Economical Liquid

Addition Order & Process

The economical tier targets price-sensitive markets where the lowest cost per wash is the overriding purchase driver. Formulation FC-6.1-E achieves this through maximized LABSA content (neutralized in situ to LAS), minimal SLES, and sodium chloride as the sole thickener. Active matter at 8–10% is at the lower limit for acceptable cleaning of lightly soiled cotton and synthetic fabrics in soft to medium water.> Formulation Card FC-6.1-E: Economical Liquid Laundry Detergent > > | Raw Material | % w/w (as received) | Function | Notes | > |:—|:—:|:—|:—| > | Deionised water | 84.65 | Solvent | To 100%; conductivity <5 μS/cm | > | LABSA 96% | 5.50 | Primary surfactant | Neutralised in-process to LAS | > | Caustic soda (NaOH), 50% | 1.45 | Neutralising agent | 0.26 kg NaOH per kg LABSA | > | SLES 70% | 3.00 | Primary surfactant | Creamy foam contribution | > | Sodium chloride (NaCl) | 2.50 | Thickener (salt-curve) | Adjust for target viscosity | > | Sodium citrate | 1.00 | Builder/chelator | Soluble; liquid-compatible | > | CMC (sodium carboxymethyl cellulose) | 0.50 | Thickener/anti-redeposition | Low-viscosity grade | > | Colourant (liquid dye) | 0.01 | Aesthetic | pH-stable acid dye | > | Fragrance | 0.20 | Aesthetic | Economy grade; 0.2% loading | > | Preservative (MIT/BIT blend) | 0.14 | Preservation | 14 ppm active isothiazolinone | > | Citric acid (50% solution) | q.s. | pH adjustment | Target pH 7.5–8.5 | > | Total | 100.00 | | | > > Addition Order & Process: > 1. Charge 80% of the deionised water into the main mixing vessel. Begin agitation at 200–300 rpm. > 2. Add caustic soda solution slowly. Caution: exothermic; do not exceed 40 °C. > 3. Add LABSA 96% slowly with continuous mixing. Neutralisation generates heat; maintain temperature below 45 °C. Mix for 15 minutes until homogeneous. > 4. Add SLES 70%. Mix for 10 minutes. > 5. Dissolve sodium citrate in remaining warm water (30 °C); add to main vessel. Mix 5 minutes. > 6. Predisperse CMC in a small portion of water (5× its weight) at 30 °C; add to main vessel. Mix 10 minutes. > 7. Add sodium chloride. Mix 15 minutes. Check viscosity (target: 100–300 cP at 25 °C, Brookfield LV, spindle #2, 30 rpm). > 8. Add colourant, fragrance, and preservative sequentially. Mix 5 minutes each. > 9. Adjust pH to 8.0 ± 0.5 with citric acid solution. > 10. Deaerate under vacuum (–0.05 bar) for 10 minutes if foam is present. > > Expected Parameters: pH 8.0 ± 0.5; viscosity 100–300 cP; active matter (as LAS + SLES, anionic) 8.0–10.0% w/w (two-phase titration, ISO 2271); density 1.02–1.04 g/cm³. Shelf life: 12 months at 5–40 °C.

Formulation Notes

The economical formulation illustrates the trade-offs inherent in cost-driven design. LABSA neutralised in situ is the cheapest anionic surfactant on an active basis (cost index ≈85 vs. LAS=100) but produces coarser foam and higher skin irritation potential than pre-neutralised SLES.The absence of enzymes, optical brighteners, and nonionic co-surfactants limits stain removal on protein and oily soils; performance in hard water is adequate only up to approximately 150 mg/L CaCO₃, above which calcium LAS precipitation causes visible clouding and reduced detergency. Sodium chloride at 2.5% thickens via the salt-curve mechanism (see Section 6.3.1), but viscosity is sensitive to temperature and surfactant batch variation — quality control must verify viscosity on every batch.