What are the precautions for dyeing hair?

1, hair dyeing in foggy days. It is best to dye your hair when the air quality is good, because the hair dye that penetrates into the scalp will react with tobacco, smoke, etc., and produce toxic substances.

2. The hair color should not be too dark or too bright. In general, the content of p-phenylenediamine in dark or light hair dyes is high. If you don't want the hair dye to hurt your hair mercilessly, give up dark hair dyeing!

3. Hair dyeing and perm are out of sync. Perm is very convenient after dyeing, but most of the potions used for perming contain alkaline components and oxidants, which will destroy the surface layer of hair, make the internal structure of hair unprotected and make hair more fragile.

4. Some bobbins are not suitable for dyeing hair. MM during pregnancy and lactation can't dye her hair; The bobbin with damaged scalp can't dye hair; People with a family history of cancer are not suitable for dyeing their hair; People who are old and weak and in kidney is not good can't dye their hair.