PURPOSE: To obtain a simple, quick means, by which the concentration range of bromine ions in a developer is detected simply and positively and the activity of the developer is kept at a correct level, by making pH of a solution including bromic ions and the main component of silver halide developer to be acidic, and comparing developing properties of the silver halides in liquids to be checked of two levels having different concentrations.
CONSTITUTION: The lower limit of the concentration range of allowable bromide ions is expressed by Br-DL, and the upper limit is expressed by Br-DU. A specified amount VD of the developer with the bromine ion concentration Br-D is picked up. An Ag+ liquid equivalent to the amount of the bromine ions such as Br-DL×VD and Br-DU×VD is added to the developer. Liquids to be measured SDL, SDU, and the like are prepared in correspondence with the picked up developer. When the Br-D is in the range of Br-D<Br-DL, the concentration of the Ag+ in the SDL and SDU are both excessive, and silver bromide in the SDL and SDU is developed and blackened. In the case of Br-DL≤Br-D≤Br-DU, the Br- in the SDL is excessive, the Ag+ in the SDU is excessive, and only the SDU is blackened. In the case of Br-DU<Br-D, the Br- in the SDL and SDU are both excessive, and not blackened. Therefore, by comparing the behaviors of the liquids to be checked, whether the Br-D is absent or present in the allowable concentration range of bromine ions regarding developing activity or exceeds the range is judged.
KOBAYASHI KAZUHIRO
KOBOSHI SHIGEHARU
