Filaments Patents (Class 264/178F)
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Patent number: 6127506Abstract: A process for melt spinning spandex, utilizing a polyurethaneurea polymer prepared from a purified capped glycol, linear aliphatic diamines and a monoamine chain terminator, is provided.Type: GrantFiled: February 19, 1999Date of Patent: October 3, 2000Assignee: E. I. du Pont de Nemours and CompanyInventor: Robin N. Greene
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Patent number: 6094769Abstract: The invention is directed to a bristle (1) for a toothbrush, in particular for an electric toothbrush, which is comprised of a monofilament (2) made of plastic. The monofilament (2) is of a non-circular cross-section, is twisted about its longitudinal axis, and is fixed as a result of the action of chemical agents. In this manner, the bristle (1) is provided with a three-dimensionally structured surface which effects an improved cleaning action, in particular with regard to the removal of plaque.Type: GrantFiled: April 1, 1999Date of Patent: August 1, 2000Assignee: Braun GmbHInventors: Georges Driesen, Ahmet Cem Firatli, Rainer Hans, Norbert Schaefer, Armin Schwarz-Hartmann
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Patent number: 6036895Abstract: A continuous process and apparatus for the production of melt-spun monofilaments having a diameter of 60 .mu.m to 2500 .mu.m from fiber-forming polymers, wherein the polymer melt is spun into air from a spinning head, laterally quenched in a spinning cabinet with a defined air velocity profile and then cooled in a liquid bath.Type: GrantFiled: June 25, 1998Date of Patent: March 14, 2000Assignee: Bayer Faser GmbHInventors: Jurgen Budenbender, Eckhard Gartner
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Patent number: 6017474Abstract: Formulation polymer dopes and development of processes for preparing asymmetric polyethersulfone hollow fiber membranes for gas separation are provided. Polyethersulfone hollow fiber membranes which exhibit improved gas permeability and selectivity have been produced from a formulated polymer dope containing N-methyl-2-pyrrolidone (NMP) and suitable nonsolvent-additives (NSA). The nonsolvent-additives are water and the mixture of ethanol and water. The dopes were tailored to be close to the point of phase separation, and have moderate polymer concentration with moderate viscosity. The hollow fibers were spun by the dry-wet phase inversion processes using water as both the internal and external coagulant. The dried hollow fibers are then coated with silicone rubber, a highly permeable material and the coated hollow fiber membranes exhibit excellent permeability and selectivity compared to those of the state-of-the-art polyethersulfone membranes.Type: GrantFiled: June 19, 1998Date of Patent: January 25, 2000Assignee: National University of SingaporeInventors: Wah Koon Teo, Kang Li, Dongliang Wang
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Patent number: 6015516Abstract: A process for forming ultrathin dense-layer asymmetric hollow fiber membranes with a dense layer of less than 500 .ANG. from a binary solution system comprising a polymer and a solvent. In this process, the spinning polymeric solution has a high viscosity and exhibits chain entanglement at the spinning temperature. The solubility parameter difference between the bore fluid and the spinning dope is less than 2.5 (cal/cm.sup.3).sup.0.5 and the volume ratio of bore-fluid flow rate to the dope flow rate is between 0.45 to 0.75. The dope is wet-spun into hollow fibers using water as external coagulant. The ultrathin dense-layer asymmetric hollow fiber membranes are suitable for air and other gas separations.Type: GrantFiled: June 19, 1998Date of Patent: January 18, 2000Assignee: National University of SingaporeInventors: Tai-Shung Chung, Xudong Hu, Soo Khean Teoh
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Patent number: 5961906Abstract: The use of dispersions of polyurethanes containing urea groups and based on selected starting materials, optionally via the intermediate stage of granules obtained by spray drying the dispersions, for the production of fully biodegradable shaped bodies.Type: GrantFiled: November 4, 1997Date of Patent: October 5, 1999Assignee: Bayer AktiengesellschaftInventors: Hanns-Peter Muller, Jochen Kalbe, Rainhard Koch
