Color matching in plastics: why your shade does not match and how to fix it

The scenario repeats itself in many plants: the part comes off the machine and the shade is not the one the customer approved. The previous batch was correct, the formula is the same, and yet the color changed. There is almost always a measurable cause behind it.

The most common causes of shade variation

• Visual reference instead of a measurable one: approving color "by eye" under office lighting produces different shades under shelf lighting.
• Change of resin or resin supplier: the base yellowness of the polymer shifts the final shade.
• Process temperature out of range: some organic pigments degrade and shift above their thermal limit.
• Inconsistent dosing: variations in the feeder change the pigment concentration in the part.
• Pigment from a different source between batches of the concentrate.

What a color match against a reference is

Matching a color means formulating a concentrate that reproduces a specific reference: a physical sample, an approved part or a Pantone number. The laboratory measures the reference with a spectrophotometer, formulates with pigments compatible with your polymer and instrumentally compares the result against the target.

The trial on your machine is the real validation

The laboratory plaque confirms the formula. Your process confirms the product. Serious validation includes running the concentrate on your own machine, with your resin and your conditions, before the volume order. If your supplier skips that step, the risk stays on your side.

How to start a color match

• Send your reference: physical sample, approved part or Pantone number.
• Indicate polymer, process and working temperature.
• Point out whether the application touches food or requires any standard.
• Receive the formula proposal and the sample to validate in production.

At Delta Pigmentos, color matching is carried out as an authorized Pantone partner and with our own laboratory. Share your reference on WhatsApp and we will reply with a technical proposal and development lead time.