Review of the Application of Thermochromic Materials in the Preparation of Smart Textiles

Thermochromic or thermochromic materials change color reversibly with an external stimulus, i.e. temperature. It is used to change color in a certain environmental range to prepare smart textiles. A variety of thermochromic materials are available, which can be classified into direct and indirect. Thermochromic materials change color in a subtle and reversible way with increasing and decreasing temperature and can change from colored to colorless or vice versa or from one color to another. These materials can be combined with ordinary colors and get newer colors. Thermochromic dyes cannot be used on direct textiles due to the surrounding environment and low reactivity. They are usually used in the form of microcapsules. Thermochromic materials are used to produce smart textiles through dyeing or printing. These textiles are used in various fields such as wearable displays, sensors, insulation materials, anti-counterfeiting materials, and military industries. Textiles printed with thermochromic microcapsules have good stability properties but are very sensitive to light, solvents, and high temperatures.