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REACHINGHOW DOES A BOXMAKER WITH ‘STANDARDQUALITY’ FLEXO PRINTING EQUIPMENT BREAK INTOTHE GROWING MARKET FOR ‘HIGH QUALITY’ FLEXO?

Koen Verplanke

Warren Bird

Anthony Whiteside

Hakan Pfeiffer

Erik Marjo

André Göpfert

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H igh quality (HQ) flexo post-print is boomingthroughout the corrugated industry, withreport after report describing how boxmakers

around the globe are making existing contracts moreprofitable, are gaining new work, or are exploiting newmarkets — all by improving the quality of their flexopost-print. As a trend, HQ seems not to be restrictedto one part of the world, with the emerging markets ofthe Middle East, South Asia and the Far East being justas much a part of the change as the Americas andEurope. But what changes do boxmakers need tocarry out if they want to start producing high qualityprint and so tap into this boom? Should they buy newequipment or upgrade existing machines? Do they go

in-line or off-line? And what do they need to considerwhen it comes to pre-press, inks, and substrates?Here, a group of key suppliers of flexo pressequipment and consumables give their views on whatto consider when going HQ.

Fertile hunting ground“Flexo always used to be the ugly step-child of thegraphic arts industry,” says Warren Bird, Vice-President of drier and plate technology supplier JBMachinery. “But vastly improved registration, betterprint reproduction, more colours and glosses thatapproach film lamination in their look are all factorsthat, when offered in a single pass operation, make fora very compelling value proposition.” Megastores andsupermarkets are now fertile hunting grounds forsales people offering flexo post-print on corrugated,he explains. “Retail and shelf-ready packaging, point ofsale and point of purchase displays and pallet wrapsare all succeeding as flexo post-print products wherefolding carton, screen print, and plastic containersused to command the greatest share.”

The key to tapping into this market, if you are newto high quality graphics, is being able to bringtogether all the players, says Mr Bird. “You need toorchestrate the various elements to get the best

results. That meansequipmentsuppliers, inkmanufacturers,pre-press,

anilox makers,doctor bladechamber makers,and driermanufacturers.

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There are a lot of variables to be considered if you aregoing to make a success out of HQ print.”

It’s a point that strikes a chord with Hakan Pfeiffer,Head of Bobst Group’s sheet-fed business, whichencompasses both the Bobst and Martin flexo pressbrands. “It’s not just about engineering machines thatare capable of high quality graphics. A vital elementfor press manufacturers like us is that we need towork with the suppliers of other key components tohelp optimise the flexo printing process and push theboundaries of what can be achieved. HQ printing is asystem. Yes, the machine is very much at the heart ofit, but it is important that we work with the suppliers ofanilox rolls, repro systems, driers, substrates andinks, to make sure that we understand the latestdevelopments in each of their fields. Only in that waycan we make the most of the capabilities of ourpresses.”

Mr Pfeiffer also says that it is important for pressmanufacturers to work with their customers’ localsuppliers to help them get the best results. “It’ssomething we do with customers all over the world, onboth new and old machines, because we see our jobas helping boxmakers achieve the very best quality ofprint they can, hour after hour, day in day out, whenthe machine is new and long after.”

Antony Whiteside, Managing Directorof doctor blade chamber specialistsAbsolute Engineering, agrees thatsucceeding in the high quality post-printmarket means achieving consistentlyexcellent print, and that it should be on apar with more established processes.“Anyone getting into HQ will be competingagainst litho printers, screen printers,and increasingly with digital printers, allof who follow recognised colourconsistency standards. As a result, a lithoprinted box on the supermarket shelfmade by one manufacturer is impossibleto distinguishfrom one madeby a differentmanufacturer.They will have thesame colourconsistency, thesame colourdensity and thesame quality ofprint.”

Mr Whiteside says that as an industry, corrugatedneeds to take such standards on board. “You hearnothing about standards in the flexo world, yet theyalready exist in the form of ISO 12647:Part 6, theflexo equivalent of the standards that litho, screenprint and digital printers are using. This standard tellsboxmakers what they need to look at to achieve HQprint, especially in controlling the consistency of theink in the system, without which you can’t getanywhere near HQ.”

Do boxmakers make good printers?With no widely used standard for flexo printing, whatpasses for HQ flexo print differs around the globe,says André Göpfert, Managing Director of pressmaker Göpfert Maschinen GmbH. “Approaching lithoquality is a lot more work than just printing in sixcolours. You might produce a beautiful milk tray withtext and lots of colour, but it won’t be a high graphicsproduct unless some thought and effort has gone intothe repro, the plates and the choice of anilox.”

Mr Göpfert says that repro, in particular, needs tobe addressed by anyone moving into this market. “It’snot just about the hardware. For me, you can’t achievehigh graphics unless you are running CMYK with a

screen of above 48 lines per centimetre.There is a lot of exciting work beingproduced in Germany and Europe in thissort of range, but elsewhere in the worldthe same levels of quality are yet to bereached.”

