US4247708A
Expired / Lapsed
US
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Method for rendering fine oxide powder hydrophobic
Assignee: Tosoh Corp
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Filing: 1979-01-24
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Granted: 1981-01-27
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Expires: 1999-01-24
Abstract
Abstract A method for imparting a hydrophobic property to a fine oxide powder by treating it with an organo-polysiloxane in the presence of an alkali catalyst. The method is carried out with at least 1.5% by weight of organo-polysiloxane of molecular weight not exceeding 10,000, at least 0.5% by weight of ammonia or an aliphatic amine of a boiling point lower than 100 DEG C. and at least 1.5% by weight of water are added to a dry weight of the fine oxide powder (a quantity obtained after removal of adsorption water content under reduced pressure not exceeding 5 mmHg in mercury meter at 100 DEG to 110 DEG C.). Of these additives, the ammonia or the aliphatic amine of a boiling point not exceeding 100 DEG C. is added at a temperature not exceeding 60 DEG C. Then, after an aging process for at least 15 minutes, heating is carried out to a temperature between 60 DEG and 150 DEG 0 C. for a period of at least 30 minutes. All processes are carried out under normal pressure.
Inventors
- 👤 Yukihiro Tsutsumi
- 👤 Yutaka Fukuda
- 👤 Kenichi Matsubara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:18
CPC Classifications
C; C08; C08G; C08G83/00; C08G83/001; C08K; C08K9/00; C08K9/04; C08K9/06; C09; C09C; C09C3/00; C09C3/006; C09C3/06; C09C3/08; C09C3/12; C01; C01P; C01P2006/00; C01P2006/90
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
216 words
A method for manufacturing a hydrophobic fine oxide powder comprising: (a) adding to a fine inorganic oxide powder having surface hydroxyl groups, at least 1.5% by weight based on a dry weight of said fine oxide powder said dry weight being measured after removal of a water content by adsorption under reduced pressure not exceeding 5 mm Hg at 100° to 110° C., of a linear-chain dimethyl organo-polysiloxane having a molecular weight not exceeding 10,000 which shows a viscosity value within a range of 1 to 100 centistokes at 25° C.; (b) adding at least 0.5% by weight, based on said dry weight of said fine oxide powder, of a compound selected from the group consisting of ammonia and an aliphatic amine having a boiling point of lower than 100° C., wherein said compound is added at a temperature below 60° C.; (c) aging the resulting mixture for at least fifteen minutes at atmospheric pressure in the presence of water in a quantity of at least 1.5% by weight based on said dry weight of said fine powder; wherein essentially no solvent is used in said mixture, and (d) heating said mixture to a temperature between 60° and 150° C. at atmospheric pressure whereby the surface hydroxyl groups of the fine powder react with the organopolysiloxane.
Claim 2
Independent Claim
216 words
A method for manufacturing a hydrophobic fine oxide powder comprising: (a) adding to a fine inorganic oxide powder having surface hydroxyl groups, at least 1.5% by weight based on a dry weight of said fine oxide powder said dry weight being measured after removal of a water content by adsorption under reduced pressure not exceeding 5 mm Hg at 100° to 110° C., of a linear-chain dimethyl organo-polysiloxane having a molecular weight not exceeding 10,000 which shows a viscosity value within a range of 1 to 100 centistokes at 25° C.; (b) adding at least 0.5% by weight, based on said dry weight of said fine oxide powder, of a compound selected from the group consisting of ammonia and an aliphatic amine having a boiling point of lower than 100° C., wherein said compound is added at a temperature below 60° C.; (c) aging the resulting mixture for at least fifteen minutes at atmospheric pressure in the presence of water in a quantity of at least 1.5% by weight based on said dry weight of said fine powder; wherein essentially no solvent is used in said mixture, and (d) heating said mixture to a temperature between 60° and 150° C. at atmospheric pressure whereby the surface hydroxyl groups of the fine powder react with the organopolysiloxane.
Claim 3
Dependent Claim
37 words
A method for rendering a fine oxide powder hydrophobic according to claim 1, wherein said organo-polysiloxane is a linear dimethyl polysiloxane which shows a viscosity value within a range from 10 to 50 centistokes at 25° C.
Claim 4
Dependent Claim
37 words
A method for rendering a fine oxide powder hydrophobic according to claim 1 wherein either a part of or the whole of said water to be added is the adsorption water content of said fine oxide powder.
Claim 5
Dependent Claim
53 words
A method for rendering a fine oxide powder hydrophobic according to claim 1, wherein, after said organo-polysiloxane is added to and mixed with said fine oxide powder, said compounds selected from the group consisting of ammonia and an aliphatic amine of a boiling point lower than 100° C. and water are added simultaneously.
Claim 6
Dependent Claim
44 words
A method for rendering a fine oxide powder hydrophobic according to claim 1, wherein said fine oxide powder is at least one of a group consisting of silica, diatom earth, asbestos, activated clay, talc, alumina, iron oxide, magnesium oxide, titanium oxide and glass balls.
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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) | 1984-01-27 | 1984-07-28 | 1985-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-27 | 1988-07-28 | 1989-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-27 | 1992-07-28 | 1993-01-27 | $7700.00 | Window Closed / Lapsed |