PU sandwich panel is to select two high-quality color-coated steel, or other precision pressed sheet metal sheet to do, in the middle, such as flame-retardant polyurethane foam liquid, after curing at high pressure foaming under certain conditions, and metal panels strong adhesive made of beautiful, smooth, just tough construction sheet. With fire, heat, water, noise and other characteristics, giving the appearance of the building to bring high-quality results, is the world's most forward-looking energy-saving insulation, green environmental protection type building block.