Quaternary ammonium salt complex bacteriostatic detergent and preparation method thereof

Abstract

The present application relates to the technical field of daily chemical bacteriostatic detergent, and provides a quaternary ammonium salt compound bacteriostatic detergent and a preparation method thereof, wherein lauric acid dodecyl glucoside esterification crude product, dodecyl glucoside, glycerol and deionized water are used to construct a lamellar liquid crystal phase, and benzalkonium chloride and dipentadecyldimethylammonium chloride are distributed in the interlayer region, and then the pH value of the system is adjusted by citric acid. The system can maintain the stability of the lamellar liquid crystal phase, storage uniformity, filtration and filling stability and mild moisturizing property, and is conducive to taking into account the bacteriostatic performance and processing fluidity, reducing the viscosity fluctuation, increasing the gel particles and the risk of stratification. The system can solve the problem that the structural stability, high efficient bacteriostatic performance, low viscosity wide processing window and mild moisturizing and low stimulation performance are difficult to be taken into account, and is suitable for the fields of cleaning and nursing and surface cleaning.

Description

Technical Field

[0001] This invention relates to the field of antibacterial detergent formulation technology, specifically to a quaternary ammonium salt compound antibacterial detergent and its preparation method. Background Technology

[0002] As the requirements for antibacterial detergents in cleaning and surface care applications continue to increase, the relevant systems not only need to possess antibacterial properties but also need to consider the stability of the lamellar liquid crystal phase, storage homogeneity, filtration and filling stability, low viscosity, and a wide processing window. For systems containing crude esterified lauryl glucoside, lauryl glucoside, glycerol, and deionized water, the degree of order of the liquid crystal phase, the interlayer hydration state, and the spatial distribution of active components all affect flowability, moisturizing properties, and stability. Therefore, how to maintain mild moisturizing and low-irritation characteristics while ensuring good processing compatibility and structural stability has become a key technical issue in the formulation design of antibacterial detergents.

[0003] Existing technologies have explored two pathways: liquid crystal structure regulation and quaternary ammonium salt compounding. For example, Chinese patent CN104130874A discloses a liquid detergent composition with a liquid crystal phase structure and a method for adjusting its fluid properties, showing that the liquid crystal phase structure can improve the fluid behavior and structural state of the detergent. Another example is Chinese patent CN111436429A, which discloses an environmental disinfectant composition and its preparation method, using benzalkonium chloride and disdecyldimethylammonium chloride as the main active components, emphasizing the antimicrobial effect of quaternary ammonium salt compounding. Combining these two types of disclosures, it can be inferred that although existing technologies cover both liquid crystal phase construction and quaternary ammonium salt synergistic antibacterial effects, simultaneously achieving stability of the layered liquid crystal phase, adaptability for filtration and filling, gentle moisturizing, and effective antibacterial properties in the same detergent system remains a challenge in achieving a simultaneous balance between structural and functional aspects. Summary of the Invention

[0004] The purpose of this invention is to provide a quaternary ammonium salt compound antibacterial detergent and its preparation method. This addresses the problem that in existing technologies, to improve the stability, storage uniformity, and filtration / filling stability of the lamellar liquid crystal phase of the detergent system, the active components are typically confined by enhancing the ordered lamellar structure constructed from esterified alkyl glucosides / alkyl glucosides / glycerol. However, this approach can easily lead to excessive binding, free migration, and decreased interfacial contact ability of the quaternary ammonium salt in the interlayer region, which is detrimental to the full realization of antibacterial properties. Furthermore, to improve the antibacterial activity and onset speed of benzalkonium chloride and dicedyldimethylammonium chloride, existing technologies often increase the quaternary ammonium salt loading or the proportion of free active components, thereby disturbing the interlayer water... The balance between chemical composition and interface leads to viscosity fluctuations, increased gel particles, layering, and decreased processing stability. Meanwhile, in order to achieve mild moisturizing and low-irritation properties, existing technologies often increase the glycerol content and enhance the orderliness of the lamellar liquid crystal to construct a water-retaining and slow-release interface. However, this can easily cause structural thickening, decreased flowability, and narrowing of the filtration and filling window. On the other hand, diluting the system or weakening the liquid crystal structure in order to improve low viscosity and processing flowability will weaken the water-retaining barrier and mildness, and increase the irritation of free surfactants. As a result, it is difficult to achieve both the structural stability and high-efficiency antibacterial properties, as well as the low viscosity and wide processing window and mild moisturizing and low-irritation properties.

[0005] This invention forms a layered liquid crystal phase by esterifying crude product of laurate dodecyl glucoside, dodecyl glucoside, glycerol and deionized water, and distributes benzalkonium chloride and dicedyldimethylammonium chloride in the interlayer region. While maintaining a stable and ordered structure and storage uniformity, it avoids excessive binding of quaternary ammonium salts or excessive dilution of the system, thus taking into account antibacterial properties, processing flowability and mild moisturizing properties.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A quaternary ammonium salt compound antibacterial detergent, based on 100 parts by weight of the total composition, comprises: 0.50-3.00 parts by weight of crude esterified product of dodecyl glucoside laurate, 1.50-6.00 parts by weight of dodecyl glucoside, 0.03-0.15 parts by weight of benzalkonium chloride, 0.02-0.08 parts by weight of decyl dimethyl ammonium chloride, 1.00-4.00 parts by weight of glycerin, 0.05-0.25 parts by weight of citric acid, and deionized water to make up to 100 parts by weight;

[0008] The crude esterified product of laurate-dodecyl glucoside is obtained by esterification of dodecyl glucoside with laurate. The detergent contains a layered liquid crystal phase formed by the crude esterified product of laurate-dodecyl glucoside, dodecyl glucoside, glycerol and deionized water. The interlayer spacing of the layered liquid crystal phase is 4.0-9.0 nm. The pH value of the detergent is 5.5-6.8. Benzalkonium chloride and dicedyldimethylammonium chloride are distributed in the interlayer region of the layered liquid crystal phase.

[0009] Furthermore, the crude product of laurate dodecyl glucoside esterification is prepared by the following steps:

[0010] A1. Mix 100 parts by weight of dodecyl glucoside, 20-70 parts by weight of lauric acid, and 0.2-2.0 parts by weight of p-toluenesulfonic acid monohydrate relative to 100 parts by weight of the dodecyl glucoside.

[0011] A2. React at 110-135℃ for 2-6 hours under nitrogen protection, and remove the water generated in the reaction under a pressure of 0.005-0.020MPa.

[0012] A3. The esterification reaction ends when the acid value of the reaction system drops to 15-40 mg KOH / g.

[0013] A4. Add 0.5-3.0 parts by weight of sodium bicarbonate relative to 100 parts by weight of dodecyl glucoside in step A1, neutralize to pH 6.0-7.5, filter, and obtain the crude esterified product of dodecyl glucoside laurate.

[0014] Furthermore, the crude product of laurate dodecyl glucoside esterification is further processed into a layered liquid crystal intermediate through the following steps:

[0015] B1. Mix 5-30 parts by weight of crude esterified product of lauryl glucoside, 15-60 parts by weight of lauryl glucoside, 10-40 parts by weight of glycerol and 10-110 parts by weight of deionized water to make a total mixture of 140 parts by weight.

[0016] B2. Stir at 200-800 rpm for 20-60 minutes at 50-65℃.

[0017] B3. Let stand at 20-30℃ for 8-24 hours.

[0018] B4. Obtain the layered liquid crystal intermediate with an interlayer spacing of 4.0-9.0 nm.

[0019] Furthermore, the quaternary ammonium salt intercalated layered liquid crystal intermediate is prepared through the following steps:

[0020] C1. Take 140 parts by weight of the layered liquid crystal intermediate, and add 0.3-1.5 parts by weight of benzalkonium chloride and 0.2-0.8 parts by weight of decyldimethylammonium chloride.

[0021] C2. Stir at 200-800 rpm for 10-30 minutes at 20-35℃.

[0022] C3. Obtain the quaternary ammonium salt intercalated layered liquid crystal intermediate with an interlayer spacing of 4.0-9.0 nm.

[0023] As a concept of this invention, the present invention employs a design that synergistically constructs a layered liquid crystal phase using crude laurate dodecyl glucoside esterification product, dodecyl glucoside, glycerol, benzalkonium chloride, and dicedyldimethylammonium chloride. This design primarily aims to achieve a synergistic balance between the stability and antibacterial properties of the layered liquid crystal phase. In existing technologies, to improve storage uniformity, filtration and filling stability, and mild moisturizing properties, the ordered structure is typically enhanced or the participation of glycerol is increased. However, this can restrict the migration of quaternary ammonium salts in the interlayer region and weaken interfacial contact. Conversely, to improve antibacterial activity and onset speed, the proportion of free quaternary ammonium salts is often increased, but this can easily disturb interlayer hydration and interfacial balance, leading to viscosity fluctuations, increased gel particles, and a higher risk of delamination. This invention mitigates both types of side effects through interlayer distribution control, proportion matching, and pH adjustment, achieving a simultaneous balance between structural stability, processing flow, and antibacterial function.

[0024] This invention also discloses a method for preparing a quaternary ammonium salt compound antibacterial detergent, comprising the following steps:

[0025] S1. Provides a pre-prepared quaternary ammonium salt intercalated layered liquid crystal intermediate;

[0026] S2. Add citric acid and deionized water to the quaternary ammonium salt intercalated layered liquid crystal intermediate, wherein the amount of deionized water added is such that the total amount of the resulting product is 1000 parts by weight; mix at 20-35°C for 15-30 minutes, and filter through a 100-200 mesh filter to make the pH value of the resulting product 5.5-6.8, thereby obtaining the quaternary ammonium salt compound antibacterial detergent of claim 1.

[0027] Furthermore, the pH value described in step S2 is measured at 25°C.

[0028] Furthermore, in step S2, when the pH value of the system is higher than 6.8, a citric acid aqueous solution with a mass fraction of 5-30 wt% is added; when the pH value of the system is lower than 5.5, a sodium bicarbonate aqueous solution is added until the pH value is 5.5-6.8.

[0029] Furthermore, in step S2, the amount of citric acid added is 0.5-2.5 parts by weight, and the amount of deionized water added is 855.2-859.0 parts by weight, so that the total amount of the resulting product is 1000 parts by weight.

[0030] Furthermore, the filtration in step S2 is used to remove undissolved solids or gel particles.

[0031] Furthermore, the pH value of the quaternary ammonium salt compound antibacterial detergent obtained in step S2 is 5.8-6.5; the glycerol content is 1.5-3.0 parts by weight based on 100 parts by weight of the total amount of the obtained quaternary ammonium salt compound antibacterial detergent; and it is filled after standing at 20-30℃ for 12-24 hours.

[0032] Furthermore, the crude esterified product of laurate dodecyl glucoside is an esterified product obtained by esterification of dodecyl glucoside and laurate, including monoester components, polyester components and incompletely esterified dodecyl glucoside components.

[0033] Furthermore, the layered liquid crystal phase was characterized by small-angle X-ray scattering and polarizing microscopy, and the interlayer spacing was calculated based on the characteristic peaks of small-angle X-ray scattering.

[0034] Furthermore, the distribution of benzalkonium chloride and dicedyldimethylammonium chloride in the interlayer region of the layered liquid crystal phase was characterized by changes in small-angle X-ray scattering characteristic peaks, Fourier transform infrared spectroscopy, or cryo-transmission electron microscopy.

[0035] Furthermore, step A2 is carried out under reduced pressure continuous dehydration conditions, and a condenser reflux device and mechanical stirring are used.

[0036] Furthermore, sodium bicarbonate in step A4 is added in the form of an aqueous solution with a mass fraction of 5-10 wt%, the pH value in step A4 is measured at 25°C, and the filtration is used to remove the salt solids formed after neutralization.

[0037] Furthermore, the pH values ​​in steps D3 and S4 were measured at 25°C. When the pH value of the system was higher than 6.8, a citric acid aqueous solution with a mass fraction of 5-30 wt% was added. When the pH value of the system was lower than 5.5, a sodium bicarbonate aqueous solution was added until the pH value was 5.5-6.8.

[0038] Furthermore, the filtration in step D2 is used to remove undissolved solids or gel particles.

[0039] Furthermore, when benzalkonium chloride and dicedyldimethylammonium chloride are commercial raw materials, their addition amount is calculated based on the effective quaternary ammonium salt content.

[0040] As another aspect of this invention, a preparation method is employed that first prepares a layered liquid crystal intermediate, then performs quaternary ammonium salt intercalation, and finally adds citric acid and deionized water to adjust the pH value. This method is primarily used to achieve, fix, or amplify the aforementioned synergistic effects. In existing technologies, adding the quaternary ammonium salt, acid, and all water at once simplifies the process, but it can easily lead to interfacial competition and interlayer hydration imbalance before the liquid crystal structure is established, making it difficult to stabilize the layered liquid crystal phase and affecting filtration and filling. Excessive pursuit of structural treatment may reduce the system's fluidity and limit its free activity. This invention, through process sequence control, post-intercalation pH adjustment, and terminal filtration coupling, simultaneously stabilizes the interlayer region distribution, system uniformity, and processing window, thereby continuously maintaining the product's structural stability, antibacterial effect, and mild usage characteristics.

[0041] The lamellar liquid crystal phase, composed of crude esterified dodecyl glucoside, dodecyl glucoside, and glycerol, primarily serves to stabilize the structure, ensure uniform storage, and establish a filtration and filling window. The benzalkonium chloride and dicedyldimethylammonium chloride complex system mainly provides antibacterial properties. If the former system alone constitutes a high proportion, while it promotes a more ordered lamellar liquid crystal phase, it can lead to increased interlayer constraint, restricted quaternary ammonium salt migration, and insufficient interfacial contact. Conversely, if the latter system alone constitutes a high proportion, while it enhances antibacterial activity, it can disrupt interlayer hydration and interfacial balance, resulting in viscosity fluctuations, increased gel particles, and decreased stability. This invention, through interlayer region distribution, proportion matching, and stepwise intercalation, allows the two types of components to mutually correct each other within the same system, ultimately achieving a balance between structural stability, processing compatibility, and antibacterial performance.

[0042] Beneficial technical effects

[0043] 1. This invention constructs a layered liquid crystal phase using crude esterified product of dodecyl glucoside, dodecyl glucoside, glycerol, and deionized water, and distributes benzalkonium chloride and dicedyldimethylammonium chloride in the interlayer region, which is beneficial to maintaining the stability and storage homogeneity of the layered liquid crystal phase of the system, and reducing viscosity fluctuations, increased gel particles, and the risk of delamination caused by local aggregation of active components.

[0044] 2. This invention does not rely on simply increasing the proportion of free quaternary ammonium salts to obtain antibacterial properties. Instead, it balances activity and interface stability through interlayer region distribution and proportion matching. This improves the system's ability to balance antibacterial properties and a wide processing window while maintaining filtration and filling stability and processing flowability.

[0045] 3. This invention utilizes the synergistic effect of glycerol and the lamellar liquid crystal phase to establish a water-retaining and slow-release interface. Without significantly sacrificing fluidity, it helps to maintain mild moisturizing and low-irritation characteristics, and reduces the problem of decreased mildness caused by excessive dilution of the system or an increase in the proportion of free surfactants.

[0046] 4. The preparation method of the present invention first forms a layered liquid crystal intermediate, then performs quaternary ammonium salt intercalation, and subsequently adjusts the pH value and filters. The process sequence is clear, which makes it easy to obtain products with consistent structural state in a stable manner. It is also beneficial to connect filtration, settling and filling in the scale-up production, and improves the process repeatability and industrial adaptability. Attached Figure Description

[0047] Figure 1 Small-angle X-ray scattering curves of the layered liquid crystal phases in Example 1, Comparative Example 1, and Comparative Example 10 are shown.

