Last week, HP announced two new Latex printers, fleshing out the company’s portfolio of Latex printers. For the past couple of years, a lot of the wide-format—and especially soft signage—conversation has centered around dye-sublimation (mea culpa), and latex printing technology has faded a bit from the public consciousness, even though at last month’s ISA Sign Expo, HP’s entire presence was Latex-based.

Here, then, I thought it was a good opportunity to catch everyone up on where latex (and Latex) is today.

Capital Equipment?

First of all, is it big-L Latex or small-l latex? We normally associate latex printers and inks with HP, which has by far the broadest portfolio of latex equipment, but Mimaki and Ricoh also offer wide-format printers based on latex ink technology, albeit a different one.

In case you are new to the topic, “latex” is a generic chemical term that, says Wikipedia, refers to a “stable dispersion (emulsion) of polymer microparticles in an aqueous medium.” Basically, plastic-like particles of pigment suspended in a water-based solution. Most folks are likely aware of this, but it never hurts to repeat that latex in this context is not related to the natural latex exuded by plants or the synthetic latex used to make gloves or other rubber-like items, so these inks are perfectly safe for people with latex allergies.

Latex inks are water-based, and don’t give off much in the way of harmful vapors (like solvent inks), nor do they require ultraviolet light exposure to dry (like UV inks), but they do require exposure to high temperatures to dry. The water-based nature of the inks has led some to claim that they are more environmentally friendly than other inksets, and this is true when compared to solvent inks. However, the extreme heat needed to cure them may, from an energy consumption standpoint, offset any environmental benefit. Still, advances in the ink technology, and the addition of an optimizing fluid, have helped lower the temperature at which the inks cure, improving the equipment’s energy footprint.

One oft-cited benefit of latex is that the inks cure very quickly—prints come out of the printer dry—which means they can be finished without having to wait for drying or outgassing.

Substrates

Another advantage of latex printing is its versatility, as it can print on a wide variety of coated and uncoated materials, from papers and vinyls, to backlit films, to textiles. Top applications for latex printing are banners, soft signage, vehicle graphics, and other indoor and outdoor applications. HP in particular has been seeing substantial growth in interior décor, from wallpaper and other printed wall coverings, to window treatments, to flooring, to upholstery.

New generations of at least HP’s Latex inks have imparted greater scratch and abrasion resistance, although when using them for things like vehicle or fleet graphics—which can get quite a bruising even under optimal driving conditions—an overlaminate or other kind of protection is advised.

Like other kinds of inks that use pigments rather than dyes, latex inks are highly UV-resistant, although (like other kinds of resistance) it will be a function of the substrate and the environment in which the print is placed. A banner installed outside in the direct sunlight of, say, Phoenix, Ariz., will have a different life expectancy than a poster installed in the dark, tomb-like confines of my office. HP offers a fairly comprehensive print durability guide, which should give you a sense of how latex will perform for the type of application you are looking to produce.

The White Stuff

If there is one limitation to some varieties of latex, it is a white ink option. White ink in general is problematic; to be useful, white ink has to be opaque, and that means bigger and heavier pigment particles, specifically titanium dioxide (TiO2), which can at worst clog printheads, and at best settle to the bottom of the ink reservoir, and thus need regular agitation to keep the pigment in suspension. HP’s Latex printers thus don’t offer white ink, and in fact the company has not found a great demand for it in the applications that are driving growth in Latex. The Mimaki and Roland latex units do offer white ink, as they use different printheads and ink formulation.

States of the Art

The two new “portfolio extender” series that HP announced last week are the 500 series (comprising the 64-inch Latex 560 and 570 printers) and the 126-inch (or 3.2-meter, depending on your metrics, as it were) Latex 1500. These two series fill in the large gap between the entry-level and mid-range 54- and 64-inch 300 series units (the 310, 330, 360, and 370) and the industrial-scale 3100 and 3500. The 500 series Latexes (Latices?) are designed for mid-size to large PSPs who need additional and faster units to keep up with increasing volume, and the emphasis is on speed and unattended printing. The 1500 is designed to be an affordable entry into superwide industrial Latex printing. Both these new series will be available this summer, and will be shown at drupa.

The HP Latex units print CMYK plus light magenta and light cyan—in various combinations depending on model—as well as a Latex Optimizer.

As I mentioned, both Mimaki and Ricoh offer latex units. Mimaki’s JV400-130LX and -160LX (54- and 64-inch, respectively) and Ricoh’s Pro L4130 and L4160 (54- and 64-inch, respectively), are available with CMYK plus orange, green, and white aqueous latex inks. (The Mimakis use the same Ricoh piezo printheads as the Ricohs, hence the similarities; HP uses its own thermal printheads.) The Mimaki/Ricoh ink formulation is different than HP’s (patents, you know), but still is chemically considered a “latex.”

Latex Lives!

Latex printing is one of the newest of the ink technologies, appearing on the market less than a decade ago, and many of its early limitations (poor scratch-resistance, very-high-temperature drying) have been overcome. And now there are more and more latex-based options, depending on your print volume and the kinds of applications you want to produce. Textile printing is all the rage today, and while latex is not suitable for garments and apparel (it won’t withstand repeated washing or other kinds of serious manhandling), it is well-suited for soft signage and other non-permanent textile applications. For these applications, it has advantages over dye-sublimation in that you don’t need to deal with transfer paper and heat presses, and latex can print on fabrics other than polyesters. It also gives you the versatility to print on vinyls and other non-textile substrates. It also dries very fast, so turnaround time can be expedited.

Latex isn’t suitable for everything, but many shops have found it to be a great solution for its versatility, its quality, and its ease of use.