| 摘要 |
PURPOSE:To effectively utilize an etching soln. contg. iodine and to efficiently replenish iodine by drawing a part of the etching soln. from a chemical etching tank after chemical etching, electrolyzing the drawn soln. in an electrolytic cell provided with a diaphragm and feeding the regenerates soln. in the anode chamber back to the etching tank. CONSTITUTION:A material 9 to be etched such as an Au-Pd alloy is immersed in an etching soln. contg. iodine in a chemical etching tank 8 and chemical etching is carried out. After the etching, part of the etching soln. is drawn and fed to an electrolytic cell 4 divided into an anode chamber 2 and a cathode chamber 3 with a carbon exchange membrane 1. In the cell 4, the drawn soln. is electrolyzed with an insoluble anode 5 and a stainless steel cathode 6. Iodine is produced in the anode chamber 2 and the regenerated etching soln. is fed to the etching tank 8 in combination with a fresh etching soln. fed from a replenishing hole 15 as required. The fed etching soln. is reutilized in the tank 8 and Au, Pd, etc., are recovered in the cathode chamber 3. |
