Liquid laundry detergent comprising lauryl ether sulfate and bicarbonate/metasilicate mixture

Abstract

The invention relates to a liquid laundry detergent composition suitable for cleaning textiles. In addition to at least one surfactant the detergent according to the invention comprises at least one water-soluble metasilicate, at least one water-soluble bicarbonate, at least one water-soluble glutamate and at least one polymeric rheology modifier in an aqueous medium. These components form a detergent framework allowing to reduce the amount of surfactant(s) compared to conventional liquid detergents, which is advantageous for economic, safety and environmental reasons, as less surfactants are consumed and subsequently disposed into wastewater to achieve the similar washing/cleaning performance.

Claims

1. A liquid laundry detergent, comprising at least one surfactant in an aqueous medium, characterised in that said surfactant is sodium lauryl ether sulphate present in amount of 1 to 25 wt %, wherein the detergent further comprises 0.1 to 5.0 wt % of sodium metasilicate, 0.1 to 10 wt % of sodium bicarbonate, 0.01 to 1 wt % of sodium glutamate, and 0.1 to 0.8 wt % of xanthan gum.

2. The detergent according to claim 1, wherein the weight ratio of sodium glutamate to sodium bicarbonate ranges from 1:12 to 12:1.

3. The detergent according to claim 1, wherein the weight ratio of xanthan gum to sodium lauryl ether sulphate is from 1:15 to 1:40.

4. The detergent according to claim 1, wherein the pH of the detergent ranges from 7.5 to 8.8.

5. The detergent according to claim 1, further comprising at least one additive the group consisting of further anionic surfactants, nonionic surfactants, amphoteric surfactants, phosphonates, enzymes, emulsifiers, opacifying agents, dyes, complexing agents, preservatives, perfumes and stabilizers.

6. The detergent according to claim 1, further comprising an optical brightener.

7. The detergent according to claim 1, further comprising a dye transfer inhibitor.

8. The detergent according to claim 5, wherein the complexing agent is trisodium citrate.

9. The detergent according to claim 5, comprising at least one further comprises at least one enzyme stabilizer the group consisting of formic acid, water-soluble formate, calcium chloride, glycerine and 1,2-propylene glycol.

Description

EXAMPLES

Example 1a: Preparation of a Universal Laundry Detergent (Dosage 75 ml Per One Washing Cycle)

(1) The following mixing instruction refers to a volume of the product of 1000 ml. 2.87 g of xanthan gum was added to 667.26 g of demineralized water and mixed vigorously for about 45 minutes until it was dissolved completely. Next, 10.64 g of sodium metasilicate pentahydrate, 2.66 g of sodium glutamate and 31.91 g of sodium bicarbonate were added one after another and the mixture was mixed after addition of each of the constituents until it was completely dissolved. Next 5.53 g of citric acid and 0.085 g of formic acid were added and mixed. The mixture was left for 15 minutes without mixing in order to swell. Next 48.4 g sodium laureth sulphate was added and the mixture was mixed. Further, the following materials could be also add to the mixture at this step: alcohols C13-15, branched and linear, ethoxylated; glycerine; sodium diethylenetriamine pentamethylene phosphonate. The product became viscous. Next, a perfume oil, a colorant, a preservation agent and an optical brightener were added and mixed until the product became less viscous. The pH of the mixture was kept at the level between 7.5 and 8.8. Next, enzymes were added and the mixture was mixed. Finally calcium chloride and the rest of water were added and the laundry detergent was mixed for 20 minutes. The content of the components and their function in the universal laundry detergent are presented in Table 2.

