EP1957621B1 - Stability improvement of liquid hypochlorite-containing washing and cleaning compositions - Google Patents

Abstract

The improvement of shelf stability in hypochlorite-containing aqueous liquid washing and/or cleaning agents that contain colored metal pigment is achieved by the use of an alkali iodide and a sterically hindered amine.

Description

The present invention relates to the stabilization of hypochlorite-containing liquid detergents and / or cleaners for hard surfaces in households, for example for cleaning tiles.

Sodium hypochlorite is known to be a highly effective bleaching agent and has been used for a long time, optionally with soaps and / or synthetic surfactants, to remove stains and all sorts of soils from laundry to textiles as well as hard surface cleaning. It is normally sold in concentrations of about 2 to 10% by weight in water for household use. For such preparations, it is not uncommon for them to contain hydrotropes to regulate their viscosity.

Liquid detergent formulations or corresponding preparations of hard surface cleaners containing hypochlorite as a bleach component are susceptible to loss of activity upon prolonged storage, especially because of the then-degradation of the hypochlorite. Among the ingredients that are desirable from an application point of view or for aesthetic reasons in detergents and cleaners include, in addition to the performance of such agents crucial influencing agents, in particular hypochlorite, and colorants, which should give a pleasant visual appearance in particular liquid preparations. In particular, dyes are attacked by hypochlorite usually slightly oxidative, so that the color impression of hypochlorite-containing liquid agent changes rapidly on storage.

Although there are some proposals for stabilizing alkali hypochlorite in aqueous systems, alternative approaches are still desirable.

The European patent application EP 0 903 403 suggests, for example, an alkyl (alkoxy) _n -sulfate (where n = 0.5 to 20), which may contain only small amounts of unsulfated material and very low levels of metal impurities, to increase the chemical stability of liquid bleaches a hypohalite containing.

EP-A1-79102 discloses aqueous hypochlorite solutions containing a halogenated metallophthalocyanine pigment.

EP-A1-565788 describes the stabilization of aqueous hypochlorite solutions by iodate.

Finally disclosed EP-A2-1391501 a method for stabilizing the viscosity and / or the active chlorine content of liquid compositions containing hypochlorite by adding certain hindered amines.

Surprisingly, it has now been found that certain sterically hindered amines have a marked stabilizing effect both on hypochlorite in aqueous liquid detergents and cleaners, as well as on color pigments which are normally rapidly degraded in such agents by the hypochlorite. As a further advantage, it has been observed that a synergistic effect between such sterically hindered amines and alkali iodides results in incorporating larger amounts of dyes into hypochlorite-containing agents than would otherwise be possible.

in der die Reste R¹, R², R³ und R⁴ unabhängig voneinander für Wasserstoff, eine Methylgruppe oder eine Ethylgrupe stehen mit der Maßgabe, dass nicht mehr als 2 von diesen Resten gleichzeitig Wasserstoff sind, und X für Wasserstoff, Sauerstoff, eine Methylgruppe, eine Ethylgrupe, -OH oder -OR⁵ steht, wobei R⁵ eine C_1-4 Alkylgruppe oder eine Cyclohexylgruppe ist, zur Stabilisierung von Hypochlorit-enthaltenden wäßrigen flüssigen Zusammensetzungen, die farbiges Metallpigment enthalten.An object of the invention is therefore the joint use of an alkali metal iodide and a sterically hindered amine which has the group of the general formula (I),

in which the radicals R ¹ , R ² , R ³ and R ⁴ independently of one another are hydrogen, a methyl group or an ethyl group, with the proviso that not more than 2 of these radicals are simultaneously hydrogen, and X is hydrogen, oxygen, a Methyl group, an ethyl group, -OH or -OR ⁵ , wherein R ^{5 is} a C _1-4 alkyl group or a cyclohexyl group, for stabilizing hypochlorite-containing aqueous liquid compositions containing colored metallic pigment.

