RU2542993C2 - Bicontinuous microemulsion detergent composition - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to field of detergent compositions, in particular highly active compositions of liquid detergents, intended in addition to other applications, for cleaning in laundries and/or household conditions. described are compositions of bicontinuous detergent microemulsions, which contain surface active system, water solution and oil or solvent, and additionally described are sprayer, device for preliminary stain removal and method of microemulsion preparation.

EFFECT: provision of fast dissolution of solid fatty material (dissolution of oil/fatty stains).

12 cl, 9 tbl, 5 ex

Description

FIELD OF THE INVENTION

The invention relates to the field of detergent compositions, in particular highly active liquid detergent compositions intended for washing, inter alia, in laundries and / or households. The compositions of the present invention relate to the field of microemulsions, in particular bicontinuous microemulsions.

State of the art

Liquid detergent compositions are widely recognized and are now preferred by many consumers in the markets of developed countries, as well as developing, and in emerging markets. Such liquid detergent compositions are primarily used in laundry and household applications.

One of the most common problems is the removal of grease stains and / or stains, especially stains and / or stains of hard or hardened fat. This problem is inherent in the household area (for example, cleaning kitchen surfaces, washing dishes) and the washing and washing areas (for example, cuffs and collars).

Liquid detergent compositions are widely known in these fields. Typically, liquid detergent compositions contain an active surfactant and a solvent. In addition, liquid detergent compositions may contain flavoring agents, fillers, polymers, bleaches, thickeners, fluorescent substances and other conventional detergent ingredients. Liquid detergent compositions are often subjected to structuring, for example, actions to control fluid viscosity or improve stability and prevent phase separation or provide the ability to include ingredients that are not soluble in water.

One form of a stable liquid detergent composition is an emulsion detergent composition. A specific type of emulsion is microemulsion. In general, emulsions are opaque liquids that do not look preferable in the eyes of the modern consumer. Microemulsions can be prepared transparent and typically also have a lower viscosity. WO 95/27034 discloses detergent compositions in the form of oil-in-water microemulsions that provide quick stain removal. Composition WO 95/27034 contains a surfactant system containing short chain nonionic alcohol ethoxylates having less than 12 carbon atoms and at least 45% C10 material. It was found that such oils in aqueous microemulsions do not provide sufficient dissolution of grease stains and contaminants when applied in pure form. It remains desirable to quickly solubilize the fat (or oil contaminants) when applied pure to a grease stain or contamination to dissolve, among other things, sebum on the collars of the shirt and grease on solid surfaces.

Microemulsions have also been disclosed in a number of other documents, such as US Pat. No. 5,415,812, which discloses an easy-to-use detergent composition; or US Pat. No. 4,438,009, which discloses pre-laundry treatment compositions containing low amounts of solvents.

Other pretreatment compositions have been proposed, mainly in the field of washing and cleaning fabrics, in order to ensure stain removal.

US 4,561,991 discloses compositions in the form of microemulsions for pre-laundry treatment. Mixtures of polyamines and fat-removing solvents are disclosed. Other surfactants, such as nonionic surfactants, are also disclosed.

US Pat. No. 5,891,836 discloses a microemulsion composition providing good fat removal and containing a surfactant alkyl ether sulfate, a nonionic surfactant, fatty acid amines and solvents.

A liquid detergent composition that removes contaminants and / or stains of hardened fatty material during a basic wash under neutral pH conditions remains desirable.

An object of the present invention is to provide a composition that provides rapid dissolution of solid fatty material.

Another objective of the invention is to provide a stable concentrated detergent composition containing up to 90% surfactant.

Another objective of this invention is to provide a transparent concentrated detergent composition.

Another objective of the invention is the provision of a concentrated detergent composition showing rapid dissolution in water.

Another objective of the invention is to provide a concentrated detergent composition having a low viscosity.

Another objective of the invention is to provide a composition of liquid detergent, which provides quick dissolution of oil / grease stains or contaminants when it is used in its pure form.

It has been unexpectedly found that a bicontinuous microemulsion washing composition containing a short-chain non-ionic surfactant provides a concentrated liquid detergent composition that removes stains and / or stains of solid or hardened fatty material when doing basic washing at a neutral pH.

