Trexel Inc. recently made its global introduction of its MuCell 3D in-mold labeling (IML) process for packaging applications. Brent Strawbridge, vice president of sales, presented this unique, award-winning label at the recent IMLCON in Phoenix. The MuCell process creates a 3D label with the look of embossed labeling on the package without any need for additional tooling costs.
Strawbridge pointed out in his presentation that when the MuCell process was first commercialized, more than two decades ago, the technology was used to reduce weight by reducing the density of the molded component. The wall sections of components such as those used in consumer electronics and automotive parts, tended to be thicker, thus offering good opportunities for weight reduction using MuCell.
Over the past few years, the MuCell Microcellular foaming technology has been used in some very unique applications, and the IML 3D label certainly fits that bill. The 3D in-mold label was originally developed for the Paccor/Unilever 500g polypropylene margarine tub. It won the DuPont Silver Award in 2013 as well as the Emerging Technology award in SPI's International Design Competition at NPE2012.
Now that the exclusive agreement that Trexel had with Unilever has expired, the company is free to offer this technology to other brand owners, who want to differentiate their products by its unique visual appearance and soft touch effect to packages. In addition to offering a special look and feel to packaging, the 3D IML offers a 10% improvement in thermal insulation.
The 3D IML is processes with an injection-molded 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 for a multi-sensory experience. This also provides the possibility to do Braille for the visually impaired.
Because the process uses a low-pressure system, a 40% reduction in clamp tonnage can be achieved, and a 15% cavity pressure reduction. Additionally the process allows molders the possibility to propose embossed containers without extra tooling costs and there are no extra set-up costs for the embossing modifications.