Production inkjet technology provides the advantages of digital print at volumes and costs closer to offset. Established for quite some time, benefits and applications grow exponentially as advancements in substrates, finishing, and printheads bring the technology to a new level.
A print provider’s decision to invest in new equipment includes a careful look at current and future workloads, ROI, and analysis of the total cost of ownership. Whether a traditional print shop wants to take on digital for the first time, a print for pay hopes to expand into higher volumes, or a print and mail house wants to evaluate production capabilities—inkjet may be the answer.
Production inkjet is currently available as continuous inkjet (CIJ) or drop on demand (DOD). CIJ printheads steadily produce and fire drops of ink. DOD inkjet printheads—whether piezoelectric or thermal—produce drops of ink only as required. Other differentiating factors among inkjet presses include the type of ink set, print width, and media feed options. Here, we look at production inkjet solutions found on the market today, with a specific focus on the technical nuances of each product’s printheads as well as maintenance and operational considerations.
Many factors play into the efficiency and productivity of production inkjet presses. The technology requires proper use and maintenance of printheads. Other elements should be considered, for example, equipment manufacturers promote tested consumables for optimal results. Here, manufacturers offer additional insight into achieving the best-rated lifecycle for their inkjet solutions’ printheads.
"Like all professional printing equipment, the operator’s experience and operating methods impact his or her ability to get the full-rated lifecycle from an inkjet printhead," comments Will Mansfield, director, worldwide marketing, digital printing solutions, Eastman Kodak Company.
Ink composition can also affect printhead life, shares Mansfield. Because of this, the company does not commercialize non-compatible or untested consumables for its printing systems, as they do not produce to Kodak’s quality and reliably standards, he explains.
An inkjet press’ delivery system is extremely important to the life expectancy of a printhead. "The nozzle on a typical four picoliter inkjet printhead is 32 micron in diameter—or roughly half of the width of a human hair," says Tom Leibrandt, print on demand product manager, Screen (USA). Any contamination in the ink train can lead to nozzle failure. The Screen TruePress Jet Series of presses use a factory sealed delivery system to ensure the long life of a printhead.
"Print system ease of use minimizes the burden on the print operator to get the full rated lifecycle from the printheads," suggests Yale Goldis, product manager, Hewlett-Packard (HP) Inkjet High-Speed Production Solutions. He explains that HP printing systems employ automated printhead-servicing routines to ensure optimal printhead health is maintained.
On the Market
The list of production inkjet solutions is continually growing as vendors introduce new products into the space. Look to our Target Chart—featured on page 24 in this issue—for a comprehensive list of production inkjet technologies.
Agfa Graphics’ :Dotrix Modular continuous feed inkjet production press utilizes piezoelectric DOD technology. The press operates with 48 printheads for CMYK and 72 for the CMYK+OV configuration. Native 300 dpi printheads and eight grayscale levels allow an apparent resolution of 900 dpi. Agfa :Dotrix Modular printheads feature a limited lifetime warranty. There is no replacement cost when using Agfa inks. Printheads are operator exchangeable by sliding the cartridge into a slot in the color bar. Agfa’s Kristof Dekeukelaere, :Dotrix sales manager, North America, Agfa Graphics, estimates the printhead changing process takes less than 20 minutes.
Eastman Kodak Company
Kodak offers a portfolio of commercial inkjet products that incorporate CIJ, DOD, as well as Kodak Stream Inkjet Technology (Stream). The amount of printheads and rated lifecycle of the printheads vary by product.
Replacing printheads in a Prosper press, which utilizes Stream technology, is easy and automated, according to Mansfield. The operator presses a button on the Kodak 700 Print Manager and printheads automatically rise up for easy removal.
Fujifilm offers the J Press 720 cut-sheet production inkjet press. The printer touts output with the look and feel of offset and the versatility and job handling of a digital device. It is well suited for traditional commercial printers looking to improve competitiveness for short-run work as well as digital printers that want to offer a wider range of digital print services.
The J Press 720 uses Fujifilm Dimatix’s SAMBA single-pass piezo DOD inkjet printhead technology to achieve a true 1,200x1,200 dpi resolution with four-level grayscale.
HP & Pitney Bowes
After its initial entrance into production inkjet, Hewlett-Packard (HP) continues to offer new products and advancements to its portfolio. HP Inkjet Web Presses use HP Scalable Print Technology (SPT) thermal inkjet heads.
The HP Inkjet Web Press uses HP’s fourth-generation thermal inkjet imaging process. Goldis explains that HP’s thermal inkjet technology features fewer moving parts compared to other inkjet imaging methods.
