What it is
The register’s chemical name for it: “Sodium sulphate.”
- EU register name (INCI)
- SODIUM SULFATE
- CAS number
- 7727-73-3 / 7757-82-6
- EC number
- / 231-820-9
What the register lists it for
These are the uses the European Commission’s CosIng register lists for Sodium Sulfate in any cosmetic, hair roles first. They say why a maker might add it, not what it does in one formula, and they aren’t a safety rating.
- Viscosity controlling
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Makes a product thicker or thinner, so a gel holds its shape or a shampoo pours. Gums, cellulose and some salts carry this role.
Register definition: “Increasing or decreasing the viscosity (thickness) of cosmetics.”
- Bulking
-
Adds volume to a product without reacting with anything.
Register definition: “Non-reactive (chemically inert), solid ingredients that dilute other solids and/or increase the volume of cosmetic products.”
Where it sits on each label
US labels list ingredients from most to least, except that those at 1% or less may follow in any order. A name near the top is a large part of the formula. A label doesn’t mark where the 1% point falls, so further down, the order says little about how much is in it.
- Shampoos 2 labels First five names: 0 of 2 Shampoos without it
- Clarifying shampoos 2 labels First five names: 0 of 2 Clarifying shampoos without it
Every label, product by product (4)
- Cantu Ultra Moisture Nourishing Shampoo Shampoo 16th of 31 names
- OLAPLEX No.4 Bond Maintenance Strengthening Shampoo Shampoo 61st of 78 names
- Kristin Ess Deep Clean Clarifying Shampoo Clarifying shampoo 8th of 39 names
- OLAPLEX No.4C Bond Maintenance Clarifying Shampoo Clarifying shampoo 36th of 55 names
Each line runs from the first name on a label to the last; a dot is where this ingredient sits. Makers change formulas now and then; if the list on your bottle differs, go by your bottle.
Your next step
Other viscosity controlling ingredients on these labels
- Butyrospermum Parkii (Shea) Butter 57 labels
- Hydroxypropyl Starch Phosphate 5 labels
- Cellulose 4 labels
- Hydrolyzed Wheat Starch 4 labels
- Tapioca Starch 4 labels
- Potassium Chloride 2 labels
Updated · The name, numbers and uses come from the European Commission’s CosIng entry (CC BY 4.0); we write the uses in US spelling and put the hair ones first. The labels are each maker’s own. The order rule is the FDA’s Cosmetics Labeling Guide. All our sources are on the Sources page.