DE3888116T2 - Bleach. - Google Patents

Description

The present invention relates to detergent compositions. In particular, it relates to bleaching detergent compositions suitable for use in laundry washing, and most particularly to bleaching detergent compositions containing organic peroxyacid bleach precursors. The detergent compositions provide safe and effective peroxygen bleaching of fabrics over a wide range of temperatures, washing conditions, washing machines and fabric types.

The removal of oxidizable stains from either hard surfaces or fabrics using peroxygen bleaches at temperatures below 60ºC is a well-known method and usually involves the use of organic peroxyacids. The most commonly used peroxyacid is peracetic acid, which is normally generated in situ in the bleach or wash liquor by the reaction of alkaline hydrogen peroxide with a peroxyacid precursor (the so-called bleach activator). However, peroxyacids containing more than 2 carbon atoms in the acyl group have also been described and proposed for this purpose and GB-A-864 798, CA-A-635 620, US-A-4 100 095, US-A-4 119 660, US-A-4 126 573, EP-A-0 068 547 and EP-A-0 120 591 all relate to the formation, stabilization or use of such materials.

Recently, as described in EP-A-0 068 547 and EP-A-0 120 591, it has been found that the choice of the chain length of the aliphatic residue of the peroxyacid enables the peroxyacid to be concentrated in the area where stain removal is required. Thus, for removing spurious dyes in large volume solution, a "hydrophilic" bleach species is satisfactory, whereas for stains on solid surfaces, a bleach species which exhibits a more hydrophobic character and therefore a tendency to migrate to the solid-liquid interface may be more advantageous. Bleach activator compositions which form these so-called "hydrophobic" bleach species are described in detail in EP-A-0 068 547 and EP-A-0 120 591.

It has now been established that under certain conditions of use the "hydrophobic" class of bleaches and bleach activators can have an adverse effect on certain types of water-insoluble polymer-based substrates, typically those containing unsaturated residues or a high degree of polymer cross-linking. Although the reasons for this are not fully understood, the effect appears to be related to a side reaction of the main bleaching process, which has a single electron generating free radical mechanism.

It has also been found that under certain conditions of use, peroxygen bleaches and bleach activators, both of the "hydrophobic" and peracetic acid precursor classes, can have an adverse effect on the color fastness of fabrics washed with them.

The present invention therefore provides bleaching and detergent compositions which contain a hydrophobic bleach activator component incorporated therein and which are safe and effective in use over the full range of use conditions and substrate types, including those containing unsaturated or cross-linked polymeric moieties. The invention also provides bleaching detergent compositions which exhibit improved safety to dyed fabrics and which additionally exhibit exceptional effectiveness in preventing dye transfer.

Unless otherwise indicated, all percentages and ratios herein are by weight of the total composition.

According to the present invention there is provided a detergent composition comprising

(a) 1% to 75% by weight of organic surfactant selected from anionic, nonionic, cationic, ampholytic and zwitterionic surfactants and mixtures thereof,

(b) a peroxygen bleach component comprising

i) 0.5% to 40% by weight of peroxygen bleach and

ii) 0.1% to 25% by weight of peroxyacid bleach precursor, and

(c) 0.01% to 2% by weight of an antioxidant, which antioxidant is incorporated into a solid, amorphous, glassy carrier material made of polyvinylpyrrolidone (PVP), the weight ratio of antioxidant:PVP being in the range of 5:1 to 1:10.

The detergent compositions of the invention contain as essential components an organic surfactant, a peroxygen bleach component and an antioxidant incorporated in a solid, amorphous, glassy carrier material of polyvinylpyrrolidone.

Preferred antioxidants for use herein are of the phenolic or phenol ester classes, although other types of antioxidants such as the hindered amine type light stabilizers based on 2,2,6,6-tetramethylpiperidine derivatives or 1,2-dihydro-2,2,4-trimethylquinoline derivatives are also suitable herein.

Among the phenolic antioxidants preferred for use herein are those compounds having the general formula II:

wherein R is selected from H, OH, C₁-C₁₈ alkyl and alkenyl, C₅-C₈ cycloalkyl, aryl, aralkyl, araloxyalkyl or arylthioalkyl, each radical having up to 4 carbon atoms in the alkyl radical, which cycloalkyl and aryl radicals are unsubstituted or substituted by one or more identical or different substituents selected from C₁-C₄ alkyl and alkoxy groups; R₁ is selected from H, OH, C₁-C₁₈ alkyl and benzotriazole and aminotriazine derivatives; and R₂ is selected from H, OH, CO₂H and salts and esters thereof, benzotriazole and aminotriazine derivatives, C₁-C₁₈-alkyl and -alkenyl, C₁-C₄-alkylthio and C₁-C₄-alkylthio-(C₁-C₄-alkylene and C₁₋₁₄-alkyloxy) which are alkyl or Alkenyl radicals are substituted or unsubstituted by one or more C₁-C₄ alkoxy radicals or by one or more carboxylic acid or phosphonic acid radicals or salts or esters thereof. However, when R and R₁ are both H, R₂ is preferably OH or a C₁-C₄ alkyloxy radical.

In the compounds of formula II, R is preferably selected from methyl, ethyl, isopropyl, sec-butyl, tert-butyl, tert-amyl, 1,1,3,3-tetramethylbutyl, α,α-dimethylbenzyl, cyclohexyl and 1-methylcyclohexyl, R₁ is preferably selected from H, methyl, ethyl, isopropyl, sec-butyl and tert-butyl; and R₂ is preferably selected from OH, methyl, ethyl, isopropyl, sec-butyl, tert-butyl, tert-amyl, 1,1,3,3-tetramethylbutyl, α,α-dimethylbenzyl, -CH₂CO₂M, -CH₂CH₂CO₂M, -CH₂SCH₂CO₂M and -CH₂SCH₂CH₂CO₂M, where M is selected from H, alkali metal and alkaline earth metal and ammonium cations and C₁₋₁₈-alkyl and alkenyl ester radicals. In the most preferred embodiments, R and R₁ are both tert-alkyl radicals branched at the α-carbon, especially tert-butyl radicals.

Also suitable here are polynuclear phenolic antioxidants which have the general formula III:

wherein each R is independently selected from H, OH, C₁-C₁₈ alkyl and alkenyl, C₅-C₈ cycloalkyl, aryl, aralkyl, araloxyalkyl or arylthioalkyl, each having up to 4 carbon atoms in the alkyl group, which cycloalkyl and aryl groups are substituted or unsubstituted by one or more identical or different substituents selected from C₁-C₄ alkyl and alkoxy groups; each R₁ is independently selected from H, OH and ortho- or para-substituted C₁-C₁₈ alkyl; each R₄ independently from ortho- and para-substituted C₁-C₄-alkylene, C₁-C₄-alkyleneoxy-(C₁-C₄)-alkylene- and C₁-C₄alkylenethio-(C₁-C₄)alkylene radicals, which C₁-C₄alkylene radicals are optionally substituted with one or more C₁-C₄alkyleneoxycarbonyl or mono- or di-(C₁-C₄alkyleneoxy)phosphonyl radicals, or wherein R₄ represents a direct bond; n is from 2 to 4; and wherein B is a di-, tri- or tetravalent bridging radical, preferably selected from thio-, carboxy-, phosphonoxy-, isocyanurate, borate, sulfonyl and di-, tri- and tetravalent organic radicals. Suitable organic radicals may have a single bridging carbon or a chain of up to 6 carbons in a linear bridge. In both cases, however, any non-bridging carbon valencies are preferably saturated by H or by one or more alkyl radicals with a total of up to 12 carbon atoms.

The bridging residue B is thus an n-valent group that connects the n phenolic residues of the polynuclear antioxidant. If there is any doubt about the distinction between the B and R4 residues, the bridging residue is considered to be the smallest possible n-valent group.

In the compounds of formula III, R is preferably selected from methyl, ethyl, isopropyl, sec-butyl, tert-butyl, tert-amyl, 1,1,3,3-tetramethylbutyl, α,α-dimethylbenzyl, cyclohexyl and 1-methylcyclohexyl, R₁ is preferably selected from methyl, ethyl, isopropyl, sec-butyl and tert-butyl, R₄ is preferably selected from C₁-C₄alkylene optionally substituted with C₁-C₄alkyleneoxycarbonyl, and B is preferably selected from thio, methylene optionally substituted with a linear or branched C₁-C₁₂alkyl radical, tri- or tetravalent C₃-C₆hydrocarbon and tetravalent carbon. In most preferred embodiments, R and R₁ are both tert-alkyl radicals branched at the alpha carbon, especially tert-butyl radicals.

Another group of antioxidants which are particularly useful herein is formed by the oligomeric antioxidants which have the general formula IV:

wherein each R is independently selected from H, OH, C₁-C₁₈ alkyl and alkenyl, C₅-C₈ cycloalkyl, aryl, aralkyl, aryloxyalkyl or arylthioalkyl, each having up to 4 carbon atoms in the alkyl group, which cycloalkyl and aryl groups are unsubstituted or substituted by one or more identical or different substituents selected from C₁-C₄ alkyl and alkoxy groups; each R₁ is independently selected from OH or ortho- or para-substituted C₁-C₁₈ alkyl; R₅ is selected from C₂-C₁₀ alkylene and cycloalkylene groups; and represents a numerical average from 1 to 10.

A particularly preferred antioxidant of this type has the above general formula IV, wherein R is tert-butyl, R₁ is 4-methyl, R₅ is dicyclopentadienediyl and i is averaged from 1 to 3.

Phenolic ester antioxidants are also suitable for use herein. Of this class, a preferred antioxidant is a full or partial ester of a boric acid selected from orthoboric acid (H3BO3), metaboric acid (HBO3), pyroboric acid (H4B2O5), boronic acid (H3BO2) and borinic acid (H3BO) wherein at least one esterifying group is a phenol having the general formula II or III. Particularly preferred antioxidants of this class are those wherein at least one esterifying group is a phenol having the general formula II wherein R and R1 are selected from C4 -C10 tert-alkyl radicals branched at the alpha carbon and R2 is is selected from H and C₁-C₄-alkyl radicals. The boron esters may be fully arylated or they may be mixed esters containing both phenol ester units and mono- or dialiphatic alcohol or glycol ester units, in particular those consisting of C₁-C₁₂-alkanol or C2 -C12 alkylene glycol esterifying units. Partial orthoborate esters, wherein boron is bonded to one phenoxy group and the other two bonds to hydroxyl groups, are also useful herein. Methods for preparing these general classes of materials are set forth in US-A-3,356,707 and US-A-3,359,298.

Particularly preferred antioxidants here are: 4-methyl-2,6-di-tert.butylphenol, 2,2'-methylenebis(4-methyl-6- -tert.butylphenol), 4,4'-methylenebis(2,6-di-tert.butylphenol) 2,2'-methylenebis(4-methyl-6-(1-methylcyclohexyl)phenol), 4,4'-thiobis(6-tert.butyl-3-methylphenol), 4,4'-butylidene-bis- (6-tert.butyl-3-methylphenol), 6-tert.butylhydroquinone, pyrogallol, 2,2'-methylene-bis(4-methyl-6-nonylphenol), 2,2'-iso-nonylene-bis(2,4-dimethylphenol), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, tetrakis[methylene-3- (3',5'-di-tert-butyl-4'-hydroxyphenylpropionate)methane, the compounds of formula II wherein R and R₁ are both tert-butyl and R₂ is selected from CH₂SCH₂CO₂H, CH₂CH₂CO₂H and the C₁₈-alkyl esters thereof, tris-(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, the compound of formula IV wherein R is tert-butyl R₁ is 4-methyl, R&sub5; Dicyclopentadienediyl and m is on average about 1, 2,4-bis- (n-octylthio)-6-(4-hydroxy-3,5-di-tert.butylanilino)-1,3,5-triazine, 2-(2'-hydroxy-3'-butyl-5'-methylphenyl)-5-chlorobenzotriazole, tri(4-methyl-2,6-di-tert.butylphenyl)metaborate, tri(4-methyl-2,6-di-tert.butylphenyl)orthoborate, 2,6-di-tert.butylphenyl-di-isopropylorthoborate, 4-methyl-2,6-di-tert.butylphenyldi-isopropylorthoborate, di(4-methyl-2,6-di-tert.butylphenyl)-n-butylorthoborate, di-(2,6-tert.butylphenyl)-n-butylorthoborate and 4-Methyl-2,6-di-tert.butylphenyl-di-n-butylorthoborate selected.

Hindered amine type stabilizers useful herein are described in BE-A-734 436, GB-A-1 390 251, GB-A-1 390 252 and GB-A-1 433 285 and preferably have the general formula V

wherein R¹ and R² independently represent C₁-C₄alkyl, preferably CH₃, n is from 1 to 4 and is preferably 2, X is H, C₁-C₄alkyl, preferably H, and R³ is an acyl or polyacyl radical having n acyl groups which is derived from an aliphatic or aromatic carboxylic acid or polycarboxylic acid. However, stabilizers in which X is O or OH and ammonium salts of V are also suitable. Particularly preferred hindered amine type stabilizers include bis-(2,2,6,6-tetramethyl-4-piperidyl) sebacate, which is commercially available under the trade name Tinuvin (Registered Trademark) 770, and bis-(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, which is commercially available under the trade name Tinuvin (Registered Trademark) 292.

The peroxygen bleach component herein comprises a peroxyacid bleach precursor or a bleach activator component. The bleach activator component preferably comprises from 0.1% to 15%, more preferably from 0.25% to 5%, by weight of a hydrophobic peroxyacid bleach precursor of the general formula I

Ac - L I,

wherein Ac represents the acyl radical of an organic carboxylic acid, which comprises an optionally substituted, linear or branched C6-C20 alkyl or alkenyl radical or a C6-C20 alkyl-substituted aryl radical, and L represents a leaving group whose conjugate acid has a pKa value in the range of 4 to 13.

A highly preferred group of bleach activators herein has the general formula I, wherein Ac is R₅CO- and R₅ is a linear or branched alkyl group having 6 to 20, preferably 6 to 12, more preferably 7 to 9, carbon atoms, and wherein the longest linear alkyl chain extending therefrom and including the carbonyl carbon contains from 5 to 18, preferably 5 to 10 carbon atoms, wherein R₅ is optionally substituted by Cl, Br, OCH₃ or OC₂H₅ (preferably in the alpha position to the carbonyl radical).

In the above formula I, the leaving group L has a pKa value (of the conjugate acid) in the range of 4 to 13, preferably 8 to 10. Examples of leaving groups are those having the formula

wherein Z is H, R¹ or halogen, R¹ being an alkyl group having 1 to 4 carbon atoms, x is 0 or an integer from 1 to 4, and Y is selected from SO₃M, OSO₃M, CO₂M, N⁺(R¹)₃Q⁻ and N⁺(R¹)₂-O⁻, wherein M is H, alkali metal, alkaline earth metal, ammonium or substituted ammonium, and Q is a halide or methosulfate.

The preferred leaving group L has the formula (a) wherein Z is H, x is 0 and Y is a sulfonate, carboxylate or dimethylamine oxide residue.

Highly preferred materials are sodium 3,5,5-trimethylhexanoyloxybenzenesulfonate, 3,5,5-trimethylhexanoyloxybenzoic acid and its sodium salt, sodium 2-ethylhexanoyloxybenzenesulfonate, sodium nonanoyloxybenzenesulfonate and sodium octanoyloxybenzenesulfonate, in each case the acyloxy group is preferably p-substituted.

