Method to add color to a part during 3D printing and 3d printing method

专利摘要:
In an example of a three-dimensional printing method, a polymeric building material is applied. A melting agent is selectively applied to at least a portion of the polymeric building material. The melting agent includes cesium-tungsten oxide nanoparticles, a zwitterionic stabilizer, and an aqueous carrier. The polymeric building material is exposed to electromagnetic radiation to fuse the portion of the polymeric building material in contact with the melting agent to form a layer.
公开号:BR112018015540B1
申请号:R112018015540-3
申请日:2016-10-25
公开日:2022-02-01
发明作者:Stephen G. Rudisill；Vladek Kasperchik；Alexey S. Kabalnov；Shannon Woodruff；Thomas M. Sabo；Jake WRIGHT；Hector Lebron；Vanessa Verzwyvelt；Morgan T. Schramm；Matthew A. Shepherd
申请人:Hewlett-Packard Development Company, L.P；
IPC主号:

专利说明:

FUNDAMENTALS
[001] Three-dimensional (3D) printing can be an additive printing process used to make solid three-dimensional parts from a digital model. 3D printing is often used in rapid product prototyping, mold generation, and mold master generation. Some 3D printing techniques are considered additive processes because they involve the application of successive layers of material. This is different from traditional machining processes, which often rely on material removal to create the final part. Materials used in 3D printing often require curing or melting, which for some materials can be accomplished using heat-assisted extrusion or sintering, and for other materials can be accomplished using digital light projection technology. BRIEF DESCRIPTION OF THE DRAWINGS
[002] Features of the examples of the present disclosure will become apparent by reference to the following detailed description and drawings, in which like reference numerals correspond to similar, though perhaps not identical, components. For the sake of brevity, reference numbers or features having a previously described function may or may not be described in connection with other drawings in which they appear. Figure 1 is a simplified isometric view of an example 3D printing system; Figure 2 is a flowchart illustrating an example of a 3D printing method; Figure 3 is a cross-sectional view of an example of a part formed using an example of the 3D printing method described herein; Figures 4A to 4H are schematic views depicting the formation of a part using an example of the 3D printing method described herein; Figure 5 is a flowchart illustrating another example of a 3D printing method; and Figures 6A to 6D are schematic views depicting the formation of a part using another example of the 3D printing method described herein. DETAILED DESCRIPTION
[003] Examples of the three-dimensional (3D) printing method and 3D printing system described here use Multiple Jet Fusion (MJF). During multi-jet melting, an entire layer of building material (also known as building material particles) is exposed to radiation, but a selected region (in some cases smaller than the entire layer) of building material is fused and hardened to become a layer of a 3D part. A melting agent is selectively deposited in contact with the selected region of the building material. The melting agent(s) is capable of penetrating the layer of building material and spreading on the outer surface of the building material. This melting agent is capable of absorbing radiation and converting the absorbed radiation into thermal energy, which in turn melts or sinters the building material that is in contact with the core melting agent. This causes the building material to melt, bind, heal, etc. to form the 3D part layer.
[004] Melting agents used in multi-jet melting tend to have significant absorption (eg, 80%) in the visible region (400 nm - 780 nm). In the examples disclosed herein, this melting agent is referred to as the core melting agent, or, in some cases, the black melting agent. This absorption generates heat suitable for fusion during 3D printing, which leads to 3D parts having mechanical integrity and relatively uniform mechanical properties (e.g. strength, elongation at break, etc.). This absorption, however, also results in strongly colored 3D parts, for example black.
[005] Some examples of the method and system disclosed herein use an example of a low-tone melting agent (also referred to herein as "melting agent" and "primer melting agent") instead of the core melting agent to build every 3D part. This example of the low-tone melting agent includes stabilized cesium tungsten oxide (CTO) nanoparticles. CTO nanoparticles are plasmonic resonance absorbers, having absorption at wavelengths ranging from 800 nm to 4000 nm and transparency at wavelengths ranging from 400 nm to 780 nm. As used herein, "absorption" means that at least 80% of radiation having wavelengths ranging from 800 nm to 4000 nm is absorbed. Also used herein, "transparency" means that 20% or less of radiation having wavelengths ranging from 400 nm to 780 nm is absorbed. This absorption and transparency allows the low-tone melting agent to absorb enough radiation to melt the building material in contact with it while making the 3D part white or lightly colored.
[006] Other examples of the method and system disclosed herein utilize a combination of different melting agents (e.g., the above-mentioned core melting agent and low pitch melting agent or other low pitch melting agent) to build a part having a core (layers or innermost region) with mechanical integrity and having an exterior (layers or outermost region) with color (i.e. white or some color other than black). The agent(s) applied will depend on whether the layer or portion of the layer is to improve mechanical properties or to be color-focused.
[007] Referring now to Figure 1, an example of a 3D printing system 10 is represented. It should be understood that the 3D printing system 10 may include additional components and that some of the components described herein may be removed and/or modified. In addition, the components of the 3D printing system 10 depicted in Figure 1 may not be drawn to scale, and thus the 3D printing system 10 may have a different size and/or configuration than those illustrated therein.
[008] The printing system 10 includes a building area platform 12, a building material supply 14 containing building material particles 16 and a building material dispenser 18.
[009] The build area platform 12 receives the building material particles 16 from the building material supply 14. The build area platform 12 can be integrated with the printing system 10 or it can be a component that can be inserted separately into the printing system 10. For example, the building area platform 12 can be a module that is available separately from the printing system 10. The building material platform 12 which is shown is also an example , and could be replaced by another support member, such as a plate, a print/fabrication bed, a glass plate, or other construction surface.
[0010] The building area platform 12 can be moved in a direction as denoted by the arrow 20, for example along the z axis, so that the building material particles 16 can be delivered to the platform 12 or to a layer preformed part (see, for example, Figure 4D). In one example, when building material particles 16 are delivered, the building area platform 12 can be programmed to advance (e.g., downwards) far enough that the building material dispenser 18 can push the building material particles. building material 16 to the platform 12 to form a substantially uniform layer of building material particles 16 thereon (see, for example, Figures 4A and 6A). The build area platform 12 can also be returned to its original position, for example when a new part is to be built.
[0011] The building material supply 14 may be a container, bed or other surface which is for positioning the building material particles 16 between the building material dispenser 18 and the building area platform 12. In some examples , the building material supply 14 may include a surface onto which the building material particles 16 can be supplied, for example from a building material source (not shown) located above the building material supply 14. Examples of the source of construction material may include a hopper, an auger conveyor, or the like. Additionally, or alternatively, the building material supply 14 may include a mechanism (e.g., a delivery piston) for providing, for example, moving the building material particles 16 from a storage location to a to be spread on the build area platform 12 or on a layer of pre-formed part.
[0012] The building material dispenser 18 can be moved in one direction as indicated by the arrow 22, for example along the y-axis, over the building material supply 14 and across the building area platform 12 to spread a layer of the building material particles 16 on the building area platform 12. The building material dispenser 18 can also be returned to a position adjacent to the building material supply 14 following the scattering of the building material particles 16 The building material distributor 18 may be a blade (e.g. a scraper blade), a roller, a combination of a roller and a blade, and/or any other device capable of spreading the building material particles 16. on the building area platform 12. For example, the building material dispenser 18 may be a counter-rotating roller.
[0013] The building material particles 16 may be a polymeric building material. As used herein, the term "polymeric building material" may refer to crystalline or semi-crystalline polymer particles or composite particles comprised of polymer and ceramic. Any of the particles 16 may be in powder form. Examples of semi-crystalline polymers include semi-crystalline thermoplastic materials with a wide processing window greater than 5°C (i.e., the temperature range between the melting point and the recrystallization temperature). Some specific examples of semi-crystalline thermoplastic materials include polyamides (PAs) (e.g. PA 11 / nylon 11, PA 12 / nylon 12, PA 6 / nylon 6, PA 8 / nylon 8, PA 9 / nylon 9, PA 66 / nylon 66, PA 612 / nylon 612, PA 812 / nylon 812, PA 912 / nylon 912, etc.). Other examples of crystalline or semicrystalline polymers suitable for use as particles of building material 16 include polyethylene, polypropylene, and polyoxomethylene (i.e., polyacetals). Still other examples of suitable building material particles 16 include polystyrene, polycarbonate, polyester, polyurethanes, other engineering plastics and blends of any two or more polymers listed herein.
[0014] Any of the crystalline or semi-crystalline polymer particles listed above can be combined with ceramic particles to form the composite particles. Examples of suitable ceramic particles include metal oxides, inorganic glasses, carbides, nitrides and borides. Some specific examples include alumina (Al2O3), glass, silicon mononitride (SiN), silicon dioxide (SiO2), zirconium (ZrO2), titanium dioxide (TiO2), or combinations thereof. The amount of ceramic particles that can be combined with the crystalline or semi-crystalline polymer particles may depend on the materials used and the 3D part to be formed. In one example, the ceramic particles may be present in an amount ranging from about 1% by weight to about 20% by weight, based on the total weight % of the building material particles 16.
[0015] The building material particles 16 may have a melting point or a softening point ranging from about 50°C to about 400°C. As an example, the building material particles 16 may be a polyamide with a melting point of 180°C.
[0016] The particles of building material 16 can be made of particles of similar size or particles of different sizes. The term "size", as used herein in connection with the particles of building material 16, refers to the diameter of a spherical particle, or the average diameter of a non-spherical particle (i.e., the average of multiple diameters across the particle) , or the volume-weighted average diameter of a particle distribution. In one example, the average particle size of building material 16 ranges from 5 μm to about 200 μm.
[0017] As shown in Figure 1, the printing system 10 also includes an inkjet applicator 24A, which may contain examples of the melting agent 26 or 26' (i.e., the primer or low-tone melting agent). ).
[0018] Melting agents 26, 26' generally include an aqueous or non-aqueous vehicle and a plasmon resonance absorber dispersed therein. The 26' melting agent is a specific example of the primer or low tone melting agent, which includes CTO nanoparticles as the plasmon resonance absorber, a zwitterionic stabilizer, and an aqueous carrier.
[0019] As mentioned above, the fusion agent 26 includes the plasmon resonance absorber. The plasmon resonance absorber allows the melting agent 26 to absorb radiation at wavelengths between 800 nm and 4000 nm, which allows the melting agent 26 to convert enough radiation into thermal energy for the building material particles 16 to melt. found. The plasmon resonance absorber also allows the melting agent 26 to have transparency at wavelengths ranging from 400 nm to 780 nm, which allows the 3D part 38 to be white or lightly colored.
[0020] The absorption of the plasmon resonance absorber is the result of plasmon resonance effects. Electrons associated with the atoms of the plasmonic resonance absorber can be collectively excited by electromagnetic radiation, which results in a collective oscillation of the electrons. The wavelengths needed to excite and oscillate these electrons collectively are dependent on the number of electrons present in the plasmon resonance absorber particles, which in turn is dependent on the size of the plasmon resonance absorber particles. The amount of energy required to collectively oscillate the particle's electrons is low enough that very small particles (e.g. 1-100 nm) can absorb electromagnetic radiation with wavelengths several times (e.g. 8 to 800 or more times) the size of the particles. The use of these particles allows the melting agent 26 to be ink jet blasted as well as electromagnetically selective (e.g. having absorption at wavelengths between 800 nm and 4000 nm and transparency at wavelengths between 400 nm and 780 nm). nm).
[0021] In one example, the plasmon resonance absorber has an average particle diameter (eg volume weighted average diameter) ranging from greater than 0 nm to less than 220 nm. In another example, the plasmon resonance absorber has an average particle diameter ranging from greater than 0 nm to 120 nm. In yet another example, the plasmon resonance absorber has an average particle diameter ranging from about 10 nm to about 200 nm.
