WO2000043117A1

WO2000043117A1 - Concentrated or dilutable solutions or dispersions, preparation method and uses

Info

Publication number: WO2000043117A1
Application number: PCT/FR2000/000118
Authority: WO
Inventors: Jean-Marc Angeli; Alfred Testa
Original assignee: Arcane Industries
Priority date: 1999-01-21
Filing date: 2000-01-20
Publication date: 2000-07-27
Also published as: FR2788703A1; ATE263620T1; FR2788703B1; DE60009657D1; EP1144102B1; EP1144102A1

Abstract

The invention concerns a composition in the form of a micro-emulsion or solution of a concentrated and dilutable active agent, characterised in that it as clear as water and essentially consists of (a) at least 10 % of a hydrophobic active agent with a KB (Kauri butanol) index not less than 30 or an N-alkyl pyrrolidone; and (b) a glycol ether or a mixture of two glycol ethers, and in the latter case the first glycol ether having a HLB higher by 0.8 than the second glycol ether.

Description

Concentrated and dilutable solutions or dispersions, preparation process and applications

The present invention relates to new concentrated and dilutable solutions or dispersions, their preparation process and their applications.

Many active liquid agents in various fields are effective but cannot be used as such. Indeed, taking into account their too strong pure efficacy, they must be used diluted, for example in the form of emulsions for a liquid active agent. But then there is the problem of their recovery and reprocessing, especially if they have harmful effects on the environment. Traditionally, the dispersion of an organic solvent in an aqueous continuous phase to produce an emulsion requires the use of surfactants of emulsifying nature, hydrotropic agents such as xylene-, toluene-, or sodium cumene sulfonate, and the more often a third polar solvent such as isopropanol or glycol ethers. By way of illustration, a conventional micro-emulsion of terpenic solvent has the following typical composition: water / polyoxethylenated fatty alcohols / polyoxethylenated nonylphenols / sodium xylene sulfonate / isopropanol / terpenic solvent. Its lifespan is limited, as is its resistance to temperature. It can therefore only be used cold. Conventionally, microemulsions are obtained by gradually adding, with stirring, an aqueous phase to an organic phase (or vice versa), in the presence of a surfactant, and if necessary a third solvent.

It would therefore be desirable to have homogeneous compositions, which are easy to produce, do not require the addition of thermal energy by heating and are easily recyclable. Microemulsions are homogeneous compositions, but they contain significant concentrations of formulating agents, in particular emulsifiers and hydrotropic agents.

It would also be desirable for these stable microemulsions to be obtained with the minimum of components other than water and the active agent to be emulsified.

WO-A-91/00893 describes paint and varnish removers possibly containing water and being in the form of gels or supports impregnated on organic clays such as bentones. These compositions involve at least 10% of a third water-soluble solvent of N-methyl pyrrolidone type.

Now after long research, the applicant has discovered with astonishment that new compositions in the form of solutions or dispersions of the concentrated microemulsion type or of a hydrophobic active agent or of an N-alkyl pyrrolidone with water corresponding to The above criteria could be obtained simply by the sole use of a glycol ether or preferably a mixture of two glycol ethers.

This is why the present application relates to a composition in the form of a liquid / liquid dispersion of the microemulsion type or solution of an active agent, concentrated and dilutable with water, characterized in that it is clear as water and that it essentially comprises at least 10% by weight of a hydrophobic active agent having a KB index (Kauri butanol) greater than or equal to 30 and preferably 40 or less than 10% of an N -alkyl pyrrolidone and - a glycol ether or preferably a mixture of two glycol ethers, in the latter case the first glycol ether having an HLB greater than 0.8, preferably 0.9 and very particularly 1.0 to that of the second glycol ether.

In the present application and in what follows, the term “essentially” means at least 90% by weight of the composition, preferably at least 95% and very particularly at least 98%. By "hydrophobic" is meant that the active agent has a low solubility in water. The solubility in water of the active ingredient (s) will preferably be less than or equal to 8%, in particular less than or equal to 6%, particularly less than or equal to 4%, very particularly less than or equal to 1%.

