| abstract |
A process for forming a chromium/silica/phosphate protective conversion coating on a metal surface is improved by pretreating the surface with a composition comprising at least one of (i) H2TiF6, (ii) H2SiF6, and (iii) a derivative of poly{alkenylphenol} before applying the conversion coating. The process of the invention results in a protective base coating having superior adhesion to paint at a relatively high coating weight which is desirable for improved corrosion resistance. This process is especially useful in forming such protective conversion coatings on continuous cast aluminum surfaces. |