Abstract: A polymeric material used for 3D printing is preheated, at a first zone in a 3D printer, to a temperature in excess of its glass transition temperature prior to being melted, at a second zone, for incorporation into a build object. This enables the polymer to be processed more rapidly than in the prior art.

Abstract: It is a feature of a porous body (10, 20) comprising a three-dimensional network of node points (200) joined to one another by struts (100), and a void volume (300) present between the struts (100), that the struts (100) have an average length of ?200 to ?50 mm, the struts (100) have an average thickness of ?100 ?m to ?5 mm, and that the porous body has a compression hardness (40% compression, DIN EN ISO 3386-1: 2010-09) in at least one spatial direction of ?10 to ?100 kPa. The porous body according to the invention combines the advantages of a conventional mattress or cushion with ventilatability which results from its porous structure and is not achievable in conventional foams. The invention further relates to a method of producing such a porous body (10, 20) and to an apparatus comprising said body (10, 20) for supporting and/or bearing a person.

Abstract: The invention relates to a method for producing a polymer comprising the following steps: (A) depositing a radically cross-linkable resin, obtaining a radically cross-linked resin; and (B) treating the radically cross-linked resin under conditions which are sufficient to trigger a chemical reaction that is different from the radical cross-linking in the radically cross-linked resin. The radically cross-linkable resin comprises a curable component, in which there are NCO groups, olefinic C?C double bonds and epoxide groups, and the chemical reaction in the radically cross-linked resin that is different from the radical cross-linking is the reaction of NCO groups and epoxide groups to form oxazolidinone groups.

Abstract: A platen assembly for use with an extrusion-based 3D printer includes a grid assembly comprising at least a 4×2 framework of interlocked perpendicular x direction beams and y direction beams, providing a substantially planar upper surface and a bottom surface. The platen assembly includes a platen comprising a thin metal sheet supported on the upper surface of the grid assembly and secured to the grid assembly such that the top surface provides a substantially flat build surface. The x direction beams, the y direction beams and the platen are constructed of substantially a same thermal expansion properties, and wherein the build surface of the platen has a build surface area of at least 400 square inches and maintains its flatness to within a flatness tolerance of 0.020 inches over a temperature range of at least 20 C-300 C.

Abstract: Provided is a photopolymerizable composition comprising a blend of: a) from 40 wt. % to 70 wt. % of at least one urethane component; b) from 25 wt. % to 70 wt % of at least one monofunctional reactive diluent; c) from 0.1 wt. % to 5 wt. % of at least one initiator; and d) from 2 wt. % to 10 wt % of an amine-functional (meth)acrylate monomer. Also provided is a process of producing a photopolymerizable composition by blending these ingredients. Further provided is a process of producing a three-dimensional object, by depositing the photopolymerizable composition atop a carrier; depositing additional photopolymerizable composition atop a previously applied layer wherein the depositing of the photopolymerizable composition comprises introducing energy.

Abstract: The present disclosure is directed to pulverulent thermoplastic polymer blends comminuted to a particle size of less than 300 ?m. The pulverulent thermoplastic polymer blends can include a first thermoplastic polyurethane and a second thermoplastic polyurethane at a weight ratio of from about 90:10 to about 30:70 first thermoplastic polyurethane to second thermoplastic polyurethane. The first thermoplastic polyurethane can include a reaction product of a first reaction mixture consisting of or consisting essentially of an aliphatic diisocyanate having a number average molecular weight of from 140 g/mol to 170 g/mol and an aliphatic diol having a number average molecular weight of from 62 g/mol to 120 g/mol.

Abstract: The hardware and software properties of a three-dimensional printer can be queried and applied to select suitable directly printable models for the printer, or to identify situations where a new machine-ready model must be generated. The properties may be any properties relevant to fabrication including, e.g., physical properties of the printer, printer firmware, user settings, hardware configurations, and so forth. A printer may respond to configuration queries with a dictionary of capabilities or properties, and this dictionary may be used to select suitable models, or determine when a new model must be created. Similarly, when a printable model is sent to the printer, metadata for the printable model may be compared to printer properties in the dictionary to ensure that the model can be fabricated by the printer.

Abstract: A filament for use in an extrusion-based additive manufacturing system includes an elastomeric core and a harder, non-elastomeric shell. The core compositionally comprising an elastomeric core material having a flexural modulus of less than 31,000 psi and a durometer of less than 80 Shore. The shell overlays the core portion and compositionally comprises a non-elastomeric thermoplastic shell material that is substantially miscible with the elastomeric core material, wherein the core material and the shell material have the same monomer chemistry. The non-elastomeric thermoplastic shell material has a flexural modulus that is greater than the flexural modulus of the elastomeric core material by at least a factor of five, wherein the shell provides sufficient strength or stiffness to the filament such that filament can be utilized as a feedstock in the extrusion-based additive manufacturing system.

Abstract: An additive manufacturing system including a base assembly and a tray assembly. The base assembly includes a build window, substantially transparent to electromagnetic radiation; a projection system configured to project electromagnetic radiation toward an upper surface of the build window; and a tray seat arranged around a perimeter of the build window. The tray assembly is configured to engage with the base assembly in an engaged configuration and includes: a tray structure defining a registration feature configured to engage the tray seat to locate an aperture proximal to the upper surface of the build window in the engaged configuration; and a separation membrane that is configured to laminate across the upper surface of the build window in response to an evacuation of gas from an interstitial region and configured to separate from the build window in response to injection of gas into the interstitial region.

