Dry and wet film tank cleaning agent as well as preparation method and application thereof

Abstract

The invention discloses a dry and wet membrane tank cleaning agent as well as a preparation method and application thereof. The dry and wet membrane tank cleaning agent comprises the following components: sulfuric acid, ferrous sulfate, phenolsulfonic acid, citric acid, sodium dodecyl benzene sulfonate, hydrogen peroxide and water. According to the invention, an advanced oxidation method is adopted to replace acid washing or alkali washing in the traditional technology for the first time, and the produced tank cleaning agent has extremely strong oxidation capacity, can effectively oxidize organic matters, and is suitable for dry film and green paint development processes in the PCB processing process; precipitated solids can be effectively removed, oily substances and intractable high polymer residues in dry films and green paint tanks can be removed, and the cleaning effect is very ideal. And regular tank cleaning can effectively ensure production quality and prolong the service life of instruments and equipment.

Description

Technical Field

[0001] This invention belongs to the field of printed circuit board processing technology, specifically relating to a dry film / ink developing tank cleaning agent for printed circuit boards, its preparation method, and its application. Background Technology

[0002] In the production of printed circuit boards (PCBs), the circuit and solder mask processes involve steps such as film application (or screen printing), alignment, exposure, and development to transfer the pattern from the photographic substrate to the PCB surface. The development step is completed in a developing tank containing developing solution. Commonly used developing solutions are 1-3% anhydrous sodium carbonate solutions, with a developing temperature of 30-40°C. The developing temperature may vary slightly depending on the dry film or ink used. During development, the active groups in the unexposed areas react with hydroxide ions to form water-soluble substances that dissolve in the developing solution. Meanwhile, the exposed areas undergo polymerization under light to form alkali-insoluble polymers, which remain on the circuit board, completing the pattern creation process.

[0003] The developing process produces dry film or ink residue, broken film, and photosensitizers from dry film decomposition, forming blue or yellow residues that remain suspended in the developing solution. As production time increases, these residues and other impurities adhere to rollers, nozzles, dead corners of the tank, and tank walls. In subsequent processing, these stains can then stick to the PCB board surface, causing open circuits or interconnections, adversely affecting subsequent processes such as electroless gold and tin plating. Therefore, regular cleaning and maintenance of the developing tank are necessary. These residues, contaminants, and other impurities are mainly high-molecular polymers, such as epoxy resin, acrylate, and polyurethane, as well as carbonate ions introduced by the developing solution. These carbonate ions react with calcium and magnesium ions in the water to form carbonate precipitates.

[0004] Commonly used methods for cleaning developing tanks include alkaline washing, acid washing, and two-component cleaning agents. Alkaline cleaning agents are effective at removing residual adhesives and oil stains, but their effectiveness against high molecular weight polymers, especially those that have already cross-linked and solidified, is poor, and their removal of carbonate precipitates is also ineffective. Cleaning typically requires 6-8 hours. CN102131328A discloses an alkaline cleaning agent, whose components are caustic soda flakes, a sterilizing agent, and methanol. Its main component is caustic soda flakes, which are effective at removing oily dirt but cannot remove stubborn high molecular weight polymer residues. Acidic cleaning agents are mainly composed of acetic acid. Acidic cleaning agents have a certain removal effect on dry film residues and carbonate precipitates, but their removal effect on oil stains and high molecular weight polymer residues is not ideal and their efficiency is low. Cleaning typically requires 4-6 hours, and acetic acid has a strong pungent odor that can cause discomfort to operators. Based on alkaline and acidic cleaning agents, technicians have introduced a two-component cleaning agent, also known as AB type cleaning agent. However, the two-component cleaning agent increases the operation steps, making the process cumbersome. It requires on-site preparation and dissolution, and the efficiency is relatively low, usually taking 8 to 10 hours.

[0005] To address the aforementioned issues, technicians attempted to adjust the cleaning agent's effectiveness using a combination of acids, organic solvents, and surfactants. CN102757871A discloses a PCB dry film developing tank cleaning agent and its preparation method. This patent classifies it as an acidic cleaning agent, with main components being acids, solubilizers, and surfactants. The acids include a certain amount of acetic acid with a strong, pungent odor. The solubilizer is a combination of ethylene glycol monobutyl ether and ethylene glycol ethyl ether. The cleaning time is approximately 2 hours, and the dry film residue dissolution rate is 90%. CN103923514A discloses a PCB developing tank cleaning solution and a method for cleaning the developing tank using this solution. This patent is similar to CN102757871A, with the main difference being the use of ethylene glycol butyl ether instead of the combination of ethylene glycol monobutyl ether and ethylene glycol ethyl ether. According to this patent, it has a good effect on removing unexposed ink stains, but it does not explain its effect on removing cured polymer residues. The cleaning time is approximately 2 hours. CN106434011A discloses a cleaning agent for developing tanks in PCB manufacturing processes. This patent also belongs to the category of acidic cleaning agents, differing from the aforementioned two patents mainly in that its solubilizer is polyethylene glycol. CN109234036A discloses an environmentally friendly cleaning agent for developing tanks, its preparation method, and its usage method. This patent also belongs to the category of acidic cleaning agents, differing from the aforementioned three patents mainly in its solubilizer, which is also an alcohol and ether. CN111019430A discloses a cleaning agent for PCB developing dry film / ink and its usage method. This patent also belongs to the category of acidic cleaning agents, similar to the aforementioned four patents, with the main difference being that the solubilizer in this patent is a 1:1 mass ratio mixture of ethylene glycol and ethylene glycol ethyl ether. All of these patents are based on acetic acid, with other inorganic acids added to reduce the amount of acetic acid used in order to reduce the irritating odor. However, this only improves the situation to a certain extent and does not fundamentally solve the problem. On the other hand, these patents use organic solvents to address the problem of oil stains and stubborn polymer residues, but the actual cleaning effect is not ideal. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a dry / wet film cleaning agent. This agent uses advanced oxidation to oxidize and peel off oily substances and stubborn polymer residues adhering to rollers, nozzles, dead corners of the tank, and tank walls, thereby dispersing them in the tank solution. This cleaning agent is suitable for dry film and green paint developing processes in PCB manufacturing. Using this dry / wet film cleaning agent to clean the developing tank effectively removes precipitated solids and eliminates oily substances and stubborn polymer residues from the dry film and green paint tanks. Regular tank cleaning effectively ensures product quality and extends the lifespan of equipment.

[0007] This invention utilizes the Fenton reaction principle, where hydrogen peroxide and ferrous ions react under acidic conditions to generate highly oxidizing hydroxyl radicals. These hydroxyl radicals effectively oxidize oily substances and stubborn polymer residues in dry films and green paint tanks. The Fenton reaction is an inorganic chemical reaction, the core process of which involves the reaction of hydrogen peroxide (H₂O₂) with ferrous ions (Fe²⁺). 2+ Under acidic (sulfuric acid) conditions, the Fenton reaction generates highly oxidizing hydroxyl radicals (·OH), which are used to oxidize organic matter. In this reaction, a ferrous ion is oxidized to a ferric ion by a hydrogen peroxide molecule, which then decomposes into a hydroxyl radical and a hydroxide ion. The ferric ion is subsequently reduced back to ferrous ions by another hydrogen peroxide molecule. The hydrogen peroxide molecule then decomposes into a superoxide radical and a hydrogen ion. Therefore, the overall reaction involves the continuous decomposition of hydrogen peroxide molecules, generating hydroxyl radicals, superoxide radicals, and water molecules. The generated hydroxyl radicals have extremely strong oxidizing power and can effectively oxidize organic matter. The Fenton reaction can be used to degrade recalcitrant organic pollutants.

[0008] The objective of this invention is achieved through the following technical solution: This invention provides a wet and dry membrane cleaning agent, comprising the following components: sulfuric acid, ferrous sulfate, phenol sulfonic acid, citric acid, sodium dodecylbenzene sulfonate, hydrogen peroxide, and water.

