Patents Represented by Attorney, Agent or Law Firm George A. Frank
  • Polyurethaneureas and spandex made therefrom
    Patent number: 5948875
    Abstract: New polyurethaneurea polymers and spandex made therefrom, based on certain glycols, MDI and a diamine chain extender mixture containing high proportions of 2-methyl-1,5-pentanediamine and prepared at selected capping ratios, are provided.
    Type: Grant
    Filed: March 26, 1998
    Date of Patent: September 7, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Hong Liu, Robert Otto Waldbauer, Jr.
  • Method for making stretch leather laminates and finished articles containing such laminates
    Patent number: 5932056
    Abstract: A method for making a stretch leather laminate of stretch fabric and stretchable leather so that the high-stretch directions of the fabric and the leather are substantially aligned in a preselected region of the leather. Finished articles containing such laminates are also provided.
    Type: Grant
    Filed: October 9, 1997
    Date of Patent: August 3, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Moishe Mark, Edward Lee Meiser
  • Process and apparatus for knitting fabric with non-elastic yarn and bare elastomeric yarn and sweater knit fabric construction
    Patent number: 5931023
    Abstract: A sweater knit fabric containing hard yarn plaited together with bare elastomeric yarn is provided. The elastomeric yarn has substantially uniform draft along each course in the fabric. The fabric is made by a process in which the bare elastomeric yarn is fed under substantially uniform tension to a knitting machine in which yarn demand fluctuates as the fabric is knitted. Sweater knit fabrics are useful in making garments such as sweaters, vests, dresses, pants, skirts, shirts and caps.
    Type: Grant
    Filed: October 9, 1996
    Date of Patent: August 3, 1999
    Inventors: Ernesto Brach, Isaac Brach
  • Apparatus for splicing threadlines
    Patent number: 5887322
    Abstract: An apparatus and method for splicing a moving threadline to a stationary threadline utilizing adhesive tapes is provided.
    Type: Grant
    Filed: April 2, 1998
    Date of Patent: March 30, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Richard John Hartzheim, David Reinhold Roland, Thomas Wilford Teerlink
  • Spandex blended in natural rubber
    Patent number: 5872186
    Abstract: Staple-length fibers of spandex are blended into compounded natural rubber to improve the mechanical properties of the rubber.
    Type: Grant
    Filed: February 16, 1996
    Date of Patent: February 16, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Pei Pei Ang
  • Process for polyesterurethaneurea thin-walled articles
    Patent number: 5728340
    Abstract: Certain polyester-based polyurethaneureas in solutions of organic solvent at a 12 to 20% concentration are particularly suited for use in a mandrel-dipping process for producing thin-walled elastic articles, such as surgical gloves, which are more resistant to puncture and tear than conventional surgical gloves made from rubber latex.
    Type: Grant
    Filed: July 19, 1996
    Date of Patent: March 17, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Richard Lewis Dreibelbis, Nathan Eli Houser, Jacob Lahijani
  • Hydrometallurgical extraction and recovery of copper, gold, and silver via cyanidation and electrowinning
    Patent number: 5667557
    Abstract: A hydrometallurgical process for treating copper feed materials containing gold and/or silver by simultaneously leaching copper, gold and/or silver into an aqueous cyanide solution, recovering copper in metallic form by electrowinning and regenerating cyanide ions is provided, wherein high current efficiencies are achieved at high current densities and at low copper concentrations.
    Type: Grant
    Filed: September 26, 1995
    Date of Patent: September 16, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Christopher Andrew Fleming, Walther G. Grot, John Anton Thorpe
  • Method for preparing low-concentration polyaluminosilicate microgels
    Patent number: 5648055
    Abstract: An improved method and apparatus for preparing low-concentration polyaluminosilicate microgels from a water soluble silicate and a strong acid in which the silicate and acid are mixed at a rate to produce a Reynolds number of at least 4000, the mixture is aged and then diluted to a silica concentration of not more than 1.0 wt. %. The method achieves reduced silica deposition during the preparation of the microgels.
    Type: Grant
    Filed: October 25, 1995
    Date of Patent: July 15, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Robert Harvey Moffett, John Derek Rushmere
  • Surface coating compositions containing fluoroalkyl esters of unsaturated fatty acids
    Patent number: 5637657
    Abstract: Perfluoroalkenoate esters containing at least two double bonds and coasting compositions, having durable advancing and receding hexadecane contact angles, containing such esters with alkyd or urethane resins are provided.
    Type: Grant
    Filed: September 18, 1995
    Date of Patent: June 10, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Douglas R. Anton
  • Process for preparing water soluble polyaluminosilicates
    Patent number: 5626721
    Abstract: An improved method for the production of water soluble polyaluminosilicate microgels, formed by the reaction of solutions of alkali metal silicates with solutions of acids containing dissolved aluminum compounds, is provided.
