Patent ID: 6210784
Filing Date: 2001-04-03
Classification: C03C,Y10T

Abstract:
Transparent substrate provided with a thin-film stack including at least one low-emissivity metallic layer with infrared reflection properties arranged between underlying and overlying dielectric-based coatings, the underlying coating having a wetting layer based on zinc oxide ZnO, or aluminum-doped zinc oxide ZnO:Al, which is directly in contact with the metallic layer, wherein each of the two coatings based on the dielectric material comprises at least one layer with a high refractive index of greater than or equal to 2.2, and wherein the overlying dielectric-based coating has the following sequence of layers deposited in the order stated;a) first layer(s) of material(s) having a refractive index n.sub.i-2 of less than 2.2;b) intermediate layer(s) of material(s) having a refractive index n.sub.i-2 ;c) last layer(s) of material(s) having a refractive index n.sub.i substantially equal to n.sub.i-2.wherein n.sub.i-1 of the intermediate layer is at least 0.3 less than n.sub.i of the last layer; and further comprising a layer with refractive index that is greater than or equal to 2.2 arranged between the reflective metallic layer and the sequence of layers the overlying dielectric-based coating.