Method for producing organic material microparticles, and method for modifying organic material microparticles

Abstract

Provided are a method for producing organic material microparticles and a method for modifying organic material microparticles, whereby it becomes possible to improve the crystallinity of organic material microparticles or achieve the crystal transformation of the organic material microparticles while preventing the growth of the organic material microparticles in a solvent. A surfactant is added to a solvent that is capable of partially dissolving organic material microparticles, and then the organic material microparticles are reacted with the solvent. In this manner, it becomes possible to improve the degree of crystallization of the organic material microparticles or achieve the crystal transformation of the organic material microparticles without substantially altering the particle diameters of the organic material microparticles.

1 . A method for modifying an organic material microparticle, wherein the method is to modify an organic material microparticle without substantially changing a particle diameter of the organic material microparticle;
 the method comprises a step in which a particle property control solution having a surfactant dissolved in a solvent which has a partial dissolvability to the organic material microparticle is made to act to the organic material microparticle; and   by conducting this step, a degree of crystallinity of the organic material microparticle is enhanced so as to modify the organic material microparticle such that the degree of crystallinity thereof may be matched with a prescribed intended condition.   
     
     
         2 . A method for modifying an organic material microparticle, wherein the method is to modify an organic material microparticle without substantially changing a particle diameter of the organic material microparticle;
 the method comprises a step in which a particle property control solution having a surfactant dissolved in a solvent which has a partial dissolvability to the organic material microparticle is made to act to the organic material microparticle;   by conducting this step, a crystal type of the organic material microparticle is changed so as to modify the organic material microparticle in such a way that the crystal type thereof may be matched with a prescribed intended condition.   
     
     
         3 . The method for modifying the organic material microparticle according to  claim 1 , wherein a rate of change in the particle diameter of the organic material microparticle measured before and after the treatment in the step (after treatment in the step (A)/before treatment in the step (B)) is in a range of 1 to 4. 
     
     
         4 . The method for modifying the organic material microparticle according to  claim 1 , wherein the organic material microparticle before the treatment in the step contains an amorphous portion at least in part thereof.