They are used in a number of applications including forehead thermometers. By pressing the thermometer to the forehead the temperature generated turns the thermochromic ink translucent, this reveals the temperature gauge colour bars, which are printed in normal ink.

Other inks are available for promotional use, enhancing printed materials. Thermoreactive inks can be used to reveal graphics is a warm hand is placed over them or if placed in a fridge. As well as inks that react to changes in temperature, some inks react to ultraviolet light. these are known as photochromic.

Other inks are available for promotional use, enhancing printed materials. Thermoreactive inks can be used to reveal graphics is a warm hand is placed over them or if placed in a fridge. As well as inks that react to changes in temperature, some inks react to ultraviolet light. these are known as photochromic.