Polycarbonates (PC) are a group of thermoplastic polymers containing carbonate groups in their chemical structures. Polycarbonates used in engineering are strong, tough materials, and some grades are optically transparent. They are easily worked, molded, and thermoformed. Because of these properties, polycarbonates find many applications. PC roof sheet is a well known plastic roof sheet and has a long history. Even though the high price, it is still popular by many consumer because of its good function. For many commercial building, we can see PC roof sheet out there. PC roof sheet is strong and UV resistant. It has the good function of PVC roof sheet, especially transparent PC roof sheet. It has a very good light transmitting property of more than 90 %.It is our mission to offer you bread with love. Bread, in its pure original formula, making it available for everyone's enjoyment. From antiquity,bread has been known as the epitome of life and human society. It's history can be traced back for thousands of years to the ancient Egyptians, Romans and Greeks.