The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 20, 1984
Filed:
Mar. 14, 1983
James E Stangroom, Castleton, GB;
Ian Harness, Sheffield, GB;
The National Research Development Corp., London, GB;
Abstract
An electroviscous (EV) fluid composition whose fluid properties are altered in the presence of an electric field comprises water-containing particles of a phenol-formaldehyde polymer dispersed in a non-conducting liquid. The composition, selected from the broad range of fluid compositions of UK Pat. No. 1570234, possesses improved fluid properties combined with markedly reduced electrical conductivity, and is thus more suitable for use in applications such as at the interface between electronics and power hydraulics for example. In a preferred embodiment of the present invention the polymer comprises the dilithium salt of 2,2', 4,4' tetrahydroxybenzophenone condensed with formaldehyde, dispersed at 30% V/V in a mixture of brominated diphenyl methane (BDM) liquid components having the averaged formula C.sub.6 H.sub.4 Br.CH.sub.2.C.sub.6 H.sub.5.