Reifenhauser Stakes Claim to 'World's First' 18-Micron MDO Blown Film

Reifenhäuser Blown Film has produced what is says is the world's first machine direction oriented (MDO) PE film of 18 microns thick that meets or exceeds all previous market standards in terms of mechanical properties, appearance and further processing.

The film was produced on Reifenhäuser EVO blown film lines using the patented EVO Ultra Stretch MDO technology and has been developed and tested for practical suitability in collaboration with resin supplier LG Chem and printing specialist BOBST.

Printed samples of the new 18-micron MDO-PE film will be on display at the drupa 2024 trade show in Dusseldorf, May 28-June 7 at the BOBST booth. Mohamed Timol, expert for MDO processes and applications, will be present at the stand as Reifenhäuser’s contact person. 

The new 18-micron film reduces the amount of material used by around 25%, compared to previous film thicknesses of 25 microns. This makes the production of fully recyclable mono-material structures significantly more economical, Reifenhäuser says.

Explains Christoph Lettowsky, senior product manager at Reifenhäuser Blown Film, “Machine builders and manufacturers have been pursuing the same goal for some time: not to use more material in fully recyclable All-PE solutions than in conventional PET-PE laminates. Technically, this is achieved due to the different densities of PET film and MDO-PE film by replacing the 12 μm PET film with a 16 to 17 μm MDO-PE film. With the reduction to 18 μm, we have taken a significant step in this direction — with further downgauging potential for the future.”

Reifenhäuser says this development was made possible by the combination of its MDO Ultra Stretch technology with suitable raw materials. The Ultra Stretch unit is positioned directly in the system’s haul-off, meaning the film is stretched from the first heat. This makes the process particularly reliable: Reifenhäuser has produced the 18-micron MDO-PE film stably and reproducibly over many hours in the test runs.

Despite the low thickness, the film reportedly maintains optical and mechanical properties. With a modulus of elasticity MD exceeding 1,400 MPa and a modulus of elasticity TD exceeding 1,100 MPa, the 18-micron MDO-PE film achieves the current market standard for stretched PE films. With a haze of less than 5%, the 18-micron MDO-PE film performs even better in terms of optical properties than the market standard, which is 6-7%.

The 18-micron MDO-PE film also performed excellently in the converting process and exceeded all expectations of printing specialist BOBST. Davide Rossello, head of competence center and process manager gravure at BOBST says, “The way this extra-thin 18-micron MDO-PE blown film behaves on our printing machines is unique on the market. We have printed the film at high speeds of up to 500 m/min with excellent results in terms of printing quality and register performances. But, even more impressively, we were able to demonstrate the quality of our machine when printing in the BOBST oneECG process, achieving excellent print results at 300 m/min (and above).”