To provide a method for prolonging the use period and life of a soln. for electroless tin plating to copper products.
The soln. for reclaiming contg. a dilute soln. for tin plating is introduced into an electrolytic cell 2. This electrolytic cell 2 has a cathode chamber 3 which is provided with a cathode 6 built therein, an intermediate chamber 4 and an anode chamber 5 which is provided with an anode 7 built therein and is packed with an anolyte. A potential difference is loaded between the cathode 6 and the anode 7. The cathode chamber 3 is isolated by an anion exchange membrane 8 and the anode chamber 5 by a cation exchange membrane 9 from the intermediate chamber 4. The soln. for reclamation is first introduced into the cathode chamber 3 and is stagnated therein while allowing the copper to deposit on the cathode 6. The soln. for reclamation decreased in the copper after the stagnation time is introduced into the intermediate chamber 4 and the tin is increased by the tin ions transmitted through the cation exchange membrane from the anode chamber 5.
HARNISCHMACHER WERNER
FISCHWASSER KLAUS
LIEBER HANS-WILHELM
BLITTERSDORF RALPH
HEUS ANNETTE
