Victoria blue R is a dye of the triarylmethane class with formula C<sub>29</sub>H<sub>32</sub>N<sub>3</sub>Cl. It has a blue colour that changes to yellow at pH values below 1.
Fastness
The dye exerts a high light fastness and washing fastness.
UV/VIS absorption
Victoria Blue R has an absorption peak of around 610 nm.