TEMPERATURE HYSTERESIS INDICATOR

摘要

PROBLEM TO BE SOLVED: To provide a temperature hysteresis indicator which is easy to industrially produce and is a temperature hysteresis indication medium stuck to an object and undergoing an irreversible change when the object is exposed to an environment of a temperature outside the administration temperature. SOLUTION: The temperature hysteresis indicator is prepared by forming a thermosensitive recording layer containing a normally colorless or light-colored electron-donating dye precursor and an electron-accepting compound which causes the dye precursor to develop a color and a temperature-sensitive layer containing a temperature-sensitive substance having a specified melting point in the given order. COPYRIGHT: (C)2004,JPO