SK160298A3 - Concentrated alkaline isotropic detergent liquid with bleach - Google Patents

Abstract

A concentrated alkaline isotropic fabric washing liquid detergent composition comprising at least 23 % of surfactants and further comprising at least 0.2 % hydrogen peroxide bleach, the composition is substantially free from hydrotropes which cause the pH to reduce and impair the effectiveness of the composition. Also a concentrated alkaline isotropic fabric washing liquid detergent composition comprising at least 15 % by weight of surfactant further comprises at least 0.2 % by weight hydrogen peroxide bleach and an optical brightener and is also substantially free from hydrotropes. The compositions may be used as a main wash bleaching liquid or a pretreatment liquid and may be activated with a bleach activator.

Description

Concentrated alkaline isotropic detergent liquid with bleach

Technique '

The invention relates to concentrated, alkaline isotropic liquid detergents which are intended for textile washing and which contain a hydrogen peroxide bleach.

BACKGROUND OF THE INVENTION

Concentrated alkaline isotropic liquid detergents used to wash fabrics typically contain any hydrotrope that allows the use of a high level of surfactant without increasing viscosity too much. Typical hydrotropes are sodium xylene sulphate, ethanol and propylene glycol. International application WO 96/30483 discloses compositions comprising an active agent and anionic together with a hydrotrope and a peroxide, in that in the case of a predominant mixture of a nonionic surfactant hydrogen and a characterized nonionic surfactant, the proportion of all surfactants in the composition is greater and in the case of the predominant anionic surfactant, the proportion of all surfactants is greater than 20%. To reduce shipping, it is desirable for the liquid to contain a solution to the problem of constructing stable, concentrated, alkaline isotropic liquid detergents intended for washing fabrics and containing peroxide has been unattainable for many experts in the art for many years.

reagents in the composition and storage cost concentrated peroxide.

Although numerous publications on concentrated alkaline isotropic liquid detergent compositions intended for washing fabrics and containing a hydrotrope can be found, there are indeed very few papers describing compositions without a hydrotrope. Closest to this is probably a composition comprising 15% anionic surfactant (secondary alkyl sulfonate) and 3.75% nonionic surfactant (primary alcohol ethoxylate (7E0)) and described in WO 96/01311. This formulation has a total surfactant level of less than 20%. In addition, the composition does not contain additional ingredients such as an optical brightener, an anti-redeposition agent, or a dye retardant, making the composition unsuitable for use as a practical concentrated alkaline isotropic liquid laundry detergent and containing a bleach-based bleach. hydrogen peroxide.

Thickened peroxide compositions are also known. These include a thickening system to increase the viscosity when the surfactant is present only at a low concentration. A typical example is GB 2255507, which describes a thickened, peroxide-containing composition with less than 10% surfactant. Such compositions are not suitable for use as laundry detergents. They are thickened to achieve the desired result, i. an adhesive which does not flow when applied to a vertical surface. The skilled artisan would not use these thickened compositions without a hydrotrope as the basis for a new recipe

I concentrated detergent for washing textiles.

SUMMARY OF THE INVENTION

We have now found that the presence of a hydrotrope has a significant and very undesirable negative effect on the storage stability of concentrated alkaline isotropic liquid laundry detergents. In particular, this has been found to be a problem with compositions containing high concentrations of surfactant. This is a problem with concentrated liquid detergent formulations since hydrotropes are commonly found in such detergents. In this description, the word concentrated means that the liquid in its undiluted state contains more than 15%, preferably at least 20% and preferably at least 23% of surfactants. Unless otherwise stated, all percentages are by weight.

The present invention describes a concentrated alkaline isotropic liquid laundry detergent composition comprising at least 15% surfactant in total surfactant concentration, at least 0.2% hydrogen peroxide bleach, and finally an optical brightener. The composition is characterized in that it is substantially free of hydrotropes. It is preferred that no hydrotrope is added to the composition even afterwards. It is possible that a substance that may act as a hydrotrope will be present in a small amount (ie up to 2.5%, preferably less than 1.5% and preferably less than 0.5%), possibly due to some The ingredients of the composition contain this substance in the form of a minor component or an impurity. However, it is preferable to avoid such additives because they probably require a compromise with respect to the shelf life of the composition which is otherwise very stable: the loss of efficiency due to the fact that the amount of hydrotrope material is very small can be compensated by acceptable shelf life. By substantially free of hydrotropes, it is understood in this specification that materials which may act as hydrotropes are present in concentrations up to 2.5%, preferably less than 1.5%, and preferably less than 0.5%. Thus, compositions which are substantially free of hydrotropes are within the scope of the present invention.

