Filaments Patents (Class 264/178F)
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Patent number: 5185116Abstract: Extruded shaped structures of amorphous polyarylate copolymers, having a tensile elongation at break of at least 80% at 25.degree. C., are made by drawing a molten extrudate of the copolymer at a temperature at least 100.degree. C. above the glass transition temperature of the copolymer.Type: GrantFiled: June 14, 1991Date of Patent: February 9, 1993Assignee: E. I. Du Pont de Nemours and CompanyInventor: Charles W. Stewart
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Patent number: 5183611Abstract: A method of producing a polymer article having a metallized surface, which comprises dissolving a polymer and a metal salt in a common solvent, forming a polymer article containing the metal salt dispersed therein from the solution, and then treating the article with a reducing agent.Type: GrantFiled: November 30, 1988Date of Patent: February 2, 1993Assignee: Nisshinbo Industries, Inc.Inventors: Ryutoku Yosomiya, Mistutoshi Hirata, Kiyotaka Morimoto, Soichiro Takenishi, Toshinori Marutsuka
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Patent number: 5181940Abstract: A process for producing highly asymmetric hollow fibers useful as permselective gas separation membranes and for producing composite membranes thereof by extruding the spinning dope through a tube-in-orifice spinneret into a gas-filled chamber maintained at reduced pressure and then conveying the extruded hollow fiber through a liquid bath to solidify the extrudate.Type: GrantFiled: August 1, 1991Date of Patent: January 26, 1993Assignee: Union Carbide Industrial Gases Technology CorporationInventors: Benjamin Bikson, James T. Macheras, Joyce K. Nelson
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Patent number: 5171504Abstract: The invention provides improved thermoplastic high strength, highly oriented fibers and a process for producing the fibers by melt spinning a thermoplastic polymer to form a threadline, preferably passing the threadline through a thermal conditioning zone and then quenching the threadline. The quenched threadline is passed through a hydraulic drag bath maintained at a temperature of greater than the glass transition temperature of the polymer which substantially increases the threadline stress and results in drawing of the threadline. The threadline is withdrawn from the drag bath at a withdrawal rate of at least 3,000 meters per minute.Type: GrantFiled: March 28, 1991Date of Patent: December 15, 1992Assignee: North Carolina State UniversityInventors: John A. Cuculo, Paul A. Tucker, Chon-Yie Lin, Ferdinand Lundberg
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Patent number: 5149480Abstract: 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: May 18, 1990Date of Patent: September 22, 1992Assignee: North Carolina State UniversityInventors: John A. Cuculo, Paul A. Tucker, Gao-Yuan Chen, Ferdinand Lundberg
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Patent number: 5124428Abstract: Fiber grade resin, fiber obtained therefrom, and fiber-containing articles wherein the resin comprises an amide-imide polymer having repeating units of the following general formula: ##STR1## said resin having an inherent viscosity of from about 0.3 to about 1.3 dl/g; an M.sub.n of at least about 5000 g/mole; a ratio of M.sub.w /M.sub.n in the range of from about 1.7 to about 3.3; and a ratio of M.sub.z /M.sub.w of not greater than about 2.Type: GrantFiled: May 31, 1991Date of Patent: June 23, 1992Assignee: Amoco CorporationInventors: Howard B. Yokelson, Stefanos L. Sakellarides, Raymond T. Behrends, Marifaith Hackett
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Patent number: 5095075Abstract: Provided is a molecular composite comprising a rigid-rod aromatic heterocyclic polymer, a flexible, coil-like thermoplastic polymer and a thermosetting polymer.Also provided is a method for fabricating a molecular composite film or fiber which comprises the steps of forming a biphasic, stir opalescent solution of a rigid-rod aromatic heterocyclic polymer, a thermoplastic polymer, a thermosetting polymer and a solvent which is common to the three polymers, adding solvent to the solution until the solution becomes isotropic and stir opalescence has ceased to determine the critical concentration of polymers in the solvent, adding additional solvent to the solution so that the polymer concentration is below the critical concentration, extruding the solution into a non-solvent for the polymers to form the desired film or fiber, drying the film or fiber and hot drawing the film or fiber at a temperature above the Tg of the thermoplastic, but below the polymerization temperature (Tpoly) of the thermosetting resin.Type: GrantFiled: December 11, 1990Date of Patent: March 10, 1992Assignee: The United States of America as represented by the Secretary of the Air ForceInventors: Fred E. Arnold, Thaddeus E. Helminiak, Donald R. Wiff, Loon S. Tan, Wen F. Hwang, Hoe Chuah
