Patent EP0191691A1 successfully refreshed from Google Patents.
Patent US3033896A successfully refreshed from Google Patents.
US3033896A
Expired / Lapsed
US
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Preparation of sulphonated maleic acid esters of improved color
Assignee: GAF Chemicals Corp
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Filing: 1960-03-09
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Granted: 1962-05-08
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Expires: 1980-03-09
Abstract
No abstract record available.
Inventors
- 👤 Robert J Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:46
CPC Classifications
C; C07; C07C; C07C303/00; C07C303/42; C07C303/44
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
40 words
A METHOD OF IMPROVING THE COLOR OF A SULPHONATED ESTER OF MALEIC WHICH COMPRISES TREATING SAIS ESTR WITH ABOUT 0.001 TO ABOUT 0.0005 PARTS BY WEIGHT OF AN ALKALI METAL PHOSPHATE TO ABOUT 1 PART BY WEIGHT OF THE ESTER.
Claim 2
Independent Claim
40 words
A METHOD OF IMPROVING THE COLOR OF A SULPHONATED ESTER OF MALEIC WHICH COMPRISES TREATING SAIS ESTR WITH ABOUT 0.001 TO ABOUT 0.0005 PARTS BY WEIGHT OF AN ALKALI METAL PHOSPHATE TO ABOUT 1 PART BY WEIGHT OF THE ESTER.
References Cited (Backward Citations)
US2028091A
Cited
US2176423A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-05-07 | 1965-11-06 | 1966-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-05-07 | 1969-11-06 | 1970-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-05-07 | 1973-11-06 | 1974-05-08 | $7700.00 | Window Closed / Lapsed |