Economical Dishwashing Liquid

Ingredients

Ingredient	INCI / Description	% w/w	Function	Addition Order
Deionized water	Aqua	73.0	Solvent	1
Sodium hydroxide (50%)	Sodium hydroxide	2.5	Neutralizing agent	2
LABSA (96% active)	Linear alkylbenzene sulfonic acid	8.0	Primary anionic surfactant	3
SLES (70%)	Sodium laureth sulfate	5.0	Secondary surfactant, foam booster	4
Sodium chloride	Sodium chloride	1.0	Viscosity modifier	5
Citric acid (50%)	Citric acid	qs	pH adjustment to 6.5–7.5	6
Colorant (FD&C Yellow #5)	CI 19140	0.005	Aesthetic	7
Lemon fragrance	Fragrance (parfum)	0.3	Sensory	8
Preservative (sodium benzoate)	Sodium benzoate	0.5	Microbial stability	9
Total		~100

Addition Order & Process

Procedure: Charge the main vessel with deionized water. Add sodium hydroxide solution and begin moderate agitation (300–400 rpm). Slowly add LABSA; the exothermic neutralization reaction will raise the batch temperature by 8–12°C. Cool to 40°C before adding SLES. Dissolve sodium chloride gradually and mix for 15 min; adjust pH with citric acid. Add colorant, fragrance, and preservative in sequence with 5-min mixing intervals between additions.

Formulation Notes

This formulation targets the lowest unit-cost segment. It uses linear alkylbenzene sulfonic acid (LABSA) partially neutralized with sodium hydroxide as the primary surfactant, supplemented with a modest level of SLES for foam quality. The total active matter of 10–12% is sufficient for light-duty domestic dishwashing. Viscosity is achieved solely through sodium chloride electrolyte thickening; no polymeric thickeners are employed.

Formulation Card FC-8.1-E: Economical Dishwashing Liquid

Properties: Active matter 10.5% ± 0.5% (two-phase titration, ISO 2271); pH 6.8–7.2 (10% aqueous solution, 25°C); viscosity 150–300 cP (Brookfield LV, spindle #2, 30 rpm, 25°C). Foam height (Ross-Miles, 0.25% solution, 40°C, initial) 165 ± 10 mm. Expected shelf life: 24 months at 5–40°C.

Notes: The LABSA:SLES ratio of 8:5 (as-supplied) provides adequate foam but limited grease cutting on heavy lipid soils. Sodium chloride thickening exhibits a narrow electrolyte window; exceeding 1.5% risks salting out the anionic surfactant and inducing phase separation. Skin mildness is modest; prolonged contact may cause defatting of the stratum corneum.