Maltodextrin-based temperature response microcapsule as well as preparation method and application thereof

Abstract

The invention relates to a maltodextrin-based temperature response microcapsule as well as a preparation method and application thereof. A core material of the microcapsule is natural essential oil, and a wall material of the microcapsule is a maltodextrin-based temperature-sensitive material; the microcapsule takes deionized water as a solvent and comprises the following raw material components: 1-5wt% of natural essential oil; 2 to 10 wt% of a maltodextrin-based temperature-sensitive material; and 1-5 wt% of a surfactant. Compared with the prior art, the preparation method has the advantages that the maltodextrin and the temperature-sensitive material are combined by using binary (or higher) acid anhydride to form the composite wall material, so that the high-stability microcapsule which is intelligently regulated and controlled by the temperature to release the essential oil is obtained. The method can improve the stability of the core material, realizes intelligent controlled release of the core material, and can be applied to the fields of skin care, food preservation, household cleaning and the like.

Description

Technical Field

[0001] The invention relates to the technical field of microcapsules, and in particular to a maltodextrin-based temperature-responsive microcapsule and a preparation method and application thereof. Background Art

[0002] Natural essential oils have multiple functions such as soothing, whitening, antibacterial, anti-inflammatory, and deodorizing, so they are widely used in skin care, aromatherapy, household cleaning, food preservation and other fields. With the development of social production and consumption levels and green chemistry, consumers' demand for natural essential oils will further increase. However, natural essential oils contain a large amount of terpene compounds, which are less stable and easily oxidized and deteriorated, which affects the practical application of essential oils.

[0003] Using microcapsule wall materials to encapsulate essential oils can reduce the contact between essential oils and the outside world and greatly improve the stability of essential oils. Maltodextrin is obtained by hydrolysis of starch. It is safe, has good water solubility and film-forming properties, stable physical and chemical properties, and low cost. It is very suitable for use as microcapsule wall materials. Thermosensitive materials such as gelatin undergo phase changes due to temperature changes. When the temperature is lower than the upper critical solution temperature (UCST) of the material, the material changes from liquid to solid. When the temperature is higher than the UCST of the material, the material changes from solid to liquid.

[0004] Chinese patent CN103949196A discloses a osmanthus essence microcapsule powder and its preparation method and application. The osmanthus essence microcapsule is a heat-resistant sustained-release type, and its components are calculated by weight percentage: 5-25% oil-soluble osmanthus essence; 30-47% modified gum arabic A-2010; 43-51% maltodextrin. The method is simple and controllable, with good repeatability. The aroma retention rate at high temperature reaches 85%, and the aroma retention rate in three months reaches 90%. It has high heat resistance and good sustained-release properties, but the osmanthus essence microcapsule cannot cope with changes in ambient temperature and can only passively release essential oils. Secondly, Chinese patent CN101104596A discloses a trimethylol long-chain alkane-diisocyanate adduct and its preparation method, and provides a temperature-responsive self-enclosed aromatic sustained-release microcapsule using the adduct as a raw material and its preparation method. However, the diisocyanate material used is highly toxic and has a greater impact on environmental pollution. Summary of the invention

[0005] The purpose of the present invention is to provide a maltodextrin-based temperature-responsive microcapsule and a preparation method and application thereof, which can realize the controlled release of essential oils in response to changes in ambient temperature and the materials used are low in toxicity or non-toxic and are green and environmentally friendly.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] In one aspect, the present invention provides a maltodextrin-based temperature-responsive microcapsule, wherein the core material of the microcapsule is natural essential oil, and the wall material of the microcapsule is maltodextrin-based temperature-sensitive material.

[0008] Preferably, the microcapsules use deionized water as solvent, and the raw materials thereof include: 1-5wt% natural essential oil, 2-10wt% maltodextrin-based temperature-sensitive material, and 1-5wt% surfactant.

[0009] Further preferably, the mass percentage of the natural essential oil being 1-5 wt % means that the mass ratio of the natural essential oil to deionized water is (1-5):100.

[0010] Further preferably, the mass percentage of the maltodextrin-based thermosensitive material is 2-10 wt %, which means that the mass ratio of the maltodextrin-based thermosensitive material to deionized water is (2-10):100.

