FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. INSECT REPELLENT COMPOSITION COMPRISING ONE OR MORE
INSECT REPELLENT FATTY ACID(S) HAVING BETWEEN 9 AND 21
CARBON ATOMS
2.
1. (A) EVERGREEN LAND LIMITED
(B) China
(C) Unit 3104-05, 31/F Universal Trade Centre 3 Arbuthnot Road,
Central Hong Kong, China
The following specification particularly describes the invention and the manner in
which it is to be performed.
The invention relates to an insect repellent
composition comprising one or more fatty acid(s) having between 9 and 21 carbon atoms.
The invention applies in particular to a composition having a repellent function for harmful insects such as
biting or stinging hematophagous insects, for example mosquitoes.
Such compositions are generally intended to be used either by direct applying them to the skin of a subject,
or indirectly in the air or on other surfaces, for example by means of a sprayer, a ball applicator or other
modes of application.
For example, US-5 594 029 describes a composition
intended for topical application to the skin of a human or animal subject or to clothing, said composition comprising coconut fatty acids used for their insect repellent properties.
Similarly, WO-00/72676 discloses a composition,
especially intended for application to the skin and/or clothing of a subject, in which lauric (or dodecanoic)
acid is used as a repellent against ticks.
These compositions generally comprise a solvent
consisting mainly of water, such solvents being easy to obtain but requiring the addition of surfactants to be really effective as a solvent for insect repellent
components.
In addition, these solutions are not entirely
satisfactory, in that they do not have a sufficient effectiveness over time. As a result, they require regular reapplication, which can be tedious and lead to
interruptions in protection.
The invention aims to improve the prior art by
proposing in particular an insect repellent composition having improved effectiveness over time while being easy to apply to the skin of a subject. For this purpose, the invention provides an insect
repellent composition comprising:
- an insect repellent component comprising one or
more fatty acid(s) having between 9 and 21 carbon atoms;
- a non-aqueous solvent;
10 - less than 1% by weight of water.
Other features and advantages of the invention will
appear in the description which follows of various
particular embodiments, with reference to the appended
figures, in which:
- Figures 1a and 1b are graphs showing the results of a first series of comparative tests carried out in a laboratory on samples of compositions comprising two
different concentrations of a same insect repellent fatty acid according to the invention, said samples further
20 comprising water, especially with an aqueous solvent (“control” samples) or being free of water, especially with a non-aqueous solvent (“test” samples), in order to highlight the effectiveness over time of a water-free
insect repellent composition with a fatty acid and a non aqueous solvent;
- Figure 2 is a graph showing the results of a
second series of comparative tests between water-free samples comprising a same concentration of an insect repellent fatty acid according to the invention and a non-aqueous solvent, some of said samples comprising in
addition an additional insect repellent component, in order to highlight the synergistic effect between the fatty acid and said additional component in a water-free
insect repellent composition with a non-aqueous solvent;
- Figure 3 is a graph showing the results presented
in Figure 2 by supplementing them with results obtained with four other samples in a third series of comparative
tests conducted according to the same protocol as the second series mentioned above.
The invention relates to an insect repellent
composition comprising an insect repellent component comprising one or more fatty acid(s) having between 9 and 21 carbon atoms. In particular, the insect repellent
composition may comprise a single fatty acid or a mixture of fatty acids having between 9 and 21 carbon atoms. Such fatty acids have repellent propertiesespecially against harmful insects such as biting or stinging hematophagous insects, for example mosquitoes.
Fatty acids having a number of carbon atoms greater than 21 are not suitable for topical application to the skin of a subject, in that they give the composition a
pasty constitution making said application difficult. Moreover, such a composition leaves a fatty layer on the skin of the subject that is difficult to remove, which is not desirable.
Similarly, fatty acids having a number of carbon
atoms of less than 9 give the composition an unpleasant odour, which is also not desirable, especially for application to the skin.
The insect repellent fatty acid may comprise a
carboxylic acid, in particular chosen from nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid,
hexadecanoic acid, heptadecanoic acid, octadecanoic acid,
nonadecanoic acid, eicosanoic acid, heneicosanoic acid,
undecylenic acid, citronellic acid, geranic acid or a mixture of at least two of these compounds.
In a particularly effective embodiment, the insect repellent fatty acid has 12 carbon atoms and/or is a saturated or unsaturated fatty acid.
Advantageously, the insect repellent fatty acid
comprises lauric acid (or dodecanoic acid).
