Phase Change Material (PCM) is a substance with a high heat of fusion which, by melting and solidifying at certain temperatures is capable of storing and releasing large amounts of energy. PCM’s either absorb or release heat when the material changes from solid to liquid and vice versa.
When a PCM is cold, it releases a large amount of energy at a relatively constant temperature. Conversely, when energy is applied, it absorbs a large amount of heat from the environment. This allows for us to create a temperature neutral sleeping environment where temperatures do not fluctuate to the extremes.