To prevent a PEN(polyethylene-2,6-naphthalate) film from degrading a superior mechanical strength, to improve a tear characteric that is a defect of the PEN film and to satisfy a superior cutting characteristic, a superior output characteristics used as a magnetic tape and a rolling habit of curling used as a photographic base film.
A biaxial orientation laminated film is constituted of three layers or more having at least one layer formed of a polyethylene-2,6- naphthalate. In this case, a crystallinity Xc of the outermost layer of at least one side of the biaxial orientation laminated film is 2-5% lower than a crystallinity XA of a full film, and 50% or more of the thickness of the full film is constituted of the layer formed of a polyethylene-2,6-naphthalate.
OKAMOTO KATSUYA
MIYAKE TORU
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