The insect repellent fatty acid may also comprise an acid selected from the following group: ω-hydroxy-15-
methyl palmitic, ω-hydroxy phytanic, (2E, 6E, 10E)- geranyl geranic, (2E, 6E, 10E, 14E)-ω-hydroxy geranyl
geranic. The insect repellent fatty acid can also be based on a fatty acid:
- with a methyl branch, in particular chosen from
the following group: (2S)-2-methylheptadecanoic, (E)-11-
methyldodec-2-enoic, 10-methyldodecanoic, 10-
methylundecanoic, 12-methyloctadecanoic, 12-
methylpentadecanoic, 13-methylpentadecanoic, 14-
methylhexadecanoic, 14-methylpentadecanoic, 16-
methylheptadecanoic, 16-methyloctadecanoic, 17-
methyloctadecanoic, 18-methylicosanoic, 18-
methylnonadecanoic, 2-methylbut-2-enoic, 2-
methylhexadecanoic, 20-methyldocosanoic, 20-
methylhénicosanoic; and/or
- with a propyl branch, in particular chosen from
the following group: 2-n-propyl-2-pentenoic, 2-n-propyl-
3-pentenoic, 2-n-propyl-4-pentenoic, 2-propyl-2,4- pentadienoic, 2-propyl-2-pentenoic.
The insect repellent fatty acid may also be derived
from at least one hydrolysed vegetable oil, chosen in particular from copra (coconut) oil, palm oil, argan oil,
almond oil, castor oil, avocado oil, wheat germ oil or a mixture of at least two of these oils.
In particular, the composition comprises between 5%and 50%, especially between 12.5% and 37.5%, by weight of
the insect repellent fatty acid.
The composition further comprises a non-aqueous
solvent, which allows to improve its effectiveness over time. In particular, the composition comprises less than 1%
by weight of water, this amount corresponding to any potential residual water doses present in the various components forming said composition.
However, the composition is preferably free of water, to further improve its effectiveness over time. The non-aqueous solvent may comprise at least one component chosen from alcohols, acids, alkanes, alkenes,
aldehydes, amines, amides, ketones, esters, ethers, lactones, silicones, siloxanes, organosulfites,organophosphorus compounds, mineral oils, vegetable oils,
waxes, terpenes, essential oils, or a mixture of at least two of these components.
The non-aqueous solvent may comprise at least one
alcohol selected from the following group: methanol, ethanol, propanol, butanol, pentanol, hexanol, 1,3- butanediol, monopropanoate, 2-butyloctan-1-ol, 1octanol,
2-butyl-,benzoate, cyclohexanol, (1,7,7-
trimethylbicyclo[2.2.1]hept-2-yl)-(1,7,7-
trimethylbicyclo[2.2.1]hept-2-yl)cyclohexan-1-ol,oxybispropanediol, decanediol, hexanetriol, butanediol, hexanediol, pentanediol, dimethyloctenediol,
butylcyclohexyl butanol, hexenol, methoxybutanol, amyl
acetate, amyl benzoate, benzyl glycol, benzyl alcohol,
1,4:3,6-dianhydro-2,5-di-O-methyl-D-glucitol, 1,1'-
oxidipropan-2-ol, oxydipropan-2-ol,
hydroxypropyloxypropanol, 2-ethylhexane-1,3-diol, 2,6,10-dodecatrien-1-ol, 3,7,11-trimethyl-glycerol, ethane-1,2-
diol, hexan-1-ol, 2-hexyldecan-1-ol, polymer with oxirane
(1:2), hexyldecanol, polymer with oxirane (1:20), 3-
methylbutan-1-ol, 1-isobutoxypropan-2-ol, 3-methylbutan-
1,2-diol, alcohol isopropyl, 1-methoxypropan-2-ol, 3-methoxy-3-methyl-1-butanol, methyl alcohol, 2-methyl-1,3-
propanediol, butan-1-ol, 2,2-dimethyl-1,3-propanediol, 2-
octyldodecan-1-ol, 1,2-dihydroxypentane, 1-phenoxypropan-
2-ol, 3-phenylpropan-1-ol, poly(1,2-butanediol)-6
propylene glycol, propan-1-ol, propylene glycol, 1-butoxypropan-2-ol, 1-propoxypropan-2-ol, 1-(1,1-dimethylethoxy)-2-propanol, 1-methylpropanol, 2-
methylpropan-2-ol, tetrahydrofurfuryl alcohol, 3,4-thiophenediol, 4,4',4''-(1-methylpropanyl-3-
ylidene)tris[6-tert-butyl-m-cresol] 2,2,4-trimethyl-1,3-
pentanediol, 3,5,5-trimethylhexan-1-ol, 2-ethyl-2-hydroxymethyl-1,3-propanediol, 3,5,5-trimethylhexan-1-ol.
The non-aqueous solvent may comprise at least one
acid selected from nonanoic acid and/or D-gluconic acid.
