EP0488868B1 - Alcaline metal silicate based builder for detergent compositions - Google Patents

Abstract

Builder agent for powdered detergent composition, consisting of an alkali metal silicate rich in silicon atoms in the Q2 and Q3 form. A solution of alkali metal silicate with an SiO2/M2O ratio of 1.6 to 3.5 which, as such, has a solids content of 10 - 60 % or which is in supported form, especially in the form of cogranulates, the weight ratio of silicate expressed on dry basis/water associated with the silicate ranging from 100/120 to 100/40, is an example of a silicate rich in silicon atoms in the Q2 and Q3 form. Use in powdered detergent compositions, especially for a washing machine and for a dishwasher.

Description

The subject of the present invention is a "builder" agent consisting of alkali metal silicates rich in species in which the silicon atoms are in Q₂ and Q₃ form, intended for detergent compositions, in particular for powdered detergents, in particular for washing machines or for dishwasher.

The term "builder" is understood to mean any active adjuvant which improves the performance of the surfactants of a detergent composition.

The builder must have a so-called "softening" effect on the water used for washing. It must therefore eliminate the calcium and magnesium which are present in the water in the form of soluble salts, and in the stains of the linen in more or less soluble complex forms. The elimination of calcium and magnesium can be done either by complexation, in the form of soluble species, or by ion exchange, or by precipitation. If precipitation is involved, this must be checked to avoid encrustation on the laundry or the elements of washing machines.

This precipitation control is in particular obtained by water-soluble polymers having an affinity for calcium and magnesium.

It is also necessary that the builder adds to the emulsifying effect of surfactants vis-à-vis fatty stains, a dispersing effect vis-à-vis "pigmentary" stains such as metal oxides, clays, silica, various dusts, humus, limestone, soot ...

This dispersing effect is generally obtained thanks to the presence of polyanions, providing a high density of negative charges at the interfaces.

It is also necessary that the builder provides an ionic strength favorable to the functioning of the surfactants, in particular by increasing the size of the micelles.

It must also provide OH⁻ ions, for the saponification of fats and again, for the increase of the negative surface charges of textile surfaces and particulate stains.

Silicates have long been considered good detergency builders, particularly in combination with tripolyphosphates as in US-A-2,909,490, but they are currently used less in phosphate-free compositions for washing machines.

Detergent formulations comprising silicate with an SiO₂ / Na₂O ratio of between 0.9 and 1.6, and more preferably of the order of 1, sodium carbonate, tripolyphosphate and copolymers of acrylic and maleic acid have been proposed in patent EP-A-353,562.

The most used silicates in the detergency application are those having a SiO₂ / Na₂O molar ratio of between 1.6 and 2.4.
They are sold either in the form of concentrated solutions containing approximately 35-45% by weight of dry extract, or in the form of powdered silicate, atomized and optionally compacted.

The concentrated commercial solutions are most often prepared from completely amorphous silicate called "glassy", also called "water glass".

These soluble glasses are water-solubilized in an autoclave under pressure at 140 ° C. Commercial solutions are thus obtained having a dry extract of about 45% by weight for a silicate of ratio 2 and about 35% for a silicate of ratio 3.5.

The concentrated silicate solutions are introduced by the detergent formulator into the aqueous suspension (slurry) containing the other constituents of the detergent. The slurry is then spray dried. The silicate, coatomised and co-dried with the other constituents, no longer contains more than 20% of associated water relative to its dry weight, or even less.

As for commercial powdered silicate, it is obtained by spray drying of concentrated solutions of glassy silicate; it is necessary to conserve 20 to 22% by weight of water relative to the finished product to ensure good solubility of said product.

It has been found that, when dissolved in a washing bath in the proportion of 1 to 3 g / liter, this powdered silicate which contains only 20 to 22% by weight of associated water (relative to the finished product), has only weak builder properties.

Indeed, this powdered silicate in solution essentially generates monomeric silicic species of formula Si (OX) ₄ where X represents H or Na, having no builder effect. Such monomeric species can only re-associate with each other to form polyanions if the silicate concentration is at least 50 to 500 g / liter and this slowly.

Such silicate concentrations as well as the slow polymerization kinetics of the monomeric species are not compatible with the conditions and the durations of washing in a washing machine.

What has been observed for a powder containing 20 to 22% of chemically associated water (relative to the finished product) is of course valid for formulations containing a silicate with 20% associated water (relative to dry silicate) prepared by introducing a concentrated silicate solution into a slurry, then drying.

Patent DE-A-2 322 123 describes the preparation of silicate carbonate particles consisting in bringing a silicate solution into contact with carbonate particles, then in drying the mixture so as to remove the water vapor from the silicate.

Patent FR-A-2 143 093 describes the co-drying by atomization of a silicate solution mixed with an additive such as in particular sodium carbonate. This co-drying is carried out at a temperature between 300 and 450 ° C. so that the water contained in the silicate vaporizes and escapes.

US-A-4,761,248 also describes a process for the preparation of hydrated particles from a hydratable anhydrous compound and a silicate solution, the water of the latter ensuring the hydration of the hydratable compound.

US-A-4,427,417 describes the mixture of agglomerates of hydratable detergent particles and a silicate solution, the water of the latter serving to hydrate the hydratable compounds, followed by drying.

The Applicant has found that when an alkali metal silicate is rich in species in which the silicon atoms are in Q₂ and Q₃ form, the polyanionic species formed by dilution up to 1 to 3 g / l in a washing medium have a duration of sufficient life to allow them to play a role of "builder" in detergency.

The expression "silicon atoms in Q₂ and Q₃ form" is a representation of the degree of association of the silicon atoms with each other; "Q₂" means that each silicon atom participates in two -Si-O-Si- bonds, the two remaining bonds being a -Si-OX termination where X is an alkali metal or H; "Q₃" means that each silicon atom participates in three -Si-O-Si- bonds, the remaining bond being a -Si-OX termination.

A first object of the invention consists in the use as a builder agent in a detergent composition of an aqueous solution of alkali metal silicate, in particular of sodium or potassium, at approximately 10 to 60% by weight. dry extract, preferably about 35 to 50%, and SiO2 / M2O molar ratio of the order of 1.6 to 3.5, preferably of the order of 1.8 to 2.6, containing at least at least 30% of silicon atoms in Q2 and Q3 form, preferably at least 50%.

The concentrated solution of alkali metal silicate used as “builder” agent is preferably obtained by water-solubilization of “soluble glasses” in an autoclave under pressure at 140 ° C., then optional dilution; it can also be obtained by other known means, such as direct attack on sand with caustic soda in concentrated solution.

• . une solution à 45 % d'extrait sec de silicate vitreux de rapport molaire SiO₂/Na₂O = 2 contient 34 % d'espèces Q₃, 51 % d'espèces Q₂, 12 % d'espèces Q₁ et 3 % d'espèces Q₀.
• . une solution à 35 % d'extrait sec de rapport 3,5 contient 46 % d'espèces Q₃, 27 % d'espèces Q₂, 16 % d'espèces Q₄, 9 % d'espèces Q₁ et 2 % d'espèces Q₀.

NMR analysis shows that:

• . a 45% solution of dry extract of vitreous silicate with a SiO₂ / Na₂O molar ratio = 2 contains 34% of Q₃ species, 51% of Q₂ species, 12% of Q₁ species and 3% of Q₀ species.
• . a 35% solution of 3.5 ratio dry extract contains 46% Q₃ species, 27% Q₂ species, 16% Q₄ species, 9% Q₁ species and 2% Q₀ species.

Said "builder" solution can be used in post addition by spraying on the "bottom of tower" washing powder in the case of an atomization installation or on the mixture of the components of the washing formula in the case of a mixing with dry, and within the limit of the adsorption capacity of the powders. The pulverulent mixture obtained can be dried moderately if necessary, so that the dry silicate / water weight ratio remaining associated with the silicate is between 100/120 and 100/40, preferably between 100/90 and 100/50.

