WO1995006710A1

WO1995006710A1 - Bleach catalyst composition

Info

Publication number: WO1995006710A1
Application number: PCT/GB1994/001904
Authority: WO
Inventors: Andrew Paul Chapple; Jayne Elisabeth Nation; William Derek Emery; Hermien Willemyn Plomp; Craig Steven Cicciari; Karla Jean Cicciari; Marten Robert Pieter Van Vliet; Cornelis Bernard Donker; Clemens Osman Monir
Original assignee: Unilever Plc; Unilever N.V.
Priority date: 1993-09-03
Filing date: 1994-09-02
Publication date: 1995-03-09
Also published as: AU7506694A; TR28071A

Abstract

A bleach catalyst composition in the form of non-friable composite granules comprising: i) a manganese complex catalyst being one of three defined formulae herein; ii) a hydrophobic binding agent, preferably selected from silicone oils, C11-C18 fatty acids, C11-C18 fatty acid soaps, C11-C18 fatty esters, tri-, di- and monoglycerides, waxes, solid hydrocarbons and mixtures thereof; and iii) a non-delinquescent or non-hygroscopic soluble core material such as sodium bicarbonate. The granular, manganese complex-based bleach catalyst comosition may be incorporated in detergent and/or bleaching compositions, with good resulting stability and homogeneity of distribution.

Description

Bleach Catalyst Composition

FIELD OF THE INVENTION

This invention relates to a bleach catalyst composition. In particular, it relates to a stable bleach catalyst composition, comprising a manganese complex as the active bleach catalyst, in a form suitable for use in or in conjunction with a detergent and/or bleach composition.

BACKGROUND OF THE INVENTION AND PRIOR ART Previously, manganese complexes have been proposed as catalysts to enhance the activity of peroxygen bleaches such as hydrogen peroxide, hydrogen peroxide liberating or generating compounds and inorganic and organic peroxyacids. Such complexes include manganese- gluoconate complexes, as described in EP-A-237 111, and manganese polyol complexes, as described in EP-A-443 651.

The effective amount of such complexes required in detergent and/or bleach compositions is very small, of the order of hundredths of a percent. Problems associated with the use of such small quantities include achieving an accurate dosage and homogeneous distribution of the complex throughout the composition. Inhomogenuity in the distribution of the complex may result in an inconsistent performance of the detergent and/or bleach composition.

Good distribution of the complex in a composition may be achieved by spraying a solution thereof, onto a base detergent formulation. However, this has its disadvantages in that direct contact between the manganese complex and other components present, for example nonionic detergent active and peroxygen bleaching agent, may result in a reduction in the level of these active components as a result of adverse redox reactions.

Another option would be to mix pure crystals of the manganese complex with the base detergent and/or bleach formulation. However, this may also result in interactions between individual components with consequential losses in levels of active materials.

In particular, interaction between the manganese complex and a peroxide bleach may result in rapid decomposition of the bleach during storage.

A further problem which may arise when manganese is incorporated in a base formulation is the formation of brown inactive manganese dioxide during storage and/or upon powder dissolution. Previously, in order to overcome such problems, it has been proposed to form heavy metal complexes into agglomerates prior to addition to a detergent base formulation. An example is US Patent 4 626 373 which teaches manganese complexes, comprising Mn(II) and a ligand such as ethylenediamine tetraacetic acid or diethylene triamine pentaacetic acid, may be protected by encapsulating them in a matrix of a water-soluble or water-dispersible material.

The present invention is particularly concerned with a highly reactive manganese complex catalyst, as described in EP-A-O 458 397 and EP-A-O 458 398, and derivatives thereof.

EP-A-O 544 440 is concerned with such manganese complex catalysts and suggests overcoming the aforementioned problems by forming non-friable composite granules comprising the complex, a binding agent such as a polymer, a silicate or fatty acid/soap mixture and, optionally, an inert salt such as a chloride or carbonat .

Another suggestion, taught by our copending International Patent Application PCT/EP94/00640 (corresponding to UK Patent Application 9305598.6) involves forming granules comprising the complex; a - A -

carrier material selected from zeolite, alkali metal sulphate, citric acid, succinic acid and starch; and a binding agent selected from water-soluble non- oxidisable polymers, alkalimetal silicates and saturated fatty acid soap.

SUMMARY OF THE INVENTION

We have now found granules comprising the manganese complex catalyst, a hygrophobic binding agent and a non-deliquescent or non-hydroscopic soluble core overcome at least some of the disadvantages associated with known systems and show good storage stability.

Accordingly the present invention provides a bleach catalyst composition in the form of non-friable composite granules, characterised in that the granules comprise:

i) a manganese complex catalyst selected from :-

(a) dinuclear manganese complexes of formula:-

wherein each Mn is manganese which may independently be in the III or IV oxidation state; each X independently represents a coordinating or bridging species selected from the group consisting of H₂0, 0₂ ^2", 0²", OH", H0₂", SH^", S²", >S0, Cl", N³\ SCN", NH₂", NR, R^a ₃S0₄\ R"S0₃ ^" and R^aC00" where R^a is selected from H, alkyl, aryl, substituted alkyl and substituted aryl and R^bC00", where R^b is selected from alkyl, aryl, substituted alkyl and substituted aryl; z denotes the charge of the complex and is an integer which can be zero, positive or negative; Y is a monovalent or multivalent counter-ion, leading to charge neutrality, which is dependent upon the charge z of the complex; q = z/[charge Y] ; and

L is a ligand which is a macrocyclic organic compound of formula (I) :-

,-[NR³ - <CR^l(R²) _t].-, (I)

wherein t is an integer from 2 to 3; s is an integer from 3 to 4, u is 0 or 1; R¹, R² and R³ are each independently selected from H, alkyl, aryl, substituted alkyl and substituted aryl; (b) dinuclear manganese complexes of formula:-

wherein each Mn is manganese which may independently be in the III or IV oxidation state; each X independently represents a coordinating or bridging species selected from the group consisting of H₂0, 0₂ ^2", 0²", OH^', H0₂", SH\ S^2_, >S0, Cl", N³\ SCN^", NH₂ ^", NR, R^β ₃S0₄-, R^aS0₃- and R^aC00" where R^a is selected from H, alkyl, aryl, substituted alkyl and substituted aryl and R^bC00", where R^b is selected from alkyl, aryl, substituted alkyl and substituted aryl; z denotes the charge of the complex and is an integer which can be zero, positive or negative; Y is a monovalent or multivalent counter-ion, leading to charge neutrality, which is dependent upon the charge z of the complex; q = z/[charge Y] ; and

L is a ligand which comprises two species of formula (II) :-

wherein t is an integer from 2 to 3; s is an integer from 3 to 4, u is 0 or 1; R¹, R² and R⁴ are each independently selected from hydrogen, alkyl, aryl, substituted alkyl and substituted aryl, with the proviso that a bridging unit R⁵ is formed by one R⁴ unit from each ligand where R⁵ is the group (CR⁶R⁷)_n-(D)_p-(CR⁶R⁷)_B where p is 0 or 1; D is selected from a heteroatom such as oxygen and NR⁸ or is part of an aromatic or saturated homonuclear or heteronuclear ring, n is an integer from 1 to 4; m is an integer from 1 to 4; with the proviso that n + m < 4;

R⁶ and R⁷ are each independently selected from H, NR⁹ and OR¹⁰, alkyl, aryl, substituted alkyl and substituted aryl; and R⁸, R⁹, R¹⁰, are each independently selected from H, alkyl, aryl, substituted alkyl and substituted aryl;

(c) mononuclear manganese complexes of formula:-

[L Mn X_p]^zY_q

wherein Mn is manganese in the II, III or IV oxidation state; each X represents a coordinating species independently selected from OR¹¹, where R¹¹ is a Ci-Cz_o radical selected from the group consisting of alkyl, cycloalkyl, aryl, benzyl and radical combinations thereof or at least two R¹¹ radicals may be connected to one another so as to form a bridging unit between two oxygens that coordinate with the manganese, Cl", Br^~, I", F^", NCS", N₃-, I₃-, NH₃, OH^", 0₂ ²\ H00^", H₂0, SH, CN^",

OCN" , S₄ ^2~, R^aC00" , R^aS0₃" , where R^a is selected from H, alkyl , aryl , substituted alkyl and substituted aryl and R^bCOO where R^b is selected from alkyl or aryl, substituted alkyl and substituted aryl and mixtures thereof; p is an integer from 1 to 3; z denotes the charge of the complex and is an integer which can be positive or negative;

Y is a onovalent or multivalent counter-ion, leading to charge neutrality, which is dependent upon the charge z of the complex; q = z/[charge Y] ; and L is a macrocyclic organic compound of formula (I) as hereinbefore defined; ii) a hydrophobic binding agent; and iii) a non-deliquescent or non-hygroscopic soluble core material.

DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS

Examples of preferred ligands of formula (I) include 1,4,7-triazacyclononane (TACN); l,4,7-trimethyl-l,4,7- triazacyclononane (1,4,7- Me₃TACN); 2-methyl-l,4,7- triazacyclononane (2-MeTACN); 1,2,4,7-tetramethyl-

1,4,7-triazacyclononane (1,2,4,7-Me₄TACN); 1,2,2,4,7- pentamethyl-l,4,7-triazacyclononane (1,2,2,4,7- Me₅TACN); 1,4,7-trimethyl-2-benzyl-l,4,7- triazacyclononane; and l,4,7-trimethyl-2-decyl-l,4,7- triazacyclononane. Especially preferred is 1,4,7- trimethyl-1,4,7-triazacyclononane.

An example of a preferred ligand which comprises two species of formula

,-[NR⁴ - (CR^R^ ,

1 is 1,2-bis (4,7-dimethyl-l,4,7,triaza-1-cyclononyl) ethane.

