MXPA06011447A - Liquid bleaching compositions - Google Patents

Abstract

The present invention relates to liquid bleach additive compositions comprising an immido-type peroxy acid and a source of protons.

Description

LIQUID BLEACHING COMPOSITIONS TECHNICAL FIELD The present invention relates to a liquid bleach additive composition, which can be used to whiten fabrics together with a conventional particulate detergent or liquid for laundry washing.

BACKGROUND OF THE INVENTION The liquid bleaching compositions most frequently found suitable for bleaching stains on fabrics, are based on halogen bleaches, in particular hypochlorite bleaches or oxygen peroxide bleaches, such as hydrogen peroxide. Halogen bleaches are extremely effective bleaching agents; however, they also have many disadvantages which may in turn dissuade the consumer from choosing the halogen-containing product. For example, halogen bleaches, in particular chlorine bleaches, emit a pungent odor during and after use (e.g., on the consumer's hands and / or the surfaces treated with them) which some consumers find unpleasant. Furthermore, it is known in the industry that compositions containing halogen bleach (usually hypochlorite) are relatively aggressive to fabrics and can cause damage when used in relatively high concentrations and / or repeatedly. In particular, the consumer may perceive damage to the fabric itself (e.g., loss of tensile strength) or damage to the intensity of the color of the fabric. Although damage to color and fabric can be minimized by the use of peroxide bleaches such as hydrogen peroxide, the bleaching performance characteristics of these peroxide bleaches are much less desirable than those of halogen bleaching agents. Therefore, liquid bleaching compositions comprising preformed peroxycarboxylic acid have been developed. It has been found that these bleaching compositions comprising preformed peroxycarboxylic acid show a good bleaching performance when used in laundry applications, especially so-called bleaching additives, and are also safe for fabrics and / or colors. Indeed, peroxycarboxylic acids are known in the industry, for example from European Patent Application EP-A-0 435 379. Furthermore, the use of this peroxycarboxylic acid to treat the fabrics has been described in the industry, e.g. eg, in WO 00/27963, WO 00/27964, WO 00/27965, WO 00/27966, WO 00/27967, WO 00/27977 and WO 2002/12431. It has been found that the chemical stability of the currently known bleaching additives based on peroxycarboxylic acid is below expectations. In addition, the preformed peroxycarboxylic acids represent a challenge to be handled in bleach additive manufacturing plants. These difficulties have recently been overcome with the use of imido type peroxyacids, which being solid are safe to be handled in the manufacturing plants, and can also be stabilized within liquid bleach additive formulations by suspending them as solid particles. A specific class of imido-type peroxyacids, especially the imido-type peroxyalkane acids, in particular the phthalimido-peroxyalkane acids, and in particular the e-phthalimido-peroxyhexanoic acid (PAP). However, given their chemical structure, the peroxyacid type, when present in the bleaching additives, are not stable when used in the pH of the washing solution formed by the conventional particulate detergents for washing clothes. By "bleaching additives" refers herein, to a composition that is used in conjunction with, this means that a conventional laundry detergent, in particular a particulate laundry detergent, is added to the washing machine together with a laundry detergent. , in a laundry washing operation. Usually, conventional particulate laundry detergents (such as ARIEL powder detergent) provide a pH in the wash greater than 9.5. The imide portion of the peracid is hydrolyzed quantitatively and irreversibly at this pH (as described in REINHARDT, G. 1994b: Imldoperoxicarbonsáuren ais potentielle Bleichmittel für Waschmittelindustrie.

SOFW-Joumal 120: 411-416). This leads to a hydrophilic molecule, which has been observed to provide a bleaching performance of the washing solution per se in the washing machine (formed by laundry detergent, bleaching additive and water) instead of stains on the fabrics that are washed in the washing machine. Indeed, currently known imido type peroxy acid bleach additives failed to provide a suitable bleaching performance in spots when used in combination with particulate detergents. This effect is not observed or at least to an insignificant extent in the so-called pretreatment whitening compositions comprising imido-type peroxyacids, in which the pretreatment is applied to the cloth before washing or rinsing and allowed to act thereon for a certain amount. effective time. Therefore, it is an object of the present invention to provide a liquid bleaching additive comprising imido-type peroxyacids, which provides an effective bleaching performance on soiled fabrics, when used in conjunction with a conventional particulate laundry detergent. It has now been discovered that liquid bleach additives containing a solid peroxyacid and a source of protons according to the present invention satisfy the aforementioned objective. An advantage of the compositions of the present invention is that the liquid bleaching additives herein are suitable for bleaching different types of fabrics including natural fabrics, (eg, fabrics made of cotton, and linen), synthetic fabrics such as those made of polymeric fibers of synthetic origin (eg, polyamide-elastane) as well as fabrics that are made of both natural and synthetic fibers. For example, the liquid bleach additives of the present invention can be used in synthetic fabrics despite the persistent bias against the use of bleaching agents in synthetic fabrics, as evidenced by the warnings on commercially available clothing labels and bleaching compositions, as the compositions containing hypochlorite. Another advantage of the liquid bleach additives according to the present invention is that they can be used in a variety of conditions, that is, in hard and soft water. Yet another advantage of the compositions of the present invention is that they also exhibit an effective stain removal performance in various spots including enzymatic stains and / or greasy stains.

BRIEF DESCRIPTION OF THE INVENTION The present invention includes a liquid bleach additive composition having a viscosity of up to 5 Pa.s (5000 cP) and / or comprising at least 50% by weight of the total water composition, and further comprising a peroxyacid type Mido and a proton source having at least one acid donor portion of protons in water at a pH of less than 7.5, wherein said composition comprises at least 0.80 mmoles of available protons at a pH of less than 7.5 per gram of the composition. The present invention further includes a kit comprising at least two compositions, wherein a first composition comprises an imido-type peroxyacid and optionally a proton source having at least one proton donor acid portion in water at a pH lower than 7.5, and wherein a second composition comprises a source of protons having at least one acid donor portion of protons in water at a pH of less than 7.5, wherein said compositions when combined comprise at least 0.80 mmoles of available protons at a pH of less than 7.5 per gram of the mixed compositions. The present invention also includes a process for treating fabrics, which comprises the steps of forming an aqueous bath comprising water, a conventional detergent for washing clothes, preferably a particulate detergent for washing clothes, and a liquid bleach additive composition in accordance with the present invention, and subsequently contacting said fabrics with said aqueous bath. In addition, the present invention includes a process for treating fabrics, which comprises the steps of forming an aqueous bath containing water, a conventional laundry detergent, preferably a particulate detergent for washing clothes, and a liquid composition of bleach additive formed by at least two compositions of the kit according to the present invention, and subsequently contacting said fabrics with said aqueous bath. In addition, the present invention includes the use of a proton source having at least one donor acid portion of protons in water at a pH of less than 7.5 in a liquid bleach additive composition comprising a imido-type peroxyacid, wherein said composition it comprises at least 0.80 mmoles of available protons at a pH of less than 7.5 per gram of the composition, to provide an effective bleaching performance on soiled fabrics, when used in conjunction with a conventional particulate laundry detergent.

