| 摘要 |
PURPOSE:To enable a color developing solution to be preserved stable for a long term not accompanied by deterioration of characteristics by preserving the color developing solution containing a color developing agent, a specified preservative, and an alkali agent in a receptacle made of a plastic package material specified in oxygen permeability coefficient. CONSTITUTION:The color developing solution contains the color developing agent made of an aromatic primary amine, the preservative made of alkylated hydroxylamine represented by the formula shown on the right (each of R<1> and R<2> is H or 1-3C nonsubstituted alkyl, and either of them is said alkyl), and the alkali agent for keeping the color developing solution in a pH of >=9.5. This solution is preserved in the receptacle made of the plastic packaging material having an oxygen permeability coefficient of <=50ml/m<2>.atm.day at a temperature of 20 deg.C and in a relative humidity of 65%, and as the receptacle, flexible pillow type ones are preferable from the viewpoint of compactness and easiness in handling. Such a receptacle 10 is obtained, for example, by sticking and fixing a pair of outside walls 21, 22 each made of a flexible rectangular sheet to each other so as to overlap each other at each outer border. |
