Low-Foam Alkali-Free Degreaser — Hydrotrope (Betaine/Sulfonate) Guidance

Use this sheet to shortlist hydrotropes for neutral / alkali-free degreasing systems where foam control is critical (spray, circulation, ultrasonic). Values are practical guidance and must be validated on your soil / substrate / line conditions.

Application

Soil Type

Hard Water Tolerance Needed

Foam Priority

Recommended Hydrotrope Class

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Suggested Dosage (concentrate)

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Foam Expectation

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Notes

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Hydrotrope Options (Shortlist)

Pick one primary hydrotrope and validate in your surfactant + solvent system. Mix order matters for clarity and stability.

Class	Typical Examples	Foam	Strength
Sulfonate Hydrotrope	SXS / SCS (xylene/cumene sulfonate)	Low	High solubilization, cost-effective
Betaine / Amphoteric	CAPB, hydroxysultaine, iminodipropionate	Low → very low	Hard-water tolerant, stable, mild corrosion profile
Alkanoate Hydrotrope	Sodium heptanoate / caprylate	Very low	Excellent spray compatibility, good wetting

Alkali-free Low foam Spray compatible Hard water tolerant (betaine)

Lab Notes / Trial Observations

Practical Mixing Order + Starter Skeleton

1) Water → 2) Hydrotrope → 3) Chelant → 4) Nonionic low-foam surfactant → 5) Solvent (if any) → 6) Inhibitor → 7) Preservative → adjust pH (neutral range)

Component	Typical % (Concentrate)
Water	Balance
Low-foam nonionic (EO/PO block)	5–8%
Hydrotrope (selected)	2–6%
Solvent (DPM / glycol ether)	0–10%
Chelant (GLDA / EDTA)	0.5–2%
Corrosion inhibitor	0.3–1%
Preservative	As needed

Avoid high-foam anionics for spray lines. Validate on: foam height, oil carry-over, rinseability, and substrate compatibility.