Patent ID: 7915326

Claim:
A printing ink composition which is used in a printing ink, the printing ink composition comprising composite particles (A), wherein each of the composite particles (A) comprises: a solid polymer particle (B) formed of a wax or a mixture of a resin and the wax and insoluble in the printing ink; and inorganic particles (C) having an average particle diameter of 5 to 1000 nm; wherein the composite particles (A) have a volume-average particle diameter in a range of 2 to 8 μm in which a volume content of solid polymer particles having a particle diameter of exceeding 10 μm is 5 vol. % or less; and wherein each of the composite particles (A) is formed to cover substantially the surfaces of the solid polymer particle (B) with the inorganic microparticles (C); and wherein said wax has a melting point of 125° C. or more and a needle penetration degree of 1.0 or less at 25° C.