In 2012 Xeikon announced that it had acquired a research company active in liquid toner electrophotography. Its intellectual property provided the foundation upon which Xeikon is developing a liquid toner based printer. The technology was presented publicly for the first time at drupa 2012 with a single station unit shown behind glass printing at 60 meters per minute as a technology demonstration, but without showing or handing out print samples.
Though interesting, this technology demonstration did not fully convey the potential of the technology. Now Xeikon has made public some more details on the technology and its planned first product implementation, which show how the company intends to challenge inkjet technologies at higher volumes.
According to Xeikon, Trillium is targeted at high quality print applications, similar to the current 8000 Series dry toner printers, but designed for higher print volumes and with an improved cost structure that will challenge not only inkjet, but also provide an improved break-even point versus offset. In short, Trillium is an extension of the Xeikon product portfolio of document printers. The company plans to position the technology for demanding high coverage colour applications that inkjet cannot reach from a quality or cost perspective.
The base imaging process is liquid toner electrophotography. The toner particles used are about 2-3 microns in size, instead of about 7 micron as in Xeikon’s current dry toner products. This should allow very high resolution and a thin colorant layer on the substrate. The liquid carrier traps the small particles without letting them become airborne, allowing very precise handling of these fine particles. A liquid paraffin type imaging oil is used to transport and trap the pigment during image transfer. Xeikon stresses that there are three transfer steps from a metering roller to the OPC drum (Organic Photo Conductor) to the intermediate roller to the substrate. Very small gaps between cylinders, termed “micro gaps,” allow precise transfer from drum to drum. During the transfer most of the imaging liquid is retained while letting the toner pass. Finally the toner with some residual imaging oil is transferred to the paper, while the rest of the imaging oil is recycled.
Other parts of the imaging process builds upon tried and tested Xeikon imaging technology. The printer will use Xeikon’s own LED-imaging technology, resulting in the same resolution of 1,200 dpi. The process uses a seamless OPC drum as in current products, but they are bigger to allow for faster speeds and heavier workloads. Fusing is done with heat and pressure in a final fusing unit.
Trillium today is a technology, not a product. Xeikon, however, has given some hints about what a future product will look like. The proposed product consists of two vertical towers; one for each side of the paper, with a turn bar in between the towers. The design is larger than the current duplex tower models, but is still compact through the use of vertical towers. Xeikon targets roughly 11 meters (36 feet) as the length for the printer. The first model will have a speed of 60 meters per minute (approximately 200 feet per minute). Doubling the speed in a future model is in sight. With a planned imaging width of around 500 mm/19.8” (likely to be the same as the 504 mm imaging width in the current Xeikon models) this would roughly translate into 800 images per minute for a duplex printer. The paper range is targeted for 60 to 250 gsm.