Abstract: A resin comprises: A) a multifunctional (meth)acrylate; B) an NCO-functional polyurethane; C) a radical starter and D) a catalyst. The multifunctional (meth)acrylate A) has a viscosity at 23° C. as determined according to DIN EN ISO 2884-1 of ?10000 mPa·s, the NCO-functional polyurethane B) has an average NCO group functionality of ?2 and an equivalent molecular weight with respect to NCO groups of >300 g/mol, the catalyst D) is an isocyanate trimerization catalyst and the resin is free from NCO-reactive compounds or, if NCO-reactive compounds are present in the resin, the molar ratio of NCO groups to NCO-reactive groups is ?5:1.

Abstract: A feedstock configured for use in an extruder in an additive manufacturing system is configured as a braided comingled tow filament. A method of producing the braided comingled tow filament includes providing a bundle of comingled tow material having a fiber count ranging from about 1,000 fibers to about 25,000 fibers having thermoplastic fibers comingled therewith, wherein the tow material in the filament ranges from about 50 to 75 volume percent and the volume percent of the thermoplastic material ranges from about 25 volume percent to about 50 volume percent. The method includes dividing the length of comingled tow material into sections, twisting each section into a strand to form a plurality of strands of twisted tow material, and braiding together the strands.

Abstract: A method for printing a three-dimensional part with an additive manufacturing system, which includes providing a part material that compositionally has one or more semi-crystalline polymers and one or more secondary materials that are configured to retard crystallization of the one or more semi-crystalline polymers, where the one or more secondary materials are substantially miscible with the one or more semi-crystalline polymers. The method also includes melting the part material in the additive manufacturing system, forming at least a portion of a layer of the three-dimensional part from the melted part material in a build environment, and maintaining the build environment at an annealing temperature that is between a glass transition temperature of the part material and a cold crystallization temperature of the part material.

Abstract: Radiation curable compositions for additive fabrication with improved toughness are described and claimed. Such resins include a rubber toughenable base resin package and a liquid, phase-separating toughening agent. The rubber toughenable base resin, which may possess a suitably high average molecular weight between crosslinks and may be a pre-reacted hydrophobic macromolecule, may further include a cationically polymerizable component, a radically polymerizable component, a cationic photoinitiator, a free radical photoinitiator, and customary additives. Also described and claimed are methods for forming a three-dimensional objects using such radiation curable compositions for additive fabrication with improved toughness, along with the three-dimensional parts created therefrom.

Abstract: A 3D printer includes a chamber configured to receive extruded material to print a part and a tool chamber above the chamber, the tool chamber comprising a viewing window and a tool rack. The 3D printer includes a plurality of print heads, each of the plurality of print heads residing in a docked position on the tool rack and when not in use. Each of the plurality of print heads comprising a illuminated status indicator configured to emit a plurality of signals indicative of a status or error of the print head or a status of the 3D printer, wherein the illuminated status indicator faces the viewing window and a plurality of sensors located on the print head or in the 3D printer and configured to detect a status of the print head or other printer components or an error in the print head or other printer components.

Abstract: An extrusion-based 3D printer configured to print 3D parts in a layer-by-layer manner includes a platen configured to accept and support extruded material, at least one print head configured to extrude material to print a 3D part and a gantry configured to move the at least one print head as the material is extruded. The 3D printer includes at least one head carriage configured to engage the at least one print head. The at least one carriage is configured to engage and retain the at least one print head, where a filament cutter positioned above the at least one print head. The filament cutter includes a blade configured to be moved by the user, such that the blade is positionable between a non-cutting position where filament can be fed to the at least one print head and a cutting position wherein the filament is cut above the print head.

Abstract: Described herein are thermoset compositions and kits of compositions suitable for use in additive fabrication processes including specified concentrations of reactive compounds including urethane-(meth)acrylate compounds, monofunctional diluent monomers, and methacrylate-functional compounds having 1.5 polymerizable groups or more. Also described and claimed are methods of creating three-dimensional parts via additive fabrication processes utilizing the compositions elsewhere herein described and claimed, as well as the articles cured therefrom.

