Masterbatch is a concentrated mixture of pigments or additives dispersed into a carrier resin, supplied as granules and metered into raw polymer during processing to colour or modify the finished plastic product.
Instead of handling loose pigment powder on the shop floor, a processor adds a small percentage of masterbatch granules – typically 1% to 5% – alongside the natural resin at the machine. The masterbatch melts and disperses, carrying its pigment or additive package evenly through the polymer.
That’s the whole idea. The value is in the words concentrated and dispersed.
Why masterbatch exists at all
Pigment on its own is a difficult material to use in a plastics plant.
Dry pigment powder is dusty, it contaminates equipment, it’s hard to dose accurately, and it does not disperse readily into a polymer melt. Agglomerates survive into the finished part as specks, streaks and colour variation, and in thin film they show up as gels or actual failures.
Masterbatch solves this by doing the difficult part – breaking down pigment agglomerates and distributing them evenly – once, under controlled conditions, in a compounding plant with twin-screw extruders and proper quality control. The processor then receives a clean, free-flowing granule that behaves like the resin it’s going into.
You are buying dispersion work, not just colour.
The three parts of a masterbatch
1. The pigment or additive. The functional payload – organic or inorganic pigment for colour, or an additive such as a UV stabiliser, anti-block, slip agent, antistatic or flame retardant.
2. The carrier resin. The polymer the payload is dispersed into. This is the part buyers most often overlook, and it matters enormously – see below.
3. Dispersing aids and additives. Waxes and dispersing agents that help wet out the pigment and carry it into the melt.
Why the carrier resin matters more than people think
The carrier is the polymer that transports your pigment into your product – and it stays in the finished part.
If the carrier is compatible with your base polymer, it melts and blends invisibly. If it isn’t, it forms a separate phase. The colour may look acceptable while the mechanical properties quietly degrade, because an incompatible carrier acts as a stress concentrator. Parts fail at loads they should survive, and the cause is almost never traced back to the masterbatch.
A PP-carrier masterbatch dropped into PA6 is the classic example. It’s cheap, it’s available, it colours the part, and it can compromise it.
This is why a serious supplier asks which polymer you’re running before quoting. “Universal” masterbatch exists and has its place for undemanding applications, but it is a compromise, not a default.
Types of masterbatch
| Type | What it does | Typical use |
| White | Opacity and whiteness, via titanium dioxide | Packaging film, caps, houseware |
| Black | Colour and UV protection, via carbon black | Pipe, geomembrane, cable, agricultural film |
| Colour | A specific matched shade | Almost any moulded or extruded product |
| Additive | Modifies behaviour, not colour – UV, anti-block, slip, antistatic, antifog | Film, outdoor parts, electronics packaging |
| Filler | Adds mineral filler, usually calcium carbonate, to reduce cost | Woven sacks, thick-wall moulding |
| Special effect | Metallic, pearl, shimmer, granite, marble | Cosmetics, houseware, premium packaging |
| Mono concentrate | A single pigment at high loading, for in-house matching | Processors doing their own colour work |
White, black and colour cover the overwhelming majority of volume. Additive masterbatch is where most of the engineering conversation happens.
How much masterbatch do you use?
The proportion of masterbatch added to natural resin is called the letdown ratio, expressed as a percentage or a ratio.
A 2% letdown means 2 kg of masterbatch per 98 kg of natural polymer, or 1:50.
Typical ranges:
- Colour masterbatch: 1-4%
- White masterbatch: 2-8%, depending heavily on wall thickness and opacity target
- Black masterbatch: 1-4%, but driven by whether the black is for appearance or UV protection
- Additive masterbatch: varies widely by additive and target performance
Two things change these numbers more than anything else:
Wall thickness. A thin film has almost no material to hide behind, so it needs far more pigment per kilo than a thick moulded part at the same visual opacity.
Pigment loading in the masterbatch itself. A masterbatch at 60% pigment loading is dosed at roughly half the rate of one at 30%. This is exactly why comparing suppliers on price per kilo of masterbatch is misleading – the meaningful comparison is cost per finished part, or per square metre of film.
