Oral care composition

Abstract

A dentifrice composition comprising a rice hull separated silica thickening agent and a mineral silica abrasive, wherein the weight ratio of the rice hull separated silica to the mineral silica abrasive is from 1:1 to 1:12.

Description

Technical Field

[0001] This invention relates to oral care compositions with improved flavor characteristics. Background Technology

[0002] WO08 / 082757 (Huber), WO2007 / 078630 (Huber) and WO 2007 / 078651 (Huber) disclose toothpaste compositions containing rice silica as an abrasive.

[0003] Toothpaste compositions containing silica are well known; however, there is still a need for toothpaste compositions with compositions that enhance flavor properties. Summary of the Invention

[0004] Therefore, the present invention relates to a dental cleaning composition comprising a rice husk-separated silica thickener and a mineral silica abrasive, wherein the weight ratio of the rice husk-separated silica to the mineral silica abrasive is 1:1 to 1:12.

[0005] The present invention also relates to the use of rice husk-derived silica for improving the flavor intensity and / or freshness of dental cleaning compositions.

[0006] Another aspect of the invention is a composition comprising rice husk-derived silica, used in a method for improving the flavor intensity and / or freshness of a dental cleaning agent according to any of the preceding claims. Invention Details Unless otherwise expressly stated in the embodiments, or unless otherwise explicitly stated, all figures indicating the amount of material or reaction conditions, the physical properties of the material and / or its use in this specification may optionally be understood to be modified by the word “approximately”.

[0008] Unless otherwise stated, all quantities are by weight of the composition.

[0009] It should be noted that when specifying any numerical range, any upper limit value can be associated with any specific lower limit value.

[0010] Where a feature is disclosed for a particular aspect of the invention (e.g., a composition of the invention), such disclosure should also be considered applicable to any other aspect of the invention (e.g., a method of the invention) with the necessary modifications.

[0011] Any natural or naturally isolated ingredients mentioned in this application are derived from Europe.

[0012] Unless otherwise expressly stated, for the purposes of this invention, "particle size" refers to the D50 particle size. The D50 particle size of particulate material is a particle diameter in which 50% by weight of the particles have a diameter greater than that diameter, and 50% by weight of the particles have a diameter less than that diameter. For the purposes of this invention, particle size and distribution are measured using, for example, a laser diffraction particle size analyzer manufactured by Malvern.

[0013] The compositions of the present invention are in the form of a dental cleaning agent, preferably toothpaste. This composition is not intended to be swallowed for the purpose of systemic application as a therapeutic agent, but rather applied to the oral cavity for oral treatment and then spat out. Typically, this composition is used in conjunction with a cleaning tool such as a toothbrush, usually by applying it to the bristles of the toothbrush and then brushing the accessible surfaces of the oral cavity.

[0014] The composition is a product intended for oral activity during normal use, not for systemic application or intentional swallowing, but for retention in the oral cavity for a sufficient time to contact substantially all tooth surfaces and / or oral tissues.

[0015] Preferably, the toothpaste is in a squeezeable semi-solid form, such as a cream, paste, or gel (or a mixture thereof).

[0016] A preferred aspect of the invention is a composition comprising rice husk silica, used in a method for improving the flavor of a mineral silica abrasive toothpaste, compared to a nearly identical composition but omitting rice husk silica.

[0017] Silica material isolated from rice husks can be obtained as described in U.S. Patent 6,406,678.

[0018] While the amount of silica in rice husks can vary depending on the geographical region of cultivation and the rice variety, it typically accounts for 13-15% of the dry weight. Most biomaterials, such as rice husks, contain silica almost entirely in a highly desirable amorphous form, but it is bound to the biomaterial matrix by many other impurities, particularly long-chain hydrocarbons such as lignin and cellulose, as well as many inorganic minerals such as calcium, magnesium, and their compounds. Removing silica from rice husks involves the necessary separation of silica from other impurities found in the biomaterial, primarily its hydrocarbons. After removing the hydrocarbons, trace amounts of residual inorganic minerals can be easily and completely removed. The final product is a finely dispersed white powder of high-purity amorphous silica.

[0019] The rice husk-derived silica of this invention is a ready-to-use additive.

[0020] The rice husk silica used in this invention has the additional advantage of being present at the level of a thickening product. Preferably, the level of separated rice husk silica is 0.1 to 12% by weight of the total composition, more preferably 1 to 10.0% by weight.

[0021] For the purposes of this application, the thickened rice silica has an abrasiveness (RDA) of less than 30, preferably a bulk density of less than 100 g / L and a flaxseed oil absorption value of greater than 200 ml / 100 g.

[0022] Preferably, the particle size (D50) of the separated silica from rice husks is 5 to 12 micrometers.

[0023] The compositions of the present invention comprise mineral silica-based abrasives, referred to herein as silica abrasives. Preferred abrasive silica for use in the present invention is silica with a low refractive index. It may be used as the sole abrasive silica, or in combination with small amounts of other abrasive silicas, such as those according to EP 236070. The low refractive index silica used as an abrasive in the present invention is preferably silica with an apparent refractive index (RI) in the range of 1.41 to 1.47, preferably in the range of 1.435 to 1.445, and preferably has a weight average particle size of 5 to 15 µm and a particle size of 10 to 100 μm. 2 / g of BET (nitrogen) surface area and approximately 70-150 cm² 3 Oil absorption per 100 g is required, but triboelectric silica with a lower apparent refractive index can also be used. Typical examples of suitable low-refractive-index triboelectric silica (e.g., with an RI of 1.435 to 1.445) are Tixosil 63 and 73 from Rhone Poulenc; Sident 10 from Degussa; Zeodent 113 from Zeofinn; Zeodent 124 from Evonik; and Sorbosil AC 77 from PQ Corporation (with an RI of about 1.440). The amount of these silicas in the composition is typically 5 to 60% by weight, usually 6 to 40% by weight, and most preferably 7 to 30% by weight.

[0024] Preferably, the purity of the silica separated from the rice husk is 95% by weight, more preferably 98% by weight.

[0025] Thickening silica from mineral sources (i.e. not derived from rice) is preferably present at a level of less than 0.5% by weight, preferably less than 0.1% by weight, of the total composition.

[0026] The weight ratio of rice husk-separated silica to mineral silica in the composition according to the present invention is 1:1 to 1:12, preferably 1:1 to 1:10.

[0027] In addition to the ingredients specified above, the compositions according to the invention typically contain other ingredients to enhance performance and / or consumer acceptance.

[0028] In some embodiments, abrasives such as calcium carbonate, calcium phosphate abrasives such as tricalcium phosphate, hydroxyapatite, or dicalcium phosphate dihydrate or calcium pyrophosphate are used, and / or silica abrasives, sodium metaphosphate, potassium metaphosphate, aluminum silicate, calcined alumina, or other siliceous materials, or combinations thereof. However, in preferred embodiments, these are not present.

[0029] The dental cleaning composition according to the invention may contain sodium bicarbonate at a level of 0.1% to 5% by weight, preferably 0.1% to 1% by weight, of the total composition.

[0030] The compositions according to the invention may contain polyols, such as propylene glycol, xylitol, and lactitol. Glycerol is a preferred polyol, and sorbitol is particularly preferred.

[0031] The compositions of the present invention may contain 0.5 to 5% by weight of an antimicrobial quaternary ammonium material in the total composition. Preferred antimicrobial quaternary ammonium materials are cetylpyridinium chloride (CPC), CPC-clay benzalkonium chloride, tetradecylpyridine chloride (TPC), and N-tetradecyl-4-ethylpyridine chloride (TDEPC). Cetylpyridinium chloride clay complexes are particularly preferred.

[0032] The composition may contain from about 0.10 to about 5% by weight of a natural or synthetic thickener or gelling agent, depending on the selected materials. The proportion of these thickeners in the dental cleaning composition of the present invention forms an extrudable, shape-retaining product that can be squeezed from a tube onto a toothbrush and does not fall between the bristles of the toothbrush, but rather retains its shape substantially thereon. Irish moss, ι-carrageenan, tragacanth gum, polyvinylpyrrolidone, sodium carboxymethyl cellulose, hydroxyethyl cellulose (Natrosol®), xanthan gum, gum arabic, etc., as well as synthetic polymers such as polyacrylates and carboxyvinyl polymers such as Carbopol®; xanthan gum and carrageenan are preferred. The dental cleaning composition according to any of the preceding claims further comprises a polymeric thickener selected from carboxymethyl cellulose, xanthan gum, carrageenan, or mixtures thereof, with carboxymethyl cellulose being particularly preferred.

[0033] Preferably, the weight ratio of the polymeric thickener to rice husk silica is 1:1 to 1:15.

[0034] The compositions according to the invention may contain a polymerization deposition aid. Preferably, the composition contains anhydride polymers, particularly preferably copolymers of maleic anhydride and methyl vinyl ether, wherein the anhydride moiety may be in a partially or completely hydrolyzed or alcoholically hydrolyzed form. Preferred copolymers include Gantrez® polymers, for example: Gantrez S-95: Molecular weight 216,000; Free acid type; Gantrez S-96: Molecular weight 700,000; Free acid type; Gantrez S-97: Molecular weight 1,500,000; Free acid type; and Gantrez MS-955: Molecular weight 1,060,000; calcium / sodium salt type.

[0035] The particularly preferred copolymer of maleic acid and methyl vinyl ether has a molecular weight of 1,000,000 or greater, and the particularly preferred material is Gantrez S-97.

[0036] The compositions according to the invention may contain a teeth whitening agent. The whitening agent preferably contains green and / or blue pigments. In the context of this invention, pigment is generally understood as a shade / material that is insoluble in the relevant medium and at the relevant temperature. This contrasts with soluble dyes. In the context of this invention, "relevant medium" is human saliva, i.e., the liquid medium in which the composition is used, at the oral temperature during brushing, i.e., at most 37°C. As a reasonable approximation, the relevant medium can be considered as water, and the relevant temperature can be considered as 25°C.

[0037] Preferably, the blue pigment is Pigment Blue 15, more preferably Pigment Blue 15:1, 15:2, 15:3, 15:4, 15:5 or 15:6, and most preferably 15:1. The preferred pigment is blue pigment, phthalocyanine blue pigment, CI No. 74160, Blue Covarine.

[0038] The preferred green pigment is phthalocyanine green, and more preferably phthalocyanine green CI-74260.

[0039] Preferably, the total pigment level in the composition is 0.01% to 3% by weight, more preferably 0.02% to 2% by weight.

[0040] If the composition is toothpaste, it can be a biphasic paste in which whitening pigments are present in one phase.

[0041] The compositions according to the invention may contain a water-soluble or slightly water-soluble metal salt source. Preferred are zinc ions, such as zinc chloride, zinc acetate, zinc gluconate, zinc sulfate, zinc fluoride, zinc citrate, zinc lactate, zinc oxide, zinc monoglyceride, zinc tartrate, zinc pyrophosphate, and zinc maleate; also preferred are stannous ions, such as stannous fluoride and stannous chloride.

[0042] The compositions according to the invention may comprise oral care enzyme systems, such as hydrogen peroxide-generating enzyme systems (e.g., oxidoreductase glucose oxidase), amylase, glucanase and / or polysaccharidease (optionally in the presence of compounds that provide zinc ions and / or 8-hydroxyquinoline derivatives), lactoperoxidase, lactoferrin, lysozyme and mixtures thereof.

[0043] The compositions of the present invention may comprise a fluoride source, such as sodium fluoride, stannous fluoride, sodium monofluorophosphate, zinc ammonium fluoride, tin ammonium fluoride, calcium fluoride, cobalt ammonium fluoride, and mixtures thereof. A fluoride ion source may be added to the composition at a level of about 0.001 wt% to about 10 wt%, for example, about 0.003 wt% to about 5 wt%, 0.01 wt% to about 1 wt%, or about 0.05 wt%. In some embodiments, stannous fluoride is present in an amount of 0.1 wt% to 2 wt% (0.1 wt% to 0.6 wt%) of the total composition weight. A fluoride ion source may be added to the composition at a level of about 0.001 wt% to about 10 wt%, for example, about 0.003 wt% to about 5 wt%, 0.01 wt% to about 1 wt%, or about 0.05 wt%. However, it should be understood that the weight of the fluoride salt required to provide an appropriate level of fluoride ions will obviously vary depending on the weight of the counterion in the salt, and this amount can be readily determined by those skilled in the art. In some embodiments, the fluoride source is a fluoride salt (e.g., sodium fluoride (e.g., about 0.32 wt%)) present in an amount of 0.1 wt% to 2 wt% (0.1 wt% to 0.6 wt%) of the total composition weight.

[0044] Some embodiments of the present invention do not contain a fluoride source, that is, the composition contains less than 0.01% by weight of a fluoride source.

[0045] In one embodiment, a preferred class of oral care active ingredients included in the compositions of the present invention comprises an agent for tooth remineralization. In the context of the present invention, the term "remineralization" means the in-situ formation of hydroxyapatite on the teeth.

[0046] A specific example of a suitable tooth remineralizing agent is a mixture of calcium and phosphate sources, which, when delivered to the tooth, generates hydroxyapatite in situ on the tooth.

[0047] Illustrative examples of calcium sources (hereinafter referred to as "remineralized calcium sources") that can be used in this context include, for example, calcium phosphate, calcium gluconate, calcium oxide, calcium lactate, calcium glycerophosphate, calcium carbonate, calcium hydroxide, calcium sulfate, calcium carboxymethyl cellulose, calcium alginate, calcium citrate, calcium silicate, and mixtures thereof. Preferably, the remineralized calcium source is calcium silicate.

[0048] Based on the total weight of the oral care composition, the amount of one or more remineralized calcium sources (e.g., calcium silicate) in the composition of the present invention is typically 1 to 30%, preferably 5 to 20% of the total weight of the remineralized calcium sources.

[0049] Illustrative examples of phosphate source types (hereinafter referred to as "remineralized phosphate sources") that can be used in this context include, for example, sodium dihydrogen phosphate, disodium hydrogen phosphate, sodium pyrophosphate, tetrasodium pyrophosphate, sodium tripolyphosphate, sodium hexametaphosphate, potassium dihydrogen phosphate, trisodium phosphate, tripotassium phosphate, and mixtures thereof. Preferably, the remineralized phosphate source is a mixture of trisodium phosphate and sodium dihydrogen phosphate.

[0050] Based on the total weight of the oral care composition, the amount of one or more remineralized phosphate sources (e.g., trisodium phosphate and sodium dihydrogen phosphate) in the composition of the present invention is typically 2 to 15%, preferably 4 to 10% of the total weight of the remineralized phosphate sources.

[0051] In some embodiments, the oral care composition comprises an effective amount of one or more antimicrobial agents, such as those selected from: halogenated diphenyl ethers (e.g., triclosan), triclosan monophosphate, herbal extracts and essential oils (e.g., rosemary extract, tea extract, magnolia bark extract, thymol, menthol, eucalyptol, geraniol, carvacrol, citral, physalicylic acid, magnolol, ursolic acid, ursolic acid, catechin, methyl salicylate, epigallocatechin gallate, epigallocatechin gallate, gallic acid, miswak extract, sea buckthorn extract), biguanide disinfectants (e.g., chlorhexidine, alexiconidine, or oteninidine), quaternary ammonium compounds (e.g., cetylpyridinium chloride (CPC), CPC-clay benzalkonium chloride, tetradecylpyridine chloride (TPC), N-tetradecyl-4-ethylpyridine chloride (TPC)). DEPC), phenolic disinfectants, hexocide, furanone, bacteriocins, ethyl lauroyl arginine, arginine bicarbonate, camellia extract, flavonoids, flavans, halodiphenyl ethers, creatine, sanguisorbide, povidone-iodine, dimopiperol, salifluor, metal ions (e.g., zinc salts, stannous salts, copper salts, iron salts), propolis and oxygen-providing agents (e.g., hydrogen peroxide, buffered sodium perborate or sodium percarbonate), phthalic acid and its salts, monoperoxyphthalic acid and its salts and esters, ascorbic acid stearate, oleoyl sarcosine, alkyl sulfates, dioctyl sulfosuccinate, salicylaniline, dumefenamic acid bromide, dimopiperol, octopiol and other piperidinyl derivatives, nisin preparations, chlorites; parabens, such as methylparaben or propylparaben, and any mixtures thereof. One or more additional antimicrobial agents or preservatives may optionally be present in the composition in a total amount of about 0.01% by weight to about 0.5% by weight, optionally about 0.05% by weight to about 0.1% by weight, or about 0.3% by weight of the total composition.

[0052] In some embodiments, the oral care composition further comprises at least one flavorant, which may be used, for example, to enhance the flavor of the composition. Any orally acceptable natural or synthetic flavorant may be used, including but not limited to essential oils and various flavoring aldehydes, esters, alcohols and similar materials, tea flavor, vanillin, sage, marjoram, parsley oil, spearmint oil, cinnamon oil, wintergreen oil, peppermint oil, clove oil, bay leaf oil, anise oil, eucalyptus oil, citrus oil, fruit oil, safrole and its extracts, including those derived from lemon, orange, lime, grapefruit, apricot, banana, grape, apple, strawberry, cherry, pineapple, etc.; flavorings derived from legumes and nuts, such as coffee, cocoa, cola, peanut, almond, etc.; and adsorbent and encapsulating flavorings. The term "flavorant" also encompasses ingredients that provide aromatic and / or other oral sensory effects, including cooling or warming effects. These ingredients include, illustratively, menthol, carvone, menthyl acetate, menthyl lactate, camphor, eucalyptus oil, eucalyptol, anethole, eugenol, cinnamon, raspberry ketone, α-ionone, thymol, linalool, benzaldehyde, cinnamaldehyde, N-ethyl-p-menthane-3-carboxamide, N,2,3-trimethyl-2-isopropylbutyramide, 3-(1-menthoxy)-propane-1,2-diol, cinnamaldehyde glyceryl acetal (CGA), menthone glyceryl acetal (MGA), etc. One or more flavoring agents are optionally present in a total amount of about 0.01% to about 5% by weight of the total weight of the composition, for example, about 0.03% to about 2.5% by weight, optionally about 0.05% to about 1.5% by weight, and further optionally about 0.1% to about 0.3% by weight, and in some embodiments in amounts of about 0.01% to about 1% by weight, about 0.05% to about 2%, about 0.1% to about 2.5%, and about 0.1% to about 0.5% in various embodiments.

[0053] In some embodiments, the oral care composition comprises at least one sweetener that can be used, for example, to enhance the flavor of the composition. Sweeteners available herein include dextrose, polydextrose, sucrose, maltose, dextrin, dry invert sugar, mannose, xylose, ribose, fructose, levulose, galactose, corn syrup, partially hydrolyzed starch, hydrogenated starch hydrolysate, ethanol, sorbitol, mannitol, xylitol, maltitol, isomaltitol, aspartame, neotame, saccharin and its salts (e.g., sodium saccharin), sucralose, dipeptide-based strong sweeteners, cyclamate, and dihydrochalcone.

[0054] One or more sweeteners are optionally present in an amount that depends largely on the total amount of one or more particular sweeteners selected, but typically from 0.005% to 5% by weight of the total weight of the composition, optionally from 0.005% to 0.2% by weight, and further optionally from 0.05% to 0.1% by weight of the total weight of the composition.

[0055] In some embodiments, the oral care composition further comprises agents that interfere with or prevent bacterial adhesion, such as ethyl lauroyl arginine (ELA), Solbrol, or chitosan, and plaque dispersants, such as enzymes (papain, glucosyl amylase, etc.).

[0056] A mixture of any of the above materials may also be used.

[0057] The compositions according to the invention contain other ingredients commonly found in the art, such as: Antimicrobial agents, such as chlorhexidine, sanguisorbin extract, metronidazole, quaternary ammonium compounds, such as cetylpyridinium chloride; cetylpyridinium chloride clay complex; biguanides, such as chlorhexidine digluconate, hexetine, oteninidine, alexiconine; and halogenated bisphenol compounds, such as 2,2'-methylenebis-(4-chloro-6-bromophenol); Anti-inflammatory agents, such as ibuprofen, flurbiprofen, aspirin, indomethacin, etc. Anti-caries agents, such as sodium fluoride and stannous fluoride, fluorine, sodium monofluorophosphate, sodium tripolyphosphate and casein; Dental plaque buffers, such as urea, calcium lactate, calcium glycerophosphate, and strontium polyacrylate; Vitamins, such as vitamins A, C, D, B (preferably B3) and E; Plant extracts; Plant-derived antioxidants, such as flavonoids, catechins, polyphenols, and tannins, and mixtures thereof; Desensitizing agents, such as potassium citrate, potassium chloride, potassium tartrate, potassium bicarbonate, potassium oxalate, potassium nitrate, and strontium salts; Anti-tartar agents, such as alkali metal pyrophosphates, hypophosphite-containing polymers, organophosphonates, and phosphoryl citrates; Biomolecules, such as bacteriocins, antibodies, and enzymes; Flavorings, such as peppermint oil and spearmint oil; Protein materials, such as collagen; preservative; Sunscreen; Hyaluronic acid; Amino acids, such as arginine; Colorant; pH adjuster; Sweeteners; Flavoring agents; Pharmaceutically acceptable carriers, such as starch, sucrose, water, or water / alcohol systems; Surfactants, such as anionic, nonionic, cationic, and zwitterionic or amphoteric surfactants; It may also include polymeric compounds that enhance the delivery of active ingredients such as antimicrobial agents; Buffers and salts are used to buffer the pH and ionic strength of the oral care composition; and Other optional components may include bleaching agents, such as peroxides, such as potassium peroxydiphosphate, foaming systems, such as sodium bicarbonate / citric acid systems, color-changing systems, etc.

[0058] In the following non-limiting embodiments, embodiments of the present invention are represented by numbers, and comparative examples are represented by letters. Detailed Implementation

[0059] Example The toothpaste composition was prepared as described in Table 1.

[0060] Table 1

Claims

1. A dental cleaning composition comprising a rice husk-separated silica thickener and a mineral silica abrasive, wherein the weight ratio of the rice husk-separated silica to the mineral silica abrasive is 1:1 to 1:

12.

2. The dental cleaning composition according to claim 1, wherein the weight ratio of the rice husk-separated silica to the silica abrasive is 1:1 to 1:

10.

3. The dental cleaning composition according to any one of the preceding claims, wherein the level of separated silica from the rice husk is 1.0 to 15.0% by weight of the total composition.

4. The dental cleaning composition according to any one of the preceding claims, wherein the mineral silica abrasive has a weight-average particle size of 5 to 15 µm.

5. The dental cleaning composition according to any one of the preceding claims, wherein the level of the mineral silica abrasive is 5.0 to 30% by weight of the total composition.

6. The dental cleaning composition according to any one of the preceding claims, wherein the particle size (D50) of the rice husk separated silica is 5 to 12 micrometers.

7. The dental cleaning composition according to any one of the preceding claims further comprises a polymeric thickener selected from carboxymethyl cellulose, xanthan gum, carrageenan, or mixtures thereof.

8. The dental cleaning composition according to claim 7, wherein the polymeric thickener is carboxymethyl cellulose.

9. The dental cleaning composition according to any one of the preceding claims, wherein the weight ratio of the polymeric thickener to the rice husk silica is 1:1 to 1:

15.

10. The dental cleaning composition according to any one of the preceding claims, further comprising a zinc salt.

11. The dental cleaning composition according to claim 8 or 9, wherein the weight ratio of the polymeric thickener to the rice husk silica is 1:1 to 1:

8.

12. Use of rice husk-separated silica for improving the flavor intensity of a dental cleaning composition according to any one of the preceding claims.

13. Use of rice husk-separated silica for improving the freshness of the dental cleaning composition according to any one of claims 1 to 11.

14. A composition comprising rice husk-derived silica, used in a method for improving the freshness of a dental cleaning agent according to any one of claims 1 to 11.

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