Structures and compositions increasing stability peroxide actives stability

【0001】

This application is a partial continuation of US Patent Application No. 09 / 605,774 filed June 28, 2000; and a partial continuation of US Patent Application No. 09 / 605,220 filed June 28, 2000. The application, now U.S. Pat. No. 5,894,017, is a partial continuation of U.S. Patent Application No. 09 / 196,364 filed on November 19, 1998, which was filed on June 6, 1997. This is a partial continuation of US Patent Application No. 08 / 870,664; and a partial continuation of US Patent Application No. 09 / 268,171 filed March 15, 1999. Fully incorporate into.

【0002】

(Technical Field of the Present Invention) The present invention relates to a structure and a composition for enhancing the stability of a peroxide active substance, and more particularly, a structure for use in a tooth whitening system containing a peroxide active substance. And the composition.

【0003】

(Background of invention) Whitening teeth has been very popular over the past few years. More and more consumers are choosing to whiten their teeth. Options for whitening teeth include toothpaste, mouthwash, chewing gum, office bleach, and most commonly whitening teeth used with trays either over-the-counter or obtained from a dentist. The solution can be mentioned. The tooth whitening solution contains an active ingredient that bleaches teeth. The solution is placed in a dental tray worn by the patient to bleach the teeth. Oral compositions usually come in squeeze bottles, tubes or syringes. It is known that active substances that whiten teeth can be difficult to keep stable over a long period of time. The most common dental bleach is peroxides, which are known to be extremely reactive. To improve stability, the peroxide may be encapsulated, blended into two parts of the composition, or a stabilizer may be added to maintain the level of the peroxide. Generally, the peroxide composition is stored in a sealed bulky container such as a syringe or tube.

【0004】

Teeth whitening systems containing non-bulky, tooth whitening composition strips and pre-divided tooth whitening compositions are available in US Pat. Nos. 5,984,017, 5,879,691, 5,891,453, 6,045,811. No. 5 and No. 5,989,569, which are incorporated herein by reference. Such an improved system provides a disposable, user-friendly means for whitening teeth. It is even more difficult to stabilize an oral composition containing peroxide over the long term, as the oral composition is stored as a thin layer rather than as a syringe or progenitor.

【0005】

(Outline of Invention) Peroxide products are provided. Peroxide products include packaging with headspace, a substrate placed within the packaging, and a thin layer of composition with a peroxide active substance and a polyhydric alcohol, the thin layer adjacent to the substrate. Be placed. Peroxide products also include at least one means of increasing the stability of the peroxide active substance of the composition. The thin layer of the composition has at least about 43% of the original concentration of the peroxide active substance 12 months after production when stored at about 25 ° C. in the absence of light.

【0006】

(Detailed Description of Preferred Embodiments) References to the preferred embodiments of the present invention have now been made in detail, examples of which are described in the accompanying drawings, wherein similar numbers are consistently identical to the figures. Elements with the same last two digits (eg, 20 and 120) or alphabetic suffixes (eg, 22A and 22B) mean the same element. As discussed in more detail below, the present invention directs means of enhancing the stability of peroxide active substances. As used herein, the term "stability" refers to a peroxide active substance (or other stability) that seeks to maintain its original concentration over a defined period of time (eg, 3 months, 6 months, 12 months, etc.). It is intended to refer to the propensity of a non-active substance), in which the defined period is measured starting from the time the tooth whitening composition is produced or formed as a thin layer. Even small to moderate increases in the stability of the peroxide active material can significantly affect the shelf life of the peroxide system. For example, from a peroxide system having a composition that retains 28% after 12 months of the original concentration of 6% of the peroxide active substance, having a composition that retains 39% after 12 months of the original concentration of 6% of the peroxide active substance. The transition to the peroxide system allows the peroxide system to remain in store for an additional 3 months until it reaches a minimum effective concentration of 3%.

【0007】

A particularly preferred embodiment of the invention is described in FIG. 1, which comprises a tooth whitening system 20 consisting of a substrate 22, a thin layer 24 of a tooth whitening composition containing a peroxide active material, and a support material 26. Orient. Substrate 22 is used to apply the tooth whitening composition to the teeth, substantially preventing saliva from coming into contact with the tooth whitening composition, as well as the wearer's lips, tongue, and other It serves as a protective barrier to prevent erosion of the tooth whitening composition from the tooth surface by soft tissues. The support material 26 also serves as a protective barrier, but the substrate 22 and the thin layer 24 are separated from the support material 26 prior to the application of the tooth whitening composition to the teeth, thereby being used. To expose the thin layer 24. Means for increasing the stability of the tooth whitening composition are the concentration of polyhydric alcohol, the ratio of the volume of the thin layer 24 to the exposed surface area of the thin layer 24, the volume of the thin layer 24 and the exposure of the thin layer 24. Ratio to surface area not present, material forming at least part of the surface of substrate 22 or supporting material 26 in contact with the composition, volume of thin layer 24 to volume of packaging headspace, and combinations thereof. And can be any equivalent of them. Although the present invention discusses the tooth whitening system 20 herein for simplicity, the present invention relates to tartar prevention compositions, remineralization compositions, disinfectant compositions, gingival inflammation compositions, healing compositions. It is understood that it can be applied to other oral compositions containing peroxide active substances such as, etc. It is also considered that the present invention is suitable for use in other systems containing peroxide active substances such as fabric bleaching systems, hair bleaching systems, topical disinfection systems and the like. Moreover, the invention can also be used with compositions containing other unstable or volatile active substances such as alcohols, ethanol, ethers, menthol and other flavoring agents, methyl salicylate and the like. It is pondered.

【0008】

The tooth whitening composition contains a peroxide active substance and is present therein as a thin layer 24 between the support material 26 and the substrate 22. As used herein, "thin layer" is intended to refer to the physical formation or location of a tooth-whitening composition. The thin layer 24 of the tooth whitening composition is generally present on or in contact with the substrate 22 and the supporting material 26. The thin layer 24 of the tooth whitening composition may be stored, coated or spread on the supporting material 26. The thin layer 24 of the tooth whitening composition is preferably between about 0.01 mm and about 3 mm, more preferably between about 0.02 mm and about 2 mm, most preferably between about 0.05 mm and about 1 mm, even more most. It preferably has a thickness between about 0.07 mm and about 0.5 mm. Such measurements are obtained by measuring from the surface 28 of the support material 26 through the thin layer 24 of the tooth whitening composition. The thin layer of the tooth whitening composition is preferably a homogeneous, uniform and continuous layer, but the thin layer 24 may also be heterogeneous, discontinuous and / or heterogeneous. For example, the thin layer 24 is a laminated or separated layer of constituents, an amorphous mixture of constituents, separate strips or dots of different constituents or other patterns, or such a structure. Can be a combination of.

【0009】

The tooth whitening compositions of the present invention can be provided in the form of viscous fluids, pastes, gels, solutions, or any other state or phase capable of forming a thin layer. Preferably, the tooth whitening composition is provided in the form of a gel and at a low shear rate (approximately 1 second).^-1) Has a viscosity between about 200 and about 1,000,000 cps. More preferably, the viscosity is between about 100,000 and about 800,000 cps, and most preferably between about 150,000 and about 700,000 cps. Even more preferably, the viscosities are between about 300,000 and about 700,000 cps. The amount of tooth whitening composition provided to the tooth whitening system 20 will vary depending on the intended use, the size of the substrate 22, the concentration of the peroxide active substance, and the desired benefit. Generally, less than about 1 gram of tooth whitening composition is required for tooth whitening applications. Preferably, about 0.05 grams to about 0.5 grams, more preferably about 0.1 grams to about 0.4 grams of tooth whitening composition is provided. The amount of tooth whitening composition per square cm of substrate 22 is approximately 0.2 grams / cm.²Smaller, preferably about 0.005 to about 0.1 g / cm², More preferably about 0.01 g / cm²~ About 0.05g / cm²Is.

【0010】

As is known in the art, tooth whitening compositions also have yield stresses. Yield stress is the amount of force in a substance before it begins to move. The yield stress must be high enough to allow the tooth whitening composition to form a thin layer and to handle the obstacles caused by manufacturing, handling and storage. The yield stress of the tooth whitening composition is between about 2 and about 3000 pascals, preferably between about 20 and about 2000 pascals, more preferably between about 200 and about 1500 pascals, and most preferably. Is between about 400 Pascals and about 1200 Pascals.

【0011】

Suitable peroxide active substances for use in the present invention include hydrogen peroxide, calcium peroxide, carbamide peroxide, and mixtures thereof. The most preferable is hydrogen peroxide. Other peroxide active substances include compositions that produce hydrogen peroxide when mixed with percarbonates, especially water such as sodium percarbonate. The peroxide active substance can be present at any concentration, but the peroxide active substance is preferably present at a concentration of about 0.01% to about 40% by weight of the tooth whitening composition in a tooth whitening application. The peroxide active material is from about 0.1% to about 20% by weight, preferably from about 0.5% to about 15% by weight, more preferably from about 1% to about 10% by weight, and most preferably from about 1% to about 10% by weight of the composition that whitens the teeth. Should provide a concentration of hydrogen peroxide corresponding to about 2% to about 10% by weight. It is understood that such concentrations are expressed for hydrogen peroxide and that other molecules that release peroxides, such as carbamide peroxide, calcium peroxide, etc., must undergo appropriate conversion.

【0012】

Additional components of the tooth whitening composition may include water, gelling agents, moisturizers, pH regulators, stabilizers, desensitizers, and reaction promoters or bleach activators. However, it is not limited to this. In addition to the substances mentioned above, a number of other substances can also be added to the content. Additional substances include, but are not limited to, flavoring agents and sweetening agents such as saccharin, xylitol, opacifying agents, colorants, and chelating agents such as ethylenediaminetetraacetic acid. Such additional ingredients can be used in place of the compounds disclosed above. Suitable gelling agents for use do not react with or activate the components of the oral care composition. A common gelling agent is a swellable polymer. The effective concentration of the gelling agent that allows the tooth whitening composition to form a thin layer varies with each type of gelling agent. The thin layer has a viscosity and yield stress that allows the tooth whitening composition to form a thin layer on the supporting material. The tooth whitening composition formed by such an agent may provide sufficient sticky adhesion of the film material to the target area of the mouth. For example, the level of gelling agent for forming a tooth whitening composition with carboxypolymethylene is between about 0.1% by weight and about 15% by weight of the tooth whitening composition, preferably about 1% by weight. Between about 10% by weight, more preferably between about 2% and about 8% by weight, and most preferably between about 3% by weight and about 6% by weight. The effective concentration of the poroxamar gelling agent is between about 10% and about 40% by weight, preferably between about 20% and about 35% by weight, and even more preferably about 25% by weight of the tooth whitening composition. Between about 30% by weight.

