The Development And Utilization of 37µm Electric Cross-linked Heat Shrink Film for Banknote Product

Shanghai Sunward Industrial Co., Ltd, after close collaboration with China Banknote Printing and Minting Corporation (CBPMC), has successfully developed 37µm biaxially oriented POF (Polyolefin) electronic cross-linked heat-shrink film for banknote product packaging and now has already launched the mass production of it. The product is currently being utilized by multiple factories in CBPMC Group and it complies with the standards outlined in the "Heat-Shrink Film for Banknote Product Packaging" set by CBPMC.

Cross-linking is a production method that through irradiation it will generate high-energy rays to modify molecule structure and ultimately will enhance product performance significantly. The production of a 37µm thickness cross-linked POF shrink film posed considerable challenges, as it represents the maximum thickness for POF heat-shrink films at present. Generally, the thicker the film, the more difficult it is to achieve the desired physical properties. To enhance various physical properties of the 37µm POF heat-shrink film, a series of measures were taken, including optimizing production processes and formulations. This involved precise control of the extruder unit temperature, mold head temperature, and furnace temperature, as well as accurate control of extrusion speed, traction speed, and winding speed. The optimization of the cross-linking process, appropriate formulation, and precise and stable control of the degree of cross-linking throughout the process were crucial steps to ensure the production of high-quality and stable 37µm electronic cross-linked heat-shrink film. These efforts guarantee the film meets the high standards required by CBPMC, laying a foundation for long-term cooperation.