... of PVC sheet: Beijing Oyuan Shengfa Plastic Co.,Ltd. Formerly known as yuanguo plastic factory of wen' ... the establishment of Beijing Oyuan Shengfa Plastic Co.,Ltd. development of foreign users, after several years ... on this basis, Beijing Oyuan Shengfa Plastic Co.,Ltd. will adopt a more entrepreneurial spirit to develop ... Degao synthetic resin roofing tile is 0.325w/m.k, which is 1/310 of that of clay ...