NOTE: All illustrations and photos have been removed from this article.
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Depending on which vendor you speak with, processless computer to plate (P-CTP) systems are either available and competitive today, or are still over the horizon. Regardless of where they are, they are poised to supplant other approaches to CTP by allowing printers to satisfy changing customer needs more efficiently while enabling them to manage their financial and environmental performance more effectively. Unfortunately, conflicting claims around this new technology have left many printers in a fog about what processless is and its potential benefits. The technology, although new, is indeed available and should be on display and ready for purchase from some firms come Graph Expo. Those printers intent on being early adopters can plan on all the traditional benefits of CTP, plus the new perks of processless. Conventional CTP already offers many advantages over conventional platemaking: better register, the elimination of film-related costs, and the ability to employ stochastic screening, to name just a few. Most CTP systems in use today require the installation of plate processors. Some also require ovens for pre-exposure or post-exposure baking. P-CTP systems promise to eliminate the headaches associated with processing. Given that benefit, it should come as no surprise that most users and vendors have been looking toward so-called "processless" plates as the Holy Grail of CTP for more than a decade. This is especially the case when the costs, sources of variability, and environmental impacts associated with current CTP solutions are accounted for. Given the choice, what printer wouldn't want to free up the capital, space, and labor dedicated to operating processors with caustic developer solutions, or eliminate the costs and risks associated with the safe and responsible disposal of waste effluents? What printer wouldn't welcome regaining the time lost to processing plates and processing-related plate remakes? What printer wouldn't like to simplify their business and print in a smarter and more responsible way? Until recently, Presstek was the only vendor marketing processless plates. However, if the number of "processless" technology demonstrations and product announcements made at Drupa 2004 are any indication of things to come, it is likely that Agfa, Creo, Fuji, Konica-Minolta, Kodak Polychrome Graphics, and several other vendors will soon join Presstek in competing for P-CTP business. Many versions of the Holy Grail will be in sight and/or on sale at Graph Expo. With the growing pressure for businesses to become more nimble, lean, and responsible, more and more CTP vendors can be expected to proclaim the benefits of processless CTP systems. A Plate by Any Other Name For now, the term "processless" appears to have the cache of the word "digital" circa 1995; everyone may be starting to use it, but with varying definitions. As the technology becomes more defined and refined, users will likely see more and better information about the features, benefits and limitations of various P-CTP solutions. In particular, vendors should be expected to voluntarily disclose all relevant information about the lifecycle health, safety, and environmental (HSE) effects of all of their CTP offerings. P-CTP's current state comes after more than a decade's worth of widespread and imprecise use of the term "processless." However, with the market heating up, vendors are expressing concern that adoption of processless plate technologies could be hampered if potential buyers are perplexed by overly broad or conflicting definitions. According to John O'Rourke, director of CTP marketing for Presstek, "Lack of standardized nomenclature has the potential to create confusion in the marketplace." To help make sense of the field, Mr. O'Rourke hopes that the term "processless" will be reserved for the overall category with some specific definitions of subcategories. His suggestion segments the processless field into several product categories (and are provided with the author's own acronyms): * Process-free CTP (pfCTP): Complete elimination of all plate developing steps. No additional treatment is required after imaging to prepare a plate for press. Presstek's Applause thermal ablation plate is an example. In addition, some switchable-polymer approaches to CTP have been discussed that could potentially satisfy this description. * Chemistry-free (cfCTP): No consumable products and no regulated waste stream. Water rinse with drain disposable effluent. Presstek's Anthem plate is an example. * Simple process (spCTP): Such plates require a simple finishing step such as gumming. An improvement over traditional chemical development, but has a consumable component and a waste stream. Agfa's Azura thermal latex coagulation plate is an example. * On-Press Developing (pdCTP): The imaging process either fixes or initiates release of a coating layer that is later removed on press during initial roll-up. KPG's Thermal Direct Plate and Fuji's Brillia LDNS Thermal plate are examples. According to Mr. O'Rourke, some inkjet CTP approaches may conform to one or more of the descriptions above because inkjet imaging systems will generally have a consumable component and may require additional post-imaging steps, such as baking, rinsing, or gumming. As for his own company's products, Presstek's lineup includes the Anthem, Aurora, Free-dom, and Pearldry chemistry-free plates, and the Applause process-free plates, all of which are available for sale and will be demonstrated at Graph Expo 2004. Fortunately for the graphic arts industry, vendors recognize there is confusion in the marketplace concerning the term "processless," and they are beginning to address it. Jo Vander Aa, manager of new systems and technologies for Agfa's Graphic Systems/Imaging Solutions group, concurs with Mr. O'Rourke that greater clarity is needed. "We are very well aware of the confusion in the market about the meaning of 'processless,'" Mr. Vander Aa notes. In fact, Agfa plans to clear up some of the confusion with two new, true processless products at Graph Expo--Thermolite and Azura. Thermolite is a thermal non-ablative plate, released for on-press imaging only, and Azura is a thermal non-ablative chemistry-free plate system for CTP applications. Both plates are negative working and use the same basic technology: thermal latex. Even with the vendor acknowledgements of confusion, the marketing of these types of technologies requires some careful word choices. While Presstek's Mr. O'Rourke suggests that the term "processless" be used in reference to the overall category, and that "process-free" be reserved to describe products that eliminate all plate developing steps, Agfa's Mr. Vander Aa maintains that "Processless should be used to Indicate plate systems in which the platemaking process does not include any steps that use liquid treatments [other than including inkjet fluids] or that generate some form of liquid or solid waste. "We believe that a plate system whereby plate surface debris is removed by the printing process itself can still be called processless if that debris has no significant impact on the paper or other waste treatment from the printing process," he adds, "but a plate system whereby some cleaning process is needed to remove such debris before printing and whereby extra waste is created, should not be called processless." What Are the Benefits? Regardless of differences in how they define their offerings, the majority of vendors see small- to medium-size commercial printers and in-plant printers as being most interested in processless plates, and most vendors agree on the benefits that are likely to be seen as most important to customers. Vendors also observe that the environmental benefits of P-CTP are of greater importance to printers in Europe than they are to printers in the United States. Environmental regulations in some European countries are more stringent, and the continent generally places a greater emphasis on environmental sustainability reporting to investors. Environmental claims, however, may overlook big reasons printers across the globe will want to go processless in the immediate future. Mr. O'Rourke maintains the primary benefit of processless CTP is process simplification. This is achieved through reduction in the steps required to support efficient production-fewer steps means lower costs for consumables, reduced labor, reduced infrastructure requirements, and higher consistency. The elimination of chemical consumables and their associated waste streams might just be one of the secondary benefits of the technology. Saving Space For some, saving space might be the number one reason to go processless. According to Robert Feldberg, vice president of marketing for Konica-Minolta Graphic Imaging USA, "The primary benefits of processless CTP solutions are space savings because of reduced footprint required; more consistent quality due to the elimination of processing variability; and savings achieved through the elimination of chemistry, processor, and reduced maintenance labor costs. "In addition," he added, "environmental benefits are derived though elimination of risks and costs associated with the disposal of chemistry waste effluents and special areas required to safely store chemistry." Konica Minolta will have a live demonstration of its SR-830 thermal IR platesetter and the TF-200 thermal polyester processless plate at Graph Expo. The Screen True Press will be demonstrated at Graph Expo running a processless plate from Konica Minolta, as well. Environmental Concerns Going forward, however, more and more businesses are expected to take environmental concerns to heart. If efficiency and space get early adopters to take up processless, the environmental benefits might be the reason behind processless' second wave. Already, many vendors are quick to adopt methods they see as more environmentally sensitive. For instance, Mr. Vander Aa states, "Lowering the environmental impacts of products is a major goal for Agfa, not just because of our company ethics and our own corporate guidelines, but because we are convinced that the environmental awareness and concern of customers--as well as ever tightening legal regulations--will continue to grow in the future." Mr. Vander Aa's belief that environmental awareness and concern are likely to be on the rise is supported by the findings of a recent survey of more than 2300 publishers, creative professionals, printers, and other graphic arts professionals in North America. In the study, 66 percent of respondents said they expect the importance of environmental factors in their purchasing decisions their to increase over the next five years. More than two thirds of the creative professionals surveyed stated that vendors do not provide them with enough information about the environmental aspects and impacts associated with their products or services in order for them to make responsible design, purchasing, and production decisions. Process Less and Expect More As more vendors enter the market with processless plates, users will benefit if they insist that vendors agree upon common definitions. And, as interest increases, they may also be able to provide more information about the environmental aspects of their products. Currently, U.S. regulations do not require vendors to publish a Material Safety Data Sheet (MSDS), Article Information Sheet (AIS) or an ISO-compliant Lifecycle Data Sheet (LDS) for plates or developers. The environmentally conscious printer, however, may come to expect it as processless becomes more of reality. Today, the environmental benefits associated with processless CTP may be perceived as secondary to the quality or process simplification benefits. It is also easier today to assign an economic benefit to processless than it is to determine its environmental attributes. But, in the years ahead, in an increasingly greener global economy, the environmental benefits may be a significant and measurable source of value creation. Printing businesses of all sizes, and in all parts of the world, could feel a growing need to adopt platemaking systems that are measurably and verifiably preferable in terms of their environmental performance. Don Carli, is a professor in the department of advertising, design and graphic arts at New York City College of Technology, City University of New York, in Brooklyn. He is also president of Nima Hunter, an independent firm that conducts research and surveys on sustainability and other issues. For information on processless technologies, contact Mr. Carli at processless @nima hunter.com
2007年11月6日星期二
the perks of processless
CTP's co-existing technologies
Violet and thermal vendors target midrange users
In the mid-1990s, CTP options were scarce and users were scarcer. Early adopters included book and financial printers that bought large-format platesetters for single- and limited-color work, followed by magazine and catalog printers. In 2001, PIA (Alexandria, VA) found that about one-half of U.S. commercial web printers had CTP capability, compared to one-tenth of sheetfed, four-up commercial printers.
