Field of the Invention

The present invention relates to a solid laundry composition, particularly to a solid laundry detergent composition having good biodegradability.

Background of the Invention

From a consumer perspective, greying, dinginess and yellowing of fabrics are concerns that needs to be addressed. One of the reasons for greying or yellowing of the fabric is due to soil redeposition. To reduce the redeposition of soil, polycarboxylate polymers have been included in detergent composition to act as antiredeposition agents.

A copolymer of acrylic and maleic acid is a well-known antiredeposition agent used in a solid laundry detergent composition. Copolymers of acrylic acid and maleic acid are also known to act as a structurant in a solid laundry detergent composition, particularly in a spray-dried detergent particle. However, a disadvantage of adding polycarboxylate polymer in the detergent composition is that these polymers are not easily biodegradable.

Yet another factor which is of a concern in a solid laundry detergent composition, is the problem of ashing on laundered fabrics. The deposition onto the laundered fabrics of the insoluble ingredients added to the detergent composition and the insoluble precipitates formed by the building of hard water is commonly termed as ashing. Ashing negatively impacts the look and feel of the laundering fabrics which appears duller and has a rough feel upon touch. Calcium ions in hard water precipitates in presence of carbonates and silicates in the detergent composition and the precipitated calcium carbonate tends to deposit on the fabrics. The continued deposition of calcium carbonate over multiple washes renders a rough feel to the white fabrics and coloured fabrics tend to look duller. Maintaining the brightness of the coloured fabrics and softness of the fabrics over multiple wash cycles remains to be an unmet need for consumers.

One way to address this is to reduce or totally remove the insoluble ingredients present in the detergent composition. The insoluble in the detergent composition includes ingredients such as zeolites, carbonate, sulphates, and silicates of alkaline earth metal. These insoluble ingredients act as carriers for liquid ingredients and/or act as layering agents to provide free- flowing powders. Hence partial or complete removal of these insoluble ingredients may impact powder properties and processability.

Another way to solve the problem of ashing is to reduce builders such as carbonate and silicates in the composition. However, a dichotomy exists in that any reduction or removal of the carbonate and silicates has a direct impact on the cleaning performance and powder properties of the solid detergent composition. Carbonate and silicates builders in the solid laundry composition provide the detergent composition alkalinity which improves the cleaning performance. They also provide the solid detergent composition, particularly the spray-dried detergent particle good physical characteristics such as good cake strength and good flowability.

GB2095275 A (Kao Soap Co. Ltd., 1982) discloses a detergent composition which provides remarkable detersive effect particularly on inorganic dirt, the composition includes an alkali cellulase for enhancing the detersive performance of phosphorus-free detergents and detergent having only a low phosphorus content.

W02009/154934 A1 (Procter & Gamble Company) discloses a laundry composition having substituted polysaccharide and cellulase enzyme.

JP2003 105389 A (Lion Corp) discloses a detergent composition for control of bacteria on fabric to prevent malodour and discloses a detergent composition which includes 0.5 wt.% acrylic maleic acid copolymer (AA/MA ratio 70:30) and 0.2 wt.% cellulase enzyme.

WO 2011/109320 A1 (P&G) discloses a solid laundry detergent composition for providing good cleaning performance even at low temperature conditions and discloses a granular dry laundry detergent composition which includes 1.7 wt.% STPP, 0.3 wt.% sodium polyacrylate/maleate copolymer (70:30 ratio), 0.6 wt.% carboxymethylcellulose, 0.5 wt.% HEDP, 5 wt.% sodium percarbonate and 53ppm cellulase.

EP 2377914 A1 (P&G, 2011) discloses a solid fabric treatment detergent composition for providing good cold water cleaning performance and discloses a composition which includes 0.6 wt.% STPP, 0.3 wt.% sodium polyacrylate/maleate copolymer (70:30 ratio), 0.5 wt.% hydrophobically modified carboxymethylcellulose, 0.3 wt.% HEDP, 7 wt.% sodium percarbonate and 53ppm cellulase.

WO 99/13040 A1 (P&G) discloses a detergent composition for addressing the problem of bleach instability of sequestrants and providing improved encrustation sequestering and improved bleach performance. This document discloses a composition which includes 0.5 wt.% MA/AA (copolymer with 1 :4 maleic/acrylic acid), 1 wt.% sodium perborate bleach and 0.2 wt.% cellulase.

WO 00/42147 A1 (P&G) discloses a detergent composition which provides superior cleaning performance, and the disclosed composition includes 0.0014 wt.% cellulase, 0.5 wt.% CMC and 0.5 wt.% acrylic maleic acid copolymer (ratio of acrylic to maleic acid of 4:1)

JP 2007/070613 A (Kao) discloses a granular laundry detergent composition which provides excellent softness and prevents redeposition to the fibre products while washing. This document discloses a granular laundry composition which includes 0.1 wt.% cellulase, 0.5 wt.% CMC and 0.5 wt.% acrylic maleic acid copolymer.

As can be seen from the prior art documents there is still a need to provide a solid detergent composition having both good biodegradability and which provides good cleaning performance and good antiredeposition benefits while maintaining good powder properties and addressing ashing issues.

Thus, there remains a need for a solid laundry composition having good fabric cleaning performance, good biodegradability index, good whiteness maintenance and very good powder properties, good antiredeposition benefits while the solid laundry composition has low levels of alkaline builders.

It is thus an object of the present invention to provide a solid laundry composition which has good biodegradability.

It is another object of the present invention to provide a solid laundry composition which provides fabric care benefits while maintaining good cleaning performance and good antiredeposition benefits. It is yet another object of the present invention to provide a solid laundry composition which provide fabric care benefits by including reduced levels of bleach or no bleach while maintaining good cleaning performance.

It is yet another object of the present invention to provide a solid laundry composition which provides lower alkalinity wash liquor as compared to conventional laundry composition yet maintains good cleaning performance.

Summary of the Invention

The present inventors have surprisingly found that combining a biodegradable antiredeposition agent along with specific low levels of a copolymer of acrylic acid and maleic acid having specific weight ratio of acrylic acid and maleic acid provides for significantly reduce ashing on the laundered fabrics while delivering good antiredeposition benefits and improved cleaning performance. The solid laundry composition was also found to provide good biodegradability. The solid laundry composition was preferably found to provide good cleaning performance even at reduced levels or no bleach in the composition.

According to a first aspect of the present invention disclosed is a solid laundry composition comprising:

(i) a biodegradable antiredeposition agent;

(ii) 0.02 wt.% to 0.5 wt.% copolymer of acrylic acid and maleic acid. wherein the copolymer of acrylic acid and maleic acid has a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1 :1 to 1:9.

According to a second aspect of the present invention, disclosed is a method for laundering a textile surface with the solid laundry composition according to the first aspect of the present invention comprising the steps of: i) preparing an aqueous wash liquor by contacting the solid laundry composition according to the first aspect with a liquid; ii) soaking said textile surface in the wash liquor for a predetermined period of time; and, iii) optionally rinsing the textile surface.

According to a third aspect of the present invention disclosed is the use of a biodegradable antiredeposition agent and 0.02 wt.% to 0.5 wt.% acrylic maleic copolymer wherein the copolymer of acrylic acid and maleic acid has a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1 :1 to 1:9 in a solid laundry composition to provide improved cleaning performance.

According to yet another aspect of the present invention, disclosed is a use of a biodegradable antiredeposition agent and from 0.02 wt.% to 0.5 wt.% copolymer of acrylic acid and maleic acid wherein the copolymer of acrylic acid and maleic acid has a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1 :1 to 1:9 in a solid laundry composition for exhibiting improved biodegradability.

These and other aspects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed description and the appended claims. For the avoidance of doubt, any feature of one aspect of the present invention may be utilised in any other aspect of the invention. The word "comprising" is intended to mean "including" but not necessarily "consisting of" or "composed of." In other words, the listed steps or options need not be exhaustive. It is noted that the examples given in the description below are intended to clarify the invention and are not intended to limit the invention to those examples per se.