[0022] In one example, the plasmon resonance absorber is an inorganic pigment. Examples of suitable inorganic pigments include lanthanum hexaboride (LaB6), tungsten bronzes (AxWO3), indium tin oxide (In2O3: SnO2, ITO), aluminum zinc oxide (AZO), ruthenium oxide (RUO2), silver (Ag), gold (Au), platinum (Pt), iron pyroxenes (AxFeySi2O6 where A is Ca or Mg, x = 1.5-1.9 and y = 0.1-0.5), iron phosphates modified (AxFeyPO4), and modified copper pyrophosphates (AxCuyP2O7). Tungsten bronzes can be alkali-doped tungsten oxides. Examples of suitable alkaline dopants (i.e. A in AxWO3 ) can be cesium, sodium, potassium or rubidium. In one example, the alkali-doped tungsten oxide can be doped in an amount ranging from greater than 0 mole % to about 0.33 mole % based on the total mole % of the alkali-doped tungsten oxide. Suitable modified iron phosphates (AxFeyPO4) may include copper-iron phosphate (A=Cu, x=0.1-0.5 and y=0.5-0.9), magnesium-iron phosphate (A=Mg, x = 0.1 -0.5, and y = 0.5-0.9) and zinc-iron phosphate (A = Zn, x = 0.1 -0.5 and y = 0.5-0.9) . For modified iron phosphates, it should be understood that the number of phosphates can change based on the charge balance with the cations. Suitable modified copper pyrophosphates (AxCuyP2O7) include iron-copper pyrophosphate (A = Fe, x = 0-2 and y = 0-2), magnesium-copper pyrophosphate (A = Mg, x = 0-2 and y = 0- 2) and zinc-copper pyrophosphate (A = Zn, x = 02 and y = 0-2). Inorganic pigment combinations can also be used.
[0023] The amount of plasmon resonance absorber that is present in the melting agent 26 varies from about 1.0% by weight to about 20.0% by weight based on the % by total weight of the melting agent 26. In some examples, the amount of the plasmon resonance absorber present in the melting agent 26 ranges from about 1.0% by weight to about 10.0% by weight. In other examples, the amount of the plasmon resonance absorber present in the melting agent 26 ranges from greater than 4.0% by weight to about 15.0% by weight. These plasmon resonance absorber charges are believed to provide a balance between the melting agent 26 having blasting reliability and electromagnetic radiation absorption efficiency.
[0024] As used herein, "AF vehicle" can refer to the liquid fluid in which the plasmon resonance absorber is placed to form the melting agent 26. A wide variety of FA vehicles can be used, including aqueous vehicles and non-aqueous, with the plasmon resonance absorber. In some cases, the FA vehicle includes only water or a non-aqueous solvent (e.g., dimethyl sulfoxide (DMSO), ethanol, etc.) alone. In other cases, the FA carrier may further include a dispersion additive, a surfactant, a co-solvent, a biocide (i.e., antimicrobial), an anti-kogation agent, a silane coupling agent, a chelating agent, and their combinations.
[0025] When the FA carrier is water-based, the aqueous nature of the melting agent 26 allows the melting agent 26 to at least partially penetrate the layer of building material particles 16. The building material particles Construct 16 may be hydrophobic, and the presence of the co-solvent, surfactant, and/or dispersion additive in the melting agent 26 when the melting agent 26 is water-based or non-aqueous, can help to achieve melting behavior. particular humidification.
[0026] The plasmon resonance absorber in the melting agent 26 may, in some cases, be dispersed with a dispersion additive. As such, the dispersion additive helps to evenly distribute the plasmon resonance absorber throughout the melting agent 26. As mentioned above, the dispersion additive can also aid in the wetting of the melting agent 26 in the building material particles 16. Some examples of the additive dispersion include a water-soluble acrylic acid polymer (e.g. CARBOSPERSE® K7028 available from Lubrizol), an acrylic-styrene pigment dispersion resin (e.g. JONCRYL® 671 available from BASF Corp. .), a high molecular weight block copolymer with pigment affinic groups (eg, DISPERBYK®-190 available from BYK Additives and Instruments) and combinations thereof. Whether a single dispersion additive is used or a combination of dispersion additives is used, the total amount of dispersion additive(s) in the melting agent 26 can range from about 10% by weight to about 200% by weight with based on % by weight of the plasmon resonance absorber in the melting agent 26.
[0027] The surfactant(s) can also be used in the FA vehicle to improve the wetting properties of the melting agent 26. Examples of suitable surfactants include non-ionic surfactants. Some specific examples include a self-emulsifying nonionic wetting agent based on acetylenic diol chemistry (e.g. SURFYNOL® SEF from Air Products and Chemicals, Inc.), a nonionic fluorosurfactant (e.g. CAPSTONE® fluorosurfactants from DuPont, formerly known as ZONYL FSO) and their combinations. In other examples, the surfactant is an ethoxylated low foam wetting agent (e.g. SURFYNOL® 440 or SURFYNOL® CT-11 from Air Products and Chemical Inc.) or an ethoxylated wetting agent and molecular defoamer (e.g. SURFYNOL® 420 from Air Products and Chemical Inc.). Still other suitable surfactants include nonionic wetting agents and molecular defoamers (e.g. SURFYNOL® 104E from Air Products and Chemical Inc.) or water-soluble nonionic surfactants (e.g. TERGITOL™ TMN-6, TERGITOL™ 15S7 and TERGITOL™ 15S9 from The Dow Chemical Company). In some examples, an anionic surfactant may be used in combination with the nonionic surfactant. A suitable anionic surfactant is an alkyldiphenyloxide disulfonate (eg DOWFAX™ 8390 and DOWFAX™ 2A1 from The Dow Chemical Company). In some examples, it may be desirable to use a surfactant with a hydrophilic-lipophilic balance (HLB) of less than 10.
[0028] Whether a single surfactant is used or a combination of surfactants is used, the total amount of surfactant(s) in the melting agent 26 can range from about 0.1% by weight to about 4% by weight based on in the % by total weight of the melting agent 26.
[0029] Some examples of the co-solvent that can be added to the FA vehicle include 1-(2-hydroxyethyl)-2-pyrolidinone, 2-pyrrolidinone, 1,5-pentanediol, triethylene glycol, tetraethylene glycol, 2-methyl-1, 3-propanediol, 1,6-hexanediol, tripropylene glycol methyl ether and combinations thereof. Whether a single co-solvent is used or a combination of co-solvents is used, the total amount of co-solvent(s) in the melting agent 26 can range from about 2% by weight to about 80% by weight by weight. with respect to the % by total weight of the melting agent 26.
[0030] A biocide or antimicrobial may be added to the melting agent 26. Examples of suitable biocides include an aqueous solution of 1,2-benzisothiazolin-3-one, quaternary ammonium compounds (e.g., BARDAC® 2250 and 2280, BARQUAT ® 50-65B and CARBOQUAT® 250-T, all from Lonza Ltd. Corp.), an aqueous solution of methylisothiazolone, NUOSEPT® (Ashland Inc.), VANCIDE® (RT Vanderbilt Co.), ACTICIDE® B20 and ACTICIDE® M20 (Thor Chemicals). Whether a single biocide is used or a combination of biocides is used, the total amount of biocide(s) in the melting agent 26 can range from about 0.1% by weight to about 1% by weight based on % by weight. total fusing agent 26.
[0031] An anti-kogation agent may be included in the fusing agent 26. Kogation refers to depositing dry ink (eg, fusing agent 26) on a heating element of a thermal inkjet print head . The anti-kogation agent(s) is included to assist in preventing the accumulation of kogation. Examples of suitable anti-caking agents include oleth-3-phosphate (for example, commercially available as CRODAFOS™ O3A or CRODAFOS™ N-3 acid from Croda), or a combination of oleth-3-phosphate and an acrylic acid polymer of low molecular weight (e.g. < 5000) (e.g. commercially available as CARBOSPERSE™ Polyacrylate K-7028 from Lubrizol). Whether a single anti-kogation agent is used or a combination of anti-cogation agents is used, the total amount of anti-kogation agent(s) in the fusion agent 26 can range from about 0.1% by weight to about 0.2% by weight on the % by total weight of the melting agent 26.
[0032] A silane coupling agent can be added to the melting agent 26 to help bond the organic and inorganic materials together. Examples of suitable silane coupling agents include SILQUEST® A series manufactured by Momentive.
[0033] If a single silane coupling agent is used or a combination of silane coupling agents is used, the total amount of silane coupling agent(s) in the melting agent 26 can vary from about 0.1 % to about 50% based on the % by weight of the plasmon resonance absorber in the melting agent 26. In one example, the total amount of silane coupling agent(s) in the melting agent 26 ranges from about 1% by weight to about 30% by weight based on the % by weight of the plasmon resonance absorber. In another example, the amount of total silane coupling agent(s) in the melting agent 26 ranges from about 2.5% by weight to about 25% by weight based on the % by weight of the plasmon resonance absorber.
[0034] The melting agent 26 may also include other additives, such as a chelating agent. The chelating agent may be included to eliminate the harmful effects of heavy metal impurities. Examples of suitable chelating agents include disodium ethylenediaminetetraacetic acid (EDTA-Na), ethylenediaminetetraacetic acid (EDTA), and methylglycine acetic acid (e.g., TRILON® M from BASF Corp.). Whether a single chelating agent is used or a combination of chelating agents is used, the total amount of chelating agent(s) in the melting agent 26 can range from 0% by weight to about 2% by weight based on % by weight. total melting agent 26. Yet another suitable additive for melting agent 26 is a wetting agent and lubricant (e.g., LIPONIC® EG-1 (LEG-1) from Lipo Chemicals).
[0035] The equilibrium melting agent 26 is water or the non-aqueous solvent.
[0036] As mentioned above, the 26' melting agent is a specific example of the low shade or primer melting agent. The 26' fusion agent includes CTO nanoparticles as the plasmon resonance absorber, a zwitterionic stabilizer and an aqueous carrier.
[0037] CTO nanoparticles in melting agent 26' have a general formula of CsxWO3, where 0 < x < 1. Cesium tungsten oxide nanoparticles can give melting agent 26' a light blue color. The color intensity may depend, at least in part, on the amount of CTO nanoparticles in the 26' melting agent. When it is desirable to form an outer white layer on the 3D part, fewer CTO nanoparticles can be used in the 26' melting agent to achieve the white color. In one example, the CTO nanoparticles may be present in the melting agent 26' in an amount ranging from about 1% by weight to about 20% by weight (based on the % by total weight of the melting agent 26') .
[0038] The average particle size (eg volume weighted average diameter) of CTO nanoparticles can range from about 1 nm to about 40 nm. In some examples, the average particle size of the CTO nanoparticles can range from about 1 nm to about 15 nm or from about 1 nm to about 10 nm. The higher end of the particle size range (e.g., from about 30 nm to about 40 nm) may be less desirable, as these particles may be more difficult to stabilize.
[0039] The 26' melting agent also includes the zwitterionic stabilizer. The zwitterionic stabilizer can improve the stabilization of the 26' melting agent. While the zwitterionic stabilizer has an overall neutral charge, at least one area of the molecule has a positive charge (eg amine groups) and at least one other area of the molecule has a negative charge. CTO nanoparticles can have a slight negative charge. The zwitterionic stabilizer molecules can orient around the slightly negative CTO nanoparticles with the positive area of the zwitterionic stabilizer molecules closer to the CTO nanoparticles and the negative area of the zwitterionic stabilizer molecules further away from the CTO nanoparticles. So, the negative charge of the negative area of the zwitterionic stabilizer molecules can repel the CTO nanoparticles from each other. Zwitterionic stabilizer molecules can form a protective layer around CTO nanoparticles, preventing them from coming into direct contact with each other and/or increasing the distance between particle surfaces (e.g. by a distance of about 1 nm to about 2 nm). Thus, the zwitterionic stabilizer can prevent the CTO nanoparticles from agglomerating and/or settling in the 26' fusion agent.
[0040] Examples of suitable zwitterionic stabilizers include C2 to C8 betaines, C2 to C8 aminocarboxylic acids having a solubility of at least 10 g in 100 g of water, taurine and combinations thereof. Examples of the C2 to C8 aminocarboxylic acids include beta-alanine, gamma-aminobutyric acid, glycine and combinations thereof.
[0041] The zwitterionic stabilizer may be present in the melting agent 26' in an amount ranging from about 2% by weight to about 35% by weight (based on the % by total weight of the melting agent 26'). When the zwitterionic stabilizer is C2 to C8 betaine, the C2 to C8 betaine may be present in an amount ranging from about 8% by weight to about 35% by weight of a % by total weight of the melting agent 26'. When the zwitterionic stabilizer is C2 to C8 aminocarboxylic acid, the C2 to C8 aminocarboxylic acid may be present in an amount ranging from about 2% by weight to about 20% by weight of a % by total weight of the melting agent. '. When the zwitterionic stabilizer is taurine, taurine may be present in an amount ranging from about 2% by weight to about 35% by weight of a % by total weight of the melting agent 26'.
[0042] In one example, the weight ratio of the CTO nanoparticles to the zwitterionic stabilizer ranges from 1:10 to 10:1. In another example, the weight ratio of the CTO nanoparticles to the zwitterionic stabilizer is 1:1.
[0043] In one example, the melting agent 26' also includes an aqueous vehicle, which includes a surfactant and a water balance. In another example, the aqueous vehicle of the melting agent 26' includes a co-solvent, a surfactant and a water balance. Any of the above-described co-solvents and/or surfactants for melting agent 26 may be used in melting agent 26' in the respective amounts described above, except % by weight relative to % by total weight of melting agent 26 '. The melting agent 26' may also include a humectant and lubricant.
[0044] In some examples, the melting agent 26' may also include an additive selected from the group consisting of an anti-caking agent, a chelating agent, a biocide, or a combination thereof. Any of the anti-kinking agents, chelating agents and/or biocides previously described for the fusion agent 26 can be used in the fusion agent 26'. Although the amount of the additive may vary depending on the type of additive, generally the additive may be present in the melting agent 26' in an amount ranging from about 0.01% by weight to about 20% by weight (based on % by total weight of the melting agent 26'). As specific examples, the respective amounts of the anti-caking agents, chelating agents and/or biocides previously described for the melting agent 26 may be used in the melting agent 26', except that the % by weight is with respect to the % by weight total fusing agent 26'.
[0045] In some examples disclosed herein, the melting agent 26' may also include additional dispersant(s) (e.g. a low molecular weight (e.g. < 5000) polyacrylic acid polymer such as CARBOSPERSE™ K-7028 Lubrizol Polyacrylate), preservative(s), blast capacity additive(s) and the like.
[0046] It should be understood that the CTO nanoparticles can be added to the other components (including the zwitterionic stabilizer) to form the 26' melting agent. In another example, the CTO nanoparticles may be present in a cesium-tungsten oxide nanoparticle dispersion (including the zwitterionic stabilizer), which is a separate dispersion that is added to the other components to form the 26' melting agent.
