Steel surface treatment liquid with antibacterial function and preparation method thereof
By using specific combinations of ingredients in the steel surface treatment liquid, including phosphoric acid solution, Mazif salt and antibacterial agent, the problems of poor protection effect and insufficient antibacterial effect in the prior art in harsh environments are solved, and the efficient antibacterial, corrosion-resistant and self-repairing effects of the steel surface are achieved.
Patent Information
- Application Number
- CN202510365715.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-26
- Publication Date
- 2025-06-27
AI Technical Summary
The existing steel surface treatment liquid cannot provide ideal protective effect in harsh environments, and cannot increase the antibacterial effect of the steel surface, which cannot meet production needs.
A steel surface treatment solution containing phosphoric acid solution, Mazif salt, phytic acid, hydroxyethylidene diphosphonic acid, thiourea, surfactant, polydiethanol, sodium molybdate, self-healing particles containing rust converting agent, silver antibacterial agent and organosilane coupling agent is adopted. By combining these components, the antibacterial ability, corrosion resistance and adhesion of the steel surface are improved, and the self-healing function is realized.
It significantly improves the antibacterial ability and corrosion resistance of the steel surface, enhances the adhesion of the treatment liquid, and realizes automatic rust removal and repair of the steel surface through self-healing particles, meeting the protection needs in harsh environments.
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Figure CN120210797A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of steel surface treatment, and in particular to a steel surface treatment liquid with antibacterial function and its preparation method. Background Art
[0002] Pre-treating the steel surface is an essential step before steel parts manufacturing, mainly to remove oil contaminants and rust on the steel surface, and passivate the steel surface and improve its corrosion resistance. However, existing phosphating solutions mostly contain heavy metal ions such as zinc, manganese, and chromium, which increase the cost of the treatment liquid and are prone to causing environmental pollution. At the same time, although existing steel surface treatment liquids can improve the corrosion resistance of steel, in harsh environments such as high humidity and high salt spray conditions, their protective effects are not ideal, and the coating is prone to aging and cracking.
[0003] In addition, with the improvement of living standards, antibacterial products have gained consumers' favor, but the existing technology cannot increase the antibacterial effect on the steel surface during the steel surface treatment process and cannot meet the production requirements.
[0004] Therefore, the existing technology still needs to be improved and developed. Summary of the Invention
[0005] In view of the deficiencies of the above-mentioned existing technology, the purpose of the present invention is to provide a steel surface treatment liquid with antibacterial function and its preparation method, aiming to solve the problem that the existing steel surface treatment liquid cannot make the steel surface have antibacterial effect.
[0006] The technical solution of the present invention is as follows:
[0007] A steel surface treatment liquid with antibacterial function, by mass percentage, includes 33wt%-45wt% phosphoric acid solution, 35wt-48wt% Mazu salt, 1.5wt%-2.5wt% phytic acid, 4.0wt%-10.0wt% hydroxyethylidene diphosphonic acid, 0.6wt%-1.0wt% thiourea, 0.3wt%-0.6wt% surfactant, 0.1wt%-0.3wt% polydiethanol, 0.5wt%-1.0wt% sodium molybdate, 6.0wt%-10.0wt% self-healing particles containing rust converter, 3.0wt%-5.0wt% silver-based antibacterial agent, 3.0wt%-8.0wt% organosilane coupling agent, and the balance is water.
[0008] In the steel surface treatment liquid with antibacterial function, the self-healing particles containing rust converter include a rust converter and a coating layer that coats the rust converter.
[0009] The described steel surface treatment liquid with antibacterial function, wherein the rust converter includes one or more of tannic acid, phosphoric acid, and organic phosphonates; the material of the coating layer includes one or more of polyurethane, urea-formaldehyde resin, and melamine-formaldehyde resin.
[0010] The described steel surface treatment liquid with antibacterial function, wherein the silver-based antibacterial agent includes one or more of nano silver particles, silver-loaded zirconium phosphate, and silver-titanium dioxide composite materials.
[0011] The described steel surface treatment liquid with antibacterial function, wherein the organosilane coupling agent includes one or more of aminopropyltriethoxysilane, methyl tributanone oxime silane, epoxy silane, and vinyl silane.
