Liquid oral composition

Abstract

To provide a liquid oral composition that contains glycyrrhizic acid and its derivatives and potassium nitrate, exhibits a desensitizing effect, effectively masks the salty or off-taste of potassium nitrate, and ensures favorable stability of glycyrrhizic acid salts.SOLUTION: There is provided a liquid oral composition comprising: (A) glycyrrhizic acid, or salts of glycyrrhizic acid such as sodium salt, potassium salt, or ammonium salt; (B) an inorganic water-soluble potassium salt such as potassium nitrate or potassium fluoride; and (C) a pyrrolidone carboxylic acid salt such as sodium pyrrolidone carboxylate, calcium pyrrolidone carboxylate, magnesium pyrrolidone carboxylate, zinc pyrrolidone carboxylate, or potassium pyrrolidone carboxylate.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a liquid oral composition.

Background Art

[0002] As a preventive measure for dentin hypersensitivity, it is known to incorporate potassium nitrate, which has a nerve desensitizing effect and is known as an active ingredient for preventing hypersensitivity, into an oral composition (for example, Patent Document 1). Potassium nitrate has a unique salty / bitter taste, and particularly in the case of mouthwash applications, it is desirable to mitigate this salty / bitter taste.

[0003] In addition, various active ingredients are incorporated into oral compositions for the purpose of preventing and treating oral problems. In particular, for the prevention and treatment of periodontal diseases, various active ingredients having an anti-inflammatory effect, a blood circulation promoting effect, a tissue activating effect, etc. are used. Among them, glycyrrhizic acids such as glycyrrhizic acid and its salts are widely used because they are active ingredients derived from natural products and have a high anti-inflammatory effect. Furthermore, glycyrrhizic acid and its salts have a sweetness intensity 100 to 200 times that of sucrose and are also used as high-sweetness sweeteners.

[0004] On the other hand, it has also been reported that an oral composition containing pyrrolidonecarboxylic acid can exhibit effects such as an anti-inflammatory effect and formulation stability (for example, Patent Document 2). Patent Document 3 describes that a liquid oral composition containing a pyrrolidonecarboxylic acid, a metal ion source such as potassium nitrate having a valence of 1 to 3, a compound having a LogPow value of 1 or more such as vitamin E, a water-soluble polymer compound, and an N-acylsarcosine salt has good appearance stability after storage at high temperature.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0006] In a liquid oral composition such as a mouthwash, when glycyrrhizic acids and potassium nitrate are combined to mask the unique salty / bitter taste of potassium nitrate, there is room for improvement in the stability (dispersion in the preparation) of glycyrrhizinate.

[0007] The present invention has been made in view of the above, and an object thereof is to provide a liquid oral composition containing glycyrrhizic acids and potassium nitrate, exhibiting a desensitizing effect, masking the salty / bitter taste of potassium nitrate, and having good stability of glycyrrhizinate.

MEANS FOR SOLVING THE PROBLEMS

[0008] The present invention provides the following [1] to

[10] . [1] A liquid oral composition containing (A) glycyrrhizic acid or a salt thereof, (B) an inorganic water-soluble potassium salt, and (C) a pyrrolidone carboxylate [2] The liquid oral composition according to [1], wherein the component (A) is at least one selected from the group consisting of sodium salt, potassium salt, and ammonium salt of glycyrrhizic acid. [3] The liquid oral composition according to [1] or [2], wherein the component (B) is at least one selected from potassium nitrate and potassium fluoride. [4] The liquid oral composition according to any one of [1] to [3], wherein the component (C) is at least one pyrrolidone carboxylate selected from sodium pyrrolidone carboxylate, calcium pyrrolidone carboxylate, magnesium pyrrolidone carboxylate, zinc pyrrolidone carboxylate, and potassium pyrrolidone carboxylate. ​The liquid oral composition according to any one of [1] to [4], wherein the content of component (A) is 0.001 to 2% by mass. The liquid oral composition according to any one of [1] to [5], wherein the content of component (B) is 0.1 to 10% by mass. The liquid oral composition according to any one of [1] to [6], wherein the content of component (C) is 0.1 to 20% by mass in terms of the amount of pyrrolidonecarboxylic acid. The liquid oral composition according to any one of [1] to [7], wherein the ratio (B) / (A) of the content of component (B) to the content of component (A) is 0.1 to 5000. The liquid oral composition according to any one of [1] to [8], wherein the ratio (C) / (B) of the content of component (C) to the content of component (B) is 0.01 to 200. The liquid oral composition according to any one of [1] to [9], wherein the ratio (C) / (A) of the content of component (C) to the content of component (A) is 0.1 to 10000.

Advantages of the Invention

[0009] According to the present invention, it is possible to provide a liquid oral composition that can exhibit a perception hypersensitivity inhibitory effect, has a good feeling in use due to masking of saltiness / undesirable taste, and has excellent stability due to good dispersibility of glycyrrhizic acid compounds.

Embodiments for Carrying Out the Invention

[0010] 〔1. Liquid Oral Composition〕 The liquid oral composition contains components (A) to (C).

[0011] [Component (A)] Component (A) is glycyrrhizic acid or a salt thereof. By containing glycyrrhizic acid or a salt thereof, an anti-inflammatory effect can be exhibited.

[0012] Examples of salts of glycyrrhizic acid include alkali metals such as sodium salt and potassium salt, and ammonium salt. Sodium salt, potassium salt, and ammonium salt are preferred, and potassium salt is more preferred. More specifically, for example, disodium glycyrrhizinate, trisodium glycyrrhizinate, dipotassium glycyrrhizinate, and monoammonium glycyrrhizinate can be mentioned, and dipotassium glycyrrhizinate is preferred. Glycyrrhizic acid or its salt may be derived from natural raw materials such as plants, or may be industrially manufactured. The component (A) may be one selected from glycyrrhizic acid and its salts, or may be a combination of two or more kinds.

[0013] The content of the component (A) in the liquid oral composition is preferably 0.002% by mass or more, more preferably 0.005% by mass or more. Thereby, the anti-inflammatory effect can be sufficiently exerted. The upper limit is preferably 1% by mass or less, more preferably 0.75% by mass or less. Thereby, rapid dispersion of the component (A) in the liquid preparation can be realized. Therefore, the content of the component (A) is preferably 0.002 to 1% by mass, more preferably 0.005 to 0.75% by mass.

[0014] [Component (B)] The component (B) is an inorganic water-soluble potassium salt. By containing an inorganic water-soluble potassium salt, the effect of suppressing hypersensitivity can be exerted.

[0015] Examples of the inorganic water-soluble potassium salt include potassium nitrate and potassium fluoride, and potassium nitrate is preferred. The inorganic water-soluble potassium salt may be derived from natural raw materials such as plants, or may be industrially manufactured. The component (B) may be one kind of inorganic water-soluble potassium salt, or may be a combination of two or more kinds of inorganic water-soluble potassium salts.

[0016] The content of component (B) in the liquid oral composition is preferably 0.1% by mass or more, more preferably 1% by mass or more. Thereby, the effect of suppressing hypersensitivity can be sufficiently exerted. The upper limit is preferably 10% by mass or less, more preferably 6% by mass or less. Thereby, the generation of the peculiar salty taste / undesirable taste derived from component (B) can be suppressed, and masking by other components can be achieved. Therefore, the content of component (B) is preferably 0.1 to 10% by mass, more preferably 1 to 6% by mass.

[0017] [Component (C)] Component (C) is a pyrrolidone carboxylate. By containing pyrrolidone carboxylate, the action of preventing root caries can be exerted, and the improvement of salty taste / undesirable taste and the improvement of stability can be achieved.

[0018] Pyrrolidone carboxylate is usually an inorganic salt, and examples thereof include alkali metal salts such as sodium pyrrolidone carboxylate and potassium pyrrolidone carboxylate, alkaline earth metal salts such as calcium pyrrolidone carboxylate and magnesium pyrrolidone carboxylate, and zinc pyrrolidone carboxylate. Among these, sodium pyrrolidone carboxylate is preferred. Pyrrolidone carboxylate may be derived from natural raw materials such as plants, or may be industrially manufactured. Component (C) may be one type of pyrrolidone carboxylate, or a combination of two or more types of pyrrolidone carboxylates.

[0019] The content of component (C) in the liquid oral composition (the amount of pyrrolidone carboxylic acid (excluding the salt), the same hereinafter) is preferably 0.1% by mass or more, more preferably 2% by mass or more. Thereby, the compounding effect of component (C) can be sufficiently exerted. The upper limit is usually 25% by mass or less, preferably 20% by mass or less, more preferably 18% by mass or less. Thereby, the above effects can be exerted, and by being less than the more preferable amount, the generation of the unique flavor derived from component (C) can be suppressed. Therefore, the content of component (C) is preferably 0.1 to 20% by mass, more preferably 2 to 18% by mass.

[0020] [(B) / (A)] The ratio (B) / (A) of the content of component (B) to the content of component (A) is preferably 0.1 or more, more preferably 0.12 or more. The upper limit is preferably 5000 or less, more preferably 4800 or less. Therefore, (B) / (A) is preferably from 0.1 to 5000, more preferably from 0.12 to 4800.

[0021] [(C) / (B)] The ratio (C) / (B) of the content of component (C) to the content of component (B) is preferably 0.01 or more, more preferably 0.012 or more. The upper limit is preferably 200 or less. Therefore, (C) / (B) is preferably from 0.01 to 200, more preferably from 0.012 to 200.

[0022] [(C) / (A)] The ratio (C) / (A) of the content of component (C) to the content of component (A) is preferably 0.1 or more, more preferably 0.12 or more. The upper limit is preferably 10000 or less, more preferably 9500 or less. Therefore, (C) / (A) is preferably from 0.1 to 10000, more preferably from 0.12 to 9500.

[0023] [Optional component] Depending on the dosage form and purpose of use described below, the liquid oral composition may contain, as necessary, appropriate known components in addition to the above components (A) to (C). Examples include surfactants, thickeners, preservatives, sweeteners, wetting agents, colorants, fragrances, pH adjusters, active ingredients, and solvents. When the liquid oral composition is a mouthwash, insoluble solid components such as abrasives are usually not contained.

[0024] Examples of the surfactant include nonionic surfactants, amphoteric surfactants, and anionic surfactants.

[0025] Examples of nonionic surfactants include polyoxyethylene alkyl ethers (e.g., polyoxyethylene cetyl ether), polyoxyethylene hydrogenated castor oil, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters (e.g., polyoxyethylene sorbitan monostearate), alkylolamides, polyoxyethylene fatty acid esters, polyoxyethylene alkenyl ethers, glycerin fatty acid esters, sucrose fatty acid esters (e.g., maltose fatty acid ester), sugar alcohol fatty acid esters (e.g., maltitol fatty acid ester, lactitol fatty acid ester), fatty acid diethanolamides (e.g., lauric acid mono- or diethanolamide), polyoxyethylene polyoxypropylene copolymers, and polyoxyethylene polyoxypropylene fatty acid esters. The number of carbon atoms in the alkyl chain of polyoxyethylene alkyl ethers is usually 14 to 18, and the average number of moles of ethylene oxide added is usually 15 to 30 moles. The average number of moles of ethylene oxide added to polyoxyethylene hydrogenated castor oil is usually 20 to 100 moles, preferably 60 to 100 moles. The number of carbon atoms in the fatty acid of sorbitan fatty acid esters is usually 12 to 18. The number of carbon atoms in the fatty acid of polyoxyethylene sorbitan fatty acid esters is usually 16 to 18, and the average number of moles of ethylene oxide added is usually 10 to 40 moles. The number of carbon atoms in the alkyl chain of alkylolamides is usually 12 to 14. As the nonionic surfactant, polyoxyethylene hydrogenated castor oil is preferred.

[0026] Examples of amphoteric surfactants include betaine types such as alkyldimethylaminoacetic acid betaine and fatty acid amidopropyldimethylaminoacetic acid betaine.

[0027] Examples of the anionic surfactant include alkyl sulfates, acyl amino acid salts, acyl taurine salts, α-olefin sulfonates, hydrogenated coconut fatty acid monoglyceride monosulfates, and alkyl sulfacetates. When having an alkyl group, the alkyl group may be either linear or branched, either saturated or unsaturated, and the number of carbon atoms thereof is usually 12 to 14. When having an acyl group, the acyl group may be either linear or branched, either saturated or unsaturated, and the number of carbon atoms thereof is usually 10 to 20. The salt may be selected from pharmacologically acceptable salts. Examples of the pharmacologically acceptable salts include inorganic base salts such as sodium salts, potassium salts, calcium salts, magnesium salts, and ammonium salts; organic base salts such as triethylammonium salts, triethanolammonium salts, pyridinium salts, and diisopropylammonium salts; and basic amino acid salts such as arginine salts, lysine salts, and histidine salts. Among them, inorganic base salts are preferred, alkali metal salts (for example, sodium salts, potassium salts) or ammonium salts are more preferred, and sodium salts are even more preferred.

[0028] Examples of the alkyl sulfate include lauryl sulfate and myristoyl sulfate. Examples of the acyl amino acid salt include acyl sarcosine salts such as lauroyl sarcosine salt and myristoyl sarcosine salt; acyl glutamate salts such as lauroyl glutamate salt, myristoyl glutamate salt, and palmitoyl glutamate salt; acyl glycine salts such as N-lauroyl-N-methylglycine salt and cocoyl glycine salt; acyl alanine salts such as N-lauroyl-β-alanine salt, N-myristyl-β-alanine salt, N-cocoyl-β-alanine salt, N-lauroyl-N-methyl-β-alanine salt, N-myristoyl-N-methyl-β-alanine salt, and N-methyl-N-acylalanine salt; and acyl aspartate salts such as lauroyl aspartate salt. Examples of the acyl taurine salt include lauroyl methyl taurine salt, N-methyl-N-acyl taurine salt, and N-cocoyl methyl taurine salt. Examples of the α-olefin sulfonate include α-olefin sulfonates having 12 to 14 carbon atoms such as tetradecene sulfonate. Other examples of the anionic surfactant include sodium hydrogenated coconut fatty acid monoglyceride monosulfate and sodium lauryl sulfacetate.

[0029] When the liquid oral composition contains the above surfactant, the total content of the surfactant is preferably 0.05 to 2.0%, more preferably 0.1 to 1.5%.

[0030] Examples of the thickener include cellulose-based compounds such as sodium carboxymethyl cellulose and gums such as xanthan gum. When the liquid oral composition contains a thickener, the content thereof is usually 0 to 3%.

[0031] Examples of the preservative include paraoxybenzoic acid ester, benzoic acid or its sodium salt.

[0032] Examples of the sweetener include sodium saccharin and sucralose.

[0033] Examples of the wetting agent include polyhydric alcohols. Examples of the polyhydric alcohols include sugar alcohols such as sorbitol, erythritol, maltitol, lactitol, xylitol; glycerin; glycols such as ethylene glycol, polyethylene glycol (molecular weight: 200 to 6000), propylene glycol; and reduced starch saccharides.

[0034] As the coloring agent, water-soluble dyes are preferred because of their high safety. For example, Food Blue No. 1, Green No. 3, Yellow No. 4, Red No. 105 can be mentioned.

[0035] Examples of the fragrance include various fragrance components and essential oils. Specifically, for example, menthol, carvone, anethole, cineole, methyl salicylate, cinnamic aldehyde, eugenol, 3-1-menthoxypropane-1,2-diol, thymol, linalool, linalyl acetate, limonene, menthone, menthyl acetate, N-substituted-p-menthane-3-carboxamide, pinene, octyl aldehyde, citral, pregeone, carvyl acetate, anisaldehyde, ethyl acetate, ethyl butyrate, allyl cyclohexanepropionate, methyl anthranilate, ethyl methyl phenyl glycidate, vanillin, undecalactone, hexanal, isoamyl alcohol, hexenol, dimethyl sulfide, cyclotene, furfural, trimethylpyrazine, ethyl lactate, methyl lactate, ethyl thioacetate and other fragrance components, peppermint oil, spearmint oil, anise oil, eucalyptus oil, wintergreen oil, cassia oil, clove oil, thyme oil, sage oil, lemon oil, orange oil, mint oil, cardamom oil, coriander oil, mandarin oil, lime oil, lavender oil, rosemary oil, laurel oil, chamomile oil, caraway oil, marjoram oil, bay oil, lemongrass oil, oregano oil, pine needle oil, neroli oil, rose oil, jasmine oil, iris concrete, absolute peppermint, absolute rose, orange flower and other natural fragrances, and fragrances obtained by processing these natural fragrances (such as cut of the fore fraction, cut of the back fraction, fractional distillation, liquid-liquid extraction, etc.), strawberry flavor, apple flavor, banana flavor, pineapple flavor, grape flavor, mango flavor, butter flavor, milk flavor, fruit mix flavor, tropical fruit flavor and other compound flavors. When the liquid oral composition contains a fragrance, its content is usually 0.00001 to 3%.

[0036] The pH of the liquid oral composition is preferably 5 or higher, more preferably 5.5 or higher at 5°C. This can sufficiently suppress the gelation of the liquid oral composition. The upper limit is preferably 7.7 or lower, more preferably 8 or lower at 25°C. This results in better appearance stability. Therefore, the pH of the liquid oral composition is preferably 5 to 8, more preferably 5.5 to 7.5 at 25°C. For pH adjustment, a combination of sodium dihydrogen phosphate and disodium hydrogen phosphate, or citric acid and sodium citrate may be contained as a pH adjuster.

[0037] Examples of the active ingredient include bactericidal or antibacterial agents such as cetylpyridinium chloride, benzalkonium chloride, benzethonium chloride, zinc gluconate, zinc citrate, triclosan, thymol, hinokitiol, lysozyme chloride, isopropylmethylphenol; enzymes such as dextranase, mutanase, amylase, protease, litic enzyme; fluorides other than potassium fluoride such as sodium fluoride, sodium monofluorophosphate, stannous fluoride; anti-inflammatory agents such as ε-aminocaproic acid, allantoin, tranexamic acid, glycyrrhetinate, aluminum chlorhydroxyallantoin, azulene, dihydrocholesterol; metal salts such as zinc, copper salts, tin salts; calculus preventives such as condensed phosphates, ethanehydroxydiphosphonate; sensitivity suppressants other than potassium nitrate such as aluminum lactate, strontium chloride; coating agents such as hydroxyethylcellulose dimethyldiallylammonium chloride; astringents such as sodium chloride, allantoin chlorhydroxyaluminum, vitamins (e.g., vitamin C, vitamin E), lysozyme chloride, glycyrrhetinic acid and its salts; water-soluble copper compounds such as copper chlorophyll, copper gluconate; calculus preventives such as zeolite, amino acids such as alanine, glycine, proline; plant extracts; caropeptide, polyvinylpyrrolidone, calculus inhibitor, dental plaque inhibitor. The content of the active ingredient can be appropriately set to an effective amount.

[0038] Examples of the solvent include purified water and lower monohydric alcohols such as ethanol. When the liquid oral composition contains a lower monohydric alcohol (e.g., ethanol), its content is preferably 10% or less, preferably 5% or less, more preferably substantially non-containing (e.g., below the detection limit), and even more preferably non-containing.

[0039] [2. Use] The liquid oral composition can be prepared and applied as a concentrated type or stock solution type mouthwash, liquid dentifrice, oral coolant, etc., and among them, a mouthwash is preferred.

Examples

[0040] Hereinafter, the present invention will be described by way of examples. The following examples do not limit the present invention.

[0041] Examples 1 to 31 and Comparative Examples 1 to 3 Liquid oral compositions (mouthwashes) having the compositions described in the following table were prepared according to a conventional method, and the following evaluations were performed.

[0042] [Evaluation method] <Evaluation of the effect of reducing tooth hypersensitivity> Three subjects with tooth hypersensitivity who felt transient pain when rinsing with water after brushing were used. The liquid oral composition was used in the usual method of using a mouthwash, and the degree of pain after spitting out was scored based on the following scoring criteria (1 to 4 points), and the effect of reducing tooth hypersensitivity was evaluated from the average value of the scores of the three subjects. The degree of pain before the start of the test was 1 point according to the following scoring criteria for all subjects.

[0043] (Scoring criteria for the degree of pain) 4 points: No pain is felt. 3 points: Almost no pain is felt. 2 points: Slightly painful. 1 point: Considerably painful.

[0044] (Evaluation criteria for the pain relief effect) ◎: 3.5 points or more and 4.0 points or less ○: 3.0 points or more and less than 3.5 points △: 2.0 or more and less than 3.0 points ×: less than 2.0 points

[0045] <Verification of the inhibitory effect of off - flavor / saltiness> It was evaluated by a sensory test using 10 expert panelists. The liquid oral composition was used in the normal mouthwash usage method, and the absence of off - flavor / saltiness felt after spitting out was evaluated according to the following scoring. The average value of the evaluation results of 10 people was calculated, and those that ensured the evaluations of ◎ and ○ according to the following criteria were judged to be compositions without off - flavor / saltiness (off - flavor / saltiness masked).

[0046] (Scoring criteria) 4 points: No off - flavor / saltiness at all 3 points: Almost no off - flavor / saltiness 2 points: Slightly off - flavor / saltiness 1 point: There is off - flavor / saltiness

[0047] (Evaluation criteria) ◎: 3.5 points or more and 4.0 points or less ○: 3.0 points or more and less than 3.5 points △: 2.0 points or more and less than 3.0 points ×: Less than 2.0 points

[0048] (Evaluation method of dispersibility) 3 L of the liquid oral composition was put into a stainless - steel container, 0.6 g of dipotassium glycyrrhizinate was added, and it was stirred at 200 rpm with a blade - type electric stirrer. The time until complete dispersion was measured, and the following dispersibility evaluation was carried out. ◎ and ○ were regarded as passing.

[0049] (Evaluation criteria) 4 points: Uniformly dispersed in less than 1 minute 3 points: Uniformly dispersed in 1 minute or more and less than 3 minutes 2 points: Uniformly dispersed in 3 minutes or more and less than 5 minutes 1 point: Not uniformly dispersed even after 5 minutes

[0050] (Judgment criteria) ◎: 3.5 points or more and 4.0 points or less ○: 3.0 points or more and less than 3.5 points △: More than 2.0 points and less than 3.0 points ×: Less than 2.0 points

[0051]

Table 1

[0052]

Table 2

[0053]

Table 3

[0054]

Table 4

[0055]

Table 5

[0056] Compared with the compositions of the comparative examples that did not contain any of the components (A) to (C), which were poorly evaluated in at least one of the effects of suppressing hypersensitivity, reducing off-flavor / saltiness, and dispersibility, the compositions of the examples containing the three components all had well-balanced and good evaluations.

[0057] These results indicate that the liquid oral composition of the present invention can exhibit an effect of suppressing hypersensitivity, has a good feeling in use due to masking of saltiness / off-flavor, and is also excellent in stability because of the good dispersibility of glycyrrhizic acids.

Claims

1. (A) glycyrrhizic acid or a salt thereof, (B) an inorganic water-soluble potassium salt, and (C) a pyrrolidone carboxylate A liquid oral composition containing the same.

2. The liquid oral composition according to claim 1, wherein the component (A) is at least one selected from the group consisting of sodium salt, potassium salt, and ammonium salt of glycyrrhizic acid.

3. The liquid oral composition according to claim 1 or 2, wherein the component (B) is at least one selected from potassium nitrate and potassium fluoride.

4. The liquid oral composition according to claim 1 or 2, wherein the component (C) is at least one selected from pyrrolidone carboxylates selected from sodium pyrrolidone carboxylate, calcium pyrrolidone carboxylate, magnesium pyrrolidone carboxylate, zinc pyrrolidone carboxylate, and potassium pyrrolidone carboxylate.

5. The liquid oral composition according to claim 1 or 2, wherein the content of the component (A) is 0.001 to 2% by mass.

6. The liquid oral composition according to claim 1 or 2, wherein the content of the component (B) is 0.1 to 10% by mass.

7. The liquid oral composition according to claim 1 or 2, wherein the content of the component (C) is 0.1 to 20% by mass in terms of the amount of pyrrolidone carboxylic acid.

8. The liquid oral composition according to claim 1 or 2, wherein the ratio (B) / (A) of the content of the component (B) to the content of the component (A) is 0.1 to 5000.

9. The liquid oral composition according to claim 1 or 2, wherein the ratio (C) / (B) of the content of the component (C) to the content of the component (B) is 0.01 to 200.

10. The liquid oral composition according to claim 1 or 2, wherein the ratio (C) / (A) of the content of component (C) to the content of component (A) is from 0.1 to 10,000.

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