Oral care composition

Abstract

A toothpaste comprising: i) zinc sulfate heptahydrate; ii) glycine; iii) a silica abrasive; iv) greater than 20% by weight of water; wherein the weight ratio of zinc sulfate heptahydrate to glycine is 1: 3 to 2: 1.

Description

Technical Field

[0001] The present invention relates to oral care compositions, in particular toothpaste compositions comprising zinc salts. Background Art

[0002] Zinc salts have been used in some oral care compounds for many years. US Pat. No. 5,470,561 discloses an anti-plaque mouthwash comprising zinc salts and triclosan. The composition may also contain glycine and have a pH of 4 to 8, preferably 5 to 7, with a preferred pH of 6.

[0003] WO0612977 discloses a toothpaste composition containing zinc. The toothpaste contains water, a zinc salt, and a chelating agent for zinc.

[0004] US 5 632 972 discloses a method of minimizing damage to gingival and periodontal tissues by delivering a first component comprising zinc and a second component comprising bicarbonate.

[0005] GB 2 052 978 and EP 0 740 932 disclose oral care compositions comprising zinc-glycine combinations.

[0006] Compositions comprising zinc salts and calcium carbonate-based abrasives are disclosed in US 2009 / 202453 and US 2021 / 059914.

[0007] There remains a need to improve zinc deposition on gingival surfaces. Summary of the Invention

[0008] The present invention relates to a toothpaste comprising:

[0009] i) zinc sulfate heptahydrate;

[0010] ii) glycine;

[0011] iii) 3-50 wt. % of the total composition of a silica abrasive;

[0012] iv) greater than 20% by weight of the total composition of water;

[0013] The weight ratio of zinc sulfate heptahydrate to glycine is 1:1 to 2:3.

[0014] The present invention also relates to a method for cleaning teeth, comprising the step of applying the above composition to the teeth and gums.

[0015] Another aspect of the present invention is the above-described composition for use in a method of cleaning the teeth and gums.

[0016] The present invention also relates to the use of the above composition in the treatment of reducing dental plaque, gum bleeding, gingivitis and oral malodor. Detailed Description of the Invention

[0018] Except in the examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or reaction conditions, physical properties of materials and / or use may optionally be understood as modified by the word "about."

[0019] All amounts are by weight of the composition unless otherwise specified.

[0020] It should be noted that in specifying any numerical range, any upper value can be associated with any particular lower value.

[0021] Where features are disclosed with respect to a particular aspect of the invention (eg, the composition of the invention), such disclosure should also be considered applicable, mutatis mutandis, to any other aspect of the invention (eg, the method of the invention).

[0022] Any ingredients mentioned in this application as natural or of natural origin are of European origin.

[0023] The term "oral care composition" refers to a composition that is delivered to the surfaces of the oral cavity. The composition can be a product that is not intended for systemic administration or intended swallowing during normal use, but rather is intended to remain in the oral cavity for a time sufficient to contact substantially all tooth surfaces and / or oral tissues for oral active purposes.

[0024] Examples of oral compositions include toothpaste or dentifrices, mouthwashes or rinses, powders (e.g., tooth powders), lozenges, mints, pastes, tooth strips or gels (e.g., chewing gum), films, topical oral gels, denture cleansers, and the like.

[0025] The compositions of the present invention are preferably used for cleaning oral surfaces.

[0026] Accordingly, preferred product forms for use in the compositions of the present invention are those suitable for brushing and / or rinsing oral surfaces.

[0027] The compositions of the present invention are in the form of a dentifrice. The term "dentifrice" refers to an oral composition used to clean the surfaces of the oral cavity. Such compositions are not intended to be swallowed for the purpose of systemic administration of a therapeutic agent, but rather are applied to the oral cavity, used to treat the oral cavity, and then expectorated. Typically, such compositions are used in conjunction with a cleaning implement, such as a toothbrush, typically by applying the composition to the bristles of the toothbrush and then brushing the accessible surfaces of the oral cavity.

[0028] Preferably, the dentifrice / toothpaste is in the form of an extrudable semi-solid such as a paste, paste or gel (or a mixture thereof).

[0029] Compositions according to the present invention (eg dentifrices / toothpastes) may typically contain, in addition to the ingredients mentioned above, other ingredients to enhance performance and / or improve consumer acceptability.

[0030] The toothpaste composition according to the present invention comprises zinc sulfate heptahydrate and glycine in a weight ratio of 1:1 to 2:3.

[0031] Preferably, the zinc sulfate heptahydrate is present in an amount of 1 to 3.8 wt %, more preferably 1.5 to 3.5 wt %, most preferably 2 to 3 wt % of the total composition.

[0032] Preferably, the content of glycine is from 1.5 to 4 wt%, more preferably from 2 to 3.5 wt% of the total composition.

[0033] Compositions according to the present invention comprise particulate silica abrasive in an amount of between 3% and 50% by weight of the oral care composition.

[0034] The composition of the present invention comprises a silica-based abrasive. The preferred abrasive silica for use in the present invention is a silica with a low refractive index. It can be used as the sole abrasive silica or in combination with low levels 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 a silica with an apparent refractive index (RI) of 1.41-1.47, preferably 1.435-1.445, preferably having a weight average particle size of 5-15 mm, a particle size of 10-100 m 2 / g BET (nitrogen) surface area and about 70-150 cm 3 The oil absorption rate of the present invention is about 1.000 g / 100 g, but abrasive silicas with a lower apparent refractive index can also be used. Typical examples of suitable low refractive index abrasive silicas (e.g., RI between 1.435 and 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 (RI of about 1.440). The amount of these silicas in the composition is preferably 5-30% by weight, typically 6-20% by weight, of the total composition.

[0035] The composition according to the present invention comprises less than 10 wt% of calcium carbonate abrasive, preferably less than 5 wt%, more preferably less than 1 wt% of the total composition.

[0036] The composition preferably contains an inorganic or natural or synthetic thickener or gelling agent in a proportion of about 0.10 to about 15% by weight, depending on the material selected. These proportions of thickener in the dentifrice composition of the present invention allow for the formation of an extrudable shape-retaining product that can be squeezed from a tube onto a toothbrush and does not settle between the bristles of the toothbrush, but rather substantially retains its shape thereon. Suitable thickeners or gelling agents that can be used in the practice of the present invention include inorganic thickening silica, such as amorphous silica available from Huber Corporation under the trade name Zeodent 165, Irish moss, iota carrageenan, gum tragacanth, and polyvinyl pyrrolidone.

[0037] Other suitable binders and thickeners may be present and include sodium carboxymethylcellulose, hydroxyethylcellulose Xanthan gum, gum arabic, etc., as well as synthetic polymers such as polyacrylates, and carboxyvinyl polymers such as Sodium carboxymethylcellulose is particularly preferred.

[0038] The composition according to the present invention preferably comprises a surfactant, such as anionic, nonionic, cationic and zwitterionic or amphoteric surfactants. Preferably, the composition comprises an anionic surfactant, more preferably sodium lauryl sulfate. Preferably, the content of anionic surfactant is greater than 0.1% by weight of the total composition, preferably from 0.5 to 2.5% by weight of the total composition, more preferably from 1 to 2% by weight.

[0039] The composition according to the present invention may contain a polymeric deposition aid. Preferably, the composition comprises an anhydride polymer, particularly preferably a copolymer of maleic anhydride and methyl vinyl ether, wherein the anhydride portion may be in a partially or completely hydrolyzed or alcoholized form. Preferred copolymers include Gantrez(R) polymers, for example:

[0040] Gantrez S-95: molecular weight 216,000; free acid;

[0041] Gantrez S-96: molecular weight 700,000; free acid;

[0042] Gantrez S-97: molecular weight 1,500,000; free acid; and

[0043] Gantrez MS-955: molecular weight 1,060,000; calcium / sodium salt.

[0044] A particularly preferred copolymer of maleic acid and methyl vinyl ether has a molecular weight of 1,000,000 or greater, with Gantrez S-97 being a particularly preferred material.

[0045] The composition according to the present invention may contain a tooth whitening agent. The whitening agent preferably comprises a green and / or blue pigment. In the context of the present invention, a pigment is generally understood to be a tint / material that is insoluble in the relevant medium at the relevant temperature. This is in contrast to a soluble dye. In the context of the present invention, the "relevant medium" is human saliva, i.e., the liquid medium when the composition is used during tooth brushing at oral temperature, i.e., at most 37°C. As a reasonable approximation, the relevant medium can be considered to be water, and the relevant temperature is 25°C.

[0046] 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, most preferably 15: 1. A preferred pigment is a blue pigment which is Phthalocyanine Blue pigment, CI No. 74160, Covarine Blue.

