LABSA and SLES are two of the most widely used anionic surfactants in India's home care and personal care industries. Both clean and foam, but they behave very differently in a formulation. Choosing the right one, or the right blend, depends on whether you are making a detergent powder, a dishwash liquid or a shampoo.
What is LABSA?
LABSA (Linear Alkyl Benzene Sulphonic Acid) is made by sulfonating linear alkylbenzene. It is supplied in its acid form as a viscous brown liquid, usually at 90% or 96% active matter. Because it is a strong acid, LABSA is neutralised during formulation, typically with caustic soda or soda ash, to form sodium linear alkylbenzene sulfonate (LAS), the actual cleaning agent. LAS is a powerful, cost-efficient detergent and the backbone of most detergent powders, bars and many dishwash formulations.
What is SLES?
SLES (Sodium Lauryl Ether Sulphate) is made by ethoxylating and then sulfating lauryl alcohol and neutralising the result. It is supplied ready to use as a neutral salt, commonly as a 70% active paste or a 28% active liquid. SLES produces rich, creamy foam, is milder on skin than LAS or SLS, and thickens easily when salt is added, which is why it dominates shampoos, body washes, handwashes and liquid detergents.
LABSA vs SLES at a glance
| Property | LABSA | SLES |
|---|---|---|
| Chemical type | Sulfonic acid (anionic) | Ether sulfate salt (anionic) |
| Supplied as | Acid liquid, 90% / 96% active | Paste (70%) or liquid (28%) |
| Needs neutralising? | Yes, before or during formulation | No, already neutralised |
| Handling | Corrosive; needs acid-safe handling | Far easier to handle |
| Foam | Good, sharp foam | Rich, dense, creamy foam |
| Mildness on skin | Lower | Higher |
| Hard-water tolerance | Lower; relies on builders | Better |
| Thickening with salt | Limited | Excellent |
| Cost | Lower cost per kg of active | Higher |
| Typical uses | Detergent powders and bars, dishwash bars, toilet and acidic cleaners | Shampoos, body wash, handwash, dishwash and laundry liquids |
Where LABSA is the better choice
LABSA is the workhorse for detergent powders and bars, where it is neutralised in the mixing process and supported by builders such as STPP that soften the water. Its low cost per unit of cleaning power makes it the default for price-sensitive mass-market laundry products. It is also used in acidic cleaners and many economical dishwash formulations.
Where SLES is the better choice
SLES is the first choice for products that touch skin, such as shampoos, body washes and handwashes, usually paired with a mild co-surfactant like CAPB. It is also preferred in clear liquid detergents and dishwash liquids, where its foam quality and easy salt thickening help create a premium-feeling product.
Using LABSA and SLES together
Many dishwash liquids and liquid detergents use both: neutralised LABSA for cost-efficient degreasing, and SLES for foam, mildness and viscosity. Blending the two often gives better performance per rupee than either surfactant alone.
SLES 70% vs SLES 28%: what is the difference?
The two grades contain the same surfactant at different concentrations. SLES 70% is a concentrated paste that is cheaper to transport and store per kilogram of active matter. SLES 28% is a pourable liquid that is easier to dose. When diluting SLES 70%, add the paste slowly to water with stirring rather than adding water to the paste. In between roughly 30% and 60% active, SLES forms a very thick gel phase that is hard to mix.
A greener alternative: MES
Formulators looking for a bio-based anionic surfactant with strong hard-water performance often blend in MESAPON® Methyl Ester Sulfonate (MES). Read our comparison of MES and LABSA to see where it fits.