Abstract: Vertical photoresist developer for processing of any size of printed circuit boards carried on a processing cassette. The processing cassette is carried by a chain through a main chamber, a rinse chamber and a drying chamber, all the processing chambers in line with each other. The processing system is electromechanical and electrically controlled, as well as air and liquid flow control. The developer is system oriented and symmetrical in operation to either side of the board. A printed circuit board holder with gripper fingers mounted in removable plastic chain cassette carries the board through separable processing chambers.

Abstract: Vertical photoresist developer for processing of any size of printed circuit boards carried on a processing cassette. The processing cassette is carried by a chain through a main chamber, a rinse chamber and a drying chamber, all the processing chambers in line with each other. The processing system is electromechanical and electrically controlled, as well as air and liquid flow control. The developer is system oriented and symmetrical in operation to either side of the board.

Abstract: Solder stripping solution having an extended life for stripping and removing tin-lead alloy solder or tin deposits from entire circuits or tabs with an insignificant amount of attack on the base epoxy laminate or underlay copper or nickel substrate while leaving a residue-free substrate surface. This solution can be utilized at room temperature or preferably slightly above, and has a prolonged useful life of weeks to months. The composition of the solution includes a hydroxyphenol in an aqueous solution of a nitro-substituted aromatic compound, an inorganic acid, and thiourea.

Abstract: Solder stripping solution having an extended life for stripping and removing tin-lead alloy solder or tin deposits from entire circuits or tabs with an insignificant amount of attack on the base epoxy laminate or underlay copper or nickel substrate while leaving a residue-free substrate surface. This solution can be utilized at room temperature or preferably slightly above, and has a prolonged useful life of weeks to months. The composition of the solution includes a hydroxyphenol in an aqueous solution of a nitro-substituted aromatic compound, an inorganic acid, and thiourea.