
General Description:
Ammonium Thioglycolate is a colorless to pale yellow liquid with a distinct, sulfur-like odor. It is the ammonium salt of thioglycolic acid and functions primarily as a reducing agent. Known for breaking disulfide bonds in keratin, it is widely used in hair restructuring applications. Its chemical action is reversible, allowing it to reshape hair fibers when neutralized.
Uses in the Cosmetic Industry:
Used to break and reform disulfide bonds in hair, allowing the hair to be restructured into curls or waves.
Used to chemically relax curly or frizzy hair by breaking keratin bonds and straightening hair fibers.
Occasionally used in formulations for chemical hair removal due to its ability to weaken hair structure.
Found in salon-grade treatments designed to modify hair texture temporarily or semi-permanently.
Hazards:
Can cause moderate to severe irritation to the skin, eyes, and respiratory tract. Protective measures must be taken during formulation and application.
At high concentrations or prolonged exposure, it can damage skin or mucous membranes.
Harmful if swallowed—strictly for external use only in regulated concentrations.
Strong sulfur-like odor may be unpleasant or irritating to some users.
Use is subject to strict concentration limits in most jurisdictions. For example, the EU Cosmetic Regulation allows up to 8% in ready-for-use hair waving products and 11% in depilatories, with required safety warnings and pH control.
CAS Number: 5421-46-5
INCI Name: Ammonium Thioglycolat.
Composition: Ammonium salt of thioglycolic acid
Typically supplied as an aqueous solution (with 40–60% water)
Active component: HSCHâ‚‚COONHâ‚„
Purity Grade: Cosmetic Grade / Technical Grade
Standard purity of ≥98% (as active content, depending on supplier)
Often sold as a 50% aqueous solution
Appearance: Clear, colorless to pale yellow liquid
Characteristic sulfurous odor
Solubility: Fully soluble in water
Not soluble in oils or non-polar solvents
Preservation: Does not require added preservatives
Stable under controlled pH and temperature
Antioxidants may be used to enhance stability in complex formulations
Storage: Store in a cool, dry, well-ventilated area
Keep in tightly sealed containers, away from heat, light, and incompatible substances (e.g., oxidizers)
Recommended temperature: 5–25°C
Protect from air and moisture to prevent oxidation
Raw Material Sources: Derived synthetically from:
Thioglycolic acid (typically synthesized from chloroacetic acid and sodium hydrogen sulfide)
Neutralized with ammonium hydroxide
Manufacture: Thioglycolic acid is synthesized from a base reaction of chloroacetic acid and hydrogen sulfide.
It is then neutralized with ammonium hydroxide to form Ammonium Thioglycolate.
The solution is filtered, pH-adjusted, and stabilized for cosmetic use.
Animal Testing: Not tested on animals by ethical suppliers
May be eligible for cruelty-free certification if sourced accordingly
GMO: Non-GMO — not derived from genetically modified organisms
No biotechnological processes involved in its manufacture
Vegan: Yes – synthetic and contains no animal-derived ingredients
Suitable for vegan formulations
Warning: For external use only
May cause skin and eye irritation
Can release toxic gases (hydrogen sulfide) if mixed improperly
Wear gloves and eye protection when handling in concentrated form
Avoid inhalation of vapors; use adequate ventilation in manufacturing
Keep out of reach of children
pH must be carefully controlled in final formulation (typically 7.0–9.5)
THE STORY OF AMMONIUM THIOGLYCOLATE
Ammonium Thioglycolate: The Precision Bond-Breaking Agent
Ammonium Thioglycolate is a key active ingredient used in professional hair reshaping systems, including permanent waving, straightening, and relaxing creams. It works by breaking disulfide bonds within hair keratin, allowing irreversible restructuring of curl pattern, texture, and shape.
High-Purity Synthesis for Controlled Reactivity
Produced by neutralizing thioglycolic acid with ammonium hydroxide, Ammonium Thioglycolate is supplied as a stabilized, cosmetic-grade aqueous solution. Each batch is filtered, pH-adjusted, and quality-tested to ensure predictable bond-breaking strength, low odor, and long-term storage stability.
Reshape. Reform. Redefine
Primary functions of Ammonium Thioglycolate in cosmetics:
✅ Breaks disulfide (–S–S–) bonds in keratin
âś… Enables permanent waving, curling, or straightening
✅ Works efficiently under alkaline pH (8–10)
âś… Compatible with creams, gels, and lotion formats
âś… Allows controlled processing time for salon professionals
Used in: perm lotions, Brazilian straightening systems, texture-softening formulas, and chemical hair relaxing.
Powerful Chemistry. Strict Handling. Professional Use Only
Typical use level: 5–15% active in hair perming systems.
Must be handled with gloves and eye protection.
Store in airtight containers away from heat, metal ions, and oxidizers.
Requires secondary neutralizer in final formulation (commonly hydrogen peroxide or sodium bromate).
Complies with global cosmetic regulatory limits when used in professional-only formulations.
Formulator’s Queries, We Answered
1. What is Ammonium Thioglycolate used for in cosmetics?
Ammonium Thioglycolate** is a key active ingredient used in hair perming (permanent wave systems) and chemical hair relaxers. It breaks disulfide bonds in hair keratin, allowing hair to be reshaped into curls or straightened, depending on the application.
2. What is the CAS number and INCI name of Ammonium Thioglycolate?
CAS Number: 5421-46-5
INCI Name: Ammonium Thioglycolate
3. Is Ammonium Thioglycolate safe for use in personal care products?
Yes, when used at controlled concentrations and pH levels, it is considered safe and effective for use in professional hair treatments. It must be used according to cosmetic regulatory guidelines, and neutralizers are typically applied afterward to rebalance pH and prevent damage.
4. Is Ammonium Thioglycolate natural or synthetic?
Ammonium Thioglycolate is a synthetic chemical compound made by neutralizing thioglycolic acid with ammonium hydroxide. It is not derived from natural sources.
5. Can Ammonium Thioglycolate cause skin or eye irritation?
Yes, in its concentrated form, it can cause irritation to the skin, eyes, and respiratory system. Personal protective equipment (PPE) should be used during handling, and it should only be applied by trained professionals in controlled settings.
6. Is Ammonium Thioglycolate vegan and cruelty-free?
Yes. It contains no animal-derived ingredients and is considered vegan. It can be cruelty-free depending on the supplier’s policies and certifications regarding animal testing.
7. What kind of products typically contain Ammonium Thioglycolate?
You can find Ammonium Thioglycolate in:
Hair perming systems
Chemical hair relaxers
Keratin softening treatments
Some depilatory (hair removal) creams
8. How should Ammonium Thioglycolate be stored?
It should be stored in tightly closed containers, in a cool, dry, and well-ventilated area, away from heat and oxidizing agents. Avoid exposure to direct sunlight or air, as the ingredient can degrade when oxidized.
9. What precautions should be taken when using Ammonium Thioglycolate in formulations?
Use in well-ventilated areas
Avoid mixing with strong acids or oxidizers
Apply a neutralizer post-treatment to stop the chemical action
Follow local cosmetic safety regulations for concentration limits
10. Is Ammonium Thioglycolate listed under California Proposition 65?
No, Ammonium Thioglycolate is not currently listed under California Proposition 65 for carcinogenicity or reproductive toxicity when used within regulatory limits.