Evaluating Surface Energy Decay in Thermal Polyurethane Film Lamination
Evaluating surface energy decay in thermal TPU lamination requires measuring polar force components to ensure bond strength before heat and pressure passes.
Anti Setoff Powder
Industrial Separator
Granular starch or silica particles applied to printed sheets prevent the wet ink of one sheet from transferring to the underside of the next sheet in the delivery pile. The use of anti setoff powder creates a physical gap between the stacked paper substrates immediately after they leave the printing press. This separation ensures that the ink dries without smudging or sticking.
Action Mechanism
Dry spraying nozzles distribute these micro-fine particles across the freshly printed surface of the board or paper. These particles act as microscopic pillars that bear the weight of the heavy paper stack, which protects the unoxidized ink layer from pressure-induced contact with the adjacent sheet. The choice of particle size corresponds directly to the thickness of the ink film and the basis weight of the paperboard.
Operational Hazard
Excess accumulation of these granular materials can interfere with subsequent converting processes like lamination, UV coating, or foil stamping. These particles create surface roughness that prevents adhesive resins from achieving full wet-out on the printed sheet, which leads to weak heat seals or bubbling in laminates. Cleaning the sheets or using specialty low-powder ink formulations minimizes these finishing challenges on high-speed packaging lines.
Furthermore, airborne dust from heavy application can settle on machine rollers and cause premature wear or irregular pressure during folding.