A second highly preferred group of Bleach activators have the general formula I, wherein Ac has the formula R₅(AO)mXA, wherein R₅ is a linear or branched alkyl or alkylaryl group having 6 to 20, preferably 6 to 15 carbon atoms in the alkyl radical, where R₅ is optionally substituted by Cl, Br, OCH₃ or OC₂H₅, AO is oxyethylene or oxypropylene, m is from 0 to 100, X is O, NR₁ or CO-NR₁, and A is CO, CO-CO, R₆-CO, CO-R₆-CO or CO-NR₁-R₆-CO, wherein R₅ is C₁-C₄-alkyl and R₆ is Alkylene, alkenylene, arylene or alkarylene having 1 to 8 carbon atoms in the alkylene or alkenylene radical. Bleach activator compounds of this type include carboxylic acid derivatives of the formula R₅(AO)mOCOL, succinic acid derivatives of the formula R₅OCO(CH₂)₂COL, glycolic acid derivatives of the formula R₅OCH₂COL, hydroxypropionic acid derivatives of the formula R₅OCH₂CH₂COL, oxalic acid derivatives of the formula R₅OCOCOL, maleic and fumaric acid derivatives of the formula R₅OCOCH=CHCOL, acylaminocaproic acid derivatives of the formula R₅CONR₁(CH₂)₆COL, acylglycine derivatives of the formula R₅CONR₁CH₂COL, and amino-6-oxocaproic acid derivatives of the formula R₅N(R₁)CO(CH₂)₄COL. Above, m is preferably from 0 to 10 and R₅ preferably represents C₆-C₁₂, more preferably C₆-C₁₀ alkyl when m is zero and C₉-C₁₅ alkyl when m is other than zero. The leaving group L is as defined above.

The bleach activator component of the present compositions may also contain from 0.5% to 10%, preferably from 1% to 6%, by weight of a peroxyacid bleach precursor which is not one of the hydrophobic bleach activators described above, for example peracetic acid bleach precursors such as tetraacetylethylenediamine, tetraacetylmethylenediamine, tetraacetylhexylenediamine, sodium p-acetoxybenzenesulfonate, tetraacetylglycouril, pentaacetylglucose, octaacetyllactose and methyl O-acetoxybenzoate.

The bleach activator component may also comprise a mixture of peracetic acid bleach precursor and a compound of general formula I. Preferred mixtures have a weight ratio of about 10:1 to 1:1 (non-hydrophobic bleach activator:hydrophobic bleach activator).

The bleach activator is usually in the form a particulate composition comprising from about 40% to about 99%, preferably from about 50% to about 95% by weight thereof, of the bleach activator compound together with a binder or agglomerating agent making up the balance, but preferably present in an amount of from about 1% to about 20% by weight of the activator composition. Additionally, the particles may contain a solid diluent. The agglomerating agent may take the form of a carrier in which the bleach activator and, if present, the diluent are dispersed, or the agglomerating agent may simply serve to promote physical adhesion of the components of the bleach activator composition. Alternatively, the agglomerating agent may serve as an encapsulating or coating agent for the bleach activator. Preferred agglomerating agents and diluents are described in EP-A-0 099 197 and EP-A-0 106 634.

Suitable organic carriers are selected from polyethylene glycols having a molecular weight greater than about 1000, C12-C24 fatty acids and esters and amides thereof, polyvinylpyrrolidones, particularly those having a molecular weight (viscosity average) in the range of about 1500 to about 1,500,000, more particularly from about 3000 to about 700,000, and C14-C24 fatty alcohols ethoxylated with about 14 to about 100 moles of ethylene oxide. Suitable inorganic carriers include the amorphous phosphate glasses described in EP-A-0 057 088. Preferred diluents are inorganic and include alkali metal, alkaline earth metal and ammonium sulfates and chlorides, neutral and acidic alkali metal carbonates, orthophosphates and pyrophosphates and crystalline alkali metal polyphosphates. Suitable water-insoluble but dispersible diluents include the finely divided natural and synthetic silicon dioxides and silicates, especially smectite-type and kaolinite-type clays such as sodium and calcium montmorillonite, kaolinite itself, aluminosilicates and magnesium silicates and fibrous and microcrystalline celluloses. Suitable adhesive materials include the organic carrier materials described above, water, aqueous solutions or Dispersions of the inorganic diluent materials described above, anionic surfactants, film forming polymers and solutions and latices thereof, for example sodium carboxymethylcellulose, methylcellulose, poly(oxyethylene), polyvinyl acetate, polyvinyl alcohol, dextrins, ethylene-vinyl acetate copolymers and acrylic latices. Other suitable polymers include the homopolymers and copolymers of acrylic acid, hydroxyacrylic acid or methacrylic acid, which in the case of the copolymers have at least 50% by weight and preferably at least 80% by weight of units derived from the acid. The most preferred polymer is sodium polyacrylate. Other specifically preferred polymers are the homopolymers and copolymers of maleic anhydride, particularly the copolymers with ethylene, styrene and vinyl methyl ether. These polymers are commercially available under the trade names Versicol (registered trademark) and Gantrez (registered trademark). Other suitable polymers include the cellulose sulfate esters such as cellulose acetate sulfate, cellulose sulfate, hydroxyethyl cellulose sulfate, methyl cellulose sulfate and hydroxypropyl cellulose sulfate.

The bleach activator composition can be prepared by extrusion, for example by means of a radial extruder as described in EP-A-0 062 523, by agglomeration in a drum agglomerator such as a pan agglomerator, or in a mixing agglomerator such as a Schugi mixer, or a fluidized bed and the like, as described for example in EP-A-0 106 634, or by spray drying as described for example in EP-A-0 174 132. Preferred drum and mixing agglomeration processes are described in Particle Size Enlargement, C.E. Capes, Handbook of Powder Technology, Vol. 1, pages 52-83 and 83-96, respectively.

The antioxidant component of the present compositions is incorporated in a solid, amorphous, glassy carrier material of polyvinylpyrrolidone, wherein the weight ratio of antioxidant to polyvinylpyrrolidone is in the range of from about 5:1 to about 1:10, preferably from about 3:1 to about 1:6, more preferably from about 2:1 to about 1:3. From the point of view For reasons of antioxidant storage stability, detergent performance and substrate safety, polyvinylpyrrolidones having a molecular weight of from about 3,000 to about 55,000, more preferably from about 8,000 to about 40,000, are preferred, with molecular weights being measured as viscosity averages (see V. Bühler and U. Klodwig, Acta Pharmaceutica Technologica 30(4), 1984, 317-323, Equation 10). The antioxidant can be incorporated into polyvinylpyrrolidone by dissolving the components in a mutual solvent such as ethanol, followed by solvent evaporation, or by preparing a co-melt of the individual components, followed by cooling, or by melting the individual components together at elevated temperature. Thereafter, the material is preferably comminuted to a weight average particle size of from about 2 mm to about 0.05 mm, preferably from about 1 mm to about 0.2 mm. The comminuted material may then be mixed with a diluent as described above, the preferred diluent being a water-soluble inorganic diluent, for example an alkali metal sulfate, and the mixture is then coated with an organic coating or agglomerated with an agglomerating material such as a C12-C24 fatty acid ester or amide, a paraffinic or microcrystalline wax, or in highly preferred embodiments, a polyethylene glycol having a molecular weight of about 1500 to about 8000. The finished agglomerate typically comprises about 20% to 94% of the antioxidant/polyvinylpyrrolidone mixture, about 5% to about 60% of the diluent, and about 1% to about 20% of the coating material or agglomerating material. Alternatively, the antioxidant/polyvinylpyrrolidone mixture can be comminuted to a particle size of from about 2 mm to about 0.05 mm, preferably from about 1 mm to about 0.2 mm and then incorporated into or coated on the bleach activator agglomerate, for example, polyethylene glycol or a C₁₂-C₂₄ fatty acid serving as an agglomerating agent or an adhesive agent. When incorporated directly into the particulate bleach activator mixture, the amount of antioxidant, based on the weight of the activator composition, is preferably from about 0.1% to about 35%, more preferably from about 0.5% to about 10%, by weight thereof.

