Description of products: This product is a white powder, harmless, smelliless, insoluble in water, organic acids and week in organic acids, but slightly soluble in alkali. It dissolves completely in bliling concentrated acid, hydrofluoric acid and saturated solvent of potassium bicarbonate. It has good covering strength, excellent pigment properties, high achromacity and low oil absorption.S.G.3.90; Bielectricity constant: 48; Refrangibility: 2.52; Hardness: 5.0-6.0.