Powdered water-soluble phenylbenzimidazole sulfonic acid organic salts, process for their preparation and sunscreen cosmetic containing them

Abstract

The present invention relates to a powdered water-soluble phenyl benzimidazole sulfonic acid organic salt, a method for preparing the same, and a sunscreen cosmetic containing the same. The present invention can remove impurities that are not detected by a conventional analysis method by adding crude phenyl benzimidazole sulfonic acid to purified water, adding an organic amine compound under stirring to completely dissolve the same, neutralizing the pH of the dissolved solution, filtering the neutralized solution, concentrating the aqueous solution containing a water-soluble salt of phenyl benzimidazole sulfonic acid under reduced pressure, and precipitating crystals by dropwise addition of an organic solvent. In particular, the handling convenience and stability of phenyl benzimidazole sulfonic acid that is not dissolved in water are improved, and the cosmetic maintains a consistent formulation.

Description

Technical Field

[0001] This invention relates to a powdered water-soluble organic salt of phenylbenzimidazole sulfonic acid, its preparation method, and sunscreen cosmetics containing the same. More specifically, this invention relates to a powdered water-soluble organic salt of phenylbenzimidazole sulfonic acid with improved processing properties, wherein crude phenylbenzimidazole sulfonic acid is dissolved in purified water, and an organic amine compound is added under stirring to achieve complete dissolution. The pH of the solution is neutralized, and the neutralized solution is filtered to obtain an aqueous solution containing the water-soluble salt of phenylbenzimidazole sulfonic acid. This solution is then concentrated under reduced pressure and purified by crystallization with the addition of an organic solvent, thereby removing impurities undetectable by conventional analytical methods, particularly improving the processability of water-insoluble phenylbenzimidazole sulfonic acid; and to a method for producing the organic salt and sunscreen cosmetics containing the organic salt. Background Technology

[0002] Phenylbenzimidazole sulfonic acid (PBSA, C) 13 H 10 N2O3S is a compound widely used in sunscreen products in many countries around the world due to its UVB blocking properties in the 290-340 nm range. It is used as the main ingredient for UV protection in various products such as sunscreens, beauty products, cosmetics, perfumes, skin care products, and even hair care products.

[0003] One of the characteristics of phenylbenzimidazole sulfonic acid (PBSA) is that it spreads easily and evenly on the skin when applied, providing a better texture compared to other ingredients. It also effectively absorbs UVB rays across a wide wavelength range, helping to protect the skin.

[0004] Another characteristic of phenylbenzimidazole sulfonic acid (PBSA) is its high stability; it does not decompose even under prolonged exposure to harmful solar radiation. It also reduces the chemical degradation of other UVB blockers. Its performance is particularly outstanding when used in combination with other UVA blockers. Candidate UVA blockers that can be used in combination include avobenzone, zinc oxide, and titanium dioxide, and it can also be mixed with UV absorbers such as terephthalic acid dicamphor sulfonic acid and Tinosorb.

[0005] However, phenylbenzimidazole sulfonic acid (PBSA) has disadvantages such as low skin absorption and potential reduction in UV protection over time.

[0006] In particular, phenylbenzimidazole sulfonic acid (PBSA) is known to be poorly soluble in water, and therefore can only be used in the form of a soluble salt.

[0007] Therefore, when used in cosmetic compositions, there are inconveniences such as the need to adjust the pH with a neutralizing agent, and the difficulty in obtaining a uniform formulation due to impurities. Furthermore, the inability of conventional analytical methods to completely separate impurities leads to a decline in the quality and stability of the final product.

[0008] To address these issues, research is actively underway to convert PBSA into its salt form. This conversion involves ionizing PBSA by binding protons or specific anions, thereby increasing its water solubility, enhancing skin absorption, and allowing UV-blocking ingredients to remain on the skin for a longer period. Furthermore, the salt form enhances the stability of PBSA by preventing chemical changes caused by sunlight, thus maintaining its sustained UV-blocking performance. Therefore, providing PBSA in its salt form is an important research direction for improving sunscreen performance and extending skin protection.

