US5217638A
Expired / Lapsed
US
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Electroviscous fluid
Assignee: Mitsubishi Chemical Corp
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Filing: 1990-10-11
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Granted: 1993-06-08
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Expires: 2010-10-11
Abstract
Abstract An electroviscous fluid comprising an electrical insulating liquid and fine particles dispersed therein, wherein the fine particles are spherical particles containing an electrolytic solution, obtained by hydrolysis and polycondensation of a metal alkoxide or its derivative.
Inventors
- 👤 Eiji Hattori
- 👤 Yasuo Oguri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:54
CPC Classifications
C; C10; C10M; C10M171/00; C10M171/001
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
61 words
An electroviscous fluid comprising an electrical insulating liquid, an electrolytic solution and particles of 0.05 to 2μm diameter dispersed therein, wherein said particles are spherical particles having a standard deviation in diameter of not more than 1.2 obtained by hydrolysis and polycondensation of a metal alkoxide selected from the group consisting of Si, Ti, Zr, Ba-Ti, Sr-Ti, Pb-Ti, Pb-Ti-Zr and Li-Nb.
Claim 2
Dependent Claim
61 words
An electroviscous fluid comprising an electrical insulating liquid, an electrolytic solution and particles of 0.05 to 2μm diameter dispersed therein, wherein said particles are spherical particles having a standard deviation in diameter of not more than 1.2 obtained by hydrolysis and polycondensation of a metal alkoxide selected from the group consisting of Si, Ti, Zr, Ba-Ti, Sr-Ti, Pb-Ti, Pb-Ti-Zr and Li-Nb.
Claim 3
Dependent Claim
23 words
The electroviscous fluid according to claim 1, wherein the electrolytic solution comprises of a polar solvent having a higher boiling point than water.
Claim 4
Dependent Claim
14 words
The electroviscous fluid according to claim 2, wherein the polar solvent is ethylene glycol.
Claim 5
Dependent Claim
43 words
The electroviscous fluid according to claim 1, wherein the electrolytic solution has an electrolyte concentration of from 0.1 to 90% by weight, and the electrolytic solution contained in the spherical particles is in an amount of from 0.1 to 20 % by weight.
Claim 6
Dependent Claim
47 words
The electroviscous fluid according to claim 1, 2 or 3 wherein the electrolytic solution has an electrolyte concentration of from 5 to 50 % by weight, and the electrolytic solution contained in the spherical particles is in an amount of from 1 to 10 % by weight.
Claim 7
Dependent Claim
24 words
The electroviscous fluid according to claim 1 wherein the amount of the fine particles in the electroviscous fluid is from 5 to 50 %.
Claim 8
Dependent Claim
15 words
The electroviscous fluid according to claim 1, wherein the metal alkoxide comprises lower alkoxy groups.
Claim 9
Dependent Claim
14 words
The electroviscous fluid according to claim 1 wherein, the metal alkoxide is silicone tetraethoxide.
Claim 10
Dependent Claim
66 words
The electroviscous fluid according to claim 4, wherein the electrolyte is at least one member selected from the group consisting of NH 3 , NaOH, NaCl, LiCl, B 2 O 3 Ca(OH) 2 , MgSO 4 , Fe(SO 4 ) 2 , sodium sulfonate, sodium carboxylate, sodium alkylbenzene sulfonate, sodium polystyrene sulfonate, calcium salt of fatty acid and condensation product of naphthalene sulfonic acid with formalin.
Claim 11
Dependent Claim
21 words
The electroviscous fluid according to claim 1, wherein the standard deviation from the particle diameter is not more than 1.1 .
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-06-07 | 1996-12-07 | 1997-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-07 | 2000-12-07 | 2001-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-07 | 2004-12-07 | 2005-06-08 | $7700.00 | Window Closed / Lapsed |