Appeal No. 1996-3470
Application 08/313,179
aluminum. The claimed process requires that the metal surface is
contacted with a phosphating solution containing zinc ions;
copper ions; phosphate ions; manganese ions; and importantly, at
least one member selected from the group consisting of
hydroxylamine salts, hydroxylamine complexes and hydroxylamine.
Such a phosphating solution provides a crystalline coating on the
metal surfaces containing an edge length of the phosphate
crystals of from 0.5 to 10 microns. The coating produced by the
process of the claimed invention is said to provide a firm
lacquer adhesion and excellent corrosion protection to the metal
surfaces treated.
As evidence of obviousness of the claimed invention, the
examiner relies on the combined disclosures of Gehmecker, Kramer,
and Müller. Similar to appellants' claimed process, Gehmecker
discloses a process for the production of nickel-free phosphate
coatings (column 2, lines 48-54) on steel, galvanized steel, and
aluminum surfaces which phosphate coatings provide advantageous
corrosion protection for the metal surfaces. Additionally,
Gehmecker's phosphate coatings are advantageously used to prepare
the metal surfaces for a subsequent lacquer coating. See column
4, lines 57 through 64 of the reference. Gehmecker's phosphating
solution, which is substantially free of nickel, contains zinc
3
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