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:
Apr. 24, 2001
Filed:
Nov. 14, 1997
Gian Carlo Colombo, San Giorgio Su Legnano, IT;
ICMA San Giorgio S.p.A., San Giorgio Su Legnano, IT;
Abstract
A method of producing a composite stratiform material uses at least one extruder having a pair of co-rotating screws to co-extrude at least three layers, each layer having polypropylene and at least one filler. In a carrier layer the filler is particulate organic filler, and in first and second outer layers the filler is an inorganic filler. The co-extrusion provides for interfusion of the carrier layer with the outer layers at mutually opposite layer interfaces. The particulate organic filler of the carrier layer is either vegetabilic or wood which is extruded by a co-rotational extruder. The inorganic filler is introduced into at least one second extruder for extruding at least one of the outer layers.