PT-522 Zinc Chromate Primer -- TT-P-1757 TYI CLASS C & N is a general purpose, rust inhibitive, alkyd primer. It is intended for use over metals that are bare, scuffed, sanded, lightly rusted, abrasive blast and previously painted surfaces while showing excellent anti-corrosion properties. The primer chemically etches into the surface to provide exceptional adhesion and durability. Also, moisture in the air causes the zinc chromate to react with the metal surface, and it forms a passive film that prevents corrosion. Although this primer is intended for metals, it may be applied to wood, composite and concrete surfaces. PT-522 is not resistant to all solvents, i.e. MEK and Acetone.