Process for controlling the curl of photographic film.

摘要

A process of making biaxially oriented polyethylene terephthalate photographic film having a controlled amount of curl in the longitudinal direction, where the longitudinal stretching of the film is done while the film is asymmetrically heated across its thickness, and the stock roll of produced film is heat-tempered. The stock roll of film thus produced may further be longitudinally slit, cut and rewound on small cores in a direction in which the core-set curl opposes the longitudinal curl induced in the film during the longitudinal stretching.