When the composition is a microemulsion, it is for example water in oil (W / O), in particular "multiple" (O / W / O or W / O / W), and particularly oil in water (O / W) .

In what follows when we speak of microemulsion, we also aim at solutions except when the context shows that only microemulsions can be targeted.

When only one glycol ether is used, it will have a high HLB. Particular use is made of the methyl ether of dipropylene glycol. When two glycol ethers are used, the methyl ether of dipropylene glycol is used in particular as the first glycol ether.

In decreasing order of HLB value calculated by the Davies method, there may be mentioned for example the methyl ether of dipropylene glycol (8,2), the n-propyl ether of propylene glycol (7,3), the ether n -propyl of dipropylene glycol (7.2), the n-butyl ether of propylene glycol (6.9).

The glycol ethers may represent, for example, 50% to 90% by weight of the concentrated microemulsion, in particular 60% to 90%, and very particularly 70% to 90%.

When two glycol ethers are used, the ratio of the first glycol ether to the second glycol ether may range, for example, from 1: 8 to 4: 5, in particular from 1: 5 to 3: 5, and very particularly from 1 : 3 to 2: 5 by weight.

The active agent having a KB index preferably greater than or equal to 30 and in particular to 40 will be chosen from fatty substances, terpene derivatives of synthetic, semi-synthetic or natural origin, rectified or not (by distillation) such as essential oils of pine, citrus terpenes, especially orange such as d-limonene, solvents non-water-soluble organic substances of petroleum origin aliphatic, including isoparaffinics, certain carboxylated derivatives, such as esters such as dimethylesters, certain amides, carbonylated derivatives such as certain ketones, certain aldehydes, polar solvents other such as terpene alcohols, alcohols fatty (therefore high molecular weight), thiols, certain amines, and ethers comprising for example from 4 to 15 carbon atoms, preferably from 5 to 14 carbon atoms, in particular from 7 to 13 carbon atoms.

The active agent will preferably be chosen from citrus terpenes, in particular orange; d-limonene is particularly retained.

The active agent will most particularly be d-limonene, a mixture of RPDE dimethylesters or their mixture.

There may still be an active agent used in cosmetics as a moisturizer such as evening primrose oil, a soothing and healing as aliantoïne, a UV agent such as phenoxyethanol or Mexoryl ^®, an anti-aging agent such as retinol, retinaldehyde, vitamin A acid, an exfoliating agent, an antioxidant agent or an active pharmaceutical agent usable in dermatology such as a corticosteroid.

The N-alkyl pyrrolidone is preferably N-methyl pyrrolidone. It is obvious to those skilled in the art that in the present application when we speak of "a" given product, we must understand "at least one" product considered when the context justifies it. This is the case for example for the active agent which can be a mixture of active agents, or for the emulsifiers. The above microemulsions or solutions may also comprise one or more conventional additives chosen, for example, from additives soluble in a non-aqueous phase such as perfumes, and preservatives such as formaldehyde or parabens. These may be used in the usual proportions in the case of microemulsions, in particular less than 5%, particularly from 0.1% to 3%, and very particularly from 0.1% to 2% by weight. The additive can also be a preparation of dimethyl amides of unsaturated fatty acids such as that marketed under the name DMAD or BUSPERSE ^® 47 by the company BUCKMAN.

The addition of the above microemulsions or solutions makes it possible to confer particular properties on them, such as biocidal properties. They can be made completely water-soluble by adding surfactants of emulsifying nature such as those marketed by the RHODIA Company under the name Rhodoclean HP and / or ASP (alkoxylated fatty alcohols, derivatives of pine terpenes) and Rhodasurf T-50 ( ethoxylated fatty alcohol) or using an amino ether oxide.

The present application also relates to a microemulsion or concentrated solution above, characterized in that it is diluted so that the diluent phase such as an isoparaffinic solvent and in particular an aqueous phase represents up to 99% by weight of the microemulsion or dilute solution, in particular up to 80%, preferably up to 60%, particularly up to 50%, very particularly up to 40%.

