Abstract: The apparatus for treating surface of boards includes treating means for treating surface of boards by supplying sequentially a treating solution and a rinse liquid on boards placed on a treating table; solution collecting means for collecting waste treating solution separately from waste rinse liquid; waste solution storing, concentrating detecting and solution supplementing means for storing the waste treating solution, detecting the concentration of at least one ingredient in the waste treating solution by an electric conductivity meter and/or an absorption photometer, supplementing treating solution for adjusting containing necessary ingredients depending on the detected value, and adjusting the treating solution; and treating solution feed means for feeding the adjusted treating solution into the treating means. By thus constructing, the treating solution can be recycled, and if recycling is repeated, the performance of the treating solution itself can be maintained.

Abstract: In a semiconductor manufacturing process or a liquid crystal board manufacturing process, a resist stripping solution blending an organic alkali and an organic solvent is used for stripping the resist completely from the board. An apparatus for controlling this resist stripping solution comprises a resist stripping solution discharge device for discharging the resist stripping solution by detecting the dissolved resist concentration in the resist stripping solution by using an absorption photometer, a source solution and water replenishing device for replenishing the resist stripping source solution and pure water by detecting the liquid level of the resist stripping solution by a liquid level gauge, and a source solution and/or water replenishing device for replenishing at least one of the resist stripping source solution pure water by detecting the water concentration of the resist stripping solution by using an another absorption photometer.

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.