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:
Dec. 25, 1984
Filed:
Sep. 17, 1982
Tokio Okada, Tokyo, JP;
Shigezo Kojima, Tokyo, JP;
Haruhisa Tani, Tokyo, JP;
Kazuhiko Kurihara, Tokyo, JP;
Hirosi Yazawa, Kunitachi, JP;
Nippon Petrochemicals Co Ltd., Chiyoda, JP;
Polymer Processing Research Institute Ltd., Tokyo, JP;
Abstract
A method of slitting a continuous thermoplastic film comprises advancing the film longitudinally at a first speed along a peripheral surface of a roll rotating at a peripheral speed equal to or slightly greater than that of the film, and slitting the film while being advanced by pressing cutting edges of a rotating cutter against the peripheral surface of the roll. In order to prevent the cutting edges from being worn out and to form slits of uniform size and shape, the peripheral surface comprises an elastic layer of polymeric material, the cutting edges are heated above a temperature at which the film starts melting, the film and the elastic surface layer are cooled along their contacting surfaces with a cooling liquid, and the cutting edges are rotated at substantially the same peripheral speed as the roll. The invention also includes an apparatus for carrying out the method.