Neutral metal cleaning agent and preparation method thereof

Abstract

The invention relates to the field of metal cleaning agents, in particular to a neutral metal cleaning agent and a preparation method thereof. The metal cleaning agent is prepared from the following raw materials in percentage by mass: 3%-8% of modified urchin-shaped particles, 2%-5% of 2-amino-4, 6-dihydroxy-5-methylpyrimidine, 1%-3% of a surfactant, 0.1%-1.0% of a defoaming agent, 1%-2% of a chelating agent and the balance of water, wherein the modified sea urchin-shaped particles are obtained by modifying sea urchin-shaped particles with betaine monohydrate. The modified sea urchin-shaped particles provide physical grinding, antibacterial and degerming effects, and 2-amino-4, 6-dihydroxy-5-methylpyrimidine can be adsorbed on the metal surface to form an anti-rust protective film and has a synergistic effect with other components, so that the decontamination capability and stability of the water-based metal cleaning agent are improved, and the cleaning work becomes more efficient.

Description

Technical Field

[0001] The invention relates to the field of metal cleaning agents, and in particular to a neutral metal cleaning agent and a preparation method thereof. Background Art

[0002] In many industrial fields, such as machinery manufacturing, automobile industry, aerospace, etc., cleaning of metal parts is an essential link. These metal parts will be contaminated with various pollutants such as oil, dirt, rust and coolant residue during processing. For example, in automobile engine manufacturing, after metal parts undergo cutting, grinding and other processing procedures, a large amount of cutting oil and metal debris will adhere to the surface. If they are not effectively cleaned, it will affect the assembly accuracy and performance of the engine.

[0003] Traditional metal cleaning agents include acidic, alkaline, and neutral. Acidic metal cleaning agents can effectively remove rust and oxides, but they are highly corrosive. Improper use will shorten the life of the metal and pose safety risks. Alkaline cleaning agents such as sodium hydroxide solution can remove oil stains, but high alkalinity may corrode certain metals, limiting their application in the cleaning of precision or multiple metal parts. In addition, strong acid and alkali cleaning agents also pose certain threats to the safety of operators during use, such as skin burns.

[0004] Neutral metal cleaners can effectively clean dirt without damaging the metal substrate. Whether it is common metals such as steel, copper, aluminum, or some alloy materials, neutral cleaners can provide a relatively mild cleaning environment, avoiding the corrosion problems that may be caused by acidic and alkaline cleaners. Because its pH value is close to neutral, it has good applicability in various industrial environments and in the cleaning of different metal materials. For example, in the electronics industry, it can clean metal casings without corroding the internal electronic components; in the aerospace field, it can clean metal parts while meeting the requirements of high precision and high reliability. However, existing neutral metal cleaners have problems such as insufficient cleaning ability and complex operation. Summary of the invention

[0005] In order to solve the deficiencies in the prior art, the present invention provides a neutral metal cleaning agent and a preparation method thereof, which can not only clean most of the dirt, such as salt, oil smoke, organic and inorganic compounds, but also slow down metal corrosion, friction and wear, and has a certain anti-rust performance. The most critical feature is that the product itself is neutral, which facilitates the subsequent surface treatment of the product and does not pollute the environment.

[0006] The neutral metal cleaning agent is composed of the following raw materials in percentage by mass: 3%-8% of sea urchin-shaped particles, 2%-5% of 2-amino-4,6-dihydroxy-5-methylpyrimidine, 1%-3% of surfactant, 0.1%-1.0% of defoaming agent, 1%-2% of chelating agent, and the balance is water.

[0007] Furthermore, the modified sea urchin-shaped particles are sea urchin-shaped particles modified by betaine monohydrate.

[0008] Furthermore, the method for preparing the modified sea urchin-shaped particles comprises the following steps:

[0009] The sea urchin-like particles and deionized water are mixed in a mass ratio of 1:(100-800), and ultrasonically dispersed for 15-30 minutes to obtain a suspension; mixed with a stearic acid-soluble ethanol solution in a mass ratio of (2-3):1, stirred at 60-70°C for 30-70 minutes, filtered, washed, and dried to obtain modified sea urchin-like particles; the concentration of stearic acid in the stearic acid-soluble ethanol solution is 8-15wt%.

[0010] In certain embodiments, the urchin-shaped particles are urchin-shaped zinc oxide;

[0011] The preparation method of the sea urchin-shaped zinc oxide is as follows: zinc nitrate and NaOH are mixed in a mass ratio of 3:3-5, and distilled water is added until the pH value of the mixed solution is 10-11; the mixed solution is treated in ultrasound with a power of 100-200W for 15-25min; then, the mixed solution is stirred under reflux for 10-14 hours, filtered, washed, and dried to obtain sea urchin-shaped particles.

