What Is Masterbatch? Coloring and Additive Methods

Masterbatch is a pellet-form intermediate product made by homogeneously dispersing a color pigment or a functional additive at high concentration (typically around 20-50%) in a carrier polymer. The processor mixes this concentrated pellet with natural (uncolored) PP/PE raw material at a specific ratio (typically around 1-5%) to reach the desired color/property intensity in the final product.

Pure pigment powder is a material that is difficult to dose precisely and homogeneously in very small quantities; incorrect/uneven distribution can lead to specks, streaks or color inconsistency in the final product. Masterbatch greatly reduces this risk by pre-melting and homogenizing the pigment in a carrier resin, reducing dosing for the processor to a simple, repeatable ratio.

The masterbatch's carrier resin must be compatible with the base raw material it will be added to — for example, a masterbatch to be added to PP pellets generally has a PP-based carrier. An incompatible carrier can cause irregularity in melt flow or mechanical weak points in the final part.

Masterbatch is used not only for coloring; functional additives such as UV stabilizers, antioxidants, flame retardants or antistatic agents can also be added to the raw material using the same method (concentrated carrier pellet) (see the 'Additives Guide' article).

The PP/PE grades in our catalog are natural (uncolored/natural-colored) raw material; the coloring process with masterbatch is carried out by the processor on their own production line. We recommend working with your supplier (the masterbatch manufacturer) on the right masterbatch ratio and compatibility.