ROOFING MATERIAL CONTAINING NON-LEACHABLE FIRE RETARDANT

摘要

A fusible phenolic resin and a dialkyl-N, N-bis (hydroxyalkyl) aminoalkyl phosphonate are condensed to form a water-insoluble resin having fire retardant properties. Fire resistant materials are made by causing the condensation to occur in situ when a normally flammable material and the reactants are mixed and the mixture is heated at 250.degree.F to 480.degree.F. Wooden articles such as molded hardboard roofing shingles of this invention do not lose their fire resistance after being soaked with rain repeatedly.