[0047] As illustrated in Figure 1, some examples of the printing system 10 may include at least one additional inkjet applicator 24B and/or 24C. In one example, printing system 10 includes inkjet applicator 24B, which may contain a core melting agent 28, in addition to inkjet applicator 24A. In another example, printing system 10 includes inkjet applicator 24C, which may contain colored inkjet ink 30, in addition to inkjet applicator 24A. In yet another example, the printing system 10 includes inkjet applicators 24B and 24C, in addition to inkjet applicator 24A.
[0048] Examples of the core melting agent 28 are water-based dispersions including a radiation absorbing agent (i.e., an active material). The amount of active material in the core melting agent 28 may depend on how absorbent the active material is. In one example, the core melting agent 28 may include the active material and may be applied in an amount sufficient to include at least 0.01% by weight of the active material in the layer of the 3D part that is formed with the melting agent. of core 28. Even this small amount can produce a black colored part layer.
[0049] The active material in the core melting agent 28 can be any infrared light absorbing dye that is black. As such, the core melting agent 28 may be referred to herein as the black melting agent 28. In one example, the active material is an absorber of near infrared light. Any near-infrared black dyes produced by Fabricolor, Eastman Kodak or Yamamoto can be used in Core Fusing Agent 28.
[0050] As an example, the core melting agent 28 may be an ink formulation including carbon black as the active material. Examples of this ink formulation are commercially known as CM997A, 516458, C18928, C93848, C93808 or the like, all available from HP Inc. As another example, the core melting agent 28 can be an ink formulation including near infrared absorbing dyes as the active material.
[0051] Core Melting Agent 28 is an aqueous formulation (i.e., includes a balance of water) that may also include any of the previously listed co-solvents, nonionic surfactant(s), biocide(s), and /or anti-cogation agent(s). In an example of the core melting agent 28, the co-solvent(s) is/are present in an amount ranging from about 1% by weight to about 60% of the total % of the agent 28, the surfactant(s) nonionic is/are present in an amount ranging from about 0.5% by weight to about 1.5% by weight based on the total weight % of the agent 28, the biocide(s) is/are present in a amount ranging from about 0.1% by weight to about 5% by weight based on the % by total weight of the agent 28 and/or the anti-caking agent(s) is/are present in an amount ranging from about 0.1% by weight to about 5% by weight based on the total weight % of agent 28.
[0052] Some examples of the core melting agent 28 may also include a pH adjuster, which is used to control the pH of the agent 28. From 0% by weight to about 2% by weight (from the total weight % of the core melting agent 28) of the pH adjuster, for example, can be used.
[0053] Color inkjet ink 30 includes a colorant, a dispersion/dispersant additive, a co-solvent, and water. In some cases, color inkjet ink 30 includes these components and no other components. In other cases, the color inkjet ink 30 may further include an anti-caking agent, a biocide, a binder, and combinations thereof.
[0054] Color inkjet ink dye 30 is a pigment and/or dye having a color other than white. Examples of the other colors include cyan, magenta, yellow, black, etc. In some cases, the dye in color ink 34 may also be transparent to infrared wavelengths. Examples of clear IR dyes include acid yellow 23 (AY 23), AY17, acid red 52 (AR 52), AR 289 and reactive red 180 (RR 180). In other cases, the color inkjet ink dye 30 may not be completely transparent at infrared wavelengths, but does not absorb sufficient radiation to sufficiently heat the particles of building material in contact therewith. For example, the dye in color inkjet ink 30 can absorb some visible wavelengths and some IR wavelengths. Some examples of these dyes include cyan dyes such as direct blue 199 (DB 199) and pigment blue 15:3 (PB 15:3).
[0055] The color inkjet ink 30 also includes the dispersion additive, which helps to evenly distribute the dye throughout the color inkjet ink 30 and aids in wetting the ink 30 on the building material particles 16. Any one of the dispersion additives discussed herein for the melting agent 26 may be used in the color inkjet ink 30. The dispersion additive may be present in the color inkjet ink 30 in an amount similar to the dye.
[0056] In addition to the non-white dye and dispersion additives, the color inkjet ink 30 may include components similar to the melting agent 26 (e.g., co-solvent(s), anti-kogation agent(s), biocide(s), water, etc.). The color inkjet ink 30 may also include a binder, such as an acrylic latex binder, which may be a copolymer of any two or more of styrene, acrylic acid, methacrylic acid, methyl methacrylate, ethyl methacrylate, and butyl methacrylate. Some examples of color inkjet ink 30 may also include other additives such as a humectant and lubricant (e.g. LIPONIC® EG-1 (LEG-1) from Lipo Chemicals), a chelating agent (e.g. disodium ethylenediaminetetraacetic acid (EDTA-Na)) and/or a buffer.
[0057] An example of the pigment-based color inkjet ink 30 may include from about 1% by weight to about 10% by weight of pigment(s), from about 10% by weight to about 30 % by weight of co-solvent(s), from about 1% by weight to about 10% by weight of dispersion additive(s), from 0.01% by weight to about 1% by weight of anti-caking agent(s), from about 0.1% by weight to about 5% by weight of binder(s), from about 0.05% by weight to about 0.1% by weight of biocide(s), and a water balance. An example of the dye-based color inkjet ink 30 may include from about 1% by weight to about 7% by weight of dye(s), from about 10% by weight to about 30% by weight of co-solvent(s), from about 1% by weight to about 7% by weight of dispersion additive(s), from about 0.05% by weight to about 0.1% by weight of agent(s) chelator, from about 0.005% by weight to about 0.2% by weight of buffer(s), from about 0.05% by weight to about 0.1% by weight of biocide(s), and a water balance.
[0058] Some examples of color inkjet ink 30 include a set of cyan, magenta and yellow inks such as C1893A (cyan), C1984A (magenta) and C1985A (yellow); or C4801A (cyan), C4802A (magenta), and C4803A (yellow); all of which are available from the Hewlett-Packard Company. Other commercially available color inks include C9384A (HP 72 Printhead), C9383A (HP 72 Printhead), C4901A (HP 940 Printhead), and C4900A (HP 940 Printhead).
[0059] The inkjet applicator(s) 24A, 24B, 24C may be swept across the build area platform 12 in the direction indicated by arrow 32, for example along the y-axis. The inkjet applicators 24A, 24B, 24C can be, for example, a thermal inkjet print head, a piezoelectric print head, etc., and can extend the width of the build area platform 12. While each of the inkjet applicator(s) 24A, 24B, 24C is shown in Figure 1 as a single applicator, it is to be understood that each of the inkjet applicator(s) 24A, 24B, 24C may include multiple inkjet applicators that span the width of the build area platform 12. In addition, the inkjet applicator(s) 24A, 24B, 24C can be positioned on multiple print bars. The inkjet applicator(s) 24A, 24B, 24C may also be swept along the x-axis, for example, in configurations in which the inkjet applicator(s) 24A, 24B, 24C do not span the width of the build area platform 12 to allow inkjet applicator(s) 24A, 24B, 24C to respectively deposit fusing agent 26 or 26', core fusing agent 28 and color ink jet ink 30 over a large area of a layer of building material particles 16. The inkjet applicator(s) 24A, 24B, 24C can thus be attached to a moving XY stage or a translation carriage (none of which is shown) which moves the inkjet applicator(s) 24A, 24B, 24C adjacent the build area platform 12 to deposit respective fluids 26 or 26', 28 and 30 in predetermined areas of a layer of the building material particles. construction 16 which have been formed on the construction area platform 12 according to the method(s) here described. The inkjet applicator(s) 24A, 24B, 24C may include a plurality of nozzles (not shown) through which fluids 26 or 26', 28 and 30 are respectively to be ejected.
[0060] Although not shown in Figure 1, the printing system 10 may also include another inkjet applicator (not shown), which may contain a detailing agent (42, see Figure 4H). This other inkjet applicator is similar to inkjet applicators 24A, 24B, 24C and can be configured in any manner described herein with reference to inkjet applicators 24A, 24B, 24C.
[0061] Detailing agent 42 can be used for thermal management of building material particles 16 that are not to be melted. The detailing agent 42 can be just water. The detailing agent 42 may also include a surfactant and/or a co-solvent. In some examples, the verbose agent 42 consists of these components, and no other components. In other examples, detailing agent 42 further includes an anti-caking agent, a biocide, or combinations thereof. The components of the detailing agent 34 may be similar to the surfactants, co-solvents, anti-caking agents, and biocide described herein with reference to the melting agent 26, 26' and/or the core melting agent 28.
[0062] Inkjet applicators 24A, 24B, 24C can respectively deliver drops of melting agent 26 or 26', core melting agent 28 and color inkjet ink 30 (or detailing agent 42 ) at a resolution ranging from about 300 dots per inch (DPI) to about 1200 DPI. In other examples, the applicator(s) 24A, 24B, 24C may drop drops of the respective fluids 26 or 26', 28 and 30 at a higher or lower resolution. The droplet velocity can range from about 5 m/s to about 24 m/s and the trigger frequency can range from about 1 kHz to about 100 kHz. In one example, each drop may be on the order of about 10 picoliters (pl) per drop, although it is contemplated that a larger or smaller droplet size could be used. In some examples, inkjet applicators 24A, 24B, 24C are capable of delivering variable size droplets of fluids 26 or 26', 28 and 30, respectively.
[0063] Each of the physical elements described above can be operatively connected to a controller 34 of the printing system 10. The controller 34 can control the operations of the building area platform 12, the supply of building material 14, the distributor of building material 18, and inkjet applicator(s) 24A, 24B, 24C. For example, controller 34 may control actuators (not shown) to control various operations of components of 3D printing system 10. Controller 34 may be a computing device, a semiconductor-based microprocessor, a central processing unit (CPU) , an application-specific integrated circuit (ASIC) and/or other hardware device. Although not shown, controller 34 can be connected to components of 3D printing system 10 via communication lines.
[0064] Controller 34 manipulates and transforms data, which can be represented as physical (electronic) quantities in the printer's registers and memories, to control the physical elements to create the 3D part. As such, the controller 34 is represented as being in communication with a data store 36. The data store 36 may include data pertaining to a 3D part to be printed by the 3D printing system 10. The data for selective delivery of the particles of building material 16, melting agent 26 or 26', core melting agent 28, color inkjet ink 30, etc. can be derived from a model of the 3D part to be formed. For example, the data may include the locations on each layer of building material particles 16 that the inkjet applicator(s) 24A, 24B, 24C must deposit the melting agent 26 or 26', the melting agent of core 28, color inkjet ink 30, and/or detailing agent 42. In one example, controller 34 may use data to control inkjet applicator 24A to selectively apply melting agent 26 or 26'. The data store 36 may also include machine-readable instructions (stored on a non-transient computer-readable medium) that must cause the controller 34 to control the amount of building material particles 16 that is supplied by the building material source. 14, the movement of the building area platform 12, the movement of the building material dispenser 18, the movement of the inkjet applicator(s) 24A, 24B, 24C, etc.
[0065] As shown in Figure 1, the printing system 10 may also include a radiation source 38, 38'. In some examples, the radiation source 38 may be in a fixed position with respect to the building material platform 12. In other examples, the radiation source 38' may be positioned to expose the building material particle layer 16 to the radiation immediately after the melting agent 26, 26' and/or the core melting agent 28 has been applied thereto. In the example shown in Figure 1, the radiation source 38' is attached to the side of the inkjet applicator(s) 24A, 24B, 24C, which allows for patterning and heating in a single pass.
[0066] The radiation source 38, 38' can emit electromagnetic radiation having wavelengths ranging from about 800 nm to about 1 mm. As an example, electromagnetic radiation can range from about 800 nm to about 2 μm. As another example, electromagnetic radiation can be blackbody radiation with a maximum intensity at a wavelength of about 1100 nm. The radiation source 38, 38' can be infrared (IR) or near-infrared light sources, such as IR or near IR curing lamps, or near IR or near IR light emitting diodes or lasers with the electromagnetic wavelengths of desirable IR or near IR.
[0067] The radiation source 38, 38' may be operatively connected to a lamp/laser driver, an input/output temperature controller, and temperature sensors, which are collectively shown as radiation system components 40. radiation system components 40 may operate together to control the radiation source 38, 38'. The temperature recipe (eg radiation exposure rate) can be submitted to the inlet/outlet temperature controller. During heating, the temperature sensors can detect the temperature of the building material particles 16, and the temperature measurements can be transmitted to the inlet/outlet temperature controller. For example, a thermometer associated with the heated area can provide temperature feedback. The inlet/outlet temperature controller can adjust the 38, 38' radiation source power setpoints based on any difference between the recipe and real-time measurements. These power set points are sent to the lamp/laser drivers, which transmit appropriate lamp/laser voltages to the radiation source 38, 38'. This is an example of radiation system components 40, and it should be understood that other radiation source control systems may be used. For example, controller 34 may be configured to control radiation source 38, 38'.
[0068] Referring now to Figure 2, an example of the 3D printing method 100 is represented. This example of the method uses the core melting agent 28 and the melting agent 26 or 26' (i.e. low-tone melting agent or primer melting agent). This method 100 can be used to form core layer(s) having mechanical integrity, and to form a white outer layer or a primer layer and an outer colored layer on the core layer(s).
