JPS6160899A - Plating method of surface copper foil of printed board - Google Patents

Abstract

PURPOSE:To reduce the size of a plating cell and to diminish the installation area of the plating cell in electroplating of copper to the copper foil on the surface of a printed board by forming an anode of a belt-like body and moving said anode so as to cover the metallic surface to be plated. CONSTITUTION:Rails 8 supported horizontally to the plating cell 1 are formed to the length larger than the length on the other side of the printed board 3 to be plated. A driving part 7 is imposed on said rails. The part 7 is made movable on the rails 8 by a driving source and the anode 5 of the copper which is the belt-like body is attached to the part 7. The part 7 is positioned toward the left end and the board 3 is supported horizontally. The anode 5 is the belt- like body made to about 1cm width and therefore the area occupied by the cell 1 for the purpose of the anode 5 is small. While electrolytic current is conducted to the anode 5 together with the board 3, the anode 5 is moved back and forth on the rails 8, by which the copper is electrolytically plated to the copper foil 4 surface of the board 3.

Description

Detailed Description of the Invention (11) Technical Field of the Invention The present invention relates to electrolytic plating of copper to copper foil on the surface of a printed circuit board, and in particular to plating of copper to increase the adhesive strength between the copper foil and the resin layer to be laminated. Concerning coarsening and 7ki.

(2) Background of the technology In order to increase the adhesive strength between the resin layer and the printed circuit board that adheres the printed circuit boards to be laminated, and to prevent delamination and void generation, copper is added to the copper foil on the adhesive surface of the printed circuit board. Electrolytic plating does not cause the copper foil surface to become rough, increasing the total area of bonding with the resin and providing the necessary adhesive force between the eyebrows due to the anchoring effect.

(3) Prior Art and Problems FIG. 1 shows a conventional method of electrolytically plating copper onto copper foil on the surface of a printed circuit board, and FIG. 2 shows a method of electrolytic plating with the printed board held horizontally.

1 is a plating bath, 2 is an electrolyte, and 3 is a printed circuit board.

4 represents a copper foil, 5 represents an anode, and 6 represents a power source.

The conventional copper electrolytic plating method for roughening the copper foil of printed circuit boards is as shown in Figure 1. The printed circuit board 3 to be plated and the anode 5 are vertically suspended in an electrolytic solution 2 filled with 1! dm”
Overcurrent plating is performed by applying a current of about 10 A for about 1 minute per plating to obtain copper needles of about 10 μm. However, since the copper needles in step 2 grow in the direction of gravity, the entire surface of the copper foil 4 Because it is not possible to obtain a uniformly roughened surface to increase adhesive strength,
Copper foil 4 of printed circuit board 3 to be plated as shown in FIG.
is held horizontally in electrolytic solution 2, and copper foil 4 is electrolytically plated.
The resulting copper needles are generated perpendicularly to the copper foil 4 to obtain a uniformly roughened surface.

The electrolytic plating of the copper foil 4 on both sides of the printed circuit board 3 allows the printed circuit board 3 to be held horizontally between two anodes 5 supported at a distance in the electrolytic solution 2.

The anode 5 generally has approximately the same dimensions as the printed circuit board 3, and when the printed circuit board 3 is inserted between the two fixed anodes 5, the printed circuit board 3 is placed approximately horizontally at the outside of the insertion end into the anode 5. and move it to a desired position between the anodes 5.

Therefore, at least the size of the plating tank 1 is such that the anode 5 and the printed circuit board 3 can be placed together.
The shape of the device is large and the corresponding installation has the disadvantage of requiring a large area.

(4) Purpose of the Invention In view of the above-mentioned drawbacks of the conventional art, the object of the present invention is to provide a method that can minimize the size of the metal plating bath when performing electrolytic plating with the copper foil of a printed circuit board horizontal. It is something.

(5) Structure and object of the invention According to the present invention, there is provided a method for plating copper foil on the surface of a printed circuit board, which is characterized in that the anode is formed into a strip and is moved so as to cover the entire surface of the printed circuit board to be plated. This is achieved by providing

(6) Examples of the invention Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 3 is a side view showing an electrolytic plating apparatus for copper foil on the surface of a printed circuit board manufactured by Kinoe and Akira, and FIG. 4 is a plan view of FIG. 3.

In the figure, 7 indicates a drive section, and 8 indicates a rail.

The method of electrolytic copper plating of copper foil on both surfaces of a printed circuit board according to the present invention is as shown in FIGS. 3 and 4.

The rail 8 is immersed in the drive part 7 in the electrolyte 2 of the plating bath 1.

The rails 8 are composed of at least a pair of left and right sides, and are supported horizontally in the plating tank 1, the length of the rails 8 is larger than the length of the other sides of the printed circuit board 3 to be plated, and the drive unit 7
The drive unit 7 can be easily moved on the rail 8 by a drive source, and the band-shaped copper anode 5 is attached to the drive unit 7.

The anode 5 and printed circuit board 3 are connected to a power source 6.

According to this device, the drive unit 7 is positioned at the A end shown in the figure, the printed circuit board 3 is supported horizontally, and the anode 5 has a width of about 1
Since it is a c+n band, the area occupied by the plating bath l for the anode 5 is small. Holds the printed circuit board 3,
The anode 5 is reciprocated on the rail 8 by the drive unit 7 while being energized together with the anode 5, and the copper foil 4 of the printed circuit board 3
The surface is electrolytically plated with copper.

(7) Effects of the Invention As explained in detail above, according to the method of plating copper foil on the surface of a printed circuit board of the present invention, the dimensions of the plating bath can be reduced by the length corresponding to the moving distance of the anode, which is considerably The installation iiom can also be made smaller.

In addition, it is possible to control the growth of plating by curving the rail relative to the printed circuit board and changing the distance between the printed circuit board and the anode, which has great effects in downsizing the plating bath and controlling plating.

[Brief explanation of drawings]

FIG. 1 shows a conventional method for electrolytically plating copper onto copper foil on the surface of a printed circuit board, and FIG. 2 shows a method for electrolytic plating with the printed circuit board held horizontally. FIG. 3 is a side view showing an electrolytic plating apparatus for copper foil on the surface of a printed circuit board according to the present invention, and FIG. 4 is a plan view of FIG. 3. In the figure, 3 is a printed circuit board, 4 is a copper foil, 5 is an anode, 7 is a drive section, and 8 is a rail.

Claims (1)

[Claims] The anode is made into a strip that faces the metal surface to be plated.
A method for plating copper foil on the surface of a printed circuit board, characterized by moving the copper foil so as to cover the surface to be plated.