Calcium Hydroxide
What is Calcium Hydroxide?
Calcium hydroxide, or Ca(OH)₂, is an inorganic compound appearing as a white, crystalline powder formed by reacting quicklime (calcium oxide) with water. It exhibits strong alkaline properties due to hydroxide ions. In cosmetics, it features in hair care products like relaxers and straighteners, depilatory creams, and occasional cleansing or oral care items. Its primary function involves raising pH levels to optimize ingredient activity, boost preservative function, and ensure formulation stability. By creating a high-pH environment, it inhibits certain microbial growth, supporting product integrity. Typically applied in dilute amounts, it aids in achieving desired texture and efficacy in alkaline-dependent products without altering sensory qualities significantly.
Roles in Formulation
This ingredient serves the following purposes in cosmetic formulations:
Benefits
Supports pH adjustment to enhance ingredient performance and stability
Acts as a buffering agent to maintain consistent pH levels
Provides antiseptic effects through alkaline environment
Who It's For
A quick guide for who this ingredient may suit (and who should be cautious).
| Who May Benefit | Who Should Avoid |
|---|---|
| Users of hair relaxers needing stable alkaline formulations | Those with highly sensitive or reactive skin |
| Individuals with products requiring pH optimization for efficacy | Individuals prone to irritation from alkaline substances |
| People seeking non-comedogenic ingredients in cleansing products | Users applying products near eyes or mucous membranes |
Safety Notes
- EWG scores range from 1 to 4, indicating low to moderate overall concern
- Deemed safe in cosmetics at typical use levels by expert reviews
Frequently Asked Questions about Calcium Hydroxide
What does calcium hydroxide do in skincare?
It adjusts and buffers pH to support formulation stability and ingredient function.
Is calcium hydroxide comedogenic?
No, it has a comedogenic rating of 0, unlikely to clog pores.
Can it cause irritation?
Possible in sensitive individuals due to its alkaline nature; use formulated products.