An antibacterial spinning oil suitable for cellulose acetate used in cigarette filters

Abstract

This invention discloses an antibacterial spinning oil suitable for acetate fibers used in cigarette filters, comprising an emulsifier, mineral oil, water, and an antibacterial agent. Before phase inversion, it is a transparent water-in-oil liquid; after phase inversion, it becomes a white oil-in-water emulsion. Phase inversion occurs in water or water containing the antibacterial agent. The mass ratio of the spinning oil to the water used for phase inversion or water containing the antibacterial agent before phase inversion is (1–49):(99–51). The antibacterial agent is a commercially available water-soluble antibacterial agent, selected from one or more of the following: 4-chloro-3-cresol, dichlorophenoxychlorophenol, bromochlorobisphenol, benzyl chloroethylammonium, benzalkonium chloride, dodecyl dimethyl ethylphenoxyethyl ammonium bromide, guanidine and guanidine polymers, quaternary ammonium salts, silver ions, copper ions, sodium phenylpropionate, nifedipine, dimethyl fumarate, sorbic acid, and dehydroacetic acid. The concentration of the antibacterial agent in water is 0.1 wt%–100 wt%.

Description

Technical Field

[0001] This invention relates to a spinning oil for cellulose acetate, specifically to an antibacterial spinning oil for cellulose acetate used in cigarette filters. Background Technology

[0002] The spinning methods for chemical fibers can be broadly classified into two categories: melt spinning and solution spinning. Spinning oils are auxiliaries used during the spinning process to reduce static electricity and friction coefficients between fibers, ensuring good spinnability and post-processing properties. Cellulose acetate, short for cellulose acetate fiber, is the earliest commercially produced cellulose organic ester derivative. Cellulose acetate is spun using solution spinning, with acetic acid as a solvent and acetic anhydride as an acetylation agent. Esterification occurs under the action of a catalyst to produce cellulose acetate, which is then spun into fibers. Because the molecular structure of cellulose acetate contains a large number of carboxyl and hydroxyl groups, strong intermolecular entanglement is formed, significantly increasing the processing difficulty.

[0003] Currently, cigarette filter rods on the market are mainly made of cellulose acetate tow. In the industrial production process of cellulose acetate tow for cigarette filter rods, due to the long-term operation of the equipment, the mineral oil used in spinning has an excessively high microbial content, resulting in the growth of microbial colonies. The industry uses hydrogen peroxide to achieve the purpose of antibacterial, but in practice, the following problems have been found: (1) The antibacterial effect is not ideal, and there is always the phenomenon of microbial growth, requiring manual cleaning of the oil tank, which is time-consuming and laborious; (2) The hydrogen peroxide remaining in the cellulose acetate tow has strong oxidizing properties, which on the one hand will cause the cellulose acetate to break at high temperature and form shavings, affecting the quality of the cellulose acetate tow; on the other hand, the residual hydrogen peroxide affects the physicochemical properties of the tow, which is not conducive to storage. In addition, in order to be suitable for use in cigarette filter rods, the spinning oil should be colorless, odorless, and non-toxic, and should not affect the flavor of cigarettes.

[0004] Some literature discloses methods to achieve antibacterial effects without using hydrogen peroxide. For example, CN102021824B discloses an antibacterial emulsifier for spinning oils that can inhibit microbial growth. Its specific formula is: "92.7-99.6% emulsifier, 0.2-0.5% sodium benzoate, 0.2%-3.0% nifedipine, 0-1.0% dimethyl fumarate, 0-3.7% calcium propionate, 0-1.5% sorbitol, and 0-0.3% dehydroacetic acid." However, this literature discloses only the emulsifier's technical solution. The emulsifier is only one component in the manufacture of the oil and cannot be directly used in spinning. Adding so many types of antibacterial agents to the emulsifier will affect its emulsifying properties and adversely affect the formulated oil. These antibacterial agents are all water-soluble compounds and cannot be completely dissolved when directly added to a mixture of pure Span 20 and Tween 80. Therefore, the technical solution disclosed in this literature cannot meet the practical needs of large-scale production.

[0005] Therefore, there is an urgent need to find a spinning oil agent that can be applied to large-scale production, has antibacterial effects, and is suitable for cellulose acetate fibers used in cigarette filters. Summary of the Invention

[0006] In order to overcome the above-mentioned technical problems, the purpose of this invention is to provide an antibacterial spinning oil agent for cellulose acetate used in cigarette filters that is simple in composition, easy to operate, and can be applied directly without subsequent compounding.

[0007] The present invention provides an antibacterial spinning oil for cellulose acetate used in cigarette filters, comprising an emulsifier, mineral oil, water and an antibacterial agent. Before phase inversion, the spinning oil is a pale yellow to colorless transparent water-in-oil emulsion, and after phase inversion, it is a white oil-in-water emulsion. The phase inversion is carried out in water or water containing an antibacterial agent. The mass ratio of the spinning oil before phase inversion to the water used for phase inversion or the water used for phase inversion containing an antibacterial agent is (1-49):(99-51).

[0008] Preferably, in the antibacterial spinning oil agent for cellulose acetate used in cigarette filters provided by the present invention, the mass ratio of the spinning oil agent before phase inversion to water used for phase inversion or water containing antibacterial agent used for phase inversion is (1-30):(99-70).

[0009] Preferably, in the antibacterial spinning oil agent for cellulose acetate used in cigarette filters provided by the present invention, the antibacterial agent in the spinning oil agent before phase inversion is a water-soluble antibacterial agent, which is one or more of 4-chloro-3-cresol, dichlorophenoxychlorophenol, bromochlorobisphenol, benzyl chloroethylammonium, benzalkonium chloride, dodecyl dimethyl ethylphenoxyethyl ammonium bromide, guanidine and guanidine polymers, quaternary ammonium salts, silver ions, copper ions, sodium phenylpropionate, nifedipine, dimethyl fumarate, sorbic acid, and dehydroacetic acid. The mass ratio of the antibacterial agent in the spinning oil agent before phase inversion to water in the spinning oil agent before phase inversion is (0.1-100):(99.9-0).

[0010] Preferably, in the antibacterial spinning oil agent for cellulose acetate used in cigarette filters provided by the present invention, the proportion of the pre-phase inverted emulsifier in the pre-phase inverted spinning oil agent is 18wt% to 60wt%, the proportion of the pre-phase inverted mineral oil in the pre-phase inverted spinning oil agent is 30wt% to 80wt%, and the total proportion of the pre-phase inverted water and antibacterial agent in the pre-phase inverted spinning oil agent is 3wt% to 20wt%.

[0011] More preferably, in the antibacterial spinning oil agent for cellulose acetate used in cigarette filters provided by the present invention, the proportion of the pre-phase inverted emulsifier in the pre-phase inverted spinning oil agent is 20wt% to 50wt%, the proportion of the pre-phase inverted mineral oil in the pre-phase inverted spinning oil agent is 45wt% to 80wt%, and the total proportion of the pre-phase inverted water and antibacterial agent in the pre-phase inverted spinning oil agent is 3wt% to 15wt%.

[0012] Preferably, in the antibacterial spinning oil agent for cellulose acetate used in cigarette filters provided by the present invention, the emulsifier is a mixture of any one of food-grade Span 20-50 and any one of food-grade Tween 40-80.

[0013] More preferably, in the antibacterial spinning oil agent for cellulose acetate used in cigarette filters provided by the present invention, the emulsifier mixture further includes one or more of glyceryl monostearate, xylitol anhydride monostearate, polyoxyethylene xylitol anhydride monostearate, and fatty acid sucrose ester.

[0014] Preferably, in the antibacterial spinning oil agent for cellulose acetate used in cigarette filters provided by the present invention, the mineral oil is food-grade white oil.

[0015] Preferably, in the antibacterial spinning oil agent for cellulose acetate used in cigarette filters provided by the present invention, the mass ratio of antibacterial agent to water in the water containing antibacterial agent used for phase inversion of the spinning oil agent is (0.1-100):(99.9-0). The antibacterial agent is one or more of the following: 4-chloro-3-cresol, dichlorophenoxychlorophenol, bromochlorobisphenol, benzyl chloroethylammonium, benzalkonium chloride, dodecyl dimethyl ethylphenoxyethyl ammonium bromide, guanidine and guanidine polymers, quaternary ammonium salts, silver ions, copper ions, sodium phenylpropionate, nifedipine, dimethyl fumarate, sorbic acid, and dehydroacetic acid.

