Security mark, authenticationg method therefor, authentication device and manufacturing method as well as security mark ink and manufacturing method therefor

Abstract

As a technique capable of achieving higher security performance in methods for authenticating security marks that use a photochromic compound, provided is an authentication method that comprises: a process for irradiating excitation light on a security mark containing a photochromic compound; a process for acquiring first security information relating to temporal changes of the absorption spectrum and / or the reflection spectrum of the security mark after irradiation of the excitation light; and a process for comparing the acquired first security information with previously acquired first security information on said security mark. In said authentication method, the security mark preferably contains two or more photochromic compounds for which the coloring and / or the rate of decoloring after coloring as a result of a photochromic reaction differ.

Description

technical field [0001] The present invention relates to a security mark and an authentication method thereof, an authentication device and a manufacturing method, and an ink for a security mark and a manufacturing method thereof. More specifically, it relates to an authentication method of a security mark using a photochromic compound, and the like. Background technique [0002] As photochromic compounds exhibiting photochromic properties, there are known diarylethene-based (Patent Document 1), spiropyran-based (Patent Document 2), hexaarylbiimidazole-based (Non-Patent Document 1) and even A compound of nitrobenzene series (Non-Patent Document 2). The so-called "photochromism" is also known as "photochromism", "photochromy", "photointerchange (photoreversible discoloration: phototropy)", which refers to the state of a certain substance in solid or solution A phenomenon in which the color changes when exposed to light of a specific wavelength (ultraviolet or visible light),...

AI Technical Summary

Problems solved by technology

Regarding this security ink, when ultraviolet light or the like is irradiated with respect to the security ink layer formed by coating or printing, the photochromic compound will be colored, and the security marks such as characters and graphics that are coated or printed will change. It can be recognized visually. If the irradiation of ultraviolet light or the like is stopped, the color of the photochromic compound will disappear and the safety mark cannot be recognized visually.

In addition, in Patent Document 7, there is no description of compounding two or more compounds having different photochromic properties in the security ink.

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