[0069] An example of method 100 includes selectively applying core melting agent 18 to at least a portion of the building material (i.e., building material particles 16) (reference numeral 102); exporting the building material 16 to electromagnetic radiation, thereby melting the portion of the building material 16 in contact with the core melting agent 28 to form a core layer (reference numeral 104); applying a layer of building material 16 to the core layer (reference numeral 106); applying primer melting agent 26, 26' to at least a portion of the building material layer (reference numeral 108); and exposing the layer of building material to electromagnetic radiation, thereby melting the portion of the layer of building material in contact with the primer melting agent 26, 26' to form a layer (reference numeral 110). The layer that is formed with the primer melting agent 26, 26' may be a primer layer (on top of which another layer(s) is/are formed) or it may be an outer layer (or one of several layers forming a outer region) of the part that is formed.
[0070] Method 100 can be used to form a part 44, as shown in Figure 3, which includes multiple core layers 46, 46', 46” and an outer white layer 48. Core layers 46, 46', 46" are sequentially formed by selectively patterning respective building material layers with the core melting agent 28 and exposing each patterned layer to electromagnetic radiation. The outer white layer 48 is formed by applying a layer of building material to the outermost core layer. outer layer 46", patterning it with the melting agent 26, 26', and exposing it to electromagnetic radiation. The outer white layer 48 provides the part 44 with a white (or slightly tinted) outer surface. As such, the outer white layer 48 optically insulates the 46, 46', 46” black layer(s) it covers.
[0071] In the example part 44 shown in Figure 3, the white outer layer 48 does not completely surround the part 44, but rather can be formed on the outer surface(s) of the core layer 46” which will be visible. For example, in Figure 3, the surface 50 of the part 44 may not be visible when the part 44 is in use and thus it may not be desirable to form the white outer layer 48 on this surface 50.
[0072] It should be understood that method 100 may include further processing to form part 44 with a colored outer layer (not shown in Figure 3) on at least a portion of white outer layer 48, or to form another part 44' ( shown in Figure 4H) which has the core layer(s) 46 completely encapsulated by a primer layer (including portions of 48', 48”, 48”' primer layer, which are referred to herein respectively as primer layers 48, 48', 48") and an outer colored layer (including colored layer portions 52, 52', 52", which are referred to herein as colored layers 52, 52', 52"). Method 100' for forming part 44 ' will now be discussed with reference to Figures 4A to 4H. Throughout the method, a single inkjet applicator may be labeled with multiple reference numbers (24A, 24B and/or 24C), although it should be understood that the applicators may be separate applicators or a single applicator with multiple individual cartridges to dispense go the respective fluids.
[0073] In Figures 4A and 4B, a layer 54 of the building material particles 16 is applied to the building area platform 12. In Figure 4A, the building material supply 14 may supply the building material particles 16 in a position so that they are ready to be spread on the build area platform 12. In Figure 4B, the building material dispenser 18 can spread the building material particles 16 provided on the build area platform 12. The controller 34 can execute control building material supply instructions to control the building material supply 14 to properly position the building material particles 16, and may execute control spreader instructions to control the building material dispenser 18 to spread the building material particles 16 delivered over build area platform 12 to form layer 54 d and building material particles 16 therein. As shown in Figure 4B, a layer 54 of building material particles 16 was applied.
[0074] Layer 54 has a substantially uniform thickness across the build area platform 12. In one example, the thickness of layer 54 ranges from about 50 μm to about 300 μm, although thinner layers or thicker. For example, the thickness of layer 54 can vary from about 20 µm to about 500 µm, or from about 30 µm to about 300 µm. Layer thickness can be about 2x the particle diameter at a minimum for finer part definition.
[0075] To form part 44 shown in Figure 3, this layer 54 of building material would be patterned with core melting agent 28 (i.e., core melting agent 28 would be selectively dispensed into layer 54 in accordance with a pattern of a cross section for the core layer 46), and then exposed to electromagnetic radiation to form the core layer 46. As used herein, the cross section of the layer of the part to be formed refers to the cross section that is parallel to the contact surface of the build area platform 12. As an example, if the core layer 46 is shaped like a cube or cylinder, the core melting agent 28 will be deposited in a square or circular pattern (the from a top view), respectively, in at least a portion of the layer 54 of the building material particles 16.
[0076] In the example shown in Figure 4B, the layer 54 of building material particles 16 is a sacrificial layer that is used to enhance the color of the first layer (e.g. colored layer 52) of the part 44' being formed . As shown in Figure 4B, color inkjet ink 30 is selectively applied to at least portion 56 of layer 54. As such, particles of building material 16 in this portion 56 of layer 54 become colored. In this example, that sacrificial layer 54 is not fused (as no melting agent 26, 26' or core melting agent 28 is applied thereto). On the contrary, some of the colored building material particles 16 in the sacrificial layer 54 may be incorporated into molten building material particles of the part layer (e.g. colored layer 52) which is formed therein. In other words, part of the colored building material 16 in the portion 56 may become embedded in the surface of the part layer which is formed adjacent thereto. The unfused but embedded colored building material particles 16 can help maintain surface saturation (of the last formed colored layer 52) by providing a colored interface between the colored layer 52 and surrounding unfused building material particles 16.
[0077] While a sacrificial layer 54 is shown, it should be understood that several sacrificial layers 54 may be formed sequentially in contact with each other.
[0078] The color of the color inkjet ink 30 that is applied to the portion(s) 56 of the sacrificial layer 54 will depend on the desired color for the piece 44' or at least the portion of the colored layer 52 formed adjacent thereto. As examples, cyan ink, magenta ink, and yellow ink can be applied alone or in combination to obtain a variety of colors, and black ink (i.e., non-fusing black ink) can be printed with any of the other inks to change the color. or to lower the L* of the resulting color.
[0079] Although not shown in Figure 4B, the detailing agent 42 can be applied selectively to the portion 56 with the color inkjet ink 30. The detailing agent 42 can be used to maintain the temperature of the coloring material particles. construction 16 in contact with it below the melting point or softening point of the building material particles 16. Since the sacrificial layer 54 must not be melted, the detailing agent 42 can be applied to this layer 54 with color inkjet ink 30.
[0080] The color inkjet ink 30 will at least partially penetrate the sacrificial layer 54. Depending on the particle size of the dye in the color inkjet ink 30 and the size of the voids between the building material particles 16, the colored inkjet ink 30 can penetrate through the entire thickness of the sacrificial layer 54. This creates a surface onto which a subsequent layer 58 of building material particles 16 can be applied.
[0081] Layer 58 of building material particles 16 can be applied in the same manner as layer 54. Layer 58 is shown in Figure 4C. Layer 58 can be considered the first layer of building material because at least a portion of this layer 58 will be fused to form the first layer of the 3D part 44' (since the sacrificial layer 54 is not fused).
[0082] Prior to further processing, layer 58 of building material particles 16 may be exposed to heating. Heating may be performed to preheat the building material particles 16, and thus the heating temperature may be below the melting point or softening point of the building material particles 16. As such, the temperature selected will depend on of the building material particles 16 that are used. As examples, the preheat temperature can be from about 5°C to about 50°C below the melting point or softening point of the building material particles 16. In one example, the preheat temperature ranges from about 50°C to about 350°C. In another example, the preheat temperature ranges from about 150°C to about 170°C.
[0083] Preheating layer 58 of building material particles 16 may be accomplished using any suitable heat source that exposes all building material particles 16 on the building material surface 12 to heat. Examples of the heat source include a thermal heat source (e.g., a particle heater (not shown) 16) or electromagnetic radiation source 38, 38'.
[0084] After the layer 58 is formed, and in some cases is preheated, the melting agent 26, 26' or the core melting agent 28 and the color inkjet ink 30 are selectively applied thereto. portion(s) of building material particles 16 in layer 58. In Figure 4C, melting agent 26, 26' and color inkjet ink 30 are shown being applied to portion 60 of layer 58. fusion 26, 26' or core fusing agent 28 and color inkjet ink 30 are selectively applied in a cross-sectional pattern to the color layer 52 that is to be formed (shown in Figure 4D).
[0085] In the example shown in Figure 4C, portion 60 is adjacent to portion 56 of layer 54 to which color inkjet ink 30 has been applied.
[0086] When the desired color for the part 44' or a particular colored layer 52 of the part 44' is the color of the color inkjet ink 30, the melting agent 26, 26' is applied with the inkjet ink. color ink 30. Once the melting agent 26, 26' is clear or lightly tinted, the color of the color inkjet ink 30 will be the color of the resulting color layer 52 as the color ink jet dyes colored ink 30 become incorporated into the material particles of colored layer 52. Fusing agent 26, 26' may be particularly suitable for obtaining lighter colors or white. When the desired color for the colored layer 52 is a darker color or black, the core melting agent 28 can be applied with the colored inkjet ink 30.
[0087] After the melting agent 26, 26' or the core melting agent 28 and the color inkjet ink 30 are selectively applied to the specific portion(s) 60 of layer 58, the entire layer 58 of the construction 16 is exposed to electromagnetic radiation (shown as EMR Exposure between Figures 4C and 4D).
[0088] Electromagnetic radiation is emitted from the radiation source 38, 38'. The period of time during which electromagnetic radiation is applied, or the time of energy exposure, may be dependent on, for example, one or more of: characteristics of the radiation source 38, 38'; characteristics of building material particles 16; and/or characteristics of the melting agent 26, 26' or the core melting agent 28.
[0089] Melting agent 26, 26' or core melting agent 28 increases radiation absorption, converts absorbed radiation into thermal energy, and promotes transfer of thermal heat to building material particles 16 in contact with the same. In one example, the melting agent 26, 26' or the core melting agent 28 sufficiently raises the temperature of the building material particles 16 in layer 58 above the melting or softening point of the particles 16, allowing melting ( e.g. sintering, bonding, curing, etc.) of building material particles. Exposure to electromagnetic radiation forms the colored layer 52, as shown in Figure 4D.
[0090] Furthermore, it should be understood that portions of the building material 16 that do not have the melting agent 26, 26' or the core melting agent 28 applied thereto do not absorb sufficient energy to melt. However, the thermal energy generated can propagate to the surrounding building material 16, which does not have the melting agent 26, 26' or the core melting agent 28 applied thereto. Thermal energy propagation can be inhibited by melting non-standard building material particles 16 in layer 58, for example, when detailing agent 42 is applied to building material particles 16 in layer 58 that are not exposed to the agent. 26, 26' or the core melting agent 28. In addition, the propagation of thermal energy can be inhibited by melting the building material particles 16 into the layer 54 when the detailing agent 42 is applied with the paint. colored inkjet 30 in layer 54. However, as mentioned above, part of the colored building material particles 16 in layer 54 may become embedded in the adjacent surface of the fused building material particles of colored layer 52.
[0091] While a single colored layer 52 is shown, it should be understood that several colored layers 52 can be formed sequentially in contact with each other, so that a colored region (thicker than a voxel) is built around the core layer(s) 46 at the end portion 44'. The outermost colored layer 52 may form a shell one voxel in depth, and the other colored layers may create the thicker region of color. Fluid levels of melting agent 26, 26' or core melting agent 28 and color inkjet ink 30 may be higher in the outermost colored layer 52 as compared to other colored layers positioned closer to the layer. (s) of core 46, in order to increase the color saturation on the outside of the formed part 44'.
[0092] Figure 4D also illustrates yet another layer 62 of the building material particles 16, this time the layer 62 being applied to the colored layer 52 and any unfused building material particles 16 of layer 58. The layer 62 may be applied in the same way as layers 54, 58.
[0093] Prior to further processing, layer 62 of building material particles 16 may be exposed to preheat in the manner previously described.
[0094] After layer 62 is formed, and in some cases is preheated, the melting agent 26, 26' is selectively applied to the portion(s) 64 of the building material particles 16 in layer 62. s) 64 of layer 62 will form primer layer 48', which is white, clear, or lightly tinted from melting agent 26, 26'. This primer layer 48' is positioned between the colored layer 52 and subsequently formed black core layer(s) 46 in the piece 44' (see Figure 4H). This 48' primer coat may be referred to as the starter coat or first coat of primer. Primer layer 48' optically isolates at least a portion of black core layer(s) 46.
[0095] In the example shown in Figure 4D, the portion 64 to which the fusing agent 26, 26' is selectively applied adjacent to part (but not all) of the already formed colored layer 52. Selective application of the fusing agent 26, 26 ' in this way can be realized when it is desirable to form colored layer(s) 52' (shown in Figure 4E) along the sides of the piece 44' being formed. To form the colored layer(s) 52' along the sides of the part 44', the melting agent 26, 26' or the core melting agent 28 and the colored inkjet ink 30 are selectively applied to another portion. (s) 66 of building material particles 16 in layer 62. As an example, portion(s) 66 may define the perimeter of that particular layer of the part 44' being formed, and may be outside a perimeter or boundary. edge E (i.e., the outermost parts where the melting agent 26, 26' alone is selectively deposited on any layer of building material) of portion 64.