The aforementioned ligands may be synthesised by the methods described in K Wieghardt et al. , Inorganic Chemistry 1982, 21, page 3086 et seq, Inorganic

Chemistry, 1985,24,page 1230 et seq, and J. Chem. Soc, Chem. Comm. , 1987, page 886, incorporated herein by reference.

The type of counter-ion Y for charge neutrality is not critical to the activity of the complex and can be selected from, for example, chloride; sulphate; nitrate; methylsulphate; surfactant-anions, such as the long-chain alkylsulphates, alkylsulphonates, alkylbenzenesulphonates, tosylate; trifluormethylsulphonate; perchlorate (C10₄"), BPh₄" and

PF₆"; with PF₆ ^", S0₄ ²" and C10₄" being preferred.

When the manganese complex catalyst is a dinuclear manganese complex, preferred complexes are those in which X is either CH₃C00" or 0²' or mixtures thereof. Most preferred are those complexes in which each X is 0^2" and manganese is in the IV oxidation state.

Dinuclear manganese complexes are further described in EP-A-O 458 397 and EP-A-O 458 398, the disclosures of both of which references are incorporated herein by reference.

Mononuclear complexes are further described in EP-A-O 549 272 and US Patent 5194416, the disclosures of both of which references are incorporated herein by reference. By "hydrophobic" binding agent is meant the water content thereof is less than about 0.5% after equilibration at a temperature of 37^βC and humidity of 70%. The water content is defined as the weight loss in the temperature range 30 to 135^βC as measured by Thermogravimetric Analysis (TGA).

Examples of suitable hydrophobic binding agents include silicone oils, C_u to C₁₈ fatty acids, C_u to C₁₈, including mixed chain, fatty esters, and particularly ceto stearyl stearate, tri-, di- and monoglycerides, waxes and solid hydrocarbons and mixtures thereof.

C_u to C₁₈ fatty acid soaps may also be used.

An especially preferred binding agent is ceto stearyl stearate or a mixture of ceto stearyl stearate and C_n to C₁₈ fatty acid or soap.

A bleach catalyst composition formed with such a mixed binder system shows good storage stability. Furthermore, its low temperature bleach performance is very good and the percentage of residues remaining after a wash process is very low.

By "non-deliquescent" soluble core material is meant a material which is not deliquescent under atmospheric conditions of at least 37°C and 70% RH and, preferably, 37^βC and 80% RH.

By "non-hygroscopic" soluble core material is meant a material which is not hygroscopic under atmospheric conditions of at least 37°C and 70% RH and, preferably, 37°C and 80% RH. Suitable materials include sodium bicarbonate, magnesium and potassium nitrates, magnesium sulphate and mixtures thereof.

Without being bound by theory, the good storage stability shown by the granules according to the invention is thought to be due to the fact that the hydrophobic binding agent and non-deliquescent or non- hygroscopic soluble core material control the moisture take up of the granules to below a level where it may affect stability.

If the granules according to the invention are to be used in a detergent formulation with a large proportion of nonionic surfactant such as about 20% by weight it is preferable that the binding agent is also insoluble in such materials. In such instances, ceto stearyl stearate and silicone oils are particularly preferred.

The granules of the invention preferably comprises from about 0.5 to about 20%, more preferably from about 1 to about 15%, by weight of the manganese complex catalyst, from about 5 to about 90% by weight of the non- deliquescent or non-hygroscopic soluble core material and from about 5 to about 91% by weight of the hydrophobic binding agent.

Preferably granules according to the invention will also comprise an inert solid material, preferably in an amount of from about 5 to about 80% by weight, more preferably from about 10 to about 50% by weight. By "inert" is meant the solid is chemically inert to reaction with other components of the granule. Preferred inert materials include zeolites, silicas such as Gasil, Aerosil and Sorbosil (trade marks); clays such as Kaolin; alumina; titanium dioxide; and mixtures thereof. It is also possible to use a combination of materials such as zeolite neutralised with citric acid. Preferably, the inert solid material is also insoluble in water.

Preferably, the granules according to the invention will also comprise a pigment, in order to improve the colour of the resulting product, and especially to render its colour as white as possible. Titanium dioxide is a particularly preferred pigment, and may be employed at any suitable level such as to give the desired product colour, e.g. up to about 30% by weight of the granules, more preferably from about 0.5 to about 10% by weight.

In many cases, however, the whiteness of the product may be further improved by use of a second pigment, especially a blue pigment, in combination with the titanium dioxide. Examples of suitable blue pigments are widely available commercially and well known in the art, such as for example Disperse Blue 69-0007 ex BASF (a C.I. pigment Blue 15:1, containing dipropylene glycol) or Colanyl-Blue B2G 100 ex Hoechst (a C.I. pigment Blue 15.3 in an aqueous propanediol dispersion).

The pH of the granules according to the invention is preferably within the range from about pH 4.5 to about 8.5. This is the pH, measured with an electrode, of a solution of 10% by weight of the granules in water, which solution has been stirred vigorously for ten minutes.

Preferably the manganese catalyst within the granules is of an average particle size as small as possible, preferably below about 250 μm, for proper distribution and to ensure fast delivery thereof to the wash, though particles which are too small may cause handling problems during the granulation process. A preferred and optimum manganese catalyst particle size is within a range of between about 50 and about 150 μm.

