MXPA99010346A - Sprayed granule - Google Patents

Abstract

A detergent composition comprises detergent particles, each particle having a substantially anhydrous coating comprisinga fluorescent whitening agent and a nonionic surfactant. A process for the preparation of the said detergent composition comprises spraying base detergent particles with a substantially anhydrous mixture comprising the fluorescent whitening agent and the nonionic surfactant.

Description

SPRAY GRANULATION FIELD OF THE INVENTION The present invention relates to a new detergent composition and to a process for preparing the same, and in particular to the provision of a laundry detergent composition having improved whiteness as perceived by the consumer.

BACKGROUND OF THE INVENTION The use of bleaching agents, or brighteners, in laundry applications for bleaching fabrics has been widespread since the mid-1970s. Since then, much research has been carried out as to the properties of such bleaching agents, and many different compositions. which include such agents have been described in the literature. However, most bleaching agent applications have been for fabric bleaching objects, rather than for bleaching the detergent composition itself. WO 94/05761 discloses a process for preparing a high density granular detergent composition in which the bulk density of the detergent composition is increased by spraying detergent particles with a liquid and then powdering with a fine powder in a rotating drum or mixer. It is preferred that the liquid consists of a nonionic surfactant. Optionally, the liquid may also include other ingredients, such as perfume or a slurry, in water, of an optical brightener. The examples describe the use of a 20% aqueous solution of optical brightener. However, a problem in mixing a nonionic surfactant with water is that this can lead to the formation of nonionic surfactant flakes which tend to block the spray nozzle, thereby interrupting the process and requiring cleaning of the nozzle before the process can be restarted. Additionally, the use of an aqueous spray tends to be detrimental to the stability of the final detergent composition because the water tends to react with and / or promote the reaction of the components of the composition. JP-A-07286198 discloses a process for preparing a granular nonionic detergent composition which consists in spray-drying detergent particles containing 1% by weight of a nonionic surfactant and 0.01% by weight of a brightener. The brightener is first dissolved and / or dispersed in the nonionic surfactant, and then granulated with other ingredients to form detergent particles before spray drying. The procedure is designed to avoid fluorescence de-uniformity of textile articles during washing.

BRIEF DESCRIPTION OF THE INVENTION According to a first aspect of the present invention, a detergent composition consists of detergent particles, each particle having a substantially anhydrous coating consisting of a fluorescent whitening agent and a nonionic surfactant. The composition of the present invention has improved bleaching properties, even with very low levels of bleaching agent, compared to a composition in which the bleaching agent is present through the detergent particles, as described in JP-A-0728198, discussed above. According to a second aspect of the present invention, a process for preparing a detergent composition comprises spraying detergent particles with one. substantially anhydrous mixture comprising a fluorescent whitening agent and a non-surface active agent Ionic Because the method of the present invention substantially excludes the presence of water during the spray of the bleaching agent / nonionic surfactant mixture, it overcomes two major problems experienced in the prior art when non-ionic surfactant is sprayed when It is wet. In addition, a dramatic increase in the whiteness of the resulting product is observed.

According to a third aspect of the present invention, the use of a substantially anhydrous mixture consisting of a fluorescent whitening agent and a nonionic surfactant improves the whiteness properties of detergent particles, when the detergent particles are sprayed with said mixture.

DESCRIPTION OF THE INVENTION Prior to spraying the detergent particles, a substantially anhydrous mixture of bleaching agent and nonionic surfactant is prepared by dispersing or partially dissolving the bleaching agent in the nonionic surfactant, preferably mixing to achieve a substantially homogeneous mixture. The homogeneity of the mixture can be measured using, for example, a UV lamp, thereby determining the uniformity of fluorescence. The temperature at which the bleaching agent and the non-ionic surfactant are mixed is selected so as not to damage any of those components. Typically, however, the temperature will be on the 25-80 ° C scale, and preferably -60 ° C. In the context of the present application, by substantially anhydrous means that the amount of water present in the bleaching agent / nonionic surfactant mixture is less than 5% by weight of that mixture, preferably less than 3% by weight, and more preferably less than 1% by weight. More preferably, the mixture should not contain added water above that included in the commercially available forms of the bleaching agent and the nonionic surfactant. For example, some nonionic surfactants may include about 0.5% by weight of water. The ratio of bleaching agent: nonionic surfactant included in the mixture to be sprayed onto the detergent particles will depend, in part, on the nature of the bleaching agent and the nonionic surfactant, and also on the nature of the final product in the composition. which coated particles are going to be incorporated. Generally, however, the ratio of bleaching agent: nonionic surfactant will be in the range of 1: 500 to 1: 5, and typically 1: 400 to 1: 10, by weight. It may be preferred to use a bleaching agent: nonionic surfactant ratio of from 1:75 to 1: 200 by weight for compact products, a ratio of 1: 150 to 1: 400 by weight for "big box" products, and a ratio from 1: 5 to 1: 50 by weight for individual detergent additives, for example in the form of agglomerates, capsules, or exudates. The bleaching agent is preferably a biphenyl distyril compound, such as disodium 4,4 * -bis (2-sulfostyril) biphenyl, otherwise known as Brightener 49 or Tinopal CBS (trademark, supplied by Ciba Geigy), or a coumarin compound, such as Tinopal SWN (trade name, supplied by Ciba Geigy). However, other bleaching agents known in the art may also be suitable for use in the present invention, including benzide sulfone disulfonic acids (BS), naphthotriazortinylbenzenesulphonic acids (NTSA), amino coumarins (AC) and diphenylpyrazolines (DP) and derivatives thereof. the same. Any suitable nonionic surfactant, or mixture of nonionic surfactants, can be used, provided that it is capable of forming a substantially homogeneous dispersion, or solution, with the bleaching agent. For example, suitable nonionic surfactants include water-soluble condensation products of aliphatic alcohols having 8 to 22 carbon atoms, either straight or branched in configuration, and which are optionally ethoxylated, for example 3 to 100. moles of ethylene oxide per mole of alcohol. Preferred are the condensation products of alcohols having from 9 to 15 carbon atoms, with 3 to 80 moles of ethylene oxide per mole of alcohol. Typically, the amount of the bleach / nonionic surfactant mixture sprayed onto the detergent particles will be from 0.1 to 10%, preferably 0.2 to 5% by weight of the total particle weight. This means that the amount of bleaching agent present can be as low as 0.01% by weight, and still provide beneficial results in relation to the whiteness of the composition. The base detergent particles themselves, ie the particles on which the mixture of bleaching agent / nonionic surfactant is sprayed, can consist of any suitable detergent components. For example, the detergent particles may consist of surfactants selected from anionic, sutionionic, ampholytic and cationic, and mixtures thereof. The detergent particles may also consist of a nonionic surfactant, which may be the same as or different from the nonionic surfactant used to coat those particles. Suitable examples of such surfactants include any of those described in WO-A-9405761. The base detergent particles may also include a bleaching agent, which may be the same as or different from the bleaching agent used to coat the particles. Any conventional bleaching agent is suitable for this purpose. The base detergent particles may also include a builder, which may be selected from conventional builders for use in laundry detergents. Suitable examples include alumino silicate ion exchange materials, neutral or alkaline salts, inorganic phosphate builders, non-phosphorus organic builders and polymeric builders, and any of the builders described in WO-A- 9405761. Other ingredients commonly used in detergent compositions may also be included in the compositions of the present invention. Examples of such ingredients are described in WO-A-9405761.

The base detergent particles can be prepared by any known method. For example, in one method each component is matched by weight on a movable band, and then mixed together in a rotating drum or mixer to agglomerate the separated components. In another method, a number of highly active pastes, typically at least 40% by weight of active, are agglomerated, for example as described in any of EP-A-0508543, EP-A-0578872, EP-A-0618289 and EP-A-0663439. In yet another method, the detergent particles can be prepared by forming a slurry of the individual components, and then spray drying the slurry to produce a "blown powder". The preparation method used will generally depend on the final form of the required product, and the final product may contain particles prepared by a number of different methods. The bleaching agent / nonionic surfactant mixture can be sprayed onto the base detergent particles by any convetional spray means. For example, a Loedige CB mixer can be used. The speed at which the mixture is sprayed onto the detergent particles will vary according to the spray method, but will typically be on the scale of 0.5 to 5 tonnes / hr for a commercial process. After the detergent particles have been sprayed with the bleach / nonionic surfactant mixture they may be slightly tacky in nature. In this case, it may be preferred to powder the detergent particles with a processing aid, typically in the form of a fine powder having a particle size of up to 100 μm, but generally up to 10 μm, such as zeolite, silica, clay, carbonate or starch. , or any other suitable material. The final coated detergent particles can be used as a detergent composition by themselves, for example if each particle consists of a mixture of detergent components or if the composition consists of deferent particles consisting of different detergent components. Alternatively, or additionally, the coated detergent particles may be mixed with other particulate detergent materials, as conventionally used in the laundry field. The present invention is further illustrated by the following Examples, in which, when not stated otherwise, all amounts are given in% by weight of the total composition, and the abbreviations used have the following meanings: LAS: alkyl linear sodium benzene sulfonate of C? _? 3. TAS: sodium alkyl sulphate of wood bait. CxyAS: sodium alkyl sulfate of C? X-C? Y. C46SAS: (2,3) C alqu4-C16 secondary sodium alkyl sulfate. CxyEzS: sodium alkyl sulphate of C? X-C-? And condensed with z moles of ethylene oxide. CxyEz: predominantly linear primary alcohol of C - ?? - C? And condensed with an average of z moles of ethylene oxide.