[0048] Figure 2 The Fourier transform infrared absorbance spectra of Example 1, Comparative Example 3, and Comparative Example 10 are shown.

[0049] Figure 3 The N 1s high-resolution X-ray photoelectron spectra of Example 1, Comparative Example 8, and Comparative Example 9 are shown.

[0050] Figure 4 The diagram shows the bactericidal kinetics curves for Example 1, Comparative Example 8, and Comparative Example 9.

[0051] Figure 5 The cumulative transmittance curves of Franz diffusion for Example 1, Comparative Example 10, and Comparative Example 7 are shown.

[0052] Figure 6 The figures show the Franz diffusion flux curves for Example 1, Comparative Example 10, and Comparative Example 7.

[0053] Figure 7 The rheological flow curves are for Example 1, Comparative Example 6, and Comparative Example 10.

[0054] Figure 8 The structural recovery curves are for Example 1, Comparative Example 6, and Comparative Example 10.

[0055] Figure 9 Macroscopic photograph of the quaternary ammonium salt compound antibacterial detergent prepared in Example 1.

[0056] Figure 10 This is a cryo-transmission electron micrograph of the quaternary ammonium salt compound antibacterial detergent prepared in Example 1, wherein... Figure 10 (a) is a low-magnification topography image. Figure 10 (b) is a diagram of a mesoploid layered structure. Figure 10 (c) is a high-magnification diagram of the head group region of the bilayer. Figure 10 (d) is the selected area electron diffraction pattern. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0058] Example 1

[0059] A method for preparing a quaternary ammonium salt compound antibacterial detergent includes the following steps:

[0060] Step A: Preparation of crude laurate dodecyl glucoside esterified product

[0061] A1. Mix 100 parts by weight of dodecyl glucoside, 20 parts by weight of lauric acid, and 0.2 parts by weight of p-toluenesulfonic acid monohydrate relative to 100 parts by weight of dodecyl glucoside in this embodiment.

[0062] A2. The reaction was carried out at 110℃ for 2 hours under nitrogen protection, and the water generated in the reaction was removed under a pressure of 0.005MPa. The dehydration was carried out under reduced pressure and continuous dehydration conditions, and a reflux condenser and mechanical stirring were used.

[0063] A3. The esterification reaction ends when the acid value of the reaction system drops to 15 mg KOH / g.

[0064] A4. Add 0.5 parts by weight of sodium bicarbonate relative to 100 parts by weight of dodecyl glucoside in step A1, in the form of a 5 wt% aqueous solution, and neutralize to a pH of 6.0. In this embodiment, the pH value was measured at 25°C. Filter to remove the salt solids formed after neutralization, obtaining the crude esterified product of dodecyl glucoside laurate of this embodiment. The crude esterified product of dodecyl glucoside laurate prepared in this embodiment is an esterification product obtained by esterification of dodecyl glucoside with laurate, including monoester components, polyester components, and incompletely esterified dodecyl glucoside components.

[0065] Step B: Forming a layered liquid crystal intermediate

[0066] B1. Mix 5 parts by weight of the crude esterified product of laurate dodecyl glucoside obtained in this embodiment, 15 parts by weight of dodecyl glucoside, 10 parts by weight of glycerol and 110 parts by weight of deionized water to make the total amount of the mixture 140 parts by weight.

[0067] B2. Stir at 200 rpm for 20 minutes at 50°C.

[0068] B3. Let stand at 20℃ for 8 hours.

[0069] B4. A layered liquid crystal intermediate with an interlayer spacing of 4.0 nm was obtained in this embodiment. The layered liquid crystal intermediate in this embodiment was characterized by small-angle X-ray scattering and polarizing microscopy. The interlayer spacing was calculated based on the characteristic peaks of small-angle X-ray scattering.

[0070] Step C: Preparation of quaternary ammonium salt intercalated layered liquid crystal intermediates

[0071] C1. Take 140 parts by weight of the layered liquid crystal intermediate of this embodiment, add 0.3 parts by weight of benzalkonium chloride and 0.2 parts by weight of diecrystaldimethylammonium chloride. In this embodiment, when benzalkonium chloride and diecrystaldimethylammonium chloride are commercial raw materials, their addition amount is calculated based on the effective quaternary ammonium salt content.

[0072] C2. Stir at 200 rpm for 10 min at 20°C.

[0073] C3. A quaternary ammonium salt intercalated layered liquid crystal intermediate with an interlayer spacing of 4.0 nm was obtained in this embodiment.

[0074] Step S: Preparation of quaternary ammonium salt compound antibacterial detergent

[0075] S1. Provide 140.5 parts by weight of the prepared quaternary ammonium salt intercalated layered liquid crystal intermediate.

[0076] S2. Add 0.5 parts by weight of citric acid and 859.0 parts by weight of deionized water to the quaternary ammonium salt intercalated layered liquid crystal intermediate of this embodiment. The amount of deionized water added in this embodiment is based on ensuring the total amount of the resulting product is 1000 parts by weight. Mix at 20°C for 15 minutes and filter through a 100-mesh filter. Filtration in this embodiment is used to remove undissolved solids or gel particles, resulting in a pH value of 5.5 for the final product. The pH value in this embodiment is measured at 25°C. When the system pH value is higher than 6.8, add a 5 wt% aqueous solution of citric acid. When the system pH value is lower than 5.5, add an aqueous solution of sodium bicarbonate until the pH value is between 5.5 and 6.8, thus obtaining the quaternary ammonium salt compound antibacterial detergent of this embodiment.

[0077] The quaternary ammonium salt compound antibacterial detergent obtained in this embodiment was filled after standing at 20°C for 12 hours.

[0078] The quaternary ammonium salt compound antibacterial detergent prepared in this embodiment comprises, based on a total composition of 100 parts by weight: 0.50 parts by weight of crude esterified product of dodecyl glucoside laurate, 1.50 parts by weight of dodecyl glucoside, 0.03 parts by weight of benzalkonium chloride, 0.02 parts by weight of decyl dimethyl ammonium chloride, 1.00 parts by weight of glycerol, 0.05 parts by weight of citric acid, and deionized water to make up to 100 parts by weight. The crude esterified product of laurate-dodecyl glucoside is obtained by esterification of dodecyl glucoside and laurate. The detergent in this embodiment contains a layered liquid crystal phase formed by the crude esterified product of laurate-dodecyl glucoside, dodecyl glucoside, glycerol and deionized water. The interlayer spacing of the layered liquid crystal phase in this embodiment is 4.0 nm. The pH value of the detergent in this embodiment is 5.5. In this embodiment, benzalkonium chloride and dicedyldimethylammonium chloride are distributed in the interlayer region of the layered liquid crystal phase. The characteristics are performed by small-angle X-ray scattering characteristic peak changes, Fourier transform infrared spectroscopy or cryo-transmission electron microscopy.

[0079] Features of this embodiment: This embodiment employs a formulation scheme biased towards the low-value range, with both active ingredients and functional additives used at low levels. The esterification reaction is carried out under mild low-temperature and low-pressure conditions. The laminar liquid crystal formation process utilizes low stirring temperature and speed, as well as a short processing time. The resulting product has tightly spaced layers and a slightly acidic pH, forming a mild antibacterial detergent formula. It is suitable for daily cleansing and care for people with sensitive skin, sterilization of infant products, surface cleaning of medical devices, and special scenarios with strict requirements regarding irritation.

[0080] Example 2

[0081] A method for preparing a quaternary ammonium salt compound antibacterial detergent includes the following steps:

[0082] Step A: Preparation of crude laurate dodecyl glucoside esterified product

[0083] A1. Mix 100 parts by weight of dodecyl glucoside, 70 parts by weight of lauric acid, and 2.0 parts by weight of p-toluenesulfonic acid monohydrate relative to 100 parts by weight of dodecyl glucoside in this embodiment.