[0096] When it is desirable to form the colored layer 52' (shown in Figure 4E) along the sides of the part 44' being formed, it may also be desirable to selectively deposit the colored inkjet ink 30 (with or without the detailing agent 42) in the portion(s) 68 of the non-standard building material particles 16 that are adjacent to or surround the portion(s) 66 (which when melted will form the colored layer 52' along the sides of the piece 44') . The colored building material particles 16 in the portion(s) 68 may become embedded in molten building material particles of the colored layer 52'. This non-melted but embedded colored building material 16 can help maintain surface saturation (of the colored layer 52') by providing a colored interface between the colored layer 52' and surrounding unfused building material particles 16.
[0097] If it is not desirable to color the sides of the part 44', the portion 64 to which the melting agent 26, 26' is selectively applied may be adjacent to part or all of the already formed colored layer 52, but the melting agent 26, 26' is selectively applied. melt 26, 26' or core melting agent 28 and color inkjet ink 30 will not be selectively applied to the portion(s) 66 of the building material particles 16 in layer 62.
[0098] After the fusing agent 26, 26' is applied to the portion(s) 64 and in some cases the fusing agent 26, 26' or the core fusing agent 28 and the color inkjet ink 30 are applied selectively to the portion(s) 66, the entire layer 62 of the building material particles 16 is exposed to electromagnetic radiation (shown as EMR Exposure between Figures 4D and 4E) in the manner previously described.
[0099] In this example, the melting agent 26, 26' increases the absorption of radiation in the portion 64, converts the absorbed radiation into thermal energy, and promotes the transfer of thermal heat to the building material particles 16 in contact with the same. In one example, the melting agent 26, 26' sufficiently raises the temperature of the building material particles 16 in the portion 64 above the melting or softening point of the particles 16, allowing melting (e.g., sintering, binding, curing , etc.) of building material particles occur. Exposure to electromagnetic radiation forms the 48' primer layer, as shown in Figure 4E.
[00100] If fusing agent 26, 26' or core fusing agent 28 and color inkjet ink 30 are applied selectively to portion(s) 66, EMR exposure will form color layer(s) 52 ' on the outer edge(s). In these portions 66, the melting agent 26, 26' or the core melting agent 28 increases the absorption of radiation, converts the absorbed radiation into thermal energy, and promotes the transfer of thermal heat to the contacting building material particles. with the same, causing them to merge. This exposure to electromagnetic radiation forms the colored layer(s) 52', as shown in Figure 4E.
[00101] The width of the colored layer(s) 52' may be large enough to form the region of color in this portion of the part 44'. The fluid levels of the fusing agent 26, 26' or the core fusing agent 28 and the color inkjet ink 30 may be higher at the outermost edge of the color layer(s) (52) compared to the innermost edge(s) of the colored layer(s) 52', so as to increase the color saturation on the outside of the formed part 44'.
[00102] Figure 4E also illustrates yet another layer 70 of the building material particles 16, this time being layer 70 being applied to the primer layer 48', the colored layer(s) (52) and any material particles unfused building blocks 16 of layer 62. Layer 70 can be applied in the same manner as layers 54, 58, 62.
[00103] Prior to further processing, the layer 70 of the building material particles 16 may be exposed to preheat in the manner previously described.
[00104] After layer 70 is formed, and in some cases is preheated, the core melting agent 28 is selectively applied to the portion(s) 72 of the building material particles 16 in layer 70. The portion( ions) 72 of layer 70 will form the core layer 46 (Figure 4F), which may be black from the core melting agent 28. While a single core layer 46 is shown, it should be understood that multiple core layers 46 may be sequentially formed in contact with each other, so that a core region (or part core) is constructed, which constitutes the majority of part 44'. Multiple layers of core 46 can improve the mechanical properties of part 44'.
[00105] In the example shown in Figure 4E, the portion 72 to which the core melting agent 28 is applied is selectively adjacent to part (but not all) of the already formed primer layer 48'. Selective application of the core melting agent 28 in this manner can be accomplished when it is desirable to form colored layer(s) 52' (shown in Figure 4F) along the sides of the piece 44' being formed. Since the core layer 46 being formed may be black, it may also be desirable to form the primer layer 48" between the core layer 46 and the adjacent colored layer(s) 52'.
[00106] To form the primer layer 48" along the perimeter of the core layer 46, the melting agent 26, 26' is selectively applied to another (or second) portion(s) 74 of the building material particles 16 on layer 70 that are immediately adjacent to the perimeter or edge boundary E' (i.e., the outermost parts where the core melting agent 28 is selectively deposited on any building material layer) of portion 72. The perimeter/boundary edge E' is thus defined by the core melting agent 28. To form the colored layer(s) 52' along/adjacent to the perimeter of the primer layer 48”, the melting agent 26, 26' or the core melt 28 and color inkjet ink 30 are selectively applied to yet another (or third) portion(s) 76 of the building material particles 16 in layer 70 that is immediately adjacent to the perimeter or edge boundary E of the portion 74 (which is defined by primer fusion agent 26, 26' ).
[00107] When it is desirable to form the colored layer(s) 52' (shown in Figure 4F) along the sides of the part 44' being formed, it may also be desirable to selectively deposit the colored inkjet ink 30 (with or without the detailing agent 42) in the portion(s) 78 of the non-standard building material particles 16 that are adjacent to or surround the portion(s) 76 (which, when melted, will form the colored layer 52' along the sides of part 44'). The colored building material particles 16 in the portion(s) 78 may become embedded in molten building material particles of the colored layer 52'. The non-fused, but embedded, colored building material particles 16 can help maintain surface saturation (of the colored layer 52') by providing a colored interface between the colored layer(s) 52' and unfused building material particles. surrounding fused 16.
[00108] If it is not desirable to color the sides of the part 44' (e.g. if part of the core layer 46 is exposed/visible, the portion 72 to which the melting agent 28 is selectively applied may be adjacent for some or all the already formed layers 48', 52', but the melting agent 26, 26' will not be selectively applied to the portion(s) 74 and the melting agent 26, 26' or the core melting agent 28 and the ink from color inkjet 30 will not be selectively applied to the portion(s) 76 of the building material particles 16 in layer 70.
[00109] After layer 70 is patterned in a desirable manner with at least the core melting agent 28, the entire layer 70 of the building material particles 16 is exposed to electromagnetic radiation (shown as EMR Exposure between Figures 4E and 4F) in the manner previously described.
[00110] In this example, the melting agent 28 increases the absorption of radiation in the portion 72, converts the absorbed radiation into thermal energy, and promotes the transfer of thermal heat to the building material particles 16 in contact therewith. In one example, the melting agent 28 sufficiently raises the temperature of the building material particles 16 in the portion 72 above the melting or softening point of the particles 16, allowing melting (e.g., sintering, binding, curing, etc.) of building material particles occur. Exposure to electromagnetic radiation forms the core layer 46, as shown in Figure 4F.
[00111] If the fusing agent 26, 26' is selectively applied to the portion(s) 74, and the fusing agent 26, 26' or the core fusing agent 28 and the color inkjet ink 30 are applied selectively at portion(s) 76, EMR exposure also forms 48” primer layer(s) and 52' colored layer(s) on the outer edge(s) of core layer 46. In that portion(s) 74, 76 , the agent(s) 26, 26' and/or 28 increases the absorption of radiation in the portion(s) 74, 76, converts the absorbed radiation into thermal energy, and promotes the transfer of thermal heat to the building material particles 16 in contact with it, causing them to fuse. This exposure to electromagnetic radiation forms 48' primer layer(s) and 52' colored layer(s), as shown in Figure 4F.
[00112] The width of the 48” primer layer(s) may be large enough to optically isolate the black core layer 46. The width of the 52' colored layer(s) may be large enough to form the color region in that portion of the piece 44'. Fluid levels of fusing agent 26, 26' or core fusing agent 28 and color inkjet ink 30 may be higher at the outermost edge of the color layer(s) 52' compared to the edge innermost(s) of the colored layer(s) 52', so as to increase the color saturation on the outside of the formed part 44'.
[00113] Figure 4F also illustrates yet another layer 80 of the building material particles 16, this time layer 80 being applied to the core layer 46, the primer layer(s) 48”, the colored layer(s) 52 ', and any unfused building material particles 16 of layer 70. Layer 80 may be applied in the same manner as layers 54, 58, 62, 70.
[00114] Prior to further processing, the layer 80 of the building material particles 16 may be exposed to preheat in the manner previously described.
[00115] After layer 80 is formed, and in some cases is preheated, the melting agent 26, 26' is selectively applied to the portion(s) 82 of the building material particles 16 in layer 80. 82 of layer 82 will form another primer layer 48”', which is white or lightly tinted from the melting agent 26, 26'. This 48”' primer layer is positioned between the 46 black core layer(s) and subsequently formed colored layer(s) 52" on the 44' piece (see Figure 4H). As such, the 48" primer layer optically isolates the black core layer(s) 46 at another end of the formed piece 44'.
[00116] In the example shown in Figure 4F, the portion 82 to which the fusing agent 26, 26' is selectively applied is adjacent to the already formed core layer(s) 46 and primer layer(s) 48”. Selectively applying the melting agent 26, 26' in this manner can be accomplished when it is desirable to form colored layer(s) 52' (shown in Figure 4G) along the sides of the piece 44' being formed. To form the colored layer(s) 52' along the sides of the part 44', the melting agent 26, 26' or the core melting agent 28 and the colored inkjet ink 30 are selectively applied to the portion ( 84 of the building material particles 16 in layer 82. As an example, the portion(s) 84 may define the perimeter of that particular layer of the part 44' being formed, and may be outside an edge boundary E of the portion 82.
[00117] When it is desirable to form the colored layer 52' (shown in Figure 4G) along the sides of the part 44' being formed, it may also be desirable to selectively deposit the colored inkjet ink 30 (with or without the detailing agent 42) in the portion(s) 86 of the non-standard building material particles 16 that are adjacent to or surround the portion(s) 84 (which, when melted, will form the colored layer 52' along the sides of the piece 44 '). The colored building material particles 16 in the portion(s) 86 may become embedded in fused building material particles of the colored layer 52'. The unfused, but embedded, colored building material particles 16 can help maintain surface saturation (of the colored layer 52') by providing a colored interface between the colored layer 52' and the unfused building material particles 16. surrounding.
[00118] If it is not desirable to color the sides of the part 44', the portion 82 to which the melting agent 26, 26' is selectively applied may be adjacent to some or all of the already formed colored layer 52', but the melting agent 26, 26' is selectively applied. 26, 26' or core fusing agent 28 and color inkjet ink 30 will not be selectively applied to the portion(s) 84 of the building material particles 16 in layer 80.
[00119] After the fusing agent 26, 26' is applied to the portion(s) 82, and in some cases, the fusing agent 26, 26' or the core fusing agent 28 and the color inkjet ink 30 are applied selectively to the portion(s) 84, the entire layer 80 of the building material particles 16 is exposed to electromagnetic radiation (shown as EMR Exposure between Figures 4F and 4G) in the manner previously described.
[00120] In this example, melting agent 26, 26' increases absorption of radiation in portion 82, converts absorbed radiation into thermal energy, and promotes transfer of thermal heat to building material particles 16 in contact therewith. . In one example, the melting agent 26, 26' sufficiently raises the temperature of the building material particles 16 in the portion 82 above the melting or softening point of the particles 16, allowing melting (e.g., sintering, binding, curing , etc.) of building material particles occur. Exposure to electromagnetic radiation forms the 48”' primer layer, as shown in Figure 4G.
[00121] If fusing agent 26, 26' or core fusing agent 28 and color inkjet ink 30 are selectively applied to portion(s) 84, EMR exposure will form color layer(s) 52 ' on the outer edge(s) of the 48”' primer coat. In these portions 84, the melting agent 26, 26' or the core melting agent 28 increases the absorption of radiation, converts the absorbed radiation into thermal energy, and promotes the transfer of thermal heat to the building material particles 16 in contact with the same, making them merge. This exposure to electromagnetic radiation forms the colored layer(s) 52', as shown in Figure 4G.
[00122] The width of the colored layer(s) 52' may be large enough to form the region of color in this portion of the part 44'. The fluid levels of the fusing agent 26, 26' or the core fusing agent 28 and the color inkjet ink 30 may be higher at the outermost edge of the color layer(s) (52) compared to the innermost edge(s) of the colored layer(s) 52', so as to increase the color saturation on the outside of the formed part 44'.
[00123] Figure 4G also illustrates yet another layer 88 of the building material particles 16, this time layer 88 being applied to the primer layer(s) 48”' and the colored layer(s) 52" adjacent thereto, and to any unfused building material particles 16 of layer 80. Layer 88 may be applied in the same manner as layers 54, 58, 62, 70, 80.
