The invention relates to a system for producing a three-dimensional object by solidifying layer by layer a material that can be solidified under the effect of radiation. The system comprises a device for releasing a material layer of the solidifiable material that has solidified on a carrier defining a reference surface from the carrier. The device comprises a flexible elastic release element. The release element is arranged between the carrier and the material layer and can be detached nondestructively from the carrier. The system also comprises a fluid introduction device for introducing a release fluid between the carrier and the release element. The reference surface is curved in a way deviating from a plane.

A 3D part and a support structure is printed using an electrophotography-based additive manufacturing system. A support layer of the support structure is developed with a first electrophotography engine using a support material and transferred to a transfer medium. A large-particle part layer corresponding to a first portion of the 3D part is developed with a second electrophotography engine using a first part material and transferred to a transfer medium, and a plurality of small-particle part layers corresponding to a second portion of the 3D part are developed with one or more additional electrophotography engines using a second part material and transferred to a transfer medium. An average size of the first part material particles is at least two times that of the second part material particles. The transferred support layer, large-particle part layer and small-particle part layers are transfused to previously-printed layers using a layer transfusion assembly.

An apparatus for producing a three-dimensional object includes a support assembly having a build platform, a track extending through a build area, and a deposition mechanism mounted on the track and configured for producing the three-dimensional object in a layer-by-layer technique. The deposition mechanism includes a carriage moveable along the track, a supply of a flowable material mounted on the carriage, a roller in communication with the flowable material, where the roller is rotatably mounted on the carriage and configured for rotating to carry the flowable resin to an application for application to produce the object, and an exposure device mounted on the carriage. The exposure device emits electromagnetic waves to an exposure site to solidify the applied flowable material to produce the object. The roller is permeable to the electromagnetic waves, such that the waves pass through the roller in traveling from the exposure device to the exposure site.

A method for the lithography-based additive manufacture of three-dimensional molded bodies, in which a build platform is positioned at a distance from a material support, which is permeable to the radiation of a radiation source at least in some areas, for a material solidifiable by exposure to said radiation, wherein the material support is translationally moved between a first position and a second position, characterized in that material is applied with a defined layer thickness during the movement of the material support from the first position to the second position, after this the applied material, between the build platform and the material support, is location- and/or time-selectively irradiated by the radiation source and solidified, and subsequently material is removed from the material support during the movement of the material support from the second position to the first position.

A method of and an apparatus (1,29) for forming an object by means of additive manufacturing, the method comprising consecutively providing a plurality of layers (9) of building material (5, 6), and selectively curing one or more pixels (47) of each of the layers (9) during printing thereof. The method comprises a step of providing a first layer (9) of a first building material (5) onto a support surface (4, 30) or a preceding layer (9), and selectively exposing, in accordance with layer data, one or more pixels (47) in the first layer (9) to a dose of radiation (45, 45′). It further comprises the identifying, based on the layer data, of one or more contour pixels (47) in the first layer (9) that coincide with a contour of a featured region of a subsequent second layer (9), wherein the featured region of the second layer (9) is to be provided using a second building material (6) different from the first building material (5). The method also comprises increasing, prior to said selectively exposing, a radiation dose (45′) for the identified contour pixels (47). The step of selectively exposing includes exposing the one or more contour pixels (47) using the increased radiation dose (45′).

3-D printers include an intermediate transfer surface that transfers a layer of material to a platen each time the platen contacts the intermediate transfer surface to successively form a freestanding stack of layers of the material on the platen. A sensor detects the thickness of the layer on the platen after a fusing station fuses the layer. A feedback loop is electrically connected to the sensor and a development station (that includes a photoreceptor, a charging station providing a static charge to the photoreceptor, a laser device exposing the photoreceptor, and a development device supplying the material to the photoreceptor). The exposure device adjusts the intensity of light exposed on the photoreceptor, based on a layer thickness measurement from the sensor through the feedback loop, to control the thickness of subsequent ones of the layers transferred from the intermediate transfer surface to the freestanding stack on the platen.

A manufacturing method of a structure includes, in this order: providing a layer constituted by a support member and a modeling layer by bringing a regulating surface of a regulating member into contact with the modeling layer provided on a surface of an intermediate transfer member, pouring a material for the support member which becomes the support member to fill the periphery of the modeling layer while the regulating surface abutting the modeling layer, and solidifying the material for the support member; removing the regulating member from the layer constituted by the support member and the modeling layer.

3-D printers include a transfuse station having at least one roller on one side of an ITB supporting the ITB, and a transmission device on the same side of the ITB. A charge neutralizer is included on a second side of the intermediate transfer surface. The charge neutralizer outputs an opposite charge to neutralize existing static charge on a layer of the build material and the support material on the ITB, before the layer reaches the transfer station. Additionally, the intermediate transfer surface transfers the layer to a platen each time the platen contacts the second side of the intermediate transfer surface, at the transfer station, to successively form layers of the build material and the support material on the platen. Also, the transmission device outputs acoustic waves to cause the layer to move from the intermediate transfer surface to the platen, or to the layers on the platen.

A selective deposition-based additive manufacturing system capable of building a three-dimensional (3D) part utilizing a semi-crystalline polymeric material includes at least one electrostatographic engine configured to develop one or more layers of particles of semi-crystalline polymeric material corresponding to one or more slices of a 3D model of a 3D part. The system includes a transfer medium configured to receive the one or more layers of particles of the semi-crystalline polymeric material on a front side from the at least one electrostatographic engine and to move the one or more layers away from the electrostatographic engine and a platen configured to carry the 3D part or support being printed. The system includes a gantry coupled to the platen and configured to move the platen into registration with the one or more layers, and a heater configured to heat a top surface of the 3D part being printed to a transfuse temperature. The system includes a layer transfer assembly having a roller contacting a back side of the transfer medium and a driver configured to cause the layer to transfer from the front side of the transfer medium to the heated top surface of the part. The system includes a cooler configured to cool the heated semi-crystalline polymeric material at a maximum rate of at least 20° C. per second such that the semi-crystalline material is in a super-cooled state wherein the semi-crystalline polymeric material does not completely initially crystallize.

Methods and apparatus for the fabrication of solid three-dimensional objects from liquid polymerizable materials at high resolution. A material is coated on a film non-digitally, excess material is removed digitally, by laser, leaving an image of a layer to be printed, and the image is then engaged with existing portions of an object being fabricated and exposed to a non-digital UV curing light source. Since the only part of the process that is digital is the material removal, and this part is done by laser, the speed of printing and the robustness of the manufacturing process is improved significantly over conventional additive or 3D fabrication techniques.