BRIEF DESCRIPTION OF THE FIGURES Figure 1 is a graph showing a titration curve of an average solution for washing formed by a conventional particulate detergent for washing clothes. Indeed, 110 grams of ARIEL® granular detergent were dissolved in 12 liters of water, which represents the recommended dosage of a granulated detergent in a washing machine (under European washing conditions), and titrated with a composition comprising 10% citric acid and 90% water. The graph shows the pH of the wash solution against the concentration of protons that are obtained from the citric acid-containing composition.

DETAILED DESCRIPTION OF THE INVENTION The liquid bleach additive composition The liquid bleach compositions in the present invention are so-called liquid bleach additive compositions, which are suitable for use in conjunction with a conventional laundry detergent and in particular, with particulate detergents for the washing of laundry detergents. clothes, to treat fabrics (stained). The terms "additive" or "composition (bleach) to be used during washing" refer to the compositions that are preferably employed in the specific process of treating, preferably bleaching, the fabrics as included by the present invention. Indeed, the additive compositions are added together with a conventional laundry detergent (preferably a particulate detergent for laundry) inside a washing machine and are active in the same wash cycle. In contrast, so-called 'pre-stain' or 'prewash treatment' compositions are applied, mainly undiluted, on the fabrics prior to washing or rinsing the fabrics and left on to act on them for an effective period of time . In addition, the so-called 'soaking' or 'added during rinsing' compositions are contacted, mainly in diluted form, with the fabrics before or during the rinsing of the fabrics with water.

The compositions according to the present invention are liquid compositions as opposed to a solid or a gas. The liquid bleach additive compositions have a viscosity of up to Pa.s (5000 cps) at 20 s "1 and / or contain at least 50% by weight of the total water composition.The liquid bleach additive compositions preferably have a viscosity of up to 5000 cps at 20 s. "1, more preferably from 5 Pa.s (5000 cps) to 0.05 Pa.s (50 cps), more preferably from 2 Pa.s (2000 cps) to 0.05 Pa.s (50 cps) and with the highest preference from 1.2 Pa.s (1200 cps) to 0.05 Pa.s (50 cps) at 20 s "1 and 20 ° C when measured with a Carri-Med rheometer model CSL2 100® (supplied by TA Instruments) with an axis 4 cm conical in stainless steel (linear increments of 0.1 to 100 sec 1 in maximum of 8 minutes) The liquid bleach additive compositions are preferably not paste or paste-like compositions, in addition or alternatively, (preferably in addition) the compositions liquid bleach additives comprise at least 50%, preferably 50% to 95%, more preferably 70% to 95%, even more preferably 75% to 95% by weight or of the total composition of water. Preferably, the pH of the compositions according to the present invention is from 0.1 to 6.5, more preferably from 0.5 to 5, even more preferably from 1 to 4. The formulation of the compositions according to the present invention in the range pH acid contributes to the chemical stability of the additive compositions according to the present invention. The pH of the composition is preferably below the pKa of the acid corresponding to the imido-type peroxyacid used. It is believed that the acid pH controls / limits the formation of highly reactive species which are unstable in the acid medium in storage, and thereby contribute to the stability of the compositions during prolonged periods of storage. The pH of the compositions is determined by the concentration and type of the proton source as discussed below. The bleaching performance of liquid bleach additive compositions can be evaluated by means of the following test methods in various types of bleach stains: A suitable test method for evaluating bleaching performance on a soiled fabric under additive conditions (also referred to herein) as conditions "during the wash cycle") is as follows: A liquid bleach additive composition is used in the wash cycle of a conventional washing machine. The liquid bleach additive composition is added together with a conventional particulate laundry detergent (such as DASH® powder), TIDE®, ARIEL® tablets, ARIEL® powder). The liquid composition of bleaching additive is dosed at 50 to 100 mL per load of laundry and the conventional detergent for washing clothes is dosed at 110 grams per load of clothes for granules and 2 tablets per load of laundry for tablets (recommended dosages) . Dirty fabrics are washed in the washing machine according to the standard procedure of the washing machine at a temperature of 30 ° to 70 ° C for 10 to 100 minutes and then rinsed. The reference composition (s) in the comparative test undergo the same treatment. Fabrics / samples soiled with for example tea, coffee and the like may be commercially available from E.M.C. Co. Inc. A visual classification can be used to assign differences in panel sorting units (PSU) on a scale of 0 to 4, where 0 means there is no discernible difference in bleaching performance between a liquid bleach additive composition according to the present invention and a reference composition and 4 means a perceptible difference in the bleaching performance between a liquid bleach additive composition according to the present invention and a reference composition.

Imido-type peroxyacids The bleaching composition of the present invention comprises a imido-type peroxyacid. Said preferred imide type peroxyacid is a solid, substantially water-insoluble, preformed imido peroxyacid. In a preferred embodiment of the present invention, the imido-type peroxyacid has the general formula: X-R-C (0) OOH wherein R is a linear or branched, substituted or unsubstituted hydrocarbon chain having at least 1 carbon atom and X is a substituted imide, preferably a substituted imide wherein the imide nitrogen forms a bond with R. For a " "Substituted measure" is meant here an imide having a substitution in nitrogen. Preferably, the imido-type peroxyacid is in accordance with the general formula: R1-CO-N-CO-R2 R - C (O) OOH wherein R1 and R2 are, independently, linear or branched, substituted or unsubstituted hydrocarbon chains having at least 1 carbon atom, preferably aliphatic or aromatic hydrocarbon chains and can form a ring. More particularly, the R group preferably comprises from 2 to 24 carbon atoms. Alternatively, the R group can be a branched alkyl chain comprising one or more side chains which comprise substituent groups selected from the group consisting of aryl, halogen, ester, ether, amine, amide, substituted-italic, imide, hydroxide, sulfide , sulfate, sulfonate, carboxylic, heterocyclic, nitrate, aldehyde, ketone or mixtures thereof.