The present application also relates to a process for the preparation of a microemulsion or concentrated solution above, characterized in that the active agent or liquid active agents and the glycol ethers or ethers are mixed with stirring to emulsify or dissolve them.

Although this preparation can be done hot, it has the remarkable advantage of being able to be carried out at room temperature and quickly, in a few minutes of stirring, for example using a stirrer with 1 or 2 propellers, that is, the process requires a minimum of energy.

However, a non-liquid active agent should be melted or dissolved beforehand to pass into liquid form.

The present application also relates to a process for the preparation of a dilute microemulsion, characterized in that the diluent, the glycol ethers or ethers and the active agent or liquid active agents to be emulsified are stirred . The mixing order is not critical. In preferential conditions of implementation, a premixture of the diluent, of the glycol ethers or ethers is mixed with stirring, then the active agent or liquid active agents to be emulsified are added gradually with stirring. By adding "progressively" is meant for example adding 10% VΛ per minute. The diluent is in particular water or an aqueous phase. It is also in particular an isoparaffinic solvent. It can also be a non-water-soluble aromatic organic solvent such as petroleum solvents of the white spirits type.

A microemulsion or dilute solution can also be prepared by diluting a microemulsion or concentrated solution above.

In this case, the glycol ethers may represent, for example, 15% to 85% by weight of the diluted microemulsion, in particular 20% to 80%, particularly 25% to 70%, and very particularly 30% to 50%. .

When it is present, the aqueous phase preferably consists of water, in particular demineralized water. When the latter is not demineralized, the aqueous phase preferably further comprises a softening agent such as a phosphonate or the tetrasodium salt of ethylene diamine tetraacetic acid. For example, for tap water of medium hardness, the softening agent may represent around 0.5% by weight of the composition.

The aqueous phase can also contain, if desired, one or more water-soluble compounds such as dyes.

To prepare traditional micro-emulsions of solvents in water, it is necessary to adjust each of the constituents according to the concentration of the solvents. Among the other remarkable qualities of the compositions according to the invention, it should be noted that when two glycol ethers are used, the simple adjustment of the content of second glycol ether makes it possible to vary the content of agent (s ) active. It is thus possible in particular to manufacture microemulsions with different contents of active agent (s) without having to design each time a particular formulation, that is to say without having to do vary several parameters of nature and quantity of substances in the formulation.

The compositions of the invention also exhibit high rinsability with water, in particular active agents which are not by nature, and / or a possibility of aqueous dilution and separation of phases adjustable at will and predetermined.

The microemulsions or solutions according to the invention are easily recyclable. After use, a simple aqueous dilution makes it possible to reduce the volume of non-aqueous effluents to be treated. The used solution or microemulsion quickly separates into two distinct phases, one of which is a non-aqueous phase. During the phase separation, the glycol ethers are distributed within each phase to facilitate the transfer and solubilization of the respective impurities and contribute to the clarity of the interface.

The system according to the invention has total reversibility. The non-aqueous phase may be filtered and / or rectified for recycling. The simple addition of methyl ether of propylene glycol and water will recreate the initial product.

This recycling can be repeated several times

Thanks to the use of glycol ether (s) according to the invention, it is possible to obtain, even with the same composition of the remainder of the formula, microemulsions of active agents of chemical nature and also different polarity. than d-limonene and mixtures of dimethylesters.

These properties are illustrated below in the experimental part.

The microemulsions of the invention make it possible to produce an excellent surface preparation of the mechanical parts before mounting or applying a protective coating. They can be used on most metals, alloys, plastic materials and elastomers, especially for exterior maintenance of aircraft.

They make it possible to prepare compositions which have excellent chemical harmlessness with respect to seals and sensitive materials. (polycarbonates, EPDM). After use, they leave a non-greasy surface state, without impurity or residual film.

It is also possible to adjust the rate of evaporation of the solvents used as active agents which, generally, maintain a flash point above 61 ° C; this increases with the content of diluent phase, in particular water. This gives performances of the same order as those obtained with the halogenated solvents of the prior art, but without their harmful effects on the environment.