[0012] In certain embodiments, the surfactant is sodium cocoyl glycinate.

[0013] In certain embodiments, the defoaming agent is polyoxyethylene polyoxypropanolamine ether.

[0014] In certain embodiments, the chelating agent is disodium EDTA.

[0015] The preparation method of the neutral metal cleaning agent comprises the following steps:

[0016] The modified sea urchin-shaped particles, 2-amino-4,6-dihydroxy-5-methylpyrimidine, a surfactant, a defoaming agent, a chelating agent and water are added respectively and fully mixed to obtain a finished metal cleaning agent.

[0017] The beneficial effects of the present invention are:

[0018] The cleaning agent involved in the present invention is a neutral, water-based metal cleaning agent, and its formula contains modified sea urchin-shaped particles, 2-amino-4,6-dihydroxy-5-methylpyrimidine and surfactants, etc. These ingredients are carefully proportioned and compounded to work together to achieve an ideal cleaning effect.

[0019] First, the modified sea urchin-like particles are prepared by modifying sea urchin-like particles with betaine monohydrate; they provide a physical grinding effect in the cleaning agent of the present invention, and can generate a strong mechanical friction force during the cleaning process, effectively breaking the adhesion between the pollutants and the metal surface, thereby accelerating the dirt removal process. In addition, betaine monohydrate modification introduces quaternary amine groups on the surface of the sea urchin-like particles, which can avoid bacteria from destroying the cleaning agent, weaken the effect of bacteria that multiply in the oil on the metal surface on the removal of oil, and enhance the dispersibility of the sea urchin-like particles in water, further improving the decontamination ability and stability of the water-based metal cleaning agent, making the cleaning work more efficient.

[0020] Secondly, the cleaning agent of the present invention adds 2-amino-4,6-dihydroxy-5-methylpyrimidine, which can be adsorbed on the metal surface, and through the hydrogen bonding of its amino, ketone and other active groups, it combines to form a protective film, significantly improving the rust resistance of the metal surface. And by optimizing the ratio of sea urchin-shaped particles to 2-amino-4,6-dihydroxy-5-methylpyrimidine, and coordinating with other ingredients, the cleaning agent can achieve a better cleaning effect while maintaining neutrality, while reducing damage to the metal surface. Therefore, the cleaning agent of the present invention is not only suitable for cleaning various metal surfaces, but also can effectively extend the service life of metal products, and has a wide range of application prospects. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the embodiments.

[0022] The following sea urchin-shaped particles are sea urchin-shaped zinc oxide, which is prepared by the following method: zinc nitrate and NaOH are mixed in a mass ratio of 3:4, and distilled water is added until the pH value of the mixed solution is 10-11; the mixed solution is treated in ultrasound with a power of 200W for 20 minutes; then stirred under reflux for 12 hours, filtered, washed, and dried to obtain sea urchin-shaped particles.

[0023] The modified sea urchin-like particles are prepared by the following method: sea urchin-like particles and deionized water are mixed in a mass ratio of 1:200, and ultrasonically dispersed for 20 minutes to obtain a suspension; mixed with a stearic acid-soluble ethanol solution in a mass ratio of 2:1, stirred at 60-70°C for 40 minutes, filtered, washed, and dried to obtain modified sea urchin-like particles; the concentration of stearic acid in the stearic acid-soluble ethanol solution is 10wt%.

[0024] Examples 1-8

[0025] The modified sea urchin-shaped particles, 2-amino-4,6-dihydroxy-5-methylpyrimidine, sodium cocoyl glycinate, polyoxyethylene polyoxypropanolamine ether, disodium ethylenediaminetetraacetate, and water are added respectively and fully mixed to obtain a neutral metal cleaning agent. The mass percentage of each raw material (the balance is water) is shown in Table 1.

[0026] Table 1

[0027]

[0028] Comparative Example 1

[0029] The difference between Comparative Example 1 and Example 1 is that “modified sea urchin-shaped particles” are changed to “sea urchin-shaped particles”, and the rest is the same as Example 1.

[0030] Comparative Example 2

[0031] The difference between Comparative Example 2 and Example 1 is that the "modified sea urchin-shaped particles" are changed to "modified spherical particles", and the preparation method of the modified spherical particles is as follows: spherical zinc oxide (purchased from Qiyue Biological, with a particle size of 30-50 nm) and deionized water are mixed in a mass ratio of 1:200, and ultrasonically dispersed for 20 minutes to obtain a suspension; mixed with a stearic acid-soluble ethanol solution in a mass ratio of 2:1, stirred at 60-70°C for 40 minutes, filtered, washed, and dried to obtain modified spherical particles; the concentration of stearic acid in the stearic acid-soluble ethanol solution is 10wt%; the rest is the same as Example 1.

