WO2021097601A1

WO2021097601A1 - Solid bleach particles

Info

Publication number: WO2021097601A1
Application number: PCT/CN2019/119131
Authority: WO
Inventors: Manfred Mathes; Joerg Clemens; Stephane Streiff; Bing HONG; Joel Geny; Andrew WILLSON
Original assignee: Solvay Sa; Solvay (China) Co., Ltd
Priority date: 2019-11-18
Filing date: 2019-11-18
Publication date: 2021-05-27

Abstract

Solid bleach particles comprising: a) a compound of formula (I) wherein: -R is a hydrocarbyl radical, and each of the R groups may be the same or different -n is 1, 2 or 3 -m is 2, 3, 4 or 5; and b) solidparticles source ofhydrogen peroxide, wherein the compound of formula (I) is coated on the solid particles source of hydrogen peroxide.

Description

SOLID BLEACH PARTICLES

TECHNICAL FIELD

The invention relates to solid bleach particles, to a process for their manufacture and to their use in ADW (Automatic Dish Washing) or laundry detergent compositions.

BACKGROUND

Peroxide bleaching agents for use in laundering and dish washing have been known for many years. Such agents are effective in removing stains, such as tea, fruit and wine stains, from clothing or dishes at or near boiling temperatures. However, the efficacy of peroxide bleaching agents generally drops off sharply at temperatures below 60℃.

To achieve satisfactory bleaching action using sodium percarbonate (SPC,

an addition compound of sodium carbonate and hydrogen peroxide, like the one sold by Solvay under the tradename

) at temperatures below 60℃, so-called bleach activators are commonly used. These are mainly acylating agents incorporated in laundry products. When dissolved in washing liquor of pH 9–12, these activators preferentially react with hydrogen peroxide as released by SPC to form organic peracetic acid in situ. As a result of their higher oxidation potentials relative to hydrogen peroxide, these intermediates enable effective low-temperature bleaching. Due to their low concentration, resulting from the in-situ generation, these peroxyacids are much less aggressive to fabric dyes and fluorescent whitening agents in comparison with hydrogen peroxide or sodium hypochlorite. Widely used bleach activators are tetraacetylethylenediamine (TAED) or sodium p-nonanoyl-oxybenzenesulfonate (NOBS) . Both are expensive as well as adding to the bulk of the detergent since addition levels ofup to 5 to 10%by mass are common.

It is namely so that due to the different dissolution rates of both bleach ingredients SPC vs. TAED, aless optimal overall bleach performance in terms of generated peracetic acid is often obtained which is partly compensated by a required surplus of both SPC and TAED in detergent formulations in consideration of their optimal stoichiometric relation only.

As an alternative to bleach activators, numerous attempts have been made to introduce small amounts of catalysts that directly increase the low temperature bleaching action of sodium perborate or sodium percarbonate in the detergent base. Such catalysts are expensive and are typically aggressive towards the detergent base. This manifests itself as a reduced acceptable storage time of the formulations due to an accelerated loss of available oxygen content.

In most cases, these catalysts contain traces of heavy metal ions which are incorporated into the catalyst structure. Note that the addition of heavy metal ions, by themselves, can cause accelerated loss of AvOx. Furthermore, transition metals, when introduced independently have no positive effect on bleaching action when introduced independently, and even worse, seem to diminish the bleaching action was well as causing serious fiber and color damage. Despite these concerns, the patent literature describes a number of examples in which the bleaching power of sodium perborate or sodium percarbonate can be increased by heavy metal ion chelates; the effectiveness of such systems remains controversial and, generally speaking, these catalysts have not been accepted as a part of the washing process.

The excellent catalytic bleach enhancement by manganese complexes derived from 1, 4, 7-trimethyl-1, 4, 7-triazacyclononane ( “TMTACN” , also known as ‘dragon ligand’ or “Me3TACN” ) or related ligands are well known and described in literature. Such manganese complexes are also known as ‘Dragon catalyst’ in literature. However, under certain conditions severe dye and fiber damage has been observed in connection with such manganese catalyst system. Besides, this catalytic system is so reactive that it can trigger decomposition of other ingredients present in the formulation inducing powder yellowing. Not only the aesthetic is impacted but performance over time is decreasing.

The Applicant has recently discovered that use of the ligand alone, in the formulation will not have any negative impact on the detergent stability as the catalyst is not yet formed by complexation with metal (s) . Besides, the class of amine compounds to which it belongs fulfils the demands of stability, both during the washing process and in the dispenser of the washing machine, and which are extremely active for catalyzing the bleaching action of a source of hydrogen peroxide on a wide variety of stains, notably at low to medium temperatures of 10-40℃. Hence, WO 2018/141237 in the name of Solvay (and the content of which is incorporated by reference in the present application) concerns a composition, notably a bleach or detergent composition, comprising at least:

a) a compound of formula (I)

wherein:

- R is a hydrocarbyl radical, and each of the R groups may be the same or different

- n is 1, 2 or 3

- m is 2, 3, 4 or 5; and

b) a source of hydrogen peroxide.

It namely appeared that the combination/mixture of these compounds a) and b) permits to obtain very good bleaching properties while lowering the amount of compounds of formula (I) in comparison with other amines used on the market. Furthermore, this combination permits to obtain very good bleaching properties without damaging the fabrics in comparison with the dinuclear manganese complex catalysts. It also appears that this combination permits to obtain significant bleaching properties without the use of detergent.

A drawback of the disclosure of WO 2018/141237 lies however in the fact that components a) and b) have to be mixed in the “detergent” composition by the soapers (detergent makers) , which adds an ingredient to their recipe (namely component a) ) which is by the way present in a very low amount, which makes it difficult to achieve a homogeneous mixture.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 shows bleaching results obtained on tea stained fabrics with different liquid washing media some of them including solid bleach particles according to the invention and others not.

Figure 2 shows bleaching results obtained on coffee stained fabrics with different liquid washing media some of them including solid bleach particles according to the invention and others not.

THE INVENTION

The Applicant has now discovered that quite surprisingly, these amine compounds of formula I and in particular, the above mentioned TMTACN or dragon ligand, can be applied as a coating to a solid peroxide particle, in particular a SPC particle, without impinging its stability. This combination of the ligand with the peroxide source in a single granule will make the detergent production process easier (2 in 1) and cheaper by adding only one active ingredient instead of two.

Therefore, the present invention concerns solid bleach particles comprising:

a) a compound of formula (I)

wherein:

- n is 1, 2 or 3

- m is 2, 3, 4 or 5; and

b) solid particles source of hydrogen peroxide (SPSHP) ,

wherein the compound of formula (I) is coated on the solid particles source of hydrogen peroxide.

The invention concerns also a process for making such solid bleach particles and a detergent composition comprising such solid bleach particles.

The present invention also concerns specific uses of such solid bleach particles.

DETAILS OF THE INVENTION

In the context of the present invention, bleaching should be understood as relating generally to the discoloration of stains or of other materials attached to or associated with a substrate. However, it is envisaged that the present invention can be applied where a requirement is the removal and/or neutralization by an oxidative bleaching reaction of malodors or other undesirable components attached to or otherwise associated with a substrate. Furthermore, in the context of the present invention bleaching is to be understood as being preferably restricted to any bleaching mechanism or process that does not require the presence of light or activation by light.

In the context of the present invention, by “coated” it means in fact that the compound of formula (I) is incorporated in a coating layer i.e. a layer of a solid coating composition comprising the compound of formula (I) and optionally a carrier which may be an organic or an inorganic compound (or a mixture of both organic and inorganic compounds) that will be detailed later on; and eventually other ingredients.

Generally speaking, a “coating” is a covering that is applied to the surface of an object, usually referred to as the substrate. In the frame of the invention, it means hence a covering layer that may be applied to the solid particles source of hydrogen peroxide (SPSHP) as they are, or that may be applied to such particles alreadybearing a coating.

Compound offormula (I)

In the compound of formula (I) , R may be a C ₁-C ₃₀-hydrocarbyl radical, preferably a C ₁-C ₁₅-hydrocarbyl radical.

