Fibre resistant board - comprising rigid polyurethane foam between metal covered hydrated asbestos boards

摘要

Composite insulation board comprising a rigid foam core sandwiched between two layers of asbestos board covered in turn with a thin layer of metal. Pref. the core is a polyurethane foam expanded by CFCl3 at >=400 g./cm2 to adhere to boards made of hydrated white asbestos coated with aluminium >=0.025 mm. thick. For waterproof fire-resistant panels for use between -186 degrees and +700 degrees C for buidlings, cold storage, etc. The metal layer acts as a water barrier. The asbestos board evolves steam and the core carbonises gradually, to delay the penetration of the board by a fire, without generation of serious quantities of smoke or toxic fumes.