[0012] The described steel surface treatment liquid with antibacterial function, by mass percentage, includes 35 wt% phosphoric acid solution, 36 wt% manganese phosphonate, 2 wt% phytic acid, 5 wt% hydroxyethylidene diphosphonic acid, 1.0 wt% thiourea, 0.5 wt% surfactant, 0.2 wt% polydiethanol, 0.8 wt% sodium molybdate, 8 wt% self-healing particles containing rust converter, 4 wt% silver-based antibacterial agent, 5 wt% organosilane coupling agent, and the balance is water.
[0013] The described steel surface treatment liquid with antibacterial function, by mass percentage, further includes 0.2 wt% - 1 wt% pentaerythritol, 0.5 wt% - 1 wt% acrylic acid, 0.2 wt% - 0.5 wt% tea polyphenols, and 0.1 wt% - 0.3 wt% potassium sulfite.
[0014] A preparation method of a steel surface treatment liquid with antibacterial function, including the steps:
[0015] Mix phytic acid, hydroxyethylidene diphosphonic acid, phosphoric acid solution, manganese phosphonate, thiourea, and water, and adjust to the first pH value to obtain a first mixed solution;
[0016] After performing a first heat treatment on the first mixed solution, continue to add surfactant, polydiethanol, and sodium molybdate and continue to mix. After adjusting to the second pH value, obtain a second mixed solution;
[0017] After performing a second heat treatment on the second mixed solution, adjust to the third pH value, and continue to add self-healing particles containing rust converter, silver-based antibacterial agent, and organosilane coupling agent to mix, to obtain a steel surface treatment liquid with antibacterial function.
[0018] The method for preparing a steel surface treatment liquid with antibacterial function, wherein the first pH value is 8.5-8.6; the second pH value is 4.2-4.4; and the third pH value is 6.4-6.6.
[0019] The method for preparing a steel surface treatment liquid with antibacterial function, wherein the temperature of the first heating treatment is 42°C-45°C, and the time of the first heating treatment is 100min-120min; and / or the temperature of the second heating treatment is 78°C-96°C, the time of the second heating treatment is 40min-45min, and the heating rate of the second heating treatment is 1.2°C / min-1.4°C / min.
[0020] Beneficial effect: The present invention provides a steel surface treatment liquid with antibacterial function and a preparation method thereof. The steel surface treatment liquid comprises, by mass percentage, 33wt%-45wt% of phosphoric acid solution, 35wt%-48wt% of Marif salt, 1.5wt%-2.5wt% of phytic acid, 4.0wt%-10.0wt% of hydroxyethylidene diphosphonic acid, 0.6wt%-1.0wt% of thiourea, 0.3wt%-0.6wt% of surfactant, 0.1wt%-0.3wt% of polyethylene glycol, 0.5wt%-1.0wt% of sodium molybdate, 6.0wt%-10.0wt% of self-repairing particles containing rust conversion agent, 3.0wt%-5.0wt% of silver-based antibacterial agent, 3.0wt%-8.0wt% of organic silane coupling agent, and the balance is water. In the steel surface treatment liquid provided by the present invention, a surfactant is used to infiltrate and penetrate the grease attached to the steel surface, so that it is emulsified and removed, a phosphoric acid solution is used to remove the iron oxide rust on the steel surface, and the remaining components are used as a deposition curtain layer on the steel surface, and a passivation treatment is performed at the same time to improve the corrosion resistance of the steel surface. In addition, a silver-based antibacterial agent is combined with an organic silane coupling agent to enhance the adhesion and dispersibility of silver ions on the steel surface, which not only improves the antibacterial ability of the steel surface, but also improves the corrosion resistance and adhesion of the treatment liquid; and, when rust appears on the steel surface again, the self-repairing particles containing a rust converter can automatically break and release the rust converter to react with the rust, so as to convert the loose rust into a dense protective film, thereby preventing the steel from further corrosion and achieving the purpose of automatic repair. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 The present invention is a schematic diagram of the process flow of a method for preparing a steel surface treatment liquid with antibacterial function. DETAILED DESCRIPTION
[0022] The present invention provides a steel surface treatment liquid with antibacterial function and its preparation method. To make the purpose, technical solution and effects of the present invention clearer and more definite, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.
[0023] Those skilled in the art of the present technology can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of those of ordinary skill in the art to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with their meaning in the context of the prior art, and will not be interpreted with an idealized or overly formal meaning unless specifically defined as here.
