FORM - 2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See Section 10 and Rule 13)
A DENTIFRICE COMPOSITION COMPRISING POLY-ETHYLENE-GLYCOL AND A
COOLING AGENT
HINDUSTAN UNILEVER LIMITED, a company incorporated under
the Indian Companies Act, 1913 and having its registered office at 165/166, Backbay Reclamation, Mumbai -400 020, Maharashtra, India
The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF INVENTION
The present invention relates to dentifrice compositions; particularly to dentifrice compositions in the form of a gel.
The invention has been developed primarily for use in dentifrices, and will be described hereinafter with reference to this application. However, it will be appreciated that the invention is not limited to this particular field of use.
BACKGROUND AND RELATED ART
Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of the common general knowledge in the field.
Self-heating dentifrices are known in the art. Two types of heating, or warming agents are generally included in dentifrices. They are, thermal warming agents, and chemo-warming agents. Thermal-warming agents are heat-generating substances, i.e. exothermic agents, (e.g. those which generate heat upon hydration). Consumer satisfaction with a product is likely to be high if some type of sensory signal exists to remind the consumer that the product is working; and it is inter-alia for this reason that warming agents are included in oral-care compositions; more particularly in dentifrices. Some known thermal warming agents are synthetic Zeolites, Sodium carbonate, Calcium chloride, Magnesium sulphate, and Polyols such as Polyethyleneglycol (commonly

and hereinafter referred to as PEG), Glycerol and Sorbitol. On the other hand, chemo-warming agents include Vanillin and related compounds, Pepper extract, Capsicum extract and Zingiber extract.
Dentifrices having a combination of two warming agents are also known in the art. WO1997/049374 (Henkel KGAA) discloses heating toothpastes having 20-85 weight% polyol of the Ethylene glycol, Propylene glycol or Glycerine group and 1-20 weight% of a dehydrated salt selected from Magnesium sulphate, Magnesium chloride or Calcium chloride.
Cooling agents such as menthol, isopulegol, 3-(l-menthoxy)propane-1,2-diol, 3-{1-menthoxy)-2-methylpropane-1,2-diol, p-menthane-2,3-diol, p-menthane-3,8-diol, Japanese mint (Mentha arvensis) oil, peppermint oil, menthone, menthone glycerol ketal, menthyl lactate, 3-(l-menthoxy)ethan-1-ol, 3-(1-menthoxy)propan-1-ol and spearmint oil are also commonly added to dentifrices. Some N-substituted-p-menthane-3-carboxamides found useful are those described in US4136163 (1979, WILKINSON SWORD LTD) and US4230688 (1980, WILKINSON SWORD LTD). N-ethyl-p-menthane-3-carboxamide is commercially available as WS-3™ Ex. Wilkinson Sword. Certain other cooling agent include N-2,3-trimethyl-2-isopropylbutanamide (WS-23™) , menthyl lactate (FRESCOLAT™ ML), menthone glycerine acetal (FRESCOLAT™ MGA), mono-menthyl succinate (PHYSCOOL™) , mono-menthyl glutarate, O-menthyl glycerine (COOL ACT™ 10), menthyl-N,N-dimethylsuccinamate and 2-sec-butylcyclohexanone (FRESKOMENTHE™) . In recent literature, some new cooling agents have been described in US2006/0276667 (Givaudan-SA)

which relates to novel N-substituted p-menthane Carboxamides; and WO2007/019719 (Givaudan-SA) which describes novel Carboxamide based cooling agents.
Dentifrices providing both hot and cool sensations have also been disclosed. Such dentifrices usually provide a first "warm feeling" followed by a second "cool feeling" lasting for about 30 minutes post brushing.
JP 2001/072547 (Kanebo LTD) discloses a combination of PEG as a thermal warming agent, red pepper powder or capsicum tincture as a calefacient agent (producing the sensation of heat when applied to the body} and 0.001 to 5 weight% 3,1-menthoxypropane-1,2-diol as a cooling agent. The disclosed compositions provide both hot and cold sensations to the user. The cooling sensation afforded by methoxypropane-1,2-diol is relatively lower in intensity.
JP 2006/117610A (Pola Chem Industries INC) discloses gel-form cosmetics, which impart hot and cold sensation. In this patent, Glycerol, Diglycerol and Polyethyleneglycol at 60 to 90 weight% have been used as thermal warming agents, whereas, menthol and glycerol mono-menthyl ether have been used as coolants.
US2004/202698 Al (Procter & Gamble) discloses orally consumable drug delivery systems for curing sleep disorders. The drug delivery systems are made of edible films that contain encapsulated pharmaceutical active. PEG has been described as one agent amongst several hydrophilic and hydrophobic materials, that may be used to make the films. Similarly, Carboxamide WS-3® has been described as one active

