AU636629B2 - Liquid bleach composition - Google Patents

Description

LIQUID BLEACH COMPOSITION

The present invention relates to a liquid detergent composition comprising an aqueous base, detergent active materials and a bleach material.

It has been proposed in EP 293 040 (P&G) to formulate liquid detergent compositions which comprise a perborate bleach material and a water-soluble solvent system to increase the stability of the bleach in the aqueous phase. Similar solvents in combination with bleaches are proposed in EP 294 904 (P&G), this document also discloses the in-situ preparation of perborate by reacting metaborate with hydrogen peroxide.

In formulating liquid aqueous detergent compositions comprising a bleach material, we have noted that bleach instability problems sometimes occur. Although not yet fully understood this instability is believed to be caused by the solubilisation of the bleach materials in the aqueous phase, followed by the decomposition of the dissolved bleach materials.

Surprisingly it has now been found that stable bleach containing liquid aqueous detergent compositions can be formulated, provided that said compositions also

comprise a specific boron electrolyte, obtainable by using metaborate.

Accordingly, the present invention relates a liquid detergent composition comprising an aqueous base, a bleach material and from 2-60 % by weight of detergent active materials, wherein the composition also comprises a metaborate electrolyte or a boron electrolyte

obtainable by using a metaborate electrolyte. bleach material

Compositions according to the present invention

comprise a bleach material, which is preferably a peroxygen bleach. This bleach component may be present in the system in dissolved form, but preferred is that only part of the peroxygen bleach is solubilized, the remaining part preferably being present as solid

peroxygen particles which are suspended in the system.

Examples of suitable bleach compounds include hydrogen peroxide, the perborates, persulfates, peroxy

disulfates, perphosphates and the crystalline

peroxyhydrates formed by reacting hydrogen peroxide with urea or alkali metal carbonate. Also encapsulated bleaches may be used. Preferred bleaches are only partially soluble in the system. Especially preferred is the use of perborate or percarbonate bleaches. The bleach component is preferably added in an amount corresponding to 0.1 to 15% by weight of active oxygen, more preferred from 0.5 to 10% active oxygen, typically from 1.0 to 5.0% active oxygen. Typical amounts of bleach will be between 1 and 40 % by weight of the aqueous composition, more preferred from 7 to 30%, especially preferred from 10 to 25 % by weight of the composition. metaborate electrolyte

Compositions of the invention also comprise a metaborate electrolyte or a boron electrolyte obtainable by using metaborate. Suitable metaboric compounds include for example netaboric acid, alkali metal metaborates and alkali earth metal metaborates.

Surprisingly it has been found that from the class of boron compounds especially the use of metaborate and its derivatives is preferred because of their excellent ability to stabilize bleach systems. Although not yet fully understood it is believed that the metaborate electrolyte can have two functions, firstly it prevents the solubilisation of the bleach material, therewith minimizing the amount of instable dissolved bleach and secondly it retards the decomposition of the dissolved bleach materials. The level of metaborate electrolyte is preferably more than 0.1 % by weight of the compositions, especially preferred more than 0.2 % by weight of the composition, most preferred more than 0.4 %. Generally the level of metaborate electrolyte is less than 10%, more preferred less than 7 %, especially preferred less than 5 %.

Typical levels of metaborate electrolytes are from 0.5 to 5 %.

The percentages for the metaborate electrolyte are calculated on the basis of the anhydrous metaborate equivalent of the electrolyte. For the purpose of the present invention the metaborate level is preferably determined by measuring the boron content of the formulation and subsequently calculating the

corresponding level of metaborate at a standard pH of 11. Preferably the calculated level of the metaborate at the standard pH is then defined as the metaborate level in the composition. Preferably the molar ratio of metaborate or boron equivalent thereof to hydrogen peroxide (if any) in the ready to use composition is more than 1 : 1, preferably more than 2 : 1, most preferred more than 5 : 1. detergent active materials

Compositions of the present invention also comprise detergent active materials. Surprisingly it has been found that a combination of bleach materials and

metaborate electrolytes or boron derivatives thereof is suitable for use in ready to use aqueous liquid

detergent compositions.

