Abstract: In one example, a process for depowdering an elastic object made with a 3D printer using powdered build material includes compressing the object progressively from one end of the object to another end of the object.

Abstract: In some examples, a system defines sub-volumes within a bounding object based on beams of a unit cell of a lattice structure for a 3D object to be built. The sub-volumes are defined based on the beams cutting through the bounding object that contains the unit cell. The system intersects the sub-volumes of the bounding object with a trimmed version of the lattice structure. The system forms a surface lattice structure having beams identified based on the intersecting, the beams of the surface lattice structure to connect to unit cells of the trimmed version of the lattice structure.

Abstract: This disclosure relates to a material set including a build material for 3-D printing including particles of a polymer comprising polymer chains having at least one reactive group that is protected with a protecting group. The material set further includes an inkjet composition including a de-protecting agent for removal of the protecting group, and a liquid carrier.

Abstract: This disclosure relates to a material set including a build material for 3-D printing including particles of a polymer comprising polymer chains having at least one reactive group that is protected with a protecting group. The material set further includes an inkjet composition including a de-protecting agent for removal of the protecting group, and a liquid carrier.

Abstract: This disclosure relates to a material set including a build material for 3-D printing including particles of a polymer comprising polymer chains having at least one reactive group that is protected with a protecting group. The material set further includes an inkjet composition including a de-protecting agent for removal of the protecting group, and a liquid carrier.

Abstract: An example of an anti-coalescing agent for a three-dimensional (3D) printing process includes a vehicle and an anti-coalescing polymer dispersed in the vehicle. The vehicle includes a co-solvent, a surfactant, a humectant, and water. The anti-coalescing polymer has a mean particle size ranging from about 50 nm to about 195 nm, and the anti-coalescing polymer is to coat polymeric build material particles to prevent the polymeric build material particles from coalescing during electromagnetic radiation exposure of the 3D printing process.

Abstract: A multi-fluid kit for three-dimensional printing includes a fusing agent and a fluorescing detailing agent. The fusing agent includes water and a radiation absorber. The radiation absorber absorbs radiation energy and converts the radiation energy to heat. The fluorescing detailing agent includes water and a fluorescent colorant that is active by exposure to ultraviolet energy to emit light in the visible range of from about 400 nm to about 780 nm. The multi-fluid kit is devoid of a second detailing agent and a second fluorescent colorant.

Abstract: This disclosure relates to a method of 3-D printing comprising: applying a layer of build material onto a print platform, wherein the build material comprises particles of a polymer comprising polymer chains having at least one reactive group that is protected with a protecting group; printing a de-protecting agent at selected locations on the layer of build material; and coalescing particles of the polymer at the printed locations on the layer of build material to form a coalesced polymer layer.

Abstract: An example of an anti-coalescing agent for a three-dimensional (3D) printing process includes a vehicle and an anti-coalescing polymer dispersed in the vehicle. The vehicle includes a co-solvent, a surfactant, a humectant, and water. The anti-coalescing polymer has a mean particle size ranging from about 50 nm to about 195 nm, and the anti-coalescing polymer is to coat polymeric build material particles to prevent the polymeric build material particles from coalescing during electromagnetic radiation exposure of the 3D printing process.

Abstract: In an example of a method for 3D printing, a polymeric or polymeric composite build material is applied. Some of the build material is negatively patterned to define a removable build material portion and a remaining build material portion. The negatively patterning includes selectively applying an anti-coalescing polymer solution including a polymer having a pendant reactive functional group, and selectively applying an anti-coalescing crosslinker solution including a multifunctional crosslinker. The pendant reactive functional group and the multifunctional crosslinker react to form an insoluble gel network among the polymeric or polymeric composite build material in the removable build material portion. Based on a 3D object model, a layer of a final 3D object is formed from at least some of the remaining build material portion. The some of the polymeric or polymeric composite build material in the removable build material portion remains physically separated from the layer.

Abstract: This disclosure relates to a method of 3-D printing comprising: applying a layer of build material onto a print platform, wherein the build material comprises particles of a polymer comprising polymer chains having at least one reactive group that is protected with a protecting group; printing a de-protecting agent at selected locations on the layer of build material; and coalescing particles of the polymer at the printed locations on the layer of build material to form a coalesced polymer layer.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition and a fusing agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition includes a polyether block amide polymer. The fusing agent includes an energy absorber to absorb electromagnetic radiation to melt or fuse the at least a portion of the polyether block amide polymer.

