EP2281868A1

EP2281868A1 - Bleaching composition

Info

Publication number: EP2281868A1
Application number: EP09164488A
Authority: EP
Inventors: Giulia Ottavia Bianchetti; Gloria Dicapua; Andrea Esposito; Sara Germana; Vincenzo Guida; Luca Sarcinelli
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 2009-07-03
Filing date: 2009-07-03
Publication date: 2011-02-09

Abstract

The present invention relates to a bleaching composition comprising:
a) a bleach activator having the general formula (I):

wherein R is an alkyl group, linear or branched, containing from about 1 to 11 carbon atoms and LG is a suitable leaving group, and
b) a peroxy carboxylic acid having general formula (II): wherein R is selected from C1-4 alkyl and n is an integer of from 1 to 5.

Description

FIELD OF THE INVENTION

The present invention relates to a bleach additive composition containing a bleach activator and a peroxy carboxylic acid, which can be used to bleach fabrics in conjunction with a conventional granular or liquid laundry detergent.

BACKGROUND OF THE INVENTION

The cleaning of stains known as "bleachable" stains, such as those caused by red wine, coffee, tea or fruit juices, from fabrics, has always constituted a challenge. Due to the presence of chromophores in the stains, the highly coloured bleachable stains require the use of bleaching additives, either alone or in combination with regular laundry detergents. Commonly encountered bleaching compositions suitable for the bleaching of stains on fabrics and hard-surfaces are based on halogen bleaches, especially hypochlorite bleaches. Halogen bleaches which are extremely effective bleaching agents, are however relatively aggressive to fabrics and may cause damages such as loss of tensile strength or loss of colour intensity of the fabric. While colour and fabric damage may be minimised by employing milder oxygen bleaches such as hydrogen peroxide, the bleach performance characteristics of such peroxygen bleaches are much less desirable than those of the halogen bleaching agents.
Particulate bleaching compositions based on oxygen bleaches are typically based on persalt bleaches such as sodium perborate, in its various hydrate forms, or on sodium percarbonate. Such persalt bleaches are sources of hydrogen peroxide when used in aqueous washing conditions. However, such oxygen bleaching compositions are sometimes considered as less efficient than hypochlorite bleach compositions. Typically, to overcome such poor bleaching performance of hydrogen peroxide, persalt bleaches are formulated in particulate compositions with bleach activators. However, it has always been difficult to formulate particulate bleach additive compositions which have excellent bleaching performances.
Faced with achieving a balance between cleaning performance and fabric and/or colour damage, bleaching compositions comprising peroxy carboxylic acids as bleaching agents, have been developed. Such bleaching agents are less aggressive bleach than hypochlorite, yet still provide improved cleaning performance versus the peroxygen bleaching agents currently used in most fully formulated detergent compositions. Liquid additives comprising peroxy carboxylic acid may be either directly applied on stains and soiled fabrics before washing (as a pretreating agent) or added into the laundry machine or laundry solution.
However, despite the apparent suitability of those bleaching agents, it has been found that cleaning performance is not always sufficient to meet consumer expectations, in particular when it relates to removing so-called hydrophilic bleachable stains (such as tea, wine, coffee) and mixed greasy/bleachable stains (such as bacon grease, burnt butter, etc.).
It is therefore an object of the present invention to address the issues mentioned above, namely those of providing improved overall stain removal performance on a wide range of soils, in addition to providing colour and fabric safety.
It has now been found that the combination of a bleach activator and of a peroxy carboxylic acid leads to a surprising improvement in cleaning and in whitening performance as well as on fabrics safety. Another advantage of the compositions of the present invention is that they exhibit also effective stain removal performance on various stains including enzymatic stains and/or greasy stains.
An advantage of the compositions of the present invention is, thus, that the compositions herein are suitable for the bleaching of different types of fabrics including natural fabrics, (e.g., fabrics made of cotton, and linen), synthetic fabrics such as those made of polymeric fibres of synthetic origin (e.g., polyamide-elasthane) as well as those made of both natural and synthetic fibres. For example, the compositions of the present invention herein may be used on synthetic fabrics despite a standing prejudice against using bleaches on synthetic fabrics, as evidenced by warnings on labels of clothes and commercially available bleaching compositions like hypochlorite-containing compositions. The compositions of the present invention have thus the benefit of having excellent cleaning performance while still being safe to fabrics. Another advantage of the compositions according to the present invention is that they can be used in a variety of conditions, i.e., in hard and soft water.