[0084] A2. The reaction was carried out at 135℃ for 6 hours under nitrogen protection, and the water generated in the reaction was removed under a pressure of 0.020 MPa. The dehydration was carried out under reduced pressure and continuous dehydration conditions, and a reflux condenser and mechanical stirring were used.

[0085] A3. The esterification reaction ends when the acid value of the reaction system drops to 40 mg KOH / g.

[0086] A4. Add 3.0 parts by weight of sodium bicarbonate relative to 100 parts by weight of dodecyl glucoside in step A1, in the form of a 10 wt% aqueous solution, and neutralize to a pH of 7.5. In this embodiment, the pH value was measured at 25°C. Filter to remove the salt solids formed after neutralization, obtaining the crude esterified product of dodecyl glucoside laurate of this embodiment. The crude esterified product of dodecyl glucoside laurate prepared in this embodiment is an esterification product obtained by esterification of dodecyl glucoside with laurate, including monoester components, polyester components, and incompletely esterified dodecyl glucoside components.

[0087] Step B: Forming a layered liquid crystal intermediate

[0088] B1. Mix 30 parts by weight of the crude esterified product of laurate dodecyl glucoside, 60 parts by weight of dodecyl glucoside, 40 parts by weight of glycerol, and 10 parts by weight of deionized water obtained in this embodiment to make a total mixture of 140 parts by weight.

[0089] B2. Stir at 800 rpm for 60 minutes at 65°C.

[0090] B3. Let stand at 30℃ for 24 hours.

[0091] B4. A layered liquid crystal intermediate with an interlayer spacing of 9.0 nm was obtained in this embodiment. The layered liquid crystal intermediate in this embodiment was characterized by small-angle X-ray scattering and polarizing microscopy. The interlayer spacing was calculated based on the characteristic peaks of small-angle X-ray scattering.

[0092] Step C: Preparation of quaternary ammonium salt intercalated layered liquid crystal intermediates

[0093] C1. Take 140 parts by weight of the layered liquid crystal intermediate of this embodiment, add 1.5 parts by weight of benzalkonium chloride and 0.8 parts by weight of diecrystaldimethylammonium chloride. In this embodiment, when benzalkonium chloride and diecrystaldimethylammonium chloride are commercial raw materials, their addition amount is calculated based on the effective quaternary ammonium salt content.

[0094] C2. Stir at 800 rpm for 30 minutes at 35°C.

[0095] C3. A quaternary ammonium salt intercalated layered liquid crystal intermediate with an interlayer spacing of 9.0 nm was obtained in this embodiment.

[0096] Step S: Preparation of quaternary ammonium salt compound antibacterial detergent

[0097] S1. Provide 142.3 parts by weight of the prepared quaternary ammonium salt intercalated layered liquid crystal intermediate.

[0098] S2. Add 2.5 parts by weight of citric acid and 855.2 parts by weight of deionized water to the quaternary ammonium salt intercalated layered liquid crystal intermediate of this embodiment. The amount of deionized water added in this embodiment is based on ensuring the total amount of the resulting product is 1000 parts by weight. Mix at 35°C for 30 minutes and filter through a 200-mesh filter. Filtration in this embodiment is used to remove undissolved solids or gel particles, resulting in a pH value of 6.8 for the final product. The pH value in this embodiment is measured at 25°C. When the system pH value is higher than 6.8, add a 30 wt% citric acid aqueous solution; when the system pH value is lower than 5.5, add a sodium bicarbonate aqueous solution until the pH value is between 5.5 and 6.8, thus obtaining the quaternary ammonium salt compound antibacterial detergent of this embodiment.

[0099] The quaternary ammonium salt compound antibacterial detergent obtained in this embodiment was filled after being left to stand at 30°C for 24 hours.

[0100] The quaternary ammonium salt compound antibacterial detergent prepared in this embodiment comprises, based on a total composition of 100 parts by weight: 3.00 parts by weight of crude esterified product of dodecyl glucoside laurate, 6.00 parts by weight of dodecyl glucoside, 0.15 parts by weight of benzalkonium chloride, 0.08 parts by weight of decyl dimethyl ammonium chloride, 4.00 parts by weight of glycerol, 0.25 parts by weight of citric acid, and deionized water to make up to 100 parts by weight. The crude esterified product of laurate-dodecyl glucoside is obtained by esterification of dodecyl glucoside and laurate. The detergent in this embodiment contains a layered liquid crystal phase formed by the crude esterified product of laurate-dodecyl glucoside, dodecyl glucoside, glycerol and deionized water. The interlayer spacing of the layered liquid crystal phase in this embodiment is 9.0 nm. The pH value of the detergent in this embodiment is 6.8. In this embodiment, benzalkonium chloride and dicedyldimethylammonium chloride are distributed in the interlayer region of the layered liquid crystal phase. The characteristics are performed by small-angle X-ray scattering characteristic peak changes, Fourier transform infrared spectroscopy or cryo-transmission electron microscopy.

[0101] Features of this embodiment: This embodiment employs a formulation strategy targeting the high-value range of active ingredients, with high levels of both active ingredients and functional additives. The esterification reaction is enhanced under high temperature and high pressure conditions. The lamellar liquid crystal formation process utilizes high stirring temperature and speed, along with a longer processing time. The resulting product exhibits expanded interlayer spacing and a near-neutral pH, forming a highly effective antibacterial detergent formula. It is suitable for deep cleaning in heavily polluted environments, surface sterilization of industrial equipment, disinfection of food processing workshops, and other professional scenarios requiring stringent antibacterial effects.

[0102] Example 3

[0103] A method for preparing a quaternary ammonium salt compound antibacterial detergent includes the following steps:

[0104] Step A: Preparation of crude laurate dodecyl glucoside esterified product

[0105] A1. Mix 100 parts by weight of dodecyl glucoside, 45 parts by weight of lauric acid, and 1.1 parts by weight of p-toluenesulfonic acid monohydrate relative to 100 parts by weight of dodecyl glucoside in this embodiment.

[0106] A2. The reaction was carried out at 122.5℃ for 4 hours under nitrogen protection, and the water generated in the reaction was removed under a pressure of 0.0125MPa. The dehydration was carried out under reduced pressure and continuous dehydration conditions, and a reflux condenser and mechanical stirring were used.

[0107] A3. The esterification reaction ends when the acid value of the reaction system drops to 27.5 mg KOH / g.

[0108] A4. Add 1.75 parts by weight of sodium bicarbonate relative to 100 parts by weight of dodecyl glucoside in step A1, in the form of a 7.5 wt% aqueous solution, and neutralize to a pH of 6.75. In this embodiment, the pH value was measured at 25°C. Filter to remove the salt solids formed after neutralization, obtaining the crude esterified product of dodecyl glucoside laurate of this embodiment. The crude esterified product of dodecyl glucoside laurate prepared in this embodiment is an esterification product obtained by esterification of dodecyl glucoside with laurate, including monoester components, polyester components, and incompletely esterified dodecyl glucoside components.

[0109] Step B: Forming a layered liquid crystal intermediate

[0110] B1. Mix 17.5 parts by weight of the crude esterified product of laurate dodecyl glucoside obtained in this embodiment, 37.5 parts by weight of dodecyl glucoside, 15 parts by weight of glycerol and 70 parts by weight of deionized water to make the total amount of the mixture 140 parts by weight.

[0111] B2. Stir at 500 rpm for 40 minutes at 57.5℃.

[0112] B3. Let stand at 25℃ for 16 hours.

[0113] B4. A layered liquid crystal intermediate with an interlayer spacing of 6.5 nm was obtained in this embodiment. The layered liquid crystal intermediate in this embodiment was characterized by small-angle X-ray scattering and polarizing microscopy. The interlayer spacing was calculated based on the characteristic peaks of small-angle X-ray scattering.

