| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain a novel thread having a truth or falsehood determining function which has not been in a prior art, and to obtain a forgery preventive sheet using the same. <P>SOLUTION: The thread having the truth or falsehood determining function which has not been in the prior art in combination with one type of a metamerism of a visible light ray range and an infrared ray range and a multilayer pearlescent film (1) is obtained. A print layer (3a) of a design, a character, etc. having a performance of absorbing an infrared ray and a print layer (3b) of a design, a character, etc. having a performance of transmitting the infrared ray are, for example, provided on one side surface of the multilayer pearlescent film (1) having a performance of transmitting both a visible light ray and an infrared ray. The print layer (3a) of the design, the character, etc. having the performance of absorbing the infrared ray and the print layer (3b) of the design, the character, etc. having the performance of transmitting the infrared ray of the thread are observed in an isochromatic manner by a normal light, and a spectral reflectivity in the infrared ray range of each of the layers is different. <P>COPYRIGHT: (C)2004,JPO</p> |
