Phase Change Materials is a collective term for materials with the capacity to alter their aggregate state within a certain temperature range: from solid to liquid or from liquid to solid. Like water, for example, which turns into ice at 0°C and evaporates at 100°C.
In order to incorporate Phase Change Materials in textiles, they are enclosed in a protective sheath (microcapsules with only a few micrometer diameter). This prevents leakage during the liquid phase and the garment remains weatherproof and resistant to washing and dry-cleaning. The suitable carrier materials for these microcapsules which enclose the Phase Change Material are, for example, coatings and foam which can be applied to various materials such as fleece, tricots or fabric.
The microcapsules react to temperature fluctuations. They alter their aggregate state at a certain temperature: from liquid to solid and vice versa. The Phase Change Material in the microcapsules is set to a certain temperature range. If the body temperature or the ambient temperature rises, they store the excess heat. When the temperature drops again they release the previously-stored heat once again.