Patent ID: 7870704

Claim:
An insulating glazing unit constructed and arranged for use in a leaf of a refrigerated enclosure, the glazing unit comprising: at least first and second glass substrates, the first glass substrate having a first external face and a second face, the second glass substrate having a third face and fourth external face, the glazing unit is constructed such that when installed in a leaf and the leaf is in a closed position the first external face is exposed to an external environment and the fourth external face is in contact with an environment inside a refrigerated enclosure; at least one spacer of low thermal conductivity retaining the first and second glass substrates spaced apart, the spacer having a thermal conductivity of less than 1 W/m.K; a low-E (low-emissivity) coating at least partly on a face of at least one of the glass substrates having an emissivity not exceeding 0.3; and an anti-frost coating on at least part of the fourth external face, which avoids formation of fogging or frosting on the fourth external face when the glazing unit is used on a refrigerated enclosure and opened to take merchandise out of the enclosure or for restocking the enclosure so that the merchandise can be easily seen through the glazing unit, wherein, an airspace defined between the first and second substrates is filled with at least one rare gas; the glazing unit contains no heating element; the glazing unit has a thermal conductivity coefficient U of less than 1.2 W/m 2 .K with a gas filling of at least 85%; and the glazing unit has a light transmission of at least 75% and a light reflection of less than 18%.