Particulate laundry detergent composition comprising a

Abstract

The present invention relates to a particulate laundry detergent composition comprising a first optical whitening agent and a second optical whitening agent. A water soluble unit dose article comprising the particulate laundry detergent composition is also contemplated.

Description

Technical Field

[0001] The present invention relates to a granular laundry detergent composition comprising a first optical brightener and a second optical brightener. Also contemplated is a water-soluble unit dose article comprising the granular laundry detergent composition. Background Art

[0002] Optical brighteners are known and have been added to laundry detergent compositions to provide a whiteness benefit to fabrics. However, typically adding optical brighteners only provides a whiteness benefit for certain fabric types. This generally means that consumers need to separate their load of fabric items and treat different fabric types with different detergents in order to provide the best whiteness benefit for all fabric types.

[0003] Accordingly, there is a need for a laundry detergent composition that provides a whiteness benefit across a range of fabric types when the fabrics are treated singly, without a negative whiteness impact on any fabric type.

[0004] Surprisingly, it has been found that the granular laundry detergent composition according to the present invention overcomes this technical problem. Summary of the Invention

[0005] A first aspect of the present invention is a granular laundry detergent composition comprising a first optical brightener and a second optical brightener; wherein the first optical brightener is selected from brighteners having the following structures;

[0006]

[0007] or mixtures thereof,

[0008] and wherein the second optical brightener has the following structure;

[0009]

[0010] A second aspect of the present invention is a water-soluble unit dose article comprising a granular laundry detergent composition, wherein the water-soluble unit dose article comprises a water-soluble nonwoven sheet, wherein;

[0011] a. the nonwoven sheet is formed to create internal compartments and the granular laundry detergent composition is housed in the compartments; or

[0012] b. the nonwoven sheet is oriented into layers that are stacked on one another and the granular laundry detergent composition is positioned between the layers. Detailed Description

[0013] Granular laundry detergent composition

[0014] The present invention relates to a granular laundry detergent composition. The granular laundry detergent composition is understood to be a free-flowing particulate composition. Generally, the granular laundry detergent composition is a full-formulation laundry detergent composition rather than a part thereof (such as spray-dried, extruded or agglomerated granules that only form part of the laundry detergent composition). Generally, the granular laundry detergent composition comprises a plurality of chemically different granules, such as spray-dried base detergent granules and / or agglomerated base detergent granules and / or extruded base detergent granules; combining one or more, generally two or more, or five or more, or even ten or more granules selected from: surfactant granules, including surfactant agglomerates, surfactant extrudates, surfactant needles, surfactant faces, surfactant flakes; phosphate granules; zeolite granules; silicate granules, especially sodium silicate granules; carbonate granules, especially sodium carbonate granules; polymer granules, such as carboxylate polymer granules, cellulose polymer granules, starch granules, polyester granules, polyamine granules, terephthalic acid polymer granules, polyethylene glycol granules; aesthetic granules, such as colored stripes, needles, layered granules and ring granules; enzyme granules, such as protease granules, amylase granules, lipase granules, cellulase granules, mannanase granules, pectate lyase granules, xyloglucanase granules, bleaching enzyme granules and co-granules of any one of these enzymes, preferably these enzyme granules contain sodium sulfate; bleaching agent granules, such as percarbonate granules, especially coated percarbonate granules, such as percarbonate coated with carbonate, sulfate, silicate, borosilicate, or any combination thereof, perborate granules, bleach activator granules such as tetraacetylethylenediamine granules and / or alkyloxysulfonate granules, bleach catalyst granules such as transition metal catalyst granules, and / or isoquinolinium bleach catalyst granules, preformed peracid granules, especially coated preformed peracid granules; filler granules, such as sulfate granules and chloride granules; clay granules, such as montmorillonite granules and clay and siloxane granules; flocculant granules, such as polyethylene oxide granules; wax granules, such as wax agglomerates; siloxane granules, optical brightener granules; dye transfer inhibitor granules; dye fixative granules; perfume granules, such as perfume microcapsules and starch-encapsulated perfume blend granules, and pre-perfume granules, such as Schiff base reaction product granules; colorant dye granules; chelating agent granules, such as chelating agent agglomerates; and any combination thereof.

