Zinc phosphate coating compositions containing oxime accelerators

An aqueous acidic composition for forming a zinc phosphate coating on a metal substrate comprising about 0.8 to 1.2 g/l of zinc ion, about 12 to 14 g/l of phosphate ion, about 0.25 to 1.0 g/l of fluoride ion, about 0.8 to 1.0 g/l of manganese ion, about 0.3 to 0.8 g/l of nickel ion, about 2 to 5 g/l of nitrate ion, and as accelerators about 0.3 g/l of sodium nitrobenzene sulfonate, and about 1 to 5 g/l of acetaldehyde oxime.

An aqueous acidic concentrate comprising about 10 to 100 g/l of zinc ion, about 100 to 400 g/l of phosphate ion, and as an accelerator, about 10 to 400 g/l of an oxime.

The aqueous acidic concentrate as defined in claim further comprising about 2 to 30 g/l fluoride ion.

The aqueous acidic concentrate as defined in claim further comprising about 4 to 40 g/l manganese ion.

A process for forming a zinc phosphate coating on a metal substrate comprising contacting the metal with an aqueous acidic zinc phosphate composition comprising about 0.4 to 3.0 grams per liter (g/l) of zinc ion, about 5 to 20 g/l phosphate ion, and as an accelerator, about 0.5 to 20 g/l of an oxime.

A metal substrate containing from 1.0 to 6.0 grams per square meter (g/m.sup.2) of a zinc phosphate conversion coating applied by contacting the metal with an aqueous acidic zinc phosphate composition comprising about 0.4 to 3.0 grams per liter (g/l) of zinc ion, about 5 to 20 g/l phosphate ion, and as an accelerator, about 0.5 to 20 g/l of an oxime.