EP0637626A1 - Use of siliconates in automatic dishwashing detergent compositions - Google Patents

Abstract

Use of siliconate or of its derivatives in a detergent composition for a dishwasher, as antifoaming agent. The invention also relates to a product characterised in that it includes siliconate or its derivatives, alkali metal silicate supported on alkali metal carbonate and water associated with the silicate, the ratio of water associated with the silicate to the silicate, expressed on a dry basis, being higher than or equal to 33/100. It also relates to a detergent composition for a dishwasher including the abovementioned product.

Description

The present invention relates to the use of siliconate in a detergent composition for dishwashers as an anti-filming agent.

It also relates to new products, possibly in the form of cogranules, based on siliconate, alkali metal carbonate, alkali metal silicate and water associated with the silicate.

Finally, it relates to a new detergent composition comprising the products indicated above, and preferably without sodium tripolyphosphate.

The problem of filming forming during washing is well known in the field of washing dishes in the machine. Indeed, this phenomenon is particularly visible on translucent glass, for which one observes, after one or more washes, a formation of continuous haze or more or less dispersed stains which makes the glass opaque.

These veils or stains correspond to a more or less adherent precipitation deposit of materials mainly consisting of calcium salts and possibly dirt. The deposition of calcium salts can be largely avoided or removed by a special treatment thanks to specific detergent formulations. Laundry workers thus seek to optimize detergent compositions, and more specifically detergent compositions without tripolyphosphate.

Thus, it has been proposed for detergent compositions without tripolyphosphate to add sequestering agents, such as citric, gluconic, phosphonic, tartaric acid and the corresponding salts, and / or water-soluble polymers, optionally biodegradable, such as polyacrylic acids, acrylic-maleic or -vinyl copolymer acids. Despite this addition in detergent compositions without tripolyphosphate, the phenomenon of appearance of veils or stains remains and is more important in this type of detergent compositions without tripolyphosphate than those with tripolyphosphate.

The main object of the invention is therefore to propose a solution to the problem of sails or stains formed during the automatic washing of the dishes.

Another object of the invention is to provide a detergent composition devoid of sodium tripolyphosphate, while having a formation of haze and stains during washing negligible and comparable to that of detergent compositions comprising sodium tripolyphosphate.

These and other aims are achieved by the present invention which in fact relates to the use of siliconate or its derivatives in a detergent composition for dishwashers as an anti-filming agent.

The term “anti-filming agent” is understood to mean, according to the invention, an agent eliminating the veils or stains formed during washing on the dishes and / or preventing their formation.

The use of siliconate or its derivatives does not reduce the detergent nature of the other compounds present in a detergent composition.

This use can have the economic advantage of being able to reduce the quantity of organic sequestering agents, in particular sodium citrate, the price of which is relatively high.

Siliconates are well known products, they are salts of siliconic acid or its derivatives.

Mention may in particular be made of the products corresponding to the following formula (1):

R-Si (OM) _m (OH) _3-m (1),


and / or the condensation products thereof, formula in which R is a hydrocarbon residue generally of 1 to 18 carbon atoms, optionally substituted by a hydrogen atom, an amino group, ether, ester, epoxy, mercapto, cyano, polyglycol; m is a real number varying from 0.1 to 3; M is an alkali metal, an ammonium or phosphonium group, or an alkaline earth.

Preferably, R is a hydrocarbon residue of 1 to 10 carbon atoms and more particularly of 1 to 6 carbon atoms.

More specifically, R can be an alkyl radical, for example methyl, ethyl, propyl, butyl, isobutyl; an alkenyl radical, for example vinyl; an aryl radical, for example phenyl or naphthyl; an arylalkyl radical, for example benzyl or phenylethyl; an alkylaryl radical, for example tolyl, xylyl; or an araryl radical such as biphenylyl.

For M, there may be mentioned more particularly sodium or potassium, as well as the groups N⁺R'₄ and P⁺R'₄, in which R ', identical or different, represent hydrocarbon residues of 1 to 6 carbon atoms .

More particularly, alkaline siliconates are used.

Likewise, particular use is made of alkylsiliconates and in particular alkaline alkylsiliconates, for example sodium or potassium methylsiliconates.

