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Patent US5011627A successfully refreshed from Google Patents.
US5011627A
Expired / Lapsed
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Screen-printable paste for manufacturing electrically conductive coatings
Assignee: Evonik Operations GmbH
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Filing: 1989-03-07
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Granted: 1991-04-30
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Expires: 2009-03-07
Abstract
Abstract Membrane keyboards are manufactured using screen-printable, electrically conductive pastes consisting of 40 to 75% by weight of metal powder (silver, aluminum, copper and their mixtures), 5 to 55% by weight of an organic solvent and 5-20% by weight of and synthetic resin based on a thermoplastic epoxy or phenoxy resin with an average molecular weight of 10,000 to 250,000 and an epoxide content of 0 to 1.
Inventors
- 👤 Klaus Lutz
- 👤 Hans-Joachim Baer
- 👤 Karl-Anton Starz
- 👤 Werner Leske
- 👤 Harry Mueller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:15
CPC Classifications
C; C09; C09D; C09D5/00; C09D5/24; H; H01; H01B; H01B1/00; H01B1/20; H01B1/22; H05; H05K; H05K1/00; H05K1/02; H05K1/09; H05K1/092; H05K1/095
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
89 words
A screen-printable paste consisting essentially of 40 to 75% by weight of an electrically conductive metal powder selected from the group consisting of silver, aluminum, copper and mixtures thereof, 5 to 20% by weight of an organic synthetic resin and 5 to 55% by weight of an organic solvent for producing electrically conductive coatings on a flexible plastic sheet wherein a thermoplastic epoxy or phenoxy resin with an average molecular weight of 10,000 to 250,000 and an epoxy content of 0 to 1 equ./kg is the organic synthetic resin.
Claim 2
Dependent Claim
89 words
A screen-printable paste consisting essentially of 40 to 75% by weight of an electrically conductive metal powder selected from the group consisting of silver, aluminum, copper and mixtures thereof, 5 to 20% by weight of an organic synthetic resin and 5 to 55% by weight of an organic solvent for producing electrically conductive coatings on a flexible plastic sheet wherein a thermoplastic epoxy or phenoxy resin with an average molecular weight of 10,000 to 250,000 and an epoxy content of 0 to 1 equ./kg is the organic synthetic resin.
Claim 3
Dependent Claim
20 words
The screen-printable paste according to claim 1, wherein the epoxy or phenoxy resins are prepared from bisphenol A and epichlorohydrin.
Claim 4
Dependent Claim
21 words
The screen-printable paste according to claim 1, wherein the solvent is a glycol ether, glycol ether ester, glycol ester or hydrocarbon.
References Cited (Backward Citations)
US4410457A
Cited
US4479890A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-04-29 | 1994-10-29 | 1995-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-04-29 | 1998-10-29 | 1999-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-04-29 | 2002-10-29 | 2003-04-30 | $7700.00 | Window Closed / Lapsed |