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. 01, 1988
Filed:
May. 06, 1986
Applicant:
Inventor:
William T Windley, Seaford, DE (US);
Assignee:
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
D01F / ;
U.S. Cl.
CPC ...
264 53 ; 264211 ; 2642106 ; 2642108 ; 26421112 ; 521 60 ; 521 79 ; 521 98 ;
Abstract
A fiber having 1/2-50% substantially gas-filled and essentially all closed cells having a diameter of 0.2-25 microns and a length to diameter ratio of greater than 500 is disclosed. The fiber is made by mixing a fluorocarbon blowing agent into molten polymer, shearing the polymer at a high shear rate, extruding the polymer in a spinneret capillary at a low jet velocity and a low capillary entrance pressure and drawing down the polymer at a total extension greater than 1000.