It is also possible to use the siliconates of formula (1) in which R is a vinyl or phenyl radical, and more particularly the alkali siliconate of this type.

It should be noted that most of the alkali or alkaline earth siliconates are commercially available.

The siliconates are usually sold in the form of aqueous solutions.

They can be prepared for example by hydrolysis of the corresponding silanes having 3 hydrolyzable groups such as halogen atoms, alkoxy radicals, followed by dissolution of the product obtained in a solution of a strong inorganic base in proportions such as there is at least one equivalent in base per atom of silicon (see for example the patents US 2,441,422 and US 2,441,423).

As an example of commercially available siliconates of this type, mention may in particular be made of Rhodorsil Siliconate 51T®, sold by the Applicant, which is a solution of approximately 50% of dry extract of potassium methylsiliconate.

By products derived from siliconates is meant here the condensation products of the products corresponding in particular to formula (1) described above, or those resulting from the at least partial polymerization of silicone compounds or polymers.

It is known, for example, that the alkali metal alkylsiliconates can be transformed into polyalkylsiloxanes, in particular by the action of carbon dioxide or other acidifying agent.

It goes without saying that, in the context of the present invention, it is possible to use in combination two or more siliconates or derivatives.

There is no limit to the amount of siliconate or its derivatives to be used. It is however generally between 0.5 and 20% by weight (quantities expressed on a dry basis relative to the total weight of the detergent composition). Preferably, this amount is between 1 and 5%.

The siliconates can be introduced in various ways into the detergent composition. Thus, the siliconate (or its derivatives) can in particular be added to the detergent composition at the end of preparation of the formulation of the detergent composition, in particular by spraying; it can be added in a dry appearance by simple mixing with the other constituents of the composition detergent; the siliconate can also be added to another liquid compound introduced during the manufacture of the detergent composition.

For example, when the siliconate is added to another liquid compound introduced during the manufacture of the detergent composition, it can be added to a silicate solution, the mixture of the two will be shaped subsequently.

When the siliconate is added in a dry appearance to the detergent composition, the dry appearance of the siliconate can in particular be obtained by absorption and / or adsorption of the siliconate solution on an inorganic support (chemically) inert with respect to the siliconate .

Mention may in particular be made, as mineral support inert (chemically) with respect to the siliconate, an amorphous silico-aluminate, sodium sulphate, sodium carbonate, sodium borate, sodium metasilicate, phosphates , tripolyphosphates or even other products which will be detailed below, these supports can be used alone or as a mixture.

The mineral support that is inert (chemically) with respect to the siliconate is preferably water-soluble.

The amount of support depends on its adsorbent and / or absorbent capacity and, of course, on the amount of siliconate to be rendered in a dry appearance. However, the product used according to the invention as a support can have other functions in the detergent composition, it can be, in this case, present in amounts greater than those necessary to support the siliconate solution.

Preferably, the siliconate solution (or its derivatives) used is introduced during the formulation of the detergent composition in a form adsorbed and / or absorbed on an inorganic support (chemically) inert with respect to the siliconate.

As a support, use is preferably made of amorphous silico-aluminate and even more preferably agents based on alkali metal silicate supported on alkali metal carbonate and water associated with said silicate, the water ratio associated with silicate / silicate expressed in sec being greater than or equal to 33/100.

These agents are described in the European patent application published on June 3, 1992 under the number 0 488 868 and in the European patent application whose number is 93400359.1, both having been filed by the Applicant. These agents, which can be in the form of spherical cogranules, are in particular characterized by their preparation process which consists in: (a) spraying an aqueous solution based on alkali metal silicate or based on a mixture of silicate and carbonate of alkali metal on a rolling bed of particles based on alkali metal carbonate or based on the identical silicate-carbonate mixture mentioned above, traveling in a rotary granulation device, the speed of movement of the particles, the thickness of the rolling bed and the flow rate of the sprayed solution being such that each particle is transformed into a plastic cogranule by coming into contact with other particles, (b) drying, optionally, said cogranules obtained in (a), these steps being implemented so that the weight ratio of water associated silicate / silicate expressed as dry remains greater than or equal to 33/100, preferably 36/100.

