Patents Represented by Law Firm Hirons & Rodgers
  • Compositions and processes for producing chromium conversion coatings on surfaces of zinc or cadmium
    Patent number: RE29827
    Abstract: In a process for producing a chromium protective coating on a zinc or cadmium surface the surface has applied thereto an aqueous composition including chromium, perchlorate and fluoride ions with the chromium ion being the only metal ion present before application to the surface. The apparatus by which the composition is applied to a strip moving through an application station includes a provision for rinsing the surface if the strip is stopped for longer than a predetermined time in the station.
    Type: Grant
    Filed: November 1, 1976
    Date of Patent: November 7, 1978
    Assignee: Dominion Foundries and Steel, Limited
    Inventors: Michael W. Prust, Wayne C. Glassman