Summary of the invention

Accordingly, the present invention provides a bi-continuous microemulsion detergent composition containing 40-90 wt.% Surface-active system containing: 10-50 wt.% Surface-active system of a linear or branched fatty alcohol having 5-8 carbon atoms, or a product condensation of a linear or branched fatty alcohol having 5-8 carbon atoms and containing no more than 5 alkylene oxide groups, and mixtures thereof, as well as a surfactant, 5-30 wt.% aqueous solution containing: aqueous electrolyte, characterized in that the aqueous solution has an ionic strength of 0.1-4 mol / l, 5-30 wt.% oil or solvent, characterized by a Hansen solubility index between 14 and 20 (MPa) ^0.5 , having a solubility in oil of a solid fatty substance trilaurin more than 3 wt.% and, in addition, characterized in that the viscosity of this composition is less than 1000 MPa · s (25 ° C and 20 s ^-1 ).

In yet another aspect, the invention provides a method for preparing a microemulsion comprising the following sequence of steps: adding a surfactant system to an oil / solvent, mixing them with an overhead stirrer, adding possible hydrophobic ingredients, adding an aqueous phase containing electrolytes.

Although the examples in this application mainly illustrate applications in laundries, it is noted that applications related to domestic cleaning, including hard surfaces, dishwashing, etc., and applications related to fabric conditioning are also included in the scope of this application .

These and other aspects, features and advantages will be apparent to those of ordinary skill in the art upon reading the following detailed description and the appended claims. In order to avoid ambiguous interpretation, any feature of any one aspect of the present invention may apply to any other aspect of the present invention. The word “comprising” is intended to mean “including,” but not necessarily “consisting of” or “composed of”. In other words, the steps or options enumerated are not required to be exhaustive. It is noted that the examples presented in the following description are intended to illustrate the invention and are not intended to limit the invention in any way to these examples per se.

Similarly, unless otherwise indicated, all percentages represent mass percentages. With the exception of working and comparative examples or explicitly indicated otherwise, all the numerical indicators in this description, determining the quantities of substances or reaction conditions, physical properties of materials and / or applications, should be understood as being changed using the word "about". Numerical ranges expressed in the format "from x to y" are understood as including the values of x and y. When preferred constituent ranges are described for a particular feature in the x-to-y format, it is understood that all ranges combining the various endpoints are also considered.

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to a bicontinuous microemulsion detergent composition.

Bicontinuous microemulsion

A bi-continuous microemulsion has a microstructure of oil and water channels penetrating the sample (filling the sample) in contrast to the discrete distribution of droplets found in oil-in-water (oil / water) and / or water-in-oil microemulsions (water / oil). These oil or water channels filling the sample interact equally well with hydrophobic or hydrophilic contaminants on the substrates and contribute to the speedy solubilization of contaminants / dirt, especially solid oil or grease stains or contaminants. These structures can be characterized by various known experimental techniques, including conductivity, viscosity, light scattering, SAXD (small angle X-ray diffraction), SANS (neutron small angle scattering), and NMR self-diffusion studies.

The surface tension at the oil-water interface is the lowest in this structure compared to oil / water or water / oil microemulsions. Due to the channels filling the sample, the viscosity of the bicontinuous microemulsion is usually higher than that of the corresponding oil / water or water / oil microemulsions.

Bicontinuous microemulsion also has a higher ability to solubilize additional ingredients in the emulsion than oil / water or water / oil microemulsions.

The binocular microemulsions of the invention are typically Newtonian fluids. When shearing, their viscosity usually does not decrease.

Surface active system

The compositions of the present invention comprise from 40 to 90 wt.% Of a surfactant system, preferably at least 45 wt.%, More preferably at least 50 wt.% Or even at least 60 wt.%.

Highly active compositions even more preferably contain at least 50 wt.%, More preferably at least 60 wt.%, Or even at least 70 wt.% Of the surfactant system.

Other liquid detergent or fabric cleaner compositions, fabric softener compositions, and household detergent compositions (eg, dishwashing compositions) preferably contain no more than 80 wt.%, More preferably no more than 70 wt.%, Even more preferably no more 60 wt.% Or even not more than 50 wt.%.