In a preferred peracid, the group X, according to the general formula mentioned above, is a phthalimido group. Thus, the particularly preferred imido-type peroxyacids herein are those having the general formula: wherein R is a C1-C20 alkyl group and wherein A, B, C and D are, independently, hydrogen or substituent groups individually selected from the group comprising alkyl, hydroxyl, nitro, halogen, amino, ammonium, cyanide, carboxylic, sulfate , sulfonate, aldehydes or mixtures thereof. In a preferred aspect of the present invention R is an alkyl group having from 3 to 12 carbon atoms, more preferably from 5 to 9 carbon atoms. Preferred substituent groups A, B, C and D are linear or branched alkyl groups having from 1 to 5 carbon atoms, but more preferably hydrogen. In a preferred embodiment herein, the imido-type peroxyacid is an imido-type alkanoic peroxyacid, preferably an alkanoic acid-phthalimido peroxyacid, more preferably the imido-type peroxyacid is selected from the group comprising e-phthalimido peroxyhexanoic acid (also known as phthalimido acid) peroxicaproid (PAP), phthalimido peroxyheptanoic acid, phthalimido peroxioctanoic acid, phthalimido peroxinonanoico acid, phthalimido peroxydecanoic acid, and mixtures thereof, and more preferably e-phthalimido peroxyhexanoico acid (PAP) The peroxyalcanico phthalimido acid suitable has the general formula: or wherein R is selected from C 1-4 alkyl and n is an integer from 1 to 5. The PAP (e-phthalimido peroxyhexanoic acid) as mentioned above is according to the aforementioned formula wherein R is CH 2 and n is 5. The PAP of Preference is used as a solid or wet tablet substantially insoluble in water and is available from Ausimont under the trademark Eureco®. Said peroxy acid type can be present in the composition at a level of 0.1% to 10%, more preferably from 0.1% to 5%, and most preferably from 1% to 5% by weight of the total composition. Alternatively, the imido-type peroxyacid may be present at a much higher level, for example, from 10% to 40%, more preferably from 15% to 30%, most preferably from 20% to 25% by weight of the total composition.

Proton source The compositions herein comprise a proton source having at least one proton donor acid moiety in water at a pH below 7.5, wherein said composition comprises at least 0.80 mmoles of available protons at a pH less than 7.5 per gram of the composition. The compositions herein may comprise a mixture of suitable sources of protons. By "source of protons" is meant at present a species with Lewis / Bronsted acid behavior, that is, a species that, in water solution, is capable of donating a proton or accepting an electron of another species. By "mmoles of available protons at a pH lower than 7.5 per gram of the composition" refers to the available proton concentration (in mmoles per gram of the composition), this means that the free protons or the protons that can be dissociated , at a pH lower than 7.5, which are capable of being supplied to species (alkaline / basic) present in the washing solution and thereby reduce the pH in the washing solution formed by a conventional washing detergent , preferably a conventional particulate detergent for washing clothes.

The concentration (in mmoles per gram of the composition) of available protons in a given composition is equivalent to the amount in mmoles of a solution of 1 M sodium hydroxide (1 mole of NaOH in 1 liter of demineralized water) that is needed to bring the pH of 100 grams of the composition determined to a value of 7.5 and divided by 100. For example, for 100 grams of a composition consisting of 5 grams of citric acid and 95 grams of water (citric acid has a weight molar of 192.2 and three acid protons donated at a pH lower than 7.5), 79 mmoles of a solution of 1 M sodium hydroxide are required to bring the pH up to a value of 7.5. This means that said composition comprises a proton-donor proton source in water at a pH below 7.5 and wherein said proton source is present at a concentration of 0.79 mmoles of available protons at a pH of less than 7.5 per gram of the composition. . Alternatively, for 100 grams of a composition consisting of 5 grams of succinic acid and 95 grams of sodium sulfate (the succinic acid has a molar weight of 118.09 and two acid protons donated at a pH lower than 7.5), 85 mmoles a solution of 1 M sodium hydroxide is required to bring the pH to a value of 7.5. This means that said composition comprises a proton donor proton source in water at a pH lower than 7.5 and wherein said proton source is present at a concentration of 0.85 mmoles of available protons at a pH lower than 7.5 per gram of the composition .

In addition, for 100 grams of a composition consisting of 4 grams of succinic acid, 4 grams of citric acid and 92 grams of water, 130 mmol of a 1M solution of sodium hydroxide are required to bring the pH up to a value of 7.5. This means that said composition comprises a proton donor proton source in water at a pH lower than 7.5 and wherein said proton source is present at a concentration of 1.30 mmoles of available protons at a pH lower than 7.5 per gram of the composition . The proton source herein may preferably be present in a concentration of at least 0.80, preferably at least 0.90, more preferably 1.0, more preferably 1.1, even more preferably 1.8, even more preferably 2.0 and most preferably 2.0 mmoles of available protons at a pH lower than 7.5 per gram of the composition. In a preferred embodiment herein, the proton source herein may be present in a concentration of up to 5, preferably up to 4.5, more preferably 4, even more preferably 3.5, even more preferably 3.0, even with more preferably 2.7 mmoles of available protons at a pH lower than 7.5 per gram of the composition. Suitable sources of protons of the present invention may be organic or inorganic. The organic sources of suitable protons of the present are selected from the group consisting of: succinic acid, malonic acid, citric acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, italic acid, isophthalic acid, terephthalic acid, acid hemimellitic, trimellitic acid, trimesic acid, melophanoic acid, prenitic acid, pyrolelitic acid, benzene pentacarboxylic acid, and melific acid and mixtures thereof. Suitable inorganic sources of protons herein are selected from the group comprising: hydrogen sulphide, and phosphorus dihydride, and mixtures thereof. Preferably said source of protons of the present is selected from the group comprising citric acid, succinic acid, malonic acid, glutaric acid, and adipic acid and mixtures thereof. More preferably said proton source included herein is selected from the group comprising citric acid, succinic acid and malonic acid, and mixtures thereof. Most preferably, said source of protons in the present is citric acid. They are not suitable as proton sources in the present, for example, sodium hydrogen carbonate, ammonium sulfate, monoethanol-ammonium sulfate, percarboxylic acids (such as imido-type peroxyacids, such as PAP), peracetic acid, and diperpimelic acid. Indeed, without theoretical limitations of any kind, the aforementioned list of inadequate sources of protons fail to donate (or at least donate sufficiently) protons at a pH below 7.5. In a highly preferred embodiment herein, said proton source does not include the imido-type peroxyacid present in the compositions in accordance with the present invention. In a preferred embodiment herein, the composition herein comprises citric acid in a concentration of at least 0.051 grams per gram of the composition (resulting in a concentration of at least 0.80 mmoles of available protons at a pH below 7.5. per gram of the composition), preferably at least 0.083 grams per gram of the composition (resulting in a concentration of at least 1.3 mmoles of available protons at a pH of less than 7.5 per gram of the composition), and with the highest preferably at least 0.138 grams per gram of the composition (resulting in a concentration of at least 2.2 mmoles of protons available at a pH of less than 7.5 per gram of the composition). In another preferred embodiment herein, the composition herein comprises succinic acid in a concentration of at least 0.047 grams per gram of the composition (resulting in a concentration of at least 0.80 mmoles of available protons at a pH below 7.5. per gram of the composition), preferably at least 0.076 grams per gram of the composition (resulting in a concentration of at least 1.3 mmoles of available protons at a pH of less than 7.5 per gram of the composition), and with the highest preference at least 0.127 grams per gram of the composition (resulting in a concentration of at least 2.2 mmoles of protons available at a pH of less than 7.5 per gram of the composition). In another preferred embodiment herein, the composition herein comprises malonic acid at a concentration of at least 0.0416 grams per gram of the composition (resulting in a concentration of at least 0.80 mmoles of available protons at a pH below 7.5. per gram of the composition), preferably at least 0.0675 grams per gram of the composition (resulting in a concentration of at least 1.3 mmoles of available protons at a pH lower than 7.5 per gram of the composition), and with the highest preferably at least 0.112 grams per gram of the composition (resulting in a concentration of at least 2.2 mmoles of protons available at a pH lower than 7.5 per gram of the composition). In another preferred embodiment herein, the composition herein comprises glutaric acid in a concentration of at least 0.0528 grams per gram of the composition (resulting in a concentration of at least 0.80 mmoles of available protons at a pH below 7.5. per gram of the composition), preferably at least 0.0859 grams per gram of the composition (resulting in a concentration of at least 1.3 mmoles of available protons at a pH of less than 7.5 per gram of the composition), and with the highest preferably at least 0.143 grams per gram of the composition (resulting in a concentration of at least 2.2 mmoles of protons available at a pH of less than 7.5 per gram of the composition). In another preferred embodiment herein, the composition herein comprises adipic acid in a concentration of at least 0.0585 grams per gram of the composition (resulting in a concentration of at least 0.80 mmoles of available protons at a pH below 7.5. per gram of the composition), preferably at least 0.0950 grams per gram of the composition (resulting in a concentration of at least 1.3 mmoles of available protons at a pH of less than 7.5 per gram of the composition), and more preferably at least 0.158 grams per gram of the composition (resulting in a concentration of at least 2.2 mmoles of protons available at a pH of less than 7.5 per gram of the composition). In view of the foregoing, the present invention also includes a liquid bleach additive composition having a viscosity of up to 5 Pa.s (5000 cps) and / or comprising at least 50% by weight of the total water composition, a peroxyacid type imido and a source of protons, wherein said source of protons is chosen from the group consisting of: citric acid which is present at a level of at least 5.1%; succinic acid that is present at a level of at least 4.7%; malonic acid that is present at a level of at least 4.2%; glutaric acid that is present at a level of at least 5.3%; and adipic acid which is present at a level of at least 5.9%; and mixtures of these. The foregoing is also applicable to the case in accordance with the present invention as described herein. The Applicant has discovered that by reducing the pH in the wash solution formed by a conventional laundry detergent, preferably a conventional particulate laundry detergent (including powders, granules, pellets and tablets) and a bleach based additive. in imido type peroxide, preferably based on PAP, the whitening performance through washing, of the bleaching additive can be significantly improved. Indeed, it has surprisingly been discovered that at a pH higher than 9, the liquid peroxyacid molecule, preferably the PAP molecule, is irreversibly hydrolyzed to a hydrophilic molecule, which fails to be able to penetrate the hydrophobic fibers of the fibers. fabrics and therefore fails to be able to penetrate the bleachable stains present on it. This leads to a limited whitening performance in stained fabrics, while maintaining a good whitening performance of the washing solution, which is an aqueous solution and thus hydrophilic. Indeed, the bleaching activity of imido-type peroxyacids is more optimal in the pH range of 9.0 to 8.0. For example, the bleaching activity of PAP is more optimal at a pH of 8.4. However, conventional laundry detergents and in particular conventional granulated laundry detergent are highly dampened compositions that provide a wash solution having a pH in the range of 9.8-10. Indeed, as shown in Figure 1 herein, significant damping can be observed for conventional granular laundry washing compositions. As shown in Figure 1, to reduce the pH of the wash solution formed by the conventional particulate laundry detergent to less than 9, preferably less than 8.8, high amounts of protons are needed. Indeed, at least 80 mmoles of protons are needed to bring the pH of the wash solution to a pH below 9.5 and 130 mmoles of protons are needed to bring the pH of the wash solution to a pH below 8.8. . The protons have to be added together with the particulate bleach additive for washing clothes containing imido-type peroxyacid, as described herein. Indeed, the bleach additive herein needs to contain high amounts of free acid (ie, available protons) also referred to as reserve acidity. This reserve acidity is supplied by the proton sources herein. For example, at a dosage of 162 grams of the particulate composition of bleach additive according to the present invention by loading clothes 130 mmoles of protons available at a pH lower than 7.5 (162 grams per 0.80 mmoles of available protons at a lower pH at 7.5 per gram of the composition) are available to displace the damping of the wash solution provided by the particulate detergent for laundry. It has been found that by adding a sufficient amount of reserve acidity within an imido-type peroxy acid bleach-based additive of the present invention, the bleaching performance of the additive in one operation during the wash cycle is significantly improved compared to the bleaching additives that do not contain or contain low reserve acidity used in a similar operation.

