Patent ID: 8252734

Claim:
A conversion coating comprising potassium, phosphorus, nitrogen, silicon, and one or more non-alkaline metals, wherein said conversion coating is produced by a process comprising the steps of: 1) forming a first aqueous solution of a silicate, potassium hydroxide, and ammonium hydroxide; 2) forming a second aqueous solution by the steps of: a) forming a solution of water with phosphoric acid; b) thereafter adding ammonium hydroxide slowly to the solution of step a) over a period of at least 10 minutes; c) thereafter adding an alkali metal hydroxide in water to the solution produced by step b); d) thereafter adding ammonium hydroxide to the solution produced by step c) to bring the pH to 10-11; e) thereafter adding potassium hydroxide to the solution produced by step d) to bring the pH to 14; and f) adding one or more non-alkaline metal salts to the solution produced by step e); and 3) combining said first solution with said second solution in equal volumes to form a final solution, wherein said final solution forms a conversion coating on a surface when applied to the surface without the use of applied external electromotive force, and wherein said conversion coating contains potassium, phosphorus, nitrogen, silicon, and one or more non-alkali metals.