Abstract: An aqueous liquid surface treatment composition having a pH value not more than 6.5 and containing phosphoric acid ions, condensed phosphoric acid ions, an oxidizing agent, and a water-soluble polymer consisting, except for end groups, of polymer units expressed by formula (I), in a weight ratio of 0.1 to 30:0.1 to 10:0.1 to 10:0.1 to 20 respectively, when brought into contact with an aluminiferous metal surface, rapidly forms on the surface a conversion coating that has good corrosion resistance and adhesion to subsequently applied organic coatings such as paint and is less easily damaged by mechanical stresses than prior art conversion coatings.
Abstract: An aqueous liquid chromate free primary composition for forming a protective coating on metals, particularly aluminum, is made by reacting cobalt(II) cations, carboxylate anions, at least one other type of coordinate complexing agent for cobalt(III) cations, and an oxidizing agent in an aqueous solution in which the molar ratio of carboxylate anions to cobalt(II) cations is from 0.10 to 6.8 and the aqueous solution contains no more than 1% of each of ammonia, ammonium ions, and nitrite ions. The primary layer formed by this or any other composition that forms a coating containing metal atoms and oxygen atoms on a metal substrate is advantageously sealed by further treatment with an aqueous solution of sodium ammonium decavanadate, optionally after an intermediate step of immersing in water for a few minutes between the primary treatment and the sealing treatment.
Abstract: Drying into place a covering of an aqueous solution of nickel and/or cobaltous sulfate and/or phosphate salts on a zinc or zinc alloy surface improves at least one of the blackening resistance and corrosion resistance after subsequent chromating treatment and the corrosion resistance and paint adherence after subsequent chromating treatment and painting.
Abstract: Esters and mixtures of esters of polyhydric alcohols, e.g., of pentaerythritol, in which at least 22 number percent of the acyl groups in the esters are either branched or contain no more than six carbon atoms, are effective lubricants and/or lubricant base stocks for chlorine-free fluorocarbon refrigerant heat transfer fluids, particularly for chlorine-free heat transfer fluids such as Refrigerant 134a (1,1,1,2-tetrafluoroethane).