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:
May. 10, 1988
Filed:
Jul. 11, 1986
Heinrich Legters, Hardenberg, NL;
Bernhard Lodder, Hardenberg, NL;
Wavin B.V., , NL;
Abstract
A plastic bag of polyolefin material such as polyethylene, for packaging materials, comprising particles of less than 50 .mu.m, and a closed bag containing such materials and a foil material for such a bag. The foil wall of the bag is provided with venting apertures with smooth edges, obtained by laser radiation, having a maximum size of 50-100 .mu.m; the distance between the venting perforations is such that the tensile strength of the foil is substantially the same as the tensile strength of the similar non-perforated foil. In a low density polyethylene foil of a thickness of 130-190 .mu.m distance between the perforations of 80 .mu.m is more than 20 mm, in a linear low density polyethylene foil of about 50-110 .mu.m the perforation distance is at least 5 mm. The bag may consist of two perforated foil layers, the perforations being staggered with respect to each other.