Common Name(s): Sodium toluenesulfonate,sts,sodium methylbenzenesulfonate,nats
CAS Number: 657-84-1
DESCRIPTION
What It Does: Keeps liquid formulas clear and easy to pour by helping surfactants dissolve properly in water.
Why It's Used: Used as a hydrotrope to improve clarity and reduce viscosity in shampoos, liquid cleansers, and concentrated surfactant systems.
How It Works: The methyl-substituted benzene ring provides intermediate hydrophobicity between benzene and xylene sulfonates; disrupts surfactant micellar packing to increase cloud points and reduce viscosity.
Typically Found In: Shampoos,liquid cleansers,body washes,surfactant concentrates
TECHNICAL DETAILS
Primary Category: Functional ingredient – surfactant
Secondary Functions: Hydrotrope,viscosity controlling
Application Areas:
Facial Skincare
Body Care
Hair Care
Beard Care
Color Cosmetics (Makeup)
Dietary/Oral Supplements
Typical Concentration Range: 0.5%–5%
SOURCING & ETHICS
Vegan Status: Yes
Halal Status: Yes
Source Notes: Synthetic; derived from toluene (petrochemical) sulfonation followed by sodium neutralization.
SKIN COMPATIBILITY
Irritancy Rating: 1/5 – very low
Comedogenicity Rating: 0/5 – non-comedogenic
Sensitivity Concerns: Non-irritating at typical use levels.
Safe for Sensitive Skin: Yes
SAFETY & COMPATIBILITY
Safety Profile: Good safety profile. ewg score: 1–2.
Works Well With: Anionic surfactants,amphoteric surfactants,nonionic surfactants
Avoid Combining With: No significant incompatibilities
SCIENTIFIC NOTE
Toluenesulfonate (ts) is a monosubstituted benzene hydrotrope with lower hydrophobe efficiency than xylene or cumene sulfonates; often used in combination with other hydrotropes for optimized performance; cas 657-84-1.
Last Verified: 2026-03-27
Primary Sources: Cosing database,inci dictionary,chemicalbook 657-84-1