Printheads found in HP Inkjet Web Presses are comprised of 1,200 nozzles per inch with four nozzles to address each pixel. Visible print defects resulting from nozzle errors can be suppressed or completely eliminated by nozzle redundancy, where the effects of bad nozzles are suppressed by printing with good ones. SPT places multiple, densely packed arrays of nozzles on a printhead along with the integrated electronics to control them.
HP estimates on average a single printhead is replaced about once per shift. When replacing printheads, the pocket aligns the printhead and supplies ink and electrical signals. A manual latch locks the printhead in place.
The HP cost model is not based on a set per-click impression charge. Consumables are sold by the unit and volume in an order-as-needed or a la carte basis.
The Pitney Bowes IntelliJet Printing Systems utilize HP SPT. According to Grant Miller, VP, global strategic product management and North American sales, Pitney Bowes Document Messaging Technologies, SPT brings Pitney Bowes customers the benefits of manufacturing economies of scale.
Miller notes that replacement costs as well as the estimated cost per thousand impressions per printhead is highly dependent on a number of factors. The printhead lifecycle is rated by the volume of ink passing through it.
InfoPrint Solutions, a Ricoh Company, offers the InfoPrint 5000 family of production inkjet presses, which use piezoelectric DOD technology and are designed to support a wide range of applications.
A gamut of speeds are achieved using water-based pigment, dye, MICR, or other fluids on papers such as recycled, ground wood, inkjet treated, and some coated stocks.
Océ, a Canon Group Company, is a known inkjet provider. Its JetStream family of inkjet printers serve the graphic arts, direct mail, transactional and TransPromo applications, and other markets. The devices utilize a piezoelectric DOD process that charges crystals, which then expand and jet ink onto the paper.
RISO, Inc. offers the ComColor series of cut-sheet inkjet devices. Built around the company’s FORCEJET inkjet printing technology, the series is designed to rival toner-based printers in terms of cost, reliability, and environmental soundness.
The ComColor series uses four inline CMYK printheads, which are arranged in parallel to enable the full-color printing of letter-sized paper in a single pass.
Screen (USA) offers its TruePress Jet 520 Series of piezoelectric DOD production inkjet devices. The printheads are proven reliable industry DOD heads from Epson. They are able to print four-level gray that produce smooth transition in tones and finer detail. It also allows the company to take advantage of Screen’s RIPping and screening technology to print high-quality reproductions.
The printheads on the TruePress Jet Series are not considered a consumable item. Therefore, printhead life is not based on impressions.
At last year’s Graph Expo, Screen unveiled the TruePress Jet 520 EX Mono, 520 EX Color, and 520 ZZ.
Xerox’s Production Inkjet Technology uses modular piezoelectric DOD printheads for waterless inks, which are scalable to fit multiple systems. Additional Xerox-patented technology is added to the printheads for nozzle management, tuning, monitoring, thermal control, and auto alignment functions. The technology uses 56 printheads.
The Xerox waterless inks are designed not to dry on nozzles during production. "They are always ready without having to fire spit lines or background patterns to keep them wet, reducing ink and paper waste," explains Kevin Horey, VP, production products, graphic communications, Xerox Corporation.
Automatic real-time jet detection and correction provided the capability to overcome the potential quality impact of missing jets in the print without stopping the printer. "The absence of jet correction means quality has to be compromised, constant visual inspection by an operator is required, or printheads changed more frequently," notes Horey.
Xerox Production Inkjet Technology features robotic cleaning that removes the potential for operator error in the cleaning cycle.
Operators are able to replace printheads in approximately five minutes. Floating printhead technology automatically registers each once installed. Operators can also hot swap printheads by exchanging from the edges of the web that might not be used as often as printheads in the center to help maximize the overall life of the printhead.
In addition to the companies and products mentioned in detail throughout this article, Delphax, Impika, Neryos, and TKS Press also provide or are developing production inkjet solutions. Stay tuned in the coming months as we continue to cover the market leading up to drupa 2012.
The Move to Inkjet
Whatever capacity a print provider is looking to achieve by investing in a inkjet, it is important to consider a variety of elements.
"You always need to look at the total cost of ownership," suggests Agfa’s Dekeukelaere. He notes that the cost of inks and service may be higher than offset, but there are no elements like setup time waste, plate making, and higher operator costs to contend with. "Compared to electrophotography, the big advantage of inkjet is that it’s a non-contact printing process. This means no wear and tear parts, which are typically expensive, compared to piezo inkjet technology," he concludes.
As inkjet technology itself continues to mature—in regards to speeds, feeds, and printhead advancements—supporting technologies, such as finishing and media, are essential to its development and adoption. Visit www.dpsmagazine.com for additional information on inkjet and supporting technologies