| abstract |
The purpose of the present invention is to provide an ink for active energy ray-curing planographic printing, said ink exhibiting satisfactory adhesiveness on plastic film and not losing adhesion performance even during hot water treatment. The present invention provides a printing ink containing (a) urethane (meth)acrylate and (c) another polymerizable monomer, the printing ink characterized in that an ink tank value is 5.0 to 18.0 inclusive, viscosity (C) at a rotational speed of 20 rpm and viscosity (B) at a rotational speed of 50 rpm as measured by a cone-plate-type rotating viscometer, both at 35°C, are both 5 to 100 Pa•s inclusive, and the viscosity ratio (B)/(C) is 0.60 to 1.00 inclusive. |