MXPA00008244A - Process for preparing granular detergent compositions - Google Patents

Abstract

A process for preparing a granular detergent composition with improved wash-delivery properties comprises a first step of preparing a liquid component containing an anionic surfactant, a nonionic surfactant and a structurant and a second step comprising admixture of the liquid component with a solid component in a granulator. An optional third step comprises drying and/or cooling. The structurant is incorporated in an amount such that the liquid component is pumpable at temperatures of 50°C or more but causes sufficient solidification to form a free-flowing granulated product. In bleach-containing products, the process also provides for reduced fabric dye damage in the wash.

Description

PROCESS FOR PREPARING GRANULAR DETERGENT COMPOSITIONS FIELD OF THE INVENTION The present invention relates to the preparation of a granular detergent composition, or component containing anionic and nonionic surfactants, by mixing and granulating liquid and solid components, preferably continuously. The invention is especially applicable to the production of granular compositions containing zeolite as a builder.

BACKGROUND OF THE INVENTION The production of detergent powders by spray drying has been known for a long time in the art, with spray dried products which generally provide good powder supply characteristics such as supply and dissolution. However, the spray drying process is expensive in terms of capital and energy, and the result is an expensive product. Accordingly, the detergent industry seeks methods for producing powders which are more cost effective and which produce higher bulk density powders as compared to the conventionally available spray drying.

In recent years there has been much interest in the production of detergent products by processes which mainly use mixing, without the use of spray drying. In this type of process, the various components are mixed dry and optionally granulated with a liquid binder. The liquid binders typically used in such granulation processes are nonionic surfactants, anionic surfactants, acid precursors of anionic surfactants or any mixture thereof. Utilizing these granulation processes, detergent powders having a high bulk density, typically from 700 to 900 g / 1, have been produced. A problem that occurs with the concentrated powders of high bulk density is a slow or incomplete dissolution in the wash liquor, which leads to undissolved product residues, usually white, in the fabrics subjected to the laundry process. For example, it is known that concentrated powders containing zeolite have the problem that powders containing undissolved zeolite are trapped in the fabric fiber; This manifests as white spots, clearly visible and unpleasant to the eye. In addition to the undesirability of undissolved residues in the fabric, undissolved powder containing bleaches trapped in the fabric fiber can lead to a damage in fabric color, generally known as a stain damage.

We have found that in the case of detergent compositions containing both anionic and nonionic surfactants, prepared by mixing liquid components with solid particulate components in a mixer / granulator, the level of residues and the color damage of the fabric can be significantly reduced. washing by premixing the anionic and nonionic surfactants to form a structured combination prior to the granulation process.