Manganese catalyst particles larger than 150μm may give distribution problems and are more difficult to granulate, whereas particles smaller than 50μm may cause handling problems and excessive granule colouration.

Granule growth control is generally necessary in order to ensure the composite granules are of the same approximate size and bulk density as the main detergent or cleaning powder into which they are incorporated, so as to avoid segregation by percolation or by floating.

Percolation, i.e. bringing the bleach catalyst composite granules to the bottom of a detergent powder batch, pack etc., may occur during and after mixing by vibration, handling and aeration, and will specifically happen with granules which are too small and/or have too high a density. Preferably the granules will have a particle size in the range from about 150 to about 1500μm, most preferably from about 350 to about lOOOμm. Floating will happen specifically with granules which are too large and too light. Both phenomena should generally be avoided, because they introduce errors in amounts dosed to a washing machine.

The bulk density and size of the composite granules can be controlled via the composition, the process conditions or both, as is known in the art. The composite granules of the invention can be prepared by any of the conventional and known granulation techniques, such as using a pan-granulator, fluidised bed, Schugi mixer, Lodige ploughshare mixer, rotating drum and other low energy mixers; by compaction, including extrusion and tabletting optionally followed by pulverising and grinding; when melt binding agents are used by prilling and pastilling using a Sandvik Roto Former; and by a high shear-energy process using a high-speed mixer/granulator equipment having both a stirring action of high energy and a cutting action. Examples of such high-speed mixer/granulator equipment are the Fukae (Trade Mark) FS-G mixer manufactured by Fukae Powtech Kogyo Co. Japan. Other mixers usable in the process of the invention include the Diosna (Trade Mark) V series ex. Dierks & Sohne, Germany; the Pharma Matrix (Trade Mark) ex T K Fielder Ltd England; the Fuji (Trade Mark) VG-C Series ex Fuji Sangyo Co. Japan; and the Roto (Trade Mark) ex Zanchette & Co. S.r.l. Italy. Beside batch equipment, it is also possible to use a high speed mixer/granulator such as the Lδdige Recycler.

The present invention also provides a detergent composition comprising non-friable composite granules comprising a manganese complex catalyst as hereinbefore defined, a hydrophobic binding agent and a non- deliquescent or non-hydroscopic soluble core material.

The detergent composition according to the invention may further contain ingredients commonly present in such compositions. They include surface active materials including soaps, synthetic anionic, nonionic, cationic and zwitterionic detergent surfactants and mixtures thereof, preferably present in a total amount of from 0.5 to about 50% by weight, more preferably from about 1 to about 40% by weight, most preferably from about 4 to about 25% by weight. If the composition contains both anionic and nonionic surfactant, it is preferred that the nonionic surfactant is present in excess amount. Specific examples of detergency active materials suitable for use in detergent compositions of the invention are given for example in EP-A-0458397, EP-A-0458398 and EP- A-0549272 referred to hereinabove.

The present invention further provides a bleaching composition comprising a granular bleach catalyst composition as defined above according to the primary aspect of the invention, together with a bleaching agent. By virtue of its optionally further containing one or more detergency active materials, the bleaching compositions may also be a detergent composition as defined above.

Bleaching agents present in bleaching compositions of the invention include peroxy compound bleaches such as hydrogen peroxide, hydrogen peroxide liberating compounds, hydrogen peroxide generating systems, peroxyacids and their salts, peroxyacid bleach precursor systems and mixtures thereof. Hydrogen peroxide sources include alkali metal peroxides, organic peroxide bleaching compounds and inorganic persalt bleaching compounds such as alkali metal perborates, percarbonates, perphosphates and persulphates. Specific examples of bleaching agents suitable for use in the bleaching compositions of the invention are given for example in EP-A-0458397, EP-A- 0458398 and EP-A-0549272 referred to hereinabove.

Bleach precursors are well known in the art and include N,N,N',N' tetraacetyl ethylene diamine (TAED) and quaternary ammonium substituted peroxyacid precursors. Amongst the group of suitable peroxyacids is included N,N'-phthaloylaminoperoxy caproic (PAP).

The amount of bleaching agent present in bleaching compositions of the invention may vary according to the material(s) used and the bleaching system employed, and also the level of bleaching which it is desired to effect. Generally, however, a bleaching agent or bleaching agent system in an amount of from about 0.5 to about 50% by weight of the composition may be used, more preferably from about 1 to about 40% by weight. Specific examples of suitable amounts of various types of bleaching agent for use in bleaching compositions of the invention are given in for example EP-A-0458397, EP-A-0458398 and EP-A-0549272 referred to hereinabove.

