Furnace and channel blacks chosen on depth of black, undertone and structure — pigment that has to stay black under processing heat and years of daylight.
Particle size decides how deep it looks; structure decides just about everything else.
Finer particles scatter less light and absorb more, giving a deeper, blue-toned black. They also clump together more, need more energy to break apart, and push viscosity up at a given loading. Coarser grades mix in easily and cost less, but give a browner undertone and less tinting strength. The right grade is whichever one your equipment can actually mix in properly.
13–30
nm primary particle size
From high-jet channel-type blacks to the regular furnace range.
Colour is made at the mill, not in the bag.
Particle size and structure are matched to the system and to the mixing equipment on hand, before any trial run. This is where most black problems are avoided.
The pigment is wetted into the base with a suitable dispersant. Surface treatment and pH decide how easily this happens and how stable the result stays afterward.
Clumps are broken down under controlled shear, and the process is judged by a fineness check and colour development, not by how long it ran.
The batch is checked against the standard for depth, undertone and tint strength, and released to a set tolerance so the next batch matches this one.
Particle size and form are chosen against the system and the equipment.
Fine particle · high colour
The deepest, bluest black in the range, for automotive topcoats and premium coatings where a deep black is the whole point and the plant has the mixing power to deliver it.
Medium particle · balanced
The everyday grade for general coatings, inks and plastics. Good depth of black, easy to mix in, and a price that suits volume production.
Pelletised · low dust
Densified into free-flowing beads for automatic weighing and clean handling. Suited to compounding, where the extruder supplies the shear to break them apart.
No single number tells the whole story.
The governing property. Finer particles absorb more light and give a deeper, bluer black — and need proportionally more mixing energy.
The measured depth of black in a full film. This is the figure a premium coating is bought on, and it separates grades a shade card cannot tell apart.
Whether the black reads blue or brown at the edge of the film. It carries through into every tint made from it, and cannot be fixed later without cost.
A practical measure of structure. It sets how much binder the pigment needs, and so the viscosity and maximum loading a formulation can carry.
Reflects surface chemistry from the manufacturing process. Higher volatiles help wetting in polar systems, but are avoided where processing heat would release them.
Coarse particles that survive into the finished film as visible specks. This figure decides suitability for thin films and fine printing.
Particle size, above everything else. Smaller particles absorb more light and scatter less, giving a deeper black with a blue undertone. The trade-off is that finer grades are harder to mix in and raise viscosity faster at the same loading.
Structure describes how far the tiny particles are fused into branched clusters. High structure needs more binder and raises viscosity, but mixes in more easily and conducts electricity better. Low structure gives a deeper black and easier flow. Oil absorption is how it is measured in practice.
Beaded grades flow, dose and handle cleanly with far less dust, and suit compounding where an extruder supplies the shear to break them apart. Powder grades wet in faster and suit liquid systems with limited mixing power. The equipment on hand usually decides.
Yes. Fine-particle blacks at just a few percent loading are among the most effective UV stabilisers available for polyolefins, which is why pipe and geomembrane compounds are specified on both particle size and dispersion, not colour alone.
Every lot is checked against a retained standard for depth of black, undertone and tint strength, and released within a set tolerance. The figures travel on the certificate of analysis so a formulation can be requalified against data, not by eye.
Send us your system, target depth of black and the mixing equipment you have. We will come back with the grade, loading and let-down ratio your formulation needs.
