Abstract: In order to regenerate permanganate solutions being utilized for the etching and roughening of plastics surfaces electrolytic methods are known. Though relatively small quantaties of by-products are produced with these methods as compared to chemical regeneration methods, large quantaties of manganese dioxide are produced when printed circuit boards are treated. In order to avoid formation of manganese dioxide during the regeneration method a novel cathode 2 has been found which is provided with a porous, electrically nonconducting layer 7 on the cathode body 3. The layer 7 preferably consists of a plastics material being resistant to acid and/or alkali.

Abstract: The devices and methods of the art do not readily allow moistening of, removing gas bubbles from and/or increasing the transfer of material in through bores and/or pocket holes in printed circuit boards (PCB). Considerable problems are presented by the treatment of very narrow bores with high aspect ratios in particular. To overcome this problem a method was found that involves the following stages: the printed circuit boards PCB are passed through a processing plant on a horizontal conveying path and in one conveying plane 2 by means of transportation means 13, 14 and are thereby brought to contact a liquid for treatment, wherein mechanical pulses are directly transmitted to the printed circuit boards PCB via the transportation means 13, 14 and/or via the liquid for treatment by means of pulse generating means 50.

Abstract: In order to regenerate permanganate solutions being utilized for the etching and roughening of plastics surfaces electrolytic methods are known. Though relatively small quantaties of by-products are produced with these methods as compared to chemical regeneration methods, large quantaties of manganese dioxide are produced when printed circuit boards are treated. In order to avoid formation of manganese dioxide during the regeneration method a novel cathode 2 has been found which is provided with a porous, electrically nonconducting layer 7 on the cathode body 3. The layer 7 preferably consists of a plastics material being resistant to acid and/or alkali.

Abstract: The devices and methods of the art do not readily allow moistening of, removing gas bubbles from and/or increasing the transfer of material in through bores and/or pocket holes in printed circuit boards (PCB). Considerable problems are presented by the treatment of very narrow bores with high aspect ratios in particular. To overcome this problem a method was found that involves the following stages: the printed circuit boards PCB are passed through a processing plant on a horizontal conveying path and in one conveying plane 2 by means of transportation means 13, 14 and are thereby brought to contact a liquid for treatment, wherein mechanical pulses are directly transmitted to the printed circuit boards PCB via the transportation means 13, 14 and/or via the liquid for treatment by means of pulse generating means 50.