Abstract: An additive manufacturing (AM) system includes a carriage that deposits material in a defined pattern and a building platform that receives material deposited from the carriage. The carriage includes a pre-heating assembly with a plurality of pre-heating chambers and a printing block with a plurality of slots for receiving a plurality of printing heads. The carriage is equipped with more pre-heating chambers than head slots.

Abstract: Formulations usable in additive manufacturing, 3D inkjet printing in particular, of a three-dimensional object that contains a polyimide material, and additive manufacturing utilizing same are provided. The formulations contain a polyimide precursor (e.g., a bismaleimide) and an additional curable material, which is a multifunctional curable material, and are devoid of an organic solvent.

Abstract: Formulations usable in additive manufacturing such as 3D inkjet printing which provide a transparent material when hardened, are provided. The formulation are designed so as to provide transparent objects or parts thereof with improved transmittance and color properties such as yellowness index, compared to commercially available formulations. The formulations comprise a photoinitiator at a relatively low amount and designed mixture of curable materials.

Abstract: A method of additive manufacturing, comprises: dispensing from an array of nozzles an amount of building material formulation to form a layer in a configured pattern corresponding to a shape of a slice of an object, and hardening the layer. Based on the amount and a geometrical characteristic of the slice, a thermal mass of the layer is calculated. A cooling system is controlled in a closed loop control responsively to the calculated thermal mass.

Abstract: A method of three-dimensional printing, comprises: operating a printing head having a nozzle array to dispense a building material formulation, wherein the printing head is directly connected to a cartridge containing the building material formulation, and wherein the printing head comprises a channel conveying a building material formulation received from the cartridge to the nozzle array; discarding the building material formulation from the channel; and connecting a cartridge containing a building material formulation that is different from the discarded building material formulation to the channel.

Abstract: A method of three-dimensional fabrication of an object is disclosed. The method comprises: forming a plurality of layers in a configured pattern corresponding to the shape of the three-dimensional object, at least one layer of the plurality of layers being formed at a predetermined and different thickness selected so as to compensate for post-formation shrinkage of the layer along a vertical direction. In various exemplary embodiments of the invention spread of building material of one or more layers is diluted at least locally such as to maintain a predetermined thickness and a predetermined planar resolution for the layer.

Abstract: A method of additive manufacturing a three-dimensional object by layerwise deposition of a building material with an inkjet printing system comprising a print head and a building tray, comprises calculating a weighting value for each nozzle, then for each layer obtaining a 2-D map of the layer, comprising active pixels at building material dispensing positions; obtaining a Data Correction Filter (DCF) including a height map of the previous layer, comparing the data of the 2D map to the data of the DCF at each position and determining if the nozzle at that position should dispense, then printing the layer, updating the weighting values and adjusting the position of the print head vis a vis the printing tray. The above is repeated until the three-dimensional object is printed.

Abstract: A system for additive manufacturing comprises a dispensing head for dispensing building materials on a working surface, a hardening system for hardening the building materials, a cooling system for evacuating heat away from the building materials, and a computerized controller. A thermal sensing system is mounted above the working surface in a manner that allows relative motion between the sensing system and the working surface, and is configured to generate sensing signals responsively to thermal energy sensed thereby. The controller controls the dispensing head to dispense the building materials in layers, the sensing system to generate the sensing signals only when the sensing system is above the building materials once hardened, and the heat evacuation rate of the cooling system responsively to the sensing signals.

Abstract: A method of additive manufacturing comprises receiving digital data defining a shape of a three-dimensional object and based on the digital data, sequentially dispensing and solidifying a plurality of layers made of a modeling material and arranged in a configured pattern corresponding to the shape of the object. A portion of the layers forms one or more stacks, each encompassing a non-solid substance trapped between a plurality of building material pillars oriented perpendicularly to the layers.

Abstract: Formulations and methods employing these formulation for fabricating an object by additive manufacturing, such as three-dimensional inkjet printing are provided. The formulations comprise at least 50 weight percents of hydrophilic curable materials, and upon curing, provide a material that is characterized by water absorbance of at least 5%, and by high HDT and impact resistance values. Objects containing cured material made of these formulations are also provided.

Abstract: Novel support material formulations, characterized as providing a cured support material with improved dissolution rate, while maintaining sufficient mechanical strength, are disclosed. The formulations comprise a water-miscible non-curable polymer, a first water-miscible, curable material and a second, water-miscible material that is selected capable of interfering with intermolecular interactions between polymeric chains formed upon exposing the first water-miscible material to curing energy. Methods of fabricating a three-dimensional object, and a three-dimensional object fabricated thereby are also disclosed.

