Matching a Pantone colour in plastic: why it is never exact, and how to approve it
A Pantone number is a starting point, not a guarantee. What decides whether your production matches your expectation is how the colour gets approved.
Why 100% identical is not possible
Pantone references are printed ink on paper. Plastic is a different base with its own colour, and the finished shade is also moved slightly by melt temperature, pressure and cooling speed. Then the light you look at it under — office lighting or daylight — shifts it again.
What a factory can honestly promise is a colour that looks right to the eye and sits inside the industry colour-difference tolerance. Anyone promising an exact match on plastic is promising something they cannot measure.
The same Pantone looks different in PP and Tritan
PP is naturally milky and semi-matte. Tritan, a copolyester, is clear and bright. Put the same colourant in both and the clear material shows the colour deeper and more saturated, while PP makes it lighter and slightly greyer.
So a set of PP lids and a Tritan bottle 'in the same Pantone' will not look the same side by side. If they sit together on the shelf, approve them together, as a pair.
The tolerance we work to
We judge colour two ways, and a batch has to pass both:
- Measured: a colour difference of ΔE 3–4 or less against the approved standard, which is the common tolerance for moulded plastics. The lower the ΔE, the closer the colour.
- Visual: compared against the approved colour plaque in a light box under D65 (standard daylight) illumination.
Which finishes are hardest
From easiest to hardest: transparent tints, then frosted finishes, then pearl and fluorescent colours.
Pearl and fluorescent pigments react to small changes in temperature and mixing, so a minor drift in settings changes the colour. They have the highest rate of re-matching. If your range includes one, allow an extra round of colour approval.
Masterbatch minimums, and small orders
A dedicated colour masterbatch is usually made in minimum lots of 5–10 kg. On a large order that is nothing. On a small order in an unusual colour, most of that batch is never used, and the factory absorbs the cost.
That is why a small order in a special colour usually carries a colour-matching charge. If you are testing a market with a small first run, a colour close to one already in use avoids most of that cost — ask which colours are running.
The screen problem
We often receive a colour as a screenshot, or 'the blue on our website'. Phone and computer screens differ from each other, and brightness can be changed, so a screen cannot be a colour standard.
Our process is always the same:
- Give us a printed Pantone number from a physical colour guide.
- We mould and send a physical colour plaque.
- You sign the plaque, and that signed plaque — not a screen, not a file — is the standard for production.
It adds one step at the start. It removes the most common colour complaint at the end.