Of the triphenylmethane indicators bromothymol blue, thymol blue, bromocresol green, phenolphthalein and thymolphthalein, and the azo-dye methyl red, only thymol blue showed a promising colour change from light tan (dry) to deep blue (dry) in the required pH range. Drawbacks to be overcome ...
brasilin, nitrazin yellow, hematoxylin, phenol red, neutral red, cresol red, m-cresol purple, brilliant Yellow, orange I, alpha -naphtolphthalein, thymol blue, p-xylenol blue, cresolphthalein, phenolphthalein, nile blue A (sulfate), alpha -naphtholbenzein, thymolphthalein or water blue. ...
brasilin, nitrazin yellow, hematoxylin, phenol red, neutral red, cresol red, m-cresol purple, brilliant Yellow, orange I, alpha -naphtolphthalein, thymol blue, p-xylenol blue, cresolphthalein, phenolphthalein, nile blue A (sulfate), alpha -naphtholbenzein, thymolphthalein or water blue. ...