In the widest definition the detergent active materials in general, may comprise one or more surfactants, and may be selected from anionic, cationic, nonionic, zwitterionic and amphoteric species, and {provided mutually compatible) mixtures thereof. For example, they may be chosen from any of the classes, sub-classes and specific materials described in "Surface Active Agents" Vol. I, by Schwartz & Perry, Interscience 1949 and

"Surface Active Agents" Vol. II by Schwartz, Perry & Berch (Interscience 1958), in the current edition of

"McCutcheon's Emulsifiers & Detergents" published by the McCutcheon division of Manufacturing Confectioners

Company or in Tensid-Taschenburch", H. Stache, 2nd Edn., Carl Hanser Verlag, Munchen & Wien, 1981.

Suitable nonionic surfactants include, in particular, the reaction products of compounds having a hydrophobic group and a reactive hydrogen atom, for example

aliphatic alcohols, acids, amides or alkyl phenols with alkylene oxides, especially ethylene oxide either alone or with propylene oxide. Specific nonionic detergent compounds are alkyl (C₆-C₁₈) primary or secondary linear or branched alcohols with ethylene oxide, and products made by condensation of ethylene oxide with the reaction products of propylene oxide and

ethylenediamine. Other so-called nonionic detergent compounds include long chain tertiary amine oxides, long chain tertiary phospine oxides and dialkyl sulphoxides. Also possible is the use of salting out resistant active materials, such as for example described in EP 328 177, especially the use of alkyl poly glycoside surfactants, such as for example disclosed in EP 70 074. Suitable anionic surfactants are usually water-soluble alkali metal salts of organic sulphates and sulphonates having alkyl radicals containing from about 8 to about 22 carbon atoms, the term alkyl being used to include the alkyl portion of higher acyl radicals. Examples of suitable synthetic anionic detergent compounds are sodium and potassium alkyl sulphates, especially those obtained by sulphating higher (C₈-C₁₈) alcohols produced for example from tallow or coconut oil, sodium and potassium alkyl (C₉-C₂₀) benzene sulphonates,

particularly sodium linear secondary alkyl (C₁₀-C₁₅) benzene sulphonates; sodium alkyl glyceryl ether

sulphates, especially those ethers of the higher

alcohols derived from tallow or coconut oil and

synthetic alcohols derived from petroleum; sodium coconut oil fatty monoglyceride sulphates and

sulphonates; sodium and potassium salts of sulphuric acid esters of higher (C₈-C₁₈) fatty alcohol-alkylene oxide, particularly ethylene oxide, reaction products; the reaction products of fatty acids such as coconut fatty acids esterified with isethionic acid and

neutralised with sodium hydroxide; sodium and potassium salts of fatty acid amides of methyl taurine; alkane monosulphonates such as those derived by reacting alpha- olefins (C₈-C₂₀) with sodium bisulphite and those derived from reacting paraffins with SO₂ and Cl₂ and then hydrolysing with a base to produce a random

sulponate; and olefin sulphonates, which term is used to describe the material made by reacting olefins,

particularly C₁₀-C₂₀ alpha-olefins, with SO₃ and then neutralising and hydrolysing the reaction product. The preferred anionic detergent compounds are sodium (C₁₁- C₁₅) alkyl benzene sulphonates and sodium or potassium primary (C₁₀-C₁₈) alkyl sulphates.

It is also possible, and sometimes preferred, to include an alkali metal soap of a fatty acid, especially a soap of an acid having from 12 to 18 carbon atoms, for example oleic acid, ricinoleic acid, and fatty acids derived from castor oil, alkylsuccinic acid, rapeseed oil, groundnut oil, coconut oil, palmkernel oil or mixtures thereof. The sodium or potassium soaps of these acids can be used.

In many (but not all) cases, the total detergent active material may be present at from 2% to 60% by weight of the total composition, for example from 5% to 40% and typically from 10% to 30% by weight. However, one preferred class of compositions comprises at least 20%, most preferably at least 25% and especially at least 30% of detergent active material based on the weight of the total composition. optional ingredients

Compositions of the invention may be un-structured

(isotropic) or structured. Structured liquids of the invention may be internally structured whereby the structure is formed by the detergent active materials in the composition or externally structured, whereby the structure is provided by an external structurant.

Preferably compositions of the invention are internally structured.

