WO1990006354A1

WO1990006354A1 - Process for washing textiles prone to fading

Info

Publication number: WO1990006354A1
Application number: PCT/EP1989/001402
Authority: WO
Inventors: Winfried Pochandke; Rolf Puchta; Rudolf Weber; Heinz-Manfred Wilsberg; Maria Liphard
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 1988-11-28
Filing date: 1989-11-20
Publication date: 1990-06-14
Also published as: EP0372291A1; DE3840056A1

Abstract

Textiles prone to fading can be washed without fading in aqueous washing lyes containing anionic tensides and non-ionic tensides with an HLB value greater than 11 as well as water-soluble polymers which inhibit fading. To this end, the ratio of non-ionic to anionic tensides in the washing lye is adjusted so as to lie in the range 1:0.3 to 1:3, preferably 1:0.5 to 1:2. This ratio is obtained for example by adding suitable quantities of a washing additive containing non-ionic tensides and, if necessary, water-soluble polymers, to washing lyes containing anionic tensides.

Description

"Process for washing discolouration-sensitive textiles"

The present invention relates to a washing process which counteracts the dye and brightener transfer from colored or lightened textiles to white or light-colored or unlightened textiles during the washing together.

The transfer of dyes, to which the brighteners are also to be counted, when washing colored and white or light-colored textiles together has been a problem which has been known for a long time and for which there have already been some proposed solutions. From DE-B-22 32 353 a detergent is known, the discoloration-inhibiting additive are polymer components based on polyvinylpyrrolidone. DE-A-29 16 656 describes detergents with an addition of cationic alkylpyrridinium salts to prevent the transfer of optical brighteners from brightener-containing laundry items to brightener-free laundry items during washing. From DE-B-12 24 698 it is known that by treating textiles which have undergone a color shift due to brightener transfer, solutions of tertiary and quaternary organic nitrogen bases or their salts can bring about a color regeneration. DE-A-35 19 012 relates to detergents containing polymer constituents based on polyvinylpyrrolidone and water-soluble cationic compounds. DE-A-28 14287 is polyvinylimidazole as the discoloration-inhibiting active ingredient and DE-A-28 14 329 Polyvinyloxazolidone known. EP-A-0 262 897 describes detergents based on anionic surface-active compounds, polyvinylpyrrolidone and nonionic compounds with an HLB value of not more than 10.5. The last-mentioned prior art document shows that the discoloration-inhibiting action of the water-soluble polymers mentioned is not impaired by anionic surfactants if nonionic surfactants with a low HLB value are used at the same time. Until then, experts had assumed that the effectiveness of the discoloration-inhibiting water-soluble polymers was linked to the complete or extensive absence of anionic surfactants (cf. DE-B-22 32 353). It can be seen from the prior art that the effectiveness of water-soluble polymers as a discoloration-inhibiting active ingredient is linked either to the absence of anionic surfactants or, if anionic surfactants are used, to the use of nonionic surfactants with a low HLB value. Nonionic surfactants with a high HLB value are, however, interesting wash-active compounds.

The object of the present invention is therefore to utilize nonionic surfactants with a high HLB value for washing discoloration-sensitive textiles in the presence of anionic surfactants and discoloration inhibitors.

It has now surprisingly been found that nonionic surfactants with a high HLB value can be used as a discoloration inhibitor in the presence of anionic surfactants and water-soluble polymers if one maintains certain proportions of anionic surfactants and nonionic surfactants with a high HLB value during washing . Subject of the present The invention is therefore a process for washing textiles which are sensitive to discoloration in aqueous wash liquors and which contain anionic surfactants, nonionic surfactants and water-soluble polymers as a discoloration inhibitor. The process is characterized in that the weight ratio of nonionic surfactants to anionic surfactants in the wash liquor is set in the range from 1: 0.3 to 1: 3 and the HLB value of the nonionic surfactants is greater than 11.

Discoloration-sensitive textiles in the sense of the present invention are those white or light-colored textiles which undergo a change in color when washed together with colored or heat-containing textiles.

