Organic light-emitting diodes have many advantages including self-emission, thinness and light weight, and they have been the subject of much interest for next-generation display technology. Light-emitting polymers are expected to be particularly suitable for printing processes which are essential for the cost-effective production of large-sized panels. In this paper, the material design for higher efficiency and longer lifetime, and the latest progress in polymer organic light-emitting diodes (PLEDs) are discussed.
(by Nobuhiko AKINO, Yoshiaki TSUBATA, Takeshi YAMADA)

Induced pluripotent stem cells (iPSC) can differentiate into a large variety of cells in the body. iPSC is expected to be applied in the field of regenerative medicine. Sumitomo Dainippon Pharma Co., Ltd. is now developing some iPSC derived cellular therapeutic products for treatment of nervous system and eye diseases. In this article, we report on the establishment of iPSC using Sendai virus vectors and on the construction of cell banks for clinical use under GMP compliance.
(by Hidetaka OHARA, Satoshi ANDO, Akiyoshi KISHINO)

In recent years, demand has been increasing for rubber products having rubber elasticity in a low temperature range, that is, excellent cold resistance. In order to improve the cold resistance of rubber products, it is extremely important to improve the cold resistance of the main component, synthetic rubber. We have developed novel ESPRENE® EPDMs that have excellent cold resistance which is greater than conventional EPDMs by controlling composition distribution and copolymerizability with our proprietary technology. In this paper, we introduce the development of EPDMs with excellent cold resistance.
(by Kenta WATANABE, Sadayuki NAKANO)

The STRONTEC® KA · KO · I is an insecticidal device to provide an excellent mosquito repellency in outdoor spaces. It is the first and innovative product in Japan to be approved to quasi-drug as a pest control device using ultrasonic atomization. The device has a compact and easy-to-carry design which is suitable for mosquito repellent product for outdoor spaces. It delivers the active ingredient, Eminence® by periodical atomization process to produce solid and sustained special repellency. This paper introduces the STRONTEC® KA · KO · I repellent device by presenting its successful history of Research & Development as well as the product performances.
(by Tomohiro KAJIHARA, Hiroshi OKAMOTO)

In this paper, we first review various fabrication technologies for GaN single-crystal wafers which have been reported to date. Then, our original fabrication technique for GaN single-crystal wafers called void-assisted separation (VAS)-method is introduced. Our recent progresses in GaN wafer fabrication technology for nextgeneration devices, such as further improvement of GaN crystal quality as well as increasing wafer size, are also explained in detail.
(by Hajime FUJIKURA, Toshihisa INOUE, Toshio KITAMURA, Taichiro KONNO, Takayuki SUZUKI, Tetsuji FUJIMOTO, Takehiro YOSHIDA, Masatomo SHIBATA, Toshiya SAITO)

An electrostatic discharge is one of the most concerning ignition sources for combustible substances. In order to carry out appropriate safety measures to prevent from ignition, it is necessary to understand correct fundamental phenomena of charging and discharging and to master the technology by considerable training. And next step, application of a risk assessment technology of static electricity is desired. Sumitomo Chemical Co., Ltd. has developed one of these technologies. This paper introduces one practical case study from it.
(by Kiyoshi OTA)

Most chemical processes contain at least two of the three phases of solid, liquid and gas. Therefore it is essential to fully understand phase equilibria for the logical design of processes and apparatus. The basic theory of phase equilibrium has already been established, but there are some exceptions which are not compliant with the theory. Many of those are influenced by chemical reactions within a certain phase or between different phases, so consideration of the reaction is necessary for precise reproduction of such unusual behavior. In this paper, some models for phase equilibria in reactive mixtures and several examples of their application in industrial plants are presented.
(by Tetsuya SUZUTA)