[0024] The present invention provides a steel surface treatment liquid with antibacterial function. By mass percentage, it includes 33wt%-45wt% of phosphoric acid solution, 35wt%-48wt% of Mazuév salt, 1.5wt%-2.5wt% of phytic acid, 4.0wt%-10.0wt% of hydroxyethylidene diphosphonic acid, 0.6wt%-1.0wt% of thiourea, 0.3wt%-0.6wt% of surfactant, 0.1wt%-0.3wt% of polydiethanol, 0.5wt%-1.0wt% of sodium molybdate, 6.0wt%-10.0wt% of self-repairing particles containing rust converter, 3.0wt%-5.0wt% of silver-based antibacterial agent, 3.0wt%-8.0wt% of organosilane coupling agent, and the balance is water.
[0025] In this embodiment, in the provided steel surface treatment liquid, the surfactant is used to infiltrate and penetrate the grease adhered to the steel surface to emulsify and remove it. The phosphoric acid solution is used to remove the iron oxide rust on the steel surface. The remaining components serve as a deposition curtain layer on the steel surface, and at the same time, passivation treatment is carried out to improve the corrosion resistance of the steel surface. In addition, the silver-based antibacterial agent and the organosilane coupling agent are combined to enhance the adhesion and dispersion of silver ions on the steel surface, not only improving the antibacterial ability of the steel surface, but also improving the corrosion resistance and adhesion of the treatment liquid. And, the self-repairing particles containing rust converter can automatically break and release the rust converter to react with the rust when rust appears again on the steel surface, converting the loose rust into a dense protective film, thereby preventing further corrosion of the steel and achieving the purpose of automatic repair.
[0026] Specifically, the steel surface treatment liquid with antibacterial function removes grease through the emulsifying and dispersing effects of surfactants, dissolves rust with phosphoric acid solution to clean the steel surface, providing a good foundation for subsequent treatment. Moreover, through phosphating and passivating treatment with manganese dihydrogen phosphate (Marinov salt), a thin and dense phosphating film is formed on the steel surface to improve corrosion resistance and enhance the adhesion between the coating and the steel substrate, providing a good bottom layer for subsequent painting and other processes. Meanwhile, other components form a protective layer on the steel surface. Among them, the organosilane coupling agent can enhance the adhesion and dispersibility of the silver-based antibacterial agent on the steel surface, making the organosilane coupling agent not only improve the antibacterial effect but also enhance the corrosion resistance and adhesion of the treatment liquid. In addition, the self-repairing particles containing rust converter can provide a self-repairing function for the subsequent rusting of steel. When microcracks occur in the protective layer on the steel surface due to external force or corrosion, the stress concentration at the crack tip will cause the self-repairing particles containing rust converter to break, releasing the rust converter. As a result, the rust converter reacts chemically with the rust to convert it into a stable compound, thus achieving the purpose of rust removal and rust prevention.
[0027] In some embodiments, the self-repairing particles containing rust converter include a rust converter and a coating layer that coats the rust converter. The coating structure can store the rust converter in the protective layer on the steel surface. When the steel surface rusts or the protective layer breaks, the stress generated by rusting or the breakage of the protective layer can cause the coating layer to break, thereby releasing the rust converter, and then rust removal and repair of the steel surface can be carried out.
[0028] In some embodiments, the rust converter includes one or more of tannic acid, phosphoric acid, and organic phosphonates; the material of the coating layer includes one or more of polyurethane, urea-formaldehyde resin, and melamine-formaldehyde resin. The tannic acid and the phosphoric acid can react chemically with rust (the main component is iron oxide) to form stable ferric tannate and ferric phosphate, which play a blocking role on the steel surface to prevent further formation of rust, thereby preventing more corrosion; while the organic phosphonate can chelate with iron ions in the rust to form a chelate, accelerating the conversion of rust and improving the rust conversion rate, thus realizing the self-repair of rust on the steel surface. The coating layer of the above materials has good mechanical properties, good film-forming properties, and the shell thickness can be controlled, which can provide a good coating effect for the rust converter.
[0029] In some embodiments, the preparation method of the self-repairing particles containing rust converter includes the steps:
[0030] S1: Mix the rust converter with water to obtain a rust converter solution;
[0031] S2: Stir the polymer prepolymer and the rust converter solution to obtain a mixed solution;
[0032] S3: Pour the mixed solution into a mold, and after curing, obtain self-healing particles containing a rust converter.
