You can specify that a colorant (usually only a spot color) be trapped like a black color. Keep in mind the following rules about ink types:

• Normal inks can be trapped as black if you select the Treat as Black option.
• Other colors trap to opaque inks, as opaque inks are always treated as black.
• A screened ink is only treated as black if you select the Treat as Black option, and its tint is greater than the Black Color Limit setting.
• Transparent or OpaqueIgnored inks are never treated as black.

See Also

Trapping black ink