Preferably, between steps (a) and (b), the cogranules are subjected to a densification operation.

The term water associated with the silicate is understood to mean the water of said aqueous solution which is not combined with carbonate, in particular which is not in crystallized form.

Mention may therefore be made, by way of example of agents based on silicate and carbonate as described above, of Nabion ™ manufactured and marketed by Rhône-Poulenc.

The siliconate solution can be added to these agents by any means known per se. It can in particular be added by spraying, optionally followed by air drying. This addition of siliconate (including possible drying) is carried out in a controlled manner so that the minimum water content associated with the silicate indicated above is respected.

Thus, the subject of the present invention is also a product for a detergent composition, characterized in that it comprises siliconate or its derivatives and an agent based on alkali metal silicate supported on alkali metal carbonate and based on water associated with said silicate, the water ratio associated with silicate / silicate expressed as dry being greater than or equal to 33/100.

This product can be a substituent in detergent compositions of tripolyphosphate, since it has in particular a so-called softening effect on the water used for washing. Generally, the softening of water is carried out by elimination of the calcium and magnesium present in the water in the form of soluble and in the soils in more or less soluble complex forms. This product also has an anti-filming effect during washing.

This product preferably consists essentially of siliconate or its derivatives and of the above-mentioned agent.

It can be obtained by the general process which consists in (1) implementing the process for the preparation of the agents, in the form of co-granules, as globally described above and disclosed in the European patent application published on June 3, 1992 under No. 0 488 868 and in the patent application European whose number is 93400359.1, (2) spraying the solution of siliconate or its derivatives on the cogranules thus obtained and (3) possibly drying.

This drying step is only carried out if the product obtained after step (2) has a tacky appearance. Of course, this drying step is carried out in a moderate manner, in particular in air, so that the minimum water content associated with the silicate indicated above is respected.

The upper limit of the water weight ratio remaining associated with silicate / silicate expressed in dry corresponds to the limits for which a silicate is kept in powder form with fluid flow ("free flowing"), that is to say usable in detergency. To fix the ideas, the water weight ratio remaining associated with the silicate / silicate expressed in dry matter should preferably be less than or equal to approximately 120/100.

The maximum amount of siliconate or its derivatives present in this product corresponds to the limit of the adsorbent and / or absorbent power of the agent, as described above. However, to fix the ideas, the maximum limit of adsorption and / or absorption of an agent based on alkali metal silicate supported on alkali metal carbonate and water associated with silicate, the water ratio associated with silicate / silicate expressed as dry being greater than or equal to 33/100, is generally situated around 15, preferably 13%, of the total weight of this agent.

The minimum quantity of siliconate or of its derivatives present in this product preferably corresponds to 2% of the total weight of the product, and more advantageously to 3%.

The carbonate present in this product preferably represents from 45 to 75% of the dry weight of silicate and carbonate present. More advantageously, it represents from 50 to 70% of this dry weight.

These products, according to the invention, are used in detergent compositions in such a way that the minimum water content associated with the silicate indicated above is respected. They are used in detergent compositions for dishwashers generally at a rate of 3 to 90% by weight, preferably from 3 to 70% by weight, of said compositions (these amounts are expressed by weight of dry silicate relative to the weight of the composition).

The amorphous alkali metal silico-aluminate capable of being used as a siliconate support, according to the invention, is a product well known per se and can be obtained by the general process which consists in mixing, preferably with stirring, an alkali metal silicate solution and an alkali metal aluminate or aluminum sulfate solution, metal hydroxide alkaline can optionally be added, this mixture gels or precipitates, it is then filtered, washed and dried by any means known per se.

The amorphous alkali metal silico-aluminate preferably used in the present invention has the general formula (1): x M₂O, y Al₂O₃, z SiO₂, w H₂O, formula in which M represents an alkali metal, preferably sodium , x is between 0.2 and 2, y is equal to 1, z is between 0.2 and 15 and w belongs to the positive reals different from 0. More particularly, we use the amorphous silico-aluminate of formula (1 ) in which x is between 0.8 and 1.2, z is between 8 and 15 and w is between 0.3 and 9.

