LU92931B1 - COMPOSITION AND METHOD OF PEST CONTROL - Google Patents

Abstract

The present invention relates to a room temperature liquid suppressor composition comprising: • A C8 to C32 linear or branched chain fatty alcohol having a melting point greater than 35 ° C • A liquid solvent at room temperature and having a vapor pressure between 1kPa and 50kPa at 25 ° C. The invention also relates to a method for treating parasites comprising contacting the parasite with such a composition. The composition and method particularly target lice, ticks, bed bugs and mites. 92931

Description

Composition and method antiparasites

Introduction [0001] The present invention relates to a composition and an antiparasitic method for combating numerous arthropods including ectoparasites such as lice / nits, ticks, bed bugs, mites, etc.

More particularly, the present invention relates to the general technical field of antiparasitic products for topical use, used in particular on the skin and / or the scalp, and may be for example in fluid, liquid or semi-liquid form. The present invention does not involve any natural or chemical insecticide in its composition.

There are several types of treatments against ectoparasites and especially against lice, which have evolved over the years.

[0004] The first generations of treatments consisted of neurotoxic insecticides such as malathions, pyrethrins and pyrethroids, lindane and so on. These insecticides destroy the nervous system of ectoparasites including lice. Neurotoxic drugs do not work on nits because they do not have a nervous system for the first three days.

These neurotoxic insecticide treatments can cause various disorders in treated patients and ectoparasites can develop resistance to these products, making the treatment thus ineffective. In addition, these products are particularly irritating and aggressive for the scalp. They are also non-biodegradable.

This kind of treatment is hardly used nowadays.

Current generations of anti-lice compositions consist of vegetable oils and mineral oils, which act in particular by penetrating the respiratory orifices of lice and nits.

Oily anti-lice compositions are difficult to rinse and only remove hair after several consecutive shampoos. Most of these anti-lice compositions must be reapplied at least once, to achieve cure, because they do not have sufficient efficacy on the nits. Treatment with oil-based anti-lice compositions must therefore generally comprise two steps: a first application to eliminate lice; a second application after 7 to 10 days to eliminate the naked eggs after the first application.

Furthermore, all treatments must be accompanied by a more or less rigorous combing, wick per wick, or at least, respecting a protocol mentioned by the manufacturer because they are not sufficiently effective on the nits. The combing time can be very long, for long hair or impossible for frizzy hair.

The vegetable oils used in these treatments may be essential oils. The effectiveness of vegetable oils depends on the levels of plant active ingredients, the nature of the extracts and the potentiation with other ingredients.

The effectiveness of mineral oils, based on silicones, is linked to a long presence on the scalp, due to the low rinsability of the product. If these approaches are satisfactory in terms of efficiency on lice, the interest on the nits is lower because these fat, too thick and too viscous, do not have the ability to penetrate the respiratory holes of nits of smaller size about 4pm at the entrance of each micropyle and about 1pm at the entrance of the operculum (against about 20 to 30pm for the lice) but especially more complex and better protected forms including a filter matrix behind the operculum. In fact, all these products having a less effective on the slow ones, must necessarily be reapplied 7 to 10 days later, necessary period to the hatching of the nits and the appearance of the young lice, them only sensitive to these substances. During this time of long but necessary waiting between two applications, the subject remains infested and contagious for the entourage or the infantile communities. Finally, the mode of action in two applications, and the unpleasant cosmetic aspect of these fats exposes them to a rejection on the part of the patients and to a risk of less observance.

OBJECT OF THE INVENTION [0012] The object of the present invention is to provide a liquid at room temperature antiparasitic composition without neurotoxic insecticides.

General description of the invention [0013] In accordance with the invention, this objective is achieved by a liquid phase antiparasitic composition comprising:

A linear or branched chain C8 to C32 fatty alcohol with a melting point above 35 ° C

A solvent that is liquid at ambient temperature and has a vapor pressure of between 1 kPa and 50 kPa at 25 ° C.

These compositions contain no neurotoxic insecticide. The effectiveness of the composition is based in particular on the crystallization / solidification of an ingredient inside the parasite. Indeed, thanks to the solvent, the active ingredient that is to say the fatty alcohol is solubilized and can penetrate inside the parasite. The solidification of the active ingredient takes place inside the parasite after evaporation of a part of the solvent contained in the composition. The active principle thus causes a rupture of the internal structures leading to the death of the parasite.

The presence of a solvent also facilitates the penetration of the product into the parasite including the louse and the slow, because of the low surface tension and the hydrophilic balance / lipophilic (balance HLB) of the composition.

The present invention relates to compositions for the control of ectoparasites and more particularly to the treatment of human or animal pediculosis, including pediculosis induced by lice and / or slow, present in the hair of the human.

An advantage of the present composition is that it does not require shampoo or combing to combat pediculosis while being effective in one application on both parasites and eggs.

According to a preferred embodiment, the linear or branched chain C 8 to C 32 fatty alcohol has a melting point of less than 85 ° C., preferably less than 70 ° C. and particularly preferably less than 65 ° C. .

