E.i. Dupont De Nemours and Company

Benjamin H Knox

Hans R Frankfort

Stephen B Johnson

Robert J Collins

Elmer E Most, Jr

James B Noe

Girish Anant Pai

David George Bennie

Joe Forrest London, Jr

Raymond L Boles

Arun Pal Aneja

Ralph W Nugent

Lee W Keene

Dennis R Schafluetzel

James P Bennett

Ronald E Steele

Frank H Overton

Francis J Malone, Jr

James H Drew

John P Hendrix, Jr

Gary D Milosovich

Paul G Zmick

Hans Rudolf Frankfort

David A Price, Sr

David Arthur Price

Hans, R Frankfort

A direct melt spinning process for providing high filament count fine filament polyester yarns having excellent mechanical quality and along-end uniformity and unitary interlace by spinning all the filaments of such high filament count yarn from a single spinneret. Such yarns may be used as direct-use yarns and as draw-feed yarns for preparing drawn flat yarns and draw-textured yarns.

Making high filament count fine filament polyester yarns

High filament count fine filament polyester yarns

Polyester mixed fine filament yarns having excellent mechanical quality and uniformity, and preferably with a balance of good dyeability and shrinkage, are prepared by a simplified direct spin-orientation process by selection of polymer and spinning conditions.

Polyester mixed yarns with fine filaments

Polyester filaments of high shrinkage and high shrinkage tension may be prepared by heat treatment of undrawn crystalline filaments of low shrinkage and shrinkage tension, and may be used for making polyester yarns of mixed shrinkage and bulky polyester yarns and fabrics therefrom.

Continuous filaments, yarns, and tows

A melt spinning process and the nylon hollow filaments and yarns made by such process which includes extruding molten nylon polymer having a relative viscosity (RV) of at least about 50 and a melting point (T.sub.M) of about 210.degree. C. to about 310.degree. C. from a spinneret capillary orifice with multiple orifice segments providing a total extrusion area (EA) and an extrusion void area (EVA) such that the fractional extrusion void content, defined by the ratio [EVA/EA] is about 0.6 to about 0.95, and the extent of melt attenuation, defined by the ratio [EVA/(dpf).sub.S ], is about 0.05 to about 1.5, in which (dpf).sub.S is the spun denier per filament, the (dpf).sub.S being selected such that the denier per filament at 25% elongation (dpf).sub.25 is about 0.5 to about 20 denier; withdrawing the multiple melt streams from the spinneret into a quench zone under conditions which causes substantially continuous self-coalescence of the multiple melt streams into spun filaments having at least one longitudinal void and a residual draw ratio (RDR) of less than 2.75; and stabilizing the spun hollow filaments to provide hollow filaments with a residual draw ratio (RDR) of about 1.2 to about 2.25.

Hollow nylon filaments and yarns

Hollow nylon filaments

A post-coalescence melt-spinning process for preparing fine undrawn hollow polyester filaments having excellent mechanical quality and uniformity at high speeds (2-5 km/min) involving selection of polymer viscosity and spinning conditions, whereby the void content of the resulting new undrawn filaments is essentially maintained or increased on cold-drawing or hot-drawing with or without post heat treatment, and the new fine hollow polyester filaments obtained thereby.

Process for polyester fine hollow filaments

Hollow polyester undrawn filaments having excellent mechanical quality and uniformity are prepared by a simplified post-coalescence melt spinning process at speeds of e.g. 2-5 km/min by selection of polymer and spinning conditions whereby the void content of the undrawn filaments can be essentially maintained or even increased when drawn cold or hot, with or without post heat-treatment.

Continuous hollow filaments, yarns, and tows

Process of making spin-oriented, biconstituent filaments

Process of making fine polyester hollow filaments

A melt spinning process and the nylon hollow filaments and yarns made by such process which includes extruding molten nylon polymer having a relative viscosity (RV) of at least about 50 and a melting point (T.sub.M) of about 210.degree. C. to about 310.degree. C. from a spinneret capillary orifice with multiple orifice segments providing a total extrusion area (EA) and an extrusion void area (EVA) such that the fractional extrusion void content, defined by the ratio [EVA/EA] is about 0.6 to about 0.95, and the extent of melt attenuation, defined by the ratio [EVA/(dpf).sub.S ], is about 0.05 to about 1.5, in which (dpf).sub.S is the spun denier per filament, the (dpf).sub.S being selected such that the denier per filament at 25% elongation (dpf).sub.25 is about 0.5 to about 20 denier; withdrawing the multiple melt streams from the spinneret into a quench zone under conditions which causes substantially continous self-coalescence of the multiple melt streams into spun filaments having at least one longitudinal void and a residual draw ratio (RDR) of less than 2.75; and stabilizing the spun hollow filaments to provide hollow filaments with a residual draw ratio (RDR) of about 1.2 to about 2.25.

Process for making hollow nylon filaments

Flat continuous multifilament nylon apparel yarns suitable for critical dye applications and a process for making such yarns are provided. The process for making the yarns includes spinning nylon polymer with a relative viscosity between about 35 and about 80 and stabilizing to make a feed yarn. The withdrawal speed in spinning is sufficiently high that highly uniform feed yarns are provided. In the process, feed yarn is drawn and subsequently relaxed, preferably in the form of a warp of yarns, so that the resulting drawn yarns have properties suitable for use as flat yarns and have excellent dye uniformity with large molecule acid dyes.

Nylon flat yarns

Process of making polyester mixed yarns with fine filaments

Polyester fine filaments having excellent mechanical quality and uniformity, and preferably with a balance of good dyeability and shrinkage, are prepared by a simplified direct spin-orientation process by selection of polymer viscosity and spinning conditions, followed by drawing and/or bulking.

Process for preparing polyester fine filaments

Process of making spin-oriented polyester filaments

Growing community of inventors

Wilmington, DE, United States of America

Benjamin H Knox