Expert's Opinion

Food Packaging and Ink

By Dr. Don P. Duncan, Director of Research, Wikoff Color Corporation | 10.13.10

Food packaging has gotten to be a lot less fun in the last three to four years. After a couple of instances in Europe where local, sub-optimal ink formulations were used and ink components were found to have migrated into food consumed by children, an intense focus in Europe and North America was applied to all aspects of food packaging. There are some, including myself, who contend that these particular problems were 100% avoidable, but now that the “industry” had proven that it can contaminate children’s food, the regulators and the public want to eliminate this potential for error by regulation.

Some large consumer packaged goods (CPG) companies have issued extensive lists of chemicals that are permitted and forbidden in print for any of their work, regardless of the type of work. Chemicals that are forbidden are pretty simple to handle, as an ink formulator. These are things that shouldn’t be used in food packaging anyway. This type of list is called a “negative” list.

The other type of list, a “positive” list, limits ink formulation only to those items on the list. This is a very conservative approach, which seems to result from significant pain incurred by CPGs as a result of the contamination issues. However, it is very limiting for all, as it prohibits the use of any new or potentially better raw materials without express approval.

This is a difficult time. The CPGs got burned, some badly, because of food contamination issues. The reaction to this problem has been to micromanage ink formulation as a defensive strategy. This likely will be found to be, at some point, an over-reaction as it limits the improvement options (performance and cost) of printing inks. We’ll all have to work through this over time.

A large percentage of food packaging print is for secondary packaging. This means that the food is sealed in some type of interior container which is itself placed in the printed container. This has been a growing trend, especially in frozen foods, and greatly reduces the risk for any food contamination from ink. For other foods, such as ice cream, juices and some dairy products, the print is on the outside of primary packaging, with the food product in contact with the non-print side of the package. In these cases, significant care must be taken to make sure that the ink is properly formulated, that the printing is done properly, that the inks and coatings are fully dried/cured, and that no other materials (fountain solution, press wash etc.) contaminate the inside of the package. It takes a team approach, including the ink maker, the substrate manufacturer, the printer and the print buyer. This is a stable process that has resulted in safe and attractive food packaging for many years, but it must be done correctly all the way through.

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