The surfactant system of compositions of the present invention contains a linear or branched fatty alcohol or a condensation product of a linear or branched fatty alcohol and alkylene oxide (e.g. ethylene oxide and / or propylene oxide), preferably ethylene oxide (also known as ethoxylated fatty alcohol or alcohol ethoxylate ) A linear or branched fatty alcohol contains from 5 to 8 carbon atoms. When the fatty alcohol is alkoxylated, the number of alkylene oxide groups is not more than 5, preferably between 1 and 4. Ethylene oxide (EO) groups are most preferred.

A linear or branched fatty alcohol or alkoxylated fatty alcohol is present in the composition with respect to the surfactant system in a concentration of from 10 to 50 wt.%, Preferably at least 15 wt.% Or even at least 20 wt.% relative to the surfactant system, but preferably in a concentration of not more than 40 wt.%, more preferably not more than 35 wt.% or even not more than 30 wt.% with respect to the surfactant system.

Additional surfactant

The surfactant system also contains an additional surfactant. In general, such surfactants may be selected from the surfactants described in such well-known manuals as “Surface Active Agents”, Volume 1, Schwartz & Perry, Interscience 1949, Volume 2 , Schwartz, Perry & Berch, Interscience 1958, and / or the current edition of McCutcheon's Emulsifiers and Detergents, published by Manufacturing Confectioners Company, or Tenside-Taschenbuch, H. Stache, 2nd edition, Carl Hauser Verlag, 1981.

Such surfactants include anionic surfactants, cationic surfactants, nonionic surfactants, zwitterionic surfactants and / or amphoteric surfactants and mixtures thereof.

Anionic and nonionic surfactants are most preferred in fabric and fabric detergent compositions, while any surfactant can be used in household cleaning products.

In dishwashing liquids, anionic and nonionic surfactants and combinations thereof are most preferred. Hard-surface aerosol cleaners (spray and wipe) can use any surfactant.

Hard water resistant surfactants are particularly preferred, such as alkyl ether sulfates (e.g. SLES - sodium lauryl sulfate), alkoxylated nonionic surfactants, alkanolamides and AOS (alpha olefin sulfonates).

Oil or solvent

The composition also contains from 5 to 30 wt.% Oil or solvent, characterized by the presence of a Hansen solubility index between 14 and 20 (MPa) ^0.5 and solubility of solid triglyceride fatty substances in oil and / or solvent more than 3 wt.%.

Hansen's solubility index is at least 15 (MPa) ^0.5 , more preferably at least 16 (MPa) ^0.5 and usually not more than 19 ((MPa) ^0.5 or even not more than 18 (MPa) ^0.5 .

Preferably, the solubility in oil of the solid fatty substance trilaurin (triglyceride) is more than 5% or even more than 10%. These percentages refer to the total amount of oil and / or solvent and trilaurin dissolved in it.

The oil is preferably selected from essential oils, oils based on fatty acids, mono-, di- and triglycerides, polyester derivatives of sugars and sucrose polyesters, as well as terpenes.

Preferred essential oils are those derived from plant sources, for example citronella, orange peel, lemon sorghum oil, lemon verbena, neem oil (Azadirachta indicd), etc. Preferred fatty acids are C8-22 fatty acids, including di- and tricarboxylic acids and oligomeric fatty acids (such as those sold under the brand name Pripol 1017 (manufactured by Unichema)). Also preferred are mono-, di- and triglycerides, including those medium chain length glycerides that are liquid at ambient conditions. Preferred terpenes are limonene, eugenol and terpineol.

The solvent is preferably selected from fatty acid alkyl esters and / or fatty alcohols, preferably obtained from renewable sources such as palm, coconut, soybeans, with a C7 to C22 fatty acid chain length distribution and an ester group 1-22 chain length distribution .

Combinations of any of these oils and / or solvents are also included within the scope of the invention.

The melting point of said fatty acid ester is preferably below 40 ° C, more preferably below 10 ° C and most preferably below 5 ° C.

When biodegradability is not required, other contemplated solvents and oils may be linear and / or branched alkanes.

