FORGERY-PREVENTIVE PRINTING INK AND FORGERY-PREVENTIVE PRINTED MATTER

摘要

PROBLEM TO BE SOLVED: To provide forgery-preventive printing ink which is free of hazardous heavy metals such as mercury, safe, excellent in durability and stability, bring about a clear change in color depending on a change in temperature and has an easily manufacturable simple composition, and forgery-preventive printed matter printed with the ink which allows a visual authenticity determination in a simple and accurate manner without using a special authenticity determination device and hence difficult to be forged.;SOLUTION: The forgery-preventive printing ink contains a thermochromic metal complex compound having a ligand and a central metal which the ligand coordinates with, and presents different colors resulting from a reversible structural change caused by a change in the environmental temperature to prove authenticity. At least part of the printing substrate requiring forgery-prevention of the forgery-preventive printed matter is printed with the forgery-preventive printing ink.;COPYRIGHT: (C)2008,JPO&INPIT