In the above bleaching and/or detergent compositions the bleach catalyst of the invention is employed preferably in such an amount as to provide the desired level of manganese complex catalyst in the wash liquor. When the dosage of the detergent/bleach composition is relatively low, e.g. about 1 and 2 g/1 as used by consumers in Japan and the USA, respectively, then the Mn content in the formulation is preferably selected to be from about 0.001 to about 1.0%, preferably from about 0.005 to about 0.50%. At higher product dosages as used for example by European consumers, the Mn content in the formulation is preferably selected to be from about 0.0005% to about 0.25%, preferably from about 0.001 to about 0.5% (or more preferably to about 0.1%). Typically, the bleach catalyst composition may be present in detergent and/or bleaching compositions of the invention in an amount of from about 0.01 to about 0.1% by weight, more preferably from about 0.02 to about 0.08% by weight. Other ingredients present in detergent or detergent bleach compositions of the invention may include detergency builders such as aluminosilicates, in particular zeolites, e.g. zeolite A, B, C, X and Y types, as well as zeolite MAP as described in EP-A- 0384070; and precipitating builders such as sodium orthophosphate and sodium carbonate. Such builders are preferably present in an amount from about 5 to about 80% by weight, more preferably from about 10 to about 50% by weight. Other typical ingredients may include enzymes, fluorescent agents, multifunctional polymers, stabilising agents such as ethylene diamine tetraacetate (EDTA) and polyphosphonic acid derivatives (e.g. Dequest (trade mark) ).

Bleach and detergent bleach compositions of the invention can be used to bleach stained substrates by contacting the substrate in an aqueous medium with the composition.

The invention will now be further illustrated by the following non-limiting examples.

EXAMPLES

In these examples a manganese complex of formula III was used

Step (I) SYNTHESIS OF

[Mn₂ ^I11(μ-0)₁(μ-OAc)₂(Me₃-TACN₂] (C10₄)₂. (H₂0)

All solvents were degassed (first a vacuum was applied over the solvent for 5 minutes and subsequently argon gas was introduced; this procedure was repeated three times) prior to use (to exclude all oxygen, which oxidizes Mn¹¹ to Mn^IV and caused the formation of Mn^ιυ0₂). The reaction was carried out at room temperature, under argon atmosphere, unless otherwise stated.

In a 25 ml round-bottomed flask, equipped with a magnetic stirrer, 500 mg (2.91 mmol) 1,4,7-trimethyl- 1,4,7-triazacyclononane was dissolved in 15 ml ethanol/water (85/15). This gave a clear, colourless solution (pH >11). Then 0.45 g (1.80 mmol) Mn^JII0AC₃.2ag was added and a cloudy, dark brown solution obtained. After the addition of 1.00 g (7.29 mmol) NaOAc.3aq, the pH fell to 8. About 15 drops of 70% HC10₄ solution were added to adjust the pH of the reaction mixture to 5.0. After addition of 1.50 g (12.24 mmol) NaC10₄, the colour of the reaction mixture changed from brown to red within about 30 minutes.

Then the reaction mixture was allowed to stand for one week at room temperature and the product precipitated in the form of red crystals. The resulting precipitate was filtered over a glass filter, washed with ethanol/water (85/15) and dried in a dessicator over KOH.

Step II: SYNTHESIS OF

[Mn₂ ^IV(μ-0)₃(Me₃-TACN)₂](PF₆)₂H₂0 (III)

This complex was prepared as follows.

In a 50 ml round-bottomed flask, equipped with a magnetic stirrer, 661.4 mg of the material from step (I) (0.823 mmol crystals were pulverised, giving a purple powder) was dissolved in 40 ml of an ethanol/water mixture (1/1). After a five-minute ultrasonic treatment and stirring at room temperature for 15 minutes, all powder had dissolved, giving a dark-red coloured neutral solution. 4 ml of triethylamine was added and the reaction mixture turned to dark-brown colour (pH >11). Immediately 3.55 g (21.12 mmol) of sodium hexafluorophosphate (NaPF₆) was added. After stirring for 15 minutes at room temperature, in the presence of air, the mixture was filtered removing some manganese dioxide, and the filtrate was allowed to stand overnight. A mixture of Mn0₂ and red crystals was formed. The solids were collected by filtration and washed with ethanol. The red crystals (needles) were isolated by adding a few ml of acetonitrile to the filter. The crystals easily dissolved, while Mn0₂, insoluble in acetonitrile, remained on the filter. Evaporation of the acetonitrile solution resulted in the product as red flocks.

In the examples the composition of the base detergent powder used was:

% by weight

Coco PAS^* 14.4 ethoxylated nonionic surfactant 14.4 (3E0/7E0 mixture (56/44%))

Zeolite 4A 30.0

Sodium carbonate 15.0

Fluorescer 0.1

Sodium Silicate 10.0

Minors + moisture to 100%

primary alcohol sulphate derived from coconut oil

Experimental Storage Tests Storage experiments were carried out in open topped glass vessels containing 15.68g of detergent powder A, 3.2g of sodium perborate monohydrate (ex Degussa), Dequest 2047^*** granules (ex Monsanto) and lg of bleach catalyst granules described in examples 1, 2 or 3. The vessels were stored at 37"C/70% RH.