[00124] Prior to further processing, the layer 88 of the building material particles 16 may be exposed to preheat in the manner previously described.
[00125] After the layer 88 is formed, and in some cases is preheated, the melting agent 26, 26' or the core melting agent 28 and the color inkjet ink 30 are selectively applied to the same portion (s) of building material particles 16 in layer 88. In Figure 4G, melting agent 26, 26' and color inkjet ink 30 are shown being applied to portion 90 of layer 88. Melting agent 26, 26' or core melting agent 28 and color inkjet ink 30 are selectively applied in a pattern of a cross section to the color layer 52" that is to be formed (shown in Figure 4H).
[00126] In the example shown in Figure 4G, portion 90 is adjacent to primer layer 48”' and colored layer(s) 52' adjacent to primer layer 48”'.
[00127] When the desired color for part 44' or a particular colored layer 52” of part 44' is the color of the color inkjet ink 30, the melting agent 26, 26' is applied with the inkjet ink. of color ink 30. Since the melting agent 26, 26' is light or lightly colored, the color of the color inkjet ink 30 will be the color of the resulting color layer 52", as the dyes in the color ink color inkjet 30 are incorporated into all fused building material particles of the color layer 52”. The melting agent 26, 26' may be particularly suitable for obtaining lighter colors or white. When the desired color for the color layer 52" is a darker color or black, the core melting agent 28 can be applied with the color inkjet ink 30.
[00128] It may also be desirable to selectively deposit the color inkjet ink 30 (with or without the detailing agent 42) on the portion(s) 92 of the non-standard building material particles 16 that are adjacent to or surround the portion(s) ions) 90 (which when melted will form the colored layer 52” along the top surface of the piece 44'). The colored building material particles 16 in the portion(s) 92 may become embedded in fused building material particles along the sides or edges of the colored layer 52". The unfused, but embedded, colored building material particles 16 can help maintain surface saturation (of the colored layer 52”) by providing a colored interface between the colored layer 52" and surrounding unfused building material particles 16. .
[00129] After the melting agent 26, 26' or the core melting agent 28 and the color inkjet ink 30 are selectively applied to the specific portion(s) 90 of layer 88, the entire layer 88 of the construction 16 is exposed to electromagnetic radiation (shown as EMR Exposure between Figures 4G and 4H). Electromagnetic radiation is emitted from the radiation source 38, 38' in the manner described above.
[00130] Melting agent 26, 26' or core melting agent 28 increases radiation absorption, converts absorbed radiation into thermal energy, and promotes transfer of thermal heat to building material particles 16 in contact with the same. In one example, melting agent 26, 26' or core melting agent 28 sufficiently raises the temperature of building material particles 16 in portion 90 of layer 88 above the melting or softening point of particles 16, allowing the melting (eg sintering, binding, curing, etc.) of building material particles (in contact with agent 26, 26' or 28). Exposure to electromagnetic radiation forms the colored layer 52”, as shown in Figure 4H, having inkjet ink dyes 30 incorporated therein.
[00131] While a single 52” colored layer is shown, it should be understood that multiple 52” colored layers can be formed sequentially in contact with each other, so that a region of color (thicker than a voxel) is constructed in around the core layer(s) 46 in the end piece 44'. The outermost colored layer 52” may form a shell one voxel in depth, and the other colored layers may create the thickest color region. Fluid levels of the fusing agent 26, 26' or core fusing agent 28 and the color inkjet ink 30 may be greater in the outermost color layer 52", compared to other color layers positioned closer to the color layer(s). core 46, in order to increase the color saturation on the outside of the formed part 44'.
[00132] Although not shown, color inkjet ink 30 can be selectively applied to color layer 52”. Color inkjet ink 30 applied to color layer 52" can help maintain saturation on the surface of color layer 52" by coloring building material particles on the surface, whether these particles are fused or not fused and incorporated into the particles. fused.
[00133] The color of the color inkjet ink 30 that is applied to the color layer 52" will depend on the desired color for the part 44' or at least the color layer 52" to which the ink 30 is applied. As examples, Cyan ink, magenta ink, and yellow ink can be applied alone or in combination to achieve a variety of colors, and black ink (i.e., non-fusing black ink) can be printed with any of the other inks to change color or to lower the L* of the resulting color.
[00134] Also, while not shown, it is to be understood that the detailing agent 42 can be selectively applied to the color layer 52" with the color inkjet ink 30.
[00135] It should further be understood that the method 100' may be modified so that the sacrificial layer 54 (with inkjet ink 30 therein) and the outer colored layers 52, 52', 52" are not formed. In this modified form of the 100' method, the 48' primer layer would be formed first. In the resulting part, all primer coats 48', 48”, 48"' would be exposed/visible, and thus would form the exterior of the part. In this example, primer coats 48', 48”, 48"' would form a layer white outer layer that encapsulates the core layer(s) 46. When method 100' is modified in this way, the part that is formed is either white or lightly dyed (depending on the color of the melting agent 26, 26').
[00136] Referring now to Figure 5, another example of the 3D printing method 200 is represented. This example method utilizes the 26' melting agent, which includes the CTO nanoparticles, the zwitterionic stabilizer, and the aqueous carrier. This method 200 can be used to form a 44” white or lightly colored part (shown in Figure 6C).
[00137] An example of method 200 includes applying polymeric building material (i.e. building material particles 16) (reference numeral 202); selectively applying the melting agent 26' to at least a portion of the polymeric building material, wherein, as noted above, the melting agent 26' includes the CTO nanoparticles, the zwitterionic stabilizer and the aqueous vehicle (reference number 204) ; and exposing the polymeric building material to electromagnetic radiation, thereby melting the portion of the polymeric building material in contact with the melting agent 26' to a layer (reference numeral 206). Figures 6A to 6D illustrate examples of method 200.
[00138] In Figure 6A, a layer 94 of the building material particles 16 is applied to the building area platform 12. As previously described, the building material supply 14 can deliver the building material particles 16 at a position so that they are ready to be spread over the build area platform 12, and the building material dispenser 18 can spread the supplied building material particles 16 on the build area platform 12. The controller 34 can execute instructions of control building material supply to control the building material supply 14 to properly position the building material particles 16, and can execute control spreader instructions to control the building material dispenser 18 to spread the material particles 16 on the build area platform 12 to form the pair layer 94 building material chips 16 therein.
[00139] Layer 94 of building material particles 16 may be exposed to preheat in the manner described herein.
[00140] After layer 94 is applied, and in some cases is preheated, the melting agent 26' is selectively applied to the portion(s) 96 of the building material particles 16 in layer 94. The portion(s) 96 of layer 62 will form the first layer 98 of the 44” (Figure 6C) or 44”' (Figure 6D) 3D piece to be formed. As such, the melting agent 26' is selectively dispensed into layer 94 in a cross-sectional pattern for layer 98.
[00141] After the melting agent 26' is applied to the portion(s) 96, the entire layer 94 of the building material particles 16 is exposed to electromagnetic radiation (shown as EMR Exposure between Figures 6A and 6B) in the manner described here.
[00142] In this example, the melting agent 26' increases the absorption of radiation in the portion(s) 96, converts the absorbed radiation into thermal energy, and promotes the transfer of thermal heat to the building material particles 16 in contact with the same. In one example, the melting agent 26' sufficiently raises the temperature of the building material particles 16 in the portion 96 above the melting or softening point of the particles 16, allowing melting (e.g., sintering, binding, curing, etc.). .) of building material particles 16 occur. Exposure to electromagnetic radiation forms layer 98, as shown in Figure 6B.
[00143] It should be understood that portions of the building material 16 that do not have the melting agent 26' applied thereto do not absorb sufficient energy to melt.
[00144] After layer 98 is formed, additional layer(s) (e.g. 98', 98", 98'" shown in Figure 6C) can be formed on it to create an example of 3D part 44” (shown in Figure 6C). For example, to form the other layer 98', additional polymeric building material (i.e., particles 16) can be applied to layer 98. The melting agent 26' is then selectively applied to at least a portion of the particles of building material. additional construction 16, according to a pattern of a cross section for the layer (eg 98') being formed. After the melting agent 26' is applied, the entire layer of additional polymeric building material (i.e., particles 16) is exposed to electromagnetic radiation in the manner described above. Application of additional polymeric building material particles 16, selective application of melting agent 26', and exposure to electromagnetic radiation may be repeated a predetermined number of cycles to form part 44".
[00145] In the example shown in Figures 6A and 6B, color can be applied to the entire part 44" by applying the color inkjet ink 30 with the melting agent 26' to each of the portions of the respective layers of bonding material. construction that form layers 98, 98', 98", 98"'.
[00146] Method 200 may end in forming part 44" or color may be imparted to the top surface of part 44". This is shown in Figures 6C and 6D.
[00147] To impart color and form part 44"' (shown in Figure 6D), a final layer 112 of polymeric building material particles 16 is applied to part 44". As shown in Figure 6C, this layer 112 is applied to the outermost layer 98"' of part 44". Prior to further processing, layer 112 may be exposed to preheat in the manner previously described.
[00148] After the layer 112 is formed, and in some cases is preheated, the melting agent 26' and the color inkjet ink 30 are selectively applied to the same portion(s) 114 of the material particles of construction 16 on layer 112. Fusing agent 26' and color inkjet ink 30 are selectively applied in a cross-sectional pattern to the color layer 52" that is to be formed (shown in Figure 6D). The color of the 30 color inkjet ink that is applied will depend on the desired color for the 44"' part.
[00149] After the melting agent 26' and the color inkjet ink 30 are applied, the entire layer 112 of the polymeric building material (i.e., particles 16) is exposed to electromagnetic radiation in the manner described above. The melting agent 26' increases the absorption of radiation, converts the absorbed radiation into thermal energy, and promotes the transfer of thermal heat to the building material particles 16 in contact therewith. In one example, melting agent 26' sufficiently raises the temperature of building material particles 16 in portion 114 of layer 112 above the melting or softening point of particles 16, allowing melting (e.g., sintering, agglutination, curing, etc.) of building material particles (in contact with agent 26'). Exposure to electromagnetic radiation forms the colored layer 52”, as shown in Figure 6D, having inkjet ink dyes 30 embedded therein.
[00150] While a single 52" colored layer is shown, it should be understood that multiple 52" colored layers may be formed sequentially in contact with each other, so that a region of color (thicker than a voxel) is accumulated in the layers 98, 98', 98”, 98"' in the final piece 44”'. The outermost colored layer 52" can form a shell one voxel in depth, and the other colored layers can create the thickest color region. The fluid levels of the fusing agent 26' and the color inkjet ink 30 may be greater on the outermost outer layer 52”, compared to other colored layers positioned closer to the 98” layer, in order to increase the color saturation on the outside of the formed part 44”'.
[00151] Although not shown, color inkjet ink 30 can be selectively applied to color layer 52”. Color inkjet ink 30 applied to color layer 52" can help maintain saturation on the surface of color layer 52" by coloring building material particles on the surface, whether these particles are fused or not fused and incorporated into the particles. fused.
[00152] It should be understood that method 200 may also be modified similarly to method 100' in order to form colored layers (e.g. 52 and 52') so that part 44'' is completely encapsulated by layers colored.
[00153] In any of the examples disclosed herein, when the 3D part 44, 44', 44”, 44"' is complete, it can be removed from the building material platform 12, and any unfused building material 16 can be removed. be removed from 3D part 44, 44', 44”, 44"'.
[00154] It should be understood that the ranges provided here include the declared range and any value or subrange within the declared range. For example, a range of about 2% by weight to about 35% by weight should be interpreted to include not only the explicitly recited limits of about 2% by weight to about 35% by weight, but also to include individual values, such as 3.35% by weight, 5.5% by weight, 17.75% by weight, 28.85% by weight, etc., and sub-ranges, such as about 3.35% by weight to about from 16.5% by weight, from about 2.5% by weight to about 27.7% by weight, and the like. Also, when "about" is used to describe a value, this means covering small variations (up to +/- 10%) from the declared value.
[00155] Reference throughout the specification to "1 example", "another example", "an example", and so on, means that a particular element (e.g. feature, structure and/or characteristic) described in connection with the example is included in at least one example described herein and may or may not be present in other examples. Furthermore, it is to be understood that the elements described for any given example may be combined in any suitable manner in the various examples, unless the context clearly dictates otherwise.
[00156] In describing and claiming the examples disclosed herein, the singular forms "a", "an", and "the" include the plural referents unless the context clearly indicates otherwise.
[00157] While several examples have been described in detail, it is to be understood that the disclosed examples may be modified. Therefore, the foregoing description should be considered non-limiting.