(2) TABLE-US-00002 TABLE 2 Composition of a universal laundry detergent of Example 1a. Chemical name CAS INCI wt % Alcohols, C12-14, 68891-38-3 SODIUM 4.55 ethoxylated, LAURETH sulfates, sodium salts SULFATE Alcohols, C13-15, 157627-86-6 — 4.00 branched and linear, ethoxylated Glycerine 56-81-5 GLYCERIN 3.01 Sodium bicarbonate 144-55-8 SODIUM 3.00 BICARBONATE Sodium metasilicate 10213-79-3 SODIUM 1.00 pentahydrate METASILICATE PENTAHYDRATE Diethylene- 22042-96-2 SODIUM 0.96 triamine- DIETHYLENE- penta(methylene TRIAMINE phosphonic acid) PENTAMETHYLENE- sodium salt PHOSPHONATE Citric acid 5949-29-1 CITRIC ACID 0.52 monohydrate Perfume — PARFUM 0.40 Disodium 4,4′- 27344-41-8 DISODIUM 0.30 bis(2-sulfon- DISTYRYLBIPHENYL atostyryl)biphenyl DISULFONATE Xanthan Gum 11138-66-2 XANTHAN GUM 0.27 Monosodium 142-47-2 SODIUM GLUTAMATE 0.25 glutamate Formic acid 64-18-6 FORMIC ACID 0.085 Protease 9014-01-1 SUBTILISIN 0.0528 Calciumchlorid 10043-52-4 CALCIUM CHLORIDE 0.0200 Cellulase 9012-54-8 CELLULASE 0.0185 Mannanase 37288-54-3 MANNANASE 0.0169 (mannan endo-1,4-beta- mannosidase Pectate lyase 9015-75-2 PECTAT LYASE 0.0166 Lipase 9001-62-1 LIPASE 0.0141 Alpha-amylase 9000-90-2 ALPHA-AMYLASE 0.0097 1,2-Benzoisothiazol- 2634-33-5 BENZISOTHIA- 0.0049 3(2H)-on ZOLINONE Pyridin-2-thiol- 3811-73-2 SODIUM PYRITHIONE 0.00240 1-oxide, sodium salt 2-Methyl-4- 2682-20-4 METHYLISOTHIA- 0.00083 isothiazolin-3-on ZOLINONE Colorant — COLORANT 0.00074 Water 7732-18-5 AQUA up to 100

(3) The characteristics of the universal laundry detergent (dosage 75 ml):

(4) pH: 7.5-8.8

(5) Dry matter: 15.5-18 wt %

Example 1b: Preparation of a Universal Laundry Detergent (Dosage 55 ml)

(6) The following mixing instruction refers to a volume of the product of 1000 ml. 3.23 g of xanthan gum was added to 466 g of demineralized water and mixed vigorously for about 45 minutes until it was dissolved completely. Next, 12.92 g of sodium metasilicate pentahydrate, 2.69 g of sodium glutamate and 16.15 g of sodium bicarbonate were added one after another and the mixture was mixed after addition of each of the constituents until it was completely dissolved. Next 5.6 g of citric acid and 0.085 g formic acid were added and mixed. The mixture was left for 15 minutes without mixing in order to swell. Next 121.3 g sodium laureth sulphate, was added and the mixture was mixed. Further the following materials could be also add to the mixture at this step: alcohols C13-15, branched and linear, ethoxylate; glycerine; sodium diethylenetriamine pentamethylene phosphonate. The product became viscous. Next, a perfume oil, a colorant, sodium citrate, a preservation agent and an optical brightener were added and mixed until the product became less viscous. The pH of the mixture was kept at the level between 7.5 and 8.8. Next, enzymes were added and the mixture was mixed. Finally calcium chloride and the rest of water were added and the laundry detergent was mixed for 20 minutes. The content of the components and their function in the universal laundry detergent are presented in Table 2.

