Paper basics X2

Apr 1, 2007 12:00 PM, By Constance J. Sidles

All papers have a color — even white papers. The color of paper affects the way inks appear on the surface, especially if you use process inks (cyan, magenta, yellow and black). That's because process inks are transparent. Light passes through the ink film, hits the paper and bounces back to our eyes. The colors we end up seeing depend on which colors of the spectrum are absorbed by the inks, and how much pure light is bounced back by the paper.

All papers absorb some wavelengths of light, thus preventing our eyes from seeing them. The whiter the paper, the closer it is to neutral, so the more pure light is reflected back. Colors on very white paper look brighter and purer than colors do when printed on white paper that has a color cast. For example, some white papers have a creamy color cast. They will make all inks look warmer. Other white papers have a blue cast. They will make all inks look colder.

Skin tones and the great indoors

If your designs demand great color fidelity, you should buy the whitest paper you can afford. This is especially true if you're printing outdoor photos, or if you're printing catalogs with items whose color must be perfect. On the other hand, if you're printing a lot of skin tones, you might want a white paper with a slight yellow cast. The paper color adds warmth to skin tones. Similarly, if you're printing indoor rooms, you might want the cozier feel of a warmer white paper.

If you want to use a colored paper stock, it might be difficult to predict exactly how your designs will be affected by the paper's color. Sometimes, a paper's color can totally change an ink color. For example, I once produced a brochure for the University of Washington, whose schools colors are gold and purple. My designer chose a golden-colored paper and designed a big, purple W for the front. Unfortunately, neither of us realized that purple ink on goldenrod paper comes out brown. None of our readers could figure out why we had produced a new logo color for the university. Was there some hidden message there about purple, or about the school's traditions? Nope — no message other than ignorance.

The best way to avoid this kind of problem is to ask your printer for a drawdown of the ink you have selected. A drawdown is a swash of ink slapped onto a sample of the paper you have selected. It will tell you exactly how your ink will look on your paper.

Finish: surface characteristics

Finish refers to the surface characteristics of paper. A finish might be smooth or rough to varying degrees. Coated papers are always smoother than uncoated papers, because the interstices between the paper fibers are filled in with a coating material. This makes the surface more uniform. Uncoated papers might be smoothed over a highly polished roller (these are called calendered papers), but the smoothing does not get rid of all the interstices. The surface is rough, even if it feels smooth. Uncalendered papers are even rougher; some have a texture that is actually pocked or ribbed.

Keep in mind that when paper reflects light back to our eyes, it doesn't do so perfectly. Paper scatters some of the light in random directions. Any light that is scattered away from our eyes detracts from the color intensity of the inks and the detail of the image, because the light that misses our eyes carries this information away; we never see it.

Making the grade

If your designs demand high color saturation and great detail, you should select the smoothest paper you can afford. A good measure of smoothness for white papers is “grade.” Grade is a technical term that refers to the amount of blue light a given paper reflects at a precise angle when tested in a lab. Grades number from one through five. The lower the grade number, the better the finish. A No. 1 sheet is the best quality; it reflects nearly all the blue light shined on it. It is the best choice for fashion designs, high-quality outdoor scenes and the like. It is expensive, however.

Sometimes, your designs might call for a rough, uncoated finish. For example, if you're reproducing art that simulates charcoal drawing or old-fashioned etching, you might deliberately choose a textured paper that scatters light wildly, thus making the designs look grayer and rougher.

The perfect paper is the one that best pairs your design needs with the sheet's characteristics.

Contact Sidles at csidles@isomedia.com.

News on paper

Eco-friendly papers

A vast amount of paper is consumed in the U.S. printing industry, and demand for recycled papers is on the rise. Early recycled paper grades faced criticism on myriad fronts. The paper mills have responded by advancing their technology to deliver high-quality recycled sheets. They are participating in environmental initiatives such as Forest Stewardship Council certification, while printers and publishers are making environmental commitments of their own.

For example, Scholastic Inc. (New York) has announced that all 12 million copies of the U.S. edition of “Harry Potter and the Deathly Hallows” will be printed on 30 percent post-consumer waste (pcw) paper. Sixty-five percent of the 16,700 tons of paper used in the U.S. first printing will be FSC certified. This marks the largest purchase of FSC-certified paper to be used in the printing of a single book title. And they're doing it all without magic.

Print: a moving target

Sappi Fine Paper North America has launched “Sappi Etc.,” a series of programs designed to help Sappi customers and industry professionals understand the changing dynamics of today's print production process.

See www.sappi.com.

Web forum

Domtar's (Montreal) online “Designer Corner” was created by designers, and it covers everything from industry news to designer profiles, eco-smart design options and tips for selecting the best paper.

“We are demonstrating our commitment to respond to customers' needs by developing innovative resources that enhance and facilitate their work,” says Tewfik Atia, marketing communications manager for Domtar EarthChoice papers. “Choosing the right paper is usually the first crucial step in creating an outstanding piece, which is why we've gathered tips from industry experts and provide designers with materials.”

See www.domtardesignercorner.com.