| 摘要 |
PURPOSE:To safely regenerate an etchant at a low cost by regenerating an etchant of ferric chloride by means of air oxidation. CONSTITUTION:In the main body 1 of air oxidation equipment consisting of a device 1a for removing mist, a spray 1b, a packing material 1c, an air blower 1d, a blast pipe 1e, a pump 4, etc., an etchant of ferric chloride is sprayed at about 60 deg.C via the spray 1b. Subsequently, air is fed from the air blower 1d to oxidize the etchant, and this etchant is moved into a chemical addition tank 2, where hydrochloric acid and water are properly and automatically added through a supply pipe 2e based on the values measured by means of an oxidation-reduction electrometer 2b, a specific gravity measurement sensor 2c, an acid concentration measurement electrometer 2d, etc., and the resulting mixture is agitated. This etchant is allowed to flow via a transport tube 5 into an etching device 3 and then circulated into the spray 1b in the main body 1 of the air oxidation equipment by means of the pump 4. By this method, etching can be safely and inexpensively carried out while keeping the concentration of ferric chloride at the prescribed conditions. |