[0011] More preferably, the mass percentage of the surfactant is 1-5 wt %, which means that the mass ratio of the surfactant to deionized water is (1-5):100.

[0012] Preferably, the natural essential oil is selected from one or more of lavender essential oil, rosemary essential oil, lemon essential oil, and jasmine essential oil, and the surfactant is selected from one or more of sodium lauryl sulfate, Tween 80, Tween 20, Span 80, and sodium carboxymethyl cellulose.

[0013] Preferably, the maltodextrin-based thermosensitive material uses deionized water as solvent, and its raw materials include 5-30wt% maltodextrin, 5-10wt% acid anhydride, 20-50wt% thermosensitive material, 0.1-2wt% hydrochloric acid, and 0.1-2wt% sodium hydroxide.

[0014] Further preferably, the mass percentage of maltodextrin being 5-30wt% means that the mass ratio of maltodextrin to deionized water is (5-30):100.

[0015] More preferably, the mass percentage of the acid anhydride being 5-10 wt % means that the mass ratio of the acid anhydride to deionized water is (5-10):100.

[0016] Further preferably, the mass percentage of the temperature-sensitive material is 20-50wt%, which means that the mass ratio of the temperature-sensitive material to deionized water is (20-50):100.

[0017] Further preferably, the mass percentage of the hydrochloric acid of 0.1-2 wt % means that the mass ratio of hydrochloric acid to deionized water is (0.1-2):100.

[0018] Further preferably, the mass percentage of sodium hydroxide of 0.1-2 wt % means that the mass ratio of sodium hydroxide to deionized water is (0.1-2):100.

[0019] Further preferably, the acid anhydride is a dibasic or higher acid anhydride, and the acid anhydride is selected from one or more of succinic anhydride, glutaric anhydride, adipic anhydride, citric anhydride, polyisobutylene succinic anhydride, and trimellitic anhydride; the temperature-sensitive material is selected from one or more of gelatin, elastin polypeptide, chitosan, hydroxybutyl chitosan, methyl cellulose, and hydroxypropyl methyl cellulose.

[0020] In a second aspect, the present invention also provides a method for preparing the above-mentioned maltodextrin-based temperature-responsive microcapsules, comprising the following steps: dissolving the maltodextrin-based temperature-sensitive material in deionized water and stirring to dissolve, adding natural essential oil and surfactant according to mass percentage and mixing and stirring, obtaining a maltodextrin-based temperature-responsive microcapsule solution after homogenization, and freeze-drying the microcapsule solution to obtain a maltodextrin-based temperature-responsive microcapsule powder.

[0021] Preferably, the stirring and dissolving time of the maltodextrin-based temperature-sensitive material is 60 to 120 minutes, and the stirring speed is 400 to 600 rpm.

[0022] Preferably, after adding the natural essential oil and the surfactant, stirring is first performed at a stirring speed of 400 to 600 rpm for 20 to 30 minutes, and then homogenized for 3 to 8 minutes.

[0023] Preferably, the freeze-drying temperature is -50 to -60°C, and the freeze-drying time is 40 to 56 hours.

[0024] Further preferably, the homogenization rate is 10000-22000 rpm.

[0025] Preferably, the maltodextrin-based thermosensitive material is prepared by the following method: maltodextrin and thermosensitive material are dissolved in deionized water to obtain maltodextrin solution and thermosensitive material solution respectively; after adjusting the pH of the maltodextrin solution to 6.0-9.0 by adding sodium hydroxide, anhydride is added for reaction, and then the thermosensitive material solution is added for reaction, and during the whole reaction process, sodium hydroxide is added dropwise at the same time so that the pH of the solution is always maintained at 6.0-9.0 during the whole reaction process. After the reaction is completed, the pH is adjusted to 4.5-7.0 by adding hydrochloric acid, the product is poured into anhydrous ethanol, precipitated, filtered, washed with anhydrous ethanol, and dried to obtain the maltodextrin-based thermosensitive material.

[0026] Further preferably, the concentration of the maltodextrin solution is 0.05-0.3 g / ml, and the maltodextrin solution is prepared by dissolving the maltodextrin in water at a dissolving temperature of 50-70° C. and a stirring speed of 400-600 rpm for 90-120 min.

