Pre-stretched film having improved edges
OwnerDavid J. Smithinventor
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Abstract
Rolls of pre-stretched cling film are used to manually wrap and unitize bulky loads such as boxes on a pallet. Using film that has previously been plastically stretched simplifies the wrapping operation. Unfortunately, however, the pre-stretched rolls of film have edges which are prone to fail during use. The disclosed invention concerns rolls of pre-stretched cling wrap having improved edges that are less prone to fail, and the method and apparatus for producing such rolls.
Claims16
A process for producing a roll of pre-stretched film have improved edges comprising;
- supplying a pre-stretched web of thermoplastic material to slitting and annealing station, slitting the pre-stretched web, thermally annealing the web along the slit line, and winding the slit and annealed material into rolls.
Apparatus for slitting and edge annealing a pre-stretched web of plastic film comprising:
- inlet guide means for directing a web of pre-stretched plastic into a slitting and annealing station, support means for said plastic web in said slitting and annealing station, slitting means for slitting said plastic web and producing a slit edge, annealing means for annealing said web adjacent said slit edge, and discharge guide means for directing said slit and edge annealed web away from said slitting and annealing station.
A roll of pre-stretched film having slit and annealed edges.
Dependencies are inferred from the claim text.