METHOD OF PREPARING ANTICORROSIVE PIGMENT BASED ON MODIFIED ZINC PHOSPHATE Russian patent published in 2001 - IPC

FIELD: preparation of zinc phosphate base anticorrosive pigments used in primers, compositions, paintwork materials for protection of various metals and alloys from corrosion. SUBSTANCE: zinc oxide is hydrated in water at 70-90 C, then treated with phosphoric acid in excessive amount more than stoichiometrically essential to form zinc phosphate followed by stirring and neutralization with suspension of highly dispersed calcium and strontium carbonates at weight ratio thereof 1: (1-10) under stirring conditions to adjust pH to 5.5-7.5 with calcium and strontium phosphates precipitated on surface of the resulting zinc phosphate during stirring operation in total amount of 4-11 wt.% calculated for CaO and SrO of the final product, suspension is then filtered and paste is dried. Modified zinc phosphate base coatings have improved protective properties. EFFECT: more efficient preparation method. 13 ex, 1 tbl