Nonetheless, according to a 2002 State Street Consultants (Boston) report, larger printers are no longer the dominant buyers in the metal CTP market. Through 1999, more than 75 percent of all metal CTP units installed were reportedly in plants with more than 100 employees. In 2000, the proportion changed to one half, and in 2001, it dropped to little more than one third, equaling installation rates of printers with 50 to 99 employees.
In 2003, look for more of the same as CTP devices continue to move down-market. Today's printers have a wider range of CTP options. Thermal and polymer-based plates are popular for long-run applications — postbaking can extend their run lengths to more than one million impressions. Violet plates are generally rated at 275,000 impressions; polyester plates can be used for up to 25,000 impressions. (See “CTP 101,” April 2003, p. 40.) There's also the tantalizing prospect of processless plates, which have seemingly been “just two years away,” since 1995.
Thermal developments
Although violet vendors are apparently doing a brisk business, thermal technology continues to dominate the market. Violet technology represents about 16 percent of the 16,000 metal CTP installations worldwide, according to RIT's (Rochester, NY) Frank Romano.
“Thermal is still the market leader,” asserts Jack Weithoff, Kodak Polychrome Graphics (KPG) (Norwalk, CT) worldwide staff vice president, plates. The exec emphasizes that while KPG's thermal plates can be used for extremely long runs, “the technology continues to be adopted for shorter runs,” and notes that one of KPG's customers uses thermal plates for runs of 20,000 because of the plates' consistency, quality and ease of use.
While KPG's no-preheat, no-postbake thermal SWORD plate can handle run lengths of 400,000 impressions, the vendor has found that most printers' runs are under 100,000. On the processless side, KPG is working on a nonablative plate with open chemistry but hasn't announced further details.
“Most of our four- and eight-up devices are compatible or qualified to run both chemical-free as well as traditional thermal media,” notes Joe Luckett, Creo's (Billerica, MA) marketing manager, CTP devices. “Chemical-free is an ideal fit for a lot of small to midsize printers. A lot of their runs are typically under the 100,000 range. And they are removing the cost of the processor and the chemistry itself, which can be significant, not to mention the hassle of chemical storage and disposal. Ultimately, they're operating as a greener company.”
Tom Bevan, director of sales and marketing for PDI (Racine, WI), says the company is focusing on the next generation of its Eclipse Thermal, a no-bake polymer-over-aluminum plate. “We think we can bring its performance level from its current 500,000 impressions to 750,000,” he explains. The exec notes that Eclipse's small-footprint processor is speedy. “From the start of imaging to the plate being ready to go on press takes 10 minutes, vs. 30 minutes with a plate that has to be pre- and postbaked.”
PDI is continuing its no-process R&D, but isn't interested in producing a violet plate. “We think violet is on the really small end of the market,” says Bevan. “Over time, [other vendors] may make progress on the run-length front, but we don't run into that often with our customers.”
“There is a trend toward positive thermal plates, because there's no prebaking required,” says Robert Dainton, technical director, Citiplate (Roslyn Heights, NY), which offers silverless photopolymer plates for UV, thermal and violet CTP applications. “The drawback is you have to postbake because the image is soft.” The exec notes that one of its customers is investigating other thermal options, because its prebake oven costs $12,000 a year to operate. “The customer had considered using a silver plate, but that's not an option because it doesn't give them the required run length,” says Dainton. “So they're looking at photopolymer, which will, with just one postbake oven for extra-long run lengths.”
Daiton considers “processless” to be a misnomer. “There always has to be some treatment after exposure,” he says. “Either the plate is washed off to get rid of the debris or the debris is removed on press by either the fountain solution or ink. Regardless of what you call it, there's a second step after imaging.”
The exec says new switchable or phase-change polymer developments could result in future plate innovations. “It opens up the potential to have processless plates that aren't thermal or silver or imaged by ablation. It's possible to have a no-process violet plate. We [already] have processless plates that we're running with UV CTP and conventional production methods.”
Chemistry-free/processless plates
In 2002, Presstek's (Hudson, NH) wet-offset, chemical-free Anthem plate was qualified for use on Creo's four- and eight-page Trendsetter Quantum platesetters. The Anthem plate offers dot reproduction of better than two percent to 98 percent at 200 lpi for run lengths up to 100,000 impressions.
In addition to the established Anthem chemical-free plate, Presstek has demonstrated Applause, a wet-offset plate said to be 100-percent process-free — no cleaning, baking or gumming required.
“Our [current] plates are imaged and then either wiped off, as with a direct-imaging (DI) press, or rinsed off with tap water, in the case of Anthem CTP plates,” explains Marc Johnson, Presstek's product-line manager for off-press products. “Because a final clean-up step is required, we don't call [Anthem] processless. The plate cleaner specified for use with Anthem plates is a rinse-only unit (no gum) and is significantly smaller and less expensive than traditional plate processors. We ablate, or blast away, the non-image area. On Anthem, this leaves an ink-receptive layer on the plate. With Applause, ablation reveals the ink-receptive layer.”
Dimension purchasers range from $500,000 to $30 million operations. According to Johnson, the throughput of the four-up Dimension with Anthem or Applause plates is 13 plates per hour at a 2540-dpi resolution, and 20 plates per hour at 1270 dpi. “That throughput is widely acceptable for commercial printers, especially the mainstream shops that we target, but it wouldn't be competitive for newspaper sites that are looking for systems capable of 100 plates per hour,” says Johnson.
Agfa (Ridgefield Park, NJ) led the violet charge at Drupa 2000 with its Galileo. At Ipex 2002, it introduced the Thermolite Plus plate, designed for on-press imaging with a 100,000-impression run length. The DI plate for the Heidelberg Speedmaster 74 DI requires no chemical processing, is non-ablative, and needs no vacuum extraction or filtering. According to David Furman, Agfa senior marketing manager of CTP systems, the firm is currently working on processless technologies for off-press offerings based on similar working principles.
