The present invention generally relates to methods of printing articles using three-dimensional printing and other printing techniques, and to articles formed from such techniques, including the printing of articles of footwear containing particles. Certain embodiments are generally directed to composites comprising particles (e.g., reinforcing particles), for example, rubber particles. The particles may be used, for example, to increase slip or abrasion resistance. The composites may also contain polyurethanes or other compounds, e.g., to facilitate fabrication, e.g., using three-dimensional printing and other printing techniques. Other embodiments are directed to methods of making or using such articles. For example, in some embodiments, a composite may be prepared by mixing particles (e.g., reinforcing particles) with at least a first fluid and a second fluid within a nozzle, such as a microfluidic printing nozzle, which may be used to direct the resulting product onto a substrate.

The present invention generally relates to methods of printing articles using three-dimensional printing and other printing techniques, and to articles formed from such techniques, including the printing of articles of footwear containing particles. Certain embodiments are generally directed to composites comprising particles (e.g., reinforcing particles), for example, rubber particles. The particles may be used, for example, to increase slip or abrasion resistance. The composites may also contain polyurethanes or other compounds, e.g., to facilitate fabrication, e.g., using three-dimensional printing and other printing techniques. Other embodiments are directed to methods of making or using such articles. For example, in some embodiments, a composite may be prepared by mixing particles (e.g., reinforcing particles) with at least a first fluid and a second fluid within a nozzle, such as a microfluidic printing nozzle, which may be used to direct the resulting product onto a substrate.

Disclosed is direct ink write (DIW) print extrusion head for 3D printing of viscous elastomers. The disclosed print extrusion head comprises a mixer assembly, comprising a fluid distribution cap coupled to a carrier, an in-line mixer coupled to the fluid distribution cap. A cooling jacket surrounds the in-line mixer. A nozzle is coupled to the in-line mixer and protrudes below the cooling jacket over a work surface. The position of the nozzle relative to the work surface is changeable. At least one heat source is on the chassis and disposed adjacent to the fluid distribution cap. The at least one heat source comprises a heat guiding element to direct heat to a region onto the work surface below the nozzle.

Disclosed is direct ink write (DIW) print extrusion head for 3D printing of viscous elastomers. The disclosed print extrusion head comprises a mixer assembly, comprising a fluid distribution cap coupled to a carrier, an in-line mixer coupled to the fluid distribution cap. A cooling jacket surrounds the in-line mixer. A nozzle is coupled to the in-line mixer and protrudes below the cooling jacket over a work surface. The position of the nozzle relative to the work surface is changeable. At least one heat source is on the chassis and disposed adjacent to the fluid distribution cap. The at least one heat source comprises a heat guiding element to direct heat to a region onto the work surface below the nozzle.

A three-dimensional printing method can include iteratively applying polymer build material as individual layers; based on a three-dimensional object model, selectively jetting an electromagnetic radiation absorber and a translucency-modulating plasticizer onto individual layers of the polymer build material; and exposing the powder bed to electromagnetic energy to selectively fuse portions of individual layers of the polymer build material together to form a three-dimensional object. The polymer build material can include from about 60 wt % to 100 wt % polymeric particles having an average particle size from about 10 ?m to about 150 ?m and a degree of crystallinity from about 2% to about 60%, to a powder bed. At the locations where the polymer build material includes jetted translucency-modulating plasticizer, the three-dimensional object can exhibit an optical transmittance from about 5% to about 80%.

A multi-material three-dimensional printing apparatus is provided. The provided apparatus includes two or more print stations. Each of the print stations includes a substrate, a transportation device, a dispersion device, a compaction device, a printing device, a fixing device, and a fluidized materials removal device. The apparatus also includes an assembly apparatus in communication with the two or more print stations via the transportation device. The apparatus also includes one or more transfer devices in communication with the assembly apparatus. The apparatus also includes a computing and controlling device configured to control the operations of the two or more print stations, the assembly apparatus and the one or more transfer devices.

A multi-material three-dimensional printing apparatus is provided. The provided apparatus includes two or more print stations. Each of the print stations includes a substrate, a transportation device, a dispersion device, a compaction device, a printing device, a fixing device, and a fluidized materials removal device. The apparatus also includes an assembly apparatus in communication with the two or more print stations via the transportation device. The apparatus also includes one or more transfer devices in communication with the assembly apparatus. The apparatus also includes a computing and controlling device configured to control the operations of the two or more print stations, the assembly apparatus and the one or more transfer devices.

An extruder of a three-dimensional printer may be coupled with one or more filament tubes, each filament tube having its own supply of filament. The extruder may include a drive gear rotatable in a first direction to advance a filament from a filament tube toward at least one extrusion opening defined by the extruder and rotatable in a second direction, opposite the first direction, to advance another filament from a different filament tube toward the at least one extrusion opening defined by the extruder. Also, as one filament is advanced by the drive gear, another filament may be retracted by the drive gear to improve the switching of filaments in a three-dimensional printing process. The extruder may work in conjunction with a filament supply-side drive system that feeds filament into one or more filament tubes, reducing a pull force exerted by the drive gear of the extruder.

An extruder of a three-dimensional printer may be coupled with one or more filament tubes, each filament tube having its own supply of filament. The extruder may include a drive gear rotatable in a first direction to advance a filament from a filament tube toward at least one extrusion opening defined by the extruder and rotatable in a second direction, opposite the first direction, to advance another filament from a different filament tube toward the at least one extrusion opening defined by the extruder. Also, as one filament is advanced by the drive gear, another filament may be retracted by the drive gear to improve the switching of filaments in a three-dimensional printing process. The extruder may work in conjunction with a filament supply-side drive system that feeds filament into one or more filament tubes, reducing a pull force exerted by the drive gear of the extruder.

A method for operating the 3D printing tool includes positioning a first material distribution barrel within a first barrel orifice, where a first barrel tip is disposed at a first end of the first material distribution barrel. The method further includes positioning a second material distribution barrel within a second barrel orifice, where a second barrel tip is disposed at a first end of the second material distribution barrel. The method further includes dispensing building material from the first material distribution barrel when the first material distribution barrel is substantially vertically oriented and a second material distribution barrel is oriented at an angle from the vertical.