This difference in standards presentssome risks says Mr Göpfert. “It’s verydangerous to approach retailers sayingyou can deliver packaging that is as goodas litho if you have not got all thecomponents right. Some boxmakers havedone this already and failed. It damagesthe reputation of flexo post-print foreveryone, so it is important that

boxmakers spendtime learning howto print highgraphics reallywell.”

Erik Marjo,Group ManagingDirector at PacificInks, says thatthe Far East, andin particular

IT’S VERYDANGEROUS TO

APPROACHRETAILERSSAYING YOUCAN DELIVER

PACKAGING THATIS AS GOOD AS

LITHO IF YOU HAVENOT GOT ALL THE

COMPONENTSRIGHT.”

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China, is a market where demand is advancing rapidlyfor the inks that are needed to print high qualitygraphics on corrugated. “In developed markets, brandowners have more choices — they’ve got litho,screen, and even digital print available to them. It’s notso in China, and we see a lot of work being printedflexo using process because it cuts out productionstages such as laminating.”

But to achieve the high quality graphics they aspireto, boxmakers do need to be much more precise thanwith standard work, explains Mr Marjo. “You can’t justtip and pour the ink, it’s got to be accurately measuredand the viscosity checked at every station. For the sortof CMYK work that can challenge litho print quality youneed to understand densities and there are fourvariables to consider, which makes sixteen things thatcan go wrong if you’re not paying attention.”

M-real Corporation has also seen high growth inAsia as Koen Verplancke, Technical Service Managerat the paper-maker points out. “We’ve seen highdemand for the coated papers that are needed forhigh graphics work from the USA, Europe andparticularly from Asia.” This growth in demand forcoated papers has prompted the company to setaside €16 million to upgrade its Kemi mill in Finlandduring the autumn of 2011.

Mr Verplanke says that boxmakers need to behonest with themselves about what they can achieve interms of high quality print. “It’s relatively easy toproduce good quality pre-print these days, but highquality flexo post-print relies on a lot offactors ranging from the machine to thepaper. Boxmakers need to accept that ifthey compromise on any of these factorsthey may not be able to go as far as theywould like.”

New press or old?The first question most boxmakers will askif they are considering a move into themarket for high graphics flexo post-print is‘will I need a new press?’

“It depends on your existing equipment,”says Bobst Group’s Hakan Pfeiffer. “We havecustomers who are very successfullyproducing high quality graphics, and winningprint awards for their work, using older Bobstand Martin presses that we have helped themto upgrade. But there are clear benefits toinvesting in a new press like a Masterflex or aMartin 924 FP. Firstly there is the accuracy of

register on the latest generation machines which, withdirect drives and proactive register systems, meansconstant register even with warped board. Then youhave better ink systems using peristaltic pumps whichkeep the viscosity of the ink at optimum levels, withminimal waste. It all gives you reproducible quality timeand again.”

Starting the job with each print unit in perfectregister, and staying there at all speeds, is absolutelyvital when printing high graphics, says Mr Pfeiffer.“Something like the ‘Start & Go’ system on ourMasterflex-HD presses can be the operator’s bestfriend during the start up of the job because it sets theregistration and skews print elongation automatically ifneeded, all with only a few sheets. Photocells at theinlet of each print unit keep the registration perfect,while systems like our iQ300 quality device monitorevery sheet produced for all sorts of defects. Finally,you can expect the running speed of a new press tobe higher than that possible with an upgraded oldermodel.”

André Göpfert agrees that reproducible quality isthe main requirement for high quality post-press flexo.“Using servo drives directly on each shaft throughoutthe machine means you have accurate adjustment ofposition. A system like the computer controlled‘Running Register Adjustment’ on our Ovation line usesdirect drives to keep register and we also use flat,high friction belts to keep the sheets in position. It isalso important to control the ink and to maintain thebest temperature to ensure consistency.”

IT’S RELATIVELY EASY TO PRODUCE GOOD QUALITYPRE-PRINT THESE DAYS, BUT HIGH QUALITY FLEXO

POST-PRINT RELIES ON A LOT OF FACTORS RANGING FROMTHE MACHINE TO THE PAPER.”

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There is also no doubt in Mr Göpfert’smind that quality inspection is vital whencompeting with processes such as lithoprinting. “There is a high demand fromusers for 100 per cent inspectionsystems, especially from our high-graphicscustomers who are competing with lithoprinters.”

JB Machinery’s Warren Bird says thatthe ability to dry the print on the boardeffectively is one of the keys to improving quality,whether it is on a new press or an upgraded one. “Mostnew machines purchased today will have driers specifiedfrom the very beginning, rather than being added on asan afterthought,” he explains. “Equally, we have carriedout a lot of projects in recent years to retrofit driers tomachines where the customer wanted to run fasterand run high graphics work. As long as a machine hasvacuum transfer then we can install driers throughout,while a dedicated dwell section or a wide bodiedprintdown lets us install UV in conjunction with IR.”

