White fused alumina grades commonly used for fluorocarbon weather-resistant topcoat
Fluorocarbon coatings are cured at high baking temperature (230–260°C). Na₂O is the primary control index. Excessive sodium may cause blistering, loss of gloss, poor weather resistance and degraded salt spray performance. High iron content leads to yellowing and color shift, which is particularly critical for light-colored or white fluorocarbon topcoats.
Key specifications for fluorocarbon-coating grade:
Al₂O₃ ≥99.5%
Na₂O ≤0.2% (≤0.15% preferred for high-end fluorocarbon orders)
Fe₂O₃ ≤0.05%
Crystal phase: α‑Al₂O₃ with low β-phase content
Processing: hydraulically classified, iron removed, low oil absorption, good dispersion, compatible with PVDF fluorocarbon resin systems.
Common particle sizes sorted by finish requirement:
Matte / semi-matte fluorocarbon topcoat (highest sales volume): 800#, 1000#, 1200#
D50: 14 μm, 11.5 μm, 9.5 μm
Application: fluorocarbon paint for aluminum curtain wall panels and profiles, used for matting and improving scratch resistance without obvious surface roughening.
High-gloss clear coat & light transparent fluorocarbon: 1500#, 2000#
D50: 8 μm, 6.7 μm
Ultra-fine powder, soft matting effect, no gloss reduction, balancing scratch resistance, UV resistance and chalking resistance.
Heavy-duty anti-corrosion & wear-resistant fluorocarbon (construction machinery, guardrails): 600#
D50: 20 μm, higher abrasion resistance, mostly for intermediate coat or h