The total surfactant concentration is preferably at least 20%, preferably at least 23%. Preferably, the composition comprises anionic and nonionic surfactants.

Any peroxide-compatible optical brightener may be used. Good compatibility with peroxide bleach is provided by the optical brightener Tinopal 'CBS-X (distyrylbiphenyl derivative) from Ciba Geigy. Stilbene-based fluorescent agents can also be used as optical brighteners.

A second aspect of the present invention is a concentrated alkaline isotropic liquid laundry detergent composition comprising at least 23% total surfactants selected from the group consisting of anionic and nonionic surfactants and at least 0.2% peroxide bleach in a total surfactant concentration. hydrogen. The composition is characterized in that it is substantially free of hydrotropes. The composition may also comprise an optical brightener as described above.

The nonionic surfactant, if present, preferably constitutes more than 5 wt. of all means. It is preferred that the composition does not contain more than 5% of surfactants that do not meet the pH criteria when tested according to Test A as described below. It is most preferred that surfactants have residual peroxides when tested according to below.

does not contain more than 5% do not meet the criteria of Test A as described

Preferably, the surfactant system is a mixture of anionic and nonionic surfactants, although exclusively nonionic or exclusively anionic systems can also be used. The compositions may contain or be free of a suitable adjuvant (builder).

Preferred anionic surfactants include:

a) secondary alkane sulfonates such as Hostapur SAS 93 (93% active flakes) or Hoechst Marlon PS 65 (n-alkanesulfonate, sodium ^(c i3-i7) ^low-sulfate) available from Huls.

b) linear alkyl ^(C ₁₃ 10_) benzenesulfonic acids such as Marlon AS 3 from Huls.

(c) alkyl ether sulfonates such as ^: Neopon LOS 70 (70% active sodium salt) from Witco; and

d) olefin sulfonates such as Hostapur OS, supplied by Hoechst as a formulation with 40% active ingredients.

Preferred nonionic surfactants include:

e) primary alcohol ethoxylates ⁽ C13-is), ethoxylated with five to nine moles of ethylene oxide, preferably seven moles, such as Synperonic A7 from ICI / Cargo Fleet.

The pH of the composition may range from 7 to 12, preferably about 9.5.

The peroxide is preferably present as dissolved hydrogen peroxide in a concentration by weight in the range of from 0.2 to 15%, preferably from 1 to 8%, preferably about 5%.

The composition may also contain minor components which are commonly added to liquid detergent compositions intended for demanding applications. These ingredients include perfumes, suitably protected enzymes, preservatives for surfactants, thickeners, colorants, builders, anti-redeposition agents, anti-dye transfer agents (preferably polyvinylpyrrolidone, PVP, which simultaneously acts as an anti-redeposition agent, may be used). as a polymer to prevent dye transfer) and other conventional additives.

Preferably, the composition may contain chelating agents (sequestrants). Preferred chelating agents are diethylenetriamine pentamethylene phosphate, sold as Dequest 2066 by Monsanto, either alone or together with 2,2-dipyridylamine (DPA), optionally with 1,2'-diaminocyclohexyl-tetrakismethylene phosphorous acid. Other chelating agents for transition metal ions may also be used in place of or sequentially with these sequestrants.

In a preferred embodiment of the present invention, the composition is activated by a bleach activator such as TAED, which can be contacted with the composition at the time of use using a two-chamber (double bag) delivery system.

