Patent US2728831A successfully refreshed from Google Patents.
US2728831A
Expired / Lapsed
US
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Electric hygrometer
Assignee: Phys-Chemical Res Corp
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Filing: 1951-11-09
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Granted: 1955-12-27
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Expires: 1971-11-09
Abstract
No abstract record available.
Inventors
- 👤 Pope Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:47
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/12; G01N27/121
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
34 words
A HUMIDITY SENSITIVE ELEMENT COMPRISING A BODY MEMBER FORMED OF A SOLID, ELECTRICALLY INSULATING CROSSLINKED ORGANIC POLYMER, SAID BODY MEMBER HAVING AN ION EXCHANGE MATERIAL ONLY IN A THIN LAYER AT THE SURFACE OF
Claim 2
Dependent Claim
34 words
A HUMIDITY SENSITIVE ELEMENT COMPRISING A BODY MEMBER FORMED OF A SOLID, ELECTRICALLY INSULATING CROSSLINKED ORGANIC POLYMER, SAID BODY MEMBER HAVING AN ION EXCHANGE MATERIAL ONLY IN A THIN LAYER AT THE SURFACE OF
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-12-26 | 1959-06-27 | 1959-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-12-26 | 1963-06-27 | 1963-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-12-26 | 1967-06-27 | 1967-12-27 | $7700.00 | Window Closed / Lapsed |