【0013】

Suitable gelling agents useful in the present invention include "Pemulen" manufactured by BF Goodrich Company, carboxypolymethylene, carboxymethyl cellulose, carboxypropyl cellulose, hydroxyethyl cellulose, poroxamer, laponite, carrageenan, bee gum, carboxyvinyl polymer. Examples thereof include natural rubbers such as carrageenan gum, xanthan gum, guar gum, arabic rubber, tragacant rubber, and mixtures thereof. A preferred gelling agent for use in the present invention is carboxypolymethylene obtained from BF Goodrich Company. Particularly preferred carbopols include carbopols 934, 940, 941, 956, 971, 974, 980, and mixtures thereof. Particularly preferred is Carbopol 956. Carboxypolymethylene is a slightly acidic vinyl polymer with an active carboxyl group.

【0014】

Other suitable gelling agents include both polymers with limited solubility in water and polymers lacking solubility in water. Suitable adhesives with limited solubility in water include hydroxyethyl or propyl cellulose. Adhesives that lack water solubility include ethyl cellulose or polyox resin. Another adhesive that may be suitable for use in this composition is polyvinylpyrrolidone with a molecular weight of about 50,000 to about 300,000. Yet another potentially suitable adhesive for use in this composition is a combination of Gantrez and the semi-synthetic water-soluble polymer carboxymethyl cellulose. A pH regulator may also be added to produce a composition that is safe for the tissues of the mouth. Such a pH regulator, or buffer, can be any substance suitable for adjusting the pH of the composition. Suitable substances include sodium bicarbonate, sodium phosphate, sodium hydroxide, ammonium hydroxide, potassium hydroxide, sodium citrate, triethanolamine, citric acid, hydrochloric acid, sodium citrate, and combinations thereof. .. A pH regulator at a concentration sufficient to allow the pH of the composition to be adjusted between about 3 and about 10, preferably between about 4 and about 8.5, more preferably between about 4.5 and about 8. Add. The pH regulator is generally present between about 0.01% by weight and about 15% by weight of the composition, and preferably between about 0.05% by weight and about 5% by weight.

【0015】

Suitable stabilizers include benzoic acid, salicylic acid, butylated hydroxytoluene, tin salts, phosphates, and others. Suitable bleach activators include trichloroisocyanuric acid and phosphates such as tetrasodium pyrophosphate. Desensitizers may also be added to the tooth whitening composition. Such agents may be preferred for consumers with sensitive teeth. Desensitizers include potassium nitrate, citric acid, citrates, strontium chloride, and combinations thereof. Potassium nitrate is the preferred desensitizer. Other agents that provide the benefit of reducing tooth sensitivity are also included in the invention. Generally, the concentration of the desensitizer is between about 0.01% and about 10% by weight, preferably between about 0.1% and about 8% by weight, and even more preferably about 1% by weight of the tooth whitening composition. Between% and about 7% by weight.

【0016】

The substrate 22 may be formed from polymers, natural and synthetic fabrics, non-woven fabrics, foils, papers, rubbers, and combinations thereof. The base material 22 (as well as the supporting material 26) may be a single layer of material or a laminate of more than one layer. Suitable polymers include, but are not limited to, ethyl vinyl acetate, ethyl vinyl alcohol, polyesters such as MYLAR® manufactured by DuPont, and combinations thereof.

【0017】

The supporting material can be formed from any substance that has a lower affinity for the tooth whitening composition than the tooth whitening composition shows for itself and the substrate 22. For example, the support material 26 can be formed from paper or a polyester such as Scotch PAK® manufactured by 3M Corp., Minneapolis, Minnesota, where the substrate 22 is from the support material 26. It is coated with a non-sticking substance to aid in the release of the tooth whitening composition from the support material 26 when pulled apart. Typical coatings include waxes, silicones, Teflon®, fluoropolymers such as fluorosilicone, or other non-stick type materials. Suitable coatings are described in US Pat. Nos. 3,810,874, 4,472,480, 4,567,073, 4,614,667, 4,830,910, and 5,306,758, which are incorporated herein by reference. One of the coatings to be applied may be mentioned. A further description of suitable substances that may be suitable as release agents can be found in Kirk-Othmer's Encyclopedia of Chemical Technology, 4th Edition, Vol. 21, pp. 207-218, in the book for reference. Incorporate into the specification.

【0018】

The tooth whitening system 20 is described herein as including both the substrate 22 and the supporting material 26, but is based on the tooth whitening system 20 (or any other peroxide system within the scope of the invention). It is considered that only the material 22 and the thin layer 24 may be included. For example, the inside of the packaging that stores the base material 22 and the thin layer 24 is coated in the same manner as described above for the support material 26 to facilitate the removal of the base material 22 and the thin layer from the packaging during use. You may. In addition, the tooth whitening system 20 can be provided in roll form rather than planar form as shown herein and can include multiple substrates and / or support materials. It is pondered. Alternatively, it has been pondered that the substrate 22 and / or the supporting material 26 may include other non-planar shapes such as preformed dental trays or flexible dental trays. To. The substrate and / or supporting material also applies to the teeth a permanently deformable strip material, wax, or tooth whitening composition suitable for use as a barrier to the tooth whitening composition. It can be formed from any other material suitable for the above.

【0019】

While the above-mentioned materials relating to the substrate 22 and the supporting material 26 are suitable for use in the present invention, the stability of the peroxide active material of the thin layer 24 of the tooth whitening composition is the supporting material 26 and / or the group. It is improved if the material 22 (or at least the surface 28 and / or 30 in contact with the peroxide active material) is formed from polyolefin, preferably polyethylene or polypropylene. While such substances are preferred, polyolefin mixtures, polyethylene mixtures, polypropylene mixtures, and combinations thereof are also considered suitable for use as the substrate 22 and / or the supporting material 26 in the present invention. As discussed above, the support material 26 can also be coated to aid in the release of the tooth whitening composition from the support material 26 during manufacturing and / or use. However, proper selection of the underlying material remains desirable, as such coatings generally do not act as a barrier between the peroxide active material and the underlying material. However, any coating should be inactive compared to the peroxide active material.

【0020】

It has been further found that the stability of peroxides is negatively affected by the presence of polyesters, especially polyhydric alcohols. Therefore, at least a portion of the surfaces 28 and 30 of the substrate 22 and / or the supporting material 26 that come into contact with the tooth whitening composition is preferably polyester so that the material containing the polyester does not come into contact with the tooth whitening composition. It is formed from substances other than. More preferably, the base material 22 and / or the supporting material 26 is completely formed of a substance other than polyester. Polyesters and peroxide active substances have been found to have negative interactions in the absence of polyhydric alcohols, but the combination of all three components has a further negative synergistic effect on the stability of the peroxide active substances. The base material 22 and / or the supporting material 26 is generally less than about 1 mm thick, preferably less than about 0.05 mm thick, more preferably about 0.001 to about 0.03 mm thick. Even more preferably, the base material 22 and / or the supporting material 26 has a thickness of less than 0.1 mm, and even more preferably a thickness of about 0.005 to about 0.02 mm. The thickness and permeability of the substrate 22 and / or the supporting material 26 can affect the stability of the tooth whitening composition. In general, thick strips may provide even greater stability for tooth whitening compositions. However, the thickness of the substrate must be balanced with consumer tolerance for the comfort of wearing the strip.

【0021】

In the tooth whitening system 20, the substrate 22 can be sized according to its application, but the substrate is sized so that it is individually matched to the desired tooth or dentition to be bleached. Generally this is the 6-8 teeth in the upper or lower dentition that the wearer sees when laughing, or in front of either the maxillary or mandibular dentition. Optionally, the substrate 22 may fit the entire upper or lower dentition when placed against the tooth. Most preferably, the substrate 22 is sized to overlap one of the gingival margins and sized to cover at least six central anterior teeth (from canines to canines). The substrate 22 can be a strip for the upper jaw that is approximately 6.5 cm long x 1.5 cm wide with a rounded rectangle, and / or the substrate 22 is a trapezoid with rounded corners 5.0 cm long x 2.0 cm wide. It can be a strip for the lower jaw that is cm. Further descriptions of the size and shape of substrate 22 in tooth whitening applications are disclosed in US Patent Application No. 09 / 268,185, filed March 15, 1999, with reference to this specification. Fully incorporate into the book. The support material 26 should be at least the same size and shape as the substrate 22 as shown in FIG. 1, but the support material 26 extends beyond the substrate 22 as shown by the example in FIG. This is more convenient for the support material 26, and the base material 22 and the thin layer 24 can be removed from the support material 26.

【0022】

The substrate 22 should have a relatively low flexural rigidity so that it can cover the uneven tooth surface with very little force to be exerted; that is, it is substantially flat. Maintains the curvature and fit of the wearer's mouth, teeth, and tooth gaps, as there is little residual force in the substrate that results from trying to return to a good shape. The flexibility of the substrate allows it to contact adjacent soft tissues for extended periods of time without physical irritation. The substrate does not require pressure to form it against the tooth and, when applied, easily fits into the gaps between the tooth surface and the tooth space without permanent deformation.

【0023】

Flexural rigidity is a physical property that is a combined function of strip thickness, width, and elastic modulus of a substance. This test is a method of measuring the rigidity of polyolefin films and sheets. It measures the resistance of the sample to bending using a strain gauge attached to the end of the horizontal beam, the opposite end of the beam is pressed across the strip of the sample and the water on which the sample is placed. Forcibly insert a part of the strip into the vertical groove on the flatbed. A micro ammeter wired to a strain gauge calibrates the refractive power in grams. Sample rigidity is read directly from a micro-ammeter and expressed as grams of sample strip width per centimeter. In embodiments that are preferred but not required in the present invention, the flexible substrate is a Handle-O-Meter (Handle) available from Swing-Albert Instrument, Philadelphia, PA. -O-Meter) model # 211-300 test method ASTM It has a flexural rigidity of less than about 5 grams / cm as measured by D2923-95. Preferably, the substrate 22 has a flexural rigidity of less than about 4 grams / cm, more preferably less than about 3 grams / cm, and most preferably about 0.1 grams / cm to about 1 grams / cm.

【0024】

For tooth whitening compositions, it is often desirable to include a moisturizer as a component of the composition. Moisturizers provide rheological stability and / or physical stability and provide users with a variety of aesthetics. However, for common moisturizers such as polyhydric alcohols (eg glycerin, sorbitol, polyethylene glycol, propylene glycol), the stability of the peroxide active material is due to the high concentration of moisturizer, especially in the presence of polyester. Is negatively affected. Thus, according to yet another aspect of the invention, the polyhydric alcohol in the thin layer 24 of the tooth whitening composition is less than about 40% by weight, preferably about 0% by weight and about 35% by weight of the tooth whitening composition. It is present in concentrations between%, more preferably between about 1% by weight and about 30% by weight, and most preferably between about 5% by weight and about 15% by weight. Further, such a low polyhydric alcohol concentration is more preferably used in combination with a supporting material 26 and / or a substrate 22 having surfaces 28 and 30 in contact with a tooth whitening composition formed from a substance other than polyester. Be done. More preferably, such a low polyhydric alcohol concentration is present in combination with the supporting material 26 and / or the substrate 22 having surfaces 28 and 30 in contact with the tooth whitening composition formed from the polyolefin.

【0025】

As the concentration of polyhydric alcohol decreases, the rest of the tooth whitening composition is between about 65% and about 99% by weight of the total tooth whitening composition, preferably about 70% by weight and about 95% by weight. Water can be contained between%, more preferably at concentrations between about 70% by weight and about 90% by weight. This concentration of water includes free water added in addition to the amount introduced with other substances. The increased water composition improves the stability of the peroxide when it is associated with the liquid phase of the composition and the physicochemistry of the composition (eg, vapor / fluid equilibrium). Chemically, it replaces glycerin as the concentration of water increases. As the concentration of water increases, the molar ratio of water to peroxide decreases. This reduces the vapor equilibrium concentration of peroxide in the vapor phase. In a fixed headspace system (eg, packaging 34 in Figure 3), there is less total peroxide in the vapor phase. Peroxides react in the vapor phase. Therefore, lowering the concentration of polyhydric alcohol reduces the reaction rate in the vapor phase. This also slows the degradation of peroxides in the gel phase as it is a reservoir that maintains headspace equilibrium. Thus, elevated levels of water in the formulation slow the decomposition of chemical reactions in the liquid phase and thus the decomposition of the vapor phase, thereby maintaining higher concentrations of peroxide over a given period of time.

【0026】

According to yet yet another aspect of the invention, it has been found that the stability of the thin layer 24 of the tooth whitening composition can be improved by proper selection of the exposed surface area and volume of the thin layer 24. As used herein, the term "exposed surface area" refers to the side surface area of the thin layer 24 of the tooth whitening composition that is directly exposed to the headspace 32 of the sealed packaging 34 (FIG. 34) (reference number 50). (Shown in the figure for illustration purposes) as, but volume is intended to mean the volume of the thin layer 24 of the tooth whitening composition. As used herein, the phrase "headspace" is intended to refer to the empty volume of packaging 34 (ie, without a tooth whitening system). For example, a thin layer 24 having a length of 5 mm, a width of 5 mm, and a thickness of 0.1 mm and having only a side surface area of 50 exposed to the headspace 32 is 0.2 mm.²Exposed surface area and 0.25mm³Has a volume of. The ratio of the exposed surface area of the thin layer 24 to the volume of the thin layer 24 is about 0.15 mm.^-1Less than, and more preferably about 0.05 mm^-1And about 0.15mm^-1Between. Most preferably, the ratio of the exposed surface area of the thin layer 24 to the volume of the thin layer 24 is about 0.05 mm.^-1And about 0.1mm^-1Between.

【0027】

Packaging 34 can be provided in various shapes and sizes. However, it is desirable that the shape and size of the packaging 34 closely match the shape and size of the tooth whitening system 20. Packaging can be provided in pouches, boxes, plastic containers, envelopes, bags, or other suitable forms known in the art. A supply of sufficient systems for whitening teeth is available as multiple packages 34 and a system 20 for whitening teeth can be bundled or otherwise provided as a set. Is. More preferably, the volume of headspace 32 of packaging 34 is about 0.1 mm.³And about 30,000mm³Between, more preferably about 50 mm³And about 10,000mm³Between. The ratio of the volume of headspace 32 to the volume of thin layer 24 is between 1 and about 500, preferably between 1 and about 400. More preferably, the ratio of the volume of headspace 32 to the volume of thin layer 24 is between 1 and about 200, and most preferably between 1 and about 100. Packaging 34 should be made from substances that are not translucent, have little or no moisture permeability, and are generally impermeable. Packaging 34 may be made from one or more substances and may optionally have a lining. For example, the pouch can be made from foil and have a polyethylene lining. Other suitable substances that are not translucent and impede the permeability of moisture include plastics, paper, foil, cardboard, polymers and rubber. Secondary packaging (not shown) for storing multiple packaging 34 can also be provided.

【0028】

With reference to FIGS. 4-6, preferred embodiments of the present invention are now described in which the ratio of the exposed surface area of the thin layer 24 to the volume of the thin layer 24 is as small as possible. The tooth whitening system 120 includes a substrate 122 having a first section 36 applied to the teeth and a second section 38 remaining with the supporting material 26. A fragile, otherwise divisible separation (eg, perforated lines, partial slits, etc.) is used in place of the slit 40, and the first of substrate 122 and until the user is completely separated. The second compartments 36 and 38 can be interconnected at least partially, but the first and second compartments 36 and 38 are preferably separated by a slit 40 through the thickness of the substrate 122. The slit 40 is preferably substantially U-shaped in plan view, with both ends 42 of the slit 40 extending from a common end 44 of the substrate 122. While this arrangement is preferred, it will be appreciated that other slit arrangements can be provided. As best seen in FIG. 6, the first and second sections 36 and 38 of the substrate 122 are layered on the first and second sections 46 and 48 of the thin layer 124 of the tooth whitening composition, respectively. ing. In other words, the first section 46 of the tooth whitening composition has substantially the same spread as the first section 36 of the base material 122, while the second section 48 of the tooth whitening composition is the base material. It has substantially the same spread as the second division 38 of 122. The first and second compartments 46 and 48 of the tooth whitening composition are preferably integrated with each other during use until separated to enhance the stabilizing effect of the second compartment 42. However, as will be described more fully below, partial or complete separation of the tooth whitening composition between the first and second compartments 46 and 48 may occur during the operation of forming the slit 40. That is understood. The increase in the exposed surface area 50 from the addition of the second section 48 of the thin layer 124 of the tooth whitening composition is relatively small, whereas the thin layer 124 of the composition whitening the teeth from the addition of the second section 48 Whitening teeth due to the relatively large increase in volume

【0029】

Another preferred embodiment of the present invention will be described in the form of a tooth whitening system 220 with reference to FIGS. 7 and 8. The tooth whitening system 220 includes a substrate 22, a thin layer 24 of the tooth whitening composition, and a supporting material 226 having a recess 52 therein. The thin layer 24 of the tooth whitening composition is substantially surrounded by a recess 52 and a portion of the substrate 22 to minimize the ratio of the volume of the thin layer 24 to the exposed surface area of the thin layer 24. In a practical sense, the exposed surface area of the thin layer 24 is zero as the tooth whitening composition is completely surrounded by the recess 52 and the substrate 22 so that it is not exposed to the headspace of the packaging. It is considered that the substrate 22 may simply be stretched to the edge of the recess 55, but the substrate 22 and the supporting material 126 are preferably outside the recess 52, as best seen in FIG. Directly adjacent to each other.

【0030】

Yet another preferred embodiment of the present invention will be described with reference to FIG. The tooth whitening system 320 includes a support material 26, two substrates 22A and 22B, and a thin layer (not shown) of the tooth whitening composition. The substrates 22A and 22B are preferably aligned adjacent to each other to minimize the size of the packaging that stores the tooth whitening system 320. The size and shape of the substrates 22A and 22B are selected to provide the above-mentioned values for the ratio of the volume of the tooth whitening composition to the exposed surface area. Depending on the shape and size of the base material, the base materials 22A and 22B can be separated at the gap. Similarly, the thin layers can be integrally formed or separated at a gap. As for the tooth whitening system 20, it is possible to provide similar or different shapes to the substrates 22A and 22B as described above. When more than one substrate is provided in a single packaging 34, the exposed surface area and volume of the tooth whitening composition of the tooth whitening system is a thin layer associated with each substrate in the packaging. It is the sum of the contributions from 24A and 24B.

【0031】

In addition to the embodiments described above, another composition containing a peroxide active substance is added to the headspace of the packaging, thereby thinning the composition to whiten the teeth by increasing the exposed surface area of the tooth whitening system. It is considered that the stability of the peroxide active material in layer 24 can be improved. With reference to FIG. 11 for illustrative purposes, the tooth whitening system 420 can include one or more groups 54 of compositions containing peroxide with an exposed surface in the headspace of the packaging. Group 54 may be provided as a film, hemispherical group, polyhedral group, or any other shape and size. The group 54 is described as being placed on top of the support material 26, while one or more groups may be placed on the inner wall 56 of the packaging (see, eg, FIG. 3), or 1 It is considered that one or more groups may be placed on the sheet or another supporting material in the headspace 32 of the packaging 34.

【0032】

Further according to a further aspect of the invention, it has been found that the stability of the peroxide active material can be improved by proper selection of the unexposed surface area of the thin layer 24 and the volume of the thin layer 24. As used herein, the term "unexposed surface area" is the surface area that is not directly exposed to the packaging headspace, such as surface area 31 (FIG. 2) placed adjacent to substrate 22 and supporting material 26. Intended to point to. The ratio of the unexposed surface area of the thin layer 24 to the volume of the thin layer 24 is about 105 cm.^-1Less than, more preferably about 40 cm^-1And about 100 cm^-1Between. Most preferably, the ratio of the unexposed surface area of the thin layer 24 to the volume of the thin layer 24 is about 60 cm.^-1And about 85 cm^-1Between. Generally, a polyhydric alcohol concentration of less than about 40%, the exposed surface area of the thin layer 24 and about 0.15 mm^-1Ratio to less than thin layer volume, unexposed surface area of the thin layer and about 105 cm^-1Tooth whitening systems with less than one ratio to the volume of the thin layer, or material forming the surface of the substrate 22 and / or the supporting material 26 in contact with the tooth whitening composition, are post-manufacturing. At 12 months it may have a peroxide active material between about 45% and about 70% of its original concentration. Optionally, such a tooth whitening system has a peroxide active substance between about 50% and about 60% of its original concentration 12 months after manufacture.

【0033】

It has been found that the greatest increase in the stability of the peroxide active material results from a decrease in the concentration of polyhydric alcohol or a decrease in the ratio of the exposed surface area of the thin layer 24 to the volume of the thin layer 24. A modest increase in the stability of the peroxide active material is achieved by the material of the supporting material and the substrate, as well as the reduction in the value of the ratio of the unexposed surface area of the thin layer to the volume of the thin layer 24. Polyhydric alcohol concentration less than about 40%, exposed surface area of thin layer 24 and about 0.15 mm^-1Ratio to less than thin layer volume, unexposed surface area of the thin layer and about 105 cm^-1Tooth whitening systems with less than one ratio to the volume of the thin layer, or material forming the surface of the substrate 22 and / or the supporting material 26 in contact with the tooth whitening composition, are post-manufacturing. At 12 months it may have a peroxide active material between about 45% and about 100% of its original concentration. Optionally, such a tooth whitening system has a peroxide active substance between about 50% and about 60% of its original concentration 12 months after manufacture. Optionally, such tooth whitening systems have about 45% to about 85% of the original concentration of peroxide active material 12 months after manufacture. Other embodiments of such a tooth whitening system may have a peroxide active substance between about 50% and about 75% of the original concentration, which is present 12 months after production, or 12 after production. It may have a peroxide active substance that is present in the month between about 50% and about 70% of its original concentration.

【0034】

With reference to FIG. 11, the preferred method of forming the tooth whitening system 120 is now described. As is well understood, this method can also be adapted to manufacture other preferred tooth whitening systems described herein. The sheet 60 of the support material 26 is spread from the roller 62 and sent to the drum 64. The sheet 60 of the support material 26 may be formed by several filmmaking processes known in the art. Sheet 60 of the support material 26 (as well as sheet 66 of the substrate 22) may be formed by several filmmaking processes known in the art. The sheet 60 and the sheet 66 can be manufactured by a blowing process or a casting process. Steps such as extrusion and other steps that do not affect the flexural rigidity of the substrate may also be used. Nozzle 68 sprays a thin layer 70 of tooth whitening composition onto sheet 60 of support material 26. Sheet 66 of the substrate 22 is unfolded from the roller 70 and lightly presses a thin layer 70 of the tooth whitening composition, thereby forming a laminate of three layers. The laminate is fed into the roller 72 to create a slit 40, and similarly cut through the sheet 66 of the substrate 22 and the thin layer 70 of the substance 22 to whiten the teeth, and the outer edges 74 of its second compartments 38 and 48 (FIG. 5 ) Is specified. After the cutting and slitting operations on the roller 72, the excess of the sheet 66 of the substrate 22 is picked up by the roller 76, thereby placing the first and second compartments of the substrate 22 and the teeth on the sheet 60 of the supporting material 26. Leave the composition to whiten. The roller 78 cuts the support material 26 to form a system 120 that whitens individual teeth. The excess support material 26 is picked up by the roller 80, while the tooth whitening system 120 is collected by the conveyor 82, after which the tooth whitening system is inserted into packaging 34 to form a packaged peroxide product. Can be done. It is understood that such steps can be reconfigured, deleted and other steps can be added as is known in the art.

【0035】

In general, post-manufacturing tooth whitening systems 20 are used in packaging 34 (and / or in secondary packaging or packaging) between about 20 ° C and about 45 ° C and in the absence of virtually light. So, at least part of this storage time (usually 2-4 months) is considered to be refrigerated, but it is stored for at least about 12 months. More preferably, the tooth whitening system is stored at approximately room temperature (eg, about 25 ° C) in the absence of light. After storage, the user can open the packaging 34 and a tooth whitening system is removed from the packaging 34. Following storage, at least part of the tooth (and more preferably the entire tooth) is whitened after applying the tooth whitening composition with substrate 22 to the tooth. As used in this patent, the term "whitening" is intended to refer to a delta or change in tooth color using the CIE LAB measurement method described in this patent.

【0036】

After storage, the tooth whitening composition is applied to the teeth for about 5 to 120 minutes, preferably about 30 to about 60 minutes per day. Generally, this is done at least once a day for about 7 days and about 28 days, and more preferably twice a day for about 7 days and 14 days. The amount of time and number of days within this prescribing plan includes several, including the desired amount of whitening or bleaching, the wearer's teeth, and whether it is desired to whiten or maintain for the first time or to be bleached. Depends on the factors of. Therefore, the total number of applications is from about 1 to about 42, and more preferably from about 5 to about 28. After 12 months of storage and application of the prescription plan described above, the tooth whitening system provides a delta b * value of about -1, about -1.25, about -1.5, or about -2 or less. , Minus sign is b in the negative direction (ie less yellow in the CIE LAB color space)^*It means the direction along the axis. More preferably, Delta b^*Is between about -1.25 and about -5, and most preferably delta b^*Is between about -2 and about -5. The delta L value is about -1, about -1.25, about -1.5, or about -2 or less, where the minus sign is on the L axis in the negative direction (ie, increasing the brightness in the CIE LAB color space). It means the direction along. More preferably, the delta L value is between about -1.25 and about -5, and most preferably the delta L value is between about -2 and about -5. The delta a * value is between about -3 and about +3, where the plus and minus signs mean directions along the a * axis in the positive and negative directions, respectively. Delta a because tooth color can change geographically because of diet^*Values can rise or fall considerably depending on the terrain. The value of delta e is (in the art, delta L squared, delta a^*The square root of the sum of the square of the value and the square of the delta b * value) is between about 1 and about 7.7.

【0037】

(Example) Examples of preferable tooth whitening compositions produced based on the present invention are shown in the following table. All ingredients in the next tooth whitening composition should be mixed until homogeneous.

【0038】

[table 1]<img file="JP2004501173A_D0001.tif" /> 【0039】

[Table 2]<img file="JP2004501173A_D0002.tif" /> 【0040】

Method for Measuring Peroxide Active Substance Ratio and Concentration The values of the peroxide active substance ratio and concentration disclosed in the present specification are measured by the following methods. Store packages containing the peroxide system for the specified period (eg, 12 months) and under conditions. After the specified storage period, the peroxide concentration is measured using the iodine titration method. Iodine titration is a known standard method in the art for measuring peroxide concentrations. Generally, the method is carried out by weighing the composition containing the substrate and the peroxide active material, dissolving the composition in 1 M sulfuric acid and reacting the peroxide with excess potassium iodide in the presence of ammonium molybdate. Titrate to a clear end point with a known concentration of sodium thiosulfate using a starch indicator. Upon completion of titration, the substrate is weighed and the difference determines the composition weight. The peroxide concentration in the composition is then calculated. For long storage periods, the concentration of the peroxide active material is, otherwise, after at least 120 days, the concentration is measured as described above, and then the rest using first-order rate theory as is known in the art. It can be determined by extrapolation during the period. As is known in the art, the methods described above are performed immediately after the production of the peroxide product and at the end of the designated storage period to determine the absolute peroxide concentration as well as the percentage at which the original concentration remains. ..

【0041】

How to Measure Whitening Whitening as used herein can be measured according to the 1976 CIE LAB color space, where the L value measures the brightness and is from 100 for perfect white to zero for black. It changes to the value. a^*Values evaluate to red when positive, gray when zero, and green when negative. b b^*Values are evaluated as yellow when positive, gray when zero, and blue when negative. In the present specification, La is using a spectroscopic analyzer known in the art.^*b b^*Values can be measured, using the same lighting conditions for the first measurement prior to whitening and the second measurement after whitening. A suitable spectroscopic analyzer to use is the Photo Research Spectrascan PR650 manufactured by Photo Research, Chatsworth, California. Light is provided by a white light source. The light source should provide vertically polarized light, such as the use of a polarizing filter. A suitable filter for use is the HN38 polarizing filter manufactured by 3M Corporation of Minneapolis, Minnesota. Other filters such as the infrared reflection filter of the filter that raises the color temperature of the light source can be used. A good light source is Dedo in Crystal Falls, Michigan. Manufactured by Electric) and fitted with 150 watt, 24 volt Xenophot HLX bulbs, respectively manufactured by Osram, Germany. Other polarized white light sources can be used, as is known in the art. The light source is placed 14 inches away from the spectroanalyzer located between the light source. The light source focuses on the chin rest 12 inches from the lens of the spectroanalyzer. The three-dimensional arrangement of the light source, spectroanalyzer and chin rest can be varied to match the focal characteristics of the various spectroanalyzers. The light focuses on the chin rest at an angle of approximately 45 degrees. L^*a^*b b^*Set the spectroanalyzer to the mode and calibrate against the white standard as is known in the art. To measure the color of the teeth, the subject places the jaw on the chin rest and pulls the cheeks back with a lip tower so that the light source illuminates the teeth.

【0042】

Each whitening measurement gives two whitening measurements that the spectroanalyzer evaluates the color characteristics of the subject's teeth by focusing on the center of the tooth. For the best tooth whitening system, the central maxillary incisor is the whitened tooth. If a tooth whitening system is used to whiten more than one central maxillary incisor, then each measurement applies a tooth whitening system for no more than four central maxillary incisors. L^*a^*b b^*It is necessary to measure the value. 4 L of such central maxillary incisors^*a^*b b^*A single set of L on average^*a^*b b^*Reach the value. A first measurement is required prior to the application of the tooth whitening system and a second measurement is required after the application and exclusion of the tooth whitening system (ie, after whitening occurs). Delta L^*a^*b b^*The value is the difference between the first and second measurements. Although specific embodiments of the present invention have been illustrated and described, it is clear to the person concerned that various changes and modifications can be made without departing from the spirit and purpose of the present invention, and the scope of the present invention. All amendments within are intended to be included in the accompanying claims.

[Simple explanation of drawings]

FIG. 1 is a perspective view of a preferred tooth whitening system produced according to the present invention.

FIG. 2 is a cross-sectional side view of the tooth whitening system of FIG. 1 along line 2-2.

FIG. 3 is a cross-sectional side view of the preferred tooth whitening system of FIG. 1 placed in a package.

FIG. 4 is a perspective view of another preferred tooth whitening system manufactured according to the present invention.

5 is a cross-sectional side view of the tooth whitening system of FIG. 4 along line 5-5.

FIG. 6 is a perspective view of the tooth whitening system of FIG. 4 with the first portion of the substrate removed.

FIG. 7 is a perspective view of yet another preferred tooth whitening system produced according to the present invention.

8 is a cross-sectional side view of the tooth whitening system of FIG. 7 along line 8-8.

FIG. 9 is a plan view of yet another preferred tooth whitening system manufactured according to the present invention.

FIG. 10 is a plan view of a more preferred tooth whitening system manufactured according to the present invention.

11 is a schematic diagram of a method of manufacturing the tooth whitening system of FIG. 1. FIG.