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 Diamond watch components
18.06.2018 | Schweizerischer Nationalfonds SNF

nachricht Quick and safe laser joining of steel-aluminum mixed connections
05.06.2018 | Laser Zentrum Hannover e.V.

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

Im Focus: World record: Fastest 3-D tomographic images at BESSY II

The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.

Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...

Im Focus: A molecular switch may serve as new target point for cancer and diabetes therapies

If certain signaling cascades are misregulated, diseases like cancer, obesity and diabetes may occur. A mechanism recently discovered by scientists at the Leibniz- Forschungsinstitut für Molekulare Pharmakologie (FMP) in Berlin and at the University of Geneva has a crucial influence on such signaling cascades and may be an important key for the future development of therapies against these diseases. The results of the study have just been published in the prestigious scientific journal 'Molecular Cell'.

Cell growth and cell differentiation as well as the release and efficacy of hormones such as insulin depend on the presence of lipids. Lipids are small...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

NRL's sun imaging telescopes fly on NASA Parker Solar Probe

13.08.2018 | Physics and Astronomy

UT-ORNL team makes first particle accelerator beam measurement in six dimensions

13.08.2018 | Physics and Astronomy

ASU astrophysicist helps discover that ultrahot planets have starlike atmospheres

13.08.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>