Patent ID: 7625194
Filing Date: 2009-12-01
Classification: B29C

Abstract:
1. A tubular resin film manufacturing apparatus comprising: a stretching section including a mandrel formed of a porous material for exuding gas from inside toward a surface of a tubular resin film so as to stretch said tubular resin film; a maintaining section including a mandrel formed of a porous material for exuding gas from inside toward a surface of the tubular resin film so as to maintain a shape of said tubular resin film stretched; a plurality of rollers arranged around a circumferential direction of the tubular resin film on an inner surface and an outer surface, respectively, downstream of the maintaining section to pinch the tubular resin between inner rollers and outer rollers for transporting the film; the inner rollers and the outer rollers cooperating to transport the stretched tubular resin film downstream of the maintaining section while maintaining the tubular shape of the film and a plurality of rollers arranged along the circumferential direction of the tubular resin film on the inner surface and the outer surface, respectively, of the tubular resin film upstream of the downstream rollers for transporting the film, wherein said downstream rollers are rotated at a speed faster than the upstream rollers to stretch the resin film in a longitudinal directional.