Athermic treatment, applied to the sheets during extrusion, consists in creating a dispersion of special chemical compounds throughout the sheet that are capable of absorbing the infrared component of solar energy, which is then released back outside in the form of heat (R_est).

The particular finish is suitable in all those applications where a low light transmission, associated with a low energy transmission, is required; it is available in Athermic Gray (0777) or in Bi-colour versions such as Athermic Gray / Opale (0737) Blue Athermic / Opale (0537), ideal for integrating different colours to the architectural composition.