MuCell microcellular molding has been around for more than a decade, but it's just now beginning to catch on in a big way. There are several reasons for this. First, Trexel Inc., the company that developed and marketed the technology no longer charges a large licensing fee to use the technology. Secondly, the company has invested heavily in its processing development capabilities and staff, enabling the commercialization of applications, which would not have been possible a few years ago.
Lastly, notes Brent Strawbridge, vice president of sales for North America for Trexel, the company began marketing the technology differently. Instead of marketing MuCell microcellular technology solely to molders and moldmakers, the company began marketing heavily to OEMs. If the first group were "reluctant adopters" of the technology, the OEMs have embraced it - particularly the automotive industry where weight reduction is critical to their product.
Ford takes MuCell for a spin
Trexel and Proper Mold & Engineering, a mold manufacturer and molder primarily for the automotive industry, were partners with Ford Motor Co. on the development of its MuCell instrument panel for the 2012 Escape and Kuga (read more here and here). Ford is starting to design various components for MuCell and also requiring its suppliers to buy some 50 MuCell-capable machines.
"Essentially," said Steve Braig, President & CEO of Trexel, "Ford is after the weight savings. They can get a weight reduction of between 8-10% right now with mostly existing designs. The rest of the savings they can achieve, approximately 20-25%, will come from designing for MuCell."
Braig, who was president of injection molding machinery and automation supplier Engel prior to taking the position of president of Trexel, noted that his former company has always endorsed the MuCell process. At NPE 2009, Trexel didn't have a booth, but had a mold running an automotive part using MuCell in Engel's booth. "We met with some people who saw the possibilities of the process, believed in it and soon after Trexel started working with Ford," Braig explained.
"Over the years we've developed a lot of automotive applications including some relatively straight-forward fan covers. The instrument panel structure [that received the award from the SPE] is a very complex part, and in addition to being complex from a dimensional standpoint this IP retainer also needs to satisfy a head impact crash test and all the other safety standards a cockpit needs to satisfy," Braig added. I think the reason why Ford won the overall award - although Mucell has been around for a long time - is that this was a profound development. The Ford IP project took approximately 18 months to develop. It was an excellent partnership with Ford as well as an excellent example of collaboration between the OEM and the tooling supplier."
Beyond the light weight, other benefits include much greater dimensional stability than a non-MuCell part, which has helped particularly the automotive industry to select a lower cost material. "Years ago, most of these instrument panel structures were engineering thermoplastics, so obviously a shift in the industry to a commodity like PP and filled PP has been a huge benefit," said Braig. "This instrument panel has such complexity that with straight injection molded PP the warpage would be so profound that you'd go through some serious mold iterations to get a straight part. We don't have those problems with MuCell."
Winning over the naysayers
Braig acknowledged that the road of adoption of the MuCell molding process has been long, but he's pragmatic about it. "Whenever you introduce something new you get naysayers - people who like to play it safe. It was no different with Ford, but we had the chief engineer for cockpits and interiors at Ford who wouldn't take no for an answer," Braig said. "He was so convinced in the process and in the mass reduction and cost savings, he became a champion of MuCell."
The MuCell microcellular foam process has been around for a long time. The original patents at MIT started in late 1980s and continued into the early 1990s, with most of the original research intended for extrusion apps. In 1995, Trexel was formed and actually focused on extrusion applications. "The first few years we worked on commercializing the process," noted Braig. "It's one thing to get a patented invention and quite another to make a robust and repeatable process. At some point along the way, Trexel realized that injection molding had greater opportunities for applications than extrusion. In the late 1990s and early 2000s, Trexel got serious about MuCell for injection molding applications."
MuCell has evolved over the past decade, as has Trexel's business strategy, which has worked hand-in-hand to make the process more acceptable to more companies. "We had no direct competitors, but it was a strategic mistake in that we sold the hardware but then the customers had to buy an annual license and pay royalty fees based on the amount of material involved," Braig acknowledged. "We've eliminated all of those fees and today it's a straight capital equipment purchase for customers but also comes with the rights to practice the technology under our patents."
Braig noted that in addition to the strategic business change, over the last 10 years Trexel has developed both the process and the technology that has brought MuCell into the mainstream. "Even over the last five years several material manufacturers have seen the value in this process and adjusted their material formulations to have better flow characteristics to give us better surface quality," Braig said. Materials such as Nylon 6 and 6/6 have become more MuCell friendly, and we have a friendlier MuCell polyamide to get an excellent surface quality."
Ultimately, said Braig, "We fought the good fight and came out winner."