Opinion ID: 427227
Heading Depth: 2
Heading Rank: 2

Heading: The Fromson Patent

Text: 4 In the 1950's, Fromson was in the business of selling metals and began, through Ano-Coil Corporation, to manufacture and sell anodized aluminum. In anodization, aluminum is coated with oxide while it is the anode in an electrolytic bath wherein it is subjected to an electric current, whence the term anodized. The anodized aluminum was used in articles such as television antennas, furniture tubing, and nameplates. 5 Fromson, with no background in lithography, conceived of using anodized aluminum as a replacement for non-anodized aluminum in the plate taught by Jewett. His invention according to the Fromson patent improves the Jewett plate in a number of ways. It enables use in preparation of the plate of light-sensitive compounds other than diazo compounds. It enables the coating to absorb nitrogen-containing materials released by the light-sensitive compounds when exposed to light. Also, as the district court found, the Fromson plate enjoys improved corrosion resistance and a longer press life. 6 Fromson filed his application for patent in May, 1963, and the patent issued in May, 1965, containing eleven product and five process claims. Claim 1 is representative of the product claims: 7 1. A sensitized photographic printing plate comprising an aluminum sheet having a surface which has been treated to form an aluminum oxide coating on said surface, a water-insoluble, hydrophilic, organophobic layer on said sheet resulting from the reaction of the aluminum oxide coating and an alkali metal silicate applied to said coating, and a light-sensitive coating over said layer [e.g., diazo resin] having one solubility in relation to a solvent in a state before exposure to light and another solubility in relation to said solvent in another state after exposure to light, said light-sensitive material being soluble in said solvent in one of said states and being insoluble in said solvent and in water, hydrophobic and organophilic in its other state. 8 Claim 12 is the sole independent process claim: 9 12. The process of making a sensitized photographic plate comprising the steps of applying to an aluminum sheet having a coating of aluminum oxide, a water-solution of an alkali metal silicate to cause the silicate to react with the aluminum oxide to form a water-insoluble, hydrophilic, organophobic layer on said sheet, drying the layer, and applying over the dry layer a light-sensitive coating having one solubility in relation to a solvent in a state before exposure to light and another solubility in relation to said solvent in another state after exposure to light, said light-sensitive material being soluble in said solvent in one of said states and being insoluble in said solvent and in water, hydrophobic and organophilic in its other state.