Method for producing single-hole hollow polymer particles

Abstract

Provided is a method for producing single-hole hollow polymer particles which have an extremely uniform outside diameter and inside diameter, and thus do not require a classifying operation. Further provided are single-hole hollow polymer particles produced by such a method for producing single-hole hollow polymer particles. The invention relates to a method for producing single-hole hollow polymer particles, which includes: preparing a dispersion of swollen particle droplets by mixing a seed particle dispersion obtained by dispersing uncrosslinked polymer-containing seed particles in a water-containing dispersion medium, with a radical polymerizable monomer, an oil-soluble solvent and an oil-soluble polymerization initiator, and causing the radical polymerizable monomer, the oil-soluble solvent and the oil-soluble polymerization initiator to be absorbed in the seed particles; and polymerizing the radical polymerizable monomer in the swollen particle droplets. The relationship between the SP value of a polymer obtained by polymerizing the radical polymerizable monomer (SPp) and the SP value of the oil-soluble solvent (SPs) satisfies formula (1) below: 2.1≦SPp−SPs≦7.0  (1).

Dependencies are inferred from the claim text.