[0015] Suitable laundry detergent compositions can comprise detergent ingredients selected from the following: detergency surfactants such as anionic detergency surfactants, nonionic detergency surfactants, cationic detergency surfactants, zwitterionic detergency surfactants, and amphoteric detergency surfactants; polymers such as carboxylate polymers, soil release polymers, anti-redeposition polymers, cellulose polymers, and care polymers; bleaches such as hydrogen peroxide sources, bleach activators, bleach catalysts, and preformed peracids; optical bleaches such as zinc sulfonated phthalocyanine and / or aluminum sulfonated phthalocyanine; enzymes such as proteases, amylases, cellulases, lipases; zeolite builders; phosphate builders; adjunct builders such as citric acid and citrates; carbonates such as sodium carbonate and sodium bicarbonate; sulfates such as sodium sulfate; silicates such as sodium silicate; chloride salts such as sodium chloride; chelating agents; optical brighteners; dye transfer inhibitors; dye fixatives; fragrances; siloxanes; fabric softeners such as clays; flocculants such as polyethylene oxide; defoamers; and any combination thereof.

[0016] Suitable laundry detergent compositions can have a low buffering capacity. Such laundry detergent compositions typically have a reserve alkalinity to pH 9.5 of less than 5.0 g NaOH / 100 g. These low-buffered laundry detergent compositions typically contain a low level of carbonate.

[0017] A granular laundry detergent composition contains a first optical brightener and a second optical brightener. Without wishing to be bound by theory, the optical brighteners provide a whiteness benefit to the washed fabric.

[0018] The first optical brightener is selected from brighteners having the following structures:

[0019]

[0020]

[0021] or mixtures thereof.

[0022] The second optical brightener has the following structure:

[0023]

[0024] The weight ratio of the first optical brightener to the second optical brightener is from 8:1 to 1:8, or even from 5:1 to 1:5, or even from 3:1 to 1:3.

[0025] The first optical brightener can be present between 0.1% and 5%, or even between 0.5% and 4%, by weight of the granular laundry detergent composition.

[0026] The second optical brightener may be present in an amount between 0.01% and 5%, or even between 0.5% and 4%, by weight of the granular laundry detergent composition.

[0027] The granular laundry detergent composition may comprise a third optical brightener, wherein the third optical brightener may be present in an amount between 0.1% and 5%, or even between 0.5% and 4%, by weight of the granular laundry detergent composition, and is optionally selected from the following structures:

[0028]

[0029]

[0030] or mixtures thereof.

[0031] The granular laundry detergent composition may comprise a soil-release polymer, preferably a polyester soil-release polymer. The granular laundry detergent composition may comprise a soil-release polymer in an amount between 0.1% and 5% by weight of the granular laundry detergent composition.

[0032] Polyester soil-release polymers generally have hydrophilic segments to hydrophilize the surface of hydrophobic fibers such as polyester and nylon, and hydrophobic segments to deposit on the hydrophobic fibers and remain adhered to the hydrophobic fibers until the washing and rinsing cycles are complete, thus serving as an anchor for the hydrophilic segments. This can make the stains that appear after treatment with the detergent easier to clean in a later washing process. It is also believed that promoting soil release helps to improve or maintain the wicking properties of the fabric.

[0033] The structure of the polyester soil-release polymer can be adjusted to be suitable for different detergent or detergent additive products. The soil-release polymer can be linear, branched, or star-shaped. The soil-release polymer may also comprise a variety of charged units. Generally, when the soil-release polymer is used in combination with a detergent containing an anionic surfactant, a nonionic soil-release polymer or an anionic soil-release polymer may be particularly preferred to avoid potential negative interactions between the soil-release polymer and the anionic surfactant. The soil-release polymer may comprise a capping portion, which is particularly effective in controlling the molecular weight of the polymer or changing the physical or surface adsorption properties of the polymer.

[0034] Preferred polyester soil-release polymers include terephthalate-derived polyester polymers comprising structural unit (I), or structural unit (I) and structural unit (II):

[0035] (I)-[(OCHR 1 -CHR 2 ) a -O-OC-Ar-CO-] d

[0036] (II)-[(OCHR 3 -CHR 4 ) b -O-OC-sAr-CO-] e

[0037] wherein:

[0038] a and b are from 1 to 200;

[0039] d and e are from 1 to 50;

[0040] Ar is independently selected from 1,4-disubstituted phenylene and 1,3-disubstituted phenylene

[0041] sAr is 1,3-disubstituted phenylene substituted at the 5-position with -SO3M; wherein M is selected from Na + , Li + , K + , 1 / 2Mg 2 + , 1 / 2Ca 2+ , 1 / 3Al 3+ , ammonium, monoalkylammonium, dialkylammonium, trialkylammonium or tetraalkylammonium counterions, wherein the alkyl groups are C1-C 18 alkyl or C2-C 10 hydroxyalkyl or mixtures thereof;

[0042] R 1 、R 2 、R 3 、R 4 are independently selected from H or C1-C 18 n-alkyl or iso-alkyl; preferably selected from H or C1 alkyl.