Some of the different kinds of active-structuring which are possible are described in the reference H.A. Barnes, "Detergents", Ch.2. in K. Walters (Ed), "Rheometry:

Industrial Applications", J. Wiley & Sons, Letchworth

1980. In general, the degree of ordering of such systems increases with increasing surfactant and/or electrolyte concentrations. At very low concentrations, the

surfactant can exist as a molecular solution, or aε a solution of spherical micelles, both of these being isotropic. With the addition of further surfactant and/or electrolyte, structured (antisotropic) systems can form. They are referred to respectively, by various terms such as rod-micelles, planar lamellar structures,' lamellar droplets and liquid crystalline phases. Often, different workers have used different terminology to refer to the structures which are really the same. For instance, in European patent specification EP-A-151 884, lamellar droplets are called "spherulites". The presence and identity of a surfactant structuring system in a liquid may be determined by means known to those skilled in the art for example, optical techniques, various rheometrical measurements, x-ray or neutron diffraction, and sometimes, electron microscopy.

When the compositions are of lamellar structure then in many cases it is preferred for the aqueous continuous phase to contain dissolved electrolyte. As used herein, the term electrolyte means any ionic water soluble material. However, in lamellar dispersions, not all the electrolyte is necessarily dissolved but may be

suspended as particles of solid because the total electrolyte concentration of the liquid is higher than the solubility limit of the electrolyte. Mixtures of electrolytes also may be used, with one or more of the electrolytes being in the dissolved aqueous phase and one or more being substantially only in the suspended solid phase. Two or more electrolytes may also be distributed approximately proportionally, between these two phases. In part, this may depend on processing, e.g. the order of addition of components. On the other hand, the term "salts" includes all organic and inorganic materials which may be included, other than surfactants and water, whether or not they are ionic, and this term encompasses the sub-set of the electrolytes (water soluble materials) . The selection of surfactant types and their proportions, in order to obtain a stable liquid with the required structure will be fully within the capability of those skilled in the art. However, it can be mentioned that an important sub-class of useful compositions is those where the detergent active material comprises blends of different surfactant types. Typical blends usefu- for fabric washing compositions include those where the primary surfactant(s) comprise nonionic and/or a non-alkoxylated anionic and/or an alkoxylated anionic surfactant.

In the case of blends of surfactants, the. precise proportions of each component which will result in such stability and viscosity will depend on the type(s) and amount(s) of the electrolytes, as is the case with conventional structured liquids. Preferably though, the compositions contain from 1% to 60%, especially from 10 to 45% of a salting-out

electrolyte. Salting-out electrolyte has the meaning ascribed to in specification EP-A-79 646, that is salting-out electrolytes have a lyotropic number of less than 9.5. Optionally, some salting-in electrolyte (as defined in the latter specification) may also be

included, provided it is of a kind and in an amount compatible with the other components and the composition is still in accordance with the definition of the invention claimed herein. Some or all of the electrolyte (whether salting-in or salting-out), or any

substantially water insoluble salt which may be present, may have detergency builder properties. In any event, it is preferred that compositions according to the present invention include detergency builder material, some or all of which may be electrolyte. The builder material is any capable of reducing the level of free calcium ions in the wash liquor and will preferably provide the composition with other beneficial properties such as the generation of an alkaline pH, the suspension of soil removed from the fabric and the dispersion of the fabric softening clay material. Preferably the salting-out electrolyte comprises citrate. Examples of phosphorous-containing inorganic detergency. builders, when present, include the water-soluble salts, especially alkali metal pyrophosphates, orthophosphates, polyphosphates and phosphonates. Specific examples of inorganic phosphate builders include sodium and

potassium tripolyphosphates, phosphates and

hexametaphosphates. Phosphonate sequestrant builders may also be used. Examples of non-phosphorus-containing inorganic

detergency builders, when present, include water-soluble alkali metal carbonates, bicarbonates, silicates and crystalline and amorphous aluminosilicates. Specific examples include sodium carbonate (with or without calcite seeds), potassium carbonate, sodium and

potassium bicarbonates, silicates and zeolites.

In the context of inorganic builders, we prefer to include electrolytes which promote the solubility of other electrolytes, for example use of potassium salts to promote the solubility of sodium salts. Thereby, the amount of dissolved electrolyte can be increased

considerably (crystal dissolution) as described in UK patent specification GB 1 302 543.

Examples of organic detergency builders, when present, include the alkaline metal, ammonium and substituted ammonium polyacetates, carboxylates, polycarboxylates, polyacetyl carboxylates and polyhydroxysulphonates.

Specific examples include sodium, potassium, lithium, ammonium and substituted ammonium salts of

ethylenediaminetetraacetic acid, nitrilitriacetic acid, oxydisuccinic acid, CMOS, TMS, TDS, melitic acid, benzene polycarboxylic acids and citric acid.

Preferably the level of non-soap builder material is from 0-50% by weight of the composition, more preferred from 5-40%, most preferred 10-35%. In the context of organic builders, it is also desirable to incorporate polymers which are only partly dissolved, in the aqueous continuous phase as described in EP

301.882., This allows a viscosity reduction (due to the polymer which is dissolved) whilst incorporating a sufficiently high amount to achieve a secondary benefit, especially building, because the part which is not dissolved does not bring about the instability that would occur if substantially all were dissolved. Typical amounts are from 0.5 to 4.5% by weight.

It is further possible to include in the compositions of the present invention, alternatively, or in addition to the partly dissolved polymer, yet another polymer which is substantially totally soluble in the aqueous phase and has an electrolyte resistance of more than 5 grams sodium nitrilotriacetate in 100ml of a 5% by weight aqueous solution of the polymer, said second polymer also having a vapour pressure in 20% aqueous solution, equal to or less than the vapour pressure of a reference 2% by weight or greater aqueous solution of polyethylene glycol having an average molecular weight of 6000; said second polymer having a molecular weight of at least 1000. Use of such polymers is generally described in our EP 301,883. Typical levels are from 0.5 to 4.5% by weight.

The viscosity of compositions according to the present is preferably less than 1500 mPas, more preferred less than 1000 mPas, especially preferred between 30 and 900 mPas at 21 s^-1.

One way of regulating the viscosity and stability of compositions according to the present invention is to include viscosity regulating polymeric materials.

Viscosity and/or stability regulating polymers which are preferred for incorporation in compositions according to the invention include deflocculating polymers having a hydrophilic backbone and at least one hydrophobic side chain. Such polymers are for instance described in our copending European application EP 89201530.6

(EP 346 995).

Deflocculation polymers for use in detergent

formulations according to the present invention may be of anionic, nonionic or cationic nature. Anionic

deflocculating polymers are preferred.

The hydrophilic backbone of the polymer is typically a homo-, co- or ter-polymer containing carboxylic acid groups (or more preferably) salt forms thereof), e.g. maleate or acrylate polymers or co-polymers of these together or with other monomer units such as vinyl ethers, styrene etc. The hydrophobic chain or chains typically are selected from saturated and unsaturated alkyl chains, e.g. having from 5 to 24 carbon atoms and are optionally bonded to the backbone via an alkoxylene or polyalkoxylene linkage, for example a polyethoxy, polypropoxy or butyloxy (or mixtures of same) linkage having from 1 to 50 alkoxylene groups. Thus, in some forms, the side chain(s) will essentially have the character of a nonionic surfactant. Preferred anionic polymers are disclosed in our copending European patent application EP 89201530.6 (EP 346 995).

Preferably the amount of viscosity regulating polymer is from 0.1 to 5% by weight of the total composition, more preferred from 0.2 to 2%.

Compositions of the invention may advantageously

comprise a poly-hydric alcohol having from 1 to 5 carbon atoms per molecule. Preferred C_1-5 alcohols are di- or tri- alcohols comprising three or four carbon atoms per molecule. Especially preferred is the use of propylene glycol and glycerol. Preferably the level of C_1-5 poly-hydric alcohols is more than 1 % by weight of the composition, preferably more than 2 %, especially preferred more than 3 %.

Generally compositions of the invention will comprise less than 30 % by weight of the polyhydric alcohol, more preferred less than 20 %, especially preferred less than 15 %. Typical levels are from 4 to 10 % by weight of the composition. Compositions of the invention may also comprise

materials for adjusting the pH. For lowering the pH it is preferred to use weak acids, especially the use of organic acids is preferred, more preferred is the use of C 1-8 carboxylic acids, most preferred is the use of citric acid. The use of these pH lowering agents is especially preferred when the compositions of the invention contain enzymes such as amylases, proteases and lipolases. Apart from the ingredients already mentioned, a number of optional ingredients may also be present, for example lather boosters such as alkanolamides, particularly the monoethanolamides derived from palm kernel fatty acids and coconut fatty acids, fabric softeners such as clays, amines and amine oxides, lather depressants, inorganic salts such as sodium sulphate, and, usually present in very minor amounts, fluorescent agents, perfumes, germicides colourants and enzymes such as proteases, cellulases, amylases and lipases (including Lipolase (Trade Mark) ex Novo). Suitable examples of protease enzymes are Savinase (ex Novo), Maxatal (gist-brocades), Opticlean (ex MKC) or AP122 (ex Showa Denko), Alcalase, Maxatase, Esperase, Optimase, proteinase K and

subtilisin BPN. Suitable lipolases are for example

Lipolase (ex Novo), Amano lipases, Meito lipases,

Lipozym, SP 225, SP 285, Toyo Jozo lipase. Suitable amylases are for example Termamyl (TM of Novo) and

Maxamyl. Suitable cellulases include Celluzym (ex Novo). Amongst these optional ingredients, as mentioned

previously, are agents to which lamellar dispersions without deflocculating polymer are highly stability-sensitive and by virtue of the present invention, can be incorporated in higher, more useful amounts. These agents cause a problem because they tend to promote flocculation of the lamellar droplets. Examples of such agents are fluorescers like Blankophor RKH, Tinopal LMS, and Tinopal DMS-X and Blankophor BBM as well as metal chelating agents, especially of the phosphonate type, for example the Dequest range sold by Monsanto. Compositions of the invention preferably comprise from 10 -80 %% by weight of water, more preferably from 15-60%, most preferably from 20-50 %.

Liquid detergent compositions according to the invention are preferably physically stable in that they show less than 2% by volume phase separation upon storage for 21 days after preparation at 25°C.

Liquid detergent compositions according to the invention are preferably volume stable in that they show less than 25% preferably less than 10%, more preferably less than 5% volume increase during storage at a temperature between 20 and 37°C for a period of three months after preparation.

For obtaining good volume stability, preferably the compositions according to the present invention also comprise a second stabilising agent for the bleach component. Suitable stabilisers are well-known in art and include EDTA, Magnesium silicates and phosphonates such as for instance the Dequest range ex Monsanto and Naphthol ex Merck. Preferably the amount of these stabilising agents is from 0.05 to 5 % by weight of the composition, more preferred from 0.05 to 1% of the composition. Compositions of the present invention may comprise one or more bleach precursor agents. A well-known example of such an agent is TAED. Preferably the bleach precursor agent is present in the system in at least partly undissolved form. One way of ensuring that the precursor is present in undissolved form is to increase the amount of electrolyte in the composition, therewith reducing the solubility of the precursor in the system. Suitable electrolytes for this purpose are for instance the at least partially water soluble carbonate, sulphate and halogenide salts.

In use the detergent compositions of the inventention will be diluted with wash water to form a wash liquor for instance for use in a washing machine. The

concentration of liquid detergent composition in the wash liquor is preferably from 0.05 to 10 %, more preferred from 0.1 to 3% by weight.

To ensure effective detergency, the liquid detergent compositions preferably are alkaline, and it is

preferred that they should provide a pH within the range of about 7.0 to 12, preferably about 8 to about 11, when used in aqueous solutions of the composition at the recommended concentration. To meet this requirement, the undiluted liquid composition should preferably be of a pH above 7, for example about pH 8.0 to about 12.5. It should be noted that an excessively high pH, e. g. over about pH 13 , is less desirable for domestic safety. If hydrogen peroxide is present in the liquid composition, then the pH is generally from 7.5 to 10.5, preferably 8 to 10, and especially 8.5 to 10, to ensure the combined effect of good detergency and good physical and chemical stability. The ingredients in any such highly alkaline detergent composition should, of course, be chosen for alkaline stability, especially for pH-sensitive

materials such as enzymes, and a particularly suitable proteolytic enzyme. The pH may be adjusted by addition of a suitable alkaline or acid material.

Compositions according to the invention may be prepared by any method for the preparation of liquid detergent compositions. A preferred method involves the addition of metaborate to water, which optionally comprises one or more of the other ingredients of the formulation. The bleach materials are preferably added as a pre-dispersion .

