3D Printer Capable of Strong Full-Color Resin Composite
Background
Custom-made products, such as dentures and eyeglass frames, must be of high quality. The production of such products comprises many processes that depend on manual labor, which is time-consuming (and costly). Consequently, the use of a 3D printer to produce custom-made items is now being considered. However, the 3D printing technology to date has only been able to create monochromatic products, so poor esthetics (a poor visual appearance) has been a problem.
Solutions
Inkjet 3D printers (featuring material jetting) using UV-curable resin offer a method for the full-color formation of custom-made products with high esthetic appeal. However, items created with this method are not very strong, so its application has been limited to design prototyping.
To address this problem, Ricoh has used its integrated original technology for the ink and the process to improve the strength of the material-jetting method and realize the shift to full-color production. With this technology, it is possible to create 3D printers that simultaneously realize strong, precise, and full color products.
Technical highlights
1. Full-color production technology for ink with filler (particle) additives
The technical overview is as shown in the figure below. The addition of a filler (filling material particles) to the ink greatly increases its strength, at the same time, the ink retains the physical properties that allow it to be ejected by inkjet printheads. The main inks used are strong, white ink and high-transparency ink (clear ink), which both contain the filler. Color ink is then arranged in small quantities at high concentrations to achieve both strength and color. In addition, the items formed are expected to be extremely safe due to their optimization using monomer formulation technology.
Figure 1. Overview of the forming technology
2. Strength and esthetics
It is possible to produce strong items at a level applicable to dentures. In addition, as it is possible to simultaneously form components of different colors all at once, it is possible to express a high level of esthetic beauty by using full color. (Figure 2)
Figure 2. Items formed (batch formation of dentures)
Printing the color ink in small drops (small quantities) makes it possible to draw with high precision. (Figure 3)
Figure 3. Fineness of the printing (drawing with color ink inside a clear item formed with 1mm thickness)
Ricoh's vision
Ricoh is utilizing the three key technologies of inkjet printhead technology, ink supply technology, and printing system technology that the company has cultivated over many years and is aiming to apply and expand these technologies to create new value with a “digital transformation in manufacturing" that changes the conventional wisdom. The use of 3D printers is expected to shorten manufacturing processes and make it possible to perform complex manufacturing processes in a single step, for the easy production of high-quality products with only the minimal resources necessary. However, the current reality is that each method has various limitations. It has previously been difficult to produce items that are complex and highly esthetic, but this technology will make the production of such items possible with strength, durability, and efficiency. We will continue to develop this technology to help realize a decarbonized and recycling-oriented society.