To provide an aqueous planographic ink that permits washing of a printing machine and a printing plate with water after printing, can improve global environments and working environments and exhibits excellent high-speed printing aptitude and stain resistance.
The aqueous planographic ink comprises (a) an extender pigment, (b) a pigment, (c) at least one water-soluble resin or a water-dispersible resin selected from among an acrylic resin, a styrene-acrylic resin, a styrene-maleic acid resin and an -olefin-maleic acid resin, (d) a hydroxy group-containing compound and/or an amino group-containing compound, and (e) water, and has a viscosity of 10-200 Pa s at a shear rate of 120 s-1 at 25C as measured by a cone plate type rotational viscometer, where the extender pigment (a) accounts for 0.1-15 wt.% of the whole amount.
UTSUGI MASAKI
AKIMOTO TAKASHI
