Permanent – semi permanent colouring.
Sometimes we have to explain why we use semi permanent colouring instead of permanent at the hair ends, what is the difference between them, and why it lasts the same or even more than the permanent.
Firstly, we have to examine the function of colouring.
The ammonia or its substitute of the permanent colouring opens the hair cuticles, so that the main colouring ingredients (peroxide of hydrogen and pigments) penetrate hair. The peroxide of hydrogendisintegrates the natural pigments of hair (melanin), whilst the artificial ones are too small and penetrate the open hair cuticles. Due to the compound with the other colouring elements, they multiply their size, so that they cannot get out of hair. That’s how we succeed the permanent colour on our hair.
The semi permanent colouring, instead of permanent, does not follow this process because it does not include ammonia or any substitute. The pigments of the semi permanent colouring don’t penetrate hair, but stick on and between its cuticles. Hair washing removes them slowly and hair returns to its natural colour after a while. Don’t panic! Rain is not a problem! It’s very impressive how much it lasts.
Why do we use semi permanent colouring at hair ends?
The permanent colouring means that we have to open and close the hair cuticles, which make them break. Also the peroxide of hydrogen affects hair’s structure and health; the ends fade and the colour lasts only a few washes or it looks heavy because of the big amount of pigments.
The semi permanent colouring does not cause these problems, as it does not have to penetrate and damage hair. Due to its overlapping advantage, it avoids damage and offers impressive colours and healthy hair.