Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New technology for ultra-smooth polymer films

28.06.2018

The Fraunhofer FEP has succeeded in developing a new technology for the production of ultra-smooth polymer films as part of the "OptiPerm" project. This project received funding from the European Union and the Saxony State Ministry of Economics, Labor and Transport (grant agreement no. 3000651169). The technology, which was previously demonstrated on samples in A4 format, has now been successfully transferred to a roll-to-roll process with even higher surface quality. These results were presented for the first time at the AIMCAL conference in Munich, Germany in June 2018 by Dr. Steffen Günther.

Smooth surfaces with low defect densities are of great importance for many application areas, be they decoratively coated vehicle bodies, high-gloss and dirt-resistant furniture, or ultra-smooth metal and plastic films that serve as substrates for high-tech industries. Particularly in latter case, subsequent finishing steps can only exhibit their full potential if the surface quality of the substrate is also at a very high level.


Flexible film substrate of 1.25 meter width at the roll-to-roll coating line „atmoFlex 1250”

© Fraunfofer FEP | Picture in printable resolution: www.fep.fraunhofer.de/press

For example, films for the encapsulation of electronic components need thin permeation barrier layers made by a vacuum coating process that prevent against penetration of oxygen and moisture. Defects on the substrate surface would compromise these thin coatings.

The deposition of active electronic layers, for example for OLEDs or touch screens, requires ultra-smooth surfaces to ensure reliably capabilities such as light emission and conductivity over large-areas.

Scientists at Fraunhofer FEP have now developed a new method for creating ultra-smooth surfaces – dubbed the smoothing-film approach. “This innovative process does not require any special processing environment and could therefore also be used under standard factory conditions,” explains Dr. Steffen Günther, Project Manager at the Fraunhofer FEP. “Expensive clean rooms are not required for this process.”

With this new approach, a wet coating is first applied to a flexible substrate. Immediately afterwards, the coating is covered while still wet with a second film, the smoothing film. Subsequently, the wet coating is cross-linked through the smoothing film by an energetic drying process. An electron beam is used therefore at Fraunhofer FEP due to its high performance regarding cross-linking ratio.

The smoothing film may be lifted off directly after cross-linking or stay on top the coating as a protection until the next downstream processes take place. In order to reduce the costs for the smoothing films, their reusability was examined. The scientists were able to show that even after reusing the smoothing film ten times, no increase in defect density or decrease of surface quality was observed.

The process was initially carried out and evaluated on samples in A4 format. Subsequent is has been transferred to the roll-to-roll coating line “atmoFlex 1250”. This plant was built by the mechanical engineering company 3D-Micromac AG and offers the possibility to coat flexible films of 1.25 meter width in roll-to-roll process at Fraunhofer FEP. The results of the process transfer to roll-to-roll technology even exceeded the expectations by far. Not only was the reproduction of the new smoothing-film approach successful. The test results of the roll-to-roll processed substrates even outperformed those from the A4 samples by a factor of four.

The defect density determined using white-light interferometry was approx. 1%. This corresponds to the defect density of films planarized in expensive clean-room environments.

These positive results can now build the basis for developing further innovative film products with industrial partners. The scientists are already contemplating ways to further improve the technology and also how to transfer it to other areas of application.

This work was partially supported by the European Union and the German State of Saxony within the project OptiPerm (Grant agreement number: 3000651169). OptiPerm is a joint research project with the industrial partners VON ARDENNE GmbH, 3D-Micromac AG, GfE Fremat GmbH and IOT - Innovative Oberflächentechnologien GmbH to do research into the production of functional films with optimized permeation barrier coatings.

Press contact:

Ms. Annett Arnold

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP
Phone +49 351 2586 333 | presse@fep.fraunhofer.de
Winterbergstraße 28 | 01277 Dresden | Germany | www.fep.fraunhofer.de

Weitere Informationen:

http://s.fhg.de/vJq

Franziska Lehmann | Fraunhofer-Institut für Organische Elektronik, Elektronenstrahl- und Plasmatechnik FEP

More articles from Process Engineering:

nachricht NRL develops laser processing method to increase efficiency of optoelectronic devices
16.04.2019 | Naval Research Laboratory

nachricht Hollow structures in 3D
29.03.2019 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Quantum gas turns supersolid

Researchers led by Francesca Ferlaino from the University of Innsbruck and the Austrian Academy of Sciences report in Physical Review X on the observation of supersolid behavior in dipolar quantum gases of erbium and dysprosium. In the dysprosium gas these properties are unprecedentedly long-lived. This sets the stage for future investigations into the nature of this exotic phase of matter.

Supersolidity is a paradoxical state where the matter is both crystallized and superfluid. Predicted 50 years ago, such a counter-intuitive phase, featuring...

Im Focus: Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter

  • Coolest and smallest star to produce a superflare found
  • Star is a tenth of the radius of our Sun
  • Researchers led by University of Warwick could only see...

Im Focus: Quantum simulation more stable than expected

A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.

Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...

Im Focus: Largest, fastest array of microscopic 'traffic cops' for optical communications

The technology could revolutionize how information travels through data centers and artificial intelligence networks

Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...

Im Focus: A long-distance relationship in femtoseconds

Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.

Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

Fraunhofer FHR at the IEEE Radar Conference 2019 in Boston, USA

09.04.2019 | Event News

 
Latest News

Marine Skin dives deeper for better monitoring

23.04.2019 | Information Technology

Geomagnetic jerks finally reproduced and explained

23.04.2019 | Earth Sciences

Overlooked molecular machine in cell nucleus may hold key to treating aggressive leukemia

23.04.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>