Optional Ingredients The compositions herein may further comprise a variety of other optional ingredients, such as surfactants, fillers, chelating agents, radical scavengers, antioxidants, stabilizers, enhancing additives, polymeric for suspending the soil, inhibitors of dye transfer, solvents, foam controlling agents, foam enhancers, brighteners, perfumes, pigments, dyes and the like.

POLYMERIC SYSTEM The composition of the present invention may comprise a gum-like polymer, which is preferably selected from the group consisting of polysaccharide hydrocolloids, xanthan gum, guar gum, succinoglycan gum, cellulose, derivatives of any of the foregoing and mixtures thereof. In a preferred aspect of the present invention, the gum-type polymer is a succinoglycan gum or a derivative thereof. The rubber-like polymer is preferably present at a level from 0.01% to 10%, more preferably from 0.05% to 3%, even more preferably from 0.1% to 1.0%.

Surfactants The compositions of the present invention may comprise a surfactant or a mixture thereof including nonionic surfactants, anionic surfactants, cationic surfactants, zwitterionic surfactants and / or amphoteric surfactants. Typically, the compositions according to the present invention may comprise up to 10% by weight of the total composition of a surfactant or a mixture thereof, preferably up to 5% and more preferably up to 2%.

Hydrotropes The compositions of the present invention may comprise a hydrotrope or a mixture thereof. Hydrotropes are a special class of compounds that are efficient solubilizers, because they can self-associate in an aqueous medium influencing the formation of micelles and microemulsions. Hydrotropes suitable for use herein may include the alkylbenzene sulfonates based on toluene, xylene and eumen, polyhydroxybenzene, the sodium salts of lower alkanols and the aromatic acid derivatives are generally considered to be effective hydrotropes. Typically, the compositions according to the present invention can comprise up to 5% by weight of the total composition of a hydrotrope or a mixture thereof, preferably up to 1% and more preferably up to 1%.

Chelating Agents The compositions of the present invention may comprise a chelating agent as an optional Ingredient. Suitable chelating agents can be any of those known to those skilled in the art, such as those selected from the group comprising phosphonate chelating agents, amino carboxylate chelating agents, other carboxylate chelating agents, aromatic chelating agents with polyfunctional substitutions, ethylene diamine N, N'-disuccinic, or mixtures thereof. The presence of chelating agents contribute to further improve the chemical stability of the compositions. A chelating agent may also be desired in the compositions of the present invention since it allows to increase the ionic strength of the compositions herein and thereby their removal performance and bleaching of spots on various surfaces. Phosphonate chelating agents suitable for use herein may include ethan-1-hydroxy bisphosphonates (HEDP), alkylene poly (alkylene phosphonate), as well as amino phosphonate compounds, including amino aminotri (methylene phosphonic acid) (ATMP), nitrilotris (methylene phosphonic acid) (NTP), ethylenediamine tetra (methylene phosphonic acid), and diethylene triamine penta (methylene phosphonic acid) (DTPMP) of alkali metals. The phosphonate compounds may be present either in their acid form or as salts of different cations in some or all of their acid functional groups. The phosphonate chelating agents that are preferred to be used herein are diethylene triamine pentamethylene phosphonate (DTPMP) and ethane 1-hydroxydiphosphonate (HEDP). These phosphonate chelating agents are commercially available from Monsanto under the trade designation DEQUEST®. In the compositions herein also aromatic chelating agents with polyfunctional substitutions may be useful. See US Pat. no. 3, 812,044 granted to Connor and coi. on May 21, 1974. Preferred compounds of this type in acid form are dihydroxydisulfobenzenes such as 1,2-dihydroxy-3,5-disulfobenzene. A preferred biodegradable chelating agent to be used herein is ethylene diamine N, N'-disuccinic acid or the alkali metal, alkaline earth, ammonium salts or salts of ammonium substitutes thereof or mixtures thereof. Ethylene diamine N, N'-disuccinic acids, especially the (S, S) isomer, have been extensively described in U.S. Pat. no. 4,704,233 by Hartman and Perkins of November 3, 1987. Ethylenediamine-N, N'-disuccinic acids, for example, are commercially available under the trade name ssEDDS® from Palmer Research Laboratories. Suitable aminocarboxylates for use herein include ethylenediamine tetraacetates, diethylenetriamine pentaacetates, diethylenetriamine pentaacetate (DTPA), N-hydroxyethylethylenediamine triacetates, nitrilotriacetates, ethylenediamine tetrapropionates, triethylenetetraaminehexaacetates, ethanoldiglicines, propylenediaminetetraacetic acid (PDTA), and methylglycine acid. diacetic (MGDA), both in their acid form or in the form of alkali metal, ammonium and substituted ammonium salts. Particularly suitable aminocarboxylates for use herein are diethylenetriaminepentaacetic acid, propylenediaminetetraacetic acid (PDTA) which, for example, is commercially available from BASF under the trade name Trilon FS® and methylyglycinateacetic acid (MGDA).

Some additional carboxylate chelating agents to be used herein include salicylic acid, aspartic acid, glutamic acid, glycine, malonic acid or mixtures thereof. Another chelating agent to be used in the present has the following formula: wherein Ri, R2, R3, and R4 are independently selected from the group comprising -H, alkyl, alkoxy, aryl, aryloxy, -Cl, -Br, -NO2, -C (O) R ', and -S02R "; wherein R 'is selected from the group comprising -H, -OH, alkyl, alkoxy, aryl, and aryloxy; R "is selected from the group comprising alkyl, alkoxy, aryl, and aryloxy; and R5, R6, R7, and Rs are independently selected from the group comprising -H and alkyl. Particularly preferred chelating agents to be used herein are amino aminotri (methylene phosphonic acid), diethylenetriamine pentaacetic acid, diethylene triamine pentamethylene phosphonate, 1-hydroxyethane diphosphonate, ethylene diamine N, N'-disuccinic acid and mixtures thereof. Typically, the compositions according to the present invention comprise up to 5% by weight of the total composition of a chelating agent or mixtures thereof, preferably from 0.01% to 1.5% by weight and, more preferably from 0.01% to 0.5%. %. Radical scavengers The compositions of the present invention may comprise a radical scavenger or a mixture thereof. Radical scavengers suitable for use herein include the well known mono-substituted dihydroxybenzenes and their analogs, the alkyl and aryl carboxylates, and mixtures thereof. Preferred radical scavengers for use herein include di-tert-butyl hydroxytoluene (BHT), hydroquinone, di-tert-butyl hydroquinone, mono-tert-butyl hydroquinone, tert-butyl-hydroxyanisole, benzoic acid, toluic acid, catechol, t-butyl catechol, benzylamine, 1, 1, 3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane, n-propyl gallate or mixtures thereof and highly preferred is di-tert-butyl hydroxytoluene. These radical scavengers such as N-propyl gallate can be commercially available from Ñipa Laboratories under the trade name Nipanox S1®. Free radicals, when used, are typically present herein in amounts up to 10% by weight of the total composition, preferably up to 0.5% by weight. The presence of free radicals can contribute to the chemical stability of the bleaching compositions of the present invention as well as the safety profile of the compositions of the present invention.

