DJM works on Photonic driven inkjet

Inkjet atlight speedHybrid presses (offset, flexo, rotogravure and screen printing) with inline inkjet printingwould change the future of packaging printing, commercial printing and more. But for now, itdoesn’t have massive impact, partly because inkjet imprints at full speed with hundredpercent register has inevitable drawbacks. DJM is working on a solution with Photonic driveninkjet.Briefly, the goal of DJM's innovationproject is to have the RIP digitallyregister each subsequent inkjet imprintimage with a previous preprint or colorregister. To achieve this, data speed isneeded that comes in the vicinity of 2.5terabytes/sec. Inkjet technologistSteve Knight points out regularly that'in the printing company of tomorrow,it's not about the print engine, butabout the processing speed of datavolumes.’

A dreamThe 25-year-old DJM came into thepicture at Drupa 2016, but also at theGrafische Vakbeurs in Gorinchem(NL). Demonstrations of inkjet imprintson (A3) sheets and envelopes,accurately fed on a vacuum conveyorbelt, were carried out at bothexhibitions; on Drupa even with aperforated stainless steel vacuum belt.At both exhibitions, attention was alsopaid to DJM's roll2roll inkjet printingsystems. At Drupa, DJM demonstratedher 'Dream-Machine' live; a roll2roll fullcolor prototype with Fujifilm Dimatixsamba printheads. In Gorinchem, thiswas done through screenpresentations. Shortly after Drupa2016, print service provider RamonChozas S.A. from Buenos Aires,Argentina (RCA) ordered a 'Dream-Machine' printing system in 43 cmwide roll2sheet version, online with aunwinder, buffer, cutter and stackerfrom Tecnau.

This configuration has been producingtransactional prints at a resolution of1,200 x1,200 dpi for several telecomcompanies since 2017 with 375 ft/min(114 m/min). Everything – includingreal-time ripping and software linksbetween the various systems – iscontrolled from one software platform;the 'Kameleon' system from DJM.In addition, DJM developed thecustomized paper transport with a BSTweb-edge control and a triple webtension control. To prevent the risk ofdamaging the Samba printheads andto maximize uptime, a unit has beendeveloped that can deal withsplices/roll changes. If a splice isdetected, the distance from the printhead to the substrate is increased – bylowering the print web whilemaintaining the web tension – andwere the printing process istemporarily interrupted.

Photonic driven inkjetDJM is now working on the ‘Photonicdriven inkjet’ project, for which thecompany granted an EU subsidytogether with TNO. The EuropeanRegional Development Fund describesfor which this subsidy is granted: 'Themain objective of the project is toregister substrate movements 3-dimensionally and, at the same time,to make adjustments in the control ofthe print module. In this way, theperfect inkjet drop is created under allcircumstances and is positioned in theright place on the substrate. Toachieve this, a measurement

method must be developed to monitorthe substrate and sensors will bedeveloped that can carry out thesemeasurements. In addition, anencoder must be developed that cantake measurements in the X, Y and Zdimensions.' In other words, DJM aimsto ensure that at an imprint speed of1000 ft/min (300 m/min) – on, forexample, previously printed offsetsheets – every inkjet imprint is digitallybrought into register with the offsetimage, regardless of positiondeviations between the preprints. Thisalso applies to the full color inkjet printitself, of which the digital color unitsmust remain in register. This requires,

Drupa 2016: DJM’s Samba ‘Dream Machine’.

Article Graficus September 2018

in combination with a resolution of4,800 dpi and print width of 40 inches(1000 mm), the aforementioned dataprocessing of 2.5 terabyte/sec. Thetotal project value comes toapproximately one million euros. DJMfounder and owner Dick van der Maaltalks about how this project ideaoriginated. 'Thinking about what'snext', I focused on the biggest obstacleof variable hybrid inkjet printing. Printhardware is not the first concern, it’salways the speed of data processing.In a previous project, for example, wehad to recognize an object for T-shirtprints, then convert the deviation andfinally re-rip the repositioned imprint.Initially it seemed to apply exclusivelyfor imprinting non-register importedsheets or flat objects, but now we alsosee comparative issues in hybrid webinkjet imprinting. For example, due tolong web length with axial and radialfluctuations. This puts even morepressure on ultra-high-speedprocessing of large data volumes'.

Opto electronics'In 2010 I heard about Intel'sreplacement of copper to light beams(opto electronics) on microchips.Furthermore, I understood that theEuropean investment program Horizon2020 had defined photonics as one ofthe five key-technologies. Furtherstudying, photonic microchips turnedout to do all kinds of operations basedon light. In comparison to electrons,photons are also extremely lightweight.This offers opportunities to processmuch more information while usingless energy. Not only for processing orsending data, but also for otherapplications, such as sensors.Meanwhile, there is already been a lotpublished on this subject. In theFraunhofer Project Center at theUniversity Campus in Enschede (NL) amachine was developed for theproduction of photonic chips incollaboration with PHIX PhotonicsAssembly and was the first steptowards mass production. Through ourpartner

We need data rates of 2,5 terabyte per second.

DJM’s ‘Dream Machine’ at Ramon Chozas Argentina.DJM’s HP C800 print modules integrated on web finishing line.

