Field of the Invention The invention relates to a toothpaste composition with enhanced flavor release and reduced stringiness. In particular, the invention is related to a toothpaste composition comprising microcrystalline cellulose co-processed with a surfactant, with a hydrocolloid, or with a hydrocolloid and an attriting agent.

Background of the Invention Toothpaste compositions, also known as toothpastes or dentifrice compositions, typically contain a polishing agent or abrasive, a humectant, a binder or thickening agent, a surface active agent, water, and as well as agents that provide therapeutic or cosmetic benefits, such as fluorides, flavorings, and sweeteners. The binder prevents separation of ingredients in storage, promote dispersibility and retention in use, as on a toothbrush.

The most widely used binders are cellulose gums because they are inexpensive and their quality can be closely controlled. Carboxymethyl cellulose is widely used in silica containing toothpaste compositions, but such compositions often exhibit excessive"stringiness. "That is, the toothpaste forms an excessive amount of a stringy tail when extruded from a tube.

Stringiness is important in toothpaste manufacturing because toothpaste is typically packaged in laminated tubes using high speed filling lines. To meet the demands of high speed production, toothpaste ribbons that cut off sharply from the tube are necessary. If any toothpaste remains in the sealing portion of the laminated tube, tube sealing could be faulty. In addition, a toothpaste string coming out of the tube could cause blackening

on the outside portion of the tube in the sealing area due to burning while it is being sealed.

Consumers view stringiness as aesthetically unpleasing and have come to expect a sharp-breaking paste. Further, the tail can get onto the threads of the cap, neck and other portions of the tube giving a messy appearance to the product. However, any solution to this problem must maintain the properties to which the consumer is accustomed, such as appealing taste, good cleansing effect, easy to rinse, excellent mouth feel, and chemical and physical stability. Furthermore, these properties should be provided in a toothpaste that is cost effective for the consumer. Thus, a need exists for a non-stringy toothpaste composition that has an appealing taste and the other properties that make it acceptable to the consumer.

Summary of the Invention A toothpaste composition with enhanced flavor release and reduced stringiness is disclosed. The composition comprises an abrasive, a humectant, a binder, a co-binder, a surface active agent, and water; in which: the co-binder is colloidal microcrystalline cellulose co-processed with a surfactant; colloidal microcrystalline cellulose co-processed with a hydrocolloid ; colloidal microcrystalline cellulose co-processed with a hydrocolloid and an attriting agent; a mixture of colloidal microcrystalline cellulose co-processed with a hydrocolloid and an attriting agent in which the microcrystalline cellulose to attriting agent ratio is about 85: 15 to about 30: 70 by weight and the mean particle size of the attriting agent is about 0.1 to about 8 microns; colloidal microcrystalline cellulose co-processed with a hydrocolloid and an inorganic salt, in which microcrystalline cellulose have an average particle size less than 10 microns, and when the hydrocolloid is carrageenan, at least about 50% of the particles have a particle size less than 3.5 microns, when the hydrocolloid is a hydrocolloid other than carrageenan, at least about 30% of the particles have a particle size less

than 3.5 microns, and when the hydrocolloid is a combination of carrageenan and another colloid, at least about 20% of the particles have a particle size less than 3.5 microns; or a mixture thereof; with the proviso that when the abrasive is silica, the co-binder is not colloidal microcrystalline cellulose co-processed with one of xanthan, alginate, and a cellulose gum in the absence of a water soluble inorganic salt.

Detailed Description of the Invention Unless the context indicates otherwise, in the specification and claims, the terms abrasive, humectant, binder, co-binder, hydrocolloid, surfactant, surface active agent, flavoring, flavoring agent, sweetener, sweetening agent, antislip agent, attriting agent, and similar terms also include mixtures of such materials. Unless otherwise specified, all percentages are percentages by weight.

The toothpaste compositions comprise an abrasive, a humectant, a binder, a surface active agent, water, and, optionally, other materials that are conventional components of toothpaste compositions, The solid and liquid components of toothpaste compositions are formulated to produce a product that is an extrudable, creamy material.

The binder, or thickener, builds viscosity, provide a desirable consistency and thixotropy, and prevents separation of the ingredients during storage and use. Suitable thickeners include cellulose derivatives ("cellulose gums") such as carboxymethyl cellulose (CMC), methyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, and mixtures thereof; polyvinyl pyrrolidone ; xanthan; carrageenans such as iota- carrageenan, kappa-carrageenan, kappa2-carrageenan, lambda- carrageenan, and mixtures thereof; guar gum; gum karaya; gum arabic; gum tragacanth; and mixtures thereof. Carrageenan containing toothpaste is disclosed in Randive, U. S. Pat. No. 6,162, 418, incorporated herein by reference. Silica thickeners, such as hydrated silica and colloidal silica may also be used. Mixtures, such as a mixture of carboxymethyl cellulose

and colloidal silica, may be used. Silica thickeners are disclosed, for example, in Niemi, U. S. Pat. No. 6,342, 205.

The co-binder is colloidal microcrystalline cellulose co-processed either with a surfactant, co-processed with a hydrocolloid, or co-processed with a hydrocolloid and an attriting agent. Mixtures and/or blends of two or more co-binders may also be used.

Microcrystalline cellulose is a purified, partially depolymerized cellulose. It may be produced by the hydrolysis procedure described, for example, in Durand, U. S. Pat. No. 3,539, 365, and Battista, U. S. Pat. No.

2,978, 446. In this procedure, a source of cellulose, preferably alpha- cellulose in the form of a pulp from fibrous plants, is treated with a mineral acid, preferably hydrochloric acid. The resulting crystallite aggregates of microcrystalline cellulose are then separated from the reaction mixture and washed to remove degraded by-products. The resulting wet mass, generally containing 40 to 60 wt% water, is referred to as hydrolyzed cellulose, microcrystalline cellulose, microcrystalline cellulose wetcake, or simply wetcake. The steam explosion process, in which wood chips or other cellulosic materials are placed in a chamber into which super-heated steam is introduced, is disclosed in Ha, U. S. Pat. No. 5,769, 934.