[0032] Comparative Example 3

[0033] The difference between Comparative Example 2 and Example 1 is that the added amount of "modified sea urchin-shaped particles" is changed to 0 g, and the rest is the same as Example 1.

[0034] Effect example

[0035] The properties of the cleaning agents obtained in the examples and comparative examples were tested, including appearance (visual inspection), cleaning power, corrosion performance, and defoaming performance. The test results are shown in Table 2.

[0036] The cleaning power is tested according to the mass method in JB / T4323, that is, the 45# steel after being dipped in oil (the oil includes the following raw materials in mass fraction: 2 parts of N321JL hydraulic oil, 1 part of industrial white vaseline, and 1 part of petroleum barium sulfonate) is weighed, and washed with a washing machine for 3 to 5 minutes with a cleaning agent. After drying, it is weighed and calculated, and the oil washing rate (%) is calculated based on the weight loss before and after washing.

[0037] The corrosion performance was tested according to JB / T4323. The surface of the 45# steel test piece was first polished with sandpaper, then soaked and cleaned with acetone, weighed after drying, and then soaked in the cleaning agent and placed at room temperature for 6 hours. It was then cleaned with deionized water and anhydrous ethanol, weighed after drying, and the mass changes before and after soaking were recorded.

[0038] The defoaming performance is tested according to JB / T4323. The cleaning agent is put into a measuring cylinder, shaken up and down for 1 minute, then left to stand at room temperature for 10 minutes, and the residual foam height is measured.

[0039] Table 2

[0040] Appearance Oil washing rate (%) Mass change (mg) Foam height (mm) Example 1 Uniform, no precipitation 98.77 ＜2 2.5 Example 2 Uniform, no precipitation 93.49 ＜2 5 Example 3 Uniform, no precipitation 97.45 ＜2 4.5 Example 4 Uniform, no precipitation 96.53 ＜2 2 Example 5 Uniform, no precipitation 99.12 ＜2 2.5 Example 6 Uniform, no precipitation 98.65 ＜2 5 Example 7 Uniform, no precipitation 98.25 ＜2 2.5 Example 8 Uniform, no precipitation 98.33 ＜2 3 Comparative Example 1 precipitation 81.47 ＜2 3 Comparative Example 2 Uniform, no precipitation 85.84 ＜2 4 Comparative Example 3 Uniform, no precipitation 69.54 ＜2 4.5

[0041] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A neutral metal cleaning agent, characterized in that: The invention is composed of the following raw materials in percentage by mass: 3%-8% of modified sea urchin-shaped particles, 2%-5% of 2-amino-4,6-dihydroxy-5-methylpyrimidine, 1%-3% of surfactant, 0.1%-1.0% of defoaming agent, 1%-2% of chelating agent, and the balance of water.

2. The neutral metal cleaning agent according to claim 1, characterized in that: The modified sea urchin-shaped particles are prepared by modifying sea urchin-shaped particles with betaine monohydrate.

3. The neutral metal cleaning agent according to claim 1, characterized in that: The sea urchin-shaped particles are sea urchin-shaped zinc oxide.

4. The neutral metal cleaning agent according to claim 1, characterized in that: The surfactant is sodium cocoyl glycinate.

5. The neutral metal cleaning agent according to claim 1, characterized in that: The defoamer is polyoxyethylene polyoxypropanolamine ether.

6. The neutral metal cleaning agent according to claim 1, characterized in that: The chelating agent is disodium ethylenediaminetetraacetate.

7. A method for preparing the metal cleaning agent according to claim 1, characterized in that: The preparation method of the neutral metal cleaning agent comprises the following steps: adding modified sea urchin-shaped particles, 2-amino-4,6-dihydroxy-5-methylpyrimidine, a surfactant, a defoaming agent, a chelating agent and water respectively and mixing them fully to obtain a finished metal cleaning agent.

8. The method for preparing the metal cleaning agent according to claim 7, characterized in that: The method for preparing the modified sea urchin-shaped particles comprises the following steps: The sea urchin-like particles and deionized water are mixed in a mass ratio of 1:(100-800), and ultrasonically dispersed for 15-30 minutes to obtain a suspension; mixed with a stearic acid-soluble ethanol solution in a mass ratio of (2-3):1, stirred at 60-70°C for 30-70 minutes, filtered, washed, and dried to obtain modified sea urchin-like particles; the concentration of stearic acid in the stearic acid-soluble ethanol solution is 8-15wt%.

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