[0033] In some embodiments, the concentration of the rust converter solution is 1 wt% - 5 wt%.
[0034] In some embodiments, the rotation speed of the stirring treatment is between 1000 - 2000 rpm, and the time is 1 - 2 hours. Under this condition, a coating state can be formed.
[0035] In some embodiments, the silver-based antibacterial agent includes one or more of nano silver particles, silver-loaded zirconium phosphate, and silver-titanium dioxide composites. The above silver-based antibacterial agent can effectively improve the antibacterial performance of steel in the steel surface treatment solution and extend its service life.
[0036] In some embodiments, the organosilane coupling agent includes one or more of aminopropyltriethoxysilane, methyltris(methylethylketoxime)silane, epoxy silane, and vinyl silane. Aminopropyltriethoxysilane contains an amino functional group and can undergo a chemical reaction with the silver-based antibacterial agent to form a stable antibacterial coating. Aminopropyltriethoxysilane can enhance the adhesion and dispersion of silver ions on the high-speed rail surface, thereby improving the antibacterial effect; methyltris(methylethylketoxime)silane can react with the active functional groups of the steel substrate to form chemical covalent bonds, enhancing the binding force between the silver-based antibacterial agent and the steel surface; epoxy silane can form a stable network structure with the silver-based antibacterial agent, improving the stability and durability of the antibacterial coating; vinyl silane has good reactivity and can synergistically act with the silver-based antibacterial agent to improve the antibacterial performance. The above organosilane coupling agents can all improve the antibacterial effect and at the same time enhance the adhesion and durability of the antibacterial coating.
[0037] In some embodiments, the steel surface treatment solution with antibacterial function, by mass percentage, includes 35 wt% phosphoric acid solution, 36 wt% Mazu salt, 2 wt% phytic acid, 5 wt% hydroxyethylidene diphosphonic acid, 1.0 wt% thiourea, 0.5 wt% surfactant, 0.2 wt% polydiethanol, 0.8 wt% sodium molybdate, 8 wt% self-healing particles containing a rust converter, 4 wt% silver-based antibacterial agent, 5 wt% organosilane coupling agent, and the balance is water. The steel surface treatment solution prepared according to this mass percentage has good degreasing, rust removal, phosphating, and passivation functions, and also has good antibacterial function, and can automatically remove rust and repair when rust appears again on the subsequent steel surface.
[0038] In some embodiments, the steel surface treatment liquid with antibacterial function, by mass percentage, further comprises 0.2wt%-1wt% of pentaerythritol, 0.5wt%-1wt% of acrylic acid, 0.2wt%-0.5wt% of tea polyphenols, and 0.1wt%-0.3wt% of potassium sulfite. The film-forming properties of pentaerythritol and pentaerythritol, combined with the antioxidant properties of tea polyphenols and potassium sulfite, can significantly improve the corrosion resistance of the steel surface; and the combination of acrylic acid and pentaerythritol can enhance the adhesion of the treatment liquid to the steel surface, making the protective film more firm.
[0039] In some embodiments, the surfactant includes one or more of sodium alkyl sulfonate, sodium dodecyl benzene sulfonate, sodium dodecyl sulfate, polyoxyethylene fatty alcohol ether, and polyoxyethylene-polyoxypropylene polymer.
[0040] In addition, as Figure 1 shown, the present invention also provides a preparation method of a steel surface treatment liquid with antibacterial function, comprising the steps:
[0041] Step S10: Mix phytic acid, hydroxyethylidene diphosphonic acid, phosphoric acid solution, Mazu salt, thiourea, and water, and adjust to the first pH value to obtain a first mixed solution;
[0042] Step S20: After performing the first heat treatment on the first mixed solution, continue to add the surfactant, polyethylene glycol, and sodium molybdate and continue to mix. After adjusting to the second pH value, obtain a second mixed solution;
[0043] Step S30: After performing the second heat treatment on the second mixed solution, adjust to the third pH value, and continue to add self-repairing particles containing a rust converter, a silver-based antibacterial agent, and an organosilane coupling agent for mixing to obtain a steel surface treatment liquid with antibacterial function.
