If you heard the phrase ‘designers never use the colour black in artwork’ you are wrong. And a solid shade of black isn’t as simple as it looks. To get the best results, black can be produced in two ways. The first method is Process black, and/or made from 100% black ink. This is ideal for small areas less than 30mm2 such as text or logos. Too much ink coverage in small areas can result in and/or sheets sticking together.
On areas of over 30mm2 in size, process black can appear washed out and uneven. This is because the rollers on lithographic printed presses roll the ink over a large area. The alternative is rich black, which consists of 100% black and 40% cyan. A rich black should be used on larger areas to ensure and even dark coverage, as the second ink disguises any inconsistencies. however, rich black should never be used on small text as any tiny deviance in registration will lead to a blurred effect. It is important to bear in mind that the higher the ink coverage, the longer the drying time required. This is particularly true of uncoated (non-glossy) stocks such as business stationary. Black will inevitably appear duller on uncoated stock because of the absorbency of the paper. This absorbency also means that any fine detail reversed out of black may disappear. We do not recommend less than 8pt text, for example, on uncoated stock. You may think it would be okay to have three or four colour black text. It is virtually impossible to print four colour black and will look blurred and may also cause sheets to stick together.
Also be aware that black within a photograph as a background may have a different CMYK compared to other parts of your design. This will be noticeable when printed, even if not on screen. Placing a photograph with a black background over a black area in Quark, for example, may reveal a difference between the two shades of black when printed. To overcome this, take a sample of the black that the background is required to match in an application such as Photoshop, using the colour picker tool. Then simply mix the matched colour paying careful attention to the overall ink coverage.
You’ll get best reproduction from colours that are made up of two inks for example magenta and cyan etc, with the exception of shades of black.