Patent ID: 9650290
Date: 2017-05-16
CPC Classifications: A01M,C03C,E06B

Claim:
1. An IG window unit comprising: a first glass substrate; a second glass substrate spaced apart from the first glass substrate via at least one spacer so as to provide an air space between the first and second glass substrates, said air space optionally comprising an inert gas; a UV reflecting coating provided on the first glass substrate and on an exterior surface of the IG window unit so as to face an exterior of a building in which the IG window unit is to be mounted; a low-E coating comprising at least one IR reflecting layer comprising silver provided on the other side of the first glass substrate, so that the first glass substrate supports and is located between the UV reflecting coating and the low-E coating; wherein the UV reflecting coating is not part of a low-E coating and does not contain any IR reflecting layer of silver or gold; wherein the UV reflecting coating is patterned so that the UV reflecting coating is not provided continuously across the entire first substrate; wherein the UV reflecting coating comprises first, second, third, and fourth layers in this order moving away from the first glass substrate, and wherein the first and third layers are high index layers having a refractive index of at least 2.25 and the second and fourth layers are low index layers having a refractive index of no greater than 1.8, where refractive indices are measured at 550 nm; wherein the first, second, third and fourth layers are each dielectric layers that are substantially transparent to visible light; and wherein the IG window unit has a visible transmission of at least 50%, and the UV reflecting coating reflects at least 40% of UV radiation in at least a substantial part of the range from 300-400 nm.