METHOD OF PREPARING PHOSPHATE BINDER Russian patent published in 2000 - IPC

FIELD: chemical technology, more particularly preparation of binding phosphate materials for decorative and protective coatings on concrete, brink, metal or wood. SUBSTANCE: method comprises stirring orthophosphoric acid with aluminium hydroxide at elevated temperature and introducing reducing agent. Orthophosphoric acid having concentration pf 58-65% is first stirred with chromic anhydride and aluminium hydroxide and is then dissolved, and the resulting reaction mixture is thereafter cooled to 80-95 C and paraform is added, and reaction mixture is heated to boiling temperature and maintained for 30 minutes. Paraform is added in stoichiometric ratio with respect to chromic anhydride. EFFECT: simplified method for reducing synthesis time, and more stable composition of the final product. 2 cl, 2 tbl