[0044] In this embodiment, the preparation method has a simple process, and a steel surface treatment liquid with antibacterial function can be prepared by performing mixing and heating step by step; moreover, the prepared steel surface treatment liquid has functions of degreasing, rust removal, phosphating, passivation, antibacterial, and self-repairing, improving the corrosion resistance of the steel surface.
[0045] In some embodiments, the first pH value is 8.5 - 8.6; the second pH value is 4.2 - 4.4; the third pH value is 6.4 - 6.6. By regulating the pH multiple times, the most suitable acid-base environment can be provided for the reaction, promoting the progress of the reaction, and improving the reaction efficiency and conversion rate.
[0046] In some embodiments, the temperature of the first heat treatment is 42°C - 45°C, and the time of the first heat treatment is 100 min - 120 min; and / or, the temperature of the second heat treatment is 78°C - 96°C, the time of the second heat treatment is 40 min - 45 min, and the heating rate of the second heat treatment is 1.2°C / min - 1.4°C / min. By using the first heat treatment and the second heat treatment, the progress of the reaction is improved, and the preparation efficiency of the steel treatment liquid is improved.
[0047] The following further gives examples to illustrate the present invention in detail. It should also be understood that the following examples are only used to further illustrate the present invention and cannot be construed as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention all fall within the protection scope of the present invention.
[0048] Example 1
[0049] This example provides a steel surface treatment liquid with antibacterial function. By mass percentage, it includes 33 wt% phosphoric acid solution, 35 wt% Mazu salt, 1.5 wt% phytic acid, 4.0 wt% hydroxyethylidene diphosphonic acid, 0.6 wt% thiourea, 0.3 wt% alkyl sulfonate, 0.1 wt% polydiethanol, 0.5 wt% sodium molybdate, 6.0 wt% self-repairing particles containing rust converter, 3.0 wt% nano silver particles, 3.0 wt% aminopropyltriethoxysilane, and the balance is water. Among them, the self-repairing particles containing rust converter are tannic acid coated with polyurethane.
[0050] The preparation steps are as follows: Mix phytic acid, hydroxyethylidene diphosphonic acid, phosphoric acid solution, Mazu salt, thiourea and water, and adjust the pH value to 8.5 to obtain a first mixed solution; Heat the first mixed solution to 43°C, continue to add alkyl sulfonate, polydiethanol, sodium molybdate and continue to mix, and after adjusting the pH value to 4.2, obtain a second mixed solution; Heat the second mixed solution to 82°C, adjust the pH value to 6.5, and continue to add self-repairing particles containing rust converter, nano silver particles, aminopropyltriethoxysilane for mixing to obtain a steel surface treatment liquid with antibacterial function.
[0051] Example 2
[0052] This embodiment provides a steel surface treatment liquid with antibacterial function. By mass percentage, it includes 35 wt% of phosphoric acid solution, 36 wt% of Mazu salt, 2 wt% of phytic acid, 5 wt% of hydroxyethylidene diphosphonic acid, 1 wt% of thiourea, 0.5 wt% of alkyl sulfonate, 0.2 wt% of polydiethanol, 0.8 wt% of sodium molybdate, 8.0 wt% of self-repairing particles containing rust converter, 4.0 wt% of nano silver particles, 5.0 wt% of aminopropyltriethoxysilane, and the balance is water. Among them, the self-repairing particles containing rust converter are tannic acid coated with polyurethane.
[0053] The preparation steps are as follows: Mix phytic acid, hydroxyethylidene diphosphonic acid, phosphoric acid solution, Mazu salt, thiourea and water, and adjust the pH value to 8.5 to obtain the first mixed solution; Heat the first mixed solution to 43 °C, continue to add alkyl sulfonate, polydiethanol, sodium molybdate and continue to mix. After adjusting the pH value to 4.2, obtain the second mixed solution; Heat the second mixed solution to 82 °C, adjust the pH value to 6.5, and continue to add self-repairing particles containing rust converter, nano silver particles, aminopropyltriethoxysilane for mixing to obtain a steel surface treatment liquid with antibacterial function.