[0043] Optionally, the polymer further comprises one or more end groups (III) derived from polyalkylene glycol monoalkyl ethers, preferably selected from the structure (III-a)

[0044] -O-[C2H4-O] c -[C3H6-O] d -[C4H8-O] e -R7 (III-a)

[0045] wherein:

[0046] R7 is a straight-chain or branched C 1-30 alkyl, C2-C 30 alkenyl or a cycloalkyl group having 5 to 9 carbon atoms, or a C8-C 30 aryl group, or a C6-C 30 arylalkyl group; preferably C1-4 an alkyl group, more preferably a methyl group; and

[0047] Based on the molar average, c, d and e are independently numbers selected from 0 to 200, where the sum of c + d + e is from 2 to 500.

[0048] Wherein the [C2H4-O], [C3H6-O] and [C4H8-O] groups of the terminal group (IV-a) can be arranged in block, alternating, periodic and / or statistical arrangements, preferably in block and / or statistical arrangements, and any one of the [C2H4-O], [C3H6-O] and [C4H8-O] groups of the terminal group (IV-a) can be connected to -R7 and / or -O. Preferably, the [C3H6-O] group is connected to -O, and -O is further connected to -OC-Ar-CO- or -OC-sAr-CO-.

[0049] Optionally, the polymer comprises one or more anionic end units (IV) and / or (V). Wherein M is a counterion selected from Na + , Li + , K + , 1 / 2Mg 2+ , 1 / 2Ca 2+ , 1 / 3Al 3+ , ammonium, monoalkylammonium, dialkylammonium, trialkylammonium or tetraalkylammonium, wherein the alkyl group is C1-C 18 alkyl or C2-C 10 hydroxyalkyl or mixtures thereof.

[0050] -O-CH2CH2-SO3M (IV)

[0051]

[0052] Optionally, the polymer may comprise crosslinked polyfunctional structural units having at least three functional groups capable of undergoing esterification reactions. The functional groups can be, for example, acid-, alcohol-, ester-, anhydride- or epoxy groups, etc.

[0053] Optionally, other dicarboxylic acids or polycarboxylic acids or their salts or their (di)alkyl esters can be used in the polyesters of the present invention, such as naphthalene-1,4-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, tetrahydrophthalic acid, trimellitic acid, diphenoxyethane-4,4'-dicarboxylic acid, diphenyl-4,4'-dicarboxylic acid, 2,5-furandicarboxylic acid, adipic acid, sebacic acid, decane-1,10-dicarboxylic acid, fumaric acid, succinic acid, 1,4-cyclohexanedicarboxylic acid, cyclohexanediacetic acid, glutaric acid, azelaic acid or their salts or their (di)alkyl esters, preferably their (C1-C4)-(di)alkyl esters, and more preferably their (di)methyl esters or mixtures thereof.

[0054] A preferred class of polyester detergency polymers are nonionic polyester detergency polymers that do not contain the above structural unit (II). Particularly preferred nonionic polyester detergency polymers have a structure according to the following formula:

[0055]

[0056] Wherein:

[0057] R5 and R6 are independently selected from H or CH3. More preferably, one of R5 and R6 is H and the other is CH3.

[0058] Based on the molar average, c and d are independently numbers selected from 0 to 200, where the sum of c + d is from 2 to 400.

[0059] More preferably, d is from 0 to 50 and c is from 1 to 200,

[0060] More preferably, d is from 1 to 10 and c is from 5 to 150,

[0061] R7 is a C1-C4 alkyl group, and more preferably a methyl group,

[0062] Based on the molar average, n is from 1 to 50.

[0063] One example of a most preferred above-described suitable terephthalate-derived nonionic detergency polymer has one of R5 and R6 as H and the other as CH3; d is 0; c is from 5 to 100, and R7 is a methyl group, and n is from 3 to 10.

[0064] Another preferred class of polyester detergency polymers are anionic polyester detergency polymers that contain the above structural unit (I) and structural unit (II). Preferably, the anionic detergency polymer further contains at least one end group selected from (III-a), (IV), and (V). More preferably, the anionic detergency polymer contains structures (I) and (II) and one or two end groups (III-a), where R 7 is a C1 alkyl group, c is from 2 to 100, preferably from 3 to 50, such as 5, 10, 15, 20.

