Water-based cleaning agent as well as preparation method and use method thereof

Abstract

The invention belongs to the field of cleaning agents, and particularly relates to a water-based cleaning agent as well as a preparation method and a use method thereof. The invention discloses a water-based cleaning agent which comprises the following components: 5-10 wt% of a surfactant, 3-5 wt% of N-methyl pyrrolidone, 10-13 wt% of an ether substance, 0.1-0.5 wt% of a corrosion inhibitor, 0.3-1 wt% of a complexing agent, 2-6 wt% of a pH regulator and the balance of water, totaling 100%. The surfactant is selected from at least two of fatty alcohol-polyoxyethylene ether, a polyether gemini surfactant, Dynol 604, Surfynol 465, lauryl sodium sulfate, Surfynol 420 and Surfynol 440, and the surfactant is selected from at least two of the fatty alcohol-polyoxyethylene ether, the polyether gemini surfactant, the Dynol 604, the Surfynol 465, the lauryl sodium sulfate, the Surfynol 420 and the Surfynol 440. The water-based cleaning agent is good in low-foam performance, and pollutants can be effectively removed through a surfactant compound system; corrosion of a metal contact or swelling of a high polymer material cannot be caused; and the paint is non-flammable and non-explosive, safe to use and environment-friendly.

Description

Technical Field

[0001] This application belongs to the field of cleaning agents, specifically relating to a water-based cleaning agent and its preparation and application methods. Background Technology

[0002] With the rapid development of electronic manufacturing processes towards high-density integration and micro-nano precision, electronic products, represented by semiconductor chips, micro-circuit boards, and precision electronic components, are placing higher demands on cleaning processes. Traditional cleaning agents mostly use halogenated hydrocarbons and alkanes as organic solvents, which, while possessing good detergency capabilities, have significant drawbacks such as excessive volatile organic compound (VOC) emissions, flammability, explosiveness, and toxic residues.

[0003] Water-based cleaning agents mainly consist of surfactants, detergent additives, and corrosion inhibitors, and have become a widely used type of cleaning agent in recent years. Although water-based cleaning technology has made some progress in recent years, it still faces key technical bottlenecks: ① The surfactant compound system has insufficient removal efficiency for pollutants; ② Improper pH adjustment of the cleaning agent can easily lead to corrosion of metal contacts or swelling of polymer materials. Therefore, developing a water-based cleaning system that combines high cleaning efficiency, material compatibility, and environmental friendliness has become a pressing technical challenge for the industry. Summary of the Invention

[0004] This invention provides an aqueous cleaning agent that has high cleaning performance and does not cause metal pitting corrosion or polymer swelling.

[0005] A water-based cleaning agent for electronic products comprises: 5-10 wt% surfactant, 3-5 wt% N-methylpyrrolidone, 10-13% ether, 0.1-0.5 wt% corrosion inhibitor, 0.3-1 wt% complexing agent, 2-6 wt% pH adjuster, and water to make up to 100%.

[0006] Preferably, the water-based cleaning agent for electronic products comprises: 8 wt% surfactant, 4 wt% N-methylpyrrolidone, 11% ether, 0.2 wt% corrosion inhibitor, 0.5 wt% complexing agent, 2 wt% pH adjuster, and water to make up to 100%.

[0007] The surfactant is selected from at least two of fatty alcohol polyoxyethylene ether, polyether gemini surfactant, Dynol 604, Surfynol 465, sodium dodecyl sulfate, Surfynol 420, and Surfynol 440.

[0008] Preferably, the surfactant is a polyether gemini surfactant, Dynol 604, and Surfynol 465, and the weight ratio of the polyether gemini surfactant, Dynol 604, and Surfynol 465 is 4:3:1.

[0009] Gemini surfactants are a new type of surfactant composed of two traditional single-chain surfactant molecules covalently linked by a spacer.

[0010] The preparation method of the polyether gemini surfactant includes the following steps:

[0011] S1. Mix 0.1-0.22 mol of a hydroxyphenyl compound, 250 g of 1,2-dichloroethane, and 0.22 mol of concentrated nitric acid and react for 2-5 h. Then allow the mixture to stand and separate the liquid to obtain the lower organic phase. Wash and remove the solvent, and dry under vacuum to obtain intermediate product 1.

