| abstract |
PROBLEM TO BE SOLVED: To remarkably improve the releasability of a polypropylene resin layer which is a protective layer from a polyethylene resin layer which is an anticorrosion layer, and to multiply coat the resin without being restricted by the resin composition of polyethylene and polypropylene. The present invention provides a multi-coated steel pipe which can be used for steel pipes, has excellent low-temperature impact resistance, and has excellent extrusion properties, mechanical strength, and weld strength. SOLUTION: In a multi-coated metal tube in which a polyethylene resin layer is coated as an anticorrosion layer on the outside of a metal tube and a polypropylene resin layer is coated on the outer surface as a protective layer, the polyethylene resin layer and the polypropylene resin layer At least one layer contains at least 0.0001 to 20% by weight of an antioxidant or 0.0001 to 40% by weight of a nucleating agent. |