According to a preferred embodiment, the antiparasite composition comprises a mixture of two or more linear or branched chain C8 to C32 fatty alcohols having a melting point of between 35 ° C and 85 ° C.

Preferably, the antiparasitic composition comprises between 1% and 12% by weight of a fatty alcohol respectively of a mixture of two or more fatty alcohols.

The liquid solvent at room temperature has a vapor pressure preferably between 2kPa and 40kPa at 25 ° C.

The liquid solvent at room temperature may comprise water, a surfactant, propylene glycol, an ether such as ether dicaprylyl ether (dioctyl ether), isopropanol, cyclopentasiloxane, diethylhexylcarbonate, decyloleate (ester), PPG3-benzylethermyristate (ester) and / or sorbitan monolaurate (ester) and a mixture of one or more of these products. The following solvent mixtures are particularly preferred water and a surfactant, isopropanol and cyclopentasiloxane dicaprylyl ether, diethylhexylcarbonate and decyloleate PPG3 benzyl ether myristate (ester) and sorbitan monolaurate (ester) The surfactants may be preferably cationic, but it can also be anionic, nonionic and amphoteric surfactants.

The linear or branched fatty alcohol is preferably chosen from: myristyl alcohol, cetostearyl alcohol (mixture of cetyl alcohol and stearyl alcohol) or a mixture thereof.

According to another aspect, the invention also relates to a parasite treatment method comprising bringing the parasite into contact with a liquid phase antiparasitic composition comprising:

A linear or branched chain C8 to C32 fatty alcohol with a melting point above 35 ° C

A solvent that is liquid at room temperature and has a vapor pressure of between 1 kPa and 50 kPa at 25 ° C., allowing it to act for a period of between 1 minute and 1 hour before rinsing it.

The parasites that can be effectively treated by these compositions and by the method are arthropods, preferably selected from lice, ticks, bed bugs and mites.

DETAILED DESCRIPTION WITH EXAMPLE [0028] Other features and characteristics of the invention will become apparent from the detailed description of some advantageous embodiments by way of illustration, with reference to the examples mentioned below.

The composition for the treatment of pediculosis is in a first liquid physical state for easy application to a parasite. At least one of the components of the composition then enters the interior of the parasite and solidifies and causes the death of the parasite.

The composition advantageously has a viscosity allowing it to be spread easily on the scalp and hair.

The composition is applied to the entire scalp, all hair so as to completely cover all parasites and all eggs that may be present. As the composition has a strong capillarity and a very low surface tension, it easily penetrates the interior of the parasites and their eggs, in particular through their passive respiratory system.

Subsequently will be described by way of example an anti-lice lotion for human hair. However, it is perfectly conceivable that the composition is included in a formulation of shampoo, gel, spray or any other hair product.

Five properties make the feature of the present antiparasitic composition: 1) The composition prevents the solidification of the active ingredient at the time of manufacture of the industrial mixture and in its final packaging. This is achieved by solubilizing the ingredient in a solvent especially in "oily esters" such as dicaprylyl ether (dioctyl ether), decyl oleate and silicone: cyclopentasiloxane, an alcohol and / or a mixture of water and surfactants. 2) The composition makes it possible to introduce into the parasite an active which solidifies there. The carrier ingredients - the solvents - of the active ingredient were selected for their lice penetration properties (viscosity, polarity) and their penetration properties of the super-hydrophobic (non-wetting) structures of the interior of the nits (surface tension and capillary adhesion, law of Jurin, pressure of Laplace ...). 3) The composition makes it possible to lower the melting point of the active ingredient. Depending on the properties of the solvent types and the active ingredients to be solubilized, the melting points will be different. In the present composition, the possible combinations between the types of solvents and the active ingredients are specifically selected to be adapted to the peculiarities of a scalp of a human body (physicochemical properties, especially temperature, including the different zones). scalp, which varies between 26 ° C and 33 ° C) or an animal body. 4) Among the solvents, the most volatile substances will be preferentially selected (water and alcohol / volatile fat (such as silicone especially cyclopentasiloxane) for their fast evaporation properties, leading to the precipitation of the active ingredient. The active ingredient is one of which one of the characteristics is the transition from the liquid state to the solid state, depending on its melting point and its concentration in a solvent (solubility coefficient).

In the context of the present invention, there is developed a composition which comprises a first liquid state, very capillary, dispersible / dispersible, which penetrates the louse and the slow and a solid state, which will have the destructive mechanical effect of the insect. Indeed, the composition comprises a solvent which, by evaporating at the temperature of the scalp and strands of hair solidifies / crystallize an active ingredient in the parasite, causing the rupture of the organs.

The mechanism of penetration of the composition is based on the characteristics of the respiratory system of insects, including Pediculus huma-naked. These insects have a passive mode of respiration. In the louse, the abdominal spiracles are permanently open atriums, without closing mechanisms. They are therefore likely to be penetrated by a very capillary solution. The atrium lined with wax has a hydro-phobic / lipophilic structure. Since the composition comprises a lipophilic substance - the fatty acid having a carbon chain greater than C8 - it penetrates easily inside the louse. In the slow, the micropyls are very small orifices which allow the exchanges necessary for the aerobic development of the larva. In addition, very fine invaginations do not allow a liquid with a too high surface tension to penetrate inside.

