Question: what is ptd in hair color?
Answer: What is PPD/PTD? PPD (p-Phenylenediamine) and the structurally-related 1,4-toluenediamine (PTD) is an organic compound used in over 99% of all permanent hair dyes, as well as in a variety of other sources such as some Henna Tattoos, Semi-permanent makeup and even black clothing.