Colours

Spot colours

  • Spot colours are printed using a single, pre-mixed standard ink selected from a numbered list provided by the ink vendor, rather than a combination of the four basic colours in CMYK (cyan, magenta, yellow, and key) printing. The most common vendors are the Pantone Matching System (PMS) in the U.S. and Toyo Ink in Europe.
  • Since the spot colour is premixed, it uses only one plate (vs. four plates for a CMYK mix of a similar colour) and does not change from page to page during the print run. This makes spot colour ink printing ideal for consistency, particularly on those important elements like logos.
  • Spot colours are typically used in offset printing and screen-printing, usually in large runs. If two or three spot colours are used for a print project, it is labeled as a 3 colour job. However, a specific plate has to be made for each spot colour so the costs for such a printing job can drastically increase.
  • A spot colour can be used in different shades and tints, see the glassCanopy logo which uses the PMS color 5483.
  • Spot colours have some advantages over process inks. They allow printing colours that are impossible to produce by mixing the process colours — for example, metallic and neon colours but also gold and silver, opaque white and certain greens and blues. They are indispensable to complement the colour spectrum that can be implemented with process inks, but they cannot completely substitute process colours.
  • There are two primary reasons why spot colour is used:
    1. To ensure consistency.
    2. Keep printing costs down. NOTE: only relevant if only using 1–3 colours. Each colour plate that is used during a print run costs money.
Spot colours fans
glassCanopy logo

How to decide on colour mode?

RGB for anything digital — web, screen — and not for print. Light based and with a much broader range of colours, RGB will always produce brighter, more vivid colours than CMYK.

CMYK or spot colours for print jobs. Nearly all print houses will request a job in CMYK unless the job has been requested in spot colours. However, some printers and print houses prefer having the job presented in RGB mode because these printers have the ability to print in a wider range of colours. This kind of printer will manage the colour output and can produce more vivid colours than a CMYK job. Have the print house advise on what works best for their printers.

When a project has only 1–3 colours, it makes sense to use spot colours — but continuous tone images like a photograph or artwork must be reproduced with 4-colour process inks.

UV varnish/ Coating

  • Name the layer Varnish. Don’t use a colour that’s already been used in the document.

Sources:

Course material; Mixam print service; Glass Canopy marketing agency, ASK design blog, Everything you need to know about spot colours