Abstract: A test cell useful for determining the photosensitivity of a photopolymerizable material, includes a support plate having a top surface portion, a bottom surface portion, and an opening extending therebetween, a light-transmissive base member removably or permanently connected to said bottom surface portion to form with said opening a well, into which well photopolymerizable material can be deposited, and a sensor comprising a thermal sensor, strain sensor, or combination thereof operatively associated with said light-transmissive base member.

Abstract: A method of reducing performance deviation in at least one additive manufacturing apparatus during production of parts is provided. Each apparatus has a light source configured for polymerizing a light polymerizable resin with sequential doses of patterned light to produce a 3D object. The light source has an assigned nominal emission data, such as an expected or preset standard emission data, and actual emission data. The method includes modifying at least some of said light doses in said at least one apparatus during production of parts therein to compensate for a deviation of said actual light source emission data from the assigned nominal emission data.

Abstract: A build plate for a three-dimensional printer includes: a rigid, optically transparent, gas-impermeable planar base having an upper surface and a lower surface; and a flexible, optically transparent, gas-permeable sheet having an upper and lower surface, the sheet upper surface comprising a build surface for forming a three-dimensional object, the sheet lower surface positioned on the base upper surface. The build plate includes a gas flow enhancing feature configured to increase gas flow to the build surface.

Abstract: An additive manufacturing apparatus (10) includes (a) a light polymerizable resin unit comprising a surface on which a light polymerizable resin can be supported; (b) a light engine (17) configured to illuminate a region of the light polymerizable resin unit; (c) a carrier platform on which an object can be produced; (d) a drive assembly operatively associated with the carrier platform for advancing said carrier platform (12) and said light polymerizable resin unit away from one another as said object is produced; (e) a purge chamber (300) surrounding at least a portion of said light engine (17); and (f) a purge gas in said purge chamber, or a purge gas supply operatively associated with said purge chamber (300).

Abstract: A build plate assembly for a three-dimensional printer includes: a lighting panel having individually addressable pixels configured to selectively emit light and/or transmit light from illumination below the pixels to a top surface top surface of the lighting panel; a rigid, optically transparent, gas-impermeable planar screen or base having an upper surface having an uneven surface topology and a lower surface that is affixed to the top surface of the lighting panel; and a flexible, optically transparent, gas-permeable sheet having upper and lower surfaces, the upper surface comprising a build surface for forming a three-dimensional object, the sheet lower surface positioned opposite the base, wherein the build plate is configured to permit gas flow to the build surface.

Abstract: A build plate for a three-dimensional printer includes a rigid, optically transparent, gas-permeable planar base having an upper surface and an opposing lower surface; a gas permeable adhesive layer on the base upper surface; and a flexible, optically transparent, gas-permeable sheet having upper and lower surfaces, the upper surface comprising a build surface for forming a three-dimensional object, the sheet lower surface positioned on the adhesive layer opposite the base.

Abstract: A build plate for a three-dimensional printer includes: a rigid, optically transparent, gas-impermeable planar base having an upper surface and a lower surface; and a flexible, optically transparent, gas-permeable sheet having an upper and lower surface, the sheet upper surface comprising a build surface for forming a three-dimensional object, the sheet lower surface positioned on the base upper surface. The build plate includes a gas flow enhancing feature configured to increase gas flow to the build surface.

Abstract: A build plate for a three-dimensional printer includes a rigid, optically transparent, gas-permeable planar base having an upper surface and an opposing lower surface; a gas permeable adhesive layer on the base upper surface; and a flexible, optically transparent, gas-permeable sheet having upper and lower surfaces, the upper surface comprising a build surface for forming a three-dimensional object, the sheet lower surface positioned on the adhesive layer opposite the base.

Abstract: Provided herein is a polymerizable liquid composition useful for additive manufacturing, which composition may include: (i) a free radical photoinitiator; (ii) monomers and/or prepolymers (e.g., reactive diluents) that are polymerizable by exposure to actinic radiation or light, optionally wherein some or all of said monomers and/or prepolymers comprise one or more acid-labile or base-labile groups; (iii) a crosslinker comprising one or more acid-labile or base-labile groups; and (iv) a photoacid generator or a photobase generator, wherein said free radical photoinitiator and said photoacid generator or photobase generator are, or are selected to be, activated by light at different ranges of wavelengths or intensities. Methods of forming a three-dimensional object with the composition, and articles so formed are also provided. Methods of removing a portion of the article by dissolving in a polar or non-polar solvent are further provided.