SUMMARY OF THE INVENTION

The present invention relates to a bleaching composition comprising:

a) a bleach activator having the general formula (I):
wherein R is an alkyl group, linear or branched, containing from about 1 to 11 carbon atoms and LG is a suitable leaving group, and
b) a peroxy carboxylic acid having general formula (II):
wherein R is selected from C1-4 alkyl and n is an integer of from 1 to 5.

DETAILED DESCRIPTION OF THE INVENTION

The bleach additive composition

By "bleach additives" it is meant herein, a composition that is used in conjunction with, this means added to the washing machine together with, a conventional laundry detergent, in particular a laundry detergent, in a laundry washing operation.
The bleaching compositions herein are suitable for use in conjunction with a conventional laundry detergent, and in particular with particulate laundry detergents, to treat (stained) fabrics. The terms "additive" or "through-the-wash (bleaching) composition" refer to compositions that are preferably employed in the specific process of treating, preferably bleaching, fabrics as encompassed by the present invention.
Indeed, additive compositions are added together with a conventional laundry detergent (preferably particulate laundry detergent) into a washing machine and are active in the same wash-cycle. By contrast, so-called 'spotter' or 'pretreater' compositions that are applied, mostly undiluted, onto fabrics prior to washing or rinsing the fabrics and left to act thereon for an effective amount of time. Furthermore, so-called 'soakers' or 'rinse-added' compositions are contacted, mostly in diluted form, with fabrics prior or during rinsing of fabrics with water.
The bleach additive compositions herein may be either particulate or liquid compositions. By "particulate" it is meant herein powders, pearls, granules, tablets and the like. Particulate compositions are preferably applied onto the fabrics to be treated dissolved in, an appropriate solvent, typically water.
Alternatively "liquid" bleach additive compositions preferably have a viscosity of up to 5000 cps at 20s^-1 and/or comprise at least 50% by weight of the total composition of water. Liquid bleach additive compositions more preferably have a viscosity of from 50 to 5000 cps at 20 s^-1, still more preferably from 50 cps to 2000 cps, and most preferably from 50 cps to 1200 cps at 20 s^-1 when measured at 20°C using a Carri-Med Rheometer model CSL² 100® (Supplied by TA Instruments) with a 4 cm conic spindle in stainless steal (linear increment from 0.1 to 100 sec^-1 in max. 8 minutes).
Alternatively or additionally (preferably additionally), the liquid bleach additive compositions comprise at least 50%, preferably from 50% to 95%, more preferably 70% to 95%, even more preferably 75% to 95% by weight 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. Formulating the compositions according to the present invention in the acidic pH range contributes to the chemical stability of the additive compositions according to the present invention.
The particulate bleach additive composition herein have a pH measured at 25°C, preferably of at least, with increasing preference in the order given, 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, when diluted into 1 to 500 times its weight of water. Independently, particulate bleach additive composition herein have a pH measured at 25°C, preferably of no more than, with increasing preference in the order given, 12, 11.5, 11, 10.5, 10, 9.5, 9, 8.5 or 8, when diluted into 1 to 500 times its weight of water.
Particulate compositions of the present invention can be made by a variety of methods well known in the art, including dry-mixing, spray drying, agglomeration and granulation and combinations thereof. The compositions herein can be prepared with different bulk densities, from conventional granular products to so called "concentrated" products (i.e., with a bulk density above 600g/l).

Bleach activators

As a first essential ingredient, the compositions according to the present invention comprise bleach activators.
In a preferred embodiment, the bleach activator used in the bleach composition has the general formula:
wherein R is an alkyl group, linear or branched, containing from about 1 to 11 carbon atoms and LG is a suitable leaving group. As used herein, a "leaving group" is any group that is displaced from the bleach activator as consequence of nucleophilic attack on the bleach activator by the perhydroxide anion, i.e. perhydrolysis reaction.
Generally, a suitable leaving group is electrophilic and is stable such that the rate of the reverse reaction is negligible. This facilitates the nucleophilic attack by the perhydroxide anion. The leaving group must also be sufficiently reactive for the reaction to occur within the optimum time frame, for example during the wash cycle. However, if the leaving group is too reactive, the bleach activator will be difficult to stabilize. These characteristics are generally paralleled by the pKa of the conjugate acid of the leaving group, although exceptions to this convention are known. The conjugate acid of the leaving group in accordance with the present invention preferably has a pKa in a range from about 4 to about 13, more preferably from about 6 to about 11, and most preferably from about 8 to about 11.
Preferably, the leaving group has the formula:
wherein Y is selected from the group consisting of SO₃ ^- M⁺, COO^- M⁺, S0₄ ^- M⁺, PO₄ ^- M⁺, PO₃ ^- M⁺. (N⁺R² ₃)X^- and O←N(R² ₂), M is a cation and X is an anion, both of which provide solubility to the bleach activator, and R² is an alkyl chain containing from about 1 to about 4 carbon atoms or H. In accordance with the present invention, M is preferably an alkali metal, with sodium being most preferred. Preferably, X is a hydroxide, methylsulfate or acetate anion.
Other suitable leaving groups have the following formulas
wherein Y is the same as described above and R³ is an alkyl chain containing from about 1 to about 8 carbon atoms, H or R².
While numerous bleach activators as described above are suitable for use in the present bleach composition, a preferred bleach activator has the formula:
wherein R is an alkyl chain, linear or branched, containing from 1 to 11 carbon atoms. More preferably, R is an alkyl chain, linear or branched, containing from 3 to 11, even more preferably from 8 to 11.
Most preferably, according to the present invention, the bleach activator has the formula:
which is also referred to as sodium n-nonyloxybenzene sulfonate (hereinafter referred to as "NOBS").
This bleach activator and those described previously may be readily synthesized by well known reaction schemes or purchased commercially, neither of which is more preferred. Those skilled in the art will appreciate that other bleach activators beyond those described herein which are readily water-soluble can be used in the present bleach composition without departing from the scope of the invention.
Typically, the compositions of the present invention might comprise from 1% to 30% by weight of the total composition of a bleach activators, preferably from 2% to 20% and more preferably from 3% to 10%.
Preferred mixtures of bleach activators herein comprise n-nonanoyloxybenzene-sulphonate (NOBS) together with a second bleach activator having a low tendency to generate diacyl peroxide, but which delivers mainly peracid.
The second bleach activators may include tetracetyl ethylene diamine (TAED), acetyl triethyl citrate (ATC), acetyl caprolactam, benzoyl caprolactam and the like, or mixtures thereof. Indeed, it has been found that mixtures of bleach activators comprising n-nonanoyloxybenzene-sulphonate and the second bleach activators, contribute to further boost particulate soil removal performance while exhibiting at the same time good performance on diacyl peroxide sensitive soil (e.g., beta-carotene) and on peracid sensitive soil (e.g., body soils).

