Abstract: A three-dimensional (3D) printing method includes applying a build material composition having a polymer particle and a radiation absorbing additive mixed with the polymer particle, the radiation absorbing additive being selected from the group consisting of inorganic near-infrared absorbers, organic near-infrared absorbers, and combinations thereof. The build material composition is preheated to a temperature below the melting temperature of the polymer particle by exposing the build material composition to radiation, the radiation absorbing additive increasing radiation absorption and accelerating the pre-heating of the build material composition. A fusing agent is selectively applied on at least a portion of the build material composition. The method further includes exposing the build material composition to radiation, whereby at least the polymer particle in the at least the portion of the build material composition in contact with the fusing agent at least partially fuses.

Abstract: An example of a fusing agent includes a metal bis(dithiolene) salt, a polar aprotic solvent, and a balance of water. An example of a method for making an example of the fusing agent includes adding a metal bis(dithiolene) salt into a liquid vehicle including at least a polar aprotic solvent and water.

Abstract: In an example of a method for forming three-dimensional (3D) printed electronics, a build material is applied. A fusing agent is selectively applied on at least a portion of the build material. The build material is exposed to radiation and the portion of the build material in contact with the fusing agent fuses to form a layer. An electronic agent is selectively applied on at least a portion of the layer, which imparts an electronic property to the at least the portion of the layer.

Abstract: According to an example, a composition may include a high melt temperature build material in the form of a powder; a first low melt temperature binder in the form of a powder; and a second low melt temperature binder in the form of a powder; and in which the first low melt temperature binder melts at a temperature that is different from the second low melt temperature binder.

Abstract: In one example, an apparatus for generating a three-dimensional object includes an energy source to apply energy to a layer of build material to cause a first portion of the layer to coalesce and solidify, an agent distributor to selectively deliver a cooling agent onto a second portion of the layer, and a controller to control the energy source to apply energy to the layer to cause the first portion to coalesce and solidify in a first pattern and to control the agent distributor to selectively deliver the cooling agent onto the second portion of the layer in a second pattern independent of the first pattern.

Abstract: In an example of a method for forming three-dimensional (3D) printed electronics, a build material is applied. A fusing agent is selectively applied on at least a portion of the build material. The build material is exposed to radiation and the portion of the build material in contact with the fusing agent fuses to form a layer. An electronic agent is selectively applied on at least a portion of the layer, which imparts an electronic property to the at least the portion of the layer.

Abstract: A device includes a carriage movable relative to a build pad along a bi-directional travel path and supporting at least a radiation source and an applicator to selectively apply a plurality of fluid agents, including first fluid agents to affect a first material property. A timing and order of operation of the radiation source and the applicator, with the carriage, is to maintain first and second portions of a 3D object under formation within at least one selectable temperature range despite a first total volume of the first fluid agents for application onto the first portion of the 3D object being substantially greater than a second total volume of second fluid agents for application onto the second portion of the 3D object.

Abstract: An example of a fusing agent includes a metal bis(dithiolene) salt, a polar aprotic solvent, and a balance of water. An example of a method for making an example of the fusing agent includes adding a metal bis(dithiolene) salt into a liquid vehicle including at least a polar aprotic solvent and water.

Abstract: In one example, a lighting device for an additive manufacturing machine includes first light sources each to emit monochromatic light within a first band of wavelengths that includes a peak light absorption of a liquid coalescing agent and second light sources each to emit monochromatic light within a second band of wavelengths different from the first band of wavelengths. Each of the first light sources or each of multiple groups of the first light sources is individually addressable to emit monochromatic light independent of any other of the first light sources or of any other group of the first light sources and each of the second light sources or each of multiple groups of the second light sources is individually addressable to emit monochromatic light independent of any other of the second light sources or of any other group of the second light sources.

Abstract: In one example, a lighting device for an additive manufacturing machine includes an array of light sources each to emit monochromatic light within a band of wavelengths that includes a peak light absorption of a liquid coalescing agent to be dispensed on to a build material.

