Process for producing intumescing layer on a glass substrate surface, the glass substrate witch such a layer and a layered glass product

摘要

Process for the production of an intumescent fire resistant layer by drying a waterglass solution on the surface of a glass substrate are carried out in the presence of a salt of a carbonic acid or an alpha-hydroxy carboxylic acid such as potassium citrate. The drying is preferably carried out at a rate which reduces of pH of the solution by no more than 2 units during an initial drying period of 5 hours. The resulting interlayers provide improved fire resistance.