Patent US3743620A successfully refreshed from Google Patents.
US3743620A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyurethane solutions and methods for the production of uniformly microporous polyurethane sheet material therefrom
Assignee: Tenneco Polymers Inc
•
Filing: 1970-12-10
•
Granted: 1973-07-03
•
Expires: 1990-12-10
Abstract
Abstract A SOLUTION OF A POLYURETHANE POLYMER CONTAINING A SUBSTANCE, SUCH AS AN ALKALI METAL HALIDE, TO IMPROVE THE PROPERTIES OF A MICROPOROUS FILM PREPARED FROM THE SOLUTION AND A PROCESS FOR PREPARING A UNIFORMLY MICROPOROUS FILM FROM SUCH A SOLUTION ARE PROVIDED.
Inventors
- 👤 B Frye
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:40
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/22; B32B5/24; B32B5/245; C; C08; C08J; C08J9/00; C08J9/26; C08J9/28; C08K; C08K3/00; C08K3/16; D; D04; D04H; D04H1/00; D04H1/40; D04H1/58; D04H1/64; D04H1/68; B32B2260/00; B32B2260/04; B32B2260/046; B32B2262/00; B32B2262/02; B32B2262/0261; B32B2262/0269; B32B2266/00; B32B2266/02; B32B2266/0214; B32B2266/0264; B32B2266/0278; C08J2375/00; C08J2375/04
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1976-07-02 | 1977-01-01 | 1977-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-02 | 1981-01-01 | 1981-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-02 | 1985-01-01 | 1985-07-03 | $7700.00 | Window Closed / Lapsed |