Apr 19

Written by: Joseph Coupal
4/19/2010 2:48 PM

Why is some stretch film called CAST and some BLOWN? Is this plastic or gum?

Originally, all stretch wrap was blown, a process much like blowing bubble gum. Resin is heated and passed over an opening through which air is blown. Most state-of-the-art film today is cast. It is extruded through rollers and "laid out" in sheets. This process allows the film to be made in multiple layers. The layers allow the film to be made with cling on only one side. This optional one-sided-cling film is great where you don't want one pallet to stick to the one next to it. Also, these films layers can make the film stronger by adding tough layers to the inside. Cast film is also clearer and quieter coming off the roll.

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