Reversible temperature-indicating composition

摘要

A new reversible temperature indicating composition for use in temperature indicating instruments is diclosed which is capable of accurate temperature indication in a variety of colors and characterized by a minimum range of hysteresis so that the marking drawn in this composition can decolor at or close the temperature at which its coloring takes place. In addition, the composition can provide a wide variety of hues and can be readily prepared. These and other advantages are provided by the inclusion as a main ingredient of an ester compound having DELTA T value, defined DELTA T=melting point-clouding point, in the range under 3 DEG C., the value that determines a desirably small range of hysteresis.