The invention will now be illustrated by way of the following Examples. In all Examples, unless stated to the contrary, all percentages are by weight.

Example I

This example illustrates the stability of bleaches in aqueous systems containing bleach in combination with additive materials. The aqueous systems as used comprise the same relative amounts of ingredients that would be present in a corresponding ready to use aqueous liquid detergent composition. For example, composition A comprises 20 parts of bleach materials and 40 parts of water; a corresponding liquid detergent composition would comprise 20 parts of bleach, 40 parts of water and 40 (up to 100) parts of detergent active materials in combination with other ingredients. Although the

absolute stability of the bleach in the compositions without the detergent active materials can differ from the absolute stability of the bleach in the

corresponding detergent compositions, it is believed that the comparison of systems without detergent active materials provides a good indication of the relative bleach stabilities of compositions with detergent active materials.

Compositions A-D were prepared by adding the ingredients to water in the listed order under stirring. The result is a physically instable perborate dispersion from which the undissolved bleach materials will sediment. The continuous electrolyte phase containing the dissolved ingredients was isolated and assessed for bleach content and bleach stability. Since only the dissolved amount of bleach will contribute to the decomposition of the bleach, the results obtained for the separated

electrolyte phase are representative for the stability of the total bleach stability in the system. The amount of dissolved bleach in the separated

electrolyte phase was measured by iodometric titiations, the half-life time was determined on the basis of measurements of the amount of solubilised bleach in the-separated electrolyte phase as a function of time.

The following results were obtained:

TABLE 1 Perborate solubility and solubility and stability at 37 °C.

COMPONENT (Wt parts) COMPOSITION

A B C D

Na-metaborate ¹) - - 2.6 2.6 - -

Glycerol - - - - 3.5 3.5

Na-perborate.4H₂O 20 20 20 20 water 40 40 40 40

PH²) 9.8 11.0 10.2 9.6 dissolved perborate³) 2.10 1.85 1.84 5.3 t(1/2) days <<1 16⁴) 2 0.82 decomposed bleach⁵) >1.65 0.057 0.46 3.24 1) Na metaborate 4H₂O ex BDH Chemicals

2) of total system at t=0

3) wt % of dissolved perborate in isolated electrolyte phase at t=0.

4) extrapolated.

5) in weigth % of the total bleach in the isolated

electrolyte phase after 1 day.

These results illustrate that composition A, comprising the bleach material in water in the absence of

metaborate, results in a high level of dissolved bleach in the separated electrolyte phase and in a very short life time of the dissolved bleach material. Composition D containing glycerol and bleach in water in the absence of metaborate also provides a high level of dissolved bleach which decomposes in less than 1 day. Composition B contains metaborate in combination with bleach

materials, this results in a low level of dissolved bleach and a long life time of the dissolved bleach. The total amount of decomposed bleach is low. Composition C; which additionally comprises Glycerol has the advantage of a lower pH; this is especially preferred for enzyme containing liquid detergent compositions. Also this composition is more stable than the corresponding composition without metaborate. These results indicate that liquid detergent compositions corresponding to the tested compositions would have a greater bleach

stability in the presence of metaborate.

Example 2

Compositions were prepared and the amount of dissolved bleach and its stability was measured as in example 1.

The following results were obtained:

TABLE 2 Bleach stability at 37°C

COMPONENT (Wt parts) COMPOSITION

E F G H I J

Na-metaborate.4H₂O 2.6 2.6 2.6 2.6 2.6 2.6

Glycerol - - - - - - - - - - 3.5 citric-acid - - 0.93 1.53 - - - - 0.31 sulphuric acid - - - - 0.65 1.13 - -

Na-perborate.4H₂O 20 20 20 20 20 20 water 40 40 40 40 40 40

PH 11.0 9.0 8.0 9.0 8.0 9.0 dislvd bleach % 1.85 2.08 3.52 2.2 3.88 2.15 t(1/2) Says 16*) 15*) 6 1.2 <<1 6 decomposed bleach % 0.057 0.069 0.29 0.95 >2.9 0.18

*) extrapolated.

This example illustrates the effect of pH lowering agents on bleach stability. Tests F-G and J show that the pH of a bleach and metaborate composition can advantageously be decreased by using citric acid; the obtained compositions are of acceptable stability. Lowering the pH of the compositions with sulphuric acid (tests H-I) leads to instability of th bleach especially at low pH values.

