Patents Assigned to George H. Butterfield and Son
  • Composition for hard type contact lens with wettable surface
    Patent number: 3948871
    Abstract: A contact lens of the hard type, but exhibiting wettable surface characteristics, is produced from a polymer composition consisting essentially of about 90% by weight methyl methacrylate and about 10% by weight of neutralized hydroxy ethyl methacrylate.
    Type: Grant
    Filed: February 4, 1974
    Date of Patent: April 6, 1976
    Assignee: George H. Butterfield and Son
    Inventors: George H. Butterfield, Jr., George H. Butterfield, Sr., deceased, by David Gordon, executor