[0016] Furthermore, the present invention also provides a method for preparing the above-mentioned antibacterial spinning oil agent suitable for cellulose acetate fibers used in cigarette filters, comprising the following steps:

[0017] (1) First, dissolve the above antibacterial agent in water according to the above proportion to prepare water containing antibacterial agent; then prepare spinning oil by mixing the above water containing antibacterial agent, emulsifier, and mineral oil according to the above proportion.

[0018] (2) Prepare a spinning oil by mixing the above water, antibacterial agent, emulsifier and mineral oil in the above proportions.

[0019] (3) The spinning oil prepared in (1) or (2) is inverted in water or water containing antibacterial agent.

[0020] The advantages of the technical solution of this invention are: (1) No subsequent compounding is required; it can be directly applied to the spinning of cellulose acetate after phase inversion. (2) The antibacterial agent is a water-soluble compound. The antibacterial agent is added to water to prepare antibacterial water, and then the antibacterial water is mixed with emulsifier and mineral oil to prepare spinning oil. The emulsification effect is good, and the antibacterial spinning oil has few chemical components. (3) Few types of chemicals are used, the operation is simple, the safety performance is high, and it is suitable for large-scale industrial continuous production. (4) The spinning oil after phase inversion is milky white, odorless and non-toxic, with good antibacterial effect, suitable for processing cellulose acetate for cigarettes, and does not affect the flavor of cigarettes. (5) The spinning oil before phase inversion does not separate into layers or precipitate, and can be stored for a long time. Detailed Implementation

[0021] This invention provides an antibacterial spinning oil for cellulose acetate used in cigarette filters, comprising an emulsifier, an oil, water, and an antibacterial agent. Before phase inversion, the spinning oil is a pale yellow to colorless transparent water-in-oil emulsion. Phase inversion occurs in water, antibacterial water, or water containing an antibacterial agent, resulting in a white oil-in-water emulsion after phase inversion. After phase inversion, it can be directly applied to the spinning process.

[0022] Regarding emulsifiers. The emulsifier is a mixture of any one of food-grade Span 20-50 and any one of Tween 40-80, and may also contain one or more of other food emulsifiers, such as glyceryl monostearate, xylitol anhydride monostearate, polyoxyethylene xylitol anhydride monostearate, and fatty acid sucrose esters.

[0023] Before phase inversion, the emulsifier accounts for 18 wt% to 60 wt% of the spinning oil. If the proportion is less than 18 wt%, a stable emulsion cannot be formed. If it exceeds 60 wt%, the viscosity and density of the spinning oil will not meet the requirements, and phase inversion will not be possible in subsequent operations. A further preferred proportion is 20 wt% to 50 wt%.

[0024] Regarding mineral oil, food-grade white oil is preferred. Commercially available mineral oils are colorless to yellow or brown transparent liquids. Before phase inversion, the mineral oil content in the spinning oil is 30wt% to 80wt%; if it is less than 30wt%, a stable water-in-oil emulsion cannot be formed; if it is more than 80wt%, phase inversion cannot be performed in subsequent operations to form a usable spinning oil; a further preferred ratio is 45wt% to 80wt%.

[0025] Regarding water containing antibacterial agents: Preparation of water containing antibacterial agents: Add a water-soluble antibacterial agent to water to prepare water with an antibacterial agent concentration of 0.1 wt% to 100 wt%. Before phase inversion, the proportion of water containing antibacterial agents in the spinning oil is 3 wt% to 20 wt%, more preferably 3 wt% to 15 wt%. If water is not prepared to contain antibacterial agents, and water and antibacterial agents can exist independently, then the total proportion of antibacterial agents and water in the spinning oil before phase inversion is 3 wt% to 20 wt%, more preferably 3 wt% to 15 wt%.

[0026] Regarding antibacterial agents: Antibacterial agents can be selected from commercially available cosmetic phenols and their derivatives, food preservatives, or medical and hygiene disinfectants. Examples include one or more of the following: 4-chloro-3-methylphenol, dichlorophenoxychlorophenol, bromochlorobisphenol, benzyl chloroethylammonium, benzalkonium chloride, dodecyl dimethyl ethylphenoxyethyl ammonium bromide, guanidine and guanidine polymers, quaternary ammonium salts, silver ion compounds, copper ion compounds, sodium phenylpropionate, nifedipine, dimethyl fumarate, sorbic acid, and dehydroacetic acid.

[0027] Regarding the ratio of spinning oil before phase inversion to water for phase inversion or water containing antibacterial agent for phase inversion, the mass ratio of the two is (1-49):(99-51), preferably (1-30):(99-70).

[0028] The above-mentioned spinning oil is applied as follows: the prepared light yellow to colorless transparent water-in-oil spinning oil is directly poured into water or water containing antibacterial agent to perform phase inversion. The spinning oil after phase inversion is water-in-oil type, milky white, and can be used directly by the user.

[0029] Example 1

[0030] An antibacterial spinning oil for cellulose acetate used in cigarette filters comprises an emulsifier, an antibacterial water, and a mineral oil, wherein phase inversion occurs in the antibacterial water.

[0031] Preparation of antibacterial water: Select a commercially available quaternary ammonium salt antibacterial agent, which is a colorless liquid. Add the selected quaternary ammonium salt antibacterial agent liquid to water to prepare an antibacterial water with an antibacterial agent content of 0.1 wt%.

[0032] The emulsifier is a mixture of food-grade Span 50 and food-grade Tween 80, and the mineral oil is food-grade white oil. The prepared antibacterial water, the selected emulsifier, and the food-grade white oil are mixed to form a spinning oil. The antibacterial water accounts for 20 wt% of the prepared spinning oil before phase inversion, the emulsifier accounts for 18 wt%, and the mineral oil accounts for 62 wt%. The mass ratio of the spinning oil before phase inversion to the antibacterial water used for phase inversion is 1:99.

[0033] Before phase inversion, the spinning oil was a pale yellow, transparent liquid without any suspended matter or sediment. Before phase inversion, it was a water-in-oil emulsion; after phase inversion, it became an oil-in-water emulsion, appearing milky white. Neither the spinning oil before nor after phase inversion showed any stratification after one month of storage.

[0034] Example 2

[0035] Preparation of antibacterial solution: A commercially available guanidine antibacterial agent is selected. Guanidine antibacterial agents are colorless liquids. The selected guanidine antibacterial agent liquid is added to water to prepare an antibacterial solution with an antibacterial agent content of 50 wt%.

[0036] The emulsifier is a mixture of food-grade Span 50, food-grade Tween 80, and glyceryl monostearate, and the mineral oil is food-grade white oil. The prepared antibacterial water, the selected emulsifier, and the food-grade white oil are mixed to formulate a spinning oil. The antibacterial water accounts for 3 wt% of the prepared spinning oil before phase inversion, the emulsifier accounts for 20 wt%, and the mineral oil accounts for 77 wt%.

[0037] The mass ratio of the spinning oil before phase inversion to the antibacterial water used for phase inversion was 5:95. The spinning oil before phase inversion was a pale yellow transparent liquid without any suspended matter or sediment. It was a water-in-oil emulsion before phase inversion, while the spinning oil after phase inversion was an oil-in-water emulsion and appeared milky white. Neither the spinning oil before nor after phase inversion showed any stratification after being left for one month.

[0038] Example 3

[0039] An antibacterial spinning oil for cellulose acetate used in cigarette filters comprises an emulsifier, an antibacterial agent, water, and mineral oil. The emulsifier is a mixture of food-grade Span 30 and food-grade Tween 60, accounting for 60 wt% of the spinning oil before phase inversion. The mineral oil is food-grade white oil, accounting for 35 wt% of the spinning oil before phase inversion. The total proportion of the antibacterial agent and water in the spinning oil before phase inversion is 5 wt%. The antibacterial agent is dodecyl dimethyl ethylphenoxyethyl ammonium bromide.

[0040] Preparation method of spinning oil before and after phase inversion: (1) Mix 60 wt% emulsifier, 35 wt% food-grade white oil, 6 wt% water and dodecyl dimethyl ethylphenoxyethyl ammonium bromide antibacterial agent to prepare spinning oil, wherein the mass ratio of antibacterial agent to water is 2:98. (2) Invert the prepared spinning oil in water, wherein the mass percentage of spinning oil before phase inversion to water before phase inversion is 40:60.

[0041] Before phase inversion, the antibacterial spinning oil was a pale yellow, transparent liquid without any suspended matter or sediment. Before phase inversion, the spinning oil was a water-in-oil emulsion, while after phase inversion, it became an oil-in-water emulsion, appearing milky white. Neither the spinning oil before nor after phase inversion showed any stratification after one month of storage.

