PRODUCTION OF POLYMER FINE PARTICLE

摘要

PURPOSE:To provide polymer fine particles prevented from secondary aggregation in its drying. CONSTITUTION:Ultrafine particles having a diameter <=1/10 times that of the mean diameter of fine particles consisting of polyurethane or polyurea resin are made to adhere to the fine particles. The weight ratio of the ultrafine particles to the fine particles satisfies a specific relationship. With this method, the secondary aggregation of the fine particles in the drying process can be suppressed to a minimum, improving disaggregation efficiency. Besides, the fine particles' yield is improved with the mean particle diameter virtually the same before and after drying, simplifying the fine particles' production.