Similarly, all percentages are weight/weight percentages unless otherwise indicated. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word "about". Numerical ranges expressed in the format "from x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "from x to y", it is understood that all ranges combining the different endpoints are also contemplated.

Detailed Description of the Invention

According to a first aspect of the present invention, disclosed is a solid laundry detergent composition having a biodegradable antiredeposition agent and a copolymer of acrylic and maleic acid.

Biodegradable antiredeposition agent:

According to a first aspect of the present invention disclosed solid laundry detergent composition includes a biodegradable antiredeposition agent. The biodegradable antiredeposition agent is preferably selected from the group consisting of cellulase, substituted polysaccharide or mixtures thereof.

Cellulase:

The biodegradable antiredeposition agent is preferably a cellulase enzyme. The term cellulase refers to an enzyme that hydrolzes a cellulosic material. Such enzymes include those selected from endoglucanase (e.g., EC 3.2.1.4), cellobiohydrolase, beta-glucosidase, or combinations thereof. The cellulase may for example be a mono-component or a mixture of endo-1 ,4-beta- glucanase also referred to as endoglucanase.

Suitable cellulases include those from bacterial origin, fungal origin, or a combination thereof. Chemically modified or protein engineered mutants are also contemplated. Suitable cellulases include those from the genera Bacillus, Pseudomonas, Humicola, Myceliophthora, Fusarium, Thielavia, Trichoderma, and Acremonium. Exemplary cellulases include a fungal cellulase from Humicola insolens (US 4,435,307) or from Trichoderma, e.g., T. reesei or T. viride. Other suitable cellulases are from Thielavia e.g., Thielavia terrestris as described in WO 96/29397 or the fungal cellulases produced from Myceliophthora thermophila and Fusarium oxysporum disclosed in US 5,648,263, US 5,691 ,178, US 5,776,757, WO 89/09259 and WO 91/17244. Also relevant are cellulases from Bacillus as described in WO 02/099091 and JP 2000210081. Suitable cellulases are alkaline or neutral cellulases, preferably those having colour care benefits. Examples of cellulases are described in EP 0 495 257, EP 0 531 372, WO 96/11262, WO 96/29397, WO 98/08940. Other examples are cellulase variants such as those described in WO 94/07998, EP 05/531315, US 5,457,046, US 5,686,593, US 5,763,254, WO 95/24471 , WO 98/12307.

Other cellulases are endo-beta-1 ,4-glucanase enzyme having a sequence of at least 97% identity to the amino acid sequence of position 1 to position 773 of SEQ ID NO:2 of WO 2002/099091 or a family 44 xyloglucanase, which a xyloglucanase enzyme having a sequence of at least 60% identity to positions 40-559 of SEQ ID NO. 2 of WO 2001/062903.

Commercially available cellulases include Carezyme®, Carezyme® Premium, Celluzyme®, Celluclean®, Celluclast®, Endolase®, Renozyme®; Whitezyme® Celluclean® Classic, Cellusoft® (Novozymes A/S), Puradax®, Puradax HA, and Puradax EG (available from Genencor International Inc.) and KAC-500(B)™ (Kao Corporation). In an embodiment, the cellulase is obtained from Humicola in particular Humicola insolens. In another embodiment, the cellulase is obtained from Bacillusin, in particular Bacillus akibai. In another embodiment, the cellulase is obtained from Paenibacillus, in particular Paenibacillus polmyxa. In yet another embodiment, the cellulase is obtained from Melanocarpus, in particular Melanocarpus albomyces.

Preferably cellulase comprises the amino acid sequence of SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12 or SEQ ID NO: 13. More preferably the cellulase comprises an amino acid sequence having at least 60%, e.g., at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to the polypeptide of SEQ ID NO 10, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12 or SEQ ID NO: 13. In one aspect, the cellulase comprises amino acid sequence which differ by up to 10 amino acids, e.g., 20 1 , 2, 3, 4, 5, 6, 7, 8, 9, or 10, from the cellulase comprising amino acid sequence of SEQ ID NO: 10, SEQ ID NO: 10, SEQ ID NO: 11 , SEQ ID NO: 12 or SEQ ID NO: 13.

Examples of these cellulase variants are described in WO 2021/058023 A1.

The cellulase enzyme is preferably formulated in a solid form, preferably a granular form. The granular form may be produced as disclosed in US 4,106,991 and US 4,661 ,452, and may optionally be coated by methods known in the art. Examples of waxy coating materials are poly(ethylene oxide) products (polyethyleneglycol, PEG) with mean molar weights of 1000 to 20000, ethoxylated nonylphenols having from 16 to 50 ethylene oxide units; ethoxylated fatty alcohols in which the alcohol contains from 12 to 20 carbon atoms and in which there are 15 to 80 ethylene oxide units; fatty alcohols; fatty acids; and mono- and di- and triglycerides of fatty acids.

Still preferably the cellulase may be formulated as a granule, preferably a co-granule which combines one or more additional enzymes. Non-limiting examples of the additional preferred enzymes includes proteases, amylases, lipases, cellulases, and/or nucleases (e.g., DNase, RNase). Each enzyme will then be present in more granules securing a more uniform distribution of enzymes in the detergent. This also reduces the physical segregation of different enzymes due to different particle sizes. Methods for producing multi-enzyme co-granulate for the detergent industry are known to a person skilled in the art. Another example of cellulase enzymes in the form of co-granulates are disclosed in WO 2013/188331 A1. Also preferred are the enzyme in the form of a granule having a core comprising cellulase enzyme and surrounded by one or more coating layers. The coating layers provide improved storage stability, reduce dust formation, or improve the color or appearance of the granule. The coating layers may include a salt, polyethylene glycol (PEG), methyl hydroxy propyl cellulose (MHPC), and polyvinyl alcohol (PVA).

The cellulase enzyme may also be formulated in an encapsulate form. The cellulase may be encapsulated in a matrix, preferably a water-soluble or water dispersible matrix (e.g., water- soluble polymer particles), for example as described in WO 2016/023685. An example of a water-soluble polymeric matrix is a matrix composition comprising polyvinyl alcohol.

The enzyme may also be encapsulated in core-shell microcapsules, for example as described in WO 2015/144784. Such core-shell capsules can be prepared using a number of technologies known in the art, e.g., by interfacial polymerization using either a water-in-oil or an oil-in-water emulsion, where polymers are crosslinked at the surface of the droplets in the emulsion (the interface between water and oil), thus forming a wall/membrane around each droplet/capsule.

Preferably the cellulase enzyme may also be present as a multienzyme co-granule which in addition to cellulase includes one or more additional preferred enzyme selected from the group consisting of lipases, per hydrolases, peroxidases, laccases, first-wash lipases, proteases, mannanase, reductases, oxidases, nuclease, DNase, amylase, or mixtures thereof.

Preferably the levels of cellulase enzyme in the composition ranges from 0.0001 wt.% to 0.5 wt.%. Preferably the amount of the cellulase present in the composition is at least 0.001 wt.%, still preferably at least 0.01 wt.%, still preferably at least 0.02 wt.%, most preferably at least 0.03 wt.%, but typically not more than 0.3 wt.%, still preferably not more than 0.25 wt.%, most preferably not more than 0.2 wt.%. Levels of enzyme present in the composition preferably relate to the level of enzyme as pure protein.

Substituted polysaccharide:

The biodegradable antiredeposition agent is preferably a substituted polysaccharide.

Preferably the substituted polysaccharide has a functional group present on the polysaccharide backbone, said functional group is selected from the group consisting of alkyl, carboxyalkyl, carboxylic acid, alkoxy or salts thereof. Polysaccharides are chemically modified at one or more of the available hydroxyl groups of the monomeric sugar units to introduce functional group suitably by oxidation, grafting, esterification and etherification in attempts to balance detergent performance and biodegradation. Preferably the polysaccharide is selected from the group consisting of cellulose, inulin, starch, dextrins or mixtures thereof.

