Inks are generally categorized by the color carrier – the ingredient that mixes with the dye and is delivered to the printing surface – or the way the ink is cured once it reaches the printing surface. Here are some of the more commonly used inks:
The most common kind of inks available today are aqueous inks, which use water as a carrier for the dyes or pigments that provide the color. They are generally used for printing directly on a flat surface such as paper, vinyl or canvas.
Aqueous inks are usually used in the desktop printers we’re all familiar with but may also be used in some large-format printers, depending on the job requirements. However, most large-format printers usually use a dye sublimation ink, which is also aqueous.
Aqueous inks usually produce extremely high-quality, rich results and are therefor the preference for photo and detailed prints. On the other hand, aqueous inks usually have a limited outdoor life and limited weather resistance.
Solvent inks come in different strengths, from mild to strong (depending on their purpose) and are generally used for products where durability is required. For that reason, solvent inks are considered the “workhorse” ink and used for exterior signs, banners, posters and vehicle wraps.
Solvent inks are not available for most desktop printers but are common in industrial printers.
The advantages of solvent inks, besides their durability, are their relatively low costs and their flexibility when dry. They do, however, require effective ventilation when in use, clog printheads easier that other inks and also take longer to dry that aqueous inks.
UV curable inks are thick and often resemble liquid plastic. Once the ink is applied to the printing surface, it cures (dries) immediately upon exposure to ultraviolet light.
UV inks are especially adaptive to uncoated and unusual materials such as wood, glass, or leather. Most other inks won’t work properly on such surfaces.
Although reserved for industrial use, printers that use UV ink come in all different sizes, for printing on something as small as a golf tee, or as big as a picture window.
Very quick drying times and low-odor levels make UV a popular choice for product printing. On the downside, they can be expensive when compared to other inks, can be tricky to use and only have a limited amount of flexibility once cured.
Latex inks, a fairly new ink technology, require heat in order to cure on most substrates. Very similar to solvent, the latex printer is becoming the workhorse of the sign industry and is almost always only used in large-format industrial printers.
Latex ink work on most surfaces, have fairly low ink costs and no volatile emissions. At this point, because the technology is still somewhat new, latex inks do not come in the variety of colors that other industrial inks (such as solvent inks) do. The heat required to cure latex inks may also be an issue for some printing surfaces. Nonetheless, the non-toxic nature of latex inks is causing them to gain popularity among commercial printers.
There are, of course, other kinds of specialty inks for very specific purposes. But the chances are that the signs, stickers, banners, and flags you see driving home tonight will have been printed with one of the inks listed above.