Patent US2820023A successfully refreshed from Google Patents.
US2820023A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ester interchange reaction using a lanthanum catalyst
Assignee: EIDP Inc
•
Filing: 1954-11-15
•
Granted: 1958-01-14
•
Expires: 1974-11-15
Abstract
No abstract record available.
Inventors
- 👤 Cavanaugh Robert Morris
- 👤 Dempster Jane Bowen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:20
CPC Classifications
C; C07; C07C; C07C67/00; C07C67/03; B; B01; B01J; B01J23/00; B01J23/10; B01J23/14; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/84
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
122 words
A PROCESS FOR THE MANUFACTURE OF ESTERS OF DICARBOXYLIC ACIDS, WHICH COMPRISES REACTING AT A TEMPERATURE FROM 150*C. TO ABOUT 290*C. A GLYCOL OF THE GENERAL FORMULA HO-(CH2)N-OH, IN WHICH N IS A NUMBER NOT LESS THAN 2 AND NOT GREATER THAN 10, WITH A COMPOUND FROM THE GROUP CONSISTING OF THE DICARBOXYLIC ACIDS IN WHICH EACH CARBOXYL GROUP HAS BEEN ESTERIFIED BY AN ALCOHOL CONTAINING NOT MORE THAN FOUR CARBON ATOMS, SAID REACTION BEING CARRIED OUT IN THE PRESENCE OF A CATALYST TAKEN FROM THE CLASS CONSISTING OF METALLIC LANTHANUM, LANTHANUM OXIDE, LANTHAMUM SALTS OF AN ACID HAVING AN EQUILIBRIUM CONSTANT OF LESS THAN 10-*2, AND LANTHANUM SALTS OF AN ACID HAVING A BOILING POINT AT ATMOSPHERIC PRESSURE BELOW ABOUT 100*C.
Claim 2
Dependent Claim
122 words
A PROCESS FOR THE MANUFACTURE OF ESTERS OF DICARBOXYLIC ACIDS, WHICH COMPRISES REACTING AT A TEMPERATURE FROM 150*C. TO ABOUT 290*C. A GLYCOL OF THE GENERAL FORMULA HO-(CH2)N-OH, IN WHICH N IS A NUMBER NOT LESS THAN 2 AND NOT GREATER THAN 10, WITH A COMPOUND FROM THE GROUP CONSISTING OF THE DICARBOXYLIC ACIDS IN WHICH EACH CARBOXYL GROUP HAS BEEN ESTERIFIED BY AN ALCOHOL CONTAINING NOT MORE THAN FOUR CARBON ATOMS, SAID REACTION BEING CARRIED OUT IN THE PRESENCE OF A CATALYST TAKEN FROM THE CLASS CONSISTING OF METALLIC LANTHANUM, LANTHANUM OXIDE, LANTHAMUM SALTS OF AN ACID HAVING AN EQUILIBRIUM CONSTANT OF LESS THAN 10-*2, AND LANTHANUM SALTS OF AN ACID HAVING A BOILING POINT AT ATMOSPHERIC PRESSURE BELOW ABOUT 100*C.
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) | 1961-01-13 | 1961-07-15 | 1962-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-13 | 1965-07-15 | 1966-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-13 | 1969-07-15 | 1970-01-14 | $7700.00 | Window Closed / Lapsed |