The oxygen bleach

As a second essential ingredient, the compositions according to the present invention comprise oxygen bleach, and more specifically a peroxy carboxylic acid (hereafter referred to as peracid).
Suitable peracids are any of those known in the art. Preferred peracids are those having general formula:
wherein R is selected from C1-4 alkyl and n is an integer of from 1 to 5.
In a particularly preferred aspect of the present invention the peracid has the formula such that R is CH₂ and n is 5 i.e. phthaloyl amino-peroxy caproic acid or PAP. The peracid is preferably used as a substantially water-insoluble solid compound and is available from Solvay/Ausimont under the tradename Euroco®.
The peracid is present may be present at a level in the composition of from 0.1% to 10% more preferably 0.5% to 8% and most preferably 1% to 6%. Alternatively the peracid may be present at a much higher level of for example 10% to 40%, more preferably from 15% to 30%, most preferably from 20% to 25%).

Optional Ingredients

The compositions herein may further comprise a variety of other optional ingredients such as anti-redeposition polymer, surfactant, filers, chelating agents, radical scavengers, antioxidants, stabilisers, builders, dye transfer inhibitor, brighteners, perfumes, pigments, dyes and the like.

Anti-redeposition polymer

The compositions of the present invention may comprise as a highly preferred though option ingredient, an anti-redeposition polymer.
Suitable anti-redeposition polymers include polymeric polycarboxylates and polyacrylates polymers, preferably having a weight average molecular weight of from 1,000Da to 20,000Da. Suitable anti-redeposition polymers include also co-polymers of maleic acid and acrylic acid, preferably having a molar ratio of maleic acid monomers to acrylic acid monomers of from 1:1 to 1:10 and a weight average molecular weight of from 10,000Da to 200,000Da, or preferably having a molar ratio of maleic acid monomers to acrylic acid monomers of from 0.3:1 to 3:1 and a weight average molecular weight of from 1,000Da to 50,000Da.
Further suitable anti-redeposition polymers include cellulose derivatives, for example carboxymethyl cellulose, methylhydroxyethyl cellulose, and mixtures thereof. An example of a suitable carboxymethylcellulose is Finnfix^® BDA, supplied by CPKelco, Arhem, Netherlands. An example of suitable methylhydroxymethyl cellulose is Tylose^® MH50 G4, supplied by SE Tylose GmbH, Wiesbaden, Germany.
Typically, the compositions of the present invention may comprise up to 10% by weight of the total composition of such a soil suspending polyamine polymer or mixtures thereof, preferably from 0.1% to 5% and more preferably from 0.3% to 2%.
The compositions herein may also comprise other polymeric soil release agents known to those skilled in the art. Such polymeric soil release agents are characterised by having both hydrophilic segments, to hydrophilize the surface of hydrophobic fibres, such as polyester and nylon, and hydrophobic segments, to deposit upon hydrophobic fibres and remain adhered thereto through completion of washing and rinsing cycles and, thus, serve as an anchor for the hydrophilic segments. This can enable stains occurring subsequent to treatment with the soil release agent to be more easily cleaned in later washing procedures.
Preferably, the anti-redeposition polymers are polymers of formula A. The polymer A is a polymer according to formula III:
wherein Y is a comonomer or comonomer mixture selected from the group specified below ; R¹ and R² are bleach- and alkali-stable polymer-end groups; R³ is H, OH or C_1-4 alkyl; M is H, alkali metal, alkaline earth metal, ammonium or substituted ammonium; p is not 0, up to 2; and n is at least 10, or mixtures thereof.
In the polymers herein, Y is selected from the group consisting of maleic acid, citraconic acid, itaconic acid, mesaconic acid and salts thereof, and as the first mixtures thereof, monomer, and an unsaturated monocarboxylic acid such as acrylic acid or an alpha -C_1-4 alkyl acrylic acid as second monomer. Preferred polymers of this class are those according to formula I hereinabove, where Y is maleic acid. Also, in a preferred embodiment, R3 and M are H, and n is such that the polymers have a molecular weight of from 1000 to 400 000 atomic mass units, preferably of from 10 000 to 200 000, more preferably of from 30 000 to 70 000.
The alkali-stable polymer end groups R₁ and R₂ in formula I herein above suitably include alkyl groups, oxyalkyl groups and alkyl carboxylic acid groups and salts and esters thereof.
In the above, n, the degree of polymerization of the polymer can be determined from the weight average polymer molecular weight by dividing the latter by the average monomer molecular weight. Thus, for a maleic-acrylic copolymer having a weight average molecular weight of 15,500 and comprising 30 moles % of maleic acid derived units, n is 182 (i.e. 15,500 / (116 x 0.3 + 72 x 0.7).
In case of doubt, weight-average polymer molecular weights can be determined herein by gel permeation chromatography using Water [mu] Porasil® GPC 60 A² and [mu] Bondagel® E-125, E-500 and E-1000 in series, temperature-controlled columns at 40°C against sodium polystyrene sulphonate polymer standards, available from Polymer Laboratories Ltd., Shropshire, UK, the polymer standards being 0.15M sodium dihydrogen phosphate and 0.02M tetramethyl ammonium hydroxide at pH 7.0 in 80/20 water/acetonitrile. Highly preferred polymers for use herein are those in which n averages from 100 to 800, preferably from 120 to 400.
Preferably, the polymer A of the present invention is an acrylic acid/maleic acid copolymer available under the trade name SOKALAN^® CP-5 from BASF. In a preferred embodiment the polymers A of the present invention have a molecular weight of from 20,000 to 100,000.