Example 3

Compositions were prepared and assessed for bleach stability as in example 1. The following results were obtained

Table 3 Bleach stability at 37 °C

COMPONENT (wt parts) COMPOSITION

K L M

Na-metaborate.4H₂O 5.0 5.0 5.0

DEQUEST 2066 - - 0.2 - -

Mg-trisilicate - - - - 0.2

Na-perborate.4H₂O 20 20 20

water 40 40 40

PH 11.1 11.1 11.1

disvld bleach % 1.83 1.71 2.03

t(1/2) days 52 80*) 65

decomposed bleach % 0.018 0.011 0.016 *) extrapolated.

These results show that the stability of bleach in the presence of metaborate can even be further improved by addition of a further stabiliser such as Dequest or Mg-silicate. Example 4

The following liquid detergent compositions may be formulated by adding the ingredients to water in the listed order:

Ingredient Basic formulation (% wt)

1 2 3 4

Na DOBS 8.5 8.5 7.5 7.5 4.3

Synperonic A7 2.0 2.0 3.0 3.0 6.0

Na Oleate 2.7 10.8 8.1 10.8 - -

Glycerol 5.0 5.0 5.0 5.0 5.0

Na-metaborate 3.5 3.5 3.5 3.5 3.5

STP 22 22 22 22 22

Na-perborate.4H₂O 15 10 12 10 20

Polymer *) 1.0 1.0 1.0 0.5 2.0 water - - - - - - - - - up to 100- - - - - - - - -

*) Polymer A-2 as described in EP 89201530.6

(EP 346 995).

Example 5 the following formulations may be prepared as in example 4:

Table 5

Ingredient Composition %wt

1 2

Na DoBS 9.1 17.3

Synperonic A7 3.6 1.8

Na Stearate - - 0.9

Glycerol 8.1 3.0

NaOH 1.0 - -

Na-metaborate 5.8 2.0

Na-perborate 20 10

Na-citrate - - 5.0

citric acid 1.5 - -

Zeolite A4 25.3 30.0

NaCMC - - 0.3

Tinopal CBS-X - - 0.13

Perfume - - 0.22

Alcalase 2.34L - - 0.5

Polymer *) 0.5 0.5

water - -to 100%- - - - - - *) polymer A-11 as described in EP 89201530.6

(EP 346 995).

Example 6

The following detergent compositions may be prepared as in example 4.

Ingredient Composition % wt

1 2

NaDoBS 10.2 - -

K DOBS - - 10.7

Synperonic A7 19.3 19.3

Na Oleate 10.3 - -

K Oleate - - 10.3

Glycerol 5.0 5.0

Na-metaborate 3.5 3.5

Na-perborate.4H₂O 10.0 15.0

Na-citrate 2aq 10.0 - -

Na₂CO₃ - - 4.0

Sokolan CP5 2.5 - -

Dequest 2066 0.4 - -

Mg-silicate - - 0.4

Silicon DB 100 0.3 0.3

Tinopal CBS-X 0.5 0.5

Savinase 0.1 0.1

Amylase 0.1 0.1

Perfume 0.1 0.1

Dye 0.3 0.3

Polymer *) 1.0 1.0

*) polymer A-11 as disclosed in EP 89201530.6

(EP 346 995). Examples 7-12

The following compositions were prepared by adding the

electrolyte together with the minor ingredients except

for the perfume and the enzymes to water of elevated

emperature, followed by the addition of the detergent ctive material as a premix under stirring and

thereafter cooling the mixture and adding the enzymes,

perfumes and the bleach.

