| 摘要 |
In existing processes, the gold plating of the edges of contact fingers on printed circuit boards is very cost-intensive. In the case of the invention, this is avoided as a result of the fact that the printed circuit boards are coated with an etch-resistant photographic foil, and exposed, developed, etched and stripped using a pressure tool containing contact fingers and conductor pattern. Then the stop-off mask is applied while leaving the contact fingers and solder lands exposed. The contact fingers are then masked with adhesive tape and the printed circuit boards are provided with liquid resist and dried. The adhesive tape is then peeled off, the contact fingers are gold-plated and the liquid resist is stripped. The contact fingers are then masked with solder stop-off resist, and the solder lands are activated, hot-tinned and washed. The solder stop-off resist is peeled off the contact fingers and the printed circuit boards are then processed further mechanically.
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