Abstract: In an example method for forming three-dimensional (3D) printed electronic parts, a build material is applied. An electronic agent is selectively applied in a plurality of passes on a portion of the build material. A fusing agent is also selectively applied on the portion of the build material. The build material is exposed to radiation in a plurality of heating events. During at least one of the plurality of heating events, the portion of the build material in contact with the fusing agent fuses to form a region of a layer. The region of the layer exhibits an electronic property. An order of the plurality of passes, the selective application of the fusing agent, and the plurality of heating events is controlled to control a mechanical property of the layer and the electronic property of the region.

Abstract: An example provides a method for forming an apparatus including a substrate imprinted with a pattern for forming isolated device regions. A method may include imprinting an unpatterned area of a substrate with a pattern to form a patterned substrate having a plurality of recessed regions at a first level and a plurality of elevated regions at a second level, and depositing a first layer of conductive material over the patterned substrate with a plurality of breaks to form a plurality of bottom electrodes. The method may include depositing a layer of an active stack, with a second layer of conductive material, over the plurality of bottom electrodes to form a plurality of devices on the plurality of recessed regions isolated from each other by the plurality of elevated regions.

Abstract: An example of a fusing agent includes a metal bis(dithiolene) complex, a thiol surfactant, a polar aprotic solvent, and a balance of water. In an example of a method of making the fusing agent, the metal bis(dithiolene) complex is exposed to an aqueous solution including a reducing agent and a thiol surfactant to form a reduced metal bis(dithiolene) complex and to dissolve the reduced metal bis(dithiolene) complex in the aqueous solution. The aqueous solution is incorporated into a vehicle including a water soluble organic solvent and an additive selected from the group consisting of an emulsifier, a surface tension reduction agent, a wetting agent, a scale inhibitor, an anti-deceleration agent, a chelating agent, an antimicrobial agent, and a combination thereof. The fusing agent may be utilized in a three-dimensional printing method and/or incorporated into a three-dimensional printing system.

Abstract: In an example of a three-dimensional (3D) printing method, a polymeric or polymeric composite build material is applied. A fusing agent is selectively applied on at least a portion of the polymeric or polymeric composite build material. The fusing agent includes a discolorable near-infrared absorbing dye, a thiol surfactant, a reducing agent, and a balance of water. Near-infrared radiation is applied to the polymeric or polymeric composite build material at a condition that maintains a temperature of the selectively applied fusing agent below a decomposition temperature of the fusing agent and that allows the discolorable near-infrared absorbing dye to harvest near-infrared radiation energy, in order to fuse the portion of the polymeric or polymeric composite build material in contact with the fusing agent to form a layer and to initiate discoloration of the discolorable near-infrared absorbing dye in the layer.

Abstract: In some examples, a request to print a first three-dimensional (3D) part is received. In response to determining that the first 3D part is not similar to any 3D part referred to by an information base, a representation of the first 3D part is extracted, an indication to conduct an operation to produce a design rule for the first 3D part is sent. In response to determining that the first 3D part is similar to a matching 3D part referred to by the information base, a design rule for the matching 3D part is retrieved to print the first 3D part, where the design rule for the matching 3D part specifies a dependency of a property of the matching 3D part on an aspect associated with printing the matching 3D part.

Abstract: In some examples, a distribution of values of a property of a given layer to be printed as part of three-dimensional (3D) printing is predicted, wherein the predicting is based on a distribution of values of the property in a previous layer that has been printed as part of the 3D printing. 3D printing of an object is controlled based on the predicted distribution of values of the property of the given layer.

Abstract: In one example, an additive manufacturing process includes: making an object slice by slice, including dispensing a first quantity of each of multiple liquid functional agents on to a layer of fusable build material and then irradiating the layer of build material; while making the object, identifying a deviant region in a slice; and dispensing a second quantity different from the first quantity of at least one of the functional agents into a location corresponding to the deviant region.

Abstract: Examples include an apparatus for generating a three-dimensional object. The apparatus comprises at least one energy source, at least one build layer temperature sensor, and a controller. The controller is to control the at least one energy source to pre-fuse a portion of a build layer in a build area when a build layer temperature is less than a first temperature threshold. The controller is further to, after pre-fusing the portion of the build layer, control the at least one energy source to fuse the portion of the build layer in the build area when the build layer temperature is less than a second threshold.

