| 摘要 |
<p>PURPOSE:To prevent troubles such as a tear at a holding part of a film, which is ascribable to adhesion between a clip and the film and a dynamical hang-up, and cutting resulting from concentration of stressin the vicinity of the clip, by making a thickness of a clip holding part and its vicinity most suitable. CONSTITUTION:A mean film thickness T in the inside of a clip holding part is made into t+z<=T<=t+7z [(t) is a thickness (mu) of a central part of the film directly before an introduction of a tenter part and z is a draw ratio in the tenter part and is the product of a longitudinal and lateral magnifications]. The film thickness (mu) is made to reduce gradually down to (t) almost linearly in a sphere wherein a film thickness Tc at the tip of a clip of a center side of the film running along the direction of a film width is t<=Tc<=t+3z and a length is identical with a grasping margin of the clip by facing toward the center part running along the direction of a film width. Generation of a trouble at the time of manufacture of a biaxially oriented film made of thermoplastic resin, whose thickness is less than 1mum, based on a tenter method can be controlled in a synergistic state by making use of the film like this.</p> |
