Particle for display medium and information display panel utilizing the same

A method of producing particles for display media constituting the display media, used for an information display panel, in which the display media are sealed between two substrates, at least one of two substrates being transparent, and, in which the display media, to which an electrostatic field is applied, are made to move so as to display information, comprising the steps of:

• preparing particle raw materials including monomers, which include (acrylic or methacrylic) resin-hydrocarbon resin copolymer, in which a part of or all of the monomers are multifunctional polymerization reactive groups in one molecule;
• suspending the prepared particle raw materials in a suspended solvent including at least one or more su-face activators;
• and
• polymerizing the particle raw materials so as to obtain substantially spherical particles;
• in which:
• the particle raw materials are suspended in the suspended solvent to be an oil spot having a diameter larger than a predetermined oil spot diameter;
• a material having an effect of starting or promoting the polymerization by dissolving it, under such a condition that ten hours half period temperature is not more than 75° C., is added in the suspended solvent;
• a step of suspending the particle raw materials to a predetermined oil spot diameter and a step of dispersing the material are performed simultaneously;
• and
• a polymerization is performed so as to obtain particles for display media having an even minute irregularities on the surface of the particles.