R may notably be C ₁- ₃₀-alkyl radicals, preferably C ₁- ₂₀-alkyl radicals, particularly preferably C ₁- ₁₀-alkyl radicals, which can be straight-chain or branched and may carry one or more substituents. R may be C ₂- ₃₀-alkenyl radicals, preferably C ₂- ₂₀-alkenyl radicals, particularly preferably C ₂- ₁₀-alkenyl radicals, which can be straight-chain or branched and may carry one or more substituents and/or one or more functions. R may also be C ₅- ₁₈-cycloalkyl radicals which may have branches. R may furthermore be C _7-18-aralkyl radicals in which an aromatic radical is bonded via an alkyl group to the amine nitrogen atom. R may also be C ₇- ₁₈-heteroalkyl radicals or C ₆- ₁₈-aryl radicals or C ₃- ₁₈-heteroaryl radicals, with, in the last-mentioned compounds, an aromatic radical being directly linked to the amine nitrogen atom.

R may furthermore carry one or more, preferably zero or one, substituents such as hydroxyl groups, C ₁- ₄-alkoxy radicals, amino groups, C ₁- ₄-alkylamino radicals, (di-C _1-4-alkyl) amino radicals, chlorine atoms, bromine atoms, nitro groups, cyano groups, C ₁- ₄-alkylthio radicals, C ₁- ₄-alkylsulfonyl radicals, carbonyl radicals, carboxyl groups, sulfo groups, sulfate groups, carboxy-C ₁- ₄-alkyl radicals, carbamoyl radicals or phenyl, tolyl or benzyl radicals.

The carbon chains of R may furthermore be interrupted by oxygen atoms, imino groups, C ₁- ₄-alkylimino radicals, iminocarbonyl radicals, oxycarbonyl radicals or carbonyl radicals.

R is preferably a C ₁- ₅-hydrocarbyl radical, preferably a methyl radical.

Compounds of formula (I) may be chosen in the group constituted by triazacycloalkanes and tetraazacycloalkanes.

Compounds of formula (I) may be chosen in the group constituted by: 1, 3, 5-trimethyl-1, 3, 5-triazacyclohexane; 1, 3, 5-trimethyl-1, 3, 5-triazepane; 1, 3, 5-trimethyl-1, 3, 5-triazocane; 1, 3, 5, 7-tetramethyl-1, 3, 5-triazocane; 1, 3, 6-trimethyl-1, 3, 6-triazocane; 1, 3, 5-trimethyl-1, 3, 5-triazonane; 1, 3, 6-trimethyl-1, 3, 6-triazonane; 1, 3, 6, 8-tetramethyl-1, 3, 6-triazonane; 1, 4, 7-trimethyl-1, 4, 7-triazacyclononane; 1, 3, 5-trimethyl-1, 3, 5-triazecane; 1, 3, 6-trimethyl-1, 3, 6-triazecane; 1, 3, 7-trimethyl-1, 3, 7-triazecane; 1, 3, 5, 7-tetramethyl-1, 3, 7-triazecane; 1, 3, 5, 7, 9-pentamethyl-1, 3, 7-triazecane; 1, 3, 5, 7-tetramethyl-1, 3, 5-triazecane; 1, 4, 7-trimethyl-1, 4, 7-triazecane; 1, 4, 7, 9-tetramethyl-1, 4, 7-triazecane; 1, 4, 7-trimethyl-1, 4, 7-triazacycloundecane; 1, 4, 8-trimethyl-1, 4, 8-triazacycloundecane; 1, 4, 6, 8-tetramethyl-1, 4, 8-triazacycloundecane; 1, 4, 7-trimethyl-1, 4, 7-triazacyclododecane; 1, 4, 7, 10-tetramethyl-1, 4, 7, 10-tetraazacyclododecane; 1, 4, 7, 10-tetramethyl-1, 4, 7-triazacyclododecane; 1, 4, 8-trimethyl-1, 4, 8-triazacyclododecane; 1, 5, 9-trimethyl-1, 5, 9-triazacyclododecan; 1, 3, 5, 9-tetramethyl-1, 5, 9-triazacyclododecane; and 2-methyl-1, 4, 7-trimethyl-1, 4, 7- triazacyclononane. Good results are obtained with 1, 4, 7-trimethyl-1, 4, 7-triazacyclononane (TMTACN or dragon ligand) .

The compound of formula (I) may be present in the solid bleach particles in an amount of 0.01-2%by weight, preferably of 0.1-1%and more preferably of 0.34-0.8%by weight of the total bleach particles.