[0009] Patent Document 1 discloses a cosmetic or pharmaceutical formulation containing a stable phenylbenzimidazole sulfonate, which is neutralized with basic amino acids such as arginine, lysine, ornithine, and histidine, and does not form crystals even at pH 7 or below. Specifically, at pH 7 or below, phenylbenzimidazole sulfonate may precipitate in crystalline form, which can impair the homogeneity of the solution, leading to reduced UV blocking efficiency or uneven skin application. Accordingly, this invention reports a technique to increase the stability of aqueous solutions so that crystals do not precipitate even at pH 7 or below. Therefore, it describes a formulation that is stable even in cosmetic formulations with pH between 5.5 and 7, without crystal precipitation.

[0010] Patent Document 2 relates to a sunscreen cosmetic containing a water-soluble UV absorber, proposing a cosmetic that can both increase SPF and maintain a refreshing feel and good usability. Specifically, it discloses a sunscreen cosmetic containing 0.1% to 5% by weight of phenylbenzimidazole sulfonic acid and an appropriate amount of L-arginine for neutralizing phenylbenzimidazole sulfonic acid. In other words, in order to use phenylbenzimidazole sulfonic acid as a sunscreen cosmetic, it is inevitable to carry out the process of dissolving PBSA in water and then adding an inorganic base such as NaOH or KOH or an organic amino acid, which is both inconvenient and difficult to obtain a consistent formulation. In addition, conventional improvement techniques simply use a neutralization solution, which has limitations in obtaining powdered or high-purity substances.

[0011] Accordingly, as a result of efforts to solve these conventional problems, the inventors used an organic amine compound to completely dissolve phenylbenzimidazole sulfonic acid, neutralize the pH of the solution, then concentrate the aqueous solution containing the neutralized phenylbenzimidazole sulfonic acid water-soluble salt under reduced pressure, and then add an organic solvent dropwise to precipitate crystals, thereby removing impurities undetectable by conventional analytical methods, thus providing a powdered water-soluble phenylbenzimidazole sulfonic acid organic salt, thereby demonstrating the convenience and stability of the formulation and completing the present invention.

[0012] [Related Technical Documents] (Patent Document 1) U.S. Patent No. 8440172 (registered May 14, 2013) (Patent Document 2) Japanese Unexamined Patent Publication No. 2011-111446 (Published on June 9, 2011) Summary of the Invention The purpose of this invention is to provide a powdered, water-soluble organic salt of phenylbenzimidazole sulfonic acid.

[0013] Another object of the present invention is to provide a method for preparing a powdered water-soluble phenylbenzimidazole sulfonic acid organic salt.

[0014] Another object of the present invention is to provide a sunscreen cosmetic containing a powdered, water-soluble organic salt of phenylbenzimidazole sulfonic acid.

[0015] Means for solving the problem To achieve the above objectives, the present invention provides a powdered water-soluble phenylbenzimidazole sulfonic acid organic salt, which is derived from a neutralized solution obtained by adding an organic amine compound to water-insoluble phenylbenzimidazole sulfonic acid.

[0016] Preferably, the organic amine compound may be selected from any one of the group consisting of tromethamine, triethanolamine and 2-amino-2-methyl-1-propanol (AMP).

[0017] As another preferred example, the organic amine compound can be selected from any basic amino acid in the group consisting of arginine, lysine, histidine, and citrulline.

[0018] Furthermore, as another example, organic amine compounds can be selected from polyamines in the group consisting of polyethyleneimine, spermidine, spermine, cadaverine, and putrescine.

[0019] The present invention also provides a method for preparing powdered water-soluble phenylbenzimidazole sulfonic acid organic salt, comprising: adding crude phenylbenzimidazole sulfonic acid to purified water, adding an organic amine compound while stirring to completely dissolve it; neutralizing the pH of the dissolved solution; filtering the neutralized solution to obtain an aqueous solution containing phenylbenzimidazole sulfonic acid organic salt; concentrating the aqueous solution under reduced pressure; then adding an organic solvent dropwise to precipitate and purify the crystals.