[0012] The hydroxyphenyl compound is selected from at least one of hexafluorobisphenol A (CAS: 1478-61-1), N-(4-hydroxyphenyl)-octadecanoamide, 4,4'-diamino-4"-hydroxytriphenylmethane, 3-[(3R,4R)-4-(3-hydroxyphenyl)hexane-3-yl]phenol, and 2,2-bis(4-hydroxyphenyl)propane.

[0013] The concentrated nitric acid has a mass fraction of 68%, and the washing is performed with a NaOH aqueous solution. The mass fraction of the NaOH aqueous solution is not limited and can be 0.5-10%.

[0014] S2. Mix 0.1 mol polyol ether, 0.2 mol N,N-dimethylformamide, and 2 mol toluene, and add 0.15-0.18 mol sulfoxide dropwise. After the addition is complete, react at 70-90℃ for 20-36 h. Then, add the mixture dropwise to 150.0 g of water, allow it to stand, separate the liquid and obtain the upper organic phase. After removing the solvent, dry it under vacuum to obtain intermediate product 2.

[0015] The polyol ether is selected from at least one of polypropylene glycol monomethyl ether-400, polypropylene glycol monomethyl ether-1000, polyethylene glycol dimethyl ether-100, polyethylene glycol dimethyl ether-350, and polyethylene glycol dimethyl ether-1000.

[0016] S3. React 0.1 mol of intermediate product 1, 0.25 mol of intermediate product 2, 0.25 mol of anhydrous potassium carbonate, and 120.0 g of N,N-dimethylformamide at 120-150 °C for 20-36 h. Then cool and filter under vacuum, remove the solvent from the filtrate under reduced pressure, add toluene for extraction, then wash and remove the toluene, and dry under vacuum to obtain the gemini surfactant. Wash with NaOH aqueous solution; the mass fraction of NaOH aqueous solution is not limited and can be 0.5-10%.

[0017] The Dynol 604 mentioned is from Evonik, a German company.

[0018] Surfynol 465 is a twin-star nonionic surfactant based on alkynyl diol technology, branded by Evonik Industries, Germany.

[0019] The polyether gemini surfactants described in this invention possess a unique "gemini structure" (two hydrophilic groups and two hydrophobic groups), which significantly reduces surface tension. Even at low concentrations, they can rapidly wet the surface of electronic components and effectively penetrate micron-level gaps (such as BGA solder joints and pin gaps) to remove flux residues, fingerprints, grease, and dust. Dynol 604 and Surfynol 465 further reduce dynamic surface tension and enhance wettability on low surface energy materials (such as plastics and silicone) by forming steric hindrance through the alkyne and hydroxyl groups in their molecules.

[0020] In particular, when the weight ratio of polyether gemini surfactant, Dynol 604, and Surfynol 465 is 4:3:1, the small size and branched structure of Dynol 604 and Surfynol 465 can be inserted into the micelle gaps formed by the polyether gemini, enhancing the ability to encapsulate tiny particles (such as metal oxides and dust) and preventing secondary deposition. Especially under high shear force conditions such as ultrasound, it can achieve "rapid penetration + long-lasting wetting".

[0021] The ether is selected from at least one of diethylene glycol monomethyl ether, ethylene glycol methyl ether, ethylene glycol monooctyl ether, ethylene glycol ethyl ether, and diethylene glycol methyl ethyl ether. Preferably, the ether is diethylene glycol monomethyl ether and ethylene glycol monoethyl ether, and the weight ratio of diethylene glycol monomethyl ether to ethylene glycol monoethyl ether is 1-3:1.

[0022] This cleaning agent, by selecting diethylene glycol monomethyl ether and ethylene glycol monoethyl ether, achieves a dynamic balance in its solubility for low- and high-polarity contaminants. The added N-methylpyrrolidone, through hydrogen bonding and dipole interactions, disrupts the cross-linking structure of high-molecular-weight contaminants, making it easier for diethylene glycol monomethyl ether and ethylene glycol monoethyl ether to penetrate and dissolve residues, especially for BGA underfill adhesive or PCB solder mask residue.

[0023] The corrosion inhibitor is at least one of benzotriazole, imidazoline surfactants, and Lan-826.

[0024] The complexing agent is sodium gluconate.

[0025] The pH adjuster is at least one of quaternary ammonium base, triethanolamine, and sodium carbonate.

[0026] The water-based cleaning agent of this invention is obtained by mixing raw materials.

[0027] The method of using the water-based cleaning agent is as follows: during ultrasonic cleaning, the object to be cleaned is immersed in an ultrasonic tank containing the water-based cleaning agent, and then rinsed with water once and twice.

[0028] Beneficial effects

[0029] The water-based cleaning agent described in this application can be used for cleaning electronic and electrical products. It not only provides excellent cleaning results but also ensures the high reliability of the cleaned electronic products, exhibiting good performance in electrical properties (no leakage or electromigration) and corrosion resistance (metal corrosion, plastic swelling, and ink blurring). The water-based cleaning agent has good low-foaming properties, and its surfactant compound system effectively removes contaminants. Furthermore, it does not cause corrosion of metal contacts or swelling of polymer materials; it is also non-flammable and non-explosive, safe to use, and environmentally friendly. Implementation

[0030] Example 1

[0031] A water-based cleaning agent comprises: 8 wt% surfactant, 4 wt% N-methylpyrrolidone, 11% ether, 0.2 wt% corrosion inhibitor, 0.5 wt% complexing agent, 2 wt% pH adjuster, and water to make up to 100%.

[0032] The surfactant is a polyether gemini surfactant, Dynol 604, and Surfynol 465, and the weight ratio of the polyether gemini surfactant, Dynol 604, and Surfynol 465 is 4:3:1.

[0033] The preparation method of the polyether gemini surfactant includes the following steps:

[0034] S1. Mix 0.1 mol of a hydroxyphenyl compound, 250 g of 1,2-dichloroethane, and 0.22 mol of concentrated nitric acid and react for 3 h. Then allow the mixture to stand and separate the liquid to obtain the lower organic phase. Wash and remove the solvent, and dry under vacuum to obtain intermediate product 1.

[0035] The hydroxyphenyl compound is hexafluorobisphenol A (CAS: 1478-61-1).

[0036] The concentrated nitric acid has a mass fraction of 68%, and the washing is performed with a NaOH aqueous solution, which has a mass fraction of 1%.

[0037] S2. Mix 0.1 mol polyol ether, 0.2 mol N,N-dimethylformamide, and 2 mol toluene, and add 0.15 mol sulfoxide dropwise. After the addition is complete, react at 70-90℃ for 24 h. Then, add the mixture dropwise to 150.0 g of water, allow it to stand, separate the liquid and obtain the upper organic phase. After removing the solvent, dry it under vacuum to obtain intermediate product 2.

[0038] The polyol ether is selected from polypropylene glycol monomethyl ether-400.

[0039] S3. 0.1 mol of intermediate product 1, 0.25 mol of intermediate product 2, 0.25 mol of anhydrous potassium carbonate, and 120.0 g of N,N-dimethylformamide were reacted at 130 °C for 30 h. The mixture was then cooled and filtered under vacuum. The solvent was removed from the filtrate under reduced pressure, and toluene was added for extraction. The mixture was then washed and the toluene was removed. The product was dried under vacuum to obtain the polyether gemini surfactant. The product was washed with a 1% NaOH aqueous solution.

[0040] Polyether gemini surfactant: 1H NMR (400MHz, DMSO-d6), δ: 7.86 (s, 2H, H5), 7.60 (d, J = 9.1Hz, 2H, H7), 7.55 (d, J = 9.1Hz, 2H, H6), 4.39 (t, J = 4.4Hz, 4H, H4), 3.80 (t, J = 4.5Hz, 4H, H3), 3.60–3.32 (m, 60H, H2), 3.25–3.18 (m, 6H, H1).

[0041] The Dynol 604 mentioned is from Evonik, a German company.

[0042] The Surfynol 465 mentioned is from Evonik, a German company.

[0043] The ethers are diethylene glycol monomethyl ether and ethylene glycol monoethyl ether, and the weight ratio of diethylene glycol monomethyl ether to ethylene glycol monoethyl ether is 2:1.

[0044] The corrosion inhibitor is benzotriazole.

[0045] The complexing agent is sodium gluconate.

[0046] The pH adjuster is triethanolamine.

