Fabrication of the Black Matrix Color Picture Tubes by Using Photoresist with Significant Reciprocity-law-failure

Abstract

For the purpose of producing the black matrix picture tubes having the matrix apertures smaller than those of the shadow mask, a photolithographic optical method involving the control of exposure conditions and without affecting the shadow mask apertures is developed.
It is pointed out that the use of a reciprocity-law-failing photoresist whose photosensitivity decreases rapidly with the decrease of light intensity is indispensable to avoid the deformation of the black matrix holes caused by the overlapping of the projected images formed by the photographic exposures.
After studying various systems composed of water-soluble polymers and bisazides, a system showing a significant property of reciprocity-law-failure is found and a suitable condition for the optical method is attained.