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. 18, 1992
Filed:
Dec. 04, 1991
Thomas R Clark, III, Hixson, TN (US);
Joseph A Cofer, Jr, Hixson, TN (US);
Alan R Mochel, Signal Mountain, TN (US);
E. I. Du Pont de Nemours and Comapny, Wilmington, DE (US);
Abstract
A polyamide yarn is disclosed which is at least about 85% by weight poly(.epsilon.-caproamide) and which has a relative viscosity of greater than 50, a tenacity of at least about 9.3 g/d, a dry heat shrinkage at 160.degree. C. of less than about 3 percent, a modulus of at least about 20 g/d, a toughness of at least about 240 g/d. %, a crystal perfection index of greater than about 82, and a long period spacing of greater than about 100 .ANG.. The process for making the yarn includes drawing of a feed yarn while heating to at least about 185.degree. C. in at least a final draw stage to a draw tension of at least 4.8 g/d, subsequently decreasing the tension while heating to at least about 185.degree. C. to produce a length decrease of between about 13.5 and about 30%, and cooling and packaging the yarn.