| 摘要 |
Dielectric articles, such as printed circuit panels, to be chemically plated are first immersed in at least one conditioning bath wherein compressional waves of frequency exceeding 20 kc/s. and preferably less than 400 kc/s., are maintained, and then coated with a metal, e.g. silver, nickel, or copper, by immersion in a plating bath. For a silver coating, the article is immersed in a sensitizing bath consisting of an aqueous solution of a metallic salt such as stannous chloride. For a nickel coating, an activating bath consisting of an aqueous solution of a slat of a noble metal such as palladium or gold chloride is used. Hydrochloric acid may be added to the above solutions. For a copper coating, both a sensitizing and an activating bath is used, prior to immersing the article in a copper plating solution, e.g. containing copper sulphate, sodium potassium tartrate, NaOH and formalin. To provide electrical interconnections between two electrical circuit conductive patterns located upon opposite sides of an epoxy glass printed circuit panel, the panel is covered with a protective material such as lacquer and perforated at those points where electrical interconnections are required. The panel is then successively immersed in the above conditioning baths, washed, and then immersed in the above copper-plating solution. Additional copper may be deposited by electroplating. |