PREVIOUS TECHNIQUE EP 420 317 (Unilever) describes a process for the continuous preparation of granular detergent compositions or components having a higher density than that obtainable in spray drying processes. The process consists of three stages, an agglomeration in a high-speed mixer, a densification in a moderate-speed granulator densifier whereby the material is carried or maintained in a deformable state, and the drying or cooling of the product, or both things (for example in a fluid bed). The liquid binder in the agglomeration step is a liquid acid precursor of an anionic surfactant, which is neutralized in situ by a water-soluble, solid, inorganic alkaline material (eg, sodium carbonate) in the high-speed mixer. EP 544 365 (Unilever) describes a process for the preparation of a granular composition of highly active alkyl sulfate in the same equipment described in EP 420 317, or alternatively in a batch granulation. In this case, a mixture of a sodium or potassium salt of an alkyl sulfate, for example a primary alkyl sulfate (PAS) and an alkoxylated nonionic surfactant is used as the liquid phase for the granulation in the high speed mixer. . In order to obtain a product with good powder properties, the viscosity of the liquid phase can be increased by adding one or more components such as, for example, water and soap. The increased viscosity seems to provide more control over the agglomeration process. EP 265 203 (Unilever) describes mobile liquid surfactant compositions at 20-80 ° C which contain sodium or potassium salts in an alkylbenzene sulfonate or alkyl sulfate, an ethoxylated nonionic surfactant and water, the amount of water does not exceed 10% by weight. Such liquid surfactant compositions can be sprayed into a solid particulate absorbent material, for example, a porous, spray-dried base powder, having a low bulk density, and containing little or no active substance, to form a powder. detergent base that has an increased bulk density. Document 436 240 (Unilever) discloses mobile liquid surfactant compositions at a temperature within the range of 20-80 ° C consisting essentially of those components described in EP 265 203 and further a fatty acid. The liquid surfactant compositions are dispersed over solid, phosphate-free particulate absorbent materials, such as spray-dried zeolite or layered silicates, to produce detergent compositions having bulk densities of at least 500 g / 1 and having improved supply properties . There is no teaching regarding the agglomeration of the solid material in a mixer / granulator, only the absorption of the liquid surfactant within the solid material in a rotating drum apparatus. EP 507 402 (Unilever) discloses a process for preparing a liquid surfactant composition comprising an anionic surfactant, a non-ionic surfactant and having a relatively low water content, in which essentially equimolar amounts of neutralizing agent are combined simultaneously and liquid acid precursor of the anionic surfactant, with the nonionic surfactant. It is especially preferred that the process be carried out continuously in a cycle reactor. The liquid surfactant compositions may additionally contain a fatty acid, and may be applied in a process for making granular detergent compositions with a high bulk density having a high level of active detergent, as described by EP 367 339 (Unilever). The unpublished international patent application No. PCT / EP97 / 04749 (which has a priority date of 09/10/96) describes a process for providing improved granularity for powders produced by an inflation process and containing sodium tripolyphosphate (STP) or another solid that has a low capacity to transport liquids or low hydratable properties, or both. The process of the document PCT / EP97 / 04749 also provides additional benefits for detergent builders such as zeolites, which allow the manufacture of granular products with a lower relative humidity, without drying compared to previously available ones. These low levels of humidity allow percarbonate bleaches to be dosed later, and these are preferred over perborates with fundamentals in environmental problems. According to the process described in PCT / EP97 / 04749, a liquid component of the detergent is formulated with a structurant so that it remains pumpable at the temperature at which the liquid component is formed and then mixed with a solid component at a lower temperature to which the structuring causes the solidification of the mixture. There is no disclosure in PCT / EP97 / 04749 of the dissolution properties of the powders produced by the claimed process or of the levels of residues or damage by bleach in the wash.

BRIEF DESCRIPTION OF THE INVENTION We have surprisingly found that the powders produced following the claimed process in PCT / EP97 / 04749 have, in addition to good granularity, greatly improved washing supply properties. Therefore, according to a first aspect, the present invention provides the use of a process for preparing a granular detergent composition with improved washing supply properties, the process comprising the steps of: (i) preparing a liquid component comprising an anionic surfactant or a precursor thereof, a nonionic surfactant and a structuring agent; (ii) mixing the liquid component with a solid component in a high speed mixer / granulator; and optionally (i) drying and / or cooling, the structurant is incorporated in an amount such that the liquid component is pumpable at temperatures of 50 ° C or higher (eg 60 ° C or higher) but causes sufficient solidification during the second or third stages to form a granular product that flows freely.

The granular detergent compositions according to the invention can be in the form of complete products ready for sale to the consumer. Alternatively, they can be formulated as base powders or adjuvants for mixing with other ingredients such as, for example, a bleaching system, to form final detergent products. Accordingly, in a second aspect, the present invention provides the use of a process in the preparation of a detergent product containing bleach, the detergent product produces less damage to the dyes in the wash, the process comprises the steps defined in the first appearance. The invention is particularly applicable to powders containing zeolite as a builder. However, this also applies to powders containing other builder materials such as, for example, STP, citrates and carbonates. In a third aspect, the invention provides a granular detergent composition or component with improved dissolution properties, which can be obtained by the process defined in the first aspect, the granular detergent composition comprising an anionic surfactant, a nonionic surfactant, soap and crystalline or amorphous aluminosilicate, or both, as a builder.

The present invention is particularly applicable to powders containing an alkylbenzene sulfonate as the anionic surfactant. In a fourth aspect, the present invention provides a process for preparing a granular detergent composition, the process comprising the steps of: (i) preparing a liquid component comprising a surfactant and a structuring agent, the structuring agent is incorporated in an amount such that the liquid component is pumpable at temperatures of 50 ° C or greater but which causes sufficient solidification during the second or third stages, to form a granular product that flows freely; (ii) mixing the liquid component with a solid component in a high speed mixer / granulator; and optionally (iii) drying or cooling, or both, wherein the surfactant comprises an anionic surfactant or a precursor thereof and a nonionic surfactant, the solid component comprises an aluminosilicate and by means of which the granular detergent composition has an decay rate greater than 25 μms "1.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES The supply to the wash can be determined by measuring the particular properties inherent in the detergent powder as is well known to those skilled in the art. These include, for example, solubility, dissolution and disintegration, all of which can be measured by well-known methods that are presented in the literature. For example, solubility can be measured in a "insoluble" fractions test. In a typical test of insoluble fractions, a sample of the powder (for example 10 g) is stirred in water (for example 500 ml) for 2 minutes at a suitable temperature. The mixture is then filtered through a screen and any residual powder is dried and weighed. The disintegration rate is another parameter by which the supply to the wash can be evaluated. The disintegration process involves both the decomposition of the particulate material into smaller pieces as well as the dissolution of the particulate material in the solution. The rate of disintegration of the powder particles in the present invention is measured using a laser diffraction technique. For example, about 30 particles of a particular size range (for example between 500 and 710 μm) are placed in a bucket which is filled with a sodium carbonate solution 0.1 w / w%. The laser then records the average particle size of the powder during disintegration. The decay rate is then taken as the average rate of decrease in the average particle diameter from the start of the measurement until the particles have dissolved to less than 50 μm in diameter. The granular detergent compositions of the invention typically have a disintegration rate greater than 25 μms "1, preferably greater than 50 μms" 1, and much more preferably / greater than 75 μms "1. In contrast to the measurement properties inherent in the powders added to the wash, the actual washing results can be evaluated by determining the powder's supply properties, for example, the level of pulverized residues in the washed fabrics can be measured.The granular product prepared in this way can be consider that it flows freely if it has a dynamic flow rate (DFR) greater than 90 mis "1. Conveniently, DFR can be measured by a technique whereby a known volume of powder is allowed to flow through a calibrated orifice and a tube. The flow time between the two light sensors is automatically recorded and the DFR is calculated with the known volume and the recorded flow time. The granular detergent compositions according to the invention may have a bulk density of 550 g / 1, more preferably at least 650 g / 1. However, these products can also be produced with lower apparent densities. The resulting granular products of the invention, when subjected to tabletting, produce tablets having a high degree of hardness measured by the breaking strength (Pmax) and the E-module (Emod). Preferred embodiments of the processes and compositions according to the present invention can be characterized by the strength and modulus E of a sample of: (a) a tabletted composition produced by the process; and / or (b) a tablet formed by cooling the liquid component until solidified, or both. The resistance measurement (hardness) can be obtained using an Instron pressure device. The powder is subjected to tabletting in a punch and die to form a tablet 9 mm in diameter and 16 mm in height, formed by exerting a maximum pressure of 10 tons on the surface of the tablet. In the case of a solidified liquid component taken from the process before it makes contact with the solid component, the diameter of the tablet is 14 mm and its height is 19 mm. The tablet (pulverized or liquid component) is destroyed between a fixed plate and a mobile one. The speed of the moving plate is set to 5 mm / min, which causes a measuring time of approximately 2 seconds. The pressure curve is recorded in a computer. Therefore, the maximum pressure is provided (at the time of tablet rupture) and the E module is calculated from the slope. For the granular product, the minimum value of Pmax is preferably 0.5 M Pa, more preferably 2 M Pa, and the minimum Emod value is preferably 20 M Pa, more preferably 50 M Pa. However, for the solidified liquid component, Pmax at 20 ° C is preferably a minimum of 0.2 M Pa, for example, from 0.3 to 0.5 M Pa. At 55 ° C, a typical range is 0.05 to 0.25 M Pa. At 20 ° C, Emod for the liquid combination preferably is a minimum of 3 M Pa, for example 5 to 10 M Pa. The liquid component is preferably prepared in a dynamic shear mixer for premixing the components thereof and any neutralization of anionic acid precursor is performed . The dynamic mixer is preferably located in a circuit with a heat exchange to remove heat from the reaction of such neutralization. In the context of the present invention, the term "structuring" means any component which allows the liquid component to obtain solidification in the granulator and therefore a good granulation, even if the solid component has a low liquid transport capacity. The structurants can be classified as those that are considered to exert their structuring (solidifying) effect by one of the following mechanisms, specifically: recrystallization (for example