US2974122A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Making high linear polyester with magnesium hypophosphite catalyst
Assignee: Acordis UK Ltd
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Filing: 1957-05-07
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Granted: 1961-03-07
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Expires: 1977-05-07
Abstract
No abstract record available.
Inventors
- 👤 Lincoln James
- 👤 Hawthorne Brian James
- 👤 Kowolik Ernest Jan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:23
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/83
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
119 words
A PROCESS FOR THE MANUFACTURE OF A HIGH LINEAR POLYESTER FROM A LOWER LINEAR POLYESTER OF A LOWER ALKYLENE GLYCOL AND AN AROMATIC DICARBOXYLIC ACID SELECTED FROM THE GROUP CONSISTING OF TEREPHTHALIC ACID, DIPHENYL-4.4''DICARBOXYLIC ACID, A-B-DIPHENYLETHANE-4.4''-DICARBOXYLIC ACID, A,O-DIPHENYLBUTANE-4.4''-DIPHENYLBUTANE-4.4''A,B-DISPHENOXYETHANE-4.4'' -DICARBOXYLIC ACID, A-O-DIPHENOXYBUTANE-4.4H-DICARBOXYLIC ACID, 1.5-NAPHTHALENE-DICARBOXYLIC ACID, 2.6-NAPHTHALENE-DICARBOXYLIC ACID, AND 2.7NAPHTHALENE-DICARBOXYLIC ACID, SAID LOWER POLYESTER HAVING AN INTRINSIC VISCOSITY OF 0.1 TO 0.4, WHICH COMPRISES HEATING THE SAID LOWER POLYESTER AT A TEMPERATURE OF 250*-300*C. IN THE PRESENCE OF MAGNESIUM HYPOHOSPHITE AS CATALYST, THE AMOUNT OF MAGNESIUM HYPOPHOSPHITE, RECKONED AS MAGNESIUM, BEING LESS THAN 0.05 PERCENT OF THE WEIGHT OF HIGH LINEAR POLYESTER THEORETICALLY OBTAINABLE, AND CONTINUING THE HEATING UNTIL THE INTRINSIC VISCOSITY OF THE POLYESTER IS INCREASED TO AT LEAST 0.5.
Claim 2
Dependent Claim
119 words
A PROCESS FOR THE MANUFACTURE OF A HIGH LINEAR POLYESTER FROM A LOWER LINEAR POLYESTER OF A LOWER ALKYLENE GLYCOL AND AN AROMATIC DICARBOXYLIC ACID SELECTED FROM THE GROUP CONSISTING OF TEREPHTHALIC ACID, DIPHENYL-4.4''DICARBOXYLIC ACID, A-B-DIPHENYLETHANE-4.4''-DICARBOXYLIC ACID, A,O-DIPHENYLBUTANE-4.4''-DIPHENYLBUTANE-4.4''A,B-DISPHENOXYETHANE-4.4'' -DICARBOXYLIC ACID, A-O-DIPHENOXYBUTANE-4.4H-DICARBOXYLIC ACID, 1.5-NAPHTHALENE-DICARBOXYLIC ACID, 2.6-NAPHTHALENE-DICARBOXYLIC ACID, AND 2.7NAPHTHALENE-DICARBOXYLIC ACID, SAID LOWER POLYESTER HAVING AN INTRINSIC VISCOSITY OF 0.1 TO 0.4, WHICH COMPRISES HEATING THE SAID LOWER POLYESTER AT A TEMPERATURE OF 250*-300*C. IN THE PRESENCE OF MAGNESIUM HYPOHOSPHITE AS CATALYST, THE AMOUNT OF MAGNESIUM HYPOPHOSPHITE, RECKONED AS MAGNESIUM, BEING LESS THAN 0.05 PERCENT OF THE WEIGHT OF HIGH LINEAR POLYESTER THEORETICALLY OBTAINABLE, AND CONTINUING THE HEATING UNTIL THE INTRINSIC VISCOSITY OF THE POLYESTER IS INCREASED TO AT LEAST 0.5.
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) | 1964-03-06 | 1964-09-05 | 1965-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-03-06 | 1968-09-05 | 1969-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-03-06 | 1972-09-05 | 1973-03-07 | $7700.00 | Window Closed / Lapsed |