[0047] A preferred green pigment is phthalocyanine green, preferably phthalocyanine green CI-74260.

[0048] Preferably, the total content of pigments in the composition is 0.01-3 wt%, more preferably 0.02-2 wt%.

[0049] Toothpaste may be a dual phase paste, in which the whitening pigment is present in one phase.

[0050] The composition according to the invention may comprise an oral care enzyme system, such as an enzyme system that generates hydrogen peroxide (e.g. the oxidoreductase glucose oxidase), amyloglucosidase, glucanase and / or mutagenase (optionally in the presence of a compound that provides zinc ions and / or an 8-hydroxyquinoline derivative), lactoperoxidase, lactoferrin, lysozyme and mixtures thereof.

[0051] Composition of the present invention can comprise fluoride source, such as sodium fluoride, stannous fluoride, sodium monofluorophosphate, zinc ammonium fluoride, stannic ammonium fluoride, calcium fluoride, cobalt ammonium fluoride and their mixture.Fluoride ion source can be with about 0.001 % by weight to about 10 % by weight, for example, the level of about 0.003 % by weight to about 5 % by weight, 0.01 % by weight to about 1 % by weight or about 0.05 % by weight is added in the composition.In some embodiments, stannous fluoride exists with the amount of 0.1 % by weight to 2 % by weight (0.1 % by weight to 0.6 % by weight) of total composition weight.Fluoride ion source can be with about 0.001 % by weight to about 10 % by weight, for example, the level of about 0.003 % by weight to about 5 % by weight, 0.01 % by weight to about 1 % by weight or about 0.05 % by weight is added in the composition.Yet it should be understood that the weight of the fluoride salt of the fluoride ion providing appropriate content can obviously change based on the weight of counter ion in the salt, and those skilled in the art can easily determine such amount. In some embodiments, the fluoride source is a fluoride salt present in an amount of 0.1 wt% to 2 wt% (0.1 wt%-0.6 wt%) (eg, sodium fluoride (eg, about 0.32 wt%)) based on the weight of the total composition.

[0052] Some embodiments of the present invention are free of a fluoride source, ie, the composition comprises less than 0.01 wt. % of a fluoride source.

[0053] In one embodiment, a preferred class of oral care actives for inclusion in the compositions of the present invention comprises agents for tooth remineralization.In the context of the present invention, the term "remineralization" refers to the in situ generation of hydroxyapatite on teeth.

[0054] A specific example of a suitable agent for tooth remineralization is a mixture of a calcium source and a phosphate source which, when delivered to the tooth, results in the in situ formation of hydroxyapatite on the tooth.

[0055] Illustrative examples of the types of calcium sources that can be used in the present application (hereinafter referred to as "remineralized calcium sources") include, for example, calcium phosphate, calcium gluconate, calcium oxide, calcium lactate, calcium glycerophosphate, calcium carbonate, calcium hydroxide, calcium sulfate, carboxymethylcellulose calcium, calcium alginate, calcium citrate, calcium silicate, and mixtures thereof. Preferably, the remineralized calcium source is calcium silicate.

[0056] The amount of remineralized calcium source (eg calcium silicate) in the composition of the present invention is typically 1 to 30%, preferably 5 to 20% by weight of the total weight of the remineralized calcium source, based on the total weight of the oral care composition.

[0057] Illustrative examples of the types of phosphate sources that can be used in the present application (hereinafter referred to as "remineralized phosphate sources") 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.

[0058] The amount of remineralizing phosphate source (eg, trisodium phosphate and sodium dihydrogen phosphate) in the composition of the present invention is typically 2 to 15%, preferably 4 to 10% by weight of the total weight of the remineralizing phosphate source, based on the total weight of the oral care composition.

[0059] In some embodiments, the oral care composition comprises an effective amount of one or more antibacterial agents, for example, an antibacterial agent selected from the group consisting of 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, hinokitiol, magnolol, ursolic acid, ursic acid, catechol, methyl salicylate, epigallocatechin gallate, epigallocatechin, gallic acid, jasmine extract, sea buckthorn extract), biguanide disinfectants (e.g., chlorhexidine, alexidine, or octenidine), quaternary ammonium compounds (e.g., cetylpyridinium chloride (CPC), CPC-clay benzalkonium chloride, tetradecylpyridinium chloride (TPC), N-tetradecyl-4-ethylpyridinium chloride (TDEPC)), phenolic disinfectants, hyclate benzoyl peroxide, ... One or more additional antimicrobial agents or preservatives may optionally be present in the composition in a total amount of about 0.01 wt % to about 0.5 wt %, optionally about 0.05 wt % to about 0.1 wt % or about 0.3 wt %, based on the total weight of the composition.

