Abstract: A method of forming a hydrophilic coating on an aluminum surface comprises the steps of:A. etching the aluminum surface;B. treating the etched aluminum surface with an acidic first aqueous solution comprising from about 0.5 to about 3 g/l of active fluoride, from about 2.5 to about 60 g/l of chromate ion (calculated as CrO.sub.3) and from about 2 to about 300 g/l of phosphate ion, so as to form a coating having a weight of at least 150 mg/sq. ft.;C. treating the aluminum surface with an alkaline second solution containing an alkali metal silicate; andD. baking the treated aluminum surface.

Abstract: A composition and method for treating tin-plated ferrous metal surfaces to remove oils and other contaminants in the form of soil thereon, without etching the surface. Particularly, this invention relates to a composition and method for cleaning drawn and ironed tin-plated ferrous metal containers.