Digital Print's Wider Range

With the 2008 trade show season about to commence, printers interested in digital press equipment eagerly await the On Demand Conference & Expo (March 3-6, Boston) and drupa 2008 (May 29 – June 11, Dusseldorf). This drupa marks the fourth quadrennial event in which digital printing has been one of the major technologies on show. From one drupa to the next, we have seen significant developments that move forward both the state of the art of digital printing and customer's perceptions of what digital printing can do for them.

At drupa 1995, despite the tremendous innovations of both Indigo and Xeikon, digital printing for most printers was not a relevant technology and few printers took it seriously. In fact they took the concept of DI (direct imaging) offset printing with on-press CTP far more seriously at that time.

At drupa 2000, the arrival of the Xerox DocuColor 2000 series changed the perception of digital printing in the eyes of many printers and really started the move of digital printing into many offset houses. At drupa 2004, printers concerns about quality were largely dissipated with the quality being shown from HP Indigo, Kodak NexPress and Xerox iGen3. Océ also indicated its way to the future with its Variostream 9210 monochrome printer as its future platform to grow into a 4-color continuous feed printer.

In the inkjet area, the speed of the Kodak Versamark indicated likely developments for the future. Agfa's :Dotrix continuous feed inkjet printer showed the opportunity of moving inkjet into the flexo markets previously not covered by digital printing. It also showed how UV curable inks could open up new opportunities for inkjet printing. Perhaps the most interesting product however at drupa 2004 that showed how the technology could change the future market was the Riso HC5000 inkjet printer. This amazing product was the fastest sheetfed color digital printer at the show as well as being one of the cheapest.

It has already been said that drupa 2008 will be the “inkjet drupa.” Up to now, inkjet printing has had a major impact in the wide and super-wide format areas taking work predominantly from screen-printing. In this market companies like VUTEk, HP Scitex, Nur, Inca and many others have changed the face of display, poster, billboard and point-of-sale printing. In this we have seen a whole new range of printed products that previously were not available, such as building and bus wraps.

This form of digital printing using inkjet has largely taken over in the markets in which it is used. There will still be more developments of this at drupa with faster and higher quality printers, but also we will see major ecological pressures in this area as aqueous, UV curable and other eco-friendly inks take a share of the market from solvent inks. We can also expect further developments of this technology into the packaging area with equipment for printed corrugated and folding cartons at, or close to, the manufacturing locations for the products they are to package.

The key developments at drupa 2008 will be in the up-to-19.7´´ wide digital presses where the battle will be between inkjet and xerographic technologies. (I include HP Indigo's presses in the xerographic area as their Electrophotography technology is a form of xerography and their Electroink is liquid toner).

In the sheetfed digital printing area that will predominantly stay xerographic, we will get digital presses going a little faster than today. I would, however, be surprised if any sheetfed color printer exceeds a speed of 150 8.5×11´´ ppm. In this market, the battle is much more about quality than speed and having more than four colors may prove to be a key-selling message—providing it does not impact too much on speed. Somewhat surprisingly, I don't expect to see a 20´´-wide sheetfed digital color press.

The key battles in this area will be in quality and cost. In the cost area we will see even more aggressive competition in the sub $74,000 market. Here the speed level for this price should get up 70 8.5×11´´ ppm or more. I also expect to see HP introduce its Edgeline inkjet technology into this area. I would also not be surprised to see a higher quality version of the Riso inkjet than the current HC5500 model.

The main focus for inkjet technology will be in the continuous-feed color presses. At the last drupa, we only had three products in this area, the Kodak Versamark, the Miyakoshi and the Agfa :Dotrix. This drupa there will be many more. We already have the Screen Truepress Jet520 and the InfoPrint 5000, which use the same engine: Seiko Epson print heads and aqueous inks. A single engine will produce around 450 8.5×11´´ color ppm.

The reason we are now starting to see high-speed inkjet printers is due to ongoing developments in printhead technology that allow manufacturers to create full machine-width print arrays that allow for the ink to be laid down in one pass of the paper under the head. In most wide format and desktop inkjet printers, the print head has to make multiple passes over the paper to lay down the ink. At last September's LabelExpo exhibition in Brussels, there were a number of new inkjet presses that show how future inkjet presses may look. One of these is the Nilpeter Caslon press co-developed with FFEI. The 4-color system features a single-pass print engine.

