Wet milling process of the organic solid matter, an aqueous dispersion of particulate organic solid material, and recording material coated with an aqueous dispersion of particulate organic solid material

摘要

PURPOSE:To rapidly and uniformly pulverize an org. solid material by adding polyvinyl alcohol (PVC) which is of a specific value in the surface tension of the aq. soln. and of a specific value in the degree of polymn. into an aq. dispersion contg. said material and subjecting the dispersion to wet grinding with a sand mill. CONSTITUTION:The PVA which has =63 dyne/cm surface tension of the 0.1% aq. soln. and =500 of polymn. is added into the aq. dispersion of the org. solid material at 0.2-10pts.wt. per 100pts.wt. org. solid material. The aq. dispersion of this org. solid material is subjected to the wet pulverization by the sand mill. The org. solid material includes org. pigments, org. dyes, org. color develop ing agents, org. thermoplastic materials, etc. The pulverization efficiency is extremely improved if the PVA polymer having an R-S-group (R denotes an alkyl group of 8-20C) at one terminal is used in combination with the above- mentioned PVA.