To obtain the subject film having excellent slipperiness under high- humidity condition while keeping the transparency and surface gloss of the film by forming protrusions having a specific size on a polyamide film surface at a specific density and hydrophobicizing the film.
This polyamide film has a surface roughness characterized by the presence of 6-30/mm of protrusions having a height of ≥0.06μm from the center line measured by a surface-roughness tester, a static contact angle of ≥64° with water at 23°C, a haze value of ≤10% and a gloss of >110. The film can be produced by compounding a polyamide resin with a surface- roughening substance, especially inorganic fine powder, concretely gel-type silica, etc., and a surface-hydrophobicizing substance, especially a long-chain aliphatic bisamide compound such as N,N'-ethylenebisbehenamide, forming the composition in the form of a film and drawing the film at an areal draw ratio of ≥3.
TANAKA SHOICHI
NISHIYAMA MASAO
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