Composition having mosquito-repelling effect and preparation method therefor

Abstract

The present invention belongs to the technical field of insecticides and the manufacturing thereof, and in particular relates to a composition having a mosquito-repelling effect and a preparation method therefor. The composition is composed of a polyester fabric or non-woven fabric coated with a finishing liquid and a frame for fixing, wherein the finishing liquid comprises the following raw materials: pyrethroid, a co-solvent, an emulsifier, a thickening and stabilizing agent, an antioxidant, an ultraviolet absorber and water, the thickening and stabilizing agent being a mixture of sodium silicate, sodium carboxymethyl cellulose and polyvinylpyrrolidone. Hung in a well-ventilated environment, the composition of the present invention can, without any additional heat source, power supply or wind source, volatilize an insecticide into the air in a stable and long-lasting manner, thereby achieving a mosquito-repelling effect; moreover, the composition has long-lasting efficacy, providing a persistent mosquito-repelling effect for 60-100 days once opened.

Description

A composition with mosquito-repellent effect and its preparation method Technical Field

[0001] This invention belongs to the field of insecticides and their manufacturing technology, specifically relating to a composition with mosquito-repellent effect and its preparation method. Background Technology

[0002] Pyrethroids are a class of broad-spectrum insecticides that can control a variety of pests and are widely used for the control of sanitary pests, especially flying pests such as mosquitoes and flies. To achieve sustained pest control in a space, pyrethroids need to be continuously released into the air. The common method is to heat the pyrethroids to induce a continuous release over a certain period, as seen in products like mosquito coils, electric mosquito mats, and electric mosquito liquids. However, these products require high temperatures for pyrethroid release, resulting in high energy consumption and potential safety hazards. Therefore, methods that release pyrethroids at room temperature offer advantages such as safety and ease of use. At room temperature, this can be achieved by placing a carrier loaded with pyrethroids on a hanging device, allowing for natural release; another method is to use a fan to blow airflow over the carrier, increasing the release rate.

[0003] Chinese invention patent application CN101702914A discloses a method for preparing filaments by melt-mixing polyethylene resin and an insect control agent (pesticide) at 160°C to 300°C. These filaments can be further processed into net-like, rope-like, or yarn-like structures for controlling arthropod pests at room temperature. The preferred insect control agent for this invention has a vapor pressure of less than 1 × 10⁻⁶ at 25°C. -6 mmHg of pyrethroid insecticides. Materials produced by this melt-mixing method require the insecticide to migrate from the resin material to the resin surface before being released. The release process is very slow, making it impossible to achieve a spatial insect repellent effect. It can only be used for contact-type barrier insect control.

[0004] Chinese invention patent application CN104273158A discloses a composition for controlling the release of pyrethroids, which can achieve stable release of pyrethroids under room temperature conditions for space pest control, especially for the control of flying pests. The wax used in this invention as a substance to control insecticide release is difficult to achieve. Wax is an oily solid at room temperature, which easily encapsulates the insecticide, preventing its release. Adding low-volatility solvents also hinders release, reducing the mosquito-repellent effect. Furthermore, the invention does not mention the manufacturing process of this composition, making mass production impossible.

[0005] α-Ethylene-phenylacetaldehyde, also known as 2-phenyl-2-butenal, is a colorless liquid. It has a musty, floral, honey, cocoa, and black tea-like aroma, and is naturally found in the aroma of black tea. According to the food additive standard GB2760-2014, it is a permitted synthetic flavoring agent for food use.

[0006] Chinese invention patent application CN116868998A discloses any one of the following uses (i) to (ii) of α-ethylidene-phenylacetaldehyde or its tautomers and cis-trans isomers: (i) use as a mosquito repellent; (ii) use in the preparation of compositions or products for mosquito repellency. This invention discovers that α-ethylidene-phenylacetaldehyde has a significant mosquito-repellent effect, preventing mosquito bites by placing or applying α-ethylidene-phenylacetaldehyde around the environment as a potent mosquito repellent. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a composition with mosquito-repellent effects and a method for preparing the same. The composition of this invention can stably and effectively release insecticides into the air, thereby achieving a mosquito-repellent effect. Furthermore, the preparation process is simple and easy to implement, enabling large-scale production.