Stabilizers The compositions of the present invention may further comprise a stabilizer. Examples of inorganic stabilizers include sodium stannate and various alkali metal phosphates such as the well known sodium tripolyphosphates, sodium pyrophosphate and sodium orthophosphate.

Polymer for suspending dirt The compositions according to the present invention may further comprise a polyamine polymer for suspending dirt or mixtures thereof, as an optional ingredient. Any polyamine polymer can be used for the suspension known to those experienced in the industry. Polyamine polymers particularly suitable for use herein are polyalkoxylated polyamines. Typically, the compositions include up to 10% by weight of the total composition of this polyamine polymer for the suspension or mixtures thereof, preferably from 0.1% to 5% and more preferably from 0.3% to 2%. The compositions herein may also include other polymeric release agents known to those experienced in the industry. These polymeric release agents are characterized by having both hydrophilic segments, to hydrophilize the surface of the hydrophobic fibers, such as polyester and nylon, and hydrophobic segments, to deposit on the hydrophobic fibers and remain adhered to them until the end of the cycles of washing and rinsing and, in that way, serve as an anchor for the hydrophilic segments. This allows stains that occur after treatment with the release agent to be more easily cleaned in subsequent washing procedures. If used, the release agents will generally comprise from 0.01% to 10.0%, by weight, of the detergent composition herein, usually from 0.1% to 5%, preferably from 0.2% to 3.0%.

Brightener Any optical brighteners, fluorescent whitening agents or other whitening or whitening agents known in the industry can be incorporated into the present compositions when they are designed for the treatment or washing of fabrics, at levels usually from about 0.05% to about 1.2%, by weight, of the detergent composition herein.

Minor ingredients The composition described herein may also comprise minor ingredients such as pigments or dyes, foam control agents, dye transfer inhibitors, foam enhancers and perfumes.

Processes for treating fabrics The present invention includes a process for treating fabrics, which comprises the steps of forming an aqueous bath comprising water, a conventional laundry detergent, preferably a granular detergent for washing clothes, and a liquid bleach additive composition in accordance with the present invention, and subsequently contacting said fabrics with said aqueous bath. In a highly preferred embodiment herein, the liquid bleach additive compositions according to the present invention are dosed here to provide at least 80 mmol, preferably 100 mmol, more preferably 130 mmol, even more preferably 180 mmol, most preferably 210 mmoles of available protons at a pH lower than 7.5 per load of laundry. Indeed, a sufficient amount of the liquid bleach additive composition is added to provide the above-mentioned amounts of available protons at a pH below 7.5. Typically, the liquid bleach additive compositions according to the present invention are dosed at a minimum of 50 grams per laundry load, preferably from 55 grams to 170 grams, more preferably 60 grams to 110 grams. The dosage of the liquid bleach additive composition herein depends on the level of available protons at a pH less than 7.5 per gram of the composition. Indeed, compositions having proton levels available at a pH of less than 7.5 per gram of the composition at the minimum level required herein (0.8 mmol per gram of the composition) require a higher dosage (162.0 grams, for example. , donate 130 mmoles of available protons at a pH lower than 7.5 per load of clothes). Compositions having proton levels available at a pH of less than 7.5 per gram of the composition above the minimum level required herein (eg, 1.3 mmol per gram of the composition) require a lower dosage (100 grams for, eg, donate 130 mmoles of available protons at a pH below 7.5 per load of clothing). In addition, the present invention includes a process for treating fabrics, which comprises the steps of forming an aqueous bath comprising water, a conventional laundry detergent, preferably a granular laundry detergent, and a liquid composition. of bleach additive formed by at least two compositions of the kit according to the present invention, and subsequently contacting said fabrics with said aqueous bath. In a specific embodiment herein, wherein the liquid bleach additive composition is formed by at least two compositions of the kit according to the present invention, mixing of the at least two compositions of said kit can occur prior to forming said bath aqueous (that is, before adding it to the washing machine) and / or at the same time as the formation of said aqueous bath (ie, in the washing machine). In a highly preferred composition herein, the combination of the compositions in the kit according to the present invention are dosed herein to provide at least 80 mmoles, preferably 100 mmoles, more preferably 130 mmoles, still more preferably 180 mmole, most preferably 210 mmole of protons available at a pH below 7.5 per load of laundry. Typically, the combination of the compositions in the kit according to the present invention is dosed at a minimum of 50 grams per laundry load, preferably from 55 grams to 170 grams, more preferably from 60 grams to 110 grams. As outlined herein, the dosage of the liquid bleach additive composition herein depends on the level of available protons at a pH less than 7.5 per gram of the composition. The treatment processes, preferably the bleaching of fabrics according to the present invention, provide an effective bleaching performance as well as an effective performance of stain removal. The process of treating the fabrics herein comprises the steps of forming an aqueous bath comprising water, a conventional laundry detergent and a liquid bleach additive composition, as described herein, and subsequently contacting said fabrics with said aqueous bath. The term "conventional laundry detergent" refers herein to a laundry detergent composition currently available on the market. Preferably, said conventional laundry detergent comprises at least one surfactant. Said laundry detergent compositions can be formulated as particulates (including powders, pellets, granules, tablets and the like), liquids (liquids, gels, and the like) as well as the forms of detergents based on water-soluble or water-permeable bags. which comprise liquids and / or particulates (as liquid tablets). Suitable particulate detergent compositions for washing clothes are for example DASH powder®, ARIEL tablets®, ARIEL powder® and other products marketed under the trade designations ARIEL® or TIDE®. In a preferred embodiment herein, the conventional laundry detergent is a conventional particulate laundry detergent, more preferably a conventional laundry detergent, globules, granules or tablets for laundry washing. In a preferred embodiment in accordance with the present invention, the conventional laundry detergent as described herein and, the liquid bleach additive composition herein are dissolved or dispersed, preferably substantially dissolved or dispersed, in the aqueous bath formed in the process according to the present invention. By "substantially dissolved or dispersed" is meant herein, at least 50%, preferably at least 80%, more preferably at least 90%, even more preferably at least 95%, even with more preference of at least 98%, and most preferably at least 99%, of said conventional laundry detergent and / or said liquid bleaching additive composition is dissolved or dispersed in the aqueous bath formed in the process of in accordance with the present invention.

The liquid bleach additive composition and the conventional detergent composition can be supplied into the washer by loading the dispenser compartment of the washer with one or both detergents or directly charging the drum of the washer with one or both detergents. More preferably, the liquid bleach additive composition is placed directly into the drum of the washer, preferably using a dosing device, such as a metering ball (such as Vizirette®). More preferably, both the liquid bleach additive composition and the conventional detergent composition are placed inside the drum of the washing machine, preferably suitable dosing devices are used such as dosing balls, dosing meshes, etc. The particulate composition of bleaching additive is preferably supplied to the main washing cycle of the washing machine before, but more preferably at the same time, than the conventional detergent composition. During the processes according to the present invention the liquid bleach additive compositions herein are usually used in dissolved form. By "in dissolved form", it is hereby meant that the liquid bleach additive compositions according to the present invention can be dissolved by the user, preferably in water. Dilution occurs in a washing machine. Such compositions can be diluted up to 500 times, preferably 5 to 200 times and more preferably 10 to 80 times.

Packaging form of the liquid compositions: Depending on the end use contemplated, the compositions herein can be packaged in a variety of packages including conventional bottles. The present invention further includes as a separate embodiment, a kit containing at least two compositions, wherein a first composition comprises an imido-type peroxyacid and optionally a proton source having at least one proton donor acid moiety in water at a pH lower than 7.5, and wherein a second composition comprises a source of protons having at least one acid donor portion of protons in water at a pH of less than 7.5, wherein said compositions when combined comprise at least 0.80 mmole of available protons at a pH of less than 7.5 per gram of the mixed compositions. By "combined" or "mixed" it is meant that the combination of the compositions present in the kit is in a proportion according to the instructions for use or the implicit conditions of use proposed for the kit. For double-compartment packaging, this mixing ratio can be 1: 1. However, other mixing ratios are also contemplated herein. The concentration (in mmoles per gram of the composition) of available protons in a given mixture of compositions is equivalent to the amount in mmoles of 1 M sodium hydroxide (NaOH) which is required to bring the pH of 100 grams of the composition determined at a value of 7.5 and divided by 100, as discussed above. In case the kit of the present invention comprises at least one solid composition, the concentration of available protons is evaluated by dissolving 100 grams of the combined composition in 100 g of demineralized water. Water. In this embodiment of the present invention the at least two compositions herein can be packaged in a double-compartment package or in two separate packages. In addition, one or more of said two compositions can be packaged in a water-soluble package, such as a water-soluble bag (preferably made of a polyvinyl alcohol or acetate bag). The compositions in the kit according to the present invention can be, independently, solid or liquid compositions. The compositions and optional ingredients may be similar to those discussed above. In a highly preferred embodiment, at least one of the compositions present in said kit is a liquid composition having similar properties as described above. Even more preferably, the kit comprises at least two liquid compositions, more preferably two compositions, packaged in a double-compartment package. The invention is further illustrated by the following examples.

EXAMPLES The following examples will further illustrate the present invention. The compositions were made by combining the ingredients listed in the proportions listed (% by weight, unless otherwise indicated). In addition, the compositions contain water and minor components as sufficient for 100%. The following examples are intended to exemplify the compositions according to the present invention, but are not necessarily used to limit or define the scope of the present invention. Compositions 1 II III IV V (% weight) PAP 3.0 2.0 4.0 1.0 5.0 HEDP 0.2 0.1 0.2 0.1 0.2 Citric acid 8.3 0.0 0.0 9.2 4.0 Succinic acid 0.0 7.6 0.0 0.0 5.0 Malonic acid 0.0 0.0 6.8 0.0 0.0 Glutaric acid 0.0 0.0 0.0 0.0 0.0 adipic acid 0.0 0.0 0.0 0.0 0.0 Witconate ÑAS 8® 0.5 1.0 0.0 1.0 0.0 NaXS 0.0 0.0 0.5 0.5 0.5 pH (reduced with NaOH) 1.9 2.5 2.5 2.5 1.9 mmol protons 1.4 1.4 1.4 1.4 1.5 per gram of composition Compositions VI VIII VIII X (% weight) PAP 3.0 5.0 4.0 1.0 3.0 HEDP 0.2 0.2 0.2 0.1 0.2 Citric acid 5.1 13.8 0.0 8.0 11.2 Succinic acid 0.0 0.0 12.8 5.0 0.0 Malonic acid 0.0 0.0 0.0 0.0 0.0 0.0 glutaral acid 0.0 0.0 0.0 0.0 0.0 adipic acid 0.0 0.0 0.0 0.0 0.0 Witconate ÑAS 8® 0.5 0.0 0.0 1.0 0.0 NaXS 0.0 0.5 0.5 0.5 0.5 pH (reduced with NaOH) 2.0 1.5 2.1 1.9 3.0 mmoles of protons 0.8 2.2 2.2 2.4 1.4 per gram of composition Compositions XI XII XIII XIV XV (% by weight) PAP 3.0 2.0 1.0 2.0 2.0 HEDP 0.2 0.2 0.2 0.1 0.2 Citric acid 8.3 8.3 8.3 0.0 0.0 Succinic acid 0.0 0.0 0.0 0.0 0.0 Malonic acid 0.0 0.0 0.0 0.0 0.0 Glutaric acid 0.0 0.0 0.0 0.0 8.6 acid adipic 0.0 0.0 0.0 9.5 0.0 Witconate ÑAS 8® 0.0 0.0 0.0 0.0 0.5 NaXS 0.5 0.5 0.5 0.5 0.0 pH (reduced with NaOH) 1.9 1.9 1.9 2.9 3.0 mmoles of protons 1.4 1.4 1.4 1.4 1.4 per gram of composition Witkonate ÑAS 8® is an alkyl sulfonate available from Witco ACE. BHT is di-tert butyl hydroxytoluene. HEDP is etan 1-hydroxy diphosphonate commercially available from Monsanto under the DEQUEST® series. PAP is phthalimido peroxyhexanóico acid available from Ausimont under the trade name Eureco®. NaXS is sodium xylene sulfonate, available from Rhodia under the trade name Eltesol SX 33®.

