SK69999A3 - Aqueous liquid bleaching mixture and method for bleaching dirty substrate - Google Patents

Abstract

The invention provides a bleaching composition of pH 10-14 which comprises an oxygen transfer agent and hydrogen peroxide. It is believed that the reaction of hydrogen peroxide with the imine quat. oxygen transfer agents proceeds through a different route than that of the organic and inorganic peroxides. As a consequence, the formation of acyl hydroxamate is significantly reduced. Furthermore it is believed that when hydrogen peroxide is used as the bleaching agent in the pH range indicated, a surprising improvement in the efficacy of the bleaching system occurs and it is possible to formulate peroxide based systems which have efficacy approaching or exceeding that of hypochlorite without the disadvantages associated with hypochlorite. A further aspect of the present invention provides a method for bleaching a stained substrate which comprises the step of treating the substrate with a bleaching composition of pH 10-14, which bleaching composition comprises an oxygen transfer agent and hydrogen peroxide.

Description

Aqueous liquid bleaching composition and process for bleaching a soiled substrate

Technical field

The invention relates to aqueous liquid bleaching compositions containing hydrogen peroxide and to a method for bleaching a soiled substrate.

BACKGROUND OF THE INVENTION

In household cleaning, fabric washing and many other areas, there is a general need for agents that can 'bleach' contaminated materials, i. that can react with these materials and bleach them. One of the best known of such bleaching agents is sodium hypochlorite, which is widely used in detergent compositions to decolour soils, to contribute to cleaning through its soiling reaction and to kill microorganisms.

Sodium hypochlorite is a strong oxidizing agent that can bleach a very large number of stained substances found in a contaminant, but which has significant limitations when used to bleach certain fatty and pyrolyzed contaminants. Many consumers prefer not to use chlorine-based bleaching agents because of their characteristic and irritating odor of chlorine. Under certain conditions, the use of chlorine-containing bleaching compositions should be avoided because of the possible adverse effects of mixing such compositions with acidic cleaners for the bathroom and the resulting release of chlorine gas.

There is a need for an alternative to chlorine-based bleaching agents and bleaching / cleaning agents. One well known class of alternative agents is peroxide agents. These substances have been widely used as bleaching and cleaning agents, the effectiveness of peroxide substances as bleaching agents is less than that of hypochlorite. There is therefore a general need to find new alternatives to chlorine-based bleaching agents and to improve the properties of these bleaching agents towards those of hypochlorite.

It is known to use oxygen transfer agents such as quaternary

-2minine salts, to increase the whitening activity of peroxide substances. In the context of the present invention, the oxygen transfer agent is a substance that reacts with a peroxide agent, such as hydrogen peroxide to form an oxidative bleaching agent, which oxidative bleaching agent subsequently reacts with the substrate to regenerate the oxygen transfer agent.

Such oxygen transfer agents include the N-methyl-3,4-dihydroisoquinoline salts. US 5360569 discloses that quaternary imine salt molecules can be used to enhance the activity of TAED / perborate bleaching compositions. These systems are believed to work by generating peroxoacetic acid in situ. This organic peroxide is believed to react with the quaternary imine salt to induce bleaching activity. US 5360568 discloses that quaternary imine salt molecules can be used to enhance the activity of monoperoxosulfate (an inorganic peroxide substance) and peroxo-adipyl-phthalimide (PAP) (organic peroxyacid).

It is believed that in said compositions, the quaternary imine salt is converted by reaction with a peracid to an oxaziradinium salt, which may act as an oxygen donor (i.e., a bleaching agent), and which is converted back to the quaternary imine salt. However, the oxaziradinium ion is unstable at the high pH in the compositions described above, and is believed to be converted to the acyl hydroxamate, preventing the bleaching cycle from working effectively. As a result, these compositions have a limited pH range and have proven difficult to prepare compositions that are effective against more resistant stains, especially hydrophobic and / or pyrolyzed stains.

