Abstract: A method for manufacturing microcapsules is provided. The microcapsules each include an electrophoretic dispersion liquid containing at least one type of electrophoretic particles in a dispersion medium, and a capsule body made of an organic polymer and containing the electrophoretic dispersion liquid. The method includes forming droplets of the electrophoretic dispersion liquid by dispersing the electrophoretic dispersion liquid in an polar dispersion medium, and forming the capsule bodies by mixing a polymerization initiator and a polymerizable surfactant having a hydrophilic group, a hydrophobic group and a polymerizable group with the polar dispersion medium so as to coat the droplets with the polymerizable surfactant and induce a polymerization reaction to form the organic polymer.

Abstract: An object of the present invention is to provide a production process of a polymer emulsion which can improve the printing stability and ejection stability of an ink composition. The object can be attained by a production process comprising the steps of: mixing water, a monomer, an emulsifier, and a polymerization initiator together to allow emulsion polymerization to proceed; and then adding a monovalent inorganic hydroxide to adjust the resultant polymer emulsion to a desired pH value.