[0065] The polyester detergent polymer can be available or converted into different forms, including powders, granules, liquids, waxes, or premixes. In some embodiments, other materials (such as water, alcohols, other solvents, salts, surfactants, etc.) are required to convert the polyester detergent polymer into the above different forms, and the weight percentage of the active detergent polymer in the powder, granule, liquid, wax, or premix ranges from 10% to 100%, such as 15%, 20%, 40%, 60%, 70%, 80%, 90%, 95%, 100%. When the detergent polymer is in the form of a liquid or a premix, the premix can be transparent or opaque, white or light yellow. The opaque premix can be used to provide an opaque appearance to the final product or a part of the final product.

[0066] The polyester can be or can not be biodegradable, and the preferred detergent polymer is readily biodegradable.

[0067] Examples of suitable detergent polymers include those supplied by Clariant series, including non-ionic detergent polymers SRN 100, SRN 170, SRN 170C, SRN 170Terra, SRN 172, SRN 240, SRN 260, SRN 260life, SRN 260SG Terra, SRN UL50, SRN 300, SRN 325; and anionic detergent polymers SRA 100, SRA 300, SRA300F. Examples of suitable detergent polymers also include those supplied by Rhodia / Solvay series of polymers, including non-ionic detergent polymers Crystal, Crystal PLUS, Crystal NAT, SRP6; and anionic detergent polymers SF-2. Other examples of commercially available detergent polymers include those supplied by WeylChem series of detergent polymers, including non-ionic detergent polymers PLN1, PLN2; and anionic detergent polymers PSA1. Other examples of commercially available detergent polymers are those supplied by Sasol polymers, such as SL, HSCB, L235M B and G82. Other suitable commercially available detergent polymers include Sorez 100 (obtained from ISP or Ashland).

[0068] The raw materials for preparing the polyester of the present invention can be based on fossil carbon or renewable carbon. Renewable carbon includes carbon derived from biomass, carbon capture, or chemical recycling. Preferably, the raw materials for preparing the polyester of the present invention are at least partially based on renewable carbon. The renewable carbon index (RCI, a measure of sustainability by dividing the number of carbons from renewable sources by the total number of carbons in the active ingredient) of the polyester of the present invention is preferably higher than 40%, more preferably higher than 50%, even more preferably higher than 60%, particularly preferably 70% to 100% (including 100%), and most preferably 100%.

[0069] The granular laundry detergent composition may contain a color - toning dye. The color - toning dye may be selected from Direct Violet 9, Direct Violet 66, Direct Violet 99, Acid Violet 50, Solvent Violet 13, or a combination thereof. The granular laundry detergent composition may contain a color - toning dye in an amount between 0.1% and 10% by weight of the granular laundry detergent composition.

[0070] The color - toning dye may have the following structure;

[0071]

[0072] Wherein: R1 and R2 are independently selected from: H; alkyl; alkoxy; alkyleneoxy; alkyl - capped alkyleneoxy; urea; and amide groups; R3 is a substituted aryl group; X is a substituent comprising a sulfonamide moiety and optionally an alkyl and / or aryl moiety, and wherein said substituent comprises at least one alkyleneoxy chain, said at least one alkyleneoxy chain comprising at least four alkyleneoxy moieties with an average molar distribution.

[0073] The color - toning dye may have the following structure:

[0074]

[0075] Where the index values x and y are independently selected from 1 to 10.

[0076] The first optical brightener and the second optical brightener may be located in the same particle or in separate particles.

[0077] The granular laundry detergent composition may contain spray - dried particles, agglomerates, extrudates, flakes, or mixtures thereof.

[0078] Generally, suitable spray - drying methods include the steps of forming an aqueous slurry mixture, transferring the aqueous slurry mixture to a pressure nozzle by at least one pump, preferably two pumps. Atomizing the aqueous slurry mixture into a spray - drying tower and drying the aqueous slurry mixture to form spray - dried particles. Preferably, the spray - drying tower is a counter - current spray - drying tower, although a co - current spray - drying tower may also be suitable.

[0079] Typically, the spray-dried powder is subjected to cooling, such as stripping. Typically, the spray-dried powder is subjected to size classification, such as sieving, to obtain the desired particle size distribution. Preferably, the spray-dried powder has a particle size distribution such that the weight average particle size is in the range of 300 microns to 500 microns, and less than 10% by weight of the spray-dried particles have a particle size greater than 2360 microns.

[0080] It may be preferable to heat the aqueous slurry mixture to raise the temperature before atomizing into the spray drying tower.