[0020] In the manufacturing process, crude phenylbenzimidazole sulfonic acid and organic amine compounds are added in a stoichiometric ratio of 1:1.

[0021] In the manufacturing method, according to the liquid chromatography detection method, the step of neutralizing the solution pH is to adjust the pH to 7 by mixing the mobile phase with a 1% triethylamine (TEA) solution and then using phosphoric acid.

[0022] In addition, in the manufacturing method, the aqueous solution is concentrated to the volume level of the initial purified water under reduced pressure, and then an organic solvent is added dropwise to precipitate the crystals.

[0023] In the above, the organic amine compound can be selected from any one of the group consisting of tromethamine, triethanolamine and 2-amino-2-methyl-1-propanol (AMP). As another example, the organic amine compound can be selected from any one of the basic amino acids in the group consisting of arginine, lysine, histidine and citrulline.

[0024] Furthermore, as another example, the organic amine compound can be any polyamine selected from the group consisting of polyethyleneimine, spermidine, spermine, cadaverine, and putrescine.

[0025] In addition, the present invention also provides a sunscreen cosmetic containing a powdered water-soluble organic salt of phenylbenzimidazole sulfonic acid.

[0026] Inventive effect According to the present invention, the powdered, water-soluble organic salt of phenylbenzimidazole sulfonic acid, when used in sunscreen cosmetics, eliminates the need for the neutralization step of dissolving the water-insoluble phenylbenzimidazole sulfonic acid in water and adding an inorganic base such as NaOH or KOH or an organic amino acid. By providing a powdered, water-soluble salt, the convenience and stability of the formulation in handling are improved.

[0027] Therefore, according to the present invention, various phenylbenzimidazole sulfonates obtained in powder form as neutralization products of strongly acidic and insoluble phenylbenzimidazole sulfonic acid and organic amines can achieve consistent formulations in cosmetic formulations.

[0028] Furthermore, according to the manufacturing method of the present invention, a high-purity powdered water-soluble phenylbenzimidazole sulfonic acid organic salt can be provided, wherein impurities undetectable by conventional analytical methods have been removed, and cosmetics can be produced without a separate neutralizing agent, making it convenient and safe, and ensuring long-term storage stability. Attached Figure Description

[0029] Figure 1 The HPLC results of crude phenylbenzimidazole sulfonic acid, which was used as a starting material in Example 1 of the present invention, are shown.

[0030] Figure 2 The HPLC results of phenylbenzimidazole sulfonic acid-aminobutyric acid obtained in Example 1 of this invention are shown.

[0031] Figure 3 yes Figure 2 Photograph of crystalline form of phenylbenzimidazole sulfonic acid-aminobutyric acid. Detailed Implementation

[0032] The present invention will now be described in detail.

[0033] The present invention provides a powdered water-soluble phenylbenzimidazole sulfonic acid organic salt, which is derived from a neutralized solution obtained by adding an organic amine compound to water-insoluble phenylbenzimidazole sulfonic acid.

[0034] More specifically, a powdered, water-soluble organic salt of phenylbenzimidazole sulfonic acid is provided as a crystalline precipitate.

[0035] Salt forms can typically be used for bioderived amines, basic amino acids, organic amine-based compounds used as cosmetic ingredients, organic amine-based compounds used as plant additives, and organic amine-based compounds used as pharmaceuticals.

[0036] Preferably, any organic amine compound used in cosmetic ingredients is used as an organic amine chemical, with preferred examples including basic organic compounds such as secondary or tertiary amines, polyamines, and urea.

[0037] As a preferred example, the organic amine compound used in this invention may be selected from any one of the group consisting of tromethamine, triethanolamine, and 2-amino-2-methyl-1-propanol (AMP).

[0038] In addition, the organic amine compound can be selected from any basic amino acid in the group consisting of arginine, lysine, histidine, and citrulline.

