US2569440A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separation of isophthalic acid from terephthalic acid by noncatalytic esterification
Assignee: Texaco Inc
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Filing: 1949-08-11
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Granted: 1951-10-02
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Expires: 1969-08-11
Abstract
No abstract record available.
Inventors
- 👤 Robert J Agnew
- 👤 Robert E Conary
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:49
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/487; C07C51/493
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
47 words
A PROCESS FOR SEPARATING TEREPHTHALIC ACID, AND HOMOLOGS THEREOF FROM A MIXTURE OF BENZENE DICARBOXYLIC ACIDS WHICH COMPRISE SUBJECTING SAID MIXTURE TO NON-CATALYTIC ESTERIFICATION WITH A MONOHYDROXY ALCOHOL AT A TEMPERATURE BETWEEN 100 AND 225* C. AND SEPARATING NON-ESTERIFIED THEREPHTHALIC ACID, AND HOMOGLOGS THEREFO FROM THE MIXTURE.
Claim 2
Dependent Claim
47 words
A PROCESS FOR SEPARATING TEREPHTHALIC ACID, AND HOMOLOGS THEREOF FROM A MIXTURE OF BENZENE DICARBOXYLIC ACIDS WHICH COMPRISE SUBJECTING SAID MIXTURE TO NON-CATALYTIC ESTERIFICATION WITH A MONOHYDROXY ALCOHOL AT A TEMPERATURE BETWEEN 100 AND 225* C. AND SEPARATING NON-ESTERIFIED THEREPHTHALIC ACID, AND HOMOGLOGS THEREFO FROM THE MIXTURE.
References Cited (Backward Citations)
US1848724A
Cited
US1708404A
Cited
US1993736A
Cited
US2091241A
Cited
US2245528A
Cited
US2479066A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-10-01 | 1955-04-02 | 1955-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-10-01 | 1959-04-02 | 1959-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-10-01 | 1963-04-02 | 1963-10-02 | $7700.00 | Window Closed / Lapsed |