At a glance
- CAS number
- 1310-73-2
- INCI name
- Sodium Hydroxide
- Function
- ph_adjuster, denaturant, saponifying agent
- Typical use level
- 0.01%–5%
- Solubility
- water
CAS number and synonyms are sourced from PubChem. Function, usage levels, pH and compatibility are AI-assisted formulation guidance — verify against your supplier's technical data sheet and applicable regulations before use.
Also known as
Caustic soda Sodium hydrate Aetznatron Soda lye White caustic Soda, caustic Natriumhydroxid Rohrputz Plung Collo-Grillrein Collo-Tapetta Sodium hydroxide (Na(OH))
Compatibility
Works well with:
Water Carbomer Acrylates Copolymer Xanthan Gum Glycerin Fatty Acids
Use caution with:
L-Ascorbic Acid Citric Acid Lactic Acid Salicylic Acid AHAs Retinol Niacinamide (high conc.) Zinc compounds Aluminum compounds
Sodium Hydroxide is strongly alkaline and will neutralize acids directly, degrading acid-sensitive actives such as Vitamin C or AHAs if not carefully sequenced during formulation. It reacts with fatty acids to form soaps (saponification), which can be intentional in cleansers but undesirable in emollient-rich leave-on formulas. Always add to water phase in dilute form and adjust pH incrementally to avoid localized over-alkalinization.
Formulation notes
EU Cosmetics Regulation restricts final product pH rather than concentration directly; must not be used in concentrations that result in a dangerously high final pH. Typically used as a dilute solution (10–18% w/w stock) for safe handling. Final formulation pH should remain within skin-compatible range (approx. 4.0–8.0 depending on product type). Classified as a denaturant and pH adjuster by INCI; handle with appropriate PPE as it is corrosive in concentrated form.
Frequently asked questions
What is Sodium Hydroxide?
Sodium Hydroxide is a ph_adjuster, denaturant, saponifying agent used in cosmetic and personal-care formulation. Typical use level is 0.01%–5%. It is water-soluble.
What is Sodium Hydroxide used for?
Sodium Hydroxide is used as ph_adjuster, denaturant, saponifying agent in cosmetic and personal-care formulations.
What is the typical use level of Sodium Hydroxide?
Sodium Hydroxide is typically used at 0.01%–5% in the finished formulation. Always confirm against your supplier's technical data sheet.
What is the CAS number of Sodium Hydroxide?
The CAS registry number for Sodium Hydroxide is 1310-73-2. Its INCI name is Sodium Hydroxide.
What ingredients are compatible with Sodium Hydroxide?
Sodium Hydroxide works well with Water, Carbomer, Acrylates Copolymer, Xanthan Gum, Glycerin, Fatty Acids. Use caution when combining it with L-Ascorbic Acid, Citric Acid, Lactic Acid, Salicylic Acid, AHAs, Retinol, Niacinamide (high conc.), Zinc compounds, Aluminum compounds.
Related ingredients
- TriethanolaminePh Adjuster
- Ascorbic AcidAntioxidant
- Glycolic AcidActive
- Phytic AcidChelator
- Sodium BenzoatePreservative
- Sodium GluconateChelator