The term dextrins includes the group consisting of dextrins, maltodextrins and cyclodextrins. Preferably dextrins have an average degree of polymerization ranging from 3 to 200, still preferably 5 to 100 and most preferably 10 to 40. Dextrins are a group of low molecular weight carbohydrates obtainable by the hydrolysis of starch forming D-glucose units linked by a-(1,4) bonding starting with an a-(1,6) glycosidic bond. Preferably they have a dextrose equivalent between 1 and 30 %, preferably between 1 and 13% based on dextrose (glucose) with 100 %. Dextrose equivalent (DE) is a measure of the amount of reducing sugars present in a sugar product, expressed as a percentage on a dry basis relative to dextrose. The dextrose equivalent gives an indication of the average degree of polymerization (DP) for starch sugars, it is inversely related to the molecular weight. The degree of polymerization (DP) is an indicator of the degree of hydrolysis, unhydrolyzed starch has a DE of 0 while glucose has a DE value of 100. The dextrins are produced from starch using enzymes or by dry heating under acidic conditions (pyrolysis). Maltodextrins are composed of a-(1 ,4) bonding glucose only and have an average polytenization degree of between 10 and 20 and a dextrose equivalent of 3 to 20 %, preferably 10 to 20 %.

The cyclodextrin can be any of the known cyclodextrins such as, unsubstituted cyclodextrins containing from six to twelve glucose monomers, especially, alpha-, beta-, and gammacyclodextrins, and/or their derivatives, and/or mixtures thereof. The alpha-, beta-, and gammacyclodextrins contain 6, 7, and 8 glucose monomer units, respectively, arranged in a donutshaped ring. Examples of cyclodextrin derivatives suitable for use in the present invention include methyl beta-cyclodextrin, hydroxy-ethyl beta-cyclodextrin, and hydroxypropyl betacyclodextrin of different degrees of substitution. Water-soluble cyclodextrin derivatives are preferred cyclodextrin derivatives. Preferably at least a major portion of the cyclodextrins is alpha-, beta- and/or gamma-cyclodextrins, more preferably alpha- and beta-cyclo-dextrins. An especially preferred cyclodextrin for use in the present invention is beta-cyclodextrin. It is also preferred to use mixtures of cyclodextrins. Preferably the levels of substituted polysaccharide in the composition ranges from 0.05 wt.% to 5 wt.%. Preferably the amount of the substituted polysaccharide present in the composition is at least 0.07 wt%, still preferably at least 0.08 wt%, still preferably at least 0.09 wt%, most preferably at least 0.1 wt%, but typically not more than 4 wt.%, still preferably not more than 3 wt.%, most preferably not more than 2 wt.%.

Alkyl substituted polysaccharide:

Preferably the substituted polysaccharide is an alkyl substituted polysaccharide. Alkyl substituted polysaccharide includes an alkyl group which is typically linear or branched Ci to Cs alkyl group or arylalkyl group. Alkyl substituted polysaccharide are preferably manufactured by substitution of hydrogen atoms on the hydroxyl groups of the polysaccharide by alkyl groups and/or arylalkyl groups. The preferred alkyl group is a Ci to C4 alkyl group, examples being methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl. The alkyl group may be substituted by an aromatic radical to form the arylalkyl group, such as with a phenyl radical, for example. One preferred arylalkyl group is benzyl. It is also possible to use mixed alkyl substituted polysaccharide, which contains more than one kind of alkyl, arylalkyl or functionally substituted alkyl group.

Preferred examples of the alkyl substituted polysaccharide include methyl cellulose, ethyl cellulose, propyl cellulose or mixtures thereof.

Hydroxyalkyl substituted polysaccharide:

Preferably the substituted polysaccharide is an hydroxyalkyl substituted polysaccharide. The alkyl and/or arylalkyl groups of the alkyl polysaccharide could further be substituted by nonionic, anionic, cationic, or nonionic groups. The alkyl or arylalkyl group may be functionally substituted, by hydroxyl to form hydroxyalkyl substituted polysaccharide.

Preferred example of hydroxyalkyl substituted polysaccharide includes hydroxyethyl-, hydroxypropyl-, hydroxypropyl methyl cellulose, ethylmethylcellulose cellulose, methylhydroxyethyl cellulose, methylhydroxybutyl cellulose, ethylhydroxydethyl cellulose or mixtures thereof.

Carboxyalkyl substituted polysaccharide:

Preferably the substituted polysaccharide is a carboxyalkyl substituted polysaccharide. The alkyl and/or arylalkyl groups of the alkyl substituted polysaccharide could further be substituted by nonionic, anionic, cationic, or nonionic groups. The alkyl or arylalkyl group may be functionally substituted, by carboxyl or carboxylate group to form carboxyalkyl substituted polysaccharide. When carboxylate groups are present, corresponding counterions are present as well, examples being alkali metal ions such as sodium or potassium, or ammonium ions.

Preferred example of carboxyalkyl substituted polysaccharide includes carboxymethyl cellulose, carboxymethylhydroxyethylcellulose. Among the carboxymethylcelluloses, the preferred examples include sodium carboxymethylcellulose, crosslinked sodium carboxymethyl-cellulose or enzymatically hydrolyzed carboxymethylcellulose.

Another preferred carboxyl substituted polysaccharide is a fructan polycarboxylic acid or salts thereof. A fructan polycarboxylic acid is any oligo-or polysaccharide containing a plurality of anhydrofructan units, and which has been converted into a polycarboxylic acid. The fructans on which a fructan polycarboxylic acid can be based can have a polydisperse chain length distribution and can have a straight or branched chain. Preferably, the fructans contain chiefly p-2,1 bond, as in inulin, but they can also contain p -2, 6 bonds, as in levan. Suitable fructans can originate directly from a natural source, but they can also have undergone a modification. Examples of modifications in this context are reactions known per se which results in lengthening or shortening of the chain length. Suitable fructans have an average chain length (degree of polymerization, DP) of at least 2 up to about 1000. Preferably, a fructan is used with a degree of polymerization of at least 3, more preferably at least 6, most preferably at least 10 up to about 60.

Preferably the fructan polycarboxylic acid has a degree of substitution by carboxyl groups obtained by oxidation of at least 0.05 per original anhydrofructose unit and a degree of substitution by carboxyalkyl or carboxacyl groups of at least 0.1 per anhydrofructose unit.

Preferably the fructan polycarboxylic acid is based on inulin. Inulin is a polysaccharide consisting of p-2,1 bound fructose units with an a-D-glucopyranose unit at the reducing end of the molecule. The principal difference between inulin different natural sources resides in the degree of polymerization. Preferably the degree of polymerization may vary from about 6 to higher than 20, more preferably 6 to 14, still preferably a fructan polycarboxylic acid having a degree of polymerization of 9 to 11. The derivatives of inulin which are used according to the invention are polycarboxylates. Known, suitable polycarboxylate derivatives of inulin are dicarboxy inulin, obtained, for instance, by glycolytic oxidation of inulin, 6-carboxy inulin, obtained, for instance, by selective oxidation of the primary hydroxyl groups of inulin (TEMPO oxidation), carboxymethyl inulin, carboxyethyl inulin, obtained, for instance, by cyanoethylation followed by hydrolysis. Derivatives of inulin which are preferably used are dicarboxy inulin, carboxymethyl inulin and carboxyethyl inulin.

Further, it is possible to use fructan polycarboxylic acids containing carboxyl groups obtained by oxidation of carbon atoms forming part of the anhydrofructose units in the molecule, as well as carboxyl groups obtained by attachment of carboxyalkyl or carboxyacyl groups to the anhydrofructose units. These twofold modified fructan polycarboxylic acids can be prepared by oxidizing a fructan in a known manner, followed by carboxyalkylation or carboxyacylation of the oxidation product in a known manner. It is also possible to change this order around and to have carboxyalkylation or carboxyacylation precede oxidation. In the context of fructan polysaccharide term carboxylic acid include both the free acid and metal or ammonium salts of the carboxylic acid. The term carboxyalkyl refers to a Ci to C4 alkyl group substituted by one or more carboxyl groups, such as carboxymethyl, carboxyethyl, dicarboxymethyl, 1 ,2- dicarboxyethyl or mixtures thereof. The term carboxyacyl refers to a Ci to C4 acyl group, in particular a Ci to C4 alkanoyl or alkenoyl group substituted by one or more carboxyl groups, such as carboxyacetyl, p-carboxypropionyl, p-carboxyacryloyl, y-carboxybutyryl, dicarboxyhydroxybutyryl, and mixtures thereof. As regards the carboxyalkyl and carboxyacyl groups, a preference is expressed for carboxymethyl.

Preferably the fructan polycarboxylic acid has an average, of at least 0.05 carboxyl groups per monosaccharide unit. Depending on the nature of the fructan polycarboxylic acid, the number of carboxyl groups per monosaccharide unit of the fructan polycarboxylic acid can be expressed in the total degree of substitution of carboxyl groups (DS) or the total degree of oxidation (DO).

More preferably, the fructan polycarboxylic acid includes between 0.5 and 3 carboxyl groups per monosaccharide unit. Most preferably the fructan polycarboxylic acid is a carboxymethyl inulin including 0.5 and 3 carboxyl groups per monosaccharide unit.

Carboxylic acid substituted polysaccharide:

Preferably the substituted polysaccharide is a carboxylic acid substituted polysaccharide. Nonlimiting example of carboxylic acid substituted polysaccharide includes acrylic acid substituted polysaccharide, malic acid substituted polysaccharide, succinic acid substituted polysaccharide, most preferred are the acrylate substituted polysaccharide. Non-limiting example of the carboxylic acid substituted polysaccharide is acrylated starch.

More preferably the substituted polysaccharide is selected from carboxyalkyl polysaccharide, carboxylic acid polysaccharide or mixtures thereof. Still more preferably the carboxyalkyl polysaccharide is selected from carboxymethyl cellulose, carboxymethyl inulin or mixtures thereof. Preferably the carboxylic acid polysaccharide is an acrylic acid substituted polysaccharide or salts thereof, still preferably an acrylic acid substituted starch or salts thereof.

Copolymer of acrylic acid and maleic acid

According to a first aspect of the present invention disclosed is a solid laundry composition having an acrylic acid maleic acid copolymer. The term maleic acid as used herein includes both maleic acid, maleic anhydride and/or salts thereof. The term acrylic acid as used herein includes acrylic acid, methacrylic acid and/or salts thereof.

The copolymer of acrylic acid and maleic acid or salt thereof has a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1 :1 to 1 :9. More preferably the weight ratio of acrylic acid segment to the maleic acid segment ranges from 1 :1 to 1 :8, still preferably from 1 :1 to 1 :6, still more preferably from 1 :1 to 1 :5.

Alternately, the copolymer of acrylic acid and maleic acid or salt thereof has a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1 :1.5 to 1 :9, still more preferably from 1 :2 to 1 :9, furthermore preferably from 1 :2.5 to 1 :9, still further preferably from 1 :3 to 1 :9, still furthermore preferably from 1 :3.5 to 1 :9. In yet another embodiment copolymer of acrylic acid and maleic acid or salt thereof has a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1 :4 to 1 :8, more preferably from 1 :5 to 1 :8, also preferably from 1 :6 to 1 :8.

Water-soluble salts of the copolymer of acrylic acid and maleic acid having a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1 : 1 to 1 :9 is also suitable for the present invention. The salts include those selected from non-limiting examples selected from alkali metal, ammonium and substituted ammonium salts. The copolymer of acrylic acid and maleic acid includes from 10 weight percent to 50 weight percent acrylic acid and 50 weight percent to 90 weight percent maleic acid. Still preferably from 10 weight percent to 40 weight percent acrylic acid and 60 weight percent to 90 weight percent maleic acid.

Optionally, the solid laundry composition may include additional acrylic acid and maleic acid copolymer having from 60 weight percent to 90 weight percent acrylic acid and 10 weight percent to 40 weight percent maleic acid.

Preferably such additional copolymer of acrylic acid and maleic acid having the acrylic acid in a higher weight percent, that is a copolymer having 60 weight percent to 90 weight percent acrylic acid and 10 weight percent to 40 weight percent maleic acid, the acrylic acid maleic acid copolymer has a weight average molecular weight ranging from 10,000 to 120,000, preferably 50,000 to 100,000, more preferably 60,000 to 100,000, and most preferably 60,000 to 90,000. To ensure high water solubility, the acrylic acid maleic acid copolymer should preferably be partially or fully neutralized. Preferably the additional copolymer of acrylic acid and maleic acid has 70 weight percent acrylic acid and 30 weight percent maleic acid. A preferred example of the additional acrylic acid maleic acid copolymer is Sokalan CP5 from BASF.

Preferably the copolymer of acrylic acid and maleic acid according to the present invention including from 10 weight percent to 50 weight percent acrylic acid and 50 weight percent to 90 weight percent maleic acid (a weight ratio of acrylic acid segment to the maleic acid segment from 1 :1 to 1 :9), has a weight average molecular weight ranging from 500 to 7000 still preferably from 500 to 4000, still more preferably from 2000 to 4000.

It is highly preferred that the copolymer of acrylic acid and maleic acid according to the present invention has a weight average molecular weight in the range from 500 to 7000 and a weight ratio of acrylic acid segment to the maleic acid segment from 1 :1 to 1 :9, more preferably 1 :1 to 1 :5; still preferably weight average molecular weight in the range from 500 to 4000 and a weight ratio of acrylic acid segment to the maleic acid segment from 1 :1 to 1 :9, more preferably 1 :1 to 1 :5; and still further preferably where the weight average molecular weight in the range from 2000 to 4000 and a weight ratio of acrylic acid segment to the maleic acid segment from 1 :1 to 1:9, more preferably from 1:1 to 1 :5.

The solid laundry composition includes from 0.02 wt.% to 0.5 wt.% acrylic acid maleic acid copolymer. Preferably the levels of acrylic acid maleic acid copolymer in the composition ranges from 0.03 wt.% to 0.5 wt.%. Preferably the amount of the acrylic acid maleic acid copolymer present in the composition is at least 0.022 wt%, still preferably at least 0.025 wt%, still preferably at least 0.028 wt%, most preferably at least 0.03 wt%, but typically not more than 0.45 wt.%, still preferably not more than 0.4 wt.%, still more preferably not more than 0.35 wt.%, most preferably not more than 0.3 wt.%.

Solid laundry composition

A solid laundry composition according to the present disclosure encompasses a variety of spray-dried or granulated forms including, for example powder, particulates; cast and extruded forms including, for example, solids, needles, pellets, blocks, bars, and tablets. The term “solid” refers to the state of the laundry composition under the expected conditions of storage and use of the solid laundry composition. In general, it is expected that the laundry composition will remain a solid when provided at a temperature of up to about 37°C and preferably greater than 50°C.

The composition according to the present invention preferably has a pH from 7.0 to 13, preferably 7.0 to 12.5, still preferably 7.0 to 12, still further preferably from 8.5 to 9, when measured at 1 wt.% dilution in de-ionised water at 25°C. The composition may preferably include a buffer.

The laundry composition of the present invention is in the solid form. The laundry composition according to the present invention may be made via a variety of conventional methods known in the art and those which includes but is not limited to the mixing of ingredients, including drymixing, wet granulation, compaction such as agglomerating, extrusion, tabletting, or spraydrying of the various compounds comprised in the detergent component, or mixtures of these techniques, whereby the components herein also can be made by for example compaction, including extrusion and agglomerating, or spray-drying. The laundry composition may be made by any of the conventional processes, especially preferred is the technique of slurry making and spray drying or agglomeration. The compositions herein can take a variety of physical solid forms including forms such as powder, granule, ribbon, noodle, paste, tablet, flake, pastille, and bar, and preferably the composition is in the form of powder, granules or a tablet, still preferably the composition is in the form of a powder. The laundry composition may be in the form of a unit dose formulation, delayed delivery formulation, detergent contained on or in a porous substrate or nonwoven sheet, and other suitable forms that may be apparent to one skilled in the art in view of the teachings herein. The composition according to the present invention may preferably be in a form selected from powder, unit dose or pouch form, tablet, bar, or flake.

The solid laundry detergent composition according to the present invention is preferably free flowing. The composition is preferably a fully formulated detergent composition. The solid detergent composition includes but is not limited to powder, granular, particulate, agglomerates, noodles, flakes tablets, bar, sheet, or other solid forms known in the art and combinations thereof.

Preferably the composition is used for laundering fabrics using manual-washing method. Preferably, the composition of the present invention is a solid laundry detergent composition in the form of a spray -dried powder or particulate free-flowing form.

The compositions preferably have a density of more than 350 grams/litre, more preferably more than 450 grams/litre or even more than 570 grams/litre. More preferably the solid laundry composition has a bulk density ranging from 350 grams/litre to 800 grams/litre.

Surfactant

The solid laundry composition according to the first aspect of the present invention preferably includes a surfactant.

The surfactant includes those selected from the group consisting of anionic surfactant, cationic surfactant, amphoteric surfactant, zwitterionic surfactant, nonionic surfactant, or combinations thereof.

Examples of anionic surfactant are given in "Surface Active Agents and Detergents" (Vol. I and II by Schwartz, Perry and Berch). Suitable anionic surfactants include those selected from the group consisting of alkyl sulfates, alkyl sulfonates, alkylaryl sulfonates, alkyl sulfosuccinates, alkyl ether sulfosuccinates, alkyl sulfosuccinamates, alkyl amidosulfosuccinates, alkyl carboxylates, alkyl amido ether carboxylates, alkyl succinates, fatty acyl sarcosinates, fatty acyl amino acids, fatty acyl taurates, fatty alkyl sulfoacetates, alkyl phosphates, and mixtures of two or more thereof. Non-limiting examples of the preferred anionic surfactant includes linear alkyl benzene sulphonate, primary alkyl sulfate, methyl ester sulphonate or combinations thereof.

Sulphate surfactant:

Suitable sulphate surfactant includes Cs to C20 alkyl sulphate, preferably Cs to C18 alkyl sulphate, still preferably C12 to C14 alkyl sulphate, more preferably it is predominantly C12 alkyl sulphate. The alkyl sulphate surfactant may be linear or branched, substituted or un-substituted, and may be derived from petrochemical material or biomaterial. Preferably the alkyl sulphate surfactant is linear. Still preferably it is preferred that the alkyl sulphate surfactant is a C10 to C14 alkyl sulphate surfactant, most preferably a lauryl sulphate surfactant.

Conventional primary alkyl sulfate surfactant has the general formula: R"OSOs'M ⁺ wherein R" is typically a Cs to C20 alkyl group, which may be straight chain or branched chain, and M is a water-solubilizing cation. In specific embodiments, R" is a C10 to C15 alkyl group, and M is alkali metal, more specifically R" is C12 to C14 alkyl and M is sodium. Specific, non-limiting examples of anionic alkyl sulphate surfactant useful herein include: C10 to C20 primary, branched-chain and random alkyl sulfates (AS); or C10 to Cis secondary (2,3)-alkyl sulfates having following formulae: wherein M is hydrogen or a cation which provides charge neutrality, and all M units, can either be a hydrogen atom or a cation depending upon the form isolated or the relative pH of the system wherein the surfactant is used, with non-limiting examples of preferred cations including sodium, potassium, ammonium, and mixtures thereof, and x is an integer of at least about 7, preferably at least about 9, and y is an integer of at least 8, preferably at least about 9.

A preferred sulphate surfactant is alkyl alkoxylated sulphate, preferably alkyl ethoxylated sulphate, preferably a Cs to Cis is alkyl alkoxylated sulphate, preferably a Cs to Cis alkyl ethoxylated sulphate, preferably the alkyl alkoxylated sulphate has an average degree of alkoxylation of from 0.5 to 20, preferably from 0.5 to 10, preferably the alkyl alkoxylated sulphate is a Cs to Cis alkyl ethoxylated sulphate having an average degree of ethoxylation of from 0.5 to 10, preferably from 0.5 to 5, more preferably from 0.5 to 3 and most preferably from 0.5 to 1.5. The alkyl alkoxylated sulphate surfactant may be linear or branched, substituted or un-substituted, and may be derived from petrochemical material or biomaterial. Preferably the sulphate surfactant is a linear or branched, substituted or unsubstituted Cs to Cis alkyl sulphate surfactant, Cs to Cis alkyl ether sulphate surfactant or mixtures thereof.

Sulphonate surfactant:

Suitable sulphonate detersive surfactant include methyl ester sulphonate, alpha olefin sulphonates, alkyl benzene sulphonate, especially alkyl benzene sulphonate, preferably Cw to C14 alkyl benzene sulphonate. Suitable alkyl benzene sulphonate (LAS) is obtainable, preferably obtained, by sulphonating commercially available linear alkyl benzene (LAB); suitable LAB includes low 2-phenyl LAB, other suitable LAB includes high 2-phenyl LAB, such as those supplied by Sasol under the tradename Hyblene®. The sulphonate surfactant may be linear or branched, substituted or un-substituted, and may be derived from petrochemical material or biomaterial. The sulphonate surfactant is preferably a linear or branched, substituted or unsubstituted C to C14 alkyl benzene sulphonate. The sulphonate surfactant may also be selected from the modified alkylbenzene sulfonate (MLAS) as discussed in WO 99/05243, WO 99/05242 and WO 99/05244; methyl ester sulfonate (MES); and alpha-olefin sulfonate (AOS).

Anionic surfactants may exist in an acid form and the acid form may be neutralized to form a surfactant salt. Typical agents for neutralization include a metal counter ion base such as a hydroxide, e.g., NaOH or KOH. Further agents for neutralizing anionic surfactants include ammonia, amines, or alkanolamines. Suitable non-limiting examples include monoethanolamine, diethanolamine, triethanolamine, and other linear or branched alkanolamines known in the art, for example, 2-amino-1-propanol, 1-aminopropanol, monoisopropanolamine, or 1-amino-3-propanol.

Preferably the anionic surfactant is a non-soap anionic surfactant. The term “soap” is used herein in its popular sense, i.e. , the alkali metal or alkanol ammonium salts of aliphatic, alkanes, or alkene monocarboxylic acids.

Preferably the anionic surfactant includes 0 wt.% to 20 wt.% alkyl sulfates, preferably 0 wt.% to 15 wt.% alkyl sulfates, preferably 0 wt.% to 10 wt.% alkyl sulfates, preferably PAS. The anionic surfactant may also include from 0 wt.% to 10 wt.% MES, preferably 0 wt.% to 5 wt.% MES.

The detergent composition of the present invention includes from 2 wt.% to 50 wt.% of anionic detersive surfactant, most preferably from 2 wt.% to 25 wt.% anionic surfactant. Preferably the detergent composition comprises at least 4 wt.%, still preferably at least 5 wt.%, still preferably at least 8 wt.%, still preferably at least 10 wt.%, still more preferably at least 12 wt.% of the anionic surfactant, most preferably at least 15 wt.% of the anionic surfactant, but typically not more than 45 wt.%, still preferably not more than 40 wt.%, still further preferably not more than 35 wt.%, still more preferably not more than 30 wt.% and most preferably not more than 25 wt.%, still more preferably not more than 20 wt.% of an anionic surfactant based on the weight of the detergent composition.

