ORGANIC-SULPHIDE COMPOSITION WITH MASKED ODOUR
[0001] The present invention relates to tlie field of organic sulphides and more
particularly that of alkyl sulphides or dialkyi sulphides, especially dimethyl sulphide
(or dimethyl disulphide, or alternatively DMDS), and also that of the oxides thereof,
and especially of dimethyl sulphoxide (or DMSO).
[0002] It is well known that organic sulphides have, in general, a strong,
unpleasant, or even aggressive odour. In particular, DMDS has a strong and
aggressive odour due in part to the presence of highly odorous impurities and in
part to the garlicky and ethereal odour intrinsic to DMDS. The same is true of most
organic sulphides. In general, the oxides of these organic sulphides, in particular
DMSO, have a less aggressive odour, but, depending on the concentrations of
impurities, this odour can, however, be unpleasant, and an impairment for the end
user.
[0003] This strong odour hinders the increased growth of these products, for
example in the case of DMDS, in applications such as the sulphurization of
catalysts or as loading additive for steam cracking. However, in comparison with
other products used in these applications, such as tert-alkyi polysulphides, DMDS
exhibits numerous advantages, in particular a high sulphur content (68%) and noncoking
degradation products (CH4, H2S). Furthermore, in these applications,
DMDS results in performance levels that are generally superior to the other
products, such as terf-alkyl polysulphides.
[0004] However, these other products may have odorous levels that are lower
than that of DMDS and may, as a result, make their use preferred in certain cases.
[0005] Many processes for synthesizing organic sulphides and oxides thereof
exist today. The most widely used, and the most cost-effective from an industrial
I point of view, have however the disadvantage of resulting in by-products
responsible for the unpleasant odours of the final products.
[0006] For example, among the methods for synthesizing DMDS, a particularly
effective and economical method is the oxidation of methyl mercaptan by sulphur
according to the invention:
- 2 -
2CH3SH + S c a t a l y s t ^ CH3SSCH3 + H2S
[0007] This oxidation of methyl mercaptan by sulphur, catalysed by organic or
inorganic, homogeneous or heterogeneous, basic agents under batchwise or
continuous conditions, is accompanied by a release of hydrogen sulphide and of
dimethyl polysulphides (CHaSxCHa) with a sulphur rank x of greater than 2.
[0008] In order to manufacture DMDS according to this process with high yields
and a limited production of DMPS (dimethyl polysulphides with a rank greater than
2), patent EP0 446 109, the content of which is incorporated herein by way of
reference, describes a preparation process comprising two reaction regions
interrupted by an intermediate degassing region and followed by a distillation
region. Although giving a good performance level in terms of yield and selectivity
for DMDS, it is found that this process results in a not insignificant amount of
methyl mercaptan (MM, approximately 4000 ppm) and a very small amount of
dimethyl sulphide (DMS, approximately 300 ppm), originating from the methyl
mercaptan used or produced during the synthesis of DMDS, being left in the
finished product.
[0009] The result of these volatile impurities is that they render the odour of the
DMDS very unpleasant and aggressive and this strong odour is regarded as a
significant cause of trouble during the handling of this product by users.
[0010] In order to mask the odour of organic polysulphides, US patent 5 559 271
recommends adding thereto a certain amount of masking product such as, In
particular, vanillin or ethyl vanillin. Although its general formula includes DMDS,
this patent is more particularly directed towards the treatment of heavy
polysulphides, such as, for example, di-te/t-nonyl pentasulphide. The application
of this method to DMDS does not enable its unpleasant odour to be effectively
masked.
[0011] Patent EP 0 976 726 indicates that. In the specific case of DMDS having
reduced contents of highly odorous volatile impurities such as methyl mercaptan
and dimethyl sulphide, the most effective odour-masking agents are chosen from
the esters of general formula R^C02R^ in which R^ represents an optionally
unsaturated, linear or branched hydrocarbon-based radical containing from 1 to 4
- 3 -
carbon atoms, and R^ represents an optionally unsaturated, linear, branched or
cyclic hydrocarbon-based radical containing from 2 to 8 carbon atoms.
[0012] The solutions known today for masking the odours of organic sulphides
and oxides thereof are not, however, entirely satisfactory, and odour-masking
agents which are more effective, and in particular for which the odour smelt by the
final user is as pleasant as possible, are constantly being sought for these
products.
