A preparation of spherical calcium carbonate and application to paper

Silica is generally used for ink-jet paper as a coating pigment for high print quality. As a substitute of expensive silica, calcium carbonate having a crystal form of vaterite was examined in terms of the preparation method for high purity and surface wetting behavior of its coated paper. Pure vaterite synthesis was successfully achieved by the modified interfacial reaction method, i.e., at a temperature of 25 degrees C of all the reacting liquids and high shear rate during mixture. Spherical vaterite aggregates developed so is around 1 mu m diameter and consists of primary particle less than 100 nm diameter. As for vaterite-coated paper, comparatively adequate surface wetting behavior for ink-jet printing was obtained. Contact angle between a water droplet and a paper surface decreased with time by absorption for vaterite while it decreased by lateral spreading for silica. These phenomena suggest that vaterite is potential to absorb water very quickly. Thus, the potential of vaterite as a coating pigment was suggested.