Original procedure developed by
Nicholas Fang and adapted by Joseph Muskin, Matthew Ragusa, Kungway Chang,
and Ian McInerny from the Center for Nanoscale Chemical-Electrical-Mechanical
Manufacturing Systems, University of Illinois, Urbana-Champaign. See "Three-Dimensional Printing Using a Photoinitiated Polymer," J. Chem. Educ., 2010, 87 (5), pp 512–514.
In this lithography experiment light creates free
radicals from phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide which induce
polymerization of 1,6-hexanediol diacrylate. Light is supplied by a computer
projector which shines the pattern for one layer at a time. After each layer,
the elevator is slightly lowered and the process is repeated. A dye (Sudan
I) is included to prevent light from penentrating much below the surface of
This experiment uses a computer with powerpoint and connected to
a video projector, a magnifying glass, mirror, and a platform elevator.
Adjust the focus so maximum sharpness occurs at the elevator platform.
Fill the beaker with monomer solution to just above the level of
Red light is used for alignment but does not cause polymerization.
For each level, shine white light in the desired pattern. Avoid long
exposures that produce too much heat. Darken the screen whenever the
stage is advanced.
Continue. This movie plays 4x real time.
Recover solution then rinse with water.
Use a razor blade to remove pieces.
Small chess pieces are produced from the used pattern.