Patents by Inventor Janet L. M. Johnson

Janet L. M. Johnson 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).

  • Glass-ceramic compositions for dental constructs
    Patent number: 4652312
    Abstract: Tetrasilicic fluormica glass-ceramic compositions particularly suited for use in the preparation of dental restorations, consisting essentially in weight percent of about 45-70% SiO.sub.2, 13-30% MgO, 5-20% K.sub.2 O, 0-2% Al.sub.2 O.sub.3, 0-7% ZrO.sub.2, 4-9% F and 1-4% BaO, and porcelain-glazed dental restorations prepared therefrom, are described.
    Type: Grant
    Filed: November 4, 1985
    Date of Patent: March 24, 1987
    Assignee: Corning Glass Works
    Inventors: David G. Grossman, Janet L. M. Johnson