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○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○A vision becomes realityDirect laser engraving of elastomer plates and sleeves for flexographic printingand gravure cylinders – A report on the beta installation at 4PackagingAn international audienceof specialists acceptedinvitations to the openhouseevent.ANSGAR WESSENDORF___________________________________________________________________________Over the past decades, there have been numerous attempts to makegravure cylinders through contact-free removal of material. Due to allkinds of technical and/or economic factors, however, none of thesesystems succeeded in making any significant breakthrough. Innovationssuch as Crosfield’s laser engraving system 700 or the ElectronBeam Gravure (EBG) process either never reached the market or playedno significant role in gravure cylinder manufacturing. Until recently,industry experts were still of the opinion that direct laser engraving incopper requires too much energy, making it unsuitable for gravurecylinder manufacturing. With the arrival of Cellaxy, the new laserengraver from Hell Gravure Systems, they will now need to reconsider.At the end of June 2006, HellGravure Systems invited over200 visitors to 4Packaging in theGerman town of Dissen. All theworld’s top names in gravure cylindermanufacturing were there to gettheir first look at the direct laserengraving of copper gravure cylindersin one of the most cutting-edgeand productive fully automatic cylindermanufacturing operationsanywhere in the world. In his welcomingaddress, Managing DirectorDr SIEGFRIED BEISSWENGER underlinedhow important the laser project wasto Hell, stating »After eight years ofresearch and development, thestage is now set for the launch ofthis pioneering technology. Nevertheless,electromechanical engravingwill remain the dominant engravingprocess for many years tocome.« He extended a great vote ofthanks to JÜRGEN MÖLLER and GISBERTLUMME, 4Packaging’s Managing Directors,for all they had done to helpmake the event a success.4Packaging has been using theCellaxy laser engraver on a dailybasis under actual operating conditionssince May this year. JAN BREI-HOLDT, PR Manager at Hell GravureSystems, stressed that this was onlythe start of the beta phase and it wasnow primarily a matter of gatheringpractical experience in using thenew technology.Directly into copperThe Cellaxy output device is fittedwith a high-power multi-kilowattlaser which, for the first time, providesthe power required to engravea copper surface. The continuous(non-pulsed) laser has a wavelengthof 1060 nm. It engraves cells directlyinto the copper surface with aresolution of 2540 dpi (1000 l/cm)and is controlled with a 3D RIP. Thewriting principle is thus similar tothat of an offset platesetter, witheach cell being formed from a matrixof, 16 x 16 laser dots, for example.In contrast to offset, however,the laser can vary the intensity and,consequently, the depth of eachindividual laser dot. This enablesthe engraving screen to be freelyadjusted in terms of screen resolution,dot shape, depth, and cell-towallratio. Instead of the two-dimensionalscreening in offset printing,Hell has succeeded in achievingthree-dimensional screening. Inaddition to typical, conventionalgravure screens (with variabledepth), autotypical screens (withvariable area) and semi-auto-typicalscreens (with variable area anddepth), three-dimensional screeningcan also display combinationsof these screens. Unlike electromechanicalengraving, screening withthe Cellaxy system makes it possibleto separate the write resolution andengraving screen, thus increasingthe volume of ink transferred andcreating a high print density. Thisfeature will allow gravure cylindersto be adapted to very specific conditionsin future.Smooth contoursand high print densitiesThe laser’s high engraving resolutionof 2540 dpi results in a similarlyhigh contour definition. The sawtootheffect typical of electromechanicalengraving is a thing of thepast. Having said that, other technologiesto lessen this effect arenow also available, for example antializingwhich counteracts the effectby setting edge cells. In order toobtain perfectly smooth edges,however, half cells are required. Inelectromagnetic engraving, this canbe achieved using the specialXtremeEngraving process, throughlaser imaging/etching or throughdirect laser engraving in copper.The Cellaxy direct laser is idealfor applications in the cigarette,labeling, and pharmaceuticals sectors.The Cellaxy is initially beingused at 4Packaging for linework inthe cigarette sector, which requireshigh colour densities and ultrafinetext and graphics. With this new© by G&K TechMedia GmbH · D-79261 Gutach · www.flexo-gravure-international.com

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○Left:The Cellaxy was the focusof interest.Right:A real eye-catcher – theworldwide unique Inlinecylinder store.technology, the strengths of electromechanicalengraving and thecompany’s reproduction technologyand cylinder production knowhow,4Packaging is looking to gaina firmer foothold in the cigarettemarket.Control and productivityThe laser is controlled using a Maccomputer with RIP technology fromArtwork Systems and a screen controlsystem from Hell. The TIFF filesare processed in the RIP and theengraving screen information isadded. This newly developed technologycurrently enables theCellaxy to operate at an engravingspeed of 0.6 m 2 /hour, matching theproductivity of electromechanicalengraving.High level of automationand impressiveproductivityThe fully automated AutoCon productionline installed at 4Packaging,a joint project of Kaspar Walter,Bauer and Hell Gravure Systems, isdesigned for a daily throughput of50 to 60 cylinders, seven days aweek. In addition to the direct laserand four HelioKlischograph