Suitable anionic surfactants are water-soluble alkali salts of organic sulfates and sulfonates with alkyl groups which contain 8 to 22 carbon atoms. Examples of suitable anionic surfactants are sodium or potassium salts of alkyl sulfates, in particular alkyl sulfates which are derived from CQ to C g alcohols, for example tallow alcohol or coconut alcohol. Other suitable anionic surfactants are the sodium or potassium salts of Cg to C20- ^A ^ yl-benzenesulfonates, in particular those alkylbenzenesulfonates whose alkyl group contains 10 to 15 carbon atoms. Other anionic surfactants that can be used in the washing process according to the invention are sodium or potassium salts of fatty acids with 10 to 22 carbon atoms. These soaps are taken into account in the calculation when setting the ratio of nonionic surfactants to anionic surfactants by the process according to the invention. Nonionic surfactants which are used in the process according to the invention have an HLB value of more than 11. The HLB value indicates the ratio of the hydrophilic to the hydrophobic part of the molecular weight of the nonionic surfactants. The HLB value can easily be determined or calculated, especially for adducts of ethylene oxide with longer-chain alcohols. Methods of determination and calculation are known in the literature, for example from MJ Schick "Noπioπic Surfactants", Dekker, New York, 1967. Longer-chain alcohols are linear or branched, saturated or unsaturated alcohols with at least 10 carbon atoms in the molecule or mixtures of such alcohols. Particularly suitable nonionic surfactants are adducts of ethylene oxide with such alcohols. Addition products of ethylene oxide and propylene oxide onto such alcohols are also suitable nonionic surfactants, provided that their HLB value is greater than 11. The alcohols can be derived from natural fats or oils, for example from coconut oil or taig fat. They then have 10 to 22 carbon atoms in the molecule and are predominantly linear. Synthetically produced alcohols are, for example, oxo alcohols with 12 to 18 carbon atoms in the molecule. Addition products of ethylene oxide or ethylene oxide and propylene oxide onto such alcohols are likewise suitable nonionic surfactants, addition products of ethylene oxide onto such alcohols being preferred. Mixtures of nonionic surfactants, some of which have an HLB of 11 or less, can also be used; in that case it is important for the implementation of the method according to the invention that the mixture of nonionic surfactants is composed such that the HLB value of the mixture is greater than 11.

It is of particular advantage for the process according to the invention if the weight ratio of nonionic surfactants to anionic surfactants in the wash liquor in the range of 1: 0.5 to 1: 2. Universal detergents generally have such a ratio of anionic surfactants to nonionic surfactants. In order to be able to wash textiles susceptible to discoloration without discolouration, it is therefore only necessary to add the water-soluble polymers mentioned to the universal detergents as a discoloration inhibitor. In contrast, mild detergents contain nonionic and anionic surfactants in a ratio that is outside the stated range. When using detergents of this type, it is therefore necessary to add not only the abovementioned water-soluble polymers as a discoloration inhibitor, but also so much nonionic surfactants with an HLB value which is greater than 1 l, to wash discoloration-sensitive textiles that the ratio of nonionic surfactants to anionic surfactants in the wash liquor is in the range specified for the process according to the invention.

For carrying out the process according to the invention, it is advantageous that the concentration of the anionic surfactants in the wash liquor is in the range from 0.1 g / 1 to 3 g / 1, preferably in the range from 0.5 g / 1 up to 1.5 g / 1. With a concentration of anionic surfactants in this area, you not only get particularly good washing results but also a particularly low level of discoloration of the discoloration-sensitive textiles.

A further criterion for a preferred embodiment of the method according to the invention is the concentration of the nonionic surfactants in the wash liquor. In a preferred embodiment, the concentration of the nonionic mentioned is Surfactants with an HLB value of more than 11 in the wash liquor 0.1 g / 1 to 3 g / 1, preferably 0.5 g / 1 to 1.5 g / 1.

A further preferred embodiment of the method according to the invention takes into account the concentration of the water-soluble polymers used as the discoloration inhibitor in the wash liquor. The concentration of the water-soluble polymers in the wash liquor is preferably set in the range from 0.01 g / 1 to 0.5 g / 1, in particular in the range from 0.02 g / 1 to 0.3 g / 1.

The water-soluble polymers used as discoloration inhibitors are the already above-mentioned active ingredients polyvinylimidazole and ^"D olyviπyloxazo1idon and copolymers based on N-vinylimidazole or N-vinyloxazolidone with N-Viπylpyrrolidon in which the proportion of N-vinylpyrrolidone accounts for at least 50 wt .-% and in particular ¬ special polymers based on N-vinylpyrrolidone. Such a polymer component can have a molecular weight in the range of about 10,000 to 1,000,000. Suitable homopolymers have a molecular weight between about 15,000 to about 700,000. In copolymers which are suitable for the washing process according to the invention, the proportion of N-vinylpyrrolidone is at least about 50% by weight of the copolymer. Suitable comonomers are, for example, acrylonitrile and maleic anhydride. The preferred molecular weight of suitable copolymers is in the range from about 20,000 to about 200,000. Particularly effective homopolymers have, for example, a molecular weight in the range from 30,000 to 600,000, in particular approximately 40,000.

Of particular value for the process according to the invention are nonionic surfactants with an HLB value between 11.5 and 15. The use of such surfactants is therefore preferred. Preferably are used as nonionic surfactants with an HLB value of more than 11 addition products of ethylene oxide onto linear or branched, saturated or unsaturated alcohols with at least 10 carbon atoms in the molecule and in particular mixtures of such addition products. Such mixtures are usually present anyway in the production of the nonionic surfactants from natural fats or oils or from synthetically produced alcohols. The number of carbon atoms for the production of nonionic surfactants from suitable alcohol mixtures is in the range from 10 to 20 carbon atoms in the molecule. The amount of ethylene oxide or ethylene oxide and propylene oxide to be added thereon depends on the requirement of an HLB value of more than 11, ie nonionic surfactants from longer-chain alcohols require a larger amount of added ethylene oxide to achieve an HLB value of more than 11 or Ethylene oxide and propylene oxide as shorter-chain alcohols.

The weight ratios and concentrations which are essential for carrying out the process according to the invention can be adjusted by adding as much detergent-inhibiting water-soluble polymers to the wash liquor and, if necessary, nonionic surfactants with an HLB value of more than 11 that the concentration or quantity ratios mentioned are obtained in the wash liquor. A further possibility for carrying out the process according to the invention is to use detergents of corresponding composition in a concentration in the wash liquor which corresponds to the concentration data given for carrying out the process according to the invention.

The present invention furthermore relates to a detergent additive containing nonionic surfactants which have an HLB value of more than 11 and, if necessary with a content of water-soluble polymers which act as a discoloration inhibitor, in such proportions that this detergent additive can be added to detergents or wash liquors containing anionic surfactants in which the detergents used to carry out the process according to the invention essential concentration and quantity ratios are not available, the required quantity and concentration ratios in the wash liquor can set. In many cases it is advantageous that the detergent additive contains further additional detergent constituents, for example builders, such as phosphates, zeolite A, layered silicates, sodium carbonate, water glass, complexing agents such as phosphonates or aminopolycarboxylic acids, carriers such as sodium chloride or sulfate, urea, oxygen carriers such as perborate or carbonate, activators for perverbiπdungen such as tetraacetylethylene diamine, enzymes, fragrances, dyes or for liquid compositions, solvents and hydrotropes. In addition, it can also contain confectioning aids, for example fillers or carriers, which in turn can be detergent constituents but need not be. The advantage of such a detergent additive is that commercially available detergents, with which it is generally impossible to wash textiles susceptible to discoloration without discoloration, can be improved to such an extent with regard to their dye-inhibiting properties that textiles sensitive to discoloration can be used with or without negatives noticeable discoloration can be washed together with discolouring textiles.

