In the previous installment we detailed canvas printing using aqueous-ink printers. Here, we’ll discuss the pros and cons of latex, solvent and UV-curable printers for canvas…
Latex Layout
HP pioneered the use of latex inks in wide-format printing, and recently released its next generation of HP Latex 300-series printers. There are other latex printers out there, but HP’s Latex printers are the standard and best suited for canvas printing since you don’t need to coat the canvas after it’s been printed. Latex inks provide more durability and scratch resistance than aqueous inks and are touted as environmentally-friendly. For super-high production, the HP Latex 3000 provides all the benefits of latex printing, plus higher speeds at billboard-sized widths. Click here to find out what LexJet’s technical support director, Adam Hannig, found as he put the new HP Latex 360 through its paces.
Cost: The cost for the new 64-inch wide printer (the HP Latex 360) is priced around $20,000, which offers the most quality and flexibility within the HP 300 series. Ink and media costs are about the same as they are for aqueous and solvent printers since latex inks work with many of these media types.
Operation: It takes awhile for the heating element on older latex printers to get to the right temperature for printing, but this time has been cut down dramatically with the new HP Latex 300 Series. With latex, you can laminate right away since the ink is dry and outgassed once printed.
Durability: As mentioned with solvent printing, the additional durability of the latex inks allows you to skip the coating step for most applications, though the customer may like the look of a coated print and request it.
Quality: The HP Latex 300 Series also promises to boost quality, inching ever closer to aqueous-quality levels. The fact is that most wide-format inkjet printers will produce the quality you need for high-volume décor canvas printing. If you have a pickier clientele for more custom canvas work you should request samples from the manufacturer/distributor of the printer you’re interested in using files you supply them.
Maintenance: Latex requires less maintenance than a solvent or UV-curable printer, but more than an aqueous printer, though the HP Latex 300 Series includes new features like a maintenance cartridge, instead of a maintenance tank, making maintenance easier and faster.
Solvent Solutions
Solvent printing was a godsend to the sign industry when it first arrived on the scene. Commercial sign makers were continually carping about outdoor durability and the lack of it before solvent printers were introduced to the signmaking scene.
Printer manufacturers rushed to meet this demand and developed a solvent ink set designed to permeate and penetrate vinyl. Aqueous inks are anchored to the surface by an inkjet coating, so the ink sits on the surface, making it less permanent. One way to look at this relationship between ink and vinyl is that solvent ink is like a tattoo and aqueous ink is more like a sticker.
Most of those early solvent inks were hard solvents that were rather caustic and as such could bite into just about any material. Since then, the industry has moved to low/eco solvent inks, so the media designed for these inks requires some sort of treatment or coating to ensure ink adhesion.
As such, more high-volume fine art and décor reproduction companies are migrating to solvent since it eliminates the need for post-print coating; just pick the canvas finish – gloss, satin or matte – and go straight to stretching and finishing.
There is a great range of printer types, from entry-level units that are 54 in. to 72 in. wide and cost between $16,000 and $30,000 to giant 16-foot super-high production printers that can cost up to half a million bucks.
For the purposes of the following solvent printer discussion, we’ll use the Epson SureColor S70670 64-inch low-solvent printer as our benchmark as it sits in that entry- to mid-level range, provides near-aqueous quality printing, and is similar in cost and overall capabilities to those in the same range manufactured by Mimaki, Roland, and Mutoh…
Cost: As mentioned earlier, solvent printers have a higher average entry cost. For typical operation, ink and media costs are generally lower than they are with aqueous printers. But again, media represents only a small percentage of a print operation’s overall cost, so it’s not a significant factor.
Maintenance: The latest generation of solvent printers typically require only an hour or less of maintenance once a month.
Operation: Outside of minor maintenance, solvent printers will run continuously and similar to an aqueous printer. However, there’s usually a recommended drying and outgassing time recommended before lamination based on the printer model.
Durability: Solvent prints are extremely durable, opening up a wider range of applications that don’t require lamination or coating, including canvas.
Quality: Solvent printers, particularly Epson’s, have made great strides in quality. Though you’re not likely to find the same quality as you will with aqueous printers, there are certain models that come very close to aqueous quality. It’s also important to keep in mind that quality is not only a function of the printer, but of the color management workflow and the media being printed to.
Printheads: Most solvent printers use piezo printheads, which are more durable and long-lasting than the thermal printheads typically found on aqueous printers (excepting Epson’s aqueous photo printers, which also use piezo heads).
Curing Time
For some, UV-curable printing represents the Holy Grail of sign printing because it’s the only wide-format technology that allows direct printing to board materials, such as Coroplast, Gator Board, Sintra, and even doors and tabletops. UV-curable inks are cured or set using UV lamps that are built into the printer so the inks adhere to more materials.
And, with the advent of hybrid UV-curable printers – those that can switch from flatbed to roll-to-roll, such as the CET Color X-Press – the printing potential becomes almost limitless. But with this seemingly limitless capability is an attendant complexity.
Moreover, UV-curable inks are generally not designed for the canvas printing process. The inks are simply not flexible enough for the stretching process, but should be fine for mounted or framed canvas prints.
Applications: A UV-curable printer eliminates the painful application step for board applications; simply print and go. Almost everything, excepting vehicle graphics and stretched canvas, is fair game for a UV-curable printer, allowing more opportunities to make a difference with specialty graphics.
Durability: The durability of UV-curable rivals solvent, and rarely needs lamination, unless you’re looking for a different texture or more rigidity for roll materials.
Quality: For canvas printing, UV-curable printers are really a last resort. If the bulk of your work is direct-to-board printing and you have an occasional canvas project you could certainly do it, particularly if you aren’t planning to stretch and frame the canvas. Some shops print directly to a pre-stretched blank canvas, but in that case you have to paint the edges as most people expect either a gallery wrap (where the image continues onto the edges of the frame, usually mirrored) or a museum wrap (a solid color on the edges).
Cost: Low-end UV-curable printers start at around $60,000 and range up to half a million dollars for a high-quality production printer. The hybrid CET Color X-Press and others like it were designed to strike a balance between economy, production and quality as the lower-end machines are not as sturdy and reliable, while the higher-end industrial printers represent an extraordinary capital investment. You can also use less-expensive uncoated materials and UV-curable inks are generally less expensive.
Maintenance: UV-curable printers require more detailed and time-consuming maintenance about once a month.
Operation: Because of the relative complexity of UV-curable printing, and the need to adjust the printhead height based on the material running through the printer, the variables in the process increase proportionately. Plus, you may need an additional operator, at least part time. High-performance, high-volume printers burn through material quickly, and the material used is often quite heavy. Where a roll of 36 in. wide material is easily loaded on an aqueous or solvent printer by one person, a 300 ft. roll of 60 in. material can weigh around 100 lbs., so someone else will need to be available to help load heavy materials or big boards onto the printer.
For the rest of this series, click on the following links:
Part 1: Materials, Finishes and Textures
There are basic details that should not be overlooked as graphics are being prepared for application, and the preparation has to begin before the beginning. First, be sure to allow the ink to dry and set for a minimum of 24 hours. Then, it’s safe to apply to whatever substrate you’re using. Here, we’ll stick to flat, relatively smooth surfaces, like sign boards and barricades, rather than irregular ones with compound curves, or other surfaces like glass, carpets, and concrete.
