News: Plastic Breaks through to Drug Vials
Renew your packages with paperboard content.
Rexam Pharma has introduced multilayer rigid plastic for pharmaceuticals. The technology combines different plastics together to offer mechanical resistance to shock as well as barrier properties.
Patrice Lewko, Rexam Pharma’s global marketing director, explains that the company started looking into alternatives to glass after listening to customers complaining of breakage and for drugs presenting incompatibility with glass. “In the diagnostics market in particular, companies want to avoid breakage in blood handling,” he says. Pharmaceutical and biological companies, too, fear breakage of glass vials and syringes during shipping. They also look for a material that does not show protein adhesion or denaturation.
Rexam developed a specialty process for injection molding containers. “The traditional process for injection blow molding uses one material to preform a thermoplastic hollow tube, the parison, including the neck, then the preform moves to the blow station,” explains Loic Sebileau, Rexam’s U.S. multilayer progam manager. In Rexam’s new process, “one material is injected first, then we start injecting a second material to form a middle layer in between two layers of the first material. The sequential injections occur all in one process, creating a sandwich of materials. Quantities and timings are critical. Everything is precisely controlled through a customized patented manifold.”
Rexam’s MLx process is already under production for bottles; the multilayer technology can also be used to create Rexam’s MLc tubes for diagnostic applications.
Potential materials for the multilayer containers include cyclic olefin polymer (COP), cyclic olefin copolymer (COC), PET, PC, nylon, and others. “Several combinations of polymer materials have been identified for pharmaceutical and biological applications,” says Sebileau. COC, for instance, offers moisture barrier, making it a potential replacement for glass when combined with a good oxygen barrier.
Lewko says multilayer plastic vials and other containers may initially cost more than their glass counterparts. However, “glass often requires a surface treatment, bringing its costs up.” Most importantly, though, “is the advantage of avoiding breakage and improving stability,” he says. “Contamination costs after breakage can be high. Using plastic, companies can run their filling lines more efficiently, and productivity increases significantly.”