According to a third aspect, the alkaline isotropic liquid scouring of fabrics can also be used at specific points on the scouring fabric. In this process, the invention can be a concentrated detergent composition intended for pre-cleaning stains or other before the fabric undergoes stain removal better than known peroxyacid based compositions, and overall efficiency is enhanced by advanced. the surfactant concentration that can be achieved with the compositions of the present invention. The use of a concentrated formulation also has the advantage of lower shipping and packaging costs, which is desirable in terms of environmental protection. The pretreatment method consists in applying the composition of any one of claims 1 to 11 to a selected area of the fabric, leaving the composition in contact with the fabric for a short time, and the pretreatment is typically 1 minute.

followed by washing. Time to 5 minutes, preferably 2

Compatibility of surfactants with peroxide

The following procedure, referred to as Test A, is used to identify suitable surfactants based on pH and peroxide stability data. The test composition is prepared with 20 wt. of the surfactant to be tested, with the exception of Marlinat CM20, which was tested at a concentration of 15% by weight. After chelating with Dequest 2066, hydrogen peroxide is added in an amount sufficient to achieve a concentration of 5 wt. and the pH is adjusted to 9.5 by the addition of a prechelated (pre -vested) base solution. Details of the surfactants tested are shown in Table 1.

Table 1 - Surfactants tested

code surfactant actively agent source Type 1 Active substances, % wt. anionic Al Marlon AS3 Huls alkylbenzenesulfonic acid (linear alkyl, 97 A2 Marlon AS350 Huls ^C ^ 1Q-13, sodium salt of alkylbenzenesulfonic acid (linear alkyl, C _1Q _ ₁₃₎ The sodium secondary 50 A3 Marlon PS65 Huls 65 A4 Hostapur SAS93 Hoechst Alkanesulfonate (C ₁₃ _ ₁₇ ) secondary alkanesulfonate ^ ^C 13-18 ^, alkylsulfate, laurylsulfate 93 A5 and Empicol 0045 Albright 95 sodium A6 Neopon LOS70 Witco alkyl ether sulfate, lauryl ether sulfate sodium 70 A7 Marlinat CM20 Huls alkyl ether-carbo- 90 anthracenecarboxylic acid, C ₁₂ / ^C t4 fatty alcohol polyglycol ether (2E0) carboxylic acid A8 Crodasinic LS30 Croda sarcosinate-RCONCH ₂ (CH ₃ ) COOH, R = alkyl, sodium lauroylsarcosine 30 A9 Adinol CT95 Croda taurate - RCON (CH ₃ ) CH ₂ CH ₂ SO 4 Na, R = alkyl, methyl- 95 sodium cocoyltaurate A10 Hostapur OS Hoechst olefin 40 N e i ó n o é N1 Synperonic ICI primary alcohol ethoxylate 90 ^c 13 ^{// c} 15 Direct alcohol ethoxylate (7EO) N2 Genaminox LA Hoechst amine oxide, lauryldimethylamine oxide 30 A m f o t e r e Pl Dehyton AB30 Henkel betaine - RN (CH ₃ ) ₂ CH ₂ COO, R = alkyl, cocobetaine 30

Based on our experience, we have derived target pH values and peroxide stability. The residual peroxide is determined by titration with a permanganate solution. The surfactant should meet both the target pH and target peroxide stability. Small amounts (preferably < 5%) of surfactant may be used, which does not meet all target requirements, but this is practical only when most surfactants exceed target values with good margin. As will be apparent from the results in Table 2, satisfactory room temperature stability can be achieved, although stability at elevated temperature is reduced. Such surfactants would not be suitable for compositions intended to be stored at temperatures above 30 ° C, a common situation in warm areas.

PH targets:

pH ²⁵ i2 9/0 after 12 weeks at 25 ° C pH ³⁷ 12 - ^7/5 L ° 12 weeks at 37 ° C; ^pH-45 4> 8.0 4 weeks at 45 ° C

Residual peroxide target values:

p _er 25 per ₁₂ > 85 % AFTER 12 weeks at Deň: 18 ° C Per ³⁷ per ₁₂ > 50 % AFTER 12 weeks at 37 “C Per ⁴⁵ 4 > 55 % AFTER 4 weeks] at 45 ’C

The surfactants that passed the pH and peroxide stability tests are listed below (this combination eliminates surfactants whose good peroxide stability is mainly due to a decrease in the pH of the composition). Samples A3 and A4 are worse in terms of pH stability because their pH has increased. In practice, this increase should not be a problem since the benefits of the alkaline composition are maintained.

