Abstract: This invention comprises a driven conveyor for transporting work pieces into one or more flood plating cells for electroplating a metal onto the planar surfaces and surfaces of the through holes of the work piece. An electrolyte solution is pumped by one or more recirculating pumps into the flood cell at such a rate as to maintain the liquid at a desired level covering the anodes and work pieces while work pieces are moved through the cells. One or more power sources provide direct current to the anodes and to the electrified contactors to transmit electrical current to the work pieces. The electrified contactors are positioned across the path of the work piece and spaced outside of the flood cell such that the electrolyte solution does not contact the contactors. Plating will occur so long as the work piece is in contact with one or more of the electrified contactors and the electrolyte.

Abstract: A method to make volumetric additions of dilute aqueous acid solutions to a colloidal catalyst bath that will retard the salt crystallization. The process includes the steps of measuring the volumetric loss of water by physical measurements and adding dilute aqueous acid solution to the bath in the amount of the loss or by measuring the density or specific gravity of the solution and adding dilute aqueous acid solutions to maintain the specific gravity in the desired range.

Abstract: This invention is a method to extend the bath life of certain alkaline accelerators used in metal/tin colloid catalyst used in direct plating processes on printed circuit boards. The method is comprised of the following steps: measuring the pH of the alkaline activator bath, and restoring, the pH of the alkaline activator bath to a desired pH range between 12.2 and 12.6.

Abstract: This invention comprises a driven conveyor for transporting work pieces into one or more flood plating cells for electroplating a metal onto the planar surfaces and surfaces of the through holes of the work piece. An electrolyte solution is pumped by one or more recirculating pumps into the flood cell at such a rate as to maintain the liquid at a desired level covering the anodes and work pieces while work pieces are moved through the cells. One or more power sources provide direct current to the anodes and to the electrified contactors to transmit electrical current to the work pieces. The electrified contactors are positioned across the path of the work piece and spaced outside of the flood cell such that the electrolyte solution does not contact the contactors. Plating will occur so long as the work piece is in contact with one or more of the electrified contactors and the electrolyte.

Abstract: A method to remove permanent photoimagable solder mask simultaneously from the insulating laminate and conductive metal traces of a printed circuit board comprising the steps of heating a photoimagable solder mask removing solution comprised of an aqueous alkaline solution, an organic penetrating and softening agent and a tarnish and corrosion inhibitor, contacting the solution with the permanent photoimagable solder mask on the printed circuit board, allowing the permanent photoimagable solder mask to soften, and removing the photoimagable solder mask removing solution and softened permanent photoimagable solder mask simultaneously from the insulating laminate and conductive metal traces of the circuit board by rinsing the board with water.

Abstract: This invention is a process to rejuvenate the depleted metal salt oxidizing agents used in microetch cleaning compositions and to maintain the desired etch rate. This process comprises the steps of: (1) measuring the reduced metal salt oxidizing agent in the microetch cleaning composition, (2) adding a rejuvenating agent in a stoichiometric or sub-stoichiometric quantity, and (3) mixing and allowing the rejuvenating agent to react with the reduced metal salt oxidizing agent to restore the concentration of the metal salt oxidizing agent to its approximate concentration in the original microetch cleaning composition.