At the OLED Korea conference, both Merck and Sumitomo detailed their latest OLED inkjet material performance.
UBI Research estimates that AMOLED shipments reached 440 million units in 2017 (up 13.6% from 2016), with revenues reaching $27.1 billion (up 62.3% from 2016). Only yesterday did DSCC release its own estimates of $23.2 billion in revenues for the AMOLED market in 2017.
The AMOLED market is expected to grow at a CAGR of 17.5% to reach almost a billion units in 2022. Revenues will grow faster at 22% and reach $80.5 billion in 2022.
Many OLED producers believe that Ink-Jet printing of OLED emissive materials is the best way to achieve lower-cost OLED TV production, and to enable OLEDs to compete in the medium part of the TV market. Ink-Jet printing is an efficient process (less material waste compared to evaporation) and it can be very quick as well. The main drawbacks of inkjet are the limited resolution and the need for soluble emissive materials which are less efficient compared to evaporation ones.
A Kateeva OLED ink-jet printing system
These challenges are being overcome, and it seems that at least four groups (in Korea, Japan and China) are charging forward towards mass production of ink-jet printed OLEDs. Ink-jet printer makers and soluble material suppliers are also optimistic ink-jet printing commercialization will soon be here as the material performance gap is diminishing.
In 2015 the EU launched a 3-year €4 million OLED lighting project, the LEO project (Low-cost / energy Efficient OLEDs) that had an aim to develop efficient and cost-effective bendable OLED lighting technologies. The project consortium included Osram, and Cynora.
A month before the project officially ends, the partners updated on their progress. For this project, the partners develops several technologies, including low-cost metal foils integrating OLED anodes and possibly backside monitoring printed circuits, smart OLED top-electrode architectures and light out-coupling solutions and a novel thin film top-encapsulation strategies. These technologies together increased the light output by 50% while providing better surface scratch resistance.
The SOLEDLIGHT (Solution Processed OLEDs for Lighting) project was launched in 2015 by a European consortium with an aim to develop cost efficient, roll-to roll (R2R) solution processed OLEDs, including their integration in prototype multiple-panel OLED lighting systems and luminaires.
The SOLEDLIGHT consortium (which is coordinated by the University of Valencia and includes OSRAM and Solvay) reported that it managed to develop multi-layer R2R solution processed OLEDs that achieved a power efficiency of 20 lm/W. This is still not up to par with evaporation-based OLEDs, but the project partners aim to achieve 100 lm/W (and 15,000 hours) by the end of 2017.
LG Display currently produces all its OLED TV panels using an evaporation (VTE) process. Market research company DSCC says that ink-jet printing is more efficient than current VTE processes as it will result in simpler displays (no need for color filters, for example, as used by LG's current WRGB displays). Ink-Jet printing will also enjoy lower depreciation costs and lower indirect expenses such as water and electricity.
DSCC estimates that an ink-jet printed 55" OLED TV panel will cost 17% less to produce compared to a VTE produced panel. An ink-jet printed panel will theoretically be significantly brighter (as the color filters absorb a large portion of the light), however solution-based OLED materials have traditionally lagged behind evaporation ones (Merck though says that the latest soluble materials are on-par with evaporation ones).
Sumitomo Chemical acquired CDT back in 2007, and since then the Japanese company has been developing it's PLED (polymer-based OLED) materials and technologies. While initially Sumitomo aimed to produce materials for displays, in recent years it has focused mostly on OLED lighting materials and even panel production.
A noted exception was Panasonic's OLED TV development project which used printing technologies and Sumitomo's PLED materials. But Panasonic terminated this project in 2013. We speculated that JOLED, which is based on Panasonic's technology (and other technologies as well), uses PLED materials in its prototypes, but we were not sure.
Last month JOLED announced that it started to sample 21.6" 4K OLED monitors. JOLED plans to develop these OLED monitors for medical applications - it will produce these in low volume at its current 4.5-Gen pilot production line, and will start mass production in 2019.
JOLED's CEO, Nobuhiro Higashiiriki, said in a conference that these first samples were shipped to Sony, which may become JOLED's first customer. JOLED says that the company managed to achieve a high quality and long lifetime, which was a challenge due to the printing process used.
Researchers at the University of California, Santa Barbara and the Dow Chemical Company have chosen a bottom-up approach to patterning emissive polymers, aiming to solve some of the problems that plague Solution-based protocols for OLED manufacture.
The team started with a layer of indium tin oxide and used light-activated chemistry to pinpoint specific locations on the surface for polymer growth. Key to the success of this approach are designer iridium photocatalysts that serve two roles: First, as the catalyst to build the emissive brush polymers, and then as a necessary dopant for the resulting OLED arrays.
In February 2017 BOE Display announced that will establish a new R&D OLED TV production line in Hefei. According to Digitimes, BOE Display is intending to use an inkjet printing process in this line, and the company already placed an order for an inkjet deposition system from Kateeva last month. BOE will use the systems to produce 55" OLED TVs.
In February BOE announced that the new line will cost 1 billion CNY (around $145 million USD). BOE will invest 80% of the funds, with the rest provided by the Hefei government. Digitimes now states that the new line will only cost 600 million CNY - so it may be that the inkjet printing line is an addition to the 1 billion CNY line (which in that case, will probably be based on an evaporation process).