Table 2 - Test results

surfactant actively agent p _H ²⁵ 12 nH ³ ? pH ₁₂ PH ⁴⁵ 4 Per 25 per ₁₂ ³⁷ per rer ₁₂ Per ⁴⁵ 4 Target values > 9.0 > 7.5 > 8.0 > 85.0 > 50.0 > 55.0 Al 9.7 9.4 9.5 85.0 53.8 56.4 A2 9.3 6.9 6.7 69.2 34.8 43.2 A3 9.9 10,0 9.9 99.2 58.0 55.6 A4 9.9 * 10.1 * 9.6 84.8 * 51.8 * 64.0 ** A5 9.7 9.2 8.4 70.4 25.6 22.2 A6 9.4 7.5 8.2 85.4 56.8 62.2 A7 9.4 7.7 7.3 97.6 82.4 83.8 A8 7.7 7.2 7.0, 75.2 37.4 52.5 A9 6.9 5.7 6.1 84.7 70.2 71.1 A10 76.5 9.6 9.5 9.5 96.5 88.2 NI 9.1 8.2 8.8 90.0 79.6 82,2 N2 8.2 7.5 7.5 90.0 59.0 64.6 PI _Λ ** kk 9.3 8.1 7.5 84.2 0 0.2

Data for 16 weeks Data for 8 weeks Data for 4 weeks

Surfactants sorted by decreasing pH stability:

A1> A4 / A3> N1 / A6

Surfactants sorted by decreasing peroxide stability:

NI> A6> A3> Al

A list of surfactants preferred for both pH and peroxide stability is given above. Secondary alkanesulfonates A3 and A4 are particularly suitable for their combination of pH and epoxide stability. In addition to pH and peroxide stability, appropriate phase behavior is also required. In this regard, we have examined surfactants that meet the stability criteria of pH and peroxides and have obtained the results below using the procedure described as Test B in this specification. Test B consists of measuring the viscosity of a series of surfactant solutions whose concentration increases by 5% each. The concentration above which the viscosity exceeds 1.2 kg.m ^-1 .s ^-1 is referred to herein as the threshold concentration. For the purposes of this test, a value of 1,2 kg.m ^-1 .s ^-1 shall be considered as the upper limit in terms of consumer acceptance. The level at which the surfactant is used in the liquid detergent should be below the threshold concentration, preferably at least 5%, preferably at least 9%. This is to make the reserve for inaccurate t

dosing in commercial production and / or storage evaporation. The results of the determination of the threshold concentrations for the preferred surfactants are given in Table 3. The numbers in parentheses are the viscosity of aqueous solutions of surfactants * -1-1 active agents in kg.m.s ^A at 25 concentrations.

C and 21 sec

Table 3

surfactant actively agent Concentration (% by weight) below which the viscosity is <12 kg.m ^-1 .s ¹ at 25 ° C and 21 s ¹ anionic Al A3 A4 A6 25 (1,165) 35 (0.925) 40 (0.755) 25 (0.014) nonionic N1 25 (0.675)

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described in more detail based on the following non-limiting examples.

Table 4 details the recipe examples. All composition data are weight percent. The compositions contained PVP (polyvinylpyrrolidone) as an anti-redeposition and dye-retardant and TINOPAL CBS-X, an optical brightener from Ciba Geigy. The effect of storage on formulations at various temperatures is shown in Tables 5-9 in the form of pH data and residual peroxide concentration. Since peroxide is more stable under acidic conditions, a favorable peroxide stability often occurs when

However, pH is undesirable because it makes it difficult to activate peroxide with a bleach activator such as TAED.

reduces the detergent effect

Table 4

Ingredient. Example 1 2 3 4 5 Nl 14.0 17.5 7.5 7.5 15.4 Al 6.0 - - - 5.6 A3 - 7.5 17.5 - 7.0 A4 - - - 17.5 - NaOH * 0.77 - - - 0.71 Dequest 2066 0.5 DPA 0.06 PVP 0.5 Tinopal CBS-X 0.2 peroxide . '. . . 5,0, Water up to 100% initial pH 9.50 9.48 9.50 9.51 9.45 viscosity (21 s ^-1 . 0,840 0,280 0,115 0,070 0,370 25 C), kg.m ^-1 .s ¹

