Method for constructing multi-layer material stacking structures in three-dimensional space based on color mapping to achieve multi-color printing of three-dimensional models

Abstract

The invention discloses a method for building a multi-layer material stacking structure in a three-dimensional space based on color mapping to achieve three-dimensional model multi-color printing, and belongs to the technical field of 3D printing. The method aims at solving the problem that the color gamut of an existing FDM printing technology is limited. The core of the method is that after a three-dimensional model with a color map is obtained, a multi-layer stacking scheme composed of multiple preset basic color semitransparent materials is calculated through a color decomposition algorithm according to each target color on the map; according to the scheme, generating a multi-layer developing structure with physical thickness along the normal direction of the surface of the model, and converting the multi-layer developing structure into a printing path file (G-code) containing a multi-material switching instruction; and finally, the 3D printer executes printing according to the path file. Two-dimensional color information is mapped into a material stacking structure in a three-dimensional space, the transmission color mixing effect of materials is utilized, the color gamut is greatly expanded under a limited base material, and the method has the advantages of being low in cost and high in compatibility.

Description

(19) State Intellectual Property Office (12) Invention Patent Application (10) Application Publication Number (43) Application Publication Date (21) Application Number 202511464982.4 (22) Application Date 2025.10.14 (71) Applicant Jin Yu Address 3304, Building 5, Phase I, Greenland, Huashan District, Ma'anshan City, Anhui Province 243000 (72) Inventor Jin Yu Liao Xin (51) Int.Cl. B29C 64 / 118 (2017.01) B29C 64 / 393 (2017.01) B33Y 10 / 00 (2015.01) B33Y 50 / 02 (2015.01) (54) Invention Title: A Method for Multi-Color Printing of 3D Models by Constructing Multi-Layer Material Stacking Structures in 3D Space Based on Color Mapping (57) Abstract: This invention discloses a method for multi-color printing of 3D models by constructing multi-layer material stacking structures in 3D space based on color mapping, belonging to the field of 3D printing technology. This method aims to solve the problem of limited color gamut in existing FDM printing technology. Its core is: after obtaining a 3D model with color mapping, for each target color on the mapping, a multi-layer stacking scheme composed of multiple preset basic color translucent materials is calculated through a color decomposition algorithm; then, according to the scheme, a multi-layer color display structure with physical thickness is generated along the normal direction of the model surface, and converted into a printing path file (G-code) containing multi-material switching instructions; finally, the 3D printer executes printing according to the path file. This invention maps two-dimensional color information to a material stacking structure in three-dimensional space, and utilizes the transmission color mixing effect of materials to achieve a great expansion of the color gamut under limited basic materials, with the advantages of low cost and high compatibility. Claims 1 page, Description 3 pages, Drawings 3 pages, CN 121316236 A 2026.01.13 CN 1 21 31 62 36 A 1. A method for constructing a multi-layer material stacking structure in three-dimensional space based on color mapping to achieve multi-color printing of a three-dimensional model, characterized by comprising the following steps: Step 1: Obtain a three-dimensional model file and its corresponding color map, wherein the color map provides target color information for each point on the model surface; Step 2: Preset the base color material and the number of stacking layers N; Step 3: For any target color on the color map, calculate using a color decomposition algorithm to determine a multi-layer stacking sequence consisting of the base color material and containing N layers, wherein the sequence defines the type and order of the base color material used in each layer; Step 4: Based on the multi-layer stacking sequence, generate an N-layer material stacking structure along the normal direction for the surface of the three-dimensional model, and directly generate a printing path file containing multi-material printing control instructions; Step 5: Control the multi-color 3D printer to execute printing according to the printing path file to form the material stacking structure.1. The method according to claim 1, wherein the base color material in step two is one of eight semi-transparent materials: cyan, magenta, yellow, black, white, red, green, and blue. 2. The method according to claim 1, wherein the number of stacked layers N in step two is an integer between 3 and 8. 3. The method according to claim 1, wherein the thickness of each layer in the material stacking structure is 0.1 mm to 0.4 mm in step four. 4. The method according to claim 1, wherein the colored surface of the model is mainly based on the transmission color mixing effect of multiple semi-transparent materials, and a multi-layer base color stacked structure is constructed in space. 5. The method according to claim 1, wherein the printing path file is a G-code file, and the multi-material printing control command is a tool switching command for switching print heads of different base color materials. 7. A system for multi-color printing of a 3D model, characterized in that it comprises: an input module for acquiring a 3D model file and a color map corresponding to the surface of the 3D model; a layer calculation module for resolving a target color on the color map into a multi-layer stacked sequence composed of multiple preset base color materials using a color decomposition algorithm; a path generation module for generating a printing path file containing multi-material printing control instructions based on the multi-layer stacked sequence, the file being used to guide the printer to construct a multi-layer material stacked structure; and a control module for sending the printing path file to a multi-material 3D printer and controlling it to execute printing. 8. The system according to claim 7, characterized in that the layer calculation module is configured to use 8 base color materials and 3 to 8 stacked layers to determine the multi-layer stacked sequence. 9. The system according to claim 7, characterized in that the path generation module sets the thickness of each layer of material in the multi-layer stacked structure to 0.1 mm to 0.4 mm when generating the printing path file. Claims 1 / 1 Page 2 CN 121316236 A A method for multi-layer material stacking structure based on color mapping in three-dimensional space to achieve multi-color printing of three-dimensional models Technical Field