On the platesetter side, Furman says Agfa is selling “a lot more violet” than thermal devices. Debuting at Print 01, Agfa's Palladio is a fully automated, four-up flatbed, violet platesetter that handles Agfa's Lithostar Ultra-V plates and features automated plate loading via a 50-plate media cassette, and automated slipsheet removal. In 2002, Agfa introduced the Xcalibur 45, an eight-up thermal platesetter that outputs 20 40-inch plates per hour at 2400 dpi, in either manual or automatic operation.
Nondisclosure agreements with plate vendors restricted Screen (USA) (Rolling Meadows, IL) from offering specifics, but according to Mike Fox, business development manager for CTP, the company is working with the major plate manufacturers to stay abreast of processless developments. “In terms of visible vs. thermal, all the processless technology we see out there is 830-nm thermal external drum,” declares Fox.
In addition to small and midsize printers adopting CTP, the exec says upgrades are drawing interest. “A lot of the early adopters that have had their units for five to seven years are now looking to upgrade speed and resolution and in some cases, automation.”
In 2002, Screen introduced the external-drum PlateRite 4100 830-nm thermal platesetter. It produces plates for two- and four-page presses at up to 10 plates per hour. The PlateRite 4100 supports a maximum plate size of 32.7 × 26 inches and a minimum plate size of 12.8 × 14.5 inches.
The price is right
“Small to midsize printers are the largest segment currently adopting our platesetter products,” says Peter Vanderlaan, group manager, electronic imaging output products, Enovation Graphic Systems, Inc. (Hanover Park, IL). “Past platesetter technologies were too costly for the small to midsize printers to adopt CTP [until this year]. With products such as the Fujifilm Violet Saber, we offer this segment a CTP device that provides speed, quality and a price-point that fits their ROI needs.”
Vanderlaan says that while the 30-mW Violet Saber series is generating an “outstanding response,” its thermal sales with the Javelin and Dart platesetters remain strong. “Both the thermal and violet products offer unique advantages,” notes Vanderlaan. “Violet offers high productivity and quality at an attractive price point. Thermal offers fine resolutions of up to 300 lpi and long run lengths.”
“Violet remains a productive off-press imaging and processing alternative for customers with many forms per day going to their press equipment,” adds Enovation Graphic Systems' Jim Crawford, group manager, output media. “Violet also can be post-baked for longer-run applications, if required.”
Crawford predicts that “no-process will most likely be a short-run technology for some time. The products have to fit in the users' current environments with little or no performance compromises. Users won't forego processors if there are too many tradeoffs.”
In addition to its Brillia violet photopolymer plate and negative-working photopolymer plate, Fuji is developing the LD-NS dry, thermal, processless plate for Komori's (Rolling Meadows, IL) S40 D and Heidelberg's (Kennesaw, GA) Speedmaster 74 DI.
Violet vastly more popular
“Violet is vastly more popular than anything else for Heidelberg (Kennesaw, GA),” reports Ray Cassino, marketing director, prepress. “We've got some [unique] machines in the two-up format — there's not as much competition as far as providing Speedmaster quality in that format. And, the four-up market has really blossomed.”
The internal-drum Prosetter 52, 74 and 102 are available in two-, four- and eight-up formats, respectively. All are outfitted with 30-mW laser diodes to image silver-halide plates. Heidelberg also offers the thermal Topsetter P74, which supports plate sizes for the QM46, GTO46 and Speedmaster CD 74.
On the processless side, Cassino says more plate manufacturers are getting closer to achieving a viable product. “But we're still waiting for someone to give us a processless plate with a long run length. Without chemical processing, it's hard to get plates with a sufficient sensitivity,” he explains.
Cassino doubts the industry will accept a processless plate incapable of longer runs. “For most printers, a run length of 100,000 impressions would be fine,” he observes. “But you won't convince the whole market to go processless until you hit well over 500,000.”
The exec also expects new processless solutions to be nonablative. “That's probably the industry preference. With an ablative plate, you have to ensure you remove 100 percent of the debris — 99.9 percent isn't good enough. There's also an environmental issue with the fumes and an optics issue with the debris flying around.”
While many CTP discussions focus on plate technologies, proofing options are equally important to Heidelberg's customers. “We've found a lot of people choose the proofer first,” says Cassino. “We sort of push them that way, though, because you can't talk about a platesetter until they're comfortable with the proofer.”
Heidelberg packages Hewlett-Packard's (HP) (Palo Alto, CA) DesignJet printers and its own PrintOpen color-management software with many prepress workflow solutions. “We've been very successful with it,” says the exec. “Color management and ICC profiles bring inkjet printers closer to the press sheet than can be achieved with traditional photomechanical dot proofs.” (See “The new proof,” February 2003, p. 28.)
Esko-Graphics' (Kennesaw, GA) CTP philosophy is built on flexibility. “We offer a complete line of platesetters,” explains Dave Mitchell, director of sales. “We have total flexibility both in automation and choice of lasers and plates (violet polymer, violet silver, YAG, argon, HeNe, thermal) with ‘FreeBeam Technology.’ PlateDriver users can choose the plate type and vendor that suit their specific pricing and production needs.”
In 2002, Esko-Graphics introduced a four-up version of its PlateDriver, the QPS 4. Because the QPS 4 violet-laser system has variable power levels (the diode can image from two mW to 30 mW), printers can use any violet-sensitive CTP plate — either silver halide or photopolymer.
“Violet technology is no longer relegated to short-run jobs,” asserts Mitchell. “New polymer violet plates introduced within the past six months have impressive run lengths. Unbaked, they are good for as many as 250,000 impressions. Baked plates can produce as many as one million impressions.”
While noting that “total elimination of chemistry is everyone's desire,” the exec says it is difficult to predict when more processless options will arrive. “The expansion of future processless plates will depend on many factors, including how they compare to current CTP plates' performance and pricing,” says Mitchell. Like Cassino, Mitchell cites achieving longer run lengths and nonablation as processless goals.
Ultimately, regardless of a company's size, the plate choice begins in the pressroom. Printers must review printability, run-length and format requirements. On the prepress side, workflow considerations must also be evaluated, issues that will be discussed in our June issue.
Fujifilm Graphic Systems Div. to be integrated with Enovation
Enovation Graphic Systems, Inc. (Valhalla, NY), the distributor arm of Fujifilm Co. (Elmsford, NY), has announced the integration of Fuji Photo Film U.S.A., Inc.'s Graphic Systems Div. (Hanover Park, IL) into Enovation's current organization.
Stephen Bennett, director of product marketing for Fuji's Graphic Systems Div., says Enovation's integration of this division's product development, marketing, sales, training, service and technical-support resources is “a natural business progression.” Bennett notes that initially, about 20 percent of the division's business came from Enovation. “Today, it's about 80 percent of our business,” he says.
Enovation was created in 2001, when Fujifilm acquired PrimeSource Corp. (Pennsauken, NJ), Heartland Imaging (Kansas City, KS) and Graphic Systems, Inc. (Minneapolis).
“This is another development toward the broader and inexorable reorganization of the entire graphic-arts channel,” writes Robert FitzPatrick, WhatTheyThink.com columnist and co-publisher of “The Eagle,” an online journal dedicated to distribution/channel issues, in his analysis of the situation. “The integration is one more step in Fuji's longer-term strategy of lowering distribution costs… By integrating the Graphic Systems Div. and Enovation, Fuji is eliminating many redundant operational costs.”
This past March, PrimeNet Marketing Services (Clearwater, FL) replaced its four-up capstan imagesetter with a Presstek (Hudson, NH) Dimension 400 platesetter running Anthem plates. For its 12-employee, in-plant print shop, the direct-mail marketing company wanted a small-footprint device that didn't require safelight handling. Environmental considerations also were paramount.
