Aluminium pigment for coating

Selecting the correct pigment depends on the desired finish. Non-leafing pigments are distributed evenly throughout the coating film, providing good adhesion and a metallic sparkle or polychromatic effect, making them ideal for automotive and industrial coatings. Leafing pigments float to the surface, creating a chrome-like, mirror-smooth finish with high brilliance, often used in decorative paints and roof coatings.

Buyers must focus on Particle Size Distribution (D50), as finer particles provide higher opacity and a smoother finish, while coarser particles offer more 'sparkle.' Additionally, verify the solid content (typically 65%-75%) and the solvent type (e.g., Mineral Spirit or High Flash Naphtha) to ensure compatibility with your coating system. For water-borne systems, ensure the pigment is silica-encapsulated or chemically passivated to prevent hydrogen gas evolution.

Aluminium pigments are often classified as Hazardous Goods (Class 4.1 Flammable Solids). Ensure the supplier provides a valid Material Safety Data Sheet (MSDS) and complies with REACH (EU) or TSCA (US) regulations. For food-contact packaging coatings, the pigment must meet FDA or EU 10/2011 migration standards.

Cornflake pigments have irregular edges and provide high hiding power at a lower cost. In contrast, Silver Dollar pigments have a smooth, circular surface that reflects light more uniformly, resulting in superior brightness, 'flop' effect (color change at different angles), and higher distinctness of image (DOI).

The biggest risk is moisture contamination, which can react with aluminium to produce hydrogen gas, leading to drum swelling or explosions. Always insist on UN-approved steel drums with airtight plastic liners. Ensure the cargo is stored in a cool, ventilated area away from oxidizing agents and acids during transit.

Prioritize Audited Suppliers who have undergone third-party onsite inspections by SGS or TÜV Rheinland. Check for ISO 9001 (Quality Management) and ISO 14001 (Environmental Management) certifications. Request a COA (Certificate of Analysis) for every batch to ensure consistency between the sample and the bulk order.

Since aluminium prices fluctuate with the LME (London Metal Exchange), consider negotiating a formula-based pricing model for long-term contracts. For initial orders, request a 2-5kg sample for lab testing; reputable suppliers usually provide samples for free, though buyers may cover the hazardous material express fee.

Ensure the HS Code (typically 321290) is correctly declared. Because it is a flammable solid, you must provide a Dangerous Goods (DG) Certificate and a Safe Transport of Chemical Goods Certificate. Failure to provide these can lead to heavy fines or the shipment being seized at the port of entry.