抄録
Every summer, spontaneous ignition of celluloid and film is reported in Tokyo. The majority of these cellulose nitrate plastics are thin, colourless and transparent sheets in the advanced stage of decomposition.
Self-ignition of celluloid and film is dependent upon many factors. Atmospheric temperature is one of them. The higher the temperature is, the more decomposition of celluloid and film progresses.
Everyday temperature (highest and lowest) during the months of May, June, July, August, September and atmospheric temperature per hour in 1949, 1950 and 1951 is plotted in figures, According to these figures, when the highest temperature during 48 hours before outbreak of fire are 30°C or more, celluloid is easy to self-ignite and they rises on step by step in whole.
