For most forms manufacturers, the investment in computer-to-plate systems has been difficult to justify. Only a small number of forms printers have embraced CTP technology for many reasons, including a high incidence of repeat orders, higher plate cost, expensive plate imagers and the need to implement major changes in traditional prepress workflows.
The majority of work for many conventional forms plants is exact repeat orders. For those jobs, manufacturers already have negatives stored, and new plates can be made quickly. Commercial printers, on the other hand, typically have few repeat orders. They normally output new films for every job on digital film imagesetters.
Stumbling Blocks During the Transition
Because typical forms plants have large libraries of negatives that can be used for repeat orders, most manufacturers don't want to incur costs to reset repeat jobs. They also don't want to acquire copy-dot scanners to scan negatives into digital systems. While it's likely that all recent jobs are stored on digital media in forms composition systems, the files may have to be revised to yield fully imposed, plate-sized layouts suitable for CTP. This is a major conversion process for forms plants using 1-up negatives on a step-and-repeat machine to burn plates. Only plants with experience composing and imaging fully imposed, plate-sized negatives can transition easily to CTP for metal plates.
Another challenge manufacturers face when transitioning to CTP is the dependence on only one machine for plates. To avoid production bottlenecks, plants with periodic high workloads may have to invest in more expensive platesetters than would be required under normal conditions. Because CTP systems require special plates matched to specific imagers, prepress trade shops that can back up internal CTP operations may be hard to find. Most plants that switch to CTP still keep their conventional systems running.
The need for fully imposed, plate-sized images is another stumbling block on the path to CTP. Currently, most forms printers and distributors compose art on computers using a variety of software, then output 1-up film on small-format imagesetters. Prepress departments then use step-and-repeat machines to step images across and around as plates are exposed. CTP systems work differently, requiring software that allows digital step-and-repeat functions before plates can be imaged. Forms, page layout and drawing software packages often create files that aren't fully compatible with image-editing and imposition software of CTP systems.
Despite CTP's challenges, transition to filmless prepress workflow is finding gradual acceptance among forms manufacturers. The changing product mix in the forms industry should prompt more plants to look at the advantages of CTP and justify the investment. Today, forms producers are offering more direct mail and commercial printing, areas in which CTP yields significant advantages.
Understanding the Landscape
What kinds of direct-to-plate solutions are available for printers today? Two popular ones exist--direct imaging presses (DI presses), and standalone CTP systems that use digital platesetters for outputting.
Direct imaging on press means that a blank plate, mounted manually or automatically, is imaged on press with all colors in exact register. DI plates can be polyester or metal, and can be designed for waterless or wet offset printing. Plate-imaging laser units are part of presses such as the Heidelberg Quickmaster DI-46-4 and the Speedmaster 74 DI. Several other press suppliers offer sheet-fed offset DI presses. Westmont, Ill.-based equipment supplier MAN Roland introduced a web offset DI press at the Drupa 2000 expo that uses an "erasable" imaging cylinder rather than a plate. DI presses work best for plants that don't have commercial printing-level prepress and plate-making systems, and prepress service bureaus that want to add printing capabilities.
If you're like most printers, you're not looking for a new press but you want to eliminate film. In that case, you need a digital platesetter that images metal or polyester plates. These CTP systems include standalone platesetters linked to digital prepress systems for image assembly, color correction, imposition, trapping, proofing and rasterizing. The primary differences among CTP systems are manual or automatic plate handling, internal or external imaging drum configuration, laser power and wavelength, and compatible plates that can be imaged.
Firms That Blazed Trails
Many short run forms plants use CTPp (polyester) imagers and polyester plates on pack-fed and sheet-fed presses, and a small number of conventional forms plants use CTPm (metal) systems to output metal plates for web presses. (See "Choosing Between Metal and Polyester," p. 28.) Two manufacturers, Valmeyer, Ill.-based MAR Graphics and Brooklyn Park, Minn.-based Northstar Financial Solutions Group, have taken the CTPm plunge. (Northstar is a division of Ennis Business Forms Inc., a manufacturer based in DeSoto, Texas.)
Forms printers thinking about switching to CTPm should consider their current digital prepress processes and their plans to upgrade workflow, says industry expert Ivars Sarkans, president of consulting firm Sarkans & Associates in Los Angeles. "If the printer is making a concentrated effort in direct mail and commercial printing," he says, "a CTPm system can be beneficial in terms of print quality due to lower dot gain, faster press setups with lower waste, and elimination of prepress steps and materials associated with the use of film." CTPm is a technology moving the entire printing industry toward computer-integrated manufacturing, he says.