[0008] To achieve the above-mentioned objectives of this invention, the specific technical solution adopted by this invention is as follows:

[0009] A composition with mosquito-repellent effect, the composition comprising a polyester or non-woven fabric coated with a finishing liquid and a frame for fixing;

[0010] The finishing liquid contains the following raw materials: pyrethroids, cosolvents, emulsifiers, thickeners and stabilizers, binders, antioxidants, UV absorbers, and water. The thickener and stabilizer is a mixture of sodium silicate, sodium carboxymethyl cellulose, and polyvinylpyrrolidone.

[0011] Preferably, the mass ratio of sodium silicate, sodium carboxymethyl cellulose and polyvinylpyrrolidone is 1:3-5:3-5.

[0012] Preferably, the raw materials of the finishing solution, by mass percentage, include: 1%-40% pyrethroids, 1%-40% cosolvents, 3%-5% emulsifiers, 5%-8% thickeners and stabilizers, 5-10% binders, 1%-3% antioxidants, 1%-3% UV absorbers, and the balance being water.

[0013] Preferably, the finishing solution also includes α-ethylidene-phenylacetaldehyde as a raw material.

[0014] More preferably, the raw materials of the finishing liquid, by mass percentage, include: 1%-40% pyrethroids, 1%-40% α-ethylidene-phenylacetaldehyde, 20%-30% co-solvents, 3%-5% emulsifiers, 5%-8% thickeners and stabilizers, 5-10% binders, 1%-3% antioxidants, 1%-3% UV absorbers, and the balance being water.

[0015] Preferably, the pyrethroid is selected from one or more of tetrafluorobenzyl, tetrafluorobenzyl, heptafluorobenzyl, tetrafluorobenzyl, methoxybenzylflufenoxuron, and dextromethorphan; the cosolvent is selected from any one of ethylene glycol, ethyl acetate, ethyl formate, and dipropylene glycol dimethyl ether.

[0016] Preferably, the emulsifier is a mixture of polyoxyethylene hydrogenated castor oil and sodium dodecyl sulfate, wherein the mass ratio of the polyoxyethylene hydrogenated castor oil to sodium dodecyl sulfate is 1:1-3.

[0017] Preferably, the adhesive is JB-30 acrylic emulsion; the ultraviolet absorber is selected from one or more of ultraviolet absorbers UV-0, UV-531, and UV-9.

[0018] By adding a water-based polyurethane adhesive during the preparation of the finishing solution, the binding force between the active ingredients and the fabric is significantly improved, thereby significantly enhancing the mosquito-repellent durability of the fabric treated with the finishing solution.

[0019] Preferably, the antioxidant is a mixture of propyl gallate and 2,6-di-tert-butyl-p-cresol, wherein the mass ratio of propyl gallate to 2,6-di-tert-butyl-p-cresol is 1:3-4.

[0020] The present invention also relates to a method for preparing the above-mentioned composition, comprising the following steps:

[0021] (1) Mix the cosolvent with pyrethroid and α-ethylidene-phenylacetaldehyde, add emulsifier, stir, and obtain mixture 1;

[0022] (2) Mix mixture 1, adhesive, antioxidant, ultraviolet absorber, thickening stabilizer and water to obtain finishing solution;

[0023] (3) Immerse the polyester fabric in the finishing solution, then pass it through the pressure roller, dry it, and cut it to obtain the polyester fabric coated with the finishing solution.

[0024] (4) Place the polyester or non-woven fabric coated with the finishing liquid into the frame that serves to fix it, and fasten it to obtain the composition.

[0025] Preferably, the immersion time in step (3) is 1-2 minutes, the pressure of the pressure roller is 0.1 MPa-0.3 MPa, the drying temperature is 80℃-100℃, and the area of ​​the cut polyester fabric is 100 cm². 2 -200cm 2 The weight is 200g / m 2 -300g / m 2 .

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The composition of the present invention does not require an additional heat source, power source or air source. Simply hang the composition in an air-circulating environment to stably and effectively volatilize the insecticide into the air, thereby achieving the effect of repelling mosquitoes. Moreover, the effect lasts for a long time, and can repel mosquitoes for 60-100 days after opening.

[0028] (2) By adding specific thickeners, stabilizers and emulsifiers, the composition obtained by this invention has a more stable mosquito repellent effect, reduces the impact of transportation and storage on the product when the packaging is not opened, and extends the shelf life of the product after the packaging is opened.

