US2863913A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing terephthalic acid
Assignee: Henkel AG and Co KGaA
•
Filing: 1955-01-07
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Granted: 1958-12-09
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Expires: 1975-01-07
Abstract
No abstract record available.
Inventors
- 👤 Raecke Bernhard
- 👤 Blaser Bruno
- 👤 Stein Werner
- 👤 Schirp Hubert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:08
CPC Classifications
E; E04; E04C; E04C5/00; E04C5/01; E04C5/02; E04C5/03; B; B21; B21B; B21B1/00; B21B1/16; B21B1/163; B21D; B21D11/00; B21D11/14; B21D11/15; B21H; B21H3/00; C; C07; C07C; C07C51/00; C07C51/41; C07C51/416; C21; C21D; C21D8/00; C21D8/06; C21D8/08; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
111 words
A PROCESS FOR THE PRODUCTION OF TEREPHTHALIC ACID WHICH COMPRISES HEATING AT LEAST ONE MATERIAL SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL SALTS OF BENZENE DICARBOXYLIC ACIDS WHEREIN THE CARBOXYL GROUPS STAND IN OTHER THAN PARA-POSITION RELATIVE TO EACH OTHER AND MIXTURES OF COMPOUNDS YIELDING ALKALI METAL SALTS WHEN HEATED UNDER THE REACTION CONDITIONS, TO A TEMPERATURE BETWEEN 340* AND 550*C. IN AN ATMOSPHERE SUBSTANTIALLY FREE FROM OXYGEN, AND IN THE PRESENCE OF A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF CADMIUM, ZINC, CADMIUM COMPOUNDS AND ZINC COMPOUNDS, TRANSFORMING THE ALKALI METAL SALT OF TEREPHTHALIC ACID FORMED THEREBY INTO TEREPHTHALIC ACID, AND SEPARATING THE TEREPHTHALIC ACID FROM THE REACTION MASS.
Claim 2
Dependent Claim
111 words
A PROCESS FOR THE PRODUCTION OF TEREPHTHALIC ACID WHICH COMPRISES HEATING AT LEAST ONE MATERIAL SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL SALTS OF BENZENE DICARBOXYLIC ACIDS WHEREIN THE CARBOXYL GROUPS STAND IN OTHER THAN PARA-POSITION RELATIVE TO EACH OTHER AND MIXTURES OF COMPOUNDS YIELDING ALKALI METAL SALTS WHEN HEATED UNDER THE REACTION CONDITIONS, TO A TEMPERATURE BETWEEN 340* AND 550*C. IN AN ATMOSPHERE SUBSTANTIALLY FREE FROM OXYGEN, AND IN THE PRESENCE OF A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF CADMIUM, ZINC, CADMIUM COMPOUNDS AND ZINC COMPOUNDS, TRANSFORMING THE ALKALI METAL SALT OF TEREPHTHALIC ACID FORMED THEREBY INTO TEREPHTHALIC ACID, AND SEPARATING THE TEREPHTHALIC ACID FROM THE REACTION MASS.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-12-08 | 1962-06-09 | 1962-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-12-08 | 1966-06-09 | 1966-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-12-08 | 1970-06-09 | 1970-12-09 | $7700.00 | Window Closed / Lapsed |