DOSING AND PROCESS GUIDE

Masterbatch Dosage Rate and Calculation Guide

Masterbatch dosage is not a universal fixed percentage; pigment strength, resin, wall thickness, process, and target shade must be verified together in a representative trial.

Color Masterbatch Technical Team · 2026-08-12 · 4 min

What Determines Masterbatch Dosage?

The same color code may require a different dosage in another polymer, wall thickness, or machine. A supplier recommendation is therefore a starting point; the final rate is confirmed with the real resin and production process.

Color strength and opacity

Dark, opaque, or highly saturated shades make pigment loading and dispersion particularly important. Thin film and thick injection parts may need different addition rates to reach the same visual target.

Resin and machine conditions

Recycled content, natural resin color, moisture, feeding equipment, screw geometry, and temperature profile can all change the result. Dosage decisions must consider these variables, not only kilograms.

How Is Dosage Calculated?

For a simple starting estimate, multiply the base resin weight by the target percentage. Always confirm whether the percentage is defined against base resin weight or total blend weight, because the two conventions give different results.

Practical calculation

For 25 kg of base resin at a 2% starting dosage, the simple calculation is 25 × 0.02 = 0.50 kg of masterbatch. Confirm the value in a small trial and record the approved recipe before serial production.

Feeding and mixing accuracy

Calibration of volumetric or gravimetric feeders, granule flow, and mixing time are as important as the calculation. Unstable feeding can produce shade variation even when the nominal percentage is correct.

How to Recognize Low or High Dosage

A dosage problem should not be judged only by a lighter or darker shade. Surface, dispersion, cost, mechanical behavior, and process stability should be reviewed together before the root cause is confirmed.

Low-dose symptoms

Weak color, visible base resin tone, or shade fluctuation may indicate insufficient dosage. Poor mixing, moisture, or temperature drift can create similar symptoms, so each variable must be checked.

High-dose effects

Excess addition can increase cost and may affect surface or mechanical behavior in some applications. The safer method is to adjust in controlled steps and record color measurements and process notes for every trial.

Share your production quantity and target shade so we can define a starting dosage and sampling plan.

Related guides

Sources

What Is? · Contact

Correct calculation; consistent feeding too?

Coperion emphasises accurate material feeding for consistent results.

Technical source: Coperion · Masterbatch

Separate arithmetic from product recommendations

The tool below calculates mass only. It does not recommend a product dosage. Record target mass, actual mass and the calculation basis separately during trials.

General technical explanation, not a Color Masterbatch technical datasheet, test result or conformity certificate.

Calculate masterbatch quantity

Choose whether the calculation uses a percentage of the final blend or kilograms added to the base material.

This tool calculates mass only. The displayed values 100 kg and 2 are calculation examples, not dosage recommendations. Confirm the suitable dosage using product technical information and a trial on your production line.

How the calculation works

Masterbatch = final blend × percentage / 100. Base material = final blend − masterbatch.

Final blend = base material + masterbatch. Blend percentage = masterbatch / final blend × 100.

Example: 2% of a 100 kg final blend = 2 kg masterbatch + 98 kg base material. Adding 2 kg to 100 kg of base material gives 102 kg total and approximately 1.9608%.

Keep a record of your own trial

Download a blank worksheet. It is not a test result or compliance document; complete it for your own sample and process.

Blank trial record (CSV)Printable checklist