The Color change of these paints is caused by a temperature change. As soon a certain Temperature has been reached ( for example with red +22°C ) , the color red dissapears and becomes colorless when it cools down to +22°C or less the original color appears again.
Temp. Temperature reactive paint Yellow 20 °C Yellow to White
Red 22 °C Red to White
Blue 31 °C Blue to White
Violet 36 °C Violet to White
Black 43 °C Black to White