support-free 3d printing with »twocure«...users of resin-based 3d printing know that support...
TRANSCRIPT
1 TwoCURE system: cooled process chamber
with dosing unit and high-resolution UV projection
(50μm,2580x1650pixels).
2 »Freeing« the components by melting
the frozen block in the TwoCURE process.
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Fraunhofer Institute for Laser Technology ILT, www.ilt.fraunhofer.de
DQS certified by DIN EN ISO 9001, Reg.-No.: DE-69572-01
Result
The light unit (UV) projects the geometry of the object onto
the (still) liquid resin layer, which cures at the exposed areas.
Due to the cooled environment (installation walls, process
space and platform), the surrounding resin areas are solidified
instantly by »freezing«.
In this way, the hardened structures can »float« free of
supports in the entire 3D construction space. The curing of the
component is done chemically by light and the solidification
of the surrounding material thermally by cold. The name
»TwoCure« reflects these two types of hardening. Since
completely frozen block is created in each cycle, they can be
ejected from the machine and then a new print job started,
greatly simplifying process automation. The component is thus
»freed« in the last step when the frozen block is melted.
Application
The TwoCure technology can be of great advantage for all
companies that produce individual plastic parts in large quan-
tities or small batches. In the future, a TwoCure system will
be able to manufacture – daily – several hundred individual
otoplastics for hearing aids, molds for jewelry production or
plastic components in small series automatically.
Contact
Dipl.-Chem. Holger Leonards
Telephone +49 241 8906-601
Dr. Martin Wehner
Telephone +49 241 8906-202
Task
Users of resin-based 3D printing know that support structures
are both cumbersome but also necessary. On the one hand,
these structures require CAD preparation and, on the other,
they have to be removed after printing. Owing to this, they
require additional process steps, cause avoidable waste and
also worsen the surface quality. So far, however, such support
structures are essential because the often filigree plastic com-
ponents must be supported and connected to the platform.
Approach
Similar to stereolithography, the »TwoCure« process uses
photolithographic exposure, which causes the liquid resins to
cure layer by layer. Added to this is another property of the
process, the cooling of the materials below their glass transition
or melting point. This additional phase transition was made
possible by materials specially developed for this process and
its adaptation.
SUPPORT-FREE 3D PRINTING WITH »TwoCURE«
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