Patent US2847397A successfully refreshed from Google Patents.
US2847397A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of polycondensation of diolesters of aromatic dicarboxylic acids
Assignee: Glanzstoff AG
•
Filing: 1953-12-22
•
Granted: 1958-08-12
•
Expires: 1973-12-22
Abstract
No abstract record available.
Inventors
- 👤 Kleine Johannes
- 👤 Siggel Erhard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:52
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/81
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
102 words
PROCESS FOR PRODUCING POLYMERIZED GLYCOL ESTERS OF TEREPHTHALIC ACID OF HIGH PURITY WHICH COMPRISES HEATING THE MONOMERIC ESTER AND A CONDENSATION CATALYST AT A TEMPERATURE OF ABOUT 200* TO 240*C. IN A MIXTURE OF ABOUT 60 PERCENT OF AN INERT SOLVENT FOR THE POLYMER SELECTED FROM THE GROUP CONSISTING OF DIPHENYLMETHANE, DIPHENYL OXIDE, DIPHENYL, AND METHYL-NAPHENYLMETHANE, ABOUT 40 PERCENT OF A HYDROCARBON NONSOLVENT BOILING IN THE RANGE OF ABOUT 140* TO 240*C., BOTH OF SAID SOLVENT AND NON-SOLVENT BEING CAPABLE OF FORMING AN AZEOTROPE WITH EXCESS GLYCOL SPLIT OFF DURING THE CONDENSATION, AND REMOVING THE AZEOTROPE OF GLYCOL, INERT SOLVENT, AND NONSOLVENT.
Claim 2
Dependent Claim
102 words
PROCESS FOR PRODUCING POLYMERIZED GLYCOL ESTERS OF TEREPHTHALIC ACID OF HIGH PURITY WHICH COMPRISES HEATING THE MONOMERIC ESTER AND A CONDENSATION CATALYST AT A TEMPERATURE OF ABOUT 200* TO 240*C. IN A MIXTURE OF ABOUT 60 PERCENT OF AN INERT SOLVENT FOR THE POLYMER SELECTED FROM THE GROUP CONSISTING OF DIPHENYLMETHANE, DIPHENYL OXIDE, DIPHENYL, AND METHYL-NAPHENYLMETHANE, ABOUT 40 PERCENT OF A HYDROCARBON NONSOLVENT BOILING IN THE RANGE OF ABOUT 140* TO 240*C., BOTH OF SAID SOLVENT AND NON-SOLVENT BEING CAPABLE OF FORMING AN AZEOTROPE WITH EXCESS GLYCOL SPLIT OFF DURING THE CONDENSATION, AND REMOVING THE AZEOTROPE OF GLYCOL, INERT SOLVENT, AND NONSOLVENT.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-08-11 | 1962-02-10 | 1962-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-08-11 | 1966-02-10 | 1966-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-08-11 | 1970-02-10 | 1970-08-12 | $7700.00 | Window Closed / Lapsed |