How to print with low migration inks: 5 things to take into account

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The demand for food safety, food packaging guidelines, and other standards and legislation require the label printing industry to offer labels that meet ink migration limits as ink contain ingredients that are harmful to our health. Low migration inks might be the answer to this challenge. Many think that when low-migration inks are applied to a substrate, the ink will not migrate to the other side, causing unwanted contamination. However, there’s far more to consider than just loading up the printing press with a low migration ink. It may sound simple, but it is not always easy to keep ink on its side of a package and the food on the other.

The definition of low migrations inks, used by the European Printing Ink Association, is: an ink designed for use on food packaging that is formulated using selected components which should ensure that migration from the resultant printing ink film will be within accepted migration limits.  

As said before, working with low migration inks isn’t as simple as loading up the press with this type of ink. Several things should be taken into account to be sure your labels are within accepted migration limits.

To make sure your labels are compliant with the required standards, you need to frequently check the entire UV system. You have to keep track of how many hours UV lamps have been running, if they are still working properly and if the reflectors are still good.

Can the UV system ensure the quality you need?

You want to prevent contamination of conventional and low migration inks. Both ink types shouldn’t come into contact with each other because it affects the curing process.

To prevent contamination from happening, you should only use one type of ink on a single press and don’t replace ink types during changeovers.

Low migration inks have a different chemical composition compared to conventional inks. Because of this, it reacts quicker to temperature and humidity changes, which could mean that you no longer comply with the migration limits.

If you want to work with low migration inks, you need to meet the recommended temperature and humidity levels.

Although there is a trend to work more energy efficient — and to reduce UV consumption — low migration inks require a higher power of UV curing. Why? Because of the different chemical composition, you need more power to make sure the ink polymerizes and attaches to the material. In other words: to ensure the required quality.

If you run a job using low migration inks, you don’t get the same the same color as when using conventional inks. Low migration inks have a lower density, so it is required to have a higher volume of anilox rolls to meet quality requirements.

In short, to print jobs that require low migration properties, you need to make several adjustments to your printing process to ensure the desired quality and meeting the migration limits.

If you want to further discuss the possibilities of low migration inks - and how it could make your printing process more viable in the long term - please feel free to reach out to one of our specialists. We are happy to help!