Synthesis, Acid and Base Resistance of Various Copper Phosphate Pigments by the Substitution with Lanthanum

摘要

Transition metal phosphates are used as inorganic pigments, however these materials have a weak point for acid or base resistance. Because lanthanum phosphate is insoluble in acidic or basic solution, the addition of lanthanum was tried to improve the acid or base resistance of copper phosphate pigment. Various cooper – lanthanum phosphates were synthesized in wet (H3PO4, Cu(NO3)2, La(NO3)3) or dry (H3PO4, CuCO3●Cu(OH)2●H2O, La2O3) processes. The additional effects of lanthanum were studied on the chemical composition, particle shape and size distribution, specific surface area, color, acid and base resistance of the precipitates and their thermal products.