Non-ionic surfactant:

Non-limiting examples of nonionic surfactants include: C12 to C18 alkyl ethoxylates, Ce to C12 alkyl phenol alkoxylates wherein the alkoxylate units are a mixture of ethyleneoxy and propyleneoxy units; C12 to C18 alcohol and Ce to C12 alkyl phenol condensates with ethylene oxide/propylene oxide block alkyl polyamine ethoxylates alkyl polysaccharides and ether capped poly(oxyalkylated) alcohol surfactants.

Cationic surfactant:

Non-limiting examples of cationic surfactants include: the quaternary ammonium surfactants, which can have up to 26 carbon atoms include: alkoxylate quaternary ammonium (AQA) surfactants, dimethyl hydroxyethyl quaternary ammonium, dimethyl hydroxyethyl lauryl ammonium chloride; polyamine cationic surfactants and cationic ester surfactants.

Zwitterionic surfactant:

Non-limiting examples of zwitterionic or ampholytic surfactants include derivatives of secondary and tertiary amines, derivatives of heterocyclic secondary and tertiary amines, or derivatives of quaternary ammonium, quaternary phosphonium or tertiary sulfonium compounds. Examples of zwitterionic surfactants includes betaines, including alkyl dimethyl betaine and coco dimethyl aminopropyl betaine, Cs to C18 (for example from C12 to Cis) amine oxides and sulfo and hydroxy betaines, such as N-alkyl-N, N-dimethylammino-1-propane sulfonate where the alkyl group can be Cs to Cis and in certain embodiments from C10 to C14.

The solid laundry composition preferably has a combination of anionic surfactants. Preferably the anionic surfactant is selected from alkyl benzene sulphonate surfactant, alkyl sulphate surfactant, alkyl ether sulfate surfactant or mixtures thereof. Preferably the total amount of the alkyl sulphate surfactant and alkyl ether sulfate surfactant in the composition is lower than 50 wt.% of the total anionic surfactant present in the composition, still preferably the total amount of the alkyl sulphate surfactant and alkyl ether sulfate surfactant in the composition is lower than 50 wt.% of the total surfactant content present in the composition.

Alternately the total amount of the alkyl sulphate surfactant and alkyl ether sulfate surfactant in the composition is higher than 50 wt.% of the total anionic surfactant present in the composition, still preferably the total amount of the alkyl sulphate surfactant and alkyl ether sulfate surfactant in the composition is higher than 50 wt.% of the total surfactant content present in the composition.

Still preferably the solid laundry composition may include a combination of anionic surfactant and nonionic surfactant. Preferably the anionic surfactant is either or both alkyl sulphate surfactant and alkyl ether sulfate surfactant. Preferably the total amount of the alkyl sulphate surfactant, alkyl ether sulfate surfactant and nonionic surfactant in the composition is higher than 50 wt.% of the total surfactant content present in the composition.

Carbonate builder

The detergent composition of the present invention preferably includes a carbonate builder. In addition to the carbonate builder the composition may also include sodium bicarbonate, potassium carbonate, sodium sesquicarbonate or mixtures thereof.

The detergent composition of the present invention includes from 0 wt.% to 35 wt.% carbonate builder, more preferably from 0 wt.% to 20 wt.%. Preferably the detergent composition comprises at least 3 wt.%, still preferably at least 5 wt.%, still preferably at least 8 wt.%, most preferably at least 10 wt.% of the carbonate builder, most preferably at least 12 wt.% of the carbonate builder but typically not more than 30 wt.%, still preferably not more than 28 wt.%, most preferably not more than 25 wt.%, most preferably not more than 22 wt.% of carbonate builder based on the weight of the laundry detergent composition. The carbonate builder may include 100 wt.% alkali carbonate builder, preferably sodium carbonate builder or may be a combination of alkali metal carbonate, alkali metal bicarbonate, alkali metal sesquicarbonate or combination thereof.

Silicate salt The detergent composition of the present invention preferably includes a silicate salt. The silicate salt is preferably an alkali metal silicate salt which acts as an alkalinity agent and a builder in the solid detergent composition.

Suitable silicates include the water-soluble sodium silicates with an SiCh: Na2O ratio of from 1.0 to 2.8, with ratios of from 1.6 to 2.4 being preferred, and 2.0 ratio being most preferred. The silicates may be in the form of either the anhydrous salt or a hydrated salt. Sodium silicate with an SiCh: Na2O ratio of 2.0 is the most preferred silicate.

Silicates are preferably present in the solid laundry compositions in accordance with the invention at a level ranging from 0 wt.% to 17 wt.% by weight of the composition, more preferably from 0 wt.% to 15 wt.%, even more preferably from 0 wt.% to 13 wt.% in the solid laundry composition.

The composition of the present invention preferably includes from 0 wt.% to 17 wt.%, still preferably from 0 wt.% to 15 wt.%, more preferably from 0 wt.% to 8 wt.% silicate salt, still preferably 0 wt.% to 5 wt.%, and still more preferably 0 wt.% to 1 wt.% silicate salt. Preferably the composition of the present invention is substantially free of silicate salt. By substantially free it is meant that there is no deliberately added carbonate salt in the composition.

Inorganic salts:

The solid laundry composition of the present invention preferably includes inorganics salts selected from the group consisting of calcite, dolomite, magnesium carbonate or mixtures thereof. The composition of the present invention preferably includes from 0 wt.% to 10 wt.%, still preferably from 0 wt.% to 6 wt.%, more preferably from 0 wt.% to 5 wt.% inorganics salts selected from calcite, dolomite or mixtures thereof.

The solid laundry composition of the present invention preferably includes soluble inorganic salts selected from the group consisting of alkali metal sulphate, alkali metal chloride, alkaline earth metal sulphate or mixtures thereof. More preferably the composition includes soluble inorganic salts selected from the group consisting of sodium sulphate, sodium chloride, magnesium sulphate or mixtures thereof. Preferably the composition of the present invention includes from 10 wt.% to 60 wt.%, still preferably from 15 wt.% to 50 wt.%, more preferably from 15 wt.% to 40 wt.% soluble inorganics salts. Biodegradable chelating agent

The solid laundry composition may preferably include a biodegradable chelating agent. Nonlimiting examples of the biodegradable chelating agent includes MGDA, GLDA, gluconate or mixtures thereof. More preferably the biodegradable chelating agent is gluconate. The composition of the present invention preferably includes from 0 wt.% to 10 wt.%, still preferably from 0 wt.% to 6 wt.%, more preferably from 0 wt.% to 5 wt.%, even more preferably 0 wt.% to 3 wt.% biodegradable chelating agents, more preferably gluconate.

Bleach and Bleach activator

The solid laundry composition of the present invention may include a bleach. The bleach is preferably selected from percarbonate bleach. More preferably a bleach activator is present. An example of bleach activator includes TAED, other known bleach activators may also be used.

Bleach system generally includes a bleach and a bleach activator. Preferably the solid laundry composition includes 0 wt.% to 6 wt.% bleach, still preferably from 0 wt.% to 5 wt.% bleach, still more preferably from 0 wt.% to 3 wt.% bleach.

Preferably the total amount of the bleach and bleach activator present in the composition of the present invention ranges from 0 wt.% to 10 wt.%, more preferably 0 wt.% to 8 wt.%, still preferably from 0 wt.% to 5 wt.% and still more preferably from 0 wt.% to 3 wt.%.

Preferably the solid laundry composition comprises 0 wt.% boron-based bleach. Example of the boron-based bleach includes sodium perborate. Preferably the solid laundry composition comprises 0 wt.% boron-based bleach activator.

Moisture content

The solid laundry composition includes from 1 wt.% to 3.5 wt.%, still preferably 1 wt.% to 3 wt.% water. Preferably the solid laundry composition is either agglomerated or spray-dried.

