US3714125A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aromatic ortho-carbamates added to polyester polycondensation
Assignee: Teijin Ltd
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Filing: 1971-03-15
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Granted: 1973-01-30
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Expires: 1991-03-15
Abstract
Abstract DURING THE FORMATION OF A FIBER-FORMING POLYESTER BY THE REACTION OF A DICARBOXYLIC ACID OR ITS FUNCTIONAL DEERIVATIVE WITH A GLYCOL AN AROMATIC ORTHO-CARBONATE SUCH AS TETRAPHENYL CARBONATE IS ADDED AT A CERTAIN STAGE OF THE POLYCONDENSATION WHERE THE INTRINSIC VISCOSITY (N) OF THE POLYESTER IS AT LEAST 0.2 WHEREBY A FIBER-FORMING POLYESTER OF A LOW CONTENT OF FREE CARBOXYL GROUPS IS PREPARRED. MOREOVER THE REACTION RATE OF THE POLYCONDENSATION IS GREATELY INCREASED BY SELECTING AND USING A SUITABLE AROMATIC ORTHO-CARBONATE AND THEREFORE A FIBER-FORMING POLYESTER OF AVERY HIGH MOLECULAR WEIGHT CAN BE OBTANED.
Inventors
- 👤 T Shima
- 👤 T Urasaki
- 👤 I Oka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:00
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/06; C08G63/12; C08G63/16; C08G63/20; C08G63/78
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) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |