Medical moulding - how to get better results

Cheryl Weckle and Michelle McManus, technical services & development – medical applications, Trinseo, discuss how a process approach to moulding can lead to better results

Medical moulders are continually challenged to expand their role into areas such as product design, material selection and parts and product qualification. As their function evolves, many are taking a process approach to their business.  They are considering all the activity surrounding the molding process, determining who and what impacts the process, and, soliciting the involvement of the impacted parties, or stakeholders.  This approach and emphasis on collaboration is crucial to driving efficiencies and ensuring a successful end result.

One of these parties is the resin supplier, the provider of the plastic used to mould the parts / components.  There are two key reasons to include the resin supplier early and often in the development process:

1. For the expertise, insights and past experiences they alone can provide, and

2. To allow the resin supplier the opportunity to gather important information about the end use application and performance requirements that will help better support the OEM with resin recommendations.

Following are ways the resin supplier makes an impact:

Recommendations for product selection

As commodity resins are replaced by more advanced, high-performance materials to meet the complexity of the medical device market, it is often a challenge for moulders to keep up-to-date with technology.  The resin provider, who works with plastics every day, can provide recommendations on the latest innovations and preferred solutions for medical devices.  Although the medical device manufacturer and moulder must decide on the appropriateness of the resin for particular applications, with an understanding of specific application requirements: product performance needs (eg durability, flame retardancy), requirements for sterilisation (eg gamma, electron beam, autoclave), and environmental exposure concerns (eg UV light, chemicals), resin suppliers can suggest material alternatives.  In addition, they can evaluate and suggest whether or not products that are currently being used seem to be most appropriate, guarding against possibly using an over-engineered product, which might add unneeded expense.

Alignment of processes for quality and consistency

Medical devices OEMs are subject to stringent regulatory requirements relative to the devices they manufacture, and the ability to comply, is influenced by materials used in production.  Aware of this, moulders need to go ‘downstream’ to make certain the materials supplied are aligned with production standards and requirements for the medical device market and the specific application, as determined by the OEM. Are the materials biocompatible? Are they properly certified according to ISO and USP standards? Have the materials undergone regulatory evaluations? Are processes aligned to comply? If the resin supplier is kept in the loop, from as early in the process as possible, he or she will make certain to deliver what is required: quality medical grade resins produced under stringent quality guidelines, controlled conditions and validated processes. In addition, the supplier can put processes in place to ensure a consistent, predictable, sustainable supply, which is critical in the medical industry. 

Documentation of regulatory compliance

As part of regulatory requirements, documentation of quality assurance is needed throughout and after the life of the medical devices manufactured.  As with most processes, it is easier establish a method to gather this information upfront during the manufacturing design process than to attempt to recreate a paper trail after the fact. A moulder needs to have a relationship with its resin supplier to make sure this evidence can be produced and delivered to OEMs and / or regulatory bodies, as needed, in a timely and accurate manner. Sometimes a moulder will be disconnected from its supply chain making the procurement of documentation, if it has not been anticipated, stressful and a challenge.  Typical documentation for the industry needs to include Management of Change processes, ie lot traceability, formulation lock, notification of change and extended record and sample retention. 

Expectations for collaboration

Involvement of the resin supplier, early in the process, clearly makes a difference. Obviously, moulders are capable of understanding the aforementioned issues but the fact is, the resin supplier, singularly focused on the materials component of the design process, is in the best position to offer input and deliver on elements that fall into this area of responsibility.

To conclude, it is important to select a resin supplier that offers medical sector expertise, is familiar with the challenges of medical device OEMs, and aligns processes to customer needs and expectations.  The importance of staying engaged and encouraging collaboration with the moulder and others in the production cycle to maximise efficiencies and ensure success is paramount.