Emissivity glass is a coated glass on one face of the glass and has the effect when used in the construction of a double glazed unit of reflecting the long wave radiation or heat back into the room.
All emissivity glass has a slight tint which varies from manufacturer to manufacturer. There are two types of emissivity glass, one is referred to as Hard Coat and the other Soft Coat.
The Hard Coat is applied during manufacture referred to technically as Pyrolitic and Soft Coat is applied to the glass after the glass has been manufactured in a vacuum spluttering process.
Whilst the Soft Coat process tends to have improved emissivity or insulation value, some Soft Coat tend to have a more noticeable tint which affects light transmission.
Slimlite is manufactured with Pilkington K, Hard Coat, as best all round product, has very good emissivity or insulation value and also importantly good light transmission of 75% compared with clear glass at 81% and therefore reasonable solar gain at all daylight times.
Overall the use of Pilkington K in the construction of a Slimlite Double Glazed Unit ensures good light transmission and when glazed in situ, is visually difficult to detect from clear glass.
