Which colors coat only the surface of the cuticle and do not enter the cortex?

• A. Semi-permanent
• B. Long-lasting permanent
• C. Permanent
• D. Temporary

Answer: (D)

Colors that stay on the outermost layer of the hair—the cuticle—are surface coatings. Temporary color works this way: pigment molecules adhere to the scales of the cuticle without breaking open the cortex, so there is no penetration into the inner structure. Because no chemical processing opens the cuticle to let pigment into the cortex, these colors wash out quickly with shampoo, giving a reversible, non-permanent change. This is why temporary color is the best match for coating the surface only.

In contrast, colors described as long-lasting or permanent rely on chemical processes that lift or open the cuticle and deposit pigment inside the cortex, creating longer-lasting results. Demi-permanent or semi-permanent colors tend to involve some level of uptake beyond the surface, which is why they don’t fit the “surface only” idea as neatly as temporary color.