silicate or phosphate); creation of a network of finely divided solid particles (for example silicas or clays); and those which exert their steric effects at the molecular level (for example soaps or polymers) such as those types commonly used as builders. One or more structurants can be used. Soaps represent a preferred class of structurant, especially when the liquid component comprises a liquid nonionic surfactant. In many cases, it may be desirable for the soap to have an average chain length greater than the average chain length of the liquid nonionic surfactant, but less than twice the average chain length of the latter. If desired, the solid components can be dissolved or dispersed in the liquid component. Typical amounts of ingredients in the essential liquid component such as% by weight of the liquid component are the following: preferably from 10% to 98% by weight of the nonionic surfactant, more preferably from 30% to 70% by weight, and especially from 40% to 50% by weight; preferably, from 98% to 10% by weight of anionic surfactant, more preferably from 70% to 30%, and especially from 5Q% to 40% by weight; preferably, from 2% to 30% by weight of structurant, more preferably from 5% to 20%, and even more preferably from 5% to 15% by weight, and especially from 10% to 15% by weight. In addition to the anionic surfactant or precursor thereof, the nonionic surfactant and the structuring agent, the liquid component may also contain other organic solvents. The liquid component is also preferably substantially non-aqueous. That is, the total amount of water therein is not more than 15% by weight of the liquid component, preferably not greater than 10% by weight, typically from 5% to 8% and especially from 6% to 7%. Typically, from 3% to 4% by weight of the liquid component can be water as the reaction by-product, and the rest of the water present will be the solvent in which the alkaline material dissolves. The liquid component most preferably lacks all the water in addition to that of the sources mentioned above, except perhaps for amounts / impurities. It is further preferred to form part or all of the anionic surfactant in situ in the liquid component by reaction of an appropriate acid precursor and an alkaline material such as an alkali metal hydroxide, for example NaOH. Since the latter mnormally be dosed as an aqueous solution, it is inevitable that a little water is incorporated. In addition, the reaction of an alkali metal hydroxide and an acid precursor also provides a little water as a by-product. However, in principle, any inorganic material can be used for neutralization, but water-soluble alkaline inorganic materials are preferred. Another preferred material is sodium carbonate, either alone or in combination with one or more inorganic water-soluble materials, for example sodium bicarbonate or silicate. As mentioned in the foregoing, sodium carbonate can provide the alkalinity necessary for the washing process, but can additionally serve as a builder. In this case, the invention can be used advantageously for the preparation of detergent powders in which the sodium carbonate is the sole or main builder. Then, substantially more carbonate will be present than is required for the neutralization reaction with the anionic acid surfactant precursor. The liquid component may optionally comprise the dissolved solids and / or the finely divided solids which are dispersed therein. The only limitation is that with or without dissolved or dispersed solids, the liquid component must be pumpable at temperatures of 50 ° C or higher or at any rate, 60 ° C or higher, for example 75 ° C. Preferably it is solid below 50 ° C, preferably at 25 ° C or less. A definition of solid can be found in the Handbook of Chemistry and Physics, CRC Press, Boca Raton, Florida, sixty-seventh edition, 1986. Generally, pumpable liquid components have a viscosity not greater than 1 Pas at the cutting rate pumping. Typically, the pump cut-off rate will be greater than 1 s "1. The structurants cause solidification in the liquid component preferably to produce a combination and tablet strength as described above. 10 ° C, preferably greater than 20 ° C below the temperature at which the combination is prepared and pumped into the granulator If the solid component comprises or consists substantially of an aluminosilicate builder, the weight ratio of the The liquid component relative to the solid component when the two are contacted for mixing, is preferably 0.4: 1 to 0.7: 1. If the solid component comprises or consists substantially of a phosphate builder, this ratio is preferably 0.25: 1 to 0.5: 1. Suitable anionic surfactants are well known to those skilled in the art. incorporation in the liquid phase include alkylbenzene sulfonates, particularly linear alkylbenzene sulphonates having an alkyl chain length of C -C-C15 / secondary and primary alkyl sulphates, particularly C12-C15 primary alkyl sulfates; alkyl ether sulfates; olefin sulfonates; alkylxylene sulfonates; dialkyl sulfosuccinates; and fatty acid ester sulfonates. Sodium salts are generally preferred. The nonionic surfactant component of the liquid phase can be any one or more nonionic liquids that are selected from ethoxylates of primary and secondary alcohols, especially C8-C20 aliphatic alcohols ethoxylated with an average of 1 to 20 moles of ethylene per mole of alcohol, and more especially the primary and secondary C10-C15 aliphatic alcohols ethoxylated with an average of 1 to 10 moles of ethylene oxide per mole of alcohol. Non-ethoxylated nonionic surfactants include alkyl polyglycosides, glycerol monoethers and polyhydroxyamides (glucamide). The liquid acid precursor can be selected from linear alkylbenzenesulfonic acids (LAS), alpha-olefin sulfonic acids, internal olefin sulfonic acids, sulfonic acid fatty acid esters and combinations thereof. The process of the invention is especially useful for producing compositions comprising alkylbenzene sulphonates by reaction of the corresponding alkylbenzene sulfonic acid, for example Shell dobanoic acid. The linear or branched primary alkyl sulphates (PAS) have 10 to 15 carbon atoms and can also be used.

