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:
Oct. 28, 2003
Filed:
Jan. 31, 2001
Thomas A. J. Schweiger, Richmond, VA (US);
E. I. du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A process for flash-spinning a web of plexifilamentary film-fibril strands of synthetic fiber-forming polymer and laying down the web to form a nonwoven batt material therefrom is provided. The process includes the the step of generating a spin fluid consisting essentially of synthetic fiber-forming polymer and a spin agent, wherein the spin agent is comprised of at least 80% by weight, based on the total weight of the spin agent, of hydrocarbons comprised substantially exclusively of carbon and hydrogen atoms. The hydrocarbons are comprised of at least 25% by weight of unsaturated hydrocarbons having 4-8 carbon atoms. The process further includes the steps of flash-spinning the spin fluid at a pressure that is greater than the autogenous pressure of the spin fluid into a spin cell maintained at lower pressure to form a web of plexifilamentary film-fibril strands of said synthetic fiber-forming polymer, applying an electrostatic charge to the web by passing the web through an electric corona, and laying the web onto a grounded surface to form a batt of plexifilamentary film-fibril strands that is suitable for being consolidated into a sheet.