[0047] Example 2

[0048] A water-based cleaning agent comprises: 8 wt% surfactant, 4 wt% N-methylpyrrolidone, 11% ether, 0.2 wt% corrosion inhibitor, 0.5 wt% complexing agent, 2 wt% pH adjuster, and water to make up to 100%.

[0049] The surfactant is a polyether gemini surfactant, Dynol 604, and Surfynol 465, and the weight ratio of the polyether gemini surfactant, Dynol 604, and Surfynol 465 is 4:3:1.

[0050] The preparation method of the polyether gemini surfactant includes the following steps:

[0051] S1. Mix 0.1 mol of a hydroxyphenyl compound, 250 g of 1,2-dichloroethane, and 0.22 mol of concentrated nitric acid and react for 3 h. Then allow the mixture to stand and separate the liquid to obtain the lower organic phase. Wash and remove the solvent, and dry under vacuum to obtain intermediate product 1.

[0052] The hydroxyphenyl compound is hexafluorobisphenol A (CAS: 1478-61-1).

[0053] The concentrated nitric acid has a mass fraction of 68%, and the washing is performed with a NaOH aqueous solution, which has a mass fraction of 1%.

[0054] S2. Mix 0.1 mol polyol ether, 0.2 mol N,N-dimethylformamide, and 2 mol toluene, and add 0.15 mol sulfoxide dropwise. After the addition is complete, react at 70-90℃ for 24 h. Then, add the mixture dropwise to 150.0 g of water, allow it to stand, separate the liquid and obtain the upper organic phase. After removing the solvent, dry it under vacuum to obtain intermediate product 2.

[0055] The polyol ether is selected from polyethylene glycol dimethyl ether-100.

[0056] S3. 0.1 mol of intermediate product 1, 0.25 mol of intermediate product 2, 0.25 mol of anhydrous potassium carbonate, and 120.0 g of N,N-dimethylformamide were reacted at 130 °C for 30 h. The mixture was then cooled and filtered under vacuum. The solvent was removed from the filtrate under reduced pressure, and toluene was added for extraction. The mixture was then washed and the toluene was removed. The product was dried under vacuum to obtain the gemini surfactant. The product was washed with a 1% NaOH aqueous solution.

[0057] The Dynol 604 mentioned is from Evonik, a German company.

[0058] The Surfynol 465 mentioned is from Evonik, a German company.

[0059] The ethers are diethylene glycol monomethyl ether and ethylene glycol monoethyl ether, and the weight ratio of diethylene glycol monomethyl ether to ethylene glycol monoethyl ether is 2:1.

[0060] The corrosion inhibitor is benzotriazole.

[0061] The complexing agent is sodium gluconate.

[0062] The pH adjuster is triethanolamine.

[0063] Example 3

[0064] A water-based cleaning agent comprises: 8 wt% surfactant, 4 wt% N-methylpyrrolidone, 11% ether, 0.2 wt% corrosion inhibitor, 0.5 wt% complexing agent, 2 wt% pH adjuster, and water to make up to 100%.

[0065] The surfactant is a polyether gemini surfactant, Dynol 604, and Surfynol 465, and the weight ratio of the polyether gemini surfactant, Dynol 604, and Surfynol 465 is 3:4:1.

[0066] The preparation method of the polyether gemini surfactant includes the following steps:

[0067] S1. Mix 0.1 mol of a hydroxyphenyl compound, 250 g of 1,2-dichloroethane, and 0.22 mol of concentrated nitric acid and react for 3 h. Then allow the mixture to stand and separate the liquid to obtain the lower organic phase. Wash and remove the solvent, and dry under vacuum to obtain intermediate product 1.

[0068] The hydroxyphenyl compound is hexafluorobisphenol A (CAS: 1478-61-1).

[0069] The concentrated nitric acid has a mass fraction of 68%, and the washing is performed with a NaOH aqueous solution, which has a mass fraction of 1%.

[0070] S2. Mix 0.1 mol polyol ether, 0.2 mol N,N-dimethylformamide, and 2 mol toluene, and add 0.15 mol sulfoxide dropwise. After the addition is complete, react at 70-90℃ for 24 h. Then, add the mixture dropwise to 150.0 g of water, allow it to stand, separate the liquid and obtain the upper organic phase. After removing the solvent, dry it under vacuum to obtain intermediate product 2.

