
Trexel’s 3D in-mould labeling (IML) process for packaging applications has aleady won awards for packaging manufacturers since its introduction in 2012. The process enables the appearance of embossed labeling on the package without the associated tooling costs. The “embossed” look comes from ‘3D’ labels applied during processing.
An application using this process, the Paccor/Unilever 500g polypropylene margarine tub with 3D IML, won the DuPont Packaging Silver Award in 2013 as well as the Emerging Technology award in SPI’s International Design Competition at NPE 2012.
The 3D in-mould label is processed with an injection moulded tub made of expanded polypropylene to incorporate selective masking, creating areas without adhesion. The MuCell process controls the introduction of nitrogen into the polymer. Where there is adhesion between the label and the polymer, the nitrogen migrates through both structures. Where there is no adhesion (by design behind the blue lettering), the nitrogen accumulates between the polymer substrate and the label. The process creates bubble patterns or Braille for a multi-sensory experience.
The margarine tub uses 6% less material than previously. Using the MuCell process also permits a 40% reduction in clamping tonnage, and a 15% reduction in cavity pressure, claims Trexel.
For the moulder, the process opens up opportunities to produce embossed containers without extra tooling costs and no extra setup costs for the modifications. On a consumer level, Trexel says that creativity, differentiation and enhanced visibility on the shelf are the key benefits. In addition, the sensory impact on the feel of the packaging is being touted as a key benefit. The technology opens up new avenues in applying Braille to packaging for the benefit of visually impaired consumers.
Trexel claims that the process imposes no impact on recycling classifications. It also is reported to result in more dimensional stability, due to lower stress, and uniform shrinkage, which in turn leads to reduced warpage and fewer mould iterations.
Using the technology, Trexel says, means that companies can design wall thicknesses for function and appearance, instead of flow characteristics.