Patents by Inventor Douglas A. Hoffmann

Douglas A. Hoffmann has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10407342
    Abstract: A method of forming high strength glass fibers in a refractory-lined glass melter, products made there from and batch compositions suited for use in the method are disclosed. The glass composition for use in the method of the present invention is up to about 64-75 weight percent SiO2, 16-24 weight percent Al2O3, 8-12 weight percent MgO and 0.25-3 weight percent R2O, where R2O equals the sum of Li2O and Na2O, has a fiberizing temperature less than about 2650° F., and a ?T of at least 80° F. By using oxide-based refractory-lined furnaces the cost of production of glass fibers is substantially reduced in comparison with the cost of fibers produced using a platinum-lined melting furnace. High strength composite articles including the high strength glass fibers are also disclosed.
    Type: Grant
    Filed: June 20, 2017
    Date of Patent: September 10, 2019
    Assignee: OCV Intellectual Capital, LLC
    Inventors: Peter B. McGinnis, Douglas A. Hoffmann
  • Publication number: 20170283310
    Abstract: A method of forming high strength glass fibers in a refractory-lined glass melter, products made there from and batch compositions suited for use in the method are disclosed. The glass composition for use in the method of the present invention is up to about 64-75 weight percent SiO2, 16-24 weight percent Al2O3, 8-12 weight percent MgO and 0.25-3 weight percent R2O, where R2O equals the sum of Li2O and Na2O, has a fiberizing temperature less than about 2650° F., and a ?T of at least 80° F. By using oxide-based refractory-lined furnaces the cost of production of glass fibers is substantially reduced in comparison with the cost of fibers produced using a platinum-lined melting furnace. High strength composite articles including the high strength glass fibers are also disclosed.
    Type: Application
    Filed: June 20, 2017
    Publication date: October 5, 2017
    Inventors: Peter B. McGinnis, Douglas A. Hoffmann
  • Publication number: 20110000263
    Abstract: A method of forming high strength glass fibers in a refractory lined glass melter is disclosed. The refractory lined melter is suited to the batch compositions disclosed for the formation high modulus, and high-strength glass fibers. The glass composition for use in the method of the present invention is up to about 70.5 Weight % SiO2, 24.5 weight % Al2O3, 22 weight % alkaline earth oxides and may include small amounts of alkali metal oxides and ZrO2. Oxide based refractories included alumina, chromic oxide, silica, alumina-silica, zircon, zirconia-alumina-silica and combinations thereof. By using oxide based refractory lined furnaces the cost of production of glass fibers is substantially reduced in comparison with the cost of fibers using a platinum lined melting furnace. Fibers formed by the present invention are also disclosed.
    Type: Application
    Filed: September 13, 2010
    Publication date: January 6, 2011
    Applicant: OCV INTELLECTUAL CAPITAL, LLC
    Inventors: Douglas A. Hoffmann, Peter B. McGinnis
  • Patent number: 7823417
    Abstract: A method of forming high strength glass fibers in a refractory lined glass melter is disclosed. The refractory lined melter is suited to the batch compositions disclosed for the formation high modulus, and high-strength glass fibers. The glass composition for use in the method of the present invention is up to about 70.5 Weight % SiO2, 24.5 weight % Al2O3, 22 weight % alkaline earth oxides and may include small amounts of alkali metal oxides and ZrO2. Oxide based refractories included alumina, chromic oxide, silica, alumina-silica, zircon, zirconia-alumina-silica and combinations thereof. By using oxide based refractory lined furnaces the cost of production of glass fibers is substantially reduced in comparison with the cost of fibers using a platinum lined melting furnace. Fibers formed by the present invention are also disclosed.
    Type: Grant
    Filed: November 4, 2005
    Date of Patent: November 2, 2010
    Assignee: OCV Intellectual Capital, LLC
    Inventors: Douglas A. Hoffmann, Peter B. McGinnis