US2808339A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for improving lightfastness of lead chromate
Assignee: EIDP Inc
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Filing: 1953-10-16
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Granted: 1957-10-01
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Expires: 1973-10-16
Abstract
No abstract record available.
Inventors
- 👤 Jackson Julius
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:01
CPC Classifications
C; C09; C09C; C09C1/00; C09C1/14; C09C1/20; C01; C01P; C01P2002/00; C01P2002/80; C01P2002/84; C01P2006/00; C01P2006/60
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
90 words
IN A PROCESS FOR IMPROVING THE LIGHT-FASTNESS OF A LEAD CHROMATE PIGMENT BY PRECIPITATING A HYDROUS METAL OXIDE SELECTED FROM THE GROUP CONSISTING OF ALUMINUM, TITANIUM, TIN, HAFNIUM, THORIUM, COLUMBIUM, TANTALUM, ANTIMONY, BISMUTH AND MIXTURES THEREOF, IN THE PRESENCE OF SAID PIGMENT IN AQUEOUS SUSPENSION, AND THEN RECOVERING THE LEAD CHROMATE PIGMENT WITH IMPROVED LIGHT-FASTNESS THE IMPROVEMENT WHICH COMPRISES PRECIPITATING SAID HYDROUS METAL OXIDE IN THE AQUEOUS SUSPENSION OF THE LEAD CHROMATE IN THE PRESENCE OF FROM ABOUT 3% TO 5% OF MANGANESE SULFATE, BASED ON THE FINAL PIGMENT WEIGHT.
References Cited (Backward Citations)
US2365171A
Cited
US2430589A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-09-30 | 1961-04-01 | 1961-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-09-30 | 1965-04-01 | 1965-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-09-30 | 1969-04-01 | 1969-10-01 | $7700.00 | Window Closed / Lapsed |