US3390961A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of titanium dioxide pigment with organic sequestering agents
Assignee: KEMIRA Inc A GA CORP
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Filing: 1965-05-20
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Granted: 1968-07-02
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Expires: 1985-05-20
Abstract
No abstract record available.
Inventors
- 👤 Jr George Leathwhite Roberts
- 👤 Whately Walter Royce
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:16
CPC Classifications
C; C09; C09C; C09C1/00; C09C1/36; C09C1/3607; C09C1/3669; C01; C01P; C01P2006/00; C01P2006/60
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
73 words
A METHOD FOR IMPROVING THE COLOR OF FINELY-DIVIDED TIO2 PIGMENT CONTAMINATED WITH COLOR-FORMING IMPURITIES WHICH COMPRISES MIXING THE PIGMENT WITH WATER AND ORGANIC SEQUESTERING AGENT TO FORM AN AQUEOUS SLURRY CONTAINING COLOR-FORMING IMPURITIES, SAID SEQUESTERING AGENT FORMING A COMPLEX WITH THE COLOR-FORMING IMPUITITES, SAID COMPLEX HAVING GREATER STABILITY THAN COMPOUNDS OF THE COLOR-FORMING IMPURITIES WHICH ARE INSOLUBLE AND ADSORBABLE ON THE PIGMENT, AND RECOVERING A TIO2 PIGMENT OF IMPROVED COLOR FROM SAID SLURRY.
Claim 2
Independent Claim
73 words
A METHOD FOR IMPROVING THE COLOR OF FINELY-DIVIDED TIO2 PIGMENT CONTAMINATED WITH COLOR-FORMING IMPURITIES WHICH COMPRISES MIXING THE PIGMENT WITH WATER AND ORGANIC SEQUESTERING AGENT TO FORM AN AQUEOUS SLURRY CONTAINING COLOR-FORMING IMPURITIES, SAID SEQUESTERING AGENT FORMING A COMPLEX WITH THE COLOR-FORMING IMPUITITES, SAID COMPLEX HAVING GREATER STABILITY THAN COMPOUNDS OF THE COLOR-FORMING IMPURITIES WHICH ARE INSOLUBLE AND ADSORBABLE ON THE PIGMENT, AND RECOVERING A TIO2 PIGMENT OF IMPROVED COLOR FROM SAID SLURRY.
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) | 1971-07-02 | 1972-01-01 | 1972-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-07-02 | 1976-01-01 | 1976-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-07-02 | 1980-01-01 | 1980-07-02 | $7700.00 | Window Closed / Lapsed |