Hair is primarily bleached using chemicals such as hydrogen peroxide and persulfate salts, which are the most common agents found in commercial hair lighteners.
Common Hair Bleaching Chemicals
The process of bleaching hair involves chemicals that lighten its natural pigment. The most widely used substances in modern commercial hair bleaching products are:
- Hydrogen Peroxide: This is the foundational chemical in most hair bleaches. It works by oxidizing the melanin (pigment) in the hair, making it colorless.
- Persulfate Salts: Often used in conjunction with hydrogen peroxide, persulfate salts (like ammonium, potassium, and sodium persulfate) act as boosters, accelerating the bleaching process and enhancing its effectiveness.
Historical Bleaching Agents
Throughout history, various other chemicals were employed to lighten hair, though many are no longer used due to their harshness or less predictable results:
- Sulfuric Acid: Historically, this strong acid was sometimes used, but it is extremely corrosive and damaging.
- Wood Ash: An alkaline substance, wood ash could provide some lightening effects due to its chemical composition.
- Lye: Also known as sodium hydroxide, lye is a highly alkaline substance capable of bleaching, but it is very caustic and dangerous for hair and scalp.
- Hypochlorite Bleach: More commonly known as household bleach, hypochlorite was used, but it is very damaging to hair and can leave it brittle or discolored.
Unintentional Hair Bleaching
It's also worth noting that hair can be bleached unintentionally through natural means. Prolonged exposure to sunlight, for instance, can gradually lighten hair over time, though this is a physical process rather than a direct chemical application.
To summarize the key chemicals used for bleaching hair:
| Category | Chemical Agent | Description |
|---|---|---|
| Common/Current | Hydrogen Peroxide | Primary oxidizing agent used in modern commercial bleaches. |
| Common/Current | Persulfate Salts | Boosters (e.g., ammonium, potassium, sodium) to enhance bleaching. |
| Historical | Sulfuric Acid | A highly corrosive acid, no longer used for hair. |
| Historical | Wood Ash | Alkaline substance used in ancient times. |
| Historical | Lye (Sodium Hydroxide) | Caustic alkaline substance, very damaging to hair. |
| Historical | Hypochlorite Bleach | Household bleach, extremely harsh and damaging for hair. |
