Patent ID: 7753514

Claim:
An ink composition comprising a monofunctional monomer at a mixing ratio of 50 to 70% by weight, a bifunctional monomer at a mixing ratio of 26.1 to 30% by weight and a multifunctional monomer at a mixing ratio of 1 to 10% by weight, said monofunctional monomer comprising at least N-vinylformamide, wherein the composition has a viscosity of less than 10 mPa·s at 25° C., the composition is solventless and, when deposited on a recording medium and irradiated with ultraviolet light from an ultraviolet light emitting diode, the ink composition is curable in 15 seconds or fewer when the ultraviolet irradiation is carried out at an irradiation intensity of 20 mW/cm 2 .