CN1214100C - Method and composition for laundering fabrics - Google Patents

Abstract

A method of laundering fabrics comprising: a washing step in which the fabrics are immersed in an aqueous wash liquor comprising a detergent surfactant, a detergency builder and optionally other detergent ingredients; (ii) a rinsing step in which the fabric is immersed for at least 30 seconds in an aqueous rinse liquor, said rinse liquor being free of surfactant and containing a detergency builder in a concentration in the range 0.1 to 10 g/l. A composition suitable for use in carrying out the method, comprising: (a)10-99.95% by weight of a detergency builder, (b)0-90% by weight of a pH buffer and (c) an optical brightener and/or a perfume, wherein the ratio of (a) to (b) is from 99.95: 0 to 10: 90, said composition being substantially free of organic surfactants.

Description

Method and composition for laundering fabrics

field of invention

The present invention relates to methods and compositions for laundering fabrics.

Background of the invention

In countries where fabrics are hand washed, even with premium laundry cleaning products, the level of cleanliness achieved is often disappointing.

One obvious way to improve hand wash performance is to try to improve the ingredients in the main wash detergent formulation. However, the inventors have now realized that this technical problem can be solved by a new and surprising method by which a detergency aid is applied to the fabric during the rinse process. Also improves overall cleaning/stain removal and, in some cases, aids in stain removal.

US 4110075A discloses a washing method comprising a washing phase followed by a rinsing phase. The rinse solution may contain 0.02-0.1 g/l of organic acid.

Definition of the invention

The invention provides a method of washing fabrics, the method comprising:

(i) a washing step in which fabrics are soaked in an aqueous wash liquor comprising detergent surfactant, detergency aid and optionally other detergent ingredients;

(ii) a rinse step in which the fabric is soaked for at least 30 seconds in an aqueous rinse solution substantially free of surfactants and containing detergency aid at a concentration in the range 0.1-10 g/l .

A second aspect of the present invention provides a composition for treating laundered fabrics during the rinse process, the composition comprising:

(a) 10-99.95% by weight, preferably 15-99.0% by weight, more preferably 20-95% by weight of water-soluble detergency aids,

(b) 0-90% by weight, preferably 0-85% by weight, more preferably 0-80% by weight, more preferably 0-50% by weight of pH buffering agent, the weight ratio of (a) to (b) is 99.9:0 - 10:90, preferably 99:0-15:85, more preferably 95:0-20:80, and

(c) Optical brighteners and/or fragrances, the composition being substantially free of organic surfactants.

Detailed description of the invention

The method according to the invention is essentially characterized in that the detergent aid is included in the rinse liquor in a concentration of 0.1 to 10 g/l. The rinse must be substantially free of surfactants. For example, the rinse should contain <0.25 g/l, more preferably <0.1 g/l, most preferably <0.05 g/l non-soap synthetic surfactant. It is particularly preferred that the rinse solution is completely free of such surfactants. The rinse can also be substantially soap-free.

Detergency aids in rinse solutions

Preferably the concentration of detergency aid is 0.25-5 g/l, more preferably 0.5-5 g/l.

A wide range of hydrotropes can be used in the method of the invention. They can be water-soluble, water-insoluble or partially soluble. One or more such adjuvants may be used. But most preferred is sodium tripolyphosphate. Other water-soluble detergent builders that can be used in this method are alkali metal citrates, alkali metal carbonates (with calcite), nitrilotriacetates and sodium nitrilotriacetate (NTA). Aluminosilicates are typical insoluble aids.

The preferred amount of auxiliary agent is such that pCa≥4, preferably ≥5.

Preferably, the detergency aid in step (ii) of the method of the present invention is selected from the group consisting of sodium tripolyphosphate, alkali metal citrates, orthophosphates, alkali metal carbonates, aluminosilicates and alkali metal nitrilotriethyl salts and their mixtures.

buffer

According to the second aspect of the present invention, the optional pH buffering agent (b) is present in an amount of 0-90% by weight, preferably 0-85% by weight, more preferably 0-80% by weight, especially 0-50% by weight of the composition weight exists. When present, pH buffering agents are preferably present in an amount of at least 2% by weight.

Very preferably the pH of the rinse solution is ≥ 8.0. For this purpose, a specific alkaline buffer can be added and/or a non-build or semi-detergency build buffer such as alkali metal carbonates ( without calcite) and/or acid carbonates and/or silicates. Thus, a preferred embodiment involves the use of sodium tripolyphosphate as builder, selected from the group consisting of alkali metal carbonates (without calcite), orthophosphates, acid carbonates and/or silicates in the rinse solution. Reagents are buffered to a pH greater than 8.0. However, if the detergency aid contains citrate and/or NTA and/or aluminosilicate, or consists mainly or exclusively of citrate and/or NTA and/or aluminosilicate, buffering to pH is only required ≥5.5.

other optional ingredients

It is also preferred to include one or other optional ingredients such as ingredients selected from optical brighteners, perfumes, starches, enzymes such as lipases, soil release polymers, photobleaches and bluing agents. In the case of the compositions of the present invention, optical brighteners and/or perfumes are necessary. For products used in the final rinse it is highly preferred to include an antifoam agent.

On the basis of the foregoing content, a kind of clay, such as bentonite type, may also be additionally or selectively included, for example, clay having a number-average particle size of not more than 2.0 μm. This also helps remove stains.

product form

The rinse may be used with the composition of the invention in any suitable form, for example as a powder composition, liquid, cream, gel, bar, tablet or granular product.

The present invention also provides a laundry detergent product comprising: (i) a first composition comprising a detergent surfactant, a detergency builder and optionally other detergent ingredients, and (ii) ) A rinse treatment composition of the present invention.

Preferably the first composition (i) is a particular laundry detergent composition. Preferably the first and second compositions are in separate primary packaging and in turn are packaged together in a common secondary packaging. More preferably the first composition (i) is a granular laundry detergent composition.

The invention is illustrated in more detail by the following non-limiting examples.

rinse formula

Composition A

Element percent present Sodium LAS Fatty Alcohol Ethoxylate (7EO) Fatty Alcohol Ethoxylate (3EO) Soda Ash Minor Components   25.00.51.523.4 margin total 100.0

test number product main wash rinse 1 rinse 2 rinse 3 A Composition A 2.5 g/l - - - B Composition A 2.5 g/l STP 2g/l Sodium Carbonate 0.2g/lPhotine C0.0135g/l - - C Composition A 2.5 g/l - - STP 2g/l Sodium Carbonate 0.2g/lPhotine C 0.0135g/l D. Composition A 2.5 g/l - - STP 2g/l Sodium Carbonate 0.2g/lPhotine C 0.0135 g/lLipolase 100T 0.003g/l E. Composition A 2.5 g/l - - STP 2g/l Sodium Carbonate 0.2g/l Photine C 0.0135g/l Repel-o-Tex PF 594 (from Rhodia) 0.025g/l

All main washes and rinses are performed in water at 24°FH (2:1 Ca:Mg).

experimental method

Artificial soil dispersions for this wash-resoiling step were produced according to the method described below.

artificial sebum composition

An artificial sebum composition comprising:

fatty acid

Glyceryl Tripalmitate

brominated olive oil

squalene

cholesterol

cetostearyl stearate mixture

artificial dirt composition

The artificial sebum composition was dispersed in water with carbon and iron oxide, using clay as a dispersant.

1. Washing conditions

soaking step temperature 25°C liquid: clothing 5:1 Duration of immersion 30 minutes total liquid volume 100ml water hardness 24°FH (Ca:Mg=2:1) total load weight 20g Repollution monitor 2 cotton sheets, 2 polyester/cotton sheets, 2 knitted polyester (3 of each in the pre-wash) reprecipitation monitor 5 cotton sheets, 5 polyester/cotton sheets load Load weight = 20g - (repollution and re-deposition monitor) cotton: polyester/cotton (33:67) mixing steps presence of ball bearings 50/pot stirring duration 10 minutes rinse step stirring duration 3 minutes liquid: clothing 10:1

total liquid volume 200ml water hardness 24°FH (Ca:Mg=2:1)

Repeat the rinse step 3 times, adding product to the first or last rinse as appropriate.

Results of reflectance data on woven cotton after 3 laundering resoiling cycles vs. initial reflectance and vs. control product

Measurement initial average A B C D E Repollution R460 ^* ΔRΔΔR 89.50- 63.57-25.930 74.9-14.611.33 80.55-8.9516.98 79.33-10.1715.76 79.94-9.5616.37 Repollution R460ΔRΔΔR 89.80- 69.72-20.080 84.06-5.7414.34 91.441.6421.72 89.910.1120.19 90.530.7320.81 Redeposition R460 ^* ΔRΔΔR 89.50- 86.12-3.380 89.26-0.243.14 89.06-0.442.94 89.15-0.353.03 87.5-21.38 redeposition R460ΔRΔΔR 89.50- 96.737.230 102.3712.875.64  102.4312.935.7  102.5913.095.86 102.9113.416.18