Water solution

The composition contains 5-30 wt.% An aqueous solution having an ionic strength of from 0.1 to 4 mol / L, preferably at least 0.2 mol / L or even at least 0.5 mol / L, but preferably not more than 3.5 mol / L or even not more than 3 mol / L.

The aqueous composition contains water and an electrolyte. The electrolyte is usually present in the composition in such a concentration that the ionic strength of the solution is within the above range. Typically, the electrolyte is present in a concentration of up to 15% by weight with respect to the aqueous solution when the electrolyte is a monovalent electrolyte salt. The amount needed depends on the type of electrolyte used and its valency.

Without claiming theoretical depth, it was found that the requirements for the electrolyte correspond to the Schulze-Hardy rule for colloidal solutions, which determines the necessary amount based on the required concentration of a monovalent electrolyte, divided by a valence index in the 6th degree; for example, when 15% NaCl is required to create a microemulsion, it can be replaced with CaCl ₂ at a concentration of about 15% / 2 ⁶ = 15% / 64 = 0.23%.

Preferably, monovalent electrolytes are present in a concentration of between 1 and 15% with respect to the aqueous solution.

Divalent electrolytes are preferably present at a concentration between 0.01 and 4% with respect to the aqueous solution.

Trivalent and multivalent electrolytes are preferably present at a concentration of between 0.005 and 2% with respect to the aqueous solution.

Preferred electrolytes are citrates, halides (preferably chlorides), phosphates, sulfates and sulfites of alkali metals and alkaline earth metals; other suitable electrolytes are aluminum chloride and iron chloride, as well as mixtures of any of the above compounds. Hydroxosols are not preferred due to the adverse effect on pH and the possibility of undesired reactions.

Possible ingredients

The composition may also contain a filler, anti-redeposition components, mosquito and / or insect repellents, tinting pigments, bactericidal additives (oil-based), oil-soluble bleach, oil-soluble fluorescent substance, enzymes, flavoring agents and dirt-repellent polymers.

The bleach is preferably in the form of an organic peracid (eg, PAP - phthalimidopercapaproic acid) and is usually included in the compositions in amounts of up to 10 wt.%, Preferably up to 8 wt.%, More preferably up to 5 wt.%; usually between 0.5 and 4% or even between 1 and 2 wt.%. The whitening ingredient preferably has low solubility in water (less than 200 ppm at 30 ° C), but high solubility (more than 0.5 wt.%) In oil / solvent. The whitening ingredient is preferably dissolved in the oil / solvent phase of the bicontinuous microemulsion. The whitening ingredient is believed to act on contamination during the interaction of oil droplets with contaminated substrates. If bleach is included, the pH of the composition for reasons of stability is preferably in the range from acidic to neutral; the preferred pH is in the range of 5-7.

Mosquito repellent ingredients such as lemon verbena oil, citronella oil, lemon sorghum oil and mixtures thereof may be included in amounts up to 30% by weight. Mosquito repellents have been demonstrated on shirts laundered with compositions containing at least 6% by weight of any of the above components and mixtures thereof.

Flavoring agents may be included in the composition at a concentration of between 0.1 and 5% by weight. Typically, the concentration is less than 3%, even less than 2%; in most cases, the flavoring substance is present in a concentration between 0.5 and 1 wt.%. It has been shown that the inclusion of flavoring substances in a microemulsion provides up to 10 times better application of them on tissues, and flavoring substances are stored for a longer time in comparison with a surfactant solution containing an equivalent amount of flavoring substances.

Viscosity

The viscosity of the composition is preferably low. By low is meant a viscosity of not more than 1000 MPa · s, more preferably not more than 500 MPa · s, preferably less than 300 MPa · s, even more preferably less than 200 MPa · s, or even less than 150 MPa · s. Preferably, the composition has a viscosity above 5 MPa · s, more preferably above 10 MPa · s, even more preferably above 20 MPa · s or even above 50 MPa · s. All the mentioned viscosity indices were measured using a Cammed CSL-100 viscometer with standard conical geometry at a speed of 20 s ^-1 and 25 ° С.

pH

The pH is preferably in the neutral region in the range of 5 to 9, preferably at least 6 and not more than 8. If necessary, any known pH adjusting agents or buffering agents can be used. The pH of the composition containing the bleaching peracid is preferably between 5 and 7.