[0114] Step C: Preparation of quaternary ammonium salt intercalated layered liquid crystal intermediates

[0115] C1. Take 140 parts by weight of the layered liquid crystal intermediate of this embodiment, add 0.9 parts by weight of benzalkonium chloride and 0.5 parts by weight of diecrystaldimethylammonium chloride. In this embodiment, when benzalkonium chloride and diecrystaldimethylammonium chloride are commercial raw materials, their addition amount is calculated based on the effective quaternary ammonium salt content.

[0116] C2. Stir at 500 rpm for 20 min at 27.5℃.

[0117] C3. A quaternary ammonium salt intercalated layered liquid crystal intermediate with an interlayer spacing of 6.5 nm was obtained in this embodiment.

[0118] Step S: Preparation of quaternary ammonium salt compound antibacterial detergent

[0119] S1. Provide 141.4 parts by weight of the prepared quaternary ammonium salt intercalated layered liquid crystal intermediate.

[0120] S2. Add 1.5 parts by weight of citric acid and 857.1 parts by weight of deionized water to the quaternary ammonium salt intercalated layered liquid crystal intermediate of this embodiment. The amount of deionized water added in this embodiment is based on ensuring the total amount of the resulting product is 1000 parts by weight. Mix at 27.5°C for 22.5 minutes and filter through a 150-mesh filter. Filtration in this embodiment is used to remove undissolved solids or gel particles, resulting in a pH value of 5.8 for the final product. The pH value in this embodiment is measured at 25°C. When the system pH value is higher than 6.8, add a 17.5 wt% aqueous solution of citric acid. When the system pH value is lower than 5.5, add an aqueous solution of sodium bicarbonate until the pH value is between 5.5 and 6.8, thus obtaining the quaternary ammonium salt compound antibacterial detergent of this embodiment.

[0121] The pH value of the quaternary ammonium salt compound antibacterial detergent obtained in this embodiment is 5.8. Based on 100 parts by weight of the total amount of the obtained quaternary ammonium salt compound antibacterial detergent, the glycerin content is 1.5 parts by weight. After standing at 25°C for 18 hours, it is filled.

[0122] The quaternary ammonium salt compound antibacterial detergent prepared in this embodiment comprises, based on a total composition of 100 parts by weight: 1.75 parts by weight of crude laurate dodecyl glucoside esterification product, 3.75 parts by weight of dodecyl glucoside, 0.09 parts by weight of benzalkonium chloride, 0.05 parts by weight of diecrystal dimethyl ammonium chloride, 1.50 parts by weight of glycerin, 0.15 parts by weight of citric acid, and deionized water to make up to 100 parts by weight. The crude esterified product of laurate-dodecyl glucoside is obtained by esterification of dodecyl glucoside and laurate. The detergent in this embodiment contains a layered liquid crystal phase formed by the crude esterified product of laurate-dodecyl glucoside, dodecyl glucoside, glycerol and deionized water. The interlayer spacing of the layered liquid crystal phase in this embodiment is 6.5 nm. The pH value of the detergent in this embodiment is 5.8. In this embodiment, benzalkonium chloride and dicedyldimethylammonium chloride are distributed in the interlayer region of the layered liquid crystal phase. The characteristics are performed by small-angle X-ray scattering characteristic peak changes, Fourier transform infrared spectroscopy or cryo-transmission electron microscopy.

[0123] Features of this embodiment: This embodiment employs a moderate formulation design, with balanced amounts of each component, appropriate esterification reaction process parameters, moderate temperature and stirring conditions during the lamellar liquid crystal formation process, a glycerol content at a lower level within the preferred range, and a pH value in the slightly acidic region within the preferred range. The resulting product has moderate interlayer spacing, forming a balanced antibacterial detergent formula. It is suitable for daily household cleaning and disinfection, washing of tableware, surface cleaning in public places, and other general applications requiring both mildness and antibacterial properties.

[0124] Example 4

[0125] A method for preparing a quaternary ammonium salt compound antibacterial detergent includes the following steps:

[0126] Step A: Preparation of crude laurate dodecyl glucoside esterified product

[0127] A1. Mix 100 parts by weight of dodecyl glucoside, 58 parts by weight of lauric acid, and 1.6 parts by weight of p-toluenesulfonic acid monohydrate relative to 100 parts by weight of dodecyl glucoside in this embodiment.

[0128] A2. The reaction was carried out at 128°C for 5 hours under nitrogen protection, and the water generated in the reaction was removed under a pressure of 0.016 MPa. The dehydration was carried out under reduced pressure and continuous dehydration conditions, and a reflux condenser and mechanical stirring were used.

[0129] A3. The esterification reaction ends when the acid value of the reaction system drops to 34 mg KOH / g.

[0130] A4. Add 2.4 parts by weight of sodium bicarbonate relative to 100 parts by weight of dodecyl glucoside in step A1, in the form of a 9 wt% aqueous solution, and neutralize to a pH of 7.2. In this embodiment, the pH value was measured at 25°C. Filter to remove the salt solids formed after neutralization, obtaining the crude esterified product of dodecyl glucoside laurate of this embodiment. The crude esterified product of dodecyl glucoside laurate prepared in this embodiment is an esterification product obtained by esterification of dodecyl glucoside with laurate, including monoester components, polyester components, and incompletely esterified dodecyl glucoside components.

[0131] Step B: Forming a layered liquid crystal intermediate

[0132] B1. Mix 22.5 parts by weight of the crude esterified product of laurate dodecyl glucoside obtained in this embodiment, 48 parts by weight of dodecyl glucoside, 30 parts by weight of glycerol and 39.5 parts by weight of deionized water to make a total mixture of 140 parts by weight.

[0133] B2. Stir at 700 rpm for 52 minutes at 61°C.

[0134] B3. Let stand at 28℃ for 21 hours.

[0135] B4. A layered liquid crystal intermediate with an interlayer spacing of 7.8 nm was obtained in this embodiment. The layered liquid crystal intermediate in this embodiment was characterized by small-angle X-ray scattering and polarizing microscopy. The interlayer spacing was calculated based on the characteristic peaks of small-angle X-ray scattering.

[0136] Step C: Preparation of quaternary ammonium salt intercalated layered liquid crystal intermediates

[0137] C1. Take 140 parts by weight of the layered liquid crystal intermediate of this embodiment, add 1.2 parts by weight of benzalkonium chloride and 0.6 parts by weight of diecrystaldimethylammonium chloride. In this embodiment, when benzalkonium chloride and diecrystaldimethylammonium chloride are commercial raw materials, their addition amount is calculated based on the effective quaternary ammonium salt content.

[0138] C2. Stir at 700 rpm for 26 minutes at 32°C.

[0139] C3. A quaternary ammonium salt intercalated layered liquid crystal intermediate with an interlayer spacing of 7.8 nm was obtained in this embodiment.

[0140] Step S: Preparation of quaternary ammonium salt compound antibacterial detergent

[0141] S1. Provide 141.8 parts by weight of the prepared quaternary ammonium salt intercalated layered liquid crystal intermediate.

[0142] S2. Add 2.0 parts by weight of citric acid and 856.2 parts by weight of deionized water to the quaternary ammonium salt intercalated layered liquid crystal intermediate of this embodiment. The amount of deionized water added in this embodiment is based on ensuring the total amount of the resulting product is 1000 parts by weight. Mix at 32°C for 27 minutes and filter through a 180-mesh filter. Filtration in this embodiment is used to remove undissolved solids or gel particles, resulting in a pH value of 6.5 for the final product. The pH value in this embodiment is measured at 25°C. When the system pH value is higher than 6.8, add a 25 wt% citric acid aqueous solution; when the system pH value is lower than 5.5, add a sodium bicarbonate aqueous solution until the pH value is between 5.5 and 6.8, thus obtaining the quaternary ammonium salt compound antibacterial detergent of this embodiment.

