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 polyamide having: an avalanche angle ranging from about 35 degrees to about 55 degrees; a break energy ranging from about 25 kJ/kg to about 57 kJ/kg; and an avalanche energy ranging from about 7 kJ/kg to about 22 kJ/kg. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the polyamide in the at least the portion.

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 polyamide having a melt enthalpy ranging from greater than 5 J/g to less than 150 J/g. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the polyamide in the at least the portion. The fusing agent is a core fusing agent and the energy absorber has absorption at least at wavelengths ranging from 400 nm to 780 nm; or the fusing agent is a primer fusing agent and the energy absorber is a plasmonic resonance absorber having absorption at wavelengths ranging from 800 nm to 4000 nm and having transparency at wavelengths ranging from 400 nm to 780 nm.

Abstract: In an example of a three-dimensional (3D) printing method, a build material (consisting of an inorganic particle and a polymer attached thereto) is applied. The polymer is a continuous coating having a thickness from about 3 nm to about 1500 nm, or nano-beads having an average diameter from about 3 nm to about 1500 nm. The build material is heated to a temperature from about 5° C. to about 50° C. below the polymer's melting point. A coalescent dispersion (including a coalescent agent and inorganic nanoparticles) is selectively applied on a portion of the build material, and the applied build material and coalescent dispersion are exposed to electromagnetic radiation. The coalescent dispersion absorbs the electromagnetic radiation and heats up the portion of the build material in contact therewith to fuse the portion of the build material in contact with the coalescent dispersion and to form a layer of a 3D object.

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 thermoplastic elastomer having: an avalanche angle ranging from about 49 degrees to about 59 degrees; a break energy ranging from about 55 kJ/kg to about 78 kJ/kg; and an avalanche energy ranging from about 10 kJ/kg to about 27 kJ/kg. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the thermoplastic elastomer in the at least the portion.

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 polyamide having: an avalanche angle ranging from about 35 degrees to about 55 degrees; a break energy ranging from about 25 kJ/kg to about 57 kJ/kg; and an avalanche energy ranging from about 7 kJ/kg to about 22 kJ/kg. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the polyamide in the at least the portion.

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 thermoplastic elastomer particles, wherein at least 70% of the thermoplastic elastomer particles, based on a number distribution, have an aspect ratio ranging from 0.75 to 1. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the thermoplastic elastomer particles in the at least the portion.

Abstract: An example of a three-dimensional (3D) printing composition 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 one of: (i) a thermoplastic elastomer having a flow parameter characterized by a consolidation resistance value ranging from about 8 to about 30, and a tap density characterized by an n1/2 value ranging from 5 taps to 30 taps; or (ii) a polyamide-like material having a flow parameter characterized by a consolidation resistance value ranging from about 75 to about 120, and a tap density characterized by an n1/2 value ranging from 5 taps to 30 taps. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the thermoplastic elastomer or the polyamide-like material in the at least the portion.

Abstract: A coalescing agent for three-dimensional (3D) printing includes a co-solvent, a surfactant having a hydrophilic lipophilic balance (HLB) value that is less than 10, a carbon black pigment, a polymeric dispersant, and a balance of water. The co-solvent is present in an amount ranging from about 15 wt % to about 30 wt % of a total wt % of the coalescing agent. The surfactant is present in an amount ranging from about 0.5 wt % to about 1.4 wt % of the total wt % of the coalescing agent. The carbon black pigment is present in an amount ranging from about 3.0 wt % to about 6.0 wt % of the total wt % of the coalescing agent. The polymeric dispersant has a weight average molecular weight ranging from about 12,000 to about 20,000.

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 thermoplastic elastomer having a melt enthalpy ranging from greater than 5 J/g to about 177 J/g. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the thermoplastic elastomer in the at least the portion. The fusing agent is a core fusing agent and the energy absorber has absorption at least at wavelengths ranging from 400 nm to 780 nm; or the fusing agent is a primer fusing agent and the energy absorber is a plasmonic resonance absorber having absorption at wavelengths ranging from 800 nm to 4000 nm and having transparency at wavelengths ranging from 400 nm to 780 nm.

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 semi-crystalline or amorphous thermoplastic polymer having a predicted total dimension change during 3D printing ranging from about ?4% to about 9%. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the semi-crystalline or amorphous thermoplastic polymer in the at least the portion. The fusing agent is a core fusing agent and the energy absorber has absorption at least at wavelengths ranging from 400 nm to 780 nm; or the fusing agent is a primer fusing agent and the energy absorber has absorption at wavelengths ranging from 800 nm to 4000 nm and has transparency at wavelengths ranging from 400 nm to 780 nm.

Abstract: The present disclosure is drawn to material sets and 3-dimensional printing systems that include a fusing agent. One example of a material set can include a fusing agent and a detailing agent. The fusing agent can include water, a carbon black pigment, and a water-soluble co-solvent in an amount from 20 wt % to 60 wt %. The detailing agent can include water and a black dye. In another example, a material set can include a fusing agent and a thermoplastic polymer powder.

Abstract: The present disclosure is drawn to a composite particulate build material, including 92 wt % to 99.5 wt % polymeric particles having an average size from 10 ?m to 150 ?m and an average aspect ratio of less than 2:1, The composite particulate build material further includes from 0.5 wt % to 8 wt % reinforcing particles having an average size of 0.1 ?m to 20 ?m and an average aspect ratio of 3:1 to 100:1 applied to a surface of the polymeric particles.

Abstract: The present disclosure is drawn to material sets and 3-dimensional printing systems that include a fusing agent. One example of a material set can include a fusing agent and a detailing agent. The fusing agent can include water, a carbon black pigment, and a water-soluble co-solvent in an amount from 20 wt % to 60 wt %. The detailing agent can include water and a black dye. In another example, a material set can include a fusing agent and a thermoplastic polymer powder.

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 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.

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 semi-crystalline thermoplastic polymer having a surface energy density greater than 41 mN/m. The fusing agent includes an energy absorber to absorb electromagnetic radiation to coalesce the semi-crystalline thermoplastic polymer in the at least the portion.

Abstract: The present disclosure relates to a composition for printing a three-dimensional object. The composition comprises composite particles comprising a thermoplastic 5 polymer and a colour-masking pigment. The colour-masking pigment is encapsulated by the thermoplastic polymer and is present in an amount of from about 1.5 to less than about 6 wt % of the total weight of the composite particles.

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: 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.