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US2945840A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for manufacture of a polyethylene terephthalate in finely divided form

Assignee: Imperial Chemical Industries Ltd
•
Filing: 1958-10-27
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Granted: 1960-07-19
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Expires: 1978-10-27
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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 05:05
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)

US2597643A Cited
US2762788A Cited
US2710848A Cited

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

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