So
Sodium Hydroxide
Sodium Hydroxide
A pH adjuster that brings a product to its target range. Only a trace is left once it has reacted.
What it does
It’s added in tiny amounts to bring a finished product to the right pH, which matters for ingredients like vitamin C or exfoliating acids that only work in a certain range. By the time the product is on the shelf it has reacted and been neutralized, so only a trace is left.
The EU’s ingredient database lists it as a pH adjuster (sets how acidic the product is).European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗
Also known as
lye, caustic soda
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