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:
Mar. 24, 1987
Filed:
Dec. 05, 1985
Gunther Crass, Taunusstein, DE;
Siegfried Janocha, Wiesbaden, DE;
Lothar Bothe, Mainz-Gonsenheim, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
A sealable, opaque polyolefinic multilayer film composed of a polypropylene base layer, a non-sealable surface layer, and a sealable surface layer, and process therefor. The sealable surface layer has a low minimum sealing temperature and is made from a copolymer of propylene and ethylene or butene-1 units and/or a terpolymer of ethylene, propylene and butene-1 units. The non-sealable layer is a combination of a propylene homopolymer and a slip agent. The base layer contains an additive which is incompatible with polypropylene. The process includes stretching of the film, and during the stretching step, the polymer matrix is torn open around the additive particles to form vacuoles which give the base layer a degree of opacity.