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Patent number: 5952434Abstract: The invention relates to synthetic yarns spun from suophuric acid anistropic solutions of rigid aromatic polyamides blended with aliphatic polyamides. Disclosed is a spinning dope composition comprising an aromatic polyamide, an aliphatic polyamide and concentrated sulphuric acid, wherein at least one of the aromatic and aliphatic plyamides is a copolymer composed of two aromatic and two aliphatic homopolymer units, respectiveyl; the aromatic copolymer having the formula: ?.paren open-st.(HN C.sub.6 H.sub.4 --HH CO C.sub.6 H.sub.4 CO.paren close-st.u.paren open-st.NH C.sub.6 H.sub.4 NH CONH C.sub.6 H.sub.4 NH CO C.sub.6 H.sub.4 CO.paren close-st.w!, wherein u=75-95 wt. % and w=5-25 wt. % and the aliphatic copolymer has the formula ?.paren open-st.HN(CH.sub.2).sub.6 --NHCO(CH.sub.2).sub.4 CO.paren close-st.n.paren open-st.HN(CH.sub.2).sub.5 CO.paren close-st.m wherein n=95-50 wt. % and m=5-50 wt. %.Type: GrantFiled: January 9, 1998Date of Patent: September 14, 1999Assignee: Vserossiisky Nauchno-Issledovatedlsky Institut Polimernykh Volokon S Opytnym Zavodom (Vniipv)Inventors: Tatyana Sergeevna Sokolova, Vera Dmitrievna Kalmykova, Vera Nikolaevna Sheptukhina, Ljudmila Dmitrievna Serova, Tatyana Andreevna Rozhdestvenskaya, Vladimir Nikolaevich Kiya-Oglu, Alexandra Vasilievna Volokhina, Ljubov Yakovlevna Tikanova, Georgy Ivanovich Kudryavtsev, deceased
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Patent number: 5938999Abstract: A wet-spinning fiber process which controls the micro-structure of the wepun fiber by varying the non-solvent/solvent miscibility and precipitation strength.Type: GrantFiled: February 14, 1997Date of Patent: August 17, 1999Assignee: The United States of America as represented by the Secretary of the NavyInventors: Leonard J. Buckley, Mark Eashoo
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Patent number: 5922259Abstract: There is provided a cord of twisted polybenzazole fibers, which has a tenacity of 35 g/d or higher and an elastic modulus of 800 g/d or higher. The cord has not only remarkably improved fatigue resistance but also excellent mechanical characteristics at a high level that has not been achieved so far. Therefore, it can attain the weight reduction of composite materials, particularly in the field of reinforced rubber materials, and can also make a great contribution to the energy saving.Type: GrantFiled: July 18, 1996Date of Patent: July 13, 1999Assignee: Toyo Boseki Kabushiki KaishaInventors: Yukinari Okuyama, Hiroshi Hirahata, Kazuyuki Yabuki
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Patent number: 5911930Abstract: A fiber containing an organic acid salt of an intrinsically conductive polymer distributed throughout a matrix polymer along with a method for providing such fibers by spinning a solution which includes an organic acid salt of an intrinsically conductive polymer, a matrix polymer and a spinning solvent into a coagulation bath including a nonsolvent for both the organic acid salt of an intrinsically conductive polymer and the matrix polymer. The intrinsically conductive polymer-containing fibers typically have electrical conductivities below about 10.sup.-5 S/cm.Type: GrantFiled: August 25, 1997Date of Patent: June 15, 1999Assignee: Monsanto CompanyInventors: Patrick J. Kinlen, Bruce G. Frushour
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Patent number: 5910274Abstract: Improved anisotropic fluid separation membranes are prepared from blends of polymers with surface energy differences. The membranes are formulated by processes wherein low surface energy polymer with desirable fluid separation and permeation characteristics is preferentially concentrated in the surface discriminating layer of the membrane.Type: GrantFiled: September 4, 1997Date of Patent: June 8, 1999Assignee: Praxair Technology, Inc.Inventors: James Timothy Macheras, Benjamin Bikson, Joyce Katz Nelson
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Patent number: 5840828Abstract: A polyimide fiber having textile physical property characteristics and the process of melt extruding same from a polyimide powder. Polyimide powder formed as the reaction product of the monomers 3,4'-ODA and ODPA, and endcapped with phthalic anhydride to control the molecular weight thereof, is melt extruded in the temperature range of 340.degree. C. to 360.degree. C. and at heights of 100.5 inches, 209 inches and 364.5 inches. The fibers obtained have a diameter in the range of 0.0068 inch to 0.0147 inch; a mean tensile strength in the range of 15.6 to 23.1 ksi; a mean modulus of 406 to 465 ksi; and a mean elongation in the range of 14 to 103%.Type: GrantFiled: May 7, 1997Date of Patent: November 24, 1998Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: Terry L. St. Clair, Catharine C. Fay, Dennis C. Working
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Patent number: 5824767Abstract: A process for improving the processability of poly(arylene sulfide) in melt spinning operations by treatment with a barium-containing compound and, optionally, a lubricant is disclosed.Type: GrantFiled: July 8, 1996Date of Patent: October 20, 1998Assignee: Hoechst Celanese CorporationInventors: Balaram B. Gupta, Andrew B. Auerbach, Barrie L. Davies
