Abstract: A dielectric coating for a circuit board which is adherent to electroless copper. The coating is an epoxy dielectric including an amount of a solubilized nitrile-free butadiene or isoprene agent for promoting adhesion of an electroless copper coating. A method for producing a circuit board is also disclosed.

Abstract: A method for waste treating metal containing solutions comprising decomposing the metal from the solution in the substantial absence of air and separating the decomposed (precipitated) metal from the solution.

Abstract: Process for the planting of through-holes in an epoxy printed circuit board base material in the manufacture of printed circuit boards. The treatment process is designed to increase adhesion between the epoxy board material and a subsequently deposited metal plate. The process is characterized, in part, by the use of an activated permanganate solution.

Abstract: Process for the plating of through-holes in an epoxy printed circuit board base material in the manufacture of printed circuit boards. The treatment process is designed to increase adhesion between the epoxy board material and a subsequently deposited metal plate. The process is characterized, in part, by the use of an activated permanganate solution.

Abstract: An improved alkaline permanganate composition for etching printed circuit boards is provided by incorporating a secondary oxidant in the solution capable of oxidizing manganate ion to permanganate ion.

Abstract: A method for the recovery and reuse of an expensive palladium-tin catalyst whereby alkali hydroxide or carbonate is added to the exhausted catalytic solution and/or the spent rinse water solution to precipitate out a catalyst residue, which is then filtered, collected, washed, and dissolved in a hydrohalide acid and adjusted to a predetermined concentration.

Abstract: An improved alkaline permanganate composition for etching printed circuit boards is provided by incorporating a secondary oxidant in the solution capable of oxidizing manganate ion to permanganate ion.

Abstract: An improved process for dissolution of metals by etching, and particularly the etching of copper in printed circuit board processing or the like, using an aqueous H.sub.2 O.sub.2 --H.sub.2 SO.sub.4 etching solution, in which the concentration of H.sub.2 SO.sub.4 in the etching solution is allowed to decrease during use of the etching solution from an initial, relatively high level at the time the etching solution is put into use, to a final, relatively low level. When a predetermined concentration of dissolved etched metal exists in the etching solution, the etching solution is removed from use, H.sub.2 SO.sub.4 is added to increase the concentration of H.sub.2 SO.sub.4 in the etching solution to approximately the initial, relatively high level, and the metal is precipitated out of the etching solution.

Abstract: A method is provided for selective removal of copper contaminants from aqueous activator solutions which also contain palladium and tin. It comprises placement of insoluble electrodes in the aqeuous solution and application of a low voltage, preferably ranging from between 0.05 to 5.0 volts across the electrodes, whereby metallic copper is selectively deposited upon the cathode, with palladium and tin remaining in the aqueous solutions. Typically, the soluble copper ions are present as contaminants in activator solutions utilized in various electroless metal plating processes.

Abstract: A method is provided for selectively separating and removing complexed heavy metal ions, preferably copper or nickel, from complexing agents in aqueous solution and removing substantially all heavy metal ions while leaving complexing agent in said solution. In preferred embodiments, complexed copper or complexed nickel is selectively removed from aqueous effluent from electroless plating systems by passage through a bed of chelating ion-exchange resin having an iminodiacetic acid functionality. Substantially all copper or nickel will be removed from solution and retained in the resin bed and the complexing agent will pass through for conventional waste treatment or disposal. The copper or nickel is recovered by elution from the resin bed with an acid solution and may, if desired, be precipitated by addition of sodium hydroxide or the like and subsequently separated for recovery or disposal.