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Patent number: 5082610Abstract: An improved process comprising treating monofilaments with high temperatures to deorient the surface. A preferred product is a heavy denier transparent polyamide monofilament, especially suitable as fishing line.Type: GrantFiled: October 23, 1989Date of Patent: January 21, 1992Assignee: E. I. Du Pont de Nemours and CompanyInventors: Robert B. Fish, Jr., Robert L. Rackley, Robert K. Anderson, Michael H. Mainz
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Patent number: 5082611Abstract: A process for making oriented thermoplastic monofilaments having a tenacity greater than about 7.5 g/d at a standard deviation in tenacity of less than 0.25.Type: GrantFiled: December 22, 1988Date of Patent: January 21, 1992Assignee: E. I. du Pont de Nemours and CompanyInventors: Earl B. Adams, Robert K. Anderson, Rajive K. Diwan
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Patent number: 5078925Abstract: Polypropylene articles are provided. The polypropylene articles include non-crystalline mesomorphous polypropylene having olefinic unsaturation-containing monomers graft-polymerized thereon by ionizing radiation in a dosage sufficient to degrade crystalline polypropylene. The irradiated polypropylene articles retain useful tensile properties after storage periods of as long as at least about four months.Type: GrantFiled: June 27, 1990Date of Patent: January 7, 1992Assignee: Minnesota Mining and Manufacturing CompanyInventors: Richard J. Rolando, Dennis L. Krueger, Daniel E. Meyer, Thomas L. Insley
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Patent number: 5066210Abstract: Apparatus for cooling and granulating extrusions of thermoplastic issuing from extrusion dies is provided with a pair of mirror image symmetric channels formed of guide plates arranged back to back. The upper ends of the channels are exposed to a cooling medium and the lower ends are directed to the entrance of a granulator having draw-in rollers. The guide plates are laterally separable from one another to provide increased tension in the extrusion being fed to the granulator.Type: GrantFiled: April 26, 1989Date of Patent: November 19, 1991Assignee: Automatik Apparate-Maschinenbau GmbHInventor: Friedrich Hunke
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Patent number: 5026819Abstract: The reactivity of aromatic copolyamide fiber and film is enhanced by incorporation of small amounts of 4,4'-diaminodiphenic acid units in the polymer chain.Type: GrantFiled: December 5, 1989Date of Patent: June 25, 1991Assignee: E. I. Du Pont de Nemours and CompanyInventor: Robert S. Irwin
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Patent number: 5019316Abstract: A system for producing a drawn yarn having a durable mechanical and thermal stability in practical use from a fiber-forming polymer by means of a single continuous process is disclosed. A yarn extruded from a spinneret is first introduced into a liquid bath for cooling and subsequently to a hot chamber filled with a pressurized steam for heat-treatment, in which the yarn is drawn against a resistance caused by the liquid bath. The vessel of the liquid bath is provided with a yarn exit path adapted to allow the passage of the yarn but inhibit the leakage of the liquid and to remove a concomitant liquid from the yarn. The hot chamber is provided with inlet and outlet paths for the yarn also adapted to allow the passage of the yarn but inhibit the leakage of the steam. The system is suitable for producing for industrial use a yarn composed of thicker individual filaments.Type: GrantFiled: July 24, 1989Date of Patent: May 28, 1991Assignee: Toray Industries, Inc.Inventors: Kunihiko Ueda, Katsumi Hasegawa, Nobuyuki Kuriyama
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Patent number: 4977223Abstract: Provided is a molecular composite comprising a rigid-rod aromatic heterocyclic polymer, a flexible, coil-like thermoplastic polymer and a thermosetting polymer.Also provided is a method for fabricating a molecular composite film or fiber which comprises the steps of forming a biphasic, stir opalescent solution of a rigid-rod aromatic heterocyclic polymer, a thermoplastic polymer, a thermosetting polymer and a solvent which is common to the three polymers, adding solvent to the solution until the solution becomes isotropic and stir opalescence has ceased to determine the critical concentration of polymers in the solvent, adding additional solvent to the solution so that the polymer concentration is below the critical concentration, extruding the solution into a non-solvent for the polymers to form the desired film or fiber, drying the film or fiber and hot drawing the film or fiber at a temperature above the Tg of the thermoplastic, but below the polymerization temperature (Tpoly) of the thermosetting resin.Type: GrantFiled: February 2, 1989Date of Patent: December 11, 1990Assignee: The United State of America as represented by the Secretary of the Air ForceInventors: Fred E. Arnold, Thaddeus E. Helminiak, Donald R. Wiff, Loon S. Tan, Wen F. Hwang, Hoe Chuah
