Organic salt of terephthalylidene dicamphorsulfonic acid for sunscreen cosmetics and method for producing the same

Abstract

The present invention relates to an organic salt of terephthalylidene dicamphorsulfonic acid useful for sunscreen cosmetics and a method for producing the same. The present invention provides an organic salt of terephthalylidene dicamphorsulfonic acid in the form of an aqueous solution or powder, which is obtained as a neutralized product of pH 5.0 to 9.0 by binding an organic amine compound to an aqueous solution of terephthalylidene dicamphorsulfonic acid having a strong acidity of pH 1. This makes it possible to produce cosmetics without using a separate neutralizing agent, is convenient and safe, and has excellent long-term storage stability, enabling consistent formulation in cosmetic formulations in particular.

Description

[Technical Field]

[0001] The present invention relates to an organic salt of terephthalylidene dicamphorsulfonic acid, which is useful for sunscreen cosmetics, and a method for producing the same. More specifically, the present invention relates to an organic salt of terephthalylidene dicamphorsulfonic acid, which is obtained as a neutralized product at pH 5.0 to 9.0 by binding an organic amine compound to an aqueous solution of terephthalylidene dicamphorsulfonic acid having a strong acidity of pH 1, and which is provided in the form of an aqueous solution or powder. This enables the production of cosmetics without using a separate neutralizing agent, and is convenient and safe, ensures long-term storage stability, and enables consistent formulation in cosmetic formulations. The present invention also relates to an organic salt of terephthalylidene dicamphorsulfonic acid, which is useful for sunscreen cosmetics, and a method for producing the same. [Background technology]

[0002] Due to the destruction of the ozone layer caused by climate change, ultraviolet rays directly hit human skin, causing skin blemishes and skin aging, making sunscreens essential in cosmetics, and sunscreens (ultraviolet blockers) are widely used in cosmetics.

[0003] In particular, UV-B, with wavelengths of 280 to 320 nm, causes redness of the skin (erythema), while UV-A, with wavelengths of 320 to 400 nm, causes skin browning, damages the skin, and is a cause of skin cancer.

[0004] Furthermore, with regard to sunscreens that are applied to the skin, regulations regarding safety and irritation to the skin are currently being strengthened in countries around the world.

[0005] When ultraviolet light hits a sunscreen, it absorbs the ultraviolet light energy and converts it into heat energy. In other words, the light is absorbed and its life as light ends before it is converted into heat. The ultraviolet light is absorbed by the sunscreen and is blocked from reaching the skin, protecting the skin.

[0006] Currently, terephthalylidene dicamphorsulfonic acid (TDSA, known as "Ecamsule" in the United States Pharmacopoeia) is a sunscreen approved by the US FDA (Food and Drug Administration) for its ability to block UV-A rays in the wavelength range of 320 to 400 nm.

[0007] As the need for UV protection increases day by day, the market for terephthalylidene dicamphorsulfonic acid is expanding, and its applications are expanding not only in cosmetics but also in various fields such as hair rinses and medicines.

[0008] Patent Documents 1 and 2 disclose methods for synthesizing terephthalylidene dicamphorsulfonic acid. However, it is difficult to remove charged organic impurities, phosphorus chloride, sulfate ions, chloride ions, heavy metals, sodium, and the like that are generated in the synthesis process of terephthalylidene dicamphorsulfonic acid using only the known synthesis techniques.

[0009] Therefore, in order to solve the problems of the known synthesis methods, Patent Document 3 discloses a method for purifying terephthalylidene dicamphorsulfonic acid, in which a mixed resin containing cations and anions is used in the synthesis and precipitation processes of terephthalylidene dicamphorsulfonic acid, thereby improving absorbance at the maximum absorption wavelength in ultraviolet spectroscopic analysis and removing cationic and anionic substances generated in the synthesis and precipitation processes to purify the acid.

[0010] However, since terephthalylidene dicamphorsulfonic acid itself has a strong acidity of pH 1 or less, a neutralizer is required for use in cosmetic compositions, which poses troublesome and safety issues requiring user caution. In particular, even when a neutralizer is used, problems arise, such as the need to correct pH and inconsistent formulation in cosmetic formulations.

[0011] Furthermore, since the strongly acidic terephthalylidene dicamphorsulfonic acid itself has a pH of 1 or less, it is left under acidic conditions for a long period of time, which causes a problem of a decrease in purity over time.