[0027] More preferably, the DE value of the maltodextrin is 5-18.

[0028] Further preferably, the concentration of the thermosensitive material solution is 0.2-0.5 g / ml, and the thermosensitive material solution is prepared by dissolving the thermosensitive material in water at a dissolving temperature of 10-40° C. and a stirring speed of 400-600 rpm for 90-120 min.

[0029] Further preferably, the reaction time after adding the acid anhydride is 180 to 300 minutes, and the reaction time after adding the temperature-sensitive material solution and adjusting the pH of the solution is 180 to 300 minutes.

[0030] More preferably, the acid anhydride should be slowly added to the pH-adjusted maltodextrin solution, and the acid anhydride is added at a rate of 0.04 to 0.08 g / min.

[0031] In a third aspect, the present invention further provides an application of the above-mentioned maltodextrin-based temperature-responsive microcapsules in the preparation of skin care cosmetics, the preparation of cotton fabric finishing agents, and the preparation of food preservative materials.

[0032] The present invention provides a maltodextrin-based temperature-responsive microcapsule, wherein the preparation of the maltodextrin-based temperature-sensitive material as a raw material and the mechanism of its controlled release of essential oil are as follows:

[0033] Maltodextrin is a soluble polysaccharide obtained by partial hydrolysis of starch. Its main component is an oligosaccharide composed of glucose units connected by α-1,4-glycosidic bonds, which contains a large number of hydroxyl groups. The binary (or higher) anhydride molecules contain multiple anhydride groups, which can make the hydroxyl groups in the maltodextrin molecules more reactive. Under weak alkaline conditions, the hydroxyl groups of maltodextrin are deprotonated and react with the anhydride groups to form ester bonds. Subsequently, the other (remaining) anhydride groups in the binary (or higher) anhydride molecules can react with the hydroxyl, carboxyl or amino groups of the temperature-sensitive material to form esters or amides, thereby ultimately achieving simultaneous grafting of maltodextrin with the temperature-sensitive material, and improving the mechanical strength, hygroscopicity and dispersibility of the composite wall material of maltodextrin and the temperature-sensitive material. The prepared maltodextrin-based temperature-responsive microcapsules are used to encapsulate core materials such as natural essential oils. In a low temperature environment, when the temperature is lower than the UCST of the thermosensitive wall material of the microcapsule, the activity of water molecules is weak, which enhances the hydrogen bonding between the thermosensitive wall material molecules and promotes the arrangement and cross-linking of the molecular chains, thereby forming a gel solid structure, making it difficult to release the essential oil. As the temperature rises, on the one hand, the mobility of water molecules increases, the interaction between the hydrophilic groups of the thermosensitive wall material and water increases, and the distance between the molecular chains of the thermosensitive wall material increases, which increases the mobility of the molecular chains, thereby promoting the dissolution of the wall material and releasing the essential oil. This method can be applied to skin care, food preservation, household cleaning and other fields because it can improve the stability of the core material and realize intelligent controlled release of the core material.

[0034] Compared with traditional microcapsules, the microcapsules prepared by the present invention can realize the controlled release of essential oils in response to changes in ambient temperature. At 4°C, the temperature-sensitive material condenses to form a gel solid structure, which prevents the release of essential oils. As the temperature rises to 32°C, the temperature-sensitive material interacts more with water molecules and dissolves, prompting the release of essential oils. In addition, the materials involved in the present invention have low or no toxicity, are environmentally friendly, and are in line with the trend of green development.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] (1) The maltodextrin-based temperature-responsive microcapsules provided by the present invention combine maltodextrin with a temperature-sensitive material by using a dibasic (or higher) acid anhydride to form a composite wall material, which can isolate the core material from the outside world, improve the stability of the core material, and realize intelligent controlled release of the core material through temperature changes.

[0037] (2) The temperature response characteristics of the maltodextrin-based temperature-responsive microcapsules provided by the present invention can be adjusted by adjusting the ratio of maltodextrin to the temperature-sensitive material.

