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:
Feb. 15, 1994
Filed:
Mar. 20, 1991
Sekisui Kaseihin Kogyo Kabushiki Kaisha, Nara, JP;
Abstract
A polypropylene resin foamed sheet for thermoforming having compounded therein an inorganic fine powder is disclosed. The sheet contains 10 to 50% by weight of the inorganic fine powder, has a density of 0.2 to 1.2 g/cm and a thickness of 0.2 to 3 mm and having a percent shrinkage of 5 to 30% in each of the longitudinal and crosswise directions on heating at 190.degree. C. for 30 minutes, with the ratio of a residual rate in the longitudinal direction to that in the crosswise direction being from 1:0.7 to 1:1.1. The sheet is produced by extruding and foaming a compounded resin from a ring die of an extruder, and taking off the extruded tubular foamed sheet along a cylindrical drum whose diameter is 2.0 to 3.0 times that of said ring die.