The non-aqueous solvent may comprise at least onealkane or alkene selected from the following group:
pentane, hexane, heptane, octane, nonane, decane,
aromatic hydrocarbons, cycloalkanes, coconut alkanes,
cyclohexane, decafluoropentane, diphenylmethane, 1-dodecene, isoparaffins, heptane, 1-hexadecene,
30 pyrimidinamine, trimethyldodecane, pentadecane, 7-
methylene, 2,2,4-trimethylpentane, 2-methylbutane, 1,3,5-
trimethylbenzene, 2-methylbutene, ligroin, octadecane, 1-8
octadecene, octane, 1-octene, paraffin oil, 1,1,1,3,3-
pentafluoropropane, pentane, 1-bromo-
1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluoroctane,
nonafluoro(trifluoromethyl)cyclopentane,
perfluorododecahydrofluorene, 2-
[difluoro(undecafluorocyclohexyl)methyl]-
1,1,2,3,3,4,4,4a,5,5,6,6,7,7,8,8,8aheptadecafluorodecahydronaphthalene,
petroleum
distillates, propylbenzene, 1-tetradecene, toluene,
10 1,1,1-trichloroethane, 1,2,4-trimethylbenzene,
dimethylbenzene, dodecane, undecane, tridecane, C13-15
alkane.
In particular, the non-aqueous solvent may comprise
an alkane or an alkene chosen from hydrogenated
hydrocarbons, in particular from those presented below
with their CAS (Chemicals Abstracts Service) number and
their full names in parentheses:
- CAS 93685-81-5 (“hydrocarbons, C4, 1,3-butadienefree,
polymd., triisobutylene fraction, hydrogenated”);
- CAS 93685-80-4 (“Hydrocarbons, C4, 1,3-butadienefree,
polymd., tetraisobutylene fraction, hydrogenated”);
- CAS 93685-79-1 (“hydrocarbons, C4, 1,3-butadienefree,
polymd., pentaisobutylene fraction, hydrogenated”).
The non-aqueous solvent may comprise at least one
aldehyde selected from benzaldehyde and/or 2-furaldehyde.
The non-aqueous solvent may comprise at least one
ketone chosen from the following group: acetone,
heptylcyclopentanone, cyclohexanone, 4-hydroxy-4-
methylpentan-2-one, 1-ethylpyrrolidin-2-one, N30
ethylpyrrolidone, undecan-4-olide, 4-hydroxymethyl-1,3-
dioxolan-2-one, butanone, 4-methylpentan-2-one.
The non-aqueous solvent may comprise at least one
amine or amide chosen from the following group: oleamine,
carboxymethyl caprooyl chitosan, N,N-dimethyl decanamide,
1-methylpyrrolidone, N,N'-(poly(oxytetrafluoroethylene,
oxydifluoromethylene)bis(difluoromethylene))bisoctadecana
mide, poly(imino-1,2-ethanediyl), α-hydro-ω-aminoethoxylated
(with an average molar ratio of aziridine of
1000 mol), poly (imino-1,2-ethanediyl), α-hydro-ω-aminoethoxylated,
polyhydroxystearamidopropyl dimethylamine.
The non-aqueous solvent may comprise at least one
ester chosen from the following group: ethyl nonanoate, ethyl lactate, ethyl pyruvate, butylcyclohexyl acetate,
bis(1-methylheptyl)-2-butenedioate, benzoic acid, 2- hydroxy-2-butyloctyl ester, hexanedioic acid, bis(2-
heptylundecyl) ester, benzyl actate, benzyl benzoate, butyl lactate, n-butyl acetate, alkyl benzoate, n-octyl butyrate, butylcyclohexyl acetate, butenedioic acid,
esters (E),bis(C12-15-alkyl), 1,3-diacetate glycerol,
dibutyl adipate, dibutyl oxalate, dibutyl sebacate,butanedioic acid ester, hydroxy-bis(2-butyloctyl),
dioctyl maleate, butanedioic acid ester, bis(2-
ethoxyethyl), aspartic acid, N-acetyl-diethyl ester, diethyl oxalate, diethyl sebacate, diethyl succinate,
dioctyl 2,6-naphthalate, bis(2-ethylhexyl) adipate,bis(2-ethylhexyl) sebacate, bis(2-ethylhexyl) succinate,
dihexyl adipate, adipic acid, dihexyldecyl ester,
decanedioic acid, bis(2-hexyldecyl) ester, diisobutyl
adipate, di-sec-butyl oxalate, bis(2-hexyldecyl)adipate,
diisodecyl adipate, bis-(1-methylheptyl) ester,diisopropyl adipate, diisodecyl adipate, diisopropyl
