An ink for ink jet printers according to claim 1 or 2, wherein the pigment is an organic pigment and/or carbon black, and the silicone graft polymer is dispersed in the organic solvent in the form of particles having a particle diameter of 0.01-0.3 ??m in such a state as the silicone graft polymer being adsorbed to at least a part of the outer surface of the organic pigment and/or carbon black.