SURFACTANTS

Sparge foam height 1 % active- pH 3.5

Sparge foam height 1 % active- pH 8.5

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of these foams— bubble size, uniformity and persistence— is critical for their cleaning power and sensorial qualities. 2, 3

These formats extend contact time with surfaces, allowing surfactants to act longer on contaminants, softening and lifting dirt and grease more efficiently while minimising manual scrubbing and chemical burden. The sensory quality of foam— its feel, visual appearance and lasting presence— plays a key role in consumer satisfaction where it is a sensory cue for cleanliness. In personal care, where tactile experience directly influences perceived efficacy and product enjoyment, foam structure manipulation has been at the forefront.

Taking a cue from the cosmetics industry, we are now seeing household brands differentiating products by encouraging sensorial cleaning rituals. This is often achieved with the introduction of fragrances. However, a new wave of foam surface cleansers offers enhanced efficiency in conjunction

with satisfyingly rich foam, possibly enabling foam quality to hold greater appreciation for consumers.

Automotive snow foam cleaning demonstrates these principles: surfactant solutions, delivered via a snowfoam lance with a mesh filter, cling to vehicle surfaces, increasing dwell time, and resulting in measurable water and chemical savings. A Nissan study found a reduction in water consumption by 44 %. 3

Automotive detailers and car enthusiasts are turning to snowfoam as the preferred wash method for multiple reasons. Firstly, the increased contact time achieved allows the surfactants to soften and lift residues from the surface, reducing the need for labour and time-intensive scrubbing. Secondly, by limiting the abrasive scrubbing action on the car, the risk of causing damage to the lacquer coating is reduced. The benefits of snowfoam can improve efficiency in the transport system, with less downtime required for cleaning time required for buses and lorries.

Surfactant selection: Chemistry & performance

Surfactants fall into four classes: anionic, cationic, nonionic and amphoteric. Each chemical structure offers unique properties for foam formation, stability, and cleaning performance.

Anionics are classified by their negatively charged groups, which can include sulphates and phosphate structures. Alkyl sulfates are stable at a wide pH range, these high-foaming surfactants create strong, stable foams.

Traditional anionic surfactants like sodium lauryl sulfate( SLS) are known for strong cleaning and foaming, but SLS in particular is associated with higher irritation potential and can cause dryness or barrier disruption, especially with repeated use or at higher concentrations.

Sodium cocosulfate( SCS) is a coconut-derived milder option than its more commonly used than its SLS counterpart, which is typically palmderived. They have a wide usage in personal care, industrial, household and automotive cleaning applications.

NOV / DEC 2025 SPECCHEMONLINE. COM

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