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. 03, 1981
Filed:
Feb. 12, 1980
Hung H Yang, Richmond, VA (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A process for preparing high strength, high modulus aromatic polyamide filaments by extruding an acid solution containing at least 30 g. per 100 acid of an aromatic polyamide having an inherent viscosity of at least 4 and chain extending bonds which are either coaxial or parallel and oppositely directed through a layer of inert noncoagulating fluid into a coagulating bath and then through a spin tube along with overflowing coagulating liquid is improved by jetting additional coagulating liquid symmetrically about the filaments in a downward direction forming an angle .theta. or 0.degree. to 85.degree. with respect to the filaments within 2.0 milliseconds from the time the filaments enter the spin tube, the flow rates of both the jetted and overflowing coagulating liquid being maintained at a constant rate such that their momentum ratio .phi. is from 0.5 to 6.0 and the mass flow rate of total coagulating liquid is from 70 to 200 times the mass flow rate of the filaments.