Abstract: An example of a fusing agent includes a metal bis(dithiolene) salt, a polar aprotic solvent, and a balance of water. An example of a method for making an example of the fusing agent includes adding a metal bis(dithiolene) salt into a liquid vehicle including at least a polar aprotic solvent and water.

Abstract: Apparatus and methods for making metal-connected particle articles. A metal containing fluid is selectively applied to a layer of particles. The metal in the fluid is used to form metal connections between particles. The metal connections are formed at temperatures below the sintering temperature of the particles in the layer of particles.

Abstract: Methods of forming 3D printed metal objects and compositions for 3D printing are described herein. In an example, a method of forming a 3D printed metal object can comprise: (A): a build material comprising at least one metal being deposited; (B): a fusing agent being selectively jetted on the build material, the fusing agent comprising: (i) at least one hydrated metal salt having a dehydration temperature of from about 100° C. to about 250° C., and (ii) a carrier liquid comprising at least one surfactant and water; (C): the build material and the selectively jetted fusing agent being heated to a temperature of from about 100° C. to about 250° C. to: (a) remove the carrier liquid, (b) dehydrate the hydrated metal salt, and (c) bind the build material and the selectively jetted fusing agent; and (D): (A), (B), and (C) being repeated at least one time to form the 3D printed metal object.

Abstract: Apparatus and methods for making metal-connected particle articles. A metal containing fluid is selectively applied to a layer of particles. The metal in the fluid is used to form metal connections between particles. The metal connections are formed at temperatures below the sintering temperature of the particles in the layer of particles.

Abstract: A three-dimensional printing system includes a controller to instruct a fusing agent distributor to selectively apply a fusing agent to a first region of a layer of build material. The controller also determines a subset of voxels in the layer of build material to provide an opacifying agent based on an opacity value of an opacified region of an object to be generated and instructs an opacifying agent distributor to apply the opacifying agent to the determined subset of voxels.

Abstract: A 3D printer to additively manufacture a 3D object includes a coater, a dispenser, and an energy source. The coater is to coat a first material relative to a print bed to form a selectable number of first layers. The dispenser is to dispense a first fluid agent onto first selected locations of the first layers of the first material. The energy source is to cause fusing at the first selected locations. The dispenser is to also dispense a second fluid agent including a second material to form a selectable number of second layers of the second material at second selected locations on top of the selectable number of first layers. Each second selected location comprises at least some of the fused first selected locations.

Abstract: An example of a fusing agent includes a metal bis(dithiolene) salt, a polar aprotic solvent, and a balance of water. An example of a method for making an example of the fusing agent includes adding a metal bis(dithiolene) salt into a liquid vehicle including at least a polar aprotic solvent and water.

Abstract: The present disclosure is drawn to material sets for 3D printing and methods of 3D printing. The material set can include a coalescent an organic-soluble near-infrared dye having a peak absorption wavelength from 800 nm to 1400 nm. The coalescent ink can also include water and an organic co-solvent. The material set can also include a particulate polymer formulated to coalesce when contacted by the coalescent ink and irradiated by a near-infrared energy having the peak absorption wavelength.

Abstract: To additively manufacture a 3D object, a layer of material is deposited onto a receiving surface. Droplets are selective deposited onto first portions of the layer with at least some droplets including at least a first color agent. A gas discharge illuminant selectively induces a first amount of heating in the first portions of the layer substantially greater than a second amount of heating in second portions of the layer omitting the first color agent.

Abstract: Example described herein include a three-dimensional printer a three-dimensional printing device that includes a fusible material applicator to apply a layer of fusible material, a inhibiting material applicator to apply a patterned layer of inhibiting material to establish exposed regions of the layer of fusible material and blocked regions of the layer of fusible material based on information corresponding to a three-dimensional model, and a photonic energy emitter to apply photonic energy to fuse the exposed regions of the layer of fusible material.