APPARATUS FOR REGENERATION OF COPPER-CONTAINING ETCHING SOLUTIONS Russian patent published in 1997 - IPC

FIELD: etching process. SUBSTANCE: apparatus and electrodes of waterproof material (advantageously carbon cloth) are made in the form of coaxial cylinders. Reservoir space is separated by electrodes into three cavities intercommunicating through electrodes. Etching solution is withdrawn from etch bath or another vessel and pumped into space between reservoir wall and external electrode, filtered through external and internal electrodes and is further directed from space formed by internal electrode through connecting pipe into etch bath. External electrode is wired to negative pole of constant current source, and internal one to positive pole. On external electrode, metal copper is formed, and, on internal electrode, oxidation potential of solution increases. EFFECT: increased versatility due to improved conditions of mass exchange on electrode surface. 3 cl, 2 dwg