An essential feature of the present invention is the requirement that the antioxidant be incorporated into a solid, amorphous, glassy carrier material of polyvinylpyrrolidone. This is important from the standpoint of storage stability of the antioxidant and to achieve optimum color fidelity and substrate safety. Preferably, the antioxidant is present in the PVP in the form of a solid solution. The physical form of the antioxidant/PVP mixture can be easily verified by hot stage microscopy (no evidence of birefringence due to the crystalline structure), differential scanning calorimetry (absence of endothermic discrete antioxidant melting), scanning electron microscopy and optical microscopy (glassy morphology - in which conchoidal fractures are a major feature) and X-ray diffraction (no evidence of strong diffraction lines typical of the crystalline antioxidant).

The amount of antioxidant in the total detergent composition comprises 0.01 wt% to 2 wt%, more preferably 0.1 wt% to 1 wt%. The amount of peroxyacid bleach precursor in the total composition comprises 0.1 wt% to 25 wt%, most preferably 0.75 wt% to 11 wt%. The molar ratio of peroxygen bleach to bleach activator is preferably at least about 1.5:1.

The detergent compositions of the invention may take the form of a conventional laundry detergent composition for the main wash cycle or of a laundry additive composition for use in conjunction with a separate main wash cycle detergent composition. In either case, however, preferred compositions will usually contain from about 1% to about 75%, preferably from about 5% to about 40%, more preferably from about 8% to about 25%, of organic surfactant.

The compositions may also be supplemented with other conventional laundry detergent components such as detergent builders and others.

Suitable synthetic anionic surfactants are water-soluble salts of C₈-C₂₂-alkylbenzenesulfonates, C₈-C₂₂₂-alkyl sulfates, C₁₀-C₁₀-alkylpolyethoxyethersulfates, C₈-C₂₄-paraffinsulfonates, alpha-C₁₂₋₂₄-olefinsulfonates, alpha-sulfonated C₆-C₂₀-fatty acids and their esters, C₁₀-C₁₀-alkylglyceryl ethersulfonates, fatty acid monoglyceride sulfates and sulfonates, especially those prepared from coconut oil, C₈-C₁₂-alkylphenolpolyethoxyethersulfates, 2-acyloxy-C�9-C₂₃-alkane-1-sulfonate and beta-alkyloxy-C₈-C₂�0-alkanesulfonates.

A particularly suitable class of anionic surfactants comprises water-soluble salts, especially the alkali metal, ammonium and alkanolammonium salts of organic sulfuric acid reaction products containing in their molecular structure an alkyl or alkaryl group having from about 8 to about 22, especially from about 10 to about 20 carbon atoms, and a sulfonic acid or sulfuric acid ester group. (The term "alkyl" includes the alkyl portion of acyl groups.) Examples of this group of synthetic detergents are the sodium and potassium alkyl sulfates, especially those obtained by sulfating the higher alcohols (C8-C18) which are produced by reducing the glycerides of tallow or coconut oil, and sodium and potassium alkylbenzenesulfonates in which the alkyl group contains from about 9 to about 15, especially from about 11 to about 13, carbon atoms in straight chain or branched chain configuration, e.g. B. those of the type described in US-A-2,220,099 and in US-A-2,477,383, and those prepared from alkylbenzenes, the latter obtained by alkylation with straight-chain chloroparaffins (using aluminum trichloride catalysis) or straight-chain olefins (using hydrogen fluoride catalysis). Particularly valuable are linear straight-chain alkylbenzenesulfonates in which the average alkyl group is 11.8 carbon atoms, abbreviated C11.8LAS, and methyl-branched C12-C15 alkyl sulfates.

The alkane chains of the above anionic non-soap surfactants may be derived from natural sources such as coconut oil or tallow, or may be synthetic, for example, using the Ziegler or Oxo process. Water solubility can be achieved by using alkali metal, ammonium or alkanolammonium cations; sodium is preferred.

Suitable fatty acid soaps can be selected from the common alkali metal (sodium, potassium), ammonium and alkylol ammonium salts of higher fatty acids containing from about 8 to about 24, preferably from about 10 to about 22, and most preferably from about 16 to about 22 carbon atoms in the alkyl chain. Fatty acids in partially hydrogenated form are also suitable for use herein, particularly in liquid compositions. Sodium and potassium soaps can be obtained by direct saponification of the fats and oils or by the neutralization of the free fatty acids prepared in a separate manufacturing process. Particularly useful are the sodium and potassium salts of mixtures of fatty acids derived from tallow and hydrogenated fish oil.

Mixtures of anionic surfactants are particularly suitable herein, especially mixtures of sulfonate and sulfate surfactants in a weight ratio of about 5:1 to about 1:5, preferably from about 5:1 to about 1:1, more preferably from about 5:1 to about 1.5:1. Particularly preferred is a mixture of an alkylbenzenesulfonate having 9 to 15, especially 11 to 13 carbon atoms in the alkyl radical, the cation being an alkali metal, preferably sodium; and either an alkyl sulfate having 10 to 20, preferably 12 to 18 carbon atoms in the alkyl radical or an ethoxy sulfate having 10 to 20, preferably 10 to 16 carbon atoms in the alkyl radical and an average degree of ethoxylation of 1 to 6, which has an alkali metal cation, preferably sodium.

The nonionic surfactants useful in the present invention are condensates of ethylene oxide with a hydrophobic moiety to provide a surfactant having an average hydrophilic-lipophilic balance (HLB) in the range of from about 8 to about 17, preferably from about 9.5 to 13.5, and more preferably from about 10 to about 12.5.

Examples of suitable non-ionic surfactants Compositions comprise the condensation products of primary or secondary aliphatic alcohols having from 8 to 24 carbon atoms in either straight chain or branched chain configuration, with from 2 to about 40, preferably from 2 to about 9, moles of ethylene oxide per mole of alcohol. Preferably, the aliphatic alcohol contains from 9 to 18 carbon atoms and is ethoxylated with from 2 to 9, desirably from 3 to 8, moles of ethylene oxide per mole of aliphatic alcohol. The preferred surfactants are prepared from primary alcohols which are either linear (such as those derived from natural fats or those prepared from ethylene by the Ziegler process, e.g. myristyl, cetyl, stearyl alcohols), or partially branched, such as the Lutensole (registered trademark), Dobanole (registered trademark) and Neodole (registered trademark) which have about 25% 2-methyl branching (Lutensol (registered trademark) is a trade name of BASF, Dobanol (registered trademark) and Neodol (registered trademark) are trade names of Shell), or Synperonics (registered trademark) which are said to have about 50% 2-methyl branching (Synperonic (registered trademark) is a trade name of ICI), or the primary alcohols which have more than 50% branched chain structure and are sold under the trade name Lial (registered trademark) sold by Liquichimica. Specific examples of nonionic surfactants falling within the scope of the invention include Dobanol (registered trademark) 45-4, Dobanol (registered trademark) 45-7, Dobanol (registered trademark) 45-9, Dobanol (registered trademark) 91-2.5, Dobanol (registered trademark) 91-3, Dobanol (registered trademark)

91-4, Dobanol (registered trademark) 91-6, Dobanol (registered trademark) 91-8, Dobanol (registered trademark) 23-6.5, Synperonic (registered trademark) 6, Synperonic (registered trademark) 14, the condensation products of coconut alcohol with an average of 5 to 12 moles of ethylene oxide per mole of alcohol, the coconut alkyl moiety having 10 to 14 carbon atoms, and the condensation products of tallow alcohol with an average of 7 to 12 moles of ethylene oxide per mole of alcohol, the Tallow portion contains essentially 16 to 22 carbon atoms. Secondary linear alkyl ethoxylates are also suitable in the present compositions, particularly those ethoxylates of the Tergitol (Registered Trade Mark) series having about 9 to 15 carbon atoms in the alkyl group and up to about 11, particularly about 3 to 9, ethoxy radicals per molecule.

