E.i. Dupont De Nemours and Company

Verdex Technologies, Inc.

Larry Ray Marshall

Robert Anthony Marin

Jack Eugene Armantrout

Hyun Sung Lim

Tao Huang

Michael Allen Bryner

Lewis E Manring

Ralph A Franke

John R Moore

Barbara Klimowicz O'Rourke

Neal Pfeiffenberger

Amanda Dawn Miller

Don Mayo Coates

Akhileswar G Vaidyanathan

Gary S Huvard

Marios Avgousti

Wazir Nobbee

Mark David Wetzel

Michael Patrick Milone

Tom Edward Estep

Charles Wesley Starke

R Gail Raty

Michael Charles Davis

Scott Yembrick

William H Dunn

Jennifer Marie Warren

James M Oconnor

Subhra K Nath

Tim Mueller

Lewis Edward Manring

James M O'CONNOR

A method is disclosed for producing a coform fibrous materials comprising the steps of supplying a first fiber forming stream comprising a first phase comprising a polymer melt and a second phase comprising a pressurized gas to a two-phase flow nozzle, supplying a separate second stream containing at least one secondary material to the two-phase flow nozzle, combining the first fiber forming stream and the second stream to form a composite fiber forming stream and fibrillating the composite fiber forming stream into a coform fibrous web. Superabsorbent and filtration coform fibrous materials for filtration and produced using the method are also disclosed.

Coform fibrous materials and method for making same

The invention relates to a process for forming fibers from a spinning solution utilizing a high speed rotary sprayer. The fibers can be collected into a uniform web for selective barrier end uses. Fibers with an average fiber diameter of less that 1,000 nm can be produced.

Solution spun fiber process

The disclosure relates to an apparatus and method for producing nanofibers and non-woven nanofibrous materials from polymer melts, liquids and particles using a two-phase flow nozzle. The process comprises supplying a first phase comprising a polymer melt and a second phase comprising a pressurized gas stream to a two-phase flow nozzle; injecting the polymer melt and the pressurized gas stream into a mixing chamber within the two-phase flow nozzle wherein the mixing chamber combines the polymer flow and pressurized gas into a two-phase flow; distributing the two-phase flow uniformly to a converging channel terminating into an channel exit wherein the converging channel accelerates the two-phase flow creating a polymeric film along the surface of the converging channel and fibrillating the polymeric film at the channel exit of the converging channel in the form of a plurality of nanofibers.

Process and apparatus for producing nanofibers using a two phase flow nozzle

A process and apparatus for forming nanofibers from a spinning melt utilizing a high speed rotating distribution disc. The fibers can be collected into a uniform web for selective barrier end uses. Fibers with an average fiber diameter of less that 1,000 nm can be produced.

Production of nanofibers by melt spinning

A fluidized mixture is issued from a nozzle comprising a fan jet at the outlet, causing the mixture to spread as it is issued. The issued material is collected on a moving collection surface located a distance of between 0.25 and 13 cm from the outlet of the nozzle, prior to the onset of large scale turbulence in the fluid jet. The resulting product has good basis weight uniformity.

Process for forming uniformly distributed material

This invention relates to improved plexifilamentary sheet material useful in protective apparel and filtration media, which material is comprised of substantially continuous polyethylene plexifilamentary fiber strands and has a Frazier Permeability, normalized to 1.0 oz/ydbasis weight, of at least 2 cfm/ft.

Flash-spun sheet material

A thin, uniform membrane comprising polymeric fibrils or a combination of fibrils and particles, wherein the fibrils have randomly convoluted cross-sections, and a process for making the membrane are disclosed. The membrane may be on the surface of a substrate as part of a composite sheet, or as a stand-alone structure.

Rotary process for forming uniform material

A process is provided for issuing material from a nozzle in a rotor rotating at a given rotational speed wherein the material is issued by way of a fluid jet. The material can be collected on a collector concentric to the rotor. The collector can be a flexible belt moving in the axial direction of the rotor. The collected material can take the form of discrete particles, fibers, plexifilamentary web, discrete fibrils or a membrane.

This invention relates to improved sheets of flash-spun plexifilamentary film-fibrils useful in fluid microfiltration and sterile packaging. The sheet material suitable for use in microfiltration of liquids has a permeability that causes a pressure drop of less than 21 kPa at a water flow rate per unit area of 12.55 ml/min/cm.sup.2, and that has a filtration efficiency of 99% of dust particulates in the size range of 1 to 2 microns suspended in a stream of distilled water pumped through the sheet material at a pressure differential of 207 kPa. The sheet material suitable for use in sterile packaging that has a Gurley Hill Porosity of less than 15 seconds and a bacteria spore log reduction value of at least 2.5.

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.

Nonwoven sheet products made from plexifilamentary film fibril webs

Growing community of inventors

Chesterfield, VA, United States of America

Larry Ray Marshall