The solid component with which the liquid phase is mixed preferably comprises a builder. The total amount of builder in the final compositions suitably is from 10 to 80% by weight, preferably from 15 to 60% by weight. The builder may be present in an adjuvant with other components or, if desired, separate builder particles containing one or more builder materials may be used. The present invention is especially applicable for use wherein the solid component comprises builders which are selected from crystalline and amorphous aluminosilicates, for example zeolites as described in GB-A-1 473 201; amorphous aluminosilicates as described in GB-A-1 473 202; and mixed crystalline / amorphous aluminosilicates as described in GB 1 470 250; and layered silicates as described in EP-B-164 514. The aluminosilicates may suitably be present in a total amount of 10 to 60% by weight, and preferably in an amount of 15 to 50% by weight. The zeolite used in most of the commercial particulate detergent compositions is zeolite A. However, advantageously, the maximum aluminum P zeolite can be used (zeolite MAP) described and claimed in EP-A-384 070. The zeolite MAP is an aluminosilicate alkali metal of the type P having a silicone to aluminum ratio not exceeding 1.33, preferably not exceeding 1.15 and more preferably not exceeding 1.07. Other suitable builders include hydratable salts, preferably in substantial amounts such as at least 25% by weight of the solid component, preferably at least 10% by weight. Hydratable solids include inorganic sulfates and carbonates as well as inorganic phosphate builders, for example sodium orthophosphate, pyrophosphate and tripolyphosphate. Other inorganic builders that may be present include sodium carbonate (as mentioned above, an example of a hydratable solid), if desired in combination with a crystallization seed for calcium carbonates, as described in GB-A- 1 437 950. As mentioned above, such sodium carbonate may be the residue of an inorganic alkaline neutralizing agent used to form a non-ionic structuring agent in situ. Organic builders that may be present include polycarboxylate polymers such as polyacrylates, acrylic / maleic copolymers and acrylic phosphinates; monomeric polycarboxylates such as citrates, gluconates, oxydisuccinates, glycerol mono-, di- and trisuccinates, carboxymethyloxysuccinates, carboxymethyloxy alkaloates, dipicolinates, hydroxyethyliminodiacetates, aminopolycarboxylates such as nitrilotriacetates (NTA), ethylenediaminetetraacetates (EDTA) and iminodiacetates, alkyl- and alkenylmalonates and succinates; and sulfonated fatty acid salts. A copolymer of maleic acid, acrylic acid and vinyl acetate is especially preferred since it is biodegradable and therefore environmentally desirable. This list is not intended to be exhaustive. Especially preferred organic builders are citrates, suitably used in amounts of 5 to 30% by weight, preferably 10 to 25% by weight; and acrylic polymers, more especially acrylic / maleic copolymers, suitably used in amounts of 0.5 to 15% by weight, preferably 1 to 10% by weight. The detergency builder is preferably present in the form of alkali metal salt, especially sodium salt. In addition to the nonionic and anionic surfactants of the liquid component the granular detergent compositions of the invention may contain one or more active detergent compounds (surfactants) which may be chosen from soap active detergents and non-anionic soap detergents., cationic, nonionic, amphoteric and zwitterionic, and mixtures thereof. These can be dosed at any appropriate stage before or during the process. Many suitable active detergent compounds are available and are fully described in the literature, for example, in "Surface-Active Agents and Detergents", Volumes I and II, by Schwartz, Perry and Berch. The preferred active detergent compounds that can be used are soaps and synthetic non-soap, anionic and non-ionic compounds. The detergent compositions according to the invention may also contain a bleach system, desirably a peroxy bleach compound, for example an inorganic persalt an organic peroxyacid capable of providing hydrogen peroxide in aqueous solution. The peroxy bleach compound can be used in conjunction with a bleach activator (bleach precursor) to improve the bleach action at low wash temperatures. An especially preferred bleach system comprises a peroxy bleach compound (preferably sodium percarbonate optionally together with a bleach activator) and a transition metal bleach catalyst as described and claimed in EP-A-458 397 and EP-A-509 787 Usually, any bleach and other sensitive ingredients, such as enzymes and perfumes, are added later, after granulation, together with other minor ingredients. Typical minor ingredients include sodium silicate; corrosion inhibitors including silicates; agents that prevent the position network such as cellulosic polymers; fluorescent substances; inorganic salts such as sodium sulfate, foaming control agents, foaming reinforcers as appropriate; proteolytic and lipolytic enzymes; colorants; colorful spots; perfumes; foam controllers; and fabric softening compounds. This list is not intended to be exhaustive. The flow of the powder can be improved by the incorporation of a small amount of an additional powdered structurant, for example a fatty acid (or a fatty acid soap), a sugar, an acrylate or an acrylate / maleate polymer, a silicate of sodium, which is suitably present in an amount of 1 to 5% by weight. With respect to the equipment used for the process mixing step (ie, after the combination of the ingredients in the liquid component), the liquid component is preferably mixed with the solid components in a first mixing step in a mixer / densifier of high speed to form a granular detergent material. Optionally, the granular detergent material of the first mixing stage can subsequently