JPH058580B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of forming a lead frame pattern by etching.

[Prior Art] Conventionally, when manufacturing a lead frame pattern by etching, a method has been adopted in which resist ink is applied to the entire surface of the metal foil except for the portion 2 to be opened, as shown in FIG. 4, and then the resist ink is immersed in an etching solution. It was getting worse.

[Problems to be Solved by the Invention] However, this conventional technique is an extremely uneconomical and energy-consuming method in which 100% of the portion of an expensive metal material to be opened is removed by a melting method.

SUMMARY OF THE INVENTION It is an object of the present invention to overcome the drawbacks of the prior art described above and to form a lead frame pattern in an economical and energy-saving manner using etching-cutting technology.

[Means for Solving the Problems] The gist of the present invention is to (a) coat the entire surface except for the boundary between the portion to be removed by etching and the portion to be left by resist printing; ) Next, this is immersed in an etching solution to dissolve and remove only the uncoated boundary portion, and (c) finally, the cut piece is removed by ultrasonic vibration, jet water flow, shaking, etc. It consists in forming a pattern.

[Examples] The present invention will be explained in more detail below using Examples.

A thick copper plate with a width of 45 mm and a length of 205 mm was prepared, and the entire surface of the plate was printed with resist, leaving only a small portion of the border between the portion to be etched and the pattern portion, and the other portions were printed with resist. This will be explained based on FIG. 1: 4 is a resist ink coated portion, 2 is a portion that will become an opening, and 3 is a portion to which resist ink is not applied. The size of the frame is 40 mm in width, 200 mm in length, and 0.25 mm in thickness, and the size of the square pattern is 5.7 mm square. Further, the width of the portion 3 to which the resist ink is not applied is only 0.2 mm, and only this portion comes into contact with the etching chemical solution. The copper plate 1 is etched from both sides of the portion 3 to which the resist ink is not applied, and when the opening portion is completely separated, the cross section will be approximately as shown in FIG. 2. As the etching progresses further, the cross section shown in the figure is completely penetrated from side to side, but in a natural state, the cut pieces at the openings do not fall. FIG. 3 is a cross-sectional view of the etching apparatus used in this embodiment, and the cut pieces at the openings that have been etched fall due to the propagation of vibrational energy from the ultrasonic vibrator 6. In this embodiment, ultrasonic vibration is used as a means for dropping the cut pieces, but means such as jet water flow or swinging of the frame 7 may also be used. Reference numeral 9 denotes a conveyor for transporting the fallen cut pieces outside the tank, and the cut pieces are continuously fed into the storage tank 14.
A washing water supply pipe 11 is connected to the storage tank 14, and the cut pieces fed therein are continuously washed with water.

[Effects of the Invention] As explained above, according to the present invention, only the boundary between the part of the metal foil to be opened and the part to be left comes into contact with the etching solution, so the amount of etching solution used can be reduced, which is different from the conventional etching solution. As a result, the cost of processing the aging etching solution can be reduced, and cut pieces can be collected more effectively.

[Brief explanation of the drawing]

Figures 1 to 3 are explanatory diagrams showing an embodiment of the present invention. Figure 1 is a plan view showing a state in which resist ink has been applied to a copper plate, and Figure 2 is a plan view showing the state in which the opening portion has been completely separated by etching. Fig. 3 is a sectional view of the etching device;
The figure is a plan view showing a conventional example. DESCRIPTION OF SYMBOLS 1... Copper plate, 2... Portion to be opened, 3... Portion without resist ink, 4... Portion coated with resist ink, 5... Etching tank, 6... Ultrasonic vibrator, 7...
Frame, 8...conveyor roller, 9...conveyor,
10... Etching liquid, 11... Washing water supply pipe,
12...Washing water, 13...Overflow tank, 14...
Storage tank, 15...Washing water outlet.

Claims (1)

[Claims] 1. (a) Coating the entire surface by resist printing except for the boundary between the part to be removed by etching and the part to be left; (b) immersing this in an etching solution to coat the uncoated boundary part. a step of dissolving and removing only the
A method for forming a lead frame pattern by etching, comprising a step of removing cut pieces by ultrasonic vibration, jet water flow, rocking, etc.