Ralph A Franke

US Patent:

57889937, Aug 4, 1998

Filed:

Jun 6, 1997

Appl. No.:

8/870995

Inventors:

Michael Allen Bryner - Midlothian VA
Don M. Coates - Santa Fe NM
Michael Charles Davis - Richmond VA
Tom Edward Estep - Chesterfield VA
Ralph A. Franke - Richmond VA
Larry Ray Marshall - Chesterfield VA
Subhra K. Nath - Midlothian VA
Charles Wesley Starke - Richmond VA

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

B28B 500

US Classification:

425 722

Abstract:

A flash spin pack for a flash-spinning apparatus is provided in which the pack includes a spin mixture inlet, that communicates with a spin mixture passage, that discharges through a spinning orifice that opens into a slot defined by two opposing faces of the body of the spin pack. The slot is 0. 25 mm to 7 mm wide proximate the spinning orifice outlet, 0. 25 mm to 10 mm at the slot outlet, and the distance from the orifice outlet to the slot outlet is 1. 5 mm to 40 mm. The spin pack may have five or more spinning orifices that each discharge into a different slot so configured.

US Patent:

58339000, Nov 10, 1998

Filed:

Jul 23, 1996

Appl. No.:

8/685368

Inventors:

Ralph A. Franke - Richmond VA
Hyun S. Lim - Chesterfield VA
Larry Ray Marshall - Chesterfield VA

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

D01D 511

US Classification:

264103

Abstract:

This invention relates to a system and process for modifying the resulting properties of a flash spun plexifilamentary film-fibril web and spunbonded nonwoven sheets made from such webs. In particular, the system includes specifically designed letdown chamber arrangements wherein the solution of polymer and spin agent transitions from a single phase solution to a two phase solution in the letdown chamber prior to spinning at the spin orifice. The method comprises altering the configuration of the letdown chamber to alter the properties of the web and the sheet products made therefrom.

US Patent:

6070635, Jun 6, 2000

Filed:

Apr 17, 1998

Appl. No.:

9/062349

Inventors:

Ralph A. Franke - Richmond VA
Hyun S. Lim - Chesterfield NJ
Michael P. Milone - Elmer NJ
R. Gail Raty - Wilmington DE
Akhileswar G. Vaidyanathan - Hockessin DE

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

G01R 900

US Classification:

156378

Abstract:

This invention relates to improved sheet products and specifically to improved nonwoven sheet products made from highly oriented plexifilamentary film-fibril webs. The improved sheet products have high opacity and strength with a much wider range of porosity or Gurley Hill Porosity Values. In particular, sheet products made in accordance with the present invention have considerably higher Gurley Hill Porosity Values than similar weight sheet products subject to the same finishing treatments in accordance with prior known sheet materials. Similarly, sheet products made in accordance with the present invention can be made which have much lower Gurley Hill Porosity Values than prior sheet materials. The invention includes numerous methods and data characterizing the webs and sheets that form the improved sheet materials.

US Patent:

58636390, Jan 26, 1999

Filed:

Jul 23, 1996

Appl. No.:

8/685367

Inventors:

Ralph A. Franke - Richmond VA
Hyun S. Lim - Chesterfield VA
Larry Ray Marshall - Chesterfield VA
Michael P. Milone - Elmer NJ
R. Gail Raty - Wilmington DE
Akhileswar G. Vaidyanathan - Hockessin DE

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

B32B 2714

US Classification:

428198

Abstract:

This invention relates to improved sheet products and specifically to improved nonwoven sheet products made from highly oriented plexifilamentary film-fibril webs. The improved sheet products have high opacity and strength with a much wider range of porosity or Gurley Hill Porosity Values. In particular, sheet products made in accordance with the present invention have considerably higher Gurley Hill Porosity Values than similar weight sheet products subject to the same finishing treatments in accordance with prior known sheet materials. Similarly, sheet products made in accordance with the present invention can be made which have much lower Gurley Hill Porosity Values than prior sheet materials. The invention includes numerous methods and data characterizing the webs and sheets that form the improved sheet materials.