None of that has stopped all of the world’s biggest wide-format players from developing their own UV machines, and the proportion of display printers now already using, or considering a move to, UV has grown exponentially in the past two years.

DuPont is the newest entrant to the UV market with its Cromaprint 22UV, a 2.2m-wide flatbed/reel-to-reel piezo inkjet – its first wide-format printer of any kind, in fact. Launched 12 months ago, the 22UV has been a big success in its first year, with DuPont meeting sales targets way ahead of schedule. On the back of this, a baby 1.8m Cromaprint is next up for launch in 2007, and DuPont is also promising a wider-than-2.2m Cromaprint some time next year.

Wide format’s future
Cromaprint has been five years in the making, with DuPont having discontinued a range of solvent-based printers at a late stage of development two years ago. Cromaprint business development manager Chris O’Brien describes the decision to go the UV route as “avoiding the me-too” scenario.

“The price of solvent inks is wide, but averages out quite low and, at the end of the day, we are a consumables company – it wouldn’t have been easy to make money,” says O’Brien. “Plus there are a lot of players in that market, and we didn’t want to be just another company selling just another product. We felt UV offered us the opportunity to get in at the beginning of a new wave of wide-format printing.”

O’Brien rates the UV sector as having huge potential: “We think it’s definitely the future of wide format. It’s a slow beginning, but compares favourably with solvent, where growth is almost flattening out.”

He dismisses the higher cost of UV inks as a function of wide-format shops’ relative unfamiliarity with the UV process. “Pound for pound, you get more solvent ink for your money than UV. But when you start to dig behind that bare fact, you quickly realise that the greater cost of UV inks is more than compensated for by ease-of-use factors,” says O’Brien. “For a start, there’s a lot of waste with solvent inks because the nozzles tend to jam up and it takes significant amounts of ink to purge them. They also contain hazardous chemicals, and there are health and safety issues associated with storing and using them.”

Due to the nature of UV polymers – which form a film on the surface of the substrate rather than being partially absorbed as with solvent inks – many believe that a UV printer can print onto a much wider range of materials than solvent printers. So, when it comes to inks, O’Brien says any small extra cost gives “a big set of advantages”.

Right balance
In developing the Cromaprint, DuPont targeted a working speed of 25sqm per hour. This is the average production speed for top, or almost top, quality on the UV printers already on the market, and allows DuPont to tackle the market carved out by Nur, Inca, Durst and ColorSpan among others. But the company was also conscious of the need to control the capital cost of the printer, and the Cromaprint is pitched as a three-way balance between cost, speed and quality: “Our machine isn’t the fastest, and it’s not the lowest cost, but we’ve kept those aspects in balance with the quality,” says O’Brien.

The Cromaprint uses 14 Spectra Galaxy printheads – they are considered as consumables, and O’Brien says users can expect to be replacing “one or two a year” on average. Head replacement is covered by DuPont during the 12-month warranty period, and after this, the company offers a two-tier maintenance contract, one tier of which offers cover for all replacement printheads.

The Cromaprint has been so named for a good reason – it shares in the front-end colour management software and know-how built up by DuPont’s years of experience with Cromalin and Digital Cromalin. Cromaprint’s RIP, based on an Adobe CPSI, PostScript Level 4 engine, is called Cromanet, and it also drives DuPont’s digital proofers. Cromanet uses a lab-based colour model and applies this using spectral-based calibration, ie the system measures actual colour rather than just density of ink layer, keeping within the colour-space tolerance.

Cromanet has been extended for use with Cromaprint – a good proportion of what dictates a colour output is the substrate it’s printed onto, and one of the big USPs of Cromaprint is its range of substrates (as opposed to Cromalin, which uses special DuPont stock).

Top quality colour
The R&D team has spent six months working out profiles for different types of material, both rigid and flexible, used in wide-format markets. The colour management techniques embedded in Cromanet go a long way to prevent any colour gamut issues, and for the rest, O’Brien says the inks are based on Cromalin equivalents, “which can reproduce 96% of the Pantone range” using an extended CMYK inkset incorporating light magenta and light cyan. Cromaprint also incorporates a seventh colour, a white used to provide a white backing for printing onto coloured substrates.

Makeready is simple and quick. The printhead gantry is adjusted (manually) for the thickness of material being printed, and the material width details are input by the operator. After each overnight stop, the operator must run a priming sequence for the inkjet heads, and an alignment test to make sure all the nozzles are aligned. This procedure takes around 15 minutes in total.

The Cromaprint’s changeover between reels and rigid sheets is straightforward – any flexible material on the bed is reeled back using the unwind, while the support beds are attached for rigid sheets. There are no automatic load/unload facilities for rigid sheets. DuPont recommends that the Cromaprint is not left to work unattended, and it’s envisaged that one or two operators, depending on the weight of the materials being printed, will always be in attendance.

The Cromaprint comes as a bundle, with print engine and Cromanet colour server. Users must also use DuPont-manufactured inks to take advantage of their extended colour gamut, and third-party equivalents will render the Cromaprint warranty (or the service contract that replaces the warranty after a year) invalid.

In terms of users, the Cromaprint’s width puts it squarely in the indoor market: display graphics, exhibitions and interior signage, and point-of-sale. But where size allows, Cromaprint can also print for outdoor applications, aided by the appropriate lamination for harsher environments. The first installation went into Nottingham-based Viva Imaging back in October last year. Viva plans to target traditional screenprint applications for both indoor and outdoor use.

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SPECIFICATIONS
Resolution 800x600dpi
Speed 43sqm per hour (at 400dpi)
Number of colours 6+ white
Max media width 2.2m
Max material thickness 51mm
Price £139,809 (with Cromanet colour server)
Contact DuPont 01438 734000 www.dupont.com

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THE ALTERNATIVES
Agfa Anapurna XL
Agfa’s piezo inkjet is a hybrid machine with a dual reel and rigid capacity. It has a lower resolution than the Croma­print, but is faster and offers a larger print area. Users are tied to Agfa’s own UV inks, and the Anapurna has a white ink in addition to the extended-gamut CMYK printheads.
Resolution 363x725dpi
Speed 40sqm per hour
Number of colours 6+ white
Price £140,000
Contact Agfa Graphics UK 020 8560 2131 www.agfa.com

EFI Vutek PressVu UV 200/600
This 2m four- or six-colour flatbed/roll UV printer is popular for photographic work thanks to its 600dpi resolution. Four colours plus white are optional. Vutek rates the machine at 33sqm per hour, which is very respectable. The 1.8m 180/600 model offers up to eight colours and 360x800dpi, but can hit 51sqm per hour in double four-colour mode.
Resolution 600dpi
Speed 33sqm per hour
Number of colours 6, 4 or 4 + white
Price £125,000
Contact EFI 020 8476 7676 www.efi-vutek.com

Durst Rho 600 Basic
The basic incarnation of Durst’s 2.05m wide piezo inkjet is still faster than the Cromaprint printing at the same resolution. Like the Cromaprint, there’s a white option, but the Rho will only print onto rigid sheets up to 40mm thick, as well as flexible materials.
Resolution 600dpi
Speed 40sqm per hour
Number of colours 4, 4 + white
Price not supplied
Contact Durst UK 01372 388540 www.durst-online.co.uk