Abstract: The present invention relates to an apparatus and a process for regenerating a used etchant solution, which solution contains a metal in divalent form. The apparatus includes a tank which is originally supplied with the etchant solution; a first electrolytic cell for converting solution from the tank to a solution containing a high fraction of a monovalent form of the metal; and a second electrolytic tank for plating metal from the solution containing a high fraction of the monovalent form of the metal. The details of the process of the present invention are set forth in the disclosure.

Abstract: A process and apparatus for producing metal foil comprises supplying an isotopically polished continuous cathode, a high volume turbulent flow of electrolyte and rigorous filtration to exclude chlorides, sulfides, organics and other impurities from the electrolyte. The foil so produced is free from micro-voids and able to withstand substantially higher biaxial stresses than conventional electrodeposited foil. The micro void free structure also decreases the diffusion rate of an underlying substrate.

Abstract: The present invention relates to a system and a process for producing improved quality electrodeposited and/or treated metal or metal alloy foil to be used in electrical and electronic applications. The quality of the foil being produced and/or treated by the system is improved by providing each treatment tank in the system with a dual filtration system. The dual filtration system for each tank comprises a filter conditioning loop for substantially continuously withdrawing solution from the tank and removing particulate matter from the withdrawn solution and a system for removing surface impurities from the solution. In a first embodiment, the surface impurities removing system comprises an off-line solution filtration and replenishment system. In a second embodiment, the surface impurities removing system comprises a skimmer floating on the surface of the solution. The present invention has particular utility in systems for producing electrodeposited and/or treated copper foils.

Abstract: The present invention relates to a system and a process for producing improved quality electrodeposited and/or treated metal or metal alloy foil to be used in electrical and electronic applications. The quality of the foil being produced and/or treated by the system is improved by providing each treatment tank in the system with a dual filtration system. The dual filtration system for each tank comprises a filter conditioning loop for substantially continuously withdrawing solution from the tank and removing particulate matter from the withdrawn solution and a system for removing surface impurities from the solution. In a first embodiment, the surface impurities removing system comprises an off-line solution filtration and replenishment system. In a second embodiment, the surface impurities removing system comprises a skimmer floating on the surface of the solution. The present invention has particular utility in systems for producing electrodeposited and/or treated copper foils.

Abstract: The present invention relates to a system for aligning a plurality of rollers in a metal or metal alloy foil production line. The alignment system comprises a reference frame having a longitudinal dimension parallel to the direction of foil travel through the production line and an optical alignment system movably mounted to the frame. The optical alignment system comprises a laser beam generator, beam splitters and a mirror for generating an orthogonal reference frame for aligning each foil contacting roller in the production line.

Abstract: A process is provided for solvent recovery from a hot gaseous mixture comprised of ammonia, carbon dioxide, cyanuric acid particles, and solvent vapors. The process comprises scrubbing the hot gaseous mixture with a liquid solvent to remove the cyanuric acid particles and to form a scrubbed gaseous mixture. The scrubbed gaseous mixture is cooled to form condensed liquid solvent and a cooled gaseous mixture containing traces of the solvent. The temperature of the cooled gaseous mixture is kept above that at which ammonium carbamate is formed by the reaction of ammonia with carbon dioxide. Condensed liquid solvent is separated from the cooled gaseous mixture and the cooled gaseous mixture is contacted with additional liquid solvent to form a substantially solvent-free gaseous mixture.

Abstract: A process for producing cyanuric acid by pyrolyzing urea in a solvent in a closed reactor having interior surfaces exposed to a gas zone, the improvement which comprises contacting the interior surfaces of the closed reactor with solvent in the presence of heat to inhibit the formation of solid deposits on the interior reactor surfaces.The process maintains high rates of heat transfer during the reaction period and reduces the frequency and cost of reactor cleaning.

Abstract: A process is described for the purification and recovery of cyanuric acid from a hot slurry of cyanuric acid in an organic solvent. In the process, the hot slurry is quenched in a quench liquid which is at a temperature for cooling the hot slurry to form a cooled slurry of cyanuric acid particles in a mixture of the solvent and the quench liquid. Cyanuric acid particles are separated from the mixture of solvent and quench liquid and recovered.The process effectively cools and separates cyanuric acid from the solvent and any color bodies present to produce a pure white crystalline product.