The quantity of silicate solution that can be used is such that the dry silicate / detergent powder weight ratio is between 1/100 and 30/100, preferably of the order of 10/100 to 20/100.

Another non-limiting embodiment of the invention consists of an aqueous solution of about 10-60%, preferably about 35-50% by weight of dry extract of an alkali metal silicate, especially sodium or potassium. , of SiO₂ / M₂O molar ratio of the order of 1.6 to 3.5, preferably of the order of 1.8 to 2.6, adsorbed and / or absorbed on a particulate support inert with respect to silicate, the silicate weight ratio expressed as dry / water remaining associated with the silicate ranging from 100/120 to 100/40, preferably ranging from 100/90 to 100/50. "Inert" means chemically inert.

The term “water” associated with the silicate is understood to mean the water of the supported solution which is not combined with the mineral support, in particular in the form of crystallized hydrate.

A second object of the invention consists of a "builder" agent, characterized in that it is capable of being obtained by adsorption and / or absorption by bringing into contact a concentrated aqueous solution of an alkali metal silicate of SiO2 / M2O ratio of the order of 1.6 to 3.5, preferably of the order of 1.8 to 2.6, and having a solids content of the order of 10 to 60%, preferably of on the order of 35 to 50%, containing at least 30% of silicon atoms, preferably at least 50%, with an inert inorganic support with respect to the silicate, said support being different from sodium tripolyphosphate and being present in an amount such that the amount of water remaining associated with said silicate after adsorption and / or absorption corresponds to a silicate weight ratio expressed in dry / water associated with the silicate of the order of 100/120 to 100/40, preferably from 100/90 to 100/50.

Among the organic supports of the silicate solution, mention may be made of preferably water-soluble compounds such as: sodium carbonate, sodium sulfate, sodium borate, sodium perborate, sodium metasilicate, phosphates such as trisodium phosphate, ..., these supports being present alone or as a mixture between them.

The support generally represents of the order of 55 to 95%, preferably of the order of 65 to 85% of the weight of the supported solution expressed in dry (i.e. weight of solution expressed in dry + weight support).

The contacting operation can be carried out by adding, in particular by spraying, said concentrated silicate solution to the support in particulate form, in any known mixer with high shear, in particular of the LODIGE® type, or in the granulation tools ( drum, plate ...) ..., at a temperature of around 20 to 95 ° C, preferably around 70 to 95 ° C.

The supports that can be used are those already mentioned in the above list.

The quantity and the concentration of the silicate solution to be used depend on the absorbing and / or adsorbing power of the support, taking into account a possible possibility for said support to form in particular crystallizable hydrates; the level of water not associated with the silicate which may be in the form of a hydrate in the support can be determined in a known manner by differential thermal analysis or by quantitative X-ray diffraction. The water possibly combined with the support in forms other than defined hydrates can be determined by appropriate physicochemical methods (thermoporosimetry, thermogravimetry, proton NMR, IR).

The limit of absorbent and / or adsorbent capacity of said support can be determined according to known methods, for example by measuring the evolution of the angle at the base of the slope of slope as a function of the rate of addition of the solution of silicate.

If necessary, the mixture consisting of the support and the silicate solution can itself be dried, but in a moderate manner so as to obtain the desired proportions of water associated with the silicate.

The particles of supported silicate solution obtained can be ground, if desired, so as to obtain an average diameter of the order of 200 to 800 micrometers.

Solutions of alkali metal silicate in the form adsorbed and / or absorbed on an alkali metal carbonate and being in the form of spherical cogranules of hydrated alkali metal silicate and alkali metal carbonate are builder agents of the invention particularly efficient.

• on pulvérise une solution aqueuse à base de silicates de métaux alcalins contenant au moins 30% d'atomes de silicium sous forme Q2 et Q3 ou à base d'un mélange desdits silicates et de carbonates de métaux métaux alcalins sur un lit roulant de particules à base de carbonates de métaux alcalins défilant dans un dispositif rotatif de granulation, la vitesse de défilement des particules, l'épaisseur du lit roulant et le débit de la solution pulvérisée étant tels que chaque particule se transforme en un cogranulé plastique en entrant en contact avec d'autres particules,
• on soumet les cogranulés obtenus à une opération de densification,
• on sèche lesdits cogranulés densifiés, jusqu'à obtenir une teneur en eau associée au silicate correspondant à un rapport pondéral silicate exprimé en sec/eau associée au silicate de l'ordre de 100/120 à 100/40.

Another subject of the invention consists of spherical cogranules of hydrated alkali metal silicates and alkali metal carbonates, characterized in that they are capable of being prepared according to a process comprising the following steps:

• an aqueous solution based on alkali metal silicates containing at least 30% of silicon atoms in the form Q2 and Q3 is sprayed or based on a mixture of said silicates and carbonates of alkali metal metals on a rolling bed of particles base of alkali metal carbonates traveling in a rotary granulation device, the speed of movement of the particles, the thickness of the moving bed and the flow rate of the sprayed solution being such that each particle is transformed into a plastic cogranulate by coming into contact with other particles,
• the cogranules obtained are subjected to a densification operation,
• said densified cogranules are dried, until a water content associated with the silicate corresponding to a silicate weight ratio expressed as dry / water associated with the silicate of the order of 100/120 to 100/40 is obtained.

Among the alkali metal silicates and carbonates, mention may preferably be made of those of sodium and potassium, and very particularly those of sodium.

The aqueous solution based on silicate or on a sprayed silicate / carbonate mixture may have a dry extract content of the order of 30 to 55% by weight, preferably 30 to 45% by weight; said alkali metal silicate has a SiO2 / M2O molar ratio of the order of 1.6 to 3.5, preferably of the order of 1.8 to 2.6 and all particularly close to 2; said carbonate may optionally be present in proportions depending on the desired final product.

The spraying of the silicate-based solution or of a silicate / carbonate mixture is carried out at a temperature of the order of 20 to 95 ° C, preferably of the order of 70 to 95 ° C; this can be promoted by the joint introduction (for example using a two-fluid nozzle) of pressurized air at a temperature of the same order.

• . un diamètre moyen de l'ordre de 10 à 150 10⁻⁶ m de préférence de l'ordre de 20 à 100 10⁻⁶ m tout particulièrement voisin de 30 à 80, 10⁻⁶ m
• . une densité de remplissage non tassée (non bulk density) de l'ordre de 0,4 à 1,1 g/cm3, de préférence de l'ordre de 0,6 à 1,1 g/cm3,
• . une teneur en eau de l'ordre de 0,05 à 0,4%, de préférence de l'ordre de 0,1 à 0,3% en poids,
• . un taux de matières insolubles de l'ordre de 5 à 100 mg/kg, généralement de l'ordre de 10 à 60 mg/kg.

The particles used to prepare the cogranules mainly consist of alkali metal carbonate having:

• . an average diameter of the order of 10 to 150 10⁻⁶ m preferably of the order of 20 to 100 10⁻⁶ m very particularly close to 30 to 80, 10⁻⁶ m
• . a non-bulk density of the order of 0.4 to 1.1 g / cm3, preferably of the order of 0.6 to 1.1 g / cm3,
• . a water content of the order of 0.05 to 0.4%, preferably of the order of 0.1 to 0.3% by weight,
• . an insoluble matter level of the order of 5 to 100 mg / kg, generally of the order of 10 to 60 mg / kg.

Common grades, milled or not, of carbonate can be used.

Besides these carbonate particles may be present small amounts (less than 10% of the weight of the cogranules) of other particles, such as anti-deposition polymers (carboxymethyl - cellulose ...), enzymes ... commonly used in the detergency domain, having a diameter and a density close to those of carbonate particles.

The device used to carry out the co-granulation operation by spraying can be any rotary device of the rotating plate, bezel, rotating drum, mixer-granulator type, etc.

A first preferred embodiment of these cogranules consists in using a rotary granulator allowing the particles to travel in a thin layer. The beziers having an axis of rotation inclined relative to the horizontal at an angle greater than 20 °, preferably greater than 40 °, are particularly well suited; their geometry can be very diverse: frusto-conical, flat, stepped, a combination of these three forms ...

A second preferred embodiment of these cogranules consists in using a rotary drum, the angle of inclination of which is at least 3% and preferably at least 5%.

The carbonate-based particles pass at a temperature of on the order of 15 to 200 ° C, preferably on the order of 15 to 120 ° C and most particularly on the order of 15 to 30 ° C.

The quantities of silicate-based solution or of silicate / carbonate mixture to be sprayed and of carbonate-based particles to be used correspond to a liquid flow rate / particle flow rate which can range from 0.2 to 0.8 l / kg, preferably from 0.4 to 0.7 l / kg and very particularly from 0.62 to 0.7 l / kg, these values being expressed as sodium salts.

The flow rate of the sprayed solution, the speed of movement of particles as well as the thickness of the layer of particles in movement are such that each particle absorbs liquid and agglomerates with the other particles with which it comes into contact in order to obtain plastic granules and not a paste.

The speed of movement of the particles and the thickness of the layer are regulated by the rate of introduction of the particles into the granulation device and by the characteristics of the latter.

The residence time of the particles in a device of the plate or drum type is generally of the order of 15 to 40 minutes.

• . sa géométrie (troncônique, plat, en escalier, ou combinaison des trois formes),
• . ses dimensions (profondeur, diamètre),
• . son angle d'inclinaison,
• . sa vitesse de rotation,
• . les positions relatives des alimentations en solide et en liquide.

It is within the reach of the skilled person, depending on a given raw material, to adapt the characteristics of the device used to the desired product; to know for a bezel:

• . its geometry (frusto-conical, flat, stepped, or combination of the three forms),
• . its dimensions (depth, diameter),
• . its angle of inclination,
• . its speed of rotation,
• . the relative positions of the solid and liquid supplies.

• . sa géométrie (diamètre du tube)
• . son angle d'inclinaison
• . sa vitesse de rotation
• . la charge du tube
• . les positions relatives des alimentations en solide et en liquide.

For a drum:

• . its geometry (tube diameter)
• . its angle of inclination
• . its rotation speed
• . tube load
• . the relative positions of the solid and liquid supplies.

• . une teneur en silicate de l'ordre de 7 à 30 % en poids, de préférence de l'ordre de 11 à 23 % en poids, et tout particulièrement de l'ordre de 21 à 23 % en poids,
• . une teneur en carbonate de l'ordre de 41 à 75 % en poids, de préférence de l'ordre de 48 à 64 % en poids et tout particulèrement de l'ordre de 48 à 51 % en poids,
• . une teneur en eau de l'ordre de 18 à 29 %, de préférence de l'ordre de 25 à 29 %, en poids, et tout particulièrement de l'ordre de 27 à 29 % en poids.

The non-densified and non-dried cogranules obtained have characteristics which depend on the conditions used to produce granulation. They generally present:

• . a silicate content of the order of 7 to 30% by weight, preferably of the order of 11 to 23% by weight, and very particularly of the order of 21 to 23% by weight,
• . a carbonate content of the order of 41 to 75% by weight, preferably of the order of 48 to 64% by weight and very particularly of the order of 48 to 51% by weight,
• . a water content of the order of 18 to 29%, preferably of the order of 25 to 29%, by weight, and very particularly of the order of 27 to 29% by weight.

The densification operation can be carried out at ambient temperature by rolling the cogranules obtained in the granulation step in a rotary device.

This device is preferably independent of that of granulation.

This densification step can advantageously be carried out by introduction and stay of the cogranules in a rotary drum. The angle of inclination of the latter is at least 3%, preferably at least 5%. The dimensions of this drum, its speed of rotation and the residence time of the cogranules depend on the density sought; the residence time is generally of the order of 20 minutes to 3 hours, preferably of the order of 20 to 90 minutes.

Mixer-granulators are also well suited to this densification operation.

The cogranulation and densification operations can also be carried out in the same device, for example in a stepped bezel, the densification of the cogranules being obtained by rolling said cogranules on the last steps of the apparatus; similarly, these two operations can be carried out in a drum with two sections.

The densified cogranules are then dried by any known means. A particularly effective method is drying in a fluidized bed using an air stream at a temperature of the order of 40 to 90 ° C, preferably from 60 to 80 ° C. This operation is carried out for a period depending on the air temperature, the water content of the cogranules at the outlet of the granulation device and that desired of the dried cogranules, as well as the fluidization conditions; the skilled person knows how to adapt these different conditions to the product sought.

• une teneur en silicate de l'ordre de 8 à 38 % en poids, de préférence de l'ordre de 14 à 31 % en poids, et tout particulièrement de l'ordre de 24 à 31 % en poids,
• une teneur en carbonate de l'ordre de 47 à 87 % en poids, de préférence de l'ordre de 59 à 81 % en poids, tout particulièrement de l'ordre de 64 à 69 % en poids,
• une teneur en eau de l'ordre de 5 à 25 % en poids, de préférence de l'ordre de 7 à 20 % en poids, et tout particulièrement de 12 à 20 % en poids,
• une densité de remplissage non tassée de l'ordre de 0,7 à 1,5 g/cm3 de préférence de l'ordre de 0,75 à 1,5 g/cm3 et tout particulièrement de l'ordre de 0,8 à 1 g/cm3,
• un diamètre médian (au sens des pourcentages cumulés passants) de l'ordre de 0,4 à 1,8 mm, de préférence de l'ordre de 0,6 à 0,8 mm, avec un écart type log₁₀ de 0,02 à 0,3, de préférence de 0,05 à 0,1.

Dried dense cogranules generally have:

• a silicate content of the order of 8 to 38% by weight, preferably of the order of 14 to 31% by weight, and very particularly of the order of 24 to 31% by weight,
• a carbonate content of the order of 47 to 87% by weight, preferably of the order of 59 to 81% by weight, very particularly of the order of 64 to 69% by weight,
• a water content of the order of 5 to 25% by weight, preferably of the order of 7 to 20% by weight, and very particularly of 12 to 20% by weight,
• an unfilled filling density of the order of 0.7 to 1.5 g / cm3, preferably of the order of 0.75 to 1.5 g / cm3 and very particularly of the order of 0.8 to 1 g / cm3,
• a median diameter (in the sense of the cumulative passing percentages) of the order of 0.4 to 1.8 mm, preferably of the order of 0.6 to 0.8 mm, with a log standard deviation of 0.02 to 0.3, preferably from 0.05 to 0.1.

These cogranulation / densification / drying stages make it possible to obtain cogranules based on hydrated alkali metal silicates and perfectly spherical, dense and rapidly dissolving alkali metal carbonates.

• une teneur en silicate de l'ordre de 24 à 31 % en poids,
• une teneur en carbonate de l'ordre de 64 à 69 % en poids,
• une teneur en eau de 12 à 20 % en poids,
• une densité de remplissage non tassé de l'ordre de 0,7 à 1,5 g/cm3, de préférence de l'ordre de 0,8 à 1,
• un diamètre médian de l'ordre de 0,4 à 0,8 mm, avec écart type log₁₀ de 0,05 à 0,1.
• une vitesse de dissolution à 90 % dans l'eau inférieure à 2 minutes et à 95 % inférieure à 4 minutes.

