US3696180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing micro-porous polyurethane resin sheets by casting the resin on a porous sintered thermoplastic polymeric resin support surface
Assignee: Porous Plastics Ltd
•
Filing: 1970-05-11
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Granted: 1972-10-03
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Expires: 1990-05-11
Abstract
Abstract In a method of making artificial leathers and other water vapor permeable flexible sheet materials, a layer of polymer-containing mixture adhering to a temporary support is coagulated by suitable liquid treatment, dried, and then stripped from the support.
Inventors
- 👤 Victor Ralph Cunningham
- 👤 Thomas Stanley Dodson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:35
CPC Classifications
B; B29; B29C; B29C67/00; B29C67/20; B29C67/202; C; C08; C08J; C08J9/00; C08J9/26; C08J9/28; D; D06; D06N; D06N3/00; D06N3/0043; D06N3/0052; D06N3/0086; D06N3/0088; D06N3/0093; D06N3/0095; D06N3/0097; C08J2201/00; C08J2201/04; C08J2201/054; C08J2201/0542; C08J2201/0544; Y; Y10; Y10S; Y10S264/00; Y10S264/62
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
97 words
A method as claimed in claim 1 in which the support is formed by spreading an even layer of particles of thermoplastic organic polymeric plastics resin material on a smooth metal surface and then placing the smootH metal surface and the layer in a suitably heated oven to cause the particles to sinter, the surface of the sintered sheet which was in contact with the smooth metal surface being smoother than the other face of the sintered sheet and the layer of base zone working material being formed on the said smoother face of the sintered sheet.
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US3296016A
Cited
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Cited
US3414642A
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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) | 1975-10-03 | 1976-04-03 | 1976-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-03 | 1980-04-03 | 1980-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-03 | 1984-04-03 | 1984-10-03 | $7700.00 | Window Closed / Lapsed |