抄録
The particulate film method was investigated for practical particle size measurement. Water filled in a trough was circulated by a pump. Powder was spread on a trembling water surface and was compressed to form a monoparticulate film. The mean particle size perpendicular to the water surface can be determined by measuring the area and packing fraction of the particulate film. The packing fraction here was measured actually from the area occupied by particles in a photomicrograph of the particulate film. Powders of Glass beads, Calcium carbonate, Lycopodium and Mica were first treated with a flotation agent and then were used as the samples. The results agreed well with the particle size measured by the microscopic method. The packing fraction was found about 0.9 in most cases. Thus the packing fraction may be fixed practically at the value of 0.9 and the mean particle size can be determined only from an area of the particulate film.
As a conclusion, the particulate film method was found to provide simple and practical measurement of the particle dimension, especially such as the thickness of thin flake-like materials and the specific surface area of large particles.
