Intumescent putty or mastic

Abstract From the Canadian patent

A composition suitable for use as a putty or mastic comprises as a solid phase, fine particles of solid intumescent material or which when subjected to elevated temperature as under fire, conditions, form intumescent material the fine particles being, mixed in a solution of a flexible stretchable film-forming adhesive polymer in a volatile solvent. The solid phase may comprise a carbonific, a spumific, an activator and a binder. The carbonific may be a polyhydroxy compound. The spumific may be dicyandiamide or guanidine. The activator may be an ammonium phosphate. The binder may comprise melamine formaldehyde resin. The solid phase may comprise vinyl acetate polymer as additional binder.