How to Choose a Masterbatch Supplier: A 12-Point Checklist

Most masterbatch supplier decisions are made on two things: a price, and a sample that looked acceptable. Both are poor predictors of what delivery number eight will be like.

This is the checklist we would use if we were buying rather than selling. Twelve points, each with what a good answer actually sounds like.

1. Do they extrude it themselves?

The single most useful question, because it determines whether anyone in the conversation can fix a problem.

A compounder owns the formulation and the process. A trader resells somebody else’s finished product. Both can be legitimate businesses, but only one can tell you why your batch ran off shade.

Good answer: “Yes, on our own twin-screw line, and we hold the formulation.” Warning sign: a change of subject to certifications or delivery performance.

2. How do they verify dispersion?

Pigment arrives as agglomerates. Compounding breaks them down and distributes them. Get this wrong and you see specks, streaks, screen-pack blockage, shade inconsistency at a fixed let-down ratio, and underperforming UV protection.

Filter pressure value testing is the standard check: push a known mass through a fine screen, measure the pressure rise, and a high rise means undispersed material. It is difficult to fudge.

Good answer: a filter pressure value for your grade, offered without being pushed. Warning sign: “our dispersion is excellent.”

3. Do they retain a physical master standard?

If you buy colour, you are buying repeatability. A retained physical standard — a plaque kept under controlled conditions that every future batch is measured against — is how repeatability is actually delivered.

Good answer: “We retain a plaque for your colour and measure every batch against it.” Warning sign: matching against your original sample, which will yellow, scratch and drift.

4. Can they state illuminant and geometry?

Colour measurement is meaningless without the conditions. A tolerance of ΔE 1.0 means nothing until you know which ΔE formula, under which illuminant, at what observer angle, specular included or excluded.

Good answer: “ΔE*00 under D65/10°, specular included.” Warning sign: “ΔE under 1” with no further detail. See Delta E and colour tolerance.

5. Do they ask what polymer you run?

Masterbatch is colourant carried in a polymer. Carrier and base resin have to be compatible or you get poor dispersion, weak weld lines, or haze where you needed clarity.

A supplier who quotes before asking what you run is selling a catalogue item. A supplier who asks for your resin grade is doing the job.

Good answer: questions about polymer, grade, MFI and process before any number is quoted. Warning sign: a “universal” masterbatch for every application.

6. Will they match in your resin, not theirs?

The same colourant gives a different result in a different base resin, and sometimes a visibly different one. Matching in the supplier’s house resin and then shipping into yours is a common cause of a first production run that does not look like the approved sample.

Good answer: “Send us your resin and we will match in it.”

7. Can they produce a grade-level compliance declaration?

This is where a lot of buying goes wrong. A company ISO certificate says a quality system exists. It says nothing about whether this grade is suitable for food contact, a toy, or an exported electrical part.

What you need depends on the end market:

End application	Ask for
Food contact	FSSAI and the applicable IS specifications for the polymer
Toys and childcare	EN 71-3 heavy-metal migration, IS 9873
EU export	REACH, plus RoHS for anything electrical
Electrical and electronic	RoHS and the end-standard flammability requirement

Good answer: a declaration naming your grade. Warning sign: a company certificate offered as though it answers the question.

8. What happens on batch two?

Every supplier makes the first batch carefully. You are buying the twentieth.

Good answer: a described process — retained standard, batch records, release testing against a tolerance. Warning sign: reassurance without a mechanism.

9. What is their typical batch size and changeover rhythm?

Not a capacity question — a fit question. A plant geared to long commodity runs will find your twelve-colour short-run programme expensive to serve, and will price accordingly. A plant built around frequent changeovers may not be competitive on a single high-volume shade.

Good answer: a straight description of how their line actually runs.

10. Who answers when something goes wrong?

The most important service question in this industry, and the least asked. A colour or dispersion problem is usually discovered mid-run, on your line, with material in the hopper.