While dozens of laser platesetters are on the market, most CTPm installations by forms manufacturers have used a system produced by Strobbe Inc., a supplier in Wood Dale, Ill. Strobbe is a division of Punch International, a Belgian company that also owns digital press supplier Xeikon Inc. Strobbe is the only supplier in the market with a forms manufacturer-specific CTPm software/platesetter combination.
"Forms plants have to be very careful in evaluating the potential benefits of CTPm systems," Sarkans says. While many vendors cite reduced dot gain and improved print quality as benefits, he says, those aren't issues for conventional forms printers because the output quality of CTPm systems has outpaced the print quality of most forms presses. "If you're doing PMS line art and 2-color business forms, you won't see any leaps in print quality with a CTPm system," he says. "But short runs on pack or sheet presses can certainly [benefit] from a CTPp system."
Ken Overstreet, president of Ennis' Financial Solutions Group and a company board member, says upgrading to a laser CTPm system was an obvious choice for his firm. The company entered the CTP realm in 1993 with one of Strobbe's beta units. Northstar's transition from film and conventional plate-making to CTPm was gradual. Its major challenge was recomposing existing films for the new system, Overstreet says. In 1998, the company installed a state-of-the-art CTPm system. Northstar was growing its digital workflow and felt the need to create fully imposed images for more jobs. Just before the firm upgraded, it was producing 85 percent of its plates on the CTPm system. Today, the level is more than 99 percent.
Overstreet says manufacturers who want CTPm systems should evaluate their current systems to determine actual costs of making plates, including labor. Printers also should analyze current outputs to see if their systems are keeping pace with the rest of the production process, he says.
Rick Roever, CDC, president of MAR Graphics, says digital know-how is increasingly important for manufacturers. "The increasing digital workflow in our company was one major [reason we adopted CTP technology]," he says. "The savings gained from the elimination of film, supplies, masking sheets, chemicals, tapes, adhesives, the labor for stripping, film exposure and processing--it all adds up. Plus, the new system takes up half the space of our analog system."
Destination: Cost Savings
Printers face common challenges after they switch to CTPm or CTPp systems. Emergency plate-making during night shifts are problematic for some firms, especially ones that don't have night crews versed in prepress. And finding and verifying files and plate-imaging on CTPm systems requires more skills than conventional plate-making. Some manufacturers get around this challenge by allowing production personnel, including press operators, to make plates from negatives when necessary. Some CTP systems are designed to handle this, too. Strobbe's newest system will allow any networked desktop workstation to initiate plate-making with only a few clicks--as easy as printing a page on a laser printer. MAR Graphics is running a beta version of such a system, which can eliminate operator involvement. Roever says the system is working well and has resulted in prepress cost savings and error reduction. "Our goal is to be able to output any plate from any desktop," he says. "We think we'll be there by the end of the year." Roever says he intends to shift employees once devoted to plate-making to other critical functions within the company.
Ivan Verheye, president of Strobbe, says each forms printer aiming to adopt a CTPm system must choose workflow that fits its applications. "Make sure you have the necessary software tools to deal with the gap issues that are specific to the forms industry," he says. "Also, make sure pin integration stays part of the process, as a plate will ultimately be judged when it is mounted on the press and is checked for register with other colors." Verheye also suggests visiting other printers with CTPm systems and listening closely to comments from their prepress teams.
Dennis McGarry, CDC, is vice president of manufacturer and technical programs at DMIA. Email him your comments at dmcgarry@PSDA.org.
Choosing Between Metal and Polyester
Metal computer-to-plate (CTPm) systems are designed to image metal plates, typically for 4-page and larger sheet-fed and all web offset presses (including forms and direct mail presses). Platesetters are distinguished by laser power and wavelength specification in nanometers (nm) within the violet-to-infrared light spectrum. Each wavelength requires compatible plates. Some thermal (infrared) plates can be used immediately after imaging with no further processing; others require baking and processing. Plates for visible light lasers have silver-based or photopolymer emulsions that require conventional chemical or water processing. Most available CTPm plates are designed for wet offset printing, but several products exist for waterless offset printing.
Polyester computer-to-plate (CTPp) systems are popular among forms printers with pack-to-pack presses, quick printers, small commercial print shops and other firms offering short runs. Plate quality has improved so much that on small-format sheet-fed presses, polyester plates can be effective for process color work up to approximately 175 line screens. Two primary benefits of polyester plates are low plate cost and availability of moderately priced platesetters. For typical forms work, plates can be made on an inexpensive capstan imager. Even many older film imagesetters can output polyester plates. These plates are available with silver-based emulsions matched to visible light lasers and require conventional processing. Polyester plates generally aren't used on web presses because they can be distorted by printing pressure and heat, unless runs are very short.
