The Colour of Dye Solutions

Abstract

IT is generally accepted that the colour of dye solutions depends upon the chemical structure of the dye, and colour changes are usually attributed to some change in constitution; but certain recent investigations on colloidal solutions show that this argument must be accepted with caution. It is well known that colloidal solutions of the metals are highly coloured. Further, it is recognised that many dyes exist in solution in what, for lack, of a better term, must be called the colloidal state. Some observations of my own point to the following statement as being true for certain dyes:—