E.i. Dupont De Nemours and Company

Hans R Frankfort

Benjamin H Knox

Stephen B Johnson

Robert J Collins

Elmer E Most, Jr

Girish Anant Pai

David George Bennie

Joe Forrest London, Jr

Arun Pal Aneja

George Vassilatos

James B Noe

Gregory Eugene Sweet

Young D T Nguyen

A melt spinning apparatus for spinning continuous polymeric filaments including a first stage gas inlet chamber adapted to be located below a spinneret and optionally a second stage gas inlet chamber located below the first stage gas inlet chamber. The gas inlet chambers supply gas to the filaments to control the temperature of the filaments. The melt spinning apparatus also includes a tube located below the second stage gas inlet chamber for surrounding the filaments as they cool. The tube may include an interior wall having a converging section, optionally followed by a diverging section.

Apparatus and process for spinning polymeric filaments

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

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

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.

Process of making spin-oriented, biconstituent filaments

Process of making fine polyester hollow filaments

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

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.

Polyester fine filaments

A process of making mixed shrinkage yarn, including drawing, especially cold-drawing, or hot-drawing or other heat-treatments of spin-oriented crystalline polyester filaments, and particularly polyester feed yarns, that have been prepared by spinning at speeds of, e.g., 4 km/min, and have low shrinkage and no natural draw ratio in the conventional sense, that provides useful technique for obtaining uniform drawn filaments of desired denier and of differential shrinkage, and thereby provides improved flexibility to obtain filaments and yarns of mixed shrinkage.

Process of making mixed shrinkage yarn

Poly(ethylene terephthalate) filaments of enhanced dyeability, low boil-off shrinkage (even in as-spun condition), good thermal stability over a large temperature range; and useful as texturing feed yarns and/or as hard yarns requiring no further drawing are prepared by spinning at extremely high speeds, and are characterized by a long period spacing above 300 A in their as-spun condition, and, whether in as-spun condition or after heat-treatment, by a low skin-core value as measured by a differential birefringence in relation to their stress measured at 20% extension (which correlates approximately with the spinning speed), a large crystal size, and low amorphous orientation. The continuous filament yarns may be draw-textured to provide textured yarns which also show enhanced dyeability. The staple fiber yarns also have very useful properties as compared with conventional staple yarns. A preferred process of spinning at these extremely high speeds is characterized by the use of a spinneret with capillary-dimensions that produce high shear as the polyester is extruded, and is applicable also to copolyesters, whose filaments show a similar low skin-core in relation to their stress at 20% extension, the precise values for copolymers being different from the relationship for poly(ethylene terephthalate).

Growing community of inventors

Kinston, NC, United States of America

Hans R Frankfort