1979–2004: Milestones in Medical Device Packaging

Originally Published MDDI August 2004

Packaging  



The past 25 years have been revolutionary for medical packaging, but it just may be that the best is yet to come.

Carl D. Marotta

Sometimes, synergy emerges in the most unexpected places and circumstances. Such a marriage—whether in science, industry, or art—usually results in significant advances in the state of the art. In the 1970s, a need for high-performance packaging, driven by a rapidly growing device market, presented the right conditions for just such synergy. Device manufacturers needed functional packaging for their sterile disposable (single-use) devices. They found themselves on a hunt for a product that did not widely exist—a package that could be sealed, sterilized, packed, and shipped, and then stored and opened easily and cleanly at the point of use.

A Little History

The state of the art in medical packaging prior to the early 1970s consisted primarily of film and paper bags, pouches, or boxes enclosed in an overwrap designed to protect the sterility of the package's contents. Traditional sterilization processes, such as steam or dry heat, were suited for only a few materials, such as vinyl-coated papers.

At the time, devices that required environmental barriers were packaged in aluminum-foil pouches, bottles, glass vials, or injection-molded barrier plastics. All of the available methods and materials fell short of the characteristics required for packaging sterile disposable devices. And, the term clean peelability was not in wide use. In some cases, an acceptable clean peel was determined by simply separating the top layer of a paper package and rating the degree of fiber tear.

The porosity was measured in Gurley seconds, and values of several hundred seconds were commonly deemed acceptable. However, with this porosity, a penalty was paid in the form of slow ethylene oxide (EtO) sterilization cycles. Packaging adhesives were limited, and those available gave manufacturers little control over the sealing process. The adhesives also were not user-friendly, and thus they were not high on customer satisfaction lists.

The Quest for Sterile Packaging

So, the search was on for tray lidding and pouch materials that would meet a growing list of exacting performance characteristics for sterile medical device packaging. Coincidentally, the key material that ultimately filled the bill was being introduced to market at the same time. DuPont's medical-grade Tyvek redefined packaging for the late 1970s. Not long after, Canon Communications launched MD&DI, and I began to write a column called “Packaging Forum.”

With the convergence of these events, a market hungry for a high-performance sterile packaging was satisfied. This synergy made medical-grade Tyvek the most important packaging material used in the healthcare industry then, now, and for the foreseeable future. The combined contributions of DuPont, packaging converters, coaters, and printers revolutionized medical device packaging in the 1980s. The sidebar, “The Role of Heat-Seal Coating in Seal-Peel Medical Packaging,” provides the functional and process criteria that illustrate how combinations of substrate, coatings, and process parameters work together.
 
The 1980s and 1990s were noted for the rapid growth of medical device packaging and the growth of the key players in this market. Maintaining its leadership position worldwide for its strategically important material, DuPont continued to lead the market by working closely with major medical device manufacturers and packaging converters. The market for sterile device packaging expanded, particularly in the development of film-based pouch and form-fill-seal (FFS) packaging. 

During these decades, heat-seal coatings were developed for specific applications. Other significant materials-related developments include:

•Sealant films (with uncoated Tyvek). This combination provides a cost-effective solution for pouches and FFS forming webs.
•Specialty coatings. These coatings are ideal for high-performance applications where quality is critical and the ability to seal to semirigid trays is essential.
•High-temperature coatings. These coatings are suitable for dry-heat sterilization and autoclaving.
•High-altitude lidding. This lidding can withstand the internal pressures generated at high altitudes.
•Water-repellent aqueous coatings. Rather than providing a moisture barrier, these coatings repel water.
•Zoned-coating lidstock. This lidstock is designed for die-cut or FFS packaging.
•Autoclavable packaging. Both lidding and pouches can now withstand the autoclaving process.

Trends in the 2000s 

The future for sterile device packaging holds both challenges and opportunities. First and foremost, packagers must listen to customer requests. Just when we think every material has been invented, a customer will require performance just beyond what's available.

Of the hundreds of inquiries received annually, each should be treated as important. Most requests can be resolved easily with currently available materials. It is the exceptional request that may point to future needs and could lead to the next packaging breakthrough. Packagers and package developers must focus on four primary areas:

•Functionality. Products of the future should enable customers to evaluate a range of coatings in terms of seal strength and other characteristics for an ideal solution.
•Lean manufacturing. With the increased adoption of six-sigma and other lean manufacturing methods, packagers should be able to eliminate waste and maximize efficiencies across their operations.
•Costs. It is unclear whether the industry can deliver packaging that is more cost-effective. It will be essential for packagers to look at alternative ingredient sources as well as source reduction.
•Prevalidated materials. Products are needed that will reduce sterilizer cycle time and provide higher temperature resistance. Ultimately, customers will demand higher quality at a lower cost.

The next decade will require improved materials that provide more functionality and more flexibility. They will need to meet international standards. Key advancements will likely include:

•Zone-applied coatings that virtually eliminate coating and product contact.
•Product lines that are fully ISO 2002 and ISO 11607 compliant.
•More designed structures, possibly all films or film-foil combinations.
•Multilayer thermoformable plastics.
•More grades of Tyvek with functional distinctions.
•Multifunctional pouches that offer removable sterilization vents with a wide assortment of layers.
•On-line printable, bar-coded film pouches in roll form. 
•Hybrid applications that combine device and drug packaging features.

It's not out of the question to see the development of a package based on nanotechnology, the science of ultrathin surfaces. Some large companies have identified nanotechnology as a key focus area. We all can dream about it, knowing that someone is giving it serious thought.   

Copyright ©2004 Medical Device & Diagnostic Industry