The biaxial stretching PET film and its production manner where for the SMD film condenser mechanical property and contractile property are improved

摘要

(57) Abstract As for this invention, being monolayer or the multilayer biaxial stretching film where thickness is 10 millimicrons or less, the mechanical strength coefficient MC is calculated from the below-mentioned formula, the range of the MC above the 2, is larger than 0 desirably, to be more desirable is larger than 0.5, especially is desirable and 1 or more at the same time 50 or less, desirably 30 or less, especially to be desirable regards the film which features that they are 5 or less. (In the above-mentioned formula, as for S200TD coefficient of contraction of the cross direction in the 200 (%), as for S200MD coefficient of contraction of the longitudinal direction in the 200 (%), as for T2% the film 2% the temperature which is expanded, elastic modulus of cross direction (N/mm2) shows E _TD respectively under the fixed tension of 5N/mm2).