Continuous-feed Inkjet: The Web Paper Challenge

While the market for print has been in decline since 2000, digital printing has continued to grow at double-digit rates, and the new generation of continuous-feed inkjet presses promises to accelerate this growth. At drupa 2012, we saw a host of new entrants, as well as upgrades from the earlier entrants: one drupa visitor reported seeing 18 different inkjet engines. As Figure 1 shows, the speed and productivity of inkjet presses has grown, and inkjet printing has grown apace.

Printers face a number of tradeoffs in selecting presses, ink and paper for production inkjet. This article will explore the challenges and solutions relating to paper in key applications, including transactional and transpromo, book, direct mail and general commercial printing.

IT Strategies estimates that in 2012, 108 billion pages will be printed by production inkjet systems. IT Strategies also projects that this will quadruple by 2015 (see Figure 2 ). Market-Intell estimates that for coated papers this represents something less than 50,000 tons in 2012, and less than 1 percent of the market. For uncoated paper, however, which represents the vast majority of the volume, mainly in transactional print, the volume is in excess of 500,000 tons. This is 6 percent of the uncoated freesheet market, and a much higher share of the transactional print market.

InfoTrends estimates that 57 percent of all inkjet printing is either transactional or transpromo (see Figure 3). Variable data is fundamental to this market and, while quality graphics are important, the print is less demanding than high-quality, four-color offset printing. Ink coverage may be well below 30 percent. The vast majority of all transactional printing is done on uncoated paper, often ordinary offset grades. According to an estimate from one OEM, more than 90 percent of all inkjet is on uncoated paper.

Inkjet inks can be dye-based or pigment-based. In general, pigment inks are more expensive and higher quality, while dye-based inks still produce good color, but colors may be slightly less brilliant and less permanent. Dye-based inks are good for transactional and some direct mail applications, while pigment inks are better for some book applications and general commercial printing where ink coverage is high with four colors.

Water In, Water Out

Both types of inks contain a lot of water, and the water creates a challenge. Dennis Essary, director of digital papers for NewPage Corp., explains: "The water has to go in and leave pigment on the surface, and then the water has to be driven out by heat. This requires a surface that looks smooth, but is actually quite open." This is especially challenging for coated papers, and more so for glossy papers, where coatings are smooth and appear to create a continuous, closed surface.

Paul Bradshaw, senior vice president of publishing papers at Appleton Coated LLC, agrees, and adds that uncoated paper and coated paper present opposite challenges. "Uncoated paper will let the water absorb, but traditional coated won't let the water in. You need to let the water in, but keep pigment on the surface."

There are three approaches to the paper challenge: "ordinary" papers, i.e., untreated offset papers; on-press treatment; and specially treated papers designed for inkjet and produced by the paper mill.

Printers generally prefer to use the same paper for their offset printing as for their digital printing. Offset papers are typically less expensive than specially treated inkjet papers, and the use of offset papers simplifies inventory and merchant supply issues. Moreover, when a job is initially run offset, and then a shorter run reprint is digital, it is important that the paper is a match.

InfoPrint Solutions, initially a joint venture between IBM and Ricoh, launched the InfoPrint 5000 in 2007. Now known as Ricoh Production Print Solutions, the company has worked with virtually every mill at one time or another. Mike Herold, Ricoh's worldwide product manager for inkjet technologies, advises that they have a process to test papers, and "we have a list of more than 300 papers that we support." He adds that with heavy ink coverage, paper selection is more critical, and that "many factors affect document appearance. But, of the variables, paper is 60 percent."

For transactional printing, the vast majority of the paper is uncoated, often MICR/OCR, or MOCR, bond, and the InfoPrint5000 can produce duplex monochrome and full color with on-demand or spot MICR. For coated papers, the InfoPrint 5000 offers an Extended Media Dryer Option, which allows printers to use a wider variety of coated stocks.

Xerox Corp. takes a different approach with its CiPress 325 and CiPress 500 Production Inkjet Systems. The CiPress (pronounced like cypress, the tree) uses waterless inkjet and works with virtually all uncoated papers. Kevin Horey, vice president of production product marketing, explains: "The press uses dye-based polymeric resin in a solid ink. The ink is melted, and jetted directly onto the paper where it dries instantly. This allows crisp dots and sharp edges and, since it sits on top of the paper, permits the use of lighter basis weights." Horey adds that "printers don't have to change their paper supply chain for the CiPress Production Inkjet System because papers used on offset systems work on CiPress."

