JP7657212B2 - Oral Composition - Google Patents

Description

The present invention relates to an oral composition.

Condensed phosphates are known to be effective in preventing stains from adhering to teeth, but they have the problem of being highly irritating to the oral mucosa, which is particularly noticeable in liquid preparations such as mouthwashes. Patent Document 1 discloses the use of specific flavoring ingredients to reduce the irritation caused by pyrophosphate and polyphosphates. Patent Document 2 proposes preparations that incorporate hydroxyalkyl cellulose to reduce the irritation through viscosity, as well as masking the irritation with flavoring ingredients.

JP 2011-98917 A Patent No. 6217628

However, the technology of Patent Document 1 does not provide sufficient effects for oral compositions, especially liquid preparations, and there are problems with the durability of the irritation relief, particularly with preparations that are not rinsed with water, such as mouthwashes and mouth sprays, as the irritation remains strong. Furthermore, the technology of Patent Document 2 has problems such as reduced palatability and inability to completely mask for long periods of time.

The present invention aims to provide an oral composition that can reduce the irritating sensation caused by irritating ingredients such as ingredients that inhibit stain adhesion to teeth, while still exerting the original effects of the irritating ingredients.

The present invention provides the following [1] to [11].
[1] An oral composition comprising component (A): one or more selected from condensed phosphoric acid, phytic acid, and salts thereof; and component (B): (N-(2-(2-pyridinyl)ethyl)-2-isopropyl-5-methylcyclohexanecarboxamide).
[2] The oral composition according to [1], wherein the component (A) is one or more selected from pyrophosphoric acid, tripolyphosphoric acid, hexametaphosphoric acid, ultraphosphoric acid, phytic acid, and salts thereof.
[3] The oral composition according to [1] or [2], wherein the amount of component (A) is 0.05 to 2 mass%.
[4] The oral composition according to any one of [1] to [3], wherein the amount of the (B) component is 0.00001 to 0.01 mass%.
[5] The oral composition according to any one of [1] to [4], further comprising one or more selected from the group consisting of organic acids having 3 to 6 carbon atoms and salts thereof as component (C).
[6] The oral composition according to [5], wherein the component (C) is one or more selected from malic acid, tartaric acid, citric acid, lactic acid, succinic acid, fumaric acid, and salts thereof.
[7] The oral composition according to [5] or [6], wherein the amount of component (C) is 0.05 to 3 mass%.
[8] An oral composition described in any one of [1] to [7], which is a liquid oral composition.
[9] An agent for reducing irritation of irritating components in an oral composition, comprising (N-(2-(2-pyridinyl)ethyl)-2-isopropyl-5-methylcyclohexanecarboxamide).
[10] The irritation-relieving agent according to [9], wherein the irritating component is one or more selected from the group consisting of condensed phosphoric acid, phytic acid, and salts thereof.
[11] An oral composition comprising a stimulating ingredient and (N-(2-(2-pyridinyl)ethyl)-2-isopropyl-5-methylcyclohexanecarboxamide).

According to the present invention, an oral composition is provided which can inhibit stain adhesion to teeth, inhibit the sensation of irritation and maintain the inhibiting effect, and can realize these effects through good flavor expression and improved appearance stability of the formulation.

The present invention will be described in detail below with reference to preferred embodiments thereof. In this specification, the content of each component is based on the amount of each component charged when preparing the composition.

[1. Oral composition]
The oral cavity composition of the present invention contains components (A) and (B) and may further contain component (C). Components (A) to (C) will be described below.

<Component (A)>
The component (A) is at least one selected from the group consisting of condensed phosphoric acid, phytic acid, and salts thereof. The component (A) enables the oral composition to exhibit a stain adhesion inhibitory effect.

Condensed phosphoric acid includes, for example, linear polyphosphoric acid such as pyrophosphoric acid, tripolyphosphoric acid, and tetrapolyphosphoric acid; cyclic polyphosphoric acid such as trimetaphosphoric acid, tetrametaphosphoric acid, and hexametaphosphoric acid; and mesh-like polyphosphoric acid such as ultraphosphoric acid. As linear polyphosphoric acid, pyrophosphoric acid and tripolyphosphoric acid are preferred, and as cyclic polyphosphoric acid, hexametaphosphoric acid is preferred. As condensed phosphoric acid, linear polyphosphoric acid is preferred. Condensed phosphoric acid and phytic acid may be in the form of a salt. Examples of the salt include inorganic base salts such as alkali metal salts (e.g., sodium salt, potassium salt), alkaline earth metal salts (e.g., calcium salt, magnesium salt), copper salt, zinc salt, aluminum salt, and ammonium salt; and organic base salts such as triethylammonium salt, triethanolammonium salt, pyridinium salt, and diisopropylammonium salt. Preferably, it is an alkali metal salt or an alkaline earth metal salt, more preferably a sodium salt, potassium salt, or calcium salt, and even more preferably a sodium salt or potassium salt. The component (A) preferably contains one or more selected from linear polyphosphoric acid and phytic acid, and more preferably contains one or more selected from pyrophosphoric acid, a sodium salt of tripolyphosphoric acid, and phytic acid.

The (A) component may be one selected from condensed phosphoric acid, phytic acid, and salts thereof, or a combination of two or more. As a combination of two or more, two or more selected from polyphosphoric acid and its salts are preferred, and it is preferable that the combination includes one or more linear polyphosphoric acid and its salts. Such combinations include a combination of one or more selected from linear polyphosphoric acid and its salts with one or more selected from cyclic polyphosphoric acid, mesh polyphosphoric acid, and their salts; and a combination of two or more selected from linear polyphosphoric acid and its salts. In addition, the (A) component, condensed phosphoric acid, phytic acid, and their salts, may be mixed with other phosphoric acids or phosphates in the oral composition.

The amount of component (A) is usually 0.05% by mass or more, and preferably 0.1% by mass or more, based on the total amount of the oral composition. This allows for a better stain adhesion inhibitory effect to be achieved. The upper limit is usually 2% by mass or less, and preferably 1% by mass or less. This allows for the oral composition to suppress the irritation felt by the oral mucosa, and suppresses a decrease in flavor expression and appearance stability. Therefore, the amount of component (A) is usually 0.05 to 2% by mass, and preferably 0.1 to 1% by mass.

<Component (B)>
The component (B) is (N-(2-(2-pyridinyl)ethyl)-2-isopropyl-5-methylcyclohexanecarboxamide). By including the component (B), the occurrence of irritation in the oral composition can be suppressed, and the suppression of the irritation can be further sustained.

The amount of component (B) is not particularly limited, but is usually 0.00001% by mass or more, and preferably 0.0001% by mass or more, based on the total amount of the oral composition. This makes it possible to suppress the irritating sensation of the oral composition and to obtain a sustained suppressing effect. The upper limit is usually 0.01% by mass or less, and preferably 0.005% by mass or less. This makes it possible to suppress the onset of a strong irritating sensation and to suppress a decrease in flavor expression. Therefore, the amount of component (B) is usually 0.00001 to 0.01% by mass, and preferably 0.0001 to 0.005% by mass.

The ratio (A/B) of the amount of component (A) to the amount of component (B) is usually 20 or more, preferably 50 or more, and more preferably 80 or more. The upper limit is usually 30,000 or less, preferably 20,000 or less, and more preferably 10,000 or less.

<Component (C)>
Component (C) is one or more selected from organic acids having 3 to 6 carbon atoms and salts thereof. By including component (C), the oral composition can exhibit a better stain adhesion inhibitory effect.

Examples of organic acids having 3 to 6 carbon atoms include monocarboxylic acids, dicarboxylic acids, tricarboxylic acids, and oxycarboxylic acids, with malic acid, tartaric acid, citric acid, lactic acid, succinic acid, and fumaric acid being preferred. Examples of salts include inorganic base salts such as alkali metal salts (e.g., sodium salt, potassium salt), alkaline earth metal salts (e.g., calcium salt, magnesium salt), and ammonium salts; and organic base salts such as triethylammonium salt, triethanolammonium salt, pyridinium salt, and diisopropylammonium salt, with alkali metal salts and alkaline earth metal salts being preferred, sodium salt, potassium salt, and calcium salt being more preferred, and sodium salt or potassium salt being even more preferred.

The amount of component (C) is usually 0.05% by mass or more, and preferably 0.1% by mass or more, based on the total amount of the oral composition. This can further improve the effect of inhibiting stain adhesion. The upper limit is usually 3.0% by mass or less, and preferably 1.5% by mass or less. If it exceeds 3.0% by mass, there is a possibility that the appearance stability and flavor expression will decrease. Therefore, the amount of component (C) is usually 0.05 to 3% by mass, and preferably 0.1 to 1.5% by mass.

<Dosage form>
The dosage form of the oral composition is not particularly limited, but may be, for example, solid, paste, or liquid, with liquid being preferred. In this specification, an oral composition in a liquid dosage form is referred to as a liquid oral composition. The liquid oral composition can be prepared as a liquid such as a mouthwash (e.g., gargle, mouthwash), liquid toothpaste, or mouth freshener, and may be a concentrated type as necessary. The oral composition may be any of a medicine, a quasi-drug, a cosmetic, or a food.

<Optional ingredients>
In addition to the above components, the oral composition of the present invention may contain optional components other than the above components as necessary. The optional components can be appropriately selected depending on the application and formulation of the oral composition. For example, when the oral composition is a liquid, the optional components include surfactants, humectants, pH adjusters, preservatives, sweeteners, flavorings, active ingredients, and solvents. When the oral composition is in a formulation other than a liquid, the optional components other than the above-mentioned optional components include, for example, binders and abrasives. The content of the optional components is not particularly limited, and can be set to the amount used in a normal oral composition as long as it does not impair the effect of the present invention.

(Surfactant)
Examples of the surfactant include anionic surfactants, nonionic surfactants, cationic surfactants, and amphoteric surfactants, and it is preferable to include at least one of anionic surfactants and nonionic surfactants. By including an anionic surfactant in the oral composition, the effect of inhibiting stain adhesion can be further improved. By including a nonionic surfactant in the oral composition, the effect of solubilizing oil-soluble components can be obtained.

Examples of anionic surfactants include alkyl sulfates, N-acyl amino acid salts, α-olefin sulfonates, N-acylsulfonates, N-acyltaurates, and sulfates of glycerin fatty acid esters, with alkyl sulfates and N-acyltaurates being preferred. Examples of alkyl sulfates include alkyl sulfates having 12 to 14 carbon atoms (e.g., alkali metal salts of lauryl sulfate, myristyl sulfate). Examples of N-acyl amino acid salts include acyl amino acid salts such as acyl glutamate and acyl sarcosine salts having a saturated or unsaturated hydrocarbon group (e.g., having 8 to 18 carbon atoms, preferably 12 to 16 carbon atoms; may be either linear or branched). Examples of acyltaurate salts include N-acyl methyl taurine salts having a saturated or unsaturated hydrocarbon group (e.g., having 8 to 18 carbon atoms, preferably 12 to 16 carbon atoms; may be either linear or branched). Examples of the α-olefin sulfonate include α-olefin sulfonates having 10 to 16 carbon atoms, such as tetradecene sulfonate, etc. As these salts, alkali metal salts such as sodium salts and potassium salts are preferred.

The amount of anionic surfactant is usually 0.01% by mass or more based on the total amount of the oral composition. This allows for a better stain adhesion inhibitory effect to be achieved. The upper limit is usually 3% by mass or less, preferably 0.5% by mass or less, and more preferably 0.3% by mass or less. This allows for the inhibition of the onset of a strong irritating sensation. Therefore, the amount of anionic surfactant is usually 0.01 to 3% by mass, preferably 0.01 to 0.5% by mass, and preferably 0.01 to 0.3% by mass.

Examples of nonionic surfactants include polyoxyethylene fatty acid esters such as polyoxyethylene hydrogenated castor oil, polyoxyethylene glycerin fatty acid esters, and polyoxyethylene sorbitan fatty acid esters; polyoxyethylene higher alcohol ethers such as polyoxyethylene alkyl ethers; sugar alcohol fatty acid esters; sorbitan fatty acid esters; polyglycerin fatty acid esters; and polyoxyethylene sorbitan fatty acid esters. The average number of moles of ethylene oxide added to polyoxyethylene hydrogenated castor oil is usually 20 to 150 moles, preferably 20 to 130 moles, and more preferably 40 to 110 moles.

The amount of nonionic surfactant is usually 0.1% by mass or more, preferably 0.3% by mass or more, based on the total amount of the oral composition. The upper limit is usually 1% by mass or less, preferably 0.8% by mass or less. By being within these ranges, a better solubilization effect of oil-soluble components can be obtained. Therefore, the amount of nonionic surfactant is preferably 0.1 to 1% by mass, preferably 0.3 to 0.8% by mass.

Examples of cationic surfactants include quaternary ammonium compounds such as alkyl ammonium compounds and alkyl benzyl ammonium compounds. Examples of amphoteric surfactants include alkyl amido betaine type amphoteric surfactants; acetate betaine type amphoteric surfactants such as alkyl dimethyl amino acetate betaine and fatty acid amido propyl dimethyl amino acetate betaine; and imidazoline type amphoteric surfactants such as N-fatty acid acyl-N-carboxymethyl-N-hydroxyethyl ethylenediamine salts.

(Wetting Agent)
The oral composition contains a humectant, which can improve the feeling of use. Examples of the humectant include sugar alcohols such as sorbitol, erythritol, maltitol, lactitol, and xylitol; and polyhydric alcohols such as glycerin, propylene glycol, ethylene glycol, and polyethylene glycol. The polyhydric alcohols are preferably glycerin and propylene glycol, and the sugar alcohols are preferably sorbitol and xylitol.

The amount of humectant is usually 3% by mass or more, preferably 5% by mass or more, based on the total amount of the oral composition. The upper limit is usually 40% by mass or less, preferably 30% by mass or less, more preferably 15% by mass or less. By keeping it within these ranges, a better effect of improving the feel when used can be obtained. Therefore, the amount of humectant is usually 3 to 40% by mass, preferably 3 to 30% by mass, more preferably 5 to 15% by mass.

(pH adjuster)
The pH stability of the formulation can be ensured by including a pH adjuster in the oral composition. The components (A) and (C) of the present invention act as pH adjusters in the composition, but other optional pH adjusters can be further used as necessary. Examples of the optional pH adjusters include phthalic acid, orthophosphoric acid, acetic acid, carbonic acid, ribonucleic acid, and salts thereof (preferred examples are the same as in the component (A), preferably potassium salts, sodium salts, and ammonium salts), sodium hydroxide, and hydrochloric acid, and are preferably orthophosphoric acid or a salt thereof, and more preferably sodium dihydrogen phosphate, sodium monohydrogen phosphate, potassium dihydrogen phosphate, and potassium monohydrogen phosphate. When an optional pH adjuster is used, the amount of the optional pH adjuster can be an amount capable of adjusting the pH at 25°C to 5.5 to 8.5, preferably 6 to 8. For pH adjustment, citric acid or a salt thereof is preferably used, and further an orthophosphate is preferably used in combination. The pH can be measured immediately after preparation of the oral composition at 25°C and after 3 minutes using a pH meter (model number HM-25R) manufactured by DKK-TOA Corporation. By adjusting the pH of the oral composition of the present invention to fall within the above range, demineralization of tooth enamel can be inhibited, and efficacy and stability can be maintained.

(Preservatives)
The oral composition contains a preservative, which can ensure the preservative power of the preparation. Examples of the preservative include paraoxybenzoic acid esters such as methyl paraoxybenzoate and ethyl paraoxybenzoate, sodium benzoate, alkyldiaminoethylglycine hydrochloride, and potassium sorbate.

(Sweetening Agent)
The oral composition contains a sweetener, which can improve the feeling of use. Examples of the sweetener include sugar alcohols such as xylitol, maltitol, erythritol, and sorbitol; and high-intensity sweeteners such as saccharin, aspartame, sucralose, acesulfame potassium, stevia, neohesperidin hydrochalcone, glycyrrhizin, perillartine, p-methoxycinnamic aldehyde, and thaumatin.

(Fragrance)
The inclusion of a fragrance in the oral composition can improve the feeling of use and suppress the initial irritation after use. For example, a fragrance containing menthol and carvone can be used, but any fragrance used in oral compositions can be used without any particular limitation. The content of menthol and carvone in a fragrance containing menthol and carvone is preferably 10 to 80% by mass. Essential oils containing these, such as peppermint oil, Japanese peppermint oil, and spearmint oil, can also be used. The amount of the fragrance is usually 0.00001% by mass or more relative to the total amount of the oral composition, and the upper limit is usually 3% by mass or less, but is not particularly limited.

(Active ingredient)
Examples of the active ingredient include anti-inflammatory agents such as tranexamic acid and epsilon-aminocaproic acid; enzymes such as dextranase, amylase, protease, mutanase, lysozyme and Liteque enzyme; fluorine-containing compounds such as sodium fluoride, sodium monofluorophosphate and stannous fluoride; allantoin or derivatives thereof such as aluminum chlorohydroxyallantoin and allantoin; vitamin C such as ascorbic acid; plant extracts such as thyme, Scutellaria baicalensis, clove and witch hazel; dentin hypersensitivity inhibitors such as strontium chloride, potassium nitrate and aluminum lactate; azulene, lysozyme chloride, dihydrocholesterol, glycyrrhetin salts, glycyrrhetinic acids, hydrocholesterol, chlorophyll, copper chlorophyllin sodium, copper gluconate, caropeptide, water-soluble inorganic phosphate compounds, polyethylene glycol, polyvinylpyrrolidone, sodium lauroyl sarcosine, anti-tartar agents and anti-plaque agents, but are not particularly limited as long as they are active ingredients used in oral compositions. The content of the above-mentioned active ingredient can be appropriately determined to be an effective amount according to a conventional method.

(solvent)
When the oral composition is in a liquid formulation, it usually contains a solvent. Examples of the solvent include water (e.g., purified water) and alcohol (e.g., lower monohydric alcohol such as ethanol). Usually, it is water, and alcohol can be added as necessary. However, any solvent that can be used in the oral composition in a liquid formulation can be used, and is not particularly limited. When ethanol is added as a solvent, the amount is usually 30% by mass or less, preferably 20% by mass or less, based on the total amount of the oral composition, but it is not necessary to add it. By being in this range, it is possible to improve the feeling of suppressing bad breath during use.

(Binding Agent)
Examples of the binder include any suitable organic binder known in the art, such as polysaccharides, cellulose-based binders (e.g., carboxymethylcellulose (CMC), hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, methylcellulose, cationic cellulose, etc.), other polysaccharide-based thickeners (e.g., xanthan gum, guar gum, gellan gum, tragacanth gum, karaya gum, arabic gum, locust bean gum, carrageenan, sodium alginate), and synthetic water-soluble polymers (e.g., sodium polyacrylate, carboxyvinyl polymer, polyvinylpyrrolidone, polyvinyl alcohol, propylene glycol alginate). Furthermore, inorganic binders such as thickening silica and aluminum silicate can also be contained. When a binder is added, the content is usually 0.01 to 10% by mass based on the total amount of the oral composition.

(Abrasive)
The abrasive may be either inorganic or organic. Examples of inorganic abrasives include abrasive silica such as precipitated silica, aluminosilicate, zirconosilicate, crystalline zirconium silicate, and titanium-bonded silica; calcium phosphate compounds such as calcium diphosphate dihydrate or anhydrous, calcium monophosphate, calcium triphosphate, and calcium pyrophosphate; calcium carbonate abrasives such as calcium carbonate; calcium abrasives other than carbonate/phosphate such as calcium hydroxide and calcium sulfate; aluminum materials such as aluminum oxide, aluminum hydroxide, and alumina; silicic acid materials such as anhydrous silicic acid, zeolite, and zirconium silicate; magnesium materials such as magnesium carbonate and magnesium triphosphate; apatite materials such as hydroxyapatite, fluoroapatite, and calcium-deficient apatite; titanium materials such as titanium dioxide, titanium mica, and titanium oxide; and minerals such as bentonite. Examples of organic abrasives include polymethyl methacrylate and synthetic resin abrasives. Among these, silica abrasives are preferred. When an abrasive is included, its content is usually 70% by mass or less, preferably 50% by mass or less, and more preferably 8 to 50% by mass, based on the total amount of the oral composition.

The method of using the oral composition of the present invention is not particularly specified. In the case of a liquid oral composition, for example, a method of putting an appropriate amount in the mouth and rinsing the mouth for several tens of seconds can be mentioned. In addition, the teeth can be brushed after rinsing the mouth.

<Applications>
The oral composition is useful as a stain adhesion improver because stain adhesion can be suppressed by applying the oral composition to teeth. The target subjects are not particularly limited. For example, subjects who wish to improve stain adhesion caused by food and beverages such as black tea, green tea, and coffee, and subjects who have not developed these symptoms but wish to prevent them, etc. can be mentioned.

<Method of producing oral composition>
The oral composition of the present invention can be produced by mixing the above-mentioned components. The order in which the components are mixed is not particularly limited, but it is preferable to mix the components uniformly.

2. Irritation Relief Agents
The above component (B), (N-(2-(2-pyridinyl)ethyl)-2-isopropyl-5-methylcyclohexanecarboxamide), is useful as an irritation reducer for the irritating component contained in the oral composition. Examples of the irritating component include one or more selected from the above component (A), condensed phosphoric acid, phytic acid, and salts thereof, as well as irritating components having a structure similar to these, but are not particularly limited as long as they are components that can be contained in the oral composition and cause irritation during use. The amount of the irritation reducer used may be an amount that suppresses irritation caused by the irritating component in the oral composition, and may be an amount exemplified as the amount of the above component (B). The oral composition may be an oral composition that contains a irritating component, and when the irritating component is component (A), an oral composition containing the amount exemplified as the amount of the above component (A) is preferred. The formulation of the oral composition and optional components that may be contained as necessary are not particularly limited.

[3. Oral cavity composition containing stimulating components]
The above component (B), (N-(2-(2-pyridinyl)ethyl)-2-isopropyl-5-methylcyclohexanecarboxamide), is useful as an irritation-relieving agent, and can therefore be an essential component of the oral composition together with the irritating component as an irritation-relieving component. The amount of the irritating component may be any amount as exemplified in the explanation of the irritation-relieving agent.

The present invention will be described in detail below with reference to examples. The following examples are provided to better explain the present invention, and are not intended to limit the present invention. Note that "%" means "% by mass" unless otherwise specified. The amounts of each component shown in the following tables are values converted to pure content (AI). The amount of water (balance) includes the amount of water carried over by each component.

The main raw materials used are listed below:
・Sodium pyrophosphate (manufactured by Taihei Chemical Industry Co., Ltd.)
Evercool (registered trademark) 190 (N-(2-(2-pyridinyl)ethyl)-2-isopropyl-5-methylcyclohexanecarboxamide, manufactured by Givaudan Japan)
Evercool (registered trademark) 180 ((1R,2S,5R)-N-(4-(cyanomethyl)phenyl)-2-isopropyl-5-methylcyclohexane-carboxamide, manufactured by Givaudan Japan)
WS-3 (N-ethyl-p-menthane-3-carboxamide, manufactured by Symrise Japan Co., Ltd.)
・Sodium lauroyl sarcosine (Kawaken Fine Chemicals Co., Ltd.)
・Glycerin (manufactured by Sakamoto Pharmaceutical Co., Ltd.)
- Sorbitol solution (Mitsubishi Corporation Life Sciences Co., Ltd.)
- Ethanol (manufactured by Japan Alcohol Industry Co., Ltd.)
・Sodium saccharin (Aisan Chemical Industry Co., Ltd.)
Polyoxyethylene hydrogenated castor oil 100E.O. (manufactured by Nippon Emulsion Co., Ltd.)
Polyoxyethylene hydrogenated castor oil 60 E.O. (manufactured by Nippon Emulsion Co., Ltd.)
Sodium lauryl sulfate (PT BASF Indonesia)
- Citric acid (manufactured by Komatsuya Co., Ltd.)
・Sodium citrate (manufactured by Komatsuya Co., Ltd.)

Fragrance The fragrance having the composition shown in Table 1 was used.

・Purified water (Kosakai Pharmaceutical Co., Ltd.)
Other ingredients used were those that conformed to the Standards for Quasi-Drug Ingredients 2006.

[Examples 1 to 20 and Comparative Examples 1 to 4]
<How to prepare mouthwash>
Mouthwashes were prepared by uniformly mixing each component according to the composition shown in Tables 2 to 5 (the content of each component in the tables is in mass %). Specifically, POE hydrogenated castor oil was added to ethanol and stirred, after which an oil layer with the fragrance dissolved therein was prepared, and the oil layer was added to an aqueous layer with the other components dissolved in purified water, and the mixture was uniformly dissolved using a Three-One Motor (BL1200, manufactured by HEIDON) to prepare the mouthwash. The pH (25°C) of the prepared mouthwash was 6.5 to 8.0.

<Evaluation method>
(1. Stain adhesion suppression effect)
The surface of an untreated hydroxyapatite pellet (HAP) (manufactured by HOYA Corporation, diameter 7 mm x thickness 3.5 mm) was treated with abrasive paper and washed with an ultrasonic cleaner, and then the initial color difference was measured with a colorimeter (UV-1800, manufactured by Shimadzu Corporation). Next, the HAP was immersed in saliva supernatant at 37°C for 30 minutes, and then (1) to (4) were repeated 10 times under the following conditions: (1) 1% mucin artificial saliva solution (50°C for 10 minutes), (2) 1% albumin artificial saliva solution (50°C for 10 minutes), (3) sample (room temperature for 30 seconds), and (4) stain solution (1% black tea powder aqueous solution) (50°C for 10 minutes). The color difference of the HAP after coloring, which was then washed with water and dried, was measured. The stain adhesion inhibition rate was calculated from Δb of the ^L* a ^* b ^* color system using the following formula. As a control in the formula, purified water was used instead of the sample, and the same series of operations as above were carried out. The color difference of this HAP was measured and Δb was calculated in the same manner.

A series of experimental procedures were performed with N=3 for each example and comparative example, and the stain adhesion inhibition rate of each HAP was calculated using the formula below, the average value was calculated, and the stain adhesion inhibition effect was evaluated using the evaluation criteria below.

(formula)
Stain adhesion inhibition rate (%)={1-(color difference change amount Δb of sample/color difference change amount Δb of control)}×100

· Criteria for determining the stain adhesion suppression effect +++: Stain adhesion suppression rate is 90% or more and 100% or less ++: Stain adhesion suppression rate is 70% or more and less than 90% +: Stain adhesion suppression rate is 50% or more and less than 70% ±: Stain adhesion suppression rate is 30% or more and less than 50% -: Stain adhesion suppression rate is less than 30%

(2. No irritation)
Participants were asked to place 20 mL of the mouthwash in their mouths and rinse for 20 seconds. The intensity of the irritation felt afterwards was then rated on the following four-point scale. The average score of the 10 participants was expressed as ++, +, ±, or - according to the following criteria.

・Evaluation criteria for lack of irritation 4 points: No irritation felt 3 points: Almost no irritation felt 2 points: Irritation felt 1 point: Very strong irritation felt ・Criteria for lack of irritation ++: Average score of 3.5 to 4.0 points +: Average score of 3.0 to less than 3.5 points ±: Average score of 2.0 to less than 3.0 points -: Average score of less than 2.0 points

(3. Duration of non-irritation sensation)
After placing 20 mL of the mouthwash in the mouth and rinsing for 20 seconds, the time during which no "irritation" was felt was evaluated on a four-point scale as shown below, and the average score of the 10 participants was expressed as ++, +, ±, or - according to the following criteria.

Evaluation criteria for duration of non-irritation: 4 points: 25 minutes or more (no irritation felt)
3 points: 15 to 25 minutes 2 points: 5 to 15 minutes 1 point: Less than 5 minutes

- Criteria for judging the duration of non-irritation: ++: average score of 3.5 to 4.0 points +: average score of 3.0 to less than 3.5 points ±: average score of 2.0 to less than 3.0 points -: average score of less than 2.0 points

(4. Good flavor expression)
20 mL of mouthwash was placed in the mouth and rinsing for 20 seconds, after which the flavor development during mouthrinsing was rated on the following four-point scale, and the average score of the 10 panelists was indicated as ++, +, ±, or - according to the following criteria.
Evaluation criteria for flavor expression: 4 points: Very good flavor expression; 3 points: Good flavor expression; 2 points: Not very good flavor expression; 1 point: Poor flavor expression

Judgment criteria for flavor expression: ++: Average score is 3.5 to 4.0 points +: Average score is 3.0 to less than 3.5 points ±: Average score is 2.0 to less than 3.0 points -: Average score is 1.0 to less than 2.0 points

(5. Evaluation of Appearance Stability of Formulations)
The prepared formulation was filled into a container with a capacity of 80 mL and allowed to stand at −5° C. for one month, and the appearance and properties were evaluated by visual inspection.

- Criteria for determining the appearance stability of the drug product ++: No precipitate or cloudiness is observed +: Almost no precipitate or cloudiness is observed ±: Precipitate or cloudiness is observed -: Significant precipitate or cloudiness is observed

Comparative Examples 1 to 4, which did not contain either component A or B, had problems such as no stain adhesion inhibitory effect, irritation, or a lack of irritation that was somewhat absent but did not last, whereas Examples 1 to 20, which contained components A and B, gave good results in the evaluations of stain adhesion inhibitory effect, lack of irritation, and duration of lack of irritation, and also gave good results in terms of flavor expression and appearance stability of the formulation. This shows that the oral composition of the present invention can inhibit stain adhesion to teeth, suppress irritation, and sustain the inhibitory effect.

As an example of a formulation, an example of a toothpaste formulation is shown in Table 6.

Claims (7)

Component (A): one or more selected from condensed phosphoric acid, phytic acid, and salts thereof ;
(B) component: (N-(2-(2-pyridinyl)ethyl)-2-isopropyl-5-methylcyclohexanecarboxamide) , and
Component (C): one or more selected from organic acids having 3 to 6 carbon atoms and their salts
It contains
The component (C) is at least one selected from malic acid, tartaric acid, citric acid, lactic acid, succinic acid, fumaric acid, and salts thereof,
An oral composition, wherein the ratio (A/C) of the amount of component (A) to the amount of component (C) is 0.25 to 20 . The oral composition according to claim 1, wherein component (A) is one or more selected from pyrophosphoric acid, tripolyphosphoric acid, hexametaphosphoric acid, ultraphosphoric acid, phytic acid, and salts thereof. The oral composition according to claim 1 or 2, in which the amount of component (A) is 0.05 to 2% by mass. The oral composition according to any one of claims 1 to 3, wherein the amount of component (B) is 0.00001 to 0.01% by mass. The oral composition according to claim 1 , wherein the amount of component (C) is 0.05 to 3 mass %. The oral composition according to any one of claims 1 to 5 , which is a liquid oral composition. 2. The oral composition according to claim 1, wherein the ratio (A/C) of the amount of component (A) to the amount of component (C) is 0.25 to 1.