Liquid oral components

Abstract

To provide a liquid oral composition containing activated carbon and having low-temperature stability, with the adsorption ability of the activated carbon to be effectively expressed.SOLUTION: A liquid oral composition contains activated carbon with an average particle size of 10 μm or less, and glycerol and / or propylene glycol, with the content of the activated carbon being 0.1 wt.% or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a liquid oral composition that contains activated carbon in an amount of 0.1% by weight or less, has low-temperature stability, and is capable of effectively exhibiting the adsorption capacity of the activated carbon. [Background technology]

[0002] Activated carbon is known to function as an adsorbent, and has been used in the field of oral compositions for purposes such as preventing or removing plaque and tartar, whitening teeth, and preventing or removing bad breath.

[0003] Various formulations of oral compositions containing activated carbon have been reported. For example, Patent Document 1 reports that a toothpaste containing a charcoal powder with a particle size of 10 to 500 μm is not dangerous to the human body even when used over time, has excellent toothpaste effects such as removing food debris, and provides a pleasant brushing sensation. Furthermore, Patent Document 2 reports that a toothpaste containing (A) granules and / or charcoal granules containing charcoal powder and (B) charcoal powder has an excellent appearance, with the contours of the granules and / or charcoal granules difficult to see. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-143467 [Patent Document 2] Japanese Patent Application Publication No. 2019-112376 Summary of the Invention [Problem to be solved by the invention]

[0005] Liquid oral compositions are often stored at low temperatures in winter or in cold regions, so they are desirable for low-temperature stability to prevent freezing. Furthermore, when other additives are adsorbed onto activated carbon in liquid oral compositions, blocking the pores of the activated carbon reduces its adsorption capacity. Therefore, when formulating a liquid oral composition containing activated carbon to achieve low-temperature stability, care must be taken to avoid adversely affecting the adsorption capacity of the activated carbon. In particular, when a liquid oral composition contains only a small amount of activated carbon (0.1 wt. % or less), it is necessary to fully express the adsorption capacity of the activated carbon. Therefore, when imparting low-temperature stability, it is extremely important to design a formulation that does not adversely affect the adsorption capacity of the activated carbon. However, the prior art has not reported a formulation technique for effectively expressing the adsorption capacity of activated carbon while also providing low-temperature stability in a liquid oral composition containing activated carbon.

[0006] Therefore, the object of the present invention is to provide a liquid oral composition which contains activated carbon at a content of 0.1% by weight or less, has low temperature stability, and can effectively express the adsorption ability of activated carbon. [Means for solving the problem]

[0007] The present inventors have conducted extensive research to solve the above problems and have found that by selecting activated carbon with an average particle size of 10 μm or less and incorporating the activated carbon in a liquid oral composition in combination with glycerin and / or propylene glycol at a content of 0.1% by weight or less, the liquid oral composition can be stabilized at low temperatures and the adsorption capacity of the activated carbon can be effectively expressed. Based on this finding, the present invention was completed through further research.

[0008] That is, the present invention provides the following aspects. Item 1. Contains activated carbon with an average particle size of 10 μm or less, and glycerin and / or propylene glycol, and A liquid oral composition having an activated carbon content of 0.1% by weight or less. Item 2. A liquid oral composition described in Item 1, containing 0.1 to 30 weight% of glycerin and / or propylene glycol. Item 3. A liquid oral composition according to Item 1 or 2, which is a mouthwash. [Effects of the Invention]

[0009] According to the present invention, a liquid oral composition containing activated carbon at a content of 0.1% by weight or less is provided with low-temperature stability that can prevent freezing even when stored at approximately -5°C, and the adsorption capacity of the activated carbon can be effectively expressed. DETAILED DESCRIPTION OF THE INVENTION

[0010] 1.Liquid oral composition The liquid oral composition of the present invention is characterized by containing activated carbon having an average particle size of 10 μm or less, and glycerin and / or propylene glycol, and the activated carbon content is 0.1 wt% or less. In the liquid oral composition of the present invention, activated carbon having an average particle size of 10 μm or less is selected and coexisted with glycerin and / or propylene glycol at a content of 0.1 wt% or less, thereby providing low-temperature stability and enabling the activated carbon to effectively exhibit its adsorption ability. The liquid oral composition of the present invention is described in detail below.

[0011] [Activated carbon] The liquid oral composition of the present invention contains activated carbon having an average particle size of 10 μm or less. The average particle size of the activated carbon used in the present invention may be 10 μm or less, but from the viewpoint of more effectively exhibiting the adsorption ability of the activated carbon, it is preferably 8 μm or less, more preferably 7 μm or less, and even more preferably 6 μm or less. The lower limit of the average particle size of the activated carbon used in the present invention is not particularly limited, but examples include 1 μm or more, preferably 2 μm or more, and more preferably 4 μm or more. More specifically, the average particle size of the activated carbon used in the present invention is 1 to 10 μm, preferably 2 to 8 μm, more preferably 3 to 7 μm, and even more preferably 4 to 6 μm. In the present invention, the average particle size of the activated carbon is defined as the particle size (median diameter, D) at which the cumulative degree reaches 50% in the volume cumulative standard particle size distribution measured by a wet method using a laser diffraction / scattering particle size distribution analyzer. 50 )

[0012] D of the activated carbon used in the present invention 10 The average particle diameter of the activated carbon is not particularly limited as long as it satisfies the above range, but may be, for example, 0.5 to 3 μm, preferably 1 to 1.5 μm. 10 is the particle size at which the cumulative percentage is 10% in the volume cumulative particle size distribution measured by a wet method using a laser diffraction / scattering particle size distribution analyzer.

[0013] In addition, the D of the activated carbon used in the present invention 90 The average particle diameter of the activated carbon is not particularly limited as long as it satisfies the above range, but may be, for example, 10 to 30 μm, preferably 15 to 20 μm. 90 is the particle size at which the cumulative percentage is 90% in the volume cumulative particle size distribution measured by the wet method using a laser diffraction / scattering particle size distribution analyzer.

[0014] The content of activated carbon in the liquid oral composition of the present invention may be 0.1% by weight or less, specifically 0.0001 to 0.1% by weight, more preferably 0.001 to 0.1% by weight, and even more preferably 0.005 to 0.05% by weight.

[0015] [Glycerin and / or propylene glycol] The liquid oral composition of the present invention contains glycerin and / or propylene glycol together with the activated carbon. In the liquid oral composition of the present invention, either glycerin or propylene glycol may be used alone, or they may be used together. Among these, glycerin is preferred from the viewpoint of more effectively expressing the adsorption ability of the activated carbon.

[0016] The content of glycerin and / or propylene glycol in the liquid oral composition of the present invention is, for example, a total amount of 0.1 to 30 weight %, preferably 1 to 25 weight %, and more preferably 5 to 20 weight %.

[0017] In addition, in the liquid oral composition of the present invention, the ratio of the activated carbon to glycerin and / or propylene glycol is determined according to the content ranges described above, but for example, per 1 weight part of the activated carbon, the total amount of glycerin and / or propylene glycol is 1 to 10,000 weight parts, preferably 100 to 5,000 weight parts, and more preferably 500 to 2,000 weight parts.

[0018] [water] The liquid oral composition of the present invention contains water as a solvent. The content of water in the liquid oral composition of the present invention may be the remainder excluding the added components.

[0019] [Other ingredients] The oral composition of the present invention may contain, if necessary, other medicinal ingredients in addition to the above-mentioned ingredients. Such medicinal ingredients are not particularly limited as long as they can be incorporated into oral compositions, and examples thereof include bactericides, bronchodilators, antitussives, expectorants, anti-inflammatory agents, glucosyltransferase inhibitors, plaque inhibitors, hypersensitivity inhibitors, anti-tartar agents, antipyretics, analgesics, antihistamines, bactericides, gastric mucosa protectants, caffeines, vitamins, herbal medicines, and herbal ingredients.

[0020] The liquid oral composition of the present invention may contain bases and additives to prepare the desired formulation. Such bases and additives are not particularly limited as long as they can be incorporated into the oral composition, and examples thereof include lower alcohols, polyhydric alcohols other than those mentioned above, sugar alcohols, oily components, surfactants, freshening agents, preservatives, thickeners, fragrances, flavoring agents, coloring materials, deodorizing components, pigments other than activated carbon, buffers, pH adjusters, etc.

[0021] [Form of formulation] The formulation form of the liquid oral composition of the present invention is not limited as long as it can be applied to the oral cavity and remain there for a certain period of time, and examples thereof include oral care products such as mouthwash, liquid dentifrice, oral spray (including throat spray), gargle, mouth freshener, etc. Among these, mouthwash and liquid dentifrice are preferred, and mouthwash is more preferred.

[0022] 2. Method for improving low temperature stability The method for improving low-temperature stability of the present invention is a method for improving low-temperature stability in a liquid oral composition containing activated carbon at a content of 0.1% by weight or less, and is characterized in that the liquid oral composition contains 0.1% by weight or less of activated carbon having an average particle diameter of 10 μm or less and a sugar alcohol.

[0023] In the method for improving low temperature stability of the present invention, the types and amounts of components used, the formulation form of the liquid oral composition, etc. are as shown in the section ``1. Liquid oral composition'' above.

[0024] 3. Methods for improving adsorption capacity The method for improving adsorption capacity of the present invention is a method for improving the adsorption capacity of activated carbon in a liquid oral composition containing activated carbon at a content of 0.1% by weight or less, and is characterized in that the liquid oral composition contains 0.1% by weight or less of activated carbon having an average particle diameter of 10 μm or less and a sugar alcohol.

[0025] The method for improving adsorption capacity of the present invention is a method carried out to prevent the decrease in the adsorption capacity of activated carbon in a liquid oral composition, and the types and amounts of ingredients used, the formulation form of the liquid oral composition, etc. are as shown in the section ``1. Liquid oral composition'' above. [Example]

[0026] The present invention will be explained in more detail below by showing examples, but the present invention is not limited to these examples.

[0027] Test Example 1 Mouthwashes were prepared with the compositions shown in Table 1. The resulting mouthwashes were evaluated for the adsorption capacity of activated carbon and low-temperature stability by the following methods.

[0028] <Adsorption capacity of activated carbon> Methylene blue (0.12 g / 100 ml) was added to each mouthwash to a 100-fold dilution, mixed for 20 seconds, and then the activated carbon was filtered through a filter. The absorbance (644 nm) of the resulting filtrate was measured. As a control, a solution of methylene blue (0.12 g / 100 ml) diluted 100-fold with purified water was also measured for absorbance. The methylene blue adsorption rate was calculated according to the following formula:

number

[0029] <Low temperature stability> After storing each mouthwash at -5°C for one month, the appearance was observed and the low-temperature stability was evaluated according to the following criteria. · Criteria for judging the dispersion stability of activated carbon ○: No freezing of the mouthwash was observed. ×: Freezing of the mouthwash was observed.

[0030] The results are shown in Table 1. When 0.01 wt% activated carbon was used alone, it was not possible to provide low-temperature stability, regardless of whether the average particle size was 5 μm or 25 μm (Comparative Examples 2 and 3). Furthermore, when 0.01 wt% activated carbon with an average particle size of 25 μm was combined with glycerin, propylene glycol, or 1,3-butylene glycol, low-temperature stability was improved, but the adsorption capacity of the activated carbon was reduced (Comparative Examples 5 to 7). Furthermore, when 0.01 wt% activated carbon with an average particle size of 5 μm was combined with 1,3-butylene glycol, the adsorption capacity of the activated carbon was also reduced (Comparative Example 4). In contrast, when 0.01 wt% activated carbon with an average particle size of 5 μm was combined with glycerin or propylene glycol, low-temperature stability was improved and the adsorption capacity of the activated carbon was also excellent (Examples 1 and 2). In particular, when 0.01 wt% activated carbon with an average particle size of 5 μm was used with glycerin, the reduction in the adsorption capacity of the activated carbon was significantly reduced (Example 1).

[0031] [Table 1]

[0032] Prescription example Mouthwashes (Formulation Examples 1 to 6), liquid dentifrices (Formulation Examples 7 and 8), and oral sprays (Formulation Example 9) with the compositions shown below were prepared. The obtained mouthwashes, liquid dentifrices, and oral sprays were evaluated for low-temperature stability and adsorption capacity in the same manner as in Test Example 1. All of them showed improved low-temperature stability and excellent adsorption capacity of activated carbon.

[0033] Prescription example 1 (mouthwash) Ingredients Amount (wt%) Activated carbon (average particle size 5μm) 0.006 Polyoxyethylene (20) hydrogenated castor oil 0.05 Polyoxyethylene (60) hydrogenated castor oil 0.1 l-menthol 0.05 Methyl parahydroxybenzoate 0.05 Glycerin 10 Sodium saccharin 0.01 Ethanol 7 pH adjuster (citric acid, sodium citrate) appropriate amount Purified water remainder Total 100

[0034] Prescription example 2 (mouthwash) Ingredients Amount (wt%) Activated carbon (average particle size 5μm) 0.01 Polyoxyethylene (60) hydrogenated castor oil 0.5 l-menthol 0.1 Methyl parahydroxybenzoate 0.1 Ethyl parahydroxybenzoate 0.05 Glycerin 10 Propylene Glycol 5 Sodium saccharin 0.02 pH adjuster (citric acid, sodium citrate) appropriate amount Purified water remainder Total 100

[0035] Prescription example 3 (mouthwash) Ingredients Amount (wt%) Activated carbon (average particle size 5μm) 0.05 Polyoxyethylene (40) hydrogenated castor oil 1.0 Sodium Lauroyl Methyl Taurate 0.5 l-menthol 0.1 Methyl parahydroxybenzoate 0.1 Ethyl parahydroxybenzoate 0.05 Glycerin 10 Propylene Glycol 8 Sodium saccharin 0.01 pH adjuster (citric acid, sodium citrate) appropriate amount Purified water remainder Total 100

[0036] Prescription example 4 (mouthwash) Ingredients Amount (wt%) Activated carbon (average particle size 3μm) 0.006 Polyoxyethylene (20) hydrogenated castor oil 0.05 Polyoxyethylene (60) hydrogenated castor oil 0.1 l-menthol 0.05 Methyl parahydroxybenzoate 0.05 Glycerin 10 Sodium saccharin 0.01 Ethanol 7 pH adjuster (citric acid, sodium citrate) appropriate amount Purified water remainder Total 100

[0037] Prescription example 5 (mouthwash) Ingredients Amount (wt%) Activated carbon (average particle size 8μm) 0.01 Polyoxyethylene (60) hydrogenated castor oil 0.5 l-menthol 0.1 Methyl parahydroxybenzoate 0.1 Ethyl parahydroxybenzoate 0.05 Glycerin 10 Propylene Glycol 5 Sodium saccharin 0.02 pH adjuster (citric acid, sodium citrate) appropriate amount Purified water remainder Total 100

[0038] Prescription example 6 (mouthwash) Ingredients Amount (wt%) Activated carbon (average particle size 5μm) 0.1 Polyoxyethylene (40) hydrogenated castor oil 1.0 Sodium Lauroyl Methyl Taurate 0.5 l-menthol 0.1 Methyl parahydroxybenzoate 0.1 Ethyl parahydroxybenzoate 0.05 Glycerin 10 Propylene Glycol 8 Sodium saccharin 0.01 pH adjuster (citric acid, sodium citrate) appropriate amount Purified water remainder Total 100

[0039] Prescription example 7 (liquid toothpaste) Ingredients Amount (wt%) Activated carbon (average particle size 5μm) 0.01 Polyoxyethylene (60) hydrogenated castor oil 0.1 Sodium lauryl sulfate 0.1 Cetylpyridinium chloride 0.3 Peppermint fragrance (oil-based ingredient) 0.1 Sorbitol 10 Propylene Glycol 5 Sodium saccharin 0.01 pH adjuster (sodium dihydrogen phosphate, sodium monohydrogen phosphate) appropriate amount Purified water remainder Total 100

[0040] Prescription example 8 (liquid toothpaste) Ingredients Amount (wt%) Activated carbon (average particle size 5μm) 0.01 Polyoxyethylene (20) hydrogenated castor oil 0.8 Polyoxyethylene (40) hydrogenated castor oil 0.8 Cetylpyridinium chloride 0.3 Peppermint fragrance (oil-based ingredient) 0.1 Glycerin 10 Propylene Glycol 5 Sodium saccharin 0.01 pH adjuster (sodium dihydrogen phosphate, sodium monohydrogen phosphate) appropriate amount Purified water remainder Total 100

[0041] Prescription Example 9 (Mouth Spray ) Ingredients Amount (wt%) Activated carbon (average particle size 5μm) 0.01 Polyoxyethylene (60) hydrogenated castor oil 0.1 Polyoxyethylene (20) hydrogenated castor oil 0.05 Peppermint oil (oily component) 0.2 l-menthol 0.05 Ethanol 35 Glycerin 10 Sodium saccharin 0.1 pH adjuster (citric acid, sodium citrate) appropriate amount Purified water remainder Total 100

Claims

1. Activated carbon having an average particle size of 10 μm or less, and glycerin and / or propylene glycol; and A liquid oral composition having an activated carbon content of 0.1 weight% or less.

2. A liquid oral composition as described in claim 1, containing 0.1 to 30 weight% of glycerin and / or propylene glycol.

3. A liquid oral composition described in claim 1 or 2, which is a mouthwash.

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