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Patent number: 5804120Abstract: Celluloe extrudates can be made from an optically anisotropic solution containing 94-100 wt % of: cellulose; phosphoric acid and/or its anhydrides; and water by extruding the solution, coagulating the formed extrudates, and then aftertreating those extrudates so that they have a degree of acidity which at least equals 7. Fibres obtained by such a process possess particularly good thermal stability and are suitable for use as a reinforcing material.Type: GrantFiled: February 19, 1997Date of Patent: September 8, 1998Assignee: Akzo Nobel N.V.Inventors: Hanneke Boerstoel, Marco Ypma
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Patent number: 5762846Abstract: A process for spinning a fully water washed fluorinated olefinic polymer intermediate fiber structure from a mixture of an aqueous dispersion of particles of the fluorinated olefinic polymer and a solution of a cellulosic ether.Type: GrantFiled: December 20, 1996Date of Patent: June 9, 1998Assignee: E. I. du Pont de Nemours and CompanyInventors: Nicole Lee Blankenbeckler, Joseph Michael Donckers, II, Warren Francis Knoff
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Patent number: 5762798Abstract: An asymmetrical, microporous, hollow fiber membrane is made from a polymeric dope mixture of polysulfone and polyvinyl pyrrolidone dissolved in an aprotic solvent. The physical morphology of the hollow fiber membrane, i.e., the asymmetric microporous wall, is rapidly formed by passing the polymeric dope mixture through an outer annular orifice of a tube-in-orifice spinneret while simultaneously passing a precipitating solution through the central tube of the spinneret. The emerging hollow fiber travels substantially downward for about 0.01-10 m before submersion into a quenching bath. The asymmetrical, microporous, hollow fiber membrane is biocompatible and suitable for use in, for example, dialysis, hemodialysis, ultrafiltration, and water filtration applications.Type: GrantFiled: May 6, 1993Date of Patent: June 9, 1998Assignee: Minntech CorporationInventors: Randal M. Wenthold, Robert T. Hall, II, Robert G. Andrus, Paul D. Brinda, Louis C. Cosentino, Robert F. Reggin, Daniel T. Pigott
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Patent number: 5723081Abstract: A process for preparing a dispersion spun fluorinated polymer fiber wherein the intermediate fiber structure, immediately before sintering, contains primarily ions characterized as fugitive ions.Type: GrantFiled: December 20, 1996Date of Patent: March 3, 1998Assignee: E. I. du Pont de Nemours and CompanyInventors: Nicole Lee Blankenbeckler, Joseph Michael Donckers, II, Warren Francis Knoff
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Patent number: 5720838Abstract: A doormat is formed by accumulating a large number of monofilaments in a random loop form continuously to present a mottled pattern or a striped pattern by the combination of color monofilaments of two or more colors. This manufacturing device comprises a spinning pack having a rectangular shape for spinning a large number of monofilaments, a plurality of extruders disposed at symmetrical positions in the longitudinal direction of the spinning pack, and a collecting mechanism for collecting the monofilaments spun from the spinning pack. The spinning pack is provided with a resin flowpath unit and a multihole nozzle plate which are superposed, and the resin flowpath unit is connected to the extruders by means of communicating pipe lines disposed at symmetrical positions in the longitudinal direction.Type: GrantFiled: February 29, 1996Date of Patent: February 24, 1998Assignee: Yugengaisya TowaInventor: Akira Nakata
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Patent number: 5714258Abstract: An improved polyester fiber, polymer composition for producing such fibers by spinning and drawing, and a process for improving the production of fibers from polyester is disclosed wherein an aliphatic diester such as ethylene glycol distearate is incorporated into the polyester resin prior to spinning fibers from the resin in trace amounts of from about 0.01 to about 0.4 percent by weight of the polyester. The composition improves the process of spinning and drawing fibers from the resin and produces superior fibers.Type: GrantFiled: December 28, 1995Date of Patent: February 3, 1998Assignee: Hoechest Celanese CorporationInventor: F. Holmes Simons
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Patent number: 5691443Abstract: Aramids which after drawing have high tensile strengths and tensile moduli are made from units derived from selected 2,2'-disubstituted-4,4'-diaminobiphenyls, p-phenylenediamine, oxydianiline and terephthalic acid. Also disclosed is a process for drawing such aramids at least 1.5%, which results in the drawn aramid having significant crystallinity and higher tensile strength. The aramids are useful for ropes and composites.Type: GrantFiled: September 8, 1995Date of Patent: November 25, 1997Assignee: E. I. Du Pont de Nemours and CompanyInventor: Robert Samuel Irwin
