Patent US4227935A successfully refreshed from Google Patents.
US4227935A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High dry hide TiO2 slurries
Assignee: KEMIRA Inc A GA CORP
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Filing: 1979-02-16
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Granted: 1980-10-14
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Expires: 1999-02-16
Abstract
Abstract High dry hide titanium dioxide pigment slurries are prepared from in-process material which is treated with low amounts of aluminum oxide.
Inventors
- 👤 David W. Blake
- 👤 Alberto W. Delgado
- 👤 Gerard M. Sheehan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:22
CPC Classifications
C; C09; C09C; C09C1/00; C09C1/36; C09C1/3607; C09C1/3653; C09C1/3661; C09D; C09D17/00; C09D17/004; C09D17/007; C09D17/008; C01; C01P; C01P2004/00; C01P2004/80; C01P2004/82; C01P2004/84
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
69 words
In an aqueous titanium dioxide pigment slurry having high hiding power, a solids content of about 55 to 70 percent by weight, and an effective amount of a dispersing agent, the improvement comprising using undried, unmilled hydroclassified fines as the source of the titanium dioxide wherein said fines pass through a 325 mesh screen and are coated with about 0.3 to 3 percent by weight of hydrous aluminum oxide.
Claim 2
Dependent Claim
69 words
In an aqueous titanium dioxide pigment slurry having high hiding power, a solids content of about 55 to 70 percent by weight, and an effective amount of a dispersing agent, the improvement comprising using undried, unmilled hydroclassified fines as the source of the titanium dioxide wherein said fines pass through a 325 mesh screen and are coated with about 0.3 to 3 percent by weight of hydrous aluminum oxide.
Claim 3
Dependent Claim
23 words
The slurry of claim 1 wherein up to about 60 percent of the fines is replaced by dried and milled titanium dioxide pigment.
Claim 4
Dependent Claim
16 words
The slurry of claim 1 wherein the fines are formed by the combustion of titaniferous salts.
Claim 5
Dependent Claim
33 words
The slurry of claim 3 wherein the combustion of titaniferous salts is performed in the presence of aluminum chloride so as to burn in up to about 2 percent by weight aluminum oxide.
Claim 6
Dependent Claim
19 words
The slurry of claim 1 wherein the fines are derived from the hydrolysis of a titanium iron sulfate solution.
Claim 7
Dependent Claim
32 words
The slurry of claim 5 wherein the resultant hydrolysate is calcined in the presence of an aluminum salt so as to burn in up to about 2 percent by weight aluminum oxide.
Claim 8
Dependent Claim
17 words
The slurry of claim 1 wherein the solids content is about 60 to 65 percent by weight.
Claim 9
Dependent Claim
26 words
The slurry of claim 1 wherein the fines, which are in the form of a dilute slurry, are concentrated by filtration or evaporation of the water.
References Cited (Backward Citations)
US3595822A
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US3847640A
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US3941603A
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US4115144A
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US4022636A
Cited
US4097301A
Cited
US4170485A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-10-14 | 1984-04-14 | 1984-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-14 | 1988-04-14 | 1988-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-14 | 1992-04-14 | 1992-10-14 | $7700.00 | Window Closed / Lapsed |