MuCell Microcellular Foaming technology from Trexel Inc. cuts finished part weights up to 10% in a prototype thin-walled container being developed for a European margarine producer.

MuCell Microcellular Foaming technology from Trexel Inc. cuts finished part weights up to 10% in a prototype thin-walled container being developed for a European margarine producer.


Ultrathin in-mold labeling coupled with a recent thin wall packaging process is poised to "turn thin-wall packaging on its head," says Autobar Packaging Group in France. The company calls the technology SLIM (Super Light Injection Molding). According to Eric Chavent, group commercial director for SLIM, the use of MuCell Microcellular Foaming technology from Trexel Inc., Woburn Mass., cuts finished part weights up to 10% in thin-wall packages. It also lets packaging producers use smaller machines, improve production throughput, and lets designers incorporate in-mold labeling. Parts molded using SLIM will also have good insulating properties thanks to the inherently low thermal conductivity of MuCell microcellular foam.

According to Autobar, SLIM is an alternative technology to injection molding/in-mold labeling. Recent tests on a prototype 0.50-kg margarine tub had 50% faster throughput and shaved 6% off each container's weight. It also let the machine run with less pressure and clamp tonnage than necessary for traditional injection molding.

"We see a tremendous number of benefits with the SLIM program using the MuCell process," says Chavent. Autobar has developed a 12-cavity mold for the margarine tub and says cost savings add up quickly. A 6 to 7% weight saving means little for an individual margarine tub, for example, but can be significant when container numbers reach a planned 200,000,000/yr. On top of that, says Chavent, "we can avoid a German environmental tax on weight. We are also able to make this application work on smaller machines, which in the tub application saves $8 million dollars otherwise needed for new machines."

Trexel Inc., (781) 932-0202, trexel.com