[0071] The polyol ether is selected from polypropylene glycol monomethyl ether-400.

[0072] S3. 0.1 mol of intermediate product 1, 0.25 mol of intermediate product 2, 0.25 mol of anhydrous potassium carbonate, and 120.0 g of N,N-dimethylformamide were reacted at 130 °C for 30 h. The mixture was then cooled and filtered under vacuum. The solvent was removed from the filtrate under reduced pressure, and toluene was added for extraction. The mixture was then washed and the toluene was removed. The product was dried under vacuum to obtain the gemini surfactant. The product was washed with a 1% NaOH aqueous solution.

[0073] The Dynol 604 mentioned is from Evonik, a German company.

[0074] The Surfynol 465 mentioned is from Evonik, a German company.

[0075] The ethers are diethylene glycol monomethyl ether and ethylene glycol monoethyl ether, and the weight ratio of diethylene glycol monomethyl ether to ethylene glycol monoethyl ether is 2:1.

[0076] The corrosion inhibitor is benzotriazole.

[0077] The complexing agent is sodium gluconate.

[0078] The pH adjuster is triethanolamine.

[0079] Example 4

[0080] A water-based cleaning agent comprises: 8 wt% surfactant, 4 wt% N-methylpyrrolidone, 11% ether, 0.2 wt% corrosion inhibitor, 0.5 wt% complexing agent, 2 wt% pH adjuster, and water to make up to 100%.

[0081] The surfactant is a polyether gemini surfactant, Dynol 604, and Surfynol 465, and the weight ratio of the polyether gemini surfactant, Dynol 604, and Surfynol 465 is 4:3:1.

[0082] The preparation method of the polyether gemini surfactant includes the following steps:

[0083] S1. Mix 0.1 mol of a hydroxyphenyl compound, 250 g of 1,2-dichloroethane, and 0.22 mol of concentrated nitric acid and react for 3 h. Then allow the mixture to stand and separate the liquid to obtain the lower organic phase. Wash and remove the solvent, and dry under vacuum to obtain intermediate product 1.

[0084] The hydroxyphenyl compound is hexafluorobisphenol A (CAS: 1478-61-1).

[0085] The concentrated nitric acid has a mass fraction of 68%, and the washing is performed with a NaOH aqueous solution, which has a mass fraction of 1%.

[0086] S2. Mix 0.1 mol polyol ether, 0.2 mol N,N-dimethylformamide, and 2 mol toluene, and add 0.15 mol sulfoxide dropwise. After the addition is complete, react at 70-90℃ for 24 h. Then, add the mixture dropwise to 150.0 g of water, allow it to stand, separate the liquid and obtain the upper organic phase. After removing the solvent, dry it under vacuum to obtain intermediate product 2.

[0087] The polyol ether is selected from polypropylene glycol monomethyl ether-400.

[0088] S3. 0.1 mol of intermediate product 1, 0.25 mol of intermediate product 2, 0.25 mol of anhydrous potassium carbonate, and 120.0 g of N,N-dimethylformamide were reacted at 130 °C for 30 h. The mixture was then cooled and filtered under vacuum. The solvent was removed from the filtrate under reduced pressure, and toluene was added for extraction. The mixture was then washed and the toluene was removed. The product was dried under vacuum to obtain the gemini surfactant. The product was washed with a 1% NaOH aqueous solution.

[0089] The Dynol 604 mentioned is from Evonik, a German company.

[0090] The Surfynol 465 mentioned is from Evonik, a German company.

[0091] The ether is diethylene glycol monomethyl ether.

[0092] The corrosion inhibitor is benzotriazole.

[0093] The complexing agent is sodium gluconate.

[0094] The pH adjuster is triethanolamine.

[0095] Example 5

[0096] A water-based cleaning agent comprises: 8 wt% surfactant, 15% ether, 0.2 wt% corrosion inhibitor, 0.5 wt% complexing agent, 2 wt% pH adjuster, and water to make up to 100%.

[0097] The surfactant is a polyether gemini surfactant, Dynol 604, and Surfynol 465, and the weight ratio of the polyether gemini surfactant, Dynol 604, and Surfynol 465 is 4:3:1.

