Contact adhesives used to bond copper-bitumen roofing laminates - enhance resistance to delamination and creep

摘要

Contact adhesives are applied to the interfacial surfaces of a bituminous sheet material and a copper foil to enhance laminar adhesion. Used for prefabrication of impermeable roofing panels. The contact adhesives effect bonding at lamination pressures low enough to leave any embossed patterns in the copper foil undamaged. The adhesive bonded panels have enhanced resistance to delamination by differential thermal changes during wide climatic temp. swings. The adhesives are applied by suitable spray or coating systems, pref. using integrated equipment to pre-anneal the copper foil at about 200 degrees C in an inert gas atmos. and to cast and cool the bituminous layer to about 60 degrees C prior to applying the adhesive. Air jets may be used to devolatilise the coatings of solvent prior to lamination between rubber covered rolls. The adhesives are pref. based on 1:1 or 1:2) chlorinated rubber; neoprene or isocyanate elastomers; or (50:25:10) polyisobutylene rubber + coumarone indene resin + vaseline (petrolatum) oil. The bitumen may be resin- or elastomer-modified.