Surfactants

The compositions of the present invention may comprise as another optional ingredient surfactants or a mixture thereof. The compositions may comprise from 0.01 % to 20%, preferably from 0. 1% to 15% and more preferably from 0.5% to 8% by weight of the total composition of surfactant or a mixture thereof.
Suitable surfactants for use herein include any nonionic, anionic, zwitterionic, cationic and/or amphoteric surfactants or mixture thereof. Particularly suitable surfactants for use herein are nonionic surfactants such as alkoxylated nonionic surfactants and/or polyhydroxy fatty acid amide surfactants and/or amine oxides and/or zwitterionic surfactants like the zwitterionic betaine surfactants described herein after.
Suitable anionic surfactants include alkyl sulfate surfactant. Preferred alkyl sulfate surfactants include water soluble salts or acids of the formula ROSO₃M wherein R is preferably a C₁₀-C₂₄ hydrocarbyl, preferably an alkyl or hydroxyalkyl having a C₁₀-C₂₀ alkyl component, more preferably a C₁₂-C₁₈ alkyl or hydroxyalkyl, and M is H or a cation, e.g., an alkali metal cation (e.g., sodium, potassium, lithium), or ammonium or substituted ammonium (e.g., methyl-, dimethyl-, and trimethyl ammonium cations and quaternary ammonium cations, such as tetramethyl-ammonium and dimethyl piperdinium cations and quarternary ammonium cations derived from alkylamines such as ethylamine, diethylamine, triethylamine, and mixtures thereof, and the like). Typically, alkyl chains of C_12-16 are preferred for lower wash temperatures (e.g., below about 50°C) and C_16-18 alkyl chains are preferred for higher wash temperatures (e.g., above about 50°C).
Suitable anionic surfactants include Alkyl Alkoxylated Sulfate Surfactant. Preferred Alkyl Alkoxylated Sulfate Surfactant include water soluble salts or acids of the formula RO(A)_mSO₃M wherein R is an unsubstituted C₁₀-C₂₄ alkyl or hydroxyalkyl group having a C₁₀-C₂₄ alkyl component, preferably a C₁₂-C₂₀ alkyl or hydroxyalkyl, more preferably C₁₂-C₁₈ alkyl or hydroxyalkyl, A is an ethoxy or propoxy unit, m is greater than zero, typically between about 0.5 and about 6, more preferably between about 0.5 and about 3, and M is H or a cation which can be, for example, a metal cation (e.g., sodium, potassium, lithium, calcium, magnesium, etc.), ammonium or substituted-ammonium cation. Alkyl ethoxylated sulfates as well as alkyl propoxylated sulfates are contemplated herein. Specific examples of substituted ammonium cations include methyl-, dimethyl-, trimethyl-ammonium and quaternary ammonium cations, such as tetramethyl-ammonium, dimethyl piperdinium and cations derived from alkanolamines such as ethylamine, diethylamine, triethylamine, mixtures thereof, and the like.
Exemplary surfactants are C₁₂-C₁₈ alkyl polyethoxylate (1.0) sulfate; C₁₂-C₁₈E(1.0)M; C₁₂-C₁₈ alkyl polyethoxylated (2.25) sulfate; C₁₂-C₁₈E(2.25)M; C₁₂-C₁₈ alkyl polyethoxylate(3.0)sulfate C₁₂-C₁₈E(3.0), and C₁₂-C₁₈ alkyl polyethoxylate (4.0) sulfate C₁₂-C₁₈E(4.0)M, wherein M is conveniently selected from sodium and potassium.
Preferred surfactants for use in the compositions according to the present invention are the alkyl sulfates, alkyl alkoxylated sulfates, and mixtures thereof.
Another preferred surfactant system for use in the compositions according to the present invention are acyl-sarcosinates surfactants.
Suitable nonionic surfactants include compounds produced by the condensation of alkylene oxide groups (hydrophilic in nature) with an organic hydrophobic compound, which may be aliphatic or alkyl aromatic in nature. The length of the polyoxyalkylene group which is condensed with any particular hydrophobic group can be readily adjusted to yield a water-soluble compound having the desired degree of balance between hydrophilic and hydrophobic elements.
Preferred for use in the present invention are nonionic surfactants such as the polyethylene oxide condensates of alkyl phenols, e.g., the condensation products of alkyl phenols having an alkyl group containing from about 6 to 16 carbon atoms, in either a straight chain or branched chain configuration, with from about 4 to 25 moles of ethylene oxide per mole of alkyl phenol.
Preferred nonionic surfactants are the water-soluble condensation products of aliphatic alcohols containing from 8 to 22 carbon atoms, in either straight chain or branched configuration, with an average of up to 25 moles of ethylene oxide per more of alcohol. Particularly preferred are the condensation products of alcohols having an alkyl group containing from about 9 to 15 carbon atoms with from about 2 to 10 moles of ethylene oxide per mole of alcohol; and condensation products of propylene glycol with ethylene oxide. Most preferred are condensation products of alcohols having an alkyl group containing from about 12 to 15 carbon atoms with an average of about 3 moles of ethylene oxide per mole of alcohol.
Other suitable surfactants according to the present invention includes also cationic, ampholytic, zwitterionic, and semi-polar surfactants, as well as nonionic surfactants other than those already described herein, including the semi-polar nonionic amine oxides.

