TEMPERATURE SENSITIVE AND REVERSIBLY MULTI-COLOR CHANGEABLE COMPOSITION AND LAMINATED BODY

摘要

PROBLEM TO BE SOLVED: To obtain a composition which highly sensitively changes a color at high temperatures and effectively indicates multi colors by making the composition contain a mixture of a thermally changeable pigment A having a specific hysteresis width and a thermally changeable pigment B having a specific hysteresis width which changes a color in a color changing temperature range of the pigment A. SOLUTION: A composition of the present invention comprises a thermally changeable pigment A which changes a color showing a big hysteresis width (δHA) of a temperature-color concentration curve, a thermally changeable pigment B which changes a color showing a small hysteresis width (ΔHB) in a color changing temperature range of the pigment A and further a non-thermally changeable pigment C each dispersed in a vehicle containing a binding resin. The composition satisfies all of formulae I, II and formulas: (t1-T2)>=1 deg.C, (T3-t4)>=1 deg.C, T4=33-100 deg.C and T1=23-90 deg.C, wherein T1, T2, T3 and T4 are a complete coloring temperature, a color change initiating temperature, a discoloring initiating temperature and a complete discoloring temperature of the thermally color changeable pigment A, respectively and t1, t2, t3 and t4 are the same temperatures of the thermally color changeable pigment B, respectively.