| 摘要 |
A tenter oven wherein blowing ports which blow air heated to a prescribed temperature and suction ports which recover air in said tenter oven are arranged so as to extend along the transverse direction of the film, said tenter oven comprising clips which grip both end portions of the film in the transverse direction of the film; clip rails which are running paths of said clips; and one or more zones partitioned with walls except for the openings for transporting the film along the film transport direction; wherein said zone is constituted by one or more chambers; said tenter oven further comprising shield plates at a position between one end of said blowing port in the transverse direction of the film and the clip-gripping portion closest thereto, and at a position between the other end of said blowing port in the transverse direction of the film and the clip-gripping portion closest thereto, respectively, said shield plates being within planes substantially perpendicular to the film plane and substantially parallel to said clip rails. By the tenter oven, the irregularity in temperature in the transverse direction of the film is decreased, thermoplastic resin films having uniform characteristics and thickness in the transverse direction of the films can be produced, the energy consumption necessary for heating the film can be saved, and the defects due to the deposit of the oligomer or the like can be decreased. |
