A new technology for producing rapid prototypes was one of
the highlights of Rapid 2009, held May 12-14 in Schaumburg, IL.
Huntsman Advanced Materials introduced Araldite Digitalis,
which is based on new micro-electro mechanical system technology to create
three-dimensional objects from photo-curable polymers. The big improvement of
the new approach over laser-based stereolithography systems is speed. The head
speed of Digitalis is 0.12 to 1.97 inches per second.
"Araldite Digitalis opens the way to a greater range of
possible applications and a new era in rapid manufacturing," says Philippe
Michaud, global technology director of Huntsman
Advanced Materials. "It significantly reduces production times and thereby
There are a few limitations, however. One is system cost.
The Digitalis is only offered commercially now in Europe, but the U.S. equivalent
cost is around $500,000. Another is lack of materials. Only one material grade
is currently available for the new machine. "Araldite Digitalis will grow with
customers," says Michaud.
At the heart of Araldite Digitalis is an MLS
MicroLightSwitch, a new exposure system that runs via a computer-controlled
micro-mechanical shutter system. A large surface area of radiation curable
resin is selectively exposed in a single step.
Lasers, such as those used in stereolithography, expose one point at a
time. In the Huntsman system, light from UV lamps is distributed through fiber
optics onto an exposure bar where there are MLS units distributing UV light
pixels to the resin surface.
The computer-controlled shutter mechanisms steer the
exposure of the UV light to avoid scattering. The illuminating angle is 90
degrees, allowing uniform accuracy. Micro lenses refocus the UV light after
leaving the MLS.