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Metallic inks: Unusual, eye-catching, simple.

Metallic inks share the visual properties of common metals such as gold, silver, copper or bronze—a shimmery depth and sparkle that catch and reflect the light, much like the metal itself. How does the ink achieve this? Read on.

Ink manufacturers start with a base pigment that matches the color of the desired metal. Then they add small metal particles, typically bronze, aluminum, copper or zinc, which create a glittery metallic effect when the particles migrate to the surface as the ink dries. This process is called leafing.

Experienced offset printers know metallic inks require some skill because they have a different ink-water balance than conventional inks. They also know the extra care pays off with enhanced visual impact—an opaque, reflective ink surface that catches the light, the eye and, hopefully, the fancy of the target audience.

Drying time and surface enhance the metallic effect

The leafing process benefits from longer drying times. Simply put, the longer the dry, the higher the shine. Which is why it’s not a great idea to use ultraviolet inks, because the fast UV-based drying process will dull the effect.

Surface matters, too. In general, a harder and less-porous surface will maximize the reflective, metallic effect. This makes premium gloss coated paper ideal for getting the desired results. If you run metallics on a dull or uncoated sheet, you’ll want to consider two hits of the ink to achieve smooth, consistent color saturation on the surface.

How to avoid ink rub-off

Metallic ink’s leafing process does have a downside: The metallic particles can rub off the printed piece onto surfaces it comes in contact with, such as a facing page or the rest of the run. This is easily solved with a protective coating such as a spot varnish or aqueous coating. To minimize softening of the metallic luster, it’s a good idea to consider dry-trapping (applying after the ink dries) the coating.

A variety of choices for a variety of effects

In addition to traditional metallic inks, there are other choices such as liquid metallics, which provide a higher level of shine, or pearlescent inks, which do a very good job of mimicking the multi-color sheen of pearls. Image reproduction—halftones, tri-tones, even mixing metallics with four-color process—offers even more ground for exploring different effects. Be careful, though, with reverses. Small or fine type or rules can have a tendency to fill in because of the relative coarseness of the metallic particles.

The bottom line: Metallic inks, creatively and skillfully applied, can be a real marketing value-add in conveying a rich, elegant, high-quality and memorable impression for your brand.