achieving the above-mentioned technical problem is to vertically arrange insoluble anodes facing the electrolytic solution at appropriate intervals, and Placing the object to be plated between insoluble anodes, charging the insoluble anode as an anode and the object to be plated as a cathode, and applying a high current to the anode to generate bubbles in the electrolyte to perform plating. It is.

(Effects of the Invention) The present invention has the following effects by having the above configuration.

■ An insoluble anode is used, and the air bubbles generated from the anode surface create a stirring effect, which speeds up plating, and the electrically insulating air bubbles between the electrodes suppress the tip current, resulting in faster plating. It is possible to prevent variations in thickness and stabilize the plating.

■ By arranging the insoluble 7 nodes in an I-shape, the air bubbles generated from the insoluble anode will not be blocked in any way and will rise, so the plating will be effective and stable on the object to be plated. It is done.

■ Since it is possible to speed up plating in a normal plating tank without purchasing special equipment or enlarging the plating tank, costs can be reduced.

(Example) As shown in the figure, an example of the present invention is a phosphor bronze hoop (a).
After pre-treatment such as degreasing and pickling, the effective length is 50 (
1 mm in the plating cell according to the invention (C) at a feed rate of 6
m/min and a conventional Watt bath nickel plating test was carried out.

(b) is an insoluble anode.

Table 1 below shows the results.

Table 1: Appearance after plating Comparative Example 1 in this table is the one in which nickel plating was performed using the conventional overflow method, and Comparative Example 2
A nickel plating test was conducted by supplying a plating solution at a rate of 0.5/min during plating in Comparative Example-1.

Table 2 shows the plating thickness distribution in the width direction of phosphor bronze hoops subjected to cathodic flow-tight nickel plating at 100 A/dTIt for 5 seconds using the method of Example and Comparative Example-2.

Table 2 Distribution of plating thickness Note that measurement positions A and C are 1Nn from the edge of the object to be plated, and B is the center.

Therefore, as is clear from the table above, the above effects can be achieved, namely, speeding up plating, stabilizing and improving plating efficiency by preventing plating variations, and reducing costs. I was able to confirm.

BRIEF DESCRIPTION OF THE DRAWINGS The figure is a longitudinal sectional view of a plating tank showing the plating method of the present invention. In the figure, (a) shows an object to be plated, and (b) shows an insoluble anode.

Claims (1)

[Claims] Insoluble anodes facing the electrolytic solution with an appropriate interval are arranged vertically, and an object to be plated is arranged between these insoluble anodes, and the insoluble anode is charged as an anode and the object to be plated is charged as a cathode. A high-speed plating method for electronic components that generates bubbles in the electrolyte by passing a high current through the anode.