Fillers

The compositions of the present invention may comprise a filler salt as a highly preferred though option ingredient. Suitable filler salts herein are selected from the group consisting of sodium sulfate, sodium chloride, sodium tripolyphosphate "STPP" and the like. Typically, the compositions according to the present invention may comprise from up to 75% by weight of the total composition of a filler salt or a mixture thereof, preferably from 10% to 70 % and more preferably from 30% to 60%.

Chelating agents

The compositions of the present invention may comprise a chelating agent as an optional ingredient. 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%.
Suitable phosphonate chelating agents for use herein may include alkali metal ethane 1-hydroxy diphosphonates (HEDP), alkylene poly (alkylene phosphonate), as well as amino phosphonate compounds, including amino aminotri(methylene phosphonic acid) (ATMP), nitrilo trimethylene phosphonates (NTP), ethylene diamine tetra methylene phosphonates, and diethylene triamine penta-methylene phosphonates (DTPMP). The phosphonate compounds may be present either in their acid form or as salts of different cations on some or all of their acid functionalities. Preferred phosphonate chelating agents to be used herein are diethylene triamine penta methylene phosphonate (DTPMP) and ethane 1-hydroxy diphosphonate (HEDP). Such phosphonate chelating agents are commercially available from Monsanto under the trade name DEQUEST^®.
Polyfunctionally-substituted aromatic chelating agents may also be useful in the compositions herein. See U.S. patent 3,812,044, issued May 21, 1974, to Connor et al . Preferred compounds of this type in acid form are dihydroxydisulfobenzenes such as 1,2-dihydroxy -3,5-disulfobenzene.
Further carboxylate chelating agents to be used herein include salicylic acid, aspartic acid, glutamic acid, glycine, malonic acid or mixtures thereof. Particularly preferred chelating agents to be used herein are amino aminotri(methylene phosphonic acid), di-ethylene-triamino-pentaacetic acid, diethylene triamine penta methylene phosphonate, 1-hydroxy ethane diphosphonate, ethylenediamine N, N'-disuccinic acid, and mixtures thereof.