Abstract: A support material formulation for use in additive manufacturing of a three-dimensional object, which, when hardened, is soluble upon immersion in water, is provided. The formulation includes a hydrophilic curable mono-functional material; a polyol (e.g., a branched polyol) having a molecular weight lower than 1,000, or lower than 800 grams/mol; and a polyester material having a molecular weight higher than 400, or higher than 500, grams/mol. Additive manufacturing using the disclosed formulation and objects made thereby are also provided.

Abstract: A formulation system usable in additive manufacturing of a three-dimensional object that comprises, in at least a portion thereof, a cyanate ester-containing polymeric network, and additive manufacturing processes employing the formulation system are provided. Also provided are objects obtainable by the additive manufacturing and kits containing the formulation system. The formulation system includes a first modeling material formulation which includes a first curable material which is a thermally-curable cyanate ester and a second modeling material formulation which comprises an activating agent for promoting polymerization of the cyanate ester and is devoid of the first curable material, and further includes a second curable material which is different from the first curable material, and optionally an agent for promoting hardening of the second curable material.

Abstract: A method of fabricating an object in layers, comprises, for at least one layer: dispensing a building material formulation to form a first portion of the layer, and leveling the first portion by a leveling device; increasing a vertical distance between the first portion and the leveling device; and while a topmost surface of the first portion is exposed and beneath a segment of the leveling device: dispensing a building material formulation to form a second portion of the layer, laterally displaced from the first portion along an indexing direction, and leveling the second portion by the leveling device.

Abstract: Modeling material formulation systems usable in additive manufacturing, 3D inkjet printing in particular, of three-dimensional objects, are provided. The formulations comprise two or more curable materials, such that an average molecular weight of the curable materials in each formulation is no more than 500 grams/mol, such that each formulation features a viscosity of no more than 50 centipoises at a temperature of 35° C. Kits comprising the formulations or formulation systems and additive manufacturing processes utilizing same are also provided.

Abstract: Modeling material formulations and formulation systems usable in additive manufacturing of a three-dimensional object, featuring, when hardened, a Shore A hardness lower than 10 and/or a Shore 00 hardness lower than 40, are provided. Additive manufacturing processes utilizing these formulations and formulation systems, and three-dimensional objects obtainable thereby, are also provided.

Abstract: A method of encoding data for additive manufacturing comprises: displaying a graphical user interface (GUI) having at least a planar segment selector control, a pattern shaping control, and a material selection control. The method also comprises displaying on the GUI a cross-section of a three-dimensional object at a position corresponding to a specific planar segment selected by the planar segment selector control. A planar pattern having nested contours is displayed over the cross-section, wherein each contour is shaped according to an input received by the pattern shaping control and is associated with at least one building material according to an input received by the material selection control. A data structure describing the planar pattern is stored in a computer storage.

Abstract: Formulation systems usable for fabricating a three-dimensional object made of a polyamide-containing material, by three-dimensional 3D inkjet printing, and methods and systems utilizing same, are provided. The formulation systems are formed of at least a first and second model formulations containing a lactam and a catalyst for inducing anionic ring opening polymerization of the lactam in the first formulation, and an activator for promoting anionic ring opening polymerization of the lactam in the second formulation, and are further characterized as: including in the first and/or second formulation a compound capable of increasing a rate of said polymerization upon exposure to said curing energy; including as an activator a lactam-blocked polyisocyanate; and/or as including in the first model formulation at least one material capable of reducing a melting point of said first model formulation. Formulation systems usable at a selected ratio are also provided.

Abstract: A waste curing device to cure waste generated by an additive manufacturing system, the waste curing device comprising: a container for receiving the waste; a movable cover positioned above the container; one or more waste nozzles mounted on the moveable cover and configured to deliver waste into the container; a static cover positioned above the container and below the movable cover; one or more curing sources mounted on the static cover and configured to provide curing radiation to cure the waste in the container; wherein the movable cover is configured to move relative to the static cover to provide an open position for the waste nozzles to deliver waste into the container, and subsequently to a closed position, to shield the waste nozzles from curing radiation.

Abstract: A system and methods for solid freeform fabrication of an object is disclosed. The system comprises a solid freeform fabrication apparatus having a plurality of dispensing heads, a building material supply apparatus configured to supply a plurality of building materials to the fabrication apparatus, and a control unit configured for controlling the fabrication apparatus and the supply apparatus based on an operation mode selected from a plurality of predetermined operation modes.