[0081] For anionic surfactants, such as linear alkylbenzene sulfonates, it may be preferable to be introduced into the spray drying process after the step of forming the aqueous slurry mixture: for example, after pumping, the acid precursor is introduced into the aqueous slurry mixture.

[0082] For gases, such as air, it may be preferable to be introduced into the spray drying process after the step of forming the aqueous slurry.

[0083] For any inorganic components, such as sodium sulfate and sodium carbonate, it may be preferable to be micronized into small particle sizes if present in the aqueous slurry mixture.

[0084] Typically, suitable agglomeration methods include the step of contacting a detergent component, such as a detergent surfactant, for example linear alkylbenzene sulfonate (LAS) and / or alkyl alkoxylated sulfate, with an inorganic material, such as sodium carbonate and / or silica, in a mixer. The agglomeration method may also be an in-situ neutralization agglomeration method, in which an acid precursor of the detergent surfactant, such as LAS, contacts a basic material, such as a carbonate and / or sodium hydroxide, in a mixer, and in which the acid precursor of the detergent surfactant is neutralized by the basic material during the agglomeration method to form the detergent surfactant.

[0085] Other suitable detergent components that can be agglomerated include polymers, chelating agents, bleach activators, siloxanes, and any combination thereof.

[0086] The agglomeration method can be a high, medium, or low shear agglomeration method, in which a high shear, medium shear, or low shear mixer is used accordingly. The agglomeration method can be a multi-step agglomeration method, in which two or more mixers are used, such as a combination of a high shear mixer and a medium or low shear mixer. The agglomeration method can be a continuous method or a batch method.

[0087] It may be preferable for the agglomerates to be subjected to a drying step, for example, subjected to a fluidized bed drying step. It may also be preferable for the agglomerates to be subjected to a cooling step, for example, subjected to a fluidized bed cooling step.

[0088] Typically, the agglomerates are subjected to size classification, such as fluidized bed elutriation and / or screening, to obtain the desired particle size distribution. Preferably, the agglomerates have a particle size distribution such that the weight average particle size is in the range of 300 microns to 800 microns, and less than 10% by weight of the agglomerates have a particle size less than 150 microns, and less than 10% by weight of the agglomerates have a particle size greater than 1200 microns.

[0089] It may be preferred for the small and oversized agglomerates to be recycled back into the agglomeration process. Typically, the oversized particles are subjected to a comminution step, such as grinding, and recycled back to an appropriate location in the agglomeration process, such as a mixer. Typically, the fines are recycled back to an appropriate location in the agglomeration process, such as a mixer.

[0090] For ingredients, such as polymers and / or nonionic detergent surfactants and / or fragrances, it may be preferred to spray them onto the substrate detergent particles, such as spray-dried substrate detergent particles and / or agglomerated substrate detergent particles. Typically, this spraying step is carried out in a tumbling drum mixer.

[0091] The granular laundry detergent composition may be contained within a package, where the package comprises a cellulose-containing material, a plastic, or a mixture thereof, preferably where the package comprises at least 50% recycled material by weight of the package. Preferably, the cellulose-containing material includes cardboard, corrugated cardboard, paperboard, or a mixture thereof.

[0092] Method for washing fabrics

[0093] A method of washing a fabric includes the steps of contacting a solid composition with water to form a wash liquid, and washing the fabric in the wash liquid. Typically, the wash liquid has a temperature above 0 °C to 90 °C, or to 60 °C, or to 40 °C, or to 30 °C, or to 20 °C. The fabric may be contacted with water before, after, or simultaneously with contacting the solid composition with water. Typically, the wash liquid is formed by contacting the laundry detergent with water in an amount such that the concentration of the laundry detergent composition in the wash liquid is 0.2 g / l to 20 g / l, or 0.5 g / l to 10 g / l, or to 5.0 g / l. The method of washing the fabric may be carried out in a front-loading automatic washing machine, a top-loading automatic washing machine, including a high-efficiency automatic washing machine, or a suitable hand-washing container. Typically, the wash liquid contains 90 liters or less, or 60 liters or less, or 15 liters or less, or 10 liters or less of water. Typically, 200 g or less, or 150 g or less, or 100 g or less, or 50 g or less of the laundry detergent composition is contacted with water to form the wash liquid.

[0094] Water-soluble unit-dose product

[0095] Another aspect of the present invention is a water-soluble unit dose article that comprises a particulate laundry detergent composition. The water-soluble unit dose article includes a water-soluble nonwoven sheet, wherein;

[0096] a. The nonwoven sheet is formed to create internal compartments, and the particulate laundry detergent composition is housed within the compartments;

[0097] Or

[0098] b. The nonwoven sheet is oriented into layers that are stacked on one another, and the particulate laundry detergent composition is positioned between the layers.

