Composite Adhesives For Pharmaceutical Flexible Packaging And Their Performance Requirements | Donglin Packaging

The pharmaceutical industry represents a crucial application area for flexible packaging. In recent years, the growing aging population, an increase in acute and chronic diseases, the impact of the COVID-19 pandemic, and reforms in healthcare systems have led to a rising demand for pharmaceuticals. This trend has propelled rapid growth in the pharmaceutical industry, significantly boosting the development of pharmaceutical packaging. The demand for flexible pharmaceutical packaging is expected to grow annually at a rate of 6%, reaching a market size of billions of dollors by 2024.

As the pharmaceutical flexible packaging industry rapidly evolves, there are escalating demands for performance and safety standards. Due to the essential need for long-term protection of packaged pharmaceuticals, pharmaceutical flexible packaging typically involves multi-layer composite structures. Adhesives have become a crucial material in pharmaceutical flexible packaging.

I. Types and Structures of Pharmaceutical Flexible Packaging

Pharmaceutical flexible packaging offers a wealth of material choices, advanced technologies, automation, high production efficiency, low energy consumption, and excellent sealing properties. Various forms of pharmaceutical flexible packaging exist, utilizing different materials. Some pharmaceutical flexible packaging types that require the use of composite adhesives include:

1. Pouch Packaging: Mainly used for tablets, granules, powders, bulk drugs, ointments, and infusion preparations. The main packaging structures include paper-plastic, paper-aluminum-plastic, plastic-plastic, aluminum-coated, and aluminum-plastic. Film rolls are supplied to pharmaceutical manufacturers, who then use automatic packaging machines for bag-making, filling, sealing, and cutting, achieving high-speed automated pharmaceutical packaging.
2. Strip Packaging: Suitable for bulk automatic packaging of various shapes and sizes of drugs, particularly suitable for larger dosage forms, highly diluted drugs, photosensitive drugs, heat and cold-resistant drugs, and drugs with long shelf lives. The main material used is SP composite film, specifically polyethylene-aluminum-plastic composite film, supplied in roll form. Pharmaceutical manufacturers place the drugs between two layers of SP film and then heat-seal them, leaving indentations between the drugs.
3. Double Aluminum Foil Packaging: Similar to strip packaging but employs two layers of coated aluminum foil (usually 17μ) instead of SP film. The application method is the same.
4. Blister Packaging: Classified into aluminum-plastic type, aluminum-plastic-aluminum type, and aluminum-aluminum type based on different composite structures. The aluminum-plastic type involves vacuum thermoforming of PVC rigid sheets, filling the drugs, and heat-sealing with PTP aluminum foil (aluminum foil coated with VC resin). The aluminum-plastic-aluminum type (PTP tropical aluminum) includes adding an additional layer of aluminum-plastic behind the PVC blister pack, followed by heat-sealing after thermoforming. The aluminum-aluminum type (cold-formed aluminum) involves cold punching PA/AL/PVC aluminum-plastic rigid sheets and heat-sealing with PTP aluminum foil.

II. Performance Requirements for Composite Adhesives in Pharmaceutical Flexible Packaging

The barrier properties and safety of pharmaceutical flexible packaging directly impact the quality and safety of pharmaceuticals. Apart from the thin film materials used in pharmaceutical flexible packaging, composite adhesives, as key materials in pharmaceutical flexible packaging, significantly influence the quality and performance of the materials. Several standards related to composite adhesive properties in pharmaceutical packaging include:

• YBB00132002: Guidelines for Composite Films and Bags for Pharmaceutical Packaging
• YBB00172002: Polyester/Aluminum/Polyethylene Composite Films and Bags for Pharmaceutical Packaging
• YBB00182002: Polyester/Low-Density Polyethylene Composite Films and Bags for Pharmaceutical Packaging
• YBB00242002: Polyamide/Aluminum/Polyvinyl Chloride Cold-Formed Solid Pharmaceutical Composite Sheets
• YBB00182004: Aluminum/Polyethylene Cold-Formed Solid Pharmaceutical Composite Sheets
• YBB00202004: Glassine Paper/Aluminum/Polyethylene Composite Films and Bags for Pharmaceutical Packaging
• YBB00212004: Guidelines for Aluminum-Plastic Sealing Gaskets for Pharmaceutical Packaging

The performance requirements for composite adhesives in pharmaceutical flexible packaging primarily include:

1. Mechanical Properties: The composite base materials should have excellent adhesion strength, peel strength, and heat-sealing strength, meeting the requirements of YBB standards.
2. High-Temperature Resistance: The composite film should possess outstanding high-temperature resistance to meet the demands of roll-to-roll automatic packaging machines.
3. Safety: The composite film should meet safety requirements outlined in YBB standards, such as solvent residue, easily oxidizable substances, and leachables.
4. Other Functional Requirements: For products like cold-formed aluminum, exceptional deep-drawing resistance is necessary.

In conclusion, pharmaceutical flexible packaging demands advanced materials and technologies, with composite adhesives playing a pivotal role in ensuring the safety and efficacy of pharmaceutical products. Compliance with rigorous standards is crucial in meeting the ever-growing demands of the pharmaceutical industry.