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Labels
He continues: “The sensors in the nitrogen chamber of the Truepress Jet L350UV+LM dictate that the press will not run if oxygen is present. This guarantees that low migration printing is actually delivered at all times. Optional chill rollers then expand the versatility and flexibility of material types that can be supported
to include thin and heat-sensitive films. Together they help to extend the benefits of digital technologies for variable and short-run printing to a larger range of food packaging applications.”
Despite the need for a whole-process workflow approach, the UV ink formulations do play a major role. The individual components will impact the
final composition, with different digital
ink types featuring different molecular structures. The low viscosity and small molecular structure of UV inkjet inks makes it challenging to achieve a proper cure once they penetrate the substrate.
This is where Screen’s proprietary low migration ink technology comes into play – they are specially developed with a unique material composition to work with the nitrogen purge mechanism and accelerate
and deepen UV curing. Together, they are highly successful in reducing the migration
of ink components and the risk of tainting foodstuffs. Where there is a known functional barrier, such as glass or plastic, products can be labelled using regular inkjet UV inks.
Other factors involved in assessing ink migration include: temperature, contact time, surface-to-volume ratio, type of foodstuff, substrate material composition, properties of the potential migrating materials and type of contact – loose or tight; barrier or no barrier. Testing can take several days and must take all these factors into account.
Screen has established links with test laboratories, such as Triskelion and Swiss Quality Testing Services (SQTS), regarding its LM ink portfolio. A customer can seek advice from such independent migration testing laboratories based on
Legislation
The regulatory landscape that printers
and converters must work within grows ever-more complex. EuPIA (the European Printing Ink Association) has a number
of regulations in place related to food packaging, such as its enhanced Good Manufacturing Practices (GMP) guidelines that cover the manufacture of all varnishes and coatings as well as inks designed to be printed on to food contact materials.
Permissible migration is very low, with less than 10 parts per billion (ppb) widely regarded as having no effect but even at this level or below, there must be no material detectable with potential carcinogenic activity.
In Australia and New Zealand, Food Standards ANZ (FSANZ) governs what is permissible regarding migration of chemicals into foodstuffs and has an established Code that, in short, states:
“The Code mandates that food packaging must be safe. Specifically, Standard 1.1.1-10 (11) of the Code states that any ‘packaging’ and any ‘article or material in the packaging or in contact with the food’ must not be capable of being swallowed or obstructing any alimentary or respiratory passage, or otherwise cause bodily harm, distress, or discomfort, if taken into the mouth.”
This standard also explains that “article or material” includes materials in contact with food, including packaging, but also other materials such as moisture absorbers, mould inhibitors, oxygen absorbers,
promotional materials, and writing or graphics in or on the package.”
In the US, FDA regulates the materials that can be used in items (packaging) that will come into contact with food. There is a basic assumption that any materials used in food contact applications will become part of the food unless documented testing proves otherwise.
Inks and coatings that do not have direct food contact are not regulated so long as there is a functional barrier between the food contact side and the ink or coating, and the inks and coatings do not migrate to the food contact side during various steps in the process.
Swiss legislation demands that all ink
raw materials for food packaging have to be listed and comply with specific migration limits (SMLs). Japan’s Food Sanitation Law sets out that contamination of foodstuffs by their packaging must be avoided.
“Admittedly, it’s a complicated area,” Scott says. “And the final responsibility lies with the packaging company’s processes and integrated supply chain, but it’s fair to say that Screen has longer experience in UV digital ink migration issues than any other manufacturer.”
With Screen’s low migration products, converters have access to the tools they need to enter new markets and take on a broader range of label and packaging jobs in the knowledge that they are best placed to achieve food packaging compliance. 21
Portuguese printer adds LM to its Screen stable
One of the latest installations of a Screen Truepress Jet L350UV-LM low-migration ink label press is at Portugal’s Astrografe, which has been using a non-LM Screen press for five years.
Marco Cardoso, manager of Astrografe says, “We replaced our first Screen inkjet system with the newest, innovative L350UV+LM to meet our customers’ demand for specialised labels, such
as certified low migration food labels
for the organic food industry. Since installation, we have found that this new
system has helped us open new markets, and even win new customers while other companies are struggling to survive.
“During these challenging times, it is even more important for customers to be flexible and run short print runs to adjust to fast-changing circumstances. And this is exactly what the L350UV+LM system allows us to do,” he says.
Established in 1980, Astrografe has built a strong position in niche areas of label printing, such as the Portuguese organic food industry and the ink sector.
The family-owned business, in Loures,
just north of Lisbon, is known for being able
to provide services other companies cannot deliver.
Installed by Astrografe: Screen Truepress Jet L350UV+LM
this information.
Main
Protection: Some packaging formats already have a functional barrier, while others need low-migration ink systems
Left
New: Screen’s new L350UV-SAI series will feature a low- migration model
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