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US3919377A Expired / Lapsed US ⏱️ 0.0 years remaining

Production of tapes and fibrous materials

Assignee: Smith and Nephew Polyfabrik Ltd
•
Filing: 1972-12-11
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Granted: 1975-11-11
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Expires: 1992-12-11
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Abstract

Abstract A hot melt film of cold-drawable thermoplastic polymer is fed through nip means between co-operating members at least one of which is a roller at a temperature below polymer melting point, the nip means being such as to produce shear in the film as between the two film surfaces, and including grooving means for at least one such surface, whereby a profiled sheet preferably having longitudinal grooves is produced of a nature which splits readily when stretched and may produce multi-filamentary yarn of crimped fibres.

Inventors

  • 👤 James Dow
  • 👤 Ronald Lloyd
  • 👤 Albert George Patchell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 18:42
CPC Classifications
B; B29; B29D; B29D99/00; B29D99/0078; B29C; B29C48/00; B29C48/03; B29C48/05; B29C48/07; B29C48/08; B29C48/12; B29C48/25; B29C48/88; B29C48/911; B29C48/9135; B29C48/914; B29C59/00; B29C59/02; B29C59/04; D; D01; D01D; D01D5/00; D01D5/42; D01D5/423; B29L; B29L2031/00; B29L2031/731; Y; Y10; Y10S; Y10S264/00; Y10S264/47

