US4645614A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electroviscous liquids
Assignee: Metzeler Kautschuk GmbH
•
Filing: 1985-07-09
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Granted: 1987-02-24
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Expires: 2005-07-09
Abstract
Abstract The electroviscous suspension is based on a mixture of aqueous silica gel with silicone oil as the liquid phase to which a dispersant is added. The dispersant consists of amino functional or silicon-functional polysiloxanes having a molecular weight above 800. The concentration of the dispersant is from 1 to 30% by weight and preferably from 5 to 20% by weight, based on the silica gel particles. Electroviscous suspensions such as these are distinguished by the fact that they are highly compatible with elastomeric materials, non-sedimenting, non-inflammable and physiologically acceptable. In addition, they are heat- and freeze-resistant over a wide temperature range and are largely unaffected by temperature and pressure in their viscosity.
Inventors
- 👤 John Goossens
- 👤 Gunter Oppermann
- 👤 Wolfgang Grape
- 👤 Volker Hartel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:09
CPC Classifications
C; C10; C10M; C10M171/00; C10M171/001; C08; C08K; C08K3/00; C08K3/34; C08K3/36; C08L; C08L83/00; C08L83/04; C10M107/00; C10M107/50; C10M113/00; C10M113/12; C10M125/00; C10M125/26; C10M155/00; C10M155/02; C10M169/00; C08G; C08G77/00; C08G77/04; C08G77/045; C08G77/14; C08G77/16; C08G77/18; C08G77/22; C08G77/26; C08G77/70; C10M2201/00; C10M2201/087; C10M2201/10; C10M2201/102; C10M2201/105; C10M2229/00; C10M2229/02; C10M2229/025; C10M2229/04; C10M2229/0405; C10M2229/041; C10M2229/0415; C10M2229/042; C10M2229/0425; C10M2229/043; C10M2229/0435; C10M2229/044; C10M2229/0445; C10M2229/045; C10M2229/0455; C10M2229/046; C10M2229/0465; C10M2229/047; C10M2229/0475; C10M2229/048; C10M2229/0485; C10M2229/05; C10M2229/0505; C10M2229/051; C10M2229/0515; C10M2229/052; C10M2229/0525; C10M2229/053; C10M2229/0535; C10M2229/054; C10M2229/0545; C10N; C10N2020/00; C10N2020/01; C10N2040/00; C10N2040/14; C10N2040/16; C10N2040/17; C10N2040/175; C10N2040/18; C10N2040/185; Y; Y10; Y10S; Y10S516/00; Y10S516/01; Y10S516/07
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
76 words
An electroviscous suspension comprising more than 25% by weight of silica gel with a water content of from 1 to 15% by weight as the disperse phase and silicone oil as the liquid phase and also a dispersant, wherein the dispersant comprises a functional polysiloxane selected from the group consisting of an amino functional polysiloxane, a hydroxy functional polysiloxane, an acetoxy functional polysiloxane and an alkoxy functional polysiloxane, said polysiloxane having a molecular weight above 800.
Claim 2
Dependent Claim
76 words
An electroviscous suspension comprising more than 25% by weight of silica gel with a water content of from 1 to 15% by weight as the disperse phase and silicone oil as the liquid phase and also a dispersant, wherein the dispersant comprises a functional polysiloxane selected from the group consisting of an amino functional polysiloxane, a hydroxy functional polysiloxane, an acetoxy functional polysiloxane and an alkoxy functional polysiloxane, said polysiloxane having a molecular weight above 800.
Claim 3
Dependent Claim
29 words
An electroviscous suspension as claimed in claim 1, wherein the functional polysiloxane is added in a concentration of from 1 to 30% by weight, based on the silica gel.
Claim 4
Dependent Claim
32 words
An electroviscous suspension as claimed in claim 1 wherein the amino functional polysiloxane has the following formula: in which 1< n<1000, m=0 to 5, R=H or C 1 -C 8 alkyl and
Claim 5
Dependent Claim
20 words
An electroviscous suspension wherein the amino functional polysiloxane has the following formula: ##STR14## with m=0 to 3 and 1< n<1000.
Claim 6
Dependent Claim
20 words
An electroviscous suspension wherein the amino functional polysiloxane has the following formula: ##STR14## with m=0 to 3 and 1< n<1000.
Claim 7
Dependent Claim
42 words
An electroviscous suspension as claimed in claim 1 wherein the functional polysiloxane has the following formula ##STR15## in which 1< n<1000 and Y is hydrolyzable group selected from the group consisting of a hydroxy group, an alkoxy group and a carboxy group.
Claim 8
Dependent Claim
29 words
An electroviscous suspension as claimed in claim 1, wherein the functional polysiloxane is added in a concentration of from 5 to 20% by weight, based on the silica gel.
Claim 9
Dependent Claim
21 words
An electroviscous suspension as claimed in claim 3, wherein X is a difunctional hydrocarbon radical containing 1 to 6 carbon atoms.
Claim 10
Dependent Claim
21 words
An electroviscous suspension as claimed in claim 3, wherein X is a difunctional hydrocarbon radical containing one or more N atoms.
Claim 11
Dependent Claim
21 words
An electroviscous suspension as claimed in claim 3, wherein X is a difunctional hydrocarbon radical containing one or more O atoms.
Claim 12
Dependent Claim
27 words
An electroviscous suspension as claimed in claim 3, wherein X is a difunctional hydrocarbon radical containing one or more N atoms and one or more O atoms.
Claim 13
Dependent Claim
33 words
An electroviscous suspension as claimed in claim 3, wherein X is a difunctional hydrocarbon radical selected from the group consisting of CH 2 --CH 2 --CH 2 --NH--CH 2 --CH 2 , ##STR16##
Claim 14
Dependent Claim
19 words
An electroviscous suspension as claimed in claim 5, wherein the functional polysiloxane contains 20 to 300 dimethyl siloxane units.
Claim 15
Dependent Claim
25 words
An electroviscous suspension as claimed in claim 1, wherein the silicone oil is selected from the group consisting of polydimethyl siloxane and polymeric methylphenyl siloxane.
Claim 16
Dependent Claim
25 words
An electroviscous suspension as claimed in claim 1, wherein the silicone oil has a viscosity at room temperature of 3 to 300 mm 2 /s.
Claim 17
Dependent Claim
25 words
An electroviscous suspension as claimed in claim 1, wherein the silicone oil has a viscosity at room temperature of 3 to 10 mm 2 /s.
Claim 18
Dependent Claim
24 words
An electroviscous suspension as claimed in claim 1, wherein the amino functional polysiloxane has the following formula ##STR17## wherein n is 15 to 100.
Claim 19
Dependent Claim
14 words
An electroviscous suspension as claimed in claim 16, wherein n is 30 to 70.
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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) | 1990-02-23 | 1990-08-25 | 1991-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-23 | 1994-08-25 | 1995-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-23 | 1998-08-25 | 1999-02-24 | $7700.00 | Window Closed / Lapsed |