Amid an industry-wide ban of toxic foaming agents such as HCFC, this book examines the fundamental properties, principles, and applications of foaming technology using environmentally neutral carbon dioxide and nitrogen agents. While Japan is considered a pioneer in this field, documentation and exposure is often hampered by language difficulties. Japan's foremost researchers provide invaluable insight to their most cutting-edge research and applications, including microcellular technologies and recently developed foaming resins. Enhanced by real-world examples and images throughout, the book describes foaming phenomena, polymer-CO2/N2 system properties, and mathematical models used to predict and estimate changes in these properties.