[0001] This invention belongs to the field of 3D printing technology, specifically, it relates to a fused deposition modeling (FDM) printing method that utilizes multi-layer material stacking to achieve rich color expression, especially suitable for processing three-dimensional models with complex color mapping. Background Art

[0002] Fused deposition modeling (FDM) 3D printing technology has been widely used in manufacturing and personal consumer fields due to its advantages such as customized production capabilities, rapid prototyping, and strong material versatility. However, in terms of achieving multi-color or full-color printing, standardQuasi-FDM technology has inherent limitations. Existing multi-color FDM solutions mainly fall into two categories: The first is surface coloring technology, which involves printing a monochrome or white model first, and then applying color to the model's surface using inkjet or other methods. The color in this solution only adheres to the surface layer, and the printing equipment requires additional color nozzles and technical support. The second is color mixing extrusion technology, which generates the target color in real time by mixing multiple base pigments at the print head. The color performance of this solution is limited by the types of consumable colors the printer can mix simultaneously and the precision of the color mixing mechanism, resulting in a limited color gamut, harsh color transitions, and potential issues such as color bleeding and printhead clogging. To address these issues, some advanced solutions exist, such as manual coloring after printing or using expensive full-color inkjet / binder jetting 3D printing technology. These solutions generally suffer from high costs, complex processes, or the need for additional post-processing, contradicting the core advantages of FDM technology: low cost and rapid prototyping. Therefore, developing a technology that can significantly expand the color performance range on standard multi-color FDM printers at low cost has significant market value and practical significance.

[0003] The purpose of this invention is to solve the problem of limited color printing in existing FDM technology and to provide a method for multi-color printing of three-dimensional models based on multi-layer material stacking. This method, through an algorithm-driven, structured color rendering approach, enables multi-material FDM printers to display a richer range of colors than the number of basic consumables on a mature hardware platform.

[0004] To achieve the above objective, this invention adopts the following technical solution: A method for multi-color printing of three-dimensional models based on multi-layer material stacking, the core idea of ​​which is "algorithm decomposition, structured color rendering". This method transforms the complex color matching problem into a definite material stacking problem, specifically including the following steps: Step 1: Obtain a three-dimensional model with a color map. The color map provides a point-by-point target color definition for the model surface; Step 2: Preset the basic printing materials and the number of stacking layers. Select a set (e.g., 8 kinds) of basic color consumables with good translucency properties and set a fixed number of stacking layers N (e.g., 4 layers); Step 3: Perform color decomposition calculation. For each target color on the color map, the system calculates the optimal multi-layer stacking sequence through a core color decomposition algorithm. This sequence specifies the types and order of base materials to be used in each of the N layers, ensuring that the color produced by the mixing of light transmission after stacking these N layers is closest to the target color; Instruction manual, page 1 / 3, CN 121316236 A. Step 4: Generate multi-layer structure and printing path. Based on the calculated stacking sequence, the software "dresses" the model surface with an N-layer structure and a physical thickness of "colored shell" along the normal direction of the model surface; Step 5: Perform multi-material printing. The multi-material FDM printer precisely prints on the model according to the instructions in the G-code.Different base color materials are stacked layer by layer on the surface to eventually form a physical entity.

