Ultra-dry calcium carbonate particles, a method for drying calcium
carbonate particles and also the use of the resulting dried calcium
carbonate as a flow property regulating agent in sealing compounds or
adhesive compositions. The calcium carbonate particles are dried with
microwaves. The drying can take place in a continuous belt apparatus, a
batch treatment apparatus or a rotary-tube apparatus, and calcium
carbonate particles having a degree of dryness of 0 to 0.1% H.sub.2O can
be obtained.