阅读说明：本技术 口腔护理组合物 (Oral care compositions ) 是由 普贾·库尔卡尼 费林 苏曼·乔普拉 哈勒娜·施特罗特曼 唐赛德 于 2020-03-24 设计创作，主要内容包括：本文描述了包含金属硅酸盐(例如,硅酸钾)的口腔护理组合物；以及其制备和使用方法。(Described herein are oral care compositions comprising metal silicates (e.g., potassium silicate); and methods of making and using the same.)

1. An oral care composition, comprising:

a first metal silicate; and

an orally acceptable carrier;

wherein the first metal silicate comprises a silicate of a monovalent or divalent metal ion.

2. The oral care composition according to claim 1, wherein the first metal silicate comprises a silicate of a monovalent metal ion.

3. The oral care composition according to claim 1 or claim 2, wherein the first metal silicate comprises a silicate of a monovalent metal ion selected from Na + and K +.

4. The oral care composition of any preceding claim, wherein the first metal silicate comprises a silicate of K +.

5. The oral care composition of any preceding claim, further comprising:

core-shell silica particles comprising;

a second metal silicate; and

a silica particle comprising a core having a surface;

wherein the surface of the silica core is etched with the second metal silicate; and

wherein the second metal silicate comprises a metal ion.

6. The oral care composition according to claim 5, wherein the second metal silicate comprises a silicate of a monovalent or polyvalent metal ion.

7. The oral care composition of claim 6, wherein the polyvalent metal ion is selected from the group consisting of: ca2+, Mg2+, Zn2+, Sn2+, Sr2+, Al3+, Zr4+, Ti4+, Fe3+, Fe2+, Mo2+, Co2+, Ni2+, Mn2+, Cu2+, Pd2+, Mo2+, Ru2 +; and combinations of two or more thereof.

8. The oral care composition according to claim 6 or claim 7, wherein the polyvalent metal ion is a divalent metal ion selected from the group consisting of Ca2+, Mg2+, Zn2+, Sn2+, Sr2+, Fe2+, Mo2+, Co2+, Ni2+, Mn2+, Cu2+, Pd2+, Mo2+, and Ru2 +.

9. The oral care composition according to any one of claims 6 to 8, wherein the polyvalent metal ion is selected from the group consisting of Zn2+ and Sn2 +.

10. The oral care composition according to any one of claims 6 to 9, wherein the second metal silicate further comprises a monovalent metal ion.

11. The oral care composition according to claim 10, wherein the monovalent metal ion is selected from Na + and K +.

12. The oral care composition according to claim 11, wherein the monovalent metal ion is K +.

13. The oral care composition according to any one of claims 5 to 12, wherein the silica is selected from the group consisting of: precipitating silicon dioxide; fumed silica; heat treated precipitated silica and fused silica.

14. The oral care composition according to any one of claims 5 to 13, wherein the core-shell silica particles comprise a plurality of metal silicate layers.

15. The oral care composition according to claim 14, comprising from about 2 to about 100, from about 2 to about 40, from about 2 to about 12, or from about 12 to about 40 metal silicate layers.

16. The oral care composition according to any one of claims 6 to 15, wherein the second metal silicate comprising divalent metal ions comprises at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, or at least about 90% by weight of the total metal silicates of the core-shell silica particles.

17. The oral care composition according to any one of claims 5 to 16, wherein the core-shell silica particles have a d50 of from about 5nm to about 50 μ ι η.

18. The oral care composition of any preceding claim, wherein the oral care composition is in a form selected from: a paste; gelling; a prophylactic agent; a dissolvable strip; a tablet; an adhesive tape; dental floss; and mouthwashes or rinses.

19. The oral care composition according to any preceding claim wherein the orally acceptable carrier comprises an anticaries agent, a desensitizing agent, a viscosity modifier, a surfactant, an emulsifier, a foam modifier, a pH modifier, an mouthfeel agent, a sweetener, a flavoring agent, a coloring agent, a preservative, an amino acid, an antioxidant, an anticalculus agent, a fluoride ion source, a stannous ion source, a thickener, a brightener, or a combination of two or more thereof.

20. The oral care composition of any preceding claim, wherein the oral care composition has a pH of from about 6 to about less than 10.

21. The oral care composition of any preceding claim, wherein the oral care composition has a pH of from about 8 to about 9.

22. The oral care composition of claim 20 or claim 21, wherein the oral care composition further comprises a gel matrix.

23. The oral care composition of claim 22, wherein the first metal silicate and the core-shell silica particles are embedded within the gel matrix.

24. The oral care composition according to claim 22 or claim 23, wherein the gel matrix has a viscosity of from about 10,000cps to about 100,000 cps.

25. The oral care composition according to any one of claims 22 to 24, wherein the gel matrix controls delivery of the first metal silicate and/or the core-shell silica particles.

26. The oral care composition according to any foregoing claim, wherein the first metal silicate is present in an amount of from about 0.1 wt.% to about 20 wt.%.

27. The oral care composition according to any foregoing claim, wherein the first metal silicate is present in an amount of from about 0.5 wt.% to about 4 wt.%.

28. The oral care composition according to any foregoing claim, wherein the first metal silicate is present in an amount of from about 0.75 wt.% to about 3 wt.%.

29. The oral care composition according to any foregoing claim, wherein the first metal silicate is present in an amount of from about 1 weight% to about 2 weight%.

30. The oral care composition according to any foregoing claim, wherein the first metal silicate is present in an amount of from about 1.5 wt.% to about 1.75 wt.%.

31. The oral care composition according to any foregoing claim, wherein the first metal silicate is present in an amount of about 1.6 wt.%.

32. A method for:

a) reducing extrinsic stains on mammalian teeth;

b) whitening mammalian teeth; and

c) removing extrinsic stains from mammalian teeth;

the method comprises the following steps:

applying a composition according to any preceding claim to an oral surface of a mammal in need thereof.

33. The method of claim 32, wherein the mammal is a human.

34. Use of a composition according to any one of claims 1 to 31 in the manufacture of an oral care composition for:

a) reducing extrinsic stains on mammalian teeth;

b) whitening mammalian teeth; and

c) removing extrinsic stains from mammalian teeth.

35. The use of claim 34, wherein the mammal is a human.

Background

Some individuals are not satisfied with the color of their teeth. Therefore, there is a great need in the market for whiter teeth; and one way to achieve whiter teeth is to use a tooth whitening product. There are a range of tooth whitening products including toothpastes, gels, trays, strips and professional treatments. Different treatment types are preferred depending on the perceived needs of the consumer. More and more consumers are showing a need for a mild whitening regimen for tooth enamel; and is moving away from more extreme and expensive professional treatments. Instead, they seek a safe, easy, inexpensive and effective choice, for example in toothpaste.

The color of a human tooth comes from the combined color of enamel and dentin. Enamel is a translucent material that covers a person's teeth and thins out over time. Over time, the natural color of the teeth becomes more yellow because the teeth become thinner as the stain accumulates. These stains may come from a variety of sources, such as drugs, diet, and lifestyle choices. There are two types of tooth stains-extrinsic and intrinsic; and a different mode of action is required to target each type of stain. Extrinsic stains are typically removed by a combination of the mechanical action of the abrasive system in the toothpaste and the brushing action of the toothbrush; while intrinsic stains are attacked with bleaching agents such as hydrogen peroxide, which can penetrate the enamel surface.

Certain markets do not allow the use of hydrogen peroxide and other oxidizing agents in their dentifrices; consumers in these regions, however, still need products that meet their whitening needs. One way to provide additional stain removal benefits without the use of oxidizing agents is to utilize novel abrasive systems and additives that enhance the efficacy of those abrasive systems.

Embodiments of the present invention are directed to these and other objects.

Disclosure of Invention

In some embodiments, the present invention provides an oral care composition comprising: a first metal silicate; and an orally acceptable carrier; wherein the first metal silicate comprises a silicate of a monovalent or divalent metal ion. In other embodiments, the invention further comprises: core-shell silica particles comprising; a second metal silicate; and silica particles comprising a core having a surface; wherein the surface of the silica core is etched with the second metal silicate; and wherein the second metal silicate comprises a metal ion.

Additional embodiments provide an oral care composition comprising: an orally acceptable carrier; a first metal silicate comprising a silicate of a monovalent metal ion; and a gel matrix; wherein the oral care composition has a pH of from about 8 to about 10.

Other embodiments provide methods for: a) reducing extrinsic stains on mammalian teeth; b) whitening mammalian teeth; c) reduction or prevention of tartar; and/or d) removing extrinsic stains from mammalian teeth; the method comprises the following steps: applying a composition according to any preceding claim to an oral surface of a mammal in need thereof.

Further embodiments provide a use of any of the compositions described herein for the manufacture of a medicament for: a) reducing extrinsic stains on mammalian teeth; b) whitening mammalian teeth; c) reduction or prevention of tartar; and/or d) removing extrinsic stains from the teeth of the mammal.

Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.

Detailed Description

The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

As used throughout, ranges are used as a shorthand for describing each value within the range as well as for describing sub-ranges within the range. Any value within the range can be selected as the upper limit of the range. Any value within the range can be selected as the lower limit of the range.

In addition, all references, books, patents, and patent application publications cited herein are hereby incorporated by reference in their entirety. In the event of a conflict between a definition in the present disclosure and a definition in a cited reference, book, patent, and patent application publication, the present disclosure controls.

Unless otherwise specified, reference to ambient or room temperature refers to a temperature range of 20-25 ℃.

Unless otherwise specified, all percentages and amounts expressed herein and elsewhere in this specification are to be understood as referring to weight percentages based on the total weight of the composition.

As used herein, the phrase "and/or", exemplified by option a and/or option B, encompasses (i) option a; (ii) option B; and (iii) individual embodiments of option a plus option B.

It is to be understood that embodiments described herein in the "comprising" language also provide other similar embodiments described in terms of "consisting of and/or" consisting essentially of.

While aspects or embodiments of the invention are described in terms of a Markush group or other alternative grouping scheme, the invention encompasses not only the entire group as listed in its entirety, but also all possible sub-groups of each member of the group and the main group, as well as the main group lacking one or more of the group members. The present invention also contemplates the explicit exclusion of one or more of any group member in the claimed invention.

All combinations of the various elements described herein are within the scope of the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

In some embodiments, the present invention provides an oral care composition comprising: a first metal silicate; and an orally acceptable carrier; wherein the first metal silicate comprises a silicate of a monovalent or divalent metal ion. In some embodiments, the first metal silicate comprises a silicate of a monovalent metal ion. In other embodiments, the first metal silicate consists essentially of monovalent metal ions. In other embodiments, the first metal silicate consists of a monovalent metal ion and a silicone or derivative thereof. In some embodiments, the first metal silicate comprises a silicate of a monovalent metal ion selected from Na + and K +. In some embodiments, the monovalent metal ion comprises Na +. In some embodiments, the monovalent metal ion comprises K +.

In some embodiments, the oral care composition further comprises: core-shell silica particles comprising; a second metal silicate; and silica particles comprising a core having a surface; wherein the surface of the silicon dioxide core is etched with a second metal silicate; and wherein the second metal silicate comprises metal ions. As used herein, the term "etched" means that the surface of the silicon dioxide core dissolves and metal silicate forms adjacent to the silicon dioxide core. A method for preparing core-shell silica particles includes etching raw silica to form a metal silicate. The second metal silicate layer is not formed on top of the original surface of the silicon dioxide core. In contrast, the reaction of the silica particles with the base results in a reduction in the diameter of the original silica particles, and a second metal silicate layer is formed on top of the surface of the etched silica particles having the reduced diameter.

In some embodiments, the second metal silicate comprises a silicate of a monovalent or polyvalent metal ion. In other embodiments, the polyvalent metal ion is selected from: ca2+, Mg2+, Zn2+, Sn2+, Sr2+, Al3+, Zr4+, Ti4+, Fe3+, Fe2+, Mo2+, Co2+, Ni2+, Mn2+, Cu2+, Pd2+, Mo2+, Ru2 +; and combinations of two or more thereof. In other embodiments, the polyvalent metal ion is a divalent metal ion selected from the group consisting of Ca2+, Mg2+, Zn2+, Sn2+, Sr2+, Fe2+, Mo2+, Co2+, Ni2+, Mn2+, Cu2+, Pd2+, Mo2+, and Ru2 +. In certain embodiments, the multivalent metal ion is selected from Zn2+ and Sn2 +.

In some embodiments, the second metal silicate further comprises a monovalent metal ion. In some embodiments, the monovalent metal ion of the second metal silicate is selected from Na + and K +. Additional embodiments provide compositions wherein the second metal silicate comprises a monovalent metal ion that is K +.

In certain embodiments, the silica is selected from: precipitating silicon dioxide; fumed silica; heat treated precipitated silica; and fused silica.

In some embodiments, the silica is fumed silica. Fumed silica (sometimes referred to as fumed silica or silica fume) is a very fine particulate or colloidal form of silica. It was prepared by combusting SiCl4 in an oxygen-rich hydrocarbon flame to produce a "smoke" of SiO 2. The silica particles fuse with each other to form branched, three-dimensional chain-like aggregates:

SiCl4+2H2+O2→SiO2+4HCl。

in some embodiments, the silica is precipitated silica. Amorphous silica (silica gel) is produced by acidification of sodium silicate solution. The initially formed gelatinous precipitate was subsequently washed and then dehydrated to yield colorless microporous silica. The ideal equation relating trisilicate and sulfuric acid is shown:

Na2Si3O7+H2SO4→3SiO2+Na2SO4+H2O

in most silicas, the Si atoms exhibit tetrahedral coordination, with 4 oxygen atoms surrounding the central Si atom. The most common example is found in the quartz crystalline form of silica SiO 2. In each of the most thermodynamically stable crystalline forms of silica, on average, all 4 vertices (or oxygen atoms) of the SiO4 tetrahedra are shared with other tetrahedra, resulting in the pure formula: SiO 2. In addition to the amorphous form, SiO2 also has a number of different crystalline forms (polymorphs). With the exception of steshovite (steshovite) and fibrous silica, all crystalline forms involve tetrahedral SiO4 units connected together by a common apex in different arrangements.

Precipitated silicas include, but are not limited to114 and165 (precipitated silica particles manufactured by j.m. huber-synthetic amorphous silica), manufactured by w.r.grace783. Produced by Ineos (PQ Co.)AC-43。

The silica may be a fumed silica, such as Aerosil 200 produced by Evonik.

In another embodiment, the silica is a fused silica, including but not limited to those produced by Cabot corporationHP-60, produced by C-E Minerals10 and44css, and Spheron P1500, produced by Japan Glass Co.

The oral care composition of any preceding claim, wherein the core-shell particle comprises a plurality of metal silicate layers. In some embodiments, the core-shell silica particles comprise from about 2 to about 100, from about 2 to about 40, from about 2 to about 12, or from about 12 to about 40 metal silicate layers. In other embodiments, the core-shell silica particles may comprise 2,4, 16, 32, 36, or 64 monolayers.

In some embodiments, the second metal silicate comprises znsio3.xh2o, wherein x is 0 to 10.

In one embodiment, the surface of the silica core is the outer surface of the silica core. Additionally or alternatively, the surface of the silica core may be an inner surface of the silica core.

The silicate of the second metal ion may constitute at least 30 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt%, 80 wt% or 90 wt% of the total metal silicate of the CSS particle. Preferably, the silicate of the second metal ion comprises at least 90 wt% of the total metal silicate of the CSS particle.

In some embodiments, the outer 10nm depth of the core-shell silica particles may comprise 0.1 to 10 wt% of the metal silicate. In some embodiments, the outer 10nm depth of the core-shell silica particles has the general formula: wherein O is oxygen in the form of a silicate; n is a monovalent metal ion; m is divalent zinc ion; u is trivalent metal ion; v is a tetravalent metal ion; p, o, n, m, u, v, h and q are atomic percentages of each component; and the total charge of each core-shell silica particle is zero.

The atomic percentage of each component other than H + is generally determined by chemical analysis using Electron Spectroscopy (ESCA). In one example, using ESCA data, the following elements are detected:

O56.81Si26.52O*7.35Na3.18Zn4.65Cl1.49

by setting the total charge to zero by adding H + and water, we conclude that the outer 10nm depth of each particle may have the following composition in one embodiment:

(SiO2)26.52[O*7.35Na3.18Zn4.65Cl1.49H3.73]·3.77H2O

the d (0.5) value of the particles is generally from 5nm to 50 μm.

The particles may have a d (0.5) value of 26 μm to 40 μm. Particles having a d (0.5) value in this range are generally opaque. Translucent particles are those particles that allow light to pass through but not allow the image to be seen through the particles. This is in contrast to clear compositions, which allow light to pass through and images to be seen through the composition. Methods for determining particle size are well known in the art. For example, particle size can be determined using light scattering methods, such as using Mastersizer 2000, Hydro 2000S, Malvern Instruments Limited.

The particles may have a d (0.5) value of 18 μm to 25 μm. Particles having a d (0.5) value in this range are generally opaque. The particles may have a d (0.5) value of 10 μm to 15 μm. Particles having a d (0.5) value in this range are generally opaque. In another embodiment, the d (0.5) value of the CSS particles may be from 5 μm to 15 μm.

In another embodiment, the d (0.5) value of the CSS particles may be from 2.5 μm to 4.5 μm. In another embodiment, the d (0.5) value of the CSS particles may be from 5nm to 20 nm. In another embodiment, the d (0.5) value of the CSS particles may be from 10nm to 15 nm. In another embodiment, the particles may have a d (0.5) value of 5nm to 12 nm.

The d (0.5) or d50 of the particle is the diameter (usually in microns) that divides the distribution into half the population above and half below the diameter. Dv50 (or dv0.5) is the median value for the volume distribution, Dn50 for the number distribution and Ds50 for the surface distribution. In the context of the present invention, d (0.5) will be used to refer to the median particle size of the volume distribution (dv0.5).

The d (0.1) value of the particles is the diameter that divides the distribution into 10% of the population below the diameter and 90% above the diameter.

The d (0.9) value of the particles is the diameter that divides the distribution into 90% of the population below the diameter and 10% above the diameter.

The values used to describe the distribution width of the particle size distribution are span:

span (d (0.9) -d (0.1))/d (0.5)

The span of the core-shell silica particles according to the invention is generally from 1.5 to 3.

In a preferred embodiment, the CSS has a d (0.1) of 10 to 13 μm, a d (0.5) of 30 to 33 μm and a d (0.9) of 61 to 64 μm.

In another preferred embodiment, the CSS has a d (0.1) of 6 to 9 μm, a d (0.5) of 18 to 21 μm and a d (0.9) of 41 to 45 μm.

In a further preferred embodiment, the CSS has a d (0.1) of 3 to 5 μm, a d (0.5) of 11 to 14 μm and a d (0.9) of 33 to 36 μm.

In a preferred embodiment, the d (0.5) value of the CSS particles is smaller than the average diameter of human dentinal tubules. This allows CSS particles to enter the dentinal tubules, which may be exposed when the protective enamel layer is damaged. In a human tooth, the average diameter of the dentinal tubules near the dentin-enamel junction is 0.9 μm, the average diameter of the middle segment of the dentinal tubules is about 1.2 μm, and near the pulp, the average diameter is about 2.5 μm.

