Abstract: A method suitable for solid freeform fabrication is disclosed. The method comprises mixing respective amounts of a plurality of materials such as to provide a building material characterized by at least one attribute, and using the building material for fabricating a three-dimensional object.

Abstract: A method for forming three-dimensional objects is disclosed. The method includes printing building material, layer by layer, to form a three dimensional object by depositing building material in layers onto a printing tray to form a three dimensional object and maintaining the uppermost layers being deposited in a flowable state by a temperature control after layers below the uppermost layers are solidified.

Abstract: A method of additive manufacturing of a three-dimensional object is disclosed. The method comprises sequentially forming a plurality of layers each patterned according to the shape of a cross section of the object. In some embodiments, the formation of at least one of the layers comprises performing a raster scan to dispense at least a first building material composition, and a vector scan to dispense at least a second building material composition. The vector scan is optionally along a path selected to form at least one structure selected from the group consisting of (i) an elongated structure, (ii) a boundary structure at least partially surrounding an area filled with the first building material, and (iii) an inter-layer connecting structure.

Abstract: A material composition, which may be a support material, for three-dimensional (3D) inkjet printing is disclosed. The material composition may comprise a glycol polymer, a low molecular weight polar substance and a surface-active agent. The glycol polymer may be polyethylene glycol (PEG) having a molecular weight between about 1000 and about 6000 and the low molecular weight polar substance may be dimethyl hexanediol.

Abstract: Apparatus for producing an object by sequentially forming thin layers of a construction material one on top of the other responsive to data defining the object, the apparatus comprising: a plurality of printing heads each having a surface formed with a plurality of output orifices and controllable to dispense the construction material through each orifice independently of the other orifices; a shuttle to which the printing heads are mounted; a support surface; and a controller adapted to control the shuttle to move back and forth over the support surface and as the shuttle moves to control the printing heads to dispense the construction material through each of their respective orifices responsive to the data to form a first layer on the support surface and thereafter, sequentially the other layers; wherein each printing head is dismountable from the shuttle and replaceable independently of the other printing heads.

Abstract: A three dimensional printing method for producing a self-destructible temporary structure, comprising: depositing, layer by layer, a degradable material solution having a biosynthetic copolymer as a degradable component and a disintegrating agent solution comprising enzyme as the disintegrating agent, wherein the disintegrating agent is capable of disintegrating the degradable component. The steps include curing deposited layers to form gel layers and activating the disintegrating agent by an external trigger during or after depositing the disintegrating agent to gradually degrade the degradable component.

Abstract: Apparatus for producing an object by sequentially forming thin layers of a construction material one on top of the other responsive to data defining the object, the apparatus comprising: a plurality of printing heads each having a surface formed with a plurality of output orifices and controllable to dispense the construction material through each orifice independently of the other orifices; a shuttle to which the printing heads are mounted; a support surface; and a controller adapted to control the shuttle to move back and forth over the support surface and as the shuttle moves to control the printing heads to dispense the construction material through each of their respective orifices responsive to the data to form a first layer on the support surface and thereafter, sequentially the other layers; wherein each printing head is dismountable from the shuttle and replaceable independently of the other printing heads.

Abstract: A material composition, which may be a support material, for three-dimensional (3D) inkjet printing is disclosed. The material composition may comprise a glycol polymer, a low molecular weight polar substance and a surface-active agent. The glycol polymer may be polyethylene glycol (PEG) having a molecular weight between about 1000 and about 6000 and the low molecular weight polar substance may be 1,8-octanediol.

Abstract: A liquid composition for producing a self-destructible temporary structure by additive manufacturing is provided. The liquid composition includes a biosynthetic copolymer as a degradable component and an enzyme as a disintegrating agent, the disintegrating agent is capable of disintegrating the degradable component, wherein after exposure to an external trigger, the disintegrating agent gradually degrades the degradable component.

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 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 for printing three dimensional objects and support compositions are disclosed. The composition includes at least one curable component and at least one non-curable component, the non-curable component being a polyol, a glycol or water, wherein none of said non-curable components is reactive with any of said curable components. The composition has a first viscosity of 20-500 cps at ambient temperature and a second viscosity of less than 20 cps at temperature higher than the ambient temperature. The composition results in a solid, a semi solid or a gel type material after radiation.

Abstract: A method of layerwise solid freeform fabrication is disclosed. The method comprises, for each of at least a few of the layers, dispensing and hardening at least a first modeling material and a second modeling material to form a core region and one or more envelope regions at least partially surrounding the core region. In some embodiments, the ratio between the elastic moduli of adjacent regions, when hardened, is from about 1 to about 20.

Abstract: A material composition, which may be a support material, for three-dimensional (3D) inkjet printing is disclosed. The material composition may comprise a glycol polymer, a low molecular weight polar substance and a surface-active agent. The glycol polymer may be polyethylene glycol (PEG) having a molecular weight between about 1000 and about 6000 and the low molecular weight polar substance may be 1,8-octanediol.

Abstract: A method of layerwise solid freeform fabrication is disclosed. The method comprises, for each of at least a few of the layers, dispensing and hardening at least a first modeling material and a second modeling material to form a core region and one or more envelope regions at least partially surrounding the core region. In some embodiments, the ratio between the elastic moduli of adjacent regions, when hardened, is from about 1 to about 20.

Abstract: The invention relates to a material composition, which may be a support material, for three-dimensional (3D) inkjet printing, comprising a glycol polymer, a low molecular weight polar substance and a surface active agent. The invention further provides a method for 3D inkjet printing comprising building a 3D object in layers, wherein at least one layer comprises a model material composition and a support material composition comprising PEG and a low molecular weight polar substance, wherein the layers are solidified before deposition of subsequent layers; and wherein, after solidification, the support material composition is removed by immersion of the solidified objet with the support in a liquid composition comprising a solvent.

Abstract: A method for forming three-dimensional objects is disclosed. The method includes printing building material, layer by layer, to form a three dimensional object by depositing building material in layers onto a printing tray to form a three dimensional object and maintaining the uppermost layers being deposited in a flowable state by a temperature control after layers below the uppermost layers are solidified.

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.

Abstract: A method for printing three dimensional objects and support compositions are disclosed. The composition includes at least one curable component and at least one non-curable component, the non-curable component being a polyol, a glycol or water, wherein none of said non-curable components is reactive with any of said curable components. The composition has a first viscosity of 20-500 cps at ambient temperature and a second viscosity of less than 20 cps at temperature higher than the ambient temperature. The composition results in a solid, a semi solid or a gel type material after 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.