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:
Aug. 31, 2004
Filed:
May. 20, 1998
Applicant:
Inventor:
Andreas Walder, Greifensee, CH;
Assignee:
Sulzer Chemtech AG, Winterhur, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B29C 4/422 ;
U.S. Cl.
CPC ...
B29C 4/422 ;
Abstract
Apparatus and method for the production of expandable plastics granulate (C). A plastics melt (A′) is impregnated by a fluid blowing agent (B), which is, at an elevated pressure within a predetermined pressure range, only partly soluble in the melt. The method comprises the following steps: 1. dispersion of the blowing agent in the melt, 2. retaining of the mixture within a predetermined pressure range for a predetermined retention time, 3. cooling of the melt impregnated by the blowing agent to a temperature which is several degrees Celsius above the solidification temperature of the melt, and 4. granulating the cooled mixture.