An image forming apparatus includes a transport unit, a transfer unit and a support unit. The transport unit transports a recording medium. The transfer unit transfers an image formed with particles onto an image formation surface of the recording medium transported by the transport unit by an electric field formed between the transfer unit and the image formation surface by making contact with the image formation surface. The support unit supports the recording medium, is transported to the transfer unit together with the recording medium by the transport unit, and is not directly conductive with the transfer unit.

A three-dimensional (3-D) printer includes build and support material development stations positioned to transfer layers of build and support materials to an intermediate transfer surface. A platen having a flat surface is positioned to contact the intermediate transfer surface. The intermediate transfer surface transfers a layer of the build and support materials to the flat surface of the platen as the platen contacts one of the layers on the intermediate transfer surface. A dispenser is positioned to deposit a leveling material on the layer on the platen, and a mechanical planer is positioned to contact and level the leveling material on the layer on the platen to make the top of the leveling material parallel to the flat surface of the platen.

A method for printing a three-dimensional part and a support structure with an electrophotography-based additive manufacturing system. The method includes developing a support layer of the support structure from a soluble support material with a first electrophotography engine, and transferring the developed support layer from the first electrophotography engine to a transfer medium. The method also includes developing a part layer of the three-dimensional part from an ABS part material with a second electrophotography engine, and transferring the developed part layer from the second electrophotography engine to the transfer medium. The method further includes moving the attracted part and support layers to a layer transfusion assembly with the transfer medium, and transfusing the moved part and support layers together to previously-printed layers with the layer transfusion assembly.

A method of printing three-dimensional parts with an electrophotography-based additive manufacturing system, with a part material including a composition having an engineering-grade 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 image forming apparatus includes an image carrier, an endless intermediate transfer belt, a primary transfer member, a secondary transfer member, a displacement amount detecting device, and a control unit. The displacement amount detecting device detects displacement amounts of a reference image in a main-scanning direction and a sub-scanning direction. The reference image is formed on the intermediate transfer belt. The displacement amount detecting device includes a density detecting sensor and a surface potential sensor. The density detecting sensor detects a print density of the reference image formed on the intermediate transfer belt. The surface potential sensor detects a surface potential of the reference image. The displacement amount detecting device simultaneously detects the identical reference image using the density detecting sensor and the surface potential sensor to ensure simultaneous detections of displacement amounts in the main-scanning direction and the sub-scanning direction.

In 3-D printing a platen moves toward an intermediate transfer belt (ITB) to have a sheet positioned on the platen contact the ITB to electrostatically transfer a layer of different materials to the sheet, and then the platen moves to a heater to join the layer to the sheet. This processing is repeated to have the sheet repeatedly contact the ITB (with intervening heating at the heater) to successively form layers of the materials on the sheet. The sheet having the layers thereon moves to a rinsing station, where a liquid is applied to dissolve the sheet and leave a freestanding stack of the layers. The freestanding stack is fed to a platform to successively form a 3-D structure of freestanding stacks of the layers. Light and/or heat are applied to the 3-D structure to bond the freestanding stacks to one another on the platform.

A method for forming a scratchable image includes pressure-fixing a masking pressure toner onto a base image on a substrate to form a masking layer.

In 3-D printing a platen moves toward an intermediate transfer belt (ITB) to have a sheet positioned on the platen contact the ITB to electrostatically transfer a layer of different materials to the sheet, and then the platen moves to a stabilization station to join the layer to the sheet. This processing is repeated to have the sheet repeatedly contact the ITB (with intervening stabilization at the stabilization station) to successively form layers of the materials on the sheet. The freestanding stack is fed to a platform to successively form a 3-D structure of freestanding stacks of the layers. Heat and/or pressure and/or light are applied to the 3-D structure to bond the freestanding stacks to one another through the sheets of collapsible media on the platform.

A support material for printing a support structure with an electrophotography-based additive manufacturing system, the support material including a composition having a charge control agent and a thermoplastic copolymer having aromatic groups, (meth)acrylate-based ester groups, carboxylic acid groups, and anhydride groups, with a high anhydride conversion. The composition is provided in a powder form having a controlled particle size, and the support material is configured for use in the electrophotography-based additive manufacturing system having a layer transfusion assembly for printing the support structure in a layer-by-layer manner, and is at least partially soluble in an aqueous solution.

A method for printing a three-dimensional part with an additive manufacturing system includes providing a bitslice stack having a plurality of bitslices and printing a plurality of successive layers of the three-dimensional part with the additive manufacturing system based on the bitslices in the bitslice stack. The method includes measuring density of the three-dimensional part under construction near an intermediate build surface after one or more of the successive layers are printed. The method includes determining differences across the intermediate build surface of the measured density to a targeted density to identify one or more density error regions across the intermediate build surface, wherein the density error regions comprise low density regions, and modifying the bitslice stack to compensate for the one or more density error regions.