CARBON BLACK PIGMENT FOR ELECTRONIC PAPER, DISPERSION OF THE PIGMENT, AND PROCESS FOR PRODUCTION OF THE PIGMENT

摘要

Disclosed are: a surface-modified carbon black pigment, which is suitable as a black-color microparticle for use in an electronic paper; a dispersion of the carbon black pigment in a silicone oil; and a process for production of the carbon black pigment. The carbon black pigment for an electronic paper comprises a surface-modified carbon black, in which a diphenylmethane group urethane-bound to a carbon black particle through a functional group on the surface of the carbon black particle is bound to a polysiloxane group. The carbon black dispersion for an electronic paper comprises 1 to 20% by weight of the carbon black pigment dispersed in a silicone oil. The process for production of the carbon black pigment comprises the steps of: reacting a functional group on the surface of a carbon black particle with a diphenyl compound having an isocyanate group at its both termini in a non-reactive organic solvent to cause the attachment the diphenylmethane group to the surface of the carbon black particle through an urethane bond; and binding a polysiloxane to the resulting compound in a silicone oil.