The compound of formula (I) may be coated on the solid particles source of hydrogen peroxide as it is (generally starting from an aqueous solution thereof, of which water is evaporated by spray drying or incorporated into a coating composition which may be organic or inorganic (or be a mixture of both organic and inorganic substances) but which must be water soluble at usual bleaching/washing temperatures, preferably at or below 60℃, notably at low to medium temperatures of 10-40℃.

Hence, in one embodiment, the compound of formula (I) is embedded in a composition comprising a water soluble organic or inorganic carrier. The coating composition may comprise other ingredients like stabilizers like chelating agents (HEDP or HydroxyEthylidene DiPhosphonic Acid for instance) , enzymes, optical or fluorescent brightening agents, bleach activators (like TAED) , perfume, soil release polymers (like acrylates, PET etc. ) and the like.

As organic carriers, mention can be made of water soluble polymers like polyethylene glycol (PEG) or polypropylene glycol (PPG) with an appropriate molecular weight to be water soluble and eventually melt at a low temperature between 20-90℃; preferably between 30-80℃; more preferably between 40-70℃ if they are applied by melt coating instead of spray coating. Good results are obtained with PEG. Typically, their molecular weight MW is from about 1000 to 100000, preferably from 5000 to 50000, values of from 8000 to 35000 giving good results in the case of PEG more particularly. The coating composition may comprise other ingredients like stabilizers etc.

As to suitable inorganic carriers, mention can me made of water soluble inorganic salts like for instance soda ash, sodium sulphate, sodium silicate or mixtures thereof. A mixture of soda ash and sodium sulphate (also called SCM) gives good results, especially if both are used in a respective weight ratio of 30: 70 gives good results in practice.

The use of an organic carrier can lead to the coated particles to lump. Hence, in case such a carrier is used for the compound of Formula (I) , an additional coating layer comprising an inorganic carrier (for instance like the one described above) may be required on top, for instance in an amount of 5wt%or higher.

Solid particles source of hydrogen peroxide

Solid particles source of hydrogen peroxide (SPSHP) are well known in the art and they are usually referred to as hydrogen peroxide-liberating or-generating compounds.

The SPSHP of the present invention are preferably chosen in the group constituted by: alkali or alkaline earth metal peroxides particles; organic peroxides particles, such as urea peroxide or ε-phthalimido peroxy hexanoic acid (PAP) particles; inorganic persalts particles, such as the alkali metal perborates, percarbonates, perphosphates, or persulphates particles. Mixtures of two or more such SPSHP may also be suitable.

Sodium perborate monohydrate is preferred to tetrahydrate because of its excellent storage stability while also dissolving very quickly in aqueous bleaching solutions. Sodium percarbonate (SPC like the above mentioned

grades from Solvay) and ε-phthalimido peroxy hexanoic acid (PAP like the

grades from Solvay) particles may be preferred namely for environmental reasons.

As to the particle size of the solid bleach particles of the invention, it is preferably of 100-2000μm, more preferably 200-1000μm and most preferably 400-900μm.

The solid bleach particles of the present invention preferably contain at least 65wt%of the SPSHP, more preferably at least 85wt%and even more preferably, at least 90wt%of the SPSHP. Generally, the only other constituents of the solid bleach particles of the invention are those of the coating layer (s) .

One aspect of the invention is that the transition metal ions normally used in combination with compounds of formula (I) to generate active catalysts but which are known for their risk of damaging clothing, can be reduced or even absent from the detergent compositions using the bleach particles of the invention because such metals generally are available in situ and in sufficient amount during the washing because contained in the dirt/stain, in the detergent powder and/or in the washing device as common impurities.

However, in order not to be too depended on the actual availability/amount of such transition metals by e.g. dishes or dirty laundry, sufficient amounts of transition metals can be incorporated into the bleach particles of the invention to ensure sufficient amounts of catalyst in situ for optimal bleach performances. This embodiment of the invention affords therefore several advantages: the need for TAED is removed thus simplifying the production process and reducing the volume of the detergent, as well as providing bleaching action at lower temperatures thereby reducing thermal stress to clothing.

Hence, in a preferred embodiment, the bleach particles of the invention also contain transition metal ions which are preferably also coated on the SPSHP. Suitable transition metals are divalent ones like Fe2+and/or Mn2+. Especially Mn2+gives good results, but Fe2+also works and is less aggressive towards textiles. In order to prevent the catalytic decomposition of the hydrogen peroxide source, these transition metal ions are preferably applied to SPSHP already bearing a coating, preferably a coating of a water soluble inorganic salt as described above.

For the same reason, the transition metal ions are preferably encapsulated in a protective layer (for instance of a polymer) which does not melt during the coating of said transition metal ions on the SPSHP. Alternatively, the transition metal ions may be embedded in an inert inorganic carrier like waterglass.

The amount of transition metal ions in the bleach particles is generally in the range of from 0 to 1000 ppm (of the total weight of said bleach particles) , preferably of from 50 to 200 ppm. It is namely so that some stains contain transition metal ions so that they do not require any addition of the same. Also, transition metal sources usually are available in surplus by e.g. detergent powder or washing device.

Manufacturing process

Several approaches are possible in order to coat the compound of formula (I) and/or transition metal ions, the case being, onto the solid particles source of hydrogen peroxide (SPSHP) . Same approaches are by the way available for also applying other coating layers on the SPSHP within the scope of the invention.

Generally speaking, coating can be done by spray coating a solution of a coating composition (in water or another solvent, preferably water) or by melt coating a coating composition on the SPSHP.

Hence, the present invention also concerns a process for manufacturing solid bleach particles as described above wherein a coating composition comprising a compound of formula (I) is applied on the SPSHP by spray coating or by melt coating.

This coating composition may also comprise transition metal ions, preferably pre-encapsulated as described above, or an additional coating layer may be applied to the SPSHP which comprises transition metal ions preferably pre-encapsulated as described above.

These transition metal ions are preferably introduced as salts like for instance salts of Fe or Mn, like Fe or Mn sulphate, more particularly FeSO4*7H2O or MnSO4*H2O, or mixtures thereof.

The above mentioned coating layers (comprising a compound of formula (I) and/or transition metal ions) may be applied to the SPSHP as they are, or they may be applied to SPSHP already bearing a coating free of compounds of formula (I) and of transition metal ions, for instance based on a water soluble inorganic salt as described above. Also, it may be preferable to apply such a coating layer (free of compounds of formula (I) and of transition metal ions) on top of a coating layer comprising transition metal ions in case such ions are not encapsulated in a protective layer or embedded in an inert inorganic carrier like waterglass.

In a first embodiment, the process of the invention comprises the introduction of compound of formula (I) into a molten polymer like PEG, which cools down to a dense organic mass; after grounding of the latter to fine particles, it is coated onto the SPSHP by a melt coating process or if dissolved in an aqueous solution, coated by a spray coating process onto it. In case a transition metal ion is added as booster, it may be incorporated (preferably pre-encapsulated as described above) into this same coating layer, or be incorporated in a subsequent coating layer obtained the same way.

In a second embodiment, the process of the invention comprises dissolving the compound of formula (I) in water or a suitable inorganic coating solution (for instance a saturated coating solution of soda ash and sodium sulphate in a ratio of 30: 70) and then spray coating this solution onto the SPSHP. Such coated multifunctional granules can be subsequently coated with an organic carrier of transition metals as booster, e.g. PEG, PPG or comparable comprising a transition metal salt, preferablypre-encapsulated.

In the process of the invention, the outer (top) coating layer preferably is a coating layer comprising an inorganic carrier (preferably a water soluble inorganic salt) to overcome possible lumping phenomena during transport or storage of such granules in bulk.

Bleaching Compositions

The present invention also concerns bleaching compositions comprising bleach particles as described above.

The compositions of the invention may further comprise a detergent. Detergents are usually defined as a surfactant or a mixture of surfactants having cleaning properties in dilute solutions.

The detergent compositions of the invention will normally also contain a detergency builder.

Apart from the components already mentioned, the bleaching compositions of the invention can contain any of the conventional additives in the amounts in which such materials are normally employed in fabric or dish washing detergent compositions.

The bleaching compositions of the invention may further comprise water. In this case, the pH of the compositions may be from 7 to 12, preferably from 9 to 11.

Bleaching compositions of the invention formulated as free-flowing particles, e.g. in powdered or granulated form, can be produced by any of the conventional techniques employed in the manufacture of detergent compositions, for instance by slurry-making, followed by spray-drying to form a detergent base powder to which the heat-sensitive ingredients can be added as dry substances.

It will be appreciated, however, that the compositions can itself be made in a variety of other ways, such as the so-called part-part processing, non-tower route processing, dry-mixing, agglomeration, granulation, extrusion, compacting and densifying processes etc., such ways being well known to those skilled in the art.

Applications/uses

The present invention also concerns the use of the solid bleach particles described above for treating a substrate, notably for bleaching a substrate, more particularly laundry or dishes.

Any suitable substrate that is susceptible to bleaching or one that one might wish to subject to bleaching may be used, such as a textile for instance. Preferably the textile is a laundry fabric or garment.

In a preferred embodiment, the method is carried out on a laundry fabric using an aqueous treatment liquor. In particular, the treatment may be effected in a wash cycle for cleaning laundry. More preferably, the treatment is carried out in an aqueous detergent bleach wash liquid.

The invention also concerns a method for washing tableware in a domestic automatic dishwashing appliance, comprising treating the soiled tableware in an automatic dishwasher with the solid bleach particles described above. The present invention also relates to automatic dishwashing rinse aid compositions and methods for treating tableware in a domestic automatic dishwashing appliance during a rinse cycle.

The solid bleach particles described above may also be applied in the peroxide oxidation of a broad range of organic molecules such as olefins, alcohols, aromatic ethers, sulphoxides and various dyes, and also for inhibiting dye transfer in the laundering of fabrics. Hence, the present invention also concerns the use of solid bleach particles as described for the oxidation of organic molecules.

EXPERIMENTAL PART

Coating procedures

Melt coating

Preheating of a LOEDIGE mixing system apparatus up to 75℃ max; charging it with 1-2kg SPC and with coating particles including TMTACN or transition metals (the latter can be added in solid or liquid phase) ; 30–45 minutes mixing at 75℃; cooling at a temperature below 30℃ and discharge

Spray coating

Charging of a GLATT fluidized bed spray coating apparatus with 1-2kg SPC; preheating of load up to 60℃ max (below melting point of PEG) ; spraying time of aq. SCM, aq. ligand or aq. PEG solution: 30–60 minutes depending on coating level at 45-48℃; final drying to 50–57℃ max; cooling at a temperature below 30℃ by air and discharge.

Example 1: chemical compatibility of SPC with PEG

Several polyethylene glycol grades (PEG8000 to PEG35000 i.e. having a molecular weight of 8000 to 35000) were tested to assess their chemical compatibility with pure sodium percarbonate (SPC) , if coated by a melting (LOEDIGE mixer) or spray coating process (GLATT fluidized bed process dryer) . Latter compatibility is assessed in terms of monitored thermal activity of coated particles at 55℃ by TAM machines (highly sensitive heat flux calorimeter from TA Instruments) . Independent of the coating process or tested PEG grades, thermal activities at 55℃ of coated SPC with PEG remain below 18μW/g, which indicate a quite good compatibility of both chemical compounds at all due to the fact that thermal activities below 18μW/g already equals common activities and therefore thermal stability of pure SPC at 55℃. Hence PEG(or PPG or comparable) are a suitable carrier for catalyst ligands and/or transition metals to boost generation of bleach catalysts in situ.

Example 2: chemical compatibility of SPC with PEG and TMTACN ligand

Liquid 1, 4, 7-trimethyl-1, 4, 7-triazacyclononane (TMTACN) as catalyst ligand was added to liquefied PEG at 80°-90℃. After cooling down to a dense organic PEG/ligand mixture, said mixture was crushed and milled to fine PEG/ligand particles. Such particles were coated onto SPC by both coating processes (melting/spraying) . Monitored thermal activities at 55℃ of less than 18μW/g confirmed the remarkable thermal stability of coated granules, which contain finally about 0.33%m/m (i.e. wt%of the total weight of particles) of the ligand in 5%PEG m/m as organic coating layer.

