| 摘要 |
<p>Additional panels of film are welded onto the surface of a continuous moving thermoplastic film by passing the film between a rotating mandrel and a moving belt applying pressure against part of the circumference of the mandrel, and where the mandrel surface incorporates at intervals a series of welding plates and of groups of pressure rollers. An ancillary belt nip can periodically draw individual reinforcement panels out from a stock sheet. Used for reinforcing zones of a film to provide hand holes for carrier bags to be made from the continuous film. Process does not interrupt the motion of the base film which might otherwise be able to move continually through folding, welding and cutting units.</p> |