Abstract: In a coating method example, a coating is formed on a part precursor by blasting the part precursor with a blast medium. The blast medium includes blasting beads and a coating agent. The part precursor is formed from a polymeric build material, and a hardness of the blasting beads is greater than a hardness of the polymeric build material.

Abstract: In an example of a method for 3D printing, a polymeric or polymeric composite build material is applied. Some of the build material is negatively patterned to define a removable build material portion and a remaining build material portion. The negatively patterning includes selectively applying an anti-coalescing polymer solution including a polymer having a pendant reactive functional group, and selectively applying an anti-coalescing crosslinker solution including a multifunctional crosslinker. The pendant reactive functional group and the multifunctional crosslinker react to form an insoluble gel network among the polymeric or polymeric composite build material in the removable build material portion. Based on a 3D object model, a layer of a final 3D object is formed from at least some of the remaining build material portion. The some of the polymeric or polymeric composite build material in the removable build material portion remains physically separated from the layer.

Abstract: In a coating method example, a coating is formed on a part precursor by blasting the part precursor with a blast medium. The blast medium includes blasting beads and a coating agent. The part precursor is formed from a polymeric build material, and a hardness of the blasting beads is greater than a hardness of the polymeric build material.

Abstract: An art frame includes a three-dimensional supporting frame having an image receiving surface and a back surface opposed thereto, and a center portion defining a perimeter from which at least three foldable extensions extend. Each foldable extension includes no less than four folds folded toward the back surface to form a frame portion having an outer wall substantially perpendicular to the back surface, and an inner wall substantially perpendicular to the back surface and substantially parallel to the outer wall. A compressible member is attached to the outer walls to adhere an image receiving medium to the supporting frame. Compressible member includes a first adhesive on the outer walls, a polymer foam substrate (having a compression index ranging from about 0.4 to about 0.8) on the first adhesive, and a second adhesive on the polymer foam substrate. Second adhesive is to secure the image receiving medium to the supporting frame.

Abstract: An art frame includes a three-dimensional supporting frame having an image receiving surface and a back surface opposed thereto, and a center portion defining a perimeter from which at least three foldable extensions extend. Each foldable extension includes no less than four folds folded toward the back surface to form a frame portion having an outer wall substantially perpendicular to the back surface, and an inner wall substantially perpendicular to the back surface and substantially parallel to the outer wall. A compressible member is attached to the outer walls to adhere an image receiving medium to the supporting frame. Compressible member includes a first adhesive on the outer walls, a polymer foam substrate (having a compression index ranging from about 0.4 to about 0.8) on the first adhesive, and a second adhesive on the polymer foam substrate. Second adhesive is to secure the image receiving medium to the supporting frame.

Abstract: Image forming apparatuses and methods are disclosed. Image forming apparatuses and methods include a plate member including an upper plate surface to receive media on which to form images, an ink absorber member to receive ink in a form of ink build-up, and a blotter unit to periodically contact and press at least a portion of the ink build-up formed on the ink absorber member therein.

Abstract: In one embodiment, an aerosol particle collector includes a duct defining a flow path configured to remove larger particles from aerosol flowing through the duct and to store the removed particles in the duct while maintaining a uniform rate of aerosol flow throughout a predetermined useful life of the duct even as stored aerosol particles accumulate in the duct. In another embodiment, an aerosol particle collector includes a duct and a plurality of baffles in the duct. The duct has an elongated inlet extending along a length of the duct and an outlet located at one end of the length of the duct. A first one of the baffles extends along a first side of the duct for deflecting incoming aerosol toward a second side of the duct opposite the first side. A second one of the baffles is for deflecting aerosol toward the outlet.

Abstract: In one embodiment, an aerosol particle collector includes a duct defining a flow path configured to remove larger particles from aerosol flowing through the duct and to store the removed particles in the duct while maintaining a uniform rate of aerosol flow throughout a predetermined useful life of the duct even as stored aerosol particles accumulate in the duct. In another embodiment, an aerosol particle collector includes a duct and a plurality of baffles in the duct. The duct has an elongated inlet extending along a length of the duct and an outlet located at one end of the length of the duct. A first one of the baffles extends along a first side of the duct for deflecting incoming aerosol toward a second side of the duct opposite the first side. A second one of the baffles is for deflecting aerosol toward the outlet.