The storage stability of all the granules was assessed visually by estimating the percentage of the bleach catalyst granules which had discoloured (from pink to brownish/black). Granules were not considered to be storage stable, if, from a visual assessment, it appeared that more than about 60% of the granules had changed colour after a storage period of 6 weeks.

The brownish/black colour is considered to be characteristic of the manganese complex catalyst in the granules which have, through redox reactions, been converted into an inactive form. The granules described in examples 1 to 3 below were prepared by granulating together in a Fukae FS-G mixer, with a jacket temperature of 50^βC, the individual components. Solid and liquid components were added to the mixer at temperatures of 20^CC and 60-70°C respectively. The resultant granules were sieved to remove the fractions which were < 300 microns and >1400 microns.

'Dequest' is a Trademark for polyphosphonates ex Monsanto.

Composition % Water Colour content of binder

Example

1 160g Mn catalyst

(III)

3.0kg Gasil 200 TP silica (ex Crosfield) pale

3.0kg sodium pink bicarbonate 1

(average particle size 50 microns) 1 1

2.0kg ceto stearyl <0.1 | stearate 1

2 160g Mn catalyst

(III)

3.0kg Gasil 200 TP silica (ex Crosfield)

3.0kg sodium bicarbonate

(average particle pale size 50 microns) pink

2.0kg silicone oil <0.1

3 160g Mn catalyst comparative (III)

3.0kg of Gasil 200 TP silica (ex Crosfield) 3.0kg sodium bicarbonate 0.86 pale

(average particle pink size 50 microns)

2.0kg of a C₁₂/C₁₈ fatty acid/soap mixture^*

# Weight loss was measured in a Perkin Elmer TGA7 under an atmosphere of flowing nitrogen (ml/min) using a temperature ramp rate of 5^βC per minute.

70% C₁₂ fatty acid/30% C_lβ fatty acid which is 30% neutralised with sodium hydroxide. This is prepared by mixing the aforementioned fatty acids with the required amount of a 50% sodium hydroxide solution. The latter is added slowly and with intensive mixing.

The resultant clear liquid solidifies in the range 40-80^βC.

Storage Results

Example

1 After 6 weeks <60% granules judged to have discoloured.

2 After 8 weeks <50% granules judged to have discoloured.

3 After 3 weeks >60% granules judged to have discoloured.

Example 4

A mixed binder granule was prepared by premixing a manganese catalyst of formula III (60g) with Gasil 200 TP silica (540g) and sodium bicarbonate (800g) for 5 seconds in a Eirich Intensive Mixer Type R02E.

A melt of sodium palmitate-stearate (E G. R Technical

Grade) (70g), palmitic-stearic acid (117g), lauric acid (Prifac 2920 ex Unichema) (114g), sodium laurate (69g) and cetostearylstearate (Kemfluid 211) (158g) was added to the aforementioned premix in three batches. In each case, after addition to the melt the product was mixed for 20 seconds.

Thereafter the resulting product was cooled by cool aire and granules with a particle size range of 200 to 2000μm obtained. (The Eirich mixer consists of a mixing tool (totating counter clockwise) and set at a speed of 1550rpm and a rotating pan (rotating clockwise) set at a speed of 46 rpm. )

The granule (granule 4) had the following composition:

% bv weight

Mn Catalyst 3

Silica 28

Na bicarbonate 42

Cetostearylstearate 8

Lauric acid 6

Sodium stearate 4

Stearic acid 6

Sodium laurate 4

A further granule according to the invention by containing only a single binder was prepared according to the method described in examples 1 to 3. The granule (4a) had the composition:

% bv weight

Mn Catalyst 2

Silica 26

Na bicarbonate 40

Cetostearylstearate 31

Ti0₂ 1

i) Washing Experiments

Both granules (particles sizes range 500-710μm) were added to separate batches of a detergent composition to give a product with a formulation of:- % bv weight

PAS 5.8 ethoxylated nonionic surfactant

2E0 7.4

7E0 5.8

Zeolite 36

Soap 2

Sodium carbonate 1.0

SCMC 0.9

Fluorescer 3.0

Silicate 2.9

Mn granule 2.4

TAED 4.8

Sodium percarbonate 20.5

Dequest 0.4

Minors & moisture to 100%

The bleach performance of the granule was examined by washing a number of stained test cloths at 20^βC with the aforementioned composition dosed at a level of 87 grams per litre in a AEG Lavamat washing machine.

After rinsing the test cloths were dried in a tumble drier. The reflectance (R₄₆₀,) was measured before and after the washing process.

The following results were obtained, where ΔR₄₆₀. is the difference in reflectance:

Granule 4 Granule 4a

Tea Stain 6.7 3.1

Blackcurrent stain 9.6 15.3 Blackberry stain 34.8 28.7 Curry stain 30.1 27.7

Wine stain 5.5 2.3

Chocolate ice-cream stain 35.4 31.4

The results show the granules were effective over a wide range of stains.

ii) Storage Stability

Storage experiments were carried out as described above. Granule 4 was found to have comparable storage stability to granules comprising a single hydrophobic binding agent.

iii) Residue Test

Into a 1 litre glass beaker maintained at a temperature of 40^βC was added 500ml tap water, ethoxylated nonionic surfactant with an average of 7E0 groups (0.5g), and of Mn granule (0.5g)

(particle size 500-710 μm). This was stirred for 2 minutes with a vortex of 4cm and subsequently filtered off over a sieve of 125 μm. The residue was collected and dried for 16 hours in an oven at 100^βC (the filter was placed on a petri dish). The weight of residues was then measured.