[0012] Therefore, the present inventors have made efforts to solve such problems with terephthalylidene dicamphorsulfonic acid used as a sunscreen in cosmetics. As a result, they have confirmed that by adding an organic amine used in cosmetics to an aqueous solution of terephthalylidene dicamphorsulfonic acid having a strong acidity of pH 1 to adjust the pH of the solution to a range of 5.0 to 9.0, and providing an organic salt of terephthalylidene dicamphorsulfonic acid in the form of an aqueous solution or powder, cosmetics can be manufactured without using a separate neutralizing agent, which is convenient, safe, and enables the formulation of consistent cosmetic formulations while ensuring long-term storage stability, thereby completing the present invention. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] U.S. Patent Publication No. 4,585,597 (published April 29, 1986) [Patent Document 2] China Patent No. 106831503 (Published June 13, 2017) [Patent Document 3] Korean Patent No. 10-1937332 (published on January 11, 2019) Summary of the Invention [Problem to be solved by the invention]

[0014] The object of the present invention is to provide a compound in which terephthalylidene dicamphorsulfonic acid having strong acidity and an organic amine compound are stoichiometrically bonded. Neutralized substance The present invention provides an organic salt of terephthalylidene dicamphorsulfonic acid which satisfies convenience and safety during the production of cosmetics.

[0015] Another object of the present invention is to provide a method for preparing an organic salt of terephthalylidene dicamphorsulfonic acid in the form of an aqueous solution or a powder.

[0016] A further object of the present invention is to provide a sunscreen cosmetic composition containing the organic salt of terephthalylidene dicamphorsulfonic acid. [Means for solving the problem]

[0017] In order to achieve the above object, the present invention provides an organic salt of terephthalylidene dicamphorsulfonic acid represented by the following chemical formula 1, which is useful for sunscreen cosmetics and is obtained as a neutralized product having a pH of 5.0 to 9.0 by stoichiometrically bonding an organic amine compound to both ends of terephthalylidene dicamphorsulfonic acid.

[0018] [ka]

[0019] In the formula, R1, R2, and R3 may be the same or different, and each independently represents a hydrogen atom, a hydroxy group, an amino group, a carboxy group, a C1-C 10 Alkyl groups, C1-C 10 Hydroxyalkyl groups, C1-C 10 C1-C groups including heteroalkyl groups, heterocycloalkyl groups having 20 or less carbon atoms, aryl groups having 20 or less carbon atoms, and heterocycloalkyl groups having 20 or less carbon atoms. 10 C1-C, including alkyl groups and aryl groups with 20 or less carbon atoms 10 It may be substituted with one or more substituents selected from the group consisting of alkyl groups.

[0020] As the organic amine compound, preferably, any one selected from the group consisting of tromethamine, triethanolamine, and 2-amino-2-methyl-1-propanol (AMP) may be used.

[0021] Another preferred type of organic amine compound may be any one basic amino acid selected from the group consisting of arginine, lysine, histidine, citrulline, and amino acid derivatives in which the carboxyl group of the amino acid is substituted to leave only the primary amine group.

[0022] Furthermore, as still another type of preferred organic amine compound, any one polyamine selected from the group consisting of polyethyleneimine, spermidine, spermine, cadaverine and putrescine may be used.

[0023] The organic salt of terephthalylidene dicamphorsulfonic acid may be provided in the form of an aqueous solution or a powder, thereby providing convenience and safety during the preparation of cosmetics.

[0024] The present invention provides a method for preparing an organic salt of terephthalylidene dicamphorsulfonic acid.

[0025] Specifically, the present invention provides a method for producing an organic salt of terephthalylidene dicamphorsulfonic acid, which is obtained as a clear aqueous solution by dissolving an organic amine compound in a purified aqueous solution of terephthalylidene dicamphorsulfonic acid, adjusting the pH of the solution, and then filtering the solution.

[0026] The production method of the present invention may further include a step of adding the obtained clear aqueous solution dropwise to an organic solvent to precipitate crystals, and then vacuum drying the crystals to obtain them in powder form.

[0027] Furthermore, the production method of the present invention may further include a step of freeze-drying the obtained clear aqueous solution to obtain a powder.