Masterbatch vs compound vs dry pigment
Three formats exist for getting colour into plastic.
| Dry pigment | Masterbatch | Compound | |
| What you buy | Loose pigment powder | Concentrated granules | Fully coloured, ready-to-run resin |
| Dosing | At the machine, difficult | At the machine, simple | None – it’s already done |
| Dispersion quality | Depends on your equipment | Done for you | Done for you |
| Cost per kg of resin | Lowest | Middle | Highest |
| Changeover flexibility | High | High | Low |
| Housekeeping | Poor – dusty | Clean | Clean |
Most processors are best served by masterbatch. Dry pigment suits operations with strong in-house compounding capability and the equipment to disperse properly. Fully compounded resin suits high-volume, single-colour runs where changeover flexibility doesn’t matter and consistency is worth the premium.
We’ve written a longer breakdown of this decision: Masterbatch vs Compound vs Dry Pigment
How masterbatch is made
- Formulation. Pigment or additive package selected against the target colour or performance, and matched to the intended carrier and end polymer.
- Pre-mixing. Ingredients blended to a uniform pre-mix.
- Compounding. The mix is fed through an extruder – usually twin-screw for demanding grades – where shear breaks down pigment agglomerates and distributes them through the molten carrier. This step is where masterbatch quality is actually determined.
- Pelletising. The melt is cooled and cut into granules.
- Quality control. Colour measured against a retained standard; dispersion checked, often by filter pressure value testing for grades destined for film or pipe.
Step 3 is the one that separates suppliers. Two masterbatches with identical formulations on paper can perform completely differently depending on the compounding equipment and the process discipline behind them.
How to choose a masterbatch supplier
Ask these five questions. The answers tell you more than any brochure:
- Which carrier resin will you use for my polymer, and why? A supplier who doesn’t ask what you’re running isn’t formulating, they’re selling from stock.
- How do you hold the colour standard between batches? You want to hear about a retained physical master and instrumental measurement, not visual comparison.
- What’s your filter pressure value on this grade? Critical for film, pipe and geomembrane. A supplier who doesn’t test FPV is telling you something.
- What documentation comes with it? For food contact, toys or pharma you need grade-specific compliance data, not a generic company certificate.
- What happens when a batch is out of spec? Ask before you need to know.
Frequently asked questions
What does masterbatch mean? Masterbatch means a concentrated blend of pigment or additive carried in a plastic resin, supplied as granules and added in small percentages to natural polymer during processing to colour or modify the final product.
What is the difference between masterbatch and pigment? Pigment is the raw colourant powder. Masterbatch is that pigment already dispersed into a carrier resin at high concentration, so it can be dosed cleanly and disperses reliably in your process.
What is a letdown ratio? The proportion of masterbatch added to natural polymer. A 1:50 letdown ratio, or 2%, means 2 kg of masterbatch per 98 kg of resin.
Can masterbatch be used with recycled plastic? Yes, and it’s common. Recycled feedstock varies in base colour batch to batch, so higher-opacity pigment systems are usually needed to cover that variation consistently.
Does masterbatch affect the strength of the finished part? It can, if the carrier resin is incompatible with your base polymer or if pigment is poorly dispersed. Correctly formulated and dispersed masterbatch at normal letdown ratios should not meaningfully affect mechanical properties.
How is masterbatch stored? In sealed bags, dry, away from direct heat. Hygroscopic carriers such as PET, PA and PC absorb moisture and may need drying before use – check the technical data sheet for the specific grade.
Talk to a masterbatch manufacturer
Life Color has manufactured masterbatch in India since 2008, from units at Vasai, Maharashtra and Vapi, Gujarat. ISO 9001:2015 certified, 10,000 MTPA capacity.
Tell us your polymer, your process and what you’re trying to achieve – you’ll get a technical answer.
Request a quote → · +91 97025 21537