INGREDIENT (% WT) 7 8 9 10 11 1

Na-Dobs 21 21 23.3 21 21 2

Synperonic 7 9 9 10 9 9

Glycerol 3.5 - - 3.9 - - 3.5

Metaborate 2.6 2.6 2.9 2.6 2.6

Nacitrate/ Citric acid¹) 9.8 9.8 11.1 9.8 9.8

Dequest 2060S (as 100%) 0.4 0.4 0.4 0.4 0.4

Na-perborate tetrahydrate³) 20 20 - - 20 20 -

Na-perborate monohydrate - - - - 7.2 - - - - 1

Enzyme, Alcalase 0.8 0.8 0.8 0.8 0.8

CaCl₂.2H₂O 0.2 0.2 0.2 0.2 0.2

Fluorescer, Tinopal CBSX 0.1 0.1 0.1 0.1 0.1

Silicon, Dow Corning DB100 0.3 0.3 0.3 0.3 0.3

Perfume 0.3 0.3 0.3 0.3 0.3 deflocculating polymer⁴) 1 1 1.1 1 1 ethanol - - - - - - 2.5 2.5 - water - - - - - - - - - - - balance- - - - - - - - - - PH 9 9 9 9 9 1) This mixture is used to adjust the final pH.

2) Expressed as % of analysed enzyme level in the fresh

sample.

3) As 100 % perborate, added as a dispersion (Proxsol ex

ICI, approximate 65% perborate dispersion in water with an average perborate particle size of 40 micrometer).

4) Deflocculating polymer of formula I of EP 346 995,

wherein x=50, y=O, R⁵=H, R⁶=CH₃, R¹= -CO-O, R² and R³

are absent, R⁴= -C₁₂H₂₅, mW= 7,500. 5) wt% -approximate- of total perborate, obtained by removal of the undissolved bleach particles by mild centrifugation.

6) Not measured

The obtained products had the following characteristics:

8 10 11 12

Volume stability (% volume 4 3 0 0 0 0 increase, 3 months 25 °C)

clear layer separation no no no no no no

(3 weeks 37 °C)

solid sedimentation no no no no no no

(3 weeks 37 °C)

Viscosity 21 s^-1 1,350 710 800 850 1330 760

Viscosity 10-⁴ s^-1 200,000 n.m⁶) n.m n.m n.m n.m dissolved perborates⁵) 3 1.5 8 1.5 3 6 bleach activity 99 99 96 98 98 97

(2 months ambient T)

enzyme activity 65 62 76 83 70 n.

(2 months ambient T)²)

Example 13

The composition of example 7 was prepared, while CaCl₂ was used at a level of 1% in combination with 0.8% of enzymes, whereby the following types of enzymes were used.

Esperase liquid (Esperase L8.0 ex Novo)

Savenase liquid (Savinase 16.0 LDX ex Novo)

Savinase slurry (Savinase 16.0 SL ex Novo).

Alcalase liquid (Alcalase 2.34 LDX ex Novo)

It was found that the enzyme stability was dependant on the type of enzyme used, whereby an increase in enzyme stability was found in the following order:

Esperase > Savinase slurry > Savinase liquid > Alcalase

Claims (10)

1. A ready to use liquid detergent composition

comprising an aqueous base, a bleach material, from 2-60% by weight of detergent active materials and a metaborate electrolyte.

2. A liquid detergent composition according to claim 1, wherein the bleach material is only partially soluble in the composition, and wherein preferably the bleach material comprises a perborate and/or percarbonate material.

3. A liquid detergent composition according to claim 1, comprising an amount of bleach corresponding to 0.1- 15% by weight of active oxygen and/or 1-40% by weight of bleach material.

4. A liquid detergent composition according to claim 1, comprising from 0.1-10% by weight of metaborate electrolyte and wherein preferably the level of metaborate is determined by measuring the boron content of the aqueous phase of the formulation and calculating the corresponding level of metaborate at a standard pH of 11.

5. A liquid detergent composition according to claim 1, comprising from 1-60% by weight of salting-out electrolytes, said salting-out electrolyte

preferably comprising a citrate electrolyte.

6. A liquid detergent composition according to claim 1, comprising 5-50% by weight of a non-soap builder material.

7. A liquid detergent composition according to claim 1 comprising from 0.1 to 5% by weight of a

deflocculating polymer.

8. A liquid detergent composition according to claim 1 having a pH of from 8.0 to 12.5, a viscosity of less than 1,500 mPas at 21 s^-1, said composition also being physically stable and volume stable.

9. A ready to use liquid detergent composition

comprising an aqueous base, a bleach material, from 2-60 % by weight of a detergent active material and a boron electrolyte obtainable by using a metaborate electrolyte.

10. Method of washing, wherein a liquid detergent

composition in accordance with claims 1-9 is diluted with water to form a wash liquor preferably for use in a washing machine.