EP0437988B1 - Detergent additive based on polyphosphate and an active optical agent, method of its production and its use in detergent composition - Google Patents

Description

The present invention relates to a detergent compound based on polyphosphate, of a water-soluble alkali metal alkylsiliconate or of one of its water-soluble condensates and of an optically active water-soluble substance intended to be distributed uniformly over a room to be washed, as well as its preparation. It also relates to the detergent use of this compound.

Detergent compositions in the powder form in particular, contain, in addition to their usual constituents of the builders or surfactants type, numerous additives such as dyes, optical brighteners, photobleaching agents, softening agents, antiseptic agents, etc.

However, generally, these additives, which function by adsorption on the textile fibers, require a homogeneous distribution over the part to be washed. Indeed, if they are located in particular places on the article to be treated, there appears, at the end of the washing or after drying of it, colored spots or halos, which constitutes a disadvantage completely unacceptable and which also leads to a lowering of the expected performance of the product.

However, if these additives are directly incorporated into the washing powder, this homogeneous distribution is difficult to obtain given the very great risks of contact of the additive with the laundry before the powder is dissolved. This is particularly the case for hand washing in a bowl.

This case is in fact considered to be the most difficult, given the direct contact of the powder and the linen and the fact of the use of low volumes of water and washing habits favoring the dusting of the powder on the linen.

It is therefore essential to have a means allowing this homogeneous distribution.

In addition, incidentally and for commercial reasons, in the case of colored additives, it is sought to obtain a visual effect in the washing powder by the presence of colored grains. Thus these grains must be large enough not to give a uniform coloring of the washing powder. This last requirement increases the risk of localized distribution of the colored additive on the laundry.

Document FR-A-2 354 381 describes a detergent composition containing an anti-foaming substance consisting of a tripolyphosphate support, a polyorganosiloxane anti-foaming agent enclosed in a mixture of a water-insoluble wax and d an emulsifier insoluble in water.

Document EP-A-210 114 describes an anti-foaming substance comprising a support consisting of sodium tripolyphosphate and an acid orthophosphate and / or sodium acid pyrophosphate, and an anti-foaming composition consisting of an oil polyorganosiloxane and silica.

Document EP-A-57 088 aims to improve the storage of a detergency additive of the photoactivator, dye, fluorescent agent, bleaching activator type, by encapsulation of said additive in intimate mixture with a hydrated tripolyphosphate in a matrix. water-soluble glassy amorphous phosphate.

The main object of the invention is a means or a system making possible the homogeneous distribution of an optically active detergent additive on the article to be washed, this whatever the type of washing used.

A second object is the preparation of such a system.

For this purpose, the detergent compound according to the invention comprises a support constituted by an at least partially hydrated polyphosphate and at least one water-soluble optically active substance, and is characterized in that said optically active substance intended to be uniformly distributed over a part to be washed, is located at least partially inside said support, and in that said compound also contains a water-soluble alkali metal alkylsiliconate or one of its water-soluble condensates placed or adsorbed on the surface of said support.

Furthermore, the process for the preparation of the washing compound consists in mixing with the anhydrous or partially hydrated polyphosphate an aqueous solution comprising the above-mentioned substance and product.

• mélange du polyphosphate anhydre ou partiellement hydraté et de la substance précitée, puis addition d'eau audit mélange, cette eau pouvant au moins en partie être apportée sous la forme d'une solution aqueuse de ladite substance
• addition de l'alkylsiliconate au mélange résultant de l'étape précédente et addition éventuellement d'une quantité supplémentaire d'eau, cette eau pouvant au moins en partie être apportée sous la forme d'une solution aqueuse dudit siliconate.

According to a preferred variant of the invention, the process for preparing the detergent compound comprises the following steps:

• mixing of the anhydrous or partially hydrated polyphosphate and the aforementioned substance, then addition of water to said mixture, this water being able at least in part to be provided in the form of an aqueous solution of said substance
• addition of the alkylsiliconate to the mixture resulting from the preceding step and optionally addition of an additional quantity of water, this water possibly being at least partly provided in the form of an aqueous solution of said siliconate.

