AQUEOUS INK SET, INK JET RECORDING METHOD AND INK JET RECORDING APPARATUS

摘要

An aqueous ink set for ink jet including a combination of a first ink and a second ink. The first ink contains a self-dispersible pigment to a particle surface of which a functional group containing a phosphonic acid group is bonded, wherein the redispersion viscosity of the first ink is 5 mPa·s or less. The second ink contains an anionic dye, a lithium ion and a sodium ion, wherein the total concentration of the lithium ion and the sodium ion in the second ink is 0.050 mol/L or more, and the proportion of the concentration of the lithium ion in the total concentration of the lithium ion and the sodium ion in the second ink is 45% or more and 85% or less.

主权项

1. An aqueous ink set for ink jet comprising a combination of a first ink and a second ink,
wherein the first ink contains a self-dispersible pigment to a particle surface of which a functional group containing a phosphonic acid group is bonded, and a redispersion viscosity of the first ink as measured according to the following procedure is 5 mPa·s or less, measurement of the redispersion viscosity being such that after 1.5 g of the first ink is stored for 15 hours under a temperature of 30° C. and a relative humidity of 10%, the first ink is added thereto in an amount of the thus-reduced mass followed by additional storing for 2 hours to thereby measure the viscosity of the resultant, wherein the second ink contains an anionic dye, a lithium ion and a sodium ion, and a total concentration of the lithium ion and the sodium ion in the second ink is 0.050 mol/L or more, and wherein a proportion of a concentration of the lithium ion in the total concentration of the lithium ion and the sodium ion in the second ink is 45% or more and 85% or less.