[0098] The preparation method of the polyether gemini surfactant includes the following steps:

[0099] S1. Mix 0.1 mol of a hydroxyphenyl compound, 250 g of 1,2-dichloroethane, and 0.22 mol of concentrated nitric acid and react for 3 h. Then allow the mixture to stand and separate the liquid to obtain the lower organic phase. Wash and remove the solvent, and dry under vacuum to obtain intermediate product 1.

[0100] The hydroxyphenyl compound is hexafluorobisphenol A (CAS: 1478-61-1).

[0101] The concentrated nitric acid has a mass fraction of 68%, and the washing is performed with a NaOH aqueous solution, which has a mass fraction of 1%.

[0102] S2. Mix 0.1 mol polyol ether, 0.2 mol N,N-dimethylformamide, and 2 mol toluene, and add 0.15 mol sulfoxide dropwise. After the addition is complete, react at 70-90℃ for 24 h. Then, add the mixture dropwise to 150.0 g of water, allow it to stand, separate the liquid and obtain the upper organic phase. After removing the solvent, dry it under vacuum to obtain intermediate product 2.

[0103] The polyol ether is selected from polypropylene glycol monomethyl ether-400.

[0104] S3. 0.1 mol of intermediate product 1, 0.25 mol of intermediate product 2, 0.25 mol of anhydrous potassium carbonate, and 120.0 g of N,N-dimethylformamide were reacted at 130 °C for 30 h. The mixture was then cooled and filtered under vacuum. The solvent was removed from the filtrate under reduced pressure, and toluene was added for extraction. The mixture was then washed and the toluene was removed. The product was dried under vacuum to obtain the gemini surfactant. The product was washed with a 1% NaOH aqueous solution.

[0105] The Dynol 604 mentioned is from Evonik, a German company.

[0106] The Surfynol 465 mentioned is from Evonik, a German company.

[0107] The ethers are diethylene glycol monomethyl ether and ethylene glycol monoethyl ether, and the weight ratio of diethylene glycol monomethyl ether to ethylene glycol monoethyl ether is 2:1.

[0108] The corrosion inhibitor is benzotriazole.

[0109] The complexing agent is sodium gluconate.

[0110] The pH adjuster is triethanolamine.

[0111] Performance testing and data

[0112] (1) Surface insulation resistance test after cleaning

[0113] Fifteen comb-shaped electrodes were selected for testing. The electrodes were manually soldered using common flux. After soldering, the electrodes were ultrasonically cleaned at room temperature for 30 minutes in aqueous cleaning agents containing those from Examples 1-5, respectively, followed by rinsing with water once and then twice. Each example used three comb-shaped electrodes, and the electrodes conformed to the IPC-B-24 standard.

[0114] The prepared comb-shaped electrodes were soldered with leads at the terminals and then placed in a test chamber at 85°C and 85% RH. A 50V DC voltage was applied between the electrodes for a damp heat test. The insulation resistance values ​​were tested at 24h, 96h, and 168h, with a test voltage of -100V and the bias voltage removed during the test. The surface insulation resistance data are shown in the table below (the test data for each example is the average of 5 pieces).

[0115] The surface insulation resistance of the comb-shaped electrodes before cleaning after manual soldering was 7.8 x 10⁻⁶. 7 The unit is Ω.

[0116] 24h 96h 168h Example 1 <![CDATA[8.0x10 8 ]]> <![CDATA[2.6x10 9 ]]> <![CDATA[5.3x10 9 ]]> Example 2 <![CDATA[2.3x10 8 ]]> <![CDATA[3.7x10 8 ]]> <![CDATA[9.6x10 8 ]]> Example 3 <![CDATA[8.8x10 7 ]]> <![CDATA[1.8x10 8 ]]> <![CDATA[4.3x10 8 <!-- 6 -->]]> Example 4 <![CDATA[2.8x10 8 ]]> <![CDATA[5.6x10 8 ]]> <![CDATA[2.7x10 9 ]]> Example 5 <![CDATA[2.5x10 8 ]]> <![CDATA[4.7x10 8 ]]> <![CDATA[1.1x10 9 ]]>

[0117] The cleaning effect of the cleaning agent and its compatibility with other electronic components were evaluated by testing the surface insulation resistance of the test board after cleaning (no leakage or low resistance was observed after cleaning). It can be seen that the surface insulation resistance value of Example 1 was the highest after 24h, 96h, and 168h.