It is believed that the above problem is overcome by using hydrogen peroxide as the source of oxidizing equivalents rather than by using organic peroxyacid or inorganic peroxide. This allows the preparation of bleaching compositions at relatively high pHs, with some of the more difficult stains being soluble and thus available for the formulation. Other hitherto unsuspected advantages arise from the use of hydrogen peroxide as described below.

3. Summary of the Invention

The present invention provides an aqueous liquid bleaching composition having a pH of 10 to 14 comprising an oxygen transfer agent and hydrogen peroxide.

Without wishing to limit the scope of this document by referring to any theory of operation, it is believed that the reaction of hydrogen peroxide with the imine quaternary oxygen transfer agent proceeds in a different way than the reaction of the organic and inorganic peroxides mentioned above. As a result, the formation of acyl hydroxamate is significantly reduced. It is further contemplated that when hydrogen peroxide is used as the bleaching agent in the indicated pH range, there is an improvement in the performance of the bleaching system and peroxide-based systems can be prepared that have efficacy at or above hypochlorite without the disadvantages associated with hypochlorite.

Another embodiment of the present invention is a method of bleaching a soiled substrate comprising the step of treating the substrate with an aqueous liquid bleaching composition at a pH of 10 to 14, the bleaching composition comprising an oxygen transfer agent and hydrogen peroxide.

As mentioned above, hydrogen peroxide is an essential component of the compositions of the present invention. Since hydrogen peroxide is a reactive substance, this imposes some limitations on other ingredients that may be present in this mixture. These components are described in more detail below.

Hydrogen peroxide is preferably present at a level of 0.5 to 10% by weight of the product, more preferably 1 to 5% by weight of the product. In typical embodiments of the invention, the weight ratio of hydrogen peroxide to oxygen transfer agent falls within the range of 5: 1 to 20: 1.

Oxygen transfer agents

Oxygen transfer agents used in the present invention include, but are not limited to, quaternary imine salts - N-methyl-3,4-dihydroisoquinolinium salts. When used, suitable counterions include halides, sulfates, methyl sulfates, sulfonates, p-toluenesulfonate, and phosphate. Transfer agents are preferred

-4-oxygen containing a quaternary nitrogen atom.

A wide variety of oxygen transfer agents suitable for use in embodiments of the present invention are ion-containing substances of general structure:

(R ¹ ) (R ² ) C = N ⁺ (R ³ ) (R ⁴ ) where:

R ¹ and R ⁴ are in cis relationship and are substituted or unsubstituted groups selected from the group consisting of hydrogen, phenyl, aryl, heterocyclic ring, alkyl and cycloalkyl radicals:

R ² is a substituted or unsubstituted group selected from the group consisting of hydrogen, phenyl, aryl, heterocyclic ring, alkyl, cycloalkyl, nitro, halogen, cyano, alkoxy, keto, carboxylic acid and carboalkoxy groups:

R ³ is a substituted or unsubstituted group selected from the group consisting of hydrogen, phenyl, aryl, heterocyclic ring, alkyl, cycloalkyl, nitro, halogen and cyano:

Preferably R ¹ , R ² and R ³ together form a group selected from the group consisting of cycloalkyl, polycyclo, heterocyclic and aromatic ring system.

The heterocyclic rings of this specification include the cycloaliphatic and cycloaromatic type of radicals incorporating an oxygen, sulfur and / or nitrogen atom in the ring system. Representative nitrogen heterocycles include pyridine, pyrrole, imidazole, triazole, tetrazole, morpholine, pyrrolidone, piperidene and piperazine. Suitable oxygen heterocycles include furan, tetrahydrofuran and dioxane. Sulfur heterocycles may include thiophene and tetrahydrothiophene

The term substituted as used in relation to R ¹ , R ² , R ³ and R ⁴ includes a substituent which is nitro, halogen, cyano, C 1 -C 20 -alkyl, amino, aminoalkyl, thioalkyl, sulfoalkyl, carboxyester, hydroxyl, C 1 -C 20 alkoxy, polyalkoxy, or C 1 -C 40 quaternary di- or tri-alkyl ammonium.

