Traps and Underprints for Screenprinting


There are several ways for screenprint jobs to be misprinted, but there are also different things you can do to compensate for that when building your web-to-print artwork.

The process of printing directly from web graphics can be improved with some adjustments to the color separations.

When screenprinting bright colors on dark materials, an underprint color (usually white) is laid down first. If the bright color and underprint aren’t lined up correctly, the bright color will be dulled by the dark background — and the underprint may peek out.

To compensate, you can choke the underprint back — i.e., make it smaller in all dimensions, usually by about 1 point (1/72-inch, or 1/3 mm).

If the design allows for it, you may also trap the colored areas with a dark ink …often black. These trap colors don’t require an underprint — and if they are spread (made slightly larger), they can cover up a lot of misalignment errors.

See also: