Wide format printers from Monotech Systems

Manoj Kumar Garg, manager, wide format graphics, Monotech Systems, explains the technology and range of wide-format printers offered by the company

18 Nov 2015 | By Amardeep Singh

The technologies used in wide-format printers are based on the piezo electric drop on demand and then it is divided on the basis of the ink used in printers, like solvent, eco-solvent, UV and textile.

Types of printers
Printers are based on the type of ink they run on. They are primarily classified in the following categories:

Wide-format aqueous inkjet systems provide the fastest output with typically highest resolution. Aqueous inkjet printers can print on both indoor and outdoor materials, and with lamination, the outdoor longevity can be substantially increased.

Ideal for outdoor graphics production houses, one advantage of solvent-based inks is that they are less expensive than aqueous inkjet inks. You can use less expensive media when printing with solvent-based inks, and therefore, the signage industry has really taken to them.

The other emerging category in wide format inkjet technology is the UV-curable flatbed inkjet printer, where the drying mechanism for the ink is completely different than the mechanism used in solvent inkjet printing. When ultra-violet light hits curable liquid ink, it transforms it from liquid to solid on the chosen substrate. UV-curable printers offer many of the same features solvent inkjet printers offer, but with less expensive inks than aqueous inkjet inks and outdoor image durability without lamination. Since many are configured as flatbed systems, users can print directly on materials such as wood, metal, ceramic, glass, etc.

Textile printers are of two types. One is dye sublimation printer and the other is direct printer. In dye sublimation, sublimation ink is used and whereas in direct printer, reactive ink is used.

Media, print heads, printing inks and software
The following are the details of media, print heads, printing inks and software used in Monotech wide format printers:   

Printing inks
Solvent inks comprise a type of chemical called volatile organic compounds (VOCs), which evaporate readily. This means the ink dries fairly quickly. Solvent inks are pigment rather than dye-based, which makes them long-lasting and fade-resistant, are inexpensive, and are waterproof and UV-resistant. However, solvent ink vapors can be toxic, making them a workplace hazard requiring special ventilation systems. Disposal of used solvent becomes an environmental concern.

Eco-solvent inks were developed, which comprise a ‘milder’ type of solvent that take longer to evaporate, and often require heat, but are less hazardous.

Latex inks are water-based, which makes them a bit more environmental-friendly than solvent inks. What has driven the market for latex inks and their corresponding devices has been their ability to print on a wide variety of coated and uncoated substrates for both indoor and outdoor use on the same machine. They also dry quickly, which speeds the workflow, as finishing can be applied immediately after printing.

UV inks have become very popular in wide format printing. UV inks comprise chemicals that, when exposed to ultraviolet light, dry more or less instantly. UV inks dry fast, but can also produce more vibrant colors, can be used on a greater variety of substrates (such as plastics, vinyl, foil, paperboard, and other specialty substrates), and offer increased health and safety for press operators and the environment.

Wide format substrates can be either roll-fed or sheetfed. Roll-fed substrates comprise paper, flexible plastic, vinyl, canvas, and textile. Rigid substrates can include, but are no means limited to thick plastic, board, glass, wood , metal, three-dimensional surfaces like balls, laptop, computers, doors.

The company uses software like Photoprint, Onex, Ripmaster, Egrosoft, etc. Most print providers are familiar with the RIP — the raster image processor. RIP takes a file prepared for print (PDF, InDesign, Quark, PostScript, etc.) and convert all the text and graphics into dots that will then be generated by the actual printing device.

Some features and issues RIPs pay attention to are colour management, waste reduction, cost estimation and tracking, maximising processing speed, multiple device management, scalability and more.

Print heads
As part of the overall design and construction of the print head and its nozzles, the picolitre size is only one element to achieving a successful printed result. The larger the droplet size, the lower the end resolution but, in wide-format applications, there are the benefits that include the necessity for fewer passes and the fact that overall ink coverage will tend to conceal any blemishes. Smaller droplet sizes need a greater number of passes so that full coverage can be accomplished and, for many wide format jobs, this is really overkill, as the chances are the application is going to be viewed from a distance.

Monotech, for its solvent-based printers, uses print heads of Xaar photon, Konica Minolta, Spectra, etc. For eco-solvent printers, the company uses print heads from Epson and for UV-based printers the company uses print heads from Konica Minolta and Ricoh.

Among Indian players, Monotech considers Colorjet, Caldron and Negi as their competitors, especially in solvent-based printers.

Market trends
Due to the possibility of printing on almost all kind of media (ACP sheet, glass, wood, MDF, acrylic, tiles, etc) on UV-based printers (roll-to-roll and flatbed), the demand for this type of printers is on the rise. The market is shifting towards UV-based printers because almost all types of media are possible to print here.

Applications of wide-format printers includes signs, posters, banners, point of sale/point of purchase, backlit films, window displays, decor (wall coverings, floors, etc), vehicle wraps and textiles/clothing and more.

Ceramic tile printing
Screen printing was originally the main process used for ceramic tile printing. The process is notable for its ability to print high viscosity, large pigment particle inks, but it's a long-run process where every image has to be the same and changeovers take time. Inkjets originally struggled with high viscosities and large particle sizes of ceramic inks, but this has changed with new print head types.

Xaar in particular has developed heads for OEM printer makers that are well suited to the characteristics of ceramic inks. Xaar’s 1001 print head, introduced in 2007, was the first to successfully allow jetting of high viscosity large pigment inks for ceramics.

Ceramic inks are very different to conventional graphics inks. For one thing their pigments change colour, sometimes radically, during firing, which makes colour management a challenge. They use more viscous fluid than are used in signage inkjets, while the pigment particles are larger and more abrasive. Soluble salts and glues might also be printed for some effects.

Monotech’s plans for future
The company is looking forward to step into textile printing with Ricoh printing heads.

Monotech installations so far
In solvent and eco-solvent categories, the company has 450 plus installations and in UV segment the tally has 25 installations.