[0038] (3) The maltodextrin-based temperature-responsive microcapsules provided by the present invention have uniformly dispersed sizes and exhibit excellent stability in a low-temperature environment.

[0039] (4) The maltodextrin-based temperature-responsive microcapsules provided by the present invention have a simple preparation process and can be widely used in many fields.

[0040] (5) The materials involved in the present invention are low in toxicity or non-toxic and biodegradable, which is in line with the trend of green development. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a morphological characteristic diagram of the maltodextrin-based temperature-responsive microcapsule of Example 1 of the present invention under a scanning electron microscope;

[0042] Figure 2 This is a macroscopic schematic diagram of the maltodextrin-based temperature-responsive microcapsule of Example 2 of the present invention at different temperatures;

[0043] Figure 3 This is a schematic diagram of the cumulative release amount of essential oil in the essential oil microcapsules at different ratios of maltodextrin to gelatin as the temperature changes in Example 3 of the present invention;

[0044] Figure 4 This is a schematic diagram of the cumulative release of essential oil in microcapsules on the mask cloth over time at different temperatures in Example 4 of the present invention. DETAILED DESCRIPTION

[0045] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0046] Unless otherwise specified, the reagents, methods, instruments and equipment used in the present invention are conventional reagents, methods, instruments and equipment in the art. Unless otherwise specified, the reagents and materials used in the following examples are commercially available, wherein the DE value of the maltodextrin used in the following examples is 15.

[0047] The present invention is further described below in conjunction with specific embodiments.

[0048] Example 1

[0049] 4g and 10g of maltodextrin and hydroxybutyl chitosan were dissolved in 10g of water at 60℃ and 25℃, respectively, and stirred at 400rpm for 1.5h. Turn off the water bath heating, let the solution temperature drop to room temperature, adjust the pH of the maltodextrin solution to 8.5, slowly add 2g of citric anhydride, react for 4h, add the previously dissolved hydroxybutyl chitosan solution to the solution, and continue to react for 4h. During the entire reaction process, sodium hydroxide was continuously added to maintain the pH at 8.5. After the reaction, the pH was adjusted to 5.5, the product was poured into anhydrous ethanol, precipitated, filtered, washed with anhydrous ethanol, and dried for use. Take 1g of maltodextrin-based thermosensitive material and dissolve it in 20g of deionized water, stir at 400rpm for 60min, add 0.24g of lavender essential oil to the solution, stir for 30min, add 0.2g of Span 80, stir at 400rpm for 30min, and homogenize the mixed solution for 5min. After freeze drying for 48 hours, the flavor microcapsule powder was obtained. Figure 1 This is a scanning electron microscope morphology characteristic diagram of the maltodextrin-based temperature-responsive microcapsules of this embodiment. It can be seen from the figure that the particle size of the microcapsules is uniform, and the average particle size is 2.656 μm.

[0050] Example 2

[0051] Dissolve 2g and 8g of maltodextrin and gelatin in 10g of water at 60℃ and 40℃, respectively, and stir at 600rpm for 2h. Turn off the water bath heating, let the solution temperature drop to room temperature, adjust the pH of the maltodextrin solution to 8, slowly add 2g of succinic anhydride, and react for 3h. Add the previously dissolved gelatin to the solution and continue to react for 3h. During the entire reaction process, sodium hydroxide is continuously added to maintain the pH at 8. After the reaction is completed, adjust the pH to 6, pour the product into anhydrous ethanol, precipitate, filter, wash with anhydrous ethanol, and dry for use. Take 2g of maltodextrin-based thermosensitive material and dissolve it in 20g of deionized water, stir at 600rpm for 90min to dissolve, add 0.24g of lavender essential oil to the solution, stir for 30min, add 0.2g of Tween 80, stir at 600rpm for 30min, homogenize the mixed solution for 8min, and obtain an essential oil microcapsule emulsion. Figure 2 Schematic diagram of the macroscopic microcapsules at different temperatures of this embodiment. It can be seen from the figure that at low temperature and 4°C, the prepared microcapsules have excellent stability and the essential oil is encapsulated in the microcapsules; at high temperature, i.e., 32°C, the essential oil is released.

[0052] Example 3

[0053] Weigh 5 groups of samples, the total mass of maltodextrin and gelatin in each group of samples is 9 grams, and the mass ratio of maltodextrin to gelatin is 2:1, 1:1, 1:2, 1:3 and 1:4 respectively. Dissolve the maltodextrin and gelatin in 10g water at 60℃ and 40℃ respectively and stir at 600rpm for 2h. Turn off the water bath heating to lower the solution temperature to room temperature, adjust the pH of the maltodextrin solution to 9, slowly add 2g of trimellitic anhydride and react for 5h. Add the previously dissolved gelatin solution to the solution and continue to react for 5h. During the entire reaction process, sodium hydroxide is continuously added to maintain the pH at 9. After the reaction is completed, the pH is adjusted to 7, the product is poured into anhydrous ethanol, precipitated, filtered, washed with anhydrous ethanol, and dried for use. 1 g of maltodextrin-based thermosensitive material was dissolved in 25 g of deionized water and stirred at 400 rpm for 120 min. 1.25 g of lavender essential oil was added to the solution and stirred for 30 min. 0.25 g of Tween 20 was added and stirred at 400 rpm for 30 min. The mixed solution was homogenized for 3 min to obtain an essential oil microcapsule solution.

[0054] The temperature response characteristics of the five groups of microcapsules prepared above were investigated. Cyclohexane was used as the solvent to prepare a series of gradient concentrations of 0.05 mg / ml, 0.1 mg / ml, 0.2 mg / ml, 0.25 mg / ml and 0.3 mg / ml of lavender oil, and a full spectrum scan of 1 mg / ml lavender essential oil was performed using an ultraviolet spectrophotometer to obtain a maximum absorption wavelength of 220 nm for lavender essential oil. The absorbance of the gradient concentration of lavender oil was measured at a fixed wavelength to draw a UV standard curve for lavender essential oil. Weigh 5 groups of essential oil microcapsule emulsions, 5 g each, and place them at 4 ° C, 12 ° C, 24 ° C, 32 ° C, and 40 ° C for 25 min. Take 0.25 g of the solution and mix it with 10 ml of cyclohexane, ultrasonicate for 3 min, centrifuge at 10000 rpm for 20 min, absorb the upper liquid, dilute it 20 times, and use an ultraviolet spectrophotometer to test its absorbance to obtain the release rate of the essential oil. Figure 3 The results show that the temperature response characteristics of the prepared essential oil microcapsules are optimal when the ratio of maltodextrin to gelatin is 1:3.

[0055] Example 4

[0056] Dissolve 2g and 6g of maltodextrin and gelatin in 10g of water at 60℃ and 40℃, respectively, and stir at 600rpm for 2h. Turn off the water bath heating, let the solution temperature drop to room temperature, adjust the pH of the maltodextrin solution to 7, slowly add 2g of adipic anhydride, and react for 3h. Add the previously dissolved gelatin solution to the solution and continue to react for 3h. During the entire reaction process, sodium hydroxide is continuously added to maintain the pH at 7. After the reaction is completed, adjust the pH to 6, pour the product into anhydrous ethanol, precipitate, filter, wash with anhydrous ethanol, and dry for use. Take 0.5g of maltodextrin-based thermosensitive material and dissolve it in 25g of deionized water, stir at 600rpm for 90min to dissolve, add 0.3g of lavender essential oil to the solution, stir for 30min, add 0.25g of Tween 80, stir at 600rpm for 30min, homogenize the mixed solution for 8min, and obtain an essential oil microcapsule emulsion.

[0057] The microcapsule emulsion was divided into 5 groups and applied to the mask cloth respectively, and then placed at 4°C and 32°C for 5 min, 10 min, 15 min, 20 min, and 25 min respectively. Then, it was extracted with cyclohexane and the cumulative release of essential oil was obtained using a UV spectrophotometer. Figure 4 It indicates the cumulative release of essential oil in microcapsules on the mask cloth over time at different temperatures. The results show that the essential oil in the capsule is almost not released at 4°C, and the release rate at 32°C remains high, and the essential oil release rate can reach 78.41% after 25 minutes.

[0058] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A maltodextrin-based temperature-responsive microcapsule, characterized in that: The core material of the microcapsule is natural essential oil, and the wall material of the microcapsule is maltodextrin-based temperature-sensitive material.

2. The maltodextrin-based temperature-responsive microcapsule according to claim 1, characterized in that: The microcapsule uses deionized water as solvent, and its raw materials include: 1-5wt% natural essential oil, 2-10wt% maltodextrin-based temperature-sensitive material, and 1-5wt% surfactant.

3. A maltodextrin-based temperature-responsive microcapsule according to claim 2, characterized in that: The natural essential oil is selected from one or more of lavender essential oil, rosemary essential oil, lemon essential oil, and jasmine essential oil, and the surfactant is selected from one or more of sodium lauryl sulfate, Tween 80, Tween 20, Span 80, and sodium carboxymethyl cellulose.

4. The maltodextrin-based temperature-responsive microcapsule according to claim 2, characterized in that: The maltodextrin-based temperature-sensitive material uses deionized water as a solvent, and its raw materials include 5-30wt% of maltodextrin, 5-10wt% of acid anhydride, 20-50wt% of temperature-sensitive material, 0.1-2wt% of hydrochloric acid, and 0.1-2wt% of sodium hydroxide.

5. The maltodextrin-based temperature-responsive microcapsule according to claim 4, characterized in that: The acid anhydride is a dibasic or higher acid anhydride, and the acid anhydride is selected from one or more of succinic anhydride, glutaric anhydride, adipic anhydride, citric anhydride, polyisobutylene succinic anhydride, and trimellitic anhydride; the temperature-sensitive material is selected from one or more of gelatin, elastin polypeptide, chitosan, hydroxybutyl chitosan, methyl cellulose, and hydroxypropyl methyl cellulose.

6. A method for preparing maltodextrin-based temperature-responsive microcapsules according to any one of claims 1 to 5, characterized in that: The following steps are involved: The maltodextrin-based temperature-sensitive material is dissolved in deionized water and stirred to dissolve, natural essential oil and surfactant are added according to mass percentage and mixed and stirred, and a maltodextrin-based temperature-responsive microcapsule solution is obtained after homogenization, and the microcapsule solution is freeze-dried to obtain a maltodextrin-based temperature-responsive microcapsule powder.

7. The method for preparing maltodextrin-based temperature-responsive microcapsules according to claim 6, characterized in that: The stirring and dissolving time of the maltodextrin-based temperature-sensitive material is 60 to 120 minutes, and the stirring speed is 400 to 600 rpm; after adding the natural essential oil and the surfactant, the material is first stirred at a stirring speed of 400 to 600 rpm for 20 to 30 minutes, and then homogenized for 3 to 8 minutes; the freeze-drying temperature is -50 to -60°C, and the freeze-drying time is 40 to 56 hours.

8. The method for preparing maltodextrin-based temperature-responsive microcapsules according to claim 6, characterized in that: The maltodextrin-based thermosensitive material is prepared by the following method: maltodextrin and thermosensitive material are dissolved in deionized water to obtain maltodextrin solution and thermosensitive material solution respectively; after adjusting the pH of the maltodextrin solution to 6.0-9.0 by adding sodium hydroxide, anhydride is added for reaction, and then the thermosensitive material solution is added for reaction, and during the whole reaction process, sodium hydroxide is added dropwise at the same time so that the pH of the solution is always maintained at 6.0-9.0 during the whole reaction process. After the reaction is completed, hydrochloric acid is added to adjust the pH to 4.5-7.0, the product is poured into anhydrous ethanol, precipitated, filtered, washed with anhydrous ethanol, and dried to obtain the maltodextrin-based thermosensitive material.

9. The method for preparing maltodextrin-based temperature-responsive microcapsules according to claim 8, characterized in that: The DE value of the maltodextrin is 5 to 18; the reaction time after adding the acid anhydride is 180 to 300 minutes; the reaction time after adding the temperature-sensitive material solution and adjusting the pH of the solution is 180 to 300 minutes.

10. Use of the maltodextrin-based temperature-responsive microcapsule according to any one of claims 1 to 5 in the preparation of skin care cosmetics, cotton fabric finishing agents, and food preservative materials.

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