[0009] This invention provides a method for preparing a dry / wet film cleaning agent, comprising the following steps: Under room temperature and continuous stirring conditions, sulfuric acid, ferrous sulfate, phenol sulfonic acid, citric acid, sodium dodecylbenzene sulfonate, and hydrogen peroxide are added to water, and finally the volume is adjusted with water to obtain the dry and wet film cleaning agent.

[0010] Furthermore, the volume of sulfuric acid (50% by mass) added to each liter of cleaning agent is 90-110 mL; Furthermore, the mass of ferrous sulfate added to each liter of cleaning agent is 0.8~1.2g; Furthermore, the volume of phenolsulfonic acid added to each liter of cleaning agent is 4.5~5.5 mL; Furthermore, the mass of citric acid added to each liter of cleaning agent is 7.5~8.5g; Furthermore, the mass of sodium dodecylbenzenesulfonate added to each liter of cleaning agent is 0.24~0.26g; Furthermore, the volume of hydrogen peroxide (50% by mass) added to each liter of cleaning agent is 20-30 mL.

[0011] This invention also provides a method for using the aforementioned dry and wet film cleaning agent in the cleaning process of the dry film and green paint development process in PCB manufacturing. Specifically, it includes the following steps: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 8-10 minutes, and then drain completely; (3) Add an appropriate amount of cleaning agent according to the volume of the developing tank and soak for 8-12 minutes; then turn on the circulation pump and circulate and wash for 55-65 minutes. After that, drain the cleaning agent completely and use a high-pressure gun to rinse all corners of the tank. Parts that cannot be reached by the chemical solution (i.e., dry and wet film cleaning agent) can be wiped clean with a cloth dipped in the chemical solution. (4) Wash with 2%~5% sodium carbonate solution or potassium carbonate solution for 8~10 minutes and then discharge; (5) Rinse the developing tank with tap water for 15-50 minutes.

[0012] This invention provides a wet and dry film cleaning agent, the key components of which are ferrous sulfate, hydrogen peroxide, and acid. It employs the Fenton reaction principle, with the core process being the reaction of hydrogen peroxide (H₂O₂) with ferrous ions (Fe²⁺). 2+ When reacted under acidic conditions, it generates hydroxyl radicals (·OH) with strong oxidizing power, which can be used to oxidize recalcitrant organic compounds.

[0013] The present invention, by adopting the above technical solution, can achieve the following beneficial effects: 1. This invention is the first to use an advanced oxidation method to replace traditional acid or alkaline washing techniques. The resulting cleaning agent has extremely strong oxidizing power, effectively oxidizing organic matter. It is suitable for the dry film and green paint developing processes in PCB manufacturing. Using the dry and wet film cleaning agent of this invention to clean the developing tank can effectively remove precipitated solids and remove oily substances and stubborn polymer residues from the dry film and green paint tanks, with excellent cleaning results. Regular tank cleaning can effectively ensure production quality and extend the life of equipment.

[0014] 2. This cleaning agent has no irritating odor, is non-toxic, does not corrode equipment, and is safe and reliable.

[0015] 3. This cleaning agent does not require heating during use; it can be used for cleaning at room temperature, and the cleaning time is short.

[0016] 4. This cleaning agent does not contain nitrogen, chlorine, or other nitrogen-containing components, and its waste liquid and wastewater treatment is simple. Attached Figure Description

[0017] Figure 1 The image shows the effect of the cleaning agent of the present invention being used on a PCB company's production line. Detailed Implementation

[0018] To better understand the present invention, the present invention will be further described in detail below with reference to the embodiments, but the scope of protection of the present invention is not limited to the scope shown in the embodiments.

[0019] Example 1 Preparation of cleaning agent: Under continuous stirring, add 100 mL of sulfuric acid (50% by mass), 1.0 g of ferrous sulfate, 5.0 mL of phenolsulfonic acid, 8.0 g of citric acid, 0.25 g of sodium dodecylbenzenesulfonate, and 25 mL of hydrogen peroxide (50% by mass) to 500 mL of water. Finally, dilute to 1 L with water to obtain the cleaning agent.