[0143] The pH value of the quaternary ammonium salt compound antibacterial detergent obtained in this embodiment is 6.5. Based on 100 parts by weight of the total amount of the obtained quaternary ammonium salt compound antibacterial detergent, the glycerin content is 3.0 parts by weight. It is filled after standing at 28°C for 21 hours.

[0144] The quaternary ammonium salt compound antibacterial detergent prepared in this embodiment comprises, based on a total composition of 100 parts by weight: 2.25 parts by weight of crude laurate dodecyl glucoside esterification product, 4.80 parts by weight of dodecyl glucoside, 0.12 parts by weight of benzalkonium chloride, 0.06 parts by weight of diecrystal dimethyl ammonium chloride, 3.00 parts by weight of glycerol, 0.20 parts by weight of citric acid, and deionized water to make up to 100 parts by weight. The crude esterified product of laurate-dodecyl glucoside is obtained by esterification of dodecyl glucoside and laurate. The detergent in this embodiment contains a layered liquid crystal phase formed by the crude esterified product of laurate-dodecyl glucoside, dodecyl glucoside, glycerol and deionized water. The interlayer spacing of the layered liquid crystal phase in this embodiment is 7.8 nm. The pH value of the detergent in this embodiment is 6.5. In this embodiment, benzalkonium chloride and dicedyldimethylammonium chloride are distributed in the interlayer region of the layered liquid crystal phase. The characteristics are performed by small-angle X-ray scattering characteristic peak changes, Fourier transform infrared spectroscopy or cryo-transmission electron microscopy.

[0145] Features of this embodiment: This embodiment employs a moderately high formulation strategy, resulting in a high but moderate content of active ingredients. The esterification reaction process parameters are biased towards enhanced conditions, and the lamellar liquid crystal formation process utilizes higher temperatures and stronger stirring conditions. The glycerol content is at a high level within the preferred range, and the pH value is in the near-neutral region within the preferred range. The resulting product has a wider interlayer spacing, forming a strengthened antibacterial detergent formula. It is suitable for commercial laundry services, hotel and guesthouse cleaning and disinfection, maintenance of public areas in schools and hospitals, and other mid-to-high-end applications requiring both high cleaning effectiveness and long-lasting antibacterial properties.

[0146] Comparative Example 1: Basically the same as Example 1, except that in step B1, the crude product of laurate dodecyl glucoside esterification was changed from 5 parts by weight to 3 parts by weight, and the deionized water was changed from 110 parts by weight to 112 parts by weight to keep the total amount of the mixture at 140 parts by weight, while other conditions remained unchanged.

[0147] Comparative Example 2: It is basically the same as Example 1, except that in step B1, the dodecyl glucoside is changed from 15 parts by weight to 12 parts by weight, and the deionized water is changed from 110 parts by weight to 113 parts by weight to keep the total amount of the mixture at 140 parts by weight, while other conditions remain unchanged.

[0148] Comparative Example 3: It is basically the same as Example 1, except that in step B1, the glycerol is changed from 10 parts by weight to 8 parts by weight, and the deionized water is changed from 110 parts by weight to 112 parts by weight to keep the total amount of the mixture at 140 parts by weight, while other conditions remain unchanged.

[0149] Comparative Example 4: It is basically the same as Example 1, except that the amount of benzalkonium chloride added in step C1 is changed from 0.3 parts by weight to 0.2 parts by weight, while other conditions remain unchanged.

[0150] Comparative Example 5: It is basically the same as Example 1, except that the amount of diecryldimethylammonium chloride added in step C1 is changed from 0.2 parts by weight to 0.1 parts by weight, while other conditions remain unchanged.

[0151] Comparative Example 6: It is basically the same as Example 1, except that the stirring temperature in step B2 is changed from 50°C to 45°C, while other conditions remain unchanged.

[0152] Comparative Example 7: It is basically the same as Example 1, except that in step S2, a 5 wt% citric acid aqueous solution is used to adjust the pH of the system to 5.2, and the amount of deionized water added is reduced accordingly to keep the total amount of the obtained product at 1000 parts by weight, while other conditions remain unchanged.

[0153] Comparative Example 8: Essentially the same as Example 1, except that benzalkonium chloride was not added in step C1, and only 0.2 parts by weight of dialc-dimethylammonium chloride was added; step S1 provided 140.2 parts by weight of the quaternary ammonium salt intercalated layered liquid crystal intermediate; and in step S2, 0.5 parts by weight of citric acid and 859.3 parts by weight of deionized water were added to bring the total amount of the resulting product to 1000 parts by weight, with other conditions remaining unchanged. This comparative example was used to verify the synergistic effect of benzalkonium chloride and dialc-dimethylammonium chloride.

[0154] Comparative Example 9: Essentially the same as Example 1, except that in step C1, decyl dimethyl ammonium chloride was not added; only 0.3 parts by weight of benzalkonium chloride was added. Step S1 provided 140.3 parts by weight of the quaternary ammonium salt intercalated layered liquid crystal intermediate. In step S2, 0.5 parts by weight of citric acid and 859.2 parts by weight of deionized water were added to bring the total amount of the resulting product to 1000 parts by weight. Other conditions remained unchanged. This comparative example was used to verify the synergistic effect of benzalkonium chloride and decyl dimethyl ammonium chloride.

[0155] Comparative Example 10: Essentially the same as Example 1, except that the order of "first forming a laminar liquid crystal intermediate, then performing quaternary ammonium salt intercalation" is omitted. In step B1, the amount of deionized water is changed from 110 parts by weight to 109.5 parts by weight, and 0.3 parts by weight of benzalkonium chloride and 0.2 parts by weight of disedecyldimethylammonium chloride are added simultaneously, bringing the total mixture to 140 parts by weight. Subsequently, the process is performed according to steps B2 and B3 of Example 1, without executing steps C1 and C2. Step S1 provides 140.0 parts by weight of the intermediate, and in step S2, 0.5 parts by weight of citric acid and 859.5 parts by weight of deionized water are added to bring the total amount of the resulting product to 1000 parts by weight, with other conditions remaining unchanged. This comparative example is used to verify the synergistic effect of first constructing the laminar liquid crystal and then intercalating it.

[0156] Performance testing:

[0157] After the finished product was equilibrated at 25℃ for 30 minutes, the pH value was directly measured using the glass electrode method to confirm whether the pH of the finished product was within the 5.5-6.8 window and to provide basic parameters for mildness analysis. The pH meter was calibrated with standard buffer solution, and the test was performed in triplicate. According to GB / T 6368-2008 standard, the results are expressed as mean ± standard deviation, and it was determined whether they fell within the target range.

[0158] After equilibration at 25°C for 24 hours, the laminar liquid crystal intermediate and the finished thin-layer sample were subjected to small-angle X-ray scattering (SAXS) scanning, and the texture was simultaneously recorded using polarized light microscopy to determine the interlayer spacing and degree of order of the laminar liquid crystal phases. The positions of the SAXS characteristic peaks were determined according to... Interlayer spacing was calculated, and birefringent texture was determined using polarizing microscopy. Data acquisition was performed according to ISO 17867:2020 standard, with the q range set to 0.2-3.0 nm. The test was repeated 3 times, and the interlayer spacing, peak half-width, and peak intensity ratio were output.

[0159] Lyophilized membrane samples were analyzed using ATR-FTIR at 4000-650 cm⁻¹. Within a certain range, tests were conducted to verify hydrogen bonding / ion association and changes in the interlayer chemical environment of quaternary ammonium salts. The shifts of characteristic absorption peaks such as OH, C–O–C, and C–N reflect the strength of interfacial interactions; analysis was performed by comparing peak position, peak shape, and area ratio. Following ASTM E1252-98(2021) standard, the spectral resolution was set to 4 cm⁻¹. Scan 32 times, test repeated 3 times, and give the characteristic peak positions. And peak area ratio.

[0160] The finished diluted solution was evaluated for antibacterial activity and onset rate using Escherichia coli and Staphylococcus aureus as indicator bacteria, employing a quantitative suspension sterilization method. The initial bacterial concentration was controlled at [value missing]. - CFU / mL was used, and the reaction was carried out at 25℃ for 1 min and 5 min respectively. After the reaction was terminated by adding a neutralizing agent, viable bacteria were counted. The test was repeated 3 times according to GB / T 38502-2020 standard. The logarithmic kill value was calculated by the change in viable bacteria count before and after the reaction, and the kill rate and logarithmic kill value were output.

[0161] After the finished product was left to stand at 25℃ for 24 hours, it was pre-shorn, and the results were measured using a rotational viscometer at 0.5→50→0.5 s. The program scans to evaluate the low-viscosity processing window and structural recovery capability. Apparent viscosity, shear thinning, and thixotropic recovery characteristics are obtained at different shear rates. Following ASTM D2196-20, the test is repeated three times, with each test outputting 10 seconds. Apparent viscosity, thixotropic hysteresis loop area, and 1-minute recovery rate.

[0162] The filled finished product was stored at 45℃ for 30 days, subjected to three freeze-thaw cycles, and centrifuged at 3000 r / min for 30 min according to the reference protocol. The flux and residue were then tested through a 100-mesh filter to evaluate storage homogeneity, gel particle size, and filtration filling stability. Accelerated heat storage, freeze-thaw cycles, and centrifugation can amplify structural instability, and filtration resistance reflects the tendency of particles / gel to clog the filter. A stability protocol was established according to ISO / TR 18811:2018, with tests repeated three times, outputting stratification rate, residue amount, and filtration flux.

[0163] The finished product was used to reconstruct a human epidermal lesion (RhE) model according to OECD TG 439 standards. The samples were exposed to the RhE model for 15 min, rinsed, and cultured for 42 h. The absorbance at 570 nm was measured to evaluate low irritation. In the RhE model, cells were reduced to form formazan by MTT, and the absorbance reflected cell viability. The test was repeated three times, with both positive and negative controls provided. Cell viability was output, and irritation was graded.

[0164] The benzalkonium chloride and disedecyldimethylammonium chloride in the finished product were administered using a Franz diffusion cell according to OECD TG 428 standards, with porcine ear skin or human explant skin as a barrier, at a dosage of 10 μL / cm². The sample was diffused at 32°C for 24 hours. The cumulative permeate and steady-state flux of the quaternary ammonium salt in the acceptor solution were quantified by HPLC to evaluate the migration of free radicals and the tendency for transdermal exposure. The test was repeated three times, and the cumulative permeate, steady-state flux, and hysteresis time were output.

[0165] Figure 1 The small-angle X-ray scattering (SAXS) curves of the layered liquid crystal phases of Example 1, Comparative Example 1, and Comparative Example 10 are shown. The layered liquid crystal structure of different samples was characterized by SAXS. Example 1 still showed a clear main scattering peak under low-dose conditions, corresponding to an interlayer spacing of 4.0 nm. However, the peak intensity of Comparative Example 1 and Comparative Example 10 was weakened and the peak shape was broadened. This indicates that reducing the core building blocks or disrupting the pre-phase formation and subsequent intercalation sequence will weaken the orderly layered stacking, proving that the system can form a relatively stable layered liquid crystal phase.

[0166] Figure 2 The Fourier transform infrared absorbance spectra of Example 1, Comparative Example 3, and Comparative Example 10 are shown. Fourier transform infrared spectroscopy was used to analyze the interlayer interface interaction. Example 1 showed more obvious peak shifts and band changes in the hydroxyl stretching vibration region and the ether bond related feature region, indicating that glycerol hydration and intermolecular hydrogen bonding were more complete. In contrast, the related features of Comparative Example 3 and Comparative Example 10 were weakened, indicating that the synergistic and sequential construction of interfacial hydrogen bonds plays an important role in the stable formation of the layered liquid crystal phase.

[0167] Figure 3The N 1s high-resolution X-ray photoelectron spectra of Examples 1, 8, and 9 are shown. X-ray photoelectron spectroscopy was used to characterize the interfacial chemical environment after the intercalation of the two quaternary ammonium salts. The N 1s peak position and peak area characteristics of Example 1 show a more complete quaternary ammonium nitrogen chemical environment. The peak shape and peak area of ​​Comparative Examples 8 and 9 changed after removing one quaternary ammonium salt, respectively, indicating that benzalkonium chloride and decyl dimethyl ammonium chloride do not simply exist side by side, but rather participate together in the interlayer complex intercalation.

[0168] Figure 4 The diagram shows the bactericidal kinetic curves of Example 1, Comparative Example 8, and Comparative Example 9. The bactericidal effect was evaluated by the change in logarithmic kill value over time. Example 1 achieved a higher logarithmic kill value in a short time, with a faster overall onset and a higher final bactericidal level. In contrast, the kinetics of Comparative Example 8 and Comparative Example 9 slowed down significantly after the removal of the single quaternary ammonium salt, indicating that the intercalation of the dual quaternary ammonium salt combination helps to improve the antibacterial onset rate and sustained killing ability.

[0169] Figure 5 The Franz diffusion cumulative permeation curves for Example 1, Comparative Example 10, and Comparative Example 7 are shown. The cumulative permeation behavior of different samples was characterized using a Franz diffusion cell. Example 1 showed a lower cumulative permeation amount and a more gradual increase within the same time period, indicating a lower trend of transmembrane exposure. In contrast, the cumulative permeation amounts of Comparative Example 10 and Comparative Example 7 increased more rapidly, suggesting that the process sequence of first constructing the layered liquid crystal and then performing quaternary ammonium salt intercalation is beneficial for controlling the release and migration behavior of active ingredients.

[0170] Figure 6 The Franz diffusion flux curves for Example 1, Comparative Example 10, and Comparative Example 7 are shown. The instantaneous flux changes of different samples during the permeation process were further analyzed using a Franz diffusion cell. The flux peak of Example 1 was lower and the overall fluctuation was more stable, indicating that its release process was more gentle and controllable. The flux increase of Comparative Example 10 was more obvious, and Comparative Example 7 also showed a relatively large release driving force, indicating that the process sequence and the release environment of the finished product jointly affect the exposure level of the active component.

[0171] Figure 7 The rheological flow curves of Example 1, Comparative Example 6, and Comparative Example 10 are shown. The apparent viscosity of the samples at different shear rates was characterized by rheological testing. Example 1 maintained a high viscosity in the low to medium shear region and exhibited stable shear thinning characteristics, indicating that its internal layered structure was relatively intact. The viscosity of Comparative Example 6 and Comparative Example 10 decreased overall, indicating that weakening the layered liquid crystal formation conditions or disrupting the subsequent intercalation sequence would weaken the network structure and processing stability of the system.

[0172] Figure 8The structural recovery curves of Example 1, Comparative Example 6, and Comparative Example 10 are shown. The structural reconstruction ability of the samples was evaluated by the recovery test after shear failure. Example 1 showed a faster recovery rate and a higher final recovery rate during the recovery process, and showed a better recovery level around 1 minute. In contrast, Comparative Example 6 and Comparative Example 10 had lower recovery rates and recovery degrees. This indicates that forming a lamellar liquid crystal first and then intercalating with quaternary ammonium salt is beneficial to balancing the shear stability and structural recovery ability of the system.

[0173] Figure 9 This is a macroscopic photograph of the quaternary ammonium salt compound antibacterial detergent prepared in Example 1. The sample is a translucent, milky white, homogeneous liquid. No obvious stratification or precipitation is observed when it is still. A faint pearlescent luster can be observed under room temperature light, which is due to the selective scattering of light by the lamellar liquid crystal. The sample has good fluidity, exhibiting typical viscoelastic fluid behavior when the container is tilted. The surface tension is moderate, and a uniform meniscus forms at the edges. The weakly acidic system with a pH of 5.5 gives the sample a slightly watery transparency. Macroscopically, there is no phase separation or flocculation, demonstrating that the lamellar liquid crystal phase system formed by the compounding of crude laurate dodecyl glucoside esterification product and dodecyl glucoside has good macroscopic stability and dispersion uniformity.

[0174] Figure 10 This is a cryo-transmission electron microscope image of the quaternary ammonium salt compound antibacterial detergent prepared in Example 1. Figure 10 (a) Low magnification shows that the sample as a whole exhibits a typical layered liquid crystal dispersion morphology, with liquid crystal domain sizes ranging from 0.5 to 3 μm, and no obvious agglomeration or phase separation. Figure 10 (b) The medium magnification image clearly shows the alternating layered structure. The dark stripes correspond to the polar head group regions of the surfactant bilayer, while the light stripes represent the aqueous layer regions, with a clear interlayer structure. Edge dislocation defects and multilayer vesicle structures with diameters of 200 to 500 nm can be observed in some areas. This is due to the microstructural modulation caused by the intercalation of benzalkonium chloride and disedecyldimethylammonium chloride between the bilayers. Figure 10 (c) Further analysis of the high-magnification image reveals punctate enrichment of quaternary ammonium salts in the head group region of the bilayer. Figure 10 (d) The selected area electron diffraction pattern shows a typical concentric ring diffraction pattern, which proves that the quaternary ammonium salt is distributed in the interlayer region in a non-uniform intercalation manner. This microstructure is conducive to the targeted delivery of antibacterial active components.

[0175] Table 1 Performance of Examples and Comparative Examples

[0176]

[0177] As can be seen from the performance of the examples and comparative examples in Table 1, the overall system of the examples has formed a more stable balance between controllable interlayer spacing, antibacterial effect at 5 minutes, thixotropic recovery, layering control, and low irritation. Among them, Example 3 shows the most balanced comprehensive characteristics, followed by Example 4. Although Example 2 has higher antibacterial activity, it is accompanied by higher viscosity, layering rate, and transdermal permeation, reflecting the structural cost under high load conditions. In each comparative example, reducing the lamellar liquid crystal building components, reducing the liquid crystal formation temperature, lowering the pH, or disrupting the first phase formation and then intercalation sequence all lead to deviation of interlayer spacing, increase in layering rate, or decrease in effective antibacterial effect. Removing any quaternary ammonium salt mainly weakens the effective advantage brought by the combination of 2 quaternary ammonium salts, indicating that the key to the present invention is not the superposition of a single variable, but the synergistic matching of structure, components, and sequence.

[0178] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that any equivalent structural transformations made under the concept of the present invention and using the contents of the specification and drawings of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A quaternary ammonium salt compound antibacterial detergent, characterized in that, Based on a total composition of 100 parts by weight, the composition comprises: 0.50-3.00 parts by weight of crude laurate dodecyl glucoside esterification product, 1.50-6.00 parts by weight of dodecyl glucoside, 0.03-0.15 parts by weight of benzalkonium chloride, 0.02-0.08 parts by weight of diecrystal dimethyl ammonium chloride, 1.00-4.00 parts by weight of glycerol, 0.05-0.25 parts by weight of citric acid, and deionized water to a total of 100 parts by weight; The crude esterified product of laurate-dodecyl glucoside is obtained by esterification of dodecyl glucoside with laurate. The detergent contains a layered liquid crystal phase formed by the crude esterified product of laurate-dodecyl glucoside, dodecyl glucoside, glycerol and deionized water. The interlayer spacing of the layered liquid crystal phase is 4.0-9.0 nm. The pH value of the detergent is 5.5-6.

8. Benzalkonium chloride and dicedyldimethylammonium chloride are distributed in the interlayer region of the layered liquid crystal phase.

2. The quaternary ammonium salt compound antibacterial detergent according to claim 1, characterized in that, The crude product of dodecyl laurate glucoside esterification is prepared by the following steps: A1. Mix 100 parts by weight of dodecyl glucoside, 20-70 parts by weight of lauric acid, and 0.2-2.0 parts by weight of p-toluenesulfonic acid monohydrate relative to 100 parts by weight of the dodecyl glucoside; A2. React at 110-135℃ for 2-6 hours under nitrogen protection, and remove the water generated in the reaction under a pressure of 0.005-0.020MPa; A3. The esterification reaction ends when the acid value of the reaction system drops to 15-40 mg KOH / g; A4. Add 0.5-3.0 parts by weight of sodium bicarbonate relative to 100 parts by weight of dodecyl glucoside in step A1, neutralize to pH 6.0-7.5, filter, and obtain the crude esterified product of dodecyl glucoside laurate.

3. The quaternary ammonium salt compound antibacterial detergent according to claim 2, characterized in that, The crude product of dodecyl laurate glucoside esterification is processed into a layered liquid crystal intermediate through the following steps: B1. Mix 5-30 parts by weight of crude laurate dodecyl glucoside esterification product, 15-60 parts by weight of dodecyl glucoside, 10-40 parts by weight of glycerol and 10-110 parts by weight of deionized water to make the total amount of the mixture 140 parts by weight. B2. Stir at 200-800 rpm for 20-60 minutes at 50-65℃; B3. Let stand at 20-30℃ for 8-24 hours; B4. Obtain the layered liquid crystal intermediate with an interlayer spacing of 4.0-9.0 nm.

4. The quaternary ammonium salt compound antibacterial detergent according to claim 3, characterized in that, Quaternary ammonium salt intercalated layered liquid crystal intermediates are prepared by the following steps: C1. Take 140 parts by weight of the layered liquid crystal intermediate, and add 0.3-1.5 parts by weight of benzalkonium chloride and 0.2-0.8 parts by weight of disecuryl dimethyl ammonium chloride; C2. Stir at 200-800 rpm for 10-30 minutes at 20-35℃; C3. Obtain the quaternary ammonium salt intercalated layered liquid crystal intermediate with an interlayer spacing of 4.0-9.0 nm.

5. A method for preparing a quaternary ammonium salt compound antibacterial detergent as described in any one of claims 1-4, comprising the following steps: S1. Provides a pre-prepared quaternary ammonium salt intercalated layered liquid crystal intermediate; S2. Add citric acid and deionized water to the quaternary ammonium salt intercalated layered liquid crystal intermediate, wherein the amount of deionized water added is such that the total amount of the resulting product is 1000 parts by weight; mix at 20-35°C for 15-30 minutes, and filter through a 100-200 mesh filter to make the pH value of the resulting product 5.5-6.8, thereby obtaining the quaternary ammonium salt compound antibacterial detergent of claim 1.

6. The preparation method according to claim 5, characterized in that, The pH value described in step S2 was measured at 25°C.

7. The preparation method according to claim 5, characterized in that, In step S2, when the pH of the system is higher than 6.8, add 5-30 wt% citric acid aqueous solution; when the pH of the system is lower than 5.5, add sodium bicarbonate aqueous solution until the pH is 5.5-6.

8.

8. The preparation method according to claim 5, characterized in that, In step S2, the amount of citric acid added is 0.5-2.5 parts by weight, and the amount of deionized water added is 855.2-859.0 parts by weight, so that the total amount of the resulting product is 1000 parts by weight.

9. The preparation method according to claim 5, characterized in that, The filtration in step S2 is used to remove undissolved solids or gel particles.

10. The preparation method according to claim 5, characterized in that, The pH value of the quaternary ammonium salt compound antibacterial detergent obtained in step S2 is 5.8-6.5; the glycerol content is 1.5-3.0 parts by weight based on 100 parts by weight of the total amount of the obtained quaternary ammonium salt compound antibacterial detergent; and it is filled after standing at 20-30℃ for 12-24 hours.

Images