[0042] Example 4

[0043] The antibacterial agents selected are silver ion and copper ion antibacterial agents. The emulsifier is a mixture of food-grade Span 20, food-grade Tween 40, and polyoxyethylene xylitol anhydride monostearate. A spinning oil is prepared by combining 45 wt% emulsifier, 45 wt% food-grade white oil, 10 wt% water, and the silver ion antibacterial agent, with the antibacterial agent to water ratio being 70 wt%. The prepared spinning oil is then subjected to phase inversion in a solution containing the antibacterial agent to obtain a spinning oil that can be directly used in the spinning process. The antibacterial agent used for phase inversion is a copper ion antibacterial agent, with an antibacterial agent to water mass ratio of 0.1:99.9; the mass percentage of the spinning oil before phase inversion to the antibacterial agent-containing water used for phase inversion is 30:70.

[0044] Before phase inversion, the antibacterial spinning oil was a pale yellow, transparent liquid without any suspended matter or sediment. Before phase inversion, the spinning oil was a water-in-oil emulsion, while after phase inversion, it became an oil-in-water emulsion, appearing milky white. After one month of storage, no stratification was observed in either the pre- or post-phase inversion spinning emulsions.

[0045] Example 5

[0046] The antibacterial agents used are commercially available sodium phenylpropionate and nifedipine ester antibacterial agents. The emulsifier is a mixture of food-grade Span 40, food-grade Tween 50, and xylitol anhydride monostearate. The mineral oil used is food-grade white oil. A spinning oil is prepared by combining 50 wt% emulsifier, 35 wt% food-grade white oil, 15 wt% water, and the antibacterial agent, with a mass ratio of antibacterial agent to water of 15:85. The prepared spinning oil is then subjected to phase inversion in antibacterial water to obtain a spinning oil that can be directly used in the spinning process. The concentration of the antibacterial water used for phase inversion is 0.1 wt%, and the mass percentage of the spinning oil before phase inversion to the water used for phase inversion is 20:80.

[0047] The spinning oil after phase inversion is an oil-in-water type and is milky white. After one month of storage, no stratification occurred in the spinning emulsion before and after phase inversion.

[0048] Example 6

[0049] The antibacterial agent used is commercially available dimethyl fumarate and dehydroacetic acid-based antibacterial agent. The emulsifier used is a mixture of food-grade Span 30, food-grade Tween 40, and fatty acid sucrose esters. The mineral oil used is food-grade white oil. A spinning oil is prepared by combining 60 wt% emulsifier, 30 wt% food-grade white oil, 10 wt% water, and the antibacterial agent dimethyl fumarate, with a mass ratio of dimethyl fumarate to water of 30:70. The prepared spinning oil is then subjected to phase inversion in antibacterial water to obtain a spinning oil that can be directly used in the spinning process. The concentration of the antibacterial water used for phase inversion is 20 wt%, and the antibacterial agent in the antibacterial water used for phase inversion is a commercially available dehydroacetic acid-based antibacterial agent; the mass percentage of the spinning oil before phase inversion to the antibacterial water used for phase inversion is 40:60.

[0050] The spinning oil after phase inversion is an oil-in-water type and is milky white. After one month of storage, no stratification occurred in the spinning emulsion before and after phase inversion.

[0051] Example 7

[0052] The transparent spinning oils prepared in Examples 1 to 6 were tested according to QB / T 2738-2012 "Evaluation Method for Antibacterial and Bacteriostatic Effects of Daily Chemical Products", and the test results are shown in Table 1.

[0053] Table 1. Results of antibacterial performance tests of the spinning oils prepared in Examples 1-6.

[0054]

[0055] According to QB / T 2738-2012 "Evaluation Method for Antibacterial and Bacteriostatic Effects of Daily Chemical Products", a product with an antibacterial rate of 50% to 90% has an antibacterial effect; a product with an antibacterial rate of 90% or more has a strong antibacterial effect.

[0056] It is evident that the pale yellow spinning oil prepared in Examples 1-6 exhibits strong antibacterial activity. Furthermore, the spinning oil provided by this invention remains stable both before and after phase inversion, without stratification, and its viscosity, measured at 37.8°C, is between 60 and 70 mmHg. 2 Within the range of / s, it meets the requirements for convenient subsequent operations.

Claims

1. An antibacterial spinning oil for cellulose acetate used in cigarette filters, comprising an emulsifier, mineral oil, water, and an antibacterial agent, characterized in that... The antibacterial agent is a water-soluble antibacterial agent. Before phase inversion, the spinning oil is a pale yellow to colorless transparent water-in-oil emulsion, and after phase inversion, it becomes a white oil-in-water emulsion. Phase inversion is carried out in water or water containing the antibacterial agent. The mass ratio of the spinning oil before phase inversion to the water used for phase inversion or the water containing the antibacterial agent used for phase inversion is (1-49):(99-51). The emulsifier is a mixture of any one of food-grade Span 20-50 and any one of food-grade Tween 40-80. The emulsifier before phase inversion... The proportion of the agent in the spinning oil before phase inversion is 18wt% to 60wt%, the proportion of the mineral oil in the spinning oil before phase inversion is 30wt% to 80wt%, the total proportion of water and antibacterial agent in the spinning oil before phase inversion is 3wt% to 20wt%, and the mass ratio of antibacterial agent to water in the spinning oil before phase inversion is (0.1 to 100): (99.9 to 0). The spinning oil is prepared by the following steps: (1) First, dissolve the water-soluble antibacterial agent in the water according to the specified ratio to prepare the water containing the antibacterial agent; Then, the water containing the antibacterial agent, the emulsifier, and the mineral oil are prepared in the specified proportions to form the spinning oil agent; (2) The water, the water-soluble antibacterial agent, the emulsifier and the mineral oil are prepared into the spinning oil agent according to the specified ratio; (3) The spinning oil prepared in (1) or (2) is subjected to phase inversion in the water or the water containing the antibacterial agent.

2. The antibacterial spinning oil agent for cellulose acetate used in cigarette filters as described in claim 1, characterized in that... The mass ratio of the spinning oil before phase inversion to the water used for phase inversion or the water containing antibacterial agent for phase inversion is (1-30):(99-70).

3. The antibacterial spinning oil agent for cellulose acetate used in cigarette filters as described in claim 1, characterized in that... The water-soluble antibacterial agent is one or more of the following: 4-chloro-3-cresol, dichlorophenoxychlorophenol, bromochlorobisphenol, benzyl chloroethylammonium, benzalkonium chloride, dodecyl dimethyl ethylphenoxyethyl ammonium bromide, guanidine and guanidine polymers, quaternary ammonium salts, silver ions, copper ions, sodium phenylpropionate, Nepal gold ester, dimethyl fumarate, sorbic acid, and dehydroacetic acid.

4. The antibacterial spinning oil agent for cellulose acetate used in cigarette filters as described in claim 1, characterized in that... The pre-phase emulsifier accounts for 20wt% to 50wt% of the pre-phase spinning oil, the pre-phase mineral oil accounts for 45wt% to 80wt% of the pre-phase spinning oil, and the pre-phase water and antibacterial agent account for 3wt% to 15wt% of the pre-phase spinning oil.

5. The antibacterial spinning oil agent for cellulose acetate used in cigarette filters as described in claim 4, characterized in that... The emulsifier mixture may also contain one or more of the following: glyceryl monostearate, xylitol anhydride monostearate, polyoxyethylene xylitol anhydride monostearate, and fatty acid sucrose esters.

6. The antibacterial spinning oil agent for cellulose acetate used in cigarette filters as described in claim 1, characterized in that... The mineral oil is food-grade white oil.

7. The antibacterial spinning oil agent for cellulose acetate used in cigarette filters as described in claim 1, characterized in that... In the water containing an antibacterial agent used for phase inversion of the spinning oil, the mass ratio of the antibacterial agent to the water is (0.1–100): (99.9~0), wherein the antibacterial agent is one or more of the following: 4-chloro-3-cresol, dichlorophenoxychlorophenol, bromochlorobisphenol, benzyl chloroethylammonium, benzalkonium chloride, dodecyl dimethyl ethylphenoxyethyl ammonium bromide, guanidine and guanidine polymers, quaternary ammonium salts, silver ions, copper ions, sodium phenylpropionate, nifedipine, dimethyl fumarate, sorbic acid, and dehydroacetic acid.

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