[0060] In some embodiments, the oral care composition also includes at least one flavoring agent, which can be used for example to enhance the taste of the composition. Any oral acceptable natural or synthetic flavoring agent can be used, including but not limited to essential oils and various flavoring aldehydes, esters, alcohols and similar materials, tea flavoring agents, vanillin, sage, marjoram, parsley oil, spearmint oil, cinnamon oil, wintergreen oil, peppermint oil, clove oil, bay oil, anise oil, eucalyptus oil, citrus oil, fruit oil, sassafras and essence, including those derived from lemon, orange, lime, grapefruit, apricot, banana, grape, apple, strawberry, cherry, pineapple, etc., beans and nuts derived flavoring agent, such as coffee, cocoa, cola nut (cola), peanut, almond, etc., adsorption and encapsulated flavoring agent, etc. Flavoring agent herein also includes providing fragrance and / or other sensory effects in the mouth, including ingredients of cooling or warming effects. These ingredients illustratively include menthol, carvone, menthyl acetate, menthyl lactate, camphor, eucalyptus oil, eucalyptol, anethole, eugenol, cinnamon, oxanone, α-ionone, thymol, linalool, benzaldehyde, cinnamaldehyde, N-ethyl-p-menthane-3-carboxamide, N,2,3-trimethyl-2-isopropylbutanamide, 3-(1-mentholoxy)-propane-1,2-diol, cinnamaldehyde glycerol acetal (CGA), menthone glycerol acetal (MGA), and the like. One or more flavoring agents are optionally present in a total amount of about 0.01% to about 5% by weight, e.g., about 0.03% to about 2.5%, optionally about 0.05% to about 1.5%, further optionally about 0.1% to about 0.3%, and in some embodiments about 0.01% to about 1%, about 0.05 to about 2%, about 0.1% to about 2.5%, and about 0.1 to about 0.5%, based on the total weight of the composition.

[0061] In some embodiments, the oral care composition comprises at least one sweetener, which can be used, for example, to enhance the taste of the composition. Sweeteners useful in the present application include dextrose, polydextrose, sucrose, maltose, dextrin, dried invert sugar, mannose, xylose, ribose, fructose, levulose, galactose, corn syrup, partially hydrolyzed starch, hydrogenated starch hydrolysate, ethanol, sorbitol, mannitol, xylitol, maltitol, isomalt, aspartame, neotame, saccharin and its salts (e.g., saccharin sodium), sucralose, strong sweeteners based on dipeptides, cyclamates, dihydrochalcone, glycerol, propylene glycol, polyethylene glycol.

[0062] One or more sweeteners are optionally present in a total amount that depends strongly on the particular sweetener selected, but is 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.

[0063] In some embodiments, the oral care composition further comprises agents that interfere with or prevent bacterial attachment, such as ethyl lauroyl arginate (ELA), Solbrol, or chitosan, and plaque dispersants such as enzymes (papain, glucoamylase, etc.).

[0064] Mixtures of any of the above materials may also be used.

[0065] The composition according to the present invention may contain other ingredients commonly used in the art, such as:

[0066] Antimicrobial agents such as chlorhexidine, sanguinarine extract, metronidazole, quaternary ammonium compounds such as cetylpyridinium chloride; cetylpyridinium chloride clay complex biguanides such as chlorhexidine digluconate, hexetidine, octenidine, alexidine; and halogenated bisphenol compounds such as 2,2'methylenebis-(4-chloro-6-bromophenol);

[0067] Anti-inflammatory agents, such as ibuprofen, flurbiprofen, aspirin, indomethacin, etc.;

[0068] anticaries agents such as sodium and stannous fluoride, amine fluoride, sodium monofluorophosphate, sodium metaphosphate, and casein;

[0069] plaque buffers, such as urea, calcium lactate, calcium glycerophosphate, and strontium polyacrylate;

[0070] Vitamins, such as vitamins A, C, D, B (preferably B3), and E;

[0071] Plant extracts;

[0072] plant-derived antioxidants such as flavonoids, catechins, polyphenols, and tannin compounds and mixtures thereof;

[0073] desensitizing agents, such as potassium citrate, potassium chloride, potassium tartrate, potassium bicarbonate, potassium oxalate, potassium nitrate, and strontium salts;

[0074] anticalculus agents, such as alkali metal pyrophosphates, hypophosphite-containing polymers, organic phosphonates, and phosphocitrates;

[0075] Biomolecules, such as bacteriocins, antibodies, enzymes, etc.;

[0076] flavorings, such as peppermint and spearmint oils;

[0077] proteinaceous materials, such as collagen;

[0078] preservative;

[0079] sunscreen;

[0080] Hyaluronic acid;

[0081] amino acids, such as arginine;

[0082] colorants;

[0083] pH adjusters;

[0084] sweeteners;

[0085] Mouthfeel agents;

[0086] Pharmaceutically acceptable carriers, such as starch, sucrose, water or water / alcohol systems;

[0087] Humectants, such as glycerin, sorbitol, propylene glycol, xylitol, lactitol, etc.;

[0088] Polymeric compounds that can enhance the delivery of active ingredients such as antimicrobial agents may also be included;

[0089] Buffering agents and salts to buffer the pH and ionic strength of the oral care composition; and

[0090] Other optional ingredients that may be included are, for example, bleaching agents such as peroxy compounds, eg potassium peroxydiphosphate, effervescent systems such as sodium bicarbonate / citric acid systems, color change systems, and the like.

[0091] The invention will now be illustrated by the following non-limiting examples. Examples according to the invention are illustrated by numbers and comparative examples are illustrated by letters. DETAILED DESCRIPTION

[0092] Example

[0093] In vitro skin discs (rehydrated) were coated with a pellicle (immersed in irradiated saliva). They were treated with a 1:2 slurry of toothpaste and Millipore water (1 minute contact time) and then rinsed with water. The discs were digested in nitric acid and zinc content was measured by ICP-MS (inductively coupled plasma mass spectrometry).

[0094] Element Example 1 weight % Example A weight % water 27.47 7.56 sorbitol 45 58 Zinc sulfate heptahydrate 2.72 2.72 Glycine 3.08 3.08 Sodium fluoride 0.32 0.32 Hydrated silica abrasive (Abrasivity) 8 10.6 Hydrated silica thickening 9 8.25 Sodium carboxymethyl cellulose 0.9 0.7 PAS-Oral Care Grade (SLS) 1.7 2.7 trace ingredients to 100 to 100 <![CDATA[Zinc deposition amount g / m 2 > 0.25 (SD 0.0058) 0.16 (SD 0.0033)

Claims

1. A toothpaste comprising: i) zinc sulfate heptahydrate; ii) glycine; iii) 3-50 wt. % of a silica abrasive based on the total composition; iv) greater than 20% by weight of the total composition of water; The weight ratio of the zinc sulfate heptahydrate to glycine is 1:1 to 2:

3.

2. The toothpaste composition according to claim 1, wherein the content of zinc sulfate heptahydrate is 1.5 to 3.5 wt%, preferably 2 to 3 wt%, of the total composition.

3. A toothpaste composition according to any one of the preceding claims, wherein the glycine content is from 1.5 to 4 wt%, preferably from 2 to 3.5 wt% of the total composition.

4. A toothpaste composition according to any one of the preceding claims, wherein the silicon dioxide is present in an amount of 5 to 30 wt%, preferably 10 to 20 wt% of the total composition.

5. A toothpaste composition according to any preceding claim, further comprising a surfactant, preferably sodium lauryl sulfate.

6. A toothpaste composition according to any one of the preceding claims, wherein the total level of surfactants is from 0.5 to 2.5 wt%, more preferably from 1 to 2 wt% of the total composition.

7. A toothpaste composition according to any preceding claim comprising less than 10% by weight of the total composition of calcium carbonate abrasive.

8. A toothpaste composition according to any one of the preceding claims, further comprising sodium carboxymethylcellulose.

9. A method of cleaning teeth comprising the step of applying to the teeth and gums a composition according to any one of the preceding claims.

10. A composition according to any one of claims 1 to 8 for use in a method of cleaning teeth and gums.

11. A composition according to any one of claims 1 to 8 for use in the treatment of reducing dental plaque, gum bleeding, gingivitis and oral malodour.