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Patent number: 5641450Abstract: A hollow polysulfonic fiber intended for a selectively transmissive membrane contains a hydrophilic polymer which is cross-linked into a water-insoluble form (for example polyvinylpyrrolidone) and is used in the form of a hydrogel containing water. A method for the production of a membrane module consists in spinning a hollow fiber by the use of a spinning solution containing a polysulfonic resin and a hydrophilic polymer, wetting the fiber above the saturated moisture content, and then, with the wet condition maintained, subjecting the fiber to the processes of module molding and radiation induced cross-linking, these processes being performed in either order. The method provides a selectively transmissive hollow polysulfone fiber membrane which displays less elution into water and a sharp molecular weight fractionation, so as to be usable safely in the fields of medicine and foodstuffs.Type: GrantFiled: December 6, 1994Date of Patent: June 24, 1997Assignee: Toray Industries, Inc.Inventors: Takuichi Kobayashi, Kazumi Tanaka
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Patent number: 5639484Abstract: A spinning cell for producing lyocell fibre by spinning a solution of cellulose in an organic solvent through an air gap into a spin bath has nozzles to create a cross-draught through the air gap.Type: GrantFiled: April 3, 1995Date of Patent: June 17, 1997Assignee: Courtaulds Fibres (Holdings) LimitedInventors: Patrick Arthur White, Malcolm John Hayhurst, Alan R. Owens, Ian David Roughsedge, Richard James Davies, Alan Sellars, Jacqueline Faye MacDonald, Michael Colin Quigley, Ralph Draper, Ronald Derek Payne
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Patent number: 5628947Abstract: A process for the simultaneous drying and crystallization of crystallizable thermoplastic synthetic material (plastic), e.g. polyethylene terephthalate, in which plastic from the melt is extruded in cord form, solidified at the surface by quenching in water and crystallized by gas treatment and dried, using a device for cooling and drying the cord emerging from dies having a casting gutter with its acceptance end arranged beneath the dies and a device producing a flow of coolant on the casting gutter within a quenching section, a subsequent dewatering section in which the casting gutter has apertures for the free flow of the coolant, a subsequent drying section in which the casting gutter has closely spaced nozzles for the passage of gas and a granulator downstream of the drying section. The lengths of the quenching, dewatering and drying sections must be such, taking account of the rate of creep of the cord along the casting gutter, that the passage time in the quenching section is a maximum of some 1.Type: GrantFiled: February 15, 1995Date of Patent: May 13, 1997Assignee: Rieter Automatik GmbHInventor: Jurgen Keilert
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Patent number: 5626703Abstract: The present invention relates to a method for preparing a composite material comprising a matrix resin of a thermal plastic resin and a liquid crystal resin which has a liquid crystal transition temperature higher than the minimum temperature of capable of molding said thermal plastic resin and which is formed into a fiber structure as a reinforcing material.The method is characterized in that the composite composition is subjected to a melt extrusion process at an apparent shear rate of 3.times.10.sup.2 to 10.sup.5 sec.sup.-1 and above the liquid crystal transition temperature. The resulting material in a filament or thin film has fibers of the liquid crystal resin having an aspect of more than 3 in the matrix resin, so that it is provided with an improved tensile strength by further being subjected to a drawing process at a drawing ratio of 11 to 120.Type: GrantFiled: January 21, 1993Date of Patent: May 6, 1997Assignee: Mazda Motor CorporationInventors: Takashi Tomita, Masakatsu Ohsugi, Yushi Matsuda, Mitsuharu Kaneko, Keita Sasaki, Kazuhisa Toh, Masayasu Nishihara, Kenji Moriwaki
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Patent number: 5607700Abstract: A synthetic resin pelletizing machine includes an extrusion cylinder forming, with a horizontal plane, an installation angle .theta. which is in the range of 0.degree.<.theta.<90.degree., a raw material feed passage extending upwardly from said extrusion cylinder at a predetermined angle relative to a longitudinal axis of said extrusion cylinder, and a cooling unit disposed below a die head and having a double bath construction composed of a first cooling bath and a second cooling bath disposed in the first cooling bath. The pelletizing machine thus constructed is compact in size and is capable of assuring a smooth feed of a raw material to the extrusion cylinder as well as a smooth passage of an extruded strand through the cooling unit.Type: GrantFiled: April 15, 1994Date of Patent: March 4, 1997Assignee: YKK CorporationInventors: Akiyoshi Kando, Hiroshi Yoshida, Kazuki Kuse