权利要求:
Claims (11)
[0001]
1. A method for adding color to a part during three-dimensional (3D) printing, the method comprising: selectively applying a core melting agent (18, 28) to at least a portion of a building material (16, 102); exposing the building material (16) to electromagnetic radiation, thereby melting the portion of the building material (16) in contact with the core melting agent (18, 28) to form a core layer (46, 104); applying a layer of building material (16) to the core layer (106); applying a primer melting agent (26, 26') to at least a portion of the building material layer (108), exposing the building material layer to electromagnetic radiation having wavelengths ranging between 800 nm and 4000 nm, thereby melting the portion of the layer of building material (108) in contact with the primer melting agent to form a layer (110); wherein the method is characterized in that the primer melting agent (26, 26') includes: cesium tungsten oxide nanoparticles; a zwitterionic stabilizer, wherein the zwitterionic stabilizer is selected from the group consisting of a C2 to C8 betaine, a C2 to C8 aminocarboxylic acid having a solubility of at least 10 g in 100 g of water, taurine and combinations thereof; and an aqueous vehicle, wherein the aqueous vehicle includes water, a co-solvent and a surfactant; and wherein the method further comprises: applying another layer (58) of the building material to the layer (110); applying a colored inkjet paint (30) and i) the core melting agent (18, 28) or ii) the primer melting agent (26, 26') to at least a portion of the other layer of primer material. construction (58); and exposing the other layer of building material (58) to electromagnetic radiation, thereby melting the portion of the other layer of building material (58) in contact with i) the core melting agent (18, 28) or ii) the primer melting agent (26, 26') to form a colored layer (52) having an inkjet ink dye incorporated therein.
[0002]
2. Method, according to claim 1, characterized in that it further comprises applying the colored inkjet ink (30) to the colored layer (52).
[0003]
3. Method according to claim 2, characterized in that it further comprises applying a detailing agent (42) with the colored inkjet ink (30).
[0004]
4. Method according to claim 1, characterized in that before the formation of the core layer (46, 106), the layer (108), and the colored layer (52), the method further comprises: applying the colored inkjet ink (30) on a layer of sacrificial building material (54); applying a first layer of building material (108) to the sacrificial building material layer (54); applying the color inkjet paint (30) and i) the core melting agent (18, 28) or ii) the primer melting agent (26, 26') to at least a portion of the first layer of primer material. construction (58); exposing the first layer of building material (58) to electromagnetic radiation, thereby melting the portion of the first layer of building material (58) in contact with i) the core melting agent (18, 28) or ii) the primer melting agent (26, 26') to form a first colored layer (52) having an inkjet ink dye incorporated therein; applying a second layer of building material to the first layer of building material (58); applying the primer melting agent (26,26') to at least a portion of the second layer of building material; and exposing the second layer of building material to electromagnetic radiation, thereby melting the portion of the second layer of building material in contact with the primer melting agent (26, 26') to form an initial layer; and wherein the core layer is formed on the initial layer.
[0005]
5. Method according to claim 1, characterized in that prior to exposing the building material (16) to electromagnetic radiation to form the core layer (46, 104), the method further comprises applying the melting agent of primer (26, 26') on a second portion of the building material (16) adjacent to a perimeter defined by the core melting agent (18, 28), and wherein exposing the building material (16) to radiation electromagnetic radiation to form the core layer (46, 104) also forms a layer portion (48).
[0006]
6. Method according to claim 5, characterized in that it further comprises applying a colored inkjet ink (30) and i) the core melting agent (18, 28) or ii) the core melting agent (18, 28) primer (26, 26') in a third portion adjacent to a perimeter defined by the primer melting agent (26, 26'), and wherein exposing the building material (16) to electromagnetic radiation to form the core layer (46, 104) also forms a colored layer portion (52) adjacent a perimeter of the layer portion (48).
[0007]
7. Method according to claim 1, characterized in that the core melting agent (18, 28) is a black melting agent, and wherein prior to the formation of the layer, the method further comprises building a core part forming several layers of core with the black fusing agent.
[0008]
8. A 3D printing method, comprising: applying a polymeric building material (16); selectively applying a melting agent (26, 26') to at least a portion of the polymeric building material (16), exposing the polymeric building material (16) to electromagnetic radiation, thereby melting the portion of the polymeric building material (16) (16) contacting the melting agent (26, 26') to form a layer; wherein the method is characterized in that the melting agent (26, 26') includes: cesium-tungsten oxide nanoparticles; a zwitterionic stabilizer, wherein the zwitterionic stabilizer is selected from the group consisting of a C2 to C8 betaine, a C2 to C8 aminocarboxylic acid having a solubility of at least 10 g in 100 g of water, taurine and combinations thereof; and an aqueous vehicle, the aqueous vehicle includes water and a surfactant.
[0009]
9. 3D printing method, according to claim 8, characterized in that it further comprises: applying additional polymeric construction material (16) in the layer; applying the melting agent (26, 26') to at least a portion of the additional polymeric building material (16); and exposing the additional polymeric building material (16) to electromagnetic radiation, thereby melting the at least a portion of the additional polymeric building material (16) to form another layer.
[0010]
10. 3D printing method, according to claim 9, characterized in that it further comprises repeating the application of additional polymeric construction material (16), the application of the melting agent (26, 26'), and the exposure a predetermined number of cycles to form a part.
[0011]
11. 3D printing method, according to claim 10, characterized in that it further comprises: applying a final layer of construction material (16) on the part; applying a colored inkjet ink (30) and the melting agent (26, 26') to at least a portion of the final layer; exposing the final layer to electromagnetic radiation, thereby melting the portion of the final layer in contact with the melting agent (26, 26') to form a colored layer having an inkjet ink dye incorporated therein; and applying the color inkjet ink (30) to the color layer.

