Retirement is indeed a wonderful thing. Although I’m not quite 100% retired, as I’m still consulting up a storm for the AWT mothership a solid 2 or 3 days a month through the end of 2017, most of the time I can sleep in, have a beer or two for lunch, and forget which day of the week it is. A fine lifestyle that I’ve looked forward to for decades.
The label industry still lurches on however. With UDI requiring a label with specific and traceable data on it, almost everything in the medical device realm requires a label. Affixed and legible is still the Holy Grail for packaging labels, a requirement that is often as difficult to pin down as the Holy Grail. On the other hand, hard goods labels (permanent labels on things like controllers, programmers, and other electronic devices that complement the disposables), have very specific requirements which are normally spelled out by quasi-governmental agencies like Underwriters Laboratories. Back in November of 2009 when retirement was just an elusive dream for me, I wrote a blog post on the UL Mystery. Even with the implementation of UDI, much of the information still applies.
Historically, hard goods labels have been the domain of silk screeners. They would typically reverse print the graphics on a nice thick piece of polycarbonate (Lexan, if you are one of those people who tell me to make a Xerox, FedEx that package, or blow their nose with a Kleenex), then apply a layer of thick transfer adhesive to the back, and then die-cut it. This is very durable and works well.
With the UDI requirements, normally a discrete barcode needs to be generated. The most efficient way to do this is to normally thermal transfer printing on the label, which does not work worth a damn on textured polycarbonate. Also, polycarb is typically an indoor film.
Not that a lot of devices get programmed or controlled on a picnic table, but the durability in both temperature and environmental resistance is an attractive feature of polyester, PET…..or Mylar if you are a FedEx / Xerox person. We normally use a base of clear, white, or silver PET, print your graphics and static information on it, and then laminate it with a thermal transfer receptive PET overlaminate. It can then be printed with one of the high end resin ribbons, many of which have Automotive Industry Action Group (AIAG) approval for under hood applications. High heat, gasoline, oil, brake fluid, and antifreeze are typically much nastier than the isopropyl alcohol, cidex, or hydrogen peroxide cleaning compounds used at ambient temperature in a hospital or clinical setting.
The beauty of the system is that everything including the label stock, adhesive, inks, laminates, ribbon, and even the printer in some cases, have been tested and qualified by UL. Per my ‘09 article, we produce the entire structure, send it along with test panels of the materials that we want the label system qualified on, and a wheelbarrow full of cash to UL labs in Northbrook, IL. They then send us back the system qualification with approved surfaces, temperature ranges, and indoor and/or indoor-outdoor approval. For those in the regulatory field of medical device companies, this gives the packaging engineer a tested-and-proven set of documentation to pass on to the reg affairs folks and cuts down their testing to a much more manageable level.
Not surprisingly, the team has printed up samples of a number of constructions which can be yours for the low, low price of free! Just give Blake Insteness a holler and he will drop some in the mail for you to play with. All we need to know is the surface the label sticks to, operating temperature, and what type of final look you want for the label.
For the surface, keep in mind that it isn’t aluminum if it’s painted. It is whatever paint system is used, something that UL also tests for. Texture is another really good thing to know. The more texture, the more adhesive coat weight is needed to ooze into the valleys to form a solid bond. A number of our device customers have successfully implemented one or more of our UL systems, and we do have a polycarbonate option if you or your marketeers are in love with the ‘velvet Lexan look’.
Good luck. If you need me I will be somewhere on Lake Superior.