The invention is illustrated by the following examples. Examples

example 1

A commercially available mild detergent with a ratio of nonionic surfactant to anionic surfactant (HLB value greater than 11) of 1: 6.5 was at 60 ° C (in the single-solution washing process for washing white cotton textiles and colored laundry with the addition of a Sirius light red F4BL dyed test fabric, which tends to give off dye very strongly, the detergent contained no discoloration-inhibiting additive. The extent of the discoloration of the white textiles was determined by determining the "color difference" in •%, based on dE max ¬ method is described in the magazine "defazet", 31st year (1977), number 8, pages 318 to 324. Low values mean strong discoloration, 100% mean no discoloration. The result for this detergent is listed in Table I under la In a further test of the wash liquor, 0.05 g of polyvinylpyrrolidone (PVP) with an average molewi was used per liter of wash liquor In addition to 40,000, the color difference improved in accordance with the information in Table I, Experiment Ib. In a further experiment, in addition to 0.05 g of PVP, 0.5 g of an oxoalcohol ethoxylate with an HLB value of 12 was added per liter of wash liquor, so that the ratio of nonionic surfactant to anionic surfactant ( HLB value greater than 11) was shifted to 1: 1.15, the color difference improved to the value listed in Table I under lc. With a further addition of non-ionic surfactant beyond the claimed lower limit, the color difference deteriorated again. Example 2

In the same way as described in Example 1, a commercial heavy-duty detergent was used for washing. The detergent had a ratio of nonionic surfactant (HLB value ^• over 11) to anionic surfactant of 1: 5.9. The result for its tendency to discolouration is listed in Table I under 2a. By adding 0.05 g of PVP per liter of wash liquor, the color difference increases to the value listed under 2b in Table I. However, an additional 0.5 g per liter of wash liquor of a nonionic surfactant (as in Example 1) was added, so that the ratio of nonionic surfactants to anionic surfactants was shifted to a value of 1: 1.4, improved the color difference continues to the value listed under 2c. With a further addition of nonionic surfactant beyond the claimed lower limit, the color difference deteriorated again. Similar results were obtained when using discoloration inhibitors based on polyvinylidazole and polyvinyloxazolidone.

It can thus be seen from the examples that, with a very specific, narrow ratio of certain nonionic surfactants to anionic surfactants, the discoloration-inhibiting effect of certain water-soluble polymers reaches a maximum.

Table I

Claims

1. A process for washing discoloration-sensitive textiles in aqueous wash liquors which contain anionic surfactants, nonionic surfactants and water-soluble polymers as a discoloration inhibitor, characterized in that the weight ratio of nonionic surfactants to anionic surfactants in the wash liquor is in the range from 1: 0. 3 to 1: 3, preferably in the range from 1: 0.5 to 1: 2, and the HLB value of the nonionic surfactants is greater than 11.

2. The method according to claim 1, characterized in that the concentration of the anionic surfactants in the wash liquor in the range from 0.1 g / 1 to 3 g / 1, preferably in the range from 0.5 g / 1 to 1.5 g / 1.

3. The method according to claim 1 or 2, characterized in that the concentration of the nonionic surfactants in the wash liquor in the range of 0.1 g / 1 to 3 g / 1, preferably in the range of 0.5 g / 1 to 1, 5 g / 1.

4. The method according to any one of claims 1 to 3, characterized gekenn¬ characterized in that the concentration of water-soluble poly mers in the wash liquor in the range of 0.01 g / 1 to 0.5 g / 1, preferably in the range of 0 .02 g / 1 to 0.3 g / 1.

5. The method according to any one of claims 1 to 4, characterized gekenn¬ characterized in that as water-soluble polymers, homo- or copolymers based on N-vinylimidazole, N-vinyloxazolidone or in particular N-vinylpyrrolidone or a mixture of these polymers used.

6. The method according to any one of claims 1 to 5, characterized gekenn¬ characterized in that nonionic surfactants with an HLB value between 11.5 and 15 are used.

7. The method according to any one of claims 1 to 6, characterized gekenn¬ characterized in that as nonionic surfactants Anlagungs¬ products of ethylene oxide to linear or branched, saturated or unsaturated alcohols with at least 10 carbon atoms in the molecule and in particular mixtures of such adducts used.

8. Detergent additive with a content of nonionic surfactants, which have an HLB value of more than 11, and, if necessary, with a content of water-soluble polymers in such proportions that the amounts can be added to detergents or detergents containing anionic surfactants - and concentration ratios according to one of claims 1 to 4 in the wash liquor.

9. Detergent additive according to claim 8, characterized in that it additionally contains further detergent components.