These properties justify the use of micro-emulsions or solutions of the invention as industrial solvent, cleaner - renovator or surface treatment for plastics such as garden furniture, as cleaner - renovator for stained wood. or blackened, cleaner for polyurethane foam. They also justify the use of the microemulsions or solutions of the invention for eliminating putty residues, cleaning brushes, removing glues and adhesives and diluting all paints. They still find their use in boating (washing wood, plastics, mechanical elements, ...) as long as they are rinsable with sea water unlike detergents, or even, for those involving a N-alkyl pyrrolidone, in pickling. They also find their use in the maintenance and renovation of painted facades, roofs, cladding, aluminum and wood joinery, the elimination of certain graffiti in the building, the cleaning of pedestrian streets, market places, public places, trucks and household waste containers, street furniture in roads, exterior washing of vehicles and boats, maintenance of textiles, for example cloths, work clothes, particularly operating drapes, sails, floor coverings, carpets and rugs, stripping and defluxing of printed circuit boards in electronics. They also find their use in printing especially for cleaning screens, especially silk. This is why the subject of the invention is also washing or pickling agents which comprise a diluted microemulsion of the invention or microemulsion or concentrated solution defined above.

The preferential conditions for implementing the solutions, microemulsions and concentrates described above also apply to the other objects of the invention referred to above.

The following examples illustrate the present application.

EXAMPLES 1 to 3 Diluted microemulsions corresponding to the formula were prepared:

Mixture of dimethylesters sold by the company RHODIA under the name RPDE (glutarate, succinate, and dimethyl adipate).

The above microemulsions were prepared as follows:

While maintaining constant stirring, the methyl ether of dipropylene glycol is very gradually incorporated in demineralized water, in 5 minutes, until the mixture is clear. Always maintaining constant agitation, the mixture of RPDE dimethylesters or d-limonene is incorporated. Stirring is continued for 5 minutes and the homogeneity of the microemulsion is checked, for example by observing its transparency. It is observed that the use of 25% by weight of the methyl ether of dipropylene glycol alone makes it possible to emulsify from 2 to 10% of mixture of RPDE dimethylesters. The use of 80% of this ether alone makes it possible to emulsify from 2 to 10% of d-limonene. Water represents 100% by weight in both cases.

EXAMPLES 4 to 6

Diluted microemulsions corresponding to the formula were prepared:

These microemulsions were prepared in the following manner: While maintaining constant stirring, very gradually incorporated into demineralized water, over 5 minutes, the methyl ether of dipropylene glycol and the n-butyl ether of propylene glycol . Always maintaining constant agitation, the mixture of RPDE dimethylesters or d-limonene is incorporated. Stirring is continued for 5 minutes and the homogeneity of the microemulsion is checked, for example by observing its transparency.

It is observed that a composition containing 27% of methylpropylene glycol ether and 10% of n-butyl ether of propylene glycol makes it possible to emulsify from 2% to 20% of mixture of RPDE dimethylesters without having to make an adjustment of formula other than water qs 100% by weight. It is also observed that a stable microemulsion containing 15% of mixture of RPDE dimethylesters is obtained by using a mixture of 26% dipropylene glycol methyl ether with 5 to 15% propylene glycol n-butyl ether . Water here also represents qs 100% by weight.

It is also observed (see examples 3 and 6) that a stable micro-emulsion according to the invention of 10% d-limonene containing 5 to 20% water can be prepared using in the first case 85%% d 'methyl ether of dipropylene glycol and in the second case 45% of this glycol and 25% of n-butyl ether of propylene glycol.

EXAMPLES 7 and 8

Concentrates for microemulsion corresponding to the formula have been prepared:

These microemulsions were prepared by mixing in 5 minutes, until the mixture is clear, the methyl ether of dipropylene glycol and the n-butyl ether of propylene glycol, then, while maintaining constant stirring, the mixture of RPDE dimethylesters. The mixture is stirred again for 5 minutes and the homogeneity of the microemulsion is checked.