[0028] In this case, when the organic salt of terephthalylidene dicamphorsulfonic acid is in the form of an aqueous solution, it may further contain one or more preservatives selected from the group consisting of 1,2-alkanediol, ethylhexylglycerin, hydroxyacetophenone, glycerin esters, parabens, and sodium benzoate, thereby maintaining the dosage form. [Effects of the Invention]

[0029] According to the present invention, an organic salt of terephthalylidene dicamphorsulfonic acid is provided, which is obtained by neutralizing terephthalylidene dicamphorsulfonic acid having strong acidity with an organic amine compound. This makes it possible to produce cosmetics without using a separate neutralizing agent, which is convenient and safe, ensures long-term storage stability, and enables consistent formulation of cosmetics.

[0030] According to the production method of the present invention, an organic salt of terephthalylidene dicamphorsulfonic acid can be provided in the form of an aqueous solution or a powder. [Brief explanation of the drawings]

[0031] [Figure 1] 1 shows the IR spectrum of terephthalylidene dicamphorsulfonic acid·2-tromethamine of the present invention. [Figure 2] 1 is a photograph of an aqueous solution of terephthalylidene dicamphorsulfonic acid·2-tromethamine of the present invention. [Figure 3] 1 is a photograph of the crystals of terephthalylidene dicamphorsulfonic acid·2-tromethamine of the present invention. [Figure 4] 1 is a photograph of the powder form of terephthalylidene dicamphorsulfonic acid·2-tromethamine of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0032] The present invention provides a method for producing a terephthalylidene dicamphorsulfonic acid having an organic amine compound stoichiometrically bonded to both ends thereof at a pH of 5.0 to 9.0. Neutralized substance The present invention provides an organic salt of terephthalylidene dicamphorsulfonic acid represented by the following chemical formula 1, which is obtained by:

[0033] [ka]

[0034] In the formula, R1, R2, and R3 may be the same or different, and each independently represents a hydrogen atom, a hydroxy group, an amino group, a carboxy group, a C1-C 10 Alkyl groups, C1-C 10 Hydroxyalkyl groups, C1-C 10 C1-C groups including heteroalkyl groups, heterocycloalkyl groups having 20 or less carbon atoms, aryl groups having 20 or less carbon atoms, and heterocycloalkyl groups having 20 or less carbon atoms. 10 C1-C, including alkyl groups and aryl groups with 20 or less carbon atoms 10 It may be substituted with one or more substituents selected from the group consisting of alkyl groups.

[0035] Terephthalylidene dicamphorsulfonic acid is used as a cosmetic raw material for blocking ultraviolet rays due to its ability to block rays in the wavelength range of 320 to 400 nm known as UV-A. In order to solve the problems caused by the strong acidity of terephthalylidene dicamphorsulfonic acid, it is provided in the form of a salt thereof, thereby ensuring safety during use and providing convenience in operations, and as a result, a cosmetic composition having stable ultraviolet blocking ability is provided.

[0036] The organic amine compound to be formed into the salt form may be an organic amine compound used in cosmetic compositions, a basic amino acid, an amine derived from a living organism, an organic amine compound used as a food additive, or an organic amine compound used as a pharmaceutical.

[0037] In the organic salt of terephthalylidene dicamphorsulfonic acid of the present invention, the salt is an organic amine compound designated for use as a pharmaceutical raw material, a food additive raw material, or a cosmetic raw material, so that not only the stability of the raw material but also the stability of the final target compound in the human body is ensured.

[0038] Specifically, in the present invention, an organic amine compound used in a cosmetic composition is used in the form of an organic salt of terephthalylidene dicamphorsulfonic acid obtained as a neutralized product at pH 5.0 to 9.0, preferably pH 6.1 to 8.0, in which terephthalylidene dicamphorsulfonic acid and an organic amine compound are combined at an equivalent ratio of 1:2.

[0039] In the embodiments of the present invention, tromethamine, triethanolamine, or 2-Amino-2-methyl-1-propanol (AMP) will be used as preferred examples for explanation, but the present invention is not limited to these.

[0040] As another organic amine compound, a basic amino acid may be used, which may be any one selected from the group consisting of arginine, lysine, histidine, citrulline, and amino acid derivatives in which the carboxyl group of the amino acid is substituted to leave only the primary amine group. In the above, an example of an amino acid derivative in which the carboxyl group of the amino acid is substituted to leave only the primary amine group may be N-acetyl-glutamine isostearyl.

[0041] In the embodiments of the present invention, arginine, lysine and histidine are used for explanation, but the present invention is not limited thereto.

