Hydrogen is considered a potential future energy source. Among other applications of hydrogen, hydrogen-rich water is emerging as a new health care product in industrial areas. Water electrolysis is typically used to generate a hydrogen rich water system. We annealed 10AA carbon paper in air to use it as an electrode of a hydrogen rich water generator. Driven by annealing, structural changes of the carbon paper were identified by secondary electron microscope analysis. Depending on the various annealing temperatures, changes of the hydrophilic characteristics were demonstrated. The crystal structures of pristine and heat-treated carbon paper were characterized by X-ray diffraction. Improvement of the efficiency of the electrochemical oxygen evolution reaction was measured via linear voltammetry. The optimized annealing temperature of 10AA carbon paper showed the possibility of using this material as an effective hydrogen rich water generator.

The purpose of this study is to examine the exposure risk of thermal paper ingredients by analyzing skin permeation using an in vitro Franz cell. Thermal printer papers are usually used for receipt papers, and the skin of shop assistant is continuously exposed to hazardous ingredients of thermal papers. The skin permeation risk of thermal paper ingredients, including bisphenol A and toluene, was determined using an in vitro Franz diffusion cell method using hairless mouse full skin and human cadaver epidermis. Bisphenol A, a major component in each thermal paper, showed moderate skin penetration. Most skin absorption rates were similar in both hairless mouse full skin and human cadaver epidermis. The possible risk of exposure to toxic substances in thermal paper was confirmed from this study. These is results are expected to contribute to establishment of management regulations for thermal papers.