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Rigid polyurethane foam is light in weight, high in strength and good in heat insulation. This kind of plate is covered mostly face layer, reason is the sandwich core board that is core material with hard bubble or call compound board. Surface layer soft, hard material can be. Soft surface materials are kraft paper, asphalt paper, glass fiber fabric, aluminum foil, and so on. Hardiness material has colour steel, marble, plasterboard, plank and profile to wait.

Composite plate processing methods are generally divided into Continuous compound molding、Discontinuous compound molding、Hard foam cutting and so on。

Classification of polyurethane sheet

According to production process：Continuous method, intermittent method (molding, box foam)

According to the surface：Double hard surface, double soft surface, soft and hard surface

According to foam structure：PUR 、PIR