the 05/14/2008

Print kit has packs of appeal

Heidelberg Printing Machine While Drupa is mainly targeted at the commercial print sector, there is plenty to interest

the packaging printer. Demonstrations of the latest kit in the three main print processes will be foregrounded, together with

plenty of interesting developments in post-press and value-added finishing. At Drupa 2004, packaging experts predicted that

at the next Drupa the flexographic process would match other packaging print processes for quality and cost-effectiveness.

Four years later, it’s debatable whether that has actually happened, but Drupa will certainly be a showcase for several

developments that promise to push flexo closer to pole position in the near future, taking market share from both offset and

gravure. The Flexo4All strategic alliance – 19 of flexo’s most influential suppliers and manufacturers from around the

world – will promote flexo for packaging at Drupa. Its members read like a ‘who’s who’ of the packaging industry: Bobst,

DuPont, EskoArtwork, Fischer & Krecke, Gallus, Sun Chemical, Uteco and Windm?ller & H?lscher among others. The group, which

is the latter-day incarnation of DuPont’s 20-year-old Flexo – The Alternative initiative, will seek to encourage networking

within the flexo industry, connecting competence and promoting flexo as “the best technology to satisfy all printing needs”

. DuPont’s EMEA marketing manager for packaging graphics, Pier Luigi Sassanelli, believes that flexo is “ideal for almost

all substrates, all segments, all applications and all budgets, and more.” Versatile flexo There have been improvements in

flexo technology over the past five years – a massive boost with the introduction of digitally imaged plates, together with

parallel improvements in inks and anilox systems. It is certainly a versatile process, with the ability to print onto

absorbent and non-absorbent, flexible and rigid substrates. It is also fast, with speeds of 500 metres per minute common. Its

claim to cost-effectiveness rests partly on the relatively inexpensive levels of investment compared with offset and gravure,

and partly on the fact that some finishing processes can be added inline, eliminating inter-process handling costs and time.

There is even the claim that flexo presses are more environmentally friendly, although this assertion is not about energy use

so much as the fact the process can use water-based and solvent-free inks. But even with all these manifest advantages,

Flexo4All’s claims to supremacy may remain optimistic, given that the quality of flexo printing has traditionally come a

poor second, or even third, to offset litho and gravure. Flexo print is known to suffer from fluting and ghosting due to

poorly formed dots on the printing plate. The problem is that an ordinary flexo platemaking process produces dots that look

like a range of mountain peaks, due to oxygen that is hard to eliminate from the polymerisation stage of the process. A peak

-shaped dot does not transfer ink precisely from its top face because the peak compresses during contact with the substrate

and transfers ink from the sides as well as the pointed tip – hence the ‘fluted’ effect. To combat this, most studios

apply a tonal curve that effectively makes the smaller dots bigger and the bigger dots smaller. But the effect of that is to

allow only a limited tonal range to be printed. However, several initiatives are underway to combat the limitations of the

flexo platemaking process. The aim is to eliminate oxygen, thereby creating a plate with a flat-topped dot that can reproduce

a full range of grey levels. The three companies working on this process have taken different approaches. US trade

platemaking house PRP Flexo has a proprietary process for supplying flat-top-dot plates to other flexo printers. Kodak offers

a complete system encompassing Flexcel digital plate, thermal top layer, platesetter, laminator and even a workflow. UK

flexible packaging film printer TCL Packaging’s proprietary Fotoflex process has focused on the screening process with

additional adjustments on the press for optimum results. UV flexo is also an established technology, particularly in the

labelling sector. The process uses minimal Volatile Organic Compounds (VOCs) and gives faster makereadies, besides doing away

with the need for pressroom climate control, thereby cutting energy costs. And because of brighter colours and superior

scuff, fade and chemical resistance, UV flexo has also gained wide acceptance by packaging buyers. Gidue will be at Drupa to

show off its UV flexo mid-width webs; likewise Carint, Edelmann, Focus Label Machinery, KPG Europe and Muller Martini all

have offerings in the UV flexo area. Windm?ller & H?lscher is staying on after its appearance at Interpack to show the

Miraflex C press, a common-impression flexo machine with eight to 10 colour decks and printing widths from 1-1.45m.

Developments in ink (see box on page 51) are also pushing up flexo’s quality, cost-effectiveness and green credentials.

Fischer & Krecke’s WetFlex will be shown: entirely without inter-deck drying, the WetFlex uses inks developed by Sun

Chemical that allow wet-on-wet printing with only a single drying shot delivered last in the line by an electron beam (EB)

curing unit. Digital delights Digital technology made its first forays into the packaging sector more than a decade ago, with

the launch of HP Indigo’s first web-fed label press. The uptake of digital has since accelerated to make it the sector’s

biggest growth area. Digital’s impact on the packaging sector has been partly due to its substrate flexibility – everything

from light-gauge board to flexible films can be printed digitally – and for its variable data capacity, which no other print

process can replicate. In the short-run arena, digital continues to take work from offset and gravure. The technology also

continues, through its innovatory attributes, to create entirely new markets that simply did not exist before – such as

metal can decorating in runs as short as one, exemplified by Impress’s dPrint digital system. Digital’s original capability

for only a limited-gamut colour reproduction from four-colour toners or inks initially held it back in packaging, with the

sector’s demand for vivid and precisely-matched colours. But this year’s Drupa will demonstrate that this gap has been

closed: HP Indigo, Xeikon, Océ and Canon now all number four-colour-plus printing among their machines’ capabilities. Many

are hailing this year’s exhibition as ‘the inkjet Drupa’, and while most of these developments will concern commercial

printers, packaging printers will be particularly interested that several wide-format digital inkjet manufacturers have

turned their attention to the packaging market, offering a press for the purpose. Raster Printers, of Bicester, has targeted

carton printers with its new Daytona H7000UV wide-format flatbed that can print onto any rigid or flexible material at speeds

up to 29m2 per hour. If packaging printers can find a use for this type of technology, other wide-format printer

manufacturers may follow: there are applications in short-run carton work, model-making and variable-data packaging.

