US4474681A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of aqueous suspensions of finely divided titanium dioxide
Assignee: BASF SE
•
Filing: 1982-07-02
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Granted: 1984-10-02
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Expires: 2002-07-02
Abstract
Abstract Aqueous suspensions of finely divided titanium dioxide are produced in the presence of dispersants by a process in which titanium dioxide powder and caprolactam are kneaded together in the dry state at from 15° to 40° C., the resulting mixture is kneaded with the addition of water, the paste thus obtained is suspended in water, the suspension is then allowed to sediment, and the resulting suspension containing finely divided titanium dioxide is decanted.
Inventors
- 👤 Horst Belde
- 👤 Hans Langenfelder
- 👤 Werner Hoerauf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:12
CPC Classifications
C; C09; C09D; C09D17/00; C09D17/004; C09D17/007; C09D17/008; Y; Y10; Y10S; Y10S516/00; Y10S516/924; Y10S516/928
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
69 words
A process for the production of an aqueous suspension of finely divided titanium dioxide which comprises kneading together in the dry state titanium dioxide powder and caprolactam at a temperature of from 15° to 40° C.; adding water to the resulting mixture and kneading the paste that is formed; suspending the paste in water; allowing the suspension to sediment and thereafter decanting the suspension containing finely divided titanium dioxide.
Claim 2
Dependent Claim
69 words
A process for the production of an aqueous suspension of finely divided titanium dioxide which comprises kneading together in the dry state titanium dioxide powder and caprolactam at a temperature of from 15° to 40° C.; adding water to the resulting mixture and kneading the paste that is formed; suspending the paste in water; allowing the suspension to sediment and thereafter decanting the suspension containing finely divided titanium dioxide.
Claim 3
Dependent Claim
27 words
A process as set forth in claim 4, wherein from 0.15 to 0.35 part by weight of caprolactam is present per part by weight of titanium dioxide.
Claim 4
Dependent Claim
26 words
A process as set forth in claim 4, wherein from 0.1 to 0.3% by weight, based on titanium dioxide, of an alkali metal phosphate is present.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-02 | 1988-04-02 | 1988-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-02 | 1992-04-02 | 1992-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-02 | 1996-04-02 | 1996-10-02 | $7700.00 | Window Closed / Lapsed |