Claims (16)

1. NOVELTY OF THE INVENTION
3. A liquid bleach additive composition having a viscosity of up to 5 Pa.s (5000 cP) and / or comprising at least 50% by weight of the total water composition, and further comprising an imide type peroxyacid and a source of protons having at least one donor acid portion of protons in water at a pH of less than 7.5, wherein the composition comprises at least 0.80 mmoles of available protons at a pH of less than 7.5 per gram of the composition. 2. The liquid particulate composition of bleach additive according to claim 1, further characterized in that the imido type peroxyacid is a solid, preformed, solid type, peroxyacid, practically insoluble in water. 3. The liquid particulate composition of bleaching additive according to any of the preceding claims, further characterized in that the imido-type peroxyacid has the general formula:
4. R is a C1-20 alkyl group and wherein A, B, C and D are, independently, hydrogen groups or substituents selected individually from the group comprising alkyl, hydroxyl, nitro, halogen, amine, ammonium, cyanide, carboxylic, sulfate , sulfonate, aldehydes or mixtures thereof. 4. The liquid particulate composition of bleach additive according to any of the preceding claims, further characterized in that the imido-type peroxyacid has the general formula: or wherein R is a C 4 alkyl and n is an integer of 1 to
5. 5. The liquid particulate composition of bleach additive according to any of the preceding claims, further characterized in that the imido-type peroxyacid is an alkanoic peroxyacid of the type I; mido, preferably a peroxyacid alkanoic phthalimido, more preferably the peroxyacid type mido is selected from the group comprising e-phthalimido peroxyhexanoic acid; phthalimido peroxyheptanoic acid; Phthalimido peroxyoctanoic acid; phthalimido peroxinonanoic acid; and phthalimido peroxydecanoic acid; and mixtures thereof, and more preferably e-phthalimido peroxyhexanoic acid (PAP).
6. 6. The liquid bleach additive composition according to any of the preceding claims, further characterized in that the composition comprises from 0.1% to 10%, more preferably from 0.1% to 5% and most preferably from 1% to 5% by weight of the total composition of the peroxyacid type of liquid. The liquid bleach additive composition according to any of claims 1 to 5, further characterized in that the composition comprises from 10% to 40%, more preferably from 15% to 30%, most preferably 20% by weight. 25% by weight of the total composition of the peroxyacid type of liquid. The liquid bleach additive composition according to any of the preceding claims, further characterized in that the source of protons is present in a concentration of at least 0.90 mmol, preferably 1.0 mmol, more preferably 1.1 mmol, more preferably 1.8 mmoles, still more preferably 2.0 mmoles and most preferably 2.5 mmoles of available protons at a pH lower than
7. 7.5 per gram of the composition. 9. The liquid bleach additive composition according to any of the preceding claims, further characterized in that the source of protons is present at a concentration of up to 5 mmoles, preferably up to 4.5 mmoles, more preferably 4 mmoles, more preferably 3.5 mmoles, more preferably 3.0 mmoles, even more preferably 2.7 mmoles of available protons at a pH lower than 7.5 per gram of the composition. 10. The liquid particulate composition of bleach additive according to any of the preceding claims, further characterized in that the source of protons is an organic source of protons selected from the group comprising succinic acid, malonic acidcitric acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, italic acid, isophthalic acid, terephthalic acid, hemimellitic acid, trimellitic acid, trimesic acid, melophanoic acid, prenitic acid, pyrolelitic acid, benzene pentacarboxylic acid, and melitic acid and mixtures of these. 11. The liquid particulate composition of bleach additive according to any of claims 1 to 9, further characterized in that the source of protons is an inorganic proton source selected from the group comprising hydrogen sulfuric acid, and dihydrogen phosphoric acid, and mixtures thereof. these. 12. The liquid particulate composition of bleach additive according to any of claims 1 to 9, further characterized in that the source of protons is selected from the group comprising citric acid, succinic acid, malonic acid, glutaric acid, and adipic acid and mixtures thereof. of these. 13. A process to treat fabric; the process comprises the steps of forming an aqueous bath comprising water, a conventional laundry detergent, preferably a granular laundry detergent, and a liquid bleach additive composition in accordance with the present invention, and subsequently contact the fabrics with the water bath. The process for treating fabrics according to claim 13, further characterized in that a sufficient amount of the bleaching additive particulate composition is added to provide at least 80 mmoles, preferably 100 mmoles, more preferably 130 mmoles, still with more preferably 180 mmoles, most preferably 210 mmoles of available protons at a pH lower than 7.5. 15. A liquid bleach additive composition having a viscosity of up to 5 Pa.s (5000 cps) and / or comprising at least 50% by weight of the total water composition, and further comprises an imido-type peroxyacid and a proton source, wherein the source of protons is selected from the group comprising citric acid present at a level of at least 5.1%; succinic acid present at a level of at least 4.7%; malonic acid present at a level of at least 4.2%; glutaric acid present at a level of at least 5.3%; and adipic acid present at a level of at least 5.9%; and mixtures of these. 16. A kit comprising at least two compositions, wherein a first composition comprises an imido-type peroxyacid and optionally a proton source having at least one proton donor acid moiety in water at a pH below 7.5, and in wherein a second composition comprises a source of protons having at least one acid donor portion of protons in water at a pH of less than 7.5, wherein the compositions when combined comprise at least 0.80 mmoles of available protons at a pH lower than 7.5 per gram of the mixed compositions. 17 A process for treating fabrics; The process comprises the steps of forming an aqueous bath comprising water, a conventional laundry detergent, preferably a granular laundry detergent, and a liquid bleach additive composition formed by at least two compositions of the laundry kit. according to claim 16, and subsequently contacting the fabrics with the aqueous bath. The use of a proton source having at least one donor acid portion of protons in water at a pH of less than 7.5, in a liquid bleach additive composition comprising an imido-type peroxyacid, wherein the composition comprises at least 0.80 mmoles of available protons at a pH of less than 7.5 per gram of the composition to provide an effective bleaching performance on stained fabrics, when used in conjunction with a conventional particulate laundry detergent.