After diluting 1/1 of Example 7 with water, the diluted microemulsion of Example 5 is obtained if desired with 11.0% of propylene glycol n-butyl ether.

The microemulsion of Example 8 is dilutable in all proportions, in particular in water.

EXAMPLES 9 to 12 As indicated in Examples 1 to 3, dilute microemulsions corresponding to the formula were prepared:

The last line of the table represents the quantity of aqueous phase, for example of water, from which a release of the organic phase is caused, as well as the capacity of the microemulsions to absorb, for example water, that is, to be diluted.

EXAMPLE 13: Relarαaαe test

For example with regard to Example 6, 100 g of the original microemulsion (representing 100% by weight) having then been used for degreasing automotive mechanical parts, when 40 ml of water are added with the micro-emulsion of soiled origin, agitates then leaves to stand, the appearance of a cloudiness is observed, witnessing the loss of the homogeneity of the composition, then there is a phase shift in two clear superposed phases with a very clear separation at the interface. The hydrophilic phase represents 92 ml for 65.3 ml at the start. Since 40 mL of water was added, about 80% of the starting hydrophilic phase was therefore recovered. The properties of the compositions of the invention therefore make it possible to have to treat only a reduced volume of liquid. In addition, a very large proportion of organic upper phase (n-butyl ether of propylene glycol and d-limonene) can also be recovered for the preparation of a new starting microemulsion.

With an original microemulsion composed of water (40%), methyl ether of dipropylene glycol (24%), n-butyl ether of propylene glycol (15%), mixture of RPDE dimethylesters (21%), recovered approximately 95.5% of the starting hydrophilic phase by adding 40 ml of water.

EXAMPLES 14 to 18 Diluted microemulsions corresponding to the formula were prepared as indicated in Examples 1 to 3:

^* Ex. 14: 10% mixture of RPDE or d-limonene dimethylesters

This example 14 shows that thanks to the use of glycol ether (s) according to the invention, a microemulsion of active agents of chemical nature and polarity as different as d-limonene and mixtures is obtained. of dimethylesters.

EXAMPLE 19

A microemulsion corresponding to the formula of Example 18 was prepared but by replacing the mixture of RPDE dimethylesters with a mixture of 5% of said mixture of RPDE dimethylesters and 5% of d-limonene.

Claims

1. A composition in the form of a liquid / liquid dispersion of microemulsion type or solution of an active agent, concentrated and dilutable, characterized in that it is clear as water and that it consists essentially at least 10% by weight of a hydrophobic active agent having a KB index (Kauri butanol) greater than or equal to 30 or less than 10% of an N-alkyl pyrrolidone and - of a glycol ether or a mixture of two glycol ethers, in the latter case the first glycol ether having an HLB greater than 0.8 than that of the second glycol ether.

2. A concentrated composition according to claim 1, characterized in that the active agent is a hydrophobic active agent having a KB index greater than or equal to 40.

3. A concentrated composition according to claim 1 or 2, characterized in that it comprises a mixture of two glycol ethers.

4. A concentrated composition according to one of claims 1 to

3, characterized in that it is in the form of micro-emulsion.

5. A concentrated composition according to one of claims 1 to

4, characterized in that it comprises, as glycol ether, methyl ether of dipropylene glycol.

6. A concentrated composition according to claim 5, characterized in that it comprises, as second glycol ether of n-propyl ether of propylene, n-propyl ether of dipropylene glycol or n-butyl ether propylene glycol.

7. A composition according to one of claims 1 to 6, characterized in that it comprises 50% to 90% by weight of ether or glycol ethers.

8. A composition according to one of claims 1 to 6, characterized in that it is diluted so that the diluent phase represents up to 99% by weight of the microemulsion or diluted solution.

9. A process for the preparation of a concentrated composition as defined in one of claims 1 to 7, characterized in that the active agent or liquid active agents and the glycol ethers are ethically mixed. to emulsify or dissolve them.

10. A washing or pickling agent which comprises a concentrated or diluted composition as defined in one of claims 1 to 8.