Phthalein dye

Phthalein dyes are a class of dyes mainly used as pH indicators, due to their ability to change colors depending on pH.[1] They are formed by the reaction of phthalic anhydride with various phenols. They are a subclass of triarylmethane dyes.
Common phthalein dyes include:
- Bromothymol blue
 - Bromocresol green
 - Bromocresol purple
 - Cresol Red
 - o-Cresolphthalein
 - Chlorophenol red
 - Dixylenolphthalein
 - Guaiacolphthalein
 - α-Naphtholphthalein
 - Phenolphthalein
 - Phenolsulfonphthalein
 - Tetrabromophenolphthalein
 - Thymol blue
 - Thymolphthalein
 - Xylenolphthalein
 
See also
References
- ^ Sabnis, Ram W. (2010). "Phthalein Dyes". Kirk-Othmer Encyclopedia of Chemical Technology. doi:10.1002/0471238961.phthsabn.a01. ISBN 978-0471238966.