Plastic bottle for capsules

The most common materials are HDPE (High-Density Polyethylene) and PET (Polyethylene Terephthalate). HDPE is preferred for its excellent moisture barrier properties and chemical resistance, making it ideal for long-term supplement storage. PET offers high clarity (glass-like appearance) and impact resistance, which is better for brand visibility. For eco-conscious brands, PCR (Post-Consumer Recycled) plastics are increasingly available to meet sustainability goals.

Suppliers must provide FDA (Food and Drug Administration) or EFSA (European Food Safety Authority) compliance certificates for food-contact safety. Key certifications include ISO 15378, which specifically governs primary packaging materials for medicinal products, and BPA-Free certification. If the product is for the US market, ensure the closures meet CPSC (Consumer Product Safety Commission) standards for Child-Resistant (CR) packaging.

To protect light-sensitive ingredients, specify UV-inhibitors or choose opaque colors like Amber, Cobalt Blue, or Solid White. For moisture-sensitive capsules, verify the induction sealing compatibility of the bottle neck. High-quality suppliers on Made-in-China.com can provide integrated desiccant caps or suggest specific wall thickness (typically 1.0mm to 1.5mm) to reduce oxygen transmission rates.

Standardization is key for automation. Confirm the GPI/SPI neck finish standards (e.g., 38-400 or 45-400). Ensure the thread depth and pitch are consistent to prevent leaks or torque failures during high-speed capping. Request a tolerance report showing a variance of no more than ±0.2mm on critical dimensions.

Request a Pre-Shipment Inspection (PSI) focusing on heavy metal testing and microbial limits. Use the Secured Trading services on Made-in-China.com to ensure payment is only released after the quality report is verified. Always ask for a Certificate of Analysis (COA) for every production lot to ensure no regrind material was used beyond the agreed percentage.

Focus on mold ownership and maintenance. If you require a custom shape, negotiate for the supplier to absorb the mold cost if the annual order volume exceeds a certain threshold (e.g., 100,000 units). Additionally, request tiered pricing where the unit cost drops by 10-15% as you move from a 20ft container to a 40ft High Cube container.

Empty bottles are 'shipping air,' so volumetric weight will significantly impact costs. Negotiate for nested packaging if the design allows, or use high-compression outer cartons to prevent crushing during sea freight. Ensure the supplier uses PE inner bags to prevent dust and static accumulation during transit, which is critical for clean-room filling environments.

Prioritize 'Audited Suppliers' who have undergone on-site verification by third-party agencies like SGS or Bureau Veritas. Check their Audit Report for their production capacity, R&D capabilities, and quality management systems. A supplier with a long-standing history (5+ years) on the platform typically indicates higher reliability in international trade.