Title:
ELECTROLESS TIN-SILVER ALLOY PLATING BATH
Document Type and Number:
Japanese Patent JP3419995
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To obtain smooth and dense plating coating by incorporating a complexing agent stabilizing tin into a soln. contg. divalent tin compounds and univalent silver compounds.
SOLUTION: This plating soln. consists essentially of the following (1) and (2): (1) denotes divalent tin noncyanic compounds such as tin oxide and univalent silver noncyanic compounds such as silver oxide and (2) denotes additives for stably retaining the univalent silver compounds in the soln. and includes compounds selected from six kinds among thiourea or its derivatives, etc., or one or more kinds thereamong. Moreover, additives for retaining the divalent tin compounds in the aq. soln., surfactants for refining precipitated metallic grains and obtaining smooth coating, or the like are added thereto. In this way, the silver ions are stably dissolved in the bath, the preferential precipitation of silver is suppressed, and plating low in the content of silver in the coating is made possible. As a result, it can substitute for solder contg. lead which has a problem from the viewpoint of environmental hygiene.
Inventors:
Obata Keigo
Tetsuya Kondo
Tetsuya Kondo
Application Number:
JP13973296A
Publication Date:
June 23, 2003
Filing Date:
May 10, 1996
Export Citation:
Assignee:
Daiwa Chemical Research Institute Co., Ltd.
International Classes:
C23C18/44; C22C13/00; C23C18/48; (IPC1-7): C23C18/48
Domestic Patent References:
| JP8239774A | ||||
| JP5221763A | ||||
| JP5287543A | ||||
| JP5112874A | ||||
| JP4289178A | ||||
| JP797467A | ||||
| JP5020362A | ||||
| JP9296274A |
Attorney, Agent or Firm:
Motohiro Kurauchi (1 outside)