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引用文献:

---

公开号 | 申请日 | 公开日 | 申请人 | 专利标题

---

---

US5204055A|1989-12-08|1993-04-20|Massachusetts Institute Of Technology|Three-dimensional printing techniques|

---

US7708974B2|2002-12-10|2010-05-04|Ppg Industries Ohio, Inc.|Tungsten comprising nanomaterials and related nanotechnology|

---

US5973026A|1998-02-02|1999-10-26|Xerox Corporation|Ink jet inks|

---

US6832735B2|2002-01-03|2004-12-21|Nanoproducts Corporation|Post-processed nanoscale powders and method for such post-processing|

---

DE102004020452A1|2004-04-27|2005-12-01|Degussa Ag|Method for producing three-dimensional objects by means of electromagnetic radiation and applying an absorber by inkjet method|

---

US7399571B2|2005-05-06|2008-07-15|General Electric Company|Multilayered articles and method of manufacture thereof|

---

US20070241482A1|2006-04-06|2007-10-18|Z Corporation|Production of three-dimensional objects by use of electromagnetic radiation|

---

US7972426B2|2007-05-09|2011-07-05|Hewlett-Packard Development Company, L.P.|Printed security mark|

---

JP5757749B2|2010-05-19|2015-07-29|富士フイルム株式会社|Polymerizable composition|

---

US8651190B2|2010-10-28|2014-02-18|Hydril Usa Manufacturing Llc|Shear boost triggering and bottle reducing system and method|

---

KR20150081446A|2012-11-05|2015-07-14|스트라타시스 엘티디.|System and method for direct inkjet printing of 3d objects|

---

JP6020185B2|2013-01-17|2016-11-02|株式会社リコー|Ink jet recording ink, ink cartridge, ink jet recording method, ink jet recording apparatus, ink recorded matter, and method for producing ink recorded matter|

---

KR20160091323A|2013-10-17|2016-08-02|엑스제트 엘티디.|Tungsten-carbide/cobalt ink composition for 3d inkjet printing|

---

US10625469B2|2014-01-16|2020-04-21|Hewlett-Packard Development Company, L.P.|Generating three-dimensional objects|

---

WO2016048375A1|2014-09-26|2016-03-31|Hewlett-Packard Development Company, L.P.|3-dimensional printing|

---

WO2016048348A1|2014-09-26|2016-03-31|Hewlett-Packard Development Company, L.P.|Lighting for additive manufacturing|

---

EP3197668B1|2014-09-26|2020-02-12|Hewlett-Packard Development Company, L.P.|3-dimensional printing|

---

CN107206698B|2015-01-30|2021-03-12|惠普发展公司有限责任合伙企业|Method, apparatus and temperature controller for manufacturing three-dimensional object|

---

JP2016168704A|2015-03-12|2016-09-23|セイコーエプソン株式会社|Three-dimensional molding apparatus, production method, and computer program|US20110123783A1|2009-11-23|2011-05-26|David Sherrer|Multilayer build processses and devices thereof|

---

CN110869191A|2017-07-10|2020-03-06|惠普发展公司，有限责任合伙企业|Fusion inhibitor containing colorant|

---

US10319654B1|2017-12-01|2019-06-11|Cubic Corporation|Integrated chip scale packages|

---

EP3581371B1|2018-06-14|2021-04-14|Fundació Institut de Ciències Fotòniques|A method and a system for self-repairing an object|

---

WO2019245534A1|2018-06-19|2019-12-26|Hewlett-Packard Development Company, L.P.|Three-dimensional printing|

---

US20210362405A1|2018-06-25|2021-11-25|Hewlett-Packard Development Company, L.P.|Three-dimensional printing|

---

CN112020417A|2018-07-31|2020-12-01|惠普发展公司，有限责任合伙企业|Temperature control in an additive manufacturing system|

---

US20210162662A1|2018-08-23|2021-06-03|Hewlett-Packard Development Company, L.P.|Anomolous nozzle determination based on thermal characteristic|

---

KR102136574B1|2018-09-28|2020-07-22|한국생산기술연구원|Binder composition for a 3D printer comprising benzoxazine derivative, and manufacturing method of binder for 3D printer|

---

US20210402684A1|2019-03-21|2021-12-30|Hewlett-Packard Development Company, L.P.|Three-dimensional printing|

---

WO2020222819A1|2019-04-30|2020-11-05|Hewlett-Packard Development Company, L.P.|Colored object generation|

---

WO2021054960A1|2019-09-19|2021-03-25|Hewlett-Packard Development Company, L.P.|Three-dimensional printing|

---

WO2021118584A1|2019-12-13|2021-06-17|Hewlett-Packard Development Company, L.P.|Three-dimensional printing with detector solutions|

---

WO2021183096A1|2020-03-09|2021-09-16|Hewlett-Packard Development Company, L.P.|Three-dimensional printing with charged yellow water-soluble dye-based fusing agent|

---

US11110650B1|2020-10-02|2021-09-07|Intrepid Automation|Vat-based additive manufacturing with dispensed material|

法律状态:
2020-03-10| B06U| Preliminary requirement: requests with searches performed by other patent offices: procedure suspended [chapter 6.21 patent gazette]|

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2020-06-30| B25G| Requested change of headquarter approved|Owner name: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P. (US) |

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2021-08-24| B350| Update of information on the portal [chapter 15.35 patent gazette]|

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2021-12-28| B09A| Decision: intention to grant [chapter 9.1 patent gazette]|

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2022-02-01| B16A| Patent or certificate of addition of invention granted [chapter 16.1 patent gazette]|Free format text: PRAZO DE VALIDADE: 20 (VINTE) ANOS CONTADOS A PARTIR DE 25/10/2016, OBSERVADAS AS CONDICOES LEGAIS. |

优先权:

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申请号 | 申请日 | 专利标题

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PCT/US2016/058684|WO2018080456A1|2016-10-25|2016-10-25|Three-dimensionalprinting|

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