US4938924A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Copper doping of eutectic solder
Assignee: AG Communication Systems Corp
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Filing: 1990-02-16
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Granted: 1990-07-03
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Expires: 2010-02-16
Abstract
Abstract Eutectic solder, including a combination of tin, lead and silver is doped by the addition of copper to substantially improve its effectiveness in soldering printed wiring cards which have been screen printed with conductors and mounting pads for components, with a low temperature, thick film cermet copper conductor. The addition of the copper substantially improves wetting and increases long term solder joint reliability.
Inventors
- 👤 Thomas Ozaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:58
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/30; H05K3/32; H05K3/34; H05K3/346; B; B23; B23K; B23K35/00; B23K35/22; B23K35/24; B23K35/26; B23K35/262; H05K1/00; H05K1/02; H05K1/09; H05K1/092
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
58 words
A eutectic solder including in combination 62 parts of tin, 36 parts of lead, and 2 parts of silver, for use in the soldering of low temperature thick film cermet copper conductors as utilized on printed wiring cards, the improvement comprising: adding to the eutectic solder combination, copper in the range of 0.2 to 0.3 percent by weight.
Claim 2
Dependent Claim
58 words
A eutectic solder including in combination 62 parts of tin, 36 parts of lead, and 2 parts of silver, for use in the soldering of low temperature thick film cermet copper conductors as utilized on printed wiring cards, the improvement comprising: adding to the eutectic solder combination, copper in the range of 0.2 to 0.3 percent by weight.
References Cited (Backward Citations)
US4070192A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-07-02 | 1994-01-01 | 1994-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-02 | 1998-01-01 | 1998-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-02 | 2002-01-01 | 2002-07-03 | $7700.00 | Window Closed / Lapsed |