Anovel intrinsic photosensitive polyimide containing a diazo group in the main chain was prepared,and the quantum yield for the photocrosslinking reaction was determined to be 0.13 under air at room temperature by GPC measurement. The quantum yield for the photo-decomposition reaction of the diazo group was also determined to be 0.06. These values are higher by about two orders of magnitude than those for the photocrosslinking reaction of a benzophenone-containing polyimide, which is prepared from benzophenonetetracarboxylic dianhydride (BTDA) and methylene bis(2-ethylaniline) (DEDPM).The reaction was found to proceed via its singlet excited state to give a long-lived active intermediate,a carbene, which plays a great role in the increase in the photoreactivity. Characteristics of the photoreaction and the fluorescence behavior of a series of imide-substituted diphenyldiazomethanes were also investigated, showing that the reactivity of the diazo groups is not affected by the existence of charge transfer structures of the imide groups.

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