Finally, the invention relates to a detergent composition which is characterized in that it comprises a detergent compound of the above type or prepared by the process described above.

The detergent compound defined above ensures a delayed release of the additive, and thus makes it possible to reduce the risks of additive - laundry contact. It therefore provides a completely homogeneous distribution of this additive on the laundry and this even for hand washing in a bowl. In addition, this presentation of the additive makes it possible to impart a visual effect to the washing powder if necessary.

Other details and characteristics will appear better on reading the description which follows as well as concrete but nonlimiting examples relating to the implementation of the invention.

The detergent compound according to the invention therefore consists of three types of elements, namely an at least partially hydrated polyphosphate incorporating or supporting on the one hand, at least one water-soluble optically active substance intended to be uniformly distributed over a room to be washed (called in the rest of the description "the substance"), and on the other hand a product chosen from alkylsiliconates of water-soluble alkali metals or their water-soluble polycondensates, (called in the rest of the description "the product").

According to the invention, the detergent compound has the following particular structure:

The above-mentioned substance is located at least partly inside or at the heart of the polyphosphate-based support grain. The aforementioned product is located on the surface of said support or is adsorbed thereon.

The optimum embodiment is that for which all of the above substance is placed inside the polyphosphate grain and all of the above product on the surface thereof or adsorbed thereon. Of course, one can envisage any intermediate configuration without departing from the scope of the present invention, in which a part of the substance would be present on the surface of the polyphosphate.

Furthermore, the support based on polyphosphate can be composed of pyrophosphate or tripolyphosphate. However, in the context of the invention, it is preferred to use tripolyphosphate (TPP).

In addition, the polyphosphate of the compound according to the invention is at least partially hydrated, that is to say that it has a hydration rate of at least 8% by weight.

More particularly, this hydration rate is at least 10%, preferably at least 15% and in particular between 15 and 18%. This hydration results from the process for preparing the compound. As will be described later, it is this water of hydration which makes it possible to introduce the substance into the heart of the support.

Advantageously, the support must have a density of between 0.4 and 0.8 and preferably between 0.6 and 0.8.

Indeed, with a density greater than 0.8, polyphosphate and in particular TPP, in the form of particles, very difficultly absorbs water, which consequently hinders the introduction via water, of the substance at the heart of the particles, and that in sufficient quantity.

On the other hand, if the density of the support is less than 0.4, the compound is difficult to handle. In addition, it is advantageous to have a density of at least 0.6 in order to obtain a sufficient attrition resistance to avoid dusting of the compound according to the invention and consequently a uniform coloring of the washing powder.

As regards the particle size of the polyphosphate and in particular of the TPP, particles are generally used whose average size is between 200 μm and 800 μm, and preferably between 600 μm and 700 μm. This particle size is recommended to obtain the optical effect described above, when the aforementioned substance is colored.

Another preferred characteristic of the invention in the case of a TPP support is that it is in the form of phase 1.

Finally, it is preferred to use an alkaline polyphosphate. More particularly, the sodium TPP is retained as a support according to the invention.

Generally, the polyphosphate content is between 78 and 91.8% by weight, expressed as anhydrous polyphosphate and relative to the total weight of the detergent compound.

Another constituent of the detergent compound according to the present invention is the optically active water-soluble substance intended to be distributed uniformly over a part to be washed. It is understood that the compound of the invention can comprise several substances of this type at the same time. This substance can be chosen from the group of optical brighteners, photobleaching agents, and dyes.

Thus, in the group of optical brighteners, for cotton fabrics, polyamides and polyesters, mention may be made, by way of nonlimiting examples, of compositions of stilbene, triazole and benzidine-sulfone, in particular triazinyl-stilbene substituted with sulfonates, naphthotriazole- sulfonated stilbene or benzidine sulfone, the most preferred being combinations of stilbene and triazole.

et dont les atomes d'hydrogène portés par les carbones repérés 1 à 8 peuvent être substitués notamment par des atomes de Cl, Br et I.As photobleaching agents, mention may be made, among other things, of porphine derivatives but also the compounds described in French patent application FR-A- 2,564,481 in the name of RHONE-POULENC CHEMISTRY, the teaching of which is incorporated here in the present description and corresponding to the water-soluble salts or disels of the acid corresponding to the following general formula (1):

and whose hydrogen atoms carried by the carbons marked 1 to 8 may be substituted in particular by atoms of Cl, Br and I.

Among these products, there may be mentioned for example eosin "Yellow", but also 1,2-dibromo fluorescein, that is to say the dibromo salt or disel of formula (1), dibromo-3, 4 fluorescein, phloxine i.e. tetrabromo-1,2,3,4 tetrachloro-5,6,7,8 fluorescein, diodo-1,2 fluoresceine, diodo-3,4 fluorescein and tétraiodo-1,2,3,4 tétrachloro-5,6,7,8 fluoresceine or "Rose Bengal".

In the group of dyes which can be used as constituents of the washing compound according to the invention, there may be mentioned for example E 100 (curcumin), E 102 (tartrazine), E 120 (cochineal), E 123 (amaranth) , E 127 (erythrosine), E 131 (patent blue), E 132 (indigotine), E 140 (chlorophylls). More particularly, as a substance according to the invention, belonging to the group of photobleaching agents, it is possible to choose a derivative of tetrabenzo-tetraazoporphine.

As a derivative of this type which can also be used in the context of the invention, mention may be made of TINOLUX BBS from the company CIBA-GEIGY.

According to the invention, the content of optically active substance intended to be distributed uniformly of the aforementioned type for example is generally 0.1 to 2% by weight relative to the total weight of the detergent compound.

Finally, the detergent compound comprises a product chosen from water-soluble alkali metal alkylsiliconates and their water-soluble polycondensates.

These siliconates are well known products, they are salts of silicone acid or its derivatives.

• m est un nombre entier ou fractionnaire variant entre 0,1 et 3;
• M est un métal alcalin.

Mention may in particular be made of the products corresponding to formula (2)

R - Si (OM) _m (OH) _3-m (2)

and / or the condensation products thereof, formula in which R is an alkyl residue of 1 to 18 carbon atoms:

• m is an integer or fractional number varying between 0.1 and 3;
• M is an alkali metal.

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

More precisely, R can be a methyl, ethyl, propyl, butyl or isobutyl radical.

For M, mention may more particularly be made of sodium or potassium.

Likewise, sodium or potassium methylsiliconates are particularly used.

It should be noted that the alkali metal alkylsiliconates are products, most of which are commercially available.

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 US-A-2,441,422, US-A-2,441,423).

As an example of siliconates of this type available commercially, mention may in particular be made of RHODORSIL® SILICONATE 51T, marketed by the Applicant, which is a potassium methylsiliconate.

According to the invention, the content of supported siliconate is generally from 0.1 to 2% by weight relative to the total weight of the detergent compound.

We will now describe more precisely the process for preparing the detergent compound.

Firstly, according to a first variant, the polyphosphate, and in particular the TPP, anhydrous or partially hydrated, can be mixed in a single step with the aforementioned substance and product, at least one of these being provided in the form of an aqueous solution.

Another variant of the process according to the invention consists in preparing the detergent compound in two mainly stages.

In the first step, the polyphosphate, and in particular the TPP, anhydrous or partially hydrated, is mixed with the abovementioned substance and water is brought to this mixture for the hydration of the polyphosphate. We can do it by different methods.

We can first mix the polyphosphate and the substance and then add water to the mixture obtained.