Results on Woven Polyester/Cotton

Measurement initial average A B C D E Repollution R460 ^* ΔRΔΔR 880- 76.93-11.070 81.5-6.54.57 84.46-3.547.53 87.78-0.2210.85 84.17-3.837.24 Repollution R460ΔRΔΔR 880- 81.58-6.420 87.07-0.935.49 90.822.829.24 93.725.7212.14 90.272.278.69 Redeposition R460 ^* ΔRΔΔR 87.90- 86.03-1.870 87.86-0.041.83 87.56-0.341.53 87.62-0.281.59 87.87-0.031.84 redeposition R460ΔRΔΔR 87.80- 92.344.540 94.446.642.1 93.775.971.43 94.326.521.98 94.827.022.48

Results on knitted polyester

Measurement initial average A B C D E Repollution R460 ^* ΔRΔΔR 87.50- 62.75-24.750 67.55-19.954.8 62.75-24.750 66.05-21.453.3 67.12-20.384.37 Repollution R460ΔRΔΔR 86.50- 62.13-24.370 67.68-18.825.55 62.66-23.840.53 66.13-20.374 67.09-19.414.96

Claims (17)

1. the method for a laundering of textile fabrics, it comprises:

(i) washing step is immersed in fabric in this step in the aqueous cleaning solution that comprises detergent surfactant, detergent auxiliary and optional other detergent ingredients;

(ii) a rinse step is soaked fabric 30 seconds in moisture rinsing liquid in this step at least, and described rinsing liquid contains＜the non-soap synthetic surfactant of 0.25g/l, contain the detergent auxiliary of concentration in the 0.1-10g/l scope.

2. the process of claim 1 wherein that the concentration of detergent auxiliary in the described rinsing liquid is in the scope of 0.25-5g/l.

3. the method for claim 2, the concentration of detergent auxiliary is in the scope of 0.5-5g/l in the wherein said rinsing liquid.

4. each method in the aforementioned claim, the wherein said step detergent auxiliary in (ii) comprises water-soluble additive.

5. the method for claim 4, the wherein said step detergent auxiliary in (ii) is selected from tripoly phosphate sodium STPP, alkali metal citrate, orthophosphoric acid salt, alkaline carbonate, silico-aluminate and basic metal nitrilotriacetic acid(NTA) salt and their mixture.

6. the process of claim 1 wherein that described rinsing liquid also contains a kind of pH buffer reagent.

7. the method for claim 5, wherein said water-soluble additive is a tripoly phosphate sodium STPP, a kind of buffer reagent that described rinsing liquid is selected from alkaline carbonate, acid carbonate and the silicate of one or more no calcites is buffered to pH greater than 8.0.

8. the method for claim 5, wherein said water-soluble detergent auxiliary comprises Citrate trianion or nitrilotriacetic acid(NTA) salt, and a kind of buffer reagent that described rinsing liquid is selected from alkaline carbonate, orthophosphoric acid salt, acid carbonate and the silicate of one or more no calcites is buffered to pH 〉=5.5.

9. the process of claim 1 wherein that described rinsing liquid also comprises a kind of beneficial agent that is selected from white dyes, spices, starch, lipase, soil release polymer, optical white and bluing agent.

10. the process of claim 1 wherein that described rinsing liquid also comprises a kind of clay.

11. the method for claim 1, it is undertaken by hand washing.

12. a composition of handling washed fabric in rinse cycle, it comprises:

(a) the water-soluble detergent auxiliary of 10-99.95% weight,

(b) the pH buffer reagent of 0-90% weight is 99.9 with (b) weight ratio (a): 0-10: 90 and

(c) white dyes and/or spices, described composition contains＜the non-soap synthetic surfactant of 0.25g/l.

13. the composition of claim 12, said composition also comprise the beneficial agent that is selected from starch, lipase, soil release polymer, optical white and bluing agent of significant quantity.

14. the composition of claim 12 or 13, said composition are in powder composition, particulate state, liquid, paste, gel, strip or flaky form.

15. a laundry detergent product, this product comprises:

(i) first composition, it comprises detergent surfactant, detergent auxiliary and other optional detergent ingredients,

(ii) second composition, it is each a composition among the claim 12-14.

16. the product of claim 15, wherein said first composition (i) is a kind of granular laundry detergent compositions.

17. the product of claim 15 or 16, wherein said first and second compositions are in independent primary package, and another is installed in the common secondary package.