Abstract
Plastic film is often stored or transported as a wound roll, and it is placed in a different ambient temperature when it wound. Then the in-roll stress will vary with roll temperature change and the time due to thermo-viscoelastic property of the film. As a result, it could lead wound roll defect such as slippage or wrinkling. For the problem, it is extremely important to theoretically estimate the stress. In this study, a winding model for prediction of the stress, considering thermo-viscoelasticity and creep compliance subjected to the roll temperature and the stress changes is presented and experimentally verified. Prediction expressions of the creep compliance are applied on the winding model, which are experimentally determined by applying generalized Voigt mode using a polypropylene film.