RR Donnelley's Strategy

One printer, RR Donnelley, has taken the matter into its own hands. Dating back to 1998, when Moore Wallace, later acquired by RR Donnelley, found that customers needed better inkjet quality, they went to HP and licensed inkjet heads. RR Donnelley has been an integrator ever since, and today RR Donnelley has its own ProteusJet Inkjet Press platform. Mary Lee Schneider, president of digital solutions and chief technology officer, explains that they have ProteusJet inkjet presses with both thermal (HP) heads and piezo (Kyocera) heads. She adds, "It's important that Donnelley offer customers a variety of inkjet technologies based on their application. Whether thermal or piezo, all use pigment-based inks for superior color intensity and permanence."

RR Donnelley has tested more than 300 sheets, and has printed on coated and uncoated stocks ranging from 17# to 9-pt. Schneider notes that, "generally, what works on Prosper and HP T400 works on ProteusJet." The ProteusJet platform also uses on-press coatings that enable traditional offset papers.

Finch Paper has worked closely with several OEMs and printers to develop two different inkjet papers, each one optimized to produce the best color quality for the ink system being deployed. Finch dyeJet is specifically engineered for dye-based systems where the colorant has a tendency to flow with the water into the core of the sheet. Pigment inks contain particles designed to stay on the surface and, for those systems, Finch Inkjet Pi is recommended. Phil Hart, director of product marketing, points out that dye-based inks are less expensive and often used for transactional printing, while pigment inks have a larger color gamut and are more often used in direct mail and book applications.

Hart advises that, unlike offset printing, paper is but a small part of the total cost of a production inkjet job. The cost benefits of using optimized pre-treated media are there when ink and energy are included in the equation. "Selling digital requires an educational approach. We help print customers see the entire value chain," he adds.

Domtar's approach is the opposite of Finch's. Ann Rieser, director of market development at Domtar, says that their approach was to create a line of multipurpose papers that work with both dye and pigment systems. "ExpressFlo 92 and VividFlo 96 both have an enhanced surface treatment designed to work with both dye and pigment high-speed inkjet systems, as well as laser and offset printing applications." She adds that "VividFlo has been especially well-received due to enhanced formation, and higher brightness and opacity." Domtar also offers GraphicFlo, a super-smooth, untreated paper with Sheffield Smoothness of 70 that is "laser and inkjet compatible, and designed for use with an in-line treatment."

According to Rieser, VividFlo works well on hybrid systems, since it works well on both offset and inkjet presses. At present the line is targeted to transactional printing, and as such is available exclusively through Domtar's Enterprise Group, which has a long history and strong relationships in the market with forms bond.

Groundwood or mechanical papers also have digital applications. Inger Heinke, vice president of sales at Resolute Forest Products, points out that Resolute offers Ecopaque Jet with ColorPRO Technology for transactional, book and direct mail applications. Ecopaque Jet has higher opacity, and more bulk than woodfree grades, but less brightness. For book and transactional applications, this can be a plus, and for direct mail, more bulk means lower basis weight and less mailing cost. Heinke adds that groundwood paper remedies one of the challenges of inkjet, namely strike through. This is especially true with untreated papers at low basis weights.

As we move from transactional printing to book printing, direct mail and general commercial printing, the amount of color and ink coverage goes up, as does the quality of graphics. This often means coated papers, and HP offers a bonding agent that can be applied on-press to enable good results with ordinary coated offset paper, while Kodak offers an on-press Image Optimizer Station (IOS) that uses a gravure process to coat the paper on both sides. Appleton Coated has worked with HP and developed Utopia Inkjet, while NewPage has worked with Kodak and developed TrueJet. Both work well on HP and Kodak digital presses, as well as other inkjet presses, without a bonding agent or other on-press treatment.

Business Transformations

HP leads the field in pigment-based inkjet, with more than 80 HP inkjet digital web presses (T200, T300, T350 and T400) installed worldwide since 2008. John Meiling, director of large-format printing materials, advises that the initial focus was publishing and direct mail, and that general commercial printing will come next. According to Meiling, "the majority of installs are with offset printers that are looking to augment current printing capacity with digital capability and trying to transform their business."

Gianluigi Rankin, worldwide marketing product manager for HP Graphics Media, explains that virtually all uncoated papers will produce good results on the HP T-series, either papers with ColorPRO Technology or with an on-press bonding agent. Rankin adds that the ColorPRO Technology is more economical and produces better image quality than the bonding agent for medium-to-high ink coverage. Uncoated ColorPRO paper suppliers include Georgia Pacific, International Paper, Resolute Forest Products and Appleton Coated with Utopia Uncoated Inkjet. Coated papers include Appleton Coated Utopia Inkjet and Utopia Book Inkjet in North America. However, for both coated and uncoated, several other mills claim that their papers work as well.

