Abstract: This invention comprises an acidic aqueous solution for treating metal substrates to improve the adhesion bonding and corrosion protection of the metal surface which comprises effective amounts of water soluble trivalent chromium compounds, fluorozirconates, effective amounts of at least one corrosion inhibitors such as benzotriazole, fluorometallic compounds, zinc compounds, thickeners, surfactants, and at least about 0.001 mole per liter of the acidic solution of a polyhydroxy and/or carboxylic compound as a stabilizing agent for the aqueous solution.

Abstract: Pretreated aluminum and aluminum alloys and the process and composition for pretreating said aluminum and its alloys to provide a coating with color recognition for identification purposes and to improved the corrosion-resistance, electrical conductivity, and adhesion properties which comprises pretreating said aluminum and its alloys with an effective amount of an acidic aqueous solution having a pH ranging from about 2.5 to 5.5 comprising water soluble trivalent chromium compounds, alkali metal hexafluorozirconates, divalent zinc compounds, alkali metal fluoro-compounds, and effective amounts of water soluble thickeners, surfactants or wetting agents.

Abstract: Aqueous compositions for post-treating metal coated substrates such as cadmium-plated steel, and zinc-nickel coated substrates and the process for using said compositions to provide a color recognizable coating and to improve the corrosion-resistance, abrasion, electrical, and adhesion properties of the coating. The post-treatment composition comprises an acidic aqueous solution having a pH ranging from about 2.5 to 5.5 and contains effective amounts of trivalent chromium compounds, alkali metal hexafluorozirconates, at least one divalent zinc compound, alkali metal fluoro-compounds, and effective amounts of water soluble thickeners, wetting agents or surfactants.