Brightener

Any optical brighteners, fluorescent whitening agents or other brightening or whitening agents known in the art can be incorporated in the instant compositions when they are designed for fabric treatment or laundering, at levels typically from about 0.05% to about 1.2%, by weight, of the compositions herein.

Processes of treating fabrics

The present invention encompasses a process of treating fabrics which comprises the steps of forming an aqueous bath comprising water, a conventional laundry detergent, preferably a granular laundry detergent, and a bleach additive composition according to the present invention, and subsequently contacting the fabrics with the aqueous bath.
The processes of treating, preferably bleaching, fabrics according to the present invention deliver effective whiteness performance. The process of treating fabrics herein comprises the steps of forming an aqueous bath comprising water, a conventional laundry detergent and a bleach additive composition, as described herein, subsequently contacting the fabrics with the aqueous bath.
By "conventional laundry detergent" it is meant herein, a laundry detergent composition currently available on the market. Preferably, the conventional laundry detergent comprises at least one surfactant. The laundry detergent compositions may be formulated as particulates (including powders, pearls, granules, tablets and the like), liquids (liquids, gels, and the like) as well as detergent forms based on water-soluble or water-permeable pouches comprising liquids and/or particulates (such as "liqui-tabs"). Suitable particulate laundry detergent compositions are for example DASH powder^®, ARIEL tablets^®, ARIEL powder^® and other products sold under the trade names ARIEL^® or TIDE^®.
In a preferred embodiment herein, the conventional laundry detergent is a conventional particulate laundry detergent more preferably a conventional powder, pearl, granule or tablet laundry detergent.
In a preferred embodiment according to the present invention, the conventional laundry detergent as described herein and the 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" it is meant herein, that at least 50%, preferably at least 80%, more preferably at least 90%, even more preferably at least 95%, still more preferably at least 98%, and most preferably at least 99%, of the conventional laundry detergent and/or the bleach additive composition are dissolved or dispersed in the aqueous bath formed in the process according to the present invention.
The bleach additive composition according to the present invention and the conventional detergent composition may be delivered into the washing machine either by charging the dispenser drawer of the washing machine with one or both of the detergents or by directly charging the drum of the washing machine with one or both of the detergents. More preferably the bleach additive composition is directly placed into the drum of the washing machine, preferably using a dosing device, such as a dosing ball (such as the Vizirette^®). Even more preferably the bleach additive composition and the conventional detergent composition are both placed into the drum of the washing machine, preferably using suitable dosing devices such as dosing balls, dosing nets etc. The bleach additive composition is preferably delivered to the main wash cycle of the washing machine before, but more preferably at the same time as the conventional detergent composition.
During the processes according to the present invention the bleach additive composition herein is typically used in dissolved form. By "in dissolved form", it is meant herein that bleach additive compositions, especially particulate bleach additive compositions, according to the present invention may be dissolved by the user, preferably in water. The dissolution occurs in a washing machine. The compositions can be dissolved up to 500 times its own weight, preferably from 5 to 350 times and more preferably from 10 to 200 times.
The compositions herein can be packaged in a variety of containers including conventional boxes, tubs, bottles etc.