[0020] Application Example 1 The cleaning agent of Example 1 was used for cleaning operations: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (3) Pour the cleaning solution into the developing tank to the working level and soak for 10 minutes; then turn on the circulation pump and circulate and wash for 60 minutes. Wipe the parts that cannot be reached by the cleaning solution with a cloth dipped in the solution and drain the cleaning solution completely. (4) Use a high-pressure gun to rinse all corners inside the tank; (5) Pour 3% anhydrous sodium carbonate solution into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (6) Pour tap water into the developing tank to the working level, circulate and rinse for 20 minutes, and then drain.

[0021] Example 2 Preparation of cleaning agent: Under continuous stirring, add 90 mL of sulfuric acid (50% by mass), 1.0 g of ferrous sulfate, 5.5 mL of phenol sulfonic acid, 7.5 g of citric acid, 0.25 g of sodium dodecylbenzene sulfonate, and 30 mL of hydrogen peroxide (50% by mass) to 500 mL of water. Finally, dilute to 1 L with water to obtain the cleaning agent.

[0022] Application Example 2 The cleaning agent of Example 2 was used for cleaning operations: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (3) Pour the cleaning solution into the developing tank to the working level and soak for 10 minutes; then turn on the circulation pump and circulate and wash for 60 minutes. Wipe the parts that cannot be reached by the cleaning solution with a cloth dipped in the solution and drain the cleaning solution completely. (4) Use a high-pressure gun to rinse all corners inside the tank; (5) Pour 4% anhydrous sodium carbonate solution into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (6) Pour tap water into the developing tank to the working level, circulate and rinse for 20 minutes, and then drain.

[0023] Example 3 Preparation of cleaning agent: Under continuous stirring, add 100 mL of sulfuric acid (50% by mass), 0.8 g of ferrous sulfate, 4.5 mL of phenolsulfonic acid, 7.5 g of citric acid, 0.26 g of sodium dodecylbenzenesulfonate, and 20 mL of hydrogen peroxide (50% by mass) to 500 mL of water. Finally, dilute to 1 L with water to obtain the cleaning agent.

[0024] Application Example 3 The cleaning agent of Example 3 was used for cleaning operations: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (3) Pour the cleaning solution into the developing tank to the working level and soak for 10 minutes; then turn on the circulation pump and circulate and wash for 60 minutes. Wipe the parts that cannot be reached by the cleaning solution with a cloth dipped in the solution and drain the cleaning solution completely. (4) Use a high-pressure gun to rinse all corners inside the tank; (5) Pour 5% anhydrous sodium carbonate solution into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (6) Pour tap water into the developing tank to the working level, circulate and rinse for 20 minutes, and then drain.

[0025] Example 4 Preparation of cleaning agent: Under continuous stirring, add 110 mL of sulfuric acid (50% by mass), 1.2 g of ferrous sulfate, 5.0 mL of phenolsulfonic acid, 8.5 g of citric acid, 0.24 g of sodium dodecylbenzenesulfonate, and 25 mL of hydrogen peroxide (50% by mass) to 500 mL of water. Finally, dilute to 1 L with water to obtain the cleaning agent.

[0026] Application Example 4 The cleaning agent from Example 4 was used for cleaning operations: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (3) Pour the cleaning solution into the developing tank to the working level and soak for 10 minutes; then turn on the circulation pump and circulate and wash for 60 minutes. Wipe the parts that cannot be reached by the cleaning solution with a cloth dipped in the solution and drain the cleaning solution completely. (4) Use a high-pressure gun to rinse all corners inside the tank; (5) Pour 2% anhydrous sodium carbonate solution into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (6) Pour tap water into the developing tank to the working level, circulate and rinse for 20 minutes, and then drain.

[0027] Example 5 Preparation of cleaning agent: Under continuous stirring, add 90 mL of sulfuric acid (50% by mass), 1.0 g of ferrous sulfate, 5.5 mL of phenol sulfonic acid, 7.5 g of citric acid, 0.25 g of sodium dodecylbenzene sulfonate, and 30 mL of hydrogen peroxide (50% by mass) to 500 mL of water. Finally, dilute to 1 L with water to obtain the cleaning agent.