[0118] (2) Metal corrosion test

[0119] Fifteen copper sheets were selected for testing. The copper sheets were electrolytic copper with a purity greater than 99.9%; three copper sheets were used for each example.

[0120] The cleaned copper sheet was completely immersed in a test tube containing the water-based cleaning agent of Examples 1-5. The test tube was then placed in a water bath at 100°C for 4 hours. The corrosion on the surface of the copper sheet was then observed using an optical microscope.

[0121] (3) PCB corrosion test

[0122] Fifteen PCBs were selected for testing. The PCBs contained green solder mask and printed ink characters; three PCBs were used for each embodiment.

[0123] The cleaned PCB board was completely immersed in a test tube containing the water-based cleaning agent from Examples 1-5. After being placed at 25°C for 48 hours, the green solder mask on the PCB was examined with an optical microscope to check for discoloration, corrosion, swelling, or other phenomena, and to check whether the printed ink characters were clear.

[0124] copper sheet PCB board Example 1 No color change No discoloration, swelling or other adverse phenomena. Example 2 No color change No discoloration, swelling or other adverse phenomena. Example 3 No color change No discoloration, swelling or other adverse phenomena. Example 4 No color change No discoloration, swelling or other adverse phenomena. Example 5 No color change No discoloration, swelling or other adverse phenomena.

[0125] (4) Ion contaminant testing

[0126] The cleaned components were tested for contaminants using an ion contamination tester. The residues on the components were cleaned into the test solution in a closed loop. The test solution was a 75% isopropanol aqueous solution by volume.

[0127] <![CDATA[NaCl / cm 2 ]]> Example 1 0.53μg Example 2 1.67μg Example 3 2.78μg Example 4 0.91μg Example 5 1.37μg

[0128] 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 them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A water-based cleaning agent, characterized in that, The components include: 5-10 wt% surfactant, 3-5 wt% N-methylpyrrolidone, 10-13% ether, 0.1-0.5 wt% corrosion inhibitor, 0.3-1 wt% complexing agent, 2-6 wt% pH adjuster, and water to make up to 100%. The surfactant is selected from at least two of fatty alcohol polyoxyethylene ether, polyether gemini surfactant, Dynol 604, Surfynol 465, sodium dodecyl sulfate, Surfynol 420, and Surfynol 440.

2. The water-based cleaning agent as described in claim 1, characterized in that, The water-based cleaning agent for electronic products comprises: 8 wt% surfactant, 4 wt% N-methylpyrrolidone, 11% ether, 0.2 wt% corrosion inhibitor, 0.5 wt% complexing agent, 2 wt% pH adjuster, and water to make up to 100%.

3. The water-based cleaning agent as described in claim 1, characterized in that, The ether is selected from at least one of diethylene glycol monomethyl ether, ethylene glycol methyl ether, ethylene glycol monooctyl ether, ethylene glycol ethyl ether, and diethylene glycol methyl ethyl ether.

4. The water-based cleaning agent as described in claim 3, characterized in that, The ethers are diethylene glycol monomethyl ether and ethylene glycol monoethyl ether, and the weight ratio of diethylene glycol monomethyl ether to ethylene glycol monoethyl ether is 1-3:

1.

5. The aqueous cleaning agent as described in claim 1, characterized in that, The corrosion inhibitor is at least one of benzotriazole, imidazoline surfactants, and Lan-826.

6. The aqueous cleaning agent as described in claim 5, characterized in that, The corrosion inhibitor is benzotriazole.

7. The aqueous cleaning agent as described in claim 1, characterized in that, The complexing agent is sodium gluconate.

8. The aqueous cleaning agent as described in claim 1, characterized in that, The pH adjuster is at least one of quaternary ammonium base, triethanolamine, and sodium carbonate.

9. A method for preparing an aqueous cleaning agent as described in any one of claims 1-8, characterized in that, The components are mixed evenly to obtain the final product.

10. A method of use, characterized in that, During ultrasonic cleaning, the object to be cleaned is immersed in an ultrasonic tank containing an aqueous cleaning agent as described in any one of claims 1-8 for ultrasonic cleaning, and then rinsed with primary and secondary water.