Patent US2945840A successfully refreshed from Google Patents.
US2945840A
Expired / Lapsed
US
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Process for manufacture of a polyethylene terephthalate in finely divided form
Assignee: Imperial Chemical Industries Ltd
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Filing: 1958-10-27
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Granted: 1960-07-19
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Expires: 1978-10-27
Abstract
No abstract record available.
Inventors
- 👤 Roberts John Francis Lloyd
- 👤 Twitchett Harry James
- 👤 Wild Arthur Scott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:57
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; C08J3/14; C08J2367/00; C08J2367/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
119 words
A PROCESS FOR THE MANUFACTURE OF POLYETHYLENE TEREPHTHALATE IN A FINELY DIVIDED PARTICULATE FORM WHICH COMPRISES ADDING A DILUTE AQUEOUS SOLUTION OF A HALOGENATED ACETIC ACID CONTAINING BETWEEN 20% AND 40% BY WEIGHT OF THE HALOGENATED ACETIC ACID TO A SOLUTION OF POLYETHYLENE TEREPHTHALATE IN A SOLVENT SELECTED FROM THE GROUP OF SOLVENTS CONSISTING OF HALOGENATED ACETIC ACIDS AND CONCENTRATED AQUEOUS SOLUTIONS OF HALOGENATED ACETIC ACIDS CONTAINING NOT LESS THAN 80% BY WEIGHT OF HALOGENATED ACETIC ACID, SAID DILUTE AQUEOUS SOLUTION BEING ADDED TO SAID POLYETHYLENE TEREPHTHALATE SOLUTION IN AND AMOUNT SO THAT THE RESULTING MIXTURE CONTAINS BETWEEN 50% AND 65% BY WEIGHT OF HALOGENATED ACETIC ACID, AND THEREAFTER ISOLATING THE FINELY DIVIDED PARTICULATE POLYETHYLENE TEREPHTHALATE WHICH IS PRECIPITATED.
Claim 2
Dependent Claim
119 words
A PROCESS FOR THE MANUFACTURE OF POLYETHYLENE TEREPHTHALATE IN A FINELY DIVIDED PARTICULATE FORM WHICH COMPRISES ADDING A DILUTE AQUEOUS SOLUTION OF A HALOGENATED ACETIC ACID CONTAINING BETWEEN 20% AND 40% BY WEIGHT OF THE HALOGENATED ACETIC ACID TO A SOLUTION OF POLYETHYLENE TEREPHTHALATE IN A SOLVENT SELECTED FROM THE GROUP OF SOLVENTS CONSISTING OF HALOGENATED ACETIC ACIDS AND CONCENTRATED AQUEOUS SOLUTIONS OF HALOGENATED ACETIC ACIDS CONTAINING NOT LESS THAN 80% BY WEIGHT OF HALOGENATED ACETIC ACID, SAID DILUTE AQUEOUS SOLUTION BEING ADDED TO SAID POLYETHYLENE TEREPHTHALATE SOLUTION IN AND AMOUNT SO THAT THE RESULTING MIXTURE CONTAINS BETWEEN 50% AND 65% BY WEIGHT OF HALOGENATED ACETIC ACID, AND THEREAFTER ISOLATING THE FINELY DIVIDED PARTICULATE POLYETHYLENE TEREPHTHALATE WHICH IS PRECIPITATED.
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) | 1963-07-19 | 1964-01-18 | 1964-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-07-19 | 1968-01-18 | 1968-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-07-19 | 1972-01-18 | 1972-07-19 | $7700.00 | Window Closed / Lapsed |