Patents Represented by Attorney P. Michael Walker
  • Patent number: 5856428
    Abstract: An aromatic polyamide resin composition composed of two types of aromatic polyamide (A) and (B), where (A) is an aromatic polyamide wherein the molar ratio of aromatic polyamide with respect to the monomer components that constitute the polyamide is 0.4 or greater, and (B) is an aromatic polyamide containing an aromatic monomer as the monomer component that constitutes the polyamide and has a recrystallization temperature that is lower than that of the aromatic polyamide (A), where said aromatic polyamide resin composition has a recrystallization temperature that is 10.degree. C. or more lower than the recrystallization temperature of the aromatic polyamide (A).Merit:The aromatic polyamide composition of the present invention has the high heat resistance characteristic of aromatic polyamides, superior dimensional stability with respect to water absorption, and maintenance of physical stability and chemical resistance, while providing improved molding characteristics.
    Type: Grant
    Filed: October 1, 1996
    Date of Patent: January 5, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Ryuichi Hayashi, Reiko Koshida
  • Patent number: 5618865
    Abstract: This invention relates to flame retardants for polyester and polyamide compositions, and specifically relates to compositions containing (1) about 30 to about 70 weight percent of a polyester or a synthetic, aliphatic polyamide; (2) about 15 to about 40 weight percent of glass or mineral reinforcing agent; and (3) a flame retardant of (a) about 20 to about 30 weight percent of melamine phosphate and up to about 10 weight percent of a charring catalyst; (b) about 15 to about 30 weight percent of melamine phosphate, up to about 10 weight percent of a charring catalyst and up to about 10 weight percent of a char former; (c) about 25 to about 30 weight percent of melamine pyrophosphate; (d) about 15 to about 30 weight percent of melamine pyrophosphate and up to about 10 weight percent of a charring catalyst; or (e) about 15 to about 30 weight percent of melamine pyrophosphate, up to about 10 weight percent of a charring catalyst and up to about 10 weight percent of a char former, wherein all percents by weight ar
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: April 8, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Marvin M. Martens, Robert V. Kasowski
  • Patent number: 5618864
    Abstract: Flame retardant polyamide compositions are provided which contain melamine as the flame retardant. Flame retardant benefits are particularly realized by a composition which is a blend of melamine with a copolymer of polyamide-6.6 and 6. Use of heat stabilizers in the preferred compositions minimizes the thermal aging properties of the copolymer compared to polyamide-6.6.
    Type: Grant
    Filed: October 5, 1995
    Date of Patent: April 8, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Trevor L. Court
  • Patent number: 5602200
    Abstract: A polymeric composition includes a polyamide; an unmodified polypropylene or unmodified polyethylene; optionally a carboxylic acid or maleic anhydride-grafted ethylene-propylene-diene elastomer; and a carboxylic acid or maleic anhydride-grafted polyethylene or polypropylene.
    Type: Grant
    Filed: August 25, 1995
    Date of Patent: February 11, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Rolf B. Wissmann
  • Patent number: 5417871
    Abstract: Refrigerant compositions include mixtures of difluoromethane and isobutane, butane, propylene or cyclopropane; pentafluoroethane and propylene or cyclopropane; 1,1,2,2-tetrafluoroethane and propane; 1,1,1,2-tetrafluoroethane and cyclopropane; 1,1,1-trifluoroethane and DME or propylene; 1,1-difluoroethane and propane, isobutane, butane or cyclopropane; fluoroethane and propane or cyclopropane; 1,1,1,2,2,3,3-heptafluoropropane and butane, cyclopropane, DME, isobutane or propane; or 1,1,1,2,3,3,3-heptafluoropropane and butane, cyclopropane, isobutane or propane.
    Type: Grant
    Filed: March 11, 1994
    Date of Patent: May 23, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Barbara H. Minor, Donald B. Bivens, Brooks S. Lunger
  • Patent number: 5387357
    Abstract: Constant boiling azeotropic or azeotrope-like compositions of ammonia and 1,1,1,2-tetrafluoroethane, 1,1,2,2-tetrafluoroethane, difluoromethane, pentafluoroethane or 1,1,1,2,3,3,3-heptafluoropropane are disclosed that are useful as refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, expansion agents for polyolefins and polyurethanes and as power cycle working fluids.
