Abstract: A resist stripping solution is used in the stripping of resist in a liquid crystal board manufacturing process or semiconductor manufacturing process. The apparatus for controlling the resist stripping solution comprises a resist stripping solution discharge device for discharging resist stripping solution by detecting the dissolved resist concentration in the resist stripping solution using an absorption photometer, first replenishing device for replenishing organic solvent and alkanolamine such as MEA or the like by detecting the liquid level of the resist stripping solution using a liquid level gauge, and second replenishing device for replenishing at least one of organic solvent and alkanolamine such as MEA or the like by detecting the concentration of alkanolamine such as MEA or the like of the resist stripping solution by an absorption photometer.

Abstract: A photoresist stripping liquid composition comprising an alkanol amine compound, a sulfone compound or sulfoxide compound, and a hydroxy compound. The composition is excellent in its photoresist stripping performance, safety and working efficiency, and does not cause corrosion on a substrate possessing a metal film.

Abstract: An alkaline developing solution is used in development of photosensitive organic resin (photoresist) in liquid crystal board manufacturing process or printed board manufacturing process. The apparatus for controlling developing solution comprises developing solution discharge device for discharging developing solution by detecting the dissolved resin concentration in the developing solution by means of an absorption photometer (16), first replenishing device for replenishing undiluted developing solution and pure water by detecting the liquid level of the developing solution by means of a liquid level gauge (3), and second replenishing device for replenishing undiluted developing solution or pure water by detecting the alkali concentration of the developing solution by an electric conductivity meter (15). By thus constituting, the developing performance of the developing solution may be always kept constant, and the operation down time may be notably shortened.