The solid laundry composition according to the present invention preferably has from 0 wt.% to 4 wt.% zeolite builder. Preferably the amount of zeolite builder is less than 3 wt.%, still preferably less than 2.5 wt.%, more preferably less than 2 wt.% by weight in the detergent composition and most preferably the detergent composition is substantially free of zeolite builder. The solid laundry detergent composition according to the present invention preferably has from 0 wt.% to 2 wt.% phosphorus containing chemicals. Preferably the phosphorous containing chemicals includes STPP, HEDP or mixtures thereof. Preferably the amount of phosphorus containing chemicals is less than 2 wt.%, still preferably less than 1.5 wt.%, more preferably less than 1 wt.% by weight in the solid laundry composition and most preferably the solid laundry composition is substantially free of phosphorus containing chemicals. Preferably the composition includes 0 wt.% to 2 wt.% STPP. Still preferably the solid laundry composition is substantially free of STPP. Preferably the composition includes 0 wt.% to 2 wt.% HEDP. Still preferably the solid laundry composition is substantially free of HEDP. Preferably the composition includes 0 wt.% STPP. Preferably the composition includes 0 wt.% HEDP.

The term “substantially free” means that the indicated component is at the very minimum, not deliberately added to the composition to form part of it. It is meant to include compositions whereby the indicated material is present only as an impurity in one of the other materials deliberately included.

Optional ingredients

The solid laundry composition of the present invention may preferably include one or more of the optional ingredients selected from the group consisting of cleaning and care ingredients. The optional ingredients include one or more adjunct cleaning additives selected from polymers, further enzymes, enzyme stabilizer, brightening agents, whitening agent, bleach, humectant, perfume, filler or carrier, an alkalinity system, a buffer, or combinations thereof.

Cleaning and care polymers:

The composition of the present invention may preferably include polymers which provide cleaning or care benefits. The cleaning polymer includes but is not limited to soil release polymer, antiredeposition polymers, care polymers, amphiphilic alkoxylated grease cleaning polymers, clay soil cleaning polymers, soil suspending polymers or mixtures thereof.

Suitable further carboxylate polymer may preferably include polyacrylic acid, polymethacrylic acid, polymaleic acid, copolymers of maleic acid with vinyl methyl ether or mixtures thereof.

Anti-redeposition polymers are designed to suspend or disperse soil. Typically, antiredeposition polymers in addition to those already discussed above may preferably include those selected from polyethylene glycol polymers, polyethyleneimine polymers or mixtures thereof. Soil release polymers are designed to modify the surface of the fabric to facilitate the ease of removal of soil. Suitable soil release polymers are sold by Clariant under the TexCare® series of polymers, e.g., TexCare® SRN240, TexCare® SRN 100, TexCare® SRN 170, TexCare® SRN300, TexCare® SRN325, TexCare® SRA100 and TexCare® SRA300. Other suitable soil release polymers are sold by Rhodia under the Repel-o-Tex® series of polymers, e.g., Repel-o- Tex® SF2, Repel-o-Tex® SRP6 and Repel-o-Tex® Crystal. A preferred polymer is selected from the group consisting of polyester soil release polymer, both end-capped and non-end- capped sulphonated PET/POET polymers, both end-capped and non-end-capped unsulphonated PET/POET polymers or combinations thereof.

Preferably the levels of these soil release polymer in the detergent composition ranges from 0 wt.% to 5 wt.%, at least 0.1 wt%, still preferably at least 0.25 wt.%, still preferably at least 0.3 wt.%, but typically not more than 5 wt%, still preferably not more than 3 wt%, still preferably not more than 1 wt.%, more preferably no more than 0.5 wt.%.

Suitable care polymers include cellulosic polymers that are cationically modified or hydrophobically modified. A suitable commercially available dye lock polymer is Polyquart® FDI (Cognis). Preferably the adjunct particle includes from 0.01% to 10%, preferably from 0.05% to 0.5% by weight of care polymer.

Examples of suitable sequestering polymers are DEQUEST™, organic phosphonate type sequestering polymers sold by Monsanto and alkanehydroxy phosphonates.

The solid laundry composition is preferably substantially free of phosphate based sequestering polymers. By substantially free, it is meant herein that no phosphate based sequestering polymers is deliberately added.

Enzymes:

The composition of the present invention preferably includes one or more further enzymes. Preferred examples of the further enzymes include those which provide cleaning performance and/or fabric care benefits.

Examples of suitable further enzymes include, but are not limited to, hemicellulases, peroxidases, proteases, xylanases, lipases, xyloglucanase, phospholipases, esterases, cutinases, pectinases, mannanases, pectate lyases, keratinases, reductases, oxidases, phenoloxidases, lipoxygenases, ligninases, pullulanases, tannases, pentosanases, malanases, G-glucanases, arabinosidases, hyaluronidase, chondroitinase, laccase, and amylases, or mixtures thereof. A typical combination is an enzyme cocktail that may comprise, for example, a protease and lipase in conjunction with one or more of amylase and mannanase. When present in a solid laundry composition, the further enzymes may be present at levels from about 0.00001% to about 2%, from about 0.0001% to about 1% or from 0.001% to about 0.5% enzyme protein by weight of the solid laundry composition.

Suitable proteases include metalloproteases and serine proteases, including neutral or alkaline microbial serine proteases, such as subtilisins (EC 3.4.21.62). Suitable commercially available protease enzymes include those sold under the trade names Alcalase®, Savinase®, Primase®, Durazym®, Polarzyme®, Kannase®, Liquanase®, Liquanase Ultra®, Savinase Ultra®, Ovozyme®, Neutrase®, Everlase® and Esperase® by Novozymes A/S (Denmark), those sold under the tradename Maxatase®, Maxaca®l, Maxapem®, Properase®, Purafect®, Purafect Prime®, Purafect Ox®, FN3®, FN4®, 10 Excellase® and Purafect OXP® by Genencor International, those sold under the tradename Opticlean® and Optimase by Solvay Enzymes.

Suitable alpha-amylases include those of bacterial or fungal origin. Suitable commercially available alpha-amylases include DURAMYL®, LIQUEZYME®, TERMAMYL®, TERMAMYL ULTRA®, NATALASE®, SUPRAMYL®, STAINZYME®, STAINZYME PLUS®, FUNGAMYL® and BAN® (Novozymes A/S, Bagsvaerd, Denmark), 15 KEMZYM® AT 9000 Biozym Biotech Trading GmbH Wehlistrasse 27b A-1200 Wien Austria, RAPIDASE®, PURASTAR®, ENZYSIZE®, OPTISIZE HT PLUS®, POWERASE® and PURASTAR OXAM® (Genencor International Inc., Palo Alto, California) and KAM® (Kao, 14-10 Nihonbashi Kayabacho, 1- chome, Chuo-ku Tokyo 103-8210, Japan). In one aspect, suitable amylases include NATALASE®, STAINZYME and STAINZYME PLUS® and mixtures thereof.

In one aspect, such enzymes may be selected from the group consisting of: lipases, including "first cycle lipases". Preferred lipases would include those sold under the tradenames Lipex® and Lipolex®.

Other preferred enzymes include pectate lyases sold under the tradenames Pectawash®, Pectaway®, Xpect® and mannanases sold under the tradenames Mannaway® (all from Novozymes A/S, Bagsvaerd, Denmark), and Purabrite® (Genencor International Inc., Palo Alto, California). Enzyme stabilizing system:

The enzyme-containing compositions described herein may optionally comprise from 0.001% to 10%, in some examples from about 0.005% to about 8%, and in other examples, from about 0.01% to about 6%, by weight of the composition, of an enzyme stabilizing system. The enzyme stabilizing system can be any stabilizing system which is compatible with the detersive enzyme. Such stabilizing systems can, for example, comprise calcium ion, propylene glycol, short chain carboxylic acids, chlorine bleach scavengers and mixtures thereof, and are designed to address different stabilization problems depending on the type and physical form of the cleaning composition.