Paul Bradshaw, senior vice president of publishing papers at Appleton Coated, confirms that the "Utopia Inkjet and Utopia Book Inkjet are optimized for the HP T-series presses through an exclusive arrangement with HP in North America." He adds that they are also certified by Kodak: Utopia Book Inkjet is 4 Diamond certified (enhanced color) and Utopia Inkjet Dull is 5 Diamond certified (offset class). Other systems are dye-based and focused on transactional and transpromo, and do not have sufficient drying for Utopia Inkjet, but Bradshaw points out that some of these press manufacturers are working on drying systems.

Initially, book publishing was the largest market for Appleton Coated's inkjet line but, with the addition of Utopia Inkjet Gloss, applications such as direct mail and commercial printing have seen growth. Overall, Bradshaw expects growth of 50 to 100 percent this year, though inkjet remains well under 10 percent of the market.

According to NewPage's Dennis Essary, TrueJet was designed for the Kodak Prosper, but also works on the HP T300 and T400 series without the need for a bonding agent. Printers want their digital papers to match their offset papers, and TrueJet is a match for Sterling Web.

Printed samples provided to me by Essary looked great. TrueJet paper can cost 30 percent more than #3 web, largely because large web orders are often deeply discounted, but Essary notes that the cost of ink has more impact than the cost of paper, and reiterates that printers need to consider the total value proposition.

At the high end of the range, Mitsubishi Imaging (MPM) offers Diamond Jet and Diamond Jet Gloss, which has gloss coating on both sides and works well with both pigment and dye inkjet systems without any on-press treatment. Cathy Cartolano, vice president of sales and technical service, explains, "MPM has extensive experience in coating papers and has extended this expertise to inkjet. MPM is integrated from pulp to paper to packaging, and finished product out the door."

All of the paper manufacturers report that the price for inkjet treated papers is still at a premium over comparable offset papers but, as volumes grow, costs will come down. There are also some volume-based discounts but, even with the discount, prices are higher than for conventional offset papers.

As noted earlier, printers want to print the same grade offset and digital, and an in-line treatment allows them to do this, as does the Xerox CiPress. When considering treated paper versus ordinary paper and an on-press treatment, there is a break point at around 20 percent ink coverage. At that point, the mills suggest it is better to use inkjet treated paper. Any of the in-line treatments add more water that must be evaporated, causing higher energy consumption.

Hybrid Combinations

An emerging scenario involves putting inkjet heads in-line with traditional presses. This provides a "best of both worlds" scenario for customers as it enables them to combine the benefits of offset and flexo printing with the variable nature of high-resolution, four-color inkjet imaging. Schneider notes that RR Donnelley has configured the ProteusJet technology in-line with offset presses, as well as flexo presses. In addition, Donnelley recently announced a two- and three-web ProteusJet MultiWeb configuration. These MultiWebs enable fully variable content to be imaged anywhere across a 30˝ web—and all the way through to the outer envelope.

NewPage offers TrueJet Hybrid, expressly designed to print both offset and inkjet. Samples of TrueJet Hybrid 80# gloss showed excellent results when printed on an M130 web press with a Kodak Versamark imprinting system. The hybrid approach may breathe new life into many web offset presses, and accelerate the penetration of inkjet into high-quality direct mail and promotional printing.

While growth in inkjet has been dramatic, market share remains low. Customers that look at total cost are adopting the new inkjet technologies, while those that only look at unit cost are not. Issues that have limited the volume include the high cost of pigment inks, the cost of inkjet papers, the data that's necessary to exploit variable data capabilities and the challenges printers face in selling a value proposition that gets beyond price per page. As costs come down and databases grow more robust, and printers and their customers better understand the value, market share will grow.

The great growth opportunities are in variable content direct mail, and the large general commercial printing or promotional printing segments. These markets can benefit greatly by targeted print with variable data and high-quality graphics.

Printers have to consider various tradeoffs when selecting the press, the paper and the method of printing. Pigment inks cost more than dye inks, but provide better results when they are used in conjunction with specially treated coated papers for jobs with a lot of color. Specially treated papers can cost more than on-press treatment, but again, often provide better results when there is high ink coverage. Ordinary papers can be a good choice for transactional printing where ink coverage is lower. The right solution will depend on the applications and on customer needs.

Digital printing's real value is to transform a business. Printers need to sell that value. This requires a consultative sale that moves the discussion away from cost per page and more to ROI. PI

About the Author
Jack Miller, known as the Paper Guru, is principal consultant at Market-Intell, a supplier of strategic consulting and "Need to Know" market intelligence in paper, print and packaging. Formerly, Miller served as the senior consultant, North America, with Pira International and was also director of market intelligence at Domtar. Contact him by e-mail at jack.miller@market-intell.com.