Example 3: SPC coated with PEG and TMTACN ligand, and with an inorganic top coat

A coating level of 5%m/m and higher of SCM (soda ash/sodium sulfate 30: 70 weig ht ratio) was applied on top of samples of Example 2 not for stability reasons but for supply chain reasons (to suppress the tendency of coated particles to lump if stored or transported in bulk (e.g. flexible IBCs, silo trucks or tanks) ) . The high thermal stability of such samples was confirmed (thermal activities at 55℃ of less than 18μW/g) .

Example 4: chemical compatibility of SPC with TMTACN ligand

TMTACN was dissolved in tap water or saturated coating solutions of SCM. It was shown that TMTACN in aqueous solution can be coated directly onto SPC at a level of 0.33%m/m or higher or via any inorganic coating solution at 5%to 10%coating level in total by for instance fluidized bed processes or others. Latter process capability and compatibility with SPC is confirmed by corresponding monitored thermal activities at 55℃ at a range of<18μW/g up to <30μW/g depending on the coating sequence or kind of sprayed coating solution as carrier of the ligand. No lumping phenomena were observed in this case.

Example 5: chemical compatibility of SPC with PEG and transition metals

Transition metal ions (namely incorporated as FeSO4*7H2O and MnSO4*H2O) were added to liquefied PEG 35000 (5%m/m) or an inorganic coating solution (10%m/m SCM) at a concentration of 100ppm in respect to the final coated particles. Most of the coating trials indicated an increased thermal activity at 55℃ at about 100μW/g or higher, which is not caused by any intermediate generation of catalyst inside granules during coating performance, but allegedly owed to the intrinsic property of the transition metals to trigger the catalytic decomposition of hydrogen of SPC. Applying a base coat of 15%SCM and a top coat of 5%SCM reduced this emission level at 57μW/g. Applying a base coat of 25%SCM and a top coat of 5%SCM even reduced this emission level at 19 μW/g.

Example 6: chemical compatibility of SPC with PEG and encapsulated transition metals

Iron sulphate was put solid in molten PEG35000 (1%m/m) at a concentration of 100ppm in respect to the final coated particles. Such encapsulated transition metal ions were then incorporated in molten PEG8000 (4%m/m and 9%m/m) and then coated onto SPC bearing an SCM coating at a level of 10wt%in respect to the final coated particles. The thermal activity measured was at about 50μW/g.

Example 7: chemical compatibility of SPC with water glass and transition metals

Transition metal ions (namely FeSO4*7H2O) were added to water glass (2.5%m/m) at a concentration of 100ppm in respect to the final coated particles and then spray coated onto SPC bearing an SCM coating at a level of 10wt%in respect to the final coated particles. The thermal activity measured was 8μW/g.

Example 8: bleach performance tests

Stained fabrics were bleached with different liquid media as described in Table 1 (for tea stain) and Table 2 (for coffee stain) attached.

The bleaching procedure used was a follows:

Into a beaker with 1L hard water containing 200 mg of CaCO3 and fitted with a pH and conductivity electrode, 2.0g of a standard detergent GB/T13174-2014 (E2P2L) having the following composition:

(the case being) was added and the mixture was stirred at 200rpm for 1 min. at a constant temperature of 40℃. The other additive (s) , the case being, were then added and dissolved for further two minutes. Finally, three stained fabric sheets of 5cm x 5cm each were added and bleached during 30 mins. After the bleaching, the bleached fabric pieces were washed with tap water three times at ambient temperature, squeezed and dried naturally inside an oven at 30℃ for at least two hours.

The bleaching performance was evaluated using a commercial spectrophotometer DATACOLOR 200M.

The color difference (ΔE) before and after bleaching is the length of the vector in the CIELAB color space calculated with the following formula:

The values obtained are listed in Tables 1 and 2 as well.

Besides, a visualization of the associated bleach performance for some of these tests is pictured in Figures 1 and 2 attached.

From these results, it can be concluded that on tea and coffee stain:

- the ligand coated on PCS performs as well as a mixture of the ligand with the other ingredients of the washing formulation and almost as well as the dragon catalyst; encapsulated in TAED at 2%by weight effective;

- 3 mg/l of the ligand coated on PCS performs as well as 200 mg/l of TAED; and

- increasing the amount of coated ligand from 3 to 6 mg/l does not bring an improvement in stain removal; however, the trials were repeated after several weeks ofstorage and then, it appeared that more than 4 mg/l of the coated ligand are required to have a stable activity during at least 8 weeks.

