RICOH Ri 4000, which Ricoh started selling overseas in October 2023, is a DTG (direct to garment) printer that is developed to contribute to the business of users who are engaged in the printing industry such as T-shirts printing. When printing images on fabrics using a DTG printer, the pre-treatment process is required to coat the fabric with the pre-treatment liquid to improve the color developability of images. However, the conventional pre-treatment process is often performed manually, and therefore quality defects are likely to occur. RICOH Ri 4000 is a new DTG printer equipped with the inkjet heads that eject not only ink but also pre-treatment liquid to print images. We will report on the technology of RICOH Ri 4000, which solved the above problems by digitizing the pre-treatment process with inkjet.

The mechanical properties of models are crucial in determining the industrial applications of additive manufacturing (AM) techniques. Material jetting (MJT) has been primarily limited to mold-making, prototyping, etc., owing to its low strength. Ricoh Co., Ltd. has succeeded in developing a 3D Printer capable of strong full-color resin composite. To improve the strength, we optimized the filler shape, modified the surface properties, and optimized the monomer formulation of the ink. To develop a colorization process suitable for filler-added inks, we investigated a method to apply transparent ink over small-colored ink droplets. We achieved a bending strength of 180 MPa for colorless models and 177 MPa for colored models, which is remarkable compared to the typical MJT and VPP (Vat Photopolymerization) product strength of 80 MPa or less. This technology makes the direct manufacturing of production parts requiring both esthetic beauty and high strength in colors, such as artificial teeth, dentures, and eyeglass frames, more realistic.

Additive manufacturing (AM) technologies are expected as new technologies for manufacturing denture frameworks, acetabular cups, artificial hip joint stems, and femoral components and tibial trays of artificial knee joints among others. It is possible to obtain marketing approval for highly biocompatible implants that are optimized for the skeletal structures and needs of patients by combining 3D layer manufacturing technologies with imaging technologies such as computed tomography (CT).

Regenerative medicine is a research field aimed at restoring or replacing the function of tissues and organs damaged by accidents or diseases, and its social and medical significance is increasing globally. In recent years, the fabrication of three-dimensional structures using bio-3D printing technology has rapidly advanced. While 3D printers used in engineering and bio-3D printers share many technical elements, a clear distinction lies in the latter's use of cells and biomaterials combined as bioinks. This article provides an overview of regenerative medicine and bio-3D printing technology for creating tissues using cells. Furthermore, the text highlights the bio-3D printer using Kenzan method, which was developed in our laboratory. It briefly outlines the background of its development and its applications, which encompass image processing technology for system automation, and introduces animal experiments and studies involving human subjects.

Printing technology is the art of placing the right ink materials in the right places. Moreover, it is an extremely advanced technology that is the culmination of the craftsmanship and hard work of the developers. Now, in the post-iPS cell (induced pluripotent stem cell) era, the technology to construct differentiated cells and organs with unique biomaterials while positioning them in the right places, both in two and three dimensions, is increasingly needed. In addition, “Organ Engineering” involves a Post-fabrication Process, which is the process of growing and maturing the organ after it has been constructed. The need for 3D-Bioimaging technology to observe and measure 3D tissues is also increasing. 3D-Bioprinting and 3D Bioimaging in the “Organ Engineering” process is discussed based on the struggles of the research history of one researcher.

In recent years, image recognition technologies have become increasingly commoditized thanks to advances in cloud computing and open-source tools, enabling even non-experts to easily utilize high-performance recognition systems. This article provides an overview of major image recognition tasks such as image classification, object detection, pose estimation, and action recognition, and discusses how combining these technologies has expanded the range of possible applications. As a case study, we introduce a prototype application for supporting skateboard practice and examine key challenges in implementation, including the need for domain-specific data and potential solutions. We also highlight the importance of designing community-based platforms where users naturally contribute data through their interactions.