TLC is an acronym for Thermochromic Liquid Crystals.
Thermochromic describes chemicals that change color in response to changes in temperature.
What is a Liquid Crystal?
Liquid Crystals are chemicals that can exist in a special state of matter, which is called the liquid crystal state. The liquid crystal state of matter exists between the solid state and liquid state.
Melting point is the temperature at which a solid transforms into its liquid state. Freezing point is the temperature at which a liquid transforms into its solid state. Liquid crystals do not melt or freeze. Instead, they are in a special state of matter with characteristics of both solids and liquids. In the liquid crystal state, LCs flow, thus in this state of matter the chemical is a fluid.
The liquid crystal state for the TLC Dot Stickers is between 25°C to 31.5°C. Different liquid crystals have much different temperature characteristics, and it is up to the designer of a liquid crystal product to select a liquid crystal with a liquid crystal state that best works for the product. For example, liquid crystal thermometers need a wider temperature range than do the TLC dot stickers used to introduce characteristics of LCs.