Process and apparatus for pyrolytically coating glass

摘要

Apparatus for pyrolytically forming a metal compound coating on an upper face of a hot glass substrate 1 in sheet or ribbon form comprises conveyor means 2 for conveying a the substrate along a path also indicated at 1 in a downstream direction 3, a roof structure 5 defining a coating chamber 6 opening downwardly onto the path 1 and means 7 for discharging coating precursor material into the chamber 6. Upstream of the coating chamber 6 there is an antechamber 25 which communicates with the coating chamber 6 via an entry slot 24 which is defined in part by the path of the substrate 1, and via which gas can be caused to flow into the coating chamber 6 so as to form (when the apparatus is in use) a blanket layer which covers the upper face of the substrate 1 along a first part of the length of the chamber 6. Means 26 is provided for controllably preheating the gas forming the blanket layer. In operation, the gaseous environment in the immediate vicinity of the upper face of the substrate at least in the zone at which coating formation commences, is controlled by feeding preheated gas in a downstream direction into the chamber 6 to enter the chamber in contact with the substrate and form a blanket layer which covers the substrate at least as far as that zone.