Injection molding: IML gets the royal treatment

On the day we spoke with Belgian in-mold label supplier Verstraete, the company was hosting a visit from the nation's king. Heads of state and royalty typically only visit companies in good health, and that's indeed the case at Verstraete as the company is celebrating development of a number of new IML options, including in-mold labels with metallic finish, ones for thermoforming and labels able to provide gas or light barrier performance.

One of the recent innovations is the development of metallic in-mold labels, said Nico Van de Walle, product innovation manager at the company. Verstraete introduced these last year and is seeing growing interest in them, but continues working to spread word of these to brand owners, he explained. Metallic IM labels are made using cold foil adhesion. A thin layer of metal is added to the plastic film wherever it is needed.

"You cannot get the same affects with a metallic ink that you get with metallic IML," said Van de Walle. Metallic IMLs are aimed at brand owners, he explained, as it can help them jumpstart a metal-to-plastics conversion. Paint cans are just one application he believes could benefit from these labels.

Van de Walle also discussed IML for thermoformed packaging with PlasticsToday. "Everyone seems ready to really introduce it now," he noted. "Now we just need some pioneering customers," and said those are at the ready. (We've reportedly extensively on this subject; here you can read recent articles on IML for thermoforming here, including on the first thermoformed and IMLd packaging made in the U.S. and an interview with a Kraft Foods' packaging specialist on his company's interest in it.) As Van de Walle noted, "We see thermoforming's ability to form barrier packaging as a huge one for thermoforming...with IML you can offer that plus a high-end label."

Limitations remain in that to now only polypropylene-compatible IM labels are available for thermoforming, even as amorphous PET and polystyrene still account for major shares of the thermoformed packaging market. The labels available so far also only have an "orange peel" look. Development continues though, said Van de Walle, and he predicts his company's IM labels for thermoforming will be used on commercial applications by year's end.

Not just a pretty face as in-mold labels add functional performance 

Very new from Verstraete are IM labels that offer not just appearance but also function. This can include, for example, light or oxygen barriers. The company has produced two types of labels suitable for creating an oxygen barrier, one offering a moderate barrier and the second a very high level of barrier performance, said Van de Walle.

Testing done by Verstraete with one of its customers has shown that the moderate barrier IM labels can contribute to an oxygen transmission rate (OTR) as low as 0.009cc/tray/day, with that testing done at 32°C in 50% relative humidity. "This is comparable to the OTR of standard PP/EVOH/PP thermoformed containers," he noted, with the difference that an IM label with barrier performance can potentially be much thinner, promoting material savings. "We're ready for industrial testing of these" labels, he said. 

Also in development are labels that come equipped with a light barrier. These labels are printed on a film that offers more than 99% opacity, he said, and there is less than 1% of ultraviolet light transmission across the entire UV range. The film used is grayish on the backside, with the challenge to keep the outer side of the label white. Applications could include dairy products and more.

Verstraete's labels will be on display at next month's Interpack show in Düsseldorf, Germany. The company has foregone having its own booth and instead is supplying labels to a number of other exhibitors who will promote these labels on their own packaging.