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Patent number: 4970042Abstract: A synthetic fiber having an uneven surface structure consisting of wrinkles having ridges and recesses of the surface of the fiber and not presenting specular luster, which may be used, for example, as artificial hair for wigs, can be produced easily and stably by melt-spinning a starting synthetic resin such as nylon and passing the spun monofilament through a cooling bath at a temperature not lower than 30.degree. C. for a period of time sufficient for developing wrinkles in its surface. Inclusion of a pigment such as carbon black in an appropriate amount in the starting material is effective in providing dense distribution of wrinkles.Type: GrantFiled: August 8, 1989Date of Patent: November 13, 1990Assignee: Aderans Co., Ltd.Inventors: Hiroshi Kakiuchi, Setsuo Fukuhara, Michinobu Fujiwara, Hiroshi Maeda, Yutaka Shirakashi, Osamu Asakura, Yoshihiro Yoneda, Tetsuo Noda, Naoyuki Fujita
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Patent number: 4968470Abstract: Asymmetric polyacetylene polymer membranes having both improved selectivity and improved flux are provided by a process which comprises forming a solution containing from about 1 to about 5% by weight of a polyacetylene polymer in any suitable solvent therefor, forming the solution into a thin film and quenching the film in an aqueous bath in the presence of from about 0.002 to about 0.4% by weight of the quench bath of surfactant with an HLB value of 11 to 15. Additionally, the polyacetylene polymer solution contains a swelling agent at about 1% to about 10% by weight of polyacetylene polymer solution.Type: GrantFiled: November 15, 1989Date of Patent: November 6, 1990Assignee: Air Products and Chemicals, Inc.Inventors: Stephen C. Lynch, James K. Smith, John W. McTopy, II, Pushpinder S. Puri
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Patent number: 4963298Abstract: Process for preparing subdenier fiber and structures thereof from lyotropic liquid crystalline polymers comprising extruding a stream of the polymer 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 zoner 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: February 1, 1989Date of Patent: October 16, 1990Assignee: E. I. Du Pont de Nemours and CompanyInventors: Steven R. Allen, Aziz A. Mian, Sam L. Samuels
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Patent number: 4952265Abstract: In this mat consisting of filament loop aggregations, irregular form loops are formed in the upright direction by respectively winding to be coil-like many filaments coarse in the arranging intervals and made of a thermoplastic synthetic resin and are fused in the intersecting parts and the other loops are formed in the laterally fallen direction and are fused in the overlapping parts.Type: GrantFiled: April 12, 1988Date of Patent: August 28, 1990Assignee: Kabushiki Kaisha RisuronInventors: Minoru Yamanaka, Tetsuo Amawa
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Patent number: 4944775Abstract: A process for producing integrally-skinned asymmetric poly(phenylene oxide) gas separation membranes is disclosed. The process involves forming a solution of the poly(phenylene oxide) in an aprotic solvent at an elevated temperature, forming a nascent membrane from the solution, partially drying the nascent membrane, followed by coagulating the partially dried nascent membrane in a coagulation bath formed from a non-solvent for the poly(phenylene oxide) which non-solvent is miscible with the aprotic solvent.Type: GrantFiled: July 11, 1989Date of Patent: July 31, 1990Assignee: E. I. du Pont de Nemours and CompanyInventor: Richard A. Hayes
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Patent number: 4923662Abstract: A process for producing polyester fibers having excellent tensile properties, particularly suitable as reinforcement material for tires, belts, etc., involves melt-spinning an ethylene terephthalate polyester to form highly oriented low crystalline polyester filaments which, at the state of being taken-up and prior to being drawn, having birefringence (.DELTA.n) and specific gravity (SG) within the below indicated ranges (a) and (b), and then, without winding-up, subjecting the said filaments immediately to drawing and heat treatment between the first godet rolls and second godet rolls under a draw ratio (DR) defined by the following formulas:.DELTA.n.gtoreq.5SG-6.64 (a).DELTA.n.gtoreq.0.100 (b)2.0.gtoreq.DR>1.Type: GrantFiled: December 21, 1988Date of Patent: May 8, 1990Assignee: Toyo Boseki Kabushiki KaishaInventors: Kazuo Kurita, Yoshihiko Teramoto