Preferred oxygen transfer agents are quaternary imine salts, especially those disclosed in US Patent 5,360,568 (Madison and Coope), more particularly substituted

-5 or unsubstituted isoquinolinium salts, preferably 3,4-dihydroisoquinolinium salts, and more preferably N-methyl-3,4-dihydroisoquinolinium salts. N-methyl-3,4-dihydro-isoquinolinium p-toluenesulfonate is a particularly preferred oxygen transfer agent.

Typically, oxygen transfer agents are present at a level of 0.001 to 10% by weight of the product. Preferably, oxygen transfer agents are present at a level of 0.01 to 1% by weight of the product, more preferably 0.1 to 0.5% by weight of the product.

Surfactants

It is preferred that the compositions of the present invention further comprise one or more surfactants. The surfactants may be non-ionic, anionic, cationic, amphoteric or zwitterionic, provided that these, and where necessary their counterions, do not react significantly with the oxygen transfer agent or hydrogen peroxide.

Suitable nonionic detergent actives can be broadly described as being produced by the condensation of alkylene oxide groups that are hydrophilic in nature with an organic hydrophobic substance that may be aliphatic or alkylaromatic in nature. The length of the hydrophilic or polyoxyalkylene radical which is condensed with some particular hydrophobic group can be readily adjusted to provide a water soluble substance having the desired degree of equilibrium between hydrophilic and hydrophobic elements.

Specific examples include the condensation product of aliphatic alcohols having from 8 to 22 carbon atoms in a straight or branched chain configuration with ethylene oxide, such as a coconut oil-ethylene oxide condensate having from 3 to 10 moles of ethylene oxide per mole of coconut alcohol; condensates of alkylphenols whose alkyl group contains from 6 to 12 carbon atoms from 3 to 10 moles of ethylene oxide per mole of alkylphenol.

Preferred alkoxylated alcohol nonionic surfactants are ethoxylated alcohols having a chain length of C9-C11 and an EQ value of at least 3 but less than 10. Particularly preferred nonionic surfactants include C ₁₀ alcohol condensation products with 3 to 8 moles of ethylene oxide. preferred

6-ethoxylated alcohols have a HLB of 10 to 16 calculated. An example of a suitable surfactant is ΝΤΙΝΕΝΤΙΝ 91-35 OFA ”(TM, ex. Kolb AG) Ο ₉ . _η alcohol with five moles of ethoxylation.

Alternative surfactants include amino oxides, amines and / or ethoxylates thereof. C12 to C14 carbon chain length amine oxides are particularly preferred.

If present, the amount of nonionic detergent active used in the composition of the invention will generally be from 0.01 to 30% by weight, preferably from 0.1 to 20% by weight, and most preferably from 3 to 10% by weight for non-concentrated products. The concentrated products will have 10-20% by weight nonionic surfactant, while the diluted sprayable products will have 0.1-5% by weight nonionic surfactant.

pH

As mentioned above, the pH of the composition of the present invention falls within the range of 10 to 14. The pH of the compositions is preferably 10 to 12, more preferably 10 to 11. At these high pH values, we have found that the composition more readily penetrates into contamination.

As mentioned in the illustrative examples below, the use of oxygen transfer agents at high pH is counter-indicated by their tendency to increase the stain color rather than reduce it.

Minority ingredients

Minor ingredients of the compositions of the present invention include those typically present in cleaning compositions.

In compositions containing hydrogen peroxide, it is useful if they include a metal ion complexing agent to retard the decomposition of peroxide by metal ions that may be present as contaminants or if, for example, they are introduced during processing. Again, these components should be selected such that they do not react significantly with the oxygen transfer agent or hydrogen peroxide.

