A stable weakly acidic concentrated laundry liquid and a method for its preparation

Abstract

The application provides a kind of stable weak acid concentrated laundry liquid, including the following components by mass fraction: alpha-hexyl-omega-hydroxyl poly (oxidized-1,2-ethanediy) 4-10%, alkyl glycoside 1-3%, fatty acid methyl ester ethoxylate 4-10%, sodium secondary alkyl sulfonate 5-15%, other surfactants 25-32%, solvent 5-15%, auxiliary 0.1-10%, and the balance of water. The application provides a kind of stable weak acid concentrated laundry liquid and its preparation method, which does not contain dodecyl benzene sulfonic acid, introduces a variety of plant-based surfactants, and has good stability under weak acid conditions (pH=6.0-6.9). Using the technical scheme of the application, the formula can be mild, low-foaming and easy to rinse. The application develops a kind of sulfonic acid-free, green and mild weak acid concentrated laundry liquid, solves the problems existing in the prior art, and meets the current market demand.

Description

Technical Field

[0001] This invention relates to the field of detergent technology, and mainly to a stable, weakly acidic concentrated laundry detergent and its preparation method. Background Technology

[0002] Laundry detergent is one of the most commonly used cleaning agents in daily life. Compared to the more common laundry powder, laundry detergent has advantages such as better washing performance at low temperatures, rapid dissolution, and ease of use. As the drawbacks of large-bottle laundry detergent become increasingly apparent, consumers are shifting their focus towards concentrated laundry detergent. Concentration, environmental friendliness, and high-efficiency functionality will be the development trends of the laundry industry.

[0003] To meet the demands of green development and achieve green products, detergent products are increasingly using surfactants derived from natural plants, such as natural fatty alcohol polyoxyethylene ethers (C12-14AEO series nonionic surfactants), sodium sulfate of natural fatty alcohol polyoxyethylene ethers (AES), fatty acid methyl ester ethoxylates (FMEE), natural alkyl glycosides (C12-14 APG), cocamidopropyl betaine (CAB), and amino acid surfactants.

[0004] As is well known, dodecylbenzenesulfonic acid combines with sodium hydroxide in laundry detergent to form sodium dodecylbenzenesulfonate, which has a good cleaning effect and is inexpensive, making it an indispensable ingredient in traditional sulfonic acid-based detergent formulations. However, most commercially available traditional sulfonic acid-based concentrated laundry detergents are alkaline, while a slightly acidic environment is the closest physiological condition to skin. Prolonged contact with irritating alkaline concentrated laundry detergents during hand washing can cause skin damage. Furthermore, alkaline concentrated laundry detergents can also damage clothing. Therefore, providing a slightly acidic, gentle concentrated laundry detergent product has broad market prospects in the daily chemical industry and meets consumer demand.

[0005] Patent application number 202210660429.8 discloses a weakly acidic ultra-concentrated laundry detergent and its preparation method. Its components contain a high proportion of dodecylbenzene sulfonic acid, making it a typical sulfonic acid-based detergent. Sulfonic acid can provide good anti-gelling effects in concentrated laundry detergents. However, sulfonic acid-based detergents also have certain drawbacks: firstly, the dodecylbenzene carbon chain is derived from petrochemicals, making it less environmentally friendly; secondly, sodium dodecylbenzene sulfonate has strong degreasing ability, which can irritate the skin during hand washing and leaves clothes with a poor feel after washing.

[0006] In conclusion, there is an urgent need to research and develop a sulfonic acid-free, green, and mild weakly acidic concentrated laundry detergent to solve the problems existing in the current technology and meet the current market demand. Summary of the Invention

[0007] This invention provides a stable, weakly acidic concentrated laundry detergent and its preparation method. It is free of dodecylbenzene sulfonic acid and incorporates various plant-based surfactants, exhibiting good stability under weakly acidic conditions (pH=6.0-6.9). Using the technical solution of this invention, a mild, low-foaming, and easy-to-rinse formula can be achieved.

[0008] One object of the present invention is to provide a stable, weakly acidic concentrated laundry detergent, said stable, weakly acidic concentrated laundry detergent comprising the following components by mass fraction: α-Hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl) 4-10% Alkyl glycosides 1-3% Fatty acid methyl ester ethoxylates 4-10% Sodium secondary alkyl sulfonate 5-15% Other surfactants 25-32% Solvent 5-15% Additives 0.1-10% Water balance.

