A method for preparing long-acting electric mosquito-repellent incense sheet

Abstract

The invention discloses a method for preparing a long-acting electric mosquito-repellent incense sheet. By weight percentage, 50-80% of mosquito-repellent essential oil, 15-35% of a solubilizing agent and 5-15% of a ferrocene carboxylic acid derivative are uniformly mixed to obtain a mosquito-repellent enhancing liquid, and then pyrethroids are added and loaded on a carrier sheet to obtain the mosquito-repellent enhancing liquid. The electric mosquito-repellent incense sheet has a sustained release property, can uniformly release mosquito-killing components over a long period of time, has a relatively stable volatilization amount, and has a long-acting mosquito-killing effect.

Description

Technical Field

[0001] The invention relates to the technical field of electric mosquito-repellent incense sheets, and more specifically, to a preparation method of a long-acting electric mosquito-repellent incense sheet. Background Art

[0002] Pyrethroid liquids have been maturely used in various mosquito repellent products for repelling and killing mosquitoes, but as a result, mosquitoes' resistance to pyrethroid liquids has gradually increased, and the content of pyrethroid liquids must be limited to a certain range. Therefore, for pyrethroid liquids, the mosquito repellent effect will decrease over time.

[0003] Common synergists on the market include synergistic amine (MGK-264), piperonyl butoxide (S1), octachlorodipropyl ether, piperonyl butoxide, etc., but these synergists are currently commonly used in contact insecticide aerosol products, and are mostly chemically synthesized components, which are not friendly to the environment. The use of some plant-derived ingredients has shown certain synergistic activity to existing pyrethroid liquids, and is environmentally friendly, such as Chinese patent document CN101558770A discloses a mosquito-repellent incense synergist with plant extract eucalyptus oil and cinnamon oil as effective substances, which can be composed of synergistic pesticide compositions with pesticide varieties, configured into mosquito-repellent liquid and applied to mosquito-repellent embryos, and made into mosquito-repellent incense. Its use effect is judged by synergistic test, and is represented by activity coefficient, and activity coefficient is greater than 1, indicating that the mosquito-repellent incense using the synergist has synergistic effect. Chinese patent document CN104938530A discloses a mosquito coil synergist with plant extracts of wintergreen oil, eucalyptus oil, clove oil, peppermint oil and turpentine as effective substances. The activity test data confirms that the mosquito coil synergist has a synergistic effect on a variety of pyrethroid pesticides. However, in actual application, it is found that the volatilization of the agent is significantly attenuated, the volatilization amount is large in the early stage, and the volatilization amount is small in the later stage. The later effect is not ideal for multiple uses, mainly because the above-mentioned synergist and the agent are loaded on the carrier sheet and it is difficult to achieve a uniform release effect.

[0004] Therefore, it is necessary to propose a preparation method of a long-acting electric mosquito coil, which can control the release uniformity and improve the sustainability of mosquito repellent while ensuring the mosquito repellent effect. Summary of the invention

[0005] In view of this, the present invention provides a safe and non-toxic synergist for electric mosquito coils and electric mosquito coils, which can control the release uniformity and thus improve the sustainability of mosquito repelling on the basis of ensuring the mosquito repelling effect.

[0006] The technical solution of the present invention is as follows:

[0007] A method for preparing a long-acting electric mosquito coil comprises the following steps: uniformly mixing 50-80% of mosquito repellent essential oil, 15-35% of a solubilizing agent and 5-15% of a ferrocene carboxylic acid derivative by weight, adding pyrethroid to obtain a mosquito repellent liquid, and loading the mosquito repellent liquid on a carrier sheet to obtain the mosquito repellent liquid.

[0008] In the present invention, the mosquito repellent liquid is loaded on the carrier sheet in an amount of 110-190 mg / sheet.

[0009] In the present invention, the solubilizing agent includes volatile silicone oil and volatile esters.

[0010] Furthermore, the volume ratio of the volatile silicone oil to the volatile esters is 1:(0.5-2).

[0011] Further, the volatile ester is at least one of ethyl formate, propyl formate, methyl acetate, ethyl acetate, propyl acetate and butyl acetate. Preferably, the volatile ester is ethyl acetate.

[0012] In the present invention, the ferrocene carboxylic acid derivative is at least one of ferrocene monoacid, ferrocene diacid, and derivatives thereof.

[0013] In the present invention, the mosquito repellent essential oil includes at least one of lemongrass essential oil, lavender essential oil, peppermint essential oil, clove essential oil and geranium essential oil.

[0014] In the present invention, the pyrethroid is selected from at least one of cypermethrin, transfluthrin, chlorfluthrin, prallethrin, and Es-bioallethrin; preferably, the amount of pyrethroid in the mosquito coil is 13 mg.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The electric mosquito coil obtained by the preparation method of the present invention has a sustained release property, can release mosquito-killing components evenly over a long period of time, has a relatively stable volatilization amount, and has a long-lasting mosquito-killing effect.

[0017] 2. The electric mosquito coil obtained by the preparation method of the present invention uses environmentally friendly ingredients, and the added ferrocene carboxylic acid derivative itself has a camphor smell, which can enhance the mosquito repellent effect. DETAILED DESCRIPTION

[0018] In order to solve the defects in the prior art that the plant-derived synergists only have a synergistic effect but the synergistic effect is not sustainable, and the synergists and agents loaded on the carrier sheet cannot be released stably, resulting in a decreasing trend in the volatilization amount, the present invention introduces a new synergistic ingredient with a certain sustained-release effect, so that the plant synergistic ingredient and the agent have a synergistic effect and have a continuous and uniform mosquito repellent effect.

[0019] The present invention provides a method for preparing a long-acting electric mosquito coil, which specifically comprises the following steps:

[0020] 1. By weight percentage, 50-80% of mosquito repellent essential oil, 15-35% of solubilizer and 5-15% of ferrocene carboxylic acid derivative are mixed evenly to obtain a synergistic solution;

[0021] The mosquito repellent essential oil includes at least one of lemongrass essential oil, lavender essential oil, peppermint essential oil, clove essential oil and geranium essential oil. The solubilizer includes volatile silicone oil and volatile esters, and the volume ratio of the two is 1: (0.5-2); the volatile ester is at least one of ethyl formate, propyl formate, methyl acetate, ethyl acetate, propyl acetate and butyl acetate. Preferably, the volatile ester is ethyl acetate.

[0022] The ferrocene carboxylic acid derivative is selected from ferrocene carboxylic acid and its derivatives with relatively small molecular weight, preferably at least one of ferrocene monoacid, ferrocene diacid, and their derivatives.

[0023] 2. Pyrethroid is added to the synergistic liquid to obtain mosquito repellent liquid; the pyrethroid is selected from at least one of transfluthrin, transfluthrin, chlorfluthrin, prallethrin and Es-bioallethrin.

[0024] 3. The mosquito repellent liquid is loaded on the carrier sheet in an amount of 110-190 mg / piece to obtain an electric mosquito coil sheet, wherein the amount of the pyrethroid added is 13 mg according to the mosquito killing and repelling effect and product standards.

[0025] The design concept of the present invention is that the mosquito repellent essential oil has a synergistic effect on pyrethroids, and the purpose of selecting ferrocene carboxylic acid derivatives is that, on the one hand, under the solubilizing agent system, it can be bonded with the components containing hydroxyl groups in the mosquito repellent essential oil, and as the solubilizing agent continues to volatilize, it can still form a certain network system, thereby forming a sustained-release effect; on the other hand, the unique camphor smell of the ferrocene carboxylic acid derivative itself has a mosquito repellent effect, and is an environmentally friendly ingredient, which is a better choice.

[0026] The following are specific implementation examples of the present invention, which are preferred and detailed descriptions of the present invention. It should be understood that the specific implementation methods described in this specification are only for explaining the present invention, and are not intended to limit the present invention.

[0027] Example 1

[0028] Take 35g of solubilizer (volume ratio of volatile silicone oil to ethyl acetate is 1:2), add 15g of ferrocene monoacid to dissolve, add 50g of lemongrass essential oil and mix well, then add 6.5g of chlorfenapyr and 7g of propylthrin and mix well, and load them on the carrier sheet at an amount of 110mg / sheet to obtain an electric mosquito coil.

