Patent ID: 7670442

Claim:
A liquid concentrate composition of matter that when mixed with 9 times its own mass of water is a solution that forms a phosphate conversion coating on a solid metal substrate with which it is contacted, said concentrate composition comprising water and: (A) a component of dissolved phosphate anions in an amount sufficient to form the phosphate conversion coating on the substrate from a working composition made by diluting the concentrate composition with water only; (B) a component of sufficient dissolved acid to give the concentrate composition itself and a working composition made by diluting the concentrate composition with water only, an acidic pH value of less than 3 and at least 20 points total acid; (C) a component of dispersed aromatic carboxylic acid in an amount sufficient for the working composition to protect the phosphated substrate against flash rusting; and (D) a component of viscosity increasing agent that is not part of any of components (A) through (C) as recited immediately above.