Colloidal microcrystalline cellulose is obtained by reducing the particle size of microcrystalline cellulose and stabilizing the attrited particles to avoid formation of hard aggregates. Techniques for reducing the particle size of microcrystalline cellulose are disclosed in Durand, U. S. Pat. No.

3,539, 365; Krawczyk, U. S. Pat. No. 6,025, 037; Venables, U. S. Pat. No.

6,037, 080, and Tuason, U. S. Pat. No. 6,391, 368 and WO 03/09676.

The colloidal microcrystalline cellulose particles have a mean particle size of about 0.1 to about 8 microns, preferably about 0.1 to less than about 1.0 micron, more preferably about 0.1 to about 0.9 micron, and most preferably about 0.1 to about 0.6 micron, as determined by the Horiba Cappa 700 particle size analyzer. Generally, any particle size distribution is acceptable, as long as the mean particle size is within the desired range, and preferably the mean particle size of finely divided microcrystalline

cellulose that is substantially colloidal in particle size is less than about 10 microns.

Colloidal microcrystalline cellulose co-processed with a surfactant may be used as a co-binder in the toothpaste compositions. A"surfactant" has a HLB (hydrophilic/lipophilic balance) of about 1 to about 40. Methods for preparing colloidal microcrystalline cellulose co-processed with a surfactant are disclosed, for example, in McGinley, U. S. Pat. No.

5,736, 177, and Krawczyk, U. S. Pat. No. 6,025, 007. Numerous surfactants are known. Useful surfactants include, for example, lecithin ; monoglycerides ; mono-and diglycerides ; acetylated monoglycerides ; ethoxylated monoglycerides ; sorbitan esters; sucrose esters; monostearates; monoglyceride or diglyceride esters, including esters of acids such as acetic acid, lactic acid and succinic acid and including diacetyl tartaric acid esters of mono-or diglycerides ; propylene glycol monoesters; polyglycerol esters of fatty acids; polysorbates ; sodium stearyl lactylate ; and ethoxylates, sulfates, and sulfates of ethoxylates of alkyl alcohols in which the alkyl group contains about 8 to about 18 carbon atoms, such as sodium cetyl sulfate, sodium lauryl sulfate (SLS), and disodium lauryl sulfosuccinate. Colloidal microcrystalline cellulose co-processed with sodium stearyl lactylate is commercially available from FMC Corporation as AVICEL (g) SD 1340.

The co-processed microcrystalline cellulose may contain about 60% to about 95% by weight finely divided microcrystalline cellulose and about 5% to about 40% by weight surfactant co-processed with the cellulose, all percentages based on the total weight of the co-processed material.

Preferably, the microcrystalline cellulose comprises about 70 to about 95 wt% of the co-processed material. Preferably, the surfactant comprises about 5 to about 30 wt% of the co-processed material. More preferably, the surfactant comprises about 10 to about 30 wt% of the co-processed material.

Surprisingly, It has also been found that colloidal microcrystalline cellulose co-processed with a hydrocolloid reduces stringiness and

enhances the properties that are appealing to the consumer when the toothpaste composition contains either calcium diphosphate or calcium carbonate as the abrasive. Suitable hydrocolloids include, for example, cellulose derivatives such as carboxymethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, and hydroxyethyl cellulose ; gums such as guar, locust bean, gum arabic, xanthan, tragacanth and karaya; seaweed extracts such as kappa-carrageenan, kappa2-carrageenan, iota- carrageenan, lambda-carrageenan, and alginates ; and starches such as maltodextrin, hydrolyzed cereal solids, and pectin.

Colloidal microcrystalline cellulose co-processed with carboxymethyl cellulose (CMC), starch, preferably starch having a low amylose content, and a diluent, maltodextrin, whey, or non-fat dry milk solids, preferably maltodextrin, is disclosed in Tuason, U. S. Pat. No. 4,980, 193. Colloidal microcrystalline cellulose co-processed with alginate is disclosed in Tuason, U. S. Pat. No. 5,366, 742. Colloidal microcrystalline cellulose co- processed with low viscosity alginate complex is disclosed in Augello, U. S.

Pat. No. 5,985, 323. Colloidal microcrystalline cellulose co-processed with a galactomannan gum, such as locust bean or guar gum, is disclosed in McGinley, U. S. Pat. No. 5,192, 569. Colloidal microcrystalline cellulose co- processed with iota-carrageenan is disclosed in Tuason, U. S. Pat. No.

6,391, 368. Colloidal microcrystalline cellulose co-processed with sodium carboxymethyl cellulose (MCC/CMC) is available from FMC Corporation as AVICELO RC-591.

Colloidal microcrystalline cellulose co-processed with a hydrocolloid, such as carrageenan, and a water soluble salt is disclosed in Tuason, WO 03/096976 (PCT/US03/15146), incorporated herein by reference. The co- processed colloidal microcrystalline cellulose is prepared by subjecting a high solids mixture of microcrystalline cellulose and a hydrocolloid to high shear forces in the presence of an antislip agent. Although the antislip agent may be essentially any water soluble salt, salts such as sodium chloride, potassium chloride, calcium lactate, calcium tartrate, calcium citrate, or calcium monophosphate, and especially calcium chloride are

preferred antislip agents. The hydrocolloid is added as a dry powder.

During processing, it is important that the salt is added before the uniform wetting and swelling of the hydrocolloid powder. The particles have an average particle size less than 10 microns, measured as described above.

When the hydrocolloid is carrageenan, at least about 50% of the particles have a particle size less than 3.5 microns. When the hydrocolloid is a hydrocolloid other than carrageenan, at least about 30% of the particles have a particle size less than 3.5 microns. When the hydrocolloid is a combination of carrageenan and another colloid, at least about 20% of the particles have a particle size less than 3.5 microns.

Colloidal microcrystalline cellulose co-processed with both a hydrocolloid and an attriting agent may be used as the co-binder. Suitable hydrocolloids are listed above. Suitable attriting agents include calcium carbonate (limestone, chalk), dicalcium phosphate, tricalcium phosphate, zinc carbonate, zinc hydroxide, magnesium phosphate, barium carbonate, barium sulfate, ferrous carbonate, aluminum hydroxide, magnesium hydroxide, and magnesium aluminum hydroxide. Other materials useful as attriting aids include silica, various clays, silicates, silicon dioxide, talc, titanium dioxide, and partially soluble organic materials, such as lactose.

Preferred attriting agents include calcium carbonate, dicalcium phosphate, and silica, all of which are used as abrasives in toothpaste compositions.

Methods for making colloidal microcrystalline cellulose co-processed with a hydrocolloid and an attriting agent are described, for example, in Venable U. S. Patent No. 6,037, 380.

The weight ratio of microcrystalline cellulose to attriting agent is typically about 85: 15 to about 30: 70, more typically about 70: 30 to about 40: 60. The hydrocolloid is typically about 5 to 30 wt%, preferably 5% to 15 wt%, of the microcrystalline cellulose ; that is, the weight ratio of microcrystalline cellulose to hydrocolloid is about 95: 5 to about 70: 30.

Equivalent results may be achieved by the use of a mixture of an attriting agent and microcrystalline cellulose co-processed with a hydrocolloid when the particles of attriting agent have the appropriate

particle size and the ratio of microcrystalline cellulose and attriting agent falls within the appropriate limits. As described above, the appropriate particle size for the particles of attriting agent is a mean particle size of 0.1 to about 8 microns, preferably about 0.1 to less than about 1.0 micron, more preferably about 0.1 to about 0.9 micron, and most preferably about 0.1 to about 0.6 micron, as determined by the Horiba Cappa 700 particle size analyzer. For the mixture of microcrystalline cellulose and attriting agent, the appropriate weight ratio of microcrystalline cellulose to attriting agent may be about 95: 5 microcrystalline cellulose to attriting agent to about 5: 95, typically 90: 10 to 30: 70, more typically 85: 15 to about 55: 45.

The toothpaste composition comprises an abrasive, which may also be called a polishing agent. Suitable abrasives, or polishing agents, include finely divided water-insoluble powdered materials having no or very low water solubility, typically having a particle size of about 1 to 40 microns in diameter, more typically about 2 to 20 microns in diameter, with normal particle size distributions. These materials have polishing activity without being overly abrasive. Typical abrasives include : calcium-based polishing agents, such as dicalcium phosphate dihydrate (generally known as dicalcium phosphate), tricalcium phosphate, calcium carbonate (such as limestone, natural chalk, or precipitated chalk), calcium pyrophosphate, calcium silicate, and calcium aluminate ; magnesium carbonate; magnesium phosphate; sodium metaphosphate; amorphous silica ; crystalline silica ; precipitated silica ; complex aluminosilicate ; aluminum hydroxide; non- colloidal microcrystalline cellulose, such as AVICELO PH 105 non-colloidal microcrystalline cellulose ; aluminosilicates, bentonite, talc, aluminum oxide, silica xerogels, and mixtures thereof. More typical abrasives are dicalcium phosphate, calcium carbonate, and silica. As described above, non- colloidal microcrystalline cellulose differs from colloidal microcrystalline cellulose in particle size.

The vehicle is orally acceptable and is comprised of water and a humectant. The humectant provides mouthfeel and also prevents the toothpaste composition form drying out. Typical humectants are polyols of

three to six carbons in which each carbon is hydroxylated, and mixtures thereof, such as glycerol (glycerin), sorbitol, polyethylene glycol, polyoxyethylene glycol, mannitol, xylitol, and other sugar alcohols. Sorbitol and glycerol are preferred. After the other ingredients have been accounted for, water makes up the balance of the composition. The water is preferably deionized and free of impurities.

Toothpaste compositions also comprise a surface active agent to emulsify or otherwise uniformly disperse toothpaste components. The surface active agents are typically anionic or nonionic surface active agents, or mixtures thereof. Examples of suitable surface active agents include water-soluble salts of higher fatty acid monoglyceride monosulfates ; higher alkyl sulfates ; higher alkyl aryl sulfonates ; higher alkyl sulfoacetates ; higher fatty acid esters of 1,2 dihydroxy propane sulfonate ; substantially saturated higher aliphatic acyl amides of lower aliphatic amino carboxylic acid compounds, such as those having 12 to 16 carbon atoms in the fatty acid, alkyl or acyl radicals; higher olefin sulfonates, higher alkyl poly-lower alkoxy (of 3 to 100 alkoxy groups) sulfates, and fatty acid soaps.

Examples of these anionic surface active agents include sodium lauryl sulfate (SLS), sodium hydrogenated coconut oil fatty acids monoglyceride monosulfate, sodium dodecyl benzene sulfonate, sodium lauryl sulfoacetates, sodium N-lauryl sarcosinate, and sodium cocate. Suitable types of nonionic surface active agents include chains of lower alkyene oxides such as ethylene oxide and propylene oxide. A commonly used surface active agent is sodium lauryl sulfate.

The toothpaste composition may comprise a number of other optional ingredients. Agents that provide therapeutic or cosmetic benefits may be present, such as enamel hardening agents, tartar control agents, whitening agents, and antibacterial agents. One or more sweeteners and flavorings may be added for consumer satisfaction. Other materials that are conventional components of toothpaste compositions, such as opacifers and colorants, may also be present.

Examples of flavoring (flavoring materials or flavoring agents)

include: menthol ; carvone; anethole ; methyl salicylate ; and the oils of spearmint, peppermint, wintergreen, sassafras, clove, sage, eucalyptus, marjoram, cinnamon, lemon, lime, grapefruit, tangerine, and orange.