QAS: R2.N + (CH3) 2 (C2H4? H) with R2 = C8-C14. Soap: linear sodium alkyl carboxylate derived from an 80/20 mixture of wood and coconut fatty acids. CFAA: (coconut) C-12-C14 alkyl N-methyl glucamide. TFAA: alkyl N-methyl glucamide of C-iß-C-is-TPKFA: fatty acids of whole cut enriches of C12-Ci4. STPP: anhydrous sodium tripolyphosphate. TSPP: tetrasodium pyrophosphate. Zeolite A: hydrated sodium aluminosilicate of formula Nai2 (A102SiO2) i2-27l-l2? which has a main particle size on the scale of 0.1 to 10 μm (weight expressed on an anhydrous basis). NaSKS-6: crystalline layered silicate of formula Na2Si2O5. Citric acid: anhydrous citric acid. Borate: sodium borate. Carbonate: anhydrous sodium carbonate with a particle size between 200μm and 900μm. Bicarbonate: anhydrous sodium bicarbonate with a particle size distribution between 400μm and 1200μm. Silicate: amorphous sodium silicate (SiO: Na2O = 2.0: 1). Sulfate: anhydrous sodium sulfate. Citrate: activity trisodium citrate dihydrate of 86.4% with a particle size distribution between 425μm and 850μm.

MA / AA: copolymer of 1: 4 maleic acid / acrylic, average molecular weight of about 70,000. AA: sodium polyacrylate polymer of average molecular weight 4,500. CMC: sodium carboxymethyl cellulose. Cellulose ether: methyl cellulose ether with a degree of polymerization of 650 available from Shin Etsu Chemicals. Protease: proteolytic enzyme of activity 4KNPU / g sold by NOVO Industries A / S under the trade name Savinase. Alcalase: proteolytic enzyme of activity 3AU / g sold by NOVO Indrustries A / S. Cellulase: activity cellulitic enzyme 1000 CEVU / g sold by NOVO Industries A / S under the trade name Carezime. Amylase: amylolytic enzyme of activity 120 KNU / g sold by NOVO Industries A / S under the trade name Termamyl 120T. Lipase: lipolytic enzyme of activity 100KLU / g sold by NOVO Industries A S under the trade name Lipolase. Endolase: activity endoglucanase enzyme 3000 CEVU / g sold by NOVO Industries A / S. PB4: sodium perborate tetrahydrate of nominal formula PB1: anhydrous sodium perborate bleach of nominal formula NaBO2.H2O2.

Percarbonate: sodium percarbonate of nominal formula 2Na2C? 3.3H2? 2. NOBS: nonanoyloxybenzene sulfonate in the form of the sodium salt. NAC-OBS: (6-nonamidocaproyl) oxybenzene sulfonate. TAED: tetraacetylethylenediamine. DTPA: diethylene triamine pentaacetic acid. DTPMP: diethylene triamine penta (methylene phosphonate), marketed by Monsanto under the trade name Dequest 2060. EDDS: isomer of ethylenediamine-N 'disuccinic acid (S, S) - in the form of its sodium salt. Activated photo bleach: sulfonated zinc phthalocyanine encapsulated in soluble polymer in dextrin. Lipid 1: 4,4'-bis (2, sulfostyril) biphenyl of Disodium. Brightener 2: 4,4'-bis (4-anilino-6-morpholino-1, 3,5-triazin-2-yl) amino stilbene-2,2'-disulfonate of Disodium. HEDP: 1, 1-hydroxyethane diphosphonic acid. PEGx: polyethylene glycol, with a molecular weight of x. PEO: polyethylene oxide, with an average molecular weight of 50,000. TEPAE: ethoxylated tetraethylenepentamine. PVP: Polyvinylpyrrolidone polymer with an average molecular weight of 60,000. PVNO: polyvinylpyridine N-oxide polymer, with an average molecular weight of 50,000.

PVPVI: copolymer of polyvinylpyrrolidone and vinylimidazole, with an average molecular weight of 20,000. QEA: bis [(C2H5?) (C2H4?) N] CH3-N + -C6H12-N + (CH3) bis [(C2H5O) - (C2H4?) N) where n = 20-30. SRP1: sulfobenzoyl and esters blocked with oxy oxyethylene and terephthaloyl base structure. SRP2: short block polymer of poly (1, 2-propylene terephthalate) diethoxylate. Anti silicone foam: polydimethylsiloxane foam controller with siloxane-oxyalkylene copolymer as a dispersing agent with a ratio of said foam controller to said dispersing agent from 10: 1 to 100: 1. Wax: paraffin wax. Lift: perfume.

EXAMPLES EXAMPLE 1 A slurry was prepared by mixing anionic surfactant paste (s) together with inorganic materials and minor detergents at a final moisture content of 20-35% by weight. The slurry was then spray-dried using a spray-drying tower to produce a "blown powder". To a 3 m 3 mixing vessel, agitated with a paddle stirrer and having a recirculation line, the nonionic surfactant (s) was added. To this nonionic surfactant was added powdered brightener at a rate of 5 kg / minute to ensure uniform dispersion of the brightener in the nonionic. This mixture was left stirring for 30 minutes at a temperature of 35-60 ° C, depending on the non-ionic used, to ensure complete dispersion of the brightener. At the end of this period a small sample of the obtained solution / dispersion was taken and measured under a UV lamp for uniform fluorescence, and therefore a uniform distribution of the brightener. The nonionic / brightener dispersion was then pumped into a Loedige CB 30 mixer. It entered the Loedige mixer at a rate of 2 tons / hr through a 5mm opening. At the same end of the Loedige mixer a stream of the spray-dried powder was intimately mixed with the non-ionic / brightener stream. The resulting mixture exited through the opposite end of the Loedige mixer. Any other additives to be sprayed, for example perfume, were sprayed separately. The finished powder, coated, was then mixed with other dry detergent additives.

The formulations in tables 1 to 3 were prepared in this way. TABLE 1 The above detergent formulations are of particular utility under conditions of European washing machine. TABLE 2 Formulations E and F are of particular utility under washing machine conditions of the United States. G is particularly useful under conditions of Japanese washing machine.

TABLE 3 The above granular detergent compositions are of particular utility under European washing conditions.

EXAMPLE 2 A blown, coated powder was prepared as described in the example, and mixed with agglomerates of anionic surfactant and other dry detergent additives. Agglomerates of anionic surfactant were produced as described in Example 1 of EP-A-0663439, forming highly active anionic pastes, for example about 80% active, and mixing those in a twin screw extruder with silicate and polymer if present. I presented. The mixture was then passed to a Loedige CB mixer where it was mixed with a stream of zeolite and carbonate powder if present. The irregularly shaped particles were allowed to fall under gravity onto a Loedige KM mixer where they were rounded and polished with zeolite. The particles were then passed to a fluid bed dryer, to remove excess water if present. The formulations in Table 4 were prepared in this way. Formulation J is particularly suitable for use under conditions of Japanese washing machine. The K to O formulations are particularly suitable for use under washing machine conditions of the United States.

CTMDRO 4 EXAMPLE 3 A mixture of agent (s) -non-ionic surfactant / brightener was prepared as described in Example 1. The agglomerates of anionic surfactant, prepared as described in Example 2, and yellows in color, were then added as a stream Free continuous to a horizontal drum mixer, at a rate of 3 tons / hr. The nonionic / brightener mixture was sprayed through two fluid nozzles onto the agglomerate near the inlet to a mixer at a rate of 30 kg / hr. The zeolite was then blown onto the agglomerates through a tube near the outlet of the mixer. The resulting coated agglomerates were white and were mixed with a blown powder, produced according to example 1, and other dry detergent additives. The formulations shown in Tables 5 and 6 were prepared in this way. The detergent formulations that do not contain bleach from table 6 are of particular use in the washing of colored garments.

