Calcium silicate and process for producing same

Abstract

Globular secondary particles of wollastonite group calcium silicate crystals represented by the formula lCaO.mSiO.sub.2.nH.sub.2 O wherein 1.ltoreq.l.ltoreq.6, 1.ltoreq.m.ltoreq.6 and 0.ltoreq.n.ltoreq.1, characterized in that the particles comprise hollow globular secondary particles of the wollastonite group calcium silicate crystals, the globular secondary particles having an average spontaneous sedimentation height of at least 800 ml, an outside diameter of 5 to 110 .mu.m, an average apparent density of 0.04 to 0.09 g/cm.sup.3 and an average shell density defined by the equation Y=0.0033X+B wherein Y is the average shell density, X is the average diameter of the particles, B is a constant, 15 .mu.m.ltoreq.X.ltoreq.40 .mu.m and 0.ltoreq.B.ltoreq.0.115.

Dependencies are inferred from the claim text.