Spherical cogranules based on hydrated sodium silicates and sodium carbonate particularly suitable for the preparation of detergent compositions for dishwashing machines and washing machines are those having the following characteristics:

• a silicate content of the order of 24 to 31% by weight,
• a carbonate content of the order of 64 to 69% by weight,
• a water content of 12 to 20% by weight,
• an unfilled filling density of the order of 0.7 to 1.5 g / cm3, preferably of the order of 0.8 to 1,
• a median diameter of the order of 0.4 to 0.8 mm, with standard deviation log₁₀ from 0.05 to 0.1.
• a dissolution rate of 90% in water less than 2 minutes and 95% less than 4 minutes.

The term dissolution rate at 90% or 95% in water means the time necessary to dissolve 90% or 95% of the product at a concentration of 35 g / l in water at 20 ° C.

When it is structured (powder, co-granulated, etc.) the builder agent of the invention is used in detergent compositions for dishwashers at a rate of 3 to 90% by weight, preferably from 3 to 70% by weight of said compositions; the quantities used in the compositions for washing machines are of the order of 3 to 60%, preferably of the order of 3 to 40% of the weight of said compositions (these quantities are expressed by weight of dry silicate relative to by weight of composition).

In addition to the builder agent which is the subject of the invention, at least one surfactant is present in the detergent composition in an amount which can range from 8 to 20%, preferably of the order of 10 to 15. % of the weight of said composition.

• les agents tensio-actifs anioniques du type savons de métaux alcalins (sels alcalins d'acides gras en C₈ - C₂₄), sulfonates alcalins (alcoylbenzène sulfonates en C₈ - C₁₃, alcoylsulfonates en C₁₂ - C₁₆), alcools gras en C₆ - C₁₆ oxyéthylénés et sulfatés, alkylphénols en C₈ -C₁₃ oxyéthylénés et sulfatés, les sulfosuccinates alcalins (alcoylsulfosuccinates en C₁₂ - C₁₆)...
• les agents tensio-actifs non ioniques du type alcoylphénols en C₆ - C₁₂ polyoxyéthylénés, alcools aliphatiques en C₈ - C₂₂ oxyéthylénés, les copolymères bloc oxyde d'éthylène - oxyde de propylène, les amides carboxyliques éventuellement polyoxyéthylénés,
• les agents tensio-actifs amphotères du type alcoyldiméthylbétaïnes,
• les agents tensio-actifs cationiques du type chlorures ou bromures d'alkyltriméthylammonium, d'alkyldiméthyléthylammonium.
  Divers constituants peuvent en outre être présents dans la composition lessivielle tels que :
• des "builders" du type :
  • . phosphates à raison de moins de 25 % du poids total de formulation,
  • . zéolithes jusqu'à environ 40 % du poids total de formulation,
  • . carbonate de sodium jusqu'à environ 80 % du poids total de formulation,
  • . acide nitriloacétique jusqu'à environ 10 % du poids total de formulation,
  • . acide citrique, acide tartrique jusqu'à environ 20 % du poids total de formulation, la quantité totale de "builder" correspondant à environ 0,2 à 80 %, de préférence de 20 à 45 % du poids total de ladite composition détergente,
• des agents de blanchiment du type perborates, percarbonates, chloroisocyanurates, N, N, N', N'-tétraacétyléthylènediamine (TAED) jusqu'à environ 30 % du poids total de ladite composition détergente,
• des agents anti-redéposition du type carboxyméthylcellulose, méthylcellulose en quantités pouvant aller jusqu'à environ 5 % du poids total de ladite composition détergente,
• des agents anti-incrustation du type copolymères d'acide acrylique et d'anhydride maléique en quantité pouvant aller jusqu'à 10 % environ du poids total de ladite composition détergente,
• des charges du type sulfate de sodium pour les détergents en poudre en quantité pouvant aller jusqu'à 50 % du poids total de ladite composition détergente.

Among these surfactants, mention may be made of:

• anionic surfactants such as alkali metal soaps (alkali salts of C₈ - C₂₄ fatty acids), alkali sulfonates (C₈ - C₁₃ alkylbenzene sulfonates, C₁₂ - C₁₆ alkylsulfonates) and C₆ - C₁₆ fatty alcohols and sulfates, oxyethylenated and sulfated C₈ -C₁₃ alkylphenols, alkali sulfosuccinates (C₁₂ - C₁₆ alkyl sulfosuccinates) ...
• non-ionic surfactants of the polyoxyethylene C₆ - C₁₂ alkylphenol type, oxyethylenated C₈ - C₂₂ aliphatic alcohols, ethylene oxide-propylene oxide block copolymers, optionally polyoxyethylenated carboxylic amides,
• amphoteric surfactants of the alkyl dimethyl betaines type,
• cationic surfactants of the chlorides or bromides type of alkyltrimethylammonium, of alkyl dimethylethyl ammonium.
  Various constituents can also be present in the detergent composition such as:
• "builders" like:
  • . phosphates at a rate of less than 25% of the total weight of the formulation,
  • . zeolites up to around 40% of the total formulation weight,
  • . sodium carbonate up to approximately 80% of the total formulation weight,
  • . nitriloacetic acid up to approximately 10% of the total formulation weight,
  • . citric acid, tartaric acid up to approximately 20% of the total weight of formulation, the total amount of "builder" corresponding to approximately 0.2 to 80%, preferably from 20 to 45% of the total weight of said detergent composition,
• bleaching agents of the perborates, percarbonates, chloroisocyanurates, N, N, N ', N'-tetraacetylethylenediamine (TAED) type up to approximately 30% of the total weight of said detergent composition,
• anti-redeposition agents of the carboxymethylcellulose, methylcellulose type in amounts which can range up to approximately 5% of the total weight of said detergent composition,
• anti-scaling agents of the acrylic acid and maleic anhydride copolymer type in an amount which can range up to approximately 10% of the total weight of said detergent composition,
• fillers of the sodium sulfate type for powdered detergents in an amount which can range up to 50% of the total weight of said detergent composition.

The following examples are given for information only and cannot be considered as limiting the invention.

EXAMPLES 1 to 5

• d'une solution de silicate de sodium de rapport molaire SiO₂/Na₂O = 2 à 45 % en poids d'extrait sec (exemple 2)
• d'une solution de silicate de sodium de rapport molaire SiO₂/Na₂O = 3,4 à 35 % en poids d'extrait sec (exemple 4) sont mesurées dans un TERGOTOMETRE (US Testing Company, Hoboken, USA), en mélange binaire avec un surfactant anionique LABS (dodecyl benzène sulfonate de sodium linéaire de ALDRICH), les mesures de réflectance étant réalisées à l'aide d'un reflectomètre GARDNER®.

"Builder" performances

• of a sodium silicate solution with a SiO₂ / Na₂O molar ratio = 2 to 45% by weight of dry extract (example 2)
• of a sodium silicate solution with a SiO₂ / Na₂O molar ratio = 3.4 to 35% by weight of dry extract (Example 4) are measured in a TERGOTOMETER (US Testing Company, Hoboken, USA), in binary mixture with an LABS anionic surfactant (linear sodium dodecyl benzene sulfonate from ALDRICH), the reflectance measurements being carried out using a GARDNER® reflectometer.

• du LABS seul à 2 g/l (exemple 1)
• d'une poudre atomisée de silicate de rapport 2 contenant 22 % d'eau (soit 28,2 % d'eau par rapport au silicate sec) (exemple 3)
• d'une poudre atomisée de silicate de rapport 3,4 contenant 18,6 % d'eau (soit 22,8 % d'eau par rapport au silicate sec) (exemple 5) mises en oeuvre dans les mêmes conditions (4 g/l).

These performances are compared to those:

• LABS alone at 2 g / l (example 1)
• an atomized silicate powder of ratio 2 containing 22% of water (i.e. 28.2% of water relative to the dry silicate) (example 3)
• of an atomized powder of silicate of ratio 3.4 containing 18.6 % of water (ie 22.8% of water relative to the dry silicate) (example 5) used under the same conditions (4 g / l).

