These color-changing inks can be us

These color-changing inks can be used in screen-printing and offset lithography, along with other printing processes. They are combined with standard inks and are used for an ever-widening range of applications, from textiles to product stickers. Using basic color theory, when a leucodye color like blue is added to a red ink, it produces purple ink. When cool, the product will be purple, and when the temperature rises, the color will change to red. Any number of colors can be formulated in this way. The temperature range for such changes can also be varied.