A stabilized hot spring sulfide active ingredient, and a preparation method and application thereof

Abstract

The application discloses a kind of stabilized hot spring sulfide active ingredients and its preparation method and application, belong to natural product processing and daily chemical technology field, including hot spring water or concentrated liquid rich in sulfide, sodium selenite, cationic polymer, hydrophobic silicone oil or natural oil, metal ion chelating agent, cyclodextrin inclusion zinc salt, natural aromatic oil and antioxidant.The application builds the dual stabilization and slow-release system of "electrostatic adsorption+physical barrier" by the in-situ synergistic effect of cationic polymer and oil, solves the contradiction between storage stability and service life.The final product of the application is extremely high in stability, has no bad smell, low irritability, and has smooth skin feel, completely overcomes the traditional obstacles of sulfur component in daily chemicals.

Description

Technical Field

[0001] This invention relates to the field of natural product processing and daily chemical products, specifically to a stabilized hot spring sulfide active ingredient, its preparation method, and its application. Background Technology

[0002] Sulfur hot springs (rich in hydrogen sulfide, thiosulfates, and other polysulfides) are renowned for their unique skin-soothing and health benefits. However, developing their active ingredients into stable products faces fundamental challenges:

[0003] 1. Chemical instability: The core active ingredient, hydrogen sulfide (H2S), is volatile and oxidized, and it is rapidly deactivated and produces an unpleasant odor during purification and storage.

[0004] 2. Formulation and sensory challenges: Free sulfides are sensitive to product pH and metal ions, which can easily lead to formula discoloration and precipitation, and their characteristic odor limits consumer acceptance.

[0005] 3. Risk of skin irritation: High concentrations or localized high concentrations of active sulfur may irritate sensitive skin.

[0006] 4. Limitations of existing technology: Current technology mainly relies on the direct addition of stable but low-activity sulfur sources such as sodium thiosulfate and colloidal sulfur, or the use of strong reducing / antioxidant agents to "seal" sulfides. The former cannot restore the core activity of hot springs, while the latter is inefficient and may affect the product system.

[0007] Therefore, developing a method that can simulate the continuous release principle of natural hot springs, significantly improve the stability of active sulfur, and enhance its application safety and sensory experience is key to realizing the high-value domestic application of sulfur hot springs. Summary of the Invention

[0008] In view of this, the present invention provides a method for efficiently converting unstable inorganic sulfides in hot spring water into stable, controllably released active sulfur components. This yields an active sulfur product with high stability, low irritation, and excellent skin feel. The product prepared by this invention can be used in the preparation of skin-soothing, cleansing bath products, and personal care products.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: A stabilized hot spring sulfide active ingredient includes sulfide-rich hot spring water or concentrate, sodium selenite, cationic polymer, hydrophobic silicone oil or natural oil, metal ion chelating agent, cyclodextrin-encapsulated zinc salt, natural aromatic oil and antioxidant. The molar ratio of selenium in the sodium selenite to sulfur in the sulfide-rich hot spring water or concentrate is 0.1-1:100. The cationic polymer is used at a rate of 0.5-3% of the mass of the sulfide-rich hot spring water or concentrate. The amount of the hydrophobic silicone oil or natural oil used is 1-5% of the mass of the sulfide-rich hot spring water or concentrate; The amount of the metal ion chelating agent used is 0.05-0.3% of the mass of the sulfide-rich hot spring water or concentrate; The amount of zinc salt encapsulated in the cyclodextrin is 0.05-0.15% of the mass of the sulfide-rich hot spring water or concentrate; The amount of the natural aromatic oil used is 0.05-0.15% of the mass of the sulfide-rich hot spring water or concentrate; The amount of antioxidant used is 0.5-2% of the mass of the sulfide-rich hot spring water or concentrate.

[0010] The product of this invention is a homogeneous emulsion or dispersion with a particle size distribution between 100-500 nm. After 90 days of accelerated stability testing at 40°C, the retention rate of effective active sulfur (calculated as polysulfides and thiosulfates) is ≥85%, with no obvious sulfur odor precipitated. In a simulated bath environment (40°C deionized water), the active sulfur in the product exhibits a gradual release curve within 30 minutes, without explosive release, thus reducing instantaneous irritation. A patch test with a 3% dilution of the product on humans showed a 0% irritation rate, making it suitable for sensitive skin.

[0011] Furthermore, the cationic polymer is polyquaternium-51 or a chitosan derivative; the hydrophobic silicone oil is cyclopentadimethylsiloxane.

[0012] Furthermore, the metal ion chelating agent is disodium ethylenediaminetetraacetate; the zinc salt encapsulated by the cyclodextrin is zinc gluconate.

[0013] Furthermore, the natural aromatic oil is tea tree oil and / or cedarwood oil; the antioxidant is vitamin C and its derivatives.

[0014] The vitamin C derivative is 3-O-ethyl ascorbic acid (EAC), ascorbate palmitate, or ascorbate tetraisopalmitate.

[0015] In the above scheme, zinc ions can synergistically enhance the effect with trace amounts of free sulfur, while cyclodextrin encapsulation and the addition of aromatic oils can effectively mask residual sulfur odor and improve the sensory experience.

[0016] This invention also provides a method for preparing the above-mentioned stabilized hot spring sulfide active components, comprising the following steps: (1) Mild catalytic oxidation and sulfur form conversion: Adjust the pH of hot spring water or concentrated solution rich in sulfides to 7.5-9.0, heat and stir at low temperature and introduce oxygen-containing flow, then add sodium selenite as a catalyst to react and obtain reaction solution; (2) Construction of in-situ polymerization encapsulation and sustained release system: Cationic polymer is added to the reaction solution, and then hydrophobic silicone oil or natural oil is added under high-speed shearing to form a “Pickering type” microemulsion or submicron particle dispersion with active sulfur-polymer complex as water core and oil as partial encapsulation layer in situ; (3) Terminal chelation and sensory modification: Add metal ion chelating agent to the system obtained in step (2), then add zinc salt encapsulated by cyclodextrin, natural aromatic oil and antioxidant, and stir evenly to obtain stable hot spring sulfide active ingredients.

[0017] Furthermore, the temperature of the low-temperature heating and stirring in step (1) is 20-40℃, the stirring rate is 200-400rpm, and the reaction time is 30-90min.

[0018] Furthermore, the oxygen content of the oxygen-containing flow is 20 vol% or more.

[0019] In step (1), the present invention will partially destabilize S² - HS - It is transformed into a series of intermediate polysulfides (S) with higher stability and bioavailability. x ² - (x=2-6) and thiosulfate (S2O3²) - The endpoint of the process is determined by monitoring the redox potential (ORP) to ensure it stabilizes at a specific plateau.

[0020] Furthermore, the high-speed shearing rotation in step (2) is 5000-15000 rpm, and the processing time is 10-20 min.

[0021] In step (2), the present invention utilizes the electrostatic interaction and shear force between cationic polymers and negatively charged polysulfide ions to form in situ a “Pickering type” microemulsion or submicron particle dispersion with an active sulfur-polymer complex as the water core and oil as a partial coating layer.

[0022] This invention also provides the application of stabilized hot spring sulfide active ingredients in the preparation of daily necessities.

[0023] The daily necessities mentioned are sulfur hot spring bath essence, bath salt balls, shower gel, or local skin soothing care products, or scalp cleansing and care products. The local skin soothing care products include face masks, serums, and body lotions.

[0024] The beneficial effects of this invention are as follows: 1. Achieved active conversion: This invention transforms unstable hydrogen sulfide into a polysulfide spectrum that combines activity and stability through mild catalytic oxidation, thus preserving the core functional material basis of hot spring sulfur.

[0025] 2. A unique stabilization structure is created: This invention constructs a dual stabilization and slow-release system of "electrostatic adsorption + physical barrier" through the in-situ synergistic effect of cationic polymers and oils, which solves the contradiction between storage stability and usage timeliness.

[0026] 3. Significantly improved product quality: The final product of this invention has extremely high stability, no unpleasant odor, low irritation, and a smooth skin feel, completely overcoming the traditional obstacles to the application of sulfur components in daily chemical products.

[0027] 4. The process is universal and efficient: The method of this invention is mild and suitable for treating sulfur-containing hot spring water of different concentrations. It is easy to scale up production and provides a reliable core raw material solution for developing high-end sulfur hot spring-derived care products. Detailed Implementation

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1 (1) Take 100L of pre-filtered Tengchong sulfur hot spring water (its total sulfur content was tested and expressed as S²). - The concentration of sodium selenite was 50 mg / L, and the pH was adjusted to 8.5. Sodium selenite was added at 30°C (to bring the Se concentration to 0.1 mg / L), air was introduced at a flow rate of 0.5 L / min and the mixture was continuously stirred, and the reaction was carried out for 60 min until the ORP value stabilized.

