Method of detinning Sn plating layer on Cu-based material
AssigneeDowa Metaltech Co., Ltd.
InventorsHiroto Narieda, Yuta Sonoda, Masaaki Izaki
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Abstract
A Cu-based material 5 is immersed into an alkali hydroxide solution with a concentration of 3.0 to 37.5 mass % and a H2O2 solution with a concentration of 3.0 to 50.0 mass % is added in the alkali hydroxide solution, a temperature of the alkali hydroxide solution when the Cu-based material is immersed ranges from 60 to 105° C., a ratio A/B between a mol number A of alkali hydroxide in the alkali hydroxide solution and a mol number B of H2O2 in the H2O2 solution is 10 or more, and where a mol number of Sn in the Sn layer is C and a mol number of Sn in the CuSn layer is D, B≧C×2+D×6.
Claims10
A method of detinning a Sn plating layer on a Cu-based material for recycling the Cu-based material on which the Sn plating layer including a Sn layer and/or a CuSn layer is formed, said method comprising:
- immersing the Cu-based material into an alkali hydroxide solution with a concentration of 3.0 to 37.5 mass % and adding a H2O2 solution with a concentration of 3.0 to 50.0 mass % in the alkali hydroxide solution,
- wherein a temperature of the alkali hydroxide solution when the Cu-based material is immersed ranges from 60 to 105° C.,
- wherein a ratio A/B between a mol number A of alkali hydroxide in the alkali hydroxide solution and a mol number B of H2O2 in the H2O2 solution is 10 or more, and
- wherein where a mol number of Sn in the Sn layer is C and a mol number of Sn in the CuSn layer is D, B≧C×2+D×6.
Dependencies are inferred from the claim text.