[0039] In addition, the organic amine compound can be any polyamine selected from the group consisting of polyethyleneimine, spermidine, spermine, cadaverine, and putrescine.

[0040] The powdered water-soluble phenylbenzimidazole sulfonic acid organic salt of the present invention, by using an organic amine designated as a pharmaceutical raw material, food additive raw material or cosmetic raw material, can also ensure the safety of the final target compound to the human body based on the stability of the raw material.

[0041] In particular, the powdered water-soluble phenylbenzimidazole sulfonic acid organic salt of the present invention provides various phenylbenzimidazole sulfonates obtained in powder form as neutralization products of strongly acidic and insoluble phenylbenzimidazole sulfonic acid and organic amines, thereby improving the convenience and stability of formulations according to the treatment and keeping cosmetic formulations consistent.

[0042] Furthermore, the present invention also provides a method for manufacturing the above-mentioned powdered water-soluble phenylbenzimidazole sulfonic acid organic salt.

[0043] More specifically, a method for preparing a powdered water-soluble organic salt of phenylbenzimidazole sulfonic acid is provided, comprising: 1) Add crude phenylbenzimidazole sulfonic acid to purified water, along with an organic amine compound, and stir until completely dissolved. 2) Neutralize the pH of the solution; and 3) Filter the neutralized solution to obtain an aqueous solution containing the water-soluble salt of phenylbenzimidazole sulfonic acid. Concentrate the aqueous solution under reduced pressure, then add an organic solvent dropwise to precipitate and purify the crystals.

[0044] In addition, a drying step may be performed after step 3).

[0045] In the manufacturing method of the present invention, in step 1), crude phenylbenzimidazole sulfonic acid and an organic amine compound are added in a stoichiometric ratio of 1:1 to obtain a salt form.

[0046] Salt forms can typically be used for bioderived amines, basic amino acids, organic amine-based compounds used as cosmetic ingredients, organic amine-based compounds used as plant additives, and organic amine-based compounds used as pharmaceuticals.

[0047] Preferably, any organic amine compound used in cosmetic ingredients is used as an organic amine chemical, with preferred examples including basic organic compounds such as secondary or tertiary amines, polyamines, and urea.

[0048] As a preferred example, the organic amine compound used in this invention may be selected from any one of the group consisting of tromethamine, triethanolamine, and 2-amino-2-methyl-1-propanol (AMP).

[0049] In addition, the organic amine compound can be selected from any basic amino acid in the group consisting of arginine, lysine, histidine, and citrulline.

[0050] In addition, the organic amine compound can be any polyamine selected from the group consisting of polyethyleneimine, spermidine, spermine, cadaverine, and putrescine.

[0051] The phenylbenzimidazole sulfonic acid organic salt of the present invention, by using an organic amine designated as a pharmaceutical raw material, food additive raw material or cosmetic raw material, can also ensure the safety of the final target compound to the human body based on the stability of the raw material.

[0052] Specifically, the present invention relates to a water-soluble phenylbenzimidazole sulfonic acid organic salt, which is obtained by combining an organic amine compound with the end of phenylbenzimidazole sulfonic acid in a stoichiometric ratio of 1:1 as a neutralization product at a pH of 6.8-7.5.

[0053] In the embodiments of the present invention, tromethamine of chemical formula 1 or arginine of chemical formula 2 were used for illustration, but the present invention is not limited thereto.

[0054] Chemical Formula 1 Chemical formula 2 In the manufacturing method of the present invention, step 2) includes neutralizing the pH of the solution obtained in step 1).

[0055] Typically, when organic amine compounds are stoichiometrically combined with the terminal of phenylbenzimidazole sulfonic acid, a neutral substance with a pH of 6.8-7.5 is formed. However, commercially available phenylbenzimidazole sulfonic acid with a purity of 98% contains impurities.

