To properly utilize today’s stretch films and understand how they are supposed to be loaded onto your wrapper, you must first understand “cling”. Cling is a bonding agent added to stretch film to increase the stickiness quality of the film. This is desirable to allow the layers of stretch film applied to bond to the previous layers effectively creating a single wall of stretch film. Depending on the desired effect the bonding agent is applied to one or both sides. It is most commonly applied using co-extrusion where the bonding agent is a layer that is co-extruded during the manufacturing process. Film is supplied as either single side, two sided or differential. Single side is where the cling is only applied to one side of the film. It is applied to both sides on two sided cling film and applied to a little to one side and more to the other side on differential cling film. stretch film cling Rolls of two sided cling films are provided wound on plain center cores. One sided cling films are provided wound on cores that have printed directional arrows on them. Differential cling film cores may or may not have arrows on them. These arrows are used to allow the wrapper operator to consistently load the film on the wrapper. Most all single side or differential cling stretch film is wound on the core so that the cling is on the inside (toward the core) of the film as it comes off, but some are not so you have to be sure you know in order to load your wrapper properly. A simple test is to put one side of the film against itself to see which side sticks together and which side does not. Once you know which side of the film the cling is on, you then need to know whether to load the film on your wrapper with the core arrows pointing up or down. Load the film with the arrows pointing in whatever direction ensures that the cling side of the film ends up toward the inside of the pallet as the wrapper applies the film to the pallet. You do need to worry about film cling as it relates to your use of stretch film for shipping and as it is related to loading the film on your stretch wrapper. Have you ever unloaded a pallets from the truck and found that as you try to pull one pallet off that has rubbed against another during shipment and that it is actually bonded to the pallet it rubbed against? Sometimes the two pallets are bonded together so much that you can actually pull product off of the other pallet as pull one off. If that has happened to you or you have had a customer had it happen with your product, think about cling. A one sided cling film is provided to fix this situation. With the non-cling side of the film on the outside of the pallet, the pallets should not bond together. Pay attention to the film you buy and make sure it has the right cling for your application. Have questions about your clinging situation? Submit them here or contact IPC and we’ll be happy to provide you with a solution.

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