Constructs the PVC plastic corner bead to be suitable for the plaster tablet wall and the heat preservation system wall corner, the window side positive angle and so on many place positive angles processing, this corner bead can glue the mortar with the heat preservation completely to unify, forms the firm positive angle heat preservation protection system, does not rust, bears the alkali, bears the aging, excels in guards against creates, effectively guaranteed positive angle vertical smooth, corner bead two side network structure, causes it caking closely, is more reliable.