| 摘要 |
PURPOSE:To endurably located a port, by a method wherein a film of a polyethylene bag and a film-strip for a port, made of a similar material to that of the bag, are welded together by heating at an approximately central section thereof, and both sides of the film strip, which are risen upward after a hole is made at a center of the adhered portion, are welded together by heating at both edges thereof facing and positioned opposite to each other. CONSTITUTION:A film strip 2 for a port made of the same material as that of a bag film 1 is superposed on the bag film 1 made of a polyethylene material, the films 1 and 2 being welded together by heating at an approximately central portion of the film strip 2 for the port to form a welded portion. A hole 4 is made in the center of the welded portion 3 such that the fringe of the welded portion is left as it is. Both sides 2a and 2a', in the direction of a long side, of the film strip 2 for the port are risen upward for being superposed together, and simultaneously, both side edges thereof, facing and being positioned opposite to each other, are welded together by heating to form the port of the polyethylene bag. |
