Solvay Develops Innovative Design Concepts for Production of Sterilisation Cases and Trays
Solvay Specialty Polymers has contracted with polymer design, engineering, and injection moulding firm Promoulding BV, the Netherlands, to generate several original design concepts for the manufacturing of sterilization instrument cases and trays using Radel (trademarked) polyphenylsulfone (PPSU) resin instead of stainless steel or aluminum. These concepts were unveiled March 21 at the American Academy of Orthopedic Surgeons (AAOS) in Chicago, USA, and are being shared globally with case and tray manufacturers and medical OEMs.
The first concept takes advantage of the cost efficiencies of injection moulding versus thermoforming, which has been the standard manufacturing method for this application since the mid-1990s. Responding to growing cost pressures from medical OEMs, this injection moulding concept uses just five moulded components to build full DIN, ¾ DIN, or ½ DIN cases.
High hole count, which is facilitated by injection moulding and difficult to achieve after thermoforming, reduces surface area to avoid wet-pack and further lowers overall case weight versus metal. Snap-fit features allow quick assembly, and unlike thermoforming, a matte surface finish can be readily achieved to reduce glare from operating room lights. The use of coloured resins allows for branding opportunities without the added cost of anodising metal, and material transparency offers another design option.
The second concept offers an innovative strategy for positioning and securing instruments in the inner tray. Instruments are first laid in a pin-bed for positioning. The surface topography is then computer scanned and replicated using automated CNC equipment onto the surface of a honeycomb insert which has been moulded or extruded from Radel PPSU. The honeycomb structure provides exceptional strength in the vertical direction for supporting large instruments, while inserts with varying cell sizes can be used to accommodate smaller instruments.
This system speeds time-to-market after instrument design is complete, with future instrument modifications easily incorporated without the need to reconfigure brackets or rebuild the tool. Radel PPSU is the material of choice for sterilization cases and trays because of its toughness, excellent chemical resistance, and ability to withstand repeated disinfection and autoclaving – over 1,000 cycles—while maintaining its toughness and impact resistance.
Solvay Specialty Polymers has been granted design protection for these concepts in North America, Europe, and China, thus allowing customers to use Radel PPSU in these designs at no charge. Solvay Specialty Polymers is a global leader in the development of sulfone polymer technology, launching Udel (trademarked) polysulfone nearly 45 years ago. In addition, Solvay’s experience as a key materials supplier in the healthcare field spans more than 20 years. The company is a leading manufacturer of high-performance plastics, offering a broad range of materials for healthcare instruments and medical devices. More recently, Solvay has successfully introduced its line of Solviva (trademarked) Biomaterials and offers them for use in a range of implantable devices.