Patent ID: 8623405

Claim:
A method of producing a composition having a median diameter of not more than 1 μm, and comprising (i) a poorly water soluble substance, (ii) polyvinylpyrrolidone or vinylpyrrolidone-vinyl acetate copolymer and (iii) an auxiliary dispersion stabilizer, the method comprising: pulverizing (i) a poorly water soluble substance, (ii) polyvinylpyrrolidone or vinylpyrrolidone-vinyl acetate copolymer and (iii) an auxiliary dispersion stabilizer in a liquid using a high pressure homogenizer, wherein when the poorly water soluble substance has a melting point of not less than 140° C., the temperature of the composition just before flowing in the pulverization portion during operation of the high-pressure homogenizer is lower by not less than 100° C. than the melting point of the poorly water soluble substance, and wherein when the poorly water soluble substance has a melting point of less than 140° C., the temperature of the composition just before flowing in the pulverization portion during operation of the high-pressure homogenizer is not more than 40° C.