It is preferred that the amorphous silico-aluminate used according to the invention has a calcium exchange capacity greater than or equal to 50 mg of CaCO₃ / g of anhydrous silico-aluminate and / or has an absorbent capacity greater than 100 ml / 100 g, preferably greater than 150 ml / 100g ("DOP" intake, ISO 787/5 standard).

Thus, there may be mentioned, by way of examples, the Tixolex 25 and 28® manufactured and marketed by Rhône-Poulenc.

Besides the products for detergent composition for dishwashers described above, there is also present in the detergent composition at least one surfactant in an amount which can range from 0.5 to 10%, preferably of the order of 1 at 5%, by 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 (alcoyl - sulfosuccinates 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 alcoyldiméthyl- bétaïnes.

Among these surfactants, there may be mentioned:

• 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 (alkyl - C₁₂ - C₁₆ 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.

• des "builders" du type:
  • . phosphates à raison d'au moins 25 % du poids total de formulation,
  • . acide nitriloacétique jusqu'à environ 10 % du poids total de formulation,
  • . acide citrique, acide gluconique ou acide tartrique ou leurs sels jusqu'à environ 50 % du poids total de formulation,
• 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-incrustation, anti-voile ou anti-tâche du type copolymères d'acide acrylique et d'anhydride maléïque ou des homopolymères d'acide acrylique 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.

Various constituents can also be present in the detergent composition, such as:

• "builders" like:
  • . phosphates at a rate of at least 25% of the total weight of the formulation,
  • . nitriloacetic acid up to approximately 10% of the total formulation weight,
  • . citric acid, gluconic acid or tartaric acid or their salts up to approximately 50% of the total weight of the formulation,
• bleaching agents of the perborate, percarbonate, chloroisocyanurate, N, N, N ', N'-tetraacetylethylenediamine (TAED) type up to around 30% of the total weight of said detergent composition,
• anti-encrustation, anti-fog or anti-stain agents of the acrylic acid and maleic anhydride copolymer type or acrylic acid homopolymers 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 composition.

Thus, the present invention finally covers a new detergent composition for a particularly interesting dishwasher which is characterized in that it comprises siliconate or its derivatives, alkali metal silicate supported on alkali metal carbonate, and water. associated with silicate, the water associated with silicate / silicate ratio expressed as dry being greater than or equal to 33/100; therefore, characterized in that it advantageously comprises products as described above.

Preferably, this detergent composition is devoid of sodium tripolyphosphate.

The following examples illustrate the invention without, however, limiting its scope.

In all of the following or the foregoing, all percentages are given by weight, unless otherwise stated.

EXAMPLES EXAMPLE 1

• . teneur en carbonate (en poids) = 55 %
• . teneur en silicate (en poids) = 29 %
• . teneur en eau (en poids) = 16 %

A co-granule manufactured and marketed by Rhône-Poulenc under the brand Nabion ™ is used. It consists of sodium silicate supported by sodium carbonate and has a water associated with silicate / silicate ratio expressed as dry equal to about 55 / 100. This agent has the following general composition:

• . carbonate content (by weight) = 55%
• . silicate content (by weight) = 29%
• . water content (by weight) = 16%

It has a bulk density of 0.85 g / cm3 and an average diameter of 700 μm.

This cogranulate is obtained according to the process described in European Patent Application No. 0 488 868; it is more particularly obtained by a process analogous to that described in Example 8 of this patent application.

A solution of Rhodorsil 51 T® is sprayed under pressure on this cogranulate at a rate of 10% relative to the total weight.

The product obtained is dry in appearance, the dry siliconate extract represents 5% by weight of the total weight of the product thus obtained, the total water content of this product is approximately 18%.

This product is then added by mixing in a LODIGE M5G® to additives in order to obtain a composition for dishwashers. This composition is given in the following table (1).

This composition is compared with a composition called a "control" composition comprising the same cogranulate, but without siliconate.

These compositions are tested in a MIELE G 560® automatic household dishwasher with a short program at 65 ° C with a final hot rinse and drying.