Other suitable nonionic surfactants include the condensation products of C6-C12 alkylphenols with about 3 to 30, preferably 5 to 14, moles of ethylene oxide and the compounds formed by the condensation of ethylene oxide with a hydrophobic base obtained by the condensation of propylene oxide with propylene glycol, which synthetic nonionic detergents are commercially available under the trade name "Pluronic" (registered trademark) supplied by Wyandotte Chemicals Corporation.

Particularly preferred nonionic surfactants for use herein are the C9-C15 primary alcohol ethoxylates containing from 3 to 8 moles of ethylene oxide per mole of alcohol, especially the C12-C15 primary alcohols containing from 6 to 8 moles of ethylene oxide per mole of alcohol.

The compositions of the invention may also comprise from about 0.1% to about 20%, more preferably from about 0.5% to about 15%, especially from about 1% to about 5% of a water-soluble quaternary ammonium surfactant. Preferred for use herein are quaternary ammonium surfactants of the general formula

[R²(OR³)y][R⁴(OR³)y]₂R⁵N⁺X⁻

wherein R² is an alkyl, alkenyl or alkylbenzyl group having from about 8 to about 18 carbon atoms, preferably 10 to 14 carbon atoms in the alkyl chain; each R³ is selected from -CH₂CH₂-, -CH₂CH(CH₃)-, -CH₂CH(CH₂OH)-, -CH₂CH₂CH-, and mixtures thereof; each R³ is selected from C₁-C₄ alkyl, C₁-C₄ hydroxyalkyl, benzyl, ring structures formed by joining the two R⁴ groups, -CH₂CHOHCHOHCOR⁶CHOHCH₂OH, wherein R⁶ is is any hexose or hexose polymer having a molecular weight of less than about 1,000, and is hydrogen when y is not 0; R⁵ has the same meaning such as R4 or represents an alkyl chain wherein the total number of carbon atoms of R2 and R5 is no more than about 18; each y is from 0 to about 10 and the sum of the y values is from 0 to about 15; and X represents any compatible anion.

Preferred of the above are the alkyl quaternary ammonium surfactants, particularly the long chain monoalkyl surfactants described in the above formula when R5 is selected from the same groups as R4. The most preferred quaternary ammonium surfactants are the chloride, bromide and methyl sulfate alkyltrimethylammonium salts, alkyldi(hydroxyethyl)methylammonium salts, alkylhydroxyethyldimethylammonium salts and alkyloxypropyltrimethylammonium salts, where alkyl is C8-C16, preferably C10-C14. Of the above, decyltrimethylammonium methylsulfate, lauryltrimethylammonium chloride, myristyltrimethylammonium bromide and coconut trimethylammonium chloride and methylsulfate are particularly preferred.

Other useful cationic surfactants are described in US-A-4,259,217.

Highly preferred water-soluble cationic surfactants herein have a critical micelle concentration (CMC), as determined by, for example, surface tension or conductivity, of at least 200 ppm, preferably at least 500 ppm at 30ºC and in distilled water - see, for example, Critical Micelle Concentrations of Aqueous Surfactant Systems, P. Mukerjee and K.J. Mysels NSRDS-NBS 36 (1971).

Suitable builder salts useful in the compositions of the invention can be those of the polyvalent inorganic and polyvalent organic types or mixtures thereof. The amount of these materials is generally from about 15% to about 90%, preferably from about 20% to about 60% by weight of the total laundry composition. Non-limiting examples of suitable water-soluble, inorganic alkaline builder salts include the alkali metal carbonates, borates, phosphates, -pyrophosphates, -tripolyphosphates and -bicarbonates.

Organic builders/chelators which may be incorporated include organic polycarboxylates and aminopolycarboxylates and their salts, organic phosphonate derivatives such as those described in US-A-3,213,030, US-A-3,433,021, US-A-3,292,121 and US-A-2,599,807, and carboxylic acid builder salts such as those contained in US-A-3,308,067. Carboxylates particularly useful for use in liquid detergents are the C₁₀-C₂₀, preferably C₁₂-C₁₆ alkyl or alkenyl succinates, such as lauryl, myristyl, palmityl, 2-dodecenyl and 2-pentadecenyl succinate.

Preferred chelating agents include citric acid, nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEEDTA), nitrilo(trimethylenephosphonic acid) (NTMP), ethylenediaminetetra(methylenephosphonic acid) (EDTMP) and diethylenetriaminepenta(methylenephosphonic acid) (DETPMP) and salts thereof. Mixtures of organic and/or inorganic builders can be used herein. One such mixture of builders is described in CA-A-755 038, e.g. a ternary mixture of sodium tripolyphosphate, trisodium nitrilotriacetate and trisodium ethane-1-hydroxy-1,1-diphosphonate.

Detergent compositions useful herein may have a low phosphate content or a zero phosphate content, corresponding to a phosphorus content of less than about 5% by weight, preferably less than about 2% by weight. In compositions of this type, the builder is preferably of the aluminosilicate type which is effective by cation exchange to remove multivalent mineral hardness and heavy metal ions from solution. A preferred builder of this type has the formula Naz(AlO₂)z(SiO₂)y·xH₂O, where z and y are integers of at least 6, the molar ratio of z to y is in the range of 1.0 to about 0.5, and x is an integer of about 15 to about 264. Compositions containing builder salts of this type are the subject of GB-A-1 429 143, DE-A-2 433 485 and DE-A-2 525 778.

The detergent compositions herein may be used by all types of detergent and laundry washing components.

An alkali metal or alkaline earth metal silicate may also be present. The alkali metal silicate preferably represents from about 1% to about 20%, more preferably from about 3% to about 15%, by weight of the total composition. Suitable silicate solids have a molar ratio of SiO2/alkali metal2O in the range of from about 0.5 to about 3.3, although silicates in which the ratio is at least 2.7:1, especially at least about 3:1, are highly preferred from the standpoint of maintaining optimal stability of the antioxidant. In these embodiments, the silicate is further preferably obtained from a source of fumed silica. The value of the high ratio combination of silicates with PVP to maintain antioxidant stability and reduce or prevent its oxidative and chemical degradation has apparently not been recognized to date and represents another important aspect of the present invention.

The detergent compositions of the present invention also contain bleaching components. Generally, suitable bleaching agents are inorganic peroxygen bleaching agents selected from inorganic peroxy salts, hydrogen peroxide and hydrogen peroxide adducts. However, the compositions herein may also be supplemented with organic peroxyacids and salts thereof. Suitable inorganic peroxygen bleaching agents include sodium perborate mono- and tetrahydrate, sodium percarbonate, sodium persilicate, urea-hydrogen peroxide addition products and the clathrate 4Na₂SO₄:2H₂O₂:1NaCl. Suitable organic bleaching agents include peroxylauric acid, peroxyoctanoic acid, peroxynonanoic acid, peroxydecanoic acid, diperoxydodecanedioic acid, diperoxyazelaic acid, mono- and diperoxyphthalic acid and mono- and diperoxyisophthalic acid and salts (especially the magnesium salts) thereof. The bleaching agent is present in an amount of from 0.5% to 40%, preferably from 5% to 20% by weight of the total detergent composition.

Other optional components of the compositions herein include suds suppressors, enzymes, fluorescent agents, photoactivators, soil suspending agents, flow aids, pigments, perfumes, fabric conditioning agents and others.