sebacate, carbonic acid, dimethyl ester, dimethyl maleate,
dimethyl oxalate, dimethyl phthalate, dimethyl succinate, decanedioic acid ester, bis(2-octyldodecyl), dipropyl
adipate, dipropyl oxalate, isooctadecanoic acid,
pentaester with 2,2'-(oxybismethylene)bis[2-
hydroxymethyl-1,3-propanediol], bis(tridecyl) adipate, 3-hydroxy-1,2,4-butanetriyl tri(2-ethylhexanoate), ethyl
acetate, ethyl acetal levulinate, ethyl glycerin acetal
levulinate, propanoic acid, 2-hydroxyethyl ester, ethyl
myristate, [2-(1-ethoxyethoxy)ethyl]benzene, ethyl phenylacetate, 2-ethylhexyl acetate, 2-ethylhexyl benzoate, 1,2,3-propanetriyl tris[acetoxyoctadecanoate],
1,2,3-propanetriyl tris[(R)-12-(acetoxy)oleate], hexyl laurate, 2-hydroxybenzoic acid, 2-hexyldodecyl ester, 2-
methylpentane-2,4-diol, isopentyl acetate, isobutyl acetate, isobutyl benzoate, benzoic acid, 2-hydroxy
isohexadecyl ester, isopropanolamine lanolate, isopropyl acetate, isopropyl myristate (MIL), isopropyl palmitate,
poly(oxy-1,2-ethanediyl)poly(oxy-1,2-propanediyl), α-
isodecyl-ω-carboxymethoxy-1-methylethyl ester,
polyglyceryl-4 esters of linseed oil, 2-methoxy-1-methylethyl acetate, methyl acetate, methyl
laurate/myristate, methyl
oleate/palmitate/linoleate/stearate, polyglyceryl-4
esters of palm kernel oil, polyglyceryl-4
laurate/sebacate, polyglyceryl-6-caprylate/caprate,
polypropanediol, propanediol, propanediol dicaprylate,
propyl acetate, propyl benzoate, propylene carbonate, octadecyl benzoate, 1,1-dimethylethyl acetate, tetradecylpropionates, tetrahydrofurfuryl acetate, tetrahydrofurfuryl acetate, triacetin, tributyl citrate, glycerol tridecanoate, glycerol trioctanoate, propane-
1,2,3-triyl 2-ethylhexanoate, 1,2,3-propanetriyl tris(12- hydroxyoctadecanoate), propane-1,2,3-triyl 3,5,5-11
trimethylhexanoate, triisopropyl citrate, 1,2,3-
propanetriyl triisooctadecanoate, glycerol trilaurate,
propane-1,2,3-triyl tris[(9Z,12Z)-octadeca-9,12-dienoate],
glycerol trimyristate, 1,2,3-propanetriyl trioleate,
glycerol tripalmitate, glycerol tristearate, propane-
1,2,3-triyl triundecanoate, ethylene carbonate, dihydro-
pentyl-2(3H)-furanone, triethyl citrate, tripheptanoin,
heptyl undecelynate, isononyl isononanoate, ethylhexyl
isononanoate, dicaprylyl ether, dicaprylyl carbonate,
tributyl acetyl citrate, dioctyl succinate, dicaprylyl
succinate, diisooctyl succinate, isoamyl laurate, coco
caprylate, coco caprylate caprate.
The non-aqueous solvent may comprise at least one
ether selected from the following group: ethanol,2-(2-
butoxyethoxy)-,1-acetate, 2-(2-butoxyethoxy)ethanol, 2-
butoxyethanol, 2-butoxyethyl acetate, 1,1'-[methylenebis
(oxy)]dibutane, dioctyl ether, diethylene glycol diethyl
ether, di(3-methylbutyl)hydroxybutanedioate, dimethyl
ether, dimethyl glutarate, 1,3-dioxolane, dipropylene
glycol dimethyl ether, dipropylene glycol isobornyl ether,
2-(2-ethoxyethoxy)ethanol, 2-(2-ethoxyethoxy)ethyl
acetate, ethane,1,1'-oxybis, 1-ethoxy-1,1,2,2,3,3,4,4,4-
nonafluorobutane, propane, 2-(ethoxydifluoromethyl)-1,1,
1,2,3,3,3-heptafluoro, 2-ethylhexyl-6-benzyl-2,5-
dioxopiperazin-3-ylacetate, poly(oxy-1,2-ethanediyl),α-
(tetrahydro-2-furanyl)methyl-ω-hydroxy-, isooctyl lactoil
tallate, isooctyl tallate, 1-methoxyhexane,
1,1,1,2,3,3,3,4,4-nonafluoro-4-methoxybutane, 2-
(difluoromethoxymethyl)-1,1,1,2,3,3,3-heptafluoropropane,
1-methylpyrrolidone, dimethoxymethane, cross polymer
polyacrylate-10, tert-butyl methyl ether, 2,2'-
12(ethylenedioxy)diethanol, trimethylpentanol hydroxyethyl
ether, polyglyceryl-10 isostearyl ether.
