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. 19, 1991
Filed:
Jul. 05, 1990
R Douglas Behr, Midland, MI (US);
DowBrands Inc., Indianapolis, IN (US);
Abstract
Disclosed are a process and apparatus for eliminating the problem of color contamination during product recycle in the manufacture of reclosable thermoplastic bags having zippers of a color different than that of the remainder of the bag. Process and apparatus for effecting same include extrusion of the colored thermoplastic material from a separate, smaller secondary extruder to avoid process shutdown during recycle, encapsulation of the colored thermoplastic material within the colorless flow melt to enhance transport of the colored flow melt, and placement of a dump valve between the secondary extruder and the feedblock to controllably interrupt the flow of the colored flow melt as desired. Further disclosed are an apparatus and process for effecting encapsulation of the colored flow melt.