We investigate inverted organic light-emitting diodes (iOLEDs) using poly (9,9-dioctylfluorene-alt-benzothiadiazole) (F8BT) as an emissive layer and metal oxide thin films, titanium oxide (TiO₂) or zinc oxide (ZnO) as an electron-injecting layer by wet processes. The device characteristics of the iOLEDs with TiO₂ films prepared by spray pyrolysis are almost comparable to those of the iOLEDs reported in literature. iOLEDs with ZnO films were prepared by an electrochemical method. The characteristics of the iOLEDs are similar to those of the iOLEDs by spray pyrolysis reported in literature, demonstrating that the electrochemical method for the deposition of ZnO is applicable to iOLEDs. The electroluminescent characteristics of iOLEDs with ZnO are better than those with TiO₂ because of higher electron injection barrier at TiO₂/F8BT interface.

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In the current consumer market of the inkjet printer, there are the needs of higher print and/or higher resolution. Inkjet head needs the performance of the higher frequency jetting. The jetting velocity is constant in the fixed jetting frequency, but is different in low frequency and high frequency. In the real printing, the jetting interval is irregular. Therefore, the cause of the worse print quality is landing ink on the miss position by the inconstant jetting velocity. So far, the residual vibration after jetting and the ink meniscus which is not the initial state change the jetting velocity in the various jetting interval. But, these detailed principles are unclear. In this paper, we analyzed the jetting velocity fluctuation on the jetting interval the jetting ink behavior. The jetting velocity of 1 drop increased on short jetting interval by residual vibration. The jetting velocity of 2 and 3 drops decreased on short jetting interval by the ink left on the nozzle. Then, we found that the cause of jetting velocity fluctuation is the different single drop and multi drops.

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We present a fast image restoration method using the 2-D block Kalman filter with colored driving source. The proposed method has the remarkable feature that it can reduce the computational complexity using the high correlation pixels of current region and reference region, while the conventional 2-D block Kalman filter methods have been performed without considering the relationship between the reference region and the current region. We have shown the effectiveness of the proposed method by numerical results and subjective evaluation results.

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It is known that anodically-oxidized niobium (Nb) films make various colors. The driving force of coloration is considered to be thin film interference due to the Nb₂O₅ layer on the Nb film. In the case of the coloration due to thin film interference, there is a possibility that we can give a rewritable nature to Nb films by controlling the thickness of Nb₂O₅ layer. From the industrial point of view, it is preferable to give a rewritable nature to the color changeable Nb film since it may enable the Nb film to be used as new type of rewritable media such as color electronic paper. Therefore, the focus of this present work is to explore the possibility of these color Nb films as rewritable media. Our experimental data using a goniophotometer and a spectrophotometer suggest that our Nb films can be used as rewritable media by controlling preparation conditions.

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Electrochromism (EC) is known as reversible color change induced by electrochemical reaction. The cell using organic EC molecules is applicable to color electronic paper because the molecules represent various color by molecular design. Organic EC molecules based cell can improve coloration and bleaching properties to immobilize the molecules on the electrode, it is important for EC properties how to immobilize them. In this research, we prepared the EC cell that was consisted phthalate derivatives-modified siloxane film and nickel oxide film. The EC cells showed vivid magenta color from clear transparent state applying the voltage of -2.5V, indicating reduction of phthalate derivatives as EC materials. The EC cell using siloxane film showed quicker bleaching response and higher memory property than the solution based EC cell.

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The features of OCTA (Open Computational Tool for Advanced material technology) are explained. OCTA has been developed as a simulation engine platform and several types of simulation engines especially for polymeric materials have been implemented on OCTA. The self-consistent field (SCF) theory of polymers is also explained. This theory is implemented in one of OCTA' s simulation engine named SUSHI (simulation utilities for soft and hard interfaces). Deformations of a core shell type droplet on a wall are demonstrated with SUSHI. The wetting phenomena of the droplet on the wall are confirmed.

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Inkjet technology has been made a prominent development in printing letters and images.
This technology is, in essence, to quickly and precisely place functional fluid by droplet on designated positions based on digital data. In biotechnology field, various applications has been actively researched and developed, by utilizing digitally handling tiny volume of various Bio materials.
However, existing inkjet heads have many problems in handling Bio reagent which is totally different from conventional ink for printing. Therefore it is required to have dedicated purpose ink jet head for Bio.
Here in this publication, after clarifying those issues, various inkjet equipments with the inkjet heads for bio applications are introduced, as well as detailed descriptions on inkjet heads developed for bio applications.

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We have developed the latest inkjet head corresponding to 3D modeling printer. This head is positioned as successor head of GEN3 series head. It has inherited the applicability, high durability and high reliability to a wide range of ink. And, it was to improve the productivity and high-density nozzle. Furthermore, it has heater in the head. This made it possible to eject liquid droplets a high viscosity ink. In addition to this feature, we adopted a rigid structure to chamber of head. This improved droplet discharge rate per time, and realized variable drop size control by jetting successive droplets in very short time.