Foam suppressors are represented by materials of the type of silicones, waxes, vegetable and hydrocarbon oils, and phosphate esters. Suitable silicone-based foam suppressors include polydimethylsiloxanes having a molecular weight in the range of about 200 to about 200,000 and a kinematic viscosity in the range of about 20 to about 2,000,000 mm²/s, preferably from about 3000 to about 30,000 min²/s, and mixtures of siloxanes and hydrophobic, silanized (preferably trimethylsilanized) silica having a particle size in the range of about 10 millimicrons to about 20 millimicrons and a specific surface area of greater than about 50 m²/g. Suitable waxes include microcrystalline waxes having a melting point in the range of about 65°C to about 100°C, a molecular weight in the range of about 4,000 to 10,000, and a penetration value of at least 6 as measured at 77°C according to ASTM-D1321, and also paraffin waxes, synthetic waxes, and natural waxes. Suitable phosphate esters include mono- and/or di-C16-C22-alkyl or alkenyl phosphate esters, and the corresponding mono- and/or dialkyl or alkenyl ether phosphates containing up to 6 ethoxy groups per molecule.

Enzymes suitable for use herein include those described in US-A-3,519,570 and US-A-3,533,139. In liquid detergents, enzyme stabilizers such as propanediol, sodium formate, calcium and boric acid are also useful. Suitable fluorescent agents include Blankophor (registered Trademark) MBBH (Bayer AG) and Tinopal (Registered Trademark) CBS-X and EMS (Ciba Geigy). Photoactivators are described in EP-A-57088, highly preferred materials being zinc phthalocyanine tri- and tetrasulfonates. Suitable fabric conditioning agents include smectite type clays as described in GB-A-1 400 898 and di-C 12 -C 24 alkyl or alkenyl amines and ammonium salts.

Antiredeposition and soil suspending agents useful herein include the ethoxylated amine, imine and ammonium compounds described in EP-A-0 112 593, EP-A-0 111 965, EP-A-0 111 984, EP-A-0 111 976 and EP-A-0 112 592, as well as cellulose derivatives such as methylcellulose, carboxymethylcellulose and hydroxyethylcellulose, and homo- or copolymeric polycarboxylic acids or salts thereof wherein the polycarboxylic acid has at least two carboxyl radicals separated from each other by not more than two carbon atoms. Polymers of this type are described in GB-A-1 596 756. Preferred polymers include copolymers or salts thereof of maleic anhydride with ethylene, methyl vinyl ether, acrylic acid or methacrylic acid, wherein the maleic anhydride constitutes at least about 10 mole percent, preferably at least about 20 mole percent of the copolymer. These polymers are valuable for improving whiteness maintenance, fabric ash deposition and cleaning performance against clay soils.

The laundry detergent and additive compositions of the invention can be formulated, packaged and retailed in conventional granular, powdered or liquid form, or the composition can be formulated as part of a laundry product comprising the composition in water-releasable combination with a water-insoluble substrate or a single or multiple compartment sachet.

Preferred laundry products for use herein comprise a substrate or sachet formed from a flexible, water-insoluble sheet-like material. The sheet-like material may be made from paper, woven or nonwoven fabrics, or the like.

The basis weight of the water-insoluble sheet is preferably from about 10 to about 70 g/m², more preferably from about 20 to about 50 g/m². Preferred materials for use herein are apertured nonwovens, which are generally defined as adhesively or heat-bonded fibrous or filamentary products having a web structure or a carded fiber structure (where the fiber strength is sufficient to permit carding), or comprising fibrous mats wherein the fibers or filaments are distributed randomly or in a statistical arrangement (i.e., in an arrangement of fibers in a carded web wherein there is often both partial orientation of the fibers and completely random statistical orientation) or substantially aligned. The fibres or filaments may be of natural origin (e.g. wool, silk, wood pulp, jute, hemp, cotton, linen, sisal or ramie), of synthetic origin (e.g. rayon, cellulose esters, polyvinyl derivatives, polyolefins, polyamides or polyesters) or mixtures of any of the above.

In general, the nonwoven webs can be made by air or water laying processes in which the fibers or filaments are first cut from long strands into the desired lengths, passed into a stream of water or air, and then deposited on a screen through which the fiber-laden air or water is passed. The deposited fibers or filaments are then bonded together by adhesive or heat, dried, cured, and otherwise treated as desired to form the nonwoven web. However, nonwoven webs made from spunbonded, spunlaced, or meltblown nonwovens are also suitable.

Preferably, the nonwoven fabric is made from cellulosic fibers, particularly regenerated cellulose or rayon, which are provided with standard fabric additives such as sodium oleate. The nonwoven fabric also preferably contains a polyolefin such as polypropylene to enable heat sealing to the poly(ethylene oxide) film. Preferably, the fibers have a length of from about 4 to about 50 mm, particularly from about 8 mm to about 20 mm, and have about 1.1 up to 5.5 dtex (about 1 to about 5 denier) (denier is an internationally recognized unit of yarn size, which corresponds to the weight of 9,000 grams of yarn).

Preferably, the fibers are at least partially randomly oriented, more preferably substantially randomly oriented, and are adhesively bonded to one another by means of a hydrophobic or substantially hydrophobic binder resin, more preferably a nonionic, self-crosslinking acrylic polymer or polymers. In highly preferred embodiments, the cloth comprises from about 75% to about 88%, more preferably from about 78% to about 84%, by weight of fibers and from about 12% to about 25%, more preferably from about 16% to about 22%, by weight of hydrophobic binder resin polymer and has a basis weight of from about 10 to about 70, preferably 20 to 50 g/m². Suitable hydrophobic binder resins are ethyl acrylate resins such as Primal (registered trademark) HA24, Rhoplex (registered trademark) HA8 and HA16 (Rohm and Haas, Inc.) and mixtures thereof.

The substrate apertures, which extend between the opposing surfaces of the substrate, are typically arranged in a pattern and are formed during the laying down of the fibers to make the substrate. Exemplary apertured nonwoven substrates are described in US-A-3,741,724, US-A-3,930,086 and US-A-3,750,237.

An example of an apertured nonwoven substrate useful herein is a polypropylene-containing sheet of regenerated cellulose fibers having 1.5 denier fibers bonded together with Rhoplex HA 8 binder (fiber to binder ratio is about 77:23) having a basis weight of about 35 g/m² and about 17 apertures/cm². The apertures are generally elliptical in shape and arranged side by side. The apertures have a width of about 0.9 mm and a length of about 2.5 mm, measured in a relaxed state. Another highly preferred substrate is comprised of 1.5 denier regenerated cellulose fibers and Rhoplex HA 8 binder in a fiber to binder ratio of about 82:18 with a basis weight of about 35 g/m² and about 22 openings/cm². In this example, the openings are generally square shaped, with a width of about 1.1 min. The openings are again arranged next to each other.

In the substrate embodiments of the invention, the substrate is coated or impregnated with the laundry composition in a composition to substrate weight ratio of at least about 3:1, preferably at least about 5:1. In these embodiments, the laundry composition preferably contains at least about 5%, more preferably at least about 15%, by weight of the composition of water-soluble or water-dispersible organic binder. Preferably, the binder is selected from polyethylene glycols having a molecular weight of greater than about 1,000, more preferably greater than about 4,000, C12-C18 fatty acids and esters and amides thereof, polyvinylpyrrolidone having a molecular weight in a range of about 40,000 to about 700,000, and C14-C24 fatty alcohols ethoxylated with about 14 to about 100 moles of ethylene oxide.