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Patent number: 4921668Abstract: An improved process comprising flame treating monofilaments from which a preferred product is a heavy denier transparent polyamide monofilament, especially suitable as fishing line.Type: GrantFiled: October 13, 1987Date of Patent: May 1, 1990Assignee: E. I. du Pont de Nemours and CompanyInventors: Robert K. Anderson, Michael H. Mainz, Robert L. Rackley
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Patent number: 4913757Abstract: A method of producing a mat consisting of filament loop aggregations. The first step is that of forming a first filament loop aggregation low in the filament density wherein many filaments are made. These by extruding a thermoplastic synthetic resin out of a T-die and arranging the resin longitudinally and laterally at intervals for continuous molding. The resin is deposited on a boiling water surface. The filament temperature is maintained close to the temperature at the time of molding by heating while the filament bundle is vertically lowered toward a cooling water surface and is sunk into water in the vertical direction.Type: GrantFiled: April 12, 1988Date of Patent: April 3, 1990Assignee: Kabushiki-Kaisha RisuronInventors: Minoru Yamanaka, Tesuo Amawa
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Patent number: 4886631Abstract: A hollow fiber membrane made of a cellulose ester having a membrane thickness of not more than 75 .mu.m, and having void volume (x, % by volume) of the membrane and a rate of ultrafiltration (y, ml/m.sup.2.hr.mmHg) satisfying the following formula:55x-2500.ltoreq.y.ltoreq.48x+600wherein x.gtoreq.60,and further has a .beta.-lipoprotein sieving coefficient (sc) of not less than 0.95, and preferably having further not more than 2% of change ratio in the axial direction and in the radial direction when dipped freely in water at 121.degree. C. for 20 minutes. Said hollow fiber membrane is useful for the medical use, such as the exchange of plasma in patients, collection of plasma from healthy donors, the pre-treatment of plasma for the collection and purification of valuable materials contained in plasma.Type: GrantFiled: September 2, 1988Date of Patent: December 12, 1989Assignee: Toyo Boseki Kabushiki KaishaInventors: Mitsuru Suzuki, Makoto Ohno, Isamu Yamamoto
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Patent number: 4883628Abstract: Polyacrylonitrile (PAN) fibers are prepared by forming a 2-15 weight % solution of PAN of M.sub.w at least 500,000, extruding, cooling to below the gel temperature, extracting and drying. At least one of the gel fiber, the fiber containing extraction solvent and the dried gel is stretched. The product PAN fibers have a M.sub.w at least 500,000 (e.g. 1,000,000-4,000,000 or 1,500,000-2,500,000), a tenacity at least 5 g/den (e.g., at least 7 g/den) and a secant modulus at least 100 g/den (e.g. at least 125 g/den).Type: GrantFiled: September 18, 1986Date of Patent: November 28, 1989Assignee: Allied-Signal Inc.Inventors: Young D. Kwon, Sheldon Kavesh, Dusan C. Prevorsek
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Patent number: 4883496Abstract: A process for dyeing crystalline poly(meta-phenylene isophthalamide) fibers with a water-insoluble dye padded onto such fibers by heating with steam at critical temperatures first to activate the dye and thereafter to diffuse it into the fibers.Type: GrantFiled: December 30, 1988Date of Patent: November 28, 1989Assignee: E. I. Du Pont de Nemours and CompanyInventor: Hamid M. Ghorashi
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Patent number: 4882106Abstract: A material is formed into hollow fiber form, and the surface characteristics of the interior bore is selectively modified in a predetermined fashion by a reactive lumen fluid. Nucleophilic materials, such as regenerated cellulose, can be formed into hollow fibers and simultaneously modified to improve their biocompatibility in accordance with the invention.Type: GrantFiled: March 11, 1987Date of Patent: November 21, 1989Assignee: Baxter Travenol Laboratories, Inc.Inventors: Richard J. Johnson, Dennis E. Chenoweth, Daniel R. Boggs, Michael J. Lysaght