TNO we came up with our project ideaat "OP-Oost", the European Fund forRegional Development in Arnhem(Operational Program ERDF 2014-2020 East Netherlands). We are thesecretary of the project and will bepulling the weight. The steelconstruction of the prototype is doneby our "neighbour", Den Oudentechnical services. TNO will assists usin the development into a prototype.The life span of our project is threeyears and has recently been kicked-off.’

Concrete interpretationCurious I take a look at R&D andDJM's mechanical engineering withVan der Maal and his internationalsales director Arwin van Oostveen.There, the required project disciplines– ICT, mechatronics, inkjet processortechnology, measurement/controltechnology and machine construction– are implemented in concrete terms.Van der Maal: 'Fujifilm's Sambaprinthead is one of our starting points,

but the total printing application differsper customer. Print width, job path,inline converting and so on; we neversay 'no' and our systems are alwaysscalable; for example, starting withmonochrome recto verso and laterexpanding to full color. This frame willbe soon transformed to the next'Dream-Machine'.

Founder and CEO Dick van der Maalat Print18 in Chicago.

Article Graficus September 2018

After the first machine for Argentina, thesecond went to South Korea, the thirdto Russia. In the meantime, they aresupplied throughout the world;Germany, the Czech Republic, NorthAfrica, the USA and also in theNetherlands. This company has a high-speed full color inkjet system forprinting envelopes.' In the productionfacility we see a recto verso printingsystem with six thermal C800 color print

modules (CMYK) from HP and printsthe web on two sides. 'This solution issimilar as the one at Paragon CustomerCommunications in Germany. It is aprinting solution for the production ofloyalty programs and mailings. The printmodules use HP's TIJ4 technology,which is also used in HP's T-seriesinkjet web presses. They are perfect forintegration and for full-color imprints,but are restricted to HP's water-basedinks', says Van Oostveen.

Multiple Samba printheads positioned in ceramic print bar.

DJM’s in-house developed printed circuit boards.

In-house engineering of all components. In screen the ink management backplane of Samba print module.

At the engineering department, we seea technician modifying a technicaldrawing of an ink managementbackplane on a computer. 'This is for aSamba print module and is developedin-house mechanically as well aselectronically. One design aspect isthat this ink management is designedto work completely autonomous.' Theink management module is also verysuitable for other printhead suppliers,such as Kyocera. DJM's designphilosophy is based on that developedtechnologies can be applied widely.

’Dream Machine’ under construction.

Assembling the ink management back plane.

Article Graficus September 2018

Printhardware is not the first concern.

Back at mechanical engineering, wesee the ink management system forthe Samba print modules in prefabstage. We can also handle variousprinted circuit boards, all with copyrightnumbers and DJM logos. 'Owndevelopment'; says Van der Maal withproud. 'It is true that we manufactureexternally on our specifications, but webear the ultimate responsibility. That iswhy, for example, we check all solderjoints again microscopically. Thefunctionality is checked thoroughlyduring the endurance test of the finalprinting machine.’

SambaDJM's quest for the most reliableprinthead in the highest print qualitysegment led to Fujifilm Dimatix' Sambaprinthead. Van der Maal: 'in the 1200 x1200 dpi printhead category, theSamba is the best and most reliablepiezo printhead I know, suitable forwater-based and UV inks. Looking atthe installed base and the performancethat Samba printheads

Arwin van Oostveen at Print18 in Chicago.

Future plansPhilosophizing about DJM's plans forthe future in the success of the‘Photonic driven inkjet’ project,

Van der Maal sees the inkjet imprintmarket as the growth domain for it.That is not a new area for us. Takethis project for example for a Russiancustomer. They were looking for anoptimal inkjet imprint solution,integrated on their eight-color DrentVision web offset press. For them wedeveloped the inline Samba printmodule with twelve samba printheadscreating a print bar of 20,3 inches(517mm). Thanks to the high printresolution, this customer can processa wide range of applications frommailing, statements and tickets. At thismoment, they are using severalSamba print modules in 24/7production.’ 'And if DJM's ‘Photonicdriven inkjet’ system should print

sheets or packaging with piecemealpositioning, would that beconceivable?', asking curiously. 'Wewill use this feeder for full-colorimprints of an earlier offset print,' saysVan der Maal, pointing to a large sheetfeeder of the BDT (75x106cm). ‘It hasbeen developed for the packagingindustry and as sheet insert for, forexample, large format offset preprints.We also manage to integrate on state-of-the-art web presses, offset, flexo,rotogravure and screen printing.’‘Andfor full color inkjet imprints on a foldingbox machine or a packaging line tointegrate?’ Maybe promising, but nowtoo early as feasible to close to theresults of our Photonic driven inkjetdevelopment project.’

Samba print module (20,3 inches wide) integrated in web offset press.

This article was originally published in the September 2018 edition of Graficus, a leading graphic magazine.

Text: Jan VroegopPhotography: Jan Vroegop

Article Graficus September 2018

have delivered in Fujifilm's JetPress720 since Drupa 2008 is significant. Inaddition, the parallel nozzle rowsrunning at an angle of 60 degrees arecleverly positioned. Among otherthings to compensate for missingnozzles and reduce cross talk of thenozzles. The Samba's native dropletsizes are also adjustable, varying from10 picoliter to 2.6 picoliter (for photoquality). The next best and moreaffordable alternatives are for exampleHP's thermal printheads, Kyocera orMemjet.’