US3830759A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for reducing diethylene glycol formation in poly(ethylene terephthalate)prepolymer
Assignee: Eastman Kodak Co
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Filing: 1972-12-07
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Granted: 1974-08-20
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Expires: 1992-12-07
Abstract
Abstract FORMATION OF CONTAMINANT DIETHYLENE GLYCOL BY-PRODUCT DURING MANUFACTURE OF POLY(ETHYLENE TEREPHTHALATE) PREPOLYMER BY ESTER EXCHANGE OF DIMETHYL TEREPHTHALATE AND ETHYLENE GLYCOL IN THE PRESENCE OF A CATALYST MIXTURE IS MINIMIZED BY INCLUDING LITHIUM ACETATE DIHYDRATE AS AN ESSENTIAL INGREDIENT IN THE CATALYST MIXTURE WITH ZINC ZCETATE DIHYDRATE AND/OR ANTIMONY TRIOXIDE.
Inventors
- 👤 K Barkey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:20
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/83; C08G63/80
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) | 1977-08-19 | 1978-02-18 | 1978-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-19 | 1982-02-18 | 1982-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-19 | 1986-02-18 | 1986-08-20 | $7700.00 | Window Closed / Lapsed |