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The human has utilized microbes in a variety of uses including fermented foods, pharmaceutical products, a chemical products and an environmental sanitation. The microbes inhabit all over the world including the extreme environment that the human cannot live innumerably. In the present, we cannot utilize these microbes enough. The major problem in this issue is that a method to isolate an objective useful microbe from the innumerable microbes group is not fully established. In addition, we need to construct the microbial process suitable for these microbes to utilize for commercialization. In general, this process needs a long time until use of maximum ability of each microbe because of the individual characteristics. Therefore we developed three techniques, isolation of microbe, metabolite analysis and breeding of microbe to construct a microbial process more efficiently. Furthermore we advanced these elemental techniques to high-throughput ones.

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Several diseases such as neurodegenerative disorders, cancers, and lifestyle diseases represent typical diseases of aging society with fewer children in japan. These diseases cause the growth of medical spending. To obviate the risk of these diseases, rapid, high-sensitive, and cost effective medical diagnostics devices have been desired. However, conventional medical diagnostics devices have several disadvantages such as long assay time, sophisticated liquid handling procedure. To overcome these disadvantages, we have been developing and novel optical medical diagnostics devices based on “printable photonics technology”. Based on printable photonics technology, we could have achieved to develop the rapid, high-sensitive, and cost effective medical diagnostics devices.

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Over the past decade, we have been researching organic field-effect transistor (OFET) devices processed using various printable materials. One of the more important applications for the OFET devices is in sensors for use in healthcare. The use of these devices in wearable biosensors to detect biomarkers is recently attracting significant attention. In this article, we report on the fundamental detection mechanism and device structure for OFET-based biosensors with extended gate electrodes. We present the detection results in extended-gate OFET sensors for biomarkers that include immunoglobulin, glucose, nitrate and cysteine. Furthermore, OFET-based sensors applied to the monitoring of freshness in perishable foods and the detection of toxic heavy metal ions. Lastly, a potentially wearable flexible biosensor fabricated on a plastic film substrate using printing methods is demonstrated.

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The demand of sensor devices will increase to create the ambient sensing society. Printed electronics, flexible electronics and stretchable electronics are expected to realize that society. In our works, a printed, large sensing device for bed sensor and a stretchable, durable sensing device for shoes insole sensor were developed as applications of these technologies, with a focus on fields of health care and nursing care. In this paper, we introduce these developed devices and their technological and social background.

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Construction of three-dimensional (3D) tissues with pre-isolated cells is a promising achievement for novel medicine and drug-discovery research. Our laboratory constructs 3D tissues with an innovative and unique method for layering multiple cell sheets. Native animal tissues and organs have an abundance of capillaries to supply oxygen and nutrients, and to remove waste molecules. To construct even thicker 3D tissues by layering multiple cell sheets, it is critical to have medium or blood flow within the vascular networks of the cell sheets. Therefore, to perfuse medium in the cell sheet vascular network to maintain the viability of all cells, we developed two types of vascular beds. Such bioreactor systems, when combined with cell sheet engineering techniques, have produced functional vascularized 3D tissues. Here we explain and discuss the various processes to obtain vascular networks by properly connecting cell sheets and the engineering of 3D tissues.

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The demand of what is needed for printing technologies is moving on a moment-to-moment basis. However, there is almost no innovative changes for fabrication of the new commercial products like fuel battery and micro-chips for gene analysis. In the field of biochemistry, biomaterials such as nucleic acids are measured with DNA microarray constructed by photolithographic technique which is one of the printing technologies. But recently, the necessity of biomaterial detection with higher degree of accuracy appears in medical industry. In accordance with the request, a new technology, dubbed digital measurement, to detect biomaterials with highly quantity has been developed using tiny reaction loci prepared by photolithography, leading a new diagnostic technology. In this report, we present an example of digital analysis of gene and some problems to be solved for application of semiconductor processing technologies such as photolithography to detection of biomaterials.

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Point-of-care testing (POCT) has become an essential part of diagnostics in recent medical practice. To meet the growing demand for POCT especially in resource-limited settings, microfluidically patterned paper has been proposed as a platform for low-cost, yet practical (bio) chemical analysis, resulting in the development of so-called μPADs. Since their introduction in 2007, μPADs have drawn attention for their simplicity, allowing to perform complex procedures or multiple analyte sensing by a single sample introduction step. μPADs reported so far are reliant on various detection principles, including colorimetry, fluorometry, and electrochemical measurements. For developing μPADs, printing technologies, straightforwardly compatible with paper, have played an important role. In particular, inkjet printing is known as an exclusive fabrication technique enabling mass production and functionalization of μPADs. This review introduces fundamentals, fabrication, and several practical applications of inkjet-printed μPADs.

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Robotic Scrub Nurse (RSN) is a developing research and a challenging issue in the field of medical robotics. Audio processing, wearing-sensor and computer vision are applied to control the robot that could support surgeons during surgeries as an alternative of human nurse. On the other hand, surgeons wish that RSN should be able to decide the correct action by recognizing surgical situations autonomously just like skilled human nurses. In general, surgical situations can be discriminated by surgeons' hand actions during surgeries. This article introduces and explains the authors' computer vision based method for recognizing surgical hand actions of surgeons from video sequences.

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