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 141 words
A METHOD OF PRODUCING A FIBROUS MATERIAL FROM A THERMOPLASTIC POLYMER, SAID METHOD CONSISTING ESSENTIALLY OF THE STEPS OF (1) MELTING SAID POLMER AND EXTRUDING THE SAME AS HOT CONTINUOUS MOLTEN FILM THEREBY DEFINING AN EXTRUSION DIRECTION IN THE FILM, (2) PASSINNG SAID HOT CONTINUOS MOLTEN FILMAS A PREFOMED FILM INT A FILM TREATING ZONE, (3) WITHIN SAID FILM TREAING ZONE APPLING A DRAGGING FORCE AROSS ON SURFACE OF SAID FREE, PREFOMED EXTRUDED FILM, (4) WITHIN SAID FILM TREATING ZONE SIMULTANEOUSLY FORMING LONGITUDINAL SPACED PARALLEL UNINTERRUPTED GROOVES IN AT LEAST ONE SURFACE OF SAID FILM, SAID GROOVES SEPARATED BYLONGITUDINAL RIBS, SAID GROOVES AND RIBS EXTENDIN IN THE DIREECTION OF EXTRUSION, (5) REMOVING THE GROOVED FILM FROM SAID FILM TREAING ZONE AND STRETCHING SAID FILM TO SPLIT INTO TAPES ALONG SAID GROOVES TO FORM FILAMENTS,AND (6) ALLOWING THE STRETCHED FILAMENTS TO RELAX.
Claim 2
Independent Claim 141 words
A METHOD OF PRODUCING A FIBROUS MATERIAL FROM A THERMOPLASTIC POLYMER, SAID METHOD CONSISTING ESSENTIALLY OF THE STEPS OF (1) MELTING SAID POLMER AND EXTRUDING THE SAME AS HOT CONTINUOUS MOLTEN FILM THEREBY DEFINING AN EXTRUSION DIRECTION IN THE FILM, (2) PASSINNG SAID HOT CONTINUOS MOLTEN FILMAS A PREFOMED FILM INT A FILM TREATING ZONE, (3) WITHIN SAID FILM TREAING ZONE APPLING A DRAGGING FORCE AROSS ON SURFACE OF SAID FREE, PREFOMED EXTRUDED FILM, (4) WITHIN SAID FILM TREATING ZONE SIMULTANEOUSLY FORMING LONGITUDINAL SPACED PARALLEL UNINTERRUPTED GROOVES IN AT LEAST ONE SURFACE OF SAID FILM, SAID GROOVES SEPARATED BYLONGITUDINAL RIBS, SAID GROOVES AND RIBS EXTENDIN IN THE DIREECTION OF EXTRUSION, (5) REMOVING THE GROOVED FILM FROM SAID FILM TREAING ZONE AND STRETCHING SAID FILM TO SPLIT INTO TAPES ALONG SAID GROOVES TO FORM FILAMENTS,AND (6) ALLOWING THE STRETCHED FILAMENTS TO RELAX.
Claim 3
Independent Claim 182 words
A method of producing a fibrous material from a thermoplastic polymer, said method consisting essentially of the steps of (1) melting said polymer and extruding the same as a hot continuous film thereby defining an extrusion direction in the film (2) passing the hot molten film as a free, preformed film into a film treatment zone (3) within said film treatment zone applying a drag force across one surface of said free, preformed extruded film which frictionally retards movement of the one surface relative to the other surface, (4) within said film treating zone extracting sufficient heat from said other surface of said free, preformed extruded film to solidify the film (5) within said film treating zone simultaneously forming spaced parallel longitudinally extending uninterrupted grooves in at least one surface of said film, said grooves being separated by longitudinal ribs, said grooves and ribs extending in the direction of extrusion, (6) removing the grooved film from said film treating zone, splitting the film into tapes by stretching and further splitting the tapes into filaments and (7) allowing the stretched filaments to relax.
Claim 4
Independent Claim 182 words
A method of producing a fibrous material from a thermoplastic polymer, said method consisting essentially of the steps of (1) melting said polymer and extruding the same as a hot continuous film thereby defining an extrusion direction in the film (2) passing the hot molten film as a free, preformed film into a film treatment zone (3) within said film treatment zone applying a drag force across one surface of said free, preformed extruded film which frictionally retards movement of the one surface relative to the other surface, (4) within said film treating zone extracting sufficient heat from said other surface of said free, preformed extruded film to solidify the film (5) within said film treating zone simultaneously forming spaced parallel longitudinally extending uninterrupted grooves in at least one surface of said film, said grooves being separated by longitudinal ribs, said grooves and ribs extending in the direction of extrusion, (6) removing the grooved film from said film treating zone, splitting the film into tapes by stretching and further splitting the tapes into filaments and (7) allowing the stretched filaments to relax.
Claim 5
Dependent Claim 20 words
The method of claim 1, where the film thickness at the bottom of the grooves is less than 10 microns.
Claim 6
Dependent Claim 14 words
The method of claim 1, where the degree of stretch is up to 2000%.
Claim 7
Dependent Claim 25 words
The method of claim 1, where the polymer is selected from the group consisting of polypropylene, polyethylene, polyamide, polyester, polyacrylonitriles, polyvinylidene chloride and blends thereof.
Claim 8
Dependent Claim 22 words
The method of claim 1, where the grooves are formed on the surface of the film where the dragging force is applied.
Claim 9
Dependent Claim 24 words
The method of claim 1 where the grooves are fOrmed on the surface of the film opposite from that where the heat is extracted.
Claim 10
Dependent Claim 18 words
The method of claim 6 where the dragging force is applied across the whole surface of the film.
Claim 11
Dependent Claim 15 words
The method of claim 6 where the dragging force is applied only within the grooves.
Claim 12
Independent Claim 188 words
