How do irreversible thermochromic pigments change color?

In daily life, we encounter many reversible temperature change effects, such as: color-changing cups, color-changing toys, color-changing clothes, color-changing jewelry. These color-changing products will show different colors depending on the temperature.

Our irreversible thermochromic pigment is that when the temperature is at or above a certain fixed temperature, it can produce semi-permanent color change, and the original color disappears and is locked. Moreover, under everyday conditions, the original color does not return to manifestation, only when the temperature falls below -10 degrees, the color appears slowly.

Once the temperature reaches the set color change temperature, the color begins to change slowly and the original color gradually disappears. However, if the temperature does not reach the upper limit of the set point temperature, the new colorless area will revert to its original color. Once the temperature reaches the upper limit of the fixed value temperature, the colorless area is locked in a semi-permanent state. To return to its original color, the temperature must be lowered to the lower limit of the fixed value temperature. When the temperature drops to the lower limit of the maximum set point temperature, the entire original color area is revealed. If the lower limit of the maximum set point temperature is reached too quickly, the original color may not be fully visible. For best results, once the lower limit of the set point temperature is reached, the lower limit of the maximum set point temperature must be slowly and gradually reached. Due to environmental conditions such as humidity, there may be slight differences in the range of setpoint temperatures. For example, the upper limit of the setpoint temperature will be higher in a dry environment than in a humid environment.