How Can I Print With Metallic Inks?

Answered by Stephen Beals, Digital Pre-Press manager and industry writer

Question:
We have a metallic ink as one of our corporate colors and we have issues with smearing. I know to allow extra time for drying, but can I use UV inks? And if so, what would it do to the color? Also, would I then need to add an aqueous over it?

JC

Answer:
There are so many variables concerning inks, drying methods (using chemical drying agents in the ink itself vs. "air drying" vs. heat or moving air mechanical drying and so on. You also don't mention what paper you are printing on, and that's also a factor.

But there are a few tips we can offer for dealing with metallic inks that might be helpful in general.

First, you are right to be concerned with how an aqueous coating might effect the color. The metallic flakes in inks (which are generally made by using metallic flakes embedded in what is essentially a clear varnish) rise to the surface as the ink dries, and much of the "sheen" you see can be lost if the particles don't rise to the surface. A coating could inhibit that process. The coating itself might tend to make the ink look "dull" by limiting the reflectivity of the particles. One answer to this is to mix some metallic ink with a varnish, but of course you can't do that with an overall coating.

But if durability is more important than sheen, varnish is certainly an option.

One other thing to note: some metallic inks do not play nicely with laser printers. The heat breaks down the ink.

It's generally best to print metallic's on coated stocks running a minimum of water on press to allow faster ink set-up. If smearing is the problem, the press operator might simply need to cut back on the water when printing the metallic ink. Another possible option is to "double hit" the metallic, running the initial hit lighter than the second one. The low volume of ink on the first hit keeps it from smearing, and the second hit gives you the full impact of the metallic look.

Pressmen also tell us metallics should be mixed at least 24 hours in advance because they go through some chemical changes over time and it takes a day or so to "settle out."

There's also a relatively new metallic ink called Mirasheen that has sharper, thinner flakes than regular metallic inks, which give it a brighter reflection. It's a UV ink suitable for offset, narrow web, flexo and screen processes. Wolstenholme has an online calculator, called Inkantation (www.wolstenholme-int.com/uk/ inkantation.php), to see if it's appropriate for your application.

Some printers specialize in printing metallic inks, and others almost never run them. Metallic ink needs special.

Stephen Beals is a digital pre-press manager and has been writing for major print publications for many years. He is the author of A Practical Primer for Painless Print Production. He can be reached at stephenbeals@mac.com.
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