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Patent number: 4863662Abstract: A thermoplastic polymer yarn is spun into a spinning tube charged with a pressurized gas of more than 1 kg/cm.sup.2 G and withdrawn through a yarn exit provided with a unique sealing means which substantially prevents the charged gas from leakage but allows passage of the yarn out from the spinning tube. The resultant yarn has a high molecular orientation due to the improved quenching effect and the increase of resistance against yarn travelling of the charged gas.Type: GrantFiled: July 29, 1988Date of Patent: September 5, 1989Assignee: Toray IndustriesInventors: Katsumi Hasegawa, Michio Ohno, Isoo Saito, Kotaro Fujioka
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Patent number: 4859516Abstract: In this mat consisting of filament loop aggregations, the filament loop aggregations wherein irregular form loops are formed in the upright direction by respectively winding to be coil-like many filaments coarse in the arranging intervals and made of a thermoplastic synthetic resin and are fused in the intersecting parts are overlapped above and below an intermediate filament loop aggregation layer high in the filament density and formed of coiled loops in the partly or all laterally fallen direction.Type: GrantFiled: April 12, 1988Date of Patent: August 22, 1989Assignee: Kabushiki Kaisha RisuronInventors: Minoru Yamanaka, Tetsuo Amawa
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Patent number: 4859390Abstract: A process for the production of polyamide mouldings, characterized in that a polyamide melt is extruded through nozzles to form strands, which at a temperature of from 25.degree. C. below to the respective polyamide softing point in a ratio of from 1:1.5 to 1:8 are stretched and granulated, and the granulate is worked-up in a known manner to produce injection mouldings.Type: GrantFiled: November 4, 1987Date of Patent: August 22, 1989Assignee: Bayer AktiengesellschaftInventors: Karl H. Fritsch, Peter Bier
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Patent number: 4842915Abstract: A spunbonded fabric is described that is made of polyester matrix filaments and a binding component consisting of thermoplastically softenable fibers, filaments or the like, and that is suitable for use as a tufting base. The melting point of the polyester matrix filaments is by at least 90.degree. C. above that of the binding component. In the tufted condition, before the coating of the back, the maximum tensile stretching value of the carpet material is more than 50%.Type: GrantFiled: December 8, 1987Date of Patent: June 27, 1989Inventors: Ludwig Hartmann, Engelbert Loecher, Ivo Ruzek, Norbert Weber
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Patent number: 4826599Abstract: A method for producing a composite hollow fiber membrane by coating a porous hollow fiber substrate with a dilute solution of a membrane-forming composition containing a membrane-forming material and a solvent therefor by contacting the porous hollow fiber substrate with the composition, partially evaporating some of the solvent from the coated porous hollow fiber substrate, contacting the partially dried coating porous hollow fiber substrate with a coagulant and recovering the composite hollow fiber membrane. Also included are the composite hollow fiber membranes so produced and their use as permeable membranes for separating at least one fluid from at least one other fluid in a fluid mixture.Type: GrantFiled: July 10, 1987Date of Patent: May 2, 1989Assignee: Union Carbide CorporationInventors: Benjamin Bikson, Joyce K. Nelson
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Patent number: 4822546Abstract: High melt flow rate polymers are pelletized with greater uniformity and less malformed pellets from underwater extrusion process by die orifices having a narrow preland sufficient to evenly distribute the polymer followed by a wide final hole that forms a polymer strand sufficient to avoid deformation by water currents during pelletization.Type: GrantFiled: August 6, 1987Date of Patent: April 18, 1989Assignee: Exxon Chemical Patents Inc.Inventor: Dwight T. Lohkamp
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Patent number: 4816550Abstract: Improved feed yarns for air-jet texturing are provided by using high molecular weight polyamide polymer spun through non-round capillaries at high spinning speeds to give filament modification ratios greater than 1.5.Type: GrantFiled: January 11, 1988Date of Patent: March 28, 1989Assignee: Monsanto CompanyInventors: Frank Stutz, Jing-peir Yu, Stanley E. McKinney