Examples of sweeteners (sweetening agents) include sucrose, lactose, maltose, sorbitol, xylitol, sodium cyclamate, perillartine, L-aspartyl-L- phenylalanine methyl ester (aspartame), and saccharine. Pyrophosphate salts having anti-tartar efficacy such as a dialkali or tetra-alkali metal pyrophosphate salts such as Na4P207 (TSPP), K4P207, Na2K2P207, Na2K2H207, and K2H2P207, long chain polyphosphates such as sodium hexametaphosphate, and cyclic phosphates such as sodium trimetaphosphate may be present in the toothpaste composition.

Examples of hardening agents are fluoride salts such as sodium fluoride, potassium fluoride, calcium fluoride, zinc fluoride, stannous fluoride, zinc ammonium fluoride, sodium monofluorophosphate, potassium monofluorophosphate, and laurylamine hydrofluoride.

Antibacterial agents may also be included in the toothpaste compositions. Especially useful are non-cationic antibacterial agents that are based on phenolic and bisphenolic compounds, halogenated diphenyl ether, benzoate esters and carbanilides, such as sodium benzoate; 4- chlorophenol, 2, 2'-trichloro-2-hydroxy-diphenyl ether (triclosan) ; esters of p- hydroxybenzoic acid, especially the methyl, ethyl (ethyl parasept), propyl (propyl parasept), butyl (butyl parasept), and benzyl esters; 3,4, 4'- trichlorocarbanalide and 3,3', 4-trichlorocarbanilide. A preferred antimicrobial agent is triclosan. Nonionic antimicrobial agents such as sesquiterpene alcohols such as merolidol and bisabolol are also useful.

Whitening agents may be present in the toothpaste composition.

Useful whitening agents are oxidizing agents such as calcium peroxide, urea peroxide, peracetic acid, and sodium percarbonate. An opacifier, such as titanium dioxide, may be added to make the toothpaste opaque or to increase its opacity.

The toothpaste composition may also comprise other ingredients that are conventional components of toothpaste compositions, including, for

example, desensitizing agents for sensitive teeth such as sodium nitrate; orally acceptable colorants such beta-carotene, chlorophyllin, FD&C Yellow #5, FD&C Yellow #6, FD&C Blue #2, FD&C Red #4, FD&C Green #6, FD&C Yellow #10, FD&C Red #40, D&C Green #5, D&C Red #30 lake, and FD&C Blue #1 lake ; healing agents, such as rose-seed oil ; chelating/sequestering agents, such as citrates; vitamins, such as vitamin C and vitamin E; amino acids; proteins; antibiotics; anti-enzymes; enzymes; pH control agents (buffers); antioxidants; and preservatives.

The toothpaste composition typically comprises about 0.05 to 3.0 wt% of the binder, based on the total weight of the toothpaste composition. When carrageenan or xanthan is used as the binder, less binder is typically required than when a cellulose derivative such as carboxymethyl cellulose is used as the binder. When a cellulose derivative such as carboxymethyl cellulose is used as the binder, the binder typically comprises about 0.25 to about 3.0 wt% and preferably about 1.0 to about 1.5 wt% of the toothpaste composition. When carrageenan or a mixture of carrageenan is used as the binder, the binder typically comprises about 0.05 to 2.5 wt% of carrageenan. Processes for preparing low carrageenan toothpastes are disclosed in Ballard, U. S. Pat. No. 6,187, 293.

The toothpaste composition typically comprises about 0. 1 % to 3.0% wt%, more typically about 0.2 to 2.0 wt%, even more typically about 0.3 to 1.5 wt%, of the co-binder, based on the total weight of the toothpaste composition. As long as sufficient co-binder is present in the composition to control rheology, the composition may also comprise larger microcrystalline cellulose particles, for example, particles that have not been attrited or only partially attrited, provided the composition does not become grainy.

When dicalcium phosphate (DCP) is used as the abrasive, the toothpaste composition typically comprises about 25 to 55 wt%, more typically about 35 to 53 wt% of dicalcium phosphate. When calcium carbonate is used as the abrasive, the composition typically comprises about 25 to 55 wt%, more typically about 35 to 50 wt%, of calcium

carbonate. When silica is used as the abrasive, the composition typically comprises about 15 to 30 wt% silica.

The toothpaste composition typically comprises about 8 to 60 wt% humectant, on an absolute basis. Sorbitol, for example, is commercially available as 70% sorbitol/30% water mixture. "On an absolute basis" means the amount of humectant, exclusive of any water that is present in the humectant. The amount of humectant will depend on whether or not the toothpaste is a high water toothpaste. As the amount of water in the toothpaste increases, the amount of humectant typically decreases.

Although the water content varies widely, most toothpaste compositions comprise about 10 to about 35 wt%, more typically about 10 to about 30 wt%, water. However, the co-binders described herein may used as the co-binder in high moisture toothpastes. High moisture toothpastes typically comprise more than about 30 to 35 wt% water, more typically more than about 40 wt% water, typically about 50 wt% or about 60 wt% water to about 70 wt% water. High moisture toothpastes, and their preparation, are described, for example, in Randive, U. S. Pat. No.

6,159, 446, incorporated herein by reference.

The toothpaste composition typically comprises about 0.8 to about 3.0 wt%, preferably about 1.0 to about 2.0 wt%, of the surface active agent.

When a flavoring is present, the toothpaste composition typically comprises about 0.1 to about 2.0 wt%, more typically about 0.5 to about 1.5 wt%, of the flavoring.. When a sweetener is present, the toothpaste composition typically comprises about 0.1 to about 2 wt% of the sweetener . When an anti-tartar agent is present, the toothpaste composition typically comprises about 0.5% to about 8.0 wt% of the anti-tarter agent. When an anti-bacterial agent is present, the toothpaste composition typically comprises about 0.03 to about 1 wt% of the antibacterial agent. When a whitening agent is present, the toothpaste composition typically comprises about 0.1 to about 5 wt%, preferably about 0.5 to about 2 wt%, of the whitening agent. When a pyrophosphate salt is present, the toothpaste composition typically comprises about 0.5 to about 8.0 wt%, preferably

about 1.5 to about 3 wt%, of the pyrophosphate salt. When a hardening agent is present, it typically comprises about 0.1 to about 5 wt% of the toothpaste composition. When present, other ingredients, such as dyes and opacifiers, are present in effective amounts, that is, each ingredient is present in the amount necessary to achieve its particular purpose.

The toothpaste compositions can be prepared using either the hot process or the ambient process, and either a batch process or a continuous process may be used. The ambient process is sometimes called the cold process. The hot process is described, for example, in Scott, U. S. Pat. No.

4,353, 890, and Ballard, U. S. Pat. No. 6,187, 293, the disclosures of which are incorporated herein by reference. A continuous process for the manufacture of toothpaste is disclosed, for example, in Ballard, U. S. Pat.

No. 6,187, 293, especially in Figure 1 and the accompanying text, the disclosure of which is incorporated herein by reference. An example of the hot process that can be used to prepare the toothpaste compositions is given in the Examples. The ambient process is the same as the hot process, except that steps (2) and (3) of the process given in the Examples are carried out at about 25°C.

The advantageous properties of this invention can be observed by reference to the following examples, which illustrate but do not limit the invention.

EXAMPLES Glossary AVICELO RC-591 Colloidal microcrystalline cellulose co-processed with sodium carboxymethyl cellulose in a ratio of 89/11, by weight (FMC, Philadelphia, PA USA) MCC/CMC AVICELO RC-591 colloidal microcrystalline cellulose co-processed with sodium carboxymethyl cellulose (FMC, Philadelphia, PA USA) MCC/SLS Colloidal microcrystalline cellulose co-processed with sodium lauryl sulfate MCC/CMC/CaC03 Colloidal microcrystalline cellulose co-processed with

carboxymethyl cellulose and calcium carbonate DCP Dicalcium phosphate dihydrate, commonly called dicalcium phosphate SLS Sodium lauryl sulfate SMFP Sodium monofluorophosphate TSPP Tetrasodium pyrophosphate (Na4P207) TP-329 Binder containing a mixture of iota, lambda, and kappa2 carrageenans (FMC, Philadelphia, PA USA) TP-389 Binder containing primarily a mixture of iota carrageenans (FMC, Philadelphia, PA USA) TP 399 Binder containing primarily a mixture of iota- carrageenans (FMC, Philadelphia, PA USA) ZEODENT 113 Amorphous silica (J. M. Huber, Edison, NJ USA) ZEODENTS) 165 Amorphous silica (J. M. Huber, Edison, NJ USA) General Procedures Sample Preparation The toothpaste compositions were prepared using the hot process by the following procedure: (1) The binder and the colloidal microcrystalline cellulose are dispersed into the humectant with a high-speed stirrer and stirred, for example, for about 10 minutes to form a gel.

(2) The water can then be heated to about 80°C and added to the humectant and binder/colloidal microcrystalline cellulose mixture with stirring continuing for 15 minutes while the temperature is maintained at 60- 70°C.

(3) The dry ingredients, such as sodium saccharin, sodium benzoate, etc, exclusive of the abrasive are dry blended. The dry blend is stirred into the binder slurry and stirred for 15 minutes while the temperature is maintained at 60-70°C.

(4) The resulting gel (elixir) is transferred to a low speed Rossez mixer with a vacuum attachment. The Rossw mixer is a double planetary gear, two-paddle mixer, which operates at 20 to 100 revolutions per minute

and can be operated under vacuum.

(5) The abrasive (polishing agent) is added sequentially to the elixir and mixed for 15 minutes under vacuum (at least 720 mm Hg.).

(6) Flavoring is added to the elixir and mixed for 10 minutes in the Ross mixer under full vacuum.

(7) The surfactant, such as sodium lauryl sulfate (SLS), is added to the mix and mixing is continued under vacuum for 20 minutes.

(8) A sample is withdrawn for testing, and the batch is discharged for filling tubes or other dispensers.

Toothpaste compositions comprising each of three abrasives were formulated. Binder was added to each composition as indicated in the specific example and the amount of water was adjusted accordingly to produce 100 parts.

COMPOSITION 1-CHALK ABRASIVE Ingredient Parts Glycerin 10.00 Sorbitol 17. 00 Saccharin 0.20 Sodium benzoate 0.30 Chalk 46.00 Flavoring 1.00 SLS 2.00 Water 22. 70

COMPOSITION 2-SILICA ABRASIVE Ingredient Parts Sorbitol 68.00 Saccharin 0.20 Sodium benzoate 0.20 ZEODENT (g) 165 7.00 ZEODENT 113 11.00 Flavoring 1.00 SLS 2. 00 Water 10. 10 COMPOSITION 3-DICALCIUM PHOSPHATE ABRASIVE Ingredient Parts Glycerin 22.00 Saccharin 0.20 TSPP 0.25 SMFP 0.76 DCP 52.25 Flavoring 1.00 SLS 1.50 Water 21. 44 Sensory Evaluation All evaluations were carried out under a controlled environment in a university food department's laboratory where testing of food samples is carried out. Panelists were selected from research students studying for their masters or doctoral degree. An average of about 10 panelists evaluated each set of samples, with minimum 8 and maximum 12 for the corresponding sets.

Each panelist tested no more than two samples per day. Panelists did not eat or drink (other than water) for two hours prior to the test. Each panelist was provided with a new toothbrush per set. Although the weight of toothpaste used per evaluation was not measured, the length of the toothpaste ribbon was prescribed. Every panelist rinsed their mouth with tap water before initiating evaluation. Each sample was brushed for 1 minute. No brushing regimen was prescribed.

Nine sensory parameters were evaluated for each toothpaste

composition. The parameters were: (1) appearance; (2) flavor, during and after brushing; (3) consistency, before brushing; (4) grittiness; (5) chalky taste, during and after brushing; (6) foaming, during brushing; (7) cooling, after brushing; (8) freshness, after brushing; and (9) after taste. Each parameter was rated on a scale of 0-7, with 7 being the highest score, for a maximum score of 63. The observations were recorded on the standard sheets and later collated for all panelists. The averages of the ratings were converted to percents, with 100% being equal to a score of 63.

Head Space Analysis A sample toothpaste composition was placed in an ampoule and closed with an airtight rubber closure crimped with an aluminum clasp and heated in a water bath at 60°C. After 1 hour, the ampoule was removed from the bath and a sample immediately removed from the head space with a GC syringe inserted through the rubber closure. The sample was analyzed by gas chromatography using a Chemito 8520 gas chromatograph (Chemito Instruments PVT. LTD., Worli, Mumbai-400018- INDIA) with a flame ionization detector using a 2 meter column containing 10% FFAP (free fatty acid phase-modification of CARBOWAX (e) 20M) using a programmed temperature profile (2 min hold at 60°C, 22/min increase up to 120°C, 5-/min up to 200°C, and a 5 min hold at 200°C) with nitrogen carrier gas. Limonene, menthone, menthyl ester, menthol, cravone, methyl salicylate, and anethole were determined.

Examples 1 to 3 This example illustrates toothpaste compositions that contain chalk (calcium carbonate) as the abrasive. Toothpaste compositions were prepared by adding the binder and co-binder in Table 1-1 to Composition 1 shown in the general procedures.

Example 1 Chalk Containing Toothpaste Compositions Sample Added Binder Added Co-binder Rqtinn<BR> 1-1A 1.2% CMC None 55. 3% 1-1B 1% CMC 0.3% MCC/CMC 72.7% 1-1C 1.3% CMC 0.3% MCC/CMC/CaCO3 74.3% 1-lD 1.3% CMC 0.3% MCC/SLS 74. 9% 1-2A 1.0% Xanthan None 49. 8% 1-2B 1. 1% Xanthan 0.3% MCC/CMC 72.0% 1-2C 1. 1% Xanthan 0.3% MCC/CMC/CaCO3 71.9% 1-2D 1. 1% Xanthan 0.3% MCC/SLS 72.0% 1-3A 1.0% TP-329 None 51.4% 1-3B 0.8% TP-329 0.3% MCC/CMC 74. 3% 1-3C 0. 8% TP-329 0. 3% MCC/CMC/CaCO3 74.6% 1-3D 0.8% TP-329 0. 3% MCC/SLS 72. 9% 1-4A 0. 75% TP-389 None 48.7% 1-4B 0.75% TP-389 0.3% MCC/CMC 74.2% 1-4C 0.75% TP-389 0.3% MCC/CMC/CaCO3 71.9%<BR> 1-4D 0. 75% TP-389 0.3% MCC/SLS 72. 2% This example illustrates toothpaste compositions that contain silica as the abrasive. Toothpaste compositions were prepared by adding the binder and co-binder in Table 2-1 to Composition 2 shown in the general procedures.

Example 2 Silica Containing Toothpaste Compositions Sample Added Binder Added Co-binder Ratina<BR> 2-1 A 1.0% CMC None 55. 3% 2-1 B 0.85 CMC 0.3% MCC/CMC 74.8% 2-1 C 0.85% CMC 0.3% MCC/CMC/CaC03 77.0% 2-1 D 1.0% CMC 0.3% MCC/SLS 68.8% 2-2A 0.8% Xanthan None 64. 1% 2-2B 0.9% Xanthan 0.3% MCC/CMC 70.2% 2-2C 0.9% Xanthan 0.3% MCC/CMC/CaCO3 82. 1% 2-2D 0. 9% Xanthan 0. 3% MCC/SLS 74.3% 2-3A 0.5% TP-329 None 64.5% 2-3B 0.5% TP-329 0.3% MCC/CMC 72.7% 2-3C 0.5% TP-329 0.3% MCC/CMC/CaCO3 73.9% 2-3D 0.5% TP-329 0.3% MCC/SLS 71.4% 2-4A 0. 5% TP-389 None 56. 1 % 2-4B 0.45% TP-389 0.3% MCC/CMC 70.7% 2-4C 0.45% TP-389 0.3% MCC/CMC/CaCO3 75.4% 2-4D 0. 5% TP-389 0.3% MCC/SLS 73. 9% This example illustrates toothpaste compositions that contain dicalcium phosphate as the abrasive. Toothpaste compositions were prepared by adding the binder and co-binder in Table 3-1 to Composition 3 shown in the general procedures.

Example 3 Dicalcium Phosphate Containing Toothpaste Compositions Sample Added BinderAdded Co-binder Rating 3-1 A 1. 0% CMC None 69. 5% 3-1 B 0.85 CMC 0.3% MCC/CMC 70.2% 3-1 C 0.85% CMC 0.3% MCC/CMC/CaCO3 71. 1% 3-1 D 1.0% CMC 0.3% MCC/SLS 71.0% 3-2A 1.0% Xanthan None 67.0% 3-2B 0.9% Xanthan 0.3% MCC/CMC 67.7% 3-2C 0.9% Xanthan 0.3% MCC/CMC/CaCO3 69. 1 % 3-2D 0.9% Xanthan 0.3% MCC/SLS 71.8% 3-3A 0.8% TP-329 None 67. 1 % 3-3B 0.5% TP-329 0.3% MCC/CMC 71.8% 3-3C 0.5% TP-329 0.3% MCC/CMC/CaCO3 69.5% 3-3D 0.5% TP-329 0.3% MCC/SLS 72.0% 3-4A 0.8% TP-389 None 68.7% 3-4B 0.45% TP-389 0.3% MCC/CMC 70.0% 3-4C 0.45% TP-389 0.3% MCC/CMC/CaC03 72.0% 3-4D 0. 5% TP-389 0.3% MCC/SLS 68. 6% The average ratings for the twelve (4 binders; 3 abrasives) determinations for each co-binder are given in the Table below.

Co-Binder Average Rating None 59.8% MCC/CMC 71.8% MCC/CMC/CaCO3 73.6% MCC/SLS 72. 0% This shows that all the co-binders improve the sensory perception of the toothpaste.

The average rating for the determinations for each abrasive are shown below, No co-binder is the average of four determinations (four binders) and added co-binder is the average of twelve determinations (four binders, three co-binders) Abrasive No Co-binder Added Co-binder Calcium carbonate (chalk) 51.3 73.2% Silica 60.0 73.8% Dicalcium phosphate 68. 1 70. 4% This shows that the co-binders improve the sensory perception of the toothpaste for all three abrasives evaluated, but that the co-binders

were most effective in improving the sensory perception of calcium carbonate containing toothpastes.

Example 4 Head space analysis was carried out on the dicalcium phosphate abrasive containing samples of Example 3, using the procedure described above. The results are shown below. The area under the curve is reported for each of seven components as well as total area under the curves.

Table 4-1 Toothpaste Compositions Containing CMC Binder Sample # 3-1 A 3-1 B 3-1 C 3-1 D Ingredient None RC 591 MCC/CMC/CaC03 MCC/SLS Limonene 3.9 7. 3 Menthone 2.5 2.4 6.5 6.5 Menthyl esters 14.7 12.2 1.8 3.2 Menthol 33.5 19.0 23. 6 32.7 Carvone 23.6 29.7 9.5 8.3 Methyl Salicylate 13.1 Anethole 1. 9 2. 9 1. 4.1. 8 Total 89.4 63.2 46.7 59.8 Table 4-2 Toothpaste Compositions Containing Xanthan Binder Sample # 3-2A 3-2B 3-2C 3-2D Ingredient None RC 591 MCC/CMC/CaCO3 MCC/SLS Limonene 3.7 2.8 Menthone 1.8 6.8 7.0 3.4 Menthyl esters 36.6 2.0 7.5 Menthol 28.2 35.6 44.4 75.7 Carvone 22.4 11.6 9.3 15.1 Methyl Salicylate 6.3 Anethole 1. 3 1. 4 6. 2 Total 96.6 61.1 60.7 110.7

Table 4-3 Toothpaste Compositions Containing TP-329 Binder Sample # 3-3A 3-3B 3-3C 3-3D Ingredient None RC 591 MCC/CMC/CaCO3 MCC/SLS Limonene 5. 0 4. 0 Menthone 2.6 8.6 3.1 3.9 Menthyl esters 40.8 2.1 Menthol 18.6 49.1 34.6 47.3 Carvone 32.5 22.7 6.1 30.4 Methyl Salicylate 5.9 5.0 6.1 Anethole 1. 9 2. 9 12. 4.3. 2 Total 107.3 94.4 56.2 90.9 Table 4-4 Toothpaste Compositions Containing TP-389 Binder Sample # 3-4A 3-4B 3-4C 3-4D Ingredient None RC 591 MCC/CMC/CaCO3 MCC/SLS Limonene 2.9 3.8 Menthone 2.0 3.4 3.5 Menthyl esters 13.8 8.8 10.5 Menthol 26.7 10.2 27.2 31.2 Carvone 24.9 15.1 20.5 24.3 Methyl Salicylate. 16.7 7.5 9.0 Anethole 1. 6 1. 4 Total 85.7 39.1 56.5 83.7 The average total area under the curve for the determinations for each of the co-binders are given in the Table below.

Co-binder Average Area Under the Curve None 94.7 RC-591 64.4 MCC/CMC/CaCO3 55.0 MCC/SLS 87. 2 The shows that a co-binder of colloidal microcrystalline cellulose co- processed with a surfactant has a much smaller effect on the volatile flavor materials than the co-processed colloidal microcrystalline celluloses evaluated.

Examples 5 to 7 These Examples show that colloidal microcrystalline cellulose co- processed with carboxymethyl cellulose and an attriting agent is more effective in reducing stringiness than colloidal microcrystalline cellulose co- processed with carboxymethyl cellulose.

The following toothpaste compositions were prepared.

Chalk Abrasive Containing Toothpaste Compositions In. gredient % % % Glycerin 10.00 10.00 10.00 Sorbitol 17.00 17.00 17.00 CMC 1.00 1.00 1.00 Avicel RC 591 0.00 0.30 0.00 MCC + CaC03 0.00 0.00 0.30 Sodium Saccharin 0.20 0.20 0.20 Sodium Benzoate 0.30 0.30 0.30 Chalk 46.00 46.00 46.00 Flavor 1.00 1. 00 1.00 SLS 2.00 2.00 2.00 Water 22. 50 22. 20 22. 20 Dicalcium Phosphate Abrasive Containing Toothpaste Compositions Ingredient % % % Glycerin 10.00 10.00 10.00 Sorbitol 17.00 17.00 17. 00 CMC 1.00 1.00 1.00 AV) RC 591 0.00 0.30 0.00 MCC + CaC03 0.00 0.00 0.30 Sodium Saccharin 0.20 0.20 0.20 TSPP 0.25 0.25 0.25 SMFP 0.76 0.76 0.76 DCP 50. 00 50.00 50.00 Flavor 1.00 1.00 1.00 SLS 2.00 2.00 2.00 Water 17. 79 17. 49 17. 49

Silica Abrasive Containing Toothpaste Compositions Ingredient % % % Sorbitol 68.00 68.00 68. 00 CMC 1.00 1.00 1.00 AVICELO RC 591 0.00 0.30 0.00 MCC + CaC03 0.00 0.00 0.30 Sodium Saccharin 0.20 0.20 0.20 Sodium Benzoate 0.20 0.20 0.20 ZEODENT 165 7.00 7.00 7.00 ZEODENT@113 11.00 11.00 11.00 Flavor 1.00 1.00 1.00 SLS 2.00 2.00 2.00 Water 9. 60 9. 30 9. 30 The stringiness of the formulation was measured using a texture analyzer. The texture analyzer is fitted with a plunger that moves downward and touches a sample of toothpaste. The plunger remains on the sample for a stipulated time and then starts moving upward bringing with it a string of toothpaste. After the plunger reaches a particular height or distance on its upward ascent, the toothpaste string will break. The test is stopped as soon as the string breaks and the distance traveled, in millimeters, by the plunger is the measure of stringiness. MCC/CMC was AVICELO RC 591 co-processed microcrystalline cellulose.

A 2 gram sample of toothpaste was placed at the center of the lower plate of the texture analyzer. The force of the plunger was set at 200 g, and the pretest speed of the plunger was set at 1 mm/sec. Pretest speed is the speed that the plunger will travel down before starting the test. The sample holding time for the plunger was set at two seconds. This allows the plunger to touch the sample on the holding plate and remain there for two seconds before traveling upward. The post test time was set at 1 mm/sec. This is the speed at which the plunger travels upward. The test was stopped as soon as the string broke and the distance traveled in millimeters by the plunger was measured.

Example 5 Stringiness Reduction for a DCP Containing Toothpaste Co-binder Stringiness Reduction Reduction (mm ! (%) CMC 21. 09---- CMC + MCC/CMC 15. 39 5.70 27% CMC + MCC/CMC/CaCO3 12. 039. 06. 43% Example 6 Stringiness Reduction for a Silica Containing Toothpaste Co-binder Stringiness Reduction Reduction (mm) (% CMC 23. 41---- MCC/CMC 20.33 3.08 13% MCC/CMC/CaCO3 16. 13 7. 28 31% Example 7 Stringiness Reduction for a Calcium Carbonate Containing Toothpaste Co-binder Stringiness Reduction Reduction (mm) (%) CMC 25. 86---- MCC/CMC 18.27 7.59 29% MCC/CMC/CaC03 15. 53 10. 33. 40% Average Stringiness Reduction Co-Binder Stringiness Reduction MCC/CMC 23% MCC/CMC/CaC03 38% For all three abrasives, a much greater reduction in stringiness was observed when colloidal microcrystalline cellulose co-processed with carboxymethyl cellulose and an attriting agent was used as the co-binder than was observed when colloidal microcrystalline cellulose co-processed with carboxymethyl cellulose was used as the co-binder.

Example 8 This example illustrates the use of colloidal microcrystalline cellulose co-processed with a hydrocolloid and an attriting agent in a high moisture toothpaste composition.

A toothpaste composition is prepared as described above containing: 0.7% TP 399; 10.5% sorbitol on an absolute basis; 0.2%

sodium saccharin; 0. 08% methyl paraben; 0.02% propyl paraben; 7.0% ZEODENT (E) 165; 9. 0% ZEODENT) 113; 0. 5% MCC/CMC/CaC03, 1.0% flavor, 2.0% SLS, and 69.0% water. A toothpaste composition that has an initial viscosity of about 120,000 to about 140,000 cps is obtained. The toothpaste composition is stable when stored at 25°C for six months.

Example 9 This example illustrates the use of colloidal microcrystalline cellulose co-processed with a surfactant in a high moisture toothpaste composition.

The procedure of Example 8 is repeated except that MCC/SLS is used in place of the MCC/CMC/CaCO3. A toothpaste composition that has an initial viscosity of about 120,000 to about 140,000 cps is obtained. The toothpaste composition is stable when stored at 25°C for six months.

Example 10 This example illustrates the use of colloidal microcrystalline cellulose co-processed with carrageenan in a high moisture toothpaste composition.

The procedure of Example 8 is repeated except that colloidal microcrystalline cellulose co-processed with carrageenan, such as is disclosed in Tuason, U. S. Pat. No. 6,391, 368, is used in place of the MCC/CMC/CaC03. A toothpaste composition that has an initial viscosity of about 120,000 to about 140,000 cps is obtained. The toothpaste composition is stable when stored at 25°C for six months.

Similar results are obtained when colloidal microcrystalline cellulose co-processed with carrageenan, such as is disclosed in Tuason, WO 03/096976, is used in place of the MCC/CMC/CaCOs.

Example 11 This example illustrates the use of colloidal microcrystalline cellulose co-processed with a hydrocolloid and an attriting agent in a high moisture toothpaste composition.

A toothpaste composition is prepared as described above containing: 0. 7% TP 399; 14. 0% sorbitol on an absolute basis; 0.2% sodium saccharin; 0.20% sodium benzoate; 7.0% ZEODENTO 165; 9.0% ZEODENTO 113; 0.5% MCC/CMC/CaC03, 1. 0% flavor, 2.0% SLS, and 65.5% water. A toothpaste composition that has an initial viscosity of about

150,000 to about 160,000 cps is obtained. The toothpaste composition is stable when stored at 25°C for twelve weeks.

Example 12 This example illustrates the use of colloidal microcrystalline cellulose co-processed with a surfactant in a high moisture toothpaste composition.

The procedure of Example 11 is repeated except that MCC/SLS is used in place of the MCC/CMC/CaCO3. A toothpaste composition that has an initial viscosity of about 150,000 to about 160,000 cps is obtained. The toothpaste composition is stable when stored at 25°C for twelve weeks.

Example 13 This example illustrates the use of colloidal microcrystalline cellulose co-processed with carrageenan in a high moisture toothpaste composition.

The procedure of Example 11 is repeated except that colloidal microcrystalline cellulose co-processed with carrageenan, such as is disclosed in Tuason, U. S. Pat. No. 6,391, 368, is used in place of the MCC/CMC/CaCO3. A toothpaste composition that has an initial viscosity of about 150,000 to about 160,000 cps is obtained. The toothpaste composition is stable when stored at 25°C for twelve weeks.

Similar results are obtained when colloidal microcrystalline cellulose co-processed with carrageenan, such as is disclosed in Tuason, WO 03/096976, is used in place of the MCC/CMC/CaCO3.

Having described the invention, we now claim the following and their equivalents.