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:
Apr. 14, 1992
Filed:
Nov. 20, 1990
Michael Hill, Ascot, GB;
Filter Materials Limited, New York, NY (US);
Abstract
A roller for use in fibrillating oriented films of polyolefin materials having a plurality of pins projecting from the surface of the roller. The pins are distributed in a plurality of rows spaced around the roller surface. The rows each contain about 25 to 34 pins per inch in a space-staggered relationship along two adjacent lines extending along the surface of the roller, either in a linear relationship inclined to a line parallel to the axis or rotation, or in a sinusoidal relationship with adjacent rows being in or out of phase. The roller is rotated and the film is advanced over the rotating roller surface for an arc length of contact of about 30 to 37 degrees to fibrillate the film. The ratio of the surface speed of the roller to the advancing film are controlled to a ratio between from about 1.8:1 to about 2.2:1.