[0029] (3) In this invention, tetrafluorobenzene and α-ethylidene phenylacetaldehyde are used as mosquito repellent active ingredients at the same time, and the two have a synergistic effect, resulting in a more significant mosquito repellent effect.

[0030] (4) The preparation process of the composition of the present invention is simple and easy to implement, suitable for large-scale production, and the product has no irritating odor. During the use of the composition, it has no impact on people's normal life and is safe and harmless to use. Attached Figure Description

[0031] Figure 1 is a liquid chromatogram of the active ingredient content in the polyester fabric of Example 1. Detailed Implementation

[0032] The present invention will be further described in detail below with reference to specific embodiments. The following embodiments are not intended to limit the present invention, but only to illustrate the present invention. Unless otherwise specified, the experimental methods used in the following embodiments are generally performed under conventional conditions. Unless otherwise specified, the materials and reagents used in the following embodiments are commercially available.

[0033] Example 1

[0034] A composition with mosquito-repellent effect, the composition comprising a polyester fabric coated with a finishing liquid and a perforated, hangable plastic shell;

[0035] The finishing solution, by mass percentage, consists of: 30% tetrafluorobenzene, 25% dipropylene glycol dimethyl ether, 4% emulsifier (polyoxyethylene hydrogenated castor oil and sodium dodecyl sulfate in a mass ratio of 1:2), 7% thickener and stabilizer (sodium silicate, sodium carboxymethyl cellulose and polyvinylpyrrolidone in a mass ratio of 1:4:4), 8% binder (JB-30 acrylic emulsion), 2% antioxidant (propyl gallate and 2,6-di-tert-butyl-p-cresol in a mass ratio of 1:3), 2% UV absorber UV-531, and 22% water.

[0036] The preparation method of the above composition includes the following steps:

[0037] (1) Mix dipropylene glycol dimethyl ether with tetrafluorobenzene, add emulsifier, stir evenly to obtain mixture 1;

[0038] (2) Mix mixture 1, adhesive, antioxidant, ultraviolet absorber, thickening stabilizer and water evenly to obtain finishing solution;

[0039] (3) Immerse the polyester fabric in the finishing solution for 1.5 minutes, then pass it through a pressure roller at a pressure of 0.2 MPa, dry at 90°C, and cut to 150 cm lengths. 2 The weight is 250g / m 2 To obtain polyester and fabric coated with finishing solution;

[0040] (4) Place the polyester fabric coated with finishing liquid into a perforated, hangable plastic shell and fasten it to obtain the composition.

[0041] The content of active ingredients in polyester fabric was tested using normal phase liquid chromatography (HPLC), with isooctane as the mobile phase and extractant. The HPLC chromatogram is shown in Figure 1.

[0042] Example 2

[0043] A composition with mosquito-repellent effect, the composition comprising a polyester fabric coated with a finishing liquid and a perforated, hangable plastic shell;

[0044] The finishing solution, by mass percentage, consists of: 25% tetrafluorobenzyl ester, 5% α-ethylidene-phenylacetaldehyde, 25% dipropylene glycol dimethyl ether, 4% emulsifier (polyoxyethylene hydrogenated castor oil and sodium dodecyl sulfate in a mass ratio of 1:2), 7% thickener and stabilizer (sodium silicate, sodium carboxymethyl cellulose and polyvinylpyrrolidone in a mass ratio of 1:4:4), 8% binder (JB-30 acrylic emulsion), 2% antioxidant (propyl gallate and 2,6-di-tert-butyl-p-cresol in a mass ratio of 1:3), 2% UV absorber UV-531, and 22% water.

[0045] The preparation method of the above composition includes the following steps:

[0046] (1) Mix dipropylene glycol dimethyl ether, tetrafluorobenzenepyrin and α-ethylidene-phenylacetaldehyde, add emulsifier, stir evenly to obtain mixture 1;

[0047] (2) Mix mixture 1, antioxidant, ultraviolet absorber, thickening stabilizer and water evenly to obtain finishing solution;

[0048] (3) Immerse the polyester fabric in the finishing solution for 1.5 minutes, then pass it through a pressure roller at a pressure of 0.2 MPa, dry at 90°C, and cut to 150 cm lengths. 2 The weight is 250g / m 2 The resulting polyester fabric coated with the finishing solution was obtained.

[0049] (4) Place the polyester fabric coated with finishing liquid into a perforated, hangable plastic shell and fasten it to obtain the composition.

[0050] Example 3

[0051] A composition with mosquito-repellent effect, the composition comprising a polyester fabric coated with a finishing liquid and a perforated, hangable plastic shell;

[0052] The finishing solution, by mass percentage, consists of: 40% tetrafluoroethylene, 1% α-ethylidene phenylacetaldehyde, 20% dipropylene glycol dimethyl ether, 3% emulsifier (polyoxyethylene hydrogenated castor oil and sodium dodecyl sulfate in a 1:1 mass ratio), 5% thickener and stabilizer (sodium silicate, sodium carboxymethyl cellulose and polyvinylpyrrolidone in a 1:3:3 mass ratio), 5% binder (JB-30 acrylic emulsion), 1% antioxidant (propyl gallate and 2,6-di-tert-butyl-p-cresol in a 1:4 mass ratio), 1% UV absorber UV-531, and 24% water.

[0053] The preparation method of the above composition includes the following steps:

[0054] (1) Mix dipropylene glycol dimethyl ether, tetrafluorobenzenepyrin and α-ethylidene-phenylacetaldehyde, add emulsifier, stir evenly to obtain mixture 1;

[0055] (2) Mix mixture 1, adhesive, antioxidant, ultraviolet absorber, thickening stabilizer and water evenly to obtain finishing solution;

[0056] (3) Immerse the polyester fabric in the finishing solution for 2 minutes, then pass it through a pressure roller at a pressure of 0.3 MPa, dry at 100°C, and cut to 200cm lengths. 2 The weight is 300g / m 2 The resulting polyester fabric coated with the finishing solution was obtained.

[0057] (4) Place the polyester fabric coated with finishing liquid into a perforated, hangable plastic shell and fasten it to obtain the composition.

[0058] Example 4

[0059] A composition with mosquito-repellent effect, the composition comprising a polyester fabric coated with a finishing liquid and a perforated, hangable plastic shell;

[0060] The finishing solution, by mass percentage, consists of: 5% tetrafluorobenzyl ester, 30% α-ethylhexyl phenylacetaldehyde, 30% ethylene glycol, 5% emulsifier (polyoxyethylene hydrogenated castor oil and sodium dodecyl sulfate in a mass ratio of 1:3), 8% thickener and stabilizer (sodium silicate, sodium carboxymethyl cellulose and polyvinylpyrrolidone in a mass ratio of 1:5:5), 10% binder (JB-30 acrylic emulsion), 3% antioxidant (propyl gallate and 2,6-di-tert-butyl-p-cresol in a mass ratio of 1:3), 3% UV absorber UV-9, and 6% water.

[0061] The preparation method of the above composition includes the following steps:

[0062] (1) Mix dipropylene glycol dimethyl ether, tetrafluorobenzenepyrin and α-ethylidene-phenylacetaldehyde, add Tween-80, stir evenly to obtain mixture 1;

[0063] (2) Mix mixture 1, adhesive, antioxidant, ultraviolet absorber, thickening stabilizer and water evenly to obtain finishing solution;

[0064] (3) Immerse the polyester fabric in the finishing solution for 1 minute, then pass it through a pressure roller at a pressure of 0.1 MPa, dry at 80°C, and cut to 100cm lengths. 2 The weight is 200g / m 2 The resulting polyester fabric coated with the finishing solution was obtained.

[0065] (4) Place the polyester fabric coated with finishing liquid into a perforated, hangable plastic shell and fasten it to obtain the composition.

[0066] Comparative Example 1

[0067] The only difference between this comparative example and Example 2 is that the active ingredients in the finishing solution are different.

[0068] By mass percentage, the active ingredient added in this comparative example is: 0% tetrafluorobenzyl ester and 30% α-ethylidene-phenylacetaldehyde.

[0069] Comparative Examples 2-5

[0070] The only difference between Comparative Examples 2-5 and Example 2 is the composition of the thickening stabilizer. The specific composition and mass of the thickening stabilizer in Comparative Examples 2-5 are shown in Table 1.

[0071] Table 1 shows the mass ratios of sodium silicate, sodium carboxymethyl cellulose, and polyvinylpyrrolidone in Comparative Examples 2-5.

[0072] Comparative Example 6

[0073] The only difference between this comparative example and Example 2 is the emulsifier. In this comparative example, the emulsifier is only polyoxyethylene hydrogenated castor oil.

[0074] Comparative Example 7

[0075] The only difference between this comparative example and Example 2 is the emulsifier. In this comparative example, the emulsifier is only sodium dodecyl sulfate.

[0076] Effect test

[0077] Test Example 1: Mosquito Repellent Effect Test

[0078] Biological testing method: Referring to the test method of GB / T13917.6-2009, the box method was used. In a 70cm×70cm×70cm transparent glass box, 50 test mosquitoes were collected and placed into the box through the release port for each test. After the test mosquitoes resumed normal activity, the mixtures from different time points were placed into the center of the glass box through the small door, and the fan was turned on to maintain an airflow speed of 0.2±0.05m / s. The entire box device was immediately sealed, and the time was started. The number of test mosquitoes knocked down was recorded at regular intervals. The observation period was 20 minutes. The test was repeated three times. After each test, the test device was cleaned. The KT50 value was calculated, and the test results are shown in Table 2.

[0079] Table 2 KT50 values ​​of the compositions of Examples 1-4 and Comparative Examples 1-7

[0080] The active ingredient in Example 1 is only tetrafluorobenzyl ester, and the active ingredient in Comparative Example 1 is only α-ethylidene-phenylacetaldehyde. According to the data in Table 2, the mosquito repellent effect is best when both tetrafluorobenzyl ester and α-ethylidene-phenylacetaldehyde are added in Example 2, indicating that there is a synergistic effect between tetrafluorobenzyl ester and α-ethylidene-phenylacetaldehyde.

[0081] The only difference between Comparative Examples 2-5 and Example 2 is the thickening and stabilizing agent. The composition of the thickening and stabilizing agent has a significant impact on the release of the active ingredient. When sodium silicate, sodium carboxymethyl cellulose, and polyvinylpyrrolidone are present simultaneously, the active ingredient can be released stably, resulting in better effects. In addition, the only difference between Comparative Examples 6-7 and Example 2 is the composition of the emulsifier. The emulsifier in this invention is a mixture of polyoxyethylene hydrogenated castor oil and sodium dodecyl sulfate. The two have a synergistic effect, which can stably and effectively release the active ingredient and achieve a better mosquito repellent effect.

[0082] Test Example 2 Anti-mildew Performance Test

[0083] The anti-mildew properties of the compositions in Examples 1-4 were tested in accordance with GB / T24346-2009 "Evaluation of Anti-mildew Properties of Textiles". The evaluation criteria for anti-mildew effect are shown in Table 3, and the test results are shown in Table 4.

[0084] Table 3 Evaluation Criteria for Anti-mildew Effect

[0085] Table 4. Results of mold resistance test

[0086] Test Example 3 Storage Stability Test

[0087] Storage stability tests were conducted on the finishing solutions obtained in step (2) of the preparation methods in Examples 1-4 and Comparative Examples 1-7. The finishing solutions were sealed in test tubes and placed in a test tube clamp, then left to stand at room temperature. Storage stability was assessed by observing the emulsion for stratification, precipitation, aggregation, or discoloration on days 2, 4, 7, and 30. If no stratification, precipitation, aggregation, or discoloration occurred, the emulsion was considered unchanged; otherwise, it was considered to have changed. The test results are shown in Table 5.

[0088] Table 5 Results of stability test of finishing liquid

[0089] In this invention, sodium silicate, sodium carboxymethyl cellulose, and polyvinylpyrrolidone are added to the finishing solution as thickening and stabilizing agents. The synergistic effect of these three agents is beneficial to the long-term stability of the finishing solution, making it less prone to stratification, precipitation, agglomeration, or discoloration.

[0090] Test Example 4: Duration Test

[0091] By using 28m 3 The repellent effects of Examples 1-4 and Comparative Examples 1 and 6-7 were tested in a standard glass-enclosed environment at a specified temperature of 26℃±2℃ and humidity of 60%±20% for a specified time. A glass house simulated the repellent experiment, with a tethered mouse used as bait. Fifty Aedes mosquitoes were introduced into the glass house in each experiment. The experiment was conducted from 16:00 to 8:00 under simulated darkness conditions with the lights off. The blank control group consisted of polyester fabric without finishing solution placed in a perforated, hangable plastic shell. Mosquitoes were collected the next day to observe blood-feeding and knockdown behavior. After the experiment, the substrates were stored in a climate chamber. The persistence of the samples was evaluated again at 1 month, 2 months, and 3 months. The results are shown in Table 6.

[0092] Table 6 Results of the Duration Test

[0093] As shown in Table 6, the emulsifiers in Comparative Examples 6-7 are different from those in Example 2, and their residual effect is significantly worse than that in Example 2. This indicates that the emulsifier in this invention has a significant effect on residual effect and stable release of active ingredients.

[0094] The above detailed description is a specific description of one of the feasible embodiments of the present invention. This embodiment is not intended to limit the patent scope of the present invention. All equivalent implementations or modifications that do not depart from the present invention should be included within the scope of the technical solution of the present invention.

Claims

1. A composition with mosquito-repellent effect, characterized in that, The composition consists of a polyester or nonwoven fabric coated with a finishing liquid and a frame that provides fixation. The finishing liquid contains the following raw materials: pyrethroids, cosolvents, emulsifiers, thickeners and stabilizers, binders, antioxidants, UV absorbers, and water. The thickener and stabilizer is a mixture of sodium silicate, sodium carboxymethyl cellulose, and polyvinylpyrrolidone.

2. The composition according to claim 1, characterized in that, The mass ratio of sodium silicate, sodium carboxymethyl cellulose, and polyvinylpyrrolidone is 1:3-5:3-5.

3. The composition according to claim 1, characterized in that, The finishing solution comprises, by weight percentage: 1%-40% pyrethroids, 20%-30% cosolvents, 3%-5% emulsifiers, 5%-8% thickeners and stabilizers, 5-10% binders, 1%-3% antioxidants, 1%-3% UV absorbers, and the balance being water.

4. The composition according to claim 1, characterized in that, The finishing solution also includes α-ethylidene-phenylacetaldehyde as a raw material.

5. The composition according to claim 4, characterized in that, The finishing solution comprises, by weight percentage: 1%-40% pyrethroids, 1%-40% α-ethylidene-phenylacetaldehyde, 20%-30% cosolvents, 3%-5% emulsifiers, 5%-8% thickeners and stabilizers, 5-10% binders, 1%-3% antioxidants, 1%-3% UV absorbers, and the balance being water.

6. The composition according to any one of claims 1-5, characterized in that, The pyrethroid is selected from one or more of tetrafluoroethylene, tetrafluorobenzyl, heptafluoromethrin, tetrafluoromethrin, methoxyfenozide, and dextromethorphan; the cosolvent is selected from any one of ethylene glycol, ethyl acetate, ethyl formate, and dipropylene glycol dimethyl ether.

7. The composition according to any one of claims 1-5, characterized in that, The emulsifier is a mixture of polyoxyethylene hydrogenated castor oil and sodium dodecyl sulfate, wherein the mass ratio of the polyoxyethylene hydrogenated castor oil to sodium dodecyl sulfate is 1:1-3.

8. The composition according to any one of claims 1-5, characterized in that, The adhesive is JB-30 acrylic emulsion; the ultraviolet absorber is selected from one or more of ultraviolet absorbers UV-0, UV-531, and UV-9.

9. The composition according to any one of claims 1-5, characterized in that, The antioxidant is a mixture of propyl gallate and 2,6-di-tert-butyl-p-cresol, wherein the mass ratio of propyl gallate to 2,6-di-tert-butyl-p-cresol is 1:3-4.

10. A method for preparing the composition according to any one of claims 4-9, characterized in that, Includes the following steps: (1) Mix the cosolvent with pyrethroid and α-ethylidene-phenylacetaldehyde, add emulsifier, stir, and obtain mixture 1; (2) Mix mixture 1, adhesive, antioxidant, ultraviolet absorber, thickening stabilizer and water to obtain finishing solution; (3) Immerse the polyester fabric in the finishing solution, then pass it through the pressure roller, dry it, and cut it to obtain the polyester fabric coated with the finishing solution. (4) Place the polyester or non-woven fabric coated with the finishing liquid into the frame that serves to fix it, and fasten it to obtain the composition.

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