Washing machine tank cleaning effervescent tablet and preparation method thereof

Abstract

The invention relates to the technical field of daily chemical industry, in particular to a washing machine tank cleaning effervescent tablet and a preparation method thereof. The washing machine tank cleaning effervescent tablet is prepared from the following raw materials in parts by weight: 40 to 60 parts of sodium percarbonate, 4 to 6 parts of tetraacetylethylenediamine, 1 to 3 parts of tetraacetyl glycoluril, 3 to 5 parts of microencapsulated sodium silicate, 12 to 18 parts of microencapsulated citric acid, 0.5 to 1.5 parts of benzotriazole, 0.5 to 1.5 parts of hydroxybenzotriazole, 1 to 2 parts of composite antibacterial agent, 3 to 5 parts of polyvinylpolypyrrolidone and 1 to 2 parts of magnesium stearate. And 0.3 to 0.7 part of essence. The washing machine tank cleaning effervescent tablet is prepared through gradient temperature control mixing and layered tabletting technologies, and has the effects of efficient cleaning, rapid disintegration, efficient antibiosis, small dosage and effective prevention of corrosion of metal parts in a low-temperature environment.

Description

Technical Field

[0001] The invention relates to the technical field of daily chemical products, in particular to a washing machine tank cleaning effervescent tablet and a preparation method thereof. Background Art

[0002] Washing machines are the primary source of daily laundry cleaning in households. Over time, as wash water flows between the washing machine's tub and inner drum, impurities such as scale, loose detergent particles, clothing fibers, and human organic matter adhere to the inner tub walls. These impurities ferment at room temperature, forming a layer of dark, sticky stains and stubborn dirt. These stains also breed numerous pathogens, which can be transmitted to the next load of clothing during the wash cycle, causing "secondary contamination" of clothing. These cross-infection bacteria can easily lead to various skin and gynecological diseases, endangering human health. Therefore, washing machine tub cleaners not only thoroughly remove stubborn dirt and stains from the anti-anionic surfactants accumulated in the washing machine's inner tank and interlayer tub due to long-term use, but also have the crucial function of quickly removing microorganisms to prevent secondary contamination.

[0003] Currently, there are many types of washing machine trough cleaners on the market, with granular solid cleaners and effervescent tablets dominating the market. These two types of washing machine trough cleaners primarily consist of sodium percarbonate and other additives. Their primary function is to remove residual anti-anionic surfactants, dirt, mold, and odors from the inner tank and interlayer of the washing machine. Currently available solid trough cleaners dissolve slowly and require elevated temperatures to work, wasting energy. They are also typically packaged in bags of 200 to 300 grams, making maintenance and cleaning wasteful. The alkalinity in these cleaners is too strong, easily corroding the inner walls of the machine, while too weak an alkalinity is ineffective in removing scale buildup in the washing machine trough.

[0004] In view of the above-mentioned related technologies, this field urgently needs to develop a washing machine tank cleaning effervescent tablet that can clean at low temperature, disintegrate quickly, use small amounts, and effectively clean dirt and antibacterial in the washing machine tank, while preventing strong alkali from corroding the inner drum and parts of the washing machine. Summary of the Invention

[0005] In order to meet the requirements of washing machine trough cleaning effervescent tablets for efficient cleaning, rapid disintegration, high antibacterial properties, small dosage, and effective prevention of corrosion of metal parts in a low temperature environment, the present application provides a washing machine trough cleaning effervescent tablet and a preparation method thereof.

[0006] In a first aspect, the present application provides a washing machine tank cleaning effervescent tablet, which adopts the following technical solution: A washing machine trough cleaning effervescent tablet is prepared from the following raw materials in parts by weight: 40-60 parts of sodium percarbonate, 4-6 parts of tetraacetylethylenediamine, 1-3 parts of tetraacetylglycoluril, 3-5 parts of microencapsulated sodium silicate, 12-18 parts of microencapsulated citric acid, 0.5-1.5 parts of benzotriazole, 0.5-1.5 parts of hydroxybenzotriazole, 1-2 parts of a composite antibacterial agent, 3-5 parts of cross-linked polyvinylpyrrolidone, 1-2 parts of magnesium stearate, and 0.3-0.7 parts of flavor.

[0007] By adopting the above solution, sodium percarbonate, tetraacetylethylenediamine, and tetraacetylglycoluril are compounded to ensure dissolution speed and provide strong oxidizing properties, effectively removing dirt from the washing machine tub and quickly sterilizing. At the same time, the decomposition products of TAED and TAGU are acetic acid, which is environmentally friendly. Microencapsulated sodium silicate and microencapsulated citric acid are coated using microencapsulation technology to avoid premature reaction. After release, they can adjust the pH value of the detergent, maintaining acid-base balance during the washing process and protecting the washing machine drum and parts. Benzotriazole and hydroxybenzotriazole corrosion inhibitors enhance the corrosion inhibition effect while maintaining the stability of the detergent, preventing strong alkali corrosion of the washing machine drum and parts, and extending the service life of the washing machine. Cross-linked polyvinylpyrrolidone, as a surfactant and disintegrant, not only enhances the detergent's decontamination ability and improves the washing effect, but also accelerates the disintegration of the effervescent tablet in water, reducing the dosage.