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Patent number: 5601856Abstract: The heat transmission from the heating box of a spinning beam to the nozzle package carried therein in a nozzle throat is improved in such a way that the fixing device for the package is provided with heat receiving elements. These elements are subjected to saturated vapor in operation and are provided with condensation surfaces so as to receive heat from the saturated vapor. The heat received is transmitted to the package via at least one heat bridge.Type: GrantFiled: April 11, 1995Date of Patent: February 11, 1997Assignee: Rieter Automatik GmbHInventors: Willi Kretzschmar, Erik Ortmayer
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Patent number: 5587122Abstract: We have discovered a process for producing a polypropylene suture including the steps of (a) extruding melted polypropylene resin through an orifice and rapidly quenching the melted polypropylene resin to produce a filament; (b) drawing the filament in the range of from about 5.times. to about 7.5.times. to produce a singly drawn filament; (c) drawing the singly drawn filament in the range of form about 1.times. to about 2.5.times. in a second heated zone being maintained at a temperature in the range of from about 30.degree. C. to about 160.degree. C., to form a doubly drawn filament; (d) shrinking the doubly drawn filament in the range of from about 0.75 percent to about 0.95 percent, in a second heated zone being maintained at a temperature in the range of from about 100.degree. C. to about 180.degree. C., to form a polypropylene suture.Type: GrantFiled: February 10, 1995Date of Patent: December 24, 1996Assignee: Ethicon, Inc.Inventor: David J. Lennard
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Patent number: 5534205Abstract: In a process for preparing polybenzoxazole or polybenzothiazole filaments by extruding a polybenzoxazole or polybenzothiazole dope, drawing the dope filament across an air gap, and coagulating the dope filament; the number of filament breaks can be reduced by placing a stress isolation device after extruding but before coagulating the filament.Type: GrantFiled: August 5, 1994Date of Patent: July 9, 1996Assignee: The Dow Chemical CompanyInventors: Timothy L. Faley, Michael E. Mills, Yoshihiko Teramoto, Douglas E. Turek, Kazuyuki Yabuki
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Patent number: 5518670Abstract: The invention relates to a continuous process for the formation of monofilaments having a diameter of from 60 .mu.m to 500 .mu.m from filament-forming polymers by melt-spinning the polymer, optionally quenching the formed polymer filaments below the melt-spinning head with a cooling medium, cooling the filaments in a liquid bath having a temperature of from -10.degree. C. to 150.degree. C., removing the entrained water and post-treating the filaments by spin finishing, drawing and fixing at a filament delivery speed which is greater than 600 to 4000 m/min after the fixing step.Type: GrantFiled: October 13, 1994Date of Patent: May 21, 1996Assignee: Bayer AktiengesellschaftInventors: Jurgen Budenbender, Eckhard Gartner, Jakob Jansen
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Patent number: 5496510Abstract: A process for making acrylic fibers in which control of polymer composition and spin bath composition provide improved product properties.Type: GrantFiled: August 23, 1994Date of Patent: March 5, 1996Inventor: Gary J. Capone
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Patent number: 5476563Abstract: A method for making a door mat comprising an integral mass of loops of synthetic resin monofilaments which includes a surface layer having a decorative pattern on its upper side and a reverse surface layer having its upper side joined to the lower side of said surface layer. The underside of the reverse surface layer may be joined to an anti-slip layer, which may be in the form of a lattice layer.Type: GrantFiled: June 9, 1994Date of Patent: December 19, 1995Assignee: Yugengaisya TowaInventor: Akira Nakata
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Patent number: 5470519Abstract: A method of manufacturing a cellulosic article of cellulose or a cellulose derivative that has incorporated a polyethylene oxide composition having a molecular weight of at least 70,000.Type: GrantFiled: July 26, 1994Date of Patent: November 28, 1995Assignee: Viskase CorporationInventor: John Markulin
