3-D printing transfers build material and support from an intermediate transfer belt (ITB) to a platen. The build material is the same as the support material, except that the build material includes a photoinitiator and the support material does not. The platen moves to make contact with the ITB, and the ITB transfers successive layers of build material and support material each time the platen contacts the ITB. The platen and a portion of the ITB that is adjacent the platen are heated prior to the platen contacting the ITB, and the same is exposed so as to crosslink polymers of build material, without crosslinking polymers of support material. The polymers of build material being crosslinked and the polymers of support material not being crosslinked makes the support material selectively soluble in a solvent.

A 3-D printer includes a development station positioned to electrostatically transfer layers of material to an intermediate transfer surface, and a transfuse station adjacent the intermediate transfer surface. The transfuse station is positioned to receive the layers as the intermediate transfer surface moves past the transfuse station. Also, a platen is included that moves relative to the intermediate transfer surface. The intermediate transfer surface transfers a layer of the material to the platen each time the platen contacts one of the layers on the intermediate transfer surface at the transfuse station to successively form a freestanding stack of the layers on the platen. A curing station is positioned to apply ultraviolet light to each layer, after each layer is transferred from the transfuse station to the platen. The curing station selectively applies the ultraviolet light to crosslink polymers only in a portion of the material within the layer.

Layers of build and support material on an intermediate transfer surface are moved past a transfuse station and a platen moves relative to the intermediate transfer surface to contact the platen to one of the layers on the intermediate transfer surface. The intermediate transfer surface transfers a layer of the build material and the support material to the platen each time the platen contacts the layers on the intermediate transfer surface at the transfuse station to successively form a freestanding stack of the layers of build and support material on the platen. The build material has a higher melting temperature than the support material. A support material removal station heats the stack to a temperature above the melting temperature of the support material, but below the melting temperature of the build material, to melt the support material, but leave a 3-D structure made of only the build material.

A 3-D printer includes a development station positioned to electrostatically transfer layers of material to an intermediate transfer surface, and a transfer station adjacent the intermediate transfer surface. The transfer station is positioned to receive the layers as the intermediate transfer surface moves past the transfer station. Also, a platen is included that moves relative to the intermediate transfer surface. The intermediate transfer surface transfers a layer of the material to the platen each time the platen contacts one of the layers on the intermediate transfer surface at the transfer station to successively form a freestanding stack of the layers on the platen. A fusing station is positioned to apply light to each layer, after each layer is transferred from the transfer station to the platen. The fusing station selectively applies the light to sinter a portion of the material within the layer.

An additive manufacturing method produces a 3D part utilizes electrophotography-based additive manufacturing and molding processes. A layered structure having a cavity is printed on a build platform using at least one electrophotographic (EP) engine to develop imaged layers of powder material, and a transfusion assembly to stack and fuse the imaged layers on the build platform. Molding material is deposited into the cavity as the layered structure is printed, using a deposition unit. The molding material solidifies to form at least a portion of the 3D part, which may also include portions formed from imaged powder material.

A part material for printing three-dimensional parts with an electrophotography-based additive manufacturing system, the part material including a composition having a semi-crystalline thermoplastic material and a charge control agent. The part material is provided in a powder form having a controlled particle size, and is configured for use in the electrophotography-based additive manufacturing system having a layer transfusion assembly for printing the three-dimensional parts in a layer-by-layer manner.

An additive manufacturing system comprising a transfer medium configured to receive the layers from a imaging engine, a heater configured to heat the layers on the transfer medium, and a layer transfusion assembly that includes a build platform, and is configured to transfuse the heated layers onto the build platform in a layer-by-layer manner to print a three-dimensional part.

A platen assembly for use in an additive manufacturing system, which includes a platen plate that is preferably secured to a gantry mechanism of the additive manufacturing system, and having a top surface, and one or more magnets secured to the platen plate and configured to generate one or more magnetic fields at the top surface of the platen plate. The platen gantry is configured to magnetically couple interchangeable and replaceable build sheets to the top surface of the platen plate due to the one or more generated magnetic fields, and where the magnetically-coupled build sheets are configured to receive the printed layers from the printing mechanism.

An additive manufacturing system comprising a transfer medium configured to receive the layers from a imaging engine, a heater configured to heat the layers on the transfer medium, and a layer transfusion assembly that includes a build platform, and is configured to transfuse the heated layers onto the build platform in a layer-by-layer manner to print a three-dimensional part.

3-D printers include a transfuse station having at least one roller on one side of the ITB supporting the ITB, and a transmission device on the same side of the ITB. A platen is included that moves relative to the ITB. The ITB electrostatically transfers a layer made up of the different color build materials and the support material to the platen each time the platen contacts the other side of the ITB at the transfuse station (the side of the ITB opposite the transfuse station roller and transmission device) using vibration and charge devices; and this successively forms multiple layers of the build materials and the support material on the platen.