The laundry compositions of the invention in granular or powdered form are preferably prepared by spray drying an aqueous slurry comprising the anionic surfactant and the detergency builder to a density of at least about 0.3 g/cc, spraying on the nonionic surfactant, if present, optionally mixing the spray dried granules, for example in a Patterson-Kelley twin bowl mixer, to a bulk density of at least about 0.5 g/cc, and then mixing in the bleach activator composition in particulate form. The aqueous slurry for spray drying preferably comprises from about 30% to about 60% water and from about 40% to about 70% of the detergency builder; it is heated to a temperature of about 60°C to about 90°C and spray dried in an air stream having an inlet temperature of about 200°C to about 400°C, preferably about 275°C to about 350°C, and an outlet temperature of about 95°C to about 125°C, preferably about 100°C to about 115°C. The weight average particle size of the spray dried Granule size is from about 0.15 to about 3 mm, preferably from about 0.5 mm to about 1.4 mm. After mixing, the weight average particle size is from about 0.1 to about 0.5 mm, preferably from about 0.15 to about 0.4 mm.

In the examples, the abbreviations used have the following meaning:

LAS : linear sodium C₁₂-alkylbenzenesulfonate

TAS : Sodium tallow alkyl sulfate

C14/15AS : Sodium C₁₄-C₁₅-alkyl sulfate

TAEn : hydrogenated tallow alcohol, ethoxylated with n moles of ethylene oxide per mole of alcohol

C₁₄TMAB : C₁₄-alkyltrimethylaminonium bromide

Dobanol (registered trademark) 45-E-7 : a C₁₄-C₁₅ primary alcohol condensed with 7 moles of ethylene oxide, sold by Shell

INOBS : Sodium 3,5,5-trimethylhexanoyloxybenzenesulfonate

TAED : Tetraacetylethylenediamine

Silicone/silicon dioxide: mixture of polydimethylsiloxane and silanized silicon dioxide in the ratio 85:15, prilled with STPP and TAE₈₀

Enzyme : Savinase prills

NTA : Sodium nitrilotriacetate

PVP : Polyvinylpyrrolidone with a molecular weight of 9,200

STPP : Sodium tripolyphosphate

Zeolite : Zeolite 4A

Gantrez (registered trademark) AN 119 : Maleic anhydride/vinyl methyl ether copolymer, MW approximately 240,000

Na₂CO₃ : Sodium

Silicate : sodium silicate (SiO₂: Na₂O = 3.2 : 1)

MA/AA : Maleic acid/acrylic acid copolymer, molar ratio 1:3, MW 70,000

EDTA : Sodium ethylenediaminetetraacetate

Brightener : Tinopal (registered trademark) CBS-X

EDTMP : Ethylenediaminetetra(methylenephosphonic acid), sold by Monsanto under the trade name Dequest (registered trademark) 2041

DETPMP : Diethylenetriaminepenta(methylenephosphonic acid)

EXAMPLES I TO V

Granular detergent compositions are prepared as follows. A detergent base powder composition is first prepared by mixing the listed components in a crutcher as an aqueous slurry at a temperature of about 55°C and containing about 35% water. The slurry is then spray dried at a gas inlet temperature of about 330°C to form base powder granules and the granules are mixed in a Patterson-Kelley twin bowl mixer. The antioxidant is then incorporated into the glassy PVP carrier by intimately mixing antioxidant and PVP at a weight ratio (PVP:antioxidant) of about 60:40, heating the mixture to about 120°C to melt the antioxidant, cooling the mixture to room temperature and grinding to a weight average particle size of about 0.2-1 min. A separate bleach activator composition is then prepared by agglomerating the listed components in a mixer-agglomerator (Examples I to V). Finally, the detergent base powder composition is dry blended with enzyme, silicate, carbonate, bleach and bleach activator and, if present, additional nonionic surfactant is sprayed onto the total mixture.

All percentages are by weight of the total detergent composition. EXAMPLES Detergent Base Powder Gantrez (Registered Trademark) AN119 Silicate Zeolite Brightener Sodium Tripolyphosphate Magnesium Sulphate (ppm) Sodium Sulphate, Moisture and Miscellaneous Bleach Activator Composition Disodium Dihydrogen Pyrophosphate Sodium Sulphate Zeolite Fatty Acids EXAMPLES (cont.) OTHER ADDITIVES Enzyme Sodium Perborate Tetrahydrate Sodium Perborate Monohydrate Dobanol (Registered Trademark) 45-E-7 Silicate Sodium Carbonate

The above products combine exceptional bleaching performance, substrate safety, water dispersibility, granularity and detergent performance across the range of wash temperatures and soil types.

The examples are repeated, whereby the antioxidant is replaced by:

2,2'-methylenebis(4-methyl-6-tert.butylphenol),

4,4'-methylenebis(2,6-di-tert.butylphenol),

2,2'-methylenebis(4-methyl-6-(1-methylcyclohexyl)phenol),

4,4'-Thiobis(6-tert.butyl-3-methylphenol),

4,4'-Butylidene-bis(6-tert.butyl-3-methylphenol),

6-tert.butylhydroquinone, pyrogallol,

2,2'-methylene-bis(4-methyl-6-nonylphenol),

2,2'-Iso-nonylene-bis(2,4-dimethylphenol),

Octadecyl 3-(3,5-di-tert.butyl-4-hydroxyphenyl)propionate,

Tetrakis[methylene-3-(3',5'-di-tert.butyl-4'-hydroxyphenylpropionate)methane, the compounds of formula II, wherein R and R₁ are tert.butyl and R₂ is selected from CH₂SCH₂CO₂H, CH₂ CH₂CO₂H and the C₁₈-alkyl esters thereof,

Tris-(2-methyl-4-hydroxy-5-tert.butylphenyl)butane, the compound of formula IV, wherein R is tert.butyl, R₁ is 4-methyl, R₅ is dicyclopentadienediyl and m is on average about 1, 2,4-bis(n-octylthio)-6-(4-hydroxy-3,5-di-tert.butylanilino)-1,3,5-triazine,

2-(2'-Hydroxy-3'-butyl-5'-methylphenyl)-5-chlorobenzotriazole,

Tri(4-methyl-2,6-di-tert.butylphenyl) metaborate,

Tri(4-methyl-2,6-di-tert.butylphenyl)orthoborate,

2,6-Di-tert.butylphenyl-di-isopropylorthoborate,

4-Methyl-2,6-tert.dibutylphenyl-di-isopropylorthoborate,

Di-(4-methyl-2,6-di-tert.butylphenyl)-n-butylorthoborate,

Di-(2,6-tert.butylphenyl)-n-butylorthoborate and

4-Methyl-2,6-di-tert.butylphenyl-di-n-butylorthoborate.

Once again, improved performance is achieved.

The examples are repeated and the resulting products are incorporated into two-chamber bags, which are prepared as follows.

The sachets are made from a nonwoven fabric consisting of 100% unbleached crimped rayon fibers of 1.65 dtex (1.5 denier) bonded with 18% polyacrylate binder, which nonwoven fabric has a basis weight of 35 g/m². The sachet is made from a sheet of fabric measuring 120 min x 80 min by folding it in half along the lengthwise direction, sealing along the two opposite free edges with sodium silicate solution and along a longitudinal seam running parallel to and midway between the two opposite edges, filling the two compartments with 120 ml of the detergent composition each and then sealing along the open edge of the sachet.

When used as laundry detergent products for the main wash cycle, the above examples again ensure excellent bleach activator stability and substrate safety, excellent water dispersibility and detergent performance over the range of wash temperatures and soil types.