Abstract: The present invention is directed to certain biodegradable and/or compostable biobased particulate compositions for additive manufacturing, such as those including a polyhydroxyalkanoate (PHA) powder, wherein the particulate composition and/or the PHA powder possesses (a) a free bulk density, as determined by ASTM D1895-96, of greater than 0.30 g/mL, and (b) a sinterability region of greater than 15 degrees Celsius. Also, the invention is directed to certain methods of manufacturing such biodegradable and/or compostable biobased particulate compositions useful as powdered build material for additive manufacturing processes. In addition, the present invention is directed to additive manufacturing processes utilizing the biodegradable and/or compostable biobased particulate compositions elsewhere described, along with the articles printed therefrom.

Abstract: A method of printing a multi-material part in a layer-wise manner with an extrusion-based 3D printer includes providing a sliced digital model of a multi-material part and determining a number of materials in each of the slices of the digital mode. The method includes utilizing a digital model of a purge tower having N subdivisions having a closed geometry, wherein N is the number of print heads needed to print the part that is greater than or equal to three, each adjacent subdivision contact one another along an interface and assigning each print head to one subdivision and to tool paths forming the one subdivision in each layer. The method includes reassigning the assigned subdivision within the purge tower of an inactive print head in a layer to a print head that is active in the layer of the multi-material part.

Abstract: A 3D printer includes an enclosed build chamber thermally separated from a tool chamber. An upward-facing tool tray coupled to or integral with a carriage has an open bottom providing a tool port for accessing the heated build chamber. A thermal barrier is mounted in the tool tray, covering the tool port but penetrable through an aperture thereof. The aperture provides an entry point to the build chamber for a working end of an active print head, wherein when the working end is positioned though the aperture, the tool port is substantially closed.

Abstract: Provided is a composition comprising: A) an aliphatic polyurethane which comprises a reaction product of a first aliphatic polyisocyanate, a first polyol, and a thiol, optionally in the presence of a catalyst, and B) a urethane (meth)acrylate prepolymer, optionally a reactive diluent, and a photoinitiator, wherein the urethane (meth)acrylate prepolymer comprises a reaction product of a second aliphatic polyisocyanate, a second polyol and an acrylate, wherein the reactive diluent comprises a (meth)acrylate monomer, wherein the first aliphatic polyisocyanate and second aliphatic polyisocyanate may be identical or different, and wherein the first polyol and the second polyol may be identical or different.

Abstract: A method of printing a plurality of parts with varying layer heights in a single print job in a 3D printer includes providing a plurality of sliced 3D digital representations of a plurality of parts with varying slice heights in the Z direction, positioning the digital representation of parts on a build platform of the 3D printer and determining a printing sequence of the layers of the parts based upon a lowest Z height between the plurality of sliced 3D digital representations. The method further includes extruding the layers of the plurality of disjoined parts with one or more print heads based upon the determined printing sequence and intermittently indexing z height between the sequenced layers until each of the plurality of parts is printed.

Abstract: A method includes: accessing a part model comprising a three-dimensional representation of a part; accessing a material profile relating exposure energy and three-dimensional polymerization geometry of a material selected for the part; segmenting the part model into a set of model layers; detecting a first upward-facing surface in the part model; defining a first model volume in a first model layer, adjacent the first upward-facing surface, and fully contained within the part model; based on the material profile, calculating a first exposure energy predicted to yield a first three-dimensional polymerization geometry approximating a first contour of the first upward-facing surface when projected onto the material during a build; populating a first print image with the first exposure energy in a first image area corresponding to the first model volume in the first model layer; and storing the first print image in a print file for the part.

Abstract: The present invention relates to a process for the production of a composite article comprising a structured porous body (PB) and a particle foam (PF), wherein the provided structured porous body (PB) is inserted into a mould (M) and the mould (M) is filled with expanded foam beads (EFB) so that the expanded foam beads (EFB) are in contact with each other and the structured porous body (PB) is at least partially in contact with the expanded foam beads (EFB). Then, the expanded foam beads (EFB) are thermally welded, wherein the particle foam (PF) is built and the composite article is obtained. Moreover, the present invention relates to a composite article obtained by this process, as well as to a composite article comprising a structured porous body (PB) and a particle foam (PF).

Abstract: A tensioning apparatus for manufacturing a membrane assembly for a three-dimensional printer. The tensioning apparatus may include a base portion, an upper portion, and a jig configured to receive a lower frame piece of a membrane assembly. The jig is arranged on the base portion and shaped to receive a lower frame piece of the membrane assembly. The base portion has a number of holes through an upper plate thereof through which air can be evacuated from the tensioning apparatus when a flexible membrane material is being fitted to the lower frame piece of the membrane assembly.