    Type: Grant
    Filed: September 25, 1992
    Date of Patent: February 7, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Mark B. Shiflett, Akimichi Yokozeki
  • Patent number: 5290466
    Abstract: Compositions of difluoromethane, 1,1,1,2-tetrafluoroethane, and 1,1,2,2-tetrafluoroethane are useful as refrigerants, aerosol propellants, heat transfer edia, gaseous dielectrics, fire extinguishing agents, expansion agents for polymers such as polyolefins and polyurethanes, and as power cycle fluids.Near azeotropic compositions comprise admixtures of effective amounts of difluoromethane and tetrafluoroethane to form a near azeotropic composition. Such compositions are useful as refrigerants, cleaning agents, expansion agents for polyolefins and polyurethanes, refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, power cycle working fluids, polymerization media, particulate removal fluids, carrier fluids, buffing abrasive agents, and displacement drying agents.
    Type: Grant
    Filed: October 16, 1992
    Date of Patent: March 1, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Mark B. Shiflett
  • Patent number: 5254309
    Abstract: A sterilant mixture comprising 15 to 30 mole percent ethylene oxide and 70 to 85 mole percent 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) and a sterilization method using same.
    Type: Grant
    Filed: February 2, 1993
    Date of Patent: October 19, 1993
    Assignees: E. I. Du Pont de Nemours and Company, Praxair Tech. Inc.,
    Inventors: Vinci M. Felix, Tuneen Chisolm-Carter
  • Patent number: 5250208
    Abstract: Azeotropic or azeotrope-like compositions of effective amounts of 1,1,2,2,3,3,4,4,-octofluorobutane; trans-1,2-dichloroethylene, cis-1,2-dichloroethylene, 1,1-dichloroethane, or 1,3-dichloro-1,2,2,3,3-HCFC-225cb; and an alcohol such as methanol, ethanol, or isopropanol, to form an azeotropic or azeotrope-like composition are disclosed that are useful as cleaning agents, refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, expansion agents for polyolefins and polyurethanes and as power cycle working fluids.
    Type: Grant
    Filed: April 2, 1992
    Date of Patent: October 5, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Abid N. Merchant, Janet C. Sung
  • Patent number: 5248433
    Abstract: Constant boiling azeotropic or azeotrope-like mixtures of octafluoropropane and fluoroethane are useful as refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, expansion agents for polyolefins and polyurethanes and as power cycle working fluids.
    Type: Grant
    Filed: April 30, 1992
    Date of Patent: September 28, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Vinci M. Felix, Mark B. Shiflett
  • Patent number: 5236611
    Abstract: Constant boiling compositions of perfluoropropane and trifluoroethane that are useful as refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, expansion agents for polyolefins and polyurethanes and as power cycle working fluids.
    Type: Grant
    Filed: October 28, 1991
    Date of Patent: August 17, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Mark B. Shiflett
  • Patent number: 5232618
    Abstract: Substantially constant boiling mixtures of difluoromethane and 1,1,1-trifluoroethane or perfluoroethane are useful as refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, and expansion agents for polymers.
    Type: Grant
    Filed: September 30, 1991
    Date of Patent: August 3, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Mark B. Shiflett
  • Patent number: 5221493
    Abstract: Azeotropic mixtures of HFC-338pcc and an alcohol such as methanol, ethanol, isopropanol or N-propanol, or a ketone such as acetone, are disclosed that are useful as cleaning agents, refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, expansion agents for polyolefins and polyurethanes, power cycle working fluids, polymerization media, particulate removal fluids, carrier fluids, and displacement drying agents.
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: June 22, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Abid N. Merchant, Allen C. Sievert, Akimichi Yokozeki, Janet C. Sung
  • Patent number: 5215730
    Abstract: A method for improving abrasion resistance of sodium perborate tetrahydrate crystals prepared by reacting sodium metaborate with hydrogen peroxide in an aqueous slurry crystal growth medium, the improvement including highly supersaturating the aqueous slurry crystal growth medium. Also, an agent such as an excess of caustic may be added to the aqueous crystal growth medium to limit the growth rate of individual crystals.
    Type: Grant
    Filed: October 29, 1991
    Date of Patent: June 1, 1993
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Janet M. Rogers, Linda F. Tolbert, Harold F. Porter, deceased, Daniel A. Green
  • Patent number: 5196137
    Abstract: Azeotropic mixtures of 1,1,1,2,3,4,4,5,5,5-decafluoropentane (HFC-43-10mee) and trans-1,2-dichloroethylene, cis-1,2-dichloroethylene or 1,1-dichloroethane are useful as cleaning agents, expansion agents for polyolefins and polyurethanes, refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, power cycle working fluids, polymerization media, particulate removal fluids, carrier fluids, buffing abrasive agents, and displacement drying agents.
