One of the first label questions I get from startup medical device manufacturers, or existing companies implementing a new line, is whether its best to use laser or thermal transfer for in house printing. The way this normally gets decided is by utilizing what I call the Pioneer Theory. This states that since pioneers stand a risk of getting arrows shot at them, most people want to circle the wagons and do what they were comfortable with at their former place of employment.
Thus if the group of engineers at the new startup or assigned to the new production line is familiar with laser printers and had good luck with them, then there is a 90% chance that’s what they will use at the new company. There are actual properties that can be considered however, beyond the Pioneer Theory, when choosing a print method for a new company or new manufacturing line.
The first thing that needs to be discussed is the stock itself. Due to the properties of toner vs TTR ribbon, laser stock is almost always uncoated with a relatively rough surface while a TTR ribbon works best on a smooth coated stock. This is where marketing input comes into play. Printers match ink to the coated side of the PMS book for coated TTR material and to the uncoated side of the book for the uncoated laser stock. Seems pretty simple but if marketing has approved a beautiful SBS shelf carton with aqueous or UV coating, and insists the the label ‘match the box’ then that label needs to be on coated stock. Take a look at your official, corporate style book approved logo color in both sides of a PMS book. On a densitometer they are identical but to the human eye the reflectivity is completely different and they appear to be different colors. A marketing guru once brilliantly and somewhat condescendingly suggested that we should just match all stock to the coated side of the PMS book and eliminate the issue. Rather than break his nose on the bar, like Gus McCrae did to the smug and self assured bartender in Lonesome Dove (see below), I calmly explained that were it that simple, ink companies would have quit going to the expense and effort of producing the uncoated side of the PMS book sometime shortly after World War 1. Coated laser materials exist but at this point I don’t have any customers who have successfully ran them through the validation and qualification process. And it has been tried on a few occasions.
We have a number of customers at Advanced Web who have gone to laser printing their packaging labels in full color. The 600 dpi color laser is the undisputed way to go for that process. Color TTR printers exist but the quality, reliability, and media expense are all inferior to the laser printer.
Print durability is another story. In general, most of our customers who use laser printers also shrink wrap the outer carton of their device package. This is not necessary and usually not done for TTR printed labels since the anchorage and abrasion resistance of the ribbon is far superior to most toner and will usually pass the transportation testing process. When it comes to equipment, the TTR printers tend to be cheaper, more reliable, and less costly to repair. Most laser printer manufacturers only grudgingly admit that people actually run pressure sensitive label stock through their printers. Problems like stock curl, adhesive ooze, environmental sensitivity, and spotty toner coverage seem to be more common on sheet fed laser stock. Roll stock is a bit more forgiving and problems like ribbon wrinkling or a deep die cut on the roll label stock are a bit simpler to fix. In both cases a well thought out and executed preventative maintenance schedule can avert a lot of issues. With any luck you will not need a house call from Dr O, seen above analyzing some balky laser material in a clean room final pack area (Photo credits to M, Heckley, renowned packaging pro).
Whichever method you are choosing rest assured that both have an extensive track record in labeling terminally sterilized device packaging. Both toner and TTR ribbon survive most of the common sterilization environments and provide that durable package labeling required by our friends at the FDA. In fact for a limited time only, if you send me a stamped, self addressed envelope and two Wheaties box tops, I’ll send you your very own copy of the Code of Federal Regul
ations, CFR 21, Part 820. It even has the almost Tom Clancy/ John Grisham-like excitement filled Part 11, which deals with electronic records and signatures. Actually, if you just send your email and address I’ll mail one of handy, checkbook sized booklets out while supplies (about 35 of em) last. If you act now you will not get a Ginsu knife or Popiel Pocket Fisherman. Since it could be out of date before it was printed, no accuracy guarantees are included.
Also remember MDM Midwest is rapidly approaching in less than a month. Stand by for an update on an exciting educational opportunity on this site in a couple weeks.