Described are methods and apparatus for the inspection of cured layers of an object during the fabrication of the object using a 3D printing system. A just-printed layer may be inspected by pressing the layer against a pressure-sensitive surface in order to collect information about the layer. For example, a tank may contain a photo-curing liquid polymer, and at its bottom are pressure sensitive elements (e.g., in a backing member or mask). An extraction plate to which the object is affixed may be adjusted so as to position a surface of the object adjacent to the pressure sensitive elements, which report a pressure distribution (e.g., by virtue of a force exerted by a localized region of the object on a localized region of the pressure sensitive elements).

The present invention relates to polyetherimide polymers which can for example be used in lithographic processes for the photofabrication of three-dimensional (3D) articles. The invention further relates to compositions including these polyetherimide polymers. Still further, the invention relates to lithographic methods to form 3D articles or objects that incorporate the aforementioned polymer compositions.

The present invention relates to polyetherimide polymers which can for example be used in lithographic processes for the photofabrication of three-dimensional (3D) articles. The invention further relates to compositions including these polyetherimide polymers. Still further, the invention relates to lithographic methods to form 3D articles or objects that incorporate the aforementioned polymer compositions.

Provided is a method of recycling an additively manufactured object into a reusable thermoplastic polymer, which method in some embodiments may include: (a) providing at least one additively manufactured object produced by stereolithography from a dual cure resin, the object comprising (i) a light polymerized polymer, and (ii) a heat polymerized polymer intermixed with said light polymerized polymer; (b) comminuting the object to produce a particulate material therefrom; (c) contacting the particulate material to a polar, aprotic solvent for a time and at a temperature sufficient to extract the heat polymerized polymer from the particulate material into said solvent, leaving residual particulate material comprising said light polymerized polymer in solid form; (d) separating the residual particulate material from said solvent; and then (e) separating the heat polymerized polymer from said solvent to provide a reusable thermoplastic polymer material in solid form.

An additive manufacturing apparatus includes a support plate and a foil supporting an uncured layer of a resin. A stage is configured to hold a component of one or more cured layers of the resin. One or more actuators is operable to move the stage away from the support plate in a Z-axis direction. A radiant energy device is positioned opposite the stage such that the support plate is positioned between the radiant energy device and the stage. A foil interaction device includes a first pneumatic actuation zone and a second pneumatic actuation zone. Each of the first and second pneumatic actuation zones is configured to apply a force on a surface of the foil. The first and second pneumatic actuation zones are fluidly separable and configured to apply varied pressures relative to one another to the surface of the foil.

An additive manufacturing apparatus includes a support plate and a foil supporting an uncured layer of a resin. A stage is configured to hold a component of one or more cured layers of the resin. One or more actuators is operable to move the stage away from the support plate in a Z-axis direction. A radiant energy device is positioned opposite the stage such that the support plate is positioned between the radiant energy device and the stage. A foil interaction device includes a first pneumatic actuation zone and a second pneumatic actuation zone. Each of the first and second pneumatic actuation zones is configured to apply a force on a surface of the foil. The first and second pneumatic actuation zones are fluidly separable and configured to apply varied pressures relative to one another to the surface of the foil.

A stereolithography method of manufacture of a polymer structure having a spatially gradient dielectric constant, including: providing a volume of a liquid, radiation-curable composition; irradiating a portion of the liquid, radiation-curable composition with activating radiation in a pattern to form a layer of the polymer structure; contacting the layer with the liquid, radiation-curable composition; irradiating the liquid, radiation-curable composition with activating radiation in a pattern to form a second layer on the first layer; and repeating the contacting and irradiating to form the polymer structure, wherein the polymer structure comprises a plurality of unit cells wherein each unit cell is integrally connected with an adjacent unit cell, each unit cell is defined by a plurality of trusses formed by the irradiation, wherein the trusses are integrally connected with each other at their respective ends, and the trusses of each unit cell are dimensioned to provide the spatially gradient dielectric constant.

A stereolithography method of manufacture of a polymer structure having a spatially gradient dielectric constant, including: providing a volume of a liquid, radiation-curable composition; irradiating a portion of the liquid, radiation-curable composition with activating radiation in a pattern to form a layer of the polymer structure; contacting the layer with the liquid, radiation-curable composition; irradiating the liquid, radiation-curable composition with activating radiation in a pattern to form a second layer on the first layer; and repeating the contacting and irradiating to form the polymer structure, wherein the polymer structure comprises a plurality of unit cells wherein each unit cell is integrally connected with an adjacent unit cell, each unit cell is defined by a plurality of trusses formed by the irradiation, wherein the trusses are integrally connected with each other at their respective ends, and the trusses of each unit cell are dimensioned to provide the spatially gradient dielectric constant.

A method for producing a three-dimensional object by an additive manufacturing process includes introducing at least one manufacturing material fed in a flowable state from at least one feed-in opening of at least one feed-in needle into a supporting material. After being fed in, the at least one manufacturing material is cured, but it remains flexible or elastic after curing. The contour and/or position of at least one part of the three-dimensional object within the support material is detected by at least one sensor.

A method for producing a three-dimensional object by an additive manufacturing process includes introducing at least one manufacturing material fed in a flowable state from at least one feed-in opening of at least one feed-in needle into a supporting material. After being fed in, the at least one manufacturing material is cured, but it remains flexible or elastic after curing. The contour and/or position of at least one part of the three-dimensional object within the support material is detected by at least one sensor.