[0030] (2) Add 0.5% of polyquaternium-51 to the reaction solution, and add 2% of cyclopentadimethylsiloxane under high-speed shearing at 8000 rpm. Continue shearing for 15 min to obtain a milky white microemulsion dispersion.

[0031] (3) Add 0.1% disodium EDTA, 0.15% zinc gluconate encapsulated with β-cyclodextrin, 0.08% tea tree oil and 0.5% vitamin C, and homogenize to obtain about 95L of active sulfur concentrated slurry.

[0032] The product prepared in Example 1 was tested: the average particle size was 220 nm as determined by dynamic light scattering instrument; the effective sulfur retention rate was 91% after accelerated testing; and the cumulative release rate was 68% in the in vitro Franz diffusion cell simulated release test after 30 min, with a smooth release curve.

[0033] Example 2 (1) Take 100L of pre-filtered Tengchong sulfur hot spring water (its total sulfur content was tested and expressed as S²). - The concentration was 49 mg / L, and the pH was adjusted to 7.5. Sodium selenite was added at 20°C (to bring the Se concentration to 0.4 mg / L), air was introduced at a flow rate of 0.5 L / min and the mixture was continuously stirred, and the reaction was carried out for 30 min until the ORP value stabilized.

[0034] (2) Add 0.2% of polyquaternium-51 to the reaction solution, and add 5% of cyclopentadimethylsiloxane under high-speed shearing at 5000 rpm. Continue shearing for 20 min to obtain a milky white microemulsion dispersion.

[0035] (3) Add 0.05% disodium EDTA, 0.1% zinc gluconate encapsulated with β-cyclodextrin, 0.15% tea tree oil and 2.0% ascorbate palmitate, and homogenize to obtain approximately 96.2L of active sulfur concentrate slurry.

[0036] The product prepared in Example 2 was tested: the average particle size was 215 nm as determined by dynamic light scattering instrument; the effective sulfur retention rate was 90% after accelerated testing; and the cumulative release rate was 67% in the in vitro Franz diffusion cell simulated release test after 30 min, with a smooth release curve.

[0037] Example 3 (1) Take 100L of pre-filtered Tengchong sulfur hot spring water (its total sulfur content was tested and expressed as S²). - The concentration of selenite was 51 mg / L, and the pH was adjusted to 8. Sodium selenite was added at 40°C (to make the Se concentration reach 0.05 mg / L), air was introduced at a flow rate of 0.5 L / min and the mixture was continuously stirred, and the reaction was carried out for 90 min until the ORP value stabilized.

[0038] (2) Add 2.5% of polyquaternium-51 to the reaction solution, and add 3% of cyclopentadimethylsiloxane under high-speed shearing at 13000 rpm. Continue shearing for 10 min to obtain a milky white microemulsion dispersion.

[0039] (3) Add 0.3% disodium EDTA, 0.05% zinc gluconate encapsulated with β-cyclodextrin, 0.12% cedar oil and 1.5% 3-O-ethyl ascorbic acid, and homogenize to obtain approximately 94.5L of active sulfur concentrated slurry.

[0040] The product prepared in Example 3 was tested: the average particle size was 217 nm as determined by dynamic light scattering instrument; the effective sulfur retention rate was 92% after accelerated testing; and the cumulative release rate was 68% in the in vitro Franz diffusion cell simulated release test after 30 min, with a smooth release curve.

[0041] Example 4 (1) Take 100L of pre-filtered Tengchong sulfur hot spring water (its total sulfur content was tested and expressed as S²). - The concentration was 51 mg / L. The pH was adjusted to 7.8. Sodium selenite was added at 25°C (to make the Se concentration 0.2 mg / L), air was introduced at a flow rate of 0.5 L / min and the mixture was stirred continuously. The reaction was allowed to proceed for 25 min until the ORP value stabilized.

[0042] (2) Add 1.2% of polyquaternium-51 to the reaction solution, and add 3.5% of cyclopentadimethylsiloxane under high-speed shearing at 8000 rpm. Continue shearing for 10 min to obtain a milky white microemulsion dispersion.

[0043] (3) Add 0.15% disodium EDTA, 0.07% zinc gluconate encapsulated with β-cyclodextrin, 0.13% cedar oil and 1.5% 3-O-ethyl ascorbic acid, and homogenize to obtain approximately 95.3L of active sulfur concentrate slurry.

[0044] The product prepared in Example 4 was tested: the average particle size was 225 nm as determined by dynamic light scattering instrument; the effective sulfur retention rate after accelerated testing was 90.5%; and the cumulative release rate in the in vitro Franz diffusion cell simulated release test was 69% after 30 min, with a smooth release curve.

[0045] Example 5 (1) Take 100L of pre-filtered Tengchong sulfur hot spring water (its total sulfur content was tested and expressed as S²). - The concentration of the solution was 51 mg / L, and the pH was adjusted to 8.2. Sodium selenite was added at 35°C (to bring the Se concentration to 0.2 mg / L), and air was introduced at a flow rate of 0.5 L / min with continuous stirring. The reaction was carried out for 60 min until the ORP value stabilized.

[0046] (2) Add 2.3% of polyquaternium-51 to the reaction solution, and add 2.5% of cyclopentadimethylsiloxane under high-speed shearing at 6000 rpm. Continue shearing for 10 min to obtain a milky white microemulsion dispersion.

[0047] (3) Add 0.2% disodium EDTA, 0.1% zinc gluconate encapsulated with β-cyclodextrin, 0.15% cedar oil and 1.6% 3-O-ethyl ascorbic acid, and homogenize to obtain approximately 96.6 L of active sulfur concentrated slurry.

[0048] The product prepared in Example 5 was tested: the average particle size was 215 nm as determined by dynamic light scattering instrument; the effective sulfur retention rate after accelerated testing was 91.5%; and the cumulative release rate in the in vitro Franz diffusion cell simulated release test was 68.5% over 30 minutes, with a smooth release curve.

[0049] Example 6 (1) Take 100L of pre-filtered Tengchong sulfur hot spring water (its total sulfur content was tested and expressed as S²). - The concentration was 51 mg / L. The pH was adjusted to 7.5. Sodium selenite was added at 20°C (to make the Se concentration reach 0.3 mg / L), air was introduced at a flow rate of 0.5 L / min and the mixture was stirred continuously. The reaction was allowed to proceed for 80 min until the ORP value stabilized.

[0050] (2) Add 3% of polyquaternium-51 to the reaction solution, and add 4.5% of cyclopentadimethylsiloxane under high-speed shearing at 13000 rpm. Continue shearing for 10 min to obtain a milky white microemulsion dispersion.

[0051] (3) Add 0.18% disodium EDTA, 0.1% zinc gluconate encapsulated with β-cyclodextrin, 0.1% cedar oil and 0.8% 3-O-ethyl ascorbic acid, and homogenize to obtain approximately 95.7L of active sulfur concentrate slurry.

[0052] The product prepared in Example 6 was tested: the average particle size was 210 nm as determined by dynamic light scattering instrument; the effective sulfur retention rate was 93% after accelerated testing; and the cumulative release rate was 70% in the in vitro Franz diffusion cell simulated release test after 30 min, with a smooth release curve.

[0053] Example 7 (1) Take 100L of pre-filtered Tengchong sulfur hot spring water (its total sulfur content was tested and expressed as S²). - The concentration was 51 mg / L, and the pH was adjusted to 8.3. Sodium selenite was added at 30°C (to make the Se concentration reach 0.35 mg / L), air was introduced at a flow rate of 0.5 L / min and the mixture was stirred continuously for 75 min until the ORP value stabilized.

[0054] (2) Add 1.8% of polyquaternium-51 to the reaction solution, and add 2.6% of cyclopentadimethylsiloxane under high-speed shearing at 13000 rpm. Continue shearing for 10 min to obtain a milky white microemulsion dispersion.

[0055] (3) Add 0.23% disodium EDTA, 0.07% zinc gluconate encapsulated with β-cyclodextrin, 0.13% cedar oil and 1.8% 3-O-ethyl ascorbic acid, and homogenize to obtain approximately 94.2 L of active sulfur concentrate slurry.

[0056] The product prepared in Example 7 was tested: the average particle size was 220 nm as determined by dynamic light scattering instrument; the effective sulfur retention rate after accelerated testing was 91.5%; and the cumulative release rate in the in vitro Franz diffusion cell simulated release test was 67.5% over 30 minutes, with a smooth release curve.

[0057] Comparative example: Traditional direct stabilization method 100L of the same batch of hot spring water as in Example 1 was taken, and 0.5% sodium thiosulfate and 0.5% sodium bisulfite were added directly as stabilizers and mixed thoroughly. The resulting solution became turbid and developed a distinct sulfur odor after being stored at 40°C for 30 days, with an effective sulfur retention rate of only 42%. Furthermore, reports indicated a slight skin irritation after dilution.

[0058] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A stabilized active ingredient of hot spring sulfides, characterized in that, Including sulfide-rich hot spring water or concentrate, sodium selenite, cationic polymers, hydrophobic silicone oils or natural oils, metal ion chelating agents, zinc salts encapsulated in cyclodextrin, natural aromatic oils, and antioxidants. The molar ratio of selenium in the sodium selenite to sulfur in the sulfide-rich hot spring water or concentrate is 0.1-1:

100. The cationic polymer is used at a rate of 0.5-3% of the mass of the sulfide-rich hot spring water or concentrate. The amount of the hydrophobic silicone oil or natural oil used is 1-5% of the mass of the sulfide-rich hot spring water or concentrate; The amount of the metal ion chelating agent used is 0.05-0.3% of the mass of the sulfide-rich hot spring water or concentrate; The amount of zinc salt encapsulated in the cyclodextrin is 0.05-0.15% of the mass of the sulfide-rich hot spring water or concentrate; The amount of the natural aromatic oil used is 0.05-0.15% of the mass of the sulfide-rich hot spring water or concentrate; The amount of antioxidant used is 0.5-2% of the mass of the sulfide-rich hot spring water or concentrate.

2. The stabilized hot spring sulfide active ingredient according to claim 1, characterized in that, The cationic polymer is polyquaternium-51 or a chitosan derivative; the hydrophobic silicone oil is cyclopentadimethylsiloxane.

3. The stabilized hot spring sulfide active ingredient according to claim 1, characterized in that, The metal ion chelating agent is disodium ethylenediaminetetraacetate; the zinc salt encapsulated by the cyclodextrin is zinc gluconate.

4. The stabilized hot spring sulfide active ingredient according to claim 1, characterized in that, The natural aromatic oil is tea tree oil and / or cedarwood oil; the antioxidant is vitamin C and its derivatives.

5. A method for preparing the stabilized active ingredient of hot spring sulfides according to any one of claims 1-4, characterized in that, Includes the following steps: (1) Mild catalytic oxidation and sulfur form conversion: Adjust the pH of hot spring water or concentrated solution rich in sulfides to 7.5-9.0, heat and stir at low temperature and introduce oxygen-containing flow, then add sodium selenite as a catalyst to react and obtain reaction solution; (2) Construction of in-situ polymerization encapsulation and sustained release system: Cationic polymer is added to the reaction solution, and then hydrophobic silicone oil or natural oil is added under high-speed shearing to form a "Pickering type" microemulsion or submicron particle dispersion with active sulfur-polymer complex as water core and oil as partial encapsulation layer in situ; (3) Terminal chelation and sensory modification: Add metal ion chelating agent to the system obtained in step (2), then add zinc salt encapsulated by cyclodextrin, natural aromatic oil and antioxidant, and stir evenly to obtain stable hot spring sulfide active ingredients.

6. The method for preparing a stabilized active ingredient of hot spring sulfide according to claim 5, characterized in that, The temperature for low-temperature heating and stirring in step (1) is 20-40℃, the stirring rate is 200-400rpm, and the reaction time is 30-90min.

7. The method for preparing a stabilized active ingredient of hot spring sulfide according to claim 5 or 6, characterized in that, The oxygen content of the oxygen-containing flow is above 20 vol%.

8. The method for preparing a stabilized active ingredient of hot spring sulfide according to claim 5, characterized in that, The high-speed shearing rotation in step (2) is 5000-15000 rpm, and the processing time is 10-20 min.

9. The use of the stabilized hot spring sulfide active ingredient as described in any one of claims 1-4 in the preparation of daily necessities.