be treated in a second mixing step in a moderate speed grater / densifier. If a product of high apparent density is desired, in this stage it can be carried or maintained in the required deformable state. In any case, the product of the first stage or of mixing or of the second stage of mixing is then cooled or dried, or both. The residence time in the high-speed mixer / densifier in the first preferable mixing step is from about 5 to 30 seconds. The residence time in the moderate speed mixer / densifier during any second (optional) mixing step is preferably about 1 to 10 minutes. It is preferred to perform any such process as a continuous process but it can be carried out as a batch process, in a high shear or low shear mode. In the first mixing step, the solid components of the raw material are mixed thoroughly with the liquid combination by means of a high speed mixer / densifier. Such a mixer provides a high energy stirring inlet and achieves deep mixing in a very short time. Advantageously we have used a high speed mixer / densifier like the Lódige type (trademark) CB 30 Recycler. This apparatus consists essentially of a large and static hollow cylinder having a diameter of approximately 30 cm which is placed horizontally. In the middle part it has a rotating rod with different types of blades mounted on it. It can rotate at speeds between 100 and 2500 rpm, depending on the degree of densification and the particle size that is desired. The blades in the rod provide a deep mixing action of solids and liquids, which can be mixed at this stage. The average residence time depends to some extent on the rotational speed of the rod, the position of the blades and the weir in the outlet opening. Other types of high speed mixers / densifiers having a comparable effect on detergent powders are also contemplated. For example, a Shugi (trademark) or Drais (trademark) K-TTP 80 granulator can be used. In the first mixing step, the raw material components are carefully mixed in a high speed mixer / densifier during a relatively Joxeve time of about 5-30 seconds, preferably under conditions by which the initial material is put into, or maintained in a deformable state, which is to be defined later. In the case of production of high bulk density products after the first mixing stage, if the resulting detergent material still has considerable porosity, then instead of choosing a longer residence time in the high speed mixer / densifier to obtain an increase in the additional bulk density, then it can be subjected to a second optional mixing step in which the detergent material is, treat for 1-10 minutes, preferably for 2-5 minutes, in a moderate speed / densifier granulator. During this second processing step, the conditions are such that the powder is placed in, or maintained within a deformable state. As a consequence, the particle porosity will be further reduced. The main differences in the first stage lie in the lower mixing speed and the longer residence time of 1-10 minutes, and the need for the powder to be deformable. The second optional mixing step can be carried out successfully in a Lódige (trademark) KM 300 mixer, also known as Lódige Ploughshare. This apparatus consists essentially of a hollow static cylinder having a rotating rod in the middle part. In this rod, various blades are mounted in the form of a plow. It can be rotated at a speed of 40-160 rpm. Optionally, cutters of a much higher speed can be used to avoid excessive agglomeration. Another suitable machine for this stage is, for example, the Drais (brand name) KT 160 equipment. However, instead of using a high speed densifying / densifying machine, followed by a separate, moderate speed densifying mixing machine, the The same effect can be obtained using a single machine operated at two speeds. It can be operated first at a high speed for mixing / densification, and then at a moderate speed for granulation / densification. Suitable machines include mixers of the FuJaeMR FS-G series; from the DiosnaMR V series by Dierks and Sohne, Germany; Pharma MatrixTM from T.K. Fielder Ltd; England; the Fuji ™ VG-C series from Fuji Sangyo Co., Japan; Roto machine "" by Zanchetta & Co. srl, Italy and the SchugiMR Flexomix granulator. For use, handling and storage, the densified detergent powder may be in a free-flowing state. Therefore, in a final stage, the powder can be dried or cooled, or both, if necessary. This step can be carried out in a known manner, for example in a fluid bed apparatus (drying, cooling) or in air raising (cooling). It is advantageous if the powder only needs one cooling step, because the required equipment is relatively simple and more economical. For the production of high bulk density products, any optional second mixing step, and preferably in addition to the first mixing step, the detergent powder must be put into a deformable state in order to obtain optimum densification. The high speed mixer / densifier or the moderate speed granulator / densifier, or both, are then able to effectively deform the particulate material in such a way that the particle porosity is considerably reduced or maintained at a low level, and consequently the apparent density increases. The invention will be explained in more detail below by means of the following non-limiting examples. EXAMPLES Preparation of detergent powders Powders having the following composition are prepared: The base powders are prepared by formulating the liquid component, mixing the liquid component with the solid components in a continuous Lodige recycler and a high speed mixer / granulator for about 10 seconds, transferring the material to a moderate speed mixer / granulator Lodige Ploughshare is mixed for about 3 minutes, and finally it is dried and cooled which provides the resulting material in a fluid bed to produce the granular base powder.