[0008] Preferably, the washing machine trough cleaning effervescent tablet is made from the following raw materials in parts by weight: 53 parts of sodium percarbonate, 4.6 parts of tetraacetylethylenediamine, 2.1 parts of tetraacetylglycoluril, 5 parts of microencapsulated sodium silicate, 14 parts of microencapsulated citric acid, 1 part of benzotriazole, 0.8 part of hydroxybenzotriazole, 1.3 parts of composite antibacterial agent, 4.2 parts of cross-linked polyvinylpyrrolidone, 1.5 parts of magnesium stearate, and 0.5 part of flavor.

[0009] Preferably, the composite antibacterial agent is benzalkonium chloride and the composite enzyme in a mass ratio of 1:(0.5-1).

[0010] By adopting the above scheme, the composite enzyme in the composite antibacterial agent can improve the biofilm removal rate at a low temperature of 10-25°C by enzymatically hydrolyzing the protein, fat and polysaccharide components in the biofilm. The composite enzyme and benzalkonium chloride exhibit significant synergistic effects and enhanced antibacterial function.

[0011] Preferably, the complex enzyme is three or more of lipase, protease, cellulase, amylase, hemicellulase, catalase, and lysozyme.

[0012] Preferably, the preparation of the microencapsulated citric acid comprises the following steps: dry mixing citric acid and magnesium stearate in a mixer for 10 minutes, slowly spraying a 3% hydroxypropyl methylcellulose solution at a flow rate of 5 mL / min for ≥20 minutes, mixing until particles are formed, moving to an oven at 40-45° C. and drying for 2 hours, and passing through a 30-mesh sieve.

[0013] By adopting the above scheme and microencapsulating citric acid, it is possible to avoid premature gas generation caused by direct contact between sodium percarbonate and citric acid in a dry environment, which would lead to the failure of the effervescent tablet.

[0014] Preferably, in the preparation scheme of the microencapsulated citric acid, the mass ratio of citric acid to magnesium stearate to 3% hydroxypropyl methylcellulose solution is (15-17):(2-4):1.

[0015] Preferably, in the preparation scheme of the microencapsulated citric acid, the mass ratio of citric acid to magnesium stearate to 3% hydroxypropyl methylcellulose solution is 16:3:1.

[0016] Preferably, in the preparation scheme of the microencapsulated citric acid, the coating thickness is 5-10 μm.

[0017] Preferably, the microencapsulated sodium silicate is prepared by the following technical scheme: heating hydrogenated vegetable oil to 60-65° C. to melt, slowly adding sodium silicate powder to the molten hydrogenated vegetable oil and stirring evenly, then adding talcum powder and stirring until evenly dispersed, pouring into a cold plate and rapidly cooling and solidifying, and then crushing and passing through a 20-40 mesh sieve to obtain a particle size of 0.5-2 mm.

[0018] By adopting the above scheme, sodium silicate is easy to absorb moisture and agglomerate, and the storage stability of sodium silicate is improved after microencapsulation and embedding, while avoiding direct contact with acidic components such as microencapsulated citric acid to produce gas, ensuring the rapid release of alkaline environment after the effervescent tablet disintegrates, thereby enhancing the corrosion inhibition and decontamination effects.

[0019] Preferably, during the preparation of the microencapsulated sodium silicate, the particle size of the sodium silicate powder is 80-120 μm.

[0020] Preferably, during the preparation of the microencapsulated sodium silicate, the mass ratio of sodium silicate powder to hydrogenated plant to talc is (11-15):(5-7):1.

[0021] Preferably, during the preparation of the microencapsulated sodium silicate, the mass ratio of sodium silicate powder to hydrogenated plant matter to talc is 13:6:1.

[0022] In the second aspect, the present application provides a method for preparing effervescent tablets for cleaning washing machine troughs, adopting the following technical solution: S1 alkaline layer mixing: sodium percarbonate, tetraacetylethylenediamine, tetraacetyl glycoluril, microencapsulated sodium silicate and a composite antibacterial agent are mixed at a speed of 15-20 rpm and a low temperature of 10-15°C for 8-15 minutes to obtain an alkaline layer mixture.

[0023] S2 acid layer mixing: benzotriazole, hydroxybenzotriazole, microencapsulated citric acid, cross-linked polyvinylpyrrolidone, magnesium stearate and flavor are mixed at a low speed of 8-10 rpm for 5-10 minutes, with the material temperature ≤30°C, to obtain an acid layer mixture.

[0024] S3 layered tableting: Use a layered rotary tablet press, add the acid layer mixture prepared in S2 into hopper A, add the base layer mixture prepared in S1 into hopper B, the pre-pressure of hopper A is 5-10kN, the final pressure of hopper B is 25-30kN, spray 0.5% HPMC ethanol solution at the acid / base interface, 0.5-1mL / m 2 , atomized particle size 10-15μm, coverage ≥95%, interface pressure 15kN, maintained for 1s; obtain washing machine tank cleaning effervescent tablets.