[0013] Thus, the subject of the invention is, inter alia, a composition comprising:
a) at least one organic sulphide, optionally in oxide form, of general formula (1):
R-S-Sx-R'
(o)„ ,,,
in which R is chosen from a linear or branched alkyl radical containing from 1 to 4
carbon atoms, and a linear or branched alkenyl radical containing from 2 to 4
carbon atoms; n is equal to 0, 1 or 2; x is an integer chosen from 0, 1, 2, 3 or 4,
preferably x represents 1, 2, 3 or 4; R' is chosen from a linear or branched alkyl
radical containing from 1 to 4 carbon atoms, and a linear or branched alkenylene
radical containing from 2 to 4 carbon atoms or, only when n = x = 0, a hydrogen
atom; and
b) at least one odour-masking agent comprising at least one monoester, at least
one di- and/or triester, at least one alcohol, at least one ketone and, optionally, at
least one terpene.
[0014] According to one preferred embodiment, the odour-masking agent
comprises:
b1) from 1% to 40% by weight of at least one monoester;
b2) from 10% to 70% by weight of at least one di- and/or triester;
b3) from 1% to 30% of at least one alcohol;
b4) from 0.5% to 20% of at least one ketone of formula R^-CO-R", in which
R^ represents a linear or branched hydrocarbon-based chain containing from 1 to
6 carbon atoms, optionally comprising one or more unsaturation(s) in the form of
one or more double bond(s), and R^ represents a cyclic hydrocarbon-based chain
or else a linear or branched hydrocarbon-based chain optionally, but preferably,
substituted with a cyclic structure, R'' containing from 6 to 12 carbon atoms,
optionally comprising one or more unsaturation(s) in the form of one or more
- 4 -
double bond(s) and being optionally substituted with one or more hydroxy! groups;
and
b5) optionally, up to 20% of at least one terpene.
[0015] In the description of the present invention, the percentages are indicated
by weight, unless specifically otherwise mentioned. The percentages of b1, b2, b3,
b4 and b5 are percentages by weight expressed relative to the total weight of the
odour-masking agent b). Unless otherwise mentioned, "ppm" means parts per
million by weight.
[0016] According to one embodiment, the component a) used in the composition
according to the present invention is an organic sulphide, optionally in oxide form,
obtained according to any process known per se, or else commercially available,
and preferably with a reduced content of volatile impurities. Such impurities are,
for example, methyl mercaptan (MM) and dimethyl sulphide (DMS) in the case of
DMDS; as regards DMSO, the impurities most commonly encountered are, for
example, DMS, DMDS and/or BMTM (bis(methylthio)methane, also known as 2,4-
dithiapentane).
[0017] Any method known to those skilled in the art for removing, or at the very
least reducing, the abovementioned volatile impurities may be suitable; among
said methods, mention may be made, in a nonlimiting manner, of distillation,
evaporation under a stream of inert gas such as nitrogen, air and the like.
[0018] In particular, the amounts of MM and of DMS present in the DMDS may
advantageously be greatly reduced by distillation. This method has the advantage
of jointly removing the MM and the DMS, whereas the usual methods for odour
reduction are generally based on the elimination of the residual mercaptans by
specific reaction of the mercaptan function with an eliminating agent such as a
base or an alkene oxide in the presence of a base. These methods would have no
effect on the DMS present in the DMDS.
[0019] According to one preferred embodiment, the residual contents of MM and
DMS, after topping of the DMDS, do not exceed 100 ppm and 50 ppm,
respectively, by weight relative to the DMDS. The residual content of methyl
mercaptan (MeSH) in the DMDS should not exceed 500 ppm by weight.
[0020] In the case of DMSO, the contents of impurities, such as DMS, DMDS
and/or BMTM, should advantageously be less than 100 ppm, preferably less than
- 5 -
50 ppm, more preferably less than 10ppm, for each of the impurities taken
separately.
[0021] In one embodiment, the component a) of the composition according to the
present invention corresponds to formula (1a):
R-S-Sx-R"
^°)" (1a)
in which R and R', which may be identical or different, are chosen from a linear or
branched alkyl radical containing from 1 to 4 carbon atoms, and a linear or
branched alkenyl radical containing from 1 to 4 carbon atoms; n is equal to 0; and
X is an integer chosen from 1, 2, 3 or 4, preferably 2, 3 or 4.