[0054] Example 3
[0055] This embodiment provides a steel surface treatment liquid with antibacterial function. By mass percentage, it includes 33 wt% of phosphoric acid solution, 35 wt% of Mazu salt, 1.5 wt% of phytic acid, 4.0 wt% of hydroxyethylidene diphosphonic acid, 0.6 wt% of thiourea, 0.3 wt% of alkyl sulfonate, 0.1 wt% of polydiethanol, 0.5 wt% of sodium molybdate, 6.0 wt% of self-repairing particles containing rust converter, 3.0 wt% of nano silver particles, 3.0 wt% of aminopropyltriethoxysilane, 0.5 wt% of pentaerythritol, 0.8 wt% of acrylic acid, 0.2 wt% of tea polyphenols, 0.2 wt% of potassium sulfite, and the balance is water. Among them, the self-repairing particles containing rust converter are tannic acid coated with polyurethane.
[0056] The preparation steps are as follows: Mix phytic acid, hydroxyethylidene diphosphonic acid, phosphoric acid solution, Mazu salt, thiourea and water, and adjust the pH value to 8.5 to obtain the first mixed solution; Heat the first mixed solution to 43 °C, continue to add alkyl sulfonate, polydiethanol, sodium molybdate, pentaerythritol, acrylic acid, tea polyphenols, potassium sulfite and continue to mix. After adjusting the pH value to 4.2, obtain the second mixed solution; Heat the second mixed solution to 82 °C, adjust the pH value to 6.5, and continue to add self-repairing particles containing rust converter, nano silver particles, aminopropyltriethoxysilane for mixing to obtain a steel surface treatment liquid with antibacterial function.
[0057] Comparative Example 1
[0058] This embodiment provides a steel surface treatment solution, which, by mass percentage, includes 33 wt% of phosphoric acid solution, 35 wt% of Mazu salt, 1.5 wt% of phytic acid, 4.0 wt% of hydroxyethylidene diphosphonic acid, 0.6 wt% of thiourea, 0.3 wt% of alkyl sulfonate, 0.1 wt% of polydiethanol, 0.5 wt% of sodium molybdate, and the balance is water. Among them, the self-healing particles containing a rust converter are tannic acid coated with polyurethane.
[0059] The preparation steps are as follows: Mix phytic acid, hydroxyethylidene diphosphonic acid, phosphoric acid solution, Mazu salt, thiourea and water, and adjust the pH value to 8.5 to obtain a first mixed solution; Heat the first mixed solution to 43 °C, continue to add alkyl sulfonate, polydiethanol, sodium molybdate and continue to mix, and after adjusting the pH value to 4.2, obtain a second mixed solution; Heat the second mixed solution to 82 °C and adjust the pH value to 6.5 to obtain a steel surface treatment solution with antibacterial function.
[0060] Comparative Example 2
[0061] This embodiment provides a steel surface treatment solution, which, by mass percentage, includes 33 wt% of phosphoric acid solution, 35 wt% of Mazu salt, 1.5 wt% of phytic acid, 4.0 wt% of hydroxyethylidene diphosphonic acid, 0.6 wt% of thiourea, 0.3 wt% of alkyl sulfonate, 0.1 wt% of polydiethanol, 0.5 wt% of sodium molybdate, 0.5 wt% of pentaerythritol, 0.8 wt% of acrylic acid, 0.2 wt% of tea polyphenols, 0.2 wt% of potassium sulfite, and the balance is water. Among them, the self-healing particles containing a rust converter are tannic acid coated with polyurethane.
[0062] The preparation steps are as follows: Mix phytic acid, hydroxyethylidene diphosphonic acid, phosphoric acid solution, Mazu salt, thiourea and water, and adjust the pH value to 8.5 to obtain a first mixed solution; Heat the first mixed solution to 43 °C, continue to add alkyl sulfonate, polydiethanol, sodium molybdate, pentaerythritol, acrylic acid, tea polyphenols, potassium sulfite and continue to mix, and after adjusting the pH value to 4.2, obtain a second mixed solution; Heat the second mixed solution to 82 °C and adjust the pH value to 6.5 to obtain a steel surface treatment solution with antibacterial function.
[0063] Functional tests were carried out on the steel surface treatment solutions prepared in Examples 1-3 and Comparative Examples 1-2 to systematically evaluate their effects, as follows:
[0064] 1) Salt spray test
[0065] Test standard: ASTM B117.
[0066] Experimental instrument: WZQ-03 neutral salt spray test machine.
[0067] Product Name: 10-inch Ground Anchor - OR (treated with the steel surface treatment solutions prepared in Examples 1 to 3 and Comparative Examples 1 to 2 of the present invention respectively).
[0068] Test Parameters: (1) Test Conditions: 95% pure water + 5% sodium chloride, formulated into a saline solution with a mass fraction of 5.0%, pH value of 4.79;
[0069] (2) Process Parameters: Spray pressure is 0.10 Mpa, saturation barrel temperature is 47.0 °C, salt spray box temperature is 35.0 °C, collection flow volume is 1.4, collection liquid salinity is 3.9, and pH value of the collection liquid is 6.87.
[0070] Test Results: After 24-hour and 36-hour NSS tests, the surface conditions of the samples in different groups are shown in Table 1 below.
[0071]
[0072] 2) Cross-Cut Test
[0073] Test Standard: ASTM D3359.
[0074] Product Name: 16-inch Ground Anchor - OR (treated with the steel surface treatment solutions prepared in Examples 1 to 3 and Comparative Examples 1 to 2 of the present invention respectively).
[0075] Test Results: The surface coating conditions of the samples in different groups are shown in Table 2 below.
[0076]
[0077] 3) Antibacterial Effect Test
[0078] Test Standard: GB / T 21866—2008
[0079] Specimen Preparation: Cut the steel specimen to be tested into a certain size, such as 10 mm × 10 mm × 3 mm, wash and degrease it, fix one end of a copper wire on the specimen surface, then cold inlay it with epoxy resin, and expose the other end of the wire. After the epoxy resin dries, polish the specimen to expose the other end surface. Treat the steel surface with the steel surface treatment solutions prepared in Examples 1 - 3 and Comparative Examples 1 - 2 respectively, ultrasonically clean it with acetone solution, and sterilize it under an ultraviolet lamp for 20 - 40 minutes for standby.
[0080] Bacterial Suspension Preparation: After culturing bacteria in a test tube with a fresh slant to the logarithmic growth phase, add a certain amount of physiological saline solution, scrape the bacteria on the slant with an inoculation loop, and serially dilute the bacterial suspension into a bacterial solution with a certain concentration by turbidimetry, such as 4 - 6×10 6cfu / ml.
[0081] Action of the sample on bacteria: Place the prepared sample in a beaker containing a bacterial solution of the corresponding concentration and immerse it. The other end of the copper wire is exposed outside the beaker. Seal the beaker and place it in a water bath at 35 - 37°C for 2 - 14 days.
[0082] Determination of viable bacteria count: After the specified time, elute the sample, determine the viable bacteria count in the eluate, compare it with the untreated control sample, and calculate the antibacterial rate.
[0083] Test results: The surface antibacterial rates of samples in different groups are shown in Table 3 below.
[0084]
[0085] In summary, the present invention provides a steel surface treatment liquid with antibacterial function and its preparation method. By mass percentage, the steel surface treatment liquid includes 33wt% - 45wt% phosphoric acid solution, 35wt - 48wt% manganese phosphate, 1.5wt% - 2.5wt% phytic acid, 4.0wt% - 10.0wt% hydroxyethylidene diphosphonic acid, 0.6wt% - 1.0wt% thiourea, 0.3wt% - 0.6wt% surfactant, 0.1wt% - 0.3wt% polyethylene glycol, 0.5wt% - 1.0wt% sodium molybdate, 6.0wt% - 10.0wt% self - repairing particles containing rust converter, 3.0wt% - 5.0wt% silver - based antibacterial agent, 3.0wt% - 8.0wt% organosilane coupling agent, and the balance is water. In the steel surface treatment liquid provided by the present invention, the surfactant infiltrates and wets the grease on the steel surface, emulsifies and removes it. The phosphoric acid solution removes the iron oxide rust on the steel surface. The remaining components form a deposition coating on the steel surface and simultaneously carry out passivation treatment to improve the corrosion resistance of the steel surface. In addition, the combination of the silver - based antibacterial agent and the organosilane coupling agent enhances the adhesion and dispersion of silver ions on the steel surface, not only improving the antibacterial ability of the steel surface but also improving the corrosion resistance and adhesion of the treatment liquid. Moreover, when rust reappears on the steel surface, the self - repairing particles containing rust converter automatically break and release the rust converter to react with the rust, converting the loose rust into a dense protective film, thereby preventing further corrosion of the steel and achieving the purpose of automatic repair.
[0086] It should be understood that the application of the present invention is not limited to the above examples. For those of ordinary skill in the art, improvements or transformations can be made according to the above description. All such improvements and transformations should fall within the protection scope of the appended claims of the present invention.
Claims
1. A steel surface treatment liquid with antibacterial function, characterized in that: Calculated by mass percentage, the invention comprises 33wt%-45wt% of phosphoric acid solution, 35wt%-48wt% of Marib salt, 1.5wt%-2.5wt% of phytic acid, 4.0wt%-10.0wt% of hydroxyethylidene diphosphonic acid, 0.6wt%-1.0wt% of thiourea, 0.3wt%-0.6wt% of surfactant, 0.1wt%-0.3wt% of polyethylene glycol, 0.5wt%-1.0wt% of sodium molybdate, 6.0wt%-10.0wt% of self-repairing particles containing rust conversion agent, 3.0wt%-5.0wt% of silver antibacterial agent, 3.0wt%-8.0wt% of organic silane coupling agent, and the balance is water.
2. The steel surface treatment liquid with antibacterial function according to claim 1, characterized in that: The self-repairing particles containing a rust converter include a rust converter and a coating layer for coating the rust converter.
3. The steel surface treatment liquid with antibacterial function according to claim 2, characterized in that: The rust conversion agent includes one or more of tannic acid, phosphoric acid, and organic phosphonates; the material of the coating layer includes one or more of polyurethane, urea-formaldehyde resin, and melamine-formaldehyde resin.
4. The steel surface treatment liquid with antibacterial function according to claim 1, characterized in that: The silver-based antibacterial agent includes one or more of nano silver particles, silver-loaded zirconium phosphate, and silver-titanium dioxide composite materials.
5. The steel surface treatment liquid with antibacterial function according to claim 1, characterized in that: The organic silane coupling agent includes one or more of aminopropyltriethoxysilane, methyltributylidene oxime silane, epoxy silane and vinyl silane.
6. The steel surface treatment liquid with antibacterial function according to claim 1, characterized in that: The steel surface treatment liquid with antibacterial function comprises, by mass percentage, 35wt% of phosphoric acid solution, 36wt% of Marif salt, 2wt% of phytic acid, 5wt% of hydroxyethylidene diphosphonic acid, 1.0wt% of thiourea, 0.5wt% of surfactant, 0.2wt% of polyethylene glycol, 0.8wt% of sodium molybdate, 8wt% of self-repairing particles containing rust conversion agent, 4wt% of silver antibacterial agent, 5wt% of organic silane coupling agent, and the balance is water.
7. The steel surface treatment liquid with antibacterial function according to claim 1, characterized in that: The steel surface treatment liquid with antibacterial function further comprises, by mass percentage, 0.2wt%-1wt% of pentaerythritol, 0.5wt%-1wt% of acrylic acid, 0.2wt%-0.5wt% of tea polyphenols and 0.1wt%-0.3wt% of potassium sulfite.
8. A method for preparing a steel surface treatment liquid having antibacterial function according to any one of claims 1 to 7, characterized in that: Includes steps: Mixing phytic acid, hydroxyethylidene diphosphonic acid, phosphoric acid solution, Marib salt, thiourea and water, and adjusting the pH value to a first pH value to obtain a first mixed solution; After the first mixed solution is subjected to a first heating treatment, a surfactant, polyethylene glycol, and sodium molybdate are continuously added and mixed, and after the pH value is adjusted to a second pH value, a second mixed solution is obtained; After the second mixed solution is subjected to a second heating treatment, it is adjusted to a third pH value, and self-repairing particles containing a rust conversion agent, a silver-based antibacterial agent, and an organic silane coupling agent are continuously added and mixed to obtain a steel surface treatment liquid with antibacterial function.
9. The method for preparing a steel surface treatment liquid having antibacterial function according to claim 8, characterized in that: The first pH value is 8.5-8.6; the second pH value is 4.2-4.4; and the third pH value is 6.4-6.
6.
10. The method for preparing a steel surface treatment liquid having antibacterial function according to claim 8, characterized in that: The temperature of the first heating treatment is 42°C-45°C, and the time of the first heating treatment is 100min-120min; and / or the temperature of the second heating treatment is 78°C-96°C, and the time of the second heating treatment is 40min-45min, and the heating rate of the second heating treatment is 1.2°C / min-1.4°C / min.