Claims (18)

1. A detergent composition comprising (a) 1% to 75% by weight of organic surfactant selected from anionic, nonionic, cationic, ampholytic and zwitterionic surfactants and mixtures thereof, (b) a peroxygen bleach component comprising i) 0.5% to 40% by weight of peroxygen bleach and ii) 0.1% to 25% by weight of peroxyacid bleach precursor, and (c) 0.01% to 2% by weight of an antioxidant, which antioxidant is incorporated in a solid, amorphous, glassy carrier material made of polyvinylpyrrolidone (PVP), the weight ratio of antioxidant:PVP being in the range of 5:1 to 1:10. 2. A composition according to claim 1, wherein the antioxidant is a phenolic antioxidant or a phenol ester antioxidant. 3. Composition according to claim 2, wherein the antioxidant has the general formula II: wherein R is selected from H, OH, C₁-C₁₈ alkyl and alkenyl, C₅-C₈ cycloalkyl, aryl, aralkyl, araloxyalkyl or arylthioalkyl, each radical having up to 4 carbon atoms in the alkyl radical, which cycloalkyl and aryl radicals are unsubstituted or substituted by one or more identical or different substituents selected from C₁-C₄ alkyl and alkoxy groups; R₁ is selected from H, OH, C₁-C₁₈ alkyl and benzotriazole and aminotriazine derivatives; and R₂ is selected from H, OH, CO₂H or salts or esters thereof, benzotriazole and aminotriazine derivatives, C₁-C₁₈alkyl and -alkenyl, C₁-C₄alkylthio and C₁-C₄alkylthio-(C₁-C₄)alkylene, OH and C₁-C₁₄alkyloxy, which alkyl or alkenyl radicals are substituted or unsubstituted by one or more C₁-C₄alkoxy radicals or by one or more carboxylic acid or phosphonic acid radicals or salts or esters thereof, with the proviso that when R and R₁ both represent H, R₂ stands for OH or a C₁-C₄-alkyloxy radical. 4. A composition according to claim 3, wherein R is selected from methyl, ethyl, isopropyl, sec-butyl, tert-butyl, tert-amyl, 1,1,3,3-tetramethylbutyl, α,α-dimethylbenzyl, cyclohexyl and 1-methylcyclohexyl, R₁ is selected from H, methyl, ethyl, isopropyl, sec-butyl and tert-butyl; and R₂ is is selected from OH, methyl, ethyl, isopropyl, sec-butyl, tert-butyl, tert-amyl, 1,1,3,3-tetramethylbutyl, α,α-dimethylbenzyl, -CH₂CO₂M, -CH₂CH₂CO₂M, -CH₂SCH₂CO₂M and -CH₂SCH₂CH₂CO₂M, wherein M is selected from H, alkali metal and alkaline earth metal and ammonium cations and C₁₋₁₈ alkyl and alkenyl ester radicals. 5. Composition according to claim 2, wherein the antioxidant has the general formula III wherein each R is independently selected from H, OH, C₁-C₁₈ alkyl and alkenyl, C₅-C₈ cycloalkyl, aryl, aralkyl, araloxyalkyl or arylthioalkyl, each having up to 4 carbon atoms in the alkyl group, which cycloalkyl and aryl groups are substituted or unsubstituted by one or more identical or different substituents selected from C₁-C₄ alkyl and alkoxy groups; each R₁ is independently selected from OH or ortho- or para-substituted C₁-C₁₈ alkyl; each R₄ is independently selected from ortho- and para-substituted C1-C4 alkylene, C1-C4 alkyleneoxy-(C1-C4)alkylene and C1-C4 alkylenethio-(C1-C4)alkylene radicals, which C1-C4 alkylene radicals are optionally substituted with one or more C1-C4 alkyleneoxycarbonyl or mono- or di-(C1-C4 alkyleneoxy)phosphonyl radicals, or wherein R4 represents a direct bond; n is from 2 to 4; and wherein B is a di-, tri- or tetravalent bridging radical. 6. Composition according to claim 2, wherein the antioxidant is a complete or partial ester of a boric acid selected from orthoboric acid (H₃BO₃), metaboric acid (HBO₃), pyroboric acid (H₄B₂O₅), boronic acid (H₃BO₂) and borinic acid (H₃BO), wherein at least one esterifying group is a phenol having the general formula II or III. 7. Composition according to claim 6, wherein at least one esterifying group is a phenol having the general formula II, wherein R and R₁ are selected from C₄-C₁₀ tert.alkyl radicals branched at the alpha carbon and R₂ is selected from H and C₁-C₄ alkyl radicals. 8. Composition according to claim 2, wherein the antioxidant is an oligomer of the general formula IV wherein each R is independently selected from H, OH, C₁-C₁₈ alkyl and alkenyl, C₅-C₈ cycloalkyl, aryl, aralkyl, araloxyalkyl or arylthioalkyl, each having up to 4 carbon atoms in the alkyl group, which cycloalkyl and aryl groups are unsubstituted or substituted by one or more identical or different substituents selected from C₁-C₄ alkyl and alkoxy groups; each R₁ is independently selected from OH or ortho- or para-substituted C₁-C₁₈ alkyl; R₅ is selected from C₂-C₁₀ alkylene and cycloalkylene groups; and represents a numerical average from 1 to 10. 9. A composition according to claim 8, wherein R is tert-butyl, R₁ is 4-methyl, R₅ is dicyclopentadienediyl and m is an average of from 1 to 3. 10. The composition of claim 1, wherein the antioxidant is a hindered amine type light stabilizer. 11. A composition according to claim 10, wherein the hindered amine type light stabilizer is a 2,2,6,6-tetramethylpiperidine derivative or a 1,2-dihydro-2,2,4-trimethylquinoline derivative. 12. Composition according to one of claims 1 to 11, wherein the peroxyacid bleach precursor is a compound of the general formula I Ac - L I wherein Ac represents the acyl radical of an organic carboxylic acid which comprises an optionally substituted, linear or branched C6-C20 alkyl or alkenyl radical or a C6-C20 alkyl-substituted aryl radical and L represents a leaving group whose conjugate acid has a pKa value in the range of 4 to 13. 13. Composition according to claim 12, wherein in formula I Ac the Formula R₅CO- wherein R₅ is a linear or branched alkyl group having from 6 to 20, preferably 6 to 12, more preferably 7 to 9, carbon atoms, and wherein the longest linear alkyl chain extending therefrom and including the carbonyl carbon contains from 5 to 18, preferably 5 to 10 carbon atoms, wherein R₅ is optionally substituted by Cl, Br, OCH₃ or OC₂H₅. 14. Composition according to claim 12, wherein in formula I Ac has the formula R₅(AO)mXA, wherein R₅ is a linear or branched alkyl or alkylaryl group having 6 to 20, preferably 6 to 15 carbon atoms in the alkyl radical, where R₅ is optionally substituted by Cl, Br, OCH₃ or OC₂H₅, AO is oxyethylene or oxypropylene, m is from 0 to 100, X is O, NR or CO-NR₁, and A is CO, CO-CO, R₆-CO, CO-R₆-CO or CO-NR₁-R₆-CO, wherein R₁ is C₁-C₄alkyl and R₆ is C₁-C₄alkyl. Alkylene, alkenylene, arylene or alkarylene with 1 to 8 carbon atoms in the alkylene or alkenylene radical. 15. A composition according to any one of claims 1 to 11, wherein the peroxyacid bleach precursor comprises a peracetic acid bleach precursor, in particular tetraacetylethylenediamine, tetraacetylmethylenediamine, tetraacetylhexylenediamine, sodium p-acetoxybenzenesulfonate, tetraacetylglycouril, pentaacetylglucose, octaacetylglucose or methyl o-acetoxybenzoate. 16. Composition according to one of claims 1 to 11, wherein the peroxyacid bleach precursor is a mixture of a peracetic acid bleach precursor and a compound of the general formula I Ac - L I wherein Ac represents the acyl radical of an organic carboxylic acid which comprises an optionally substituted, linear or branched C6-C20 alkyl or alkenyl radical or a C6-C20 alkyl-substituted aryl radical and L represents a leaving group whose conjugate acid has a pKa value in the range of 4 to 13. 17. A composition according to any one of claims 1 to 16, which additionally comprises 1% to 20%, preferably 3% to 15% of an alkali metal silicate having a SiO₂/alkali metal₂O ratio of at least 2.7, preferably at least 3.1. 18. A composition according to claim 17, wherein the alkali metal silicate is obtained from fumed silica.