Abstract: In one aspect, support materials operable for use in 3D printing systems are described herein. In some embodiments, a support material comprises a wax component comprising at least one ethoxylated fatty alcohol and a viscosity modifying agent, wherein the support material is water dispersible. In some embodiments, the wax component comprises a mixture of at least one fatty alcohol and at least one ethoxylated fatty alcohol.

Abstract: In one aspect, support materials operable for use in 3D printing systems are described herein. In some embodiments, a support material comprises a wax component comprising at least one ethoxylated fatty alcohol and a viscosity modifying agent, wherein the support material is water dispersible. In some embodiments, the wax component comprises a mixture of at least one fatty alcohol and at least one ethoxylated fatty alcohol.

Abstract: There are provided method and apparatus for the forming of three-dimensional objects in a layered fashion, wherein improvements are made to the support structure to improve the quality of the resulting three-dimensional objects. The support structure may include encapsulation along the interface boundary of the support-object interface to prevent or reduce the likelihood of separation of the build material, that forms the three-dimensional object, from the support material, that forms the support structure, or vice versa. The support structure may also or alternatively include both a porous support structure and a solid support structure to prevent or reduce the likelihood of separation of the support structure from the build platform and to improve the quality of the down-facing surfaces of the three-dimensional object. Methods are also provided for selectively depositing the support material and build material and for encapsulating the interface boundary with support material.

Abstract: In one aspect, support materials operable for use in 3D printing systems are described herein. In some embodiments, a support material comprises a wax component comprising at least one ethoxylated fatty alcohol and a viscosity modifying agent, wherein the support material is water dispersible. In some embodiments, the wax component comprises a mixture of at least one fatty alcohol and at least one ethoxylated fatty alcohol.

Abstract: There is provided methods and apparatus for improving the accuracy of three-dimensional objects formed by additive manufacturing. By depositing or hardening build material within the interior of the layers in certain patterns, the stresses that lead to curl in the object can be isolated and controlled. Similarly, certain patterns for depositing or hardening the build material provide for reduced layer thicknesses to improve the sidewall quality of the object being formed. The patterns within the interior of the layers can include gaps or voids for particular layers being deposited or hardened, and the gaps or voids can be partially filled, fully filled, or not filled at all when subsequent layers are deposited or hardened. Accordingly, the accuracy of three-dimensional objects formed by additive manufacturing is improved.

Abstract: There are provided method and apparatus for the forming of three-dimensional objects in a layered fashion, wherein improvements are made to the support structure to improve the quality of the resulting three-dimensional objects. The support structure may include encapsulation along the interface boundary of the support-object interface to prevent or reduce the likelihood of separation of the build material, that forms the three-dimensional object, from the support material, that forms the support structure, or vice versa. The support structure may also or alternatively include both a porous support structure and a solid support structure to prevent or reduce the likelihood of, separation of the support structure from the build platform and to improve the quality of the down-facing surfaces of the three-dimensional object. Methods are also provided for selectively depositing the support material and build material and for encapsulating the interface boundary with support material.

Abstract: A post-processing system is provided for cleaning and/or curing a part produced by solid freeform fabrication (SFF). The post-processing systems include a housing, a part retaining device to retain the part within the housing, and an actinic radiation source to cure the part with actinic radiation. The systems also include a fluid circulation device adapted to expose the part to cleaning fluid and/or to allow the cleaning fluid to absorb actinic radiation to permit filtration of removed build material to allow extended use of the cleaning fluid. Certain systems include a first rotating portion that can rotate the retained part about a first axis, and further systems include a second rotating portion that can rotate the retained part about a second axis. The systems also include additional features to provide safe and efficient cleaning and/or curing of parts produced by SFF.

Abstract: A post-processing system is provided for cleaning and/or curing a part produced by solid freeform fabrication (SFF). The post-processing systems include a housing, a part retaining device to retain the part within the housing, and an actinic radiation source to cure the part with actinic radiation. The systems also include a fluid circulation device adapted to expose the part to cleaning fluid and/or to allow the cleaning fluid to absorb actinic radiation to permit filtration of removed build material to allow extended use of the cleaning fluid. Certain systems include a first rotating portion that can rotate the retained part about a first axis, and further systems include a second rotating portion that can rotate the retained part about a second axis. The systems also include additional features to provide safe and efficient cleaning and/or curing of parts produced by SFF.

Abstract: A continuous-wave (CW) ultraviolet (UV) curing system for solid freeform fabrication (SFF) is provided, wherein the curing system is configured to provide an exposure of UV radiation for one or more layers of UV-curable material. One or more UV exposures may initiate curing of a curable material in the layer dispensed by a solid freeform fabrication apparatus. One approach to provide the single or multiple UV exposures is the use of one or more UV LEDs, which generate UV radiation without generating any substantial amounts of infrared (IR) radiation at the same time. This allows for the curing process to be energy efficient and also allows for the SFF system to be far less complex.

Abstract: The invention relates to a method producing parts using laser sintering wherein a fusible powder is exposed to a plurality of laser scans at controlled energy levels and for time periods to melt and densify the powder and in the substantial absence of particle bonding outside the fusion boundary. Strength is improved up to 100% compared to previous methods. An example includes a relatively high energy initial scan to melt the powder followed by lower energy scans controlled to densify the melt and separated in time to dissipate heat to the surrounding part cake. The rate and extent to which the powder particles are fused together can be controlled so that each successive scan can be used to fuse the particles together in discreet incremental steps. As a result, the final dimensions of the part and its density and mechanical properties can be improved compared to conventional methods and part growth avoided.

Abstract: The invention relates to a process for the manufacture of coatings by radiocrosslinking. A radio-crosslinkable composition (C) is produced first of all by mixing at least one (meth)acrylic compound (A) with a reactive diluent system comprising at least one mono(meth)acrylic carbonate (B) corresponding to the general formula (I): ##STR1## in which: R.sub.1 denotes H or CH.sub.3R.sub.2 denotes an alkylene ether or alkylene chain which has a total number of carbon atoms of between 2 and 6,n denotes an integer between 1 and 6.The composition (C) is next applied onto a substrate and is then radiocrosslinked, preferably using UV radiation.Another subject of the invention is the crosslinkable compositions (C) in which the compound (A) and the carbonate (B) are not simultaneously 2,3-carbonyldioxypropyl 2-methacryloyloxyethyl carbonate, and carbonates of general formula (I) in which R.sub.2 denotes (CH.sub.2).sub.m and in which m and n are integers such that 2.ltoreq.m.ltoreq.6, 1.ltoreq.n.ltoreq.6 and n.noteq.