Fireproof glasswork

Abstract

The invention relates to a fire screening glazing panel and a method for forming the panel. The panel is composed of at least two structural plies, at least one of which is a vitreous sheet, and a layer therebetween composed at least in part of a heat convertible barrier forming material, which material forms a solid porous or cellular thermally insulating body when subjected to sufficient heat, as during a fire. The barrier forming material is an hydrated metal salt selected from the group consisting of aluminates, plumbates, stannates, alums, borates, and phosphates. The barrier forming material does not significantly reduce the transparency of the structural sheets, if they are transparent, even over extended use during normal conditions.

Dependencies are inferred from the claim text.