Good answer: a named technical contact who has seen a plant floor. Warning sign: everything routed through a sales desk.

11. Can you visit?

A plant visit answers more in two hours than six months of correspondence. You are looking at raw-material storage, whether the lab has a spectrophotometer that is actually used, whether retained standards exist and are filed properly, and whether the changeover and purge discipline matches what you were told.

Good answer: yes, come.

12. Will they tell you when their product is not the right answer?

The most reliable signal of all. A supplier who says “for that application you want a mono concentrate rather than a matched colour, and here is why” is thinking about your process. A supplier who says yes to everything is thinking about the order.

How to weight these

Not all twelve matter equally, and the weighting depends on what you buy.

If you buy commodity black or white in volume: dispersion (2), consistency (8) and compliance (7) dominate. Colour management matters less because the shade is not the variable.

If you buy matched colour: 3, 4, 5 and 6 are the whole decision. Everything else is secondary to whether delivery twenty matches delivery one.

If you buy additive masterbatch: 2 and 7 dominate, because dispersion determines whether the additive actually functions and compliance determines whether you can sell the part.

If you run short runs in many colours: 9 and 10 will decide whether the relationship works, regardless of how good the product is.

A sensible sequence

1. Send a brief complete enough to quote against — polymer and grade, process, part geometry, colour standard, end market, annual volume.
2. Compare the questions that come back, not just the prices. The supplier who asks the most is usually the one who will cause you the least trouble.
3. Run a trial against your own resin on your own line, and measure it. See how to run a masterbatch trial.
4. Check batches two and three before committing the programme.
5. Visit, if the volume justifies it.

Talk to us

We would rather be evaluated on this checklist than on a price list.

We extrude on our own lines at Vasai under ISO 9001:2015, retain a physical master standard for every matched colour, and verify dispersion by filter pressure value. We will match in your resin, and we will tell you when a mono concentrate or a different product is the better answer.

Send us your polymer and grade, your process and your annual volume and we will come back with a specification and a trial proposal. Related: colour masterbatches, white masterbatches, additive masterbatches, mono concentrates, about us.

Frequently asked questions

What is the most important thing to check when choosing a masterbatch supplier?

Whether they extrude the product themselves and hold the formulation. It determines whether anyone in the relationship is able to diagnose and correct a dispersion or colour problem, and every other answer depends on it.

How can I tell if a masterbatch supplier is a manufacturer or a trader?

Ask whether they extrude the grade on their own line and hold the formulation. A manufacturer will answer directly and will usually volunteer process detail. A trader tends to redirect to certifications, stock availability or delivery performance.

What is filter pressure value testing?

A dispersion check. A known mass of masterbatch is pushed through a fine screen and the pressure rise is measured. Undispersed pigment agglomerates block the screen and drive the pressure up, so a low value indicates good dispersion. It is the most difficult number in this industry to argue with.

Why should the supplier match colour in my resin rather than their own?

Because the same colourant looks different in a different base polymer. Matching in a house resin and shipping into yours is a common reason a first production run fails to match an approved sample.

Is an ISO 9001 certificate enough for food-contact or toy applications?

No. ISO 9001:2015 certifies the quality management system. Food contact, toy safety and RoHS each need a declaration against the relevant standard for your specific grade. A company certificate is not a substitute for a grade-level document.

How many samples should I test before switching masterbatch supplier?

At least three separate deliveries, not three samples from one batch. Any supplier can make one good batch. What you are buying is consistency, and it only becomes visible across production lots.

What should I look for on a masterbatch plant visit?

Raw-material storage conditions, whether the lab spectrophotometer is in routine use rather than on display, whether retained colour standards exist and are filed properly, and whether changeover and purge discipline matches what you were told on the phone.

Should I choose the cheapest masterbatch quote?

Only after normalising for let-down ratio. A cheaper masterbatch used at a higher dosage can cost more per part, and poor dispersion carries hidden costs in scrap, screen changes and downtime that never appear on the invoice.