HIGH SALT TOOTHPASTE WITH STABLE VISCOSITY

FieU

[0001] The present invention relates to oral care compositions that contain high levels of salt and a novel carrageenan-based binder, and that have very stable viscosity and excellent striping properties.

B ckground

[0002] Gum disease affects a significant number of people worldwide, and is a leading cause of tooth loss. Gum disease usually be gins with gingivitis, in which bacteria in dental plaque build up, causing the gums to become inflamed. Dental plaque is a soft deposit which forms on teeth and is comprised of an accumulation of bacteria and bacterial by-products. Plaque adheres tenaciously at the points of irregularity or dis ontinuity, e.g., on rough calculus surfaces, at the gum line and the tike . A wide variety of antibacterial agents have been suggested in the art to retard plaque formation. For xample, halogenated hydroxydi phenyl ether compounds such as triclosan are well known to the art for their antibacterial activity and have bee used in oral compositions to counter plaque formation by bacterial accumulation in the oral cavity. However, while many people would prefer to use natural products such sodium chloride and other ratural salts to provide antibacterial activity, the presence of high lev ls of salt poses special challenges in formulating a toothpaste that has stable viscosity and good striping characteristics. Thus there is a n d for novel toothpaste formulations possessing these characteristics . Thus invention is dire cte d to the se , as well, as othe r, important e nds.

Summary

[0003] Unless otherwise indicated, the terms 'Ύ " or ^Li percent" when used in connection with an ingredient of the toothpaste compositions of the invention is intended to re fer to the perc ent by weight of the indie ate d ingredient in the toothpaste c omposition.

[0004] In some embodiments, the present invention provides a toothpaste composition having high salt concentration and a binder system that provides a stable viscosity over an extended period of time. In some embodiments, the toothpaste composition contains at least 5% sodium chloride by weight. In some further embodiments, the toothpaste contains from 5% to 15% sodium chloride, for example from S% to 12% sodium chloride . In some embodiments, the toothpaste contains about 10% sodium chloride .

[0005] In some embodiments, the binder syste m include s from carrage nan in an amount of from 0.5% to 1.5%, for example 0.6%, 0.7%, 0.8% 0.9%, 1%, 1 .1%, 1.2%, 1.3% or 1 .4% by weight of the toothpaste composition. In some embodiments, the binder system optionally also contains one or more carboxymethylcellulose s, in an amount of from 0.1% to 1% by weight of the toothpaste composition; for example from 0.1% to 0.5%; 0.1% to 0.4%; 0.1% to 0.2%; or about 0.3% by weight of the toothpaste composition. In some embodiments, the carboxyn^mylceUulose is or comprises CMC 2000s.

[0006] In further enitoodiments, the toothpaste further includes one or more humectants. In some embodiments, the humectant is sorbitol, which is present in an amount of from 55% to 70%; or 60% to 66%; or about 63%.

[0007] In some embodiments, the carrageenan-binder toothpaste further includes one or more disp rsants. In some embodiments, the dispersant is a polyethylene gly ol, for example polyethylene glycol 600. In some embodiments, the poly thylene glycol is present in an amount of from 0.5% to 2%, for example 1%.

[0008] In some embodiments, the carrageenan-binder toothpaste further includes a thickener, for example thickener silica, in an amount of from 1% to 6%, or from 2% to 4%, for example 3% to 5%, for example 3%, 4% or 5%.

[0009] In some embodiments, the carrageenan-binder toothpaste further includes an abrasive, whic is preferably an abrasive thick ner, in an amount of from 5% to 10%. In some embodim nts, the abrasive thickener is silica, in an amount of 5%, 6%, 7%, 8%, 9% or 10%.

[0010] In some embodiments, the toothpaste further includes one or more detergents or surfactants. In some embodiments, the toothpaste further includes sodium lauryl sulfate and a poloxamer, for example and without limitation poloxamer 407. In some embodime ts, the sodium lauryl sulfate is present in an amount of from 1% to 3% by weight of the toothpaste composition, for example about 2%, and poloxamer 407 is prese t in an amount of from 0.5% to 2%, for example about 1%. [0011] In some embodiments, the toothpaste further includes a fluoride source, for example and without limitation monofluorophosphate (MFP), sodium fluoride, or stannous fluoride. In some embodiments, the fluoride source is sodium fluoride, whic is present in an amount of from 0.15% to 0.5%, or from 0.2% to 0.3%.

[0012] In some embodiments, the toothpaste further includes one or more adjuvants selected form sweetening agents, flavoring agents and coloring agents. In some e mbodiments, the toothpaste contains flavoring in an amount of up to 3% by weight of the toothpaste composition; for example from 0.5% to 3.0; 0.8% to 1 .6%; or about 1.2%. In some furth r embodiments, the toothpaste contains one or more sweetening a ents in an amount of up to 0.5% by weight of the toothpaste composition; for example up to 0.3% ; or from 0.1 % to 0.2% .