The results of these measurements are shown in Table I Measurement method Principle:

A simplified machine washing is simulated in a tergotometer, by washing standardized soiled tissue test tubes at 65 ° C. with a surfactant and the builder to be tested. Washing takes twenty minutes and the color of the fabrics is measured before and after washing. We make a "blank", by washing the same type of test tubes with the surfactant alone, to evaluate the performance of the builder tested.

Operating mode :

The tergotometer is a device made up of 4 2-liter stainless steel pots on which are fitted pulsators which are set at 100 cycles per minute. The pots are placed in a water tank regulated at 65 ° C.

1) In each pot we put 1l of hard tap water (34 ° TH French) When the water is at temperature, we introduce:

• 5 x 10 X 12 cm white cotton 405 W style test tubes from TEST FABRIC.
• 5 test pieces of 10 X 12 cm white polyestercotton (PEC) reference n ° 7435 from the company TEST FABRIC.
• 2 test tubes of 10 X 12 cm of soiled cotton EMPA® (mixture of Chinese ink and olive oil) article 101 of the company GALLEN.
• 2 test tubes of 10 X 12 cm of cotton soiled red wine article 114 of the company GALLEN.
• 2 x 10 X 12 cm polyestercotton (PEC) soiled EMPA® article 104 specimens from the company GALLEN.

2) The following 3 operations are carried out simultaneously:

• . stopwatch start
• . start of agitation
• . addition of builder / surfactant mixture

The builder is tested at 4 g / l (mass counted as dry matter of product) and 2 g / l of LABS are added thereto.

3) Rinsing

When twenty minutes have passed, the washing water is thrown away and the fabrics are rinsed with 3 X 1 l of cold tap water.

4) Spinning and drying

The specimens are wrung out and pre-dried by spreading them individually in absorbent paper. The fabrics are then passed twice in a freezer between two sheets of absorbent paper at a temperature of approximately 110 ° C.

5) Color measurement

• L situe la couleur dans les teintes du blanc au noir.
  • L = 100 correspond à éprouvette blanche
  • L = 0 correspond à éprouvette noire
• a situe la couleur dans les teintes du vert au rouge.
  • a > o : la couleur tire sur le rouge
  • a < o : la couleur tire sur le vert
• b situe la couleur dans les teintes du jaune au bleu.
  • b > o : la couleur tire sur le jaune
  • b < o : la couleur tire sur le bleu

The GARDNER® device is calibrated by measuring zero on a black plate reserved for this purpose and then by reading values L, a, b on a standardized white plate of the same type as the black one.

• L places the color in shades from white to black.
  • L = 100 corresponds to white test tube
  • L = 0 corresponds to black test tube
• located the color in shades from green to red.
  • a> o: the color turns to red
  • a <o: the color turns to green
• b locates the color in shades from yellow to blue.
  • b> o: the color turns to yellow
  • b <o: the color turns to blue

After calibration, the actual measurements are made. By pot we take 2 test tubes from each category of fabrics, we make 5 measurements per test tube (that is to say one in the center and one at the four corners) by placing on the fabric a heavy metal plate, then we make the arithmetic mean of the 10 determinations. We proceed in the same way with unwashed fabrics.

6) Exploitation of results

• DL = L après lavage - L avant lavage
• Da = a avant lavage - a après lavage
• Db = b avant lavage - b après lavage $$\text{DE =}\sqrt{{\text{DL}}^{\text{2}}{\text{+ Da}}^{\text{2}}{\text{+ Db}}^{\text{2}}}\text{= Détergence}$$
  

DL and DE are calculated for each test and for each type of tissue.

• DL = L after washing - L before washing
• Da = a before washing - a after washing
• Db = b before washing - b after washing $$\text{DE =}\sqrt{{\text{DL}}^{\text{2}}{\text{+ Da}}^{\text{2}}{\text{+ Db}}^{\text{2}}}\text{= Detergency}$$
  

The average DL and DE is calculated for each product and each type of soiled tissue.

• Dét(ergence) coton EMPA® = DE moyen coton EMPA®
• Dét(ergence) PEC EMPA® = DE moyen PEC EMPA®
• Dét(ergence) coton VIN = DE moyen coton VIN
• Dét(ergence) cumulée = Somme des détergences coton EMPA®, PEC EMPA®, coton VIN

Then for each product, we calculate:

• Det (ergonomics) EMPA® cotton = DE EMPA® medium cotton
• Det (ergonomics) PEC EMPA® = DE average PEC EMPA®
• Det (ergonomics) cotton VIN = DE medium cotton VIN
• Cumulative det (ergence) = Sum of detergents EMPA® cotton, PEC EMPA®, cotton WINE

EXAMPLES 6 and 7

Examples 6 and 7 are not included in the invention.

A LODIGE M5G® mixer (sold by LODIGE) is loaded with 800 g of anhydrous H₂® tripolyphosphate sold by Rhône-Poulenc.

After closing and rotating the device at a speed of 400 rpm. 200 g of a sodium silicate solution with a SiO₂ / Na₂O molar ratio = 2 to 45% of dry extract are introduced by spraying.

This addition lasts 10 min .; after 10 min. additional mixing by rotation, the product is removed and left to stand for 2 hours on a tray in the open air and at room temperature.

• TPP partiellement hydraté : 82 % en poids
• silicate de sodium : 9 % en poids
• eau associée au silicate : 9 % en poids, soit 100 % par rapport au silicate sec.
  On détermine la quantité d'eau totale contenue dans le produit par la mesure de la perte du poids de ce dernier par chauffage à 500°C ; on mesure d'autre part la quantité d'eau liée sous forme d'hydrates par analyse thermique différentielle. La quantité d'eau associée est calculée par différence entre l'eau totale et l'eau liée sous forme d'hydrate.
• diamètre moyen = 250 micromètres

The product features are as follows:

• TPP partially hydrated: 82% by weight
• sodium silicate: 9% by weight
• water associated with silicate: 9% by weight, ie 100% relative to dry silicate.
  The amount of total water contained in the product is determined by measuring the loss in weight of the latter by heating to 500 ° C .; on the other hand, the quantity of bound water in the form of hydrates is measured by differential thermal analysis. The amount of associated water is calculated by the difference between total water and bound water in the form of hydrate.
• average diameter = 250 micrometers

The "builder" performances of this product are measured according to the method described above, however replacing the 2 PEC dirty EMPA® article 104 test pieces with 2 WFK dirty cotton test pieces from KREFELD, of the same dimensions (example 6).

These performances are compared with those of a mixture of H₂® anhydrous TPP powders and atomized silicate of SiO₂ / Na2O ratio = 2 to 22% water, according to a TPP / dry silicate weight ratio of 800/90, and this under the same conditions (4 g / l) (example 7).

The results of the measurements are shown in Table II.

EXAMPLE 8

• Titre en alcalinité : 99,61 %
• teneur en eau (en poids) = 0,12 %
• densité de remplissage non tassée = 0,56g/cm3
• diamètre médian = 95 10⁻⁶ m
• taux d'insolubles = 58 mg/kg

The granulation system consists of a flat plate with a diameter of 800 mm and a depth of 100 mm. During granulation, the speed of rotation is around 35 rpm. and the inclination of the axis of rotation relative to the horizontal is of the order of 55 °. The pellet plate is continuously fed at a rate of 21.4 kg / h by a powder made up of fine particles of sodium carbonate, the main characteristics of which are as follows:

• Alkalinity titer: 99.61%
• water content (by weight) = 0.12%
• unfilled filling density = 0.56g / cm3
• median diameter = 95 10⁻⁶ m
• insoluble level = 58 mg / kg

On this powder brought into rotation in the granulating dish is sprayed with air at 80 ° C a solution of sodium silicate at a rate of 13.4 l / h at a temperature of 80 ° C per l 'via a bi-fluid nozzle located at a distance of 20 cm from the bottom of the bezel. The active material content and the SiO₂ / Na₂O molar ratio of the sprayed solution are 43% (by weight) and 2, respectively.