Claims

Solid bleach particles comprising:

a) a compound of formula (I)

wherein:

- R is a hydrocarbyl radical, and each of the R groups may be the same or different

- n is 1, 2 or 3

- m is 2, 3, 4 or 5; and

b) solid particles source of hydrogen peroxide (SPSHP) ,

wherein the compound of formula (I) is coated on the solid particles source ofhydrogen peroxide.
Solid bleach particles according to the preceding claim, wherein the compound of formula (I) is chosen in the group constituted by triazacycloalkanes and tetraazacycloalkanes.
Solid bleach particles according to the preceding claim, wherein the compound of formula (I) is 1, 4, 7-trimethyl-1, 4, 7-triazacyclononane (TMTACN or dragon ligand) .
Solid bleach particles according to any of the preceding claims, wherein the compound of formula (I) is embedded in a coating composition comprising a water soluble organic or inorganic carrier.
Solid bleach particles according to the preceding claim, wherein the carrier is an organic carrier selected from water soluble polymers like polyethylene glycol (PEG) or polypropylene glycol (PPG) with an appropriate molecular weight.
Solid bleach particles according to claim 4, wherein the carrier is a water soluble inorganic salt selected from soda ash, sodium sulphate, sodium silicate, and mixtures thereof.
Solid bleach particles according to the preceding claim, wherein the carrier is a mixture of soda ash and sodium sulphate preferably in a respective weight ratio of 70: 30.
Solid bleach particles according to claim 4, wherein the carrier is an organic carrier and wherein an additional coating layer comprising an inorganic carrier is present on top of the coating layer comprising the compound of formula (I) and the organic carrier.
Solid bleach particles according to any of the preceding claims, wherein the SPSHP is selected from the group constituted by: alkali or alkaline earth metal peroxides particles; organic peroxides particles, such as urea peroxide or ε-phthalimido peroxy hexanoic acid (PAP) particles; inorganic persalts particles, such as the alkali metal perborates, percarbonates, perphosphates, or persulphates particles; or mixtures thereof.
Solid bleach particles according to the preceding claim, wherein the SPSHP is sodium percarbonate or ε-phthalimido peroxy hexanoic acid (PAP) .
Solid bleach particles according to any of the preceding claims, said solid bleach particles containing at least 65wt%of the SPSHP.
Solid bleach particles according to any of the preceding claims, said solid bleach particles containing transition metal ions like Fe2+and/or Mn2+which are also coated on the SPSHP.
Solid bleach particles according to the preceding claim, wherein the transition metal ions are applied to SPSHP already bearing a coating, preferably a coating of a water soluble inorganic salt
Solid bleach particles according to claim 12 or 13, wherein the transition metal ions are either encapsulated in a protective layer (for instance of a polymer) which does not melt during the coating of said transition metal ions on the SPSHP, or embedded in an inert inorganic carrier like waterglass.
Process for manufacturing solid bleach particles according to any of the preceding claims, wherein a coating composition comprising a compound of formula (I) is applied on the SPSHP by spray coating or by melt coating.
Process according to the preceding claim, wherein the coating composition also comprises transition metal ions or wherein an additional coating layer is applied to the SPSHP which comprises transition metal ions.
Process according to the preceding claim, wherein the coating layer (s) is/are applied to SPSHP already bearing a coating free of compounds of formula (I) and of transition metal ions.
Process according to claim 16 or 17, wherein a coating layer free of compounds of formula (I) and of transition metal ions is applied on top of the coating layer comprising transition metal ions.
Process according to any of claims 15 to 18, wherein a coating layer comprising an inorganic carrier (preferably a water soluble inorganic salt) is applied as outer coating layer.
Bleaching composition comprising solid bleach particles according to any of claims 1 to 14, or obtained by a process according to any of claims 15 to 19.
Use of the solid bleach particles according to any of claims 1 to 14, or obtained by a process according to any of claims 15 to 19, for treating a substrate, notably for bleaching a substrate, more particularly laundry or dishes.
Use of the solid bleach particles according to any of claims 1 to 14, or obtained by a process according to a process according to any of claims 15 to 19, for the oxidation of organic molecules.