In Examples 1 and 2 wherein the maximum particle size of the starting material was no greater than 63 μm and {TAIL ~ the mean particle size} of the talc was at least 5 μm as shown in Table 1, no cell breakage was observed and the void volume exceeded {HEAD ~ 30%} 
In Examples 1 and 2 wherein the maximum particle size of the starting material was no greater than 63 μm and { TAIL ~ the mean particle size } of the talc was at least 5 μm as shown in Table 1 , no cell breakage was observed and the void volume exceeded { HEAD ~ 30 % }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD