Phthalein dye

Chemical structure of phenolphthalein, a common 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

  • Triarylmethane dye

References

  1. ^ Sabnis, Ram W. (2010). "Phthalein Dyes". Kirk-Othmer Encyclopedia of Chemical Technology. doi:10.1002/0471238961.phthsabn.a01. ISBN 978-0471238966.


  • v
  • t
  • e