| 摘要 |
PURPOSE:To obtain an inexpensive and safe oxygen detecting agent easy to handle and capable of detecting even low concn. oxygen in an atmosphere, by blending at least one compound selected from a group consisting of a phosphite or a hypophosphite and redox coloring matter. CONSTITUTION:As a phosphite or a hypophosphite constituting an oxygen detecting agent, there is an alkali metal salt or alkaline earth metal salt of phosphorous acid or hypophosphorous acid and a sodium salt is preferred. As an especially pref. compound, sodium phoshite is designated. In addition, these metal salts are used even in a hydride form having water of crystallization without any hindrance. The redox coloring matter being the other one component is coloring matter showing different colors by an oxidized state or a reduced state and, for example, Meldola's blue is represented. In a blending ratio, there is not limit even if the compounding amount of the redox coloring matter is one capable of developing function as the oxygen detecting agent but said coloring matter is usually compounded in an amount of 0.001-13wt%, pref., 0.01-5wt% on the basis of the sum amount of at least one compound selected from the group consisting of the phosphite and hypophosphite and the redox coloring matter. |
