Provided are a color display driving principle obtained while taking into account a difference in eye sensitivity to the flickering of differently colored lights, a TFT liquid crystal display module structure that is adequate for this method, and a double-panel projection type display device. The present invention provides novel intermediates like 4,6-dihydroxy-5-2,2\u2032bipyrimidine of formula and N-2,2\u2032-bipyrimidinyl-4-t-butyl benzenesulfonamide cesium salt and process for preparation thereof. The present invention comprises the step of maintaining the level height of the treatment solution in the storage portion at a predetermined height by supplying the treatment solution to the storage portion by the said another pump.