Patent ID: 8591018

Claim:
An ink set comprising: a water-based ink for ink jet recording; and a treatment liquid, wherein the water-based ink comprises a phosphate-group modified self-dispersing pigment, water, and a water-soluble organic solvent, the treatment liquid comprises an aggregating agent, water, and a water-soluble organic solvent, a dynamic surface tension of the water-based ink, measured under a condition where a life time is 50 ms, is in a range of 35 mN/m to 45 mN/m, a dynamic surface tension of the treatment liquid, measured under a condition where a life time is 50 ms, is in a range of 33 mN/m to 45 mN/m, and a difference in dynamic surface tension between the water-based ink and the treatment liquid is in a range of 0 to 12 mN/m.