| 摘要 |
PURPOSE:To enable an easy identification of production time simply by dissolving a part of a powder chemical in water or other liquids with the addition of at least one kind of water soluble coloring agent from among a synthetic dye, an inorganic pigment, an organic pigment and a pH indicator. CONSTITUTION:Available for a water soluble coloring agent to be added for identifying production time is a synthetic dye, an inorganic pigment or a pH indicator. The synthtic dye referred here includes an azoic dye and the like and the inorganic pigment, ultramarine, guinea green and the like. In addition, the oranic pigment include an unsoluble azo compound, a soluble compound, a dye lake and the pH indicator, methyl orange, methyl red, tymol blue and the like. At least one kind from among said coloring agents is added to an extinguishing agent. In the use of the agents, thet are color coded according to production years and grouped as one cycle at an interval of 5-10 years. This operation is repeated in sequence to mix the extinguishing agent with the coloring agents presenting colors of production year. |
