Patents by Inventor Doris Hathaway

Doris Hathaway 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: 8524150
    Abstract: A dental alloy with a high gold content that is devoid of palladium and copper. To achieve high mechanical stability, the dental alloy contains between 75 and 95 wt. % Au, between 5 and 20 wt. % Pt, between 0.5 and 3.5 wt. % Zn and/or Sn and/or In, between 0.1 and 0.8 wt. % of an element of a group I, in addition to a single particle refiner of a group II. The weight fraction of the element of group I is between 2 and 6 times that of the single particle refiner of group II, and one element of group I is represented by Nb or Ta or Ti or V and the particle refiner of group II is represented by Ir or Rh.
    Type: Grant
    Filed: October 13, 2005
    Date of Patent: September 3, 2013
    Assignee: Degudent GmbH
    Inventors: Jochen Bauer, Lothar Volkl, Doris Hathaway, Angela Klaus, Martin Schuster, Rudi Steinke
  • Publication number: 20080152535
    Abstract: A dental alloy with a high gold content that is devoid of palladium and copper. To achieve high mechanical stability, the dental alloy contains between 75 and 95 wt. % Au, between 5 and 20 wt. % Pt, between 0.5 and 3.5 wt. % Zn and/or Sn and/or In, between 0.1 and 0.8 wt. % of an element of a group I, in addition to a single particle refiner of a group II. The weight fraction of the element of group I is between 2 and 6 times that of the single particle refiner of group II, and one element of group I is represented by Nb or Ta or Ti or V and the particle refiner of group II is represented by Ir or Rh.
    Type: Application
    Filed: October 13, 2005
    Publication date: June 26, 2008
    Applicant: Degudent GmbH
    Inventors: Jochen Bauer, Lothar Volkl, Doris Hathaway, Angela Klaus, Martin Schuster, Rudi Steinke
  • Patent number: 5695714
    Abstract: Gold-palladium alloys with a high gold content for dental applications should, for reasons of biocompatibility, not contain any toxically dubious components. For particularly corrosion-resistant and biocompatible Type 4 alloys, tin is needed as the only base-metal component in amounts between 0.7 and 5.8 wt % if one remains within defined limits in a palladium-tin diagram of FIG. 1, for Pt values less than 2%. Such alloys contain, in addition to gold and tin, 6 to 25 wt % palladium, 0 to 12 wt % platinum and 0 to 2 wt % of at least one of iridium, rhodium and/or ruthenium.
    Type: Grant
    Filed: July 20, 1994
    Date of Patent: December 9, 1997
    Assignee: Degussa Aktiengesellschaft
    Inventors: Bernd Kempf, Doris Hathaway, Gernot Schoeck, Hans-Martin Ringelstein, Bernd Meier
  • Patent number: 5560742
    Abstract: Gold-free palladium-silver alloys for dentures [dental prostheses] which alloys can be veneered without color changes with dental ceramics and can be easily removed from the mold after the casting contain 45 to 80% by weight palladium, 7 to 50% by weight silver, 0 to 5% by weight gold, 0 to 5% by weight tin, 0 to 5% by weight indium, 0 to 3% by weight zinc, 0 to 2% by weight copper, 0 to 1% by weight ruthenium, iridium and/or rhenium, 0 to 7% by weight gallium, 0 to 5% by weight cobalt and 0 to 3% by weight germanium, whereby of the elements gallium, cobalt and germanium at least two must be present with contents totalling 2 to 9% by weight.
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: October 1, 1996
    Assignee: Degussa AG
    Inventors: Werner Groll, Gernot Schoeck, Doris Hathaway, Manfred Stuemke
  • Patent number: 5298218
    Abstract: Palladium based dental alloys do not show unaesthetic discolorations after ceramic firing if said alloys contain 66-85% by weight palladium, 1-20% by weight gold; 0-4% by weight silver; 0-4% by weight of at least one of platinum, iron and/or cobalt; 0.5-7% by weight of each of gallium, tin and indium, whereby the amount of said components total 9-14% by weight; 0-2% by weight germanium and/or zinc; and 0-1% by weight iridium, ruthenium and/or rhenium.
    Type: Grant
    Filed: September 4, 1992
    Date of Patent: March 29, 1994
    Assignee: Degussa Aktiengesellschaft
    Inventors: Werner Groll, Doris Hathaway, Bernd Kempf, Gernot Schock
  • Patent number: 4859412
    Abstract: An economical alloyed powder for dental amalgams exhibiting good working properties is obtained from pressed and sintered molded bodies by mechanical comminution. The formed body is produced by mixing and pressing powders of elemental silver, copper and tin with a subsequent sintering between 150.degree. C. and the solidus temperature of the alloy being formed. The sintering is performed until a homogeneous distribution of the tin has been achieved in the silver and copper particles.
    Type: Grant
    Filed: May 23, 1988
    Date of Patent: August 22, 1989
    Inventors: Werner Groll, Doris Hathaway, Gernot Schock
  • Patent number: 4681735
    Abstract: Economical but readily workable palladium alloys for baking on dental ceramics consist of 60 to 80% palladium, 0 to 8% gold, 0 to 5% platinum, 0 to 1% ruthenium and/or rhenium, 2 to 20% copper, 1 to 12% tin and/or indium, 0.2 to 5% of at least one of the elements tungsten, molybdenum, niobium, and tantalum, and 0 to 15% cobalt, with the proviso that the sum of tin and indium must be between 5 and 14%.
    Type: Grant
    Filed: September 12, 1985
    Date of Patent: July 21, 1987
    Assignee: Degussa Aktiengesellschaft
    Inventors: Werner Groll, Gernot Schock, Doris Hathaway, Rudolf Wagner