Preferably, the cleaning and / or disinfecting compositions of the present invention will be

-7 further include metal ion sequestrants such as ethylene diamine tetraacetates, amino polyphosphonates (such as DEQUEST (TM) sequestrants) and phosphates, and optionally a wide range of other polyfunctional organic acids and salts may also be used. Preferred metal ion sequestrants are selected from dipicolinic acid, ethylenediaminetetraacetic acid (EDTA) and its salts, hydroxyethylidene diphosphonic acid (Dequest 2010, RTM), ethylenediaminetetra (methylenephosphonic acid) (Dequest 2040, RTM) diethylenepentene (20) , RTM), amino-tri (methylenephosphonic acid) (Dequest 2000, RTM). Phosphonic acid derivatives are particularly preferred. It is preferred that the level of the phosphonic acid derivative metal complexing agent falls within the range of 0.05 to 5% by weight.

Preferably, the cleaning and / or disinfecting compositions of the present invention will further comprise at least 1% by weight of a solvent of form R ¹ -O- (EO) _m - (PO) _n -R ² , wherein R ¹ and R ² are independently C 2-6 alkyl or H but are not both hydrogen and m and are independently 0 to 5. More preferably the solvent is selected from the group consisting of diethylene glycol mono-n-butyl ether, mono-ethylene glycol mono-n-butyl ether, propylene glycol n-butyl ether, isopropanol, ethanol, butanol and mixtures thereof. Typically, the level of solvent in the cleaning and disinfecting compositions is 1 to 10% by weight, with a solvent: nonionic surfactant ratio of 1: 3 to 3: 1, which is particularly preferred.

When the compositions of the invention are liquid, they can be water-thin or thickened. Thickened compositions are advantageous in that they adhere to sloping surfaces and have found particular use as toilet cleaners. Slightly thickened compositions are required for spray application applications, as this reduces the extent to which small droplets may form that could otherwise cause respiratory irritation to the user. Suitable thickeners include amine oxide and soap and nonionic surfactant based systems.

The compositions of the invention may also contain, in addition to the ingredients already mentioned, various other optional ingredients such as colorants, optical brighteners, soil suspending agents, cleaning enzymes, gel control agents, anti-freezing stabilizers, bactericides, perfumes and opacifiers.

Particularly preferred compositions of the invention include a bleaching composition which:

-8 has a pH of 10 to 12, this mixture being an aqueous liquid and containing:

(a) hydrogen peroxide at a level of 0,5 to 10% by weight of the product,

(b) 0.001 to 10% by weight of the isoquinoline salt product;

(c) 0.01 to 30% by weight of the product of at least one nonionic surfactant; and,

(d) optional minor substances selected. from the group consisting of metal ion sequestrants, solvents and perfumes.

Product form

The products of this invention are generally liquids and preferably aqueous. However, other product forms are also contemplated, including pastes and solids.

As can be appreciated, the form of the product is widely determined by end use and therefore liquids are generally suitable for use as hard surface cleaners, including cleaners for industrial, commercial and domestic cleaning and / or disinfection of hard surfaces, including metals, plastic materials or other polymers. , ceramics, and glass surfaces.

It is contemplated that the method of the invention may be applied to the cleaning of surfaces that are used to prepare food and beverages (for example, work surfaces, conveyor belts and tools) or other industrial, business and home surfaces such as sanitary, industrial, business and home fluid delivery applications, disinfection of medical, surgical or dental instruments, devices, aids or accessories, catheters, contact lenses, surgical clothing or surgical instruments, in horticultural applications such as sterilization of greenhouse surfaces, on soft surfaces, including fabrics (including clothing, towels and rags), and inanimate materials of biological origin (such as wood). The solid product forms are suitable for use as toilet and urinal blocks and for other uses where slow or delayed release of the components is required.

Examples of embodiments of the invention

In order that this invention may be further understood, it will be described hereinafter by way of illustration and non-limiting examples and comparisons.

The following examples were performed using a kitchen contamination model and a contamination process as described below. The soiling was chosen to use stubborn stains that would be difficult to bleach due to the hydrophobic or pyrolyzed nature of the stains.

Example 1

Curcumin / oil spots on umakarte

Pollution preparation

Flat tiles measuring 4 ”x 4” (10 x 10 cm) were cut from a white formica plate and their surfaces thoroughly cleaned using a commercially available “Jif” (TM) liquid abrasive cleaner. After rinsing with demineralized water, the tiles were allowed to dry at room temperature.