Abstract: Radiation curable compositions for additive fabrication processes, the components cured therefrom, and their use in particle image velocimetry testing methods are described and claimed herein. Such compositions include compounds which induce free-radical polymerization, optionally compounds which induce cationic polymerization, a filler constituent, and a light absorbing component, wherein the compositions are configured to possess certain absorbance values at wavelengths commonly utilized in particle image velocimetry testing. In another embodiment, the compositions include a fluoroantimony-modified compound. Such compositions may be used in particle imaging velocimetry testing methods, wherein the test object utilized is created via additive fabrication and is of a substantially homogeneous construction.

Abstract: Liquid radiation curable compositions are disclosed which are suitable for hybrid (i.e. cationic and free-radical) polymerization when processed via additive fabrication equipment utilizing sources of actinic radiation with peak spectral intensities in the UV/vis region. According to one aspect, the compositions possess a first photoinitiator that is an iodonium salt of a non-fluorinated borate anion. According to another aspect, the composition is substantially devoid of a Norrish Type I and/or Type II photoinitiator. Also disclosed are methods of creating three-dimensional parts via additive fabrication processes utilizing sources of actinic radiation with peak spectral intensities in the UV/vis region employing liquid radiation curable compositions suitable for hybrid polymerization, and the parts cured therefrom.

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: A build chamber for a 3D printer includes a heated build space in an interior of the build chamber and a thermal isolator configured to insulate 3D printer components from the heated build space. The thermal isolator includes a first baffle section and a second baffle section. Each of the first baffle section and the second baffle section includes an accordion-pleated panel having a length, a width, a first end and a second end, wherein the panel comprises a parallel alternating top folds and bottom folds along the width forming a series of pleats, and each pleat within the series being configured to expand and contract, and wherein the panel is constructed of a heat-resistant material. Each baffle section also includes support rods affixed to the accordion-pleated panel in parallel to the pleats and at intervals along the length of the panel, the support rods substantially spanning the width of the panel.

Abstract: It is a feature of a use of an elastic polymer for production of a porous body (in an additive manufacturing method that the porous body comprises a three-dimensional network of node points joined to one another by struts, and a void volume present between the struts, where the struts have an average length of ?200 ?m to ?50 mm and the struts (100) have an average thickness of ?100 ?m to ?5 mm. The polymer here is an elastomer selected from the following group: thermoset polyurethane elastomers (PUR), thermoplastic copolyamides (TPA), thermoplastic copolyesters (TPC), thermoplastic olefin-based elastomers (TPO), styrene block copolymers (TPS), thermoplastic urethane-based elastomers (TPU), crosslinked thermoplastic olefin-based elastomers (TPV), thermoplastic polyvinyl chloride-based elastomers (PVC), thermoplastic silicone-based elastomers and a combination of at least two of these elastomers.

Abstract: A method for generating print images for additive manufacturing includes: accessing a part model; accessing a set of dimensional tolerances for the part model; and segmenting the part model into a set of model layers. The method also includes, and, for each model layer: detecting an edge in the model layer; assigning a dimensional tolerance to the edge; defining an outer exposure shell inset from the edge by an erosion distance inversely proportional to a width of the dimensional tolerance; defining an inner exposure shell inset from the outer exposure shell and scheduled for exposure separately from the outer exposure shell; defining an a outer exposure energy proportional to the width of the dimensional tolerance and assigned to the outer exposure shell; and defining an inner exposure energy greater than the outer exposure energy and assigned to the inner exposure shell.

Abstract: Matrix-filled liquid radiation curable resin compositions for additive fabrication are described and claimed. Such resins include a cationically polymerizable component that is an aliphatic epoxide, a multifunctional (meth)acrylate component, a cationic photoinitiator, a free-radical photoinitiator, and a matrix of inorganic fillers, wherein the matrix further constitutes prescribed ratios of at least one microparticle constituent and at least one nanoparticle constituent. Also described and claimed is a process for using the matrix-filled liquid radiation curable resins for additive fabrication to create three dimensional parts, and the three-dimensional parts made from the liquid radiation curable resins for additive fabrication.

Abstract: The present invention relates to a method for producing a treated object, comprising the steps of: applying a layer of particles to a target area; applying a liquid binder to a selected portion of the layer in accordance with a cross-section of the object, so that the particles in the selected portion are bonded; repeating the steps of applying a layer of particles and applying a binder for a plurality of layers so that the bonded portions of the adjacent layers are bonded to form an object, wherein at least a part of the particles comprises a meltable polymer. A binder which cures by cross-linking is preferably selected as the binder. The obtained object is at least partially contacted with a liquid heated to ?T or with a powder bed heated to ?T in order to obtain the treated object. T represents a temperature of ?25° C.

Abstract: Adhesive compositions comprising an aqueous dispersion of an acrylic polymer are disclosed, with such compositions having particular applicability in additive manufacturing processes, such as three-dimensional (3D) printing, including Fused Filament Fabrication (FFF). In particular, the compositions address drawbacks associated with an improper degree of adhesion between a thermoplastic build material and build plate, which decrease the quality of printed objects. In representative aqueous dispersions, the solids content of at least about 5 wt. % and also most about 95 wt. % of the acrylic polymer is solubilized, with the balance of this polymer comprising dispersed solid particles.