[0005] The advantages of the present invention are: 1) Greatly expand the color gamut: By stacking M kinds of base consumables in N layers, M^N color combinations can be theoretically achieved, realizing an exponential expansion of the color gamut; 2) Cost and cost-effectiveness advantages: This method is mainly based on software and algorithms, without requiring any hardware modification to existing FDM printers, and is compatible with various commercially available semi-transparent printing consumables; 3) Structural color rendering with unique effects: Colors are generated by material structures with physical depth, and the color rendering has a sense of layering and transparency. Brief Description of the Drawings

[0006] Figure 1 is an overall flowchart of an embodiment of the method of the present invention; Figure 2 is a schematic diagram of the principle of the color decomposition algorithm of the present invention; Figure 3 is a final effect display of an embodiment of the present invention. Detailed Description of the Embodiments

[0007] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0008] Referring to Figure 1, a complete implementation process of the present invention is as follows: S1: Obtain and process the target model. The user inputs a 3D model file with color textures. In this embodiment, a cuboid model (OBJ format) with multiple color gradients on its surface and its corresponding color texture (PNG format) are selected.

[0009] S2: Parameter settings. In the printing software, the printing parameters are set. In this embodiment, a set of translucent PETG consumables containing eight basic colors is selected, specifically: cyan (C), magenta (M), yellow (Y), white (W), black (K), red (R), green (G), and blue (B). The number of stacked layers of the color rendering structure is set to N=4, and the thickness of each layer is 0.2mm.

[0010] S3: Color decomposition and scheme generation. Referring to Figure 2, the software starts processing the color texture. For a dark blue pixel (target color) on the texture, the color decomposition algorithm is started. The goal of this algorithm is to find a stacked sequence composed of four basic materials that makes its optical effect closest to the target dark blue. For example, the algorithm might determine the optimal sequence as: [Layer 1: Blue, Layer 2: Cyan, Layer 3: Black, Layer 4: Transparent / White]; Similarly, for a green pixel on the texture, the algorithm might output another sequence, such as [Layer 1: Yellow, Layer 2: Cyan, Layer 3: Yellow, Layer 4: White]; This calculation process traverses all areas on the texture, generating a unique 4-layer material stack "recipe" for the entire texture.

[0011] S4: Generating Multilayer Structure and Printing Path The path generation module starts constructing the geometry based on the stacking scheme obtained in step S3. For each triangular facet on the model surface, it creates 4 offset faces outward (or inward) along its normal direction, forming a thickness of 0.8mm (4 * ...A thin shell (0.2mm). This thin shell is logically divided into 4 layers, each of which is assigned the corresponding material properties calculated in step S3; the slicing engine then slices this model (main body + colored thin shell) with complete material information to generate the final printing G-code. This G-code file contains the movement path of the print head in XYZ space, as well as the instructions for switching materials when printing different layers and different areas of the colored thin shell.

[0012] S5: Perform layered printing and send the generated G-code file to an FDM printer that supports 8 materials. The printer starts working according to the G-code instructions. When printing the outer surface of the cuboid model, the printer will use blue material in the first layer in the dark blue area and yellow material in the first layer in the green area according to the instructions; when printing the second layer, it will switch to cyan material in the dark blue area and cyan material in the green area... and so on, until all 4 layers of color structure and the main body of the model are printed.

[0013] The final mixed-color cuboid is formed by the mixing of four layers of semi-transparent materials, and the color expression is greatly enriched.

