| abstract |
PURPOSE: To reduce cost of a toy and make its operation easy by mixing a dye such as phenolphthalein which colors when alkalified and is decolored by reduction of pH with an alkaline substance. n CONSTITUTION: The composition for water soluble toy is prepared by mixing a powder dye with features of developing a given color on a given alkaline pH and becoming colorless on reduction of pH comprising phthalein type dyes such as phenolphtalein, thymolphtalein, o-cresolphthalein and so on, p- nitrophenol, and so forth, with an alkaline substance. The composition is preferably to be mixed with a developing agent to make its color more brilliant on dissolving it into water and a filler. And, the alkaline substance to be mixed with the composition comprises sodium carbonate, potassium hydrogenphosphate, potassium polyphosphate and so forth. n COPYRIGHT: (C)1989,JPO |