Whitening agents:

The solid laundry composition may optionally include whitening agents selected from optical brighteners, fabric hueing agents or mixtures thereof

Optical brighteners:

Optical brighteners or other brightening or whitening agents may be incorporated at levels from 0.01% to 1.2%, by weight of the composition. More preferably the composition includes from 0.01 wt.% to 0.4 wt.% optical brightener. Commercial brighteners suitable for the present invention can be classified into subgroups, including but not limited to: derivatives of stilbene, pyrazoline, coumarin, benzoxazoles, carboxylic acid, methinecyanines, dibenzothiophene-5, 5- dioxide, azoles, 5- and 6-membered-ring heterocycles, and other miscellaneous agents. Preferred commercially available Brighteners includes Tinopal AMS-GX by Ciba Geigy Corporation, Tinopal UNPA-GX by Ciba-Geigy Corporation, Tinopal 5BM-GX by Ciba-Geigy Corporation. The brighteners may be added in particulate form or as a premix with a suitable solvent, for example nonionic surfactant, monoethanolamine, propane diol.

Fabric hueing agents:

The composition may comprise a fabric hueing agent (sometimes referred to as shading, or bluing agents). Typically, the hueing agent provides a blue or violet shade to fabric. Hueing agents can be used either alone or in combination to create a specific shade of hueing and/or to shade different fabric types. Hueing agents may include dyes, dye-clay conjugates, and organic and inorganic pigments. Preferred fabric hueing agents includes AV50, DV9, DV28, T48 or mixtures thereof. Preferably the composition includes from 0 wt.% to 0.005 wt.% shading dye, still more preferably 0.0005 wt.% to 0.005 wt.% shading dye. Some composition may include 0 wt.% shading dye to improve the biodegradability index of the composition.

Methods of laundering:

According to a second aspect of the present invention, disclosed is a method for laundering a textile surface with the solid laundry composition according to the first aspect of the present invention comprising the steps of: iv) preparing an aqueous wash liquor by contacting the solid laundry composition according to the first aspect with a liquid; v) soaking said textile surface in the wash liquor for a predetermined period of time; and, vi) optionally rinsing the textile surface.

The compositions are preferably employed at concentrations of from about 200 ppm to about 15,000 ppm in solution. Preferably the liquid is water. Preferably the water temperature preferably ranges from 5°C to 100°C.

Machine laundry methods herein typically comprise treating soiled textile fabric with an aqueous wash solution in a washing machine having dissolved or dispensed therein an effective amount of the solid laundry composition in accordance with the invention. By an effective amount of the solid laundry composition, it is meant from 20 g to 300 g of product dissolved or dispersed in a wash solution of volume from 5 to 65 liters, as are typical product dosages and wash solution volumes commonly employed in conventional machine laundry methods. Hand-washing methods, and combined handwashing with semi-automatic washing machines are also included.

According to a third aspect of the present invention disclosed is the use of a biodegradable antiredeposition agent and 0.02 wt.% to 0.5 wt.% acrylic maleic copolymer wherein the copolymer of acrylic acid and maleic acid has a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1 :1 to 1:9 in a solid laundry composition to provide improved cleaning performance.

Preferably the improved cleaning performance is as compared to a composition having 0.02 wt.% to 0.5 wt.% copolymer of acrylic acid and maleic acid wherein the the copolymer of acrylic acid and maleic acid has a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1.5:1 to 9:1. According to yet another aspect of the present invention, disclosed is a use of a biodegradable antiredeposition agent and from 0.02 wt.% to 0.5 wt.% copolymer of acrylic acid and maleic acid wherein the copolymer of acrylic acid and maleic acid has a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1 :1 to 1 :9 in a solid laundry composition for exhibiting improved biodegradability.

Preferably the improved biodegradability is as compared to a composition having 0.02 wt.% to 0.5 wt.% copolymer of acrylic acid and maleic acid wherein the copolymer of acrylic acid and maleic acid has a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1.5:1 to 9:1.

The invention will now be illustrated more fully with the aid of the following non-limiting examples. It will be appreciated that other modifications of the present invention within the skill of those in the art can be undertaken without departing from the spirit and scope of this invention. All of the formulations exemplified hereinafter are prepared via conventional formulation and mixing methods unless specific methods are given. All parts, percentages, and ratios herein are by weight unless otherwise specified.

Examples

Example 1

A spray-dried solid laundry composition in accordance with the present invention was prepared by spray drying an aqueous slurry in a counter current spray drier. The composition of a spray- dried solid laundry detergent composition according to the present invention (Ex 1) and a composition having higher levels of acrylic maleic copolymer (Ex A) are provided in table 1.

Table 1

The composition according to the present invention (Ex 1) having a biodegradable antiredeposition agent (cellulase enzyme) and low levels of the copolymer of acrylic acid and maleic acid was found to provide good cleaning performance and had good biodegradability.

Example 2

Spray-dried solid laundry compositions in accordance with the present invention was prepared by spray drying an aqueous slurry of the ingredients provided in the table 2 below, in a counter current spray drier. The acrylic maleic acid copolymer and cellulase enzyme was post dosed to the spray-dried powder. The composition of a spray-dried solid laundry detergent composition according to the present invention (Ex 2, Ex 3, Ex 4) and comparative solid laundry detergent composition (Ex B, Ex C and Ex D) are provided in table 2.

Each of the composition provided in the table 2 was evaluated for their anti-redeposition benefits. For this, an amount of 1.5 gram/litre of the solid laundry composition was added to tergo-to-meter having 500 mL of water (water hardness 6FH Ca ²⁺ : Mg ²⁺ 2:1) and the device was run for 2 minutes at a speed of 100 rpm and a water temperature of 25°C. Next, 2 types of standard commercially available soil strips were added to the wash liquor and the machine was run for another 2 minutes at a speed of 100 rpm and maintaining the water temperature of 25°C. These soil strips included an amount of 2 grams/Litre of SBL soil emulsion and an amount of 1.5 grams/Litre of Stanley clay soil. Thereafter 5 pieces of woven cotton cloth swatches (Woven Cotton-CN11 type) were added and laundered using a soak, wash and rinse protocol. In this protocol, the soaking time was 20 minutes which was followed by a 15-minute washing cycle and thereafter with 2 rinse cycles of 2 minutes each. The cloth swatches were dried and the R460 value was measured for all 5 cloth swatches and then their average R460 value was calculated and recorded.

Before the cloth swatches were washed their reflectance value measured in R460 values, was determined using a Xrite CI7600 Spectrophotometer (supplied by Advanced Graphic Systems). The values were recorded as 460 (unwashed). The R460 value of the 5 washed and dried cloth swatches were recorded and average value was calculated and recorded as R460 (washed).

Soil redeposition was measured as the difference (A R460) between the R460 values which was calculated as follows: A R460 = average R460 (unwashed) - average R460 (washed).

Higher values of A R460 indicate higher difference in whiteness of the unwashed cloth and the washed cloth. Therefore, higher difference indicates that the clothes were lesser white after wash. In other words, it indicates higher levels of soil redeposition. Therefore, compositions that provided lower values of A R460 were preferred.

Table 2

The soil redeposition data in the table 2 above demonstrates that the composition (Ex 2, Ex 3, Ex 4) according to the present invention having the acrylic acid maleic acid copolymer (acrylic acid maleic acid weight ratio 1:1) according to the invention and biodegradable antiredeposition agent provides improved anti-redeposition benefits and provides improved cleaning performance as compared to the comparative composition (Ex B, Ex C, Ex D). Also, as seen from the results in the table 2, the solid laundry detergent composition according to the present invention having 0.06 wt.% of the acrylic maleic acid copolymer with a weight ratio of acrylic acid segment to the maleic acid segment ranging from 1.5:1 to 9:1 , provides better cleaning performance and antiredeposition benefits than those provided by the comparative composition with higher levels (0.3 wt.%, Ex C) of the acrylic maleic acid copolymer with a weight ratio of acrylic acid segment to the maleic acid segment outside the claimed ranges. Thus, lesser amount of the copolymer according to the present invention in combination with cellulase enzyme (biodegradable antiredeposition agent) provides desirable cleaning performance and antiredeposition benefits. Hence, the solid laundry detergent composition according to the present invention provides desired cleaning performance while achieving better biodegradability.