摘要 |
The invention provides surface-modified carbon black which exhibits excellent dispersibility in silicone oil which is a nonpolar medium; and dispersions of the surface-modified carbon black. The surface-modified carbon black is characterized by chemical bonding of an isocyanate compound having isocyanate groups at both ends which compound is bound to a functional group on the surface of carbon black by a urethane linkage to a reactive silicone polymer, while the dispersions are characterized by being produced by dissolving an isocyanate compound having isocyanate groups at both ends in a solvent, adding carbon black to the solution to bind an isocyanate group to the surface of carbon black particles by a urethane linkage, removing unreacted isocyanate compound, dispersing the resulting system in silicone oil, adding a reactive silicone polymer to the dispersion, and subjecting the resulting dispersion to mixing and defoaming. |