Patent EP0406692A2 successfully refreshed from Google Patents.
EP0406692A2
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EP
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Fluid responsive to a magnetic field
Assignee: Northrop Grumman Space and Mission Systems Corp
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Filing: 1990-06-27
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Granted: —
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Expires: 2010-06-27
Abstract
Abstract A rheological fluid composition which is responsive to a magnetic field. The composition comprises magnetizable insulated, reduced carbonyl iron particles, a vehicle and a dispersant. The dispersant comprises fibrous carbon particles.
Inventors
- 👤 Emil Meyer Shtarkman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 05:33
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/44; H01F1/447
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
39 words
In a rheological fluid composition which is responsive to a magnetic field, which fluid composition comprises a vehicle, and a solid magnetizable particulate suspended in said vehicle, the improvement wherein said magnetizable particulate is an insulated, reduced carbonyl iron.
Claim 2
Dependent Claim
39 words
In a rheological fluid composition which is responsive to a magnetic field, which fluid composition comprises a vehicle, and a solid magnetizable particulate suspended in said vehicle, the improvement wherein said magnetizable particulate is an insulated, reduced carbonyl iron.
Claim 3
Dependent Claim
27 words
The fluid composition of claim 1 wherein said composition comprises a dispersant for dispersing the magnetizable particulate throughout the vehicle, the vehicle being the composition continuous phase.
Claim 4
Dependent Claim
30 words
The fluid composition of claim 2 wherein said dispersant comprises fibrous carbon particles, the fibers of which have a length-to-diameter ratio in the range of about 10:1 to about 1,000:1.
Claim 5
Dependent Claim
21 words
The fluid composition of claim 3 wherein said vehicle has a viscosity in the range of about one-1,000 centipoises at 100°F.
Claim 6
Dependent Claim
52 words
The fluid composition of claim 4 wherein said composition comprises: a mixture of carbonyl iron and a dispersant comprising about 0.5%-10% by weight of said dispersant and about 90% to 99.5% by weight of said carbonyl iron; and a vehicle in the amount of about 15%-50% of the weight of said mixture.
Claim 7
Dependent Claim
55 words
In a rheological fluid composition which is responsive to a magnetic field, which fluid composition comprises a vehicle, a solid magnetizable particulate suspended in said vehicle, and a dispersant, the improvement wherein said dispersant comprises fibrous carbon particles the fibers of which have a length-to-diameter ratio in the range of about 10:1 to about 1,000:1.
Claim 8
Dependent Claim
55 words
In a rheological fluid composition which is responsive to a magnetic field, which fluid composition comprises a vehicle, a solid magnetizable particulate suspended in said vehicle, and a dispersant, the improvement wherein said dispersant comprises fibrous carbon particles the fibers of which have a length-to-diameter ratio in the range of about 10:1 to about 1,000:1.
Claim 9
Dependent Claim
21 words
The fluid composition of claim 6 wherein said carbon fibers have a surface area of about 300 square meters per gram.
Claim 10
Dependent Claim
16 words
The fluid composition of claim 7 wherein said magnetizable particulate is an insulated, reduced carbonyl iron.
Claim 11
Dependent Claim
49 words
The fluid composition of claim 8 comprising a mixture of carbonyl iron and a dispersant comprising about 0.5%-10% by weight of said dispersant and about 90% to 99.5% by weight of said carbonyl iron, and a vehicle in the amount of about 15%-50% of the weight of said mixture.
References Cited (Backward Citations)
No citation records indexed.
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