Way

The microemulsion is preferably prepared by sequentially adding a surfactant system to the oil / solvent, mixing them with each other using an overhead stirrer, optionally adding hydrophobic ingredients such as fluorescent substances, essential oils / flavoring agents; the addition of an aqueous phase containing electrolytes, and the addition of enzymes / bleaches.

Additional hydrophobic ingredients include fluorescent substances, flavoring agents and water-insoluble dirt-repellent polymers (for example, Gerol is a trademark of Rhodia).

Ingredients such as bleaches, enzymes, water-soluble dirt-repellent polymers (sodium carboxymethyl cellulose), are usually added to the composition only after the formation of microemulsions.

Product format

Laundry detergents can be packaged in standard bottles. Dry cleaning products are usually packaged in metering devices, such as stain remover pens, ball stain removers, brush pens and / or aerosol spray devices (such as sprinklers or squeezable spray bottles). Household cleaning products are usually in the form of sprinklers. Dishwashing liquids are usually offered in bottles.

The invention is further illustrated by the following non-limiting examples.

Examples

The binocular microemulsions of the present invention are compared in their characteristics to similar compositions that are not in the form of microemulsions, and to the commercially available concentrated liquid detergent compositions.

In all compositions, all concentrations are presented as mass percent relative to the total weight of the composition.

Example 1. A method of manufacturing a microemulsion detergent composition

Sodium-LAS (linear sodium alkylbenzenesulfonate, Unilever) was mixed with ethoxylated alcohol (Imbentin OA / 030, C ₈ EO ₃ , 100%, clear liquid). Mixing was performed using a high speed homogenizer (at 14,000 rpm for 15 minutes). After homogenization of the first two ingredients was completed, sodium laureth sulfate (3 EO) (SLES, Galaxy surfactants, Mumbai, India) was added. Water containing dissolved fluorescent substance, electrolytes (NaCl, Na ₂ CO ₃ , etc.) and enzymes was added to the mixer. Stirring was continued until a homogeneous liquid solution was obtained. An oil / solvent d-limonene (99%, Sigma) was added to the mixer at lower revolutions (2000 rpm). A low viscosity, transparent / translucent product was obtained. The process temperature was maintained at 25 ° C.

According to the method described above, two compositions were prepared (Composition 1 and Comparative Composition A, see table below).

Ingredient Composition 1 (wt.%) Composition A (wt.%) Na-LAS 26 26 SLES 22 22 C8-EO3 * 16 C9-11-EO3 * 16 d-limonen eighteen eighteen Water 16.8 16.8 NaCl 1,2 1,2 Composition Colorless, transparent microemulsion Liquid crystal, opaque Viscosity (MPa · s) 300 > 10,000 *) Nonionic surfactant represented by ethoxylated alcohol.

Example 2. The effectiveness of the cleaning (volume wash)

Lined fabrics (cotton (C), polycotton (PC), polyester (PE)) 10 × 10 cm in size were contaminated with a mixture of trilaurin and carbon black (1000: 1, ultrasonic homogenization) in a hot (80 ° C) state without using any solvents. For each sample 10 × 10 cm was applied 200 μl.

The fabrics were soaked for 30 minutes in a washing solution containing water and 1.2 g / l microemulsions (composition 1), or in the washing liquid of Comparative Composition A. Water hardness was 6 ° fH. Then the fabrics were washed for 15 minutes in a tergotometer filled to 300 ml at 25 ° C, 90 rpm, the liquid: fabric ratio = 30, and washed twice with water with a hardness of 6 ° fH twice for 2 minutes. After which the samples were dried.

Before washing and after drying with a Macbeth Color-Eye spectrophotometer at a wavelength of 460 nm (UV Exclusive SCI), the reflectance of the samples was measured. The value of reflectivity is presented as a percentage of reflected light at a specified wavelength. The cleaning efficiency was determined as the difference (dR) between the reflectivity before and after washing (dR460 = R _before -R _after ); the higher the dR value, the better the cleaning.