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Patent number: 5464491Abstract: A method for producing a mat including a three dimensional filament loop aggregate comprises extruding molten thermoplastic synthetic resin die to form a plurality of filaments. The filaments are heated and descend onto a surface of a cooling liquid, between a pair of rotatable rolls submerged in the cooling liquid. The filaments are all cooled simultaneously by the cooling liquid and form loops on the surface thereof. A first series of loops formed from outermost filaments are supported on one of the rotatable rolls in the cooling liquid, with the loops being horizontal. Rotation of the roll moves these loops into a vertical position. Thereafter, all the loops are integrated, with the loops formed by the outermost filaments being in a vertical position, and the loops formed by the remaining filaments being in the horizontal position.Type: GrantFiled: August 12, 1993Date of Patent: November 7, 1995Assignee: Kabushiki Kaisha RisuronInventor: Minoru Yamanaka
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Patent number: 5451359Abstract: High molecular weight polyester fibers having excellent mechanical strength and useful for various industrial materials, is produced by dry-jet wet spinning a dope solution of a polyester resin comprising repeating ethylene terephthalate units, having an intrinsic viscosity of 1.2 or more and dissolved in a phenolic solvent, through a spinneret, coagulating the resultant filamentary dope solution streams in a bath of coagulating liquid in which the phenolic solvent is soluble and the polyester resin is insoluble, while controlling the temperature of the coagulating liquid to a level of from (Tg-50.degree. C.) to (Tg+45.degree. C.) wherein Tg represents a glass transition temperature of the dope solution, and optionally subjecting the resultant undrawn polyester filaments to a rinsing step with a rinsing liquid, to a drawing step at a total draw ratio of at least 5, and to a heat-treating step.Type: GrantFiled: March 15, 1994Date of Patent: September 19, 1995Assignee: Teijin LimitedInventors: Kazuo Yahata, Ryoji Tsukamoto
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Patent number: 5441394Abstract: A device for cooling and granulating molten thermoplastic strands (1) emerging from dies (2) which either drop along the falling line starting at the dies or are guided in an operating position through a coolant bath (9), freely stressed between guide rollers fitted in the bath and then taken into a granulator (4). In the region between the dies and the coolant bath there is a precooling device (5) which carries the plastic strands emerging from the dies and takes them to the coolant bath. Behind the precooling device there is a gripping device (21 ) with opposed clamping rollers (41, 42) which can open and shut and move along a guiding rail to grip the forward ends of the plastic strands after they have been separated by a separator (22) movable through the falling line of the strands. The rollers with the forward ends of the strands are moved along the guiding rail running through the region of the coolant bath as far as the granulator, where they release the strands thereinto.Type: GrantFiled: April 1, 1994Date of Patent: August 15, 1995Assignee: Rieter Automatik GmbHInventors: Jurgen Keilert, Frank Glockner, Helmut Meidhof, Laurenz Hohm
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Patent number: 5389326Abstract: Aramid and polybenzimidazole fibers and films of improved flame resistance are obtained by impregnation with tungsten hexachloride.Type: GrantFiled: May 23, 1994Date of Patent: February 14, 1995Assignee: E. I. Du Pont de Nemours and CompanyInventors: Robert V. Kasowski, Kiu-Seung Lee
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Patent number: 5374708Abstract: Polyimide filaments and polyimide films having great strength, high elastic modulus and high crystallinity and comprising a novel polyimide which can be melt-processed without impairing high crystallinity and which essentially consists of recurring structural units represented by the formula (I): ##STR1## more than 85 mol % the polyimide consists of recurring structural units of the formula (II): ##STR2## and from 0.5 to 15 mol % of the polyimide consists of recurring structural units represented by the formula (III), the formula (II) exclusive, the formula (IV) and/or the formula (V).Type: GrantFiled: August 8, 1991Date of Patent: December 20, 1994Assignee: Mitsui Toatsu Chemicals, IncorporatedInventors: Shoji Tamai, Masahiro Ohta, Akihiro Yamaguchi, Masumi Saruwatari
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Patent number: 5367046Abstract: A high temperature resistant fiber, especially a polyimide fiber, having a dielectric constant less than 3 is prepared by first reacting 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane with 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride in an aprotic solvent to form a polyamic acid resin solution. The polyamic acid resin solution is then extruded into a coagulation medium to form polyamic acid fibers, which are thermally cured to their polyimide form. Alternatively, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane with 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride to form a polyamic acid, and the polyamic acid is chemically converted to its polyimide form. The polyimide is then dissolved in a solvent to form a polyimide resin solution, and the polyimide resin is extruded into a coagulation medium to form a polyimide wet gel filament. In order to obtain polyimide fibers of increased tensile properties, the polyimide wet gel filaments are stretched at elevated temperatures.Type: GrantFiled: April 10, 1992Date of Patent: November 22, 1994Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: William E. Dorogy, Jr., Anne K. St. Clair
