Thermo-sensitive inks react to heat and cold or become visible only within certain temperature ranges. With some creativity, the possibilities are numerous. Thermo-sensitive inks can be used for instance on bubble-bath and bath products to determine the correct temperature of the water. "Cool me" appears when a cold drink has become too warm. A product is steam-sterilized when a particular shade of colour appears. There are numerous possibilities. As already mentioned: creativity is the key. Ink segments can be set to react in a specific way within certain temperature ranges. Your product becomes more attractive and has many more uses.