| Abstract: | For the purpose of obtaining a water-soluble, reciprocity-law-failing photoresist, a study was made on the photo-crosslinking properties of various systems composed of water-soluble polymers and bisazides. Reciprocity-law-failing photoresists are suitable for use in the fabrication of black matrix color picture tubes without any alteration in the shadow mask. As a result, a system containing polyvinylpyrrolidone, polyacrylamide, and 4, 4′-diazidostilbene-2, 2′-disulfonic acid disodium salt was found to show a significant reciprocity-law-failing property in the range of light intensity used practically in black matrix fabrication. The mechanism of the photo-cresslinking reaction of this photoresist was investigated. It is suggested that the bisazide decomposes to liberate a reactive dinitrene intermediate. This photodecomposition was found to proceed reciprocally. The nitrene reacts with polymer molecules to form a water-insoluble three dimensional network. If, however, oxygen is present, this crosslinking reaction is inhibited by a preferential reaction between dinitrene and oxygen. By this oxygen effect, this photoresist reveals significant reciprocity-law-failing characteristics. |