In this, the web substrate is moved from left to right over the curved print platen under the four print assemblies (shown in sidebar, lower left). Each assembly in the case of this 13´´ wide printer has five Xaar 1001 printheads that are physically and optically aligned (stitched) to give a full 13´´ wide print array with a resolution of 360 dpi with eight grey levels. The web speed at this resolution is 82 fpm. It can run at up to 164 fpm with four grey levels which give a lower quality image. In terms of 8.5×11´´ images, 82 fpm is the equivalent of 115 8.5×11´´ images per minute.

The ink in this print engine is UV curable ink and the curing takes place between each color and after all the colors have been printed. UV curable ink allows inkjet printing on a wide range of substrates and also is ecologically friendly. Currently, the Caslon print engine is offered with imaging widths of 13´´ and 16.5´´. In this latter case, the print array has seven printheads stitched together. Later there are plans to produce Caslon print engines using an array of eight stitched printheads per color. All of these would have the same imaging speed of moving the web at 82 fpm, however in terms of 8.5×11´´ ppm this would increase the speed to around 160 8.5×11´´ ppm.

The speed of inkjet printers is, therefore, based on the linear imaging speed of the printhead. The speed of the head is based upon the technology used. Currently the fastest printheads are the continuous inkjet technology heads used in the Kodak Versamark V-Series product range. These heads, however, do not produce as good a quality as drop on demand (DOD) piezo printheads. In the piezo DOD area there are a number of different printhead approaches and this affects the quality of printed image and speed of operation of these heads.

The fastest DOD heads are the Seiko Epson and Panasonic heads but these only produce a binary (1 grey level) 600 dpi ink dot. The heads also use a piezo thin film actuator technology that limits the printer to using aqueous inks. This also limits the type of substrates that can be used. Most DOD printheads used with solvent inks for the super-wide format printers and for the presses using UV curable inks use a shear mode technology that allows either a binary (1 bit) or a variable drop size (multiple overlapping drops), but don't run as fast as the thin film heads. The basics from this: the new inkjet presses that will be seen at drupa will either have a linear imaging speed of around 82 fpm with excellent quality, or speeds in excess of 164 fpm with lower quality and limitations on substrates that can be used.

These new inkjet print engines will be available in most cases as standalone printers in either single- or dual-engine mode that allows for single-pass duplex printing. There will, however, be the start of the market for hybrid systems where the inkjet print engine will be added to an existing press or finishing system. We saw the first such product at Ipex 2006, when Muller Martini and Kodak worked together to add Versamark printheads onto a Muller Martini offset press. In this situation, the offset press would print the static data and the inkjet engine would add the changeable data.

The Agfa :Dotrix print engine had also been used to create a hybrid press when it was added to a Mark Andy label press. This project never succeeded and was dropped. At LabelExpo, Nilpeter introduced a hybrid label press by adding the Caslon inkjet print engine to a Nilpeter label press. The development of inkjet print engines such as Caslon, with its range of imaging widths, is likely to start up a new market in hybrid presses when added to existing presses or even to print finishing systems.

In terms of new inkjet presses that I expect to see at drupa, almost all of these will use DOD rather than continuous inkjet technology. Kodak has a new development under way called Stream (see sidebar) that is expected to move continuous inkjet to a new level of quality, flexibility and speed. It will be shown as a technology demonstration at drupa, running at 500 fpm on a concept digital press, but won't be brought to market until 2010. It features high-speed MEMS (microelectromechanical systems) print heads and a drop delivery system, although details about drop size and resolution are being held close to the vest at this point. CTO Bill Lloyd says that the interaction of pigmented inks and media—including glossy coated paper—is key to output quality, which Kodak says will “move inkjet into the offset class.” In the DOD area, the fastest product will probably be running at a speed in excess of 1,000 8.5×11´´ ppm in simplex mode. This can be seen with the new Océ JetStream 1100/2200 and Kodak Versamark VL2000 products. The quality of such a press, however, will be higher than that of the Versamark.

Also in the DOD inkjet area, thermal technology is used by Canon, HP and Lexmark. This is a cheaper technology than piezo DOD inkjet but it is not as flexible. The technology of thermal inkjet is for the ink to be heated and as it boils it is expelled from the printhead. This technology can only use aqueous inks. The technology allows for high resolutions and the latest printheads allow for a large number of nozzles in the head. Unlike piezo-based DOD printers the printheads have a limited lifespan and need regular replacement.

