Medtech manufacturers are using advanced silicone processing techniques to enhance device performance, assembly and visibility.
By Matt Pagel, Lubrizol
In part one of this series, we discussed silicone’s reputation as a versatile, biocompatible material that meets tough demands in medical device design. Part two dives deeper into its remarkable potential, where the dynamic pairing of vulcanized and unvulcanized sheeting takes its versatility even further, including enhanced customization with pigments, radiopaque additives, and medical-grade inks.
Hands-on visual inspections complement automated quality systems to ensure silicone materials perform with reliability in every layer. [Photo courtesy of Lubrizol]
It’s all part of how today’s silicone-based solutions are enabling better performance, efficiency and patient outcomes.
Vulcanized or unvulcanized?
Medical-grade silicone sheeting is an incredibly versatile material used in wound dressings, implants and other medical devices. This particular sheet is vulcanized, meaning it’s already cured for strength and stability. [Photo courtesy of Lubrizol]
As many bakers know, silicone sheets and parchment paper coated with silicone are often used to prevent sticking. Because cured silicone has low surface energy, this makes it difficult for other materials to adhere to it. Fortunately, for the purpose of device fabrication, unvulcanized silicone sheeting can be vulcanized to form a strong bond with already vulcanized silicone components.
Unvulcanized sheeting is soft and tacky until heat is applied to cure it. Once heated, it acts like doubled-sided tape — perfect for bonding vulcanized sheets or attaching components, giving manufacturers a clean, consistent assembly process without the hassle of liquid adhesives. It’s cut to the exact shape you need, placed where adhesion is required, and then heat-cured to create a precise bond.
Carefully controlled manufacturing practices are required to form unvulcanized silicone into sheeting without contamination or flaw. Even the smallest contaminant or wrinkle can compromise a product destined for use in wound care, implants or other life-critical devices. Machines do heavy lifting, but the final stage of calendering is all about the human touch. Here, technicians team up to make sure each sheet is perfect before it moves on. [Photo courtesy of Lubrizol]
Taking silicone’s flexibility a step further, laminated sheeting combines vulcanized and unvulcanized silicone in a single material. Imagine a single-sided tape, with the vulcanized layer adding strength and the unvulcanized side creating adhesion. This type of sheeting may be used to seal or patch a dip cast balloon or shell or to encapsulate a metal component (e.g., a circuit) to protect it from the body while simultaneously protecting the body from whatever has been encapsulated.
Silicone is great on its own, but with a few smart enhancements, customized silicone becomes an even better fit for all kinds of devices. With the right additives, it can do even more to enhance product perceptibility and identification.
Pigments and color matching
This pigmented silicone sheeting, mid-process, has a vibrant blue hue that helps clinicians quickly distinguish devices by size, function or placement. [Photo courtesy of Lubrizol]
Standardized color schemes further allow medical device manufacturers to create a recognizable product line while ensuring compliance with industry safety and identification rules.
Importantly, these pigments do not alter the material. The only thing that changes with pigment is the color. Silicone’s toughness, flexibility and body-friendly properties stay the same.
Additives for imaging
Silicone is naturally invisible under imaging techniques, but radiopaque additives make it easy to track and monitor inside the body. For devices that require precise placement and regular check-ups, these agents make silicone clearly visible on X-rays and scans.
Surgeons and medical teams rely on this capability to get a clear view whether they’re placing an implant, guiding a catheter or using a surgical tool. For implantable drug systems and neurological electrodes, adding radiopacity ensures that providers can monitor placement and fine-tune positioning over time. Devices like hydrocephalus shunts and implantable infusion pumps also benefit from radiopacity, allowing for easy X-ray visibility and periodic monitoring without invasive inspections.
Inks and markings
Specialized inks let medical-grade silicone hold onto permanent, high-contrast markings, so they’ll stay readable for years, whether it’s for function, branding or instructions.
Think about printed measurement scales that guide insertion depth in catheter systems, or wearable medical devices like continuous glucose monitors and ECG electrodes that may feature instructions or alignment indicators. These markings play multiple critical roles in many devices. Inks must also be formulated to withstand fading or degrading, especially where there is prolonged bodily contact, without releasing harmful substances or causing irritation.
Silicone’s versatility in medical applications isn’t just about the material itself. It’s also about how it’s processed and put together. The mix of vulcanized and unvulcanized silicone streamlines manufacturing without sacrificing durability. Add pigments, radiopaque agents and medical-grade inks, and the customization potential is huge.
Designing with silicone? Whether you need it to be stronger, softer or more visible, a medical materials specialist can help you get it just right.
Matt Pagel [Photo courtesy of Lubrizol]
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The opinions expressed in this blog post are the author’s only and do not necessarily reflect those of Medical Design & Outsourcing or its employees.
