Ed #9 Understanding Ink

While ink and varnish typically account for about 10% or less of a project’s printing budget, they can have a big impact on the finished product. But getting the results you’re looking for can be challenging.

First, it’s important to make sure that everyone is looking at the same colors.

That’s where the Pantone Matching System (PMS) and other color matching systems, like the Toyo Ink System, come in. First developed in the 1960s, the Pantone Matching System provides a standard reference for selecting, specifying, matching and controlling ink colors.

Just as preschoolers mix yellow and blue finger paint to create green, the Pantone Matching System uses 14 basic colors to create more than 1,100 solid, or spot, colors. Each is printed on coated or uncoated papers, typically on gloss or matte finishes, along with the formula used to create the color. Printers can order the color by its number or mix it themselves according to the ink mixing formula found in a guide. Another guide compares the solid colors to the closest possible match in standard four-color process printing.

Even with the same swatch, however, you and your client may not see the same shade. Colors can change, or shift, dramatically when viewed under different lighting conditions. Other factors can affect color perception too. Fluorescent inks can fade quickly, so someone looking at an older swatch of the color will see a different shade than someone looking at a newer swatch of the same color. The same is true to a lesser degree for virtually all inks—in fact, Pantone recommends replacing color guides once a year.

It’s also important to remember that the color that’s printed on paper looks different than color on a computer screen. And to complicate matters further, the color shown on one monitor may not match that seen on another.

Printers and others have taken steps to control these variables. Monitors at different locations can be calibrated to produce virtually the same colors. And international color viewing standards, which call for printed color to be viewed in a light booth illuminated to 5,000° Kelvin, assure that everyone literally sees color in the same light.

Of course, there are other considerations as well. The type—and color—of the paper stock can also have major impact on the color. Coated and uncoated papers will yield somewhat different results, which is why each has its own swatchbook of colors.

To see exactly how color looks on the specific stock you’ve specified, you should ask the printer for an ink drawdown. The printer will mix your chosen inks and spread some on the specified stock, either by hand or by using a small press. You won’t be able to see how screens of the color will look, but you will get at least a general idea of the final appearance of the printed piece, which is especially important if you’re using a colored stock.

Inks—and color—are also affected by the shop environment. Heat can cause the tack of the ink to drop, which can cause dot gain. That’s why some people say it is better to print in the morning than in the afternoon. High humidity—and a number of other factors—can cause ghosting, when a faint, shadowy copy of an image appears on the opposite side of the stock on which it is printed.

The key to making ink do what you want it to is to work closely with your printer. Discuss the colors, stocks, and coatings you are considering—and ask about their experience with them. Make sure that all are compatible. Some ink pigments may show undesirable color shifts after an aqueous or UV coating is applied, for example.