For the printer market, the new HP Edgeline printheads are likely to have a major impact on the office and possibly graphic arts markets. The first products using these heads are a 6-color photo printer with three printheads and a 4-color printer with four printheads with a speed around 60 8.5×11´´ ppm. Potentially, HP can build a range of products using Edgeline printheads—and these could be of a wide format for display printing or be built into wide print array for either sheet or continuous feed printers. I would expect to see some HP Edgeline developments at drupa.

From the above outline of developments in printers, one might imagine that there are only future developments using inkjet technology. This, however, is not the case and there will be a large number of new products using xerographic-based technology. At present, in the “light production” color market of products running up to 70 8.5×11´´ ppm, this is currently an almost 100% xerographic market. Only HP and Riso have inkjet products in this area. This is the area of the market that in the past two years has exploded with huge sales. It is where the entry-level products for digital printing will be found for printers still to enter the digital market. This area of the market is very competitive with products from Xerox, Ricoh, Konica Minolta, Canon and HP. Expect a range of new products in this area that offer higher speeds, greater functionality and better quality. With the exception of HP and possibly Riso, this will remain predominantly a xerographic area.

In the production color area again, I believe this will remain a xerographic area. In the speed area of 70 ppm to 200 ppm (8.5×11´´), where offset equivalent quality is the primary requirement, xerography will continue to produce a higher quality than inkjet printing. I would expect that in the sheetfed area the fastest products will be approaching 150 ppm. In the offset-quality continuous feed market, I expect to see products approaching 200 ppm. These engines are not imaging any faster than the sheetfed engines; in fact, they are slower but use two print engines printing both sides of the web concurrently.

Also, the toner-based engines from Xeikon and Océ print a 19.7´´ wide web, thus printing more pages across the web. There will be faster xerographic printers there, but they'll be printing “business color.” Ricoh is expanding into the production print arena with the Pro brand of 90-ppm color devices based on a Hitachi solution acquired in 2004. In addition to its InfoPrint joint venture with IBM, Ricoh—exhibiting at drupa for the first time—will bring its new Pro C900 and C900s, which output at 1200-dpi resolution on thick paper (up to 300 gsm) and even coated stock, supporting formats up to 12.6×17.7´´. Featuring EFI Fiery print/RIP servers, both models use pulverized toner for a wider color gamut and improved fusibility.

I expect the highlight of Xerox's 100,000-sq.ft. stand to be the new continuous-feed color press, the 490/980 launched in Japan last October. This device produces a quality (600-dpi resolution) similar to that of the high-speed DOD inkjet printers and is suited for transactional (transpromo), direct mail and newspaper applications. The 490/980 maintains top speed when printing full color or black and white, regardless of the number of colors used or the weight of the paper. It prints 226 fpm or 493 images per minute two-up, simplex on 8.5×11´´ paper, and 986 images per minute when in the duplex configuration.

This product sets a new price level for xerographic printing—at a speed approaching 1,000 ppm and at a lower print cost than other xerographic color printers. This will challenge the new high-speed inkjet printers in opening up new markets for digital printing. The system will be available for order taking in Europe during the first half of 2008, followed by North America, and is anticipated to have a U.S. price of approximately $1.8 million per engine.

Xerox has even faster technology, but it's monochrome for now. Its new 650/1300 can print up to 1,308 duplex 8.5×11´´ images per minute. The system uses dry toner, xerographic imaging and flash fusing—a unique process that does not use heat or pressure or make contact with the paper. “The flash-fusing technology provides ample flexibility for printing on different media,” said Charles Inches, production head for Corner Bank, Switzerland, at last month's pre-drupa press briefing.

So, will drupa 2008 be the inkjet drupa? Well the answer to that is both yes and no. In terms of yes, it will be the arrival of a large number of new inkjet printing solutions that will develop and expand their role in the market over the next few years.

They will not, at this time, challenge the existence of offset or flexo printing—the printheads are not good enough in terms of quality or speed to challenge conventional printing. In the quality area, inkjet as yet will not be competing against xerographic approaches for offset and “better-than” offset quality applications. It will expand its role in the wide and super-wide format applications area and will open new markets for on-demand packaging applications. In the new area of high-speed transactional business color, we will see inkjet and xerography competing against each other.

The main message of drupa will be that inkjet will have arrived as a technology for opening up many new applications for digital printing, particularly in the industrial printing area. Perhaps drupa 2012 will be the real inkjet drupa.