[0099] The water-soluble fibrous nonwoven sheet comprises a plurality of fibers. Preferably, the fibers are entangled fibers in the form of a fibrous structure.

[0100] The water-soluble fibrous nonwoven sheet can be uniform or can be layered. If layered, the water-soluble fibrous nonwoven sheet can include at least two and / or at least three and / or at least four and / or at least five layers.

[0101] Preferably, the water-soluble fibrous nonwoven sheet has a basis weight between 20 gsm and 60 gsm, preferably between 20 gsm and 55 gsm, more preferably between 25 gsm and 50 gsm, and most preferably between 25 gsm and 45 gsm. Those skilled in the art will know the method of measuring the basis weight.

[0102] As used herein, "fiber" refers to an elongated element having a length that exceeds its average diameter, preferably a ratio of length to average diameter of at least about 10.

[0103] Preferably, each fiber can have a length greater than or equal to 5.08 cm, greater than or equal to 7.62 cm, greater than or equal to 10.16 cm, greater than or equal to 15.24 cm, or a mixture thereof.

[0104] Alternatively, each fiber can have a length less than 5.08 cm, less than 3.81 cm, less than 2.54 cm, or a mixture thereof.

[0105] Each fiber can have a width less than 100 μm, less than 75 μm, less than 50 μm, less than 25 μm, less than 10 μm, less than 5 μm, less than 1 μm, or a mixture thereof. Those skilled in the art will know the standard methods and techniques for measuring width. Preferred methods include scanning electron microscopy (SEM) or optical microscopy and image analysis software.

[0106] The water-soluble fiber nonwoven sheet may comprise a plurality of fibers that are the same or substantially the same in compositional angle. Alternatively, the water-soluble fiber nonwoven sheet may comprise two or more different fibers according to the present invention. Non-limiting examples of fiber differences may be physical differences such as differences in diameter, length, texture, shape, hardness, elasticity, etc.; chemical differences such as crosslinking level, solubility, melting point, Tg, active agent.

[0107] Preferably, the fibers are present in an amount between 80% and 95% by weight of the water-soluble fiber nonwoven sheet, preferably between 85% and 93% by weight, more preferably between 87% and 90% by weight.

[0108] The water-soluble fiber nonwoven sheet may exhibit different regions, such as regions of different basis weights, densities, and / or thicknesses. The water-soluble fiber nonwoven sheet may comprise a texture on one or more of its surfaces. The surface of the water-soluble fiber nonwoven sheet may comprise a pattern, such as a non-random repeating pattern.

[0109] The water-soluble fiber nonwoven sheet may have a thickness between 0.01 mm and 100 mm, preferably between 0.05 mm and 50 mm, more preferably between 0.1 mm and 20 mm, even more preferably between 0.1 mm and 10 mm, even more preferably between 0.1 mm and 5 mm, even more preferably between 0.1 mm and 2 mm, even more preferably between 0.1 mm and 0.5 mm, and most preferably between 0.1 mm and 0.3 mm. Those skilled in the art will know the standard methods for measuring thickness.

[0110] The fibers may comprise a polyvinyl alcohol polymer. Preferably, the fibers comprise between 50% and 98% by weight of the fiber, preferably between 65% and 97% by weight, more preferably between 80% and 96% by weight, even more preferably between 88% and 96% by weight of polyvinyl alcohol.

[0111] The polyvinyl alcohol polymer may have a weight average molecular weight between 50 kDa and 150 kDa, preferably between 75 kDa and 140 kDa, more preferably between 100 kDa and 130 kDa. As used herein, "weight average molecular weight" means the weight average molecular weight determined using gel permeation chromatography according to the protocol set forth in Colloids and Surfaces A. Physico Chemical & Engineering Aspects, Volume 162, 2000, pages 107-121. Those skilled in the art will know other known techniques for determining the weight average molecular weight (MW).

[0112] Preferably, the polyvinyl alcohol polymer is a polyvinyl alcohol homopolymer. Preferably, the polyvinyl alcohol homopolymer has an average degree of hydrolysis percentage of 75% to 100%, preferably 80% to 95%, and most preferably 85% to 90%. Preferably, the polyvinyl alcohol homopolymer has an average viscosity of 1 mPas to 30 mPas, preferably 5 mPas to 25 mPas, and most preferably 10 mPas to 20 mPa, where the viscosity is measured in a 4% aqueous solution in demineralized water at 20 μ.