Curcumin / oil spots were prepared by mixing 19 g of vegetable oil and 180 g of ethanol and then adding 1 g of pure curcumin (pigment found in caricature). After thorough grinding, the resulting solution was sprayed onto the tiles using a propeller sprayer to provide uniform surface coverage. The tiles were allowed to dry for at least 10 minutes, during which time ethanol was evaporated leaving a sharp yellow, slightly sticky oil stain that could not be removed by wiping or rinsing with water. Curcumin is susceptible to photooxidation and soiled tiles should not be stored for more than 2 hours before use.

Preparation of bleach or surfactant solutions

The experiments were performed with hydrogen peroxide, PAP (peroxoadipoylphthalimide), peroxo-monosulfate and sodium hypochlorite (a well known inorganic bleaching agent).

Bleach solutions were prepared by dissolving the peroxide co-oxidizing agent in demineralized water and, if necessary, adding an oxygen transfer agent. Sodium hydroxide solution (5 mol dm ³ ) was added dropwise to adjust the pH to the desired value as determined using a pH meter. Additional demineralized water was added to the solution to reach the desired final volume.

In the examples described, the oxygen transfer agent was N-methyl-3,4-dihydroisoquinolinium p-toluenesulfonate. The preparation of this material is described in US 5360569 and US 5360568, which are incorporated herein by reference. The material is referred to below as quaternary imine salts.

The solutions of hydrogen peroxide were prepared to a final concentration of 3% (0.88 mol.dnr ³⁾ and used in conjunction with a 1% molar equivalent of the catalyst - the quaternary imine salts (0.0088 mol.dm ^'3, 0 , 30% by weight). In conjunction with the same quaternary imine salt level, potassium solutions of Caroate (TM: 6% by weight, equivalent to 3% by weight, 0.1 mol.dm ^{3 of} peroxomonosulphate) and PAP (6- [N-phthalimidoylperoxohexanoic acid: 2% by weight) were tested. , 0.012 moldm ³ ). The potassium peroxomonosulphate system was tested at pH 8.5 (but also higher pH values were used for hydrogen peroxide (which has higher pK _a ) and PAP (which is relatively insoluble at lower alkalinity). Addition of a wetting agent (1% by weight butyldigol mixture) (TM): diethylene glycol mono-n-butyl ether) further increases the solubility of PAP.

* (TM), diethylene glycol mono-n-butyl ether was added or used for comparison.

Pollution removal experiments

The examples were carried out at room temperature. A glass ring of 50 mm diameter and 15 mm height was placed above the center of the stained tile and 5 cm ³ of the aqueous bleach or surfactant solution was pipetted into the ring ring. The solution was left in contact with the stained tile surface for 30 seconds, after which the glass circle was removed and the solution was poured away. The tile was immediately rinsed with demineralized water for a further 30 seconds and then allowed to dry. Each solution was used to work two tiles.

The stain removal rate was assessed visually by a panel of at least 15 people using a standard scale. Tiles were graduated on an integer scale ranging from 0 to 5, where 0 indicates no visible removal of contamination and 5 corresponds to complete removal. A minimum of two stained tiles were treated with each bleach solution and for each system the mean score was calculated as the average score for both tiles.

The results are shown in Table 1 below. From the results presented in Table 1, it can be seen that a significant improvement in terms of hydrogen peroxide bleaching is obtained in the presence of a quaternary imine salt at both pH 10 and pH 10.5. A similar increase is not seen for either organic or inorganic peroxyacids.

Comparison of results with conventional cleaning / bleaching systems. It can be seen that the use of an oxygen transfer agent together with hydrogen peroxide provides results that are very favorably comparable to hypochlorite, and significantly better than for alkaline and surfactant based systems.