    Type: Grant
    Filed: October 1, 1991
    Date of Patent: March 23, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Abid N. Merchant
  • Patent number: 5194657
    Abstract: A process for preparing an alpha aminonitrile comprises providing a cyclic or acyclic aliphatic ketone in a reactor, adding ammonia to the reactor, mixing the ketone and the ammonia, and adding hydrogen cyanide to the reactor to convert the hydrogen cyanide to an aminonitrile. Preferably, the reactor is purged with ammonia before the addition of hydrogen cyanide. The hydrogen cyanide may be added to the reactor at a constant rate, or it may be added to the reactor at a rate that decreases over time. A portion of the ketone may be added to the reactor during the addition of the hydrogen cyanide to the reactor.
    Type: Grant
    Filed: December 9, 1991
    Date of Patent: March 16, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Ronald J. McKinney, Robert N. McGill
  • Patent number: 5194170
    Abstract: Azeotropic or azeotrope-like compositions of effective amounts of 1,1,2,2,3,3,4,4-octafluorobutane and trans-1,2-dichloroethylene; cis-1,2-dichloroethylene; or 1,1-dichloroethane to form an azeotropic or azeotrope-like composition are disclosed that are useful as cleaning agents, refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, expansion agents for polyolefins and polyurethanes and as power cycle working fluids.
    Type: Grant
    Filed: April 2, 1992
    Date of Patent: March 16, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Abid N. Merchant, Janet C. Sung
  • Patent number: 5139763
    Abstract: A stable, nonhygroscopic potassium monopersulfate composition comprising KHSO.sub.5, KHSO.sub.4 and K.sub.2 SO.sub.4 having a composition represented by a point within the closed curve of FGHIF of FIG. 1.A process for preparing a stable, nonhygroscopic potassium monopersulfate composition having the following formula:(KHSO.sub.5).sub.x.(KHSO.sub.4).sub.y.(K.sub.2 SO.sub.4).sub.zwhere x+y+z=1 and x=0.48-0.64, y=0.15-0.37, and z=0.15-0.37 includes providing Caro's acid having a molar ratio of H.sub.2 SO.sub.5 /H.sub.2 SO.sub.4 of 1.6 or more and a water content of 40 to 65 weight percent, partially neutralizing the Caro's acid with a basic potassium compound to form a reaction mixture having a potassium to sulfur ratio (K/S) of 1.15 to 1.25 and a molar ratio of KHSO.sub.5 /(KHSO.sub.4 +K.sub.2 SO.sub.4) greater than 1.0, adding the reaction mixture to a solution having a molar ratio of KHSO.sub.5 /(KHSO.sub.4 +K.sub.2 SO.sub.4) greater than 2.5 to produce a final mixture having a molar ratio of KHSO.sub.
    Type: Grant
    Filed: March 6, 1991
    Date of Patent: August 18, 1992
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Bijan Amini
  • Patent number: 5118727
    Abstract: Binder compositions are disclosed that include silica aquasols having silica that is metal-modified to include a monolayer or less of a metal such as aluminum, tin, zinc or lead, and deionized to a pH of 2,5-7.0 and a water soluble polymer such as poly(vinyl alcohol).An adhesive that includes a silica aquasol, an oxygen-moiety containing polymer, and clay, the surface of the silica being modified to include a metal, and the silica aquasol being deionized to a pH of 2.5 to 7.
    Type: Grant
    Filed: March 13, 1991
    Date of Patent: June 2, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: William O. Roberts, Elizabeth R. Griffin
  • Patent number: 4981572
    Abstract: An electrode unit for use in an analyzer of blood and of liquids includes a cylindrical outer housing having open ends and a pair of top hat end plate bushings each having a central bore and a plug portion, the bushings being positioned in each end of the housing with the plug portion directed into the housing to form a filling chamber with the inner surface of the housing. A sodium glass capillary tube is mounted in the bores of the bushings. An annular groove is formed in an end flange portion of each bushing so that a connecting alignment ring may seat in the bushing annular grooves of two adjacent electrode units to center the electrode units.
    Type: Grant
    Filed: June 16, 1988
    Date of Patent: January 1, 1991
    Assignee: Glastron, Inc.
    Inventors: Henry C. Easmunt, Benito Sopranzetti, Jr.