Examples

The following compositions are prepared:

Ingredient	I % wt	II % wt	III % wt	IV % wt	V % wt
¹PAP (Granular)	56	56	40	50	15
²NOBS	13.3	13.3	10	15	7
³Perfume	0.2	0.2	0.2	-	0.4
⁴Polymer	30.5	10	25	15	2
⁵HEDP (Granular)	-	0.3	-	2	0.4
⁶Brightener	-	0.2	-	0.5	0.2
⁷Blown Powder	-	15	20	-	38
Filler - Sodium Sulfate	-	3	3.8	11.5	21
Others	-	2	1	6	16

¹PAP is phthaloyl amino-peroxy caproic acid, Eureco®, available from Solvay.
²NOBS is sodium n-nonyloxybenzene sulfonate.
⁴Polymer is polyacrylate co-polymer, Sokalan CP5®, available from BASF.
⁵HEDP is hydroxyethane diphosphonate available from Dow Chemical.
⁶Brightener is Tinopal® CBS-X available from Ciba Specialty Chemicals, (Switzerland).
⁷Blown Powder is 50% zeolite, 38% sodium sulfate, 8% ⁴Polymer, 3% sodium alkyl benzene sulphonate, and balance moisture.
Others may include enzymes, coloured speckles, additional polymer.

The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as "40 mm" is intended to mean "about 40 mm".

Claims

A bleaching composition comprising :
a) a bleach activator having the general formula (I):
wherein R is an alkyl group, linear or branched, containing from about 1 to 11 carbon atoms and LG is a suitable leaving group, and

b) a peroxy carboxylic acid having general formula (II):
wherein R is selected from C1-4 alkyl and n is an integer of from 1 to 5.
The bleaching composition according to claim 1 wherein the leaving group has the formula :
wherein Y is selected from the group consisting of SO₃ ^- M⁺, COO^- M⁺, SO₄ ^- M⁺, PO₄ ^- M⁺, PO₃ ^- M⁺. (N⁺R² ₃)X^- and O←N(R² ₂), M is a cation, X is an anion and R² is an alkyl chain containing from 1 to 4 carbon atoms or H ; preferably, M is sodium and X is a hydroxide, methylsulfate or acetate anion.
The bleaching composition according to any of the preceding claims wherein the bleach activator has the formula :
wherein R is an alkyl chain, linear or branched, containing from 1 to 11, preferably from 3 to 11.
The bleaching composition according to claim 1 wherein the bleach activator has the formula :
The bleaching composition according to any of the preceding claims wherein the compositions comprise from 1% to 30%, preferably from 2% to 20% and more preferably from 3% to 10%, by weight of the total composition, of the bleach activators.
The bleaching composition according to any of the preceding claims wherein, in the peroxy carboxylic acid of the general formula (II), R is CH₂ and n is 5.
The bleaching composition according to any of the preceding claims wherein the peroxy carboxylic acid is present at a level of from 1% to 70%, more preferably from 10% to 60%, most preferably from 20% to 50% by weight of the total composition.
The bleaching composition according to any of the preceding claims which further comprises an anti-redeposition polymer, preferably which is according to formula I:
wherein Y is a comonomer or comonomer mixture selected from the group consisting of maleic acid, citraconic acid, itaconic acid, mesaconic acid and salts thereof; R¹ and R² are bleach- and alkali-stable polymer-end groups; R³ is H, OH or C_1-4 alkyl; M is H, alkali metal, alkaline earth metal, ammonium or substituted ammonium; p is not 0, up to 2; and n is at least 10, or mixtures thereof.
The bleaching composition according to claim 8 wherein the anti-redeposition polymer has a molecular weight of from 1 000 to 400 000, preferably of from 10 000 to 200 000, more preferably of from 30 000 to 70 000.
A process of treating fabrics which comprises the steps of:
i) forming an aqueous bath comprising water, a conventional laundry detergent, and a bleach additive composition according to any of the preceding claims, and

ii) subsequently contacting the fabrics with the aqueous bath.