Lexmark International inkjetprinting manuale d’uso

inkjet printing TECHNOL OGY, INKS AND P APER F OR M-r eal Digital imaging[...]

2 Inkjet T echnology: an overview 3 Heads, Modes and Nozzles 5 Putting the INK into INKjet 8 Designs on Inkjet Paper 11 The question is?... 12 Inkjet’ s differ ent images 14 Cut to Size 14 The Lar ger Chunk 16 Colour in Pr ofile 17 Jetting T rends 18 I NKJET PRINTING IS A NON - IMP ACT DOT MA TRIX PRINTING TECHNOLOG Y IN WHICH SMALL DROPLETS OR P[...]

3 Inkjet T echnol ogy Overvie w In the earl y days of inkjet print technology devel opment, poor col our image quality due to ink spreading and inter-col our bleeding (that is wher e the penetration of ink into the paper is too slo w to absorb multiple ink dr ops on the same spot in short intervals) were widel y re c ognized as the critical issues.[...]

4 Continuous inkjet Continuous inkjet – perhaps most widel y used in the industrial c oding, marking and labelling markets - can be designed using a binary or multiple defl ection system. Put simpl y, with a binary deflection system some of the ink-dr ops are char ged and some are unchar ged. It is the char ged drops that fl y directl y onto the [...]

5 Heads, Modes and Nozzl es N OT SO WITH PIEZO INKJET TECHNOLOG Y , WHERE THE ELECTRIC ALL Y CHARGED PIEZOELECTRIC CRYST AL PRESSURISES THE FIRING CHAMBER IN THE PRINT HEAD AND PUSHES THE INK OUT . E VEN THOUGH AN ELECTRIC PULSE IS UTILISED , IT ESSENTIALL Y TRIGGERS A MECHANICAL ‘ JETTING ’ PROCESS , SO VAPOUR BUBBLES DO NO T HAVE T O BE GENER[...]

6 Print head c onfigurations Inkjet technology is used in many diff erent ar chitectures and with differ ent operating principles, depending on the c onfigur ation of its print heads. With thermal inkjet technology, f or example, the print head can be a r oof shooter, with an orifice l ocated on top of the heater, or a side-shooter, wher e the orif[...]

7 All of these designs and their dr op performances ultimatel y determine the quality and throughput of a printed image. The tr end in the industry is in jetting smaller dr oplets f or image quality, generating faster dr op frequency thr ough a higher number of nozzles for additional print speed, while ine vitably trying to keep the co st of manufa[...]

Putting the Ink into Inkjet A RGUABL Y ONE OF THE MOST CRITICAL COMPONENTS OF INKJET PRINTING IS THE INK USED . I NK CHEMISTRY AND FORMULA TIONS CAN NOT ONL Y DICT A TE ( IN P ART A T LEAST ) THE FINAL QUALITY OF THE PRINTED IMAGE - E . G . THE BRILLIANCE OF COLOUR , THE IMAGE ’ S LIGHTF ASTNESS , ETC - BUT AN INK ’ S VISCOSITY AND OTHER PROPER[...]

9 Pigmented/Dye-based Inks Another major r ecent devel opment in the inkjet printing industry is the suc cessful impl ementation and c ommer cialisation of pigmented inks in col our printing applications. Many companies including r ecognised col our quality leaders like 3M, Dupont and Kodak alr eady have pigmented inkjet ink pr oducts on the market[...]

10 Sol vent/Oil-based Inks Sol vent-based inks are c ommonly used in indus trial marking or coating applications wher e the printing is done on a nonpor ous substrate such as plastic, metal, or glass. Because no absorption or penetration occur s, the printed image r elies on quick evaporation of the ink sol vent to be fixed onto the substr ate. How[...]

Designs on Inkjet P aper • Optimum print col our density (good fixation); • Fa st drying time without paper curl or cockle (f ast absorption); • High brightness; • Lightfast and waterf ast qualities; • W et rub and scuff resistanc e (no ink smearing); • Lateral ink spr ead to enhance text r esolution and col our-to-colour bl eed by cont[...]

12 After a while the image l ooks like it has a metallic sheen in dark ar eas ‘Br onzing’ occurs when dye-to-dye inter actions compete with the dye to substr ate interactions. The dyes in the ink aggr egate or crystallise on the paper surface, which l eads to a l oss in optical density . It can be limited by r educing the amount of black in the[...]

13 The shadow ar eas look grainy but the r est of the print it OK The effect, often r eferr ed to as ‘coalesc ence’, r efers to the way in which the ink is absorbed into the media. Sever al things can be done to counter it, the most important is to choose the corr ect print mode in the printer driver . In general terms the highest quality setti[...]

14 Inkjet’ s diff er ent images In newl y emerging ar eas like medical imaging and 3-D printing, significant impr ovement still needs to be made to the print head design and ink f ormulations in or der to fulfil the high e xpectations of printer r eliability and image durability demanded. But dr op-on-demand inkjet’ s capacity to print vivid co[...]

15 SOHO Paper Demands Cut size stock f or SOHO printing envir onments can be split into four main types: - Glossy c oated paper is ideal for photo- r ealistic imaging, but often considerabl y mor e expensive due to the PE coating, the binding systems, the differ ent pigments, namel y special pigments which allo w high transparenc e and high absorpt[...]

16 The Lar ger Chunk The intr oduction of wider print heads and multiple arrays c oupled with the availability of incr easingly high performanc e inks - UV curing, water-resistant, pigmented inks (see Putting the Ink into Inkjet, pages 8-10) - have br ought about a rev olution in the large f ormat application capabilities of inkjet. And, as a c ons[...]

17 This variabl e is known as metemerism and essentially points to the fact that an optimum digital inkjet c olour pr oof system must deliver 4,000-6,000 col ours in a gamut to match offset printing. A seemingl y short order if you consider that the human e ye can distinguish up to ten million col ours in its gamut. But still a significantl y tall [...]

18 Jetting T r ends In spite of multiple adv ances in inkjet printing technology ove r the last decade, all the indications ar e that the technology is set to gr ow even mor e over the c oming decade. The advent of the Internet, far fr om r educing the desir e for printed information as initiall y expected, has actuall y seen it grow, cr eating a s[...]

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Produc ed for M-real Digital imaging by The Bespoke Agency 2002. Printed on sil ver digital matt 200/150 g/m 2 on an hp indigo pr ess 3000 M-r eal Digital imaging AN DER GOHRSMÜHLE 51465 BERGISCH GLADBACH DEUTSCHLAND/GERMANY TEL.: +49(0)2202 - 152052 F AX: +49(0)2202 - 152805 M-r eal Digital imaging would like to thank all the companies that contr[...]