Quantifying Surface Energy Values on Polyolefin Packaging Materials
Polyolefin surface energy quantification relies on standardized liquid titration or goniometry to secure ink adhesion and lamination bond strength across runs.
Gravure Solvent Inks
Print Quality
High-speed liquid coatings applied by engraved cylinders are widely used in flexible packaging for their high color density and rapid drying times. Using gravure solvent inks ensures that fine text and dense tones print clearly on non-porous polymer films. The low viscosity of the formulation allows it to flow easily into the cells of the gravure cylinder and transfer cleanly to the moving substrate.
Formulation Chemistry
Organic compounds like ethyl acetate and alcohols are used to dissolve the pigments and resins to maintain a low working viscosity. These volatile chemicals evaporate quickly on the press, allowing the printed web to move through subsequent stations without smearing. The resin binders provide excellent adhesion to various plastic surfaces and resistance to scratching during post-printing processes.
Drying Mechanism
High-velocity air dryers remove the volatile organic compounds from the wet ink film to prevent solvent retention in the finished roll. Solvent retention can lead to odor problems in food packaging or cause block-resistance issues where the rolled film sticks to itself in storage. Recovery systems are often integrated with the printing press to capture the evaporated solvents and prevent environmental release.
In high-volume plants, automated ventilation controls adjust the air volume according to web speed to maintain solvent concentration levels below lower explosive limits.