Granule % Residue 4 30

4a 66

Example 5

A granule with a mixed binding agent was also prepared by the following method.

Sodium stearate (77kg) was dissolved in molten lauric acid (77kg). Cetostearylstearate (66kg) was then blended into this mixture which was held at a temperature of approximately 75^βC. The molten mixture was dosed to a high shear mixer at a rate of 220 kg/hr where it was blended at a temperature of 60^βC with sodium bicarbonate (436 kg/hr), silica (294kg/hr) and manganese catalyst of formula III (30kg) to produce a fine powder.

This powder was then added to a low shear mixer where it was blended with titanium dioxide (20kg/hr) and subsequently cooled in a fluid bed. The resultant product was a granule with an average particle size around 500 microns.

Example 6

A granule according to the invention, having a mixed binding agent and including a combination of titanium dioxide and blue pigment to improve its white colour, was prepared as follows:

A premix of cetostearylstearate (92 parts by weight), lauric acid (92 parts by weight) and sodium stearate (46 parts by weight) was heated to about 80^βC to obtain a liquid. 100 parts by weight of the molten mix was then blended with 0.005 parts by weight of Colanyl-Blue B2G 100 (ex Hoechst).

Gasil 200TP silica (135 parts by weight), sodium bicarbonate (or alternatively sodium sulphate) (187 parts by weight) manganese catalyst of formula III (as in the previous Examples) (13.9 parts by weight) the above pigment-containing premix were granulated in a high shear mixer (Lodige recycler).

This powder was then added to a low/medium shear mixer (Lodige ploughshare) where it was blended with 23 parts by weight titanium dioxide. Final cooling in a fluid bed resulted in the final product having the following composition:

% bv weight

Gasil 200TP 29. .4 Sodium bicarbonate 40. .7 Cetostearylstearate 8. .7 Lauric acid 8. .7 Sodium stearate 4. .4 Mn catalyst 3. .0 Titanium dioxide 5. .0 Blue pigment 0. .001 Minors & moisture to 100%

The product obtained was a granular powder having an off-white colour.

Raw materials used:

Sodium Bicarbonate: Bicar Tec, Mittel Grade, ex- Solvay Silica: Gasil 200TP, ex-Crosfield Lauric Acid: Prifac 2920, ex-Unichema Sodium Stearate: E&R, Technical Grade Cetostearylstearate: Kemfluid 211, ex-Union Derivan Titanium Dioxide: Grade 1171, ex-Kronos Manganese Catalyst: Gandor, ex-Hickson & Welsh

Claims

1. A bleach catalyst composition in the form of non- friable composite granules characterised in that the granules comprise

i) a manganese complex catalyst selected from :-

(a) dinuclear manganese complexes of formula:-

wherein each Mn is manganese which may independently be in the III or IV oxidation state; each X independently represents a coordinating or bridging species selected from the group consisting of H₂0, 0₂ ²', 0²', OH", H0₂", SH", S²", >S0, Cl", N³\ SCN-, NH₂", NR, R^β ₃S0₄\ R'S0₃- and R"C00" where R^a is selected from H, alkyl, aryl, substituted alkyl and substituted aryl and R^bC00", where R^b is selected from alkyl, aryl, substituted alkyl and substituted aryl; z denotes the charge of the complex and is an integer which can be zero, positive or negative; Y is a monovalent or multivalent counter-ion, leading to charge neutrality, which is dependent upon the charge z of the complex; q = z/[charge Y] ; and

L is a ligand which is a macrocyclic organic compound of formula (I) :-

[NR³ - (CR^x(R²)_u)_t]_s (I)

C J

wherein t is an integer from 2 to 3; s is an integer from 3 to 4, u is 0 or 1; R¹, R² and R³ are each independently selected from H, alkyl, aryl, substituted alkyl and substituted aryl;

(b) dinuclear manganese complexes of formula:

wherein each Mn is manganese which may independently be in the III or IV oxidation state; each X independently represents a coordinating or bridging species selected from the group consisting of H₂0, 0₂ ²", 0²", OH-, H0₂-, SH", S²", >S0, Cl", N³-, SON^*, NH₂", NR, R^β ₃S0₄", R"S0₃" and R'COO" where R^a is selected from H, alkyl, aryl, substituted alkyl and substituted aryl and R^bC00", where R^b is selected from alkyl, aryl, substituted alkyl and substituted aryl; z denotes the charge of the complex and is an integer which can be zero, positive or negative; Y is a monovalent or multivalent counter-ion, leading to charge neutrality, which is dependent upon the charge z of the complex; q = z/[charge Y] ; and L is a ligand which comprises two species of formula (II) :- j— ^■[LNINRK⁴ -- (.Cv---R«^--Rκ²-)._u.),_t]j,,--,j (I)

