The blue pigments may not be heat resistant and may have faded or shifted from the heat used in the foil stamping process. Certain ink pigments, most commonly blues and greens, can change color when exposed to heat or alkaline solutions; this is commonly referred to as "pigment burnout." Foil stamping, laminating, and imprinting on a toner-based digital press with a fuser roller can expose pigments to enough heat to cause pigment burnout. Coatings, especially aqueous coatings, may be alkaline and along with heat from the drying operation can cause pigment burnout. When ordering inks, specify if the ink is to be used with a coating or any additional process involving heat.