PURPOSE: To obtain an inner packaging bag and a packaging container free from bad smell and having improved durability by the use of a laminated film containing no anchor coat agent, wherein an ozonized, extruded laminate resin is pressed on a plastic base material to which a specific surface oxidation treatment has been applied.
CONSTITUTION: A surface oxidation treatment is applied to at least one surface of a plastic base material and an ozonization treatment is applied to at least one surface of a film prepared by melt-extruding an extruded laminate resin at a temperature of 180-340°C and both the material and film are compressively bonded to each other to form a packaging film or sheet containing no anchor coat agent, wherein a surface treatment is effected so that the relationship Δ(OC)≥0.08 is established when the plastic base material is a polyester resin and the relationship Δ(O/C)≥0.05 when the base material is other than a polyester resin. However, Δ(O/C)=(O/C)*-(O/C)°, where (O/C)° represents the ratio of number of atoms between O and C measured by ESCA method with respect to a surface to which a surface oxidation treatment has not been applied, and (O/C)* represents the ratio of number of atoms of a surface to which a surface oxidation treatment has been applied.
ISHIBASHI FUMIO
SHIGEMATSU YUJI
TAKAHATA HIROAKI
KUBO KOJI
GOTO HIROTSUGU
