DIGITAL PLATESETTERS -- The Write One

BY MARK SMITH

A first-time buyer recently posted a message on the CTP Production forum seeking recommendations for "CTP systems" to investigate. The quote marks are important because the term itself sparked a divergent thread in which the question of what CTP means was explored.

This discussion started with a response suggesting the buyer consider the Rampage solution, since it produces plate-ready files. A rebuff quickly followed, asserting that Rampage was not a "system," meaning a piece of hardware capable of writing an image to a digital plate. That, in turn, led to a series of exchanges about whether CTP refers to any or all of digital plates, platesetters and front ends. Or, is the term even broader than that and pertain to the all-digital workflow, which can extend into the pressroom and through the bindery with CIP4/JDF?

To be fair, the original post did contain a preliminary list of hardware manufacturers the buyer was planning to evaluate. This set an expectation that the discussion was to be about platesetters. What the message threads revealed, though, is the extent to which the CTP buying decision really is about a system (digital plate, platesetter, front end and possibly a processor or even ovens) and an underlying imaging technology (thermal vs. violet, primarily). Since the components are so interdependent, this article really should be considered the second part to the story on digital plates that was published (on page 48) in the August issue of Printing Impressions.

CTP system manufacturers are becoming more polarized on the issue of which is the preferred imaging technology—violet or thermal. Violet technology either makes it possible to lower the price point for CTP, or represents a step backward in capabilities, depending on which side is doing the assessment.

CreoScitex and Agfa have been portrayed as being at the opposite ends of the spectrum in the thermal vs. violet debate. The characterization of CreoScitex as strongly pro-thermal is fair. Agfa's position is not as clear-cut, though. The company has been one of the strongest advocates of violet, but it supports both imaging technologies in its plate and platesetter product lines. Presstek is another decidedly pro-thermal company, in both its plate and platesetter product lines. A number of other manufacturers fall somewhere in the middle, offering both visible light and thermal products.

Complicated Debate
Potential buyers seeking to compare violet vs. thermal imaging can quickly get bogged down in a morass of claims and counterclaims. The debate is complicated by the current state of development in violet plates and platesetters. The technology itself is at crossroad, with the pending introduction of 30mW laser diodes holding the promise of imaging photopolymer plates.

The current generation of violet systems uses 5mW laser diodes, which means the plates must have a silver-halide coating in order to be sensitive to this relatively low level of energy. Thermal proponents point out that using silver raises issues regarding plate handling, chemistry/developer management and silver recovery/disposal, which make the process more complicated and adds to the total cost of ownership. Violet advocates naturally play down such concerns, but also note that 30mW/photopolymer violet systems eliminate the need for using silver. This gets into the area of debating current vs. future technology, though.

Thermal advocates do much the same thing in touting the technology's potential to enable processless plate making. While it is possible to install a processless system today, the choice of plates currently is extremely limited and the run lengths supported tend to be lower than with other digital plates. In addition, ablative technology requires that a debris removal system be added to a thermal platesetter, which adds to the cost of the device and requires some maintenance (primarily filter changes).

Processless technology is widely seen as an important area of development going forward but, like violet, its full potential has yet to be realized. Also, buyers should keep in mind that not all thermal systems are equal when it comes to using processless plates. The differences between 830nm/external-drum and 1,064nm/internal-drum thermal platforms can impact their suitability for imaging the plates.

Along with providing fast imaging speeds, violet technology has been championed for its ability to lower the cost of CTP. This assertion is largely based on the premise that the laser diodes are cheaper because they are a mass-produced product. The diodes' primary application is in DVD/DVR devices for the home entertainment market.

Both sides like to talk about the "total cost of ownership" in comparing violet and thermal imaging. This means looking beyond the capital cost of the device itself and factoring in the price of plates, required peripherals (processors, ovens, etc.), operating environment, maintenance costs (laser replacements) and performance on-press. The earlier discussion about concerns related to using silver is an example of potential added costs.

Similarly, the original knock against thermal systems was that many required pre- and/or post-imaging baking units. The length of the plate-making line itself sometimes ended up being a barrier to installation, in addition to the added capital and operating costs of the units. Many thermal plates no longer require a pre-heat step and baking usually is only required to support longer runs—up to 1 million impressions or more.

The cost of laser replacement is a trickier issue. Manufacturers like to talk about the rated life cycle of these components, but straightforward comparisons of the numbers may be misleading. Laser diodes, such as violet units, can be switched on and off very quickly and the manufacturer's rating only refers to the time the diode is active. Therefore, less of the diode's life expectancy is used up imaging each plate, so it can image more plates than other laser sources per hour of its rated life cycle.

The emphasis on costs is tied into the general perception that the small- to mid-size printer segment is the new hotspot for CTP activity. Manufacturers have responded by introducing new four-up, and even two-up, machines targeted to this market. This has been considered to be the sweet spot for violet systems, but makers of thermal systems also are focusing on this market segment.

Products Roar at PRINT
Heidelberg's entry into the marketplace was widely anticipated and seen by advocates of violet imaging as validating the technology. At PRINT 01, the manufacturer formally introduced its Prosetter family of internal-drum, violet-laser-diode (5mW) platesetters in two-, four- and eight-up formats.

A number of other manufacturers also introduced violet platesetter models:

Agfa extended its violet offerings with the introduction of the Palladio, a fully automated, four-up flatbed platesetter specifically designed for small- to medium-size printers.

Purup-Eskofot unveiled Plate-Driver, a new generation of plate-setters that can be configured with a range of laser types. The options currently include violet (5mW, with 30mW to come), argon-ion, FD-YAG and thermal.

ECRM displayed its TigerCat (four-up) and TigerCat2 (two-up) platesetters, which are both now available in violet-laser versions.