Cambridge-based Tonejet also has designs on the digital packaging sector with its new wide inkjet head, which it intends for

food and drink carton print. Meanwhile, there are fringe developments of inkjet technology that are directly aimed at the

packaging sector. At Drupa, Nilpeter will demonstrate Caslon, a modular digital print solution for labels and narrow web

packaging using four-colour process UV inkjet technology. Caslon can be integrated into Nilpeter’s conventional flexo press

lines, or can function as a stand alone roll-to-roll system. Developed jointly by Nilpeter and FFEI, Caslon uses the latest

Xaar 1001 printheads. This variable drop (greyscale) printhead features Xaar’s patented Hybrid Side-Shooter platform with TF

Technology designed to produce dynamically variable drop sizes needed for fine detail and readable small text and smooth

tones reliably and consistently in single-pass applications. Inks manufacturer Sun Chemical is also getting involved in

hardware, with its new SolarJet UV flexo label press for short runs: the press is intended for runs of up to 10,000 labels

for the pharmaceutical and health and beauty sectors, and uses Xaar 760 inkjet printheads. On the non-inkjet digital score,

there are plenty of new packaging-led developments at Drupa. HP will show a new web-fed Indigo for label and packaging work,

the ws6000. This big brother to the well-known ws4500 is designed mainly for high-volume customers, printing at up to 30

metres per minute. Like other HP Indigos, the ws6000 can print up to seven colours, together with a new improved white, which

label and flexible packaging printers will find useful. Xeikon will also launch a new web-fed press, the 8000, capable of

printing onto a wide range of substrates including flexible films and self-adhesive label stocks – this builds on the

corporation’s initial foothold in the digital packaging market through the original 6000 press. The slow but ineluctable

decline in CD and DVD sales in favour of downloadable digital content is responsible for a corresponding decline in machines

for printing CD/DVD packaging. Here, however, digital press manufacturers are experiencing growth in sales as runs become

shorter and have less lead time: printers specialising in this area are turning their attention to digital as a cost-

effective answer to a changing market demand. An interesting fusion between workflow and digital print will be in evidence at

this year’s Drupa, with front-end controllers for digital presses being shown by workflow developers: EskoArtwork’s Labels

and Packaging SmartStream PrintServer has been developed especially for HP Indigo’s digital presses, and there is evidence

that the web-to-print boom, riding high in commercial print, may also find some limited, customer-specific footholds in the

labels and packaging sector in the next two years. Finishing school The post-press sector looks a little different at Drupa

this year, due to the continued drive among manufacturers to keep as much finishing as possible inline to the press, thereby

eliminating handling time and costs, together with floorspace and the extra capital investment in separate post-press

machines. This trend has always been marked among narrow web and flexo press manufacturers, and this year’s Drupa backs up

the point with new launches from Gallus among others, which link die-cutting units inline for integrated production. Sheetfed

litho press manufacturers could be said to have taken a leaf out of the flexo press manufacturers’ book: Komori is one of

several press manufacturers to be launching a new sheetfed press with inline cold foiling, UV coating and embossing at Drupa.

Like all inline processes, the added-value units on the Komori machine slow it down by about 15-20%, but that still makes the

processes much cheaper than offline equivalents. Other sheetfed packaging presses that aim to incorporate processes inline

include Heidelberg’s new super-size 145 and 162cm presses, MAN Roland’s new size 7, 7b and 8 presses, and KBA. The theme of

automated, integrated production is continued into standalone post-press machinery. Heidelberg will launch a new folder-

gluer, the Diana X 115: not only is the line capable of processing 200,000 cartons per hour, it also boasts a new auto-feed

and a delivery packer. Die-cutting is also moving towards integrated production, with a raft of machines newly extended to

incorporate functions such as embossing and foil-blocking in a single pass – these include Heidelberg’s Varimatrix 105CSF

die-cutter with foiling and embossing and Blumer’s Atlas label cutters, which will be hitched inline to a label press.

Chinese manufacturer Masterwork will launch a new ‘hybrid finishing line’ – effectively a die-cut, foil and stripping line

– while Saroglia will show an integrated die-cutter, foiler and embosser. Ehret Control will show a label finishing line for

die-cutting or strip cutting. There also appears to be a continued trend towards short- and ultra-short-run cutting at Drupa.

EskoArtwork will show Kongsberg XP digital cutters, while Saroglia will also show a new laser cutter for packaging

applications. Elsewhere in post-press, technology developments focus on minimising makereadies and the reduction of waste.

Bobst, famously taciturn about its exhibition launches before any show opens its doors, has said that it will launch a new

generation of its Power Register technology – a dynamic registration control software that uses photocell technology to

reduce unplanned stops due to misregistration of the die to the sheet. Also of interest is Japanese sheetfed press

manufacturer Shinohara’s Casting Curing Unit (also known as C2): this offline UV coater flash-cures a varnish by projecting

UV light through a patterned film to achieve a subtly imaged effect on the varnish, for decorative or security applications.