[0056] According to the Korean Standards and Test Methods for Functional Cosmetics (Article 2, Paragraph 4, Item 4) regarding the regulations for functional cosmetics that help protect the skin from UV damage [Appendix 4], the content of phenylbenzimidazole sulfonic acid was analyzed.

[0057] The following is a citation: Accurately weigh approximately 25 mg of this raw material, dissolve it in 10 mL of 1N sodium hydroxide solution, and then dilute to 250 mL with methanol to prepare the test solution. Separately, accurately weigh approximately 25 mg of phenylbenzimidazole sulfonic acid standard and prepare a standard solution using the same method as the test solution. Take 10 μL each of the test solution and standard solution and perform detection by liquid chromatography under the following conditions to determine the peak area A of phenylbenzimidazole sulfonic acid. T and A S .

[0058] Phenylenic acid benzimidazole sulfonic acid (C 13 H 10 The amount of N2O3S (mg) = the amount of phenylbenzimidazole sulfonic acid standard (mg) × (A T / AS ) Operating conditions: Detector: UV spectrophotometer (measurement wavelength: 305 nm) Column: A stainless steel tube with an inner diameter of 4.6 mm and a length of 15 cm is packed with 5 μm of octadecylsilane-modified silica gel. Column temperature: 40℃ Mobile phase: a mixture of dilute acetic acid (1→10,000) and methanol (20:80). Flow rate: 0.3 mL / min, follow the instructions.

[0059] On the other hand, although the United States Pharmacopeia (USP44) has established a standard under the name Ensulizole, when analyzed according to the Korean domestic (KP) standard, the peak appears early and the impurities and target substances are not separated, making it impossible to identify the existing impurities.

[0060] Furthermore, the USP specification uses titration, which makes it difficult to accurately identify impurities.

[0061] To address this issue, in order to identify impurities present in phenylbenzimidazole sulfonic acid, a mobile phase conforming to Korean domestic (KP) standards was modified. This was achieved by mixing the mobile phase with a 1% triethylamine solution (triethylamine: ultrapure water = 1:100 v / v), adjusting the pH to 7 with phosphoric acid, and then performing the remaining steps in the same manner.

[0062] In the manufacturing method of the present invention, step 3) includes filtering the neutralized solution of step 2) to obtain a clear aqueous solution containing phenylbenzimidazole sulfonic acid organic salt, concentrating the clear aqueous solution under reduced pressure, then adding an organic solvent dropwise to precipitate and purify the crystals.

[0063] The clarified aqueous solution was concentrated under reduced pressure to the volume level of the purified water used in step 1), and then an organic solvent was added dropwise to induce crystal precipitation.

[0064] In embodiments of the present invention, acetone is used as an organic solvent, but the invention is not limited thereto. Preferably, the process is carried out under reduced pressure at a volume ratio of 1:10 between the concentrated aqueous solution and the organic solvent.

[0065] Figure 1 The HPLC results of crude phenylbenzimidazole sulfonic acid, used as the starting material in Example 1 of this invention, are shown. Small peaks indicate trace impurities or residual solvents. Figure 2The HPLC results of phenylbenzimidazole sulfonic acid-tromethamine obtained according to this method are shown. A single peak was observed, and the retention time of the peak was shortened due to the binding of tromethamine with phenylbenzimidazole sulfonic acid, confirming that tromethamine affects the molecular properties of phenylbenzimidazole sulfonic acid.

[0066] Therefore, it can be confirmed that the phenylbenzimidazole sulfonic acid-tromethamine obtained according to the method of the present invention is in a high purity state, with almost no impurities detected.

[0067] Figure 3 It comes from Figure 2 A photograph of phenylbenzimidazole sulfonic acid-aminobutyric acid in crystalline form was taken, confirming the powder form.

[0068] In summary, the manufacturing method of the present invention can provide various high-purity phenylbenzimidazole sulfonates in powder form, thereby enabling cosmetics to maintain consistent formulations.

[0069] Furthermore, the present invention also provides a sunscreen cosmetic containing a powdered, water-soluble organic salt of phenylbenzimidazole sulfonic acid obtained by the manufacturing method.

[0070] These cosmetic products can be used without particular restrictions on any product category that requires UV protection, including sunscreens, beauty products, cosmetics, perfumes, skin care products, and hair care products.

[0071] The present invention will now be described in more detail through embodiments. These embodiments are intended to illustrate the invention in more detail, but the scope of the invention is not limited to these embodiments.

[0072] <Example 1> 100 g (0.3646 mol) of phenylbenzimidazole sulfonic acid with a purity of 98.71% and 150 mL of purified water were placed in a 3L four-necked round-bottom flask. 44.168 g (0.3646 mol) of tromethamine was added with stirring until completely dissolved. The pH of the solution was adjusted to 7.0. The solution was filtered through filter paper to obtain a clear aqueous solution containing phenylbenzimidazole sulfonic acid-tromethamine as shown in formula 1-1.

[0073] According to the Korean domestic (KP) regulations [Standards and Test Methods for Functional Cosmetics, Appendix 4], the mobile phase was mixed with a 1% triethylamine solution (triethylamine: ultrapure water = 1:100 v / v), and then the pH of the solution was adjusted to 7 with phosphoric acid.

[0074] Therefore, the impurities present in phenylbenzimidazole sulfonic acid can be removed.

[0075] Chemical Formula 1-1 The obtained phenylbenzimidazole sulfonic acid-tromethamine aqueous solution was concentrated to a volume of 150 mL under reduced pressure, and then 1500 mL of acetone was slowly added dropwise at room temperature for 30 minutes, while crystals precipitated.

[0076] Continue stirring for another 2 hours until the crystals are completely precipitated. Then filter and wash to obtain phenylbenzimidazole sulfonic acid-tromethamine crystals, which are dried under vacuum to obtain 136.92 g of the target compound in powder form (yield 95%, purity 100%).

[0077] <Example 2> Place 100 g (0.3646 mol) of phenylbenzimidazole sulfonic acid with a purity of 98.71% and 150 mL of purified water in a 3L four-necked round-bottom flask. Add 63.463 g (0.3646 mol) of arginine with stirring until it is completely dissolved, and adjust the pH of the solution to 7.0.

[0078] The solution was filtered through filter paper to obtain a clear aqueous solution containing phenylbenzimidazole sulfonic acid-arginine.

[0079] The obtained phenylbenzimidazole sulfonic acid-arginine aqueous solution was concentrated to a volume of 150 mL under reduced pressure, and then 1500 mL of acetone was slowly added dropwise at room temperature for 30 minutes, while crystals precipitated.

[0080] Continue stirring for another 2 hours until the crystals are completely precipitated. Then filter and wash to obtain the target phenylbenzimidazole sulfonic acid-arginine crystals, which are dried under vacuum to obtain 155.29 g of the target compound in powder form (yield 95%, purity 100%).

[0081] <Experimental Example 1> Spectroscopic Evaluation According to the Korean Standards and Test Methods for Functional Cosmetics (Article 2, Paragraph 4, Item 4) regarding functional cosmetics that help protect the skin from UV damage [Appendix 4], the content of phenylbenzimidazole sulfonic acid and phenylbenzimidazole sulfonic acid-tromethamine in each stage of Example 1 was analyzed.

[0082] At this time, the implementation method of liquid chromatography detection is the same in the notified Korean domestic (KP) specifications, except for the modification of the mobile phase. By mixing with a 1% triethylamine solution (triethylamine: ultrapure water = 1:100 v / v) and then adjusting the pH to 7 with phosphoric acid, the impurities present in phenylbenzimidazole sulfonic acid are identified and removed through this pH adjustment.

[0083] Figure 1The HPLC results of crude phenylbenzimidazole sulfonic acid, which was used as the starting material in Example 1, are shown. A relatively high concentration of the main peak at 15.619 min was identified as phenylbenzimidazole sulfonic acid, while the small peaks at 8.073 min, 13.021 min and 24.503 min appear to be trace impurities or residual solvents.

[0084] on the other hand, Figure 2 The HPLC results of the phenylbenzimidazole sulfonic acid-tromethamine obtained in Example 1 are shown, with a single peak observed at 14.931 min. The peak position confirms that the retention time decreases with the binding of tromethamine to phenylbenzimidazole sulfonic acid, indicating that tromethamine affects the molecular properties of phenylbenzimidazole sulfonic acid.

[0085] Furthermore, it was confirmed that phenylbenzimidazole sulfonic acid-tromethamine contains almost no detectable impurities and exists in a high-purity state.

[0086] Although the present invention has been described in detail only with respect to specific embodiments, it will be apparent to those skilled in the art that various modifications and alterations can be made within the scope of the technical spirit of the present invention, and such modifications and alterations naturally fall within the scope of the appended claims.

Claims

1. A powdered, water-soluble organic salt of phenylbenzimidazole sulfonic acid, derived from a neutralized solution obtained by adding an organic amine compound to water-insoluble phenylbenzimidazole sulfonic acid.

2. The powdered water-soluble phenylbenzimidazole sulfonic acid organic salt according to claim 1, wherein the organic amine compound is selected from any one of the group consisting of tromethamine, triethanolamine and 2-amino-2-methyl-1-propanol (AMP).

3. The powdered water-soluble phenylbenzimidazole sulfonic acid organic salt according to claim 1, wherein the organic amine compound is selected from any one basic amino acid in the group consisting of arginine, lysine, histidine and citrulline.

4. The powdered water-soluble phenylbenzimidazole sulfonic acid organic salt according to claim 1, wherein the organic amine compound is selected from any polyamine in the group consisting of polyethyleneimine, spermidine, spermine, cadaverine, and putrescine.

5. A method for preparing powdered water-soluble phenylbenzimidazole sulfonic acid organic salt, comprising: Crude phenylbenzimidazole sulfonic acid was added to purified water, and an organic amine compound was added under stirring to completely dissolve it. Neutralize the pH of the solution; The neutralized solution was filtered to obtain an aqueous solution containing the organic salt of phenylbenzimidazole sulfonic acid; the aqueous solution was concentrated under reduced pressure; an organic solvent was added dropwise to precipitate and purify the crystals.

6. The method for preparing powdered water-soluble phenylbenzimidazole sulfonic acid organic salt according to claim 5, wherein the crude phenylbenzimidazole sulfonic acid and the organic amine compound are added in a stoichiometric ratio of 1:

1.

7. The method for preparing powdered water-soluble phenylbenzimidazole sulfonic acid organic salt according to claim 5, The liquid chromatography detection method involves mixing the mobile phase with a 1% triethylamine (TEA) solution and then adjusting the pH to 7 with phosphoric acid to neutralize the solution pH.

8. The method for preparing powdered water-soluble phenylbenzimidazole sulfonic acid organic salt according to claim 5, wherein the aqueous solution is concentrated to the volume level of the initial purified water under reduced pressure, and then an organic solvent is added dropwise to precipitate crystals.

9. The method for preparing powdered water-soluble phenylbenzimidazole sulfonic acid organic salt according to claim 5, wherein the organic amine compound is selected from any one of the group consisting of tromethamine, triethanolamine and 2-amino-2-methyl-1-propanol (AMP).

10. The method for preparing powdered water-soluble phenylbenzimidazole sulfonic acid organic salt according to claim 5, wherein the organic amine compound is selected from the group consisting of basic amino acids of arginine, lysine, histidine and citrulline.

11. The method for preparing powdered water-soluble phenylbenzimidazole sulfonic acid organic salt according to claim 5, wherein the organic amine compound is selected from any polyamine in the group consisting of polyethyleneimine, spermidine, spermine, cadaverine, and putrescine.

12. A sunscreen cosmetic containing a powdered, water-soluble organic salt of phenylbenzimidazole sulfonic acid according to any one of claims 1 to 4.

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