SURFACE-TREATED CALCIUM CARBONATE POWDER, ITS PRODUCTION AND RESIN COMPOSITION COMPOUNDED THEREWITH

摘要

PROBLEM TO BE SOLVED: To obtain the subject powder capable of imparting moisture-curable one-pack resins with excellent thixotropy, slump resistance and storage stability by surface treatment of calcium carbonate powder so that its sedimentation degree determined by a specific method fall within a specified range. ;SOLUTION: This surface-treated calcium carbonate powder has such a requirement that its sedimentation degree determined by the method described below is ≤10 mL: 70 mL of water at 25°C is put into a stopper-bearing measuring cylinder 100 mL in volume followed by adding 7 g of calcium carbonate powder as sample to the water; the resulting mixture is vibrated for 15 min using a shaker 4 cm in amplitude and 320 cycles/min in frequency; after vibration, the mixture is left at rest for 10 min, and the apparent volume of the resulting sediment is read using the scale on the measuring cylinder and defined as sedimentation degree. The surface treatment agent is pref. a fatty acid ester which accounts for pref. ≥70 wt.% of the whole surface treatment agent. The calcium carbonate to be used is pref. ≥8 m²/g in BET specific surface area.;COPYRIGHT: (C)1999,JPO