“Our local municipality has put large [pollution] preventive measures in place,” explains Joe Mannino, PrimeNet production manager. A year ago, PrimeNet was fined and ordered to install a flume-monitoring device to measure its wastewater's silver content. The company also had to pay for an independent analysis of its wastewater. All told, PrimeNet spent at least $12,000 on compliance measures.
Mannino reports, however, that the chemistry-free Dimension/Anthem combination has alleviated the company's silver-disposal issue. “The environmental impact of the Anthem is irrelevant,” he claims. “A simple water wash removes inert carbon from the plate. We call it the car wash. It's a squeegee-roller system that uses plain tap water.”
The Anthem plate reportedly offers dot reproduction of better than two percent to 98 percent at 200 lpi for run lengths of up to 100,000 impressions. Run lengths at PrimeNet are an average of 7,500 sheets. “We're a short-run shop,” says Mannino. “A lot of what we do is four-color shells. We print them in large quantities and imprint the sale information.”
Most of this work is done on PrimeNet's Heidelberg MO and Speedmaster 72. The in-plant printer also has a Didde web press for printing forms, as well as two Halm envelope presses. A seven-color Epson 7600 inkjet device is used for proofing.
Mannino says xpedx (Lenexa, KS), which supplied the all-digital workflow, played a key role in the installation's success. “It was the only graphic-arts vendor to consider our entire situation, rather than push us toward a certain brand.”
Currently, Presstek's Anthem is the only chemistry-free plate that is commercially available for the Dimension platesetter. “That caused me momentary concern,” concedes Mannino. “But the fact that one vendor is responsible for the plate and machine [convinced] me. Unlike an imagesetter, where you can have three different film, chemical and imagesetter manufacturers and a lot of finger-pointing if things go wrong, we are calling [only one] company.”
Mannino says the all-digital workflow is more efficient than originally anticipated. “Press operators don't have to worry about registration as much or fight dot gain from film. We've been able to reduce makeready by 50 percent and increase our capacity by 10,000 impressions.”
The production manager notes that print quality also has dramatically improved. “We used to theorize that our presses' dot gain was obscene,” he relates. “We weren't really measuring it and we had ‘yucky’ print quality, to quote one of our designers. Well, now our art department doesn't have to compromise — what they're giving us is what they're getting, not a dot less. It's given us a marketing edge that we previously didn't have.”
In the mid-1990s, CTP options were scarce and users were scarcer. Early adopters included book and financial printers that bought large-format platesetters for single- and limited-color work, followed by magazine and catalog printers. In 2001, PIA (Alexandria, VA) found that about one-half of U.S. commercial web printers had CTP capability, compared to one-tenth of sheetfed, four-up commercial printers.
Nonetheless, according to a 2002 State Street Consultants (Boston) report, larger printers are no longer the dominant buyers in the metal CTP market. Through 1999, more than 75 percent of all metal CTP units installed were reportedly in plants with more than 100 employees. In 2000, the proportion changed to one half, and in 2001, it dropped to little more than one third, equaling installation rates of printers with 50 to 99 employees.
In 2003, look for more of the same as CTP devices continue to move down-market. Today's printers have a wider range of CTP options. Thermal and polymer-based plates are popular for long-run applications — postbaking can extend their run lengths to more than one million impressions. Violet plates are generally rated at 275,000 impressions; polyester plates can be used for up to 25,000 impressions. (See “CTP 101,” April 2003, p. 40.) There's also the tantalizing prospect of processless plates, which have seemingly been “just two years away,” since 1995.
Thermal developments
Although violet vendors are apparently doing a brisk business, thermal technology continues to dominate the market. Violet technology represents about 16 percent of the 16,000 metal CTP installations worldwide, according to RIT's (Rochester, NY) Frank Romano.
“Thermal is still the market leader,” asserts Jack Weithoff, Kodak Polychrome Graphics (KPG) (Norwalk, CT) worldwide staff vice president, plates. The exec emphasizes that while KPG's thermal plates can be used for extremely long runs, “the technology continues to be adopted for shorter runs,” and notes that one of KPG's customers uses thermal plates for runs of 20,000 because of the plates' consistency, quality and ease of use.
While KPG's no-preheat, no-postbake thermal SWORD plate can handle run lengths of 400,000 impressions, the vendor has found that most printers' runs are under 100,000. On the processless side, KPG is working on a nonablative plate with open chemistry but hasn't announced further details.
“Most of our four- and eight-up devices are compatible or qualified to run both chemical-free as well as traditional thermal media,” notes Joe Luckett, Creo's (Billerica, MA) marketing manager, CTP devices. “Chemical-free is an ideal fit for a lot of small to midsize printers. A lot of their runs are typically under the 100,000 range. And they are removing the cost of the processor and the chemistry itself, which can be significant, not to mention the hassle of chemical storage and disposal. Ultimately, they're operating as a greener company.”
Tom Bevan, director of sales and marketing for PDI (Racine, WI), says the company is focusing on the next generation of its Eclipse Thermal, a no-bake polymer-over-aluminum plate. “We think we can bring its performance level from its current 500,000 impressions to 750,000,” he explains. The exec notes that Eclipse's small-footprint processor is speedy. “From the start of imaging to the plate being ready to go on press takes 10 minutes, vs. 30 minutes with a plate that has to be pre- and postbaked.”
PDI is continuing its no-process R&D, but isn't interested in producing a violet plate. “We think violet is on the really small end of the market,” says Bevan. “Over time, [other vendors] may make progress on the run-length front, but we don't run into that often with our customers.”
“There is a trend toward positive thermal plates, because there's no prebaking required,” says Robert Dainton, technical director, Citiplate (Roslyn Heights, NY), which offers silverless photopolymer plates for UV, thermal and violet CTP applications. “The drawback is you have to postbake because the image is soft.” The exec notes that one of its customers is investigating other thermal options, because its prebake oven costs $12,000 a year to operate. “The customer had considered using a silver plate, but that's not an option because it doesn't give them the required run length,” says Dainton. “So they're looking at photopolymer, which will, with just one postbake oven for extra-long run lengths.”
Daiton considers “processless” to be a misnomer. “There always has to be some treatment after exposure,” he says. “Either the plate is washed off to get rid of the debris or the debris is removed on press by either the fountain solution or ink. Regardless of what you call it, there's a second step after imaging.”
The exec says new switchable or phase-change polymer developments could result in future plate innovations. “It opens up the potential to have processless plates that aren't thermal or silver or imaged by ablation. It's possible to have a no-process violet plate. We [already] have processless plates that we're running with UV CTP and conventional production methods.”
Chemistry-free/processless plates
In 2002, Presstek's (Hudson, NH) wet-offset, chemical-free Anthem plate was qualified for use on Creo's four- and eight-page Trendsetter Quantum platesetters. The Anthem plate offers dot reproduction of better than two percent to 98 percent at 200 lpi for run lengths up to 100,000 impressions.
In addition to the established Anthem chemical-free plate, Presstek has demonstrated Applause, a wet-offset plate said to be 100-percent process-free — no cleaning, baking or gumming required.
“Our [current] plates are imaged and then either wiped off, as with a direct-imaging (DI) press, or rinsed off with tap water, in the case of Anthem CTP plates,” explains Marc Johnson, Presstek's product-line manager for off-press products. “Because a final clean-up step is required, we don't call [Anthem] processless. The plate cleaner specified for use with Anthem plates is a rinse-only unit (no gum) and is significantly smaller and less expensive than traditional plate processors. We ablate, or blast away, the non-image area. On Anthem, this leaves an ink-receptive layer on the plate. With Applause, ablation reveals the ink-receptive layer.”
Dimension purchasers range from $500,000 to $30 million operations. According to Johnson, the throughput of the four-up Dimension with Anthem or Applause plates is 13 plates per hour at a 2540-dpi resolution, and 20 plates per hour at 1270 dpi. “That throughput is widely acceptable for commercial printers, especially the mainstream shops that we target, but it wouldn't be competitive for newspaper sites that are looking for systems capable of 100 plates per hour,” says Johnson.