Abstract: An example of a fusing agent includes a tetraphenyldiamine-based dye, alkyldiphenyloxide disulfonate, 1-methyl-2-pyrrolidone, and a balance of water. The fusing agent excludes a strong reducing species. The fusing agent may be incorporated into a three-dimensional printing method or a three-dimensional printing system. In an example of the three-dimensional printing method, a polymeric or polymeric composite build material is applied. The fusing agent is selectively applied on at least a portion of the polymeric or polymeric composite build material. The polymeric or polymeric composite build material is exposed to electromagnetic radiation to fuse the portion of the polymeric or polymeric composite build material in contact with the fusing agent to form a layer.

Abstract: The present disclosure is drawn to a particulate build material for three-dimensional printing. The particulate build material can include a plurality of particulates, wherein individual particulates include a particulate core having a photosensitive coating applied to a surface of the particulate core. The particulate core includes a metal, a ceramic, or both a metal and a ceramic. The photosensitive coating includes a polymer having a photosensitive agent suspended or attached therein.

Abstract: The present disclosure is drawn material sets, coalescent fluids, and 3-dimensional printing systems. An example material set can include an amorphous polymer powder having an average particle size from 1 micron to 300 microns, and a coalescent fluid including a viscosity reducing agent.

Abstract: According to an example, a three-dimensional (3D) printer may include a first delivery device to selectively deposit a fusing agent onto a layer of build materials and a second delivery device to deposit coolant droplets at tuned drop weights onto the layer of build materials. The 3D printer may also include a controller to control the second delivery device to selectively deposit the coolant droplets at the tuned drop weights onto selected areas of the build material layer, in which the drop weights of the selectively deposited coolant droplets are tuned to provide a thermal balance between multiple areas of the build material layer during application of fusing radiation onto the build material layer.

Abstract: In an example of a three-dimensional (3D) printing method, a polymeric build material is applied. A fusing agent is selectively applied on at least a portion of the polymeric build material. A mechanical tailoring agent is selectively applied on at least a region of the portion. The polymeric build material is exposed to radiation, thereby fusing the at least the portion of the polymeric build material in contact with the fusing agent to form a layer. The mechanical tailoring agent forms a composite layer in the at least the region, and the composite layer has a different mechanical property than that of an area of the layer not in contact with the mechanical tailoring agent.

Abstract: In an example of a three-dimensional (3D) printing method, a crystalline or semi-crystalline build material is applied. A temperature of the crystalline or semi-crystalline build material is maintained within 100° C. below a melting point of the crystalline or semi-crystalline build material. A melt flow property reduction agent is applied to at least a portion of the crystalline or semi-crystalline build material, and the at least the portion of the crystalline or semi-crystalline build material in contact with the melt flow property reduction agent melts or coalesces at the temperature.

Abstract: According to an example, a three-dimensional (3D) printer may include a first delivery device to selectively deposit first liquid droplets onto a layer of build materials, in which the first liquid has a fusing radiation absorption property. The 3D printer may also include a fusing radiation generator to selectively emit fusing radiation at multiple ranges of wavelengths and at selected locations to selectively fuse the build materials and a controller to tune a range of wavelengths at which the fusing radiation generator is to emit fusing radiation based upon the fusing radiation absorbing property of the deposited first liquid, to determine the selected locations at which the fusing radiation at the tuned range of wavelengths is to be emitted, and to control the fusing radiation generator to selectively emit fusing radiation at the tuned range of wavelengths and onto the selected locations.

Abstract: Compositions and methods for 3D printing are described herein. In an example, a composition for 3D printing can comprise a build material comprising at least one polymer and at least one first electron donor compound; and a fusing agent comprising (i) a metal bis(dithiolene) complex, (ii) at least one surfactant, at least one second electron donor compound, or combinations thereof, (iii) a polar aprotic solvent, and (iv) water. The at least one first electron donor compound and the at least one second electron donor compound can be the same or different.

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: 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: The present disclosure is drawn to coalescent inks and material sets, such as for 3D printing. In one example, the coalescent ink can include a conjugated polymer, a colorant imparting a visible color to the coalescent ink, and an ink vehicle comprising a high boiling point co-solvent having a boiling point of 250° C. or greater. The high boiling point co-solvent can be present in an amount from about 1 wt % to about 4 wt % with respect to the coalescent ink.

Abstract: An agent distributor may be to selectively deliver agent at a first contone density and at a second contone density different from the first contone density respectively onto an interior portion and a surface portion of successive layers of build material in respective first and second patterns in accordance with data representing a three-dimensional object to be generated, so that the build material is to solidify to form slices of the three-dimensional object in accordance with the first and second patterns, and so that the three-dimensional object is to achieve a target surface roughness as a result of the second contone density of the second pattern.