Heat reflective substrate, manufacturing method therefor, and window glass

Abstract

The present invention relates to a heat ray reflecting substrate including: a dielectric substrate; and a heat ray reflecting film formed on at least one main surface of the dielectric substrate, in which the heat-ray reflecting substrate has a radio wave transmitting region in at least a part of the at least one main surface of the dielectric substrate in a plan view, the radio wave transmitting region includes a slit portion where the heat ray reflecting film is not present, and in the radio wave transmitting region, a solar heat gain coefficient (g0) in a region including no slit portion and a solar heat gain coefficient (g1) in a region including the slit portion satisfy the following formula (a): g1<(1−f2)·g0+f2α (a), provided that f2 is a designed aperture rate, and α is a solar heat gain coefficient of the dielectric substrate.

Dependencies are inferred from the claim text.