The average residence time of a particle in the plate is approximately 10 to 15 min. The temperature of the particles leaving the plate is ambient temperature.

The plate outlet granules are introduced into a smooth-walled rotating tube with a diameter of 500 mm, a length of 1300 mm and having an inclination of the order of 5%. The outlet diaphragm is adjusted so that the average residence time of a particle is approximately 40 min. The speed of rotation of the drum (18 rpm) is chosen so as to have a rolling bed of particles, which promotes densification of the latter.

• teneur en carbonate (en poids) = 65 %
• teneur en silicate (en poids) = 21 % ± 0,5 %
• teneur en eau (en poids) = 13,5 %
• densité de remplissage non tassée = 0,90 g/cm3
• % en poids de refus à 1 mm = 10,8 %
• diamètre médian = 0,73 mm
• % en poids de passant à 0,2 mm = 6 %
• 90 % (en poids) du produit se dissout en 50 s (solution aqueuse à 35 g/l à 20°C),
• 95 % (en poids) du produit se dissout en 65 s (solution aqueuse à 35 g/l à 20°C),
• blancheur L = 96,3
• résistance à l'attrition : 7 %,

The granules thus obtained are dried in a fluidized bed at a temperature of the order of 80 ° C (temperature of the fluidizing air equal to 85 ° -90 ° C) for 10 to 15 min.
The product thus dried has the following characteristics:

• carbonate content (by weight) = 65%
• silicate content (by weight) = 21% ± 0.5%
• water content (by weight) = 13.5%
• unfilled filling density = 0.90 g / cm3
• % by weight of refusal at 1 mm = 10.8%
• median diameter = 0.73 mm
• % by weight from 0.2 mm = 6%
• 90% (by weight) of the product dissolves in 50 s (aqueous solution at 35 g / l at 20 ° C),
• 95% (by weight) of the product dissolves in 65 s (35 g / l aqueous solution at 20 ° C),
• whiteness L = 96.3
• attrition resistance: 7%,

The granules exhibit excellent storage behavior.

Measurement of attrition resistance : Material:

We use the flourometer, a standardized device used to qualify hydraulic binders and described in French standard P 15-443.

Procedure:

Sieve 50g of product between the 1200 and 180 10⁻⁶ m sieve, using a ROTO-LAB ® laboratory sieve shaker (marketed by PROLABO).

Recover the part between 180 and 1200 10⁻⁶ m.

Weigh approximately exactly 25 g of the product to be tested; let M be the exact mass.

Place them in the flourometer.

Weigh an empty and dry Soxlhet® type filter (marketed by PROLABO) and place it at the top of the fluidization tube; let M1 be its mass.

Fluidize for 5 min. (dry air flow: 15 l / min.).

Recover the product flown in the filter as well as any fines deposited on the vertical walls of the fluidization tube, using a swab of suitable diameter. Weigh ; let M2 be the mass of these fines and the filter.

Sieve again on ROTO LAB ® the residue in the bottom of the fluidization tube and recover, for weighing, fines below 180 10⁻⁶ m; let M3 be the mass of these fines.

Calculation. Expression of the result:

The attrition rate is equal to the percentage of fines <180 microns formed during the fluidization time of the product. $$\text{Attrition\% =}\frac{\text{(M3 + M2-M1)}}{\text{M}}\text{X 100}$$

Example 9:

The operations described in Example 8 are repeated, with the only following modifications:

Granulation :

• . pellet plate: rotation speed of 30 rpm.
• . powder feed: 22kg / h,
• . supply of silicate solution: 13 l / h.

Densification :

• . drum rotation speed: 10 rpm,

Fluid bed drying :

• . temperature = 90 ° C,
• . duration: 20 min.,

• teneur en carbonate (en poids) = 60,9 %,
• teneur en silicate (en poids) = 22,9 % ± 0,5 %,
• teneur en eau (en poids) = 16,1 %
• densité de remplissage non tassée = 0,86 g/cm3
• % en poids de refus à 1 mm = 2,6 %
• diamètre médian = 0,64 mm
• % en poids de passant à 0,2 mm= 7,3 %
• 90 % (en poids) du produit se dissout en 75 s (solution aqueuse à 35 g/l à 20 °C),
• 95 % (en poids) du produit se dissout en 102 s (solution aqueuse à 35 g/l à 20°C),
• blancheur L = 95,6
• résistance à l'attrition : 9,2 %

The dried product has the following characteristics:

• carbonate content (by weight) = 60.9%,
• silicate content (by weight) = 22.9% ± 0.5%,
• water content (by weight) = 16.1%
• unfilled filling density = 0.86 g / cm3
• % by weight of refusal at 1 mm = 2.6%
• median diameter = 0.64 mm
• % by weight from 0.2 mm = 7.3%
• 90% (by weight) of the product dissolves in 75 s (aqueous solution at 35 g / l at 20 ° C),
• 95% (by weight) of the product dissolves in 102 s (35 g / l aqueous solution at 20 ° C),
• whiteness L = 95.6
• attrition resistance: 9.2%

The granules exhibit excellent storage behavior.

Example 10 :

The granulation system consists of a drum rotating at 40 rpm, with smooth walls of diameter 500 mm, length 1300 mm and having an inclination of the order of 7.5%. The output diaphragm is adjusted so that the average residence time of a particle is of the order of 15 to 20 min.

The drum is continuously fed at a flow rate of 37 kg / h by a carbonate powder having the same characteristics as those of the powder of Examples 1 and 2.

On this powder brought into rotation in the drum, is sprayed with air at 80 ° C via a bi-fluid nozzle with flat jet located at the first third of the drum, a silicate solution (having an active material content of 45.6% by weight and a SiO₂ / Na₂O weight ratio of 2) at 80 ° C. with a flow rate of 18 l / h.

The cogranules at the outlet of the drum are at room temperature and have a density of 0.68 g / cm3.

The cogranules are then densified batchwise for one hour in a rotary drum with smooth walls of diameter 500 mm, length 1300 mm and having an inclination of 5%.

The drum rotation speed is 20 rpm.

The granules thus obtained are dried in a fluidized bed at a temperature of the order of 65 ° C (temperature of the fluidizing air equal to 70 ° C) for 15 min.

• teneur en carbonate (en poids) = 62 %,
• teneur en silicate (en poids) = 20,5 % ± 0,5 %,
• teneur en eau (en poids) = 17,6 %
• densité de remplissage non tassée = 0,820
• % en poids de refus à 1 mm = 5 %,
• diamètre médian = 0,65 mm
• % en poids de passant à 0,2 mm = 0,6 %
• 90 % (en poids) du produit se dissout en 50 s (solution aqueuse à 35 g/l à 20°C),
• 95 % (en poids) du produit se dissout en 63 s (solution aqueuse à 35 g/l à 20°C),

The dried product has the following characteristics:

• carbonate content (by weight) = 62%,
• silicate content (by weight) = 20.5% ± 0.5%,
• water content (by weight) = 17.6%
• unfilled filling density = 0.820
• % by weight of refusal at 1 mm = 5%,
• median diameter = 0.65 mm
• % by weight from 0.2 mm = 0.6%
• 90% (by weight) of the product dissolves in 50 s (aqueous solution at 35 g / l at 20 ° C),
• 95% (by weight) of the product dissolves in 63 s (aqueous solution at 35 g / l at 20 ° C),

The granules exhibit excellent storage behavior.

Example 11 :

The operations described in Example 10 are repeated, with the only following modification:

Densification :

• . discontinuously for 2 hours.

