Patent ID: 8133936

Claim:
An ink-jet ink substantially free of water and volatile organic solvents comprising at least one monofunctional (meth)acrylate monomer; at least one monofunctional N-vinyl amide monomer, wherein said at least one monofunctional N-vinyl amide monomer is selected from the group consisting of N-vinyl caprolactam (NVC) and N-vinyl pyrrolidone (NVP); at least one radical photoinitiator; at least one colouring agent; wherein the ink has a viscosity of less than 100 mPas at 25° C., and wherein the molar ratio of the at least one monofunctional (meth)acrylate monomer to the at least one monofunctional N-vinyl amide monomer is from 1.1 to 2.0, and further wherein said ink-jet ink has a higher cure speed than a cure speed of an ink-jet ink which comprises only one of the at least one monofunctional (meth)acrylate monomer and the at least one monofunctional N-vinyl amide monomer.