Plastic additives as pellets, which are added to the natural raw polymer to dye or to change the properties, are called Masterbatch.
They have a higher amount of colorants or additives than the raw polymer.
It is to be noted, which substrate is used (mainly PE or PA).
Masterbatches are easy to handle and provide a better process reliability than powder additives.
There are additive masterbatches (e.g. flamability or UV-stabilization), color masterbatches (to dye) and combination masterbatches (dyes and additives).
A small percentage of the masterbatch is enough for an intensive dyeing.