in der die Reste R¹, R², R³ und R⁴ unabhängig voneinander für Wasserstoff, eine Methylgruppe oder eine Ethylgrupe stehen mit der Maßgabe, dass nicht mehr als 2 von diesen Resten gleichzeitig Wasserstoff sind, und X für Wasserstoff, Sauerstoff, eine Methylgruppe, eine Ethylgrupe, -OH oder -OR⁵ steht, wobei R⁵ eine C_1-4 Alkylgruppe oder eine Cyclohexylgruppe ist, enthält.A second aspect of the invention is an aqueous liquid bleach containing alkali hypochlorite and colored metal pigment characterized by additionally comprising a combination of akaliyodide and hindered amine having the group of general formula (I),

in which the radicals R ¹ , R ² , R ³ and R ⁴ independently of one another are hydrogen, a methyl group or an ethyl group, with the proviso that not more than 2 of these radicals are simultaneously hydrogen, and X is hydrogen, oxygen, a methyl group, an ethyl group, -OH or -OR ^5, where R ⁵ is a C _1-4 alkyl group or a cyclohexyl group, contains.

Among the inventively preferred amines are those in which the group of general formula (I) is part of a piperidine ring. In these, in addition to the substituents R ¹ , R ² , R ³ , R ⁴ and X, the piperidine ring preferably has a substituent in position 4 which is -OH, -NHR ⁶ or oxygen linked via a double bond, where R ^{6 is} a C _1-4 alkyl group or a cyclohexyl group.

Normally, it is sufficient if more than 0 wt.% Up to about 0.1 wt.%, In particular about 0.0005 wt.% Up to not more than about 0.03 wt sterically hindered amine is included in the liquid agent to be stabilized.

In a preferred embodiment, the liquid agent stabilized according to the invention contains from 0.5% to 5% by weight alkali hypochlorite, especially sodium hypochlorite.

Such formulations are particularly suitable and very effective as hard surface cleaners, for example for use on walls, work surfaces, floors and the like. The agents, especially because of their hypochlorite content, are particularly suitable for removing stains such as occur in kitchens or bathrooms, including greasy stains that may occur after using bathtubs, shower cubicles and sinks.

A bleaching agent in the form of hypochlorite is an essential component of the compositions according to the invention. Bleaches per se are well-known components of detergent compositions and are particularly successful in controlling mildew and mildew, soils that are commonly found in soap deposits or in association with them. Although other alkali metal hypochlorites, such as potassium hypochlorite, are useful, it is still preferred to use sodium hypochlorite in stabilized compositions of this invention. Commercially available aqueous sodium hypochlorite solutions often contain considerable amounts of chloride salts. These can readily be used for the production of agents according to the invention, so that it is not necessarily dependent on the use of high-purity NaOCl. In a preferred embodiment of the invention, the compositions contain 0.5% by weight to 4.5% by weight, in particular 1% by weight to 4% by weight, of alkali metal hypochlorite.

Preferably, the agents contain more than 0 wt .-% to 0.01 wt .-%, in particular up to 0.005 wt .-% of colored, especially blue and / or green, metal pigment. Among them, complex compounds of nickel, cobalt, cuprous, iron and / or manganese are preferred; particularly preferred are copper phthalocyanine dyes.

The stability of both the colored metal pigment and the alkali hypochlorite is enhanced by the presence of alkali iodide. Preferably, more than 0 wt% to about 0.01 wt%, more preferably about 0.0005 wt% to about 0.003 wt% alkali iodide, especially potassium iodide is present.

The stabilized agents according to the invention are normally alkaline and may contain for this purpose about 0.1 wt .-% to 2 wt .-%, in particular 0.1 wt .-% to 1.1 wt .-% alkali metal hydroxide. The preferred alkali hydroxide is sodium hydroxide, and also the alkali salts mentioned in connection with the other ingredients of the compositions are preferably the sodium salts.