[0029] Example 2

[0030] Take 15g of solubilizer (volume ratio of volatile silicone oil to ethyl acetate is 1:0.5) and add 5g of ferrocene dibasic acid to dissolve, add 80g of lavender essential oil and peppermint essential oil and mix well, then add 7.5g of chlorfluanidazole and mix well, and load it on the carrier sheet at an amount of 190mg / sheet to obtain an electric mosquito coil.

[0031] Example 3

[0032] Take 25g of solubilizer (volatile silicone oil and ethyl formate, butyl acetate volume ratio of 1:0.5:0.5), add 5g of ferrocene monoacid and 5g of ferrocene diacid to dissolve, add lemongrass essential oil, lavender essential oil, peppermint essential oil totaling 65g and mix well, then add 3g of chlorfenapyr, 3.5g of prallethrin, and 4.5g of Es-bioallethrin and mix well, and load them on the carrier sheet in an amount of 130mg / sheet to obtain an electric mosquito coil.

[0033] Example 4

[0034] Take 20g of solubilizer (volume ratio of volatile silicone oil to ethyl acetate and butyl acetate is 1:1:0.5), add 5g of ferrocene monoacid and 3g of ferrocene diacid to dissolve, add 72g of clove essential oil and geranium essential oil and mix well, then add 2g of tetrafluthrin, 3g of chlorfluthrin, 3g of propylthrin and 3g of Es-bioallethrin and mix well, and load them on the carrier sheet in an amount of 130mg / sheet to obtain an electric mosquito coil.

[0035] Comparative Example 1

[0036] Take 35g of solubilizer (volume ratio of volatile silicone oil to ethyl acetate is 1:2), add 50g of lemongrass essential oil and mix well, then add 6.5g of chlorfenapyr and 7g of prallethrin and mix well, and load them on the carrier sheet at an amount of 110mg / sheet to obtain an electric mosquito coil.

[0037] Comparative Example 2

[0038] Take 15g of solubilizer (volume ratio of volatile silicone oil to ethyl acetate is 1:0.5), add 80g of lavender essential oil and peppermint essential oil, mix well, then add 7.5g of chlorfluanidazole and mix well, and load it on the carrier sheet at an amount of 190mg / sheet to obtain an electric mosquito coil.

[0039] Comparative Example 3

[0040] Take 25g of solubilizer (volatile silicone oil and ethyl formate, butyl acetate volume ratio of 1:0.5:0.5), add 5g of ferrocene monoacid and 5g of ferrocene diacid to dissolve, then add 3g of chlorfenapyr, 3.5g of propylthrin, and 4.5g of Es-bioallethrin to mix well, and load them on the carrier sheet at an amount of 130mg / sheet to obtain an electric mosquito coil.

[0041] Comparative Example 4

[0042] Take 20g of solubilizer (volatile silicone oil and ethyl acetate, butyl acetate volume ratio of 1:1:0.5), add 5g of ferrocene monoacid and 3g of ferrocene diacid to dissolve, then add 2g of tetrafluthrin, 3g of chlorfluthrin, 3g of propylthrin, and 3g of Es-bioallethrin to mix well, and load them on the carrier sheet at an amount of 130mg / sheet to obtain an electric mosquito coil.

[0043] Comparative Example 5

[0044] Take 20g of solubilizer (volume ratio of volatile silicone oil to ethyl acetate and butyl acetate is 1:1:0.5), add 2g of tetrafluthrin, 3g of chlorfluthrin, 3g of propylthrin and 3g of Es-bioallethrin, mix well, and load them on a carrier sheet at 130mg / sheet to obtain an electric mosquito coil.

[0045] The following are experimental examples of the present invention, and the effectiveness of the electric mosquito coils obtained in the above-mentioned Examples 1-4 and Comparative Examples 1-5 is verified.

[0046] Experimental example

[0047] 1. Test conditions: temperature (26±1)℃, relative humidity 65±10%.

[0048] 2. Test insects: Culex fatigans shall be provided in accordance with the relevant requirements of CB / T 13917-2009.

[0049] 3. Test equipment and instruments:

[0050] Square box device: Made of transparent colorless plexiglass, the inner diameter of length, width and height are all 700mm. There is a small door at the lower corner of one side of the square box. There is also an insect hole on the top of this side, which can be plugged with a rubber plug. Another side is a whole door, which is sealed during testing.

[0051] 4. Test method: Follow the relevant provisions of GB / T 13917.6-2009 "Indoor efficacy test and evaluation of public health insecticides for pesticide registration Part 5: Electric mosquito coils". Use the square box method, and the power-on time is divided into 1h, 3h, 6h, 9h, and 12h for efficacy test. Put 50 Culex pipiens into the self-released insect hole and plug it tightly. After the test insects resume normal activities, put the heater containing the electric mosquito coils to be tested, which has been continuously powered on and pre-ignited to the corresponding time point, into the center of the square box through a small door, immediately close the entire square box device, and start timing. Record the number of test insects knocked down at regular intervals. After each test, clean the test device. Use linear regression programming to calculate its KT50 value.

[0052] 5. Test results:

[0053] The electric mosquito coils described in the above Examples 1-4 and their corresponding Comparative Examples 1-5 were randomly selected to measure the indoor efficacy against Culex pipiens quinquefasciatus. The results are shown in Table 1 below.

[0054] Table 1:

[0055]

[0056] It is not difficult to see from Table 1 that, compared with Comparative Examples 1-5, the KT50 value of the electric mosquito coils in Examples 1-4 does not change much with the extension of the power-on time, and is basically maintained between 5.0-5.8, which can effectively release the mosquito repellent ingredients, the volatilization amount is relatively stable, and the overall mosquito repellent and mosquito killing effect is good. In Comparative Example 1-2, since no ferrocene carboxylic acid or its derivatives were added, the initial KT50 value was lower than that of Example 1-4, but there was a significant fluctuation after 6 hours of power-on, but it reached more than 8 minutes after 12 hours. The possible reason is that in the absence of ferrocene carboxylic acid, it cannot form a combination with the hydroxyl group present in the mosquito repellent essential oil, and cannot form a release resistance, resulting in a release amount that is first high and then low; in the absence of mosquito repellent essential oil, Comparative Example 3-4 also cannot form a sustained-release system, and the release amount is still high at first and then low; Comparative Example 5 does not add mosquito repellent essential oil and ferrocene carboxylic acid (close to the commercially available sample), and the KT50 value is larger than that of Comparative Example 4. The possible reason is that the ferrocene carboxylic acid that is not combined in Example 4 sublimates during the heating process, showing a weak synergistic mosquito repellent effect, resulting in a smaller KT50 value.

[0057] Finally, a few points should be explained. Although the present invention has been described in detail above with general descriptions and specific embodiments, on the basis of the present invention, the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a long-acting electric mosquito-repellent incense sheet, characterized in that: The method comprises the following steps: uniformly mixing 50-80% of mosquito repellent essential oil, 15-35% of solubilizer and 5-15% of ferrocene carboxylic acid derivative by weight, adding pyrethroid to obtain mosquito repellent liquid, and loading the mosquito repellent liquid on a carrier sheet; the ferrocene carboxylic acid derivative is at least one of ferrocene monoacid, ferrocene diacid and derivatives thereof.

2. The preparation method according to claim 1, characterized in that: The mosquito repellent liquid is loaded on the carrier sheet in an amount of 110-190 mg / sheet.

3. The preparation method according to claim 1, characterized in that: The solubilizing agent includes volatile silicone oil and volatile esters.

4. The preparation method according to claim 3, characterized in that: The volume ratio of the volatile silicone oil to the volatile esters is 1:(0.5-2).

5. The preparation method according to claim 3, characterized in that: The volatile ester is at least one of ethyl formate, propyl formate, methyl acetate, ethyl acetate, propyl acetate and butyl acetate.

6. The preparation method according to claim 3, characterized in that: The volatile ester is ethyl acetate.

7. The preparation method according to claim 1, characterized in that: The mosquito repellent essential oil includes at least one of lemongrass essential oil, lavender essential oil, peppermint essential oil, clove essential oil and geranium essential oil.

8. The preparation method according to claim 1, characterized in that: The pyrethroid is at least one of transfluthrin, transfluthrin, chlorfluthrin, prallethrin and Es-bioallethrin.

9. The preparation method according to claim 1, characterized in that: The amount of pyrethroids in the mosquito coil is 13 mg.

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