To provide printed matter which enables determination of its genuineness through the fluorescent emission of two fluorescent materials in an almost isochromatic state or in a heterochromatic state, depending on different observation conditions, with the use of an ink composition containing a resin composition which gives a fluorescent emission under specified conditions.

A first printing region on the surface of a base is printed in a first ink containing a resin composition which gives an emission in a first luminescent color by a two photon excitation which brings about the excitation of an exciting substance by forming an exciting substance through irradiating a first excitation wavelength range λ1, and through irradiating a second excitation wavelength range λ2 after irradiating the first excitation wavelength range λ1. Next, a second printing region is printed in a second ink containing a fluorescent pigment which gives an emission in a second luminescent color not containing the resin composition giving an emission by the two photon excitation. In this case, the first ink and the second ink are almost isochromatic or heterochromatic, and observed in an almost isochromatic state or a heterochromatic state under a visible light. After irradiating the first excitation wavelength range λ1, the second excitation wavelength range λ2 is also, irradiated. As a result, the first printing region and the second printing region give fluorescent emission in an almost isochromatic state or a heterochromatic state.

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