Surface Energy Shift and Gloss Drift under Friction Sled Cycles
Friction sled cycles strip migratory slip agents, elevating polar surface energy while generating micro-roughness that causes severe specular gloss drift.
Non-Migratory Slip Agents
Static Chemistry
Slippage control in packaging films and extrusion-coated board prevents material blocks and ensures smooth transport through packaging machinery. The use of non-migratory slip agents provides a stable coefficient of friction by using high molecular weight additives that remain locked within the polymer matrix. These agents do not move to the surface of the film over time.
Coefficient Stability
Traditional slip additives like erucamide tend to travel to the surface of the film, where they can build up on sealing jaws or contaminate food products. This surface build-up can also interfere with the adhesion of printing inks and laminating adhesives. In contrast, these non-migratory additives stay distributed throughout the polymer layer, providing consistent sliding properties without affecting printability.
This stability is critical for long-term storage of treated films.
Process Protection
Evaluation of these additives involves measuring the coefficient of friction under different temperatures and after long periods of storage. This ensures that the material can be run on high-speed form-fill-seal machines without the risk of scuffing or jammed rolls. Packaging manufacturers use these stable compounds to guarantee consistent performance on both the printing press and the packaging line.
Using these agents prevents the decrease in surface energy that often occurs when migratory additives gather on the film surface, allowing for stronger heat seals and better ink adhesion in demanding packaging applications.