Answer: Black created by a CMYK mix!
Unfortunately, Black ink in offset printing isn’t very Black. By nature, offset inks – CMYK – are not 100% opaque, thus you will never get the super dark, rich Black you see on your screen. To make up for the ink’s shortcomings, especially in large solid areas, many print providers ask you to pump up your 1-color Black for the offset printing process by adding some Cyan, Magenta and Yellow to your files. Also referred to as “rich Black,” this color combination usually revolves around 40% Cyan, 40% Magenta, 40% Yellow and 100% Black. Ask your printer for their preferred formula.
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