in der R⁷ eine Alkyl- oder Alkenylgruppe mit 6 bis 22 Kohlenstoffatomen oder eine Gruppe R¹⁰CO-NH-(CH₂)_n- ist, R⁸ Wasserstoff oder eine Alkylgruppe mit 1 bis 4 Kohlenstoffatomen ist, R⁹ Wasserstoff oder eine Alkylgruppe mit 1 bis 4 Kohlenstoffatomen ist, R¹⁰ eine Alkyl- oder Alkenylgruppe mit 6 bis 22 Kohlenstoffatomen ist, m eine Zahl von 1 bis 6 und n eine Zahl von 1 bis 3 ist. Beispiele für besonders geeignete Vertreter dieser Klasse von Tensiden umfassen C_12-18-Alkyl-dimethylbetain, kommerziell erhältlich als Kokosnußbetain, und C_10-16-Alkyl-dimethylbetain, kommerziell erhältlich als Laurylbetain. Eine weitere Klasse besonders bevorzugter Tenside sind die Alkylethersulfate, die durch Umsetzung von Alkoholen (vorzugsweise mit 6 bis 22 Kohlenstoffatomen) mit Alkylenoxiden, insbesondere Ethylenoxid, und anschließende Sulfatierung und Neutralisation erhältlich sind, insbesondere ein mit 2 Equivalenten Ethylenoxid alkoxyliertes C_12-14-Fettalkoholethersulfat. In den Ethersulfaten ist das korrespondierende Kation vorzugsweise Natrium. Tenside sind, falls anwesend, vorzugsweise in Mengen bis zu 5 Gew.-%, insbesondere von 0,01 Gew.-% bis 3 Gew.-% in erfindungsgemäß stabilisierten Mitteln enthalten.The formulations may contain surfactants that are stable in the presence of the hypochlorite. Preference is given to betaines, in particular of the general formula II,

wherein R ^{7 is} an alkyl or alkenyl group having 6 to 22 carbon atoms or a group R ^{10 is} CO-NH- (CH ₂ ) _n -, R ^{8 is} hydrogen or an alkyl group having 1 to 4 carbon atoms, R ^{9 is} hydrogen or an alkyl group having 1 to 4 carbon atoms, R ¹⁰ is an alkyl or alkenyl group having 6 to 22 carbon atoms, m is a number from 1 to 6 and n is a number 1 to 3 Examples of particularly suitable members of this class of surfactants include C _12-18 alkyl dimethyl betaine, commercially available as coconut betaine, and C _10-16 alkyl dimethyl betaine, commercially available as lauryl betaine. Another class of particularly preferred surfactants are the alkyl ether sulfates obtainable by reacting alcohols (preferably having 6 to 22 carbon atoms) with alkylene oxides, especially ethylene oxide, followed by sulfation and neutralization, especially a C _12-14 fatty alcohol ether sulfate alkoxylated with 2 equivalents of ethylene oxide , In the ether sulfates, the corresponding cation is preferably sodium. Surfactants, if present, are preferably contained in amounts of up to 5% by weight, in particular of 0.01% by weight to 3% by weight, of stabilizers in accordance with the invention.

in der R¹¹ Wasserstoff, eine Gruppe -(CH₂)_x(CHCH₃)_y-NH₂->O oder ein Alkalimetall ist, x eine Zahl von 1 bis 4 und y 0 oder 1 ist. Unter den besonders bevorzugten Aminoxidphosphonsäuren ist das Aminoxid auf der Basis der Aminotrimethylenphosphonsäure. Vorzugsweise sind 0,01 Gew.-% bis 2 Gew.-% solcher Sequestriermittel vorhanden.The preparations may additionally comprise sequestering agents, preferably alkylphosphonic acids, and among these in particular those having at least one amine oxide substituent on the alkyl group, referred to herein as amine oxide phosphonic acids, polyacrylic acids and / or polyoxyacids containing phosphono groups, which may also be in the form of their alkali metal salts. The incorporation of such complexing leads surprisingly to a particularly good gloss retention of the treated hard surfaces. This is not observed if instead other complexing agents, for example methylglycinediacetic acid or nitrilotriacetic acid, are used. Amine oxide phosphonic acids are normally prepared by oxidation of aminoalkyl phosphonic acids. They preferably belong to the group of Compounds according to general formula (III),

in which R ^{11 is} hydrogen, a group - (CH ₂ ) _x (CHCH ₃ ) _y -NH ₂ -> O or an alkali metal, x is a number from 1 to 4 and y is 0 or 1. Among the more preferred amine oxide phosphonic acids is the amine oxide based on aminotrimethylene phosphonic acid. Preferably, from 0.01% to 2% by weight of such sequestering agents are present.

In addition to the constituents mentioned, the preparations stabilized according to the invention may contain small amounts of one or more bleach-stable fragrances. The optional perfume component is preferably of higher relative volatility than the ingredients optionally responsible for a bleaching odor.

