Full-color 3D printing method and device

Abstract

The full-color 3D printing method comprises the following steps that corresponding three-dimensional models are established according to different workpieces, and color options of different color block outlines are configured according to the color requirements of the workpieces; the established three-dimensional model configured with color distinguishing is imported into slicing software, and an original G code used for 3D printing is generated; preparing low-viscosity light-cured resins with different colors, and filling the low-viscosity light-cured resins into corresponding ink boxes of the ink-jet printer; a 3D printing original G code is called, and first-layer printing of the workpiece is completed; the outer contour edge of the first layer of the workpiece is subjected to ink-jet printing, and the low-viscosity light-cured resin meeting the color block contour requirement adheres to the outer contour edge of the workpiece; carrying out primary curing by adopting an ultraviolet lamp; the steps are repeated until workpiece printing is completed, and a formed part is obtained; and the formed part is subjected to secondary curing treatment. According to the full-color 3D printing method provided by the invention, full-color 3D printing is realized at relatively low cost, and the coloring material and the printing matrix material are well combined through in-situ curing of the low-viscosity light-cured resin. The invention further provides a full-color 3D printing device.

Description

Technical Field

[0001] This invention relates to the field of 3D printing technology, and more specifically to a full-color 3D printing method and apparatus. Background Technology

[0002] FDM (Fused Deposition Modeling) generally refers to a technology where thermoplastic materials are heated and melted inside a nozzle, and then stacked layer by layer to form the desired shape of a sample. Traditional FDM-based multicolor 3D printing often only has several different print heads or different filament delivery channels, and the final product only has a few independent colors. In contrast, the full-color industrial-grade 3D printers that have emerged in the last two years, such as those for 3D printing portraits, often suffer from high costs and long production cycles. Water-based inks also have difficulty bonding well with the substrate. These factors have greatly hindered the development of full-color 3D printing.

[0003] Therefore, developing a new full-color 3D printing process is of great significance. Summary of the Invention

[0004] The purpose of this invention is to provide a full-color 3D printing method that achieves full-color 3D printing at a relatively low cost. By using low-viscosity photocurable resin for in-situ curing, a good bond is achieved between the coloring material and the printing substrate material.

[0005] The technical solution of the present invention is as follows:

[0006] A full-color 3D printing method includes the following steps:

[0007] Step S1: Establish corresponding 3D models for different workpieces, and configure color options for different color block outlines according to the workpiece color requirements;

[0008] Step S2: Import the established 3D model with color differentiation into the slicing software, change the slicing parameters to adjust the 3D printing process parameters, and set the inkjet printing process parameters to achieve inkjet printing on the outer contour edge of the corresponding layer height of the workpiece in the gap between printing layers, generating the original G code for 3D printing.

[0009] Step S3: Prepare low-viscosity UV-curable resins of different colors and fill them into the corresponding inkjet printer cartridges. The low-viscosity UV-curable resins include the following components by weight:

[0010] 60-80 parts prepolymer, 10-20 parts reactive diluent, 2-8 parts photoinitiator, and 1-2 parts additives;

[0011] Step S4: Retrieve the original 3D printing G-code generated in step S2 to complete the first layer printing of the workpiece;

[0012] Step S5: Adjust the ratio of low-viscosity photocurable resin of different colors in the inkjet printer cartridge according to the outline color of the first layer of the workpiece, and perform inkjet printing on the outer contour edge of the first layer of the workpiece according to the designed inkjet printing process parameters, so that the low-viscosity photocurable resin that meets the outline requirements of the color block adheres to the outer contour edge of the workpiece.

[0013] Step S6: Use a UV lamp for one-time curing to cure the colored UV-curable resin in situ at the edge of the workpiece contour.

[0014] Step S7: Print the workpiece layer by layer, and repeat steps S5-S6 to print the outer contour edge of the corresponding layer with inkjet ink and cure it until the workpiece printing is completed and the shaped part is obtained.

[0015] Step S8: Perform a secondary curing process on the molded part.

[0016] Furthermore, in step S1, the 3D model format is one of STL, STEP, or OBJ.

[0017] Furthermore, in step S2, the slicing software used is one of Cura, Slic3r, or Prusa.

[0018] Furthermore, in step S2, the process parameters for 3D printing include printing temperature, layer height, the motion trajectory of the printing nozzle or printing platform, and the motion speed.

[0019] Furthermore, in step S2, the inkjet printing process parameters include inkjet thickness, inkjet printer cartridge printhead height, inkjet printhead or printing platform movement trajectory, and inkjet color ratio.

