Abstract: The present disclosure describes 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 and a second fluid agent. The fusing agent can include water and a radiation absorber. The radiation absorber can absorb radiation energy and convert the radiation energy to heat. The fusing agent or the second fluid agent can include a water-soluble or water-dispersible dihydrazide antioxidant.

Abstract: A polyol stiffening additive in a powder bed material for three-dimensional (3D) printing is disclosed herein. In an example, the 3D powder bed material includes an elastomeric build material and a polyol stiffening additive having 3 to 7 carbon atoms that is about 2 weight percent to about 20 weight percent of a total weight of the 3D powder bed material.

Abstract: An example of a three-dimensional (3D) build material composition includes from about 70 wt % to about 95 wt % of polyamide particles, based upon a total weight of the build material composition; and from about 5 wt % to about 30 wt % of biodegradable polyester filler particles, based upon the total weight of the build material composition. The biodegradable polyester filler particles are present in the build material composition without any additional filler particles.

Abstract: An example of a kit for 3D printing 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 of the kit includes a polyamide 6,13 material, a phosphorus-containing antioxidant, and a sulfur-containing antioxidant, or a polyamide 6 material, the sulfur-containing antioxidant, and a phenolic antioxidant. The fusing agent includes a radiation absorber to absorb radiation to melt or fuse the build material composition in the at least the portion.

Abstract: This disclosure describes hydrogel three-dimensional printing kits, methods of three-dimensional printing hydrogels, and hydrogel three-dimensional printing systems. In one example, a hydrogel three-dimensional printing kit can include a particulate build material and an aqueous agent. The particulate build material can include from about 90 wt % to 100 wt % of a mixture of a powdered polyhydroxylated swellable polymer dry blended with powdered water-soluble crosslinker that is reactive with hydroxyl groups of the polyhydroxylated swellable polymer to crosslink the polyhydroxylated swellable polymer. The aqueous agent can include water and an organic co-solvent, and the aqueous agent may not include the crosslinker.

Abstract: An example of a kit for 3D printing 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 of the kit includes a polyamide 6,13 material, a phosphorus-containing antioxidant, and a sulfur-containing antioxidant, or a polyamide 6 material, the sulfur-containing antioxidant, and a phenolic antioxidant. The fusing agent includes a radiation absorber to absorb radiation to melt or fuse the build material composition in the at least the portion.

Abstract: A polyol stiffening additive in a powder bed material for three-dimensional (3D) printing is disclosed herein. In an example, the 3D powder bed material includes an elastomeric build material and a polyol stiffening additive having 3 to 7 carbon atoms that is about 2 weight percent to about 20 weight percent of a total weight of the 3D powder bed material.

Abstract: The present disclosure describes 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 and a second fluid agent. The fusing agent can include water and a radiation absorber. The radiation absorber can absorb radiation energy and convert the radiation energy to heat. The fusing agent or the second fluid agent can include a water-soluble or water-dispersible dihydrazide antioxidant.

Abstract: An example of a kit for three-dimensional printing includes a build material composition and a crosslinking agent to be applied to at least a portion of the build material composition during 3D printing. The build material composition of the kit includes an amorphous polymeric material. The crosslinking composition of the kit includes a crosslinking agent to crosslink with the amorphous polymeric material in the at least the portion, to yield a crosslinked polymer network.

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: A three-dimensional printed object can include a fused polyamide body having electromagnetic radiation absorber embedded as particles within the fused polyamide body, and the three-dimensional printed object can further include residual benzyl alcohol soaked into a surface of the polyamide body.

Abstract: This disclosure describes three-dimensional printing kits, methods, and systems for three-dimensional printing with triethylene glycol fusing agents. In one example, a three-dimensional printing kit can include a powder bed material including polymer particles and a fusing agent to selectively apply to the powder bed material. The fusing agent can include water, a radiation absorber, and triethylene glycol in an amount from about 20 wt % to about 35 wt %. The radiation absorber can absorb radiation energy and convert the radiation energy to heat to fuse the powder bed material.

Abstract: This disclosure describes three-dimensional printing kits, methods, and systems for three-dimensional printing with triethylene glycol fusing agents. In one example, a three-dimensional printing kit can include a powder bed material including polymer particles and a fusing agent to selectively apply to the powder bed material. The fusing agent can include water, a radiation absorber, and triethylene glycol in an amount from about 20 wt % to about 35 wt %. The radiation absorber can absorb radiation energy and convert the radiation energy to heat to fuse the powder bed material.

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: Compositions including polyamides and methods of employing compositions including polyamides are described herein. For instance, composition for three-dimensional (3D) printing can include a polymer build material comprising of at least two polyamides including a first polyamide and a second polyamide, where the first polyamide is present in an amount ranging of from about 95% to about 99% of a total weight of the polymer build material and where the second polyamide is present in an amount ranging of from about 1% to about 5% of the total weight of the polymer build material.

Abstract: Compositions including polyamides and methods of employing compositions including polyamides are described herein. For instance, composition for three-dimensional (3D) printing can include a polymer build material comprising of at least two polyamides including a first polyamide and a second polyamide, where the first polyamide is present in an amount ranging of from about 95% to about 99% of a total weight of the polymer build material and where the second polyamide is present in an amount ranging of from about 1% to about 5% of the total weight of the polymer build material.

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 a three-dimensional (3D) build material composition includes from about 70 wt % to about 95 wt % of polyamide particles, based upon a total weight of the build material composition; and from about 5 wt % to about 30 wt % of biodegradable polyester filler particles, based upon the total weight of the build material composition. The biodegradable polyester filler particles are present in the build material composition without any additional filler particles.

Abstract: Hydrogel three-dimensional printing kits, methods of three-dimensional printing and three-dimensional printed hydro-gels are described. In one example, a three-dimensional printing kit can comprise a particulate build material, a crosslinking agent and a structural modifier. The particulate build material may comprise a polyhydroxylated polymer having hydroxyl groups. The crosslinking gent is for crosslinking the polyhydroxylated polymer by a reaction with the hydroxyl groups. The structural modifier can have a plurality of functional groups for forming a network within the hydrogel, and where the structural modifier may have a reactivity that is chemically orthogonal to the reaction with the hydroxyl groups for crosslinking the polyhydroxylated polymer.

Abstract: The present disclosure relates to a composition for printing a three-dimensional object. The composition comprises composite particles comprising a thermoplastic 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.