Matrix Powders FAQ

Yes, and it is the main reason size selection matters more than series selection.

Surface area drives how much binder and oil the powder takes up, and how much light it scatters. Going from 6 µm (area 9) to 20 µm (area 2) cuts the surface area by more than four times at the same loading. In practice that means less oil demand, easier wetting, better flow — and visibly less soft-focus, because larger plates scatter less.

If a formula was built around 6 µm and you move to 20 µm to save cost, expect the texture to feel lighter and the coverage to drop. Compensate with a finer soft-focus filler rather than by increasing the boron nitride loading.

Drop the oil absorption first, then the loading, then add back slip.

High-absorption silica removes part of the oil phase along with the sebum, so the film ends up under-plasticised. Moving from a 300 grade to a 200 or 150 grade at the same loading often fixes it without touching the rest of the formula. If you must keep the grade, reduce the loading and make up the oil control with a platy filler.

Slip is the second lever: a small addition of boron nitride or mica restores glide and offsets the dry, draggy feel without giving back the oil control.

Because fines that are not fully dispersed act as light scatterers in the wrong size range — they dull the film instead of whitening it.

Going from a 400 nm grade to a 210 nm grade roughly doubles the number of particles at the same weight, which doubles the demands on dispersion. In a 3-roll mill this usually just means more passes. In a high-speed disperser it can mean the difference between 20 minutes and an hour.

Check the grind gauge reading before blaming the grade. If the reading is above 15 µm, the problem is dispersion, not the powder.

Yes, and it is one of the easier substitutions — 20–40% of the talc is a reasonable starting point.

Both are platy aluminosilicates, so the texture translates without a big reformulation. What changes is that calcined kaolin absorbs more oil and presses harder, so you gain wear and oil control and lose some slip. Adding 2–3% of a spherical or a softer filler usually restores the glide.

Going beyond 40% starts to feel dry, and the whiteness of a calcined grade can shift the shade in a tinted product.

Loose powder 40–70%, pressed powder 25–45%. Talc is usually the base, not an additive.

In loose powder the ceiling is feel: past about 70% the powder starts to fly and the pay-off becomes uneven. In pressed powder the ceiling is strength — talc slides, so a high talc fraction needs more binder to hold the compact together. That is the reason talc-reduced compacts exist as a category.

If your compact chips, the first thing to check is the talc-to-binder ratio, not the talc grade.

Yes — Kingcovite 6710 at 10 µm, held to the German BVL heavy-metal limits.

It sits in the synthetic fluorphlogopite group, which is where the strictest market requirements usually land, because the synthetic route makes the heavy-metal profile easier to control in the first place. The optical performance is the same as the standard 10 µm grade.

If a customer questionnaire names BVL, this is the grade to quote.

Yes, but for a different reason than in powders. In liquids it is a texture and slip modifier, not a structure former.

The plates orient during application and reduce the drag you get from high oil-absorption fillers, which is why foundations containing it spread more evenly and feel less dry. Typical use is 1–5%. Above that, the low oil absorption starts to work against you in an emulsion, and you may see viscosity drop or a slight gloss increase.

In lip products it is used at low levels for glide and to reduce the waxy drag of the base. Because it is inert and has no colour of its own, it does not shift the shade.

Wet it out before it goes into the main batch, and keep the shear high enough while it disperses.

Spherical porous silica has a large internal pore volume, so it pulls binder and oil into the pores quickly and forms lumps that are hard to break down later. Adding it into a portion of the oil phase first, or under higher shear than the rest of the batch, usually resolves it. Adding it last into a low-shear batch is the most common cause.

If agglomeration appears only after storage rather than during making, the cause is usually insufficient wetting rather than the grade, and changing grade will not fix it.

Less, and the gap is bigger than most people expect.

TiO2 needs air voids around the particle to scatter efficiently. In an anhydrous base the oil wets the surface only partially, leaving those voids; in a water-based or heavily wetted system the film is more continuous and the refractive index step at the particle surface is smaller, so the same loading looks less opaque.

In practice you compensate by loading 10–20% more in water-based systems, or by pairing it with a platy filler that adds its own scattering.

The specification holds whiteness within a defined band, but calcined kaolin is a natural-mineral product, so there is lot-to-lot variation inside that band.

For a tinted product, that matters more than the nominal number: a 1–2 point shift in whiteness in a low-pigment formula is visible. The practical answer is to qualify two or three lots against your own colorimetric standard before locking the formula, and to ask for the COA of the specific lot on each reorder.

If the shade is critical, a synthetic filler gives you a tighter window at a higher cost.

Reduce the fine fraction and control humidity, in that order.

Airborne dust during filling is mostly the sub-10 µm fraction, and a coarse grade such as LS-325 generates noticeably less of it than a 5 µm oil-control grade. Where the grade is fixed by the formula, holding the filling room at 45–55% RH and grounding the equipment removes most of the rest.

Agglomerating the powder or using a coated grade also helps, but that changes the feel and is a bigger decision than humidity control.

Eyeshadow 20–50%, face powder 5–25%.

In eyeshadow, mica is often the structural base — it provides the press strength, the pay-off and the pearl, and the pigment sits on top of it. Below 20% the shadow loses its cohesion; above 50% you start to lose colour intensity because the pearl dilutes it.

In a face powder, mica is usually a supporting player: enough to add slip and a soft sheen, not so much that the product looks frosted. Above roughly 25% in a translucent powder, the pearl becomes visible on the skin in daylight.

Every lot ships with a COA reporting the specification figures for that batch, including the soluble boron figure for that grade — quoted as soluble borate % on the 7000 and 3000 series and as boron leaching ppm on the 9000 series. TDS and SDS are available per grade.

For questionnaires we can support with the composition and CAS information, the specification limits, and the soluble boron figure per lot. What we do not do is issue a REACH registration statement on the customer's behalf — whether a substance needs registering depends on your tonnage and role in the supply chain, and that determination is yours or your OR's to make.

If you tell us the destination market and the exact wording your customer needs, we can tell you which of those we can answer directly and which you will need to resolve locally.

COA per lot, TDS and SDS are the baseline. Beyond that, the requirement depends on the form and on how the customer's own product is classified.

Two questions come up most often. First, whether the material counts as a nanomaterial for the customer's market — that depends on the particle size distribution of the specific grade, so it has to be answered per grade against the definition in force, not per product family. Second, crystalline silica content, which customers ask about for inhalation and labelling reasons; amorphous grades are specified and reported separately from crystalline.

As with any regulatory answer, tell us the destination and the wording your customer uses, and we will tell you which parts we can support from the batch documents.

A batch COA, the TDS, and the SDS. Additional documents — heavy metal statements, allergen declarations, non-nano statements, REACH registration status — are issued on request against the specific grade and lot.

The COA is the document that matters for release testing, because it reports the measured values for that lot rather than the specification range. Ask for the COA of the lot being shipped, not a generic datasheet for the grade.

We do not put market-specific limit values in the TDS. They change, and a stale number in a technical document is worse than no number at all.