Why Card Colour Is Harder Than Paper

Card substrates are not paper. PVC, PET-G and PC have different white point, gloss and ink absorption, so the same CMYK values print a different colour than on a brochure. Add a protective overlay that shifts hue after lamination and a metallic or translucent card body, and colour can drift between the proof and the finished card even when the file is identical. Colour management exists to close that gap.

ICC Profiles: Mapping Intent to Substrate

An ICC profile describes how a device reproduces colour on a specific substrate. A card printer needs a profile built for its ink set and the exact card material, not a generic paper profile. With the right profile, the same design prints the same colour on two different presses, which is what lets a brand approve a master and trust every reorder.

• Build the profile on the real card stock, not a surrogate substrate.
• Re-profile when ink, overlay or press change - they all shift colour.
• Use the profile in the design workflow, not just at the RIP.

Spot Colours vs Process Colour

Brand-critical colours are usually specified as spot colours (for example a Pantone reference) rather than built from CMYK, because process mixing varies with dot gain and calibration. For cards, a spot ink or a dedicated station gives a repeatable match that process colour alone cannot guarantee, especially on glossy surfaces where dot gain is unpredictable.

• Use spot ink for logo and brand colours that must be exact every run.
• Reserve process CMYK for photographs and gradients.
• Agree a tolerance with the brand - aim for a delta-E, not a guess.

Proofing: From Screen to Physical Card

A proof is the contract between designer and printer. A calibrated soft proof predicts colour on screen; a physical card proof confirms it on the real substrate after lamination. Both must be viewed under a controlled light booth, because the same card looks different under office fluorescent, daylight and retail LED. Without a booth, 'looks right' is not evidence.

Card printing station where ICC profiling and spot colours hold brand colour across the run.

Measuring, Not Guessing: Densitometry and Spectro

Colour drift is gradual, so it must be measured on a schedule. A densitometer tracks ink density; a spectrophotometer reads the actual colour and reports delta-E against the approved standard. Logging these per shift turns 'the colour looks off' into a numeric trend that is corrected before a whole batch is rejected.

• Measure density and delta-E per shift, not only at setup.
• Log by press position; drift often starts at one edge.
• Set a delta-E reject limit with the brand up front.

Selection Quick Reference

Card colour management is measurement plus discipline: profile the real substrate, reserve spot ink for brand colour, proof under a controlled booth, and log delta-E per shift. Producers who do this ship cards whose colour the brand recognises on the first card of every run, not the fifth reject.