If you find that you are having more bad hair days than good ones, then perhaps you should take a look at how much hair dye you are using. Recent studies have shown that dyeing your hair can increase the chance of having bad hair days. Apparently, even after only two dyeing sessions, hair can be damaged to the point where the structure is changed. It is the chemicals that are used to bleach and colour hair that cause the oily layer that coats each strand to be stripped away. Microscopic analysis of hair revealed that once hair has been dyed or bleached, the individual hairs become electrically charged and this reduces their ability to shed water, meaning the hair becomes difficult to manage.
Proctor & Gamble, who lead the study, used high-powered microscopes to study the changes that chemicals can cause to the structure of your hair. The principal scientist at P&G’s London Innovation Centre, Dr Frauke Neuser, said that they found hair became highly charged even after one or two applications of hair dye. She stated that, “Hair that has never been coloured has a protective layer that waterproofs hair. It is the same sort of layer that allows dogs to shake themselves dry after they have been swimming for example. When we colour our hair or bleach it, the chemical reaction removes this layer almost completely after one or two colourings. Hair cannot regrow this layer once it is gone without growing new hair. The hair becomes very highly negatively charged and it sticks together when wet – it changes the way the hair behaves. It is difficult to comb and feels more like straw.”
The technology that was used to test the hair is called atomic force microscopy, and scientists based at P&G’s laboratories used this method to study the changes that hair undergoes when it is coloured. It was discovered that the peroxide and ammonia that is contained in most hair dye products stripped off the oily layer, known as lipids, on the outside of the hair. This left the hair electrically charged meaning it would clump together when wet and can fly-away and more full of static when dry. It was also found that the normal shampoo and conditioner products that were specifically designed for coloured hair, failed to repair the damage to the hair as the chemicals they contained, such as silicon, could not stick to the negatively charged hair.
Dr Neuser says, “Most of the products just get washed straight down the drain and have little effect on the hair.” There may be a solution to the damage that is caused by dyeing hair however, as scientists at P&G believe they have found an answer to the problem. In research that has been published in the International Journal of Cosmetic Science and New Scientist, they have shown that it is possible to produce liquid crystals that will stick to the hair that has been negatively charged. These liquid crystals, which are made from a chemical that has been used in waste water treatment, together with detergent like molecules, stick to the coloured hair. Luckily, for all us ladies who suffer from bad hair days, this ingredient is being used in a new range of shampoos and conditioners manufactured by Pantene.