Phosphorus-free laundry detergent based on enzyme preparation and preparation method of phosphorus-free laundry detergent

Abstract

The invention belongs to the technical field of laundry detergents, and particularly relates to a phosphorus-free laundry detergent based on an enzyme preparation and a preparation method of the phosphorus-free laundry detergent. The non-phosphorus laundry detergent based on the enzyme preparation is prepared from the following components in percentage by mass: 10 to 15 percent of anionic surfactant, 4 to 8 percent of nonionic surfactant, 1 to 3 percent of zwitterionic surfactant, 0.1 to 0.5 percent of papain preparation, 0.1 to 0.5 percent of lipase preparation, 1 to 3 percent of propylene glycol, 2 to 4 percent of trisodium citrate, 0.02 to 0.04 percent of polyether defoaming agent, 0.10 to 0.15 percent of citric acid and the balance of water. The laundry detergent prepared by the invention is strong in dirt-removing power and high in storage stability.

Description

Technical Field

[0001] This invention belongs to the field of laundry detergent technology, specifically relating to an enzyme-based phosphate-free laundry detergent and its preparation method. Background Technology

[0002] In the laundry detergent industry, laundry detergents containing bio-enzymes have garnered widespread attention due to their highly efficient ability to break down specific stains. Proteases effectively break down protein-based stains on clothing, such as blood, sweat, and food residue; while lipases are effective at removing grease-based stains. Theoretically, synergistic application of multiple enzymes in a laundry detergent system could achieve more comprehensive stain removal performance. However, in practical applications, compatibility issues between different enzymes limit the full realization of their effectiveness.

[0003] Especially in laundry detergent formulations, when proteases and lipases coexist, the proteases hydrolyze the molecular structure of the lipases, leading to a decrease in lipase activity or even inactivation. Furthermore, proteases themselves have poor stability in liquid environments and are easily affected by surfactants, chelating agents, bleaching agents, and other additives in the formulation, undergoing conformational changes or degradation, thereby reducing their catalytic activity. Simultaneously, under long-term storage conditions, enzyme preparations are prone to aggregation, precipitation, or chemical modification, resulting in a significant decrease in activity. Summary of the Invention

[0004] The purpose of this invention is to provide a phosphate-free laundry detergent based on an enzyme preparation and its preparation method.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A phosphate-free laundry detergent based on an enzyme preparation comprises the following components by weight percentage: 10-15% anionic surfactant, 4-8% nonionic surfactant, 1-3% amphoteric surfactant, 0.1-0.5% papain preparation, 0.1-0.5% lipase preparation, 1-3% propylene glycol, 2-4% trisodium citrate, 0.02-0.04% polyether defoamer, 0.10-0.15% citric acid, and the balance being water.

[0006] The method for preparing the papain preparation includes the following steps: (1) Adjust the pH of 1-2% sodium alginate aqueous solution to 5.5 with 1.5mol / L hydrochloric acid, cool to 10℃, and add methacrylic acid dropwise at a rate of 1-2 drops / second. The mass ratio of sodium alginate to methacrylic acid is 1:(1.3-1.5). After the dropwise addition is completed, heat to 30-40℃ and react in the dark for 15-20h. After the reaction is completed, use a dialysis bag to retain products with a molecular weight greater than or equal to 14000, freeze dry, and obtain modified sodium alginate. (2) Prepare a 2wt% solution of modified sodium alginate with water, add 0.1% ammonium persulfate by mass of modified sodium alginate, stir to dissolve, and obtain a mixture. Add the mixture dropwise to a 0.15mol / L calcium chloride aqueous solution at a rate of 1-2 drops / second. The CaCl2 aqueous solution also contains 0.03wt% N,N,N',N'-tetramethylethylenediamine. Stir at 100rpm at room temperature for 1 hour, let stand for 24 hours, discard the supernatant, wash with water 2-3 times to obtain blank microcapsules. (3) Mix the papain aqueous solution with an enzyme activity concentration of 100-110 U / mL with blank microcapsules and stir at 4℃ and 100 rpm for 4-6 h to allow the enzyme molecules to fully diffuse and adsorb into the porous network structure of the microcapsules. After loading, filter with a 0.45 μm filter membrane and wash gently twice with pre-cooled deionized water to obtain the papain preparation.