In particular, the non-aqueous solvent may comprise
at least one ether chosen from polyethylene glycol ethers(PEG) and/or polypropylene glycol ethers (PPG), in particular chosen from the following group: methoxy PEG-
25, methoxy PEG-7, PEG-10, PEG-12, PEG-12 glyceryl linoleate, PEG-16, PEG-14, PEG-18, PEG-135, PEG-150, PEG-, PEG-200, PEG-2 benzyl ether, PEG-200 hydrogenated
10 glyceryl palmate, PEG-220, PEG-3 methyl ether, PEG-32,
PEG-33, PEG-350, PEG-4, PEG-45, PEG-4 methyl ether, PEG-
40, PEG-45, PEG-500, PEG-55, PEG-6, PEG-7, PEG-8, PEG-9,
PEG-80, PEG-90, PEG-6 methyl ether, PEG-7 methyl ether,
hydrogenated PEG-80 glyceryl palmate, PEG/PPG-1/2
15 copolymer, PEG/PPG-10/30 copolymer, PEG/PPG-/65
copolymer, PEG/PPG-10/70 copolymer, PEG/PPG-116/6
copolymer, PEG/PPG-12/35 copolymer, PEG/PPG-125/30
copolymer, PEG/PPG-15/15 acetate, PEG/PPG-150/35
copolymer, PEG/PPG-16/17 copolymer, PEG/PPG-160/30
copolymer, PEG/PPG-160/31 copolymer, PEG/PPG-17/6
copolymer, PEG/PPG-18/4 copolymer, PEG/PPG-19/21
copolymer, PEG/PPG-20/20 copolymer, PEG/PPG-20/60
copolymer, PEG/PPG- 20/65 copolymer, PEG/PPG-20/9
copolymer, PEG/PPG-200/40 copolymer, PEG/PPG-200/70
copolymer, PEG/PPG-22/25 copolymer, PEG/PPG-23/17
copolymer, PEG/PPG-23/50 copolymer, PEG/PPG-240/60
copolymer, PEG/PPG-25/30 copolymer, PEG/PPG-26/31
copolymer, PEG/PPG-28/30 copolymer, PEG/PPG-3/17
copolymer, PEG/PPG-30/35 copolymer, PEG/PPG-30/33
copolymer, PEG/PPG-30/35 copolymer, PEG/PPG-30/55
copolymer, PEG/PPG-35/40 copolymer, PEG/PPG-35/9
copolymer, PEG/PPG-38/8 copolymer, PEG/PPG-4/2 copolymer,
13
PEG/PPG-5/30 copolymer, PEG/PPG-5/35 copolymer, PEG/PPG-
50/40 copolymer, PEG/PPG-6/2 copolymer, PEG/PPG-7/50
copolymer, PEG/PPG-8/17 copolymer, PEG/PPG-8/55 copolymer,
PPG-10 butanediol, PPG-10 caprylyl ether, PPG-10 laurylether, PPG-2 methyl ether, PPG-2 methyl ether acetate,
PPG-2 propyl ether, PPG-2 propyl ether, PPG-3 capryl
ether, PPG-3 methyl ether, PPG-4 methyl ether, PPG-5
capryl ether, PPG-55 glyceryl ether, PPG-6 capryl ether,
SORBETH-20, SORBETH-30, SORBETH-40, SORBETH-6, STEARETH-
12.
The non-aqueous solvent may comprise at least one
lactone selected from D-Glucono-1,5-lactone and/orbutyrolactone.
The non-aqueous solvent may comprise at least one
silicone or siloxane chosen from the following group:
cyclic polymer methylethoxysiloxane,
tetradecamethylcycloheptasiloxane,
dodecamethylcyclohexasiloxane, cyclomethicone,
decamethylcyclopentasiloxane,
octamethylcyclotetrasiloxane, hexamethylcyclotrisiloxane,
propyl trimethicone.
The non-aqueous solvent may comprise at least one
organosulfur, for example dimethyl sulphone, and/or at
least one organophosphorus compound, for example triethyl
phosphate.
The non-aqueous solvent may comprise at least one
mineral and/or vegetable oil and/or wax chosen from the
following group: hydrogenated oil of Atlantic menhaden
(in Latin brevoortia tyrannus), oil of the fruit or podsof the olive tree (in Latin olea europaea), oriental
poppy seed oil (in Latin papaver orientale), commoncastor bean seed oil (in Latin ricinus communis), shark
14liver oil, tall oil, oil chaulmoogra, corn oil, lanolinoil, jojoba oil.
The non-aqueous solvent may comprise at least one
terpene and/or an essential oil selected from thefollowing group: limonene, terpenes and terpenoids, octea
quixos leaf oil, terpineol.
In particular, the non-aqueous solvent may comprise:
- ethanol, especially with a content of between 15%
and 80%, and more particularly between 31.25% and 43.75%,of the total weight of the composition; and/or
- isopropyl myristate (MIP), in particular with a
content of between 10% and 80%, and more particularly
between 31.25% and 43.75%, of the total weight of thecomposition.
