| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an ink material which enables printing of a printed matter having high security properties. <P>SOLUTION: The ink material has a base (1), a first fluorescent ink layer (L1) which is an ink layer provided on one side of the base and contains a fluorescent color material (3) emitting light of a first wavelength under irradiation with excitation light and keeping up afterglow over a first time after the end of irradiation with the excitation light and a second fluorescent ink layer (L2) which is an ink layer provided on the above one side of the base and contains a phosphor (4) emitting light of a second wavelength under irradiation with the excitation light and keeping up the afterglow over a second time longer than the first time after the end of irradiation with the excitation light. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
