Multicoloured fused deposition modelling print

Abstract

The invention relates to a modified fused deposition modeling process for production of multicolored three-dimensional objects. More particularly, the invention relates to a 3D printing process with which 3D objects with particularly good color appearance compared to the prior art can be produced. The process according to the invention is based on coloring of the polymer strand used for production of the actual object in the nozzle, and on using a mixing apparatus which comprises a plurality of injection needles, a static mixer or a dynamic mixer.

1 - 21 . (canceled) 
     
     
         22 . A polymer filament printing apparatus, comprising:
 a first print head with which a support material is printed, and a second print head with which a build material is printed, wherein the second print head has a polymer filament feed inlet for feeding the polymer filament into the second print head,   wherein the second print head comprises an outlet nozzle downstream of the polymer filament feed inlet having at least two regions such that the polymer filament is solid in an upper region of the nozzle and molten in a lower region of the outlet nozzle,   wherein the second print head is in fluid connection with a plurality of reservoir vessels each equipped with one or more metering apparatuses, wherein the reservoir vessels hold one or more of an additive and a color ink for supply to the outlet nozzle,   wherein the second print head comprises a mixing apparatus to mix one or more of the additives and the color inks, with the molten polymer filament, and   wherein the mixing apparatus is a dynamic mixer mounted on an outside surface of the print head, and the dynamic mixer is in fluid connection with one or more additives, color inks, or both, and wherein the dynamic mixer forms a mixture that is passed onward into the print head.   
     
     
         23 . The apparatus of  claim 22 , wherein the dynamic mixer is mounted in the nozzle, and the mixture is passed to the filament in the upper region of the outlet nozzle or into a polymer melt in the lower region of the outlet nozzle. 
     
     
         24 . The apparatus of  claim 22 , wherein the dynamic mixer is mounted in the print head above the outlet nozzle, and the mixture is applied to a surface of the filament. 
     
     
         25 . The apparatus of  claim 22 , wherein the print head comprises, in addition to the dynamic mixer, a static mixer in the lower region of the outlet nozzle. 
     
     
         26 . The apparatus of  claim 22 , wherein the additives, the color inks, or both, are injected into a melt in the lower region of the outlet nozzle, metered and distributed by means of micro-injection nozzles which cut into the melt at an angle of 90°. 
     
     
         27 . The apparatus of  claim 22 , wherein the color inks are at least three primary color inks and black, and the inks are each initially charged in a separate reservoir vessel equipped with a metering apparatus. 
     
     
         28 . The apparatus of  claim 22 , further comprising a third print head which is equipped in exactly the same way as the second print head, and has a filament for a second build material. 
     
     
         29 . The apparatus of  claim 28 , wherein the second print head comprises a non-transparent build material uncolored prior to the coloring operation, and the third print head comprises a transparent build material uncolored prior to the coloring operation. 
     
     
         30 . The apparatus of  claim 28 , wherein the second and third print heads each with dedicated mixing apparatuses draw on the same reservoir vessel. 
     
     
         31 . The apparatus of  claim 22 , wherein the build material is a thermoplastic material. 
     
     
         32 . The apparatus of  claim 22 , wherein the build material from the second print head, a third optional print head, or both, comprise at least one selected from the group consisting of acrylonitrile-butadiene-styrene terpolymer (ABS), polycarbonate (PC), poly(meth)acrylate, polyphenylene sulfone (PPSU), HDPE, polyetherimide (PEI), polyetheretherketone (PEEK), and polylactic acid (PLA). 
     
     
         33 . The apparatus of  claim 29 , wherein the build material from the third nozzle is a polymethacrylate or polycarbonate. 
     
     
         34 . The apparatus of  claim 22 , wherein the support material from the first print head is an acid-, base- or water-soluble polymer. 
     
     
         35 . The apparatus of  claim 27 , wherein a respective hue is input into a computer-based CAD program that provides a file which, in addition to coordinates, contains color information for manufacture and for regulation of material and color settings, and hence the respective hue is established by regulation of the metering apparatuses and controlled metering of the respective primary color inks and black ink from the reservoir vessels. 
     
     
         36 . The apparatus of  claim 27 , further comprising further reservoir vessels which, in addition to black and primary colors, comprise further color inks. 
     
     
         37 . The apparatus of  claim 36 , wherein the color ink comprises a metallic pigment. 
     
     
         38 . The apparatus of  claim 36 , wherein the color ink comprises a fluorescent pigment. 
     
     
         39 . The apparatus of  claim 22 , wherein the reservoir vessel comprises an additive activatable by microwaves, heat, UV light or magnetic fields. 
     
     
         40 . The apparatus of  claim 22 , wherein the reservoir vessel comprises an adhesion promoter or adhesive, and the composition is optionally colorless.