TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The polyamide layer comprises polyamide, stabilizer, antioxidant and inorganic material. The polyamide is polyamide 6, polyamide 66, polyamide 46, polyamide 410, polyamide 610, polyamide 612, polyamide 614, polyamide 613, polyamide 615, polyamide 616, polyamide 11, polyamide 12, polyamide 10, polyamide 912, polyamide 913, polyamide 914, polyamide 915, polyamide 616, polyamide 1010, polyamide 1012, polyamide 1013, polyamide 1014, polyamide 1210, polyamide 1212, polyamide 1213, polyamide 1214, poly(terephthalic acid adipamide), poly(terephthalic acid azelamide), poly(terephthalic acid sebacamide), poly(terephthalic acid dodecamide), adipic acid adipamide/terephthalic acid adipamide copolyamide, terephthalic acid adipamide/isophthalic acid adipamide copolyamide, poly(adipic acid isophthalamide), terephthalic acid adipamide/terephthalic acid 2-methylglutaramide, adipic acid adipamide/terephthalic acid adipamide/isophthalic acid adipamide copolyamide, or polycaprolactam-terephthalic acid adipamide. The polypropylene alloy layer comprises polypropylene or modified polypropylene and engineering plastic. The engineering plastic is polyamide or polyphenyl ether. The modified polypropylene comprises: a blend of polypropylene and stabilizer; a blend of modified polypropylene, grafted polypropylene and a heat stabilizer; or blend of polypropylene, heat stabilizer and inorganic filler. The inorganic filler is calcium carbonate, titanium dioxide, barium sulfate, mica, talc, kaolin, glass micro-bead or glass fiber. The polyethylene comprises low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), 2-8C olefin grafted polyethylene or copolymer of ethylene, maleic anhydride grafted polyethylene and silane grafted polyethylene. The ethylene copolymer containing epoxy group is ethylene, acrylic ester and glycidyl methacrylate terpolymer. The protruding structure is a pattern, which is rhombus or ellipsoid, having an average rhombus edge length or average ellipse diameter of 5-100 mu m, distribution density of 1x 102 to 4x 106/cm2, and protrusion height of 5-100 mu m. The base film layer, weather-proof layer, reflective layer and adhesive layer respectively has a thickness of 50-500 mu m, 10-100 mu m, 10-200 mu m and 10-200 mu m. Preferred Method: The method comprises embossing a convex structure on the weather-proof layer while molding using a cooling roller having a concave structure.