[0042] The organic amine compound of the present invention may preferably be a polyamine, more preferably any one selected from the group consisting of polyethyleneimine (PEI), spermidine, spermine, cadaverine, and putrescine.

[0043] Polyethyleneimine is the best known polyamine, has the highest cation density of any existing material, and is a particularly water-soluble polymer.

[0044] Spermidine is also found in various foods such as soybeans, wheat, and meat, spermine is a polyamine with a similar structure to spermidine that performs various physiological functions within cells, cadaverine is a polyamine named after its discovery in rotten meat, and putrescine is also a biologically derived polyamine found in various organisms.

[0045] The organic amine compound is bonded to terephthalylidenedicamphorsulfonic acid in a stoichiometric ratio of two equivalents to form an organic salt of terephthalylidenedicamphorsulfonic acid.

[0046] FIG. 1 shows the IR spectrum of the terephthalylidene dicamphorsulfonic acid·2-tromethamine organic salt of the present invention, and the synthesis of the organic salt can be confirmed.

[0047] The organic salt of terephthalylidene dicamphorsulfonic acid of the present invention may be provided in the form of an aqueous solution or powder depending on the desired formulation during the production of cosmetics. Since it is provided in the form of a stable salt, no additional neutralizing agent is required during the production of cosmetics, which is convenient and safe, and enables consistent formulation in cosmetic formulations.

[0048] Furthermore, the organic salt of terephthalylidene dicamphorsulfonic acid obtained by the production method of the present invention also has long-term stability.

[0049] The present invention provides a method for producing an organic salt of terephthalylidene dicamphorsulfonic acid according to a first embodiment, which comprises dissolving a basic organic amine in a purified aqueous solution of terephthalylidene dicamphorsulfonic acid at a temperature of 30°C or less, adjusting the pH of the solution, and then filtering the solution through a microfilter to obtain a clear aqueous solution.

[0050] At this time, the pH of the organic salt of terephthalylidene dicamphorsulfonic acid is adjusted so as to finally be in the range of 5.0 to 9.0, most preferably in the range of 6.1 to 8.0.

[0051] An aqueous solution containing a stable dosage form of the terephthalylidene dicamphorsulfonic acid organic salt may be provided.

[0052] As an example, Figure 2 is a photograph of an aqueous solution of terephthalylidene dicamphorsulfonic acid·2-tromethamine in Example 1. A neutral solution of the organic salt of terephthalylidene dicamphorsulfonic acid is more stable than an acidic solution of terephthalylidene dicamphorsulfonic acid, and in particular, since it is a neutral solution, the use of a preservative such as 1,2-hexanediol prevents spoilage and improves stability.

[0053] In this case, the aqueous solution may further contain one or more preservatives selected from the group consisting of 1,2-alkanediol, ethylhexylglycerin, hydroxyacetophenone, glycerin esters, parabens, and sodium benzoate. The addition of the preservatives can improve the formulation stability of the salt.

[0054] More specifically, by using 1 to 2.5% by weight of 1,2-hexanediol, 1 to 5% by weight of 1,2-pentanediol, 0.1 to 1% by weight of 1,2-octanediol, and 0.1 to 1% by weight of ethylhexylglycerin, either individually or in combination, relative to the weight of the obtained organic salt of terephthalylidene dicamphorsulfonic acid, the storage stability of the aqueous solution of the organic salt of terephthalylidene dicamphorsulfonic acid can be improved.

[0055] In the production method of the second embodiment of the present invention, a clear aqueous solution of the organic salt of terephthalylidene dicamphorsulfonic acid obtained in the first embodiment is prepared, and the aqueous solution is dropped into a four-fold volume of an organic solvent such as alcohol, acetone, or a mixture thereof to precipitate crystals. The crystals are filtered, dried, and vacuum-dried to obtain a powder.

[0056] FIG. 3 is a photograph of the crystals of terephthalylidene dicamphorsulfonic acid 2-tromethamine of the present invention. 100 g of the clear aqueous solution of the organic salt of terephthalylidene dicamphorsulfonic acid obtained in the first embodiment is slowly added dropwise to a four-necked round-bottom flask containing 100 to 500 ml of alcohol, acetone, or a mixed solvent thereof with stirring to precipitate the salt. The precipitated crystals are filtered, washed with acetone, and vacuum dried to obtain the organic salt of terephthalylidene dicamphorsulfonic acid tromethamine.