Cleaning efficiency in water with a hardness of 6 ° fH.

Cleaning system dR460 * Cotton Polycotton Polyester Composition 1 20.5 14.9 twenty Comparative composition A 10.6 eleven 3,7

Similar experiments were performed in water with a hardness of 48 ° fH instead of 6 ° fH.

Cleaning efficiency in water with a hardness of 48 ° fH.

Cleaning system dR460 * Cotton Polycotton Polyester Composition 1 16,4 19.9 16 Comparative composition A 11.9 12.7 6.5

Findings. The efficiency of cleaning contaminants containing solid fat using 1.2 g / l of microemulsion exceeds the efficiency of an equivalent solution of a surfactant.

Example 3. The cleaning efficiency (volume wash) in comparison with a commercially available product

A comparison was made of the microemulsion of Composition 1 with a commercially available concentrated liquid detergent composition (Comparative Composition B, Persil Small & Mighty, Unilever, UK).

Comparative Composition B Concentration (wt.%) Nonionic Alcohol Ethoxylate (C 12-15 EO7) twenty LAS Acid 13 SLES-3EO 5 Fatty Acid (Prifac 5908) 4,5 Lemon acid one NaOH 3 Monopropylene glycol 9 Glycerol 5 Triethanolamine 3 Minor ingredients (flavoring agents, fluorescent substances, enzymes, opacifiers, exfoliating substances) four Water Brought to 100%

All concentrations relate to the overall composition.

In order to be able to make a representative comparison between concentrated microemulsion and a less concentrated industrial product, the samples were washed with a washing solution containing 1.2 g / l of microemulsion (Composition 1) or 2.0 g / l of industrial product (Comparative Composition B), respectively.

Contamination of desiccated tissues (C, PC, and PE) was performed, as in Example 2.

The fabrics were soaked for 30 minutes in a washing solution containing the above concentration of surfactant in water with a hardness of 6 ° fH. Then they were washed for 15 minutes at 25 ° C in a tergotometer filled with 300 ml at 75 rpm. The samples were washed twice for 2 min with water with a hardness of 6 ° fH and dried.

Measured reflectance values, as in Example 2.

Cleaning system dR460 * Cotton Polycotton Polyester Composition 1 20.96 19.89 26.95 Comparative Composition B 16.3 16.26 13.17

It is shown that the effectiveness of microemulsions is higher than that of commercially available liquid detergent.

Example 4. The inclusion of a flavoring substance

In this example, flavoring agents were included in the microemulsion (Composition 2) and a comparison was made with the composition of a liquid detergent other than a microemulsion (Comparative Composition C).

Ingredient Composition 2 (%) Composition C (%) Na-LAS 9.9 9.9 SLES 8.5 8.5 C8-EO3 ^*) eleven eleven C12-EO7 ^*) 27 27 C12 fatty acid methyl ester 19 Water 19 38 NaCl 2.65 2.65 Flavoring agent 1.4 1.4 Fluorescent substance and enzyme 1.24 1.24 Composition Colorless, transparent microemulsion Liquid crystal, opaque Viscosity (MPa · s) one hundred > 10,000 *) Nonionic surfactant represented by ethoxylated alcohol.

The above table represents a microemulsion in comparison with a similar composition without oil / solvent, which is not a microemulsion.

Flavors deposited on tissue were quantified by the SPM-GC method (solid phase microextraction - gas chromatography).

Chromatographic measurements (peak area) Composition 2 (× 10 ⁶ ) Composition C (× 10 ⁶ ) After washing (wet) fourteen 1,5 1 day (dry condition) 1.35 0.9 3 days after drying 0.7 0.5

The above table shows that the aromatic effect of the microemulsion is higher than in the case of a conventional detergent (not a microemulsion).

Example 5. Mosquito properties

In this example, a mosquito repellent (lemon verbena oil) was included in the microemulsion (Composition 3) and a comparison was made with a similar composition of a mosquito repellent-free liquid detergent other than microemulsion (Comparative D).