With each composition used at 4 g / liter of water, there is a sequence of 10 cumulative washes / dryings of soda-lime glass plates of 20 cm x 20cm which are initially perfectly clean. To perform these tests, the water softener is not regenerated; therefore the water used has a total hardness of 30 ° French TH and a calcium film will appear on the glass plates over the washings.

The plates are then subjected to a photometric measurement using a GARDNER® device.

The total amount of light L returned by the sample is thus 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 results are collated in the following table (1). COMPOSITION WITNESS EXAMPLE 1 Nabion ™ (%) 45 0 Nabion ™ + Rhodorsil 51T® (10%) (%) 0 50 sodium citrate (%) 25 25 sodium polyacrylate (MW = 4500) (%) 3 3 sodium sulfate (%) 11 6 perborate (%) 11 11 TAED (%) 2 2 enzymes (%) 1 1 nonionic surfactants% 2 2 L 7.4 5.8 Table (1)

EXAMPLES 2 TO 8

The procedure is exactly as in Example 1, the conditions for introducing the siliconate are mentioned in the following table (2).

The dishwasher is the MIELE G 595® model with a short program at 67 ° C.

The detergent compositions are indicated in table (2), the compositions according to the invention are compared with a detergent composition comprising sodium tripolyphosphate (TPP) (comparative example 2) and with detergent compositions not comprising siliconate (comparative examples 3 and 7). COMPOSITIONS (%) ex. 2 ex. 3 ex. 4 ex. 5 ex. 6 ex. 7 ex. 8 Nabion ™ 45 45 45 45 Nabion ™ + Rhodorsil 51T® (6%) 45 45 TPP 45 citrate 25 25 25 25 30 30 polyacrylate (PM 4500) 3 3 3 3 5 5 Rhodorsil 51T® 5 Rhodorsil 51T® / Tixolex 28® 10 sodium sulfate 39 11 6 1 11 4 4 various 16 16 16 16 16 16 16 dry siliconate (%) 0 0 2.5 3 1.35 0 1.35 water hardness (° TH) 28 25 29 27 30 32 27 L 4.02 7.83 6.40 6.57 5.52 5.23 4.76 Table (2)

In this table :

• "Rhodorsil 51T®" corresponds to the introduction of siliconate by spraying at the end of preparation of the detergent composition
• "Rhodorsil 51T® / Tixolex 28®" corresponds to a siliconate solution adsorbed and / or absorbed on amorphous silico-aluminate, the amount of each corresponding to a Rhodorsil 51T® / Tixolex 28® weight ratio of 60/40.
• "miscellaneous" corresponds to the following constituents: perborate, TAED, enzymes and nonionic surfactants;
• "dry siliconate" corresponds to the total amount of dry siliconate present in the detergent composition

It is noted that the results of filming test of the detergent compositions according to the invention, devoid of TPP, can be comparable to those of a detergent composition comprising TPP.

EXAMPLES 9 TO 19

The procedure is exactly as in Example 1, the conditions for introducing the siliconate are mentioned in the following table (3).

The detergent compositions are indicated in table (3), the compositions according to the invention are compared with a detergent composition comprising sodium tripolyphosphate (TPP) (comparative example 9) and with detergent compositions not comprising siliconate (comparative examples 10, 13 and 17).

• "cogranulé dont 5% Rhodorsil 51T®" correspond à du Rhodorsil introduit avec la solution de silicate lors de la fabrication du cogranulé;
• "Rhodorsil 51T®" correspond à l'introduction de siliconate par pulvérisation en fin de préparation de la composition détergente
• "Rhodorsil 51T®/Tixolex 28®" correspond à une solution de siliconate adsorbée et/ou absorbée sur du silico-aluminate amorphe, la quantité de chacun correspondant à un rapport pondéral Rhodorsil 51T®/Tixolex 28® de 60/40.
• "divers" correspond aux constituants suivants : perborate, TAED, enzymes et tensio-actifs non-ioniques;
• "siliconate sec" correspond à la quantité totale de siliconate sec présent dans la composition détergente

In this table :