[0057] In addition, in the production method of the third embodiment of the present invention, a clear aqueous solution of the organic salt of terephthalylidene dicamphorsulfonic acid obtained in the first embodiment is prepared, and the aqueous solution is freeze-dried to obtain a powder.

[0058] Figure 4 shows the powder form of terephthalylidene dicamphorsulfonic acid·2-thromethamine of the present invention. As described above, the present invention provides a variety of forms, such as the aqueous solution obtained from the method for producing an organic salt of terephthalylidene dicamphorsulfonic acid, as it is, or as a crystalline form by precipitating the aqueous solution in an organic solvent, or as a powder by freeze-drying, which can be selectively used depending on the desired dosage form when producing cosmetics.

[0059] In particular, the crystalline form of the organic salt of terephthalylidene dicamphorsulfonic acid exists as a solid, and is therefore more stable than an acidic liquid or a neutral solution, and can be stored for a long period of time even at a high temperature such as 45°C.

[0060] The manufacturing method of the present invention can overcome the disadvantages of the conventionally used terephthalylidene dicamphorsulfonic acid, such as product stability problems due to the use of a strong acidic substance with a pH of 1 or less, corrosion problems of cosmetic manufacturing equipment, resulting in heavy metal contamination of cosmetics, and difficulty in achieving consistent products during the cosmetic formulation process, thereby ensuring the safety of users' bodies and work required for cosmetic manufacturing. [Example]

[0061] The present invention will be described in more detail below with reference to examples.

[0062] These examples are provided to more specifically explain the present invention, and the scope of the present invention is not limited to these examples.

[0063] Example 1 According to the analytical method prescribed by the United States Pharmacopoeia, 1000 g (0.597 mol) of terephthalylidene dicamphorsulfonic acid (Ecamsule) aqueous solution with a purity of 33.6% was placed in a 2 L four-necked round-bottom flask, and 144.64 g (1.194 mol) of tromethamine with a molecular weight of 121.14 g / mol was added with stirring until completely dissolved, and the pH of the solution was adjusted to 6.6. The solution was filtered through filter paper to obtain a clear aqueous solution containing terephthalylidene dicamphorsulfonic acid·2-tromethamine, represented by the following chemical formula 1-1.

[0064] [ka]

[0065] <Example 2> 200 g of the aqueous solution of terephthalylidenedicamphorsulfonic acid·2-tromethamine obtained in Example 1 was slowly added dropwise over 30 minutes at room temperature to a beaker containing 800 ml of acetone, resulting in the precipitation of crystals. Stirring was continued for another 2 hours until the crystals were completely precipitated, and the crystals were filtered and washed to obtain the target product, terephthalylidenedicamphorsulfonic acid·2-tromethamine crystals. The crystals were dried in a vacuum to obtain 79.79 g of the target product (yield 95%).

[0066] Example 3 200 g of the terephthalylidene dicamphorsulfonic acid·2-tromethamine aqueous solution obtained in Example 1 was placed in a freeze dryer (Lyovapor™ L-300 model) and freeze-dried at ±1°C for 15 hours to obtain 83.98 g of terephthalylidene dicamphorsulfonic acid·2-tromethamine as a white powdery solid.

[0067] Example 4 According to the United States Pharmacopoeia analytical method, 1000 g (0.597 mol) of 33.6% pure terephthalylidene dicamphorsulfonic acid aqueous solution was placed in a 2 L four-neck round-bottom flask, and 178.13 g (1.194 mol) of triethanolamine with a molecular weight of 149.19 g / mol was added with stirring until completely dissolved, and the pH of the solution was adjusted to 6.6. The solution was filtered through filter paper to obtain a clear aqueous solution containing terephthalylidene dicamphorsulfonic acid·2-triethanolamine.

[0068] <Example 5> 200 g of the aqueous solution of terephthalylidene dicamphorsulfonic acid·2-triethanolamine obtained in Example 4 was slowly added dropwise over 30 minutes at room temperature to a beaker containing 800 ml of acetone, resulting in the precipitation of crystals. Stirring was continued for another 2 hours until the crystals were completely precipitated, and the mixture was then filtered and washed to obtain the target terephthalylidene dicamphorsulfonic acid·2-triethanolamine crystals. The terephthalylidene dicamphorsulfonic acid·2-triethanolamine crystals were vacuum dried to obtain 83.79 g of the target solid (yield 96%).

[0069] Example 6 200 g of the aqueous solution of terephthalylidene dicamphorsulfonic acid·2-triethanolamine obtained in Example 4 was placed in a freeze dryer (Lyovapor™ L-300 model) and freeze-dried at ±1°C for 15 hours to obtain 87.19 g of terephthalylidene dicamphorsulfonic acid·2-triethanolamine as a white powdery solid.

[0070] Example 7 According to the analytical method prescribed by the United States Pharmacopoeia, 1000 g (0.597 mol) of terephthalylidene dicamphorsulfonic acid aqueous solution with a purity of 33.6% was placed in a 2 L four-necked round-bottom flask, and 208 g (1.194 mol) of arginine with a molecular weight of 174.21 g / mol was added with stirring until completely dissolved, and the pH of the solution was adjusted to 6.6. The solution was filtered through filter paper to obtain a clear solution of terephthalylidene dicamphorsulfonic acid·2-arginine aqueous solution.

[0071] Example 8 200 g of the terephthalylidene dicamphorsulfonic acid·2-arginine aqueous solution obtained in Example 7 was slowly added dropwise over 30 minutes at room temperature to a beaker containing 800 ml of acetone, resulting in the precipitation of crystals. Stirring was continued for another 2 hours until the crystals were completely precipitated, followed by filtration and washing to obtain the target terephthalylidene dicamphorsulfonic acid·2-arginine crystals. The resulting crystals were vacuum dried to obtain 85.57 g of the target solid (yield 95%).

[0072] Example 9 200 g of the terephthalylidene dicamphorsulfonic acid·2-arginine aqueous solution obtained in Example 7 was placed in a freeze dryer (Lyovapor™ L-300 model) and freeze-dried at ±1°C for 15 hours to obtain 90.07 g of terephthalylidene dicamphorsulfonic acid·2-arginine as a white powdery solid.

[0073] Example 10 According to the United States Pharmacopoeia analytical method, 1000 g (0.597 mol) of terephthalylidene dicamphorsulfonic acid aqueous solution with a purity of 33.6% was placed in a 2 L four-neck round-bottom flask, and 106.43 g (1.194 mol) of 2-amino-2-methyl-1-propanol (AMP) with a molecular weight of 89.136 g / mol was added with stirring until completely dissolved, and the pH of the solution was adjusted to 6.6. The solution was filtered through filter paper to obtain a clear aqueous solution containing terephthalylidene dicamphorsulfonic acid 2AMP.

[0074] Example 11 200 g of the clear aqueous solution containing terephthalylidene dicamphorsulfonic acid·2AMP obtained in Example 10 was slowly added dropwise to a beaker containing 800 ml of acetone at room temperature over 30 minutes, resulting in the precipitation of crystals. Stirring was continued for another 2 hours until the crystals were completely precipitated, and the crystals were then filtered and washed to obtain the target terephthalylidene dicamphorsulfonic acid·2AMP crystals. These were then dried in a vacuum to obtain 75.97 g of the target powder solid (yield 95%).

[0075] <Comparative Example 1> According to the analytical method prescribed by the United States Pharmacopoeia, 1000 g (0.597 mol) of 33.6% pure terephthalylidene dicamphorsulfonic acid aqueous solution was placed in a 2 L four-neck round-bottom flask, and sodium hydroxide was added while stirring, resulting in the precipitation of a white solid. The terephthalylidene dicamphorsulfonic acid disodium salt obtained using inorganic NaOH as a neutralizer had a low solubility in water of 2-3% at room temperature, making it impossible to prepare a highly concentrated aqueous solution of 30% or more. Furthermore, its UV absorption effect was also reduced, making it unsuitable for use as a sunscreen.

[0076] <Experimental Example 1> Evaluation of the sustained stability of terephthalylidene dicamphorsulfonate Using the terephthalylidene dicamphorsulfonic acid·2-tromethamine aqueous solution of Example 1, an aqueous solution obtained by mixing the aqueous solution of Example 1 with 2.5% 1,2-hexanediol, and the terephthalylidene dicamphorsulfonic acid·2-tromethamine crystals of Example 2, a 33.6% aqueous solution of terephthalylidene dicamphorsulfonic acid (TDSA) was converted to the same equivalent weight. The stability was evaluated by analyzing the content by high-performance liquid chromatography (HPLC) every three months for 12 months and every six months for the next 24 months. The purity test was performed in accordance with the Ecamsule content test method of United States Pharmacopoeia 44. The stability test was performed in a dark, light-shielded, thermostatic chamber maintained at 45°C.

[0077] In the HPLC sample preparation method, in the case of a 33.6% aqueous solution of terephthalylidene dicamphorsulfonic acid, 300 mg of a 33.6% aqueous solution of terephthalylidene dicamphorsulfonic acid was placed in a 100 ml graduated flask, and the solution was adjusted to 100 ml with purified water. 5 ml of the above solution was then taken and placed again in a 100 ml graduated flask, and the solution was adjusted to 100 ml with purified water to prepare the sample.

[0078] In the case of the terephthalylidene dicamphorsulfonic acid·2-tromethamine aqueous solution of Example 1 and the aqueous solution of Example 1 mixed with 2.5% 1,2-hexanediol, samples were prepared in the same manner as above, and content tests were carried out.

[0079] 100 mg of the terephthalylidene dicamphorsulfonic acid 2-tromethamine crystals obtained in Example 2 was placed in a 100 ml measuring flask and diluted to 100 ml with purified water. 5 ml of the solution was then placed in a 100 ml measuring flask and diluted to 100 ml with purified water to prepare a sample. This solution was measured using an HPLC system manufactured by Shimadzu Corporation, and the results are shown in Table 1 below.

[0080] (Table 1) Stability evaluation results TIFF0007823968000004.tif48166

[0081] From the results in Table 1, it was confirmed that the aqueous solution of terephthalylidene dicamphorsulfonic acid is a strongly acidic solution, and that the purity decreases when stored at a high temperature of 45°C for a long period of time.

[0082] On the other hand, it was confirmed that the neutral salt aqueous solution of terephthalylidene dicamphorsulfonic acid·2-tromethamine in Example 1 is more stable than the acidic aqueous solution, and that the aqueous solution containing 1,2-hexanediol is even more stable. Furthermore, it was confirmed that the solid obtained by crystallizing the salt of terephthalylidene dicamphorsulfonic acid·2-tromethamine is stable not only at a high temperature of 45°C but also under long-term storage conditions of 24 months, with almost no decrease in content.

[0083] Although the present invention has been described in detail with reference to the specific examples described above, it will be apparent to those skilled in the art that various modifications and alterations are possible within the scope of the technical concept of the present invention, and it goes without saying that such modifications and alterations are intended to fall within the scope of the appended claims.

Claims

1. an organic salt of terephthalylidene dicamphorsulfonic acid useful for sunscreen cosmetics, obtained as a neutralized product by stoichiometrically bonding an organic amine compound to both ends of terephthalylidene dicamphorsulfonic acid in an equivalent ratio of 1:2; the organic amine compound is at least one selected from the group consisting of tromethamine, 2-amino-2-methyl-1-propanol (AMP), polyethyleneimine, spermidine, spermine, cadaverine, and putrescine; The organic salt is provided in an aqueous solution or powder form; An organic salt of terephthalylidene dicamphorsulfonic acid, characterized by ensuring long-term storage stability under high-temperature conditions of 45°C.

2. a step of stoichiometrically adding and dissolving one or more organic amine compounds selected from the group consisting of tromethamine, 2-amino-2-methyl-1-propanol (AMP), polyethyleneimine, spermidine, spermine, cadaverine, and putrescine in an equivalent ratio of 1:2 to the purified aqueous solution of terephthalylidene dicamphorsulfonic acid, adjusting the pH of the solution, and filtering the solution to obtain a clear aqueous solution; A method for producing an organic salt of terephthalylidene dicamphorsulfonic acid, which ensures long-term storage stability under a high-temperature condition of 45°C, comprising the step of adding one or more members selected from the group consisting of 1,2-alkanediol, ethylhexylglycerin, hydroxyacetophenone, and sodium benzoate to the clear aqueous solution.

3. The method for producing an organic salt of terephthalylidene dicamphorsulfonic acid according to claim 2, further comprising the steps of dropping the obtained clear aqueous solution into an organic solvent to precipitate crystals, and vacuum drying the crystals to obtain a powder.

4. 3. The method for preparing an organic salt of terephthalylidene dicamphorsulfonic acid according to claim 2, further comprising the step of freeze-drying the obtained clear aqueous solution to obtain a powder.

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