The non-aqueous solvent may also comprise:
- isoctyl succinate, especially with a content of
between 50% and 90%, and more particularly between 64.80%
and 79.80%, of the total weight of the composition; and
or
- a mixture of coconut alkanes, coco caprylate and
caprate, in particular with a content of between 10% and
30%, and more particularly of 16.20%, of the total weight
of the composition.
The composition may also comprise an additional
insect repellent component able to act in synergy with
the insect repellent fatty acid, in order to improve all the more its effectiveness over time, and possibly to extend its insect repellent properties to more species of
harmful insects.
In particular, the composition may comprise between 0.1% and 20%, especially between 3% and 4%, by weight of
the additional insect repellent component.
The additional insect repellent component may be
chosen from p-menthane-3,8-diol (PMD) and all the active
agents comprising it, N,N-diethyl-3-methylbenzamide
(DEET), icaridine, butylacetylaminopropionate ethyl
(IR3535), N,N-diethyl phenylacetamide (DEPA), terpenes,
terpenoids, vegetable oils, vinegars, limonoids,
phenylpropanoids, essential oils, pyrethroids, natural
pyrethrins, lactones, piperonyl derivatives, piperines,
benzyl alcohol, malathion, lindane, or a mixture of atleast two of these components.
In particular, p-menthane-3,8-diol (PMD) is a plantderived
ingredient that is particularly effective in
repelling biting or stinging hematophagous insects such as mosquitoes.
The additional insect repellent component may
include in particular at least one essential oil,
especially selected from the essential oils of Java citronella, geranium, palmarosa, lavandin, lavender, mint,
clove, anise, and cinnamon.
In particular, the additional insect repellent
component may comprise essential oil derived from lemon
eucalyptus or citronella, such as for example the
essential oils marketed under the trade names Citrepel® and Citriodiol®, such oils being known natural sources of p-menthane-3,8-diol.
The additional insect repellent component may also comprise at least one component selected from the following groups:
- terpenes or terpenoids, for example of the
citronellal, geraniol, linalool, menthol, nerolidol, terpin-4-ol, gedunine, quassine or nootkatone type; 16
- vegetable oils, for example neem oil or andiroba
oil;
- vinegars, for example quassia vinegar;
- limonoids: for example azadirachtin or andirobine;
- phenylpropanoids, for example eugenol or
cinnamaldehyde;
- lactones, for example of the nepetolactone, δ-
decalactone or δ-undecalactone type;
- piperonyl derivatives, for example of the
piperonyl acetate, piperonyl acetone, piperonyl aldehyde,
piperonyl alcohol (sesamol), dillapiol or piperlongumine
type;
- piperines, for example of the simple piperine,
tetrahydropiperine, bietamiverine, butopiprine and/or the salts thereof, or piperazine type;
- other types of components such as, for example,
undecanone, 6-methyl-5-hepten-2-one, dimethicone or 1,2-
octenediol.
The composition may further comprise a stabilising component comprising an unsaturated fatty acid, in
particular based on oleic acid.
Examples During laboratory testing procedures, several samples of insect repellent compositions were prepared in order to test their effectiveness over time.
To do this, prior to the evaluation of the samples, approximately 50 adult female specimens of several mosquito species, including the tiger mosquito (in Latin Aedes albopictus), were enclosed in a 50 x 50 x(cm)
plexiglass cage, then the aggressiveness of these
17 specimens was tested by introducing into the cage for thirty seconds a “control” forearm not coated with an insect repellent composition. At the end of this test, at
least ten attempts of landings on and/or stings to the forearm were observed.
Then, the samples were tested in turn according to a same experimental protocol, the steps of which are explained below. In particular, the protocol used is in
line with WHO's “Topical Guidelines (WHOPES 2009)”entitled “Guidelines for efficacy testing of mosquito
repellents for human skin - WHO/HTM/NTD/WHOPES/2009.4”.
First, a dose of a test sample was applied to a
“test” forearm, in particular at a density of about
1g/600 cm2. Then, the “test” forearm was introduced into the
cage containing the mosquitoes for nine test periods P0,
P1, P2, P3, P4, P5, P6, P7, P8 of three minutes each repeated after an interval of one hour (the initial period P0 corresponding to the instant of application itself and the final period P8 corresponding to the eighth hour after said application), without reapplying
the sample. During each P0-P8 test period, the
effectiveness of the sample was evaluated by calculating a percentage of inhibition PI of the number of landings
25 and/or bites between the “test” forearm and the “control”
forearm.
Example 1
During a first series of tests, four samples of
insect repellent compositions were prepared, among which:
18
- two “control” samples WW1, WW3 (aqueous solvent)
each comprising 87.25% by weight of water and 0.25% by
weight of a sodium lauryl sulfate (SLS) surfactant, and:
-- for the WW1 sample: 12.5% by weight of lauric
acid;
-- for the WW3 sample: 37.5% by weight of lauric
acid;
- two “test” samples WL1, WL3 (non-aqueous solvent)
comprising:
-- for sample WL1: 43.75% by weight of ethanol,
43.75% by weight of isopropyl myristate (MIL) and 12.5%
by weight of lauric acid;
-- for sample WL3: 31.25% by weight of ethanol,
31.25% by weight of isopropyl myristate (MIL) and 37.5%
by weight of lauric acid.
