The pressure-sensitive color inks security ink ink temperature change

The pressure-sensitive ink, also known as non-inversion change ink by AB double ink composition, printing gently a program, it will change color after a few minutes, to restore the original color disappears, called reversible. Colorless ink, print samples colorless when the temperature slowly rises to a certain time, began to change color, color is complete, the color is not achromatic, called irreversible.