In the comparative example A, the liquid components are added as two separate mixtures, the liquid combinations (a) and (a1) / the granulator. The combination (a) consists of Na-LAS and a combination of LAS acid, while the combination (a ') consists of a non-ionic surfactant and a fatty acid. The acid LAS and the fatty acid of combinations (a) and (a ') respectively, are neutralized to their respective sodium salts by sodium carbonate in the recycler. In Example 1, the liquid component is added as a single mixture. The LAS acid, the fatty acid, the nonionic surfactant and NaOH are combined in a cycle reactor to produce a liquid combination consisting of Na-LAS, non-ionic surfactant, soap and water. The soap in the liquid component acts as a structuring agent. This combination is then mixed with the solid material in the Lodige Recycler.

Levels of residue and damage in the color of the fabric, in the wash 39 pieces of black fabric made of different fibers and 9 pieces sensitive to fabric bleach are placed in a washing machine. 75 g of washing powder are metered in through a hatch and a short wash cycle of 25 minutes at 30 ° C is carried out. After three rinses, the pieces of cloth are dried and classified visually.

The incidence of residues and damage to the dye is recorded (Table 2). The residue levels are determined in three scales. Patches, particles and films. Dye damage is determined on a three point scale as low, medium or high intensity. A rating of 5 on the scale of the patches means that on average 5 of the 48 pieces show patches after washing. In addition, the total number of pieces that exhibited at least one residue or one point of dye damage are counted.