The method of producing a fibrous material from a thermoplastic polymer, said method consisting essentially of the steps of (1) melting said polymer and extruding the same as a hot continuous molten film thereby defining an extrusion direction in the film (2) passing the hot continuous molten films as a free preformed film into a film treating zone (3) applying a shearing force to the opposed surfaces of the film so as to stress the film between said surfaces in planes parallel to said surfaces (4) within said film treating zone extracting sufficient heat from one surface of said free, preformed extruded film to solidify the film while the shearing stress continues to be applied thereto (5) within said film treating zone simultaneously forming longitudinally extending uninterrupted grooves in at least one surface of said film, the grooves being separated by longitudinally extending ribs, said grooves and ribs extending in the direction of extrusion (6) removing the grooved film from said film treating zone and stretching the film to split it into tapes and to split the tapes into filaments and (7) allowing the stretched filaments to relax.
Claim 13
Independent Claim 188 words
The method of producing a fibrous material from a thermoplastic polymer, said method consisting essentially of the steps of (1) melting said polymer and extruding the same as a hot continuous molten film thereby defining an extrusion direction in the film (2) passing the hot continuous molten films as a free preformed film into a film treating zone (3) applying a shearing force to the opposed surfaces of the film so as to stress the film between said surfaces in planes parallel to said surfaces (4) within said film treating zone extracting sufficient heat from one surface of said free, preformed extruded film to solidify the film while the shearing stress continues to be applied thereto (5) within said film treating zone simultaneously forming longitudinally extending uninterrupted grooves in at least one surface of said film, the grooves being separated by longitudinally extending ribs, said grooves and ribs extending in the direction of extrusion (6) removing the grooved film from said film treating zone and stretching the film to split it into tapes and to split the tapes into filaments and (7) allowing the stretched filaments to relax.
Claim 14
Independent Claim 185 words
The method of producing a bulky multifilament yarn containing inherently crimped fibers from a cold drawable thermoplastic polymer, said method consisting essentially of the steps of melting said polymer and extruding the same as a hot continuous molten film thereby defining an extrusion direction in the film, passing the hot continuous molten film as a preformed film into a film treating zone, applying a shearing force to the film parallel to the plane of its opposed surface across the entire width of the film, forming longitudinally extending uninterrupted grooves in at least one surface of the film, said grooves being separated by longitudinal ribs and extending in the direction of extrusion, subjecting one side of the film to a temperature lower than the other to effect cooling to produce a solid sheet in which the shearing stresses are imprisoned in the grooves and ribs in varying degrees in planes parallel to the surfaces, removing the grooved film from said film treatment zone and stretching the film to split it into tapes and to split the tapes into filaments and allowing the stretched filaments to relax.
Claim 15
Independent Claim 185 words
The method of producing a bulky multifilament yarn containing inherently crimped fibers from a cold drawable thermoplastic polymer, said method consisting essentially of the steps of melting said polymer and extruding the same as a hot continuous molten film thereby defining an extrusion direction in the film, passing the hot continuous molten film as a preformed film into a film treating zone, applying a shearing force to the film parallel to the plane of its opposed surface across the entire width of the film, forming longitudinally extending uninterrupted grooves in at least one surface of the film, said grooves being separated by longitudinal ribs and extending in the direction of extrusion, subjecting one side of the film to a temperature lower than the other to effect cooling to produce a solid sheet in which the shearing stresses are imprisoned in the grooves and ribs in varying degrees in planes parallel to the surfaces, removing the grooved film from said film treatment zone and stretching the film to split it into tapes and to split the tapes into filaments and allowing the stretched filaments to relax.
Claim 16
Dependent Claim 66 words
A method according to claim 10 comprising applying the shearing stresses to the molten film while moving it between a smooth surface at one side and a rolling surface on the other side and wherein the smooth surface is maintained at a temperature above the melting point of the polymer and the grooved surface is maintained at a temperature below the melting point of the polymer.
Claim 17
Dependent Claim 16 words
A method according to claim 12, wherein the rolling surface contains transversely thereof grooves and ribs.

References Cited (Backward Citations)

US2489951A Cited
US3746607A Cited
US3594870A Cited
US3608042A Cited
US3672013A Cited
US3641760A Cited
US3697636A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-11-10 1979-05-12 1979-11-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-11-10 1983-05-12 1983-11-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-11-10 1987-05-12 1987-11-11 $7700.00 Window Closed / Lapsed

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