What does the increasing use of sharp, eye-catching graphics on flexible plastic packaging have in common with the need for faster production to drive down costs? Both are important and growing trends in the packaging industry, and both depend upon the properties of advanced slip agents, which are used to reduce the coefficient of friction (COF) in bi-axially oriented polypropylene (BOPP) film. Slip agents, or additives, overcome the film’s natural tackiness, enabling it to move smoothly through high-speed converting and packaging equipment.
But not all slip agents are equally effective. Traditional organic waxes such as erucamide and oleamide deliver good slip performance, but readily and continuously migrate from the film’s surface. This migration can affect the appearance and quality of packaging materials by increasing the haze level of clear film. It can also negatively affect downstream printing and vacuum metallization operations when the additive transfers from the slip-treated face to the corona-treated face during film winding and storage. The presence of a slip additive on the corona-treated face of the film can cause non-consistent coating or metallization called the “fish eye” effect.