Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition, an epoxy agent to be applied to at least a portion of the build material composition during 3D printing, and a fusing agent to be applied to the at least the portion of the build material composition during 3D printing. The build material composition includes a polyamide having an amino functional group. The epoxy agent includes an epoxy having an epoxide functional group to react with the amino functional group of the polyamide in the at least the portion. The fusing agent includes an energy absorber.

Abstract: In an example, a three-dimensional (3D) printed part comprises a plurality of fused build material layers including exterior layers and interior layers. At least some of the interior layers include a composite portion having a miscible solid physically bonded to an amide functionality or an amine functionality of the build material. The miscible solid is a solid at a room temperature ranging from about 18° C. to about 25° C.

Abstract: An example of a three-dimensional (3D) printing kit includes a build material composition, an epoxy agent to be applied to at least a portion of the build material composition during 3D printing, and a fusing agent to be applied to the at least the portion of the build material composition during 3D printing. The build material composition includes a polyamide having an amino functional group. The epoxy agent includes an epoxy having an epoxide functional group to react with the amino functional group of the polyamide in the at least the portion. The fusing agent includes an energy absorber.

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: In an example, a three-dimensional (3D) printed part comprises a plurality of fused build material layers including exterior layers and interior layers. At least some of the interior layers include a composite portion having a miscible solid physically bonded to an amide functionality or an amine functionality of the build material. The miscible solid is a solid at a room temperature ranging from about 18° C. to about 25° C.

Abstract: The present disclosure is drawn to multi-fluid kits for three-dimensional to printing, three-dimensional printing kits, and methods of making three-dimensional printed articles. In one example, a multi-fluid kit for three-dimensional printing can include a fusing agent, a first reactive agent, and a second reactive agent. The fusing agent can include water and a radiation absorber. The first reactive agent can include a first liquid vehicle and an epoxy compound having multiple epoxide groups. The second reactive agent can include a second liquid vehicle and an amine compound having multiple amino groups.

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 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, 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: The present disclosure is drawn to multi-fluid kits for three-dimensional to printing, three-dimensional printing kits, and methods of making three-dimensional printed articles. In one example, a multi-fluid kit for three-dimensional printing can include a fusing agent, a first reactive agent, and a second reactive agent. The fusing agent can include water and a radiation absorber. The first reactive agent can include a first liquid vehicle and an epoxy compound having multiple epoxide groups. The second reactive agent can include a second liquid vehicle and an amine compound having multiple amino groups.

Abstract: In an example, a method includes operating, by a processor, on object model data. The object model data describes at least part of an object to be generated in additive manufacturing. The method also includes determining, by a processor, pattern data. The pattern data comprising areas of variable reflectance intended to be formed on a portion of the object. The method includes determining, by a processor, object generation instructions to apply a fusing agent to at least part of a layer of build material corresponding to the portion of the object in a density corresponding to the reflectance of the generated pattern data.

Abstract: In one example in accordance with the present disclosure, a method is described. The example method includes forming a lattice anchor with a build material in a powder bed of a three-dimensional (3D) printing system. The example method also includes forming a 3D object with the build material attached to the lattice anchor.

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: According to an example, a three-dimensional (3D) printer may include a delivery device to deposit a light absorbing agent onto selected areas of a layer of build material particles, in which the light absorbing agent absorbs light having wavelengths that are around the ultraviolet wavelength range. The 3D printer may also include a light source to apply light onto the selectively deposited light absorbing agent and the layer of the build material particles, in which the light absorbing agent absorbs light around the ultraviolet wavelength range from the applied light and becomes heated to a temperature that causes the build material particles upon which the light absorbing agent has been deposited to melt and to fuse together following cessation of the application of the light.

Abstract: The present disclosure relates to a method of manufacturing a 3D printed object. The method comprises selectively applying a fusing agent onto powder bed material; and exposing at least part of the powder bed material to radiation to fuse at least part of the powder bed material to form a layer of the 3D printed object. The fusing agent and/or a detailing agent is selectively applied to the powder bed material in a predetermined arrangement to form a porous region in the 3D printed object. The 3D printed object is then treated with a modifying agent, such that the modifying agent at least partially penetrates the porous region of the 3D printed object.

Abstract: The present disclosure is drawn to multi-fluid kits for three-dimensional printing, three-dimensional printing kits, and methods of making three-dimensional printed articles. In one example, a multi-fluid kit for three-dimensional printing can include a fusing agent, a first reactive agent, and a second reactive agent. The fusing agent can include water and a radiation absorber. The first reactive agent can include a first liquid vehicle and an epoxy compound having multiple epoxide groups. The second reactive agent can include a second liquid vehicle and an amine compound having multiple amino groups.

Abstract: A three-dimensional printing system can include polymeric build material and jettable fluid(s). The polymeric build material can have an average particle size from 20 ?m to 150 ?m, a first melt viscosity, and a melting temperature from 75° C. to 350° C. In one example, the jettable fluid can include water, from 0.1 wt % to 10 wt % of electromagnetic radiation absorber, and from 10 wt % to 35 wt % of an organic solvent plasticizer. Contacting a first portion of a layer of the polymeric build material with the jettable fluid can provide an organic solvent plasticizer loading from 2 wt % to 10 wt % based on the polymeric build material content. The first melt viscosity of the polymeric build material at the first portion can be reduced and the melting temperature of the polymeric build material at the first portion can be decreased by 3° C. to 15° C.

Abstract: The present disclosure relates to a three-dimensional printing kit comprising: a powder bed material comprising polymer particles; a fusing agent comprising a radiation absorber and a liquid carrier; and a magnetic marking agent comprising magnetic nanoparticles, a humectant and a liquid carrier, wherein the concentration of magnetic nanoparticles is 5 to 70 weight % based on the total weight of the magnetic agent. The present disclosure also relates to a method of three-dimensional (3D) printing a 3D printed object. The method comprises: selectively applying a magnetic marking agent onto powder bed material, wherein the powder bed material comprises polymer particles, and wherein the magnetic marking agent comprises magnetic nanoparticles and a liquid carrier; selectively fusing the powder bed material, such that the magnetic nanoparticles are incorporated in the 3D printed object in a predetermined arrangement that forms a detectable marker in the 3D printed object.

Abstract: According to an example, a three-dimensional (3D) printer may include a delivery device to deposit a light absorbing agent onto selected areas of a layer of build material particles, in which the light absorbing agent absorbs light having wavelengths that are around the ultraviolet wavelength range. The 3D printer may also include a light source to apply light onto the selectively deposited light absorbing agent and the layer of the build material particles, in which the light absorbing agent absorbs light around the ultraviolet wavelength range from the applied light and becomes heated to a temperature that causes the build material particles upon which the light absorbing agent has been deposited to melt and to fuse together following cessation of the application of the light.

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.