[0009] Furthermore, the fatty acid methyl ester ethoxylate has the following general structural formula: ; Where X is selected from integers from 3 to 12, and R is selected from plant carbon chains C12-C14 derived from coconut oil.

[0010] Furthermore, the other surfactants are selected from at least two of anionic surfactants, nonionic surfactants, and amphoteric surfactants.

[0011] Furthermore, the anionic surfactant is selected from one or more of alkyl sulfates, fatty alcohol polyoxyethylene sulfates, fatty alcohol polyoxyethylene carboxylates, fatty acid methyl ester sulfonates, and fatty acid salts.

[0012] Furthermore, the nonionic surfactant is selected from one or more of fatty alcohol polyoxyethylene ethers and Sapindus mukorossi saponins.

[0013] Furthermore, the zwitterionic surfactant is selected from one or more of amino acid-type surfactants and betaine-type surfactants.

[0014] Furthermore, the mass fraction of the anionic surfactant is preferably 5-20%, the mass fraction of the nonionic surfactant is preferably 20-40%, and the mass fraction of the amphoteric surfactant is preferably 0.2-5%.

[0015] Furthermore, the additives are selected from one or more of the following: preservatives, anti-redeposition agents, enzyme preparations, solvents, light-stable bleaching agents, neutralizing agents, fragrances, pigments, salts, chelating agents, and optical brighteners.

[0016] Furthermore, the sodium secondary alkyl sulfonate is preferably present in a mass fraction of 10-15%. Sodium secondary alkyl sulfonate (SAS) is an environmentally friendly, foam-rich anionic surfactant suitable for household cleaning, especially when compounded with nonionic surfactants, resulting in a dramatic increase in foam. In the hydrophilic group of sodium secondary alkyl sulfonate, the sulfonic acid group is always in the middle position, thus giving the product excellent penetration power.

[0017] Furthermore, the preservative is selected from one or more of methylisothiazolinone, chloromethylisothiazolinone, phenoxyethanol, sodium benzoate, methylchloroisothiazolinone, benzisothiazolinone, isothiazolinone and its derivatives.

[0018] Furthermore, the anti-redeposition agent is selected from one or more of sodium polyacrylate, maleic acrylic acid copolymer, carboxymethyl cellulose, and homopolymers and copolymers of vinylpyrrolidone.

[0019] Furthermore, the enzyme preparation is selected from one or more of protease, cellulase, lipase, amylase, mannanase, and pectinase.

[0020] Furthermore, the solvent is selected from one or more of glycerol, propylene glycol, ethanol, polyethylene glycol, and isopropanol.

[0021] Furthermore, the photostable bleaching agent is selected from one or more of hypochlorite bleaching agents and peroxide bleaching agents; the peroxide bleaching agent is a percarbonate or a perborate.

[0022] Furthermore, the neutralizing agent is selected from one or more of sodium hydroxide, potassium hydroxide, monoethanolamine, and triethanolamine.

[0023] Furthermore, the fragrance is selected from any fragrance ingredients suitable for detergent products, which can be of natural origin or chemically synthesized products, such as fruity or floral fragrances.

[0024] Furthermore, the pigment is selected from any dye or pigment suitable for use in washing products.

[0025] Furthermore, the salt is selected from one or more of sodium citrate, borax, disodium ethylenediaminetetraacetate, sodium percarbonate, sodium gluconate, sodium tartrate, and sodium oxalate.

[0026] Another object of the present invention is to provide a method for preparing the stable weakly acidic concentrated laundry detergent, the method comprising the following steps: S1. Add water and solvent to the container, heat to a higher temperature, add sodium secondary alkyl sulfonate and α-hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl) and stir until completely dissolved; S2. Stop heating, add the remaining surfactant, stir well, add the remaining water, and adjust the pH after cooling. S3. Add other ingredients and stir until completely dissolved to obtain the stable weakly acidic concentrated laundry detergent.

[0027] Furthermore, in step S1, the heating temperature is 50-70℃, and in step S2, the cooling temperature is 30-50℃.

[0028] Furthermore, the pH in step S2 is 6-7.

[0029] The present invention has the following beneficial effects: 1. The stable, weakly acidic concentrated laundry detergent composition of the present invention is a formulation system without sodium dodecylbenzene sulfonate, wherein the active ingredient is mainly a surfactant with natural plant-based carbon chains. In this invention, the anionic surfactant sodium secondary alkyl sulfonate is compounded with a special nonionic surfactant α-hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl)sulfonate. Because α-hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl)sulfonate has many sterically hindered groups, and sodium secondary alkyl sulfonate has a branched structure and excellent hydrophilicity, the combination of these two substances can prevent the linear hydrophobic carbon chain micelles of the surfactant molecules from entanglement and aggregation, achieving a good dispersion effect and exhibiting good solubilizing, anti-aggregation, and gelling properties. Furthermore, by further compounding with other surfactants, this invention solves the technical problem of instability of high-concentration surfactants in weakly acidic systems (pH=6.0-6.9), enabling the product to maintain a stable and uniform system under various temperature conditions, thus improving product stability.

[0030] 2. We also unexpectedly discovered that the concentrated laundry detergent of the present invention, while having good stability, can achieve low foaming and easy rinsing without the addition of fatty acids by rationally compounding sodium isomeric alcohol ether sulfate with α-hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl) sulfate, leaving hands dry and without stickiness after washing. Detailed Implementation

[0031] To more clearly illustrate the technical solution of the present invention, the following embodiments are provided. Unless otherwise stated, the raw materials, reactions, and post-processing methods appearing in the embodiments are all commercially available raw materials and technical methods well known to those skilled in the art.

[0032] The terms "preferred," "more preferably," and "more suitable" used in this invention refer to embodiments of the invention that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this invention.

[0033] It should be understood that, except in any operational instance or otherwise indicated, the amounts or all figures representing ingredients used, for example, in the specification and claims, should be understood to be modified by the term "about" in all cases. Therefore, unless otherwise stated, the numerical parameters set forth in the following specification and appended claims are approximate values ​​varying according to the desired performance to be obtained according to the invention.

[0034] In the examples and comparative examples, the following substances will be used and have the stated functions, and all preparations will take place at 25°C.

[0035] In the embodiments described, the following abbreviations will be used and will have the indicated functions.

[0036] Citric acid, pH adjuster, purchased from Guangzhou Reagent Factory.

[0037] Sodium citrate, a chelating agent, was purchased from Guangzhou Reagent Factory.

[0038] Propylene glycol, solvent, purchased from Guangzhou Reagent Factory.

[0039] SAS 60, sodium alkyl sulfonate, anionic surfactant, purchased from Shanghai Sokai Industrial Co., Ltd.

[0040] CS 6250, α-hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl) , is a nonionic surfactant, part of the BASF Lutensol CS 6250 series.

[0041] AES, fatty alcohol polyoxyethylene sulfate, fatty alcohol with 12-14 carbon atoms, average degree of ethoxylation 2, anionic surfactant, purchased from Huijintong Fine Chemicals Co., Ltd.

[0042] AEO9, fatty alcohol polyoxyethylene ether, fatty alcohol with 12-14 carbon atoms, average degree of ethoxylation of 9, nonionic surfactant, purchased from BASF.

[0043] Disodium cocoyl glutamate, an amphoteric surfactant, was purchased from Nanjing Zhongshi Chemical Co., Ltd.

[0044] CAB, cocamidopropyl betaine, an amphoteric surfactant, was purchased from Guangzhou Tinci Advanced Materials Co., Ltd.

[0045] APG, alkyl glycoside, nonionic surfactant, purchased from Shanghai Fakai.

[0046] FMEE, fatty acid methyl ester ethoxylate, is a nonionic surfactant with the following structure: Wherein, R represents the carbon chain of coconut oil-derived plant (C12-14); X represents the average degree of ethoxylation (EO number), preferably an integer from 3 to 12, purchased from China National Light Industry Chemical Technology Co., Ltd.

[0047] TO8 is an isomeric alcohol ether, a nonionic surfactant, and is a product of the Lutensol TO series from BASF (China) Co., Ltd.

[0048] The preservative, a mixture of methylisothiazolinone and chloromethylisothiazolinone, was purchased from IFF.

