Question: How does colour transfer when we use dye?

Sam Geen answered on 24 Jun 2013:

Dye is made of coloured particles that stick to what we’re trying to die (often using a different chemical to help it stick). There are various ways to make it stick – for example, acid dyes stick because an acid is positive hydrogen ions and negatively charged ions in a solution, and these charges help it stick. Other methods work with alkilis (the chemical opposite of acid). Sometimes it depends on the material – the fibres in paper are better at absorbing ink than a plastic surface, say.

There are many reasons things are different colours – for example, sulphur is yellow and can be used to make yellow dies. Certain berries are red or purple, etc. People have used natural dies for a long time (i.e. from things found in nature), but recently people have started making synthetic chemicals as dyes.