Beyond the pressWhether the press is a new line or an upgraded one,the choice of ink application system is critical, saysAnthony Whiteside of Absolute Engineering. “Firstly, ithas to be a chambered doctor blade system. Rubberrollers simply cannot achieve the quality needed todayand most boxmakers are already using chambereddoctor blades anyway. The critical questions to askare: Will they deliver consistency of ink? Will they cleanup effectively? Will the doctor blade changes be quick?Will they lose a lot of ink? ”

Mr Whiteside says that the shape of the doctorblade chamber and the materials it is made from arethe keys to achieving high quality print. “You need achamber that is designed to move the ink in aconsistent manner with all of the available ink reachingthe anilox; otherwise you get ghosting and patchiness.Also, the ink that has not been applied to the aniloxneeds to be expelled within one cycle, so again the

design of the chamber is critical here.”The choice of materials for the doctor blade

chamber makes a difference to both its effectivenessand the on costs of the printing process, as MrWhiteside explains. “Using a material like carbon fibrefor the doctor blade chamber can really help with thequality of ink delivery because its high surface tensionallows the ink to move around more freely. Also,because it repels the ink from itself, a chamber madefrom carbon fibre won’t corrode like metal and caneasily last 15 years.”

When it comes to the ink itself, Erik Marjo of PacificInks says that the rheology needs to be different forhigh quality print. “Because you are applying it to acoated substrate, and will certainly be drying it aswell, you only need to lay down a thin film of ink. That’s

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very different to standard type flexo printing.”Pacific Inks has brought technology gained from its

successful work in the pre-print market to flexo post-print, says Mr Marjo. “Ink pigments have to be milledreally finely if you are going to ensure good entry andexit of the ink on fine anilox rolls. We have to do thesame for ink that will go through digital inkjet nozzles.So we’ve invested heavily in high energy mills capableof reducing pigments from ultra fine particles to nanosized. This technology produces strong, brilliant, vividinks that yield bright colours on lightweight corrugatedliners, giving you a thin film of ink that dries quickly athigh print speeds.”

But bearing in mind that few boxmakers will berunning high quality graphics on every job, and so willneed different types of ink, Mr Marjo says that findinga clever ink making system is essential. “It’s importantto have the right ink for the right job, especially if youare working with fixed parameters such as thecapacity of the anilox rolls. With systems like ourAccubatch, boxmakers can pick and choose the typeof ink they use. It uses the concentrated ink pigmentsand then creates the right formula for the type of jobin hand, using a range of technical varnishes.”

Hickeys outAnother factor that JB Machinery’s Warren Birdbelieves is important inachieving high quality flexo printis the continuous removal ofhickeys from the printing plates.“It’s a problem the industry hasfaced for ever. Boxmakersconstantly have to wash theplates to remove hickeys. Onhigh quality work, using highlycoated papers, there is lessdust for sure, but nowboxmakers can also havecontinuous hickey removal withsystems like our Kleenplateunits which are a valuable toolfor every type of flexo print, butparticularly for high graphics.”

Koen Verplanke from M-realagrees that coated papers havehelped reduce the problems associated with dust andadds that what boxmakers need as much as anythingfrom their paper is consistency. “The papers that thesubstrate is made of need to be coated of course, butthey also need to be consistent in both size and

structure if they are going to be reliable during boardmaking and also later on during printing. Papers likethe Kemiart range, which are made using virgin fibres,have that profile. What the boxmaker needs issomething that is strong and is almost like a foldingboxboard grade so that brand colours can beconsistently repeated from one job to another.”

He also points out that when boxmakers are firstexploring the high graphics market, usually with anolder machine, they may benefit from using anintermediate grade like Kemiart Ultra. “It will give theprint a bit of gloss and extra definition while theboxmaker finds customers for high quality work. Thenwhen they upgrade their equipment or buy a newpress, they will be ready for something like KemiartGraph.”

In-line or off-line?But which configuration is best — an in-line solution oroff-line? André Göpfert says that 80 per cent of themachines his company supplies are specified by theircustomers as off-line. “The machines run faster thanwhen they are in-line with a flat-bed diecutter, andprinting can continue even if the flat bed has stopped.It also means that the machine can run in a dust freeenvironment where the operator can concentrate onlyon the printing. We do supply in-line machines with a

rotary die-cutter where therotary keeps up with thespeed of the printingmachine, but we recommendair management for highquality flexo using this.”

Bobst Group’s HakanPfeiffer says that the choicedepends on the boxmaker’smarkets — both the onesthey have now and the onesthey hope to access. “Off-lineis the most widely usedconfiguration among ourcustomers because it meansfewer interruptions toproduction and less dust. Butwe do have Bobst and Martincustomers very successfully

running high quality graphics on flexo presses that arein-line with either a flat bed die-cutter or a rotary unit.We believe that by having various options open tothem, the boxmaker has the best possibility to choosea configuration that suits them.” �