Agfa (Ridgefield Park, NJ) led the violet charge at Drupa 2000 with its Galileo. At Ipex 2002, it introduced the Thermolite Plus plate, designed for on-press imaging with a 100,000-impression run length. The DI plate for the Heidelberg Speedmaster 74 DI requires no chemical processing, is non-ablative, and needs no vacuum extraction or filtering. According to David Furman, Agfa senior marketing manager of CTP systems, the firm is currently working on processless technologies for off-press offerings based on similar working principles.
On the platesetter side, Furman says Agfa is selling “a lot more violet” than thermal devices. Debuting at Print 01, Agfa's Palladio is a fully automated, four-up flatbed, violet platesetter that handles Agfa's Lithostar Ultra-V plates and features automated plate loading via a 50-plate media cassette, and automated slipsheet removal. In 2002, Agfa introduced the Xcalibur 45, an eight-up thermal platesetter that outputs 20 40-inch plates per hour at 2400 dpi, in either manual or automatic operation.
Nondisclosure agreements with plate vendors restricted Screen (USA) (Rolling Meadows, IL) from offering specifics, but according to Mike Fox, business development manager for CTP, the company is working with the major plate manufacturers to stay abreast of processless developments. “In terms of visible vs. thermal, all the processless technology we see out there is 830-nm thermal external drum,” declares Fox.
In addition to small and midsize printers adopting CTP, the exec says upgrades are drawing interest. “A lot of the early adopters that have had their units for five to seven years are now looking to upgrade speed and resolution and in some cases, automation.”
In 2002, Screen introduced the external-drum PlateRite 4100 830-nm thermal platesetter. It produces plates for two- and four-page presses at up to 10 plates per hour. The PlateRite 4100 supports a maximum plate size of 32.7 × 26 inches and a minimum plate size of 12.8 × 14.5 inches.
The price is right
“Small to midsize printers are the largest segment currently adopting our platesetter products,” says Peter Vanderlaan, group manager, electronic imaging output products, Enovation Graphic Systems, Inc. (Hanover Park, IL). “Past platesetter technologies were too costly for the small to midsize printers to adopt CTP [until this year]. With products such as the Fujifilm Violet Saber, we offer this segment a CTP device that provides speed, quality and a price-point that fits their ROI needs.”
Vanderlaan says that while the 30-mW Violet Saber series is generating an “outstanding response,” its thermal sales with the Javelin and Dart platesetters remain strong. “Both the thermal and violet products offer unique advantages,” notes Vanderlaan. “Violet offers high productivity and quality at an attractive price point. Thermal offers fine resolutions of up to 300 lpi and long run lengths.”
“Violet remains a productive off-press imaging and processing alternative for customers with many forms per day going to their press equipment,” adds Enovation Graphic Systems' Jim Crawford, group manager, output media. “Violet also can be post-baked for longer-run applications, if required.”
Crawford predicts that “no-process will most likely be a short-run technology for some time. The products have to fit in the users' current environments with little or no performance compromises. Users won't forego processors if there are too many tradeoffs.”
In addition to its Brillia violet photopolymer plate and negative-working photopolymer plate, Fuji is developing the LD-NS dry, thermal, processless plate for Komori's (Rolling Meadows, IL) S40 D and Heidelberg's (Kennesaw, GA) Speedmaster 74 DI.
Violet vastly more popular
“Violet is vastly more popular than anything else for Heidelberg (Kennesaw, GA),” reports Ray Cassino, marketing director, prepress. “We've got some [unique] machines in the two-up format — there's not as much competition as far as providing Speedmaster quality in that format. And, the four-up market has really blossomed.”
The internal-drum Prosetter 52, 74 and 102 are available in two-, four- and eight-up formats, respectively. All are outfitted with 30-mW laser diodes to image silver-halide plates. Heidelberg also offers the thermal Topsetter P74, which supports plate sizes for the QM46, GTO46 and Speedmaster CD 74.
On the processless side, Cassino says more plate manufacturers are getting closer to achieving a viable product. “But we're still waiting for someone to give us a processless plate with a long run length. Without chemical processing, it's hard to get plates with a sufficient sensitivity,” he explains.
Cassino doubts the industry will accept a processless plate incapable of longer runs. “For most printers, a run length of 100,000 impressions would be fine,” he observes. “But you won't convince the whole market to go processless until you hit well over 500,000.”
The exec also expects new processless solutions to be nonablative. “That's probably the industry preference. With an ablative plate, you have to ensure you remove 100 percent of the debris — 99.9 percent isn't good enough. There's also an environmental issue with the fumes and an optics issue with the debris flying around.”
While many CTP discussions focus on plate technologies, proofing options are equally important to Heidelberg's customers. “We've found a lot of people choose the proofer first,” says Cassino. “We sort of push them that way, though, because you can't talk about a platesetter until they're comfortable with the proofer.”
Heidelberg packages Hewlett-Packard's (HP) (Palo Alto, CA) DesignJet printers and its own PrintOpen color-management software with many prepress workflow solutions. “We've been very successful with it,” says the exec. “Color management and ICC profiles bring inkjet printers closer to the press sheet than can be achieved with traditional photomechanical dot proofs.” (See “The new proof,” February 2003, p. 28.)
Esko-Graphics' (Kennesaw, GA) CTP philosophy is built on flexibility. “We offer a complete line of platesetters,” explains Dave Mitchell, director of sales. “We have total flexibility both in automation and choice of lasers and plates (violet polymer, violet silver, YAG, argon, HeNe, thermal) with ‘FreeBeam Technology.’ PlateDriver users can choose the plate type and vendor that suit their specific pricing and production needs.”
In 2002, Esko-Graphics introduced a four-up version of its PlateDriver, the QPS 4. Because the QPS 4 violet-laser system has variable power levels (the diode can image from two mW to 30 mW), printers can use any violet-sensitive CTP plate — either silver halide or photopolymer.
“Violet technology is no longer relegated to short-run jobs,” asserts Mitchell. “New polymer violet plates introduced within the past six months have impressive run lengths. Unbaked, they are good for as many as 250,000 impressions. Baked plates can produce as many as one million impressions.”
While noting that “total elimination of chemistry is everyone's desire,” the exec says it is difficult to predict when more processless options will arrive. “The expansion of future processless plates will depend on many factors, including how they compare to current CTP plates' performance and pricing,” says Mitchell. Like Cassino, Mitchell cites achieving longer run lengths and nonablation as processless goals.
Ultimately, regardless of a company's size, the plate choice begins in the pressroom. Printers must review printability, run-length and format requirements. On the prepress side, workflow considerations must also be evaluated, issues that will be discussed in our June issue.
Fujifilm Graphic Systems Div. to be integrated with Enovation
Enovation Graphic Systems, Inc. (Valhalla, NY), the distributor arm of Fujifilm Co. (Elmsford, NY), has announced the integration of Fuji Photo Film U.S.A., Inc.'s Graphic Systems Div. (Hanover Park, IL) into Enovation's current organization.
Stephen Bennett, director of product marketing for Fuji's Graphic Systems Div., says Enovation's integration of this division's product development, marketing, sales, training, service and technical-support resources is “a natural business progression.” Bennett notes that initially, about 20 percent of the division's business came from Enovation. “Today, it's about 80 percent of our business,” he says.
Enovation was created in 2001, when Fujifilm acquired PrimeSource Corp. (Pennsauken, NJ), Heartland Imaging (Kansas City, KS) and Graphic Systems, Inc. (Minneapolis).
“This is another development toward the broader and inexorable reorganization of the entire graphic-arts channel,” writes Robert FitzPatrick, WhatTheyThink.com columnist and co-publisher of “The Eagle,” an online journal dedicated to distribution/channel issues, in his analysis of the situation. “The integration is one more step in Fuji's longer-term strategy of lowering distribution costs… By integrating the Graphic Systems Div. and Enovation, Fuji is eliminating many redundant operational costs.”
