For professional printing, global colours can be made to overprint. By applying an overprint colour to objects selectively you can control overprinting.
About overprinting
Overprinting means that you can print one ink colour on top of another instead of, by default, the underlying colour being 'knocked out' (removed).
As a professional printing feature, overprint works when publishing PDFs using a CMYK colour space and PDF/X compatibility.
You don't need to explicitly make an overprint for black, for black text or black graphics, as this is set by default. On PDF publishing, you can control black overprinting using the Overprint black option in the Export Options panel (for any PDF export options).
An overprint colour swatch is indicated by a curved tab in the top-right corner of its colour swatch.
You can check if an overprint colour has been assigned to an object's stroke or fill by using the Colour panel.
In advance of using this feature, consult your print provider for advice on its use.
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- On the Swatches panel, -click the global colour swatch's thumbnail, then select Overprint.
SEE ALSO:
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