Abstract: Provided herein is a polymerizable liquid composition useful for additive manufacturing, which composition may include: (i) a free radical photoinitiator; (ii) monomers and/or prepolymers (e.g., reactive diluents) that are polymerizable by exposure to actinic radiation or light, optionally wherein some or all of said monomers and/or prepolymers comprise one or more acid-labile groups; (iii) a chain extender, optionally wherein said chain extender comprises one or more acid-labile groups; and (iv) a photoacid generator, wherein at least one of said monomers and/or prepolymers, or said chain extender, comprises one or more acid-labile groups, and wherein said free radical photoinitiator and said photoacid generator are, or are selected to be, activated by light at different ranges of wavelengths or intensities. Methods of forming a three-dimensional object with the composition, and articles so formed are also provided.

Abstract: A build plate assembly for a three-dimensional printer includes: a lighting panel having individually addressable pixels configured to selectively emit light and/or transmit light from illumination below the pixels to a top surface top surface of the lighting panel; a rigid, optically transparent, gas-impermeable planar screen or base having an upper surface having an uneven surface topology and a lower surface that is affixed to the top surface of the lighting panel; and a flexible, optically transparent, gas-permeable sheet having upper and lower surfaces, the upper surface comprising a build surface for forming a three-dimensional object, the sheet lower surface positioned opposite the base, wherein the build plate is configured to permit gas flow to the build surface.

Abstract: Provided herein is a polymerizable liquid composition useful for additive manufacturing, which composition may include: (i) a free radical photoinitiator; (ii) monomers and/or prepolymers (e.g., reactive diluents) that are polymerizable by exposure to actinic radiation or light, optionally wherein some or all of said monomers and/or prepolymers comprise one or more acid-labile or base-labile groups; (iii) a crosslinker comprising one or more acid-labile or base-labile groups; and (iv) a photoacid generator or a photobase generator, wherein said free radical photoinitiator and said photoacid generator or photobase generator are, or are selected to be, activated by light at different ranges of wavelengths or intensities. Methods of forming a three-dimensional object with the composition, and articles so formed are also provided. Methods of removing a portion of the article by dissolving in a polar or non-polar solvent are further provided.

Abstract: A build plate for a three-dimensional printer includes two or more flexible, optically transparent, gas-permeable sheets having upper and lower surfaces, the upper surface of a top one of the two or more gas-permeable sheets comprising a build surface for forming a three-dimensional object; and adhesive layers between each of the two or more sheets, wherein the two or more sheets and the adhesive layers together form a gas-permeable, rigid, optically transparent build plate that is configured to permit gas flow to the build surface.

Abstract: A build plate for a three-dimensional printer includes a rigid, optically transparent, gas-permeable planar base having an upper surface and an opposing lower surface; a gas permeable adhesive layer on the base upper surface; and a flexible, optically transparent, gas-permeable sheet having upper and lower surfaces, the upper surface comprising a build surface for forming a three-dimensional object, the sheet lower surface positioned on the adhesive layer opposite the base.

Abstract: Provided herein is a polymerizable liquid composition useful for additive manufacturing, which composition may include: (i) a free radical photoinitiator; (ii) monomers and/or prepolymers (e.g., reactive diluents) that are polymerizable by exposure to actinic radiation or light, optionally wherein some or all of said monomers and/or prepolymers comprise one or more acid-labile groups; (iii) a chain extender, optionally wherein said chain extender comprises one or more acid-labile groups; and (iv) a photoacid generator, wherein at least one of said monomers and/or prepolymers, or said chain extender, comprises one or more acid-labile groups, and wherein said free radical photoinitiator and said photoacid generator are, or are selected to be, activated by light at different ranges of wavelengths or intensities. Methods of forming a three-dimensional object with the composition, and articles so formed are also provided.

Abstract: A build plate for a three-dimensional printer includes: a rigid, optically transparent, gas-impermeable planar base having an upper surface and a lower surface; and a flexible, optically transparent, gas-permeable sheet having an upper and lower surface, the sheet upper surface comprising a build surface for forming a three-dimensional object, the sheet lower surface positioned on the base upper surface. The build plate includes a gas flow enhancing feature configured to increase gas flow to the build surface.