(7) TABLE-US-00003 TABLE 3 Composition of a universal laundry detergent of Example 1b. Chemical name CAS INCI wt % Alcohols, C12-14, 68891-38-3 SODIUM LAURETH 12.130 ethoxylated, SULFATE sulfates, sodium salts Alcohols, C13-15, 157627-86-6 —  7.700 branched and   linear, ethoxylated   Glycerine 56-81-5 GLYCERIN  1.720 Sodium bicarbonate 144-55-8 SODIUM  3.00 BICARBONATE   Trisodium citrate 6132-04-3 SODIUM CITRATE  1.700 dihydrate   Sodium metasilicate 10213-79-3 SODIUM  1.200 pentahydrate METASILICATE   PENTAHYDRATE   Diethylene- 22042-96-2 SODIUM  0.960 triamine- DIETHYLENE-   penta(methylene TRIAMINE   phosphonic acid) PENTAMETHYLENE-   sodium salt PHOSPHONATE   Citric acid 5949-29-1 CITRIC ACID  0.520 monohydrate   Perfume — PARFUM  0.500 Disodium 4,4′-bis(2- 27344-41-8 DISODIUM  0.345 sulfon- DISTYRYLBIPHENYL   atostyryl)biphenyl DISULFONATE   Xanthan Gum 11138-66-2 XANTHAN GUM  0.300 Mononatriumglutamat 142-47-2 SODIUM GLUTAMATE  0.250 Protease 9014-01-1 SUBTILISIN  0.0984 Formic acid 64-18-6 FORMIC ACID  0.0850 Cellulase 9012-54-8 CELLULASE  0.0344 Lipase 9001-62-1 LIPASE  0.0262 Pectate lyase 9015-75-2 PECTAT LYASE  0.0222 Mannanase (mannan 37288-54-3 MANNANASE  0.0207 endo-1,4-beta-   mannosidase)   Calcium chloride 10043-52-4 CALCIUM CHLORIDE  0.0200 Alpha-amylase 9000-90-2 ALPHA-AMYLASE  0.0180 1,2-Benzoisothiazol- 2634-33-5 BENZISOTHIA-  0.00640 3(2H)-on ZOLINONE   Pyridin-2-thiol- 3811-73-2 SODIUM PYRITHIONE  0.00240 1-oxid,   sodium salt   2-Methyl-4- 2682-20-4 METHYLISOTHIA-  0.00160 isothiazolin-3-on ZOLINONE   Colorant — COLORANT  0.00074 Water 7732-18-5 AQUA up to 100

(8) The characteristics of the universal laundry detergent (dosage 55 ml):

(9) pH: 7.5-8.8

(10) Dry matter: 24.0-27.0 wt %

(11) Density: 1.050-1.060 g/cm.sup.3

Example 2: Biodegradability of the Detergent According to the Invention

(12) The biodegradability of the laundry detergent according to the invention (A) (obtained according to the example 1b) was compared with the biodegradability of four commercial laundry detergents (B)-(E), available on the market, measured as BOD.sub.5/COD (biochemical oxygen demand after 5 days/chemical oxygen demand) ratio (see Table 4). This ratio indicates the percentage of components that can be degraded by biological means e.g. in a wastewater treatment plant. High BOD.sub.5/COD indicates good biodegradability.

(13) TABLE-US-00004 TABLE 4 Biodegradability comparison Dosage COD for one for one Descrip- washing washing Sample tion/ BOD.sub.5/ COD* BOD.sub.5 cycle cycle ID Name COD mg/l mg/l ml mg 1 A 0.542 590.000 320.000 55 32.450 2 B 0.275 1200.000 330.000 55 66.000 3 C 0.283 1200.000 340.000 60 72.000 4 D 0.313 1500.000 470.000 50 75.000 5 E 0.353 1500.000 530.000 55 82.500 *(according DIN ISO 15705: 2003-01 (H45) **(according DIN EN 1899-1 H51 (1998-05))

(14) The quotient of BOD.sub.5 and COD shows impressively reduced ecological footprint of the detergent according to the invention compared to prior art detergents The quotient is significantly higher than that of other products on the market. Another good indicator of the improved eco-friendly properties of the detergent according to the invention is the chemical oxygen demand for a wash cycle (according to the dosage indicated on the label). Table 4 shows that the chemical oxygen demand for a single wash cycle is approximately half of the respective value of this parameter for prior art detergents available on the market. Accordingly, the amount of biodegradable substances released to waste water is significantly reduced in case of the liquid detergents according to the present invention calculated with respect to a dosage per single wash cycle. To sum up, it is noted that the detergent according to the invention (sample A) shows the best biodegradability compared to the other tested products (B)-(E) available on the market.