Holst Centre - Page 5

The Holst Center has developed and produced a new flexible OLED that will be used on the back-side of a racecar rear-view mirror. This the first application of a "flexible OLED on foil", according to Holst. They have used Holst's encapsulation technology and Araldite composite materials of Huntsman Advanced Materials. In fact the OLED itself displays the logo Araldite. The OLED is a white "signage device" - it cannot change the display, and the logo is constructed by patterned deposition of light emitting polymer.

The car is the ORECA01 car from French racing team Oreca and they will will be using the mirror in the 24 hours Le Mans race (June 12-13). 12 hour of this race is in the dark, and people will be able to see the writing...

InnoPhysics has performed successful feasibility studies at the Holst Centre, and now is ready to go to market with its proprietary Digital-on-Demand PlasmaPrint hardware solution. They say that their technology enables software patterned surface functionalization, etching and deposition of functional coatings on thin (plastic) substrates.

Plasma-printed OLED lighting test structures

The proprietary InnoPhysics technology solution operates on a large variety of plastic substrates in ambient conditions, at room temperature and it provides flexibility in patterning, i.e. mask-less. As part of the go-to-market strategy, InnoPhysics is developing a PlasmaPrint toolkit integratable with existing table-top R&D print platforms.

The Holst Centre and NeoDec will partner on metallic inks for flexible electronics. NeoDec's conductive ink technology is a complementary technology to the competences of Holst Centre and its industrial
partners and opens new routes to enable roll-to-roll manufacturing of flexible electronic devices such as OLED lighting foils. The partnership will initially run for 2 years, and NeoDec's technology will be further developed within the Holst Centre.

Printed structures from the Holst Centre

The Holst Centre has released a new proprietary roll-to-roll (R2R) sintering platform for fast and low-temperature curing of printed conductive structures. The center is progressing towards a complete tool set for R2R manufacturing and can be used for plastic electronics such as flexible OLEDs, organic PV solar cells and more. Holst' line now includes printing, coating, drying and lamination stages in addition to the new sintering unit. A vacuum deposition stage is currently in development.

Screen printed structures on foil photo

High web speeds and low temperatures are key elements for R2R manufacturing of plastic electronics. The sintering platform uses a new photonic sintering process, developed by Holst Centre, which heats only the printed target material rather than the whole carrier substrate. The tool can sinter printed conductive structures in less than a second, which is already enabling a fast throughput speed of over 5 meters/minute. It also works at significantly lower temperatures than traditional sintering techniques, preventing distortion of the carrier substrates and reducing energy costs.

Agfa, Philips and the Holst Center are showing a large-area (12x12cm2) flexible OLED - without ITO as transparent electrode, and with printed shunting lines. This means that costly materials and lithography processes are not needed, and the OLEDs are much cheaper.

Flexible OLED lighting prototype with no ITO

Up till now, ITO was needed as supporting layer for the PEDOT/PSS* anode layer with lower conductivity. Thanks to Agfa’s high-conductive transparent polymer OrgaconTM, a PEDOT/PSS-based solution with six orders better conductivity than its predecessor, the use of ITO can now be avoided. Proof is the latest OLED lighting demonstrator of Holst Centre’s shared programs: a homogeneous white OLED tile of 12x12cm2 without the use of ITO.

Novaled and Holst Centre have decided to collaborate under a joint development agreement. They will work on using the Holst centre's Organic TFT tech and Novaled's OLED dopants:

Novaled's doping technology contributes to very high power efficiencies and long lifetimes in OLEDs by improving charge carrier injection and transport in the organic layers. Novaled has shown that these effects are also relevant for organic TFT as the carrier injection from drain and source into the organic material has a major influence on the device performance. Novaled currently develops dopant and host materials which can be processed both in vacuum and in solution.

Europe joins forces in the form of a new integrated R&D project that aims to research and develop light emitting foils based on OLED technology. A group of 14 companies, research institutes and universities, leading in the fields of printing and electronics has formed the consortium of Fast2Light and will align efforts to demonstrate that high quality and cost-efficient lighting foils are the future for lighting and signage applications.

"The steady progress of light-emitting materials in recent years, identify OLED technology as the next solid-state, large-area light source. Within this project consortium we are able to combine European leading partners in the fields of printing, electronics and roll-to-roll processing and to create critical mass for the development of OLED lighting foils. Fast2light aims to set in place the manufacturing platforms so as to accelerate the introduction of lighting foils into the market when the light-emitting polymers meet the product specs" said Mary Kilitziraki of Holst Centre, project manager of Fast2Light.

The project, partially funded under European Union’s 7th Framework program as part of the ICT (Organic and large area electronics, visualisation and display systems) priority, will address all layers that are part of a lighting foil. It will start with the plastic substrate, and introduce high-throughput deposition and patterning methods for all of the materials necessary to fabricate the final lighting foil. Ultimately, the project will demonstrate a 30cm x 30cm, high quality lighting foil, manufactured with new optimised, disruptive R2R processes. While the project will focus on polymers, the platforms developed will be fully compatible with SMOLEDs.