This past March, PrimeNet Marketing Services (Clearwater, FL) replaced its four-up capstan imagesetter with a Presstek (Hudson, NH) Dimension 400 platesetter running Anthem plates. For its 12-employee, in-plant print shop, the direct-mail marketing company wanted a small-footprint device that didn't require safelight handling. Environmental considerations also were paramount.
“Our local municipality has put large [pollution] preventive measures in place,” explains Joe Mannino, PrimeNet production manager. A year ago, PrimeNet was fined and ordered to install a flume-monitoring device to measure its wastewater's silver content. The company also had to pay for an independent analysis of its wastewater. All told, PrimeNet spent at least $12,000 on compliance measures.
Mannino reports, however, that the chemistry-free Dimension/Anthem combination has alleviated the company's silver-disposal issue. “The environmental impact of the Anthem is irrelevant,” he claims. “A simple water wash removes inert carbon from the plate. We call it the car wash. It's a squeegee-roller system that uses plain tap water.”
The Anthem plate reportedly offers dot reproduction of better than two percent to 98 percent at 200 lpi for run lengths of up to 100,000 impressions. Run lengths at PrimeNet are an average of 7,500 sheets. “We're a short-run shop,” says Mannino. “A lot of what we do is four-color shells. We print them in large quantities and imprint the sale information.”
Most of this work is done on PrimeNet's Heidelberg MO and Speedmaster 72. The in-plant printer also has a Didde web press for printing forms, as well as two Halm envelope presses. A seven-color Epson 7600 inkjet device is used for proofing.
Mannino says xpedx (Lenexa, KS), which supplied the all-digital workflow, played a key role in the installation's success. “It was the only graphic-arts vendor to consider our entire situation, rather than push us toward a certain brand.”
Currently, Presstek's Anthem is the only chemistry-free plate that is commercially available for the Dimension platesetter. “That caused me momentary concern,” concedes Mannino. “But the fact that one vendor is responsible for the plate and machine [convinced] me. Unlike an imagesetter, where you can have three different film, chemical and imagesetter manufacturers and a lot of finger-pointing if things go wrong, we are calling [only one] company.”
Mannino says the all-digital workflow is more efficient than originally anticipated. “Press operators don't have to worry about registration as much or fight dot gain from film. We've been able to reduce makeready by 50 percent and increase our capacity by 10,000 impressions.”
The production manager notes that print quality also has dramatically improved. “We used to theorize that our presses' dot gain was obscene,” he relates. “We weren't really measuring it and we had ‘yucky’ print quality, to quote one of our designers. Well, now our art department doesn't have to compromise — what they're giving us is what they're getting, not a dot less. It's given us a marketing edge that we previously didn't have.”
THERMAL CTP HEATS UP
Computer-to-plate (CTP) has been with us for many years. By the early 1990, for example, black-and-white CTP devices were being marketed and gaining acceptance among printers. Early units exposed paper and polyester plate materials. They filled a specific niche, but were not of much interest to those handling four-color work.
The picture changed in 1995, however, when systems addressing the color market burst onto the scene. At DRUPA 95 in May, experts estimated that 47 CTP systems were announced. But "announced" does not necessarily mean commercially available.
Fortunately, some of the 1995 announcements have turned into reality and color-capable CTP technology is starting to see more widespread application. By 1996, estimates indicated 400 color-capable computer-to-plate systems were installed worldwide, with the U.S. market accounting for roughly half of that number. Today, the installed base has increased to around 500 worldwide.
Future projections are optimistic. One market research firm, for example, estimates an installed base of 3,500 platesetters worldwide by 2000, expecting much of this growth to be fueled by two- and four-page units.
The worldwide metal plate market also is growing. Currently estimated at more than two billion sq. ft., CTP plates are projected to account for 20 percent to 30 percent of that number by the end of 2000.
Most of the installed base of CTP systems use visible laser light technology to digitally image metal plates. But, most recently, interest in thermal CTP technologies is heating up. Thermal computer-to-plate uses heat energy to image plates. Using this approach laser exposure is used to heat the surface of the plate material and change its composition. The plate is imaged as a result of heat applied to the surface.
To assist printers in analyzing the new thermal technologies for CTP, american printer, in partnership with Creo Products, has prepared the following Special Report.
So what's "hot" about thermal CTP?
Thermal imaging units are capable of exposing infrared-sensitive plates, however, they operate in a different manner compared to conventional or laser plates.
When handling light-sensitive plates, what matters is the total exposure time. For instance, a conventional plate can be exposed in one minute using one lamp or in 30 seconds using two lamps. It also is possible for the exposure to proceed for 30 seconds, stop the process and complete it later with another 30 seconds of exposure.
Thermal plates, on the other hand, respond to the peak temperature reached during exposure. At a specified temperature (usually a few hundred degrees centigrade), there is a physical or chemical change in the plate. Any temperature below the prescribed level has no effect. Likewise exposure beyond the threshold does not cause any change in the dot or overexposure.
This processing attribute gives thermal plates a sharpness advantage. Stray heat, or infrared energy, has no effect on the plate, preventing fogging or soft dot edges.
Thermal plates also tend to be insensitive to visible light and can operate in a daylight environment. While in the past visible light platesetters had to be light-tight or used in the dark, thermal plates make it possible to build simpler platesetters. Many platesetters are available with a fully automated plate loading apparatus. If, on the other hand, only a few dozen plates per day are being produced, semi-automatic or manual loading models also are offered.
Most recently thermal plates only were available to work at a wavelength (color of light) of 830 nm. Creo's external drum platesetters operate at 830 nm, for example, along with the Kodak Direct Imaging thermal plate. Both the Heidelberg GTO-DI and Quickmaster-DI presses also image at 830 nm. In comparison, ultraviolet light has a wavelength of 300 nm to 400 nm, while visible laser light is 400 nm to 700 nm.
Presstek's thermal plates, and several plates in development, operate over a broad range of wavelengths, typically 830 to 1100 nm, making them suitable for internal drum platesetters, that operate at 1064 nm when imaging thermal plates.
In any case, the key characteristics of thermal technologies is that a physical or chemical change in the plate (or plate system since some of the technologies use a transfer medium) occurs at a specific temperature. Using heat energy to write an image has implications for quality and workflow.
One way to look at the quality issue is to think of thermal plates as being "digital" in the basic sense of the word. Since a specific temperature must be reached to image the plate, spots are either there or not there--on or off. Theoretically, there should be no partial exposure or fogging of any areas of the plate because no change in the plate material occurs unless that temperature is reached. This allows for very precise imaging.
The workflow benefit is straightforward: thermal plates are sensitized for a fairly high temperature so they can be worked with in daylight conditions with no ill effects.
There has been some confusion regarding another possible benefit. In some cases, the term thermal has been used synonymously with "processorless." While thermal plates that require no processing are in development, the Kodak plate requires processing, albeit simplified, as do other announced products.
The Kodak plate consists of an aluminum substrate equivalent to conventional presensitized plates. The base is coated with a polymer sensitive to 830 nm for direct laser exposure. During imaging, the heat from the laser interacts with the polymer to begin the process of cross-linking the polymer to bind it to the aluminum substrate. This forms the image area.
Next, the plate is conveyed to a unit where it is preheated to strengthen the cross-linking started by the platesetter and to soften the background for removal by the processor.
The processor functions much like any automated plate finisher except that it uses an alkaline solution (potassium hydroxide) as a developer. The potassium hydroxide dissolves the non-image background, which then is scrubbed off with a roller and the plate rinsed with water. The plate then is gummed as it leaves the processor. Post-imaging processing is completed automatically.
The Presstek plate, however, is unique in that it does not require any processing or gumming steps. A wipe down with a clean cloth is required prior to mounting the plate on press.
