Extrusion Asia Edition 2-2025

49 EXTRUSION & RECYCLING ASIA 2/2025 FILM EXTRUSION “D ue to its properties, MDO-PE lm is an ideal solution when it comes to replace PET in PET-PE laminates, which were used for a variety of exible packaging products as a standard so far”, Elias Mayrhofer, Product Manager at extrusion line manufacturer SML explains. Application areas of MDO-PE lm range from mono-material tubular bags for food packaging to side gusset bags, and from sealed bags to di erent types of pouches. Straight-forward further processing MDO-PE lm manufactured on SML’s latest cast lm lines with integrated MDO unit provide excellent optical, mechanical and barrier properties. The lm can be eas- ily laminated to mono-material structures, for example with CPE sealent lm on a FlexPack line from SML. “Cast MDO-PE lms exhibit excellent printability and have been successfully tested on both Flexographic and Rotogravure printing systems. Metallisation is possible without any complications even with ultra-thin MDO-PE lms”, Elias Mayrhofer states. Wide variety of di erent lm properties The cast MDO technology allows the production of a wide variety of di erent types of MDO-PE lm: Ultra-thin lm down to 15 µm SML cast lm lines are ready to manufacture MDO-PE lm as thin as 15 μm. “It goes without saying, that even at themost ultra-thin lm the process is completely stable. There are no compromises when it comes to performance, functionality and printability,” Elias Mayrhofer says. A market-ready 15 µmMDO-PE lmdeveloped at SML in close cooperation with its polymer supplier and long-term partner Dow Packaging & Specialty Plastics has the following structure (Picture 2): 17 µm lm with an EVOH barrier layer of less than 1 µm This ultra-thin barrier lm was developed by SML in col- laboration with Dow Packaging & Specialty Plastics and EVAL Europe N.V. (a Kuraray company). It comes with this layer distribution (Picture 3): The lm has been extensively tested and is ready for the market. It is characterised by the following barrier proper- ties, given a stretching ratio of 1:5: OTR: 1 – 3 cm³/m²/24hr * * Oxygen transmission rate at 23 °C; 50 % RH, testing method: ASTM F1927-07 WVTR: 5 – 8 g²/m²/24hr * * Water vapour transmission rate at 38 °C; 90 % RH, test- ing method: ASTM F1249-06 Up to 65 µm MDO-PE lm for extended application areas The production of ultra-thin MDO-PE lms of the high- est quality is by no means the only possible application at the latest generation of SML cast lm lines. The achievable thickness range for fully stretched MDO-PE lms goes up to 65 µm which opens up a variety of other possibilities for lm manufacturers. Especially with regard to packaging goods that require higher barrier functions or enhanced mechani- cal properties. Integrated sealing layer: Ready-to-use lm straight from the line A further functional advantage of manufacturing MDO- PE lm in the cast process is the option to directly integrate a sealing layer. This makes it possible to produce a com- pletely ready-to-use lm straight o the line, for example for products such as stand-up pouches. Cast technology for unparalleled lm quality Generally, MDO-PE lms produced in a cast process at- tain an excellent level of transparency. A superior lm qual- ity is reached through optimum atness and the ideal distri- bution of thickness during production. SML Maschinengesellschaft mbH Gewerbepark Ost 32, A-4846 Redlham, Austria www.sml.at Picture 2 Picture 3