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Patent number: 4783289Abstract: Extruded articles such as filaments and films are fabricated by blending the components of a curable liquid silicone rubber composition at temperatures of from -60.degree. to +5.degree. C. and then extruding the composition into water maintained at a temperature of at least +25.degree. C. to cure said composition. The water bath preferably contains a surfactant to facilitate processing of the extruded article. The present method provides uniformly cured articles that are almost bubble-free and have low shrinkage ratios.Type: GrantFiled: March 24, 1987Date of Patent: November 8, 1988Assignee: Toray Silicone Co., Ltd.Inventors: Koji Shimizu, Mitsuo Hamada
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Patent number: 4758649Abstract: Heat resistant organic fibers comprising a wholly aromatic polymer having amide group and/or imide group, said fibers having properties satisfying the following formulasTm.gtoreq.350.degree. C.,Tm-Tex.gtoreq.30.degree. C.Xc.gtoreq.10%DE.gtoreq.10%DSR(Tm).ltoreq.15%, and ##EQU1## wherein Tm is a melting point; Tex is an exotherm starting temperature; Xc is a degree or crystallization; DE is an elongation; DSR is a dry shrinkage factor at Tm; and DSR(Tm+55.degree. C.) is a dry shrinkage factor at Tm+55.degree. C. The process for producing the fibers is also disclosed.Type: GrantFiled: May 13, 1987Date of Patent: July 19, 1988Assignees: Kuraray Co., Ltd., Mitsui Toatsu Chemicals, Inc.Inventors: Shoji Asano, Akio Ohmory, Akitsugu Akiyama, Masanori Osawa, Kohei Shizuka, Masahiro Kouno
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Patent number: 4753762Abstract: A method of forming foamed fibers which comprises the steps of forming a melt of a polymer of fiber-forming molecular weight in which is admixed a blowing agent, and a closed-cell-forming additive, extruding said melt through a spinnerette, quenching said melt downstream of said spinnerette under conditions at which bubbles form in said melt, and drawing said melt as it is quenched to produce a foamed fiber having fine bubbles contained therein is disclosed. The product fibers may contain substantially only closed-cells and/or substantially uniform cross sectional area cells.Type: GrantFiled: July 8, 1985Date of Patent: June 28, 1988Assignee: Allied CorporationInventors: Hsin L. Li, Theodore Largman, Frank Mares, Hendrikus J. Oswald
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Patent number: 4739025Abstract: A product and method for obtaining a radiation-resistant polyolefin-containing product, by handling and processing the corresponding homopolymer or copolymer melt and resulting extrudate in a manner favoring retention of a high smectic and less than about 20 wt % monoclinic configuration.Type: GrantFiled: May 5, 1986Date of Patent: April 19, 1988Assignee: Hercules IncorporatedInventor: George N. B. Burch
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Patent number: 4728346Abstract: Asymmetric gas separation membranes having graded density skins and macrovoid-free morphology comprised of glassy, hydrophobic polymers which when contacted on the graded density skin surface with an effective amount of permeation modifier and a coating in occluding contact, exhibit permeation selectivities greater than the intrinsic permeation selectivities for at least one gas of a gaseous mixture than a bulk sample of the polymers. The permeation modified membranes have increased free volume as evidenced by the membrane first heat T.sub.g which is greater than the T.sub.g of the bulk sample of the glassy, hydrophobic polymers; however the permeation modified membranes having an effective amount of permeation modifier added in non-uniform mode are achieved without significant loss in the physical properties of the membrane, including T.sub.g.Type: GrantFiled: August 15, 1986Date of Patent: March 1, 1988Assignee: Permea Inc.Inventor: Milton K. Murphy
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Patent number: 4702876Abstract: Fibers are air-gap spun from a polymeric spinning mass comprising an aromatic polyamide (such as poly-p-phenyleneterephthalamide) by extrusion through a spinneret, passing through an air-gap, passage through a liquid (such as water), and exiting the liquid via an aperture which is variable in size. The use of such an aperture allows easier use of the equipment (especially the stringing up operation) and better fibre properties (such as tensile strength).Type: GrantFiled: July 11, 1985Date of Patent: October 27, 1987Assignee: Akzo N.V.Inventors: Johan L. Ebregt, Hendrik Maatman
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Patent number: 4668448Abstract: The processing by shaping, in particular includes here the moulding, spinning, extrusion, compression and injection moulding of polymers. An electric field thereby influences the flowing polymer melt before and/or during and/or after shaping. The temperature of the melt is maintained at a value between the glass temperature and the isotropic point. Thermotropic liquid-crystalline polymers are used as starting product. Among these are, in principle, all polymers which have mesogenic groups in the main and/or side chain and which can be processed from the liquid-crystalline melt phase. The orientation distribution and thus also the mechanical properties of the end product can be purposefully regulated by the electric field.Type: GrantFiled: July 30, 1985Date of Patent: May 26, 1987Assignee: Bayer AktiengesellschaftInventors: Gunter Weber, Hans-Rudolf Dicke, Roland Vogelsgesang, Walter Simm, Hermann Brinkmeyer
