INFORMATION RECORDING MEDIUM, PRINTED MATTER AND REPRODUCING APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide an information recording medium excellent in forgery preventing properties, printed matter capable of giving the excellent forgery preventing properties to the information recording medium and a reproducing apparatus which can be used for decision on the authenticity of the information recording medium. SOLUTION: The information recording medium 10 has a base 11 for recording information and printed patterns 12, 21 and 22 provided on the base 11. The printed patterns 12, 21 and 22 contain a first coloring material causing a color change under the action of an electromagnetic field and a second coloring material causing no color change under the action.