TABLE 5 TABLE 6 EXAMPLE 4 A mixture of nonionic surfactant / brightener was prepared as described in Example 1, in which the nonionic surfactant used was C25E3 and the ratio of brightener powder to nonionic surfactant was about 3: 100, in weigh. A mixture of detergent materials was prepared by dosing the remaining dry additives detailed in Table 7 below, as supplied, on a movable web from weight loss feeders. This mixture was then fed to a tilting rotary drum mixer at a delivery rate of 30 tons / hr. The non-ionic / brightener mixture was sprayed through a two fluid nozzle onto the particle bed at a rate of 1.5 tons / hr. The particles were then sprayed with perfume before leaving the drum. The resulting slightly sticky particles were then passed to a mixer Loedige KM where they were polished with zeolite at 2 tons / hr TABLE 7 The above high density granular laundry detergent compositions V to AA are of particular utility under European washing machine conditions.

EXAMPLE 5 Three compact detergent powders, powders I to III in Table 8 below, were prepared according to the method described in Example 1 of EP-A-0663439, except that when the powder III was prepared a mixture of non-ionic surfactant C45AE7 and brightener 1 (produced according to example 1 above) were sprayed onto the final compact powder. Powder I is the current Ariel Futur product of the Applicant, and is for reference only. The powder II, also only for reference, and the powder III, according to the present invention, have the same composition as the powder I except that they do not contain non-white components, in order to more easily observe the beneficial effects of the present invention.

The whiteness of each of the powders I to III was measured using a Hunterlab Color / Difference model D25-2 meter before dusting the powders with zeolite, and the obtained measurements applied using two different correlations for whiteness, defined as W1 and W2 as right away. W1 = L-3b, by Hunter W2 = L + 3a-3b, by Stensby. The results are shown in Table 9 below.

TABLE 9 The comparison of values VV1 and W2 illustrates that the powder III, according to the present invention, has improved whiteness compared to powder II, without considering the correlation used. In addition, the value b measured for the powder III was considerably lower than that for the powder II, demonstrating that the powder III was much less yellow.

Claims (10)

1. NOVELTY OF THE INVENTION CLAIMS 1. - A detergent composition consisting of detergent particles, each particle having a substantially anhydrous coating consisting of a fluorescent whitening agent and a nonionic surfactant.
2. 2. A composition according to claim 1, wherein the ratio of bleaching agent: nonionic surfactant is in the range of 1: 500 to 1: 5, by weight.
3. 3. A composition according to claim 1 or claim 2, wherein the bleaching agent is a biphenyl distyryl compound or a coumarin compound.
4. 4. A composition according to claim 3, wherein the bleaching agent is 4,4'bis (2-sulfostyril) biphenyl disodium.
5. 5. A composition according to any preceding claim, wherein the nonionic surfactant is a soluble condensation product is water of an aliphatic alcohol having 8 to 22 carbon atoms, optionally ethoxylated.
6. 6. A composition according to any of the preceding claims, wherein the detergent particles contain a bleaching agent, optionally of a different type to the bleaching agent included in the coating.
7. 7. A composition according to any of the preceding claims, wherein the detergent particles each have an additional outer coating consisting of a substantially anhydrous powder.
8. 8. A process for preparing a detergent composition consisting of spraying detergent particles with a substantially anhydrous mixture consisting of a fluorescent whitening agent and a nonionic surfactant.
9. 9. A method according to claim 8, wherein the ratio of bleaching agent: nonionic surfactant is defined in claim 2.
10. 10. A method according to claim 8 or claim 9, wherein the bleaching agent is defined in claim 3. 1 - A method according to any of claims 8 to 10, wherein the nonionic surfactant is defined in claim 4. 12. A method according to any of claims 8 to 11, wherein prior to spraying the bleaching agent is dispersed or dissolved in the nonionic surfactant. 13. - A method according to claim 12, wherein the dispersion or dissolution is carried out at a temperature in the range of 25-80 ° C. 14. A process according to any of claims 8 to 13, wherein the detergent particles have been made by spray drying. 15. A process according to any of claims 8 to 13, wherein the detergent particles have been made by agglomeration. 16. A method according to any of claims 8 to 15, further comprising that after spraying the detergent particles, the detergent particles are powder-coated. 17. A detergent composition obtainable by a process according to any of claims 8 to 16. 18. The use of a substantially anhydrous mixture consisting of a fluorescent whitening agent and a nonionic surfactant to improve the properties of whiteness of detergent particles, spraying the detergent particles with said mixture.