Note: Descriptions are shown in the official language in which they were submitted.
8~1
J.717
ORA~ PRODUCTS SUC~ AS DENTIFRICES AND MOUT~WAS~ES
AND TEEIR PREPARATION
This invention relates to oral products such as
dentifrices and mouthwashes.
The incorporation o~cationic germicides, e.g. bis-
biguanido-hexane anti-bacterial agent~ such as
cblorbexidine (Eibitane - Trade Mark), into oral products
is known. Numerous dentifrices containin~ chlorhexidine
have been disclosed, for example in UE Patent Specification
No. 825,577t published Netherlands Patent Applications Nos.
72-03852 and 72-03853, Austrian Speciiioation No. 327,393,
and in US Patent Specification No. 3,925,543. The use of
chlorhexidine-containin~ mouthrinses has also been exten-
sively described: see for example H. Loe, Govt. Reps.
Announc. ~1975) 7S (2), 47, and Chem. Abs. (1975), 82,
165018t.
11'~0~36~
- 2 - J.717
A variety of other such cationic germicides is also
known: see for example Belgia:n Patent No. 847,735, West
German OS-23 13 830, UK Specification No. 1,398,058 and
US Patent No. 4,059,687.
The use of such cationic germicides in oral prodqcts
has been found to reduce gingivitis and the accumulation of
dental plaque.in the mouths of u9ers.
Nevertheless, the acceptability to potential users of
oral preparations containing many of such cationic germicides
has been substantially limited by their bitter taste.
- We find that attempts to circumvent this limitation
by formulating oral compositions with strong competing
flavours generally do not succeed. For example, it has
been found that the addition o~ substantial quantities Or
aniseed, vanilla or vanillin, or wi.ntergreen flavours, results
in compositions still possessing unpleasant and unacoeptable
bitter tasteinspite ofthe prQsenceoftbesestron~ flavaurants.
We have now found that there are flavourants whi~b have
a sufficiently pronounced masking ac-tion on the bitter.
.
flavaur of bitter-tasting cationic germicides to al~ow the
preparation of oral products which contain the~e bitter
subsbances together with bitterness-mas~ing flavourants in
effective amounts so that the products have an overall
flavour acceptable to the potential user. We bave found
bitterness_masking flavourants that do not merely add to
and compete with the bitter taste o~ the germicides, as do
the unsuccessful flavours mentioned àbove: they have
unexpectedly been -found -to mask the bitterness,
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Accordin~ly the invention provides an oral product
(such as a dentifrice or a mou-th~ash) containing a bitter
-tasting cationic germicide together with a bitterness-
masking amount of a flavourant capable of masking the
bitter taste of the germicide. The bitterness-maskin~
flavourant can for example be a flavouring mixture comprising
a plurality of flavouring con~tituents including at least
one such bitterness-masking flavourant. A suitable such
bitterness-masking flavouring constituent is one or more
selected from essential citrus oils (other than lime oil),
and benzyl salicylate and anisic alcohol. The citrus
oil may be an essential citrus oil of natural origin
(which is itself a complex mixture of organic compounds),
but a synthetic or artificïàl citrus oil, e.g. a synthetic
- 15 lemon oil composition formulated to approximate the n~tural
essential oil in note, may also be used.
Benzyl salicylate and anisic alcohol are of respçctive
formulae (I) and (II):
~0\ - ' .
~ CH2ØC0 ~ (I) CH30 ~ C~20H (II)
Particqlar examples Or suitable flavoured formulations
of the oral products according to the invention incorporate
essen-tial oil of lemon, orange, grapefruit or mandarin to
reduce the bitter impre~ion o~ the a~tibacterial agent.
In many preferred formulations of the oral products
according to the invention, the bitterness-masking flavourant
.. . . . .
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~ J.717
will be present in a mixture of flavourants which confers
upon the final formulation an overall flavour note
different from that of the bitterness-masking flavourant
incorporated therein. Thus, the citrus oil, other than
lime oil, and/or the benzyl salicylate and/or anisic
alcohol, may be added to an oral product as a supplement
to or replacement for part of a conventionally used
flavourant, which itself is generally a complex mixture of
organic compounds. For example, an appropriate citrus oil
may be present in an oral product according to the invention
as part of a flavourant mix-ture of which it constitutes a
minor or a major proportion,e.g. up to 30%~ for example
2-24%~ suitably about 12% by weight. Such an oral product
may have for example an ovérall citrus flavour, e.g. lemon
flavour, but it may alternatively possess an overall flavour
different from citrus flavour, e.g. a minty flavour: indeed
such a result may be preferred.
It is of course understood that each individual
flavourant composition to be used in an oral product in
accordance with the invention can be adjusted in overall
flavour note as desired in accordance with the normal
flavourist's practice of balanoing the proportions of
individual constituents to produce an acceptable overall
result. The distinctive feature of this invention will
-then be seen in the use of an e-ffective amount of the citrus
oil (except lime oil), benzyl salicylate and/or anisic
alcohol as a masking flavourant component or components,
in combination with a possibly large number of other
-` llZ1~861
- 5 - J.717
in~ividual ~lavour componell-ts or a proprietary or other
collll)lex flavo~rant mixture.
Under these circumstances, we have produced useful
flavourant mixtures for use according to the invention
containing (for example) from 0.1-5% benzyl salicylate or
anisic alcohol, (based on the weight o~ the flavourant
mixture). Examples of such mixtures as given below
include for example l~o benzyl ~alicylate.
The citrus oils, e.g. orange and lemon oil, have for
example been used with success at levels of 2-30~, based
on the weight of the flavourant mixture. The lowest
levels of this range, e.g. 2-5%~ have for~example (but
not necessArily) been chosen where the flavourant mixture
also contains benzyl salicylate or anisic alcohol. Where
tbe orange or lemon or other citrus oil (except lime oil~
i~ used in the absence of benzyl salicylate or anisic
alcoholJ we have some preference for usin~ the higher
levels in the range, e.g. above 5~, especially above 10%.
Suitable co_ilavourants *or use in the flavourant mixtUres
include for example those which impart a fresh, cool
flavour to the oral product, e.g. menthol or oil of
peppermint. However~ many other materials well known to~
the flavourist nay also be u~ed. ~he amount of the
flavourant mixture to be used in oral compositions in
25 accordance with this invention may be fixed at any desired
(e.g. a conventional) level. 0.5-2% by weight of the
flavourant mixture with respect to the whole composition
.. .... .... .. ...... ... . . ... . ..... . .. . .. . . . . .. . .. .
- 6 - J.717
may for example be chosen. Dentifrices will commonly be
fla~ouredat levels of forexample 0.6-1.55~,especiallyabout
15~flavourantmixturebyweightbased onthewhole formulation.
The bitter-tastin~ cationic germicide to be used in
S the compositions o~ the invention, and of which the bitter
taste i~ to be masked in accordance with the invention, can-
suitably be any of the bitter-tasting biguanide germicides,
e.g. compounds containing a single alkyl- or aryl-substi-
tuted biguanide group; compounds containing two alkyl- or
aryl-substituted biguanide groups joined by a bridging group;
polymers containing a number of biguanide groups joined by
bridging groups, and modiiied biguanide compounds in which
nitrogen atoms Or the biguanide groups are replaced by
heteroatoms such as oxygen or sulphur. Biguanides
described in the prior specifications cited at the head o~
this specification are among the examples of such compounds.
Particularly convenient e~amples of the cationic
germicide used in the oral product are 1,6_bis-(~-chloro-
phenylbiguanido)_hexane (chlorhexidine), and 1,6_bis_
(2-ethylhexylbiguanido)hexane (alexidîne). ~hese are
conventionally used as water soluble salts, e.g. gluconates.
~ he amount o~ the cationic germicide to be inoluded in
the composition can be chosen according to convenience and
- can ~or example be in the range 0.1-2% by weigbt. The
level chosen will generally be a compromise: at low levels
there will be encountered the lower activity limit under the
particular circumstances of use, and at high levels the
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- 7 - J.717
bitterness to be maslted will of course be greater, as will
th~stain-promoting e~fec-l;of the germicide. Thedentifrices
pr~ferably con-tain 0.4~ germicide or more, e.g. 0.8~:
the mouthwashes can if desired be formulated at 0.1-0.2%
with good results, tho~gh levels up to 1% give increased
anti_bacterial effect.
The oral prodqcts of this invention can contain, apart
from the ingredients with which this invention is concerned,
conventional ingredients such as abrasives, hqmectants,
thickeners, whiteners and others known to those skilled in
this ~ield. These aspec-ts o~ the cholce o~ formulation
~orm no part of this invention.
The following Examples show the preparation of
selected formulations ~alling within the scope of this
invention. All peroentages given are by weight.
~ Examples 1-5
In each of Examples 1-5, a flavourant formulation
as detailed below was compounded, and incorporated at a
level o~ lyo by weight in a toQthpaste ~ormulation o~
which the remaining 99~ of the composition was as ~ollows: ` -
-
~a fr~yc~/rafe
Cibb~ito (ulpha-ulumina trih~dr~e)- 0
(average particle size 15/u) 55'
Glycerine 27.0
Hydroxyethyl cellulose 1.1
2S Chlorhexidine gluconate 0.8
Titanium dioxide 0.5
Water 14.6
2~3~61
- 8 - J.717
The flavourant formulations used to provide masking
of the bit-ter chlorhexidine taste in accordance with the
invention were of the following composition, referred to
each Example: -
Example 1:
~, .
Menthol 16.0
Anethole 10.0
Cineole 10.0
Menthone 1.2
Eugenol 1.0
Orange oil 1.0
Spearmint oil 10.0
-: Lemon oil ~ 2.0
Peppermint oil 47.6
Ben~yl salicylate . 1.0
Ethyl maltol 0.2
100.O
- Example 2:
Menthol 12.0
Anethole 10.0
Cineole 15.0
Lemon oil ..19.0
~5 Peppermint oil 34.0
Methyl salicylate 8.0
.
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_ 9 ~ J. 717
Exarllple 2 (contcl. ):
Thyme oil 1.0
Citral 1.0
100.0
Menthol 17.8
Anethole 5.6
Cineole 6.7
Peppermint oil . 42.9
Methyl salicylate 14.4
Mandarin oil 1.1
Grapefrqit oil 11.1
Ethyl vanillin 0.4
100 . O
Example 4:
Menthol 15.0
: 20 Anethole ~ 5.0
Cineole 5.0
Spearmint oil 15.0
Peppermint oil 50.0
Benzyl salicylate 1.0
Ethyl maltol . o.~
Menthone 1.6
: Eugenol .7.0
100.O
.
861
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Example 5:
~lenthol 20.0
Anethole 4.0
s Cineole 16.0
Menthone 1.0
Eugenol 1.0
Orange oil 2.0
Lemon oil 3.8
Spearmint oil 9.0
Ethyl maltol 0.2
Peppermint oil 42.0
Methyl salicylate 1.0
100 . 0
Each ~lavourant composition masked the bitterness of
the chlorhexidine cationic germicide in the dentifrice
formulation, and con~erred an overall peppermint ~lavour on
~: the ~ormula.tion.
E~amples 6~8
Mouthwa.shes:
In each of Examples 6-8 ~ a. mouthwash was formulated
to contain 0~2yo of a bitter-tasting cationic ~ermicide as
detailed below and 0.80/D of a flavourant mixture, also as
. detailed below, to mask the bitterness in accordance with
this invention: remaining constituents were: ethanol 18%~
nonionic sur~actant 1%, glycerine 12~, distilled water to
10~% .
llZ~8~
~ J.7].7
Cationic ~ermicide Flavourant mixture
( O . 2% ) 1~ . 8% )
Example 6 chlorhexidine as in Example 1 .
Example 7 alexidine as in Example 4
Example 8 chlorhexidine as in Example 5
In each preparation the flavourant mixture masks thc
bitter taste of the cationic germicide, and confers an
overall peppermint flavour on the preparatlon.
.
.
