Colored 3D Object Fabrication via Layer-Structure and Color Ink Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for fabricating fully-colored 3D objects using rapid molding technologies face challenges such as uneven surfaces and dimensional inaccuracies due to differences in material properties like viscosity and shrinkage ratios, and are limited by the number of colors that can be printed, leading to high manufacturing costs.
Innovation Solution
A method and system for layer-by-layer printing of colored 3D objects using a single type of photosensitive resin material with Eco solvent inks, where the molding material is ejected using a variable-frequency ejection method, and color inks are printed at locations where the molding material is not ejected, allowing for improved dimensional accuracy and reduced costs by avoiding the need for multiple materials with similar shrinkage ratios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple color photocurable resins are used to print fully-colored 3D objects, then the color gamut is improved, but the dimensional accuracy deteriorates due to inconsistent shrinkage ratios
Solution Approach 1:
The patent separates the structure printing and color printing into two distinct stages: first printing the structural layer using a single-material photocurable resin, then selectively printing color inks on specific regions. This segmentation allows each stage to optimize for its specific function without compromising the other.
Solution Approach 2:
The patent introduces a white photocurable resin as an intermediary base layer that provides a uniform shrinkage reference. Color inks are then printed on this white base, allowing the white resin to act as a mediator that compensates for potential dimensional variations while enabling full-color printing.
2Adaptability or versatility
If multiple color photocurable resins with different material properties are used, then the color gamut is improved, but the surface uniformity deteriorates due to inconsistent viscosity and surface tension
Solution Approach 1:
The patent divides the printing process into structure formation (using single-material photocurable resin) and color application (using Eco solvent inks on white resin base). This segmentation ensures that material property inconsistencies affect only the color layer, not the structural integrity or surface uniformity of the underlying object.
Solution Approach 2:
The patent changes the material parameter strategy by using Eco solvent inks with controlled viscosity (4-14 cps) and surface tension (22-35 mN/m) that are fundamentally different from photocurable resins. This parameter change allows color application without the dimensional and surface uniformity issues caused by varying resin properties.
3Adaptability or versatility
If multiple types of molding materials are used to achieve full-color printing, then the color gamut is improved, but the manufacturing cost increases
Solution Approach 1:
The patent replaces expensive, specialized full-color photocurable resins with a combination of inexpensive white photocurable resin and standard Eco solvent inks. This substitution uses readily available, low-cost materials to achieve the same full-color printing capability.
Solution Approach 2:
The patent makes the white photocurable resin serve multiple functions: as the structural printing material, as the color carrier base, and as the surface finish layer. This multi-functionality eliminates the need for separate specialized materials for each function, reducing overall manufacturing cost.
4Measurement precision
If color inks are printed on each pixel corresponding to one ink droplet, then the printing resolution is maintained, but the surface uniformity deteriorates due to varying droplet volumes from different color combinations
Solution Approach 1:
The patent creates a homogeneous white photocurable resin base layer that provides uniform surface properties across the entire printed object. Color inks are then applied on this uniform base, ensuring that surface uniformity is maintained regardless of the underlying color pixel composition.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables the creation of fully-colored 3D objects with improved dimensional accuracy, reduced manufacturing costs, and a wide color gamut, while minimizing bleeding and environmental impact through the use of Eco solvent inks that infiltrate into the layer-structure product.
Implementation Method 1
Because the photocurable resin materials are used, each droplet of ink ejected by the print heads can have a certain volume after cured by light.
Implementation Method 2
at least a part of the color inks infiltrates into the layer-structure product to form the layer-print product
Data Source
AI summary
A method for fabricating a colored 3D object is provided. The method includes: forming, based on layer-structure data of a target object, a layer-structure product by printing of a molding material; forming a layer-print product by printing color inks on the layer-structure product based on layer-color data; and repeatedly forming the layer-print product to provide a plurality of the layer-print products, and fabricating a colored 3D object from the plurality of the layer-print products, stacked one over another. The color inks are printed synchronously or following the formation of the layer-structure product. A system for fabricating a colored 3D object includes a processing terminal, a print head, and a drive controller. The method and system improve a dimensional accuracy and printing efficiency of the colored 3D object.