[0113] The fiber preferably contains a breaker between 0.1% and 15% by weight of the fiber, where the breaker is selected from polyols, sugar alcohols, amines, amides, carbohydrates, polyvalent cations, or mixtures thereof, preferably selected from polyols, sugar alcohols, or mixtures thereof. Preferably, the fiber contains a breaker between 1% and 12% by weight of the fiber, preferably between 2% and 10%.

[0114] The dimensions and values disclosed herein should not be construed as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to represent the recited value and a range functionally equivalent thereto. For example, a dimension disclosed as "40 mm" is intended to represent "about 40 mm".

[0115] Unless expressly excluded or otherwise limited, each document cited herein, including any cross-referenced or related patent or patent application and any patent application or patent to which this application claims priority or the benefit of its filing date, is hereby incorporated by reference in its entirety. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein, or an admission that it alone, or in any combination with any one or more other references, teaches, suggests, or discloses any such invention. Further, when any meaning or definition of a term in this invention conflicts with the same term's meaning or definition in a document incorporated by reference, the meaning or definition assigned to the term in this invention shall govern.

[0116] Although specific embodiments of the invention have been illustrated and described, it will be apparent to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, it is intended that all such changes and modifications that fall within the scope of the invention be covered by the appended claims.

[0117] Examples

[0118] The following experiments were conducted;

[0119] 1) Preparation of test compositions

[0120] Use a granular detergent with the following composition as the basic detergent, and this preparation does not contain optical brighteners. The components and contents in the preparation are as follows:

[0121] Formulation ％ Linear alkylbenzene sulfonate 8.67 HG650 0.52 Sodium silicate 5.33 Sodium carbonate 12.13 HEDP 0.26 Sodium sulfate 41.87 Zeolite 1.34 Defoamer (GD6) 0.32 MGDA 0.51 Sodium percarbonate 7 Carboxymethyl cellulose 0.18 Tetraacetylethylenediamine (TAED) 1.65 Enzymes (protease / mannanase / lipase / amylase) 1.00 Alcohol ethoxylate (7EO) 0.98 Sodium chloride Balance

[0122] Prepare 8 separate washing solutions using water with a hardness of 7 US grains / gallon, containing 5 g / L of the above preparation for each washing cycle.

[0123] The following table shows the amounts of different optical brighteners (expressed as ppm active substance) added to each washing solution to evaluate the fabric whiteness performance of each sample:

[0124]

[0125] Optical brightener structure :

[0126]

[0127] 2) Test fabrics

[0128] Whiteness tracer

[0129] 5x5 cm polyester fabric samples (supplied by Centre for Test Materials, Vlaardingen, Netherlands). 4 replicates are used for each test preparation.

[0130] Ballast

[0131] 5x5 cm knitted cotton ballast (supplied by Warwick Equest, Consett, United Kingdom), with a total load weight of 60 g.

[0132] Soil

[0133] 5x5 cm SBL2004 scale samples (supplied by Centre for Test Materials, Vlaardingen, Netherlands). 21 samples are used for each test preparation.

[0134] 3) Test washing procedures

[0135] 1. The method involves using an oscillating detergent tester to simulate the action of a washing machine.

[0136] 2. The test preparation is used to wash the white tracer fabric together with the knitted cotton ballast, and the test preparation is added to maintain a water:clothes ratio of 17:1.

[0137] 3. Place the oscillating detergent meter can containing the test solution (1.0 L) plus the test fabric in a water bath at 35 °C

[0138] and stir at 250 rpm for 30 minutes. After washing, then rinse the test fabric and the ballast in fresh water (at 15 °C, 7.0 US gPg hardness) for 5 minutes, rinsing a total of 2 times.

[0139] 4. Repeat the washing process using the multi-cycle test fabric from the first washing cycle for 3 more washing cycles.

[0140] 5. Then remove the tracer replica and dry at ambient room temperature for > 12 hours. Measure the whiteness level of the test fabric using a spectrophotometer (D65 lamp) to show the whiteness performance of each example.

[0141] 4) Comparison

[0142] Evaluate the whiteness performance of the examples in Table 1 according to the whiteness method shown above. As shown in Table 1, when fluorescent brightener 185 is combined with C.I. fluorescent brightener 260 (Example E), a significant synergistic effect is shown. A +8.1 increase in WCIE is shown relative to the reference formulation (Example A), and this beneficial effect is greater than the beneficial effects of the additives of the individual technologies in Examples B and C.

