Process for coating metallic surfaces with a multicomponent aqueous composition

A process consisting of coating a metallic surface with a composition, said composition consisting of:

• a) at least one silicon containing silane compound selected from the group consisting of:
• i) an amino-functional trialkoxysilane with one amino group per molecule;
• ii) a silane having one terminal amino group and one ureido group per molecule;
• iii) a bis-trialkoxysilane;
• and
• iv) any combination thereof, wherein the composition has a combined content of i), ii), iii), and iv) which ranges from 0.02 to 1 g/L, calculated on the basis of the corresponding silanes;
• b) at least two different complex fluorides selected from the group consisting of complex fluorides of titanium, complex fluorides of hafnium, complex fluorides of zirconium, complex fluorides of aluminum, and complex fluorides of boron;
• and
• c) at least one cation selected from cerium, chromium, iron, calcium, cobalt, copper, magnesium, manganese, molybdenum, nickel, niobium, tantalum, yttrium, zinc, tin and other lanthanides, wherein the content of cations or corresponding compound c) ranges from 0.01 to 6 g/L;
• at least one substance d) selected from the group consisting of
• d1) from 0.01 to 10 g/L a silicon-free compound having at least one of an urea or an ureido group;
• d2) from 0.01 to 5 g/L an anion of nitrite or a compound having at least one nitro group;
• d3) from 0.01 to 1 g/L of a compound based on peroxide;
• and
• d4) 0.01 to 12 g/L of a phosphonate;
• e) water;
• f) at least one organic compound based on at least one member selected from the group consisting of acrylic and urethane;
• g) an organic solvent;
• and
• at least one member selected from the group consisting of an alkoxide, a carbonate, a chelate, a surfactant, a biocide and a defoamer.

A process consisting of coating a metallic surface with a coating composition consisting of:

• a) at least one silicon containing silane compound selected from the group consisting of:
• i) an amino-functional trialkoxysilane with one amino group per molecule;
• ii) a silane having one terminal amino group and one ureido group per molecule;
• iii) a bis-trialkoxysilane;
• and
• iv) any combination thereof, wherein the composition has a combined content of i), ii), iii), and iv) which ranges from 0.02 to 1 g/L, calculated on the basis of the corresponding silanes;
• b) at least two different complex fluorides selected from the group consisting of complex fluorides of titanium, complex fluorides of hafnium, complex fluorides of zirconium, complex fluorides of aluminum, and complex fluorides of boron;
• c) at least one cation selected from cerium, chromium, iron, calcium, cobalt, copper, magnesium, manganese, molybdenum, nickel, niobium, tantalum, yttrium, zinc, tin and other lanthanides, wherein the content of cations or corresponding compound c) ranges from 0.01 to 6 g/L;
• at least one substance d) selected from the group consisting of
• d1) from 0.01 to 10 g/L of a silicon-free compound having at least one of an urea or an ureido group;
• and
• d2) from 0.01 to 12 g/L of a phosphonate;
• and
• e) water;
• wherein when manganese is present, it has a content of at least 0.08 g/L, or when both manganese and zinc are present, the manganese has a content higher than the zinc content, and
• wherein the composition has a free fluoride content which ranges from 0.001 to 3 g/L, calculated as F−.