• "cogranulate of which 5% Rhodorsil 51T®" corresponds to Rhodorsil introduced with the silicate solution during the manufacture of the cogranulate;
• "Rhodorsil 51T®" corresponds to the introduction of siliconate by spraying at the end of preparation of the detergent composition
• "Rhodorsil 51T® / Tixolex 28®" corresponds to a siliconate solution adsorbed and / or absorbed on amorphous silico-aluminate, the amount of each corresponding to a Rhodorsil 51T® / Tixolex 28® weight ratio of 60/40.
• "miscellaneous" corresponds to the following constituents: perborate, TAED, enzymes and nonionic surfactants;
• "dry siliconate" corresponds to the total amount of dry siliconate present in the detergent composition

It is noted that the results of filming test of the detergent compositions according to the invention, devoid of TPP, can be comparable to those of a detergent composition comprising TPP.

Claims (18)

1 / Use of siliconate or its derivatives in a detergent composition for dishwashers as an anti-filming agent. 2 / Use according to claim 1, characterized in that the siliconates or their derivatives are products corresponding to the following formula (1):

R-Si (OM) _m (OH) _3-m (1),

and / or the condensation products thereof, formula in which R is a hydrocarbon residue generally of 1 to 18 carbon atoms, optionally substituted by a hydrogen atom, an amino group, ether, ester, epoxy, mercapto, cyano, polyglycol; m is a real number varying from 0.1 to 3; M is an alkali metal, an ammonium or phosphonium group or an alkaline earth 3 / Use according to the preceding claim, characterized in that R is a hydrocarbon residue of 1 to 10 carbon atoms and more particularly of 1 to 6 carbon atoms. 4 / Use according to any one of the preceding claims, characterized in that the siliconates are chosen from alkaline siliconates. 5 / Use according to the preceding claim, characterized in that the siliconates correspond to sodium or potassium methylsiliconates. 6 / Use according to any one of the preceding claims, characterized in that the amount of siliconates or their derivatives is between 0.5 and 20% by weight in the detergent composition. 7 / Use according to any one of the preceding claims, characterized in that the siliconates or their derivatives are added either to the detergent composition at the end of preparation of the formulation of the detergent composition, in particular by spraying; either in a dry appearance by simple mixing with the other constituents of the detergent composition; either one other liquid compound introduced during the manufacture of the detergent composition. 8 / Use according to the preceding claim, characterized in that the siliconate adsorbed and / or absorbed on a mineral support inert with respect to the siliconate is added by simple mixing with the other constituents of the detergent composition. 9 / Use according to the preceding claim, characterized in that the support is an amorphous silico-aluminate or an agent based on alkali metal silicate supported on alkali metal carbonate and water associated with the silicate, the water ratio associated with the silicate / silicate expressed as dry being greater than or equal to 33/100. 10 / Use according to the preceding claim, characterized in that the support is an agent based on alkali metal silicate supported on alkali metal carbonate and water associated with silicate, the water associated with silicate / silicate ratio expressed as dry being greater than or equal to 33/100. 11 / Product, characterized in that it comprises siliconate or its derivatives and an agent based on alkali metal silicate supported on alkali metal carbonate and based on water associated with said silicate, the water ratio associated with silicate / silicate expressed as dry being greater than or equal to 33/100. 12 / Product according to the preceding claim, characterized in that the water ratio associated with silicate / silicate expressed as dry is less than or equal to 120/100. 13 / Product according to one of claims 11 or 12, characterized in that the maximum amount of siliconate or its derivatives present in this product corresponds to 15, preferably to 13%, of the total weight of said agent. 14 / Product according to one of claims 11,12 or 13, characterized in that the minimum amount of siliconate or its derivatives present in this product corresponds to 2% of the total weight of said product, and advantageously to 3%. 15 / Product according to any one of claims 11 to 14, characterized in that the carbonate present in this product represents from 45 to 75% of the dry weight of silicate and carbonate present, and preferably from 50 to 70%. 16 / Detergent composition for dishwasher, characterized in that it comprises at least one product according to any one of claims 11 to 15. 17 / detergent composition according to claim 16, characterized in that the product represents 3 to 90% by weight, preferably 3 to 70%, by weight of said composition. 18 / Composition according to one of claims 16 or 17, characterized in that it is devoid of sodium tripolyphosphate.