[0028] Application Example 5 The cleaning agent from Example 5 was used for cleaning operations: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (3) Pour the cleaning solution into the developing tank to the working level and soak for 10 minutes; then turn on the circulation pump and circulate and wash for 60 minutes. Wipe the parts that cannot be reached by the cleaning solution with a cloth dipped in the solution and drain the cleaning solution completely. (4) Use a high-pressure gun to rinse all corners inside the tank; (5) Pour 3% anhydrous sodium carbonate solution into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (6) Pour tap water into the developing tank to the working level, circulate and rinse for 20 minutes, and then drain.

[0029] Example 6 Preparation of cleaning agent: Under continuous stirring, add 100 mL of sulfuric acid (50% by mass), 0.8 g of ferrous sulfate, 4.5 mL of phenolsulfonic acid, 8.0 g of citric acid, 0.26 g of sodium dodecylbenzenesulfonate, and 20 mL of hydrogen peroxide (50% by mass) to 500 mL of water. Finally, dilute to 1 L with water to obtain the cleaning agent.

[0030] Application Example 6 The cleaning agent of Example 6 was used for cleaning operations: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (3) Pour the cleaning solution into the developing tank to the working level and soak for 10 minutes; then turn on the circulation pump and circulate and wash for 60 minutes. Wipe the parts that cannot be reached by the cleaning solution with a cloth dipped in the solution and drain the cleaning solution completely. (4) Use a high-pressure gun to rinse all corners inside the tank; (5) Pour 4% anhydrous sodium carbonate solution into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (6) Pour tap water into the developing tank to the working level, circulate and rinse for 20 minutes, and then drain.

[0031] Example 7 Preparation of cleaning agent: Under continuous stirring, add 110 mL of sulfuric acid (50% by mass), 1.2 g of ferrous sulfate, 5.0 mL of phenolsulfonic acid, 8.5 g of citric acid, 0.24 g of sodium dodecylbenzenesulfonate, and 25 mL of hydrogen peroxide (50% by mass) to 500 mL of water. Finally, dilute to 1 L with water to obtain the cleaning agent.

[0032] Application Example 7 The cleaning agent of Example 7 was used for cleaning operations: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (3) Pour the cleaning solution into the developing tank to the working level and soak for 10 minutes; then turn on the circulation pump and circulate and wash for 60 minutes. Wipe the parts that cannot be reached by the cleaning solution with a cloth dipped in the solution and drain the cleaning solution completely. (4) Use a high-pressure gun to rinse all corners inside the tank; (5) Pour 5% anhydrous sodium carbonate solution into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (6) Pour tap water into the developing tank to the working level, circulate and rinse for 20 minutes, and then drain.

[0033] Example 8 Preparation of cleaning agent: Under continuous stirring, add 90 mL of sulfuric acid (50% by mass), 1.0 g of ferrous sulfate, 5.5 mL of phenol sulfonic acid, 7.5 g of citric acid, 0.25 g of sodium dodecylbenzene sulfonate, and 30 mL of hydrogen peroxide (50% by mass) to 500 mL of water. Finally, dilute to 1 L with water to obtain the cleaning agent.

[0034] Application Example 8 The cleaning agent of Example 8 was used for cleaning operations: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (3) Pour the cleaning solution into the developing tank to the working level and soak for 10 minutes; then turn on the circulation pump and circulate and wash for 60 minutes. Wipe the parts that cannot be reached by the cleaning solution with a cloth dipped in the solution and drain the cleaning solution completely. (4) Use a high-pressure gun to rinse all corners inside the tank; (5) Pour 3% anhydrous sodium carbonate solution into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (6) Pour tap water into the developing tank to the working level, circulate and rinse for 20 minutes, and then drain.

[0035] Example 9 Preparation of cleaning agent: Under continuous stirring, add 100 mL of sulfuric acid (50% by mass), 0.8 g of ferrous sulfate, 4.5 mL of phenolsulfonic acid, 8.0 g of citric acid, 0.26 g of sodium dodecylbenzenesulfonate, and 20 mL of hydrogen peroxide (50% by mass) to 500 mL of water. Finally, dilute to 1 L with water to obtain the cleaning agent.

[