[0020] Furthermore, in step S3, the low-viscosity photocurable resin colors include cyan, magenta, black, and yellow. The workpiece outline color is configured by adjusting the proportion of low-viscosity photocurable resin of different colors.

[0021] Furthermore, in step S5, the thickness of the photocurable resin layer formed on the outer contour edge of the workpiece is 20-60 μm.

[0022] Furthermore, the UV light frequency used for the secondary curing is the same as that used for the primary curing.

[0023] Furthermore, secondary curing is carried out in a curing chamber with a power of 400-2000W.

[0024] The present invention also provides a full-color 3D printing apparatus, including a frame, a printing platform disposed on the frame, a printing nozzle located above the printing platform, an inkjet printing cartridge disposed on the frame, a cartridge printhead connected to the inkjet printing cartridge pipeline, an ultraviolet curing device disposed on the frame, a first drive device disposed on the frame for adjusting the movement trajectory of the printing platform or the printing nozzle, a second drive device disposed on the frame for adjusting the movement trajectory of the cartridge printhead, and a control device. The inkjet printing cartridges are multiple, each filled with a different color of low-viscosity UV-curable resin, and the cartridge printhead is used to apply inkjet color layer by layer to the outer contour edge of the workpiece.

[0025] Compared with the prior art, the full-color 3D printing method and apparatus provided by the present invention have the following advantages:

[0026] I. The full-color 3D printing method provided by this invention combines inkjet printing with 3D printing. Different colors of low-viscosity photocurable resin are filled into the ink cartridge of the inkjet printer to achieve inkjet coloring of the outer contour edge of the workpiece. Full-color 3D printing is achieved at a relatively low cost. Through the in-situ curing of the low-viscosity photocurable resin, the coloring material and the printing substrate material have a good bond.

[0027] Second, in the full-color 3D printing method provided by this invention, the photocurable resin, which serves as the coloring material for the outer contour edge of the workpiece, plays a role in filling the inherent layer texture during the FDM printing process during the in-situ curing process, thereby improving the surface quality of the workpiece. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the full-color 3D printing device of the present invention. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, and to make the above-mentioned objectives, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be further described below.

[0031] It should be noted that the descriptions of these embodiments are for the purpose of aiding understanding the present invention, but do not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0032] Please see Figure 1 This is a schematic diagram of the structure of the full-color 3D printing apparatus of the present invention. The full-color 3D printing apparatus of the present invention includes a frame 1, a printing platform 2 disposed on the frame 1, a printing nozzle 3 located above the printing platform 2, an inkjet printing cartridge 4 disposed on the frame, a cartridge printhead 5 connected to the inkjet printing cartridge 4 by tubing, an ultraviolet curing device 6 disposed on the frame, a first drive device 7 disposed on the frame for adjusting the movement trajectory of the printing platform or the printing nozzle, a second drive device (not shown) disposed on the frame for adjusting the movement trajectory of the cartridge printhead, and a control device (not shown).

[0033] In this invention, the printing nozzle 3 is an FDM nozzle. The thermoplastic material is heated and melted inside the printing nozzle, and the workpiece is printed layer by layer on the printing platform 2 according to the process parameters designed in the 3D printing program. During the printing process, the printing platform 2 can move according to the set program while the printing nozzle 3 remains stationary, or the printing platform 2 can remain stationary while the printing nozzle 3 moves according to the set program. Correspondingly, the first driving device 7 controls the printing platform 2 or the printing nozzle 3 to move according to the designed motion trajectory. Specifically, the first driving device 7 is used to drive the printing platform 2 or the printing nozzle 3 to move in the X-axis, Y-axis, and Z-axis directions.

[0034] In this invention, inkjet printer cartridge 4 is used to fill different colors of low-viscosity UV-curable resin. During the printing process, ink is sprayed layer by layer onto the outer contour edge of the workpiece through the cartridge nozzle 5, causing the low-viscosity UV-curable resin to adhere to the outer contour edge of the workpiece, thereby coloring the workpiece. In this embodiment, there are four inkjet printer cartridges, each filled with a different color of low-viscosity UV-curable resin. Specifically, the four colors of the low-viscosity UV-curable resin are consistent with the colors of the inkjet printer cartridges, namely C (Cyan), M (Magenta), K (Key), and Y (Yellow). The proportions of each low-viscosity UV-curable resin are adjusted according to the color of the workpiece contour to ensure that the output color matches the color of the workpiece contour.

