US5601696A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silver plating baths and silver plating method using the same
Assignee: EEJA Ltd
•
Filing: 1995-10-03
•
Granted: 1997-02-11
•
Expires: 2015-10-03
Abstract
Abstract An object is to provide practical silver plating technique, high-speed silver plating technique and silver strike plating technique which have, respectively, substantially the same performance as cyanide baths without use of any toxic cyanide. A hydantoin compound of the following general formula is contained as a complex-forming agent <IMAGE> [wherein R1, R3 and R5 independently represent hydrogen, an alkyl group having 1-5 carbon atoms, an aryl group or an alcohol].
Inventors
- 👤 Takanobu Asakawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:36
CPC Classifications
C; C25; C25D; C25D3/00; C25D3/02; C25D3/46
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
118 words
A silver electroplating bath consisting of at least one inorganic acid salt of silver used as a silver compound, at least one hydantoin compound of the following formula used as a complex-forming agent ##STR6## wherein R 1 , R 3 and R 5 each independently represent hydrogen, an alkyl group having 1-5 carbon atoms, an aryl group or an alcohol, and ##STR7## wherein R 1 , R 3 , R 5 and R 5 ' each independently represent hydrogen, an alkyl group having 1-5 carbon atoms, an aryl group or an alcohol, and at least one of a salt of an inorganic acid and a carboxylate as a conductive salt said bath optionally containing a gloss controlling agent.
Claim 2
Dependent Claim
118 words
A silver electroplating bath consisting of at least one inorganic acid salt of silver used as a silver compound, at least one hydantoin compound of the following formula used as a complex-forming agent ##STR6## wherein R 1 , R 3 and R 5 each independently represent hydrogen, an alkyl group having 1-5 carbon atoms, an aryl group or an alcohol, and ##STR7## wherein R 1 , R 3 , R 5 and R 5 ' each independently represent hydrogen, an alkyl group having 1-5 carbon atoms, an aryl group or an alcohol, and at least one of a salt of an inorganic acid and a carboxylate as a conductive salt said bath optionally containing a gloss controlling agent.
Claim 3
Dependent Claim
31 words
The silver electroplating bath according to claim 1, wherein said at least one inorganic acid salt of silver used as a silver compound is silver nitrate, silver oxide, or mixtures thereof.
Claim 4
Dependent Claim
23 words
The silver electroplating bath according to claim 1, wherein said complex-forming agent is at least one of 1-methylhydantoin, 1,3-dimethylhydantoin, 5,5-dimethylhydantoin, 1-methanol-5,5-dimethylhydantoin, and 5,5-diphenylhydantoin.
Claim 5
Dependent Claim
39 words
The silver electroplating bath according to claim 1, wherein at least one of an organic sulfur compound having a SH group or a carboxyl group, a S-containing amino acid, or sulfite ions is introduced as a gloss controlling agent.
Claim 6
Dependent Claim
22 words
The silver electroplating bath according to claim 1, wherein potassium chloride, potassium formate, or mixtures thereof is introduced as the conductive salt.
Claim 7
Dependent Claim
58 words
The silver electroplating bath according to claim 1, wherein said silver is contained in an amount of 1-100 g/l as a metal concentration, said complex-forming agent is contained in an amount of 10 -15 -10 -2 mol/l as a concentration of silver ions in the bath, and said conductive salt is contained in an amount of 1-100 g/l.
Claim 8
Dependent Claim
38 words
A silver electroplating method wherein said silver plating bath according to claim 1 is employed under working conditions of a pH of 8-13, a liquid temperature of 30°-90° C. and a current density of 1-20 A/dm 2 .
Claim 9
Dependent Claim
13 words
A high-speed silver electroplating bath consisting of the bath composition of claim 1.
Claim 10
Dependent Claim
59 words
The high-speed silver electroplating bath according to claim 8, wherein said silver is contained in an amount of 1-150 g/l as a metal concentration, said complex-forming agent is contained in an amount of 10 -15 -10 -2 mol/l as a concentration of silver ions in the bath, and said conductive salt is contained in an amount of 1-100 g/l.
Claim 11
Dependent Claim
40 words
A high-speed silver electroplating method wherein the high-speed silver plating bath according to claim 9 is employed under working conditions of a pH of 8-13, a liquid temperature of 30°-90° C. and a current density of 10-150 A/dm 2 .
Claim 12
Dependent Claim
40 words
A high-speed silver electroplating method wherein said high-speed silver plating bath according to claim 8 is employed under working conditions of a pH of 8-13, a liquid temperature of 30°-90° C. and a current density of 10-150 A/dm 2 .
Claim 13
Dependent Claim
13 words
A silver strike electroplating bath consisting of the bath composition of claim 1.
Claim 14
Dependent Claim
59 words
A silver strike electroplating bath according to claim 12, wherein said silver is contained in an amount of 0.1-5 g/l as a metal concentration, said complex-forming agent is contained in an amount of 10 -15 -10 -2 mol/l as a concentration of silver ions in the bath, and said conductive salt is contained in a amount of 1-100 g/l.
Claim 15
Dependent Claim
45 words
A silver strike electroplating method wherein said silver strike plating bath according to claim 13 is employed under working conditions of a pH of 7-13, a liquid temperature of 20°-90° C. and a current density of 1-20 A/dm 2 or a voltage of 1-20 V.
Claim 16
Dependent Claim
45 words
A silver strike electroplating method wherein said silver strike plating bath according to claim 12 is employed under working conditions of a pH of 7-13, a liquid temperature of 20°-90° C. and a current density of 1-20 A/dm 2 or a voltage of 1-20 V.
References Cited (Backward Citations)
US3018232A
Cited
US4246077A
Cited
JPS527335A
Cited
JPS5439329A
Cited
JPS54155132A
Cited
US4399006A
Cited
JPS59150095A
Cited
JPH02290993A
Cited
JPH07166391A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-02-11 | 2000-08-12 | 2001-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-02-11 | 2004-08-12 | 2005-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-02-11 | 2008-08-12 | 2009-02-11 | $7700.00 | Window Closed / Lapsed |