The present invention provides a method and an apparatus for producing a packaging sleeve of polygonal cross-section, particularly adapted to be foldably collapsed, wherein circular or tubular sleeve stock is formed on a stationary spindle or mandrel from a plurality of glued, thin layers of paper, fabric,...http://www.google.es/patents/US4260446?utm_source=gb-gplus-sharePatente US4260446 - Method and apparatus for producing a collapsibly foldable packaging sleeve having a polygonal cross-section
Method and apparatus for producing a collapsibly foldable packaging sleeve ...