According to a preferred method, the polyphosphate, the water and the substance are mixed at the same time. In the latter case, the substance can be brought in the form of an aqueous solution and it is this solution which at least partially provides the necessary water.

The water brought in at this stage penetrates into the polyphosphate grain and at the same time allows the introduction of the substance inside the grain itself.

The second step consists in adding the above-mentioned product to the mixture obtained previously. Here too, we can operate in several ways.

We can first of all simply mix the elements.

You can also mix and add water. This addition of water can be done after the dry mixing of the elements. Preferably, however, this addition is carried out simultaneously with the mixing. In this case, the product can be brought in the form of an aqueous solution which will thus provide the necessary water.

Furthermore, the amount of water used in the first step represents at least 50% of the water used entirely in the process for the desired hydration rate of the polyphosphate.

Advantageously, between each step, a maturing of each of the resulting mixtures is carried out. Such an operation ensures better diffusion of the water and of the constituents of the compound and promotes the crystallization of the water in the TPP particles thus treated. Ripening allows each mixture to cool because the hydration of TPP is an exothermic reaction. It is carried out by stirring each mixture obtained for a period of approximately 20 minutes in an atmosphere having a non-saturated vapor pressure.

Finally, the detergent compound according to the invention finds its application as a constituent in any detergent application, in particular compositions of the powder type.

In a manner known per se, these compositions can comprise a builder of the phosphate, polyphosphate, zeolite, silicate or carbonate type. They can also include surfactants, anionic, non-ionic, cationic, amphoteric. They can also include bleaching agents of the perborate type, foam control agents, anti-redeposition agents, fluorescent agents and all additives of the perfume, enzyme, sequestering, soluble polymer or color type, for example.

The content of detergent compound in a detergent composition is generally between 1 and 10% by weight.

Concrete examples will now be given.

EXAMPLES

First, some definitions and clarifications are provided below.

The mixing of the constituent elements of the compound was carried out thanks to the use of a laboratory mixer of 5 liters of useful capacity of LODIGE brand and of a laboratory sprayer.

The detergent powder was obtained by mixing 5% by weight of the compound according to the invention with a detergent reconstituted in the laboratory according to French standard NF C73171.

The coloring test was carried out according to the following procedure using standard cotton No. 405, marketed by Test Fabrics (USA):

It is deposited in the form of an accordion at the bottom of a plastic basin 50 g of already bleached fabric.

Then add 1 liter of city water at 30 ° C, hardness 17.9 ° French (a degree of French hardness is equivalent to 10 mg Ca CO ₃ / l), then press the fabric on the bottom of the basin to remove air bubbles. The water height above the fabric should be 2 cm.

For a period of 20 seconds, 5 g of washing powder containing 5% of the compound according to the invention are spread over the surface of the liquid.

After 1 minute, the fabric is removed from the basin, rinsed for 30 seconds under the tap with tap water, then wrung out.

Finally, cut the upper part of the fabric (20 x 20 cm) and dry at 150-160 ° with the iron.

Scoring of results

Spectrophotometric measurements

A white cotton sample is brought into contact on the one hand with an aqueous solution of TINOLUX BBS alone and on the other hand, with an aqueous solution of the detergent compound according to the invention, for 20 minutes at 35 ° C. The difference between the measurements carried out gives the quantity of TINOLUX BBS absorbed on the tissue, in% compared to the quantity fixed in the case of the Tinolux solution alone, which serves as a reference.

EXAMPLE 1

In a LODIGE Laboratory mixer, 1740 g of sodium TPP of the RHODIA PHOS G type marketed by RHONE-POULENC, of density = 0.75, are mixed with 20 g of TINOLUX BBS previously diluted in 120 g of water, by spraying this solution on the TPP.

A maturing step is then carried out with stirring for 20 minutes in an unsaturated atmosphere.

Then 20 g of SILICONATE 51T diluted in 100 g of water are then added to the mixture thus obtained by spraying. We end with a new period of ripening.

