METHOD FOR PHOSPHATING METALLIC SURFACE Russian patent published in 2003 - IPC

FIELD: chemical treatment of metal surface. SUBSTANCE: invention relates to compositions used for treatment of metal surface based on iron and zinc- -plated steel. Method involves treatment of surface with solution containing the following components, g/l: Zn²⁺, 0.8-4.3; Mn²⁺, 0.4-2.4; P₂O₅, 4.1-18.5; NO₃, 1.1-5.5; hydroxylamine sulfate, 2.6- 13.0; water, the balance at temperature 35-40 C and free acidity of the solution 0.7-2.3 point. Invention provides: 1) high corrosion resistance of phosphate coating in complex with paint and varnish covers; 2) adhesion of paint and varnish covers in common with phosphating coating is 1 score; 3) economy of energy resources; 4) improved conditions in manufacture. Proposed compositions are useful for treatment of articles exhibiting complex configuration of surface, for example, car baskets that is carried out before application of paint and varnish covers. EFFECT: improved phosphating method. 4 ex