As a result, the mechanism of action of the composition is based on the presence of a surfactant fluid to reduce the surface tension and promote migration by capillarity of the mixture.

The cationic surfactant promotes the attachment of the solution on the anionic hair. It promotes in turn the penetration between the scales of the hair, and migration, slips under the sleeve that keeps the slow hooked to the hair. By evaporating, the removal of the water causes part of the crystallization of the active ingredient which generates a rupture of the natural cement which maintains the slow (spumaline) and decreases the adhesion of said spumaline to the hair.

The treatment method comprises a composition application step, on the scalp and / or hair of the user. During this application step, the user pours the composition directly onto the hair and the scalp. The user can then facilitate the distribution of the composition, massaging to distribute in all the locks to the root, so that the product penetrates the hair by capillarity.

After this application step, the treatment method comprises a resting step of between one (1) minute and one (1) hour, during which the composition must be left on the scalp, so as to what said composition can act. The treatment method preferably further comprises, after the resting step, a rinsing step during which the present composition is removed, at least in part, on the scalp and / or the hair of the user. In practice, the user rinses the hair and the scalp. He can if he wishes to have a shampoo to complete the washing.

EXAMPLES

Several examples of pediculicidal compositions are presented, for purely illustrative and non-limiting purposes, in the following description: EXAMPLE 1

EXAMPLE 2

EXAMPLE 3

EXAMPLE 4

EXAMPLE 5

EXAMPLE 6

Efficacy Test Protocol [0041] All ingredient combinations were tested on lice and nits. The effect on lice was characterized after different contact times: at 1 hour, 15 minutes, 5 minutes and 3 minutes. Only formulas effective at 100% at 1 hour were tested at 15, 5 and 3 minutes. Regarding the louse, we check if the animal moves and wakes up after 3 hours to appreciate

the pediculicidal effect. The lenticidal effect was observed after 5-7 days (outbreak record).

The tests were performed on lice at different stages of development. Outbreak rates were compared to control groups. The natural hatching rate of nits is 80%. In comparison, how many outbreaks occurred on the nits placed in contact with the products tested? After the contact time with the product, two rinsing modalities were applied. On the one hand, a rinse with water. On the other hand, a wash with shampoo.

Efficiency test:

Several proportions were tested in the ranges provided, for each formula. Results

Effectiveness expressed as% of lice eliminated - in% of nits eliminated

Claims (15)

1. Anti-parasitic liquid composition at room temperature comprising: • A linear or branched C 8 -C 32 fatty alcohol with a melting point greater than 35 ° C. • A solvent that is liquid at ambient temperature and has a vapor pressure of between 1 kPa and 50kPa at 25 ° C. 2. anti-parasitic composition according to claim 1, characterized in that it comprises a mixture of two or more C8 to C32 linear or branched chain fatty alcohols having a melting point between 35 ° C and 85 ° C. 3. Anti-parasitic composition according to claim 1 or 2, characterized in that it comprises between 1% and 12% by weight of a fatty alcohol respectively of a mixture of two or more fatty alcohols. 4. antiparasitic composition according to claim 1, characterized in that the solvent comprises water and a surfactant. 5. anti-parasitic composition according to claim 1, characterized in that the solvent comprises propylene glycol. 6. antiparasitic composition according to claim 1, characterized in that the solvent comprises an ether. 7. antiparasitic composition according to claim 6, characterized in that the ether is dicaprylyl ether (dioctyl ether). 8. antiparasitic composition according to claim 1, characterized in that the solvent comprises isopropanol and cyclopentasiloxane. 9. anti-parasitic composition according to claim 8, characterized in that the solvent comprises a mixture of 10 to 20% by weight of isopropanol and 70-80% by weight of cyclopentasiloxane. 10. Antiparasite composition according to claim 1, characterized in that the solvent comprises a mixture of dicaprylyl ether 40-50% (volatile oil ester), diethyl hexyl carbonate 10-30% (ester) and decyl oleate 15-25% 11. anti-parasitic composition according to claim 1, characterized in that the solvent comprises a mixture of PPG3 benzyl ether myristate (ester) and sorbitan monolaurate (ester). 12. Antiparasite composition according to any one of the preceding claims, characterized in that the linear or branched fatty alcohol is selected from: myristyl alcohol and cetostearyl alcohol (mixture of cetyl alcohol and stearyl alcohol) addition parenthesis closure and their mixtures. 13. A method of treating parasites comprising contacting the parasite with a composition according to any one of the preceding claims by letting the composition act for a period of between 1 minute and one hour before rinsing. 14. Parasite treatment process in which the fatty alcohol enters the interior of the parasite, the solvent evaporates and the fatty alcohol solidifies and thus destroys the parasite. The parasite treatment method according to claim 13 or 14, wherein the parasite is an arthropod selected from lice, ticks, bed bugs and mites.