Sixth Formers have been synthesising their own permanent dyes during a chemistry project in which they have studied the chemistry of colour and how chemists have a fundamental role in the restoration of old paintings. The students made a series of azo dyes, which are permanent and typically found in food colouring, paint and printer ink.
They started with two frozen amine compounds which they brought to room temperature before combining. The chemical reaction produced a colour in the red and orange spectrum.
Teacher Mrs Hearne said: ‘The Year 13 students have been learning about the history of colour and we have been linking it to chemistry in the art gallery so they have been studying all the aspects involved in painting. For example if you are restoring an old painting there is chemistry involved in getting the pigments exact. You have also got to get the binding medium exact to achieve the right paint consistency.
They are using amines which are aromatic compounds so they all have benzene rings. The rings link together in the chemical reaction and that is what creates the colour. We have had synthetic dyes since the 1800s when William Perkins accidentally discovered how to make a purple dye, he called mauve, when he was trying to make the drug quinine, a cure for malaria.
‘Everything the students are doing is linked into the content of their exams but these students are following the Salters chemistry course in which Chemical concepts are introduced within a relevant context. They would learn about benzene chemistry in every A Level course but the difference with this is that it is put into a real life situation with a practical application.’