In particular, the “test” samples comprised about 0% by weight of water, so that each formed a water-free composition.
Each of these four samples WW1, WW3, WL1, WL3 were tested according to the experimental protocol explained
above, and the PI percentages obtained at each period P0-
P8 are listed in the graphs of Figure 1a (for samples WW1 and WL1) and Figure 1b (for samples WW3 and WL3).
For WW1, WW3 "control" samples, the baseline
effectiveness was relatively low, with a PI percentage of
61.45% for the WW1 sample and a PI percentage of 21.70%
for the WW3 sample, during the initial period P0. In
addition, this effectiveness has rapidly decreased over
time, since the PI percentage has dropped to 0% from the third period P2 for the WW1 sample, or even from the
second period P1 for the WW3 sample containing a higher concentration of lauric acid.
On the other hand, for the WL1, WL3 "test" samples,
the effectiveness remained very high during the nine periods P0-P8, with PI percentages greater than 90%, or
even greater than 95% for the WL1 sample with 12.5% of
5 lauric acid. In particular, at the end of the last test
period P8, the samples WL1, WL3 had PI percentages of
respectively 96.87% and 93.56%.
Thus, the results obtained during this first series of tests have highlighted a significant increase in the effectiveness over time of an insect repellent
composition combining lauric acid with a non-aqueous solvent, and in particular water-free, with respect to a
composition using lauric acid with an aqueous solvent. Example 2
In a second series of tests, seven samples of insect repellent compositions were prepared, each sample being
free of water and comprising:
- an insect repellent component comprising lauric
acid and/or another type of insect repellent component;
- a non-aqueous solvent comprising:
-- ethanol (between 41.75% and 48% of the total
weight of the composition); and
25 -- isopropyl myristate (MIL) (between 41.75% and 48%
of the total weight of the composition).
Among these samples, four "control" samples WL1, W4,
W11, W8 were provided, each of which included a single
type of insect repellent component. Therefore:
- the sample WL1, similar to that prepared during
the first test series, included lauric acid (12.5% by
weight);
- the sample W4 included p-menthane-3,8-diol (PMD)
(3% by weight);
- the sample W11 included N, N-diethyl-3-
methylbenzamide (DEET) (3% by weight);
- the sample W8 included lavandin essential oil (4%
by weight).
In addition, three "test" samples WL4, WL11, WL8
were provided, each of which included lauric acid in the same proportions as the sample WL1 (12.5% by weight), mixed with respectively one of the three other types of
insect repellent components present in the samples W4,
W11, W8, with the same proportions as the corresponding
sample W4, W11, W8. Therefore:
- the sample WL4 comprised 3% by weight of PMD;
- the sample WL11 comprised 3% by weight of DEET;
- the sample WL8 comprised 4% by weight of lavandin
essential oil.
Each of these seven samples were tested according to the experimental protocol explained above, and their complete protection time (CPT), corresponding to the
number of hours during which the above-mentioned PI percentage is greater or equal to 99%, have been listed in the graph of Figure 2.
For the "control" samples WL1, W4, W11, W8, the
complete protection time was low (about 3 hours for the "PMD" alone sample W4 and 4 hours for the "DEET" alone
sample W11), or even zero (for the "lauric acid alone" sample WL1, the PI percentage was only 97.9% during the initial period P0).
On the other hand, for the "test" samples WL4, WL11, WL8, the complete protection time proved to be greater.
Indeed, this time has even come to 8 hours for the 21 samples WL4, WL8 mixing lauric acid with PMD and lavandin essential oil respectively, which represents a very
significant increase in efficiency compared to the corresponding "control" samples WL1, WL4, WL8, which contained only one of these insect repellent components.
Example 3
In a third series of tests, four samples of insect repellent compositions were prepared, each sample being
free of water and comprising:
- an insect repellent component comprising lauric
acid and/or another type of insect repellent component;
- a non-aqueous solvent comprising:
-- isoctylsuccinate (between 64.80% and 79.80% of
the total weight of the composition); and
-- a mixture of coconut alkanes, coconut caprylate and caprate (16.20% of the total weight of the
composition).
Among these samples, two "control" samples ASPF07, W12 were provided, each of which included a single type
of insect repellent component. Therefore:
- the sample ASPF07 included ethyl
butylacetylaminopropionate (IR3535) (4% by weight);- the sample W12 included icaridine (4% by weight).
