Abstract: A base film for a photographic film, wherein (a) the refractive index (nz) in the thickness direction is at least 1.498, (b) the haze value is 2.0% or less, (c) the base film has one direction in which the tan.delta. value, at 80.degree. C. by tensile viscoelasticity at 0.05 Hz, is 0.09 or less, (d) the anti-curling ratio at 70.degree. C. is at least 45%, (e) the thickness is in the range of from 40 to 120 .mu.m, and (f) the base film is formed from polyethylene-2,6-naphthalendedicarboxylate as a substantial raw material. This base film has various performances such as anti-curling properties, transparency and lubricity, suitable for use in a photographic film.

Abstract: A film for a thermosensitive stencil printing base sheet, comprising a biaxially stretched film of a thermoplastic resin having a thickness of 0.2 to 7 micrometers, said film showing at least two fusion peaks in its DSC temperature elevation measuring chart (the rate of temperature elevation 20.degree. C./min.), at least two fusion peaks having the following relation:T.sub.mp (max).ltoreq.260(.degree.C.)T.sub.mp (min).gtoreq.90(.degree.C.).DELTA.T.sub.mp .gtoreq.10(.degree.C.)5(cal/g).ltoreq..DELTA.Hu(total).ltoreq.13(cal/g)0.05.ltoreq..DELTA.Hu(min)/.DELTA.Hu(total).ltoreq.0.9whereinT.sub.mp (max) is the temperature (.degree.C.) of the fusion temperature on the highest temperature side,T.sub.mp (min) is the temperature (.degree.C.) of fusion peak on the lowest temperature side,.DELTA.T.sub.mp is T.sub.mp (max)-T.sub.mp (min),.DELTA.Hu(total) is the total fusion energy (cal/g), and.DELTA.Hu(min) is the fusion energy (cal/g) of the fusion peak on the lowest temperature side.