| 摘要 |
PURPOSE:To make it possible for anyone to readily discriminate the genuineness of a card without the need of a professional by coating a base substance, which constitutes a card, with a color coupler and using a pigment, which is adapted for reacting on the color coupler for color development, as ink for use in a stamp so that the genuineness of a card is discriminated on the basis of a color change of the base substance at that portion which is stamped by the stamp. CONSTITUTION:A base substance which constitutes a card 1 adapted for stamping by a stamp 5 is coated with a color coupler (for example, bisphenol A), and a pigment (for example, 3-di-butylamino-6-methyl-7-anilinofluoran) adapted for reacting on the color coupler for color development is used as ink for use in the stamp 5. The genuineness of a card 1 is discriminated on the basis of a color change of the base substance at a portion 3 which is stamped by the stamp 5. As a result, it is possible for anyone to readily discriminate the genuineness of a card without the need of a professional. |