    Type: Grant
    Filed: December 6, 1995
    Date of Patent: May 6, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: John D. Rushmere, Robert H. Moffett
  • Process for the manufacture of paper
    Patent number: 5595630
    Abstract: A process for producing paper, utilizing a combination of anionic and cationic aluminum compound additives and providing superior freeness and diminished turbidity, is provided.
    Type: Grant
    Filed: August 31, 1995
    Date of Patent: January 21, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Robert H. Moffett
  • Process for producing ortho-nitro aromatic acids by oxidation of ortho-nitroalkylaromatic compounds
    Patent number: 5591890
    Abstract: A process for preparing o-nitroaromatic acids by direct oxidation of the corresponding o-nitroalkylaromatic compounds, utilizing salts of certain catalytic metals in the presence of an oxygen-containing gas and an aliphatic aldehyde or ketone at elevated temperature and pressure, is provided. The process allows catalyst recovery and reuse.
    Type: Grant
    Filed: November 3, 1995
    Date of Patent: January 7, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Stephen E. Jacobson
  • Process for treating iron-containing sulfidic rocks and ores
    Patent number: 5587001
    Abstract: A process is provided for pretreating iron-containing sulfidic ores of precious metals or other such sulfidic rocks with a source of manganate ions prior to lixiviation to form a layer of manganese oxide, thereby reducing the consumption of lixiviation reagents or reducing acid rock drainage.
    Type: Grant
    Filed: April 28, 1995
    Date of Patent: December 24, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Nadine H. C. De Vries
  • Paper formation
    Patent number: 5584966
    Abstract: An improved method of paper formation, utilizing a combination of polysilicate microgel, anionic and cationic polymers with the optional utilization of an aluminum salt, is provided.
    Type: Grant
    Filed: February 21, 1995
    Date of Patent: December 17, 1996
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Robert H. Moffett
  • Process for preparing water soluble polyaluminosilicates
    Patent number: 5543014
    Abstract: An improved method for the production of water soluble polyaluminosilicate microgels, formed by the reaction of solutions of alkali metal silicates with solutions of acids containing dissolved aluminum compounds, is provided.
    Type: Grant
    Filed: August 16, 1995
    Date of Patent: August 6, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: John D. Rushmere, Robert H. Moffett
  • Method for preparing low-concentration polysilicate microgels
    Patent number: 5503820
    Abstract: An improved method for preparing low-concentration polysilicate microgels from a water soluble silicate and a strong acid in which the silicate and acid are mixed at a rate to produce a Reynolds number of at least 4000, the mixture is aged and then diluted to a silica concentration of not more than 1.0 wt. %. The method achieves reduced silica deposition during the preparation of the microgels.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: April 2, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Robert H. Moffett, John D. Rushmere
  • Preparation of isophorone diamine
    Patent number: 5491264
    Abstract: Isophorone diamine is prepared from isophorone nitrile by imination using a supported heteropoly acid catalyst to form the ketimine followed by the reduction of the ketimine to form the diamine.
    Type: Grant
    Filed: September 12, 1994
    Date of Patent: February 13, 1996
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Frank E. Herkes, Kostantinos Kourtakis
  • Enhancement of gold lixiviation using nitrogen and sulfur heterocyclic aromatic compounds
    Patent number: 5484470
    Abstract: An improved process for dissolving gold metal in ligand and oxidant lixiviation systems, wherein the solubility of gold is enhanced by the addition of heterocyclic aromatic compounds containing nitrogen or sulfur in the ring.
    Type: Grant
    Filed: July 28, 1994
    Date of Patent: January 16, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Sigridur S. Kristjansdottir, Jeffery S. Thompson
  • Process for preparing water soluble polyaluminosilicates
    Patent number: 5482693
    Abstract: An improved method for the production of water soluble polyaluminosilicate microgels, formed by the reaction of solutions of alkali metal silicates with solutions of acids containing dissolved aluminum compounds, is provided.
    Type: Grant
    Filed: March 14, 1994
    Date of Patent: January 9, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: John D. Rushmere, Robert H. Moffett
  • Process for preparing water soluble polyaluminosilicates
    Patent number: 5470435
    Abstract: An improved method for the production of water soluble polyaluminosilicate microgels, formed by the reaction of solutions of alkali metal silicates with solutions of acids containing dissolved aluminum compounds, is provided.
    Type: Grant
    Filed: November 23, 1994
    Date of Patent: November 28, 1995
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: John D. Rushmere, Robert H. Moffett