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US4013744A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the manufacture of fibrids of thermoplastics materials

Assignee: BASF SE
•
Filing: 1973-02-26
•
Granted: 1977-03-22
•
Expires: 1993-02-26
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Abstract

Abstract A process for the manufacture of fibrids of thermoplastics materials by extruding molten thermoplastics through dies and breaking up the extrudate into fibers by means of a liquid medium causing shear stresses within a small volume, to which end the extrudate is passed to a zone of high energy dissipation so that it is completely divided up into fibers of the desired size in a single pass.

Inventors

  • 👤 Heribert Kuerten
  • 👤 Otto Nagel
  • 👤 Richard Sinn
  • 👤 Werner Weinle
  • 👤 Peter Engler

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 13:07
CPC Classifications
D; D01; D01D; D01D5/00; D01D5/40

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 185 words
A process for the manufacture of fibrids of a thermoplastic polymer material which comprises extruding strands of molten thermoplastic polymer material through orifices of die means into a shear gradient zone between and created by a propulsive jet of liquid flowing from a nozzle adjacent said die means at a velocity of 10-100 meters per second and flowing in the same direction as said strands and a slower moving liquid body entrained by the propulsive jet and located in a liquid-filled zone surrounding said orifices and the propulsive jet, passing said strands, the propulsive jet and the entrained liquid immediately and directly into and through a tubular impulse exchange zone having a mean diameter of two to 20 times the diameter of said nozzle of said propulsive jet and a length of 2-30 times its hydraulic diameter to provide shear stresses acting on said strands within said impulse exchange zone, and causing said strands of molten thermoplastic polymer to solidfy by the cooling of said melt by said liquid and to be broken up into fibrids by said shear stresses within said impulse exchange zone.
Claim 2
Dependent Claim 185 words
A process for the manufacture of fibrids of a thermoplastic polymer material which comprises extruding strands of molten thermoplastic polymer material through orifices of die means into a shear gradient zone between and created by a propulsive jet of liquid flowing from a nozzle adjacent said die means at a velocity of 10-100 meters per second and flowing in the same direction as said strands and a slower moving liquid body entrained by the propulsive jet and located in a liquid-filled zone surrounding said orifices and the propulsive jet, passing said strands, the propulsive jet and the entrained liquid immediately and directly into and through a tubular impulse exchange zone having a mean diameter of two to 20 times the diameter of said nozzle of said propulsive jet and a length of 2-30 times its hydraulic diameter to provide shear stresses acting on said strands within said impulse exchange zone, and causing said strands of molten thermoplastic polymer to solidfy by the cooling of said melt by said liquid and to be broken up into fibrids by said shear stresses within said impulse exchange zone.
Claim 3
Dependent Claim 17 words
A process as claimed in claim 1 wherein said tubular impulse exchange zone is a cylindrical tube.
Claim 4
Dependent Claim 26 words
A process as claimed in claim 1 wherein said tubular impulse exchange zone is located in said liquid filled zone and is immersed in the liquid.
Claim 5
Dependent Claim 21 words
A process as claimed in claim 1 wherein said tubular impulse exchange zone is immediately downstream of said liquid filled zone.
Claim 6
Dependent Claim 28 words
A process as claimed in claim 1 wherein the thermoplastic polymer material is a member selected from the group consisting of polyolefins, waxes thereof and extended waxes thereof.
Claim 7
Dependent Claim 21 words
A process as claimed in claim 1 wherein said propulsive jet nozzle is disposed coaxially within a circle of said orifices.
Claim 8
Dependent Claim 14 words
A process as claimed in claim 1 wherein the propulsive jet liquid is water.

References Cited (Backward Citations)

US3042970A Cited
US3389194A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-03-21 1980-09-20 1981-03-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-03-21 1984-09-20 1985-03-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-03-21 1988-09-20 1989-03-22 $7700.00 Window Closed / Lapsed

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