Dry-Blend Incorporation into Powder Coating Batches
Unlike liquid coatings that require dispersant-mediated wetting of silica into a solvent or water medium, powder coatings incorporate matting agents as a dry premix before extrusion. GMATT 600 is a free-flowing precipitated silica powder with particle morphology and size (d50 5–15 µm) optimised for the dry-blend stage of powder coating compounding. At 1.5–4.0 wt% addition to the powder premix, GMATT 600 distributes uniformly, passes through the extrusion shear without structure breakdown, and emerges from the grinding stage at the correct particle size for the target application DFT of 60–100 µm.
Consistent Gloss Reduction Independent of Cure Temperature History
Wax-based matting agents for powder coatings create incompatible phases at the film surface during cool-down — a mechanism sensitive to cure oven profile, DFT, and panel mass. GMATT 600 works by a purely mechanical film-surface disruption mechanism that is thermally stable through the full 180–220°C cure window. This means the 60° gloss result at 2.0–4.0 wt% loading is consistent across different oven zones, DFT variations from thin sections to heavy profiles, and seasonal ambient temperature changes — reducing the need for mid-production gloss calibration.
Zero VOC, Zero Solvent for Sustainable Powder Production
Powder coatings hold their market position largely due to zero-VOC, zero-solvent status. GMATT 600 is an inorganic synthetic amorphous silica that contributes zero VOC, zero solvents, and zero heavy metals to the powder formulation. It is REACH-compliant and RoHS-compatible, supporting powder coating manufacturers who supply automotive, architectural, and electronics OEMs with VOC-free compliance documentation. This positions GMATT 600 as the matting agent of choice for powder coatings targeting EU Ecolabel or similar environmental certifications.
Outdoor Durability in TGIC and HAA Polyester Systems
Powder coatings for outdoor applications (architectural aluminium extrusion, garden furniture, outdoor structures) use TGIC or HAA polyester binders evaluated under QUALICOAT and GSB standards. GMATT 600 silica is UV-stable, non-chalking, and does not accelerate colour fade in polyester or superdurable polyester binder systems. At 2.0–3.0 wt% in polyester TGIC powder at 60–80 µm DFT, GMATT 600 delivers matte appearance (60° gloss 10–25 GU) without impairing the cross-hatch adhesion, impact resistance, or weathering resistance of the QUALICOAT-qualified system.
When to Use GMATT 600 for Powder Coatings
GMATT 600's temperature-independent matting mechanism and dry-blend compatibility make it suitable across the full range of thermoset powder coating chemistries — from interior epoxy to outdoor superdurable polyester.
| Scenario | Recommended Grade | Target DFT | Loading |
|---|---|---|---|
| Epoxy-polyester hybrid, interior | GMATT 600 | 60–100 µm | 2.0–4.0 wt% |
| Polyester TGIC, architectural outdoor | GMATT 600 | 60–80 µm | 2.0–3.0 wt% |
| Polyurethane powder, matte | GMATT 600 | 50–80 µm | 2.0–3.5 wt% |
| Pure epoxy powder, anti-corrosion | GMATT 600 | 80–150 µm | 2.5–4.5 wt% |
| Superdurable polyester powder | GMATT 600 | 60–80 µm | 2.0–3.0 wt% |
Technical FAQ
GMATT 600 formulation and processing questions for thermoset powder coating applications.
+How is GMATT 600 incorporated into powder coating batches?
GMATT 600 is added as a dry-blend into the powder coating premix before the extrusion step. Typical addition is 1.5–4.0 wt% of the total powder batch. Because GMATT 600 is a precipitated silica powder with free-flowing particle morphology, it distributes uniformly through the premix without clumping, and its particle size (d50 5–15 µm) is compatible with the extrusion shear used in standard powder coating compounding lines. Post-extrusion grinding maintains GMATT 600 particles within the desired size range for the application DFT.
+What gloss targets does GMATT 600 achieve in epoxy-polyester hybrid powder coatings at 60–100 µm DFT?
In thermoset epoxy-polyester hybrid powder coatings cured at 180–200°C (60–100 µm DFT), GMATT 600 at 2.0–4.0 wt% achieves 60° gloss targets of 10–40 GU. The high oil absorption of GMATT 600 provides efficient gloss reduction per unit mass, allowing formulators to achieve deep matte (10–20 GU) at 3.0–4.0 wt% loading without compromising the smooth film flow required for powder coatings on complex profiles.
+Is GMATT 600 thermally stable through 200–220°C powder coating cure cycles?
Yes. Synthetic amorphous silica (SAS) is thermally stable to above 600°C in isolation. GMATT 600 undergoes no phase transformation, colour change, or structural degradation at the 180–220°C cure temperatures used in standard thermoset powder coating formulations (epoxy, polyester TGIC, polyurethane powder). The silica particles remain chemically inert through repeated cure cycles, which is important for reclaim powder systems where partially-cured material is returned to the batch.
+How does GMATT 600 compare to wax-based matting agents for powder coatings?
Wax-based matting agents for powder coatings (PTFE wax, polyethylene wax) work by forming an incompatible phase at the film surface during cooling. Their effectiveness is highly sensitive to cure temperature and cool-down rate, leading to batch-to-batch gloss variation. GMATT 600 works by a purely mechanical film-surface disruption mechanism that is independent of temperature history, providing more consistent gloss across different cure oven zones, DFT variations, and seasonal temperature changes.
+Can GMATT 600 be used in polyester TGIC powder coatings for outdoor applications?
Yes. GMATT 600 is compatible with polyester TGIC (triglycidyl isocyanurate) and polyester HAA powder coatings for outdoor durable applications (QUALICOAT Class 1 and Class 2 systems). The silica is UV-stable and does not contribute to chalking or colour fade under weathering. In superdurable polyester powder at 60–80 µm DFT, GMATT 600 at 2.0–3.0 wt% achieves matte appearance (60° 10–25 GU) without impairing the weathering resistance of the polyester binder.
Recommended Solution
For thermoset powder coatings requiring consistent matte appearance at 180–220°C cure with zero VOC contribution, specify GMATT 600 Series — high-efficiency precipitated silica with temperature-independent matting performance.
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