wherein t is an integer from 2 to 3; s is an integer from 3 to 4, u is 0 or 1; R¹, R² and R⁴ are each independently selected from hydrogen, alkyl, aryl, substituted alkyl and substituted aryl, with the proviso that a bridging unit R⁵ is formed by one R⁴ unit from each ligand where R⁵ is the group (CR⁶R⁷)_n-(D)_p-(CR⁶R⁷)_B where p is 0 or 1; D is selected from a heteroatom such as oxygen and NR⁸ or is part of an aromatic or saturated homonuclear or heteronuclear ring, n is an integer from 1 to 4; m is an integer from 1 to 4; with the proviso that n + m ≤ 4; R⁶ and R⁷ are each independently selected from H, NR⁹ and OR¹⁰, alkyl, aryl, substituted alkyl and substituted aryl; and R⁸, R⁹, R¹⁰, are each independently selected from H, alkyl, aryl, substituted alkyl and substituted aryl;

(c) mononuclear manganese complexes of formula:-

[L Mn X_p]^zY_q

wherein Mn is manganese in the II, III or IV oxidation state; each X represents a coordinating species independently selected from OR¹¹, where R^u is a C₁-C₂₀ radical selected from the group consisting of alkyl, cycloalkyl, aryl, benzyl and radical combinations thereof or at least two R¹¹ radicals may be connected to one another so as to form a bridging unit between two oxygens that coordinate with the manganese, Cl", Br", I", F",

NCS-, N₃", I₃-, NH₃, OH", 0₂ ²-, HOO\ H₂0, SH, CN-

, OCN-, S₄ ²', R'COO", R*S0₃-, where R* is selected from H, alkyl, aryl, substituted alkyl and substituted aryl and R^bCOO where R^b is selected from alkyl or aryl, substituted alkyl and substituted aryl and mixtures thereof; p is an integer from 1 to 3; z denotes the charge of the complex and is an integer which can be zero, positive or negative;

Y is a monovalent or multivalent counter-ion, leading to charge neutrality, which is dependent upon the charge z of the complex; q ■ z/[charge Y]; and L is a macrocyclic organic compound of formula (I) as hereinbefore defined; ii) a hydrophobic binding agent; and iii) a non- eliquescent or non-hygroscopic soluble core material.

2. A bleach catalyst composition according to claim

1, wherein the hydrophobic binding agent is selected from silicone oils, C_u-C₁₈ fatty acids, C_n-C₁₈ fatty acid soaps, C_n-C₁₈ fatty esters, tri-, di- and monoglycerides, waxes, solid hydrocarbons and mixtures thereof.

3. A bleach catalyst composition according to claim

2, wherein the hydrophobic binding agent is a mixture of cetostearylstearate and a C_n-C₁₈ fatty acid or soap.

4. A bleach catalyst composition according to any one of claims 1 to 3, wherein the non-deliquescent or non- hygroscopic soluble core material is selected from sodium bicarbonate, manganese and potassium nitrates, magnesium sulphate and mixtures thereof.

5. A bleach catalyst composition according to any preceding claim, wherein the granules comprise from 0.5 to 20% by weight of the manganese complex catalyst, from 5 to 91 % by weight of the hydrophobic binding agent, and from 5 to 90% by weight of the non- deliquescent or non-hygroscopic soluble core material.

6. A bleach catalyst composition according to any preceding claim, wherein the granules further comprise an inert solid material selected from zeolites, silicas, clays, alumina, titanium dioxide and mixtures thereof.

7. A bleach catalyst composition according to any preceding claim, wherein the granules further comprise one or more pigment materials.

8. A bleach catalyst composition according to any preceding claim, wherein the granules have a pH in the range 4.5 to 8.5.

9. A bleach catalyst composition according to any preceding claim, wherein the particle size of the manganese complex catalyst is below 250μm.

10. A detergent and/or bleaching composition comprising: i) up to 50% by weight of one or more surfactant materials; ii) up to 50% by weight of one or more bleaching agents; iii) optionally from 5 to 80% by weight of one or more detergency builder materials; and iv) from 0.01 to 0.5% by weight of a bleach catalyst composition according to any one of claims 1 to 9.

11. A method of preparing a bleach catalyst composition in the form of non-friable composite granules, each individual granule comprising:

(i) from 0.5 to 20% by weight of a manganese complex catalyst; (ii) from 5 to 91% by weight of a hydrophobic binding agent; and (iϋ) from 5 to 90% by weight of a non-deliquescent or non-hygroscopic soluble core material;

the method comprising forming a mixture of (i), (ii) and (iii) and granulating the mixture using an apparatus selected from a pan granulator, fluidised bed, low energy mixers, compaction equipment, and a combined mixer/granulator.

12. A method of bleaching a stained substrate, comprising contacting the stained substrate in an aqueous medium with a detergent and/or bleaching composition according to claim 10.