Patent US3753933A successfully refreshed from Google Patents.
US3753933A
Expired / Lapsed
US
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Polyurethane foams from solid foaming agents
Assignee: Dow Chemical Co
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Filing: 1972-04-24
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Granted: 1973-08-21
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Expires: 1992-04-24
Abstract
Abstract POLYURETHANE FOAMS ARE PREPARED FROM A POLYOL AND AN ORGANIC POLYISOCYANATE EMPLOYING AS THE FOAMING AGENT A SOLID PARTICULATE SUBSTANCE HAVING A DECOMPOSITION OR DEHYDRATION TEMPERATURE ABOVE ABOUT 250*C., A MINIMUM DIMENSION PARTICLE SIZE OF LESS THAN 2 MILLIMETERS, AND A SURFACE AREA OF AT LEAST 0.2 SQUARE METERS PER GRAM. SUCH FOAMING AGENTS INCLUDE METAL POWDERS, ORGANIC POLYMER POWDERS AND INORGANIC COMPOUNDS.
Inventors
- 👤 F Olstowski
- 👤 D Parrish
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:28
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/06; C08J2375/00; C08J2375/04; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/253
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |