CHILD PARTICLE OF COMPOSITE PARTICLE FOR DISPLAY MEDIUM AND PRODUCTION METHOD OF THE CHILD PARTICLE, COMPOSITE PARTICLE FOR DISPLAY MEDIUM USING THE CHILD PARTICLE, AND INFORMATION DISPLAY PANEL USING THE COMPOSITE PARTICLE FOR DISPLAY MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide child particles constituting composite particles for a display medium excellent in charging characteristics.SOLUTION: The present invention relates to particles for a display medium, for constituting a display medium to be used for such an information display panel that the display medium is sealed between two substrates at least one of which is transparent and that information is displayed by moving the display medium. In particular, the particles for the display medium are composite particles for a display medium, comprising mother particles and child particles adhering to the surfaces of the mother particles. The child particles are produced by an emulsion polymerization method or a dispersion polymerization method. In the production process, the conductivity of a final cleaning liquid differs by 2 s/cm or less from the conductivity of a solvent. The child particles after being dried shows a hydrophobicity degree, by a water-methanol wetting test, of 20% or more in terms of methanol concentration.