Furthermore, two "test" samples ASPF08, WL12 were
provided, each of which included lauric acid in the same
proportions as the sample WL1 (12.5% by weight), mixed with respectively one of the other two types of insect
repellent components present in samples ASPF07, W12, with
the same proportions as the corresponding sample ASPF07,
W12. Therefore:
22
- the sample ASPF08 comprised 4% by weight of IR3535;
- the sample WL12 comprised 4% by weight of
icaridine.
Each of these four samples were tested according to the experimental protocol explained above, and their
complete protection time (CPT), corresponding to the number of hours during which the above-mentioned PI percentage is greater or equal to 99%, have been listed
in the graph of Figure 3, which also includes the results obtained during the second test series and presented in
Figure 2.
For these four samples, results similar to those
observed during the second series of tests were obtained,
namely:
- a low complete protection time for the "control"
samples ASPF07, W12, the complete protection time was low
(about 3 hours for the "IR3535" alone sample ASPF07 and 4
hours for the "icaridine" alone sample WL11);
- a longer complete protection time for "test"
samples ASPF08, WL12, i.e. 5 hours for the sample ASPF08
mixing lauric acid with IR3535, or even 7 hours for the
sample WL12 mixing lauric acid with icaridine.
Thus, the results obtained during these second and third series of tests made it possible to highlight the
synergistic effect between the insect repellent
properties of a fatty acid according to the invention
with an additional component in a composition comprising
a non-aqueous solvent, and especially water-free, said effect resulting in a significant increase in the
effectiveness over time of an insect repellent
composition compared to a composition comprising only a fatty acid or another type of insect repellent component.

WE CLAIM:
1. An insect repellent composition comprising:
- an insect repellent component comprising one or
more fatty acid(s) having between 9 and 21 carbon atoms;
- a non-aqueous solvent;
- less than 1% by weight of water.
2. An insect repellent composition according to claim 1,
characterised in that the insect repellent fatty acid has
12 carbon atoms.
3. An insect repellent composition according to one of
claims 1 or 2, characterised in that the insect repellent
fatty acid comprises a carboxylic acid, in particular lauric acid.
4. An insect repellent composition according to any one
of claims 1 to 3, characterised in that the insect
repellent fatty acid comprises a saturated or unsaturated fatty acid.
5. An insect repellent composition according to any one of claims 1 to 4, characterised in that it is free of
water.
6. An insect repellent composition according to one of claims 1 to 5, characterised in that the insect repellent
fatty acid is derived from at least one hydrolysed vegetable oil, in particular selected from copra oil, palm oil, argan oil, almond oil, castor oil, avocado oil,
wheat germ oil or a mixture of at least two of these oils.
7. An insect repellent composition according to any one of claims 1 to 6, characterised in that it comprises
between 5% and 50%, especially between 12.5% and 37.5%, by weight of the insect repellent fatty acid.
8. An insect repellent composition according to any one of claims 1 to 7, characterised in that the non-aqueous solvent comprises at least one component selected from alcohols, acids, alkanes, alkenes, aldehydes, amines,
amides, ketones, esters, ethers, lactones, silicones, siloxanes, organosulfides, organophosphorus compounds, mineral oils, vegetable oils, waxes, terpenes, essential
oils, or a mixture of at least two of these components.
9. An insect repellent composition according to claim 8,
characterised in that the non-aqueous solvent comprises ethanol, in particular with a content of between 15% and
80%, and more particularly between 31.25% and 43.75%, of
the total weight of said composition.
10. An insect repellent composition according to one of claims 8 or 9, characterised in that the non-aqueous solvent comprises isopropyl myristate, in particular with a content of between 10% and 80%, and more particularly
between 31.25% and 43.75%, of the total weight of said composition.
11. An insect repellent composition according to any one of claims 8 to 10, characterised in that the non-aqueous solvent comprises isoctylsuccinate, in particular with a
content of between 50% and 90%, and more particularly between 64.80% and 79.80%, of the total weight of the composition.
12. An insect repellent composition according to any one of claims 8 to 11, characterised in that the non-aqueous solvent comprises a mixture of coconut alkanes, coco caprylate and caprate, especially with a content of between 10% and 30%, and more particularly of 16.20%, of
the total weight of the composition.
13. An insect repellent composition according to any one of claims 1 to 12, characterised in that it comprises an additional insect repellent component able to act in
synergy with the insect repellent fatty acid.
14. An insect repellent composition according to claim 13, characterised in that it comprises between 0.1% and 20%, especially between 3% and 4%, by weight of the
additional insect repellent component.
15. An insect repellent composition according to one of claims 13 or 14, characterised in that the additional insect repellent component is selected from among pmenthane-
3,8-diol, N,N-diethyl-3-methylbenzamide,
icaridine , ethyl butylacetylaminopropionate, N,N-diethyl phenylacetamide, terpenes, terpenoids, vegetable oils, vinegars, limonoids, phenylpropanoids, essential oils,
especially of lavandin, pyrethroids, natural pyrethrins, lactones, piperonyl derivatives, piperines, benzyl