[0025] By adopting the above scheme, gradient temperature-controlled mixing solves the thermal sensitivity contradiction between sodium percarbonate and enzyme preparations. The material temperature is ≤30℃ to prevent excessive mixing and stratification, thereby improving the compatibility of the effective ingredients of the low-temperature cleaning agent; layered tableting isolates the acidic and alkaline components to prevent premature reaction and maintain their respective activity.

[0026] Preferably, the 0.5% HPMC ethanol solution is prepared by the following scheme: 5 parts of HPMC are slowly added to 495 parts of ethanol, the ethanol solution temperature is less than 10°C, and the speed is 300-500 rpm. The solution is transferred to a 40-50°C water bath, 500 parts of deionized water preheated to 40°C are gradually added, and stirred at 800-1000 rpm for 30 minutes. Then, the solution is passed through a high-pressure homogenizer at a pressure of 20-50 MPa and cycled 2-3 times to ensure that no particles remain.

[0027] In summary, this application has the following beneficial effects: 1. The present application prepares a washing machine tank cleaning effervescent tablet, which has the effects of efficient cleaning, rapid disintegration, high antibacterial effect in a low temperature environment, and small dosage, and can effectively prevent metal parts from being corroded.

[0028] 2. This washing machine tub cleaning effervescent tablet utilizes a combination of sodium percarbonate, tetraacetylethylenediamine, and tetraacetylglycoluril to ensure rapid dissolution and provide strong oxidizing properties, effectively removing dirt from the washing machine tub and rapidly sterilizing. TAED and TAGU decompose into acetic acid, making it environmentally friendly. Microencapsulated sodium silicate and microencapsulated citric acid, using microencapsulation coating technology, prevent premature reaction. After release, they can adjust the pH of the cleaning agent, maintaining acid-base balance during the wash process and protecting the washing machine drum and parts.

[0029] 3. The washing machine tub cleaning effervescent tablets of the present application use a composite corrosion inhibitor composed of benzotriazole and hydroxybenzotriazole to enhance the corrosion inhibition effect while maintaining the stability of the cleaning agent, thereby preventing the inner drum and parts of the washing machine from being corroded by strong alkali and extending the service life of the washing machine.

[0030] 4. The washing machine trough cleaning effervescent tablets of the present application use a composite antibacterial agent, and the combination of composite enzyme and benzalkonium chloride shows a significant synergistic effect and antibacterial function enhancement effect; the combination of composite enzymes decomposes the protein, fat and polysaccharide components in the biofilm through enzymes, and effectively improves the biofilm removal rate at a low temperature of 10-25°C.

[0031] 5. The preparation method of the washing machine trough cleaning effervescent tablets of the present application solves the thermal sensitivity conflict between sodium percarbonate and enzyme preparations through gradient temperature-controlled mixing. The material temperature is ≤30°C to prevent excessive mixing and stratification, thereby improving the compatibility of the effective ingredients of the low-temperature cleaning agent; layered tableting isolates the acidic and alkaline components to prevent premature reaction and maintain their respective activity. DETAILED DESCRIPTION

[0032] The technical solution of the present application is further illustrated below through specific embodiments. The specific embodiments do not limit the scope of protection of the present application; some non-essential modifications and adjustments made by others based on the concept of the present application still fall within the scope of protection of the present application.

[0033] Unless otherwise specified, the experimental methods described in the following examples are conventional methods. The reagents, enzyme preparations, and materials described are all commercially available products.

[0034] Choice of washing machine: A household fully automatic pulsator washing machine with a capacity of 8kg, which has been used for more than 4 years and has never been cleaned in any way.

[0035] The present application is further described in detail below with reference to the following examples and comparative examples.

[0036] Preparation Example Preparation Example 1-14 Preparation of composite antibacterial agent The composite antibacterial agent is benzalkonium chloride and composite enzyme in a mass ratio of 1:(0.5-1).

[0037] The complex enzyme is three or more of lipase, protease, cellulase, amylase, hemicellulase, catalase and lysozyme.

[0038] The composite antibacterial agent was prepared by compounding in different ratios. The compounding ratios and the masses of each component are shown in Table 1.

[0039] Table 1 Ratio and mass (kg) of each component of the composite antibacterial preparation examples 1-14 Preparation Example 15 Preparation of Microencapsulated Citric Acid The preparation of microencapsulated citric acid comprises the following steps: dry mixing 15 kg of citric acid and 2 kg of magnesium stearate in a mixer for 10 minutes, slowly spraying 1 kg of 3% hydroxypropyl methylcellulose solution at a flow rate of 5 mL / min for 20 minutes or longer, mixing until particles are formed with a coating thickness of 5-10 μm, drying in an oven at 40-45° C. for 2 hours, and filtering through a 30-mesh sieve.

[0040] Among them, 3% hypromellose solution, weigh 30g of hypromellose, add 970g of deionized water step by step, mix and stir until swelling is complete, and obtain a transparent solution.

[0041] Preparation Example 16 Preparation of Microencapsulated Citric Acid The preparation of microencapsulated citric acid comprises the following steps: dry mixing 17 kg of citric acid and 4 kg of magnesium stearate in a mixer for 10 minutes, slowly spraying 1 kg of 3% hydroxypropyl methylcellulose solution at a flow rate of 5 mL / min for 20 minutes or longer, mixing until particles are formed with a coating thickness of 5-10 μm, drying in an oven at 40° C. for 2 hours, and filtering through a 30-mesh sieve.

[0042] Among them, 3% hypromellose solution, weigh 30g of hypromellose, add 970g of deionized water step by step, mix and stir until swelling is complete, and obtain a transparent solution.

[0043] Preparation Example 17 Preparation of Microencapsulated Citric Acid The preparation of microencapsulated citric acid comprises the following steps: dry-mixing 16 kg of citric acid and 3 kg of magnesium stearate in a mixer for 10 minutes, slowly spraying 1 kg of 3% hydroxypropyl methylcellulose solution at a flow rate of 5 mL / min for 20 minutes or longer, mixing until particles are formed with a coating thickness of 5-10 μm, drying in an oven at 40-45° C. for 2 hours, and filtering through a 30-mesh sieve.

[0044] Among them, 3% hypromellose solution, weigh 30g of hypromellose, add 970g of deionized water step by step, mix and stir until swelling is complete, and obtain a transparent solution.

[0045] Preparation Example 18 Preparation of Microencapsulated Sodium Silicate The preparation of microencapsulated sodium silicate includes the following steps: heating 5 kg of hydrogenated vegetable oil to 60-65° C. to melt, slowly adding 11 kg of sodium silicate powder into the molten hydrogenated vegetable oil and stirring evenly, then adding 1 kg of talcum powder and stirring until evenly dispersed, pouring into a cold plate and rapidly cooling and solidifying, and then crushing and passing through a 20-40 mesh sieve to obtain a particle size of 0.5-2 mm.

[0046] Preparation Example 19 Preparation of Microencapsulated Sodium Silicate The preparation of microencapsulated sodium silicate includes the following steps: heating 7 kg of hydrogenated vegetable oil to 60-65° C. to melt, slowly adding 15 kg of sodium silicate powder into the molten hydrogenated vegetable oil and stirring evenly, then adding 1 kg of talcum powder and stirring until evenly dispersed, pouring into a cold plate and rapidly cooling and solidifying, crushing and passing through a 20-40 mesh sieve, and obtaining a particle size of 0.5-2 mm.

[0047] Preparation Example 20 Preparation of Microencapsulated Sodium Silicate The preparation of microencapsulated sodium silicate includes the following steps: heating 6 kg of hydrogenated vegetable oil to 60-65° C. to melt, slowly adding 13 kg of sodium silicate powder into the molten hydrogenated vegetable oil and stirring evenly, then adding 1 kg of talcum powder and stirring until evenly dispersed, pouring into a cold plate and rapidly cooling and solidifying, crushing and passing through a 20-40 mesh sieve, and obtaining a particle size of 0.5-2 mm.

[0048] Preparation Example 21 Preparation of 0.5% HPMC ethanol solution A 0.5% HPMC ethanol solution was prepared as follows: 5 g of HPMC was slowly added to 495 g of ethanol at a temperature of <10°C and stirred at 300-500 rpm. The solution was transferred to a 40-50°C water bath, and 500 g of deionized water preheated to 40°C was gradually added. The solution was stirred at 800-1000 rpm for 30 minutes. The solution was then passed through a high-pressure homogenizer at a pressure of 20-50 MPa for 2-3 cycles to ensure that no particles remained. Example

[0049] Example 1 A washing machine tank cleaning effervescent tablet, the preparation method of which is as follows: S1 Alkaline layer mixing: 53 kg of sodium carbonate, 4.6 kg of tetraacetylethylenediamine, 2.1 kg of tetraacetylglycoluril, 5 kg of microencapsulated sodium silicate and 1.3 kg of composite antibacterial agent were mixed at a speed of 15 rpm and a low temperature of 10-15° C. for 10 minutes to obtain an alkaline layer mixture.

[0050] S2 acid layer mixing: 1 kg of benzotriazole, 0.8 kg of hydroxybenzotriazole, 14 kg of microencapsulated citric acid, 4.2 kg of cross-linked polyvinylpyrrolidone, 1.5 kg of magnesium stearate and 0.5 kg of flavor were mixed at a low speed of 10 rpm for 10 minutes with the material temperature ≤ 30°C to obtain an acid layer mixture.

[0051] S3 layered tableting: Use a layered rotary tablet press, add the acid layer mixture prepared in S2 into hopper A, add the base layer mixture prepared in S1 into hopper B, the pre-pressure of hopper A is 7kN, the final pressure of hopper B is 28kN, spray a 0.5% HPMC ethanol solution between the acid layer and the base layer at a dosage of 0.7mL / m 2 , atomized particle size 10-15μm, coverage ≥95%, interface pressure 15kN, maintained for 1s; obtain washing machine tank cleaning effervescent tablets.

[0052] Example 2 A washing machine tank cleaning effervescent tablet, the preparation method of which is as follows: S1 Alkaline layer mixing: 40 kg of sodium carbonate, 4 kg of tetraacetylethylenediamine, 3 kg of tetraacetylglycoluril, 3 kg of microencapsulated sodium silicate and 2 kg of composite antibacterial agent were mixed at a speed of 10 rpm and a low temperature of 10-15° C. for 8 minutes to obtain an alkaline layer mixture.

[0053] S2 acid layer mixing: 0.5 kg of benzotriazole, 0.5 kg of hydroxybenzotriazole, 12 kg of microencapsulated citric acid, 3 kg of cross-linked polyvinylpyrrolidone, 1 kg of magnesium stearate and 0.3 kg of flavor were mixed at a low speed of 10 rpm for 5 minutes with the material temperature ≤ 30° C. to obtain an acid layer mixture.

[0054] S3 layered tableting: Use a layered rotary tablet press, add the acid layer mixture prepared in S2 into hopper A, add the base layer mixture prepared in S1 into hopper B, the pre-pressure of hopper A is 5kN, the final pressure of hopper B is 25kN, spray a 0.5% HPMC ethanol solution between the acid layer and the base layer at a dosage of 0.5mL / m 2 , atomized particle size 10-15μm, coverage ≥95%, interface pressure 15kN, maintained for 1s; obtain washing machine tank cleaning effervescent tablets.

[0055] Example 3 A washing machine tank cleaning effervescent tablet, the preparation method of which is as follows: S1 Alkaline layer mixing: 60 kg of sodium carbonate, 6 kg of tetraacetylethylenediamine, 3 kg of tetraacetylglycoluril, 5 kg of microencapsulated sodium silicate and 2 kg of composite antibacterial agent were mixed at a speed of 20 rpm and a low temperature of 10-15° C. for 15 minutes to obtain an alkaline layer mixture.

[0056] S2 acid layer mixing: 1.5 kg of benzotriazole, 1.5 kg of hydroxybenzotriazole, 18 kg of microencapsulated citric acid, 5 kg of cross-linked polyvinylpyrrolidone, 2 kg of magnesium stearate and 0.7 kg of flavor were mixed at a low speed of 8 rpm for 10 minutes with the material temperature ≤ 30°C to obtain an acid layer mixture.

[0057] S3 layered tableting: Select a layered rotary tablet press, add the acid layer mixture prepared in S2 into hopper A, add the base layer mixture prepared in S1 into hopper B, the pre-pressure of hopper A is 10kN, the final pressure of hopper B is 30kN, spray a 0.5% HPMC ethanol solution between the acid layer and the base layer at a dosage of 1mL / m 2 , atomized particle size 10-15μm, coverage ≥95%, interface pressure 15kN, maintained for 1s; obtain washing machine tank cleaning effervescent tablets.

[0058] Comparative Example Comparative Example 1 The same as Example 3, except that the microencapsulated citric acid is the microencapsulated citric acid prepared in Preparation Example 15.

[0059] Comparative Example 2 The same as Example 3, except that the microencapsulated citric acid is the microencapsulated citric acid prepared in Preparation Example 16.

[0060] Comparative Example 3 The same as Example 3, except that the microencapsulated citric acid is the microencapsulated citric acid prepared in Preparation Example 17.

[0061] Comparative Example 4 The same as Example 3, except that the microencapsulated sodium silicate is the microencapsulated sodium silicate prepared in Preparation Example 18.

[0062] Comparative Example 5 The same as Example 3, except that the microencapsulated sodium silicate is the microencapsulated sodium silicate prepared in Preparation Example 19.

[0063] Comparative Example 6 The same as Example 3, except that the microencapsulated sodium silicate is the microencapsulated sodium silicate prepared in Preparation Example 20.

[0064] Comparative Examples 7-13 The same as Example 3, except that the components and addition amounts of the washing machine tank cleaning effervescent tablets are as shown in Table 2.

[0065] Table 2 Components and addition amounts (kg) of the washing machine tank cleaning effervescent tablets of Comparative Examples 7-13 Note: “ / ” means that the component is not added.

[0066] Performance testing 1. Determination of sterilization rate and test results: According to the test steps 2.1.1.2.3, 2.1.1.5.5 and 2.1.1.7.3 of the Technical Specifications for Disinfection (2002 edition), bacterial solution was prepared, neutralizing agent was identified and sterilization rate was determined.

[0067] (1) Preparation of bacterial suspension: 18 h fresh slant cultures of Staphylococcus aureus (ATCC6538), Escherichia coli (8099), and Candida albicans (ATCC10231) were taken, the bacterial moss was washed with tryptone saline solution (TPS) and diluted to a certain concentration of bacterial suspension, and an equal amount of bovine serum albumin (BSA) was added to prepare the experimental bacterial suspension.

[0068] (2) Neutralizer identification test The test bacteria were Staphylococcus aureus, Escherichia coli and Candida albicans. The neutralizer identification test was carried out using the suspension method. The test results showed that Group 1 had no bacteria or only very few colonies grew, Group 2 had colony growth, which was more than Group 1, but less than Groups 3, 4 and 5. The error rate of colony counts among Groups 3, 4 and 5 did not exceed 15%, and Group 6 had no sterile growth, indicating that the selected neutralizer was appropriate.

[0069] (3) Suspension method quantitative sterilization test: Use sterile hard water to prepare the washing machine trough cleaning agent to 1.25 times the use concentration, take 4 mL and add it to a sterile test tube, place it in a 20℃ water bath for 5 minutes, add 1 mL of the test bacterial suspension, mix it immediately and time it. After the specified time, take out 0.5 mL and add it to a 4.5 mL neutralizer test tube, mix and dilute it, and select the appropriate dilution to inoculate it into the plate. TPS is used instead of disinfectant in the positive control group. The rest of the steps are the same as the experimental group. After the test, all plates are placed in a 37℃ incubator and incubated for the specified time to record the results.

[0070] (4) Quantitative sterilization test of bacterial suspension. According to the instructions for use of each cleaning agent, prepare a washing machine trough cleaning effervescent tablet cleaning sample solution of corresponding concentration with sterile hard water (the concentration of the sample solution is required to be 1.25 times the concentration to be tested), and keep it in a constant temperature (20℃±1℃) water bath for use. Add 1mL of the test bacterial suspension to a sterile test tube, shake well, keep it in a constant temperature (20℃±1℃) water bath for 5 minutes, then add 4.0mL of the washing machine trough cleaning effervescent tablet cleaning sample solution of the above concentration, shake well, and time it. After the bacterial suspension and the washing machine trough cleaning effervescent tablet cleaning sample solution react for the predetermined time, take 0.5mL of the test bacterial suspension-washing machine trough cleaning effervescent tablet cleaning sample solution mixture in a test tube and add it to 4.5mL of the neutralizer and mix well. After the test bacteria-washing machine trough cleaning effervescent tablet cleaning sample in each test tube interacted with the neutralizer for 10 minutes, 1.0 mL of sample solution was respectively aspirated and two culture dishes were inoculated with each tube of sample solution to determine the number of surviving bacteria. The test was repeated three times. At the same time, the diluent was used instead of the washing machine trough cleaning effervescent tablet cleaning sample solution to perform a positive parallel control test.

[0071] By preparing the proportions of the composite antibacterial agents of Examples 1-14, experiments were conducted on the basis of Example 1 to obtain the determination results of the sterilization rate, as shown in Tables 3-5.

[0072] Table 3 Escherichia coli sterilization rate test results of Preparation Examples 1-14 Table 4 Test results of the sterilization rate of Staphylococcus aureus in Preparation Examples 1-14 Table 5 Candida albicans sterilization rate test results of Preparation Examples 1-14 As can be seen from the test result of Table 3-5, by the ratio of the composite antimicrobial agent provided by Preparation Example 1-14, tested on the basis of Example 1, the longer the washing machine tank cleaning effervescent tablet and the test bacteria action time of preparation, the higher the sterilization rate for Staphylococcus aureus (ATCC6538), Escherichia coli (8099) and Candida albicans (ATCC10231), sterilization rate is positively correlated with action time, but after acting on 45min, sterilization rate tends to be stable, and sterilization rate is 99.999%, no longer growing with the increase of action time. Illustrate that composite antimicrobial agent, at low temperatures, is compounded by complex enzyme and benzalkonium chloride and shows significant synergistic effect and antimicrobial function strengthening effect; It is decomposed into hydrogen peroxide in water in conjunction with sodium percarbonate, by destroying bacterial cell wall, cellular enzyme, amino acid, protein and DNA, the active ingredient content in the washing machine tank cleaning effervescent tablet of preparation is higher, can fully act with microorganism, effectively sterilize.

[0073] 2. Determination and test results of active oxygen content and stability: The active oxygen content test refers to the "Hygienic Requirements for Sodium Percarbonate Disinfectants" (WT / T 6456-2019), and the active oxygen content of each washing machine trough cleaning effervescent tablet is determined by redox titration and compared. Accurately weigh 5g of sample, soak it with a small amount of distilled water and 25mL of sulfuric acid to fully dissolve the sample, then transfer it to a 500mL volumetric flask, adjust the volume, and shake well. Use a pipette to accurately transfer 20mL of test solution into a conical flask, and titrate with 0.1mol / L potassium permanganate standard solution until the solution turns light pink and does not fade within 30s. At the same time, perform a corresponding blank control test.

[0074] Stability testing: Accelerated testing was used to determine the stability of various washing machine effervescent tablets. Accurately weigh 50.0g of sample, place it in a test tube, stopper it, and place it on a test tube rack in an electric constant-temperature drying oven. After storing at 50°C for 14 days, remove it, cool it, invert it in a beaker, and shake it well. Calculate the rate of decrease in active oxygen content according to the active oxygen content determination method.

[0075] The test results are shown in Table 6 below: Table 6 Determination of active oxygen content and stability of washing machine tank cleaning effervescent tablets The test results for the active oxygen content and stability of the washing machine trough cleaning effervescent tablets prepared by Examples 1-3 and Comparative Examples 1-6 are shown in Table 6. The active oxygen content of the washing machine trough cleaning effervescent tablets prepared by Examples 1-3 and Comparative Examples 1-6 ranged from 12.81% to 13.96%, and after storage at 50°C for 14 days, the active oxygen content decreased by 3.51% to 6.96%, indicating that the washing machine trough cleaning effervescent tablets prepared by Examples 1-3 and Comparative Examples 1-6 had strong stability. However, the active oxygen content of Comparative Examples 7-13 ranged from 10.72% to 12.0%, and after storage at 50°C for 14 days, the active oxygen content decreased by 18.20% to 43.15%, indicating lower active oxygen content and poorer stability. It can be inferred that the effervescent tablets had poor storage stability under accelerated test conditions. This may be due to the neutralization reaction between the effervescent acid in the effervescent tablet and the base in the sodium percarbonate at 50°C, resulting in decomposition of the active ingredient hydrogen peroxide, which caused product instability.

[0076] The washing machine tank cleaning effervescent tablets prepared in Examples 1-3 and Comparative Examples 1-6 are compounded with sodium percarbonate, tetraacetylethylenediamine, and tetraacetylglycoluril to ensure dissolution speed, provide strong oxidizing properties, effectively remove dirt from the washing machine tank and quickly sterilize. At the same time, the decomposition products of tetraacetylethylenediamine and tetraacetylglycoluril are acetic acid, which is environmentally friendly.

[0077] 3. Determination of corrosion rate and test results: Conduct the test in accordance with Section 3.4 of the 2008 Technical Specifications for Disinfection, which covers the determination of metal corrosion by disinfectants. First, clean the cut washing machine tub pieces with a brush. Then, soak the metal pieces in a prepared washing machine tub cleaning effervescent tablet for 10 minutes to thoroughly degrease and rinse. Degrease again with anhydrous ethanol. Dry in a 50°C constant temperature oven for 1 hour and weigh. Measure and calculate the surface area of the test tub pieces. Place the tub pieces in a 50°C constant temperature solution, rinse with clean water, and dry in a 50°C constant temperature oven for 1 hour and weigh. Test results are expressed as the average value of the metal corrosion rate (R, a corrosivity rating).

[0078] Table 7 Corrosion classification index Corrosion rate R (mg / h) level ＜0.0100 Basically no corrosion 0.0100-＜0.100 Mild corrosion 0.100-＜1.00 Moderate corrosion ≥1.00 Severe corrosion Corrosion rate test results: as shown in Table 8.

[0079] Table 8 Corrosion test results of stainless steel, copper and aluminum As shown in Table 8, the washing machine tank cleaning effervescent tablets prepared by Examples 1-3 and Comparative Examples 1-6 are essentially non-corrosive to stainless steel, copper, and aluminum. Comparative Examples 1-10 slightly corrode the metals, and Comparative Examples 11-13 slightly corrode stainless steel, copper, and aluminum. This indicates that the compounding of benzotriazole and hydroxybenzotriazole can effectively prevent the corrosion of the inner tank of the washing machine by active oxygen. Benzotriazole itself is an effective copper corrosion inhibitor, but its effect is limited when used alone, and it has toxicity issues. Hydroxybenzotriazole, due to the introduction of a hydroxyl group, can enhance its water solubility and adsorption capacity. Hydroxybenzotriazole is compounded with benzotriazole to form a more stable complex that forms a protective film on the metal surface. Microencapsulated sodium silicate and microencapsulated citric acid use microencapsulation coating technology to avoid premature reaction. After release, the pH value of the cleaning agent can be adjusted, maintaining acid-base balance during the washing process, and protecting the inner drum and parts of the washing machine.

[0080] From the above test results, it can be seen that the present application prepares washing machine trough cleaning effervescent tablets, which have the effects of efficient cleaning, rapid disintegration, high efficiency antibacterial properties, and small dosage in a low-temperature environment, and can effectively prevent metal parts from being corroded. In the preparation process, the thermal sensitivity contradiction between sodium percarbonate and enzyme preparations is solved by gradient temperature control mixing. The material temperature is ≤30°C to prevent excessive mixing and stratification, thereby improving the compatibility of the effective ingredients of the low-temperature detergent; the layered tableting isolates the acidic and alkaline components to prevent premature reaction and maintain their respective activity. By upgrading the technical formula of the washing machine trough cleaning effervescent tablets, it has won the market in terms of decontamination, antibacterial, environmental protection, and high efficiency, effectively maintaining the parts of the washing machine and prolonging the service life. It is also gentle, safe, non-toxic and odorless, protecting the health of consumers.

[0081] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as such modifications are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A washing machine tank cleaning effervescent tablet, characterized in that: The invention comprises the following raw materials in parts by weight: 40-60 parts of sodium percarbonate, 4-6 parts of tetraacetylethylenediamine, 1-3 parts of tetraacetylglycoluril, 3-5 parts of microencapsulated sodium silicate, 12-18 parts of microencapsulated citric acid, 0.5-1.5 parts of benzotriazole, 0.5-1.5 parts of hydroxybenzotriazole, 1-2 parts of composite antibacterial agent, 3-5 parts of cross-linked polyvinylpyrrolidone, 1-2 parts of magnesium stearate and 0.3-0.7 parts of essence.

2. The washing machine tank cleaning effervescent tablet according to claim 1, characterized in that: The composite antibacterial agent is benzalkonium chloride and composite enzyme in a mass ratio of 1:(0.5-1).

3. The washing machine tank cleaning effervescent tablet according to claim 1, characterized in that: The complex enzyme is three or more of lipase, protease, cellulase, amylase, hemicellulase, catalase and lysozyme.

4. The washing machine tank cleaning effervescent tablet according to claim 1, characterized in that: The preparation of the microencapsulated citric acid comprises the following steps: dry-mixing citric acid and magnesium stearate in a mixer for 10 minutes, slowly spraying a 3% hydroxypropyl methylcellulose solution at a flow rate of 5 mL / min for 20 minutes or longer, mixing until particles are formed, drying in an oven at 40-45° C. for 2 hours, and filtering through a 30-mesh sieve.

5. The washing machine tank cleaning effervescent tablet according to claim 1, characterized in that: In the preparation of the microencapsulated citric acid, the mass ratio of citric acid to magnesium stearate to 3% hydroxypropyl methylcellulose solution is (15-17):(2-4):

1.

6. The washing machine tank cleaning effervescent tablet according to claim 1, characterized in that: In the preparation of the microencapsulated citric acid, the coating thickness is 5-10 μm.

7. The washing machine tank cleaning effervescent tablet according to claim 1, characterized in that: The preparation of the microencapsulated sodium silicate comprises the following steps: heating hydrogenated vegetable oil to 60-65° C. and melting it; slowly adding sodium silicate powder into the molten hydrogenated vegetable oil and stirring it evenly; then adding talcum powder and stirring it until it is evenly dispersed; pouring it into a cold plate and rapidly cooling and solidifying it; and then crushing it through a 20-40 mesh sieve to obtain a particle size of 0.5-2 mm.

8. The washing machine tank cleaning effervescent tablet according to claim 1, characterized in that: In the preparation of the microencapsulated sodium silicate, the mass ratio of sodium silicate powder to hydrogenated plant matter to talc is (11-15):(5-7):

1.

9. A method for preparing a washing machine tank cleaning effervescent tablet according to any one of claims 1 to 8, characterized in that: It includes the following steps: S1 Alkaline layer mixing: Sodium percarbonate, tetraacetylethylenediamine, tetraacetyl glycoluril, microencapsulated sodium silicate and composite antibacterial agent are mixed at a speed of 15-20 rpm and 10-15° C. for 8-15 minutes to obtain an alkaline layer mixture; S2 Acid layer mixing: Benzotriazole, hydroxybenzotriazole, microencapsulated citric acid, cross-linked polyvinylpyrrolidone, magnesium stearate and flavor are mixed at a low speed of 8-10 rpm for 5-10 minutes, with the material temperature ≤30°C, to obtain an acid layer mixture; S3 layered tableting: Use a laminated rotary tablet press, add the acid layer mixture prepared in S2 into hopper A, and add the alkaline layer mixture prepared in S1 into hopper B. The pre-pressure of hopper A is 5-10kN, and the final pressure of hopper B is 25-30kN. Spray 0.5% HPMC ethanol solution between the acid layer and the alkaline layer at a dosage of 0.5-1 mL / m², an atomized particle size of 10-15μm, a coverage rate of ≥95%, an interface pressure of 15kN, and maintain for 1s; obtain washing machine trough cleaning effervescent tablets.

10. The method for preparing the washing machine tank cleaning effervescent tablet according to claim 9, characterized in that: The 0.5% HPMC ethanol solution is prepared by the following scheme: 1 part HPMC is slowly added to 99 parts ethanol, the ethanol solution temperature is less than 10°C, and the rotation speed is 300-500 rpm. The solution is transferred to a 40-50°C water bath, and 100 parts of deionized water preheated to 40°C is gradually added. The mixture is stirred at 800-1000 rpm for 30 minutes, and then passed through a high-pressure homogenizer at a pressure of 20-50 MPa. The cycle is repeated 2-3 times to ensure that no particles remain.

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