Ingredient Composition 4 (%) Composition 5 (%) Composition 6 (%) Composition 7 (%) Na-LAS 7.7 7.7 7.7 7.7 SLES 6.2 6.2 6.2 6.2 C8-EO3 * 9.2 9.2 9.2 9.2 C12-EO7 * 25.7 25.7 25.7 25.7 C12 fatty acid methyl ester 24.4 18.3 6.1 Verbena lemon 6.1 18.3 24.4 Water 24.4 24.4 24.4 24.4 NaCl 2,4 2,4 2,4 2,4 Composition Colorless, transparent microemulsion Colorless, transparent microemulsion Colorless, transparent microemulsion Colorless, transparent microemulsion Viscosity (MPa · s) one hundred one hundred one hundred one hundred *) Nonionic surfactant represented by ethoxylated alcohol.

The above table represents a microemulsion in comparison with a similar composition without oil / solvent, which is not a microemulsion.

The ability to deter mosquitoes was tested in a group of 4 volunteers.

Each member of the expert commission in the territory inhabited by a large number of mosquitoes wore a shirt washed with 2 g / l (for the washing method, see above) of any of these compositions. The experiment was repeated twice (4 times in 2 = 8 trials). The table below shows the averaged values.

Ingredient Composition 4 (%) Composition 5 (%) Composition 6 (%) Composition 7 (%) Lack of approaching mosquitoes 0 0 one 2 Few mosquitoes 0 2 one 0 Many mosquitoes 2 0 0 0

The table above shows that when applying a mosquito repellent using microemulsion, mosquito repellent properties were achieved.

Claims (12)

1. The composition of a bi-continuous washing microemulsion containing:
a) 40-90 wt.% surface-active system containing:
i) 10-50 wt.% a surface-active system of a linear or branched fatty alcohol having 5-8 carbon atoms, or a condensation product of a linear or branched fatty alcohol having 5-8 carbon atoms and containing no more than 5 alkylene oxide groups, and mixtures thereof; and
ii) an additional surfactant; and
b) 5-30 wt.% an aqueous solution containing:
i) water; and
ii) an electrolyte, in addition to the surface active system (a),
characterized in that the aqueous solution has an ionic strength of 0.1-4 mol / l; and
c) 5-30 wt.% oil or solvent, characterized by the presence of:
i) Hansen solubility index between 14 and 20 (MPa) ^0.5 ; and
ii) the solubility of solid trilaurin fatty material in oil in excess of 3 wt.%;
and, in addition, characterized in that the viscosity of this composition is less than 1000 MPa · s (25 ° C and 20 s ^-1 ). 2. The composition according to claim 1, in which the alkylene oxide is ethylene oxide. 3. The composition according to claim 1, in which the Hansen solubility index is between 16 and 18 MPa ^0.5 . 4. The composition according to one of claims 1 to 3, in which the oil is selected from essential oils, oils based on fatty acids, mono- and triglycerides, polyester derivatives of sugars and sucrose polyesters, as well as terpenes and mixtures thereof. 5. The composition according to one of claims 1 to 3, in which the solvent is selected from fatty acid alkyl esters and / or fatty alcohols, preferably obtained from renewable sources, such as palm, coconut, soy, with a distribution of chain lengths of fatty acids from C7 to C22 and the distribution of chain lengths of the alkyl ester group 1-22, as well as mixtures thereof. 6. The composition according to claim 1, in which the pH of the composition is between 5 and 9. 7. The composition according to claim 1, additionally containing a mosquito component. 8. The composition according to claim 7, in which the mosquito component is selected from lemon verbena oil, citronella oil and lemon sorghum oil, as well as mixtures thereof. 9. The composition according to claim 1, additionally containing a flavoring substance. 10. A sprayer containing the composition according to one of claims 1 to 9. 11. A device for preliminary removal of stains, selected from a pen to remove stains, ball stain remover, pens with a brush containing the composition according to one of claims 1 to 9. 12. A method of preparing a microemulsion according to one of claims 1 to 9, comprising the following sequence of steps:
a) adding a surfactant system to the oil / solvent,
b) mixing them together using an overhead mixer,
c) optionally adding hydrophobic ingredients,
d) adding an aqueous phase containing electrolytes.