Sacrificial additively manufactured molds having a dissolvable material for use in thermoplastic injection molding processes at plastic melt temperatures in the range of 70-450 degrees C. and injection pressure in the range of 0.2-400 MPa. A method of producing a molded article using said sacrificial additively manufactured molds is also disclosed.

The method of manufacturing a transparent whitening tray according to the present invention includes 3D printing of the whitening tray using the composition for forming a transparent whitening tray as a raw material (S10), removing uncured resin and liquid from the whitening tray obtained in the above step (S20), post-curing the whitening tray obtained in the above step (S30), post-heat treating the whitening tray obtained in the above step (S40), and washing the whitening tray obtained in the above step (S40).

It is provided an extrusion device for a plastic profile, in particular a hollow chamber profile, with an extruder, an extrusion nozzle arranged at the exit of the extruder for forming the plastic profile the plastic profile subsequently being guided through a calibration device, a downstream removal device for the plastic profile, a cutting device for cutting off parts of the extruded plastic profile and a weighing device for measuring the profile weight. A profile monitoring device is provided for detecting at least one profile parameter of the plastic profile in the extrusion direction after it has emerged from the extrusion nozzle and/or a process monitoring device is provided for detecting at least one process parameter in and/or before of the extruder, the extrusion nozzle, the calibration device, the removal device and/or the cutting device.

A powder removal apparatus includes an extraction housing comprising a sidewall that is sized and configured to extend around a powder bed of a build module and a top wall that is sized and configured to extend between opposite sides of the sidewall and over the powder bed. The sidewall and top wall are configured to form a chamber portion of a turbulence chamber. The top wall has a vacuum exit opening that is configured to fluidly connect to a vacuum source. The sidewall has a plurality of sidewall inlet flow channels that extend from an inlet opening at an exterior side of the sidewall to an outlet opening at an interior side of the sidewall. A side exit channel is configured to extend along the top wall from a collector opening in communication with the chamber portion toward the vacuum exit opening.

The present invention relates to photohardenable compositions and methods of forming an object, the method preferably including a photohardenable composition described herein. Preferred photohardenable compositions and methods include a photohardenable resin component, a first photoinitiator that is activatable by exposure to light at a first wavelength and light at a second wavelength, and a second photoinitiator that is activatable by exposure to light at a third wavelength, wherein the first, second, and third wavelengths are not the same, and the third wavelength is shorter than the first wavelength and the second wavelength. Preferred first photoinitators include photoswitchable photoinitiators. Preferably the second light-activated photoinitiator comprises a free-radical photoinitiator. Hardenable resin compositions and methods of forming an object including the hardenable resin composition are also disclosed.

A powder removal apparatus includes an extraction housing comprising a sidewall that is sized and configured to extend around a powder bed of a build module and a top wall that is sized and configured to extend between opposite sides of the sidewall and over the powder bed. The sidewall and top wall are configured to form a chamber portion of a turbulence chamber. The top wall has a vacuum exit opening that is configured to fluidly connect to a vacuum source. The sidewall has a plurality of sidewall inlet flow channels that extend from an inlet opening at an exterior side of the sidewall to an outlet opening at an interior side of the sidewall. A side exit channel is configured to extend along the top wall from a collector opening in communication with the chamber portion toward the vacuum exit opening.

A method for post-curing a 3D printing output and a transparent orthodontic device manufactured by the method are described. The method for post-curing a 3D printing output removes residual resin from printouts manufactured through a 3D printer, shortens the curing time by improving the curing speed through a post-curing process, and can manufacture printouts with improved strength and increased transparency. The transparent orthodontic device removes resin of the surface through the post-curing process when manufacturing a transparent orthodontic device, improves strength, not only has excellent transparency, but also enables unreacted monomers to be removed, and can exhibit shape memory characteristics that restore its shape to the initially printed-out shape of the transparent orthodontic device by the provision of heat.

A method and apparatus are set forth for volumetric additive manufacturing (VAM) wherein light rays that are used to determine tomographic projections are modelled using ray tracing, in order to account for projector non-telecentricity and etendue in all three dimensions. The path of rays from each light source (e.g. pixel) are computed as they propagate through the VAM system. Optical effects such as refraction, transmission loss, absorption, etendue, and non-telecentricity are intrinsically accounted for via ray tracing. Using these rays, the required dose to solidify the photosensitive resin is computed.