What is temporary color? How long does it last?

Temporary hair color does not penetrate the cortex or the hair. Instead, it coats the outside of the hair shaft with color that washes out in one or two shampoos. Although there is no chemical reaction, if hair is damaged and porous, the color can penetrate and stain the hair. Temporary color is great for last-minute touch-ups before a big party or to "make do" between appointments with your stylist.