| abstract |
The present invention addresses the problem of obtaining an ink set for forming images of excellent quality with favorable dot expandability of a printing unit, even in the presence of an acid atmosphere produced around an ink nozzle, etc. when a volatile acid is used in a pretreatment solution. Provided as a solution is an ink set comprising: a first ink composition that contains 1.0 mass% or more, in the ink composition, of an alkali-soluble resin or a crosslinked product thereof that has an acid value of 200 mgKOH/g or higher, along with a white pigment, and furthermore contains water; and a second ink composition that is for further printing onto a printing layer made of the first inkjet printing ink composition, that contains 1.0 mass% or more, in the ink composition, of an alkali-soluble resin or a crosslinked product thereof that has an acid value of 200 mgKOH/g or higher, along with a color pigment, and that furthermore contains an amphoteric surfactant, a water-dispersible resin, and water. |