Shape retaining material and method for producing the same

A shape retaining material, which is a fibrous, band-like, or sheet-like stretched formed material comprising 100 parts by weight of a high-density polyethylene resin having a weight-average molecular weight of 100,000 to 500,000 and a density of 0.945 to 0.960 g/cm3 and 3 to 50 parts by weight of an ethylene-α-olefin copolymer obtained by copolymerizing ethylene with an α-olefin having 4 to 10 carbon atoms, the copolymer having a density of 0.935 to 0.960 g/cm3, the difference in density between the copolymer and the high-density polyethylene resin being ±0.020 g/cm3 or less, wherein the material shows, after being bent at an angle of 180 degrees in TD, i.e., in a direction orthogonal to the stretching direction (MD), held in the bent state for 1 minute, released, and left for 5 minutes after the release, a return angle of 15 degrees or less;

• and shows, after being bent at an angle of 180 degrees in MD, i.e., in a direction parallel to the stretching direction (MD), held in the bent state for 1 minute, released, and left for 5 minutes after the release, a return angle of 25 degrees or less.