Patent ID: 6960374

Claim:
A biodegradable bag comprising a laminate of a biaxially oriented film of which the major component is a polylactic acid-family polymer, and a film consisting of aliphatic polyesters having the structure of formula (1) below and having a crystallizing melting heat Δ Hm (J/g) of 45≦Δ Hm≦55, wherein said biaxially oriented film is biaxially oriented by a successive orienting method in which longitudinal orientation is carried out by a roll method and lateral orientation is carried out by a tenter method, or by a simultaneous biaxially orienting method in which longitudinal and lateral orientations are simultaneously carried out by use of a tenter, said bag being made by heat-sealing said laminates so that said biaxially oriented film of which the major component is a polylactic acid-family polymer will be an outer layer, wherein R 1 and R 2 are alkylene groups or cycloalkylene groups having a carbon number of 2–10, n is the degree of polymerization necessary for the weight-average molecular weight to be 20000 to 300000, n R 1 's and R 2 's may be the same or different, and in the formula, instead of the ester-bond residue, urethane-bond residue and/or carbonate-bond residue may be contained by up to 5% of the weight-average molecular weight.