02.13.07
A biaxially oriented film was recently patented. The film includes a polylactic acid resin, which has a storage modulus E? at 80° C in at least one of a longitudinal direction (MD direction) and a width direction (TD direction) of the film, of from 10 MPa to 3,000 MPa, as determined by a test method for temperature dependency of dynamic viscoelasticity in accordance with JIS K7198 (method A). The film also features a heat shrinkage of not higher than 10% upon heating at 80° C for 10 seconds. The film has a tear strength in the width direction (TD direction) of 10 to 200 mN, as determined in accordance with JIS K7128 (method B) and is drawn at a ratio of 5.2–7 in the width direction (TD direction).