Provided is a transparent substrate with a multilayer thin film coating, in which the multilayer thin film coating includes a lower dielectric layer, a lower protective layer, a metal functional layer having an infrared reflection function, an upper protective layer, and an upper dielectric layer, which are sequentially laminated on the transparent substrate, the thickness of the metal function layer is 12 nm or more, and the thickness of the lower protective layer is larger than that of the upper protective layer and the thickness of the lower protective layer is 2 nm or more.

A process for obtaining a material including a substrate coated on one of its sides with a coating including a functional layer, includes depositing the functional layer on the substrate, then depositing an absorbent layer on top of the functional layer, then performing a heat treatment by radiation, the radiation having at least one treatment wavelength between 200 and 2500 nm, the absorbent layer being in contact with air during the heat treatment, wherein the ab sorb ent layer ab sorbs at least 80% of the radiation used during the heat treatment and transmits less than 10% thereof.