Available in both "wet" and "dry" plates, the PEARLwet plate from Presstek can be mounted directly on the press where the fountain solution cleans off any residue during the makeready process. Additional gumming is not required as the original protective covering serves the same function as gumming in the conventional process.
Regardless of where you stand on the "processor" issue, thermal proponents and users cite the simplicity of the process and the environmentally friendly operation. Cohber Press (Rochester, NY) installed a Creo platesetter a year ago and uses Kodak developer in its digital plate processor. This developer can be casually disposed of at the end of the day.
It is true that environmental advantages do exist with thermal CTP. As we have already discussed, the Presstek process eliminates the chemistry and the gumming step, which can save both time and money.
On the other hand, users such as Marty Breslow, prepress manager at Continental Web Press (Itasca, IL), don't find the processing step a hardship. Turnaround time for creating a digital plate using the on-line process is as fast as conventional platemaking, assert users.
Once almost the exclusive province of large publication printers, today's thermal platesetters include models for medium-size commercial printing applications. High speed, high resolution and daylight operation are among the features prompting printers to consider thermal CTP options, along with improved quality and faster makereadies typical of all computer-to-plate installations.
Although still new to the marketplace, the prevailing wisdom holds that thermal CTP is the way of the future and will be quickly adopted. For in-depth information on early adopters of thermal CTP, see the three special case history articles in this supplement on pages 33 to 35. Also included is a Buyers' Guide to thermal CTP systems currently available or expected to be available by mid-summer of 1997. We also have included a breakdown of thermal plates on the market or about to be introduced. Please note that we expect more plate and system introductions during 1997, especially from Anitec, Imation and Polaroid.
For more information, please refer to the illustration on page 30 of the April 1997 American Printer.
Work in daylight conditions Environmentally safe; no chemistry disposal Increased dot sharpness Increased process latitude Decreased pressroom makeready Increased process reliability
Periodical printers have been the quickest to adopt computer-to-plate (CTP) technologies. This has undoubtedly been due to the CTP's pressroom benefits, including decreases in makeready times of as much as 25 percent. R.R. Donnelley has been a leader in implementing the technology, as well as Publishers Press and Quad/Graphics.
CTP vendors have seen the highest level of repeat buyers in the periodical printing marketplace, and these CTP devotees point out that the technology's benefits have been greater than anticipated.
In spite of quality improvements and decreased makeready that CTP provides, printers have to deal with existing film. They have devised various workflows to accommodate hybrid jobs--those requiring handling of both digital files and film--but are increasingly purchasing copydot scanners to deal with the issue.
What exactly do these specialized scanners do? Copydot scanners allow traditional film separations to be used in a digital prepress system. However, they are different from continuous-tone scanners, and the bitmap files generated also are unique.
In concept, the copydot scanning process is simple: halftone dots, linework and text on each film separation are captured in digital form so that this data can be reproduced on the plate.
Continuous-tone scanners capture shades of gray and colors. Copydot scanners, however, only see black-and-white; the separated halftone film has no shades of gray--it is either clear or black.
Copydot scanners can use either transmissive or reflective scanning techniques. Transmissive scanning uses a light source on one side of the film and a sensor on the other side to measure light that passes through the film. A reflective scanning system holds film tightly against a white surface, shines light on the film, and a scan head measures the light reflected back. This approach provides easy film handling and can scan reflective copy as well as film.
Because a copydot scanner creates a bitmap file, instructions must be given to produce the right resolution for the target imagesetter/platesetter or the RIP will resample the bitmap data to the output resolution of the imagesetter/platesetter. This resampling can create artifacts that result in poor image quality on the plate.
Additionally, it must be noted that RIPs do not change bitmap data. When working with copydot bitmap files, the RIP can't do color corrections, dot gain compensation or calibration for different plate types. These functions must be performed at the time the scan is done or by separate software.
It also is important to realize that bitmap files are large. For example, uncompressed film for an 81U2 x 11-inch separation at 2400 pixels per inch is about 70 Mb, and a full four-color set is close to 300 Mb.
Systems such as Creo's Renaissance can produce bitmap files in Tagged Image File Format (TIFF) or in Encapsulated PostScript (EPS). Both of these file formats contain the same bitmap data and will create the same image on the plate--they are just formatted differently.
Utilizing a program such as Adobe Photoshop, users can edit individual bitmap separation files to remove dust and scratch marks, edit linework, and perform simple image edits.
The final step in working with copydot data is to save or archive it for future use. No special steps are required, but since the files are very large, they should be compressed before storage. Even compressed, these files are large and will fill storage media quickly. A high-capacity, removeable-medium device with media management software is suitable for storing copydot files.
Here are a few considerations if you are planning the move to computer-to-plate. Suggestions are based on recommendations from the Graphic Arts Technical Foundation. 1 Implement color management systems throughout your scanning, color correction, proofing, output and press areas. 2 Become proficient at preflighting. 3 Do all trapping electronically. 4 Become comfortable with imposition software. 5 Become familiar with digital proofing. Decide on an approach to both internal color proofing and external color proofing in a digital workflow. Build customer confidence through discussions and education. 6 Become confident using a spectrophotometer and proof checking software to maintain quality and consistency of proofs. 7 Upgrade your network. 100BaseT is preferred. 8 Install and become comfortable with network servers that handle OPI functions and queue management. Consider one with color management capabilities. 9 Upgrade archiving systems and software. This means you must have the ability to store--and subsequently locate again--terabytes of information. 10 Implement computer-to-plate and reap the benefits of a digital workflow.
The picture changed in 1995, however, when systems addressing the color market burst onto the scene. At DRUPA 95 in May, experts estimated that 47 CTP systems were announced. But "announced" does not necessarily mean commercially available.
Fortunately, some of the 1995 announcements have turned into reality and color-capable CTP technology is starting to see more widespread application. By 1996, estimates indicated 400 color-capable computer-to-plate systems were installed worldwide, with the U.S. market accounting for roughly half of that number. Today, the installed base has increased to around 500 worldwide.
Future projections are optimistic. One market research firm, for example, estimates an installed base of 3,500 platesetters worldwide by 2000, expecting much of this growth to be fueled by two- and four-page units.
The worldwide metal plate market also is growing. Currently estimated at more than two billion sq. ft., CTP plates are projected to account for 20 percent to 30 percent of that number by the end of 2000.
Most of the installed base of CTP systems use visible laser light technology to digitally image metal plates. But, most recently, interest in thermal CTP technologies is heating up. Thermal computer-to-plate uses heat energy to image plates. Using this approach laser exposure is used to heat the surface of the plate material and change its composition. The plate is imaged as a result of heat applied to the surface.
To assist printers in analyzing the new thermal technologies for CTP, american printer, in partnership with Creo Products, has prepared the following Special Report.
So what's "hot" about thermal CTP?
Thermal imaging units are capable of exposing infrared-sensitive plates, however, they operate in a different manner compared to conventional or laser plates.
When handling light-sensitive plates, what matters is the total exposure time. For instance, a conventional plate can be exposed in one minute using one lamp or in 30 seconds using two lamps. It also is possible for the exposure to proceed for 30 seconds, stop the process and complete it later with another 30 seconds of exposure.
Thermal plates, on the other hand, respond to the peak temperature reached during exposure. At a specified temperature (usually a few hundred degrees centigrade), there is a physical or chemical change in the plate. Any temperature below the prescribed level has no effect. Likewise exposure beyond the threshold does not cause any change in the dot or overexposure.
This processing attribute gives thermal plates a sharpness advantage. Stray heat, or infrared energy, has no effect on the plate, preventing fogging or soft dot edges.
Thermal plates also tend to be insensitive to visible light and can operate in a daylight environment. While in the past visible light platesetters had to be light-tight or used in the dark, thermal plates make it possible to build simpler platesetters. Many platesetters are available with a fully automated plate loading apparatus. If, on the other hand, only a few dozen plates per day are being produced, semi-automatic or manual loading models also are offered.