agent. The application does not describe a dentifrice that includes a Polyethyleneglycol and a N-substituted p-menthane Carboxamide.
WO 2005/04953 Al (Givaudan) describes various N-substituted p-menthane Carboxamides, but it does not disclose a dentifrice having 40 to 60 weight% Polyethyleneglycol or a derivative thereof; and 0.01 to 2 weight% N-substituted p-menthane carboxamide.
US 4136163 (Wilkinson Sword LTD) discloses N-substituted p-menthane-3-carboxamides. This is a generic description of the preparation and use of such molecules, that are said to be cooling agents. This patent also does not disclose a dentifrice having 40 to 60 weight% Polyethyleneglycol or a derivative thereof; and 0.01 to 2 weight% N-substituted p-menthane carboxamide.
Thus, it may be seen that the prior art is replete with disclosures of PEG or related/analogous compounds (polyols) being used as thermal warming agents, particularly in dentifrices. The prior art also discloses its combination with cooling agents.
The present inventors have observed that amongst the known thermal-warming agents, Polyethyleneglycol provides desirable degree of warming effect. However, it was also observed that dentifrice compositions containing Polyethyleneglycol, especially at relatively high levels, have an unpleasant bitter taste. The inventors could not find a prior-art that solves this problem of bitter taste associated with Polyethyleneglycol.

Thus, there exists an unmet need for a solution for the above-mentioned problem.
OBJECT OF THE INVENTION
It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art.
It is an object of the present invention to provide a dentifrice composition that includes relatively high levels of Polyethyleneglycol or a derivative thereof; while still exhibiting relatively low bitterness.
Other objects of the present invention will become apparent to those skilled in the art by reference to the specification.
The present inventors have surprisingly found that the bitter taste associated with dentifrice compositions which contain Polyethyleneglycol can be effectively masked when the dentifrice contains a N-substituted p-menthane Carboxamide. The resultant dentifrice compositions provide a rapid, but pleasant warming effect, followed by an intense, and relatively long-lasting cooling effect, thereby providing a dentifrice with a much sought-after, dual sensory property.
SUMMARY OF THE INVENTION
According to a first aspect, the present invention provides a dentifrice composition which includes 40 to 60 weight%

Polyethyleneglycol or a derivative thereof; and 0.01 to 0.2 weight% N-substituted p-menthane carboxamide.
Preferably the molecular weight of the Polyethyleneglycol is in the range of 400 to 600 g/mol.
Preferably Polyethyleneglycol or the derivative thereof is in the range of 50 to 55 weight%.
Preferably the N-substituted p-menthane carboxamide is N-p-benzeneacetonitrile p-menthane carboxamide, also known as N-(4-cyanomethylphenyl) p-menthane carboxamide.
Preferably the composition includes 0.1 wt% to 5 weight% Zinc salt.
According to a second aspect, the invention relates to use of a dentifrice composition of the first aspect for providing in-use warming sensation and cooling sensation.
The term "comprising" is meant not to be limiting to any subsequently stated elements but rather to encompass non-specified elements of major or minor functional importance. In other words the listed steps, elements or options need not be exhaustive. Whenever the words "including" or "having" are used, these terms are meant to be equivalent to "comprising" as defined above.
Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material ought to be understood as modified by the word "about".

It should be noted that in specifying any range of concentration or amount, any particular upper concentration can be associated with any particular lower concentration or amount.
For a more complete understanding of the above and other features and advantages of the invention, reference should be made to the following detailed description of preferred embodiments.
DETAILED DESCRIPTION OF THE INVENTION
The term "weight%" used throughout the specification means percentage by weight.
The term "PEG" and Polyethyleneglycol have been used interchangeably in the specification.
It is preferred that the degree of warming should be such that upon normal use of the dentifrice, the temperature of the dentifrice/saliva mixture and the resultant foam generated due to agitation, in the oral cavity reaches, within 30 seconds, for example, a value of 37 to 39 °C. Too high a temperature should be avoided, as this may cause an unpleasant sensation in the mouth. Preferably the difference between the initial temperature and the increased temperature should be no more than 5 °C, and more preferably should be in the range of 0.4 to 2 °C. By the choice of the amount of Polyethyleneglycol or derivative thereof, the degree of warming in the oral cavity can be controlled. In general, the amount of Polyethyleneglycol or a derivative thereof is 40 to 60 weight%, and more preferably in the

range of 50 to 55 weight%. It is to be noted that if the dentifrice contains optional ingredients which upon hydration or solution absorb heat, the amount of the PEG or the derivative thereof will be at the higher end of these ranges to compensate for this heat absorbed and to still provide the self-heating effect.
It is preferred that the molecular mass of Polyethylene glycol is in the range of 200 to 400 g/mol; more preferably in the range of 400 to 600 g/mol. It has been observed that PEG having molecular mass 600 g/mol is the least bitter of all. Instead of, or in addition to PEG, the composition may include a derivative thereof. The preferred derivative of Polyethyleneglycol is Polyethyeleneglcyol mono methyl ether, further preferably having molecular mass 550 g/mol. A combination of PEG of different molecular masses, or a combination of PEG with a derivative of PEG may also advantageously be used.
N-substituted p-menthane carboxamide
Preferred N-substituted, p-menthane carboxamides have been
described in greater detail in US2006/0276667 (Givaudan-SA),
which is incorporated herein by reference. Preferred
carboxamides include:
N-(4-cyanomethylphenyl) p-menthanecarboxamide,
N-(4-sulfamoylPnenyl) p-menthanecarboxamide,
N-(4-cyanophenyl) p-menthanecarboxamide,
N-(4-acetylphenyl) p-menthanecarboxamide,
N-(4-hydroxymethylphenyl) p-menthanecarboxamide and
N- (3-hydroxy-4-methoxyphenyl) p-menthanecarboxamide.

Particularly preferred is N-(4-cyanomethylphenyl) p-menthanecarboxamide, equivalently also known as N-p-benzerieacetonitrile p-menthane carboxamide.
These compounds are usually added in the form of a flavour composition. It is preferred that the flavour composition is in the range of 0.8 to 1.5 weight%. The flavour composition is available from Givaudan. Preferred level of N-substituted, p-menthane carboxamide in the dentifrice composition is from 0.05 to 0.15 weight%.
The dentifrice composition preferably includes 8 to 15 weight% humectant selected from glycerine, sorbitol or propylene glycol. The preferred humectant is glycerine.
It is preferred that the composition includes 0.1 to 0.5 weight% binder selected from Carrageenan or Sodium carboxy methyl Cellulose. It is further preferred that the composition includes 0.1 to 0.4 weight% Sodium carboxy methyl Cellulose (hereinafter referred to as SCMC), as the binder. SCMC is particularly preferred as it gives desired viscosity profile at relatively lower usage level. A combination of Carrageenan and SCMC is also particularly preferred. Synthetic polymers such as polyacrylates and carboxyvinyl polymers such as CARBOPOt™ may also be used. The preferred viscosity of the dentifrice composition is in the range of 160000 to 300000 cP, more preferably in the range of from 180000 to 300000 cP, and most preferably in the range of 180000 to 220000 cP. The viscosity is measured at 25 °C with a BROOKFIELD™ Viscometer using T-bar D-spindle at 5 rpm (revolutions per minute).

While the composition can be in the form of an opaque chalk/silica based toothpaste or a transparent gel, it is preferred that the dentifrice composition is a gel, as gel based dentifrices have higher consumer appeal and acceptance. The composition may also be a suitable combination of a paste and a gel; in the form of dual-compositions, available generally in core-&-sheath, deep-stripe and co-extruded formats. The balance of the dentifrice composition of the invention preferably includes conventional dentifrice ingredients. The final dentifrice composition should preferably be low water, which means that it preferably contains 5 to 10 weight% water, more preferably 7 weight% water; which limit is exclusive of any water present in the ingredients of the dentifrice.
The dentifrices of the present invention may contain further optional ingredients such as cosmetically acceptable carriers like starch, sucrose and alcohol systems. Small amounts of surfactants, such as anionic, nonionic and amphoteric surfactants may also be included. The compositions may further contain all the usual dentifrice ingredients. Thus, they may comprise particulate abrasive materials including agglomerated particulate abrasive materials such as silicas, aluminas, calcium carbonates (both natural and synthetic) , dicalciumphosphates, calcium pyrophosphates, hydroxyapatites, trimetaphosphates, and insoluble hexametaphosphates and so on, usually in amounts between 5 and 60 weight%.
Additional flavours such as peppermint and spearmint oils may also be included, as well as preservatives, opacifying

agents, colouring agents, pH-adjusting agents and sweetening agents, may also be included.
It is particularly preferred that the dentifrice composition contains an anti-bacterial agent selected from copper or stannous salts such as stannous pyrophosphate. Further examples of anti-bacterial agents, which may be included are quaternary ammonium compounds such as cetylpyridinium chloride; bis-biguanides such as chlorhexidine, chlorhexidine digluconate, hexetidine, octenidine, alexidine; TRICLOSAN™ and other halogenated bisphenolic compounds such as 2,2, methylenebis-{4-chloro-6-bromophenol).
It is preferred that the composition includes a 0.1 to 5 weight% Zinc salt, preferably 0.1 to 2 weight% and most preferably, the level of the Zinc salt is in the range of 0.1 to 0.5 weight%. Preferred zinc salts are zinc citrate, zinc lactate, zinc maleate, zinc salicylate, zinc gluconate and zinc ascorbate. Among these, Zinc sulphate, Zinc citrate and Zinc chloride are particularly preferred. However, the most preferred salt is Zinc sulphate. Mixtures of different zinc salts can be used. Excess amounts of zinc will lead to unacceptable taste and higher level of astringency and may cause problems of compatibility with other ingredients such-as e.g., precipitation of anionic polymers. Inclusion of Zinc salt surprisingly provides relatively superior freshness and fresh breath.
Polymeric compounds which can enhance the delivery of active ingredients such as anti-bacterial agents can also be included. Examples of such polymers are copolymers of

polyvinylmethylether with maleic anhydride and other similar delivery enhancing polymers.
Anti-caries agents such as sodium- and stannous fluoride, aminefluorides, monosodiumfluorophosphate, casein, plaque buffers such as urea, pyruvates, arginine, small peptides, and calcium glycerophosphate may also be included. It is particularly preferred that the anti-caries agent is Sodium fluoride. The addition of the fluoride containing agent will preferably be at such an amount to provide free fluoride ion at from 100 to 2000 ppm, preferably from 900 to 1500 ppm.
Other optional ingredients include vitamins such as Vitamin C, and plant extracts. Desensitising agents such as potassium tartarate, potassium citrate, potassium chloride, potassium bicarbonate, potassium oxalate, potassium nitrate, calcium phosphates as well as strontium salts, bleaching agents such as peroxy compounds e.g. sodium percarbonate, potassium peroxydiphosphate, effervescing systems such as sodium bicarbonate/citric acid systems, colour change systems, anti-bad breath ingredients may also be included. The composition may also include one or more of breath strips, sparkles, large silica particles, granules, beads, and flavour encapsulates for enhanced sensory benefits or for visual appeal.
Further, the composition may also include antioxidants. Preferred antioxidants for use in dentifrice compositions are those that are compatible with other components of the composition and are not hazardous to health. Preferred antioxidants include ascorbic acid, erythorbic acid, ascorbyl palmitate, thiodipropionic acid, calcium ascorbate,

dilauryldithiopropionate, gum guaiac, sodium ascorbate, BHT (Butylated Hydroxy Toulene), BHA (Butylated Hydroxy Anisole), and tocopherols. Mixtures and combinations of antioxidants can be used. If present, the antioxidant is added in a level effective to reduce or mitigate discoloration that would otherwise result from oxidation of the components of the dentifrice compositions. It is preferred that the levels range from about 0.01 to about 1 weight% of the antioxidant, based on the total weight of the dentifrice composition.
Buffers and salts to buffer the pH and ionic strength of the compositions may also be included.
The heating effect is linked to the efficacy of the product by the consumers. In addition, the dual sensations of heat followed by cold, is a unique consumer desirable attribute of the compositions.
The invention will now be explained in greater detail with the help of the following non-limiting examples.
EXAMPLES
EXAMPLE-1
PEG v/s Glycerine-Sorbitol as warming agents - Consumer Panel test
In this experiment, the degree of warming provided by various compositions {containing PEG as warming agent) was tested against a composition having a combination of

Glycerine and Sorbitol as the warming agents in a panel test involving 150 consumer panellists. Table-1 below gives the formulations of all compositions which were tested.
Table-1

Composition Code
Ingredient/ weight% A B C D
Glycerine 8.0 10.0 15.0 30.0
Sorbitol - - - 32.0
SCMC 0.4 0.4 0.4 0.6
Water 7.0 7.0 7.0 13.5
PEG-600 57.8 55.8 50.0 -
Sweetener 0.3 0.3 0.3 0.3
Sodium fluoride 0.2 0.2 0.2 0.2
Zinc sulphate 0.2 0.2 0.2 0.2
Hydrated silica 23.0 23.0 23.0 11.0
PEG 1500 - - - 0.6
Sodium Lauryl Sulphate 2.0 2.0 2.0 2.0
Colour, flavour and other minors to 100 100 100 100
% of panellists who liked the warming intensity 93 97 92 60
The compositions were made in the manner well-known in the art. The panellists were asked to brush their teeth with the dentifrice compositions and to comment upon whether they liked the warming intensity or not. Table-1 also gives the percentage of panellists who said they did like the warming intensity of each composition.
The results indicate that over 90 % of the consumers liked the warming intensity of dentifrice compositions containing Polyethyleneglycol-600 as the warming agent at varying levels, whereas only 60 % panellists liked the warming intensity of dentifrice composition which had a combination

of Glycerine and Sorbitol. The results indicate that PEG is the preferred warming agent.
EXAMPLE-2
Effect of N-substituted p-menthane carboxamide on the bitterness of PEG
A gel-based dentifrice within the scope of the present invention was made. The dentifrice in accordance with the invention included 56 weight% PEG-600 and N-substituted, p-menthane carboxamide. In addition a comparative gel-based dentifrice containing 56 weight% PEG-600 and a standard coolant was also made by a manner well-known in the art.
The Table-2 below gives detailed formulations of the composition (E) within the scope of the invention, and the comparative composition (F).

Table-2

Ingredient/weight % Composition E Comparative Composition F
PEG-600 56.0 56.0
Glycerine 10.0 10.0
SCMC 0.4 0.4
Sweetener 0.2 0.2
Sodium fluoride 0.2 0.2
Zinc Sulphate 0.2 0.2
Water 7.0 7.0
Hydrated silica 23.0 23.0
Sodium Lauryl Sulphate 2.0 2.0
Flavour 1.0
(includes 0.05 N-
<4-
cyanomethylphenyl) p-methane carboxamide) 1.0
(standard flavour, Menthol)
Colorants, pigments and other minors to 100' 100
EXAMPLE-3
Method for preparation of the composition-E of Table-2
The method involved two stages:
Stage-1: Pre-hydration of binder SCMC
Glycerine and SCMC were accurately weighed. SCMC was then gradually added to Glycerine under stirring at room temperature. This addition was continued while ensuring that no lumps were formed, and the powder completely dispersed into the liquid phase giving a clear viscous dispersion. Stirring was discontinued after the addition of SCMC was complete. The resultant.clear dispersion was checked for the presence of any un-dissolved matter before proceeding further. This premix was added to pre-weighed water under

stirring, until the addition was complete and the mixture was completely homogenized. This pre-hydrated mix was used for preparation of gel-based toothpaste as per the procedure in stage-2. Pre-hydration stage takes about 25-30 minutes.
Staqe-2: Preparation of the dentifrice composition
PEG-600 was charged into a FRYMA™ Mixer. To this mixer, Sodium fluoride and Zinc sulphate were added. The scraper of the mixer was started and the contents of the mixer were under vacuum for about 5-10 minutes. Next, part of hydrated silica (10 g) was added and the contents were mixed for further 10 minutes. To this mixture, the pre-hydrated binder mix as prepared above was added while maintaining the mixer under vacuum for about 5 minutes. Next the remaining hydrated silica was added and the mixture was further mixed for about 5 minutes. Finally the colorant, sweetener, pigment, flavour, other minors and Sodium Lauryl Sulphate were added to the mixer, and the mixture was further mixed for another 10 minutes. At the end, the mixture was cooled below 38 °C and the flavour was added. The preparation was further mixed under vacuum for about 10 minutes to obtain the final dentifrice composition in gel form.

EXAMPLE-4
Consumer panel test for bitterness of composition-E of Table-2
In a study with 140 consumer panellists, the Composition E and Comparative Composition F of Table-2 were tested for the effect of N-substituted p-menthane carboxamide on the bitterness of PEG, among other important product attributes. Each panellist was asked to brush the teeth with both the compositions, and to answer the following questions.
Questions:
1. Does this toothpaste have the right level of warming?
2. Does the toothpaste give you right duration of warming?
3. Is the flavour impact right?
4. Is the flavour taste right?
5. Which toothpaste is less bitter?
The results are presented in table-3 below.
Table-3

Question number % of consumer panellists saying yes in favour of Composition E
1 97
2 94
3 91
4 94
5 95 % said Composition E was less bitter, and had better flavour appreciation than Comparative Composition F
Thus, it can be seen that most of the consumers said that the Composition E within the scope of the invention had significantly lower bitterness, apart from right flavour

impact, flavour taste, and right duration and level of warming.
EXAMPLE-5
Consumer Panel test of Compositions E and F
In a separate consumer panel test involving BOO consumers, the relative freshness feeling provided by Composition-E and Comparative Composition-F of Table-2 were evaluated. The panellists were split into 2 groups of 400 panellists each. One group tested Composition-E and the other tested Comparative Composition-F. Each panellist was asked to brush twice a day with the compositions for one week. They were then asked to rate the composition on the eight parameters given in Table-4 below on a scale of 1 to 5 (low to high)
The results of this panel test in terms of average panellist score at 95% confidence are also compiled and presented in Table-4 below.
Table-4

Parameter Comp-E Comp-F
Gives long-lasting freshness for hours and hours 2.72 2.54
Gives a long-lasting cooling sensation post brushing 3.02 2.8
Leaves a fresh feeling in the mouth after brushing 3.36 3.11
Gives a warming sensation of toothpaste at the start of brushing 3.87 3.84
Freshness Likeability 3.19 2.99
Long Lasting Freshness 2.06 1.87
Satisfaction On Long Lasting Freshness 2.99 2.77
Comparative Superior Freshness 2.57 2.34
Note: In the above table, "Comp" means Composition.

The data in the above table indicates that Composition-E was superior to Comparative Composition-F in the above parameters.
EXAMPLE-6
PEG-400 and PEG monomethyl ether as the warming agents
Example-1 shows that compositions which included PEG-600 showed an appreciable warming effect. In another experiment, two gel dentifrice compositions; one containing PEG-400 and the other containing PEG mono methyl ether (molecular mass 550 g/mol) were made as per procedure given in Example-3. One gram of the composition at 22.7 °C was mixed with 1 g water at 37 °C to find out the increase in temperature. Details of the compositions and the increase in temperature provided by both compositions are given in Table-5 below.

Table-5

Ingredient/weight% Composition 6 Composition H
PEG-400 56.0 —
PEG mono methyl ether-550 _ 56.0
Glycerine 10.0 10.0
SCMC 0.4 0.4
Sweetener 0.2 0.2
Sodium fluoride 0.2 0.2
Zinc Sulphate 0.2 0.2
Water 7.0 7.0
Hydrated silica 23.0 23.0
Sodium Lauryl Sulphate 2.0 2.0
Flavour (includes 0.05
weight%
N-(4-cyanomethylphenyl)
p-methane carboxamide) 1.0 1.0
Colorants, pigments and other minors to 100 100
Rise in temperature 2 to 3 °C 2 to 3 °C
Thus it is clear from the results above that compositions including PEG-400 or PEG mono methyl ether-550 also showed appreciable increase in temperature.
EXAMPLE-7
Effect of the binder on viscosity of the composition
In another set of experiments, the effect of various binders on the viscosity of the composition was studied. Three different binders and a combination of two binders were tried. The Composition-E of Table-2 was tested against three other compositions I, J and K. The formulation of compositions I, J and K was similar to that of composition-E, except for the replacement of the binder. In case of Composition-K, an equivalent amount of water was reduced, as

the amount of binder in Composition K was 0.5 weight% as against 0.4 weight% in Composition-E. The Table-6 below highlights the differences in the formulations. Viscosity of all the compositions was measured after 14 days storage at 25 °C and 50% Relative humidity. The viscosity was measured at 25 °C with a BROOKFIELD™ Viscometer using T-bar D-spindle at 5 rpm. This data is also included in Table-6 below.
Table-6

Composition Binder Weight% Viscosity/(cP)
E (of Table-2) SCMC 0.40 218000
I Carrageenan 0.40 161000
J Xanthan gum 0.40 69000
K Carrageenan and SCMC 0.50
(0-25
each) weight% 270000
Thus it can be seen that Composition-E, Composition-I and Composition-K showed the desired viscosity (160000 to 300000 cP) which provides for relatively high physical stability, which is essential for extrusion of the dentifrice composition from a tube. On the other hand Composition-J showed value outside the above range.
It will be appreciated that the illustrated examples provide dentifrice compositions that include relatively high levels of Polyethyleneglycol, or a derivative thereof; while still exhibiting relatively lower bitterness.
It should be understood that the specific forms of the invention herein illustrated and described are intended to be representative only as certain changes may be made

therein without departing from the clear teachings of the disclosure.
Although the invention has been described with reference to specific embodiments, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

WE CLAIM:
1. A dentifrice composition comprising:
(i) 40 to 60 weight% Polyethyleneglycol or a
derivative thereof; and, (ii) 0.01 to 2 weight% N-Substituted p-menthane
carboxamide.
2. A dentifrice composition as claimed in claim 1 wherein
said N-subsituted p-menthane carboxamide is
selected from N-(4-cyanomethylphenyl)p-
menthanecarboxamide, N-(4-sulfamoylphenyl)p-
menthanecarboxamide, N-(4-cyanophenyl}p-menthanecarboxamide, N-(4-acetylphenyl)p-menthanecarboxamide, N-(4-hydroxymethylphenyl)p-menthanecarboxamide or N-(3-hydroxy-4-methoxyphenyl) p-menthanecarboxamide.
3. A dentifrice composition as claimed in claim 1 or 2 wherein the molecular mass of said Polyethylene glycol is in the range of 200 to 600 g/mol.
4. A dentifrice composition as claimed in any one of the preceding claims wherein said Polyethyleneglycol or the derivative thereof is in the range of 50 to 55 weight%.
5. A dentifrice composition as claimed in any one of the preceding claims comprising 5 to 10 weight% water.
6. A dentifrice composition as claimed in any one of the preceding claims comprising 8 to 15 weight% humectant

selected from glycerine, sorbitol or propylene glycol.
7. A dentifrice composition as claimed in any one of the preceding claims comprising 0.1 to 0.5 weight% binder selected from Carrageenan or Sodium carboxy methyl Cellulose.
8. A dentifrice composition as claimed in any one of the preceding claims wherein viscosity of said composition is in the range of 160000 to 300000 cP.
9. A dentifrice composition as claimed in any one of the preceding claims wherein said derivative of Polyethyleneglycol is Polyethyleneglycol mono methyl ether.
10. A dentifrice composition as claimed in any one of the preceding claims comprising 0.1 wt% to 5 weight% Zinc salt.