To easily and inexpensively manufacture a biodegradable, transparent and gas barrier film with a simple apparatus by forming a polyvinyl alcohol coating layer on at least one surface of a polylactic acid oriented film.
To manufacture the biodegradable, transparent and gas barrier film of a laminated structure as a packaging material, a polyvinyl alcohol coating layer is formed and laminated on one surface of the oriented film. As the used polylactic acid film, a monoaxially or biaxially oriented film is preferable. As the polyvinyl alcohol, a resin obtained by saponifying an acetate group of the polyvinyl acetate by 95% or above is desirable. The formed coating layer preferably has a thickness in a range of 0.01 to 20 μm. Thus, a film having a mechanical strength adapted to a packaging material, high flexibility and gas barrier properties is obtained.
SAWAI TORU
TAKEISHI KAZUMICHI
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