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:
Oct. 26, 1999
Filed:
Mar. 24, 1998
Gary A Shreve, Austin, TX (US);
Nanayakkara Liyanage Somasiri, Austin, TX (US);
Justine Anne Mooney, Austin, TX (US);
Alan George Hulme-Lowe, Austin, TX (US);
Curtis Roy Guilbert, Austin, TX (US);
3M Innovative Properties Company, Saint Paul, MN (US);
Abstract
A method of altering a portion of the semiconductive layer of an electric power cable, to increase its resistance so as to render it electrically insulative. The semiconductive layer is loaded with carbon powder which forms chains to provide conductive pathways through the layer. By introducing an intercalant into the semiconductive layer, which causes the layer to swell, the conductive pathways are interrupted and the material is rendered insulative (>10.sup.4 .OMEGA.-cm). The intercalant may be a polymerizable material with a curing agent which is cured in situ, i.e., without removing the semiconductive layer from the cable. By this method, flashover to the semiconductive layer at a cable splice or termination may be prevented without requiring tedious removal of the exposed portion of the semiconductive layer. The method is usable with both strippable and coextruded semiconductive layers.