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Patent number: 4663101Abstract: Solutions of intermediate molecular weight polymers from about 200,000 to about 4,000,000, such as polyethylene, in a relatively non-volatile solvent are extruded through an aperture at constant concentration and thereafter stretched at a ratio of at least about 3:1 prior to cooling to form a first gel. The first gels are extracted with a volatile solvent to form a second gel, and the second gel is dried to form a low porosity xerogel. Stretching occurs with any one or more of the first gel, second gel or xerogel. The polyethylene products produced by our process include products having a molecular weight between about 200,000 and about 4,000,000 a tenacity of at least about 13 grams/denier, a modulus of at least about 350 gram/denier, a porosity of less than 10% by volume, a crystalline orientation function of at least about 0.95, and a main melting temperature of at least about 140.degree. C.Type: GrantFiled: January 11, 1985Date of Patent: May 5, 1987Assignee: Allied CorporationInventors: Sheldon Kavesh, Dusan C. Prevorsek
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Patent number: 4642211Abstract: Dry polycaprolactam granules containing from 8 to 13% by weight of caprolactam and its oligomers are prepared by a method in which a caprolactam melt is extruded, the extrudates are cooled to 100.degree.-150.degree. C., left at this temperature until the polycaprolactam has substantially crystallized, and then immediately granulated, and the granules are left in a stream of inert gas, in the absence of molecular oxygen, for from 1 to 4 hours at from 100.degree. to 150.degree. C., and are then cooled.Type: GrantFiled: October 19, 1984Date of Patent: February 10, 1987Assignee: BASF AktiengesellschaftInventors: Peter Elbs, Wolfgang-Dieter Jeserich, Rudolf Wehr
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Patent number: 4621638Abstract: A surgical suture made of a polymer filament having the "hard" elastic properties of reversible elasticity and retention of diameter on stretching.Type: GrantFiled: July 15, 1985Date of Patent: November 11, 1986Assignee: Pfizer Hospital Products Group, Inc.Inventor: Thomas A. Silvestrini
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Patent number: 4615846Abstract: A method of manufacturing an amalgam for sealing in a fluorescent lamp consisting of tin, lead, bismuth, indium and mercury is disclosed. In this method, the amalgam is first melted and then discharged through a nozzle to be contacted with a coolant. A fluorescent lamp containing the amalgam manufactured by the above method is also disclosed.Type: GrantFiled: September 18, 1984Date of Patent: October 7, 1986Assignee: Kabushiki Kaisha ToshibaInventors: Hisashi Yoshino, Masakatsu Haga, Takashi Yorifuji, Teruo Oshima
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Patent number: 4612119Abstract: A polysulfone hollow fiber filter medium having substantially no skin layer in the outer and inner surface areas, the maximum diameter of the pores being from 0.1 to 5 .mu.m., the maximum diameter of the openings of the pores formed in the inner surface being from 0.01 to 10 .mu.m. and the maximum diameter of the openings of the pores formed in the outer surface being from 0.01 to 5 .mu.m., which is prepared by extruding a solvent solution of a polysulfone from a ring nozzle together with an inside coagulating liquid extruded from the inside of the ring nozzle, said solution having a transition temperature at which the viscosity rise changes to the viscosity drop when the temperature of the solution is dropped, and being maintained at a temperature of not less than the transition temperature, and immediately or after passing through a dry space of not more than 50 cm.Type: GrantFiled: April 9, 1984Date of Patent: September 16, 1986Assignee: Kanegafuchi Kagaku Kogyo Kabushiki KaishaInventor: Tamiyuki Eguchi