[0143] Table 1 - Whiteness properties of fluorescent brightener 185 and C.I. fluorescent brightener 260

[0144]

[0145] Evaluate the whiteness performance of the examples in Table 2 according to the whiteness method shown above. As shown in Table 2, when fluorescent brightener 185 is combined with C.I. fluorescent brightener 351 (Example F), a significant synergistic effect is shown. A +9.7 increase in WCIE is shown relative to the reference formulation (Example A), and this beneficial effect is greater than the increase in WCIE of the beneficial effects of the additives of the individual technologies in Examples B and D.

[0146] Table 2 - Whiteness properties of fluorescent brightener 185 and C.I. fluorescent brightener 351

[0147]

[0148] Evaluate the whiteness performance of the examples in Table 3 according to the whiteness method shown above. When fluorescent brightener 185 is combined with C.I. fluorescent brightener 260 and C.I. fluorescent brightener 351 (Example H), no significant synergistic effect is shown. The increase in WCIE of +5.2 WCIE relative to the reference formulation (Example A) is less than the increase in WCIE of the beneficial effects of the additives of the individual technologies in Examples B and G.

[0149] Table 3 - Whiteness properties of fluorescent brightener 185 and C.I. fluorescent brightener 260 + 351

[0150]

Claims

1. A granular laundry detergent composition comprising a first optical brightener and a second optical brightener; Wherein the first optical brightener is selected from brighteners having the following structure: or a mixture thereof, And among them, The second optical brightener has the following structure:

2. A granular laundry detergent composition according to claim 1 wherein the weight ratio of the first optical brightener to the second optical brightener is from 8:1 to 1:8, or even from 5:1 to 1:5, or even from 3:1 to 1:

3.

3. A granular laundry detergent composition according to any preceding claim, wherein the first optical brightener is present at between 0.1% and 5%, or even between 0.5% and 4%, by weight of the granular laundry detergent composition.

4. A granular laundry detergent composition according to any preceding claim wherein the second optical brightener is present at between 0.01% and 5%, or even between 0.5% and 4%, by weight of the granular laundry detergent composition.

5. A granular laundry detergent composition according to any preceding claim, wherein the granular laundry detergent composition comprises a third optical brightener selected from the following structures: or a mixture thereof.

6. A granular laundry detergent composition according to any preceding claim, wherein the granular laundry detergent composition comprises a surfactant, wherein the surfactant is selected from anionic surfactants, nonionic surfactants or mixtures thereof.

7. A granular laundry detergent composition according to claim 6, wherein the anionic surfactant comprises linear alkylbenzene sulfonate, ethoxylated alkyl sulfate, alkyl sulfate or mixtures thereof, preferably wherein the granular laundry detergent composition comprises between 5% and 60% of the anionic surfactant by weight of the granular laundry detergent composition.

8. A granular laundry detergent composition according to claim 6 or 7, wherein the nonionic surfactant is a fatty alcohol ethoxylate, preferably wherein the granular laundry detergent composition comprises between 0.1% and 40% by weight of the granular laundry detergent composition of said fatty alcohol ethoxylate.

9. A granular laundry detergent composition according to any preceding claim comprising a soil release polymer, preferably a polyester soil release polymer, wherein preferably the granular laundry detergent composition comprises between 0.1% and 5% of said soil release polymer by weight of the granular laundry detergent composition.

10. A granular laundry detergent composition according to any preceding claim comprising a hueing dye.

11. A granular laundry detergent composition according to claim 10 comprising at least 0.1% by weight of the granular laundry detergent composition and 10% of said hueing dye.

12. A granular laundry detergent composition according to any preceding claim, wherein the granular laundry detergent composition comprises spray-dried granules, agglomerates, extrudates, tablets or mixtures thereof.

13. A granular laundry detergent composition according to any preceding claim, wherein the first optical brightener and the second optical brightener are located in the same granule or in separate granules.

14. A granular laundry detergent composition according to any preceding claim, wherein the granular laundry detergent is contained within a package, wherein the package comprises a cellulose-containing material, a plastic or a mixture thereof, preferably wherein the package comprises at least 50% recycled material by weight of the package.

15. A water-soluble unit dose article comprising a granular laundry detergent composition according to any preceding claim, wherein the water-soluble unit dose article comprises a water-soluble nonwoven sheet, wherein; a. The nonwoven sheet is formed to produce an internal compartment, and the granular laundry detergent composition is contained in the compartment; or b. The nonwoven sheet is oriented into layers, the layers are stacked on top of each other, and the granular laundry detergent composition is positioned between the layers.

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