Overprinting

If the layout or illustration has two different colours superimposed, there are two possibilities: The foreground colour chokes the background colour, or it "overprints". Overprinting means that all separation colours not used in the foreground colours are transparent, and the background shines through in these areas. 

For example, a red defined as overprint (composed of yellow and magenta) is transparent in the colour separations cyan and black. The cyan or black contents of the background colour are then printed, so that the result is a mixture of background and foreground colour. 

Colours incorrectly defined as overprint (and not choke) are a common error in documents, because the resulting mixtures of foreground and background colours are often not displayed on the monitor and also not visible on many colour printers and proof devices. The result may be an unpleasant surprise.

                   the area left blank                                overprinting 

In general, we do not check overprint settings, because they could represent a design idea. Should the appearance of the printed product be changed due to such a "misadjustment", we will not accept liability. 

Summary:

  • Check your PDF file for unwanted overprint settings.
  • Black text will automatically be set to overprint.