MULTI-MATERIAL SEPARATION LAYERS FOR ADDITIVE FABRICATION
According to some aspects, a laminated multi-material separation layer is provided for use in an additive fabrication device wherein layers of solid material are formed in contact with the separation layer by curing a liquid photopolymer. In some embodiments, the laminated multi-material layer may include an elastic first layer that aids in separation of cured photopolymer from the container in addition to a barrier layer on an upper surface that protects the first layer from exposure to substances in the liquid photopolymer that may not be compatible with the material of the first layer.
1 . An additive fabrication device configured to fabricate parts by curing a liquid photopolymer to form layers of cured photopolymer, the additive fabrication device comprising:
an open-topped vessel configured to hold the liquid photopolymer and comprising a laminated multi-material layer configured to facilitate separation of cured photopolymer from an exposed surface of the laminated multi-material layer, the laminated multi-material layer comprising:
a first material layer; and
a barrier layer bonded to at least a portion of the first material layer, the barrier layer having an oxygen permeability of at least 10 Barrer and forming the exposed surface of the container; and
at least one energy source configured to direct actinic radiation through the laminated multi-material layer and to cure the liquid photopolymer held by the vessel.
2 . The additive fabrication device of claim 1 , wherein the laminated multi-material layer is bonded to an interior bottom surface of the vessel.
3 . The additive fabrication device of claim 1 , wherein the laminated multi-material layer is suspended between at least two supports.
4 . The additive fabrication device of claim 3 , further comprising at least one roller configured to contact portions of the laminated multi-material layer.
5 . The additive fabrication device of claim 1 , wherein the barrier layer comprises polymethylpentene (PMP).
6 . The additive fabrication device of claim 1 , wherein the barrier layer has a higher selectivity for oxygen than for any compound of the liquid photopolymer.
7 . The additive fabrication device of claim 1 , wherein the first material layer comprises polydimethylsiloxane (PDMS).
8 . The additive fabrication device of claim 1 , wherein the first material layer has an oxygen permeability of at least 200 Barrer.
9 . The additive fabrication device of claim 1 , wherein the second material layer has an oxygen permeability between 20 Barrer and 50 Barrer.
10 . The additive fabrication device of claim 1 , further comprising a second material layer, the second material layer arranged between the first material layer and the barrier layer.
11 . The additive fabrication device of claim 1 , wherein the first material layer is bonded to the barrier layer with a pressure-sensitive adhesive.
12 . The additive fabrication device of claim 1 , wherein the barrier layer has a thickness between 1 mm and 10 mm.
13 . The additive fabrication device of claim 1 , wherein the first material layer has a thickness between 0.001″ and 0.01″.
14 . The additive fabrication device of claim 1 , wherein the first material layer is a fiber composite film.
15 . The additive fabrication device of claim 1 , wherein the barrier layer and the first material layer are transparent to the actinic radiation.