| 摘要 |
PROBLEM TO BE SOLVED: To provide a method which prevents excessive polymerization, even when carried out in an aqueous system, in coating a fine particle with a high molecular polymer and also suppresses formation of coarse particles of the high molecular polymer and aggregation of fine particles.SOLUTION: In coating a fine particle, e.g. a polydivinylbenzene fine particle, containing a magnetic material with a high molecular polymer, e.g. glycidyl methacrylate, ultrasonic waves of oscillation frequencies of 20 kHz or higher, preferably 40 kHz or higher, are applied so as to produce a fine particle coated with the high molecular polymer. |