• teneur en carbonate (en poids) = 60,8 %,
• teneur en silicate (en poids) = 19,3 % ± 0,5 %,
• teneur en eau (en poids) = 19,9 %
• densité de remplissage non tassée = 0,91 g/cm3
• % en poids de refus à 1 mm = 1,6 %,
• diamètre médian = 0,57 mm
• % en poids de passant à 0,2 mm = 1,22 %
• 90 % (en poids) du produit se dissout en 37 s (solution aqueuse à 35 g/l à 20°C),
• 95 % (en poids) du produit se dissout en 45 s (solution aqueuse à 35 g/l à 20°C),

The dried product has the following characteristics:

• carbonate content (by weight) = 60.8%,
• silicate content (by weight) = 19.3% ± 0.5%,
• water content (by weight) = 19.9%
• unfilled filling density = 0.91 g / cm3
• % by weight of refusal at 1 mm = 1.6%,
• median diameter = 0.57 mm
• % by weight from 0.2 mm = 1.22%
• 90% (by weight) of the product dissolves in 37 s (aqueous solution at 35 g / l at 20 ° C),
• 95% (by weight) of the product dissolves in 45 s (35 g / l aqueous solution at 20 ° C),

The granules exhibit excellent storage behavior.

Examples 12 and 13

The “builder” performances of the cogranules of Example 8 are measured according to the method described in Examples 1 to 5.

They are compared with those of a mixture of sodium carbonate powder and atomized sodium silicate powder of SiO₂ / Na₂O ratio = 2 containing 22% water in the finished product (i.e. 28.2% water by compared to dry silicate) according to a 3/1 weight ratio (carbonate / atomized R₂).

The results are shown in Table III.

The amounts of carbonate and silicate shown in this table are expressed in dry.

It can be seen that the performance of the cogranules is better than that of a mixture of powders having the same silicate / carbonate ratio.

Example 14

• 1800 g de carbonate de soude léger en poudre, présentant un diamètre moyen de l'ordre de 110 µm
• 1200 g de solution de silicate de sodium de rapport molaire SiO₂/Na₂O = 3,4 à 37 % d'extrait sec.

Particles are prepared from a LODIGE M5G ® mixer, according to the procedure of Examples 6 and 7:

• 1800 g of powdered light soda ash, with an average diameter of around 110 µm
• 1200 g of sodium silicate solution with a SiO₂ / Na₂O molar ratio = 3.4 to 37% of dry extract.

• carbonate de sodium : 60 % en poids
• silicate = 20 % en poids
• eau associée au silicate = 20 % en poids (soit 100 % par rapport au silicate sec)
• diamètre moyen = 400 µm

After 5 minutes of addition of the silicate solution, additional 5 minutes of mixing and stay in the open air for 2 hours at room temperature, a product is recovered whose characteristics are as follows:

• sodium carbonate: 60% by weight
• silicate = 20% by weight
• water associated with silicate = 20% by weight (i.e. 100% relative to dry silicate)
• average diameter = 400 µm

This product is introduced by dry mixing with additives in order to obtain the following composition for washing machine: Laundry composition parts by weight . linear alkylbenzene sulfonate 25 . CEMULSOL DB 618 ® 3 . CEMULSOL LA 90 ® (voltage-active SFOS) 2 . zeolite 4A 18 . product of example 14 25.8 . SOKALAN CP5 ® (BASF copolymer) 4 . carboxymethylcellulose 1.5 . TINOPAL DMSX 0.2 . TINOPAL SOP (whiteners from CIBA-GEIGY) 0.2 . ESPERASE ® (NOVO enzyme) 0.3 . RHODORSIL 20444 ® (RHONE-POULENC antifoam) 2 . Na perborate, 4H₂O 15 . TAED 3 pH (10g / l) = 10.25

The dirt removal performance test is carried out in a WASCATOR FOM 71 ® washing machine.

• cycle utilisé : 60°C
• durée totale du cycle : 70 minutes ; pas de prélavage
• nombres de cycles : 3 par lessive
• dureté de l'eau : 32 degrés hydrotimétriques français
• charge de linge : 3,5 kg de torchons en coton blanc
• tissus testés : par lavage, on introduit, en les épinglant sur torchons, deux séries de tissus suivants :

  Coton gris :

  Test-Fabric
  Krefeld 10 C
  IEC 106
  EMPA® 101

  Polyester/coton gris :

  Test-Fabric
  Krefeld 20 C
  EMPA® 104

  Taches protéiniques :

  Sang (EMPA® 111)
  Cacao (EMPA® 112)
  Mixte (EMPA® 116)

  Taches oxydables :

  Thé (Krefeld 10 G)
  Coton écru (EMPA® 222)
  Vin (EMPA® 114)

• Doses de lessives :
     1ère série : 5 g/l soit 5 x 20 = 100 g par lavage
     2ème série : 8 g/l soit 8 x 20 = 160 g par lavage

The test conditions are as follows:

• cycle used: 60 ° C
• total cycle time: 70 minutes; no prewash
• number of cycles: 3 per detergent
• water hardness: 32 French hydrotimetric degrees
• laundry load: 3.5 kg of white cotton tea towels
• fabrics tested: by washing, we introduce, by pinning them on cloths, two series of following fabrics:

  Gray cotton:

  Test-Fabric
  Krefeld 10 C
  IEC 106
  EMPA® 101

  Polyester / gray cotton:

  Test-Fabric
  Krefeld 20 C
  EMPA® 104

  Protein stains:

  Blood (EMPA® 111)
  Cocoa (EMPA® 112)
  Mixed (EMPA® 116)

  Oxidizable spots:

  Tea (Krefeld 10 G)
  Unbleached cotton (EMPA® 222)
  Wine (EMPA® 114)

• Detergent doses:
  1st series: 5 g / l i.e. 5 x 20 = 100 g per wash
  2nd series: 8 g / l i.e. 8 x 20 = 160 g per wash

Method for measuring the removal of dirt and stains

Photometric measurements (measurements of the amount of light reflected by the fabric) make it possible to calculate the percentages of soil removal. We use the ELREPHO 2000 device from DATACALOR.

où

• A = réflectance de l'échantillon blanc témoin
• B = réflectance de l'échantillon sali témoin
• C = réflectance de l'échantillon sali après lavage

The elimination of soiling is expressed by the formula: $$\text{Elimination in\% =}\frac{\text{C - B}}{\text{A - B}}\text{X 100}$$

or

• A = reflectance of the blank control sample
• B = reflectance of the soiled control sample
• C = reflectance of the soiled sample after washing

The reflectances are determined using the blue trichromatic component, without the action of optical brighteners. Number of measurements per sample = 4 Number of samples per wash = 2 Number of washes = 3 Or 4 X 2 X 3 = 24 measurements by soiling, by product and by concentration studied.

The anti-fouling performance test in a washing machine is carried out in a SCHULTESS SUPER 6 DE LUXE ® drum machine

• cycle utilisé : 60°C
• durée totale du cycle = 65 minutes ; pas de prélavage
• nombre de cycles : 25 lavages cumulés
• dureté de l'eau : 21,2 degrés hydrotimétriques français
• tissu test utilisé : bande témoin répondant exactement aux spécifications développées dans la norme NFT 73.600
• charge de linge : 3 kg de serviettes éponges 100 % coton
• doses de lessive : 5 g/l

The test conditions are as follows:

• cycle used: 60 ° C
• total cycle time = 65 minutes; no prewash
• number of cycles: 25 cumulative washes
• water hardness: 21.2 French hydrotimetric degrees
• test tissue used: control strip exactly meeting the specifications developed in standard NFT 73.600
• laundry load: 3 kg of 100% cotton terry towels
• detergent doses: 5 g / l

The test pieces which have been washed 25 times are dried: they are weighed and calcined at 900 ° C.

The% by weight of ash is measured relative to the weight of the starting test pieces.

