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. 09, 2004
Filed:
Mar. 12, 2002
Gerhard Graab, Mannheim, DE;
Klaus Heckel, Gorxheimertal, DE;
Carl Freudenberg KG, Weinheim, DE;
Abstract
A floor covering made up of at least two layers bonded to one another, including a bottom layer ( ) of electrically conductive rubber arranged under a light-colored top layer ( ) of rubber, where the top layer ( ) is interrupted in partial areas distributed over its area in a pattern, and formed by electrically conductive rubber there. The top layer ( ) is produced from a powder ( ) of first particles ( ) that are light in color and made of electrically insulating rubber, as well as second particles ( ) embedded in it, which are made of electrically conductive, at least partially vulcanized rubber. The second particles ( ) have a diameter D, determined by screen analysis, that is at least as great as the thickness D of the top layer and, for practical purposes, not greater than the total of the thicknesses of the top layer and the bottom layer D . The first ( ) and the second ( ) particles are pressed together and to the bottom layer ( ), without pores, and bonded by vulcanization. At least one of the second particles ( ) is present per area unit of the floor covering of 31.7 cm , with the proviso that a maximum of 50% of the total area of the floor covering is taken up by the area of the second particles ( ).