Patent ID: 7621628

Claim:
A water-based ink set for ink-jet recording comprising a magenta ink and a red ink, wherein dynamic surface tensions of the magenta ink and the red ink as determined by a maximum bubble pressure method at a measurement temperature of 25° C. satisfy the following inequalities (I M ), (II M ), (III M ) and (IV M ) σ 30M ≦about 49 mN/m (I M ) σ 30M +σ 30R ≦about 100 mN/m (II M ) wherein σ 30M is dynamic surface tension of the magenta ink at a lifetime of 30 ms and σ 30R is the dynamic surface tension of the red ink at a lifetime of 30 ms, σ 1000R ≧about 36 mN/m (III M ) σ 1000M +σ 10000R ≧about 70 mN/m (IV M ) wherein σ 1000M is dynamic surface tension of the magenta ink at a lifetime of 1,000 ms and σ 1000R is the dynamic surface tension of the red ink at a lifetime of 1,000 ms.