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Patent number: 5362430Abstract: Molten polyamide filaments are extruded from spinneret capillaries through a gas-filled gap and into a quench bath which contains a heated aqueous liquid. The bath has a nozzle defining a vertically disposed cylindrical passageway with its entrance in the bath below the bath surface. The filaments are converged into a filament bundle at the entrance and withdrawn from the exit of the passageway at a withdrawal speed of about 1500 to about 3500 meters per minute. The polyamide polymer is extruded from the spinneret such that the jet velocity in the spinneret capillaries is between 2 and 10% of the withdrawal speed of the filament from the exit of the nozzle passageway.Type: GrantFiled: July 16, 1993Date of Patent: November 8, 1994Assignee: E. I. Du Pont de Nemours and CompanyInventors: John H. Herold, II, Henry Kobsa
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Patent number: 5340479Abstract: A depth filter formed of a plurality of substantially continuous intertwined filaments including a central support zone formed of support filaments having a first diameter and a filter zone formed of filtration filaments having filaments of a second diameter in which the diameters are different or the filaments are constructed of different materials. The invention also relates to an apparatus and a method for making such a depth filter element.Type: GrantFiled: August 20, 1992Date of Patent: August 23, 1994Assignee: Osmonics, Inc.Inventors: Joseph T. Szczepanski, Thomas M. Aune, Henry J. Schneider
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Patent number: 5296286Abstract: A process for preparing subdenier fibers and structures thereof from isotropic polymer solutions is disclosed. The process comprises extruding a stream of the polymer solution into a chamber, introducing a pressurized gas into the chamber, directing the gas in the flow direction of and in surrounding contact with the stream within the chamber, passing both the gas and the stream into a zone of lower pressure at a velocity sufficient to attenuate the stream and fragment it into fibers, and contacting the fragmented stream in the zone with a coagulating fluid.Type: GrantFiled: January 11, 1993Date of Patent: March 22, 1994Assignee: E. I. Du Pont de Nemours and CompanyInventors: Steven R. Allen, David M. Gale, Aziz A. Mian, Sam L. Samuels, Hsiang Shih
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Patent number: 5294395Abstract: Thermoplastic monofilament sutures having improved flexibility and handling characteristics are obtained by a melt spinning process which includes the step of drawing the filaments in a heated zone maintained at a temperature above the melting temperature of the filament. The resulting monofilament sutures have a higher elongation and lower modulus than comparable monofilament sutures obtained without the heated drawing step, and are characterized by a crystalline structure which is more highly ordered in the core of the monofilament suture than in a surrounding annular area.Type: GrantFiled: May 12, 1993Date of Patent: March 15, 1994Assignee: Ethicon, Inc.Inventor: Ephraim Broyer
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Patent number: 5286833Abstract: A process for making PBZ fibers of ultra-high physical properties is given. Polybenzoxazole fibers made by the process of this invention have tensile strengths nearly double in value from what has been reported previously.Type: GrantFiled: December 3, 1992Date of Patent: February 15, 1994Assignee: The Dow Chemical CompanyInventors: Robert A. Bubeck, Stephen J. Nolan, Chieh-Chun Chau, Steven Rosenberg, Mark D. Newsham, Myrna Serrano
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Patent number: 5286435Abstract: Fibers of linear polyethylene or polypropylene are solution spun, cooled, dried in hot air and hot drawn. Drying and hot drawing are carried out by passing a moving filament of the wet polymer through a hot air dryer having an air temperature of at least 55.degree. C., preferably at least 60.degree. C., then heating and hot drawing a moving filament of the dried fiber. Optional steps include wet drawing the fiber prior to drying, and solvent exchange of the original solvent, e.g. decalin, for a more volatile solvent.Type: GrantFiled: December 31, 1987Date of Patent: February 15, 1994Assignee: Bridgestone/Firestone, Inc.Inventors: Leonid I. Slutsker, Kenneth R. Lucas, Georg G. A. Bohm
