Stably dispersed magnetic viscous fluid

• US 6,780,343 B2
• Filed: 05/01/2002
• Issued: 08/24/2004
• Est. Priority Date: 07/31/2000
• Status: Expired due to Term

• Current Assignee: KAO Corporation
• Original Assignee: Bando Chemical Industries Limited, KAO Corporation
• Inventors: Hata, Katsuhiko, Kiga, Nozomi, Miyanaga, Seiichi
• Primary Examiner(s): Koslow, C. Melissa
• Application Number:
  US10/089,495
• Publication Number:
  US 20030006395A1
• Time in Patent Office: 846 Days
• Field of Search: 252/62.52
• US Class Current: 252/62.52
• CPC Class Codes: C08G 65/22 Cyclic ethers having at least one atom other than carbon and hydrogen outside the ring
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 71/02 Polyalkylene oxides
• CPC Class Codes: H01F 1/44 of magnetic liquids, e.g. ferrofluids particles in a bonding agent H01F1/28, H01F1/36, H01F1/37
• CPC Class Codes: H01F 1/447 characterised by magnetoviscosity, e.g. magnetorheological, magnetothixotropic, magnetodilatant liquids electrorheological fluids C10M171/001

Abstract

The present invention is directed to a stabilized dispersion magnetorheological fluid comprising a magnetic particle, a dispersive medium and a dispersing agent

wherein said dispersing agent is a polyether containing a polymer unit represented by the following general formula (1):

in the formula, R¹ represents a hydrogen atom or a hydrocarbon group of 1 to 22 carbon atoms; R² represents a hydrogen atom, a hydrocarbon group of 1 to 22 carbon atoms which may optionally have a substituent, or —(AO)m-R³; R³ represents a hydrocarbon group of 1 to 22 carbon atoms which may optionally have a substituent; A represents an alkylene group of 1 to 3 carbon atoms; m represents an integer of 1 to 50; and A groups which number m may be the same or different.

Claims

1. A stabilized dispersion magnetorheological fluid comprising a magnetic particle, a dispersive medium and a dispersing agent

wherein said dispersing agent is a polyether containing a polymer unit represented by the following general formula (1):

in the formula, R¹ represents a hydrogen atom or a hydrocarbon group of 1 to 22 carbon atoms;

R² represents —

(AO)m-R³;

R³ represents a hydrocarbon group of 1 to 22 carbon atoms which may optionally have a substituent;

A represents an alkylene group of 1 to 3 carbon atoms;

m represents an integer of 1 to 50; and

A groups which number m may be the same or different.

2. The stabilized dispersion magnetorheological fluid according to claim 1

wherein the dispersive medium is a hydrocarbon oil.

3. A stabilized dispersion magnetorheological fluid comprising a magnetic particle, a dispersive medium and a dispersing agent

wherein said dispersing agent is a polyether containing a polymer unit represented by the following general formula (1):

in the formula, R¹ represents a hydrogen atom or a hydrocarbon group of 1 to 22 carbon atoms;

when R¹ represents a hydrogen atom, R² represents a hydrocarbon group of 1 to 22 carbon atoms which may optionally have a substituent, or —

(AO)m-R³;

R³ represents a hydrocarbon group of 1 to 22 carbon atoms which may optionally have a substituent;

A represents an alkylene group of 1 to 3 carbon atoms;

m represents an integer of 1 to 50; and

A groups which number m may be the same or different, and when R¹ represents a hydrocarbon group of 1 to 22 carbon atoms, R² represents a hydrogen atom, a hydrocarbon group of 1 to 22 carbon atoms which may optionally have a substituent, or —

(AO)m-R³;

R³ represents a hydrocarbon group of 1 to 22 carbon atoms which may optionally have a substituent;

A represents an alkylene group of 1 to 3 carbon atoms;

m represents an integer of 1 to 50; and

A groups which number m may be the same or different,

and having a molecular weight of 10,000 to 100,000,000.

4. The stabilized dispersion magnetorheological fluid according to claim 3

wherein the dispersive medium is a hydrocarbon oil.