Most recently thermal plates only were available to work at a wavelength (color of light) of 830 nm. Creo's external drum platesetters operate at 830 nm, for example, along with the Kodak Direct Imaging thermal plate. Both the Heidelberg GTO-DI and Quickmaster-DI presses also image at 830 nm. In comparison, ultraviolet light has a wavelength of 300 nm to 400 nm, while visible laser light is 400 nm to 700 nm.
Presstek's thermal plates, and several plates in development, operate over a broad range of wavelengths, typically 830 to 1100 nm, making them suitable for internal drum platesetters, that operate at 1064 nm when imaging thermal plates.
In any case, the key characteristics of thermal technologies is that a physical or chemical change in the plate (or plate system since some of the technologies use a transfer medium) occurs at a specific temperature. Using heat energy to write an image has implications for quality and workflow.
One way to look at the quality issue is to think of thermal plates as being "digital" in the basic sense of the word. Since a specific temperature must be reached to image the plate, spots are either there or not there--on or off. Theoretically, there should be no partial exposure or fogging of any areas of the plate because no change in the plate material occurs unless that temperature is reached. This allows for very precise imaging.
The workflow benefit is straightforward: thermal plates are sensitized for a fairly high temperature so they can be worked with in daylight conditions with no ill effects.
There has been some confusion regarding another possible benefit. In some cases, the term thermal has been used synonymously with "processorless." While thermal plates that require no processing are in development, the Kodak plate requires processing, albeit simplified, as do other announced products.
The Kodak plate consists of an aluminum substrate equivalent to conventional presensitized plates. The base is coated with a polymer sensitive to 830 nm for direct laser exposure. During imaging, the heat from the laser interacts with the polymer to begin the process of cross-linking the polymer to bind it to the aluminum substrate. This forms the image area.
Next, the plate is conveyed to a unit where it is preheated to strengthen the cross-linking started by the platesetter and to soften the background for removal by the processor.
The processor functions much like any automated plate finisher except that it uses an alkaline solution (potassium hydroxide) as a developer. The potassium hydroxide dissolves the non-image background, which then is scrubbed off with a roller and the plate rinsed with water. The plate then is gummed as it leaves the processor. Post-imaging processing is completed automatically.
The Presstek plate, however, is unique in that it does not require any processing or gumming steps. A wipe down with a clean cloth is required prior to mounting the plate on press.
Available in both "wet" and "dry" plates, the PEARLwet plate from Presstek can be mounted directly on the press where the fountain solution cleans off any residue during the makeready process. Additional gumming is not required as the original protective covering serves the same function as gumming in the conventional process.
Regardless of where you stand on the "processor" issue, thermal proponents and users cite the simplicity of the process and the environmentally friendly operation. Cohber Press (Rochester, NY) installed a Creo platesetter a year ago and uses Kodak developer in its digital plate processor. This developer can be casually disposed of at the end of the day.
It is true that environmental advantages do exist with thermal CTP. As we have already discussed, the Presstek process eliminates the chemistry and the gumming step, which can save both time and money.
On the other hand, users such as Marty Breslow, prepress manager at Continental Web Press (Itasca, IL), don't find the processing step a hardship. Turnaround time for creating a digital plate using the on-line process is as fast as conventional platemaking, assert users.
Once almost the exclusive province of large publication printers, today's thermal platesetters include models for medium-size commercial printing applications. High speed, high resolution and daylight operation are among the features prompting printers to consider thermal CTP options, along with improved quality and faster makereadies typical of all computer-to-plate installations.
Although still new to the marketplace, the prevailing wisdom holds that thermal CTP is the way of the future and will be quickly adopted. For in-depth information on early adopters of thermal CTP, see the three special case history articles in this supplement on pages 33 to 35. Also included is a Buyers' Guide to thermal CTP systems currently available or expected to be available by mid-summer of 1997. We also have included a breakdown of thermal plates on the market or about to be introduced. Please note that we expect more plate and system introductions during 1997, especially from Anitec, Imation and Polaroid.
For more information, please refer to the illustration on page 30 of the April 1997 American Printer.
Work in daylight conditions Environmentally safe; no chemistry disposal Increased dot sharpness Increased process latitude Decreased pressroom makeready Increased process reliability
Periodical printers have been the quickest to adopt computer-to-plate (CTP) technologies. This has undoubtedly been due to the CTP's pressroom benefits, including decreases in makeready times of as much as 25 percent. R.R. Donnelley has been a leader in implementing the technology, as well as Publishers Press and Quad/Graphics.
CTP vendors have seen the highest level of repeat buyers in the periodical printing marketplace, and these CTP devotees point out that the technology's benefits have been greater than anticipated.
In spite of quality improvements and decreased makeready that CTP provides, printers have to deal with existing film. They have devised various workflows to accommodate hybrid jobs--those requiring handling of both digital files and film--but are increasingly purchasing copydot scanners to deal with the issue.
What exactly do these specialized scanners do? Copydot scanners allow traditional film separations to be used in a digital prepress system. However, they are different from continuous-tone scanners, and the bitmap files generated also are unique.
In concept, the copydot scanning process is simple: halftone dots, linework and text on each film separation are captured in digital form so that this data can be reproduced on the plate.
Continuous-tone scanners capture shades of gray and colors. Copydot scanners, however, only see black-and-white; the separated halftone film has no shades of gray--it is either clear or black.
Copydot scanners can use either transmissive or reflective scanning techniques. Transmissive scanning uses a light source on one side of the film and a sensor on the other side to measure light that passes through the film. A reflective scanning system holds film tightly against a white surface, shines light on the film, and a scan head measures the light reflected back. This approach provides easy film handling and can scan reflective copy as well as film.
Because a copydot scanner creates a bitmap file, instructions must be given to produce the right resolution for the target imagesetter/platesetter or the RIP will resample the bitmap data to the output resolution of the imagesetter/platesetter. This resampling can create artifacts that result in poor image quality on the plate.
Additionally, it must be noted that RIPs do not change bitmap data. When working with copydot bitmap files, the RIP can't do color corrections, dot gain compensation or calibration for different plate types. These functions must be performed at the time the scan is done or by separate software.
It also is important to realize that bitmap files are large. For example, uncompressed film for an 81U2 x 11-inch separation at 2400 pixels per inch is about 70 Mb, and a full four-color set is close to 300 Mb.
Systems such as Creo's Renaissance can produce bitmap files in Tagged Image File Format (TIFF) or in Encapsulated PostScript (EPS). Both of these file formats contain the same bitmap data and will create the same image on the plate--they are just formatted differently.
Utilizing a program such as Adobe Photoshop, users can edit individual bitmap separation files to remove dust and scratch marks, edit linework, and perform simple image edits.
The final step in working with copydot data is to save or archive it for future use. No special steps are required, but since the files are very large, they should be compressed before storage. Even compressed, these files are large and will fill storage media quickly. A high-capacity, removeable-medium device with media management software is suitable for storing copydot files.
Here are a few considerations if you are planning the move to computer-to-plate. Suggestions are based on recommendations from the Graphic Arts Technical Foundation. 1 Implement color management systems throughout your scanning, color correction, proofing, output and press areas. 2 Become proficient at preflighting. 3 Do all trapping electronically. 4 Become comfortable with imposition software. 5 Become familiar with digital proofing. Decide on an approach to both internal color proofing and external color proofing in a digital workflow. Build customer confidence through discussions and education. 6 Become confident using a spectrophotometer and proof checking software to maintain quality and consistency of proofs. 7 Upgrade your network. 100BaseT is preferred. 8 Install and become comfortable with network servers that handle OPI functions and queue management. Consider one with color management capabilities. 9 Upgrade archiving systems and software. This means you must have the ability to store--and subsequently locate again--terabytes of information. 10 Implement computer-to-plate and reap the benefits of a digital workflow.
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