Polyurethane Soft Touch Film Selection for Folding Cartons
Polyurethane soft-touch films provide superior scratch resistance and score fold integrity compared to BOPP but require higher temperature control and lower web yields.
Aliphatic TPU
Polymer Chemistry
Ultraviolet stable thermoplastic polyurethane resins provide a flexible and transparent protective layer for high value printed substrates and flexible packaging. Using aliphatic tpu ensures that the laminate remains clear over time even when exposed to intense sunlight or artificial lighting. Unlike aromatic variants that contain phenyl groups which degrade into yellow components, these molecules rely on saturated carbon chains to maintain their chemical bond strength.
Material Durability
Chemical resistance and puncture strength characterize the performance of these films in demanding logistics environments. While standard adhesives might fail under extreme temperature fluctuations, aliphatic tpu maintains its elasticity and bonding properties from freezing conditions to high heat. The material functions as a high performance barrier against moisture and oils, which protects the underlying print and paper fibres from environmental degradation.
Its high abrasion resistance makes it a preferred choice for book covers and luxury packaging that undergoes frequent handling.
Conversion Utility
Processing these resins requires specific temperature profiles to achieve the desired flow and adhesion to the substrate. Since aliphatic tpu has a lower refractive index than many competing polymers, it enhances the colour depth of the printed graphics beneath it. Converters typically apply the material using extrusion coating or as a pre formed film in a thermal lamination process.
The resulting finish provides a soft touch texture that does not compromise the recyclability of the paper carrier when used in specific concentrations. Bonding occurs at the molecular level, creating a permanent union that resists delamination during die cutting or folding. This chemical bond ensures that the protective properties of the film remain intact throughout the entire lifecycle of the package.