If you’ve worked in the print design business for any amount of time, you’ve no doubt heard the term “rich black” more than once. If you’re not quite sure when or why to use it, read on for a brief explanation.
Because large areas of black ink tend to appear a muddy brown or charcoal gray color lacking richness and depth, printers recommend using a rich black (a mix of cyan, magenta, yellow, and black ink percentages) in large solid areas where black ink is desired.
When to use rich black:
There are no “set-in-stone” rules as to when to use rich black, but the following are times when I’ve found it best to do so.
- Solid areas – Rich black is best used in large areas where you want a nice solid black color. For instance, a pocket folder or brochure cover where you want a solid black background.
- Large type – If your type is a thick sans-serif type (such as Futura Black) and 40 points or larger, consider using a rich black.
- Overprint areas – If you have a light-colored background and want a large black area to print on top, use a rich black. For example, you have a textured yellow background and want a black circle with a logo in it to appear on top. If you use a regular black (100% black only), most apps like InDesign and Quark will overprint the black ink. When you print black on top of yellow, you end up with brown. The underlying color or image will show through. By using a rich black, you avoid the problem.
When not to use rich black:
While there are no rules as to when you should use rich black, there are a few rules on when you should NOT use it.
- Small areas – Small black areas on white or dark backgrounds. Trying to register a rich black on a 4 point thick line is virtually impossible – especially when it’s on a very light or dark background. The slightest offset in registration on the press will stand-out like a sore thumb.
- Small type – Registering multiple colors of ink on your 10 point type is bound to end-up looking poorly. Even the best of printers will have a difficult time.
- Newsprint – Though you can use rich black in newspaper ads, I discourage the use whenever possible. Putting that much ink in one area generally yields ink bleed and paper wrinkling.
Creating rich black:
Most designers eventually find a rich black that works best for them. For me, a 50% cyan, 50% magenta, 25% yellow, 100% black mix works great in most cases. But how did I come up with those percentages? Obviously 100% black is a standard. The remaining three colors are usually where the fluctuation occurs. I’ve found that having an equal amount of cyan and magenta, with yellow being about half those amounts, works best. I use less yellow because the yellow pigment in the ink tends to really muddy your black quickly. Why not use 100% of all four colors? You must take ink levels into consideration. Ink levels are the amount of ink your printer is putting down on the paper. Using too much ink will muddy the image, wrinkle the paper, and requires more time for the ink to dry properly; possibly causing you to miss a deadline. Using rich black is a trial and error type of thing. You can save yourself a lot of time by simply asking your printer what settings they get the best results with. Many printers have nailed down exact CMYK ink amounts for the best results on their particular printing press. If you’re using Adobe InDesign and Illustrator, be sure to visit the application preferences. You’ll find a section that allows you to display the color black accurately. Be sure to turn that feature on; it will save you plenty of grief later on.