Patent ID: 8142007

Claim:
An ink set comprising: (1) a white ink composition A comprising at least a colorant and one or more photopolymerization initiators, including at least a first photopolymerization initiator, said first photopolymerization initiator comprising at least 60% by weight of a total amount of the one or more photopolymerization initiators of the white ink composition A; and (2) a transparent ink composition B comprising at least a polymerizable compound, a polymerization accelerator and one or more photopolymerization initiators, including at least a second photopolymerization initiator, said second photopolymerization initiator comprising at least 60% by weight of the one or more photopolymerization initiators of the transparent ink composition B; wherein the first photopolymerization initiator is more effective than the second photopolymerization initiator in promoting curing of an interior of a photocurable coating formed by ejecting white ink composition A onto a recording medium and then ejecting transparent ink composition B onto white ink composition A, said first photopolymerization initiator decomposing upon absorption of ultraviolet light to form residues that do not absorb ultraviolet light, and wherein the second photopolymerization initiator is more effective than the first photopolymerization initiator in curing a surface of the photocurable coating, said second photopolymerization initiator being capable of suppressing polymerization inhibition due to permeation of oxygen.