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Patent number: 5279783Abstract: A process for manufacturing polyamide monofilament suture includes the steps of extruding a polyamide resin, stretching the solidified monofilament and annealing the stretched monofilament so that it shrinks to within about 80 to about 97 percent of the length of the monofilament prior to annealing. The polyamide monofilament sutures so produced exhibit reduced energy compared to conventional polyamide monofilament sutures.Type: GrantFiled: January 30, 1992Date of Patent: January 18, 1994Assignee: United States Surgical CorporationInventors: Cheng-Kung Liu, John C. Brewer
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Patent number: 5268133Abstract: Ultra-oriented, crystalline synthetic filaments with high tenacity are produced by extrusion of a fiber-forming synthetic polymer melt into a liquid isothermal bath maintained at a temperature of at least 30.degree. C. above the glass transition temperature of the polymer, withdrawing the filaments from the bath and then winding up the filaments. Polyethylene terephthalate filaments so produced at 3000-5000 m/min exhibit a crystalline structure and possess birefringence of 0.20-0.22, tenacity of 7-9 g/d, break elongation of 14-30% and boil-off shrinkage of 5-10%.Type: GrantFiled: February 4, 1992Date of Patent: December 7, 1993Assignee: North Carolina State UniversityInventors: John A. Cuculo, Paul A. Tucker, Gao-Yuan Chen, Ferdinand Lundberg
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Patent number: 5264173Abstract: A process for producing a high strength and high initial modulus polyvinyl alcohol monofilament yarn. The monofilament yarn is polyvinyl alcohol having a polymerization degree of from 1500 to 7000, a tensile strength of not less than 10 g/d and an initial modulus of not less than 200 g/d, with a fineness of 100 denier or more. The monofilament yarn is made by dry-wet spinning a spinning dope prepared by dissolving polyvinyl alcohol having a polymerization degree of from 1500 to 7000 in a solvent and stretching the resulting unstretched filament, where a plurality of filaments immediately after being spun from a spinning nozzle having a plurality of orifices are closely adhered and united into a substantially single strand in an inert atmosphere and then introduced into a coagulating bath or a cooling bath.Type: GrantFiled: August 22, 1991Date of Patent: November 23, 1993Inventors: Masatsugu Mochizuki, Kazutaka Kooda, Siro Murakami, Naohiko Nagata, Mitsuo Kawaguchi
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Patent number: 5262099Abstract: A process of the type including the steps of spinning, water-quenching, and drawing a heavy denier, polyamide monofilament in at least first and second draw stages to a total draw ratio of at least about 5.5.times.. The quenched monofilament is advanced in the first draw stage through a steamer containing a high temperature steam atmosphere and is advanced in the second draw stage through a zone heated with a radiant heater. The improvement includes:advancing the monofilament through a draw point localization zone in the first draw stage in advance of and remote from the steamer;providing a generally uniform coating of liquid water to the monofilament in the draw point localization zone, the water being provided in an amount greater than about 5% by weight based on the dry weight of the monofilament; andheating the coating of water on the monofilament in the draw point localization zone generally uniformly to a temperature greater than about 90.degree. C.Type: GrantFiled: April 1, 1992Date of Patent: November 16, 1993Assignee: E. I. Du Pont de Nemours and CompanyInventors: Earl B. Adams, Robert K. Anderson, Rajive K. Diwan
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Patent number: 5238982Abstract: Disclosed is a method for producing polyamide fibers with reduced flammability by melt mixing a polyamide with a phosphate ester of the general formula: ##STR1## wherein n is a number of from 1 to 10;m is a number of from 0 to 3;x is a number of from 0 to 3;R is linear or branched C.sub.1 - to C.sub.18 - alkyl radical;at a temperature of from about 180.degree. to about 280.degree. C., and melt spinning fibers.Type: GrantFiled: September 24, 1992Date of Patent: August 24, 1993Assignee: BASF CorporationInventors: Atish Adhya, Robert L. Lilly
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Patent number: 5223187Abstract: Polyester of high intrinsic viscosity is spun, steam-heated, drawn and wound up in a multi-stage continuous process to provide an improved monofilament that is particularly suited for reinforcing rubber, e.g. in tires, after suitable dip-coating, stretching and setting.Type: GrantFiled: June 26, 1991Date of Patent: June 29, 1993Assignee: E. I. Du Pont de Nemours and CompanyInventors: William A. Chantry, Amy G. Roberson, Taracad K. Venkatachalam