METHOD FOR PREPARING ULTRAFINE PARTICLE OF ORGANIC COMPOUND

PURPOSE:To obtain ultrafine particles of an org. compound, especially, water-insoluble medicine, by evaporating the org. compound under heating in inert gas within a vacuum container and coagulating fine particles generated by collision on a cooled recovery means. CONSTITUTION:An org. compound (containing a high-molecular compound) having vapor pressure of a definite value or more is put in a heating apparatus 2 and, after a vacuum container 1 is brought to a predetermined vacuum degree, inert gas is introduced into the container 1 to adjust the pressure thereof to a definite value and the heating of the org. compound is started. The molecules of the org. compound evaporated by heating are scattered and collide with each other to be formed into ultrafine partcles which are, in turn, coagulated on a coolled aluminum foil 7 to be accumulated thereon. As mentioned above, by regulating the pressure of the inert gas, ultrafine particles with a particle size of about 500Angstrom -4mum can be obtained. If the obtained fine particles are prepared from water-insoluble medicine, the stable aqueous dispersion thereof can be obtained and, therefore, an injection liquid can be obtained. Further, said particles can be expected as the material of an org. semiconductor or a sensor.