The results of the various tests are shown in Table IV.

Example 15

A detergent similar to that of Example 14 is prepared by replacing the "builder" mixture

zeolite 4A + product of Example 14 + SOKALAN CP5® by the following "builder" mixture:

The results of the dirt removal and anti-scaling tests are shown in Table IV.

Examples 16-18

The product of Example 8 is introduced by mixing into a LODIGE M5G® with additives in order to obtain compositions for dishwashers.

These compositions are listed in Table V.

These compositions are tested in a MIELE® household dishwasher whose water softener is not regenerated; therefore it delivers hard water with a total hardness of 30 ° TH French.

With each composition used at 3 g / liter of water, 10 cumulative soda-lime glass plates are washed, initially perfectly clean.

The plates are then subjected to a photometric measurement using a GARDNER® device, identical to that used in Examples 1 to 5.

The total amount of light L returned by the sample is measured.

When L is between 4 and 7, the result is considered to be very good, the glass is clear.

When L is between 7 and 14, a slight haze is visible.

The product of Example 8 is compared in a fairly similar formulation to a mixture of cogranules of sodium carbonate and cogranules of BRITSIL H20 ® (of SiO₂ / _Na2 O ratio = 2 and containing 20% water - marketed by Philadelphia Quartz).

The results are shown in Table V.

It is found that the use of cogranules from Example 8 makes it possible to reduce the amount of sodium citrate (expensive) and polyacrylate (non-biodegradable).

Claims (27)

1. Use, as builder agent in a detergent composition, of an aqueous solution of alkali metal, especially sodium or potassium, silicate with a solids content of approximately 10-60 % by weight and with an SiO₂/M₂O molar ratio of the order of 1.6 to 3.5, containing at least 30 % of silicon atoms in Q₂ and Q₃ form, the Q₂ form meaning that each silicon atom participates in two -Si-O-Si- bonds, the remaining two bonds being an -Si-O-X end group where X is an alkali metal or H, and the Q₃ form meaning that each silicon atom participates in three -Si-O-Si- bonds, the remaining bond being an -Si-O-X end group.
2. Use according to Claim 1, characterized in that the solution of alkali metal, especially sodium or potassium, silicate, contains at least 50 % of silicon atoms in Q₂ and Q₃ form.
3. Process for the preparation of a builder agent, characterized in that a concentrated aqueous solution of an alkali metal silicate with an SiO₂/M₂O molar ratio of the order of 1.6 to 3.5 and exhibiting a solids content of the order of 10 to 60 %, containing at least 30 % of silicon atoms in Q₂ and Q₃ form, is adsorbed and/or absorbed by being brought into contact with an inorganic support which is inert towards silicate, the said support being other than sodium tripolyphosphate and being present in a quantity such that the quantity of water remaining associated with the said silicate after adsorption and/or absorption corresponds to a weight ratio of silicate expressed on dry basis/water associated with the silicate of the order of 100/120 to 100/40, the Q₂ form meaning that each silicon atom participates in two -Si-O-Si- bonds, the remaining two bonds being an -Si-O-X end group where X is an alkali metal or H, and the Q₃ form meaning that each silicon atom participates in three -Si-O-Si- bonds, the remaining bond being an -Si-O-X end group.
4. Process according to the preceding claim, characterized in that the support is chosen from sodium carbonate, sodium sulphate, sodium borate, sodium perborate, sodium metasilicate, or a phosphate such as trisodium phosphate, alone or as a mixture.
5. Process according to the preceding claim, characterized in that the said support is sodium carbonate.
   [lacuna]
6. Process according to one of Claims 3 to 5 , characterized in that the operation for bringing into contact is carried out by spraying the said concentrated silicate solution onto the support in particulate form at a temperature of the order of 20 to 95°C.
7. Process for the preparation of spherical cogranules of hydrated alkali metal silicates and of alkali metal carbonates characterized in that:

   - an aqueous solution based on alkali metal silicates containing at least 30 % of silicon atoms in Q₂ and Q₃ form or based on a mixture of the said silicates and alkali metal carbonates is sprayed onto a rolling bed of particles based on alkali metal carbonates travelling in a rotary granulating device, the speed of travel of the particles, the thickness of the rolling bed and the flow rate of the sprayed solution being such that each particle is converted into a plastic cogranule on coming into contact with other particles,

   - the cogranules obtained are subjected to a densification operation, and

   - the said densified cogranules are dried until a content of water associated with the silicate corresponding to a weight ratio of silicate expressed on dry basis/water associated with the silicate of the order of 100/120 to 100/40 is obtained,

   the Q₂ form meaning that each silicon atom participates in two -Si-O-Si- bonds, the remaining two bonds being an -Si-O-X end group where X is an alkali metal or H, and the Q₃ form meaning that each silicon atom participates in three -Si-O-Si- bonds, the remaining bond being an -Si-O-X end group.
8. Process according to Claim 7, characterized in that the sprayed aqueous solution based on silicate or silicate/carbonate mixture has a solids content of the order of 30 to 55 % by weight, the said alkali metal silicate exhibiting an SiO₂/M₂O molar ratio ranging from 1.6 to 3.5, the said carbonate being optionally present in proportions depending on the desired end product.
9. Process according to Claim 7 or 8, characterized in that the spraying of the solution based on silicate or silicate/carbonate mixture is carried out at a temperature of the order of 20 to 95°C.
10. Process according to any one of Claims 7 to 9 , characterized in that the particles forming the rolling bed are based on an alkali metal carbonate exhibiting:

    - an average diameter of the order of 10 to 150 10⁻⁶ m,

    - a non-bulk density of the order of 0.4 to 1.1 g/cm³,

    - a water content of the order of 0.05 to 0.4 %, and

    - a proportion of insoluble matter of the order of 5 to 100 mg/kg.
11. Process according to any one of Claims 7 to 10, characterized in that the particles forming the rolling bed contain less than 10 % of the weight of the cogranules of particles of a type other than an alkali metal carbonate and exhibiting a diameter and a density close to those of the alkali metal carbonate particles.
12. Process according to any one of Claims 7 to 11, characterized in that the granulating device is a rotary granulator permitting the onward movement of the particles as a thin layer.
13. Process according to Claim12 , characterized in that the rotary granulator is a coating pan.
14. Process according to any one of Claims 7 to 11, characterized in that the granulating device is a drum.
15. Process according to any one of Claims 7 to 14, characterized in that the carbonate-based particles travel at a temperature of the order of 15 to 200°C.
16. Process according to any one of Claims 7 to 15. characterized in that the quantities of solution based on silicate or silicate/carbonate mixture to be sprayed and of carbonate-based particles to be used correspond to a liquid flow rate/particle flow rate ratio which can range from 0.2 to 0.8 1/kg, these values being expressed as sodium salts.
17. Process according to any one of Claims 7 to 16, characterized in that the densification operation is carried out at ambient temperature by rolling the cogranules obtained in the granulation step in a rotary device.
18. Process according to Claim 17, characterized in that the densification operation is carried out in a rotary drum.
19. Process according to any one of Claims 7 to 18, characterized in that the cogranules obtained after densification are dried in a fluidized bed.
20. Process according to any one of Claims 7 to 19, characterized in that small quantities of liquid compounds commonly used in the detergency field are added, by spraying, to the cogranules obtained after drying.
21. Use of cogranules capable of being obtained by the process according to one of Claims 7 to 20 as a builder agent either in the preparation of a detergent composition or as a constituent component of a detergent composition.
22. Use according to Claim 21, characterized in that the detergent composition is a detergent powder composition for a dishwashing machine in a proportion of 3 to 90 % by weight of dry silicate with respect to the composition.
23. Use according to Claim 21, characterized in that the detergent composition is a detergent powder composition for a washing machine in a proportion of 3 to 60 % by weight of dry silicate with respect to the composition.