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Patent number: 4564488Abstract: The invention concerns porous fibers and membranes, methods for their preparation and for their use. The fibers are characterized by a smooth porous surface and an apparent density of between about 10 and 90% of the true density of the polymeric starting material employed. The process involves the formation of a homogeneous mixture of at least two components, one of which is a meltable polymer and another liquid inert with respect to the polymer. The mixture formed must be of a binary type, in which there is a temperature range of complete miscibility and a range in which there is a miscibility gap. The mixture is extruded at a temperature above the separation temperature into a bath containing at least some of the inert liquid which is at a temperature below the separation temperature. Upon introduction of the mixture into the bath, the fiber structure of the product is fixed.Type: GrantFiled: January 10, 1983Date of Patent: January 14, 1986Assignee: Akzo NVInventors: Klaus Gerlach, Erich Kessler
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Patent number: 4557955Abstract: The invention relates to films and tubular structures which are selectively permeable to liquids and gases which are based on a copolymer composed of a copolymerized fluorinated olefin, copolymerized vinyl acetate and, optionally, a copolymerized olefin. It is possible for the acetate groups of the copolymer to have been saponified to form OH groups. The films or tubular structures have in each case an inherent, latent capacity for modifying their structure and are at the same time oleophobic and oleophilic. The invention also embraces processes for the preparation of the shaped articles described and processes for modifying their structure. The invention also relates to the use of shaped articles according to the invention.Type: GrantFiled: July 27, 1982Date of Patent: December 10, 1985Assignee: Hoechst AktiengesellschaftInventors: Axel Walch, Walter Seifried, Wolfgang Michel, Jurgen Kuhls, Jurgen Wildhardt
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Patent number: 4543221Abstract: Improved cellulose semipermeable hollow fibers useful in detoxifying blood during hemodialysis or hemofiltration treatments. The cellulose fibers are fine, capillary fibers that are made by melt extrusion of certain cellulose ester polyol melt spin compositions into self-supporting gelled fibers. The cellulose ester gelled fibers are subsequently chemically converted into cellulose fibers by deacetylation, in aqueous alkali solution. The product fibers exhibit improved wet intrinsic tensile strength and higher water permeability characteristics than heretofore known cellulose fibers made from cellulose ester spin compositions.The invention includes the method of making the improved fibers and separatory cells such as hemodialyzers or hemofilters which contain the improved fibers in a gamma ray sterilized condition.Type: GrantFiled: October 21, 1981Date of Patent: September 24, 1985Assignee: CD Medical, Inc.Inventors: David T. Chen, Robert D. Mahoney
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Patent number: 4528157Abstract: Feeding of molten plastic strands into a discharge trough. At its upper end the discharge trough includes a slidably movable segment that can be extended behind the fall line of the strands as they emerge from nozzles. In its operating position, the extended segment catches the strands, and can be moved into a fore-running or non-operating position permitting free passage of the strands at the side of the discharge trough. A separational element is associated with the movable segment. As the segment is moved through the fall line of the strands, the separational element acts upon the strands and effects the desired separation. The strands which enter the discharge trough are cooled and ultimately fed to a granulator.Type: GrantFiled: February 15, 1983Date of Patent: July 9, 1985Assignee: Automatik Apprate-Maschinenbau H. Hench GmbHInventors: Horst H. Lettner, Friedrich Hunke, Hans Hench
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Patent number: 4524193Abstract: A modacrylic fiber comprising a copolymer containing acrylonitrile, at least one of vinyl chloride and vinylidene chloride, and a sulfo group-containing vinyl monomer having a relative reactivity of at least 1 to acrylonitrile, in a specific ratio. The copolymer is prepared by polymerizing the monomers, while adding the sulfo group-containing vinyl monomer to the polymerization system under the following condition:16<Y-X<83wherein X and Y are percentages of the amount of a polymer produced at the time of starting the addition and the amount of a polymer produced at the time of finishing the addition, respectively, based on the amount of the whole polymer to be produced. The fiber has an excellent flame resistance and an excellent devitrification preventing property.Type: GrantFiled: September 21, 1982Date of Patent: June 18, 1985Assignee: Kanegafuchi Kagaku Kogyo Kabushiki KaishaInventors: Kaoru Yamazaki, Shunichiro Kurioka, Mitsuya Sakata, Takahiro Ogawa