[0035] The ink cartridge printhead 5 is used to spray UV-cured resin material onto the outer contour edge of the workpiece; therefore, the motion trajectory of the ink cartridge printhead 5 needs to be designed and adjusted. Specifically, the ink cartridge printhead 5 is driven by a second drive device to complete its movement in the X, Y, and Z axis directions.

[0036] The ultraviolet curing device 6 is used to cure the workpiece after it has been coated with UV-curing resin. Specifically, the ultraviolet curing device is an ultraviolet lamp.

[0037] The control device is used to control the movement trajectory of the printing nozzle or printing platform and make it work according to the designed process parameters; to control the movement trajectory of the ink cartridge printhead and control the output of various colors of UV-curable resin in the inkjet printing cartridge according to the inkjet printing process parameters; and to control the working status of the UV curing device according to the working stage.

[0038] This invention relates to a full-color 3D printing device that combines inkjet printing with FDM 3D printing. It uses inkjet printing to color the edges of the workpiece's outer contour. Compared to traditional multi-color 3D printers, which only have multiple print heads or simply mechanically mix a few colors, resulting in monotonous colors and uneven mixing, this invention's full-color 3D printing device achieves precise control over the entire color range. Compared to expensive industrial-grade full-color inkjet 3D printers, this invention's full-color 3D printing device only requires adding inkjet cartridges to a traditional small commercial FDM printer, enabling full-color 3D printing at a relatively low cost.

[0039] The full-color 3D printing method of the present invention includes the following steps:

[0040] Step S1: Establish corresponding 3D models for different workpieces, and configure color options for different color block outlines according to the workpiece color requirements;

[0041] Specifically, the 3D model format is one of STL, STEP, or OBJ;

[0042] Step S2: Import the established 3D model with color differentiation into the slicing software, change the slicing parameters to adjust the 3D printing process parameters, and set the inkjet printing process parameters to achieve inkjet printing on the outer contour edge of the corresponding layer height of the workpiece in the gap between printing layers, generating the original G code for 3D printing.

[0043] Specifically, the slicing software used is one of Cura, Slic3r, or Prusa; the process parameters for 3D printing include printing temperature, layer height, the movement trajectory of the printing nozzle or printing platform, and travel speed; the process parameters for inkjet printing include inkjet thickness, inkjet printer cartridge nozzle height, the movement trajectory of the inkjet cartridge nozzle or printing platform, and color matching.

[0044] Step S3: Prepare low-viscosity UV-curable resins of different colors and fill them into the corresponding inkjet printer cartridges. The low-viscosity UV-curable resins include the following components by weight:

[0045] 60-80 parts prepolymer, 10-20 parts reactive diluent, 2-8 parts photoinitiator, and 1-2 parts additives;

[0046] The low-viscosity photocurable resin has a viscosity below 50 mPa·s and exhibits good adhesion to the substrate material used for printing the workpiece. Preferably, the prepolymer is a small molecule of epoxy resin or acrylate.

[0047] The colors of the low-viscosity UV-curable resin are consistent with the ink cartridge colors of the inkjet printer, namely C (Cyan), M (Magenta), K (Key), and Y (Yellow).

[0048] Step S4: Retrieve the original 3D printing G-code generated in step S2 to complete the first layer printing of the workpiece;

[0049] Specifically, the substrate materials used for printing workpieces are transparent, translucent, or milky white PLA, PETG, ABS, etc.

[0050] Step S5: Adjust the ratio of low-viscosity photocurable resin of different colors in the inkjet printer cartridge according to the outline color of the first layer of the workpiece, and perform inkjet printing on the outer outline edge of the first layer of the workpiece according to the designed inkjet printing process parameters, so that the low-viscosity photocurable resin that meets the outline requirements of the color block adheres to the outer outline edge of the workpiece; at this time, the thickness of the photocurable resin layer formed on the outer outline edge of the workpiece is 20-60um, and its width matches the layer height of the workpiece.

[0051] Step S6: Use a UV lamp for one-time curing to cure the colored UV-curable resin in situ at the edge of the workpiece contour.

[0052] Step S7: Print the workpiece layer by layer, and repeat steps S5-S6 to print the outer contour edge of the corresponding layer with inkjet ink and cure it until the workpiece printing is completed and the shaped part is obtained.

[0053] Step S8 involves performing a secondary curing process on the molded part to ensure that the resin material that was not fully cured during the first curing process is fully cured.

[0054] To ensure the same photocuring reaction, the ultraviolet light frequency used for the secondary curing is the same as that used for the primary curing, and the light intensity for the secondary curing is greater than that for the primary curing, thus ensuring the effectiveness of the secondary curing. In this invention, the secondary curing is carried out in a curing chamber with a power of 400-2000W.