In another embodiment of the invention, the silica source is selected to produce CSS particles that fit in the dentinal tubules (e.g.,200-fumed silica (synthetic amorphous silica), d (0.5) is 0.012 μm). In another embodiment of the invention, the d (0.5) value of the CSS particles is less than 0.9. mu.m. In yet another embodiment of the invention, the d (0.5) of the CSS particles is in the range of 0.010 μm to less than 0.9 μm. In another embodiment of the present invention, CSS particles of the present invention may also plug, block, or plug pores in the enamel.

The core-shell silica particles of the present invention have unexpectedly high surface charge densities and ion exchange capacities. In one embodiment, the core-shell silica particles have a surface charge density of 0.5 to 4.5meq/g silica. In one embodiment, the core-shell silica particles have a surface charge density of 2 to 3meq/g silica. In one embodiment, the core-shell silica particles have a surface charge density of from 2.45 to 2.55meq/g of silica.

In one embodiment, the core-shell silica particles have a charge or ion exchange capacity of 0.05 to 0.1C/cm2 surface area. In one embodiment, the core-shell silica particles have a charge or ion exchange capacity of 0.085 to 0.095C/cm2 surface area. In one embodiment, the core-shell silica particles have a charge or ion exchange capacity of 0.089C/cm2 surface area.

In one embodiment of the Zn-CSS particle, the amount of zinc adsorbed to the surface monolayer of the particle is less than 50% of the maximum ion exchange capacity of the particle for divalent ions. In one embodiment, the amount of zinc adsorbed to the surface monolayer of the particle is 30-35% of the maximum ion exchange capacity of the particle for divalent ions. In one embodiment, the amount of zinc adsorbed to the surface monolayer of the particle is 33% of the maximum ion exchange capacity of the particle for divalent ions.

In another aspect, the present invention provides an oral care composition comprising any of the core-shell silica particles described herein.

In one embodiment, the composition comprises from 0.01% to 0.5% by weight of soluble metal ions. The soluble metal ion may be a zinc ion. One of the advantages of the CSS composition of the invention is that the CSS particles complex with metal ions, resulting in a lower concentration of free metal ions in solution. High concentrations of free metal ions, such as zinc ions, can present disadvantages, particularly for oral care compositions. For example, high concentrations of soluble zinc ions can result in poor mouthfeel characteristics of the composition.

In some embodiments, the oral care composition further comprises an orally acceptable carrier.

In one embodiment of the composition, the core-shell silica particles comprise a range selected from the group consisting of 0.1 wt% to 35 wt% by weight of the composition. In another embodiment of the composition, the CSS particles are present in an amount of 0.1% to 1%. In another embodiment of the composition, the CSS particles are present in an amount of 0.5 wt.% to 20 wt.%, and in another embodiment of the composition, the CSS particles are present in an amount of 1 wt.% to 10 wt.%.

In one embodiment, the metal salt is present in 0.01 to 3.0% by weight of the composition. In one embodiment, the metal salt is present in 0.01 to 1.5% by weight of the composition. In one embodiment, the metal salt is present at 0.01 to 1.0 wt%. In one embodiment, the metal salt is present at 0.1 to 0.5 wt%. In one embodiment, the metal salt is present at 0.1%. In one embodiment, the metal salt is present at 1 wt% or 2 wt%. In one embodiment, the metal salt is ZnCl2 in an amount from 0.5 to 2 weight percent of the composition.

In another embodiment of the present invention, the composition may take any dosage form suitable for oral administration. In one embodiment, the composition is a solid, paste, gel, or liquid.

Illustrative examples of these forms include, but are not limited to, a dentifrice (e.g., toothpaste, dental gel, dental cream or tooth powder), mouthwash, rinse or oral spray; oral slurry or liquid dentifrice; chewing gum or other confectionery; buccal tablets; dental floss or dental tape; a prophylactic paste or powder; single or multi-layer oral films or gel strips (e.g., dental or respiratory strips), preferably using biodegradable or orally consumable films or gels; a functional film or gel sheet or functional millimeter, micron or nanoparticle; film-forming compositions (e.g., film-forming dentifrices, dental coatings) comprising a pre-gel or pre-polymer; a tooth hardening agent; or a coating on an oral appliance (e.g., orthodontic appliance or implant).

For solid dentifrices, such as toothpastes, the amount of water in the composition is selected from the amounts consisting of: less than 80 wt.%, less than 75 wt.%, less than 70 wt.%, less than 65 wt.%, less than 60 wt.%, less than 55 wt.%, less than 50 wt.%, less than 45 wt.%, less than 40 wt.%, less than 35 wt.%, less than 30 wt.%, less than 25 wt.%, less than 20 wt.%, less than 15 wt.%, less than 10 wt.%, less than 5 wt.%, less than 1 wt.%. In each of these amounts, the lower range of the amount of water is 0% or no more than 0.1% water.

In one embodiment of the oral care composition, the composition further comprises an anti-malodor agent. In one embodiment, the additional anti-malodor compounds are known odor control agents. In addition, other metal-containing compounds (such as copper, stannous, bismuth, strontium) and saliva stimulating agents (saliva) or other ingredients that increase saliva flow for odor removalAlso suitable for use in the compositions described herein. Certain strong citrus flavors, odor absorbing complexes (which entrain or adsorb malodorous molecules are also suitable for use in the claimed compositions, for example,malodorous molecules, such as mercaptans, sulfides and amines, can be encapsulated in their structure as disclosed, for example, in U.S. patent No.6,664,254. Suitable odor control actives also include, but are not limited to, enzymes that can interrupt the process of generating odors. For example, odor blocking enzymes, such as arginine deiminase, may be effectively formulated in the compositions of the present invention. In addition, odor control can be achieved using molecules effective in inhibiting the production of malodorous molecules by bacteria, such as agents that interfere with the bacterial enzymes cysteine desulfhydrase and/or methionine gamma-lyase. Odor control actives suitable for use in blocking odors or as odor blockers include, but are not limited to, agents that act by oxidizing or otherwise chemically reacting with malodor molecules, including peroxides, perchlorates, and reactive molecules with activated double bonds.

The carrier may include, but is not limited to, water or other aqueous solvent systems.

The orally acceptable carrier can also comprise a humectant. Possible humectants are ethanol; polyols including, but not limited to, glycerol, glycols, inositol, maltitol, mannitol, sorbitol, xylitol, propylene glycol, polypropylene glycol (PPG), polyethylene glycol (PEG), and mixtures thereof; or sugars including, but not limited to, fructose, glucose, sucrose, and mixtures of sugars (e.g., honey).

The oral care composition may also comprise an antibacterial agent that is not a core-shell silica particle as described herein. The antibacterial agent can be triclosan (5-chloro-2- (2, 4-dichlorophenoxy) phenol); 8-hydroxyquinoline and salts thereof; zinc and stannous ion sources such as zinc citrate, zinc sulfate, zinc glycinate, sodium zinc citrate, stannous fluoride, stannous monofluorophosphate and stannous pyrophosphate; copper (II) compounds such as copper (II) chloride, copper (II) fluoride, copper (II) sulfate and copper (II) hydroxide; phthalic acid and salts thereof, such as magnesium monopotassium phthalate (magnesium monopersulfate); sanguinarine; quaternary ammonium compounds such as alkylpyridinium chlorides (e.g., cetylpyridinium chloride (CPC), combinations of CPC with zinc and/or enzymes, tetradecylpyridinium chloride, and N-tetradecyl-4-ethylpyridinium chloride); biguanides such as chlorhexidine digluconate, hexetidine (hexetidine), octenidine (octenidine), alexidine (alexidine); halogenated bisphenol compounds such as 2,2' methylenebis- (4-chloro-6-bromophenol); benzalkonium chloride; salicylanilide; domiphen bromide (domiphen bromide); iodine; sulfonamides; bis-biguanides; a phenolic resin; piperidino derivatives such as delmopinol and octapinol; a magnolia extract; thymol; eugenol; menthol; geraniol; carvacrol; citral; eucalyptol; catechol; 4-allylcatechol; hexylresorcinol; methyl salicylate; antibiotics such as wolgermycin (augmentin), amoxicillin (amoxicillin), tetracycline (tetracyline), doxycycline (doxycline), minocycline (minocycline), metronidazole (metronidazole), neomycin (neomycin), kanamycin (kanamycin), and clindamycin (clindamycin); or mixtures thereof.

In some embodiments, the antibacterial agent is present at a concentration selected from the group consisting of 0.001 to 3 weight%, 0.05 to 2 weight%, and 0.075 to 1.5 weight%.

Alternatively, no additional antibacterial agent is present in addition to the core-shell silica particles of the present invention.

In some embodiments, the oral care composition can further comprise an anticaries agent, a desensitizing agent, a viscosity modifying agent, a diluent, a surfactant, an emulsifier, a foam modulator, a pH modifying agent, an abrasive, an mouthfeel agent, a sweetener, a flavoring agent, a coloring agent, a preservative, an amino acid, an antioxidant, an anticalculus agent, a fluoride ion source, a thickening agent, an active agent for preventing or treating a condition or disorder of hard or soft tissue of the oral cavity, an adhesive agent, a whitening agent, and combinations thereof. It will be appreciated that while the general attributes of each of the above categories of materials may differ, there may be some common attributes and any given material may serve multiple purposes within two or more of these categories of materials. Preferably, the carrier is selected to be compatible with the other ingredients of the composition.

Some embodiments of the invention optionally comprise amino acids. Suitable amino acids include, but are not limited to, arginine, cysteine, leucine, isoleucine, lysine, alanine, asparagine, aspartic acid, phenylalanine, glutamate, glutamic acid, threonine, glutamine, tryptophan, glycine, valine, proline, serine, tyrosine, and histidine, and combinations of two or more thereof. Amino acids may include the R and L forms and their salt forms. The amino acids (and salt forms thereof) may also include acid esters and/or fatty amide derivatives of the amino acids (e.g., Ethyl Lauroyl Arginine Hydrochloride (ELAH)).

One embodiment of the composition optionally comprises an antioxidant. Any orally acceptable antioxidant can be used, including Butylated Hydroxyanisole (BHA), Butylated Hydroxytoluene (BHT), vitamin a, carotenoids, vitamin E, flavonoids, polyphenols, ascorbic acid, herbal antioxidants, chlorophyll, melatonin, and mixtures thereof.

One embodiment of the composition optionally comprises an anticalculus (tartar control) agent. Suitable anticalculus agents include, but are not limited to, phosphates and polyphosphates (e.g. pyrophosphates), polyaminopropanesulfonic Acid (AMPS), hexametaphosphates, zinc citrate trihydrate, polypeptides, polyolefin sulfonates, polyolefin phosphates, bisphosphonates. The anticalculus agent is present from about 0.1% to about 30%. The oral composition may comprise a mixture of different anticalculus agents. In a preferred embodiment, tetrasodium pyrophosphate (TSPP) and Sodium Tripolyphosphate (STPP) are used. The anticalculus agent comprises TSPP at about 1-2% and STPP at about 7% to about 10%.

One embodiment of the composition optionally comprises at least one orally acceptable fluoride ion source. Any fluoride ion source known or to be developed in the art may be used. Suitable fluoride ion sources include fluoride, stannous fluoride, sodium fluoride, potassium fluoride, amine fluoride, ammonium fluoride, stannous monofluorophosphate, sodium monofluorophosphate, potassium monofluorophosphate, amine monofluorophosphate, ammonium monofluorophosphate, stannous fluorosilicate, sodium fluorosilicate, potassium fluorosilicate, amine fluorosilicate, ammonium fluorosilicate, and mixtures thereof. The one or more fluoride ion releasing compounds are optionally present in an amount to provide a total of about 100 to about 20,000ppm, about 200 to about 5,000ppm, or about 500 to about 2,500ppm fluoride ions.

One embodiment of the composition optionally comprises various dentifrice ingredients to adjust the rheology and mouthfeel of the composition, such as surfactants, thickening or gelling agents, and the like.

One embodiment of the composition optionally comprises stannous ions or a stannous ion source. Suitable stannous ion sources include, but are not limited to, stannous fluoride, other stannous halides (such as stannous chloride dihydrate), stannous pyrophosphate, organic stannous carboxylates (such as stannous formate, acetate, gluconate, lactate, tartrate, oxalate, malonate, and citrate), stannous glyoxylate, and the like. One or more stannous ion sources are optionally and illustratively present in a total amount of from about 0.01% to about 10%, for example from about 0.1% to about 7% or from about 1% to about 5%.

One embodiment of the composition optionally comprises a surfactant (surface active agent/surfactant). Suitable surfactants include, but are not limited to, water soluble C8-C20 alkyl sulfates, sulfonated monoglycerides of C8-C20 fatty acids, sarcosinates, taurates, sodium lauryl sulfate, sodium cocoyl monoglyceride sulfonates, sodium lauryl sarcosinate, sodium lauryl isethionate, sodium laureth carboxylate and sodium dodecylbenzenesulfonate, and cocamidopropyl betaine.

One embodiment of the composition optionally comprises a thickening agent. Any orally acceptable thickening agent can be used, including, but not limited to: carbomers, also known as carboxyvinyl polymers; carrageenans also known as Irish moss (Irish moss) and more specifically carrageenan (iota-carrageenan); high molecular weight polyethylene glycols (e.g. polyethylene glycol)Available from Dow Chemical Company); fiberCellulose polymers such as hydroxyethyl cellulose, carboxymethyl cellulose (CMC) and salts thereof, e.g. sodium CMC; natural gums such as karaya, xanthan, gum arabic, and gum tragacanth; colloidal magnesium aluminum silicate; and colloidal and/or fumed silica and mixtures thereof. One or more thickeners are optionally present in a total amount of about 0.1% to about 55%, for example about 1% to about 50% or about 5% to about 35%.

One embodiment of the composition optionally comprises flavoring agents, sweetening agents, coloring agents, foam modulators, mouth feel agents, and other additives that may be included in the composition additively, if desired.

One embodiment of the composition optionally comprises one or more additional active agents operable to prevent or treat a condition or disorder of the hard or soft tissue of the oral cavity, prevent or treat a physiological disorder or condition, or provide a cosmetic benefit. Examples of such other active ingredients include sialagogues or saliva stimulants, antiplaque agents, anti-inflammatory agents, and/or desensitizing agents.

Adhesion enhancing agents may also be added to the oral care composition including, but not limited to, waxes (including beeswax), mineral oil, plastigels (blends of mineral oil and polyethylene), petrolatum, white petrolatum, shellac, versagel (blends of liquid paraffin, butylene/ethylene/styrene hydrogenated copolymer), polyethylene waxes, microcrystalline waxes, polyisobutylene, polyvinylpyrrolidone/vinyl acetate copolymers, and insoluble polyacrylate copolymers.

Liquid hydrophilic polymers including polyethylene glycol, ethylene oxide nonionic polymers having the general formula: HOCH2(CH2OCH2) n1CH2OH, wherein n1 represents the average number of oxyethylene groups. Polyethylene glycols available from Dow Chemical are named by numbers such as 200, 300, 400, 600, 2000, which represent the approximate average molecular weight of the polymer, and nonionic block copolymers of ethylene oxide and propylene oxide having the formula: HO (C2H4O) a1(C3H6O) b1(C2H4O) C1H. The block copolymer (relative to a1, b1, and c1) is preferably selected such that the ethylene oxide component comprises from about 65% to about 75% by weight of the copolymer molecules and the average molecular weight of the copolymer is from about 2,000 to about 15,000, wherein the copolymer is present in the liquid tooth whitening composition at the concentration that renders the composition liquid at room temperature.

Particularly desirable block copolymers for use in the practice of the present invention are commercially available from BASF and are known under the designation Pluraflo L1220(PEG/PPG 116/66) with an average molecular weight of about 9,800. The hydrophilic poly (ethylene oxide) block averages about 65% by weight of the polymer.

Synthetic anionic polycarboxylates may also be used in the oral compositions of the present invention as efficacy enhancers for any antibacterial, antitartar or other active agent in the dentifrice composition. The anionic polycarboxylates are generally employed in the form of their free acids or preferably partially or more preferably fully neutralized water soluble alkali metal (e.g., potassium and preferably sodium) or ammonium salts. Preferably a 1:4 to 4:1 copolymer of maleic anhydride or acid with another polymerizable ethylenically unsaturated monomer, preferably methyl vinyl ether/maleic anhydride having a molecular weight (M.W.) of about 30,000 to about 1,800,000, most preferably about 30,000 to about 700,000. Examples of such copolymers are available from the GAF company under the trade name GAF(methyl vinyl ether/maleic anhydride) is commercially available, e.g., AN 139(M.W.500,000), AN 119(M.W.250,000); pharmaceutical grades S-97(m.w.700,000), AN 169(m.w.1,200,000-1,800,000) and AN 179(m.w. greater than 1,800,000); of these, the preferred copolymer is pharmaceutical grade S-97(M.W.700,000).

When present, the anionic polycarboxylate is employed in an amount effective to achieve the desired enhancement of the efficacy of any antibacterial, antitartar or other active agent in the oral composition. Typically, the anionic polycarboxylate is present in the oral composition at about 0.05 wt.% to about 4 wt.%, preferably about 0.5 wt.% to about 2.5 wt.%.

The adhesion enhancing agents employed in the compositions of the various embodiments of the present invention are present in an amount of from about 0% to about 20% by weight. Preferably, the adhesion enhancer is present in an amount of about 2 to about 15 weight percent.

One embodiment of the composition optionally comprises a whitening agent including, but not limited to, peroxy compounds (such as hydrogen peroxide), peroxides of alkali and alkaline earth metals, organic peroxy compounds, peroxy acids, pharmaceutically acceptable salts thereof, and mixtures thereof. Peroxides of alkali and alkaline earth metals include lithium peroxide, potassium peroxide, sodium peroxide, magnesium peroxide, calcium peroxide, barium peroxide, and mixtures thereof. Organic peroxy compounds include urea peroxide (also known as urea hydrogen peroxide), glyceryl hydroperoxide, alkyl hydroperoxides, dialkyl peroxides, alkyl peroxy acids, peroxy esters, diacyl peroxides, benzoyl peroxide, and monoperoxyphthalate, and mixtures thereof. Peroxy acids and salts thereof include organic peroxy acids such as alkyl peroxy acids, and monoperoxyphthalate and mixtures thereof, and inorganic peroxy acid salts such as persulfates, dipersulfates, percarbonates, perphosphates, perborates and persilicates of alkali and alkaline earth metals such as lithium, potassium, sodium, magnesium, calcium and barium, and mixtures thereof. In various embodiments, the peroxy compound comprises hydrogen peroxide, carbamide peroxide, sodium percarbonate, and mixtures thereof.

In some embodiments, a non-peroxide whitening agent may be provided. Whitening agents useful herein include non-peroxy compounds such as chlorine dioxide, chlorite, and hypochlorite. Chlorites and hypochlorites include those of alkali and alkaline earth metals such as lithium, potassium, sodium, magnesium, calcium and barium. Non-peroxide whitening agents also include colorants (such as titanium dioxide and hydroxyapatite), pigments, or dyes. In some embodiments, the whitening agent is separate from the aqueous carrier. In some embodiments, the whitening agent is separated from the aqueous carrier by an encapsulated whitening agent.

In one embodiment of the composition, the composition comprises about 65% to 99.9% of the carrier and further comprises ingredients, i.e., one or more of: anticaries agents, desensitizing agents, viscosity modifiers, diluents, surfactants, emulsifiers, foam modulators, pH modifying agents, abrasives, mouth feel agents, sweeteners, flavorants, colorants, preservatives, amino acids, antioxidants, anticalculus agents, fluoride ion sources, thickeners, agents for preventing or treating conditions or disorders of hard or soft tissues of the oral cavity, whitening agents, and combinations thereof. In another embodiment of the composition, the composition comprises about 80% to 99.5% of the carrier and further comprising ingredients. In another embodiment of the composition, the composition comprises about 90% to 99% of the carrier and further comprising ingredients.

The description of the optional ingredients above is also intended to include any combination of ingredients.

In some embodiments, these core-shell silica particles described herein can be prepared according to the methods described in US 2016/0338920 or US 2016/0338919, the contents of which are incorporated herein in their entirety.

In one embodiment, the silica used may be any abrasive silica. The silica may be selected from the group consisting of precipitated silica, fumed silica, and fused silica.

Precipitated silicas include, but are not limited to114 and165 (precipitated silica particles manufactured by J.M. Huber-chemical name: synthetic amorphous silica), manufactured by W.R. Grace783. Produced by Ineos (PQ Co.)AC-43。

The silica may be a fumed silica, such as Aerosil 200 produced by Evonik.

In another embodiment, the silica is a fused silica, including but not limited to, those disclosed by CabotProduced byHP-60, produced by C-E Minerals10 and44css, and Spheron P1500, produced by Japan Glass Co.

Suitable silicas for use in the present invention also include colloidal silicas (thickening silicas) such as aerogels Syloid 244 and 266 (available from w.r.grace), Aerosil (available from DeGussa Co.), and fumed silica (available from Cabot corporation) sold under the trade name Cab-O-Sil. Tixosil 333 and Tixosil 43B (available from Rhodia Ltda.), Zeodent 165 (available from j.m.

Other suitable silicas for use in the present invention include silica abrasives, which in turn include silica gels and precipitated amorphous silicas. These silicas are colloidal particles/particulates having an average particle size ranging from about 3 microns to about 12 microns, and more preferably between about 5 to about 10 microns and a pH ranging from 4 to 10, preferably 6 to 9, when measured as a 5 wt% slurry.

An illustrative silica abrasive suitable for use in the practice of the present invention is sold under the trade name Sylodent XWA by Davison Chemical Division, w.r.grace & co., Baltimore, md.21203. Sylodent 650XWA, a silica hydrogel, was composed of colloidal silica particles having a water content of 29% by weight, averaging from about 7 to about 10 microns in diameter.

Other types of silica abrasives suitable for use in the present invention include precipitated silicas having an average particle size of up to about 20 microns, such as Zeodent 115 sold by j.m. huber Chemicals Division, Havre de Grace, md.21078; or Sylodent 783 sold by Davison Chemical Division, w.r.grace & Company.

An average depth of 1 to 15nm of silica may be removed from the surface of the silica particles to form silica cores, and metal silicates are formed on top of the silica cores. The average depth of silica removed generally increases with increasing weight ratio of alkali to silica particle. The d (0.5) of the silica core can be 1 to 15nm smaller than the d (0.5) of the silica particles of the starting material. The d (0.5) of the silica core may be about 2nm less than the d (0.5) of the silica particles of the starting material. The d (0.5) particle size of the silica core may be about 6nm smaller than the d (0.5) of the silica particles of the starting material. The particle size percentage of rigid silica particles, such as fumed silica, is reduced more than porous silica particles, such as high cleaning silica. For example, for fumed silica, the percent reduction in particle size (d (0.5)) may be about 15%, while for porous high-cleaning silica, the percent reduction in particle size (d (0.5)) may be about 0.06%.

The formation of the core-shell silica particles of the present invention described above can be achieved by manipulating the amount of the base used, the amount of the humectant used, the amount of the metal salt used, and varying the reaction temperature.

In one embodiment, the endpoint of the process occurs when the d (0.5) value of the core-shell silica particles formed by the process is at least 5% greater in diameter than the d (0.5) value of the silica (SiO2) starting material. In another embodiment, the core-shell silica particles have a diameter that is 5% to 10% greater than the average particle diameter of the silica starting material.

The core-shell silica particles formed may contain 0.0 to 0.5 wt% soluble metal ions. The soluble metal ion is preferably a soluble zinc ion. As discussed above, lower concentrations of soluble metal ions, i.e., lower concentrations of free metal ions, such as zinc ions, that can form complexes with CSS can be used to prepare oral care compositions with improved mouthfeel characteristics.

The formation of core-shell particles can also be monitored by measuring the electrical conductivity of the reaction mixture. The endpoint of the process occurs when the conductivity of the reaction mixture decreases by at least 250 microsiemens/centimeter (μ S/cm) because the charge is transferred from the highly mobile ion (NaOH) to the much less mobile silica surface (mobility ≈ 0). In yet another embodiment, the endpoint of the process occurs when the conductivity of the reaction mixture is reduced by 250-. Typically, core-shell silica particles are formed when the conductivity of the reaction mixture is reduced by at least 2 milliSiemens per centimeter (mS/cm). Typically, core-shell silica particles are formed when the conductivity of the reaction mixture is reduced by at least 5 mS/cm.

In some embodiments, the second metal silicate comprising divalent metal ions comprises at least about 30 wt.%, at least about 40 wt.%, at least about 50 wt.%, at least about 60 wt.%, at least about 70 wt.%, at least about 80 wt.%, or at least about 90 wt.% of the total metal silicates of the core-shell silica particles.

In some embodiments, the core-shell silica particles have a d50 of from about 5nm to about 50 μm.

In other embodiments, the oral care composition has a pH of from about 7.0 to about less than 10.0. In some embodiments, the oral care composition has a pH of from about 7.7 to about 9. In certain embodiments, the oral care composition has a pH of about 7.0, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 8.0, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9.0, 9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9, or 10.0.

In some embodiments, the oral care composition site further comprises a gel matrix. In some embodiments, the first metal silicate and the core-shell silica particles are embedded within the gel matrix. In other embodiments, the gel matrix has a viscosity of about 50,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 1,400,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 1,300,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 1,200,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 1,100,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 1,000,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 900,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 800,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 700,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 600,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 500,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 400,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 100,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 90,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 80,000 cps. In some embodiments, the gel matrix has a viscosity of about 50,000cps to about 70,000 cps. In some embodiments, the gel matrix has a viscosity of about 55,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 60,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 65,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 70,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 75,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 80,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 85,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 90,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 95,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 100,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 150,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 200,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 250,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 300,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 350,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 400,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 450,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 500,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 550,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 600,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 650,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 700,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 750,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 800,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 850,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 900,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 950,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 1,000,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 1,050,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 1,100,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 1,150,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 1,200,000cps to about 1,500,000 cps. In some embodiments, the gel matrix has a viscosity of about 1,250,000cps to about 1,500,000 cps. The gel matrix has a viscosity of about 600,000cps to about 1,500,000.

In some embodiments, the gel matrix controls the delivery of the first metal silicate and/or core-shell silica particles to the tooth surface. In some embodiments, the gel matrix controls the delivery of the first metal silicate and/or core-shell silica particles.

In some embodiments, the first metal silicate is present in an amount from about 0.1% to about 20% by weight of the oral care composition. In some others, the first metal silicate is present in an amount from about 0.1% to about 15% by weight of the oral care composition. In some embodiments, the first metal silicate is present in an amount from about 0.1% to about 10% by weight of the oral care composition. In other embodiments, the first metal silicate is present in an amount from about 0.1% to about 7.5% by weight of the oral care composition. In certain embodiments, the first metal silicate is present in an amount from about 0.1 wt.% to about 4 wt.%. In other embodiments, the first metal silicate is present in an amount from about 0.15 wt.% to about 3 wt.%. Additional embodiments provide oral care compositions wherein the first metal silicate is present in an amount from about 0.2 wt.% to about 2 wt.%. Still other embodiments provide oral care compositions wherein the first metal silicate is present in an amount from about 0.25 wt.% to about 1.5 wt.%. In some embodiments, the first metal silicate is present in an amount from about 0.5 wt.% to about 1.25 wt.%. In other embodiments, the first metal silicate is present in an amount from about 0.55 wt.% to about 1.15 wt.%.

In some embodiments, the first metal silicate is present in an amount from about 0.5 wt.% to about 4 wt.%. In other embodiments, the first metal silicate is present in an amount from about 0.75 wt.% to about 3 wt.%. In certain embodiments, the first metal silicate is present in an amount from about 1 wt.% to about 2 wt.%. Still other embodiments provide oral care compositions wherein the first metal silicate is present in an amount from about 1.5 weight% to about 1.75 weight%. Additional embodiments provide oral care compositions wherein the first metal silicate is present in an amount of about 1.6 weight percent.

Further embodiments provide methods for: a) reducing extrinsic stains on mammalian teeth; b) whitening mammalian teeth; and c) removing extrinsic stains from the teeth of the mammal; the method comprises the following steps: applying a composition according to any preceding claim to an oral surface of a mammal in need thereof.

Other embodiments provide for the use of any of the compositions described herein for the manufacture of an oral care composition for: a) reducing extrinsic stains on mammalian teeth; b) whitening mammalian teeth; and c) removing extrinsic stains from the teeth of the mammal. In some embodiments, the mammal is a human.

In another aspect, the present invention provides a method of reducing or eliminating malodor in the oral cavity of a patient in need thereof comprising applying to the oral surfaces of the patient an oral care composition as defined above.

In some embodiments, mammals include, but are not limited to, humans and animals (e.g., dogs, cats, horses, cattle, sheep, llamas, etc.).

Embodiments of the invention are further described in the following examples. These examples are illustrative only and do not limit the scope of the invention in any way as described and claimed.

Examples

Example 1

The in vitro whitening efficacy of the exemplary compositions of the invention and the comparative compositions were tested by a brush test.

Artificially stained bovine enamel specimens were brushed with a 1:1 silica toothpaste artificial saliva slurry for 15 minutes. The teeth were rinsed thoroughly and the CieLab measurements (L a b) were recorded with a handheld spectrophotometer. Bovine enamel with an L value between 58 and 64 was used for the study.

Four bovine enamel specimens were installed per tray and three trays were used per test unit. A 1:1 test toothpaste artificial saliva slurry was prepared for each test composition. Bovine enamel specimens were brushed for 2 minutes at 120 strokes/min. The teeth were rinsed with DI water and evaluated for L a b values with a spectrophotometer. The brushing was repeated 14 times (corresponding to 1 week of use of the product).

The recorded values of la b were used to calculate the whitening index (W). W describes how close the measured color is to true white in combination with the L, a and b values. It is calculated according to the following equation.

W*＝(a2+b2+(L*-100)2)1/2

The data described in table 1 below reports the change in W (Δ W) after treatment.

TABLE 1

Sample (I)	HCS％	Potassium silicate%	ΔW*
				1	19.7	1.437	-2.50
2	19.7	1.60	-4.54
				3	19.7	3.07	-3.47

The data described in table 1 (above) shows the concentration ranges for potassium silicate to enhance the stain removal capability of High Cleaning Silica (HCS).

Example 2

Further studies were conducted to understand the effect of pH on performance.

As shown by the data described in table 2 (below), pH has an unexpected effect on stain removal ability.

TABLE 2

The data described in table 2 (above) shows that pH has an unexpected effect on the ability of potassium silicate to enhance stain removal capability of compositions comprising high cleaning silica.

Example 3

A study was conducted to demonstrate that the exemplary compositions of the present invention can meet performance standards from a manufacturing standpoint. A composition containing 0.457% potassium silicate at pH 8.0 was applied to half of the SS 316 sample. The sample was allowed to dry at room temperature for about 24 hours. After about 24 hours, the sample was placed in a beaker containing hot water. The hot water was agitated using a stir bar. The test specimens were then evaluated after about 20 minutes using visually perceptible cleaning criteria. The results of this study show that the exemplary compositions of the present invention pass the criteria set by the study protocol.

Example 4

Table 3 below describes several exemplary compositions of the present invention.

TABLE 3

As will be appreciated by those skilled in the art, numerous variations and modifications can be made to the embodiments described herein without departing from the spirit of the invention. All such variations are intended to fall within the scope of the appended claims.