K500engravers, the production line incorporatestwo chromium-platingbaths and two degreasing andcopper-plating baths. There are alsosystems for geometrical processingand for polishing and grinding ofthe gravure cylinders. Kaspar Walter’sSlimline baths are so narrowthat twice the normal number ofbaths can be placed (back to back)on the same footprint. The individualprocessing stations are loadedand unloaded quickly using Bauer’scompact monorail crane at a maximumspeed of 120 m/min. The parametersfor each separate cylinderare stored in the master computer.Operators have access at any timeand modify the paraments if necessary.Inline storeIn addition to the Cellaxy directlaser, the audience of specialists alsogot their first look at Bauer Logistik’sInline cylinder store, a furtherhighlight of the event. Forming anintegral part of the AutoCon line,the store holds 130 cylinders andthis capacity will increase to 260cylinders from November 2006.Only thanks to this space-savinginnovation is it possible to havetruly non-stop production line operation.The storage system allowssemi-finished gravure cylinders tobe buffered ready for further fullyautomatic processing, which is notpossible with cylinder trolleys.The store consists of two V2Asteel side sections with round holesinto special plastic supports are fitted.The gravure cylinders are storedin the Inline rack in such a way thatpart of their face surface rests on thesupport. They are removed fullyautomatically, the rack serving unitpicking up the cylinder by its face,extracting it sideways from itsstorage location and then transferringit to the monorail crane. Thecrane transports the cylinder to theappropriate processing station onthe line according to the instructionsentered.An up-and-comingcylinder engraverFounded in 2000, 4Packaging iscurrently one of Europe’s mosttechnically innovative and rapidlygrowing manufacturers of gravurecylinders for packaging printing. InDecember 2005, the company movedinto its new production and administrativepremises with cuttingedgeinstallations and equipmentfrom Hell and its partners for thefully automatic manufacturing ofgravure cylinders. Key factors in thecompany’s success are its flathierarchy and the young, committedteam. Naturally, 4Packaging isalso involved in other activities,Technical data: Inline cylinder storage system by Bauer Logistik● Fully automatic storage and transport of gravure cylinders, specially designed forKaspar Walter production lines● Stores shaft and hollow cylinders● Max. face length: 1700 mm● Max. total length: 2300 mm● Max. circumference: 1000 mm● Max. weight: 400 kg● 5 separate storage compartments per tower● Small footprint (20 cylinders per meter of line)● Dimensions: 8800 x 8000 x 3000 mm, free height up to 3000 mm● Max. storage height: 2570 mm● Lifting speed: > 30 m/min.● Touch-panel control● Optional trolley stations (including trolleys) loaded directly by the rack servingunit● High safety/security standards:– Installation is protected against unauthorized entry– Dual »compartment occupied« sensor system prevents collisions– »Occupancy sensors« in the telescopic arms of the rack serving unit recognizethe risk of an imminent crash when cylinders are being loaded and unloadedand make the installation safe.© by G&K TechMedia GmbH · D-79261 Gutach · www.flexo-gravure-international.com

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○Left:Each cell is formed from alarge number of laserdots. Modulated laser intensitiesallow differentengraving depths.Right:The Cellaxy can easily beincorporated into existingproduction lines and thereare no special demands interms of the engravingcopper.such as the manufacturing of cylinderblanks, changes to cylinder diametersand other steelwork on thecylinders.ConclusionWith Cellaxy, Hell has succeeded inmaking a long sought-after breakthrough,realizing the vision of laseringcells directly into the copperlayer of a gravure cylinder withouthaving to make changes to the electroplatingprocess. In cooperationwith 4Packaging, Hell will use thebeta phase to gather practical experienceand further advance the developmentof the direct laser. Thisprocess with its high-resolution engravingwill play a key role infuture, in particular for high-qualitypackaging (cigarettes, labels,pharmaceuticals, security etc.).Electromechanical engraving isa sophisticated technology. It isconsidered to be representative ofthe high standard of modern cylinderpreparation and will continue tobe used for the majority of packagingcylinders. Here too, Hell hassucceeded in showing the way forwardwith the K500. Over 400 ofthese engravers have been soldworldwide to date.4Packaging’s fully automaticAutoCon production line includesfour K500 engravers in addition tothe Cellaxy. The line’s non-stopoperation seven days a week ensurescost-effective cylinder production.Sophisticated, tried-andtestedtechnologies and developmentssuch as Slimline baths, themonorail crane and the Inlinecylinder store have helped create aCellaxy direct laser system from Hell Gravure SystemsDimensions of basic unit: 5740 x 1960 x 1520 mmWeight:10,000 kgHollow cylinderFace width:400–2200 mmCircumference:200–1400 mmWeight:Max. 800 kgCylinder mounting:Pivot mountsShaft cylinderFace width:400–2200 mmIncluding shafts:1100–2900 mmCircumference:200 –1400 mmWeight:Max. 800 kgCylinder mounting:Three-jaw chuck/pivot mountsgravure cylinder perparation processthat requires virtually no humanintervention.■HELL Gravure Systems GmbHPhilipp-Reis-Weg 5 · D-24148 KielTelefon +49-(0)431-2377-0 · Telefax +49-(0)431-2377-1235 · www.hell-gravure-systems.comReprinted from FLEXO & GRAVURE INT'LG&K TechMedia GmbH · Am Stollen 6/1 · D-79261 GutachTelefon +49-(0)7685-918110 · Telefax +49-(0)7685-909011 · www.flexo-gravure-international.com© by G&K TechMedia GmbH · D-79261 Gutach · www.flexo-gravure-international.com