It can be seen clearly that, by following the process of the invention, as in Example 1, a greater than 50% reduction in the levels of residue and damage to the dye in the wash is obtained, in comparison with Comparative Example A, in where structuring is not present in the liquid component.

Claims (18)

1. The use of a granular detergent composition having bleach to reduce less damage to dye in the wash, the composition is prepared by a process comprising the steps of: (i) preparing a liquid component comprising an anionic surfactant or a precursor thereof, a nonionic surfactant and a structuring agent; (ii) mixing the liquid component with a solid component in a high speed mixer / granulator; and optionally (iii) drying or cooling, or both, the structurant which is incorporated in an amount such that the liquid component is pumpable at temperatures of 50 ° C or higher (eg 60 ° C or higher) but causes sufficient solidification during the second or third, stages, or both, to form a granular product that flows freely.

2. The use of a granular detergent composition to improve the washing supply properties, the composition is prepared by a process comprising the steps of: (i) preparing a liquid component comprising an anionic surfactant or a precursor thereof, a non-surfactant, ionic and a structuring; (ii) mixing the liquid component with a solid component in a high speed mixer / granulator; and optionally (iii) drying or cooling, or both, the structurant which is incorporated in an amount such that the liquid component is pumpable at temperatures of 50 ° C or higher (eg 60 ° C or higher) but causes sufficient solidification during the second or third stages, or both, to form a granular product that flows freely.

3. The use of a process, as described in claim 1 or 2, wherein the liquid component is pumpable at a temperature of 60 ° C or higher, preferably 75 ° C or more. 10 major.

4. The use of a process, as described in any of the preceding claims, wherein the liquid component is solid below 50 ° C, preferably 15 to 25 ° C or less.

5. The use of a process, as described in any of the preceding claims, wherein the liquid component solidifies to form a tablet, which 20 20 ° C, has a Pmax value of at least 0.2 M Pa, preferably 0.3 to 0.5 M Pa or an Emod value of at least 3 M Pa, preferably 5 to 10 M Pa, or both.

6. The use of a process, as described in any of the preceding claims, wherein the anionic surfactant is an alkylbenzene sulfonate.

7. The use of a process, as described in any of the preceding claims, wherein the liquid component is substantially non-aqueous.

8. The use of a process, as described in claim 7, wherein the liquid component contains at most 15% by weight of water.

9. The use of a process, as described in any of the preceding claims, wherein the granular detergent composition can be formed in a tablet having a Pmax value of at least 0.5 M Pa or an Emod value of at least 20 M Pa, or both.

10. The use of a process, as described in any of the preceding claims, wherein the solid component comprises a builder material.

11. The use of a process, as described in claim 10, wherein the builder material comprises an aluminosilicate builder material.

12. The use of a process, as described in any of the preceding claims, wherein the liquid component contains from 10% to 98% by weight of the liquid component of the nonionic surfactant.

13. The use of a process, as described in any of the preceding claims, wherein the liquid component contains from 98% to 10% by weight of the liquid component of anionic surfactant.

14. The use of a process, as described in any of the preceding claims, wherein the liquid component contains up to 30% by weight of the liquid or structuring component.

15. The use of a process, as described in any of the preceding claims, wherein the weight ratio of the liquid component to the solid component is from 0.4: 1 to 0.7: 1.

16. A process for preparing a granular detergent composition, the process comprises the steps of: (i) preparing a liquid component comprising a surfactant and a structurant, the structurant is incorporated in an amount such that the liquid component is pumpable at temperatures of 50 ° C or greater but causes sufficient solidification during the second or third stages, or both, to form a granular product that flows freely; (ii) mixing the liquid component with a solid component in a high speed mixer / granulator; and optionally (iii) drying or cooling, or both, wherein the surfactant comprises an anionic surfactant or a precursor thereof and a nonionic surfactant, the solid component comprises an aluminosilicate and wherein the granular detergent composition has a disintegration rate greater than 25 μms "1.

17. The granular detergent composition with improved dissolution properties, obtainable by the process defined in the first aspect, the granular detergent composition comprises an anionic surfactant, a nonionic surfactant, soap and an aluminosilicate builder.

18. The granular detergent composition, as described in claim 17, wherein the anionic surfactant is an alkylbenzene sulfonate.