Low the crystal Characteristic silica and the production mannered null thickness

摘要

PROBLEM TO BE SOLVED: To obtain a scaly low crystalline silica harmless to a human body, excellent in reactivity on the surface useful as a filler for cosmetic, antiperspirant, pack agent, coating material or resin and for various carriers and to provide a method for producing the silica. ;SOLUTION: This scaly low crystalline silica has 0.001-1 μm thickness, 10 ratio (aspect ratio) of the longest length of the scaly plate to the thickness, ≥3 ratio of the shortest length of the scaly plate to the thickness, 10% measured value of crystal type free silicic acid by X-ray diffraction a nalysis and silanol group absorptions at 3,600-3,700 and 3,400-3,500 cm^-1 of IR spectrum. This method for producing the silica comprises dealkalizing an aqueous solution of a silicic acid to give a silica sol and subjecting the sol to hydrothermal treatment.;COPYRIGHT: (C)1999,JPO