Additional NaOH was added to reach the final pH

Table 5 - Example 1

Time in weeks PH Residual peroxide (%) 5 ’C 25 ’C 37 C 45 ’C 5 ’C 25 ’C 37 ’C 45 'C 0 9.50 9.50 9.50 9.50 100 100 100 100 1 9.39 9.25 9.22 9.16 - - - - 2 9.63 9.37 9.37 9.24 100 99.59 96,69 96 48 4 9.34 9.22 9.19 8.98 - - - - 8 9.37 9.07 8.92 7.21 100 97.52 88.61 82. 61 12 9.43 9.13 8.73 7.0 100 94,21 84.89 77, 64 16 9.30 9.13 7.77 6.50 100 94.20 84,88 81. 98 24 9.47 9.03 7.47 6.05 100 92.55 78.70 75. 80

Table 6 - Example 2

Time in weeks PH Residual peroxide (%) 5 ’C 25 ’C 37 ’C 45 ’C 5 ’C 25 ’C 37’ C 45 ’C 0 9.48 9.48 9.48 9.48 100 100 100 100 1 9.36 9.44 9.32 9.42 100 100 1 99.60. 98.60 2 9.54 9.16 9.14 9.14 100 100 97.60 95,19 4 9.44 9.08 9.03 7.35 100 100 95.79 89.38 8 9.35 8.87 8.14 6.86 97 100 92.86 88.17 12 9.52 9.03 7.52 6.50 100 100 90.60 92.60

Table 7 - Example 3

Time in weeks PH Residual peroxide (%) 5 ’C 25 C 37 ’C Deň: 32 ° C 5 ’C 25 ’C 37 ’C 45 'C 0 9.50 9.50 9.50 9.50 100 100 100 100 1 9.40 9.65 9.32 9.30 98.80 99.60 98.60 100 2 9.61 9.47 9.51 9.38 100 98,00 96,60 91 38 4 9.46 9.37 9.38 8.88 100 99.00 87.20 79. 36 8 9.31 9.15 9.05 6.99 100 95 82,17 70 94 12 9.55 9.35 9.15 6.85 100 96.2 80.6 71. 70

Table 8 - Example 4

Time in weeks PH Residual peroxide (%) 5 ’C 25 ’C 37 ’C 45 ’C 5 ’C 25 ’C 37 ’C 45 'C 0 9.51 9.51 9.51 9.51 100 100 100 100 1 9.57 9.55 9.56 9.62 100 100 98.97 92 61 2 9.86 9.67 9.74 9.78 100 100 96.72 85. 42 4 9.61 9.55 9.47 9.35 100 98.56 78.03 73. 10 8 9.68 9.57 9.44 7.80 98,15 96.72 75.16 59, 10 12 9.88 9.59 9.37 7.00 100 98,15 73.70 55. 10

Table 9 - Example 5

Time y weeks pH Residual peroxide (%) 5 ’C 25 ’C 37 ’C 45 ’C 5 ’C Deň: 18 ° C Deň: 32 ° C 45 'C 0 9.45 9.45 9.45 9.45 100 100 100 100 1 9.53 9.49 9.42 9.39 100 100 95.42 92 03 2 9.58 9.50 9.40 9.31 99.4 98.41 95.62 91 44 4 9.62 9.46 9.32 8.16 100 99.0 91.24 81. 08 8 9.80 9.63 9.05 6.99 100 100 86.70 78. 50

I

Claims (9)

- 17 PATENT CLAIMS A concentrated alkaline isotropic liquid laundry detergent composition comprising at least 15 wt. % surfactant, further at least 0.2 wt. hydrogen peroxide bleaches; and an optical brightener, wherein the composition is substantially free of hydrotropes. Composition according to claim 1, characterized in that it contains at least 20 wt. surfactant. 3. A concentrated alkaline isotropic liquid laundry detergent composition comprising at least 23 wt. % surfactant and at least 0.2 wt. a hydrogen peroxide bleach, characterized in that the composition is substantially free of hydrotropes as defined above. Composition according to any one of the preceding claims, characterized in that the surfactant comprises anionic and nonionic surfactant. Composition according to any one of the preceding claims, characterized in that it further comprises an anti-redeposition agent. 6. A composition according to any preceding claim, further comprising a dye transfer agent. Composition according to any one of claims 4 to 6, characterized in that the nonionic surfactant constitutes more than 5% by weight. from the whole device. Composition according to claim 7, characterized in that it contains at most 5% by weight of the composition. a surfactant which does not reach the target pH in Test A described herein. Composition according to claim 8, characterized in that it contains at most 5 wt. it does not reach the residual peroxide concentration at the surface described herein. of the active agent that test A target value