Colloidal graphite

When selecting colloidal graphite, the most critical factor is particle size distribution, typically measured in microns (µm). For high-precision lubrication or conductive coatings, look for sub-micron particles (<1µm) to ensure stability and prevent settling. Additionally, verify the solid content percentage (usually 10% to 30%) and the pH value, as these affect the dispersion's compatibility with your specific application environment.

Colloidal graphite is generally dispersed in water, oil, or alcohol. Water-based dispersions are preferred for environmentally sensitive projects and forging applications due to their non-flammable nature. Oil-based versions are ideal for high-temperature machinery lubrication where moisture must be avoided. Alcohol-based (solvent) dispersions are best for quick-drying conductive coatings in electronics.

A high-quality product must demonstrate excellent suspension stability; the graphite should not settle into a hard cake at the bottom of the container. It should also provide a low coefficient of friction (typically <0.1) and high thermal stability, maintaining its lubricating properties at temperatures exceeding 450°C in oxidizing atmospheres or up to 2000°C in inert environments.

Suppliers must provide a comprehensive Material Safety Data Sheet (MSDS/SDS). For international trade, ensure the product complies with REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) for the EU market. If used in food-grade machinery, verify NSF H1 or H2 certification. Always check the HS Code (typically 3801.20) to ensure correct customs classification.

The main risk is leakage and temperature sensitivity. Colloidal graphite is often classified as non-hazardous, but as a liquid, it requires UN-approved packaging (drums or IBC tanks) to prevent spills. Furthermore, water-based dispersions can be ruined if they freeze during transit; ensure your logistics provider uses temperature-controlled containers if shipping through cold climates.

Prioritize Audited Suppliers who have undergone on-site inspections by third-party organizations like SGS or Intertek. Review their Business License and Export Qualifications. It is highly recommended to request a Certificate of Analysis (COA) for the specific batch before shipment to ensure the chemical composition matches your requirements.

Negotiate based on volume-tiered pricing; chemical manufacturers often offer significant discounts for FCL (Full Container Load) compared to LCL. Discuss payment terms such as a 30% deposit and 70% against the Bill of Lading (B/L). Additionally, ask for a sample for lab testing (usually 500ml - 1L) to validate the dispersion quality before committing to a large contract.

Always use secure payment methods and avoid direct transfers to private bank accounts. Utilize inspection services at the loading port to verify that the drum seals are intact and the quantity is correct. Ensure the Incoterms (e.g., CIF or FOB) are clearly defined in the sales contract to establish exactly where the risk transfers from the seller to the buyer.