The staining test carried out under the conditions described above and with the compound thus prepared gives very good results because no stain appears on the treated tissue (note 1).

In addition, spectrophotometric measurements indicate that TINOLUX BBS is well fixed on cotton, and this at 85%.

COMPARATIVE EXAMPLE 2

This example highlights the essential role of the product supported in the compound according to the invention.

1960 g of sodium TPP of the same type as in Example 1 are mixed with a solution comprising 20 g of TINOLUX BBS and 20 g of water. We then proceed to the ripening stage.

The same staining test, but carried out with the compound of this example 2, gives very poor results since the tissue is heavily stained with colored spots (note 5).

Claims (17)

1. Washing compound comprising a support consisting of an at least partially hydrated polyphosphate and at least one water-soluble optically active substance, characterized in that the said optically active substance, intended to be distributed uniformly on an article to be washed, is situated at least partially within the said support, and in that the said compound contains, in addition, a water-soluble alkali metal alkylsiliconate or one of its water-soluble condensates placed on the surface of the said support or adsorbed on the latter.
2. Washing compound according to the preceding claim, characterized in that the polyphosphate has a degree of hydration of at least 8%.
3. Washing compound according to one of the preceding claims, characterized in that the polyphosphate has a density of between 0.4 and 0.8, and preferably between 0.6 and 0.8.
4. Washing compound according to one of the preceding claims, characterized in that the polyphosphate has a particle size of between 200 and 800 µm, and preferably between 600 and 700 µm.
5. Washing compound according to one of the preceding claims, characterized in that the polyphosphate is a pyrophosphate or a tripolyphosphate.
6. Washing compound according to one of the preceding claims, characterized in that the polyphosphate used is a tripolyphosphate in phase 1 form.
7. Washing compound according to one of the preceding claims, characterized in that the polyphosphate is an alkali metal tripolyphosphate, and in particular sodium tripolyphosphate.
8. Washing compound according to one of the preceding claims, characterized in that the optically active substance is chosen from the group comprising optical brightening agents, optical bleaching agents and colorants.
9. Washing compound according to Claim 8, characterized in that the abovementioned substance chosen from among the optical bleaching agents is a tetrabenzotetraazoporphin derivative.
10. Washing compound according to one of the preceding claims, characterized in that the content of the abovementioned substance is between 0.1 and 2% by weight relative to the total weight of the compound.
11. Washing compound according to one of the preceding claims, characterized in that the alkali metal alkylsiliconate is a sodium or potassium methylsiliconate.
12. Washing compound according to one of the preceding claims, characterized in that the content of the abovementioned alkylsiliconate is between 0.1 and 2% by weight relative to the total weight of the compound.
13. Process for preparing the washing compound according to one of Claims 1 to 12, characterized in that it consists in mixing the Anhydrous or partially hydrated polyphosphate with the abovementioned substance and abovementioned alkylsiliconate, at least one of these latter being introduced in the form of an aqueous solution.
14. Process for preparing the washing compound according to one of Claims 1 to 12, characterized in that it entails the following steps:

    a) the anhydrous or partially hydrated polyphosphate and the abovementioned substance are mixed and water is introduced into the said mixture, it being possible for this water to be introduced at least partially in the form of an aqueous solution of the said substance;

    b) the abovementioned alkylsiliconate is added to the mixture resulting from the previous step and an additional amount of water is optionally introduced, it being possible for this amount to be introduced at least partially in the form of an aqueous solution of the said siliconate.
15. Process according to Claim 14, characterized in that a maturing is performed at the end of each of the abovementioned steps a) and b).
16. Process according to Claim 14 or 15, characterized in that at least 50% of the water used in the process is introduced during step a).
17. Detergent composition, characterized in that it comprises a washing compound of the type according to Claims 1 to 12 or of the type prepared by the process according to Claims 13 to 16.