Shanghai Semitech New Material Co., Ltd.
Address
1628 Lijing Road, Lingang New Area, 200000, Shanghai, China.
APPLICATION GUIDE
Matting Agent for Automotive Coatings
Precision gloss control for OEM clearcoats, waterborne basecoats, and UV-cured topcoats — without compromising DOI, hardness, or weatherability.
Why Gloss Control Is Critical in Automotive Finishes
Automotive OEM and refinish coatings operate under the most demanding optical and mechanical standards in the coatings industry. A matte or satin clearcoat must deliver uniform gloss reduction at 20° and 60° while preserving distinctness of image (DOI) — the sharp, undistorted reflection that defines premium finish quality. Any matting agent that clouds the film, reduces gloss unevenly, or degrades under UV exposure will fail the finish audit.
GMATT silica matting agents are engineered to meet these requirements across solventborne, waterborne, and UV-cured automotive systems.
Key Performance Requirements
- DOI PreservationHigh DOI (>85) is mandatory for premium clearcoats. GMATT 100 Series uses controlled particle morphology to minimize forward light scattering while achieving target gloss levels.
- Scratch and Mar ResistanceAutomotive surfaces face constant micro-abrasion from washing, dust, and contact. GMATT 200 Series reinforces the film matrix, improving scratch resistance without increasing haze.
- WeatherabilityExterior coatings must resist 1000+ hours of UV and humidity cycling. GMATT silica is chemically inert and does not chalk, yellow, or lose efficiency under QUV exposure.
- Waterborne CompatibilityModern OEM lines use waterborne basecoats and clearcoats. GMATT WB Series provides stable, non-settling dispersion in aqueous systems with consistent gloss output across spray batches.
- UV-Cure CompatibilityUV-cured topcoats for plastic trims and interior surfaces require matting agents that do not inhibit radical cure. GMATT UV Series is optimized for acrylate systems.
Product Selection Guide
| System | Recommended Grade | Typical Dosage | Key Benefit |
|---|---|---|---|
| Solventborne clearcoat (OEM) | GMATT 100 Series | 1.5–3.0% | High DOI, transparency |
| Waterborne clearcoat / basecoat | GMATT WB Series | 2.0–4.0% | Stable aqueous dispersion |
| UV-cured topcoat (plastic trim) | GMATT UV Series | 2.0–5.0% | No cure inhibition, hard film |
| 2K polyurethane refinish | GMATT 200 Series | 2.5–4.0% | Scratch resistance, fast cut |
FORMULATOR TIP
For clearcoat systems where DOI is the primary concern, pre-disperse GMATT 100 in solvent using a high-shear disperser before let-down into the clearcoat base. This prevents agglomerate formation that causes haze at low dosage levels.
Frequently Asked Questions
Will the matting agent reduce DOI in clearcoats?
GMATT 100 Series uses a narrow particle size distribution and treated surface chemistry that minimizes light scattering, preserving DOI values above 85 in most clearcoat systems. Dosage optimization and pre-dispersion are key to achieving target gloss without haze.
How does GMATT perform in waterborne automotive basecoats?
GMATT WB Series is engineered for waterborne systems, with hydrophilic surface treatment that ensures stable dispersion without hard settling. It delivers consistent 60° gloss reduction with no cloudiness or haze in the wet film.
What scratch resistance can I expect in a UV-cured automotive topcoat?
GMATT UV Series is formulated for high-crosslink-density UV systems. Its surface-treated silica reinforces the cured film matrix, achieving scratch resistance greater than 10N by pencil hardness test without sacrificing target gloss levels.