XtraLite™ provides a quantum leap in microcellular injection
molding technology by eliminating the rough surfaces and other irregularities
common to existing microcellular foaming processes. The XtraLite process can be
easily added to existing injection molding machines.
Intellimold with XtraLite™ is a microcellular injection
molding process that can significantly reduce part weight while also yielding
components with a Class-A finish. The XtraLite process works in conjunction with
the Intellimold technology.
Intellimold with XtraLite also improves flow length, pushes out sinks and
eliminates sinks in parts with unconventional cross-sectional areas, and
provides a consistent microcellular structure.
XtraLite employs conventional chemical blowing agents rather
than the supercritical fluids used in machines outfitted by a leading
microcellular foaming supplier. The result is a process that has easier process
control and setup, requires no additional capital investment, requires no
special screws, and has no high pressure gases/cryogenic liquids and couplings
that can pose safety issues.
How does Intellimold with XtraLite work? In simplistic
terms, it is not much different than opening a can of cola. Once the pressure is
released by opening the can, the trapped air bubbles inside the cola rise to the
surface. Within the injection molding process, Intellimold keeps the air bubbles
created by blowing agents under pressure and away from the cavity surface.
Intellimold is able to accomplish this because it utilizes a pressurized mold
cavity and controls the internal melt pressure within the cavity.
The ability to mold parts with a Class A finish has been a
major obstacle to greater proliferation of microcellular foaming. Since XtraLite
forms a skin on the part surface so no gas bubbles appear, it can be used on
parts requiring cosmetic or class-A surfaces. As the mold cavity fills,
Intellimold with XtraLite controls the internal melt pressure and ensures that
the plastic, not microcell or gas bubbles from the blowing agent, reaches the
part surface. The result is a lighter part with a smooth, high-quality finish.
The XtraLite process provides a consistent microcellular
structure.
There are
no limitations on part or injection machine size. The process achieves the same
tight tolerances as the Intellimold system and is not limited by wall thickness
or part geometry. In addition, parts in multi-cavity and family molds can
benefit from XtraLite. As with Intellimold, the XtraLite feature “pushes out”
sink marks.
To demonstrate the benefits of the XtraLite system, the same
400-gram automotive body cladding was molded using conventional injection
molding, a competitive microcellular foaming process, and IntelliMold with
XtraLite. The part using a competing microcellular foaming process achieved a
12% weight reduction compared to conventional injection molding, but its surface
was not smooth or Class-A quality. The same part molded using XtraLite yielded a
15% weight reduction and had a smooth, paintable Class-A surface. Greater weight
reductions can be achieved with parts that have a thicker cross section.