[0014] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention. Specification 3 / 3 pages 5 CN 121316236 A Figure 1 Specification Figure 1 / 3 pages 6 CN 121316236 A Figure 2 Specification Figure 2 / 3 pages 7 CN 121316236 A Figure 3 Specification Figure 3 / 3 pages 8 CN 121316236 A 1 A Method for Constructing Multi-Layer Material Stacking Structures in Three-Dimensional Space Based on Color Mapping to Achieve Multi-Color Printing of Three-Dimensional Models Abstract This invention discloses a method for constructing multi-layer material stacking structures in three-dimensional space based on color mapping to achieve multi-color printing of three-dimensional models, belonging to the field of 3D printing technology. This method aims to solve the problem of limited color gamut in existing FDM printing technology. The core of this invention lies in the following: After acquiring a 3D model with color textures, for each target color on the texture, a color decomposition algorithm is used to calculate a multi-layered stacking scheme composed of various preset base-color translucent materials. Subsequently, based on this scheme, a multi-layered color-displaying structure with physical thickness is generated along the normal direction of the model surface and converted into a printing path file (G-code) containing multi-material switching instructions. Finally, the 3D printer executes printing based on this path file. This invention maps two-dimensional color information to a material stacking structure in three-dimensional space, utilizing the transmission and color mixing effect of materials to achieve a significant expansion of the color gamut with limited base materials, offering advantages such as low cost and high compatibility.multi-layer material stacking structures in three-dimensional space based on color mapping to achieve multi-color printing of three-dimensional models Abstract The invention discloses a method for constructing multi-layer material stacking structures in three-dimensional space based on color mapping to achieve multi-color printing of three-dimensional models, and belongs to the technical field of 3D printing. This method aims to solve the problem of limited color gamut of the existing FDM printing technology. The core lies in: after acquiring a three-dimensional model with a color map, for each target color on the map, a multi-layer stacking scheme composed of multiple preset basic-color translucent materials is calculated by a color decomposition algorithm. Thereafter, according to the scheme, a multi-layer color rendering structure with physical thickness is generated along the normal direction of the model surface, and converted into a printing path file (G-code) containingmulti-material switching instructions. Finally, the 3D printer performs printing according to the path file. By mapping two-dimensional color information into a material stacking structure in a three-dimensional space, the present invention utilizes the transmissive color mixing effect of materials to achieve a great expansion of the color gamut with limited basic materials, and has the advantages of low cost and high compatibility.

Claims

1. A method for multi-color printing of a three-dimensional model based on color map to construct a multi-layer material stack structure in a three-dimensional space, the method comprising: The method comprises the following steps: ​ Step one, obtaining a three-dimensional model file and a color map corresponding thereto, the color map providing target color information of each point on the model surface; Step two, presetting a base color material and a number N of stacking layers; Step three, for any target color on the color map, a multi-layer stacking sequence composed of the base color material and containing N levels is determined through color decomposition algorithm, the sequence defining the type and order of the base color material used by each level; Step four, based on the multi-layer stacking sequence, an N-layer material stacking structure along the normal direction is generated for the three-dimensional model surface, and a printing path file containing multi-material printing control instructions is directly generated; Step five, controlling a multi-color 3D printer to perform printing according to the printing path file to form the material stacking structure, so as to realize the target color through the optical superposition effect of multi-layer materials.

2. The method of claim 1, wherein, In step two, the base color material is eight kinds of translucent materials, namely cyan, magenta, yellow, black, white, red, green and blue materials.

3. The method of claim 1, wherein, In step two, the number N of stacking layers is an integer between 3 and 8.

4. The method of claim 1, wherein, In step four, the thickness of each level in the material stacking structure is 0.1-0.4 mm.

5. The method of claim 1, wherein, The colored surface of the model is mainly realized by constructing a multi-layer base color stacking structure in space based on the transmission and mixing effect of multi-layer translucent materials.

6. The method of claim 1, wherein, The printing path file is a G-code file, and the multi-material printing control instruction is a tool switching instruction for switching different base color material printing heads.

7. A system for enabling multi-color printing of a three-dimensional model, the system comprising: The method comprises: An input module for obtaining a three-dimensional model file and a color map corresponding to the three-dimensional model surface; A layer calculation module for analyzing a multi-layer stacking sequence composed of multiple preset base color materials into a multi-layer stacking sequence through a color decomposition algorithm for a target color on the color map; A path generation module for generating a printing path file containing multi-material printing control instructions according to the multi-layer stacking sequence, the file being used to guide a printing mechanism to build a multi-layer material stacking structure; A control module for sending the printing path file to a multi-material three-dimensional printer and controlling it to perform printing.

8. The system of claim 7, wherein, The layer calculation module is configured to use eight base color materials and a number N of stacking layers between 3 and 8 to determine the multi-layer stacking sequence.

9. The system of claim 7, wherein, When generating the printing path file, the path generation module sets the thickness of each layer of material in the multi-layer stacking structure to 0.1-0.4 mm.

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