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:
Jan. 25, 1994
Filed:
Oct. 13, 1992
Japan Styrene Paper Corporation, Tokyo, JP;
Abstract
A foamed polyolefin sheet is formed by extruding a molten polyolefin resin, which contains a blowing agent, into a low-pressure zone through an annular die provided at an end of the extruder to form a foamed tubular body, bringing the foamed tubular body into contact with a peripheral surface of a cylindrical cooling device to cool the foamed tubular body and then slitting the thus-cooled foamed tubular body and then slitting the thus-cooled foamed tubular body in the direction of extrusion to open same. The cylindrical cooling device is divided into an upstream section and at least one other spaced downstream sections. The internal pressure of the foamed tubular body is increased to from about 5.times.10.sup.-4 to 3.times.10.sup.-2 kg/cm.sup.2 (G) between the die and the upstream section of the cylindrical cooling device and also between at least two adjacent sections of the cylindrical cooling device to apply tension to the foamed tubular body at the inner wall and prevent the formation of corrugations.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile