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.

Abstract: A water dispersible sulfopolymer for use as a material in the layer-wise additive manufacture of a 3D part made of a non water dispersible polymer wherein the water dispersible polymer is a reaction product of a metal sulfo monomer, the water dispersible sulfo-polymer being dispersible in water resulting in separation of the water dispersible polymer from the 3D part made of the non water dispersible polymer.

Abstract: The present invention relates to a method for producing an object in an additive manufacturing process from a precursor and comprises the following steps: I) depositing a layer of a radically cross-linkable construction material, which corresponds to a first selected cross-section of the precursor, on a carrier; II) depositing a layer of a radically cross-linkable construction material, which corresponds to a further selected cross-section of the precursor, on a previously applied layer of the radically cross-linked construction material; III) repeating step II) until the precursor is formed. The radically cross-linkable construction material comprises a thermoplastic radically cross-linkable polyurethane with a urethane group content of ?5% by weight and a photoinitiator. The radically cross-linkable construction material is also heated to a processing temperature that is greater than the melting point of the radically cross-linkable polyurethane. After step III) the precursor having a temperature of 20° C.

Abstract: The present invention relates to a fire, smoke and toxicity retardant (FST) polyamide thermoplastic mass usable for 3D printing which comprises at least one non-halogenated organic flame retardant in combination with at least one particulate inorganic flame retardant. Moreover, the present invention refers to uses of such FST polyamide thermoplastic mass for 3D printing. The invention further relates to methods of preparing a three-dimensionally shaped product by means of 3D printing based on such FST polyamide thermoplastic mass.

Abstract: The present invention relates to a method for producing an at least partially coated object and to an at least partially coated object obtained by the method. The method comprises bringing the object completely or partly into contact with a treating agent; leaving the object at 10° C.-30° C. and 100 mbar-800 mbar for 3-10 minutes; and heat-treating the object at a temperature of 70° C.-90° C.

Abstract: A 3D printer includes a gantry configured to move in a plane and in a direction substantially normal to the plane and at least one print head carried by the gantry, the at least on print head comprising an extrusion nozzle at a bottom end. The 3D printer includes a plurality of partitioned chambers accessible by the at least one print head, each of the partitioned chambers having an upper edge defining an opening into each of the plurality of chambers, and a platen within a first chamber of the plurality of chambers, the platen configured to receive material from the print head to print the 3D part.

Abstract: A light engine (32) for a three-dimensional printer (10) includes a plurality of light emitting diodes (LEDs) (404a, 404b, 404c, 404d) arranged into respective groups (321), each respective group of LEDs (321) including one or more LEDs, e.g., LEDs of different wavelengths. Corresponding to each respective LED group (321) is a respective light pipe (323) for receiving outputs of radiation from each the LEDs of the respective group (321) and providing an output of the light pipe (323), and a respective telecentric optical system (320) for collimating the output of the respective light pipe (323) to provide a collimated output of the respective LED group (321).

Abstract: Aspects are described for use in additive manufacturing. A desired manufacturing path may be specified for a 3D model of an object to manufacture via additive manufacturing. The object may be a load-bearing structure. The desired manufacturing path may be based on the expected mechanical stress on the object. Slicing the 3D model may provide toolpath segments corresponding to a toolpath of an additive manufacturing apparatus. The toolpath segments may be sorted and oriented based on the desired manufacturing paths. Additive manufacturing control instructions may be generated based on the sorted and oriented toolpath segments. The additive manufacturing control instructions may be used to control the toolpath of an additive manufacturing apparatus in accordance with the desired manufacturing paths when manufacturing the object via an additive manufacturing process.

Abstract: A 3D printing system may include a tank in which a bottom of the tank is formed by a radiation-transparent flexible membrane, a spill tray with an outer wall configured to contain liquid resin that inadvertently leaks out from the bottom of the tank, and a light source configured to project radiation towards the bottom of the tank. The spill tray may contain an inner opening that allows the radiation from the light source to pass through the spill tray to the tank. A 3D printing system may also include a mask assembly which comprises a mask with pixels configurable to be individually transparent or opaque to portions of the radiation projected from the light source and a mask assembly receiving member configured to receive the mask assembly. The mask assembly may also include a rigid guide portion that is insertable into a slot of the mask assembly receiving member.

Abstract: A process for automatically adjusting print speed in a 3D printer, a system for printing a 3D object, and a method of printing a 3D object. A scaling factor is selected, including a first component for print speed and a second component for print quality, an extrusion nozzle port size is identified, and a maximum volumetric extrusion rate for a filament material and a minimum volumetric extrusion rate for the filament material is identified. An optimized volumetric extrusion rate is calculated from the maximum volumetric extrusion rate, the minimum volumetric extrusion rate, and the scaling factor. An optimized X-Y velocity Vxy of a print head based on the optimized volumetric extrusion rate is calculated. A computer numerical control code is adjusted to include the optimized X-Y velocity Vxy of the print head.

Abstract: A method of additive manufacturing comprises operating an additive manufacturing system for fabricating a multiplicity of objects, while acquiring a set of images during fabrication of each of the objects. For each object, a respective set of images is analyzed to identify fabrication irregularities, and a fabrication score is generated based on the irregularities. The multiplicity of objects is clustered according to the fabrication scores into at least two clusters.

Abstract: A 3D printer includes a holding area holding material to be used to produce a part and at least one component for producing the part through layer-wise additive manufacturing. A data storage device in the 3D printer stores instructions for generating build parameter values, the instructions including empirically derived data, relationships, and/or equations. A processor in the 3D printer receives values for a public build parameter set and a category for the material wherein the category represents multiple different materials. The processor executes instructions to determine values for a private build parameter set that vary based on the properties of the material. The values for the private build parameter set are determined from the received values for the public build parameter set and the received category. The processor then uses the received values for the public build parameter set and the values for the private build parameter set to build the part.