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. 13, 2001
Filed:
Aug. 23, 1999
Kaneka Corporation, Osaka, JP;
Abstract
An extrusion foaming method for obtaining a styrene resin foam by introducing a blowing agent into the resin under pressure by which a foam having excellent heat insulating property and compressive strength can be produced with excellent stability using a blowing agent which is as environmentally safe as possible, characterized in that a foam is obtained by using a blowing agent comprising mainly less than 40% by weight and 5% by weight or more of an ether, and more than 60% by weight and not more than 95% by weight of a saturated hydrocarbon having 3 to 5 carbon atoms, based on the entire amount of the blowing agent, or as required, by using a blowing agent wherein a part of the saturated hydrocarbon in the foregoing blowing agent is replaced by a fluorinated hydrocarbon with concern for the environment, and preferably in that the ratio Z/X of cells constituting the foam wherein X is the average cell size in the direction of extrusion and Z is the average cell size in the direction of thickness is adjusted to 1 or less, preferably 0.8 or less by stretching the foam with heating after the extrusion.