Table 1

System Without quaternary imine salt with 0.3% by weight of a quaternary imine salt 3% hydrogen peroxide at pH 10.0 0.1 1.3 3% hydrogen peroxide at pH 10.5 1.3 3.1 2% PAP / 1% Butyl Digol at pH 10.0 0.1 0.3 3% K-monoperoxosulfate at pH 8.5 0 0 1% NaOCl at pH 10 2.9 1% NaOCl at pH 10.5 3.8 Alkaline system at pH 10.0 0.2 Alkaline system at pH 10.5 1.6 stain color has intensified 0.1% Imbentin at pH 10.0 1.0 0.1% Imbentin at pH 10.5 1.5

-12Example 2

Baked fat / flour on enamel

Pollution preparation

Oleic acid (1 g), stearic acid (1 g) and Friol (TM) Italian oil (38

g) were mixed in a metal container and heated directly to 60 ° C using a cooker so that the mixture was liquefied. The demineralized water (100 g) is boiled and allowed to cool to 60 ° C before mixing with Italian flour (40 g), after which a thick paste has formed.

The organic acid-oil mixture and the flour paste were placed in a liquid can and demineralized water (280 g) was added. The fat blend was mixed for 5 seconds, allowed to stand for 10 seconds, and then stirred for a further 5 seconds. The contents of the liquefier were then transferred to a glass beaker and gently heated by direct heating on a hotplate. The mixture was allowed to boil for five minutes with constant stirring with a submersible stirrer. The mixture must not be allowed to adhere to the beaker or there must be no extensive cross-linking resulting in contamination that is too resistant to removal. The mixture was then transferred to a polyethylene beaker and allowed to cool before use.

Application of pollution

White enamel tiles (100 mm x 100 mm) were cleaned with a commercially available liquid abrasive cleaner ("Jif" [TM]), rinsed in demineralized water and allowed to dry. The tiles were then covered (about 0.5 mm) with a layer of fat / flour using a screen printing technique. A flexible rubber spatula is used to spread the mixture on the tile surface through a thin plastic screen, taking care to achieve a uniformly thin coating. The contaminated tiles were allowed to stand in the air overnight, obtaining an evenly matte surface. The tiles were baked on the middle oven shelf at 190 ° C for one hour, developing a light brown color, and allowed to cool for 2 hours before cleaning. Because it is expected to vary between

13 of these soiled and subsequently pyrolyzed tiles, it is important that comparisons are made with tiles taken from the same dose.

Preparation of bleach or surfactant solutions

Solutions were prepared as described for the curcumin-oil contamination removal experiments above with reference to TABLE 1 using the formulations listed in TABLE 2 below. Detergent effects were studied using the nonionic surfactant Neodol 91-5 (TM), a commercially available, slightly less pure, version of Imbentin 91-35 OFA (TM) used in the above curcumin-oil mixtures experiments. . Admox 10 (TM) is a C ₁₀ aminooxide surfactant.

Peracetic acid is used at a concentration equal to the concentration of HOO 'of the active oxidants present in the 3% hydrogen peroxide solution at the same pH (10.0).

Pollution removal experiments

Pollution removal was performed using a standard Wool Industries Research Association Abrasion Tester (WIRA: TM). Two contaminated tiles were cleaned simultaneously with the same solution to give duplicate results. The bleaching or surfactant solution (20 cm ³ ) was poured onto the tile surface and wiped off using a scrub head covered with two layers of pure "J" fabric (TM). Each tile was cleaned using 51 head moves. The tiles were then immediately removed from the apparatus, rinsed under running water and tapped dried using paper towels.

As mentioned above, although the color and ease of removal of contamination is the same for tiles covered with a specific fat-flour mixture, there is some variability between different doses of contamination. Therefore, the results shown in TABLE 2 below are grouped into kits (TABLES 2a, 2b and 2c), each performed using different dosages of a mixture of fat-flour contaminated tiles. Experiments using Jif (TM) liquid abrasive cleaner and Domestos MultiSurface Cleaner (TM), a commercial hypochlorite cleaning product for hard surfaces, are

-14 included in each series of experiments to provide comparative standards. The extent of stain removal was assessed visually by a panel of at least 5 people using a standard scale. The tiles were scaled on a scale ranging from 0 to 10, and panelists assigned an integer or half-number score to each tile. A score of 0 indicates no visible removal of contamination and 10 corresponds to complete removal. For each pollution control system, the mean score was calculated as the average score for both replicates.