Escher-Grad introduced the Cobalt-8 CTP system, which features the new 30mW violet laser diode to enable imaging of both silver-halide and photopolymer plates.

Global Graphics Hardware debuted the Cirrus 2 B3 platesetter with a choice of a HeNe or violet laser and driven by an integrated RIP to image plates up to 19.9x20.7˝.

On the thermal side, CreoScitex launched a new class of entry-level models across its product lines in response to CTP's down-market migration. This includes thermal platesetters that offer a subset of the capabilities of its fully featured models, with an upgrade path available.

Presstek Inc. didn't introduce any platesetters, but it did demonstrate a new Automated Plate Loading system for its current models. The system is said to be specifically designed for the small- to mid-size shop and will be offered as an upgrade option starting early in 2002.

(For more on the great thermal vs. violet debate, see the accompanying sidebar to this story.)

The processless plate arena saw the entry of an interesting new competitor at PRINT 01. Computer-to-conventional plate (CTcP) manufacturer basysPrint announced that Kodak Polychrome Graphics' DirectPrint no-process conventional plates can now be imaged by the company's UV-Setter product line. The negative-working, aluminum plates are said to support a tonal range of 1-98 percent, handle runs up to 100,000 impressions and work with common pressroom chemicals. Once exposed, the plate reportedly is made ready to print by the action of the press unit within five to 10 sheets.

Not to be confused with visible violet systems, basysPrint's UV-Setter uses a regular UV (ultra-violet) lamp to digitally expose most UV-sensitive materials, including conventional plates and proofs. Its current systems use a Digital Micromirror Device (DMD) to direct the UV light through an optical lens onto the plate to write a spot or divert it to prevent imaging. The system is said to produce square pixels with sharply defined edges, which gives the appearance of higher quality imaging at lower resolutions.

For more information on plate-setters shown at PRINT 01, see the special post-show product section starting on page 24.

Seeing The Light, Or Feeling The Heat?

Platesetter manufacturers tend to have strong opinions about the merits of violet and thermal imaging technologies. Here's a sampling:

Raymond Cassino, director of marketing, Heidelberg USA:
One product can't fit all the needs of such a broad market as CTP, so Heidelberg offers multiple imaging technologies—the Topsetter thermal and the new Prosetter violet platesetter families. Each solution has its own benefits. For example:

* The total cost of ownership is significantly lower with violet technology compared to thermal technology.

* Thermal plates offer run lengths of 1 million (with post baking) impressions, while the run length for violet materials is 300,000.

* We are introducing a two-up format with the violet Prosetter.

* Thermal is better suited for UV ink applications.

David Furhman, national plate manager, Agfa Corp.:
The base of customers who are purchasing CTP units is moving down to the small- to mid-size commercial printing segments. Violet is a perfect fit into these segments for several reasons:

* There is no other technology that can offer the same combination of speed, quality and automation at the price levels one can get with violet.

* The small- to mid-size commercial printing segment does not require long run lengths. Violet is the perfect fit since most violet plates can run up to 350,000 impressions without baking or the need for a rinse/gum unit.

Peter Vanderlaan, product development manager, electronic imaging hardware, Fuji Photo Film U.S.A.:
Fuji offers both visible light and thermal technology in our plate and platesetter lines because each product offers its own unique features (i.e., automation, run length, plate handling environment, pricing, etc.). Visible light (which includes violet) offers high productivity and short- to medium-run length support at a very attractive price. Thermal offers yellow/room light plate handling and long run lengths.

Fuji will release its new violet plate shortly after PRINT 01 and, in early 2002, also will be introducing a violet platesetter based off our Saber Luxel P-9600 CTP technology.

Mike Fox, vice president of sales and marketing, Screen (USA):
Screen does not manufacture plates and/or proofing consumables. Therefore, we simply look to the market to determine the preferred imaging technology and respond accordingly.

Screen currently designs and manufactures both visible light and thermal platesetters. The trend has been toward adoption of thermal in the U.S. We have seen a very slow start in a transition toward visible light, which we feel has been primarily due to the limited plate availability and choices. There are far more choices in the thermal plate arena, with strong competition between plate manufacturers spelling good news for the end user. External-drum, 830nm thermal technology also brings the promise of more "processless" plate choices.

Joe Luckett, product marketing manager/CTP devices, Creo-Scitex:
CreoScitex is firmly dedicated to moving forward with thermal as a proven imaging technology. With thermal and our SQUAREspot imaging technology, we offer a level of process control that can't be achieved with violet. The technology also can offer the flexibility of being able to image plates, film and proofs with the same device.

We think thermal can fit all applications, which is why we are introducing entry-level platforms offered at a price point that will make CTP a reality for all customers. The platesetters borrow much of their design from existing systems, but lack some capabilities of the fully featured models.

Efrem Lieber, vice president/sales and marketing, Presstek Inc.:
Among our requirements for a CTP technology are that it not involve chemical processing, not be variability inducing and fit the markets we serve. Therefore, we currently don't see any technology trends that would lead us to anything but thermal imaging.

CTP must go down market, but the system requirements are different for smaller plants. Our technology scales down economically very well, since the tremendous amount of power we put on the surface of the plate gives us the flexibility to image a wide variety of materials.

William Schulin-Zeuthen, currently president and CEO of Purup-Eskofot, to become CEO of BPE:
Since our platesetters support the widest variety of lasers (including violet and thermal) and the laser unit can be changed at any time, we don't tie a customer to a particular type of plate. Our violet-diode implementation of the PlateDriver is the fastest eight-page commercial CTP device on the market.

Violet systems will be cheaper than other lasers when you look at the total cost of ownership. They will take market share away from 830nm thermal systems. We are glad to see Heidelberg and others introduce violet systems because, in doing so, they also are endorsing internal-drum imaging.