[0022] Preferably, the component a) of formula (1a) is DMDS.
[0023] In another embodiment, the component a) of the composition according to
the present invention corresponds to formula (lb):
R-S-Sx-R'
(°)" (ib)
In which R and R', which may be identical or different, are chosen from a linear or
branched alkyl radical containing from 1 to 4 carbon atoms, and a linear or
branched alkenyl radical containing from 1 to 4 carbon atoms; n is equal to 0, 1 or
2; and x is equal to 0.
[0024] Preferably, the component a) of formula (1b) is DMSO.
[0025] According to the invention, the masking of the odour of the organic
sulphide or of the organic sulphides, and/or of the oxide form(s) thereof,
corresponding to formula (1) described above, is obtained by addition, to said
sulphides or oxides, of a composition defined in b) above.
[0026] The present invention has the advantage of masking the unpleasant odour
of at least one organic sulphide and/or of the oxide(s) thereof, without chemically
modifying the nature thereof. Thus, the present invention proposes a composition
comprising a) a predominant amount of at least one organic sulphide of formula
(1) defined above, to which a minor amount of a composition b) masking the
unpleasant odour of the component a) is added.
[0027] The composition with masked odour according to the present invention
may be prepared according to any process known per se by simply combining at
- 6 -
least one component a) with at least one odour-masking composition b). It is, for
example, possible to add at least one composition b) to at least one component a),
or vice versa, optionally with stirring and/or optionally with heating. More generally,
any known mixing and/or heating method may be used.
[0028] The preparation of the composition according to the invention may, for
example, be carried out under atmospheric pressure, at a temperature of between
0°C and 100°C, preferably between ambient temperature and approximately SOX.
The preparation may also be carried out under pressure or at a reduced pressure,
at temperatures within the ranges indicated above.
[0029] The period of time required for the preparation of the composition with
masked odour according to the invention varies according to the nature and the
amount of the component(s) a) and of the composition(s) b) but also as a function
of the temperature and of the pressure selected. As a general rule, this period
corresponds to the period of time necessary for obtaining a homogeneous mixture
and producing the desired effect of masking the odour of the component(s) a); it is
generally between a few seconds and a few minutes, or even one or more hours.
[0030] The preparation process mentioned above can be prepared batchwise
(batch process) or else continuously.
[0031] The composition b) is mixed, according to any method known to those
skilled In the art, with the component a) in an amount ranging from a few ppm, for
example 10 ppm, to 2%, preferably from 10 ppm to 1% by weight relative to the
total weight of the composition. The amount of masking agent (composition b)) can
vary to a large extent within the range indicated above, depending on the desired
effect, the strength of the odour to be masked, the respective residual contents of
the various impurities that may be present in the component(s) a) defined above,
and the like.
[0032] Amounts of masking agent of less than a few ppm may be too small to
obtain the desired effect. Amounts of masking agent greater than 2% may have
harmful effects depending on the applications envisaged for the organic sulphides
and/or oxides.
[0033] In the case of DMDS, for example, one of the principal advantages of this
organic sulphide is the high sulphur content (68%). Too great a content of masking
- 7 -
agent in the composition would result in a decrease in this sulphur titre and would
reduce the advantage of this product in its principal applications.
[0034] Preferably, and by way of nonlimiting example, the content of odourmasking
agent(s) b) is between 0.001% and 0.5% by weight relative to the total
weight of the composition, and more particularly between approximately 0.1% and
0.5% by weight, advantageously equal to approximately 0.3%, in particular when
the organic sulphide of which it is desired to mask the odour is DMDS.
[0035] Also by way of nonlimiting example, in the case of DMSO, the maximum
content of odour-masking agent(s) is advantageously between 0.001% and 0.2%
by weight relative to the total weight of the composition, preferably between
100 ppm and 1000 ppm, for example approximately 500 ppm by weight.
[0036] As indicated above, the composition according to the present invention
comprises at least one composition of odour-masking agent b), said agent
comprising from 1% to 40%, preferably from 2% to 35%, more preferably from 5%
to 30% by weight, relative to the total weight of the composition b), of at least one
monoester mentioned in b1).
[0037] As illustrative but nonlimiting examples of monoesters mentioned in b1),
mention may be made of saturated or unsaturated C2-C20 acid esters, such as
ethyl, propyl, butyl, pentyi, 2-methylbutyl, isoamyl, hexyl, benzyl, phenylethyl,
menthyl or carvyl acetates, propionates, butyrates, methylbutyrates, pentanoates,
hexanoates, heptanoates, caproates, oleates, linoleates and linolenates, and the
like, and also mixtures thereof.
[0038] Isoamyl acetate, hexyl acetate, 2-methylbutyl butyrate, isoamyl butyrate,
benzyl acetate, phenylethyl acetate and mixtures of these compounds are more
particularly preferred.
[0039] The odour-masking agent composition b) also comprises at least one diand/
or triester b2), in an amount of between 10% and 70% by weight, preferably
between 15% and 65% by weight, more preferably between 20% and 60% by
weight, such as, in a nonlimiting manner, at least one di- and/or triester chosen
from o/tAjo-phthalates, such as diethyl o/YA)o-phthalate; citrates, such as triethyl
citrate; and malonates, such as diethyl malonate.
[0040] The odour-masking agent b) also comprises from 1% to 30%, preferably
from 5% to 25% by weight relative to the total weight of the composition, of at least
- 8 -
one alcohol b3), advantageously at least one monoalcohol containing from 1 to 30
carbon atoms, preferably from 6 to 20 carbon atoms, more preferably from 8 to 11
carbon atoms, said carbon atoms forming a linear or branched chain optionally
comprising one or more unsaturation(s) in the form of one or more double bond(s),
and optionally comprising a 5- or 6-membered cyclic structure which is saturated
or completely or partially unsaturated.
[0041] The alcohols defined above are preferably monoalcohols, the hydroxyl
function preferably being borne by an sp^ carbon atom. It should be understood
that the hydroxyl function may also be borne by a carbon atom included in a cyclic
structure as defined above.
[0042] The alcohols used in the odour-masking agent and as defined above are
advantageously, and by way of nonlimiting examples, chosen from menthol,
neomenthol, phenylethyl alcohol, benzyl alcohol, citronellol, dihydromyrcenol,
dihydroterpineol, dimetol, ethyllinalol, geraniol, linalol, tetrahydrolinalol,
tetrahydromyrcenol, nerol, and the like, and also mixtures of two or more thereof.
[0043] The ketone or the ketones Indicated in b4) above are chosen, by way of
nonlimiting examples, and preferably, from damascenes, damascenones, ionones,
irisones, methylionones, frambinone (CAS No. 5471-51-2), and the like, and also
mixtures thereof. The amount of ketone(s) is advantageously between 0.5% and
20%, preferably between 1% and 10% by weight relative to the total weight of the
composition.
[0044] The odour-masking agent may optionally also comprise up to 20%,
preferably from 1% to 10% by weight relative to the total weight of the
composition, of at least one terpene.
[0045] As examples of terpenes, indicated in b5), which can be used, mention
may be made, in a nonlimiting manner, of terpinenes, myrcene, limonene,
terpinolene, pinenes, sabinene, camphene, and the like, mixtures of two or more
thereof, and also essences based on terpenes, in particular those comprising
these ingredients.
[0046] In addition, the odour-masking agent that can be used in the context of the
present invention may comprise, in minor amounts, other agents (fragrances)
customarily used in the perfumery field, and in particular one or more compounds
bearing cyclic ketone and/or aldehyde function(s), among which mention may be
- 9 -
made, in a nonlimiting manner, of geranial, neral, citronellal, menthone,
isomenthone, 1,8-cineole, ascaridole, flavonone, and mixtures thereof.
[0047] The composition b) intended to mask the odour of the organic sulphides,
and as described above, may, where appropriate, or if necessary, also comprise
one or more additives commonly used in the field. Such additives may, for
example, be chosen, in a nonlimiting manner, from solvents, pigments, dyes,
preservatives, biocides and the like.
[0048] Among the solvents, most particularly preferred examples are alcohols,
ethers, esters and glycols. Particularly advantageously, the solvent is chosen from
diethyl phthalate, ethylene glycol, propylene glycol, diethylene glycol, dipropylene
glycol, polyethylene glycols, polypropylene glycols, and mixtures thereof, and even
more advantageously from diethyl phthalate, dipropylene glycol, and mixtures
thereof.
[0049] It should be understood that a monoester, diester or triester present in the
odour-masking agent composition b), as component b1) and/or b2), may also have
the functions of the solvents defined above.
[0050] A typical odour-masking agent composition suitable for organic sulphides
and oxide forms thereof, according to the present invention, comprises by weight:
- from 5% to 30% by weight of at least one monoester b1), chosen from
isoamyl acetate, ethyl 2-methyl butyrate, isoamyl butyrate, phenylethyl
acetate, ethyl caproate, benzyl acetate, hexyl acetate and mixtures thereof;
- from 20% to 60% by weight of at least one di- and/or triester b2) chosen from
o/t/70-phthalates, such as diethyl orf/7o-phthalate; citrates, such as triethyl
citrate; and malonates, such as diethyl malonate, and mixtures thereof;
- from 5% to 25% of at least one alcohol, preferably of at least two alcohols,
more preferably of at least three alcohols, as described above in b3);
- from 1 % to 10% of at least one ketone, preferably at least two ketones, more
preferably at least three ketones, as described above in b4); and
- from 1% to 10% of at least one, preferably at least two, preferably a mixture
of, terpene(s) referenced above in b5).
[0051] This composition, denoted Ci in the rest of the present disclosure, is most
particularly suitable for masking the odour, or for improving the odour, of DMDS.
- 1 0 -
This same composition Ci may also be advantageously used for masking or
improving tlie odour of DMSO.
[0052] A representative but nonlimiting example of such a composition CI is
reproduced below, in which each of the components comprises one, several, or
even all the compounds listed:
Component b1) 16.00%
comprising benzyl acetate, hexyl acetate,
isoamyl acetate, phenylethyl acetate,
ethyl caproate, ethyl 2-methyl butyrate
Component b2) 50.00%
comprising diethyl malonate, diethyl
phthalate
Component b3) 20.60%
comprising phenylethyl alcohol, citronellol,
geraniol, linalol, cis-3-hexenol
Component b4) 4.50%
comprising 1 -(4-hydroxyphenyl)butan-3-one,
a/pA?a-irisone
Component b5) 7.00%
orange terpenes
Others 1.90%
comprising citral, ethylmaltol, ethylmethyl
phenylglycidate
[0053] These compositions are given by way of examples and are in no way
restrictive with regard to the potential diversity of compositions permitted by the
present invention defined by means of the attached claims.
[0054] The following examples illustrate the invention without limiting it.
Example 1: DMDS composition withi masited odour
[0055] In order to characterize a fragrancing composition making it possible to
mask or improve the odour of DMDS, an olfactory test procedure was set up. This
procedure makes it possible to classify various formulations hedonically.
- 1 1 -
Operating conditions:
[0056] In order to carry out this olfactory test, 30-litre polyethylene (PE) drums are
used, each equipped with a lid in which a trap door of approximately 10 cm x
10 cm is cut, allowing an operator (panellist) to smell the vapours contained in the
drum.
[0057] A crystallizing dish containing two sheets of absorbent paper
(chromatography paper) is placed in each of the drums. 1 ml of test composition is
poured onto each sheet. The drums are stored closed for 24 hours at ambient
temperature. The evaluation is subsequently carried out blind.
[0058] The panellists, of which there are ten, come in turn to test a few products
per session (a maximum of three products per session). They begin by smelling
the drum containing the reference DMDS for this study, and then one of the test
compositions.
[0059] The panellists assign, according to their preference, a score to each of the
test compositions, relative to the reference which arbitrarily received the score 5.
The scores given by the panellists range from 1 (the most pleasant product) to 10
(the most unpleasant product).
Preparation of the test samples:
[0060] The DMDS, without odour-masking agent, is an industrial DMDS produced
by Arkema, has a purity of greater than 99.7% and contains less than 100 ppm of
methyl mercaptan and less than 50 ppm of dimethyl sulphide.
[0061] Added to this DMDS are 3000 ppm of a fragrancing composition having
the following composition: 25% isoamyl acetate, 50% diethyl ortho-phthalate, 15%
2-methylbutyl butyrate and 10% benzyl acetate, as described in patent
EP 0 976 726. This sample is the reference sample for the olfactory test and is
called: A1.
[0062] 3000 ppm of the fragrancing composition Ci according to the invention and
defined above are added to the same industrial DMDS produced by Arkema
without odour-masking agent. This sample is called: A2.
Results:
[0063] The results of the olfactory test are reproduced in table 1 below:
- 1 2 -
- Table 1 -
Test sample Mean Standarddeviatlon Group
Ai 5 0 A
Az I 2.83 I 0.96 I B
[0064] Statistical treatment of these results makes it possible to calculate the
standard deviation and to classify the samples in two groups by studying the SSD
(Smallest Significant Difference) given in this test at 0.87.
[0065] The SSD test is a statistical test for comparison of means and makes it
possible to determine whether or not the means of two samples are significantly
different, from a statistical point of view.
[0066] In the examples of the present invention, the statistical condition used is
fixed at 95%. If the means are not significantly different, the two samples are
classified in the same group. If the means are significantly different, the two
samples constitute two separate groups (A and B in the examples that illustrate
the invention).
[0067] The same operation is carried out in order to compare all the samples,
thereby making it possible, ultimately, to obtain one, two or more groups, each
constituting samples of which the mean scores are not significantly different.
These various treatments are carried out using the FIZZ software, version 2.01
(Biosystemes, Couternon, France).
[0068] There is therefore a very significant statistical difference indicating a much
more pleasant perception of the odour of the sample A2 than of the sample Ai.
Example 2: DMSO composition with masl^ed odour
[0069] An olfactory test similar to that described in example 1 is carried out,
taking DMSO as base, in place of DMDS.
Preparation of the test samples:
[0070] The reference DMSO is an industrial DMSO with a purity equal to 99.97%,
produced by Arkema, and then supplemented with 50 ppm of dimethyl sulphide
(DMS). This sample is called B1.
- 1 3 -
[0071] 700 ppm of the fragrancing composition Ci according to tlie invention are
added to the same batch of DMSO supplemented with 50 ppm of dimethyl
sulphide. This sample is called B2.
[0072] The results of the olfactory test are reproduced in table 2 below:
- Table 2 -
Test sample Mean Standarddeviation Group
B^ 5,93 133 A
Bz I 2.75 I 1.52 I B
[0073] As for example 1, the statistical treatment of these results makes it
possible to calculate the standard deviation and to classify the samples in two
groups by studying the SSD (Smallest Significant Difference) given in this test at
1.01.
[0074] There is therefore a very significant statistical difference indicating a much
more pleasant perception of the odour of the sample B2 than of the sample B1.
Example 3: DMSO composition with masl^ed odour
[0075] The same industrial DMSO as that of example 2, with a purity of 99.97%,
produced by Arkema, is tested without the addition of the 50 ppm of DMS,
according to the olfactory test described in example 2. This sample is called 01.
[0076] 150 ppm of the fragrancing composition Ci according to the invention are
added to this same industrial DMSO. This sample is called 02.
[0077] The results of the olfactory test on 01 and 02 indicate that the sample 02
is judged to be statistically much more pleasant than the sample Oi.

- 14-
CLAIMS
1. Composition comprising:
a) at least one organic sulphide, optionally in oxide form, of general formula
(1):
R-S-Sx-R"
(o)„ ,,
in which R is chosen from a linear or branched alkyl radical containing from
1 to 4 carbon atoms, and a linear or branched alkenyl radical containing
from 2 to 4 carbon atoms; n is equal to 0, 1 or 2; x is an integer chosen from
0, 1, 2, 3 or 4, preferably x represents 1, 2, 3 or 4; R' is chosen from a linear
or branched alkyl radical containing from 1 to 4 carbon atoms, and a linear
or branched alkenylene radical containing from 2 to 4 carbon atoms or, only
when n = x = 0, a hydrogen atom; and
b) at least one odour-masking agent comprising at least one monoester, at
least one di- and/or triester, at least one alcohol, at least one ketone and,
optionally, at least one terpene.
2. Composition according to Claim 1, in which the component a) is chosen
from dimethyl disulphide and dimethyl sulphoxide.
3. Composition according to Claim 1 or 2, in which the odour-masking agent
comprises:
b1) from 1% to 40% by weight of at least one monoester;
b2) from 10% to 70% by weight of at least one di- and/or triester;
b3) from 1% to 30% of at least one alcohol;
b4) from 0.5% to 20% of at least one ketone of formula R^-CO-R^ in which
R^ represents a linear or branched hydrocarbon-based chain containing
from 1 to 6 carbon atoms, optionally comprising one or more
unsaturation(s) in the form of one or more double bond(s), and R''
represents a cyclic hydrocarbon-based chain or else a linear or branched
hydrocarbon-based chain optionally, but preferably, substituted with a cyclic
structure, R** containing from 6 to 12 carbon atoms, optionally comprising
- 1 5 -
one or more unsaturation(s) in the form of one or more double bond(s) and
being optionally substituted with one or more hydroxyl groups; and
b5) optionally, up to 20% of at least one terpene.
4. Composition according to Claim 3, in which the odour-masking agent b)
comprises from 1% to 40%, preferably from 2% to 35%, more preferably
from 5% to 30% by weight, relative to the total weight of the composition, of
at least one monoester b1), chosen from saturated or unsaturated C2-C20
acid esters, such as ethyl, propyl, butyl, pentyl, 2-methylbutyl, isoamyl,
hexyl, benzyl, phenylethyl, menthyl or carvyi acetates, propionates,
butyrates, methylbutyrates, pentanoates, hexanoates, heptanoates,
caproates, oleates, linoleates and linolenates, and the like, and also
mixtures thereof.
5. Composition according to Claim 3, in which the odour-masking agent b)
comprises at least one di- and/or triester b2), in an amount of between 10%
and 70%, preferably between 15% and 65%, more preferably between 20%
and 60% by weight, chosen from OAtrto-phthalates (preferably diethyl orthophthalate),
citrates (preferably triethyl citrate) and malonates (preferably
diethyl malonate).
6. Composition according to Claim 3, in which the odour-masking agent b)
comprises from 1% to 30%, preferably from 5% to 25% by weight relative to
the total weight of the composition b), of at least one alcohol b3),
advantageously at least one monoalcohol containing from 1 to 30 carbon
atoms, preferably from 6 to 20 carbon atoms, more preferably from 8 to 11
carbon atoms, said carbon atoms forming a linear or branched chain
optionally comprising one or more unsaturation(s) in the form of one or
more double bond(s), and optionally comprising a 5- or 6-membered cyclic
structure which is saturated or completely or partially unsaturated.
7. Composition according to Claim 6, in which the alcohol is chosen from
menthol, neomenthol, phenylethyl alcohol, benzyl alcohol, citronellol.
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dihydromyrcenol, dihydroterpineol, dimetol, ethyllinalol, geraniol, linalol,
tetrahydrolinalol, tetrahydromyrcenol, nerol, and the like, and also mixtures
of two or more thereof.
8. Composition according to Claim 3, in which the odour-masking agent b)
comprises between 0.5% and 20%, preferably between 1% and 10% by
weight relative to the total weight of the composition b), of at least one
ketone b4) chosen from damascenes, damascenones, ionones, irisones,
methylionones and frambinone, and the like, and also mixtures thereof.
9. Composition according to Claim 3, in which the odour-masking agent b)
optionally comprises up to 20%, preferably from 1% to 10% by weight
relative to the total weight of the composition, of at least one terpene b5),
chosen from terpinenes, myrcene, limonene, terpinolene, pinenes,
sabinene, camphene, and the like, mixtures of two or more thereof, and
also essences based on terpenes, in particular those comprising these
ingredients.
10. Composition according to any one of the preceding claims, in which the
odour-masking agent comprises by weight:
-from 5% to 30% by weight of at least one monoester b1), chosen from
isoamyl acetate, ethyl 2-methyl butyrate, isoamyl butyrate, phenylethyl
acetate, ethyl caproate, benzyl acetate, hexyl acetate and mixtures thereof;
- from 20% to 60% by weight of at least one di- and/or triester b2) chosen
from o/trto-phthalates (preferably diethyl orfA70-phthalate), citrates
(preferably triethyl citrate) and malonates (preferably diethyl malonate), and
mixtures thereof;
- from 5% to 25% of at least one alcohol, preferably of at least two alcohols,
more preferably of at least three alcohols, bS);
-from 1% to 10% of at least one ketone, preferably at least two ketones,
more preferably at least three ketones, b4); and
-from 1% to 10% of at least one, preferably at least two, preferably a
mixture of, terpene(s), b5).
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11. Composition according to any one of the preceding claims, in which the
masl