US4015031A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for hydrophobizing silicas and silicates with organosilanes
Assignee: Evonik Operations GmbH
•
Filing: 1976-02-02
•
Granted: 1977-03-29
•
Expires: 1996-02-02
Abstract
Abstract Finely divided hydrophobic silica or silicate is produced by treating the dry, moving particles with an organic silane at elevated temperature. The silica or silicate which had been prepared by wet precipitation or pyrogenically and which is in powdered form is heated to a temperature of about 200° to 300° C. with agitation and is brought to a fluidized condition and then is treated dropwise with an organosilane which is stable and boils below 300° C.
Inventors
- 👤 Helmut Reinhardt
- 👤 Karl Trebinger
- 👤 Gottfried Kallrath
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:57
CPC Classifications
C; C09; C09C; C09C1/00; C09C1/28; C09C1/30; C09C1/3081; C01; C01P; C01P2006/00; C01P2006/12
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
116 words
In a process for hydrophobization of finely divided silica or silicate by treatment of dry moving particles of powdery silica or silicate produced by wet precipitation or pyrogenically with an organosilane at an elevated temperature the improvement comprising stirring the silica or silicate in a container at about 200° to 300° C. to bring the silica or silicate to a fluidized condition and while the silica or silicate is in said fluidized condition at said temperature treating the silica or silicate dropwise with an organosilane which is stable at said temperature and boils below 300° C., said organosilane having an active group which will react with the surface of the silica or silicate to be hydrophobized.
Claim 2
Dependent Claim
116 words
In a process for hydrophobization of finely divided silica or silicate by treatment of dry moving particles of powdery silica or silicate produced by wet precipitation or pyrogenically with an organosilane at an elevated temperature the improvement comprising stirring the silica or silicate in a container at about 200° to 300° C. to bring the silica or silicate to a fluidized condition and while the silica or silicate is in said fluidized condition at said temperature treating the silica or silicate dropwise with an organosilane which is stable at said temperature and boils below 300° C., said organosilane having an active group which will react with the surface of the silica or silicate to be hydrophobized.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein the organosilane is an alkyl halosilane or an alkyl alkoxysilane.
Claim 4
Dependent Claim
17 words
The process of claim 2 wherein the organosilane comprises a dialkyl dihalosilane or a dialkyl dialkoxy silane.
Claim 5
Dependent Claim
14 words
The process of claim 2 wherein the organo silane is an alkyl alkoxy silane.
Claim 6
Dependent Claim
14 words
The process of claim 4 wherein the alkyl alkoxy silane comprise dimethyl dimethoxy silane.
Claim 7
Dependent Claim
12 words
The process of claim 2 wherein the organosilane is an alkyl halosilane.
Claim 8
Dependent Claim
12 words
The process of claim 6 wherein the organosilane is an alkyl chlorosilane.
Claim 9
Dependent Claim
11 words
The process of claim 7 wherein the organosilane comprises dimethyl dichlorosilane.
Claim 10
Dependent Claim
25 words
The process of claim 1 wherein sufficient organosilane is employed to provide a carbon content of 1.75 to 1.9% on the treated silica or silicate.
References Cited (Backward Citations)
CA519230A
Cited
US2993809A
Cited
US3012861A
Cited
US3924029A
Cited
US3600326A
Cited
US3830738A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-28 | 1980-09-27 | 1981-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-28 | 1984-09-27 | 1985-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-28 | 1988-09-27 | 1989-03-29 | $7700.00 | Window Closed / Lapsed |