[0049] The protease, alkaline protease, brand name UNO series product, was purchased from Novozymes (China) Biotechnology Co., Ltd.

[0050] The fragrance was purchased from Givaudan Fragrance Company.

[0051] Unless otherwise stated, the water used in the embodiments of this invention is deionized water.

[0052] Example The composition of the laundry detergent samples in Examples 1-4 is shown in Table 1.

[0053] Table 1. Composition and proportions of concentrated laundry detergent in Examples 1-4 The preparation method of the concentrated laundry detergent in Examples 1-4 includes the following steps: S1. According to the above mass fraction, add 20 wt% water to the preparation container, then add propylene glycol, heat to 60℃, add SAS 60 and CS 6250, and stir until completely dissolved; S2. Stop heating and reduce the temperature to below 50℃. Add TO8, AEO9, disodium cocoyl glutamate, CAB, APG and FMEE, stir well, and add citric acid to adjust the pH to 6.5. S3. Further reduce the temperature to 40°C, add the remaining ingredients, and stir until completely dissolved to obtain the stable, weakly acidic concentrated laundry detergent.

[0054] Comparative Examples 1-3 were set up based on Example 1, with the following differences from Example 1: In Comparative Example 1, SAS 60 and CS6250 were not added to the concentrated laundry detergent, and the amounts of AES, AEO9 and FMEE were increased; In Comparative Example 2, the amount of SAS 60 was reduced and CS6250 was not added, and the amount of AEO9 was increased; In Comparative Example 3, SAS 60 was removed and the amounts of AES and AEO9 were increased.

[0055] The composition of the laundry detergent samples in Comparative Examples 1-3 is shown in Table 2.

[0056] Table 2. Composition ratio of concentrated laundry detergent in Comparative Examples 1-3 Test case Key performance characteristics of the laundry detergent samples prepared in Examples 1-4 and Comparative Examples 1-3 were tested.

[0057] 1. Stability Test Test method: Low temperature stability: Place the sample in a 0℃ environment for 4 weeks and observe its appearance; High temperature stability: Place the sample in an environment of 45℃ for 4 weeks and observe its appearance; Freeze-thaw cycle: Place the sample at -15℃ for 24 h, then return it to room temperature for 24 h; repeat the cycle 4 times, return it to room temperature, and observe the appearance. Thermal cycling: Place the sample at 45℃ for 24 h, then at -15℃ for 24 h; cycle 4 times, then return to room temperature and observe the appearance.

[0058] The results are shown in Table 3.

[0059] Table 3. Stability test results of concentrated laundry detergents in Examples 1-4 and Comparative Examples 1-3 The stability test results in Table 3 show that the concentrated laundry detergents of Examples 1-4 maintained stability at all test temperatures, while Comparative Examples 1-3 exhibited white turbidity at low temperatures. This is because the α-hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl) group in the concentrated laundry detergents of Examples 1-4 has sterically hindered groups and good compatibility with sodium secondary alkyl sulfonate. Simultaneously, sodium secondary alkyl sulfonate has a branched structure and good hydrophilicity. The combination of these two components prevents the entanglement and aggregation of linear hydrophobic carbon chain micelles of surfactant molecules, achieving a better dispersion effect and exhibiting good solubilizing, anti-aggregation, and gelling properties. This allows the product to form a stable and uniform system under various temperature conditions.

[0060] 2. Foam test The laundry detergent samples prepared in Examples 1-4 and Comparative Examples 1-3 were tested according to the Roche foaming method in GB / T 13173 "Test Methods for Surfactants and Detergents". In the tests, the concentration of concentrated laundry detergent was 2.5 g / L, and the hard water concentration was 150 ppm. Record the initial volume of the foam and the volume after 5 min and 10 min.

[0061] The results are shown in Table 4.

[0062] Table 4. Foam test results of concentrated laundry detergents in Examples 1-4 and Comparative Examples 1-3 As shown by the foam test data in Table 4, after more than 5 minutes of observation, the foam volume of Examples 1-4 decreased significantly, indicating that the concentrated laundry detergent is low-foaming and easy to rinse. However, Comparative Examples 1-3, which removed or replaced sodium secondary alkyl sulfonate and α-hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl) oxide, had very high foam volumes both initially and after standing, and the foam volume decreased at a slower rate, making them difficult to rinse.

[0063] 3. Stickiness test Forty participants were selected to conduct a post-wash stickiness evaluation test on laundry detergent samples prepared in Examples 1-4 and Comparative Examples 1-3. The test method is as follows: (1) Prepare 2 L of tap water and the corresponding clothes to be washed for each laundry detergent sample; (2) Add one pump (4 mL) of laundry detergent sample to 2 L of tap water, mix evenly, soak the clothes until they are completely wet, and then wash normally until clean. (3) After washing, take out the clothes and wring them dry; rinse each with 3 L of clean water twice, and wash and rub your hands 5 times each time. (4) After rinsing, conduct post-wash evaluation and count the number of votes cast by 40 people on the post-wash experience of the samples of Examples 1-4 and Comparative Examples 1-3. Each person can only cast 1 vote for the same sample.

[0064] Table 5. Foam test results of concentrated laundry detergents in Examples 1-4 and Comparative Examples 1-3 The stickiness test data in Table 5 shows that, for Examples 1-4, which are samples formulated with sodium secondary alkyl sulfonate and α-hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl) oxide, more than half of the participants felt that their hands were dry and had no slippery feeling after washing; while for Comparative Examples 1-3, a few people felt no slippery feeling, and more than half of the participants felt a certain degree of slipperiness after washing. It can be seen that the present invention uses a specific surfactant formulation, which can significantly improve the problem of slippery feeling on hands after washing with concentrated laundry detergent.

[0065] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0066] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A stable, weakly acidic concentrated laundry detergent, characterized in that, The stable, weakly acidic concentrated laundry detergent consists of the following components by mass fraction: composition: α-Hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl) 4-10% Alkyl glycosides 1-3% Fatty acid methyl ester ethoxylates 4-10% Sodium secondary alkyl sulfonate 5-15% Other surfactants 25-32% Solvent 5-15% Additives 0.1-10% Water balance; The fatty acid methyl ester ethoxylate has the following general structural formula: ； Where X is selected from integers from 3 to 12, and R is selected from carbon chains from C12 to C14; The other surfactants are selected from at least two of anionic surfactants, nonionic surfactants, and amphoteric surfactants; The pH of the weakly acidic concentrated laundry detergent is 6-6.9; The anionic surfactant is selected from one or more of alkyl sulfates, fatty alcohol polyoxyethylene sulfates, fatty alcohol polyoxyethylene carboxylates, fatty acid methyl ester sulfonates, and fatty acid salts. The nonionic surfactant is selected from one or more of fatty alcohol polyoxyethylene ether AEO9 and isomeric alcohol ethers; The additives are selected from one or more of the following: preservatives, anti-redeposition agents, enzyme preparations, light-stabilizing bleaching agents, neutralizing agents, fragrances, pigments, chelating agents, and optical brighteners. The solvent is selected from one or more of glycerol, propylene glycol, ethanol, polyethylene glycol, and isopropanol.

2. The stable, weakly acidic concentrated laundry detergent according to claim 1, characterized in that, The zwitterionic surfactant is selected from one or more of amino acid-type surfactants and betaine-type surfactants.

3. The method for preparing the stable, weakly acidic concentrated laundry detergent according to any one of claims 1-2, characterized in that, The method for preparing the stable, weakly acidic concentrated laundry detergent includes the following steps: S1. Add water and solvent to the container, heat to a higher temperature, add sodium secondary alkyl sulfonate and α-hexyl-ω-hydroxy poly(oxy-1,2-ethylenedimethyl) and stir until completely dissolved; S2. Stop heating, add the remaining surfactant, stir well, add the remaining water, and adjust the pH after cooling. S3. Add other ingredients and stir until completely dissolved to obtain the stable weakly acidic concentrated laundry detergent.

4. The method for preparing the stable weakly acidic concentrated laundry detergent according to claim 3, characterized in that, In step S1, the heating temperature is 50-70℃, and in step S2, the cooling temperature is 30-50℃.

5. The method for preparing the stable weakly acidic concentrated laundry detergent according to claim 3, characterized in that, The pH value mentioned in step S2 is 6-7.

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