[0055] The full-color 3D printing method provided by this invention combines an inkjet printing cartridge with an FDM printing nozzle. Different colors of low-viscosity photocurable resin are filled into the printing cartridge to color the outer contour edges of the workpiece. This achieves full-color 3D printing at a relatively low cost. The in-situ curing of the low-viscosity photocurable resin ensures good bonding between the coloring material and the printing substrate material. The photocurable resin, as the coloring material for the outer contour edges of the workpiece, fills in the inherent layer textures present during FDM printing, improving the surface quality of the workpiece.

[0056] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions, and variations made to these embodiments without departing from the principles and spirit of the present invention still fall within the protection scope of the present invention.

Claims

1. A full-color 3D printing method, characterized in that, Includes the following steps: Step S1: Establish corresponding 3D models for different workpieces, and configure color options for different color block outlines according to the workpiece color requirements; Step S2: Import the established 3D model with color differentiation into the slicing software, change the slicing parameters to adjust the 3D printing process parameters, and set the inkjet printing process parameters to achieve inkjet printing on the outer contour edge of the corresponding layer height of the workpiece in the gap between printing layers, generating the original G code for 3D printing. Step S3: Prepare low-viscosity UV-curable resins of different colors and fill them into the corresponding inkjet printer cartridges. The low-viscosity UV-curable resins include the following components by weight: 60-80 parts prepolymer, 10-20 parts reactive diluent, 2-8 parts photoinitiator, and 1-2 parts additives; Step S4: Retrieve the original 3D printing G-code generated in step S2 to complete the first layer printing of the workpiece; Step S5: Adjust the ratio of low-viscosity photocurable resin of different colors in the inkjet printer cartridge according to the outline color of the first layer of the workpiece, and perform inkjet printing on the outer contour edge of the first layer of the workpiece according to the designed inkjet printing process parameters, so that the low-viscosity photocurable resin that meets the outline requirements of the color block adheres to the outer contour edge of the workpiece. Step S6: Use a UV lamp for one-time curing to cure the colored UV-curable resin in situ at the edge of the workpiece contour. Step S7: Print the workpiece layer by layer, and repeat steps S5-S6 to print the outer contour edge of the corresponding layer with inkjet ink and cure it until the workpiece printing is completed and the shaped part is obtained. Step S8: Perform a secondary curing process on the molded part.

2. The full-color 3D printing method according to claim 1, characterized in that, In step S1, the 3D model format is one of STL, STEP, or OBJ.

3. The full-color 3D printing method according to claim 1, characterized in that, In step S2, the slicing software used is one of Cura, Slic3r, or Prusa.

4. The full-color 3D printing method according to claim 1, characterized in that, In step S2, the 3D printing process parameters include printing temperature, layer height, the movement trajectory of the printing nozzle or printing platform, and the movement speed.

5. The full-color 3D printing method according to claim 1, characterized in that, In step S2, the inkjet printing process parameters include inkjet thickness, inkjet printer cartridge printhead height, the movement trajectory of the inkjet printhead or printing platform, and inkjet color ratio.

6. The full-color 3D printing method according to claim 1, characterized in that, In step S3, the low-viscosity photocurable resin colors include cyan, magenta, black, and yellow. The workpiece outline color is configured by adjusting the proportion of low-viscosity photocurable resin of different colors.

7. The full-color 3D printing method according to claim 1, characterized in that, In step S5, the thickness of the photocurable resin layer formed on the outer contour edge of the workpiece is 20-60 μm.

8. The full-color 3D printing method according to claim 1, characterized in that, The UV light frequency used for the secondary curing is the same as that used for the primary curing.

9. The full-color 3D printing method according to claim 8, characterized in that, The secondary curing is carried out in a curing chamber with a power of 400-2000W.

10. A full-color 3D printing device, characterized in that, The device includes a frame, a printing platform mounted on the frame, printing nozzles located above the printing platform, inkjet printing cartridges mounted on the frame, inkjet printheads connected to the inkjet printing cartridges via tubing, a UV curing device mounted on the frame, a first drive device mounted on the frame for adjusting the movement trajectory of the printing platform or the printing nozzles, a second drive device mounted on the frame for adjusting the movement trajectory of the inkjet printheads, and a control device. Multiple inkjet printing cartridges are used to fill different colors of low-viscosity UV-curable resin, and the inkjet printheads are used to apply inkjet coloring layer by layer to the outer contour edges of the workpiece.

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