US3571679A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for forming electrets
Assignee: Nederlandse Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek TNO
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Filing: 1969-10-08
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Granted: 1971-03-23
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Expires: 1989-10-08
Abstract
Abstract A device for forming electrets with an open structure, which is provided with electrodes which are covered with a material, the specific resistance of which is a factor of 104-108 smaller than that of the electret material and the thickness of which is chosen such that it can stand the forming voltage applied without the occurrence of a dielectric breakdown.
Inventors
- 👤 Jan Van Turnhout
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:01
CPC Classifications
H; H01; H01G; H01G7/00; H01G7/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
86 words
A device for forming electrets from dielectrics with an open or porous structure comprising two metal electrodes between which an electric field can be excited and between which the dielectrics can be brought, wherein at least one electrode is covered and the specific resistance of the cover is a factor of 104-108 smaller than that of the dielectric to be formed and wherein the thickness of the cover is chosen such that it can stand the forming voltage applied without the occurrence of a dielectric breakdown.
Claim 2
Independent Claim
86 words
A device for forming electrets from dielectrics with an open or porous structure comprising two metal electrodes between which an electric field can be excited and between which the dielectrics can be brought, wherein at least one electrode is covered and the specific resistance of the cover is a factor of 104-108 smaller than that of the dielectric to be formed and wherein the thickness of the cover is chosen such that it can stand the forming voltage applied without the occurrence of a dielectric breakdown.
References Cited (Backward Citations)
US3365633A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-22 | 1974-09-21 | 1975-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-22 | 1978-09-21 | 1979-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-22 | 1982-09-21 | 1983-03-23 | $7700.00 | Window Closed / Lapsed |