Systems and methods for making it easier to remove support structures printed in conjunction with printing an object using stereolithographic additive manufacturing are disclosed. In some exemplary embodiments, one or more interfaces between the printed object and the support structures are modulated to allow for easy separation between them, in some instances even when the object and support structures are made from the same material. Various modulation techniques are disclosed, including adjusting an intensity of exposure to light at interfaces between the object and support structures, and using two materials where one material cures at two wavelength ranges and the other material only cures at one of the two wavelength ranges. Other systems and methods that allow for easy separation of part and support structure are also described.

A method of forming a three-dimensional object is carried out by: (a) providing a carrier and an optically transparent member having a build surface, the carrier and the build surface defining a build region therebetween; (b) filling the build region with a polymerizable liquid, the polymerizable liquid including a mixture of (i) a light polymerizable liquid first component, and (ii) a second solidifiable component that is different from the first component; (c) irradiating the build region with light through the optically transparent member to form a solid polymer scaffold from the first component and also advancing the carrier away from the build surface to form a three-dimensional intermediate having the same shape as, or a shape to be imparted to, the three-dimensional object, and containing the second solidifiable component carried in the scaffold in unsolidified and/or uncured form; and (d) concurrently with or subsequent to the irradiating step, solidifying and/or curing the second solidifiable component in the three-dimensional intermediate to form the three-dimensional object.

Anti-fog compositions comprising a primary film having opposing major planar surfaces and a central coplanar region disposed between the opposing major planar surfaces and comprising cellulose acetate and a plasticizer. The cellulose acetate may have a degree of substitution less than 2.6. The plasticizer may be selected from the group consisting of 1,2,3-triacetoxypropane (triacetin), tributyl citrate, triethyl citrate, triphenyl phosphate, tris(clorisopropyl)phosphate, dimethyl phthalate, diethyl phthalate, bornan-2-one, PEG-DGE, PPG-DGE, tributyl phosphate, and combinations thereof. The primary film has a thickness greater than 90 microns.

Systems, methods, and devices for additive manufacturing are provided. In some embodiments, a method includes: coupling a plurality of build platforms to a carrier; forming a plurality of 3D objects on the plurality of build platforms using an additive manufacturing process, where each build platform receives at least one 3D object thereon; removing the plurality of build platforms from the carrier; performing post-processing of the plurality of 3D objects while the 3D objects remain on the respective build platforms; and separating the plurality of 3D objects from the respective build platforms.

A method for producing a resin sintered body 1 by applying an ink 3 to thermoplastic resin powder 2 and sintering the powder, the method including the step of immersing an intermediate resin sintered body 1m, which has an unevenly colored region on the surface thereof and the whole of which has been already sintered, in a surface treatment liquid containing sulfuric acid and chromic anhydride, in which the concentration of chromic anhydride is 300 g/L or more, for 5 minutes or longer. When producing a resin sintered body by sintering thermoplastic resin powder, the surface of the resin sintered body can be evenly and sufficiently colored to an extent required without an unevenly colored region on the surface thereof, and also the surface of the resin sintered body can have a good appearance and smoothness.

Porous and microporous parts prepared by additive manufacturing as disclosed herein are useful in medical and non-medical applications. The parts are prepared from a composition containing both a solvent soluble component and a solvent insoluble component. After a part is printed by an additive manufacturing process it is exposed to solvent to extract solvent soluble component away front the printed part, resulting in a part having surface cavities.

The present application relates to a method for post-processing a powder-based additively manufactured part. The method comprising the steps of providing a powder-based additively manufactured part, the additively manufactured part comprising a material having a melting point, providing a fluid for processing the additively manufactured part in order to improve the surface finish of the additively manufactured part, wherein the fluid comprises at least one solvent selected from an organic ester, an aromatic organic compound or an acetal, a heating step, wherein the fluid is heated; and an application step, wherein the heated fluid is applied to a surface of the additively manufactured part. It has been found this process can help to improve the surface finish of the additively manufactured part, e.g. resulting in a less rough (i.e. smoother) surface finish.

Methods for manufacturing objects are provided herein. In some embodiments, a method includes receiving a digital data set representing an object, and applying energy to a curable material based on the digital data set to form the object. The object can include at least two object portions formed from the curable material using different energy application parameters. The method can further include removing residual curable material from the object. A different amount of the residual curable material can be removed from each of the at least two object portions. After the residual curable material is removed, the at least two object portions can each have different material properties.

Methods for manufacturing objects are provided herein. In some embodiments, a method includes receiving a dental appliance formed using an additive manufacturing process, the dental appliance including a plurality of appliance portions. The method can include identifying, based on sensor data, a location of a subset of the appliance portions on the dental appliance. The method can further include applying energy to a subset of the appliance portions to selectively modify one or more material properties of the subset of the appliance portions.

The present disclosure provides an orthodontic article including the reaction product of the polymerizable composition. Further, the present disclosure provides polymerizable compositions and methods of making an orthodontic article. The method includes obtaining a polymerizable composition and selectively curing the polymerizable composition to form an orthodontic article. Further, methods are provided, including receiving, by a manufacturing device having one or more processors, a digital object comprising data specifying an orthodontic article; and generating, with the manufacturing device by an additive manufacturing process, the orthodontic article based on the digital object. A system is also provided, including a display that displays a 3D model of an orthodontic article; and one or more processors that, in response to the 3D model selected by a user, cause a 3D printer to create a physical object of an orthodontic article.