By comparing the results with conventional cleaning / bleaching systems, it can be seen that the use of an oxygen transfer agent together with hydrogen peroxide provides results that are very favorably comparable to hypochlorite and hypochlorite-based commercial products and are significantly better than for alkaline systems and surfactants. substance based systems. From the second table it can be seen that while the quaternary imine salts show a reduced effect in the presence of a surfactant, the improvement over systems that do not contain quaternary imine salts is still measurable.

Table 2a

System Without quaternary imine salt with 0.3% by weight of a quaternary imine salt 3% hydrogen peroxide at pH 10.5 8.5 9.0 3% K-monoperoxosulfate at pH 8.5 5.6 5.6 Domestos Multi Surface Cleaner at pH 11.5 10 JIF at pH 11.0 5.8 - Alkaline system at pH 10.5 6.4 - 0.1% Neodol at pH 10.5 3.5

-15Table 2b

System Without quaternary imine salt with 0.3% by weight of a quaternary imine salt 3% hydrogen peroxide at pH 10.0 3.9 4.9 0,12% Peroxyacetic acid at pH 10,0 2.9 3.8 Domestos Multi Surging Cleaner at pH 11.5 9.1 PH 11.0 3.6 -

Table 2c

System Without quaternary imine salt with 0.3% by weight of a quaternary imine salt 3% hydrogen peroxide at pH 10.0 8.2 9.1 Domestos Multi Surging Cleaner at pH 11.5 10 3% NaOCl at pH 10.0 8.1

Table 2d

System Without quaternary imine salt with 0.3% by weight of a quaternary imine salt 3% hydrogen peroxide at pH 10.0 7.5 8.0 3% hydrogen peroxide and 0.1% Admox 10 at pH 10.0 7.3 7.9 Domestos Multi Surging Cleaner at pH 11.5 9.4 JIF at pH 11.0 4.3 -

piJ CW- 7 /

Claims (6)

An aqueous, volatile bleaching composition having a pH of 10 to 14, characterized in that it comprises hydrogen peroxide and a quaternary imine salt - an oxygen transfer agent, comprising ions of general structure: (P R ²⁾ C = N ^{+ (R3) (R4)} wherein: R ¹ and R ⁴ are in cis relationship and are substituted or unsubstituted radicals selected from the group consisting of hydrogen, phenyl, aryl, heterocyclic ring, alkyl and cycloalkyl radicals; R ² is a substituted or unsubstituted radical selected from the group consisting of hydrogen, phenyl, aryl, heterocyclic ring, alkyl, cycloalkyl, nitro, halo, cyano, alkoxy, keto, carboxylic acid and carboalkoxy groups; and R ³ is a substituted or unsubstituted radical selected from the group consisting of hydrogen, phenyl, aryl, heterocyclic ring, alkyl, cycloalkyl, nitro, halogen and cyano. Aqueous liquid bleaching composition according to claim 1, characterized in that hydrogen peroxide is present at a level of 0.5 to 10% by weight of the product. The aqueous liquid bleaching composition of claim 1, wherein the weight ratio of hydrogen peroxide to oxygen transfer agent is in the range of 5: 1 to 20: 1. Aqueous liquid bleaching composition according to claim 3, characterized in that the oxygen transfer agent is a substituted or unsubstituted isoquinolinium salt. An aqueous liquid bleaching composition according to claim 1 having a pH of 10 to 12 and comprising: (a) hydrogen peroxide at a level of 0,5 to 10% by weight of the product, (b) 0.001 to 10% by weight of the isoquinoline salt product; (c) 0.01 to 30% by weight of the product of at least one nonionic surfactant; and, (d) optional minor substances selected from the group consisting of metal ion sequestrants, solvents and perfumes. 6. A method of bleaching a soiled substrate comprising the step of treating said substrate with an aqueous liquid bleaching composition as claimed in claims 1 to 5.