Microscopic particle decentralized solution having microscopic particles with different diameters are decentralized, wherein: the microscopic particle decentralized solution has two peaks in a granularity distribution, at a large diameter and a small diameter; and microscopic particle mixtures satisfying the following relationships are decentralized in the solution; R>r and n>3.84.times.(R/r).sup.3.times.N, where R is a large particle diameter, r is a small particle diameter, N is the number of large particles, and n is the number of small particle.