The stabilized compositions according to the invention can be prepared in a simple manner by mixing the above-mentioned ingredients in the indicated amounts.

Examples

The preparation (I1) according to the invention with a high pigment content and for comparison purposes preparations without amine (C1), without potassium iodide (C2) and without both (C3) were prepared by mixing the ingredients with water. The compositions were composed as follows [wt%]: I1 C1 C2 C3 sodium hypochlorite 4 4 4 4 C _12/14 fatty alcohol 2 EO sulfate, sodium salt 1.2 1.2 1.2 1.2 Amine ^a) 0.01 - 0.01 - potassium iodide 0.001 0.001 - - Cu phthalocyanine 0.005 0.005 0.005 0.005 sodium hydroxide 1 1 1 1 water on 100 on 100 on 100 on 100 ^a) 2,2,6,6-tetramethyl-4-hydroxypiperidine N-oxide

All funds were bottled in plastic bottles and stored for several weeks. In the preparations according to the invention, the hypochlorite content after storage was significantly higher than in the preparations tested for comparison. In addition, the pressure in the bottle of the agent C3 (presumably because of the formation of oxygen) after only 4 days at 60 ° C to about 100 Kp had increased, whereas the pressure in the inventive agent even after a long time was less than 20 Kp.

Claims (11)

1. Combined use of an alkali iodide and of a sterically hindered amine that comprises the group having the general formula (I)

   

   in which the radicals R¹, R², R³, and R⁴, mutually independently, denote hydrogen, a methyl group, or an ethyl group, with the stipulation that no more than two of said radicals are simultaneously hydrogen, and X denotes hydrogen, oxygen, a methyl group, an ethyl group, -OH, or -OR⁵, R⁵ being a C_1-4 alkyl group or a cyclohexyl group, for stabilizing hypochlorite-containing aqueous liquid compositions that contain colored metal pigment.
2. The use according to Claim 1, wherein in the sterically hindered amine, the group of the general formula (I) is part of a piperidine ring.
3. The use according to Claim 2, wherein in the sterically hindered amine, the piperidine ring comprises, in addition to the substituents R¹, R², R³, R⁴, and X, a substituent in position 4 that is -OH, -NHR⁶, or oxygen joined via a double bond, R⁶ being a C_1-4 alkyl group or a cyclohexyl group.
4. The use according to one of Claims 1 to 3, wherein the composition contains more than 0 wt% to 0.01 wt%, in particular 0.0005 wt% to 0.003 wt%, alkali iodide, in particular potassium iodide.
5. The use according to one of Claims 1 to 4, wherein the composition contains more than 0 wt% to 0.1 wt%, in particular 0.0005 wt% to 0.03 wt%, of the sterically hindered amine.
6. The use according to one of Claims 1 to 5, wherein the composition contains more than 0 wt% to 0.01 wt%, in particular up to 0.005 wt%, colored metal pigment.
7. The use according to one of Claims 1 to 6, wherein the metal pigment is a copper phthalocyanine dye.
8. The use according to one of Claims 1 to 7, wherein the composition contains 0.5 wt% to 5 wt% alkali hypochlorite, in particular sodium hypochlorite.
9. The use according to one of Claims 1 to 8, wherein the composition contains up to 5 wt% bleach-stable surfactant, in particular betaine and/or alkyl ether sulfate.
10. The use according to one of Claims 1 to 9, wherein the composition contains 0.01 wt% to 2 wt% alkylphosphonic acid and/or alkylphosphonate, in particular amine oxide phosphonic acid, polyacrylic acid, polyacrylic acid containing phosphono groups, and/or an alkali salt of one, two, or all three of said acids.
11. An aqueous liquid bleaching agent containing alkali hypochlorite and colored metal pigment, wherein it additionally contains a combination of alkali iodide and sterically hindered amine that comprises the group having the general formula (I)

    

    in which the radicals R¹, R², R³, and R⁴, mutually independently, denote hydrogen, a methyl group, or an ethyl group, with the stipulation that no more than two of said radicals are simultaneously hydrogen, and X denotes hydrogen, oxygen, a methyl group, an ethyl group, -OH, or -OR⁵, R⁵ being a C_1-4 alkyl group or a cyclohexyl group.