[0013] In some embodiments, the toothpaste includes from 8% to 12% sodium chloride, or 10% sodium chloride; and from 0.6% to 1.1% carrageenan, or 0.7%, 0.8%, 0.9%, or 1.0% carrageenan and, optionally, carbo-iymethylcellulose, pr ferably CMC 2000s, in an amount of from 0.1% to 1%, or from 0.1% to 0.5%, or from 0.1% to 0.4%, or from 0.1 % to 0.2%, or about 0.3% .

[0014] In some embodiments, the toothpaste includes from 8% to 12% sodium chloride; from 0.6% to 1 .1% carrageenan; optionally from 0.1% to 0.5% CMC 2000s; from 55% to 70% sorbitol; and from 0.5% to 2% polyethylene glycol 600.

[0015] In some embodiments, the toothpaste includes from 8% to 12% sodium chloride; from 0.6% to 1 .1% carrageenan; optionally, from 0.1% to 0.5% CMC 2000s; from 60% to 65% sorbitol; and from 0.5% to 2% polyethylene glycol 600.

[0016] In some embodiments, the toothpaste includes from 5% to 10% abrasive thickener silica; from 2% to 6% thickener silica; from 1% to 3% sodium lauryi sulfate ; from 0.5% to 2% poloxamer 407; and from 0.1% to 0.5% sodium fluoride .

[0017] In some embodiments, the toothpaste includes from 5% to 15% sodium chloride ; a binder system omprising from 0.6% to 1.1% carrageenan, and, optionally, from 0.1% to 0.5% carboxymemylcellulose; humectant in an amount of from 60% to 65%; tiuckener silica in an amount of from 2% to 6%; abrasive thickener in an amount of from 5% to 10%; and a fluoride source . In some such embodiments, the abrasive thickerer is silica; the humectant is sorbitol; and the fluoride source is sodium fluoride. In some such embodiments, the toothpaste further includes one or more surfactants or detergents, preferably selected from sodium lauryi sulfate, poloxamer 407 and one or more dispersants, preferably a polyethylene glycol such as polyethylene glycol 600. In some such embodiments, sodium lauryi sulfate is present in an amount of from 1% to 3%; polo-iamer 407 or is present in an amount of from 0.5% to 2%; polyethylene glycol 600 is present in an amount of from 0.5% to 2%; and sodium fluoride is present in an amount of from 0.1 % to 0.5% .

[0018] In some embodiments, the toothpaste includes S% to 12% sodium chloride; 0.6% to 1 .1% c rrageenan; optionally 0.1% to 0.5% CIvE2000s; 60% to 65% sorbitol (70 wt% aqueous solution); 0.5% to 1.5% polyethylene glycol 600; 5% to 10% abrasive thickener silica; 1% to 3% sodium lauryi sulfate; 0.5% to 2% polo-iamer, e.g., Pluracare F127NF; 2% to 6% thickener silica; and 0.15% to 0.5% sodium fluoride.

[0019] In some further embodiments, the invention provides a toothpaste comprising: sodium chloride in an amount of from 6% to 12%; a binder system comprising from 0.5% to 1 .5% carrageenan, and, optionally, from 0.1% to 0.5% carbo-iymethylce llulose , an abrasive ; one or more detergents; one or more dispersants; and a fluoride source; wherein the toothpaste is striped, translucent, and contains more sodium c hloride by we ight than abrasive .

[0020] In some further embodiments, the invention provides a method for stabilizing a toothpaste having high salt concentration, comprising mixing the salt with a binder system, wherein the binder system comprises from 0.5% to 1 .5% carrageenan, and, optionally, from 0.1% to 0.5% carboxymemylcellulose.

[0021] In some further embodiments, the invention provides the use of carrageenan to stabilize viscosity in a high-salt toothpaste or in the manufacture of a toothpaste according to the present invention.

Brief Descry tion of the Drawings

[0022] Fig. 1 shows the results of the Thixotropic Test described in Example 2. Detailed Description

[0023] It has been discovered in accordance with the present invention that high levels of sail, for example sodium c loride, can be formulated with a binder system that includes carrageenan as described herein to provide a toothpaste that has a stable viscosity over an exte ded period of time, excellent striping properties, translucence, and effective antibacterial properties.

[0024] The present invention provides toothpaste compositions that contain at least 5% sodium chloride . In some mbodiments, the toothpaste compositions of the invention contain from 5% to 15% sodium chloride, with from 8% to 12% sodium chloride being preferred. In some embodiments, the toothpaste contains about 10% sodium chloride. While not wishing to be bound by any theory, the inclusion of high levels of sodium chloride in accordance with the invention is believed to impart antibacterial properties to the compositions, providing benefits in terms of both rrininuzing bacterial growth during storage and antiba erial effi y during use.

[0025] The binder system of the toothpaste compositions of the present invention contain primarily, or consist of, carrageenan. Carrageenans are known to be linear sulfated polysaccharides that are extracted from red seawe ds. For example, gelatinous extracts of the Chondrus crispuz (Irish Ivbss) seaweed are known to be useful as food additives. There are three main varieties of carrageenan, d signated kappa, iota and lambda, which differ in their de ree of sulfation. While any of the kappa, iota or lambda carrageenans are suitable for use with the present invention, iota-carrageenan is preferred. In some embodiments, the binder system includes carrage nan in an amount of from 0.5% to 1 .5%, for example 0.6%, 0.7%, 0.8% 0.9%, 1%, 1.1%, 1 .2%, 1.3% or 1 .4% carrageenan by weigh by weight of the toothpaste composition.

[0026] In some en^odiments, the toothpaste compositions of the invention further include one or more binding and or thic ning agents. Binding agents may include polymers include polyethylene glycols, polysaccharides (e .g., cellulose derivatives, for xample carboxym thyl cellulose, or polysaccharide gums, for example xanthan gum or carrageenan gum). Acidic polymers, for example polyacrylate gels, may be provided in the form of their free acids or partially or fully neutralized water soluble alkali metal (e.g., potassium and sodium) or ammoriium salts; and include synthetic anionic polymeric polycarboxylates, such as 1 :4 to 4: 1 copolymers of maleic arihy ride or acid with another polymerizable ethylenically unsaturated monomer, pr ferably methyl vinyl ether/male ic ar-hydride having a molecular weight (MW.) of about 30,000 to about 1,000,000, most preferably about 300,000 to about 800,000. In some embodiments, the binder system contains carrageenan as described above, and one or more binding agents derived from cellulose, preferably a cellulose ether, for example carbo-iymethylcellulose (CMC), e.g. having a medium to high degree of polymerisation, e .g. 1000 to 3000, for example about 2000, e.g., in sodium salt form, e .g., CMC 2000s, in an amount effective to provide the desired viscosity and stability, e.g., from 0.1% to 0.5%, or from 0.1% to 0.4%, or from 0.1% to 0.2%, or about 0.3% by weight of the toothpaste composition.

[0027] The toothpaste compositions of the invention further include humectant. ie . one or more humectants. Examples of suitable humectants include polyhydric alcohols (polyols) such as propylene glycol, glyc rin, sorbitol, xylitol or low molecular weight polyethylene glycols (PEGs). In various embodiments, humectants can prevent hardening of paste or gel compositions upon exposure to air, and also function as sweeteners. In some embodiments, the humectant system consists primarily or solely of sorbitol, e.g., in an amount of from 55% to 70%; or 60% to ό ^" ό ^" %; or about 63% by weight of the toothpaste composition. However, the presence of other humectants still providing satisfactory toothpaste properties is also contemplated.

[0028] In some embodiments, the toothpaste further includes one or more dispersants. In some e mbodiments, the dispersant is a alkylene glycol such as polyethylene glycol, for example polyethylene glycol 600. In some embodiments, the polyethyl ne gly ol is present in an amount of from 0.5% to 2%, for example 1%.

[0029] In some embodiments, the toothpaste compositions of the invention further in lude one or more thickeners (i.e., thickening agents), which aid in obtaining the proper viscosity of the composition. Generally, the thickener is present in the composition in an amount of from 1% to 6%. Examples of like ing agents include, without limitation, the binding agents described above, which also nidify viscosity, for example carboxyvinyl polymers, cellulosic polymers such as hydroxy myl eUulose, carboxymethylce llulose (carmellose) and salts thereof (e.g., carmellose sodium), natural gums such as karaya, xanthan, gum arabic and tragacanth, colloidal magnesium aluminum silicate, colloidal silica, and mixtures thereof. One preferred tluckener is thicken r silica, in an amount of from 1% to 6 ^" %, or from 2% to 4%, for example 2%, 3% or 4%.

[0030] In some preferred embodiments, the toothpaste includes from 8% to 12% sodium chloride, or 10% sodium chloride; and from 0.o ^" % to 1 .1% carrageenan, or 0.7%, 0.8%, 0.9%, or 1 .0% carrageenan and, optionally, carboxymemylceUulose, preferably CMC 2000s, in an amount of from 0.1% to 1%, or from 0.1% to 0.5%, or from 0.1% to 0.4%, or from 0.1% to 0.2%, or about 0.3%.

[0031] The toothpaste compositions further omprise an abrasive, e.g. selected from abrasive silica and/or calcium salts, e .g. calcium carbonate and/or a calcium phosphate abrasive, e.g., trie ale ium phosphate (CajfPO+Jj), hydroxyapatite (Caio(FO+)i(OH)j), or dicalcium phosphate dihydrate (CaHPGt ^■ 2HjO, also sometimes referred to herein as DiCal) or calcium pyrophosphate . In a particular embodiment, the abrasive in ludes or is compos d of silica, for example abrasive thickener silica in an amount of from 5% to 10%, or 5%, 6%, 7%, 8% 9% or 10% by weight of the toothpaste composition.

[0032] The toothpaste compositions of the invention can further include one or more detergents or surfactants. Surfactants useful for the pres t invention include, without limitation: anionic, nonionic, and amphoteric surfactants. Surfactants maybe used, for example, to provide enhanced stability of the formulation, to help in cleaning the oral cavity surfaces through detergency, and to increase foaming of the composition upon agitation, e.g., during brushing. Suitable anionic surfactants include, for example, water-soluble salts of C$.jo alkyl sulfates, sulfonated monoglyce rides of O^a fatty acids, sarcosinates and taurates; for example sodium lauryl sulfate, sodium coconut monoglyceride sulfonate, sodium lauryl sarcosinate, sodium lauryl iso lhionate, sodium laurethcarboxylate and sodium dodecylbensenesulfonate, and mixtures thereof. Suitable nonionic surfactants include, for example, poloxamers, polyoxyethyiene sorbitan esters, fatty alcohol ethoxylates, alkylphenol ethoxylates, tertiary amine oxides, tertiary plrosphine oxides, dialkyl sulfoxides, and mixtures thereof. In one embodiment, the toothpaste comprises sodium lauryl sulfate, for example in an amount of from 1% to 3%, or about 2%. The toothpaste may also or alternatively contain one or more nonpolar surfactants, for example polymers and co-polymers of ethylene glycol and propylene glycol, e.g.. poloxamers, i.e., nonionic triblock copolymers composed of a central hydrophobic chain of polyoxypropylene (polypropylene oxide)) flanked by two hydrophilic chains of polyoxyethylene (poly(ethylene oxide)). The approximate lengths of the two PEG blocks is, in some embodiments, an average of about 50-150 repeat units, e.g., about 100 repeat units while the approximate length of the propylene gycol block is an average of about 25-75 repeat unties, e.g., about 50-o ^~ 0 repeat units. In one embodiment the poloxamer is poloxamer 407, also known by the BASF trade name Pluronic F1 7, e.g., in an amount of from 0.5% to 2%, for example about 1%. For example, in certain embodiments, the toothpaste compositions of the invention may contain both sodium lauryl sulfate and a poloxamer such as poloxamer 407. In some embodiments, the sodium lauryl sulfate is present in an amount of from 1% to 2%, for example about 2%, and the poloxamer such as poloxamer 407 is present in an amount of from 0.5% to 2%, for example about 1%, by weight of the toothpaste composition.

[0033] The toothpaste compositions of the present invention may also contain a fluonde source - i.e., a fluoride -containing compound leaving a beneficial effect on the care and hygiene of the oral cavity, e .g. diminution of enamel solubility in acid and protection of the teeth against decay. Examples of suitable fluoride sources include sodium fluoride, stannous fluoride, potassium fluoride, potassium stannous fluoride (SNFZ-KF). potassium fluorozirconate, sodium h xafluorostannate, stannous chlorfluoride, and sodium monofluorophosphate (MFP). Where present the fluoride source would provide fluoride ion in amounts sufficient to supply about 25 ppm to about 25,000 ppm of fluoride ions, generally at least about 500 ppm, e.g., about 500 to about 2000 ppm, e.g., about 1000 to about 1600 ppm, e.g., about 1450 ppm. The appropriate level of fluoride will depend on the particular application. A toothpaste for general consumer use would typically have about 1000 to about 1500 ppm, with pediatric toothpaste having somewhat less. A dentifrice or coating for professional application could have as much as about 5,000 or even about 25,000 ppm fluoride. The amount by weight of these materials, which dissociate or release fluoride or fluorme-containing ions, will depend on the molecular weight of the counterion as well as on the particular application, but suitably ma be present in an effective but non- toxic amount usually within the range of 0.1 to 2% by weight. In some embodiments, a fluoride source selected from sodium fluoride, stannous fluoride, sodium monofluorophosphate and mixtures thereof, is used, for example the toothpaste of the invention may comprise an effective amount of sodium monofluorophosphate . In some embodiments, the fluoride source is sodium fluoride, which is present in an amount of from 0.15% to 0.5%, or from 0.2% to 0.3% by weight of the toothpaste composition.

[0034] As will be evide t to one of skill in the art, some omponents of the invention may perform multiple functions, and the identification of a compound as having one function herein is not meant to exclude its use for other functions in a parti ular composition. For example, a compound such as carboxymethylcellulose may act as a binder, but also has humectant and i ckening properties, or a compound such as a Poloxamer, while identified above as a nonionic surfactant also has humectant and thickening properti s, and a compound such as polyethyl ne glycol o ^" 00, while identified above as a dispersant, also may function as a diluent and/or humectant.

[0035] It is also understood that compounds in formulation may naturally read, disassociate, and/or form comple es with one another. Accordingly, certain ingredi nts maybe formed 5itu (for example, it is understood that sodium chloride maybe formed by reacting sodium hydroxide with hydro hloric acid), and also may in formulation exist in different forms (for example, to the extent the sodium chloride is dissolved, it will naturally disassociate into separate sodium and c hloride ions, as opposed to a solid salt). As is usual in the art, the compositions of the invention are described in terms of exemplary formulation ingredients, without intending to exclude combinations of other ingredients that result in the same final compositions, or to exclude the natural reaction products of the described ingredient combinations.

[0036] In some embodiments described above, the toothpaste compositions of the mvention can further include one or more sweetening agents, flavoring agents and coloring agents. Any suitable flavoring or sweetening material may be employed. Examples of suitable flavoring constituents include flavoring oils, e.g. oil of spearmint, peppermint, wintergr n, clove, sage, eucalyptus, marjoram, cinnamon, lemon, and orange, and methyl salicylate . Suitable sweetening agents include sucrose, lactose, maltose, xylitol, sodium cyclamate, perillartine, AMP (aspartyl phenyl danine methyl ester), saccharine and the lite . Suitably, flavor and sweetening agents may each or together comprise from about 0.1% to 5% more of the oral care composition. In some embodiments, the toothpaste compositions of the invention include one or more tlavoring agents in an amount of from about 0.5% to about 3.0%; about 0.8% to about l .o ^" %; or about 1 .2%. In some further embodiments, the toothpaste contains one or more sweetening agents in an amount of up to 0.5% by weight of the toothpaste composition; for example up to 0.3%; or from .1% to 0.2%.

[0037] Various other materials may be incorporated in the oral preparations of this invention such as whitening agents, including urea peroxide, calcium peroxide, titanium dioxide, hydrogen peroxide, complexes of polyvmylpymlidone (EVP) and hydrogen peroxide, preservatives, vitamins such as vitamin Bo ^" , B12, E and K, silicones, chlorophyll compounds, potassium salts for the treatment of dental hypersensitvity such as potassium nitrate as well as anti tartar agents such as sodium tri polyphosphate and di- and tetra-alkali metal pyrophosphate salts such as di- and tetrasodium pyrophosphate . These agents, when present, are incorporated in the compositions of the present invention in amounts which do not substantially adversely affect the properties and chara teristics desired.

[0030] In general, each of the foregoing adjuvants maybe typically incorporated in the instant toothpastes in amounts up to 5% provided they do not adversely affect the stability and cleaning properties of the non-bleeding striped dentifrice of present invention.

[0039] In some embodiments, the canageenan-binder toothpaste includes from 5% to 15% sodium chloride; a binder system comprising from 0.6 ^" % to 1.1% carrageenan, and, optionally, from 0.1% to 0.5% carboxymethylcellulose; Ihickener silica in an amount of from 2% to o ^" %; abrasive thickener in an amount of from 5% to 10%; humectant in an amount of from o ^" 0% to o ^" 5%; and a fluoride source . In some such embodiments, the abrasive Ihickener is silica; the humectant is sorbitol; and the fluoride source is sodium fluoride. In some such en odiments, the toothpaste further includes one or more surfactants or detergents, preferably selected from sodium lauryl sulfate, poloxamer 407 and Pluracare F1 7 F, and one or more dispersants, preferably a polyethylene glycol such as polyethylene glycol 600. In some such en^odrments, sodium kuryl sulfate is present in an amount of from 1 % to 3% ; Polo-iamer 407 or Pluracare F127NF is pre sent in an amount of from 0.5% to 2%; polyethylene glycol 600 is pr sent in an amount of from 0.5% to 2%; and sodium fluoride is present in an amount of from 0.1% to 0.5%.

[0040] In some embodiments, the toothpaste includes 8% to 12% sodium chloride; 0.6% to 1 .1% carrageenan; optionally 0.1% to 0.5% CIvE2000s; 60% to 65% sorbitol (70 wt% aqueous solution); 0.5% to 1.5% polyethylene glycol 600; 5% to 10% abrasive thickener silica; 1% to 3% sodium lauryl sulfate ; 0.5% to 2% Pluracare F127NF; 2% to 6% thicke er silica; and 0.15% to 0.5% sodium fluoride .

[0041] In some further embodiments, the invention provides a toothpaste comprising: sodium chloride in an amount of from 6% to 12%; a binder system comprising from 0.5% to 1 .5% carrageenan, and, optionally, from 0.1% to 0.5% carboxymethylce llulose ; an abrasive ; one or more detergents; one or more dispersants; and a fluoride source; wherein the toothpaste is sniped, translucent, and contains more sodium c hloride by we ight than abrasive .

[0042] In some further embodiments, the invention provides a method for stabilizing a toothpaste living high salt concentration, comprising mixing the salt with a binder system, wherein the binder system comprises from 0.5% to 1 .5% carragee an, and, optionally, from 0.1% to 0.5% carboxymethylcellulose.

[0043] The invention thus provides, in one entoodiment. a toothpaste comprising at least 5% sodium chloride; from 5% to 15% sodium chloride; from 8% to 12% sodium chloride; or about 10% sodium chloride (Composition 1), together with a binder and humectant, for example :

1.1 . Composition 1, wherein the binder system comprises a carrageenan, in an amount of from 0.5% to 1.5%, or 0.6%, 0.7%, 0.8% 0.9%, 1%, 1 .1%, 1 .2%, 1.3% or 1.4% by weight of the toothpaste composition.

1.2. Any foregoing composition wherein the binder system comprises a cellulose derivative, e.g., carboxymethylcellulose (CMC), e.g. having a medium to high degree of polymerization, e.g. 1000 to 3000, for example about 2000, e.g., in sodium salt form, e.g., CMC 2000s, in an amount effective to provide the desired viscosity and stability, e.g., from 0.1% to 0.5%, or from 0.1% to 0.4%, or from 0.1% to 0.2%, or about 0.3% by weight of the toothpaste composition.

1.3. Any foregoing composition wherein the humectant comprises a polyol, e.g.. sorbitol, e.g., sorbitol in an amount of from 55% to 70%; or 60% to ό ^" ό ^" %; or about 63% by weight of the toothpaste composition.

1.4. Any foregoing composition further comprising one or more dispersants, e.g., polyethylene glycol, for example polyethylene glycol 600, in an amount of from 0.5% to 2%, or about 1% by weight of the toothpaste composition.

1.5. Any foregoing composition further comprising one or more thicke ers, e .g., thickener silica, in an amount of from 1% to 6%, or from 2% to 4%, or 2%, 3% or 4% by weight of the toothpaste composition.

1.6. Any foregoing composition further comprising one or more abrasives, which is preferably an abrasive thickener, e.g., abrasive thickener silica, in an amount of from 5% to 10%, or 5%, 6%, 7%, 8% 9% or 10% by weight of the toothpaste composition.

1.7. Any foregoing composition further comprising one or more anionic detergents or surfactants, e .g., sodium lauryl sulfate, in an amount of from 1% to 3%, or about 2%; and one or more nonionic surfactants, e.g., a polo-iamer, e.g., poloxamer 407, in an amount of from 0.5% to 2%; or about 1%.

1.8. Any foregoing composition further comprising an effective amount of a fluoride ion source ; e.g., sodium fluoride, in an amount of from 0.15% to 0.5%, or from 0.2% to 0.3%.

1.9. Any foregoing composition comprising:

from 8% to 12% sodium chloride;

from 0.6% to 1.1% carrageenan;

optionally, from 0.1% to 0.5% CMC 2000s;

from 55% to 70% sorbitol;

from 0.5% to 2% polyethylene glycol 600;

from 5% to 10% abrasive thickener silica;

from 2% to 6% thickener silica;

from 1% to 3% sodium lauryl sulfate;

from 0.5% to 2% poloxamer 407; and

from 0.1% to 0.5% sodium fluoride. 1.10. The toothpaste of any foregoing compositions, comprising from 55% to 70% sorbitol.

1.1 1 . The toothpaste of any foregoing ompositions, further comprising one or more adjuvants selected from sweetening agents flavoring agents and coloring agents, e .g., comprising a flavoring ag nt in an amount of from 0.5% to 3.0%; 0.3% to 1.6%; or about 1.2%.

1.12. Any foregoing composition comprising 10% sodium chloride, 0,5% to 1.5% cairageenan; optionally, 0.1% to 0.5% CMC 2000sj about 63% sorbitoL about 1% polyethylene glycol; 3% to 4% thickener silica; 5% to 10% abrasive silica thickener; about 2% sodium lauryl sulfate; about 1% poloxamer 407; and 0.2% to 0,3% so dium fluoride.

[0044] The inv ntion further provides, in another enifoodimenl, a method for reducing bacterial growth in a toothpaste comprising a silica abrasive, comprising including at least 5% sodium chloride; from 7.5% to 12.5% sodium chloride ; or about 10% sodium chloride in the toothpaste.

[0045] The invention further provides, in another enifoodimenl, a toothpaste comprising sodium chloride in an amount of from 8% to 12%; a binder system comprising from 0.5% to 1 .5% carrageenan, and, optionally, from 0.1% to 0.5% carboxymethylce llulose ; an abrasive ; one or more detergents; one or more disp rsants; and a fluoride source; wherein the toothpaste is striped, translucent, and contains more sodium c hloride by we ight than abrasive .

[0046] The inv ntion further provides, in another embodim nt, a method for reducing bacterial growth in an oral cavity, comprising contacting the oral cavity with a toothpaste of any of Compositions 1, et seq.

[0047] The invention further provides, in another embodiment, the use of carrageenan to stabilise viscosity in a high-salt toothpaste or in the manufacture of a toothpaste according to any of Compositions 1, et se .

[0048] The invention further provides, in another en^odiment, a method for stabilizing a toothpaste having high salt conc ntration, comprising mixing the salt with a binder system, wherein the binder system comprises from 0.5% to 1 .5% carrageenan, and, optionally, from 0.1% to 0.5% carboxymethylcellulose. [0049] The following examples are further illustrative of the nature of the present invention, but it is understood that the invention is not limited thereto. All amounts and proportions referr d to herein and in the appended claims are by weight, unless otherwise indicated.

Example 1 - Binder Ξ ystem Determination

[0050] Several thick ner binder systems containing high sodium chloride concentrations were evaluated for their ability to maintain viscosity over time. Table 1 shows the compositions of experimental formulas 1-9, and control formula 10. Formulas 1-S contain 10% sodium chloride and formula 9 contains 5% sodium chloride .

Table 1

Com ositions of Toothpaste Formulas

[0051] The viscosity data obtains d for the thicke nerbinder systems are shown belo in Table 2.

Table 2: Viscosit data for different i ckerierbinder s st ms ( x 10 c s)

[0052] The viscosity data in Table 2 demonstrate significant differences for the three types of gum cooperation systems with high salt level toothpaste . Formulas 1 and 2 are utilise Ihickener silica, Xanthan gum and carboxymelhylcellulose for the thickener / binder system. It n be seen that the viscosity of these compositions is unstable, increasing significantly with time . Starting at an initial low initial viscosity of about 14- 20*1ϋ ⁺ cps, the aging viscosity increases to a much greater value (greater than 100* 10 ⁺ cps) witiun thr months. The resulting toothpaste is hard to squeeze out from the tubes at this viscosity. Accoiidingly, this type of gum system has unstable viscosity in high salt level toothpaste , which rende rs it unsuitable to preparation of a striped toothpaste .

[0053] Formulas 3, 4 and 5 have high levels of thickener sili a and also contain carbo-iymethylce llulose . The viscosity data show that the viscosities of these compositions are more stable than those of Formulas 1 and 2, but nevertheless also have an in reasing trend over time . Further, as discussed below, this system does not produ e a good stripe quality toothpaste . While not wishing to be bound by any partic ular theory, it is believed that carboxymethylcellulose is a linear structure gum, and cannot form the 3-dimentional structure ne ssary to ontrol the olor mixing, resulting in a poor quality stripe toothpaste.

[0054] Formulas 6, 7, 8 and 9 have the carrage nan-containing binder / thickener system of the pres nt invention. It can be seen from the Table 2 that this system has a stable viscosity trend. Thus, it is believed that the presence of carrageenan in the binder/thickener system affords the maintenance and control of viscosity in high-level salt (e.g., sodium chloride) toothpaste.

Example 2 - Rheology Properties Determination

[0055] R ieology and stripe fiUing prop rties are determined for toothpaste compositions having formulae 7, 8 and 9 as des ribed in Table 1 above. [0056] The control toothpaste is a commer ial striped toothpaste which delivers a good striping quality which does not contain sodium chloride, and includes 1 .0% Carrageenan, and 15/5/1 .5 Silic (i.e. 15% abrasive siliva; 5% Sorbosil AC43, and 1 .5% thicke er sili a).

[0057] A thiiiotropic test is used to predict if a formula can be striped with good stripe quality. A well-defined lluxotropic loop indicates that the formula can be striped with good quality while the absence of a well-defined bop suggests that the formula cannot provide good stripe. We find the hysteresis loop test to be a useful way to measure thixotropy We linearly increase the shear rate from zero to a maxiinum value and then to return at the same rate to zero. Thus a constant bop behavior is seen.

[0058] The following four samples are used in the tiuxotropic test:

Sample 1 : Commercial toothpaste contaming 1 .0% Carrageenan, and 15% abrasive thickener silica; 5% Sorbosil AC43, and 1 .5% thickener silica (control sample ide ntic al to Control as de sc ribed in Table 1 , abov ) ,

Sample 2: F-xp rim ntal Sample containing 0.8% Carrage nan, 8% abrasive silica and 3% thicken r sili ; and 10% sodium chbride (identical to Formula 7 from Table

1, above);

Sample 3: Experimental Sample containing 0.7% Carrageenan, 0.15% CMC 2000s, 8% abrasive silica; 3% thickener silica; and 10% sodium chbride (identical to Formula 8 from Table 1, above).

Sample 4: Experimental Sample containing 0.8% Carrageenan, 0.3% CMC 2000s, 8% abrasive silica; 4% thickener sili a; and 5% sodium chbride (identical to Formula 9 from Table 1, above).

Sample 1 corresponds to the control and Samples 2, 3 and 4 correspond to formulae 7, 8, and 9 respectively in above Table 1 .

[0059] The results of the thixotropic test are shown in Fig. 1. All three experim ntal samples show bop c urves characteristic of materials possessing thixotropy Accordingly, while not wishing to be bound by any particular theory, it is b lieved that the carrage nan-based thick ner provides for the formation of a three-dimensbnal structure, which aids in stabilizing the viscosity of the toothpaste during 3 months a celerated aging.

Example 3 - Stripe Quality Determination

[0060] The stripe quality index (SQI) test is used to determine if the quality of a stripe is acceptable. A commercially acceptable stripe is considered to be a stripe which has a SQI of 3 or above . The stripe quality is tested by extruding the striped toothpaste and quantitatively evaluating the stripe quality according to a stripe quality index numerical scale, where 1 represents the worst stripe quality and 5 represents the best stripe quality. Ten data points are employed for the testing of each toothpaste, each data point corresponding to a respective property of a respective extrusion (A = stripe definition, B = stripe consistency of the first short ribbons during extrusion, C = stripe definition, D = stripe consistency of the first long ribbons during extrusion, E = stripe definition, F = stripe consistency of the second short ribbons during extrusion; G = stripe definition, H = stripe consistency of the second long ribbons during extrusion; I = stripe definition, J = stripe consistency of the last short ribbons during extrusion).

Toothpaste Pre aration:

( 1 ) A proportion of humectant (sorbitol, glyc erine , etc ) are added into ge 1 tank.

(2) Pigment hot water are added into gel tank.

(3) xture of Gums (Carragee nan, CMC, Xanthan gum etc) with minor ingredients (NaF/ MFP, Saccharin) are dispersed into gel tank and increase to definite temperature and mixing completely.

(4) The gel is transferred into the main mixer at full va um.

(5) The silica is allowed to be sucked into the mixer by the vacuum and mixed completely.

(6) Add the surfactant (SLS, Poloxamer 407) into mixer and mix completely.

(7) Inhale Sodium Chloride and flavour into mixer and mix completely with full va uum.

[0061] The folio wing four sam pies are used in the SQI test:

Sample 1 : Commercial toothpaste containing 1 .0% Carrageenan, and 15% abrasive thickener silica; 5% Sorbosil AC43, and 1 .5% thickener silica (control sample ide ntic al to Control as de sc ribed in Table 1 , above ) ; Sample 2: Experimental Sample containing 0.8% Carrageenan, 8% abrasive silica and 3% thickener silic ; and 10% sodium c hloride (identical to Formula ? from Table 1, above);

Sample 3: Experimental Sample containing 0.?% Carrageenan, 0.15% CMC 2000s, 8% abrasive sili ; 3% thicken r silica; and 10% sodium chloride (identical to Formula 8 from Table 1, above).

S mple 4: Expe rime ntal Sample containing 0.8% Carrageenan, 0.3% CMC 2000s, 8% abrasive silica; 4% thickener silica; and 5% sodium chloride (identical to Formula 9 from Table 1, above).

All three e perimental samples produce a good stripe quality toothpaste, and each has an attractive translucent appearance.

[0062] While the present invention has been described with reference to embodiments, it will be understood by those skilled in the art that various modifications and variations may be made therein without departing from the scope of the present invention as defined by the appended claims.