[0007] The method for preparing the lipase preparation includes the following steps: (1) Adjust the pH of 1-2% sodium alginate aqueous solution to 5.5 with 1.5mol / L hydrochloric acid, cool to 10℃, and add methacrylic acid dropwise at a rate of 1-2 drops / second. The mass ratio of sodium alginate to methacrylic acid is 1:(0.9-1.1). After the dropwise addition is completed, heat to 30-40℃ and react in the dark for 15-20h. After the reaction is completed, use a dialysis bag to retain products with a molecular weight greater than or equal to 14000, freeze dry, and obtain modified sodium alginate. (2) Prepare a 2wt% solution of modified sodium alginate with water, add 0.1% ammonium persulfate by mass of modified sodium alginate, stir to dissolve, and obtain a mixture. Add the mixture dropwise to a 0.15mol / L calcium chloride aqueous solution at a rate of 1-2 drops / second. The CaCl2 aqueous solution also contains 0.03wt% N,N,N',N'-tetramethylethylenediamine. Stir at 100rpm at room temperature for 1 hour, let stand for 24 hours, discard the supernatant, wash with water 2-3 times to obtain blank microcapsules. (3) Mix the lipase aqueous solution with an enzyme activity concentration of 100-110 U / mL with blank microcapsules and stir at 4℃ and 100 rpm for 4-6 h to allow the enzyme molecules to fully diffuse and adsorb into the porous network structure of the microcapsules. After loading, filter with a 0.45 μm filter membrane and wash gently twice with pre-cooled deionized water to obtain the lipase preparation.

[0008] Sodium alginate itself can only form ionic cross-linked structures through calcium ions, resulting in structures with large and uneven pore sizes. This invention uses modified sodium alginate to prepare empty capsules for enzyme loading, allowing proteases and lipases to coexist in laundry detergent, thus improving cleaning performance. This invention involves reacting sodium alginate with methacrylic acid to graft double bonds onto its molecular chain; subsequent free radical polymerization forms covalent bonds between these double bonds, adding another layer of covalently cross-linked network to the traditional structure. Furthermore, this invention precisely controls the mass ratio of sodium alginate to methacrylic acid according to the size of papain and lipase, and by precisely controlling the cross-linking density of modified sodium alginate, customizes the pore size of the microcapsule network, making it more compatible with lipases and proteases.

[0009] Preferably, the anionic surfactant comprises AES, sodium α-olefin sulfonate and sodium fatty acid methyl ester sulfonate in a mass ratio of 1:(1.3-1.6):(0.4-0.7).

[0010] Preferably, the nonionic surfactant is AEO-9.

[0011] Preferably, the zwitterionic surfactant is fatty amide propyl betaine.

[0012] Preferably, the defoamer is a polyether defoamer.

[0013] This invention utilizes specific surfactants that not only enhance detergency but also improve the stability of the laundry detergent. Even after three months of storage, it retains good detergency. Analysis suggests that the compounded surfactant system improves detergency, creates stable steric hindrance, prevents enzyme aggregation, and enhances overall system stability.

[0014] The method for preparing the enzyme-based phosphate-free laundry detergent includes the following steps: mixing the components of the enzyme-based phosphate-free laundry detergent evenly to obtain the enzyme-based phosphate-free laundry detergent.

[0015] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows: 1. This invention provides a phosphate-free laundry detergent with superior cleaning power for stubborn protein and fat stains. Traditional laundry detergents often cause eutrophication problems in water bodies due to their high phosphorus content. This product completely eliminates phosphorus-based additives, making it more environmentally friendly. Its superior stain removal efficiency stems from the synergistic effect of a unique compound enzyme system and a targeted surfactant system. Papain in the formula efficiently decomposes protein stains such as blood, milk, and sweat into water-soluble small peptides; while lipase selectively breaks down ester bonds in greases, emulsifying and decomposing large oil molecules, thus easily removing food oil stains, sebum, and other fatty stains. Simultaneously, the scientific compounding of multiple surfactants not only enhances the overall cleaning power but also creates a mild environment suitable for enzyme activity, ultimately achieving rapid and thorough removal of protein and fat stains, with significantly better washing and conditioning effects than similar phosphate-free products on the market. 2. The laundry detergent of this invention exhibits excellent storage stability. After being stored under varying temperature conditions for 90 days, testing revealed extremely low degradation rates in its core performance indicators of protein and fat removal, maintaining a high level of activity. The ingredients in the formula effectively maintain the physical stability of the laundry detergent system, preventing stratification and sedimentation. The encapsulated proteases and lipases are not easily deactivated during long-term storage. This stability ensures that consumers receive a consistently high-quality washing experience regardless of when they use the product. Detailed Implementation

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] All raw materials used in the following embodiments of the present invention are commercially available products: Papain, catalog number GC51809, Shanghai Guchen Biotechnology Co., Ltd.

[0018] Lipase, catalog number GC32618, Shanghai Guchen Biotechnology Co., Ltd.

[0019] Polyether defoamer, Jiangsu Haian Petrochemical Plant, propylene glycol block polyether L31.

[0020] Sodium fatty alcohol polyoxyethylene ether sulfate, AES, CAS No.: 68585-34-2.

[0021] Sodium α-alkenylsulfonate, CAS No.: 68439-53-6.

[0022] Sodium methyl ester sulfonate of fatty acids, CAS No.: 68439-55-8, Jinan Daorong Chemical Co., Ltd.

[0023] AEO-9, CAS No.: 68439-50-3.

[0024] Fatty amide propyl betaine, CAS No.: 61789-40-0.

[0025] APG0810, CAS No.: 68515-73-1.

[0026] Sodium alkylbenzene sulfonate, CAS No.: 25155-30-0.

[0027] Sodium alginate, product number S100126, Shanghai Aladdin Biochemical Technology Co., Ltd.

[0028] N,N,N',N'-Tetramethylethylenediamine, CAS No.: 110-18-9.

[0029] Example 1 This embodiment provides a phosphate-free laundry detergent based on an enzyme preparation, comprising the following components by weight percentage: 12% anionic surfactant, 6% nonionic surfactant, 2% amphoteric surfactant, 0.4% papain preparation, 0.4% lipase preparation, 2% propylene glycol, 3% trisodium citrate, 0.03% polyether defoamer, 0.12% citric acid, and the balance being water. The anionic surfactant is AES, sodium α-olefin sulfonate, and sodium fatty acid methyl ester sulfonate in a mass ratio of 1:1.4:0.6. The nonionic surfactant is AEO-9. The amphoteric surfactant is fatty amide propyl betaine. The defoamer is a polyether defoamer.

[0030] The method for preparing the papain preparation includes the following steps: (1) Adjust the pH of 2wt% sodium alginate aqueous solution to 5.5 with 1.5mol / L hydrochloric acid, cool to 10℃, and add methacrylic acid dropwise at a rate of 2 drops / second. The mass ratio of sodium alginate to methacrylic acid is 1:1.4. After the dropwise addition is completed, heat to 35℃ and react in the dark for 18h. After the reaction is completed, use a dialysis bag to retain products with a molecular weight greater than or equal to 14000, freeze dry, and obtain modified sodium alginate. (2) Prepare a 2wt% solution of modified sodium alginate with water, add 0.1% ammonium persulfate by mass of modified sodium alginate, stir to dissolve, and obtain a mixture. Add the mixture dropwise at a rate of 2 drops / second to an aqueous solution containing 0.15mol / L calcium chloride and 0.03wt% N,N,N',N'-tetramethylethylenediamine. Stir at 100rpm at room temperature for 1h, let stand for 24h, decant the supernatant, wash with water 3 times, filter until no more water flows down, and continue to filter for 1min to obtain blank microcapsules; (3) According to the ratio of 1.5 mL of papain aqueous solution to 1 g of blank microcapsule, the papain aqueous solution with an enzyme activity concentration of 100 U / mL was mixed with the blank microcapsule and stirred at 4℃ and 100 rpm for 5 h to allow the enzyme molecules to fully diffuse and adsorb into the porous network structure of the microcapsule. After loading, the mixture was filtered with a 0.45 μm filter membrane and gently washed twice with pre-cooled deionized water. The mixture was then filtered until no more water flowed down and then filtered for another 1 min to obtain the papain preparation.

[0031] The method for preparing the lipase preparation includes the following steps: (1) Adjust the pH of 1-2% sodium alginate aqueous solution to 5.5 with 1.5 mol / L hydrochloric acid, cool to 10°C, and add methacrylic acid dropwise at a rate of 2 drops / second. The mass ratio of sodium alginate to methacrylic acid is 1:1. After the dropwise addition is completed, heat to 35°C and react in the dark for 18 hours. After the reaction is completed, use a dialysis bag to retain products with a molecular weight greater than or equal to 14000. Freeze dry to obtain modified sodium alginate. (2) Prepare a 2wt% solution of modified sodium alginate with water, add 0.1% ammonium persulfate by mass of modified sodium alginate, stir to dissolve, and obtain a mixture. Add the mixture dropwise to a 0.15mol / L calcium chloride aqueous solution at a rate of 2 drops / second. The CaCl2 aqueous solution also contains 0.03wt% N,N,N',N'-tetramethylethylenediamine. Stir at 100rpm at room temperature for 1 hour, let stand for 24 hours, discard the supernatant, wash with water 3 times, filter until no more water flows down, and continue to filter for 1 minute to obtain blank microcapsules. (3) According to the ratio of 1.5 mL lipase aqueous solution to 1 g blank microcapsule, the lipase aqueous solution with an enzyme activity concentration of 100 U / mL was mixed with the blank microcapsule and stirred at 4℃ and 100 rpm for 5 h to allow the enzyme molecules to fully diffuse and adsorb into the porous network structure of the microcapsule. After loading, the mixture was filtered with a 0.45 μm filter membrane and gently washed twice with pre-cooled deionized water. The mixture was then filtered until no more water flowed down and then filtered for another 1 min to obtain the lipase preparation.

[0032] The method for preparing the enzyme-based phosphate-free laundry detergent includes the following steps: mixing the components of the enzyme-based phosphate-free laundry detergent evenly to obtain the enzyme-based phosphate-free laundry detergent.

[0033] Comparative Example 1 This comparative example is the product of Example 1 in CN118995684B, an enzyme preparation for laundry detergent that effectively improves washing performance.

[0034] Comparative Example 2 The difference between this comparative example and Example 1 is that AEO-9 is replaced with APG0810.

[0035] Comparative Example 3 The difference between this comparative example and Example 1 is that the anionic surfactant includes AES, sodium α-olefin sulfonate, and sodium fatty acid methyl ester sulfonate in a mass ratio of 1.7:0.3.

[0036] Comparative Example 4 The difference between this comparative example and Example 1 is that the anionic surfactant includes AES, sodium α-olefin sulfonate, and sodium fatty acid methyl ester sulfonate in a mass ratio of 0.9:1.2:0.8.

[0037] Comparative Example 5 The difference between this comparative example and Example 1 is that the anionic surfactant includes AES, sodium alkylbenzene sulfonate, and sodium fatty acid methyl ester sulfonate in a mass ratio of 1:1.4:0.6.

[0038] Comparative Example 6 The difference between this comparative example and Example 1 is that the mass ratio of sodium alginate to methacrylic acid in the preparation of the papain preparation is 1:1.2.

[0039] Comparative Example 7 The difference between this comparative example and Example 1 is that the mass ratio of sodium alginate to methacrylic acid in the preparation of the papain preparation is 1:1.6.

[0040] Comparative Example 8 The difference between this comparative example and Example 1 is that the mass ratio of sodium alginate to methacrylic acid in the preparation of the lipase preparation is 1:0.8.

[0041] Comparative Example 9 The difference between this comparative example and Example 1 is that the mass ratio of sodium alginate to methacrylic acid in the preparation of the lipase preparation is 1:1.2.

[0042] Performance testing The performance of the laundry detergents prepared in Example 1 and Comparative Examples 1-9 was tested according to GB / T13174-2021 "Determination of detergency and recycle performance of detergents for clothing". Samples were prepared with 250 mg / kg hard water to a concentration of 0.3 wt%, and the detergency ratios of the samples on protein (JB-02) and sebum (JB-03) soiled fabrics were statistically analyzed. The performance of freshly prepared laundry detergents and detergents stored for 90 days (4℃, 25℃, 45℃ for 24 hours sequentially, constituting one cycle, for a total of 30 cycles) was also tested.

[0043] The results are shown in Table 1.

[0044] Table 1 Performance Test Results

[0045] As shown in Table 1, when the laundry detergent of Example 1 is freshly prepared, its stain removal effect is comparable to that of the prior art laundry detergent in Comparative Example 1. However, after storage under variable temperature conditions, the stain removal effect of Example 1 remains stable, while the stain removal power of the prior art product decreases under variable temperature conditions.

[0046] In Comparative Example 2, AEO-9 was replaced with APG0810. In Comparative Examples 3-5, the composition and ratio of the anionic surfactants were different, and the detergency decreased. The analysis shows that the surfactant composition of the present invention has a synergistic effect, which helps the system reach the critical micelle concentration and significantly improves the detergency.

[0047] Because lipase has a larger molecular weight than papain, the mass ratio of sodium alginate to methacrylic acid differed in the preparation of the papain formulations in Comparative Examples 6 and 7. When the mass ratio was too low, the network pores were relatively large, and the protease might enter the lipase formulation during storage, causing lipase decomposition. Simultaneously, the protease would be inactivated in the laundry detergent, resulting in a decrease in the cleaning effect of both protein and fat after storage. When the mass ratio was too high, the network structure was too dense, making it difficult for papain to smoothly enter the capsules, leading to a lower effective content of papain in the capsules and a decrease in the cleaning effect of the laundry detergent on protein.

[0048] In the preparation of the lipoprotein esters in Comparative Examples 8 and 9, the mass ratio of sodium alginate to methacrylic acid differed. When the mass ratio was too low, the network pores were relatively large, and the lipase was easily deactivated in the laundry detergent during storage, resulting in a decrease in its grease-removing effect. When the mass ratio was too high, the network structure was too dense, making it difficult for the lipoprotein ester to enter the capsule smoothly. This reduced the effective content of papain in the capsule, further decreasing the laundry detergent's grease-removing effect.

[0049] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A phosphate-free laundry detergent based on an enzyme preparation, characterized in that, The product comprises the following components by mass percentage: 10-15% anionic surfactant, 4-8% nonionic surfactant, 1-3% amphoteric surfactant, 0.1-0.5% papain preparation, 0.1-0.5% lipase preparation, 1-3% propylene glycol, 2-4% trisodium citrate, 0.02-0.04% polyether defoamer, 0.10-0.15% citric acid, with the balance being water.

2. The phosphate-free laundry detergent based on enzyme preparations according to claim 1, characterized in that, The method for preparing the papain preparation includes the following steps: (1) Add methacrylic acid dropwise to sodium alginate aqueous solution, heat to 30-40℃ and react in the dark for 15-20h. After the reaction is completed, dialyze and freeze dry to obtain modified sodium alginate A. (2) Prepare a solution of modified sodium alginate A with water, add ammonium persulfate, stir to dissolve, and obtain a mixture. Add the mixture dropwise to an aqueous solution containing calcium chloride and N,N,N',N'-tetramethylethylenediamine, stir at room temperature, let stand, remove the supernatant, wash, and obtain blank microcapsules A; (3) Mix the papain aqueous solution with blank microcapsule A, stir, filter, and wash to obtain the papain preparation.

3. The phosphate-free laundry detergent based on enzyme preparations according to claim 2, characterized in that, The mass ratio of sodium alginate to methacrylic acid used in the preparation of modified sodium alginate A is 1:(1.3-1.5).

4. The phosphate-free laundry detergent based on enzyme preparations according to claim 1, characterized in that, The method for preparing the lipase preparation includes the following steps: (1) Add methacrylic acid dropwise to sodium alginate aqueous solution, heat to 30-40℃ and react in the dark for 15-20h. After the reaction is completed, dialyze and freeze dry to obtain modified sodium alginate B. (2) Prepare a solution of modified sodium alginate B with water, add ammonium persulfate, stir to dissolve, and obtain a mixture. Add the mixture dropwise to an aqueous solution containing calcium chloride and N,N,N',N'-tetramethylethylenediamine, stir at room temperature, let stand, remove the supernatant, wash, and obtain blank microcapsule B. (3) Mix papain aqueous solution with blank microcapsule B, stir, filter, and wash to obtain lipase preparation.

5. The phosphate-free laundry detergent based on enzyme preparations according to claim 4, characterized in that, The mass ratio of sodium alginate to methacrylic acid used in the preparation of modified sodium alginate B is 1:(0.9-1.1).

6. The phosphate-free laundry detergent based on enzyme preparations according to claim 1, characterized in that, Anionic surfactants include sodium fatty alcohol polyoxyethylene ether sulfate, sodium α-alkenyl sulfonate, and sodium fatty acid methyl ester sulfonate in a mass ratio of 1:(1.3-1.6):(0.4-0.7).

7. The phosphate-free laundry detergent based on enzyme preparations according to claim 1, characterized in that, The nonionic surfactant is AEO-9.

8. The phosphate-free laundry detergent based on enzyme preparations according to claim 1, characterized in that, The zwitterionic surfactant is fatty amide propyl betaine.

9. The phosphate-free laundry detergent based on enzyme preparations according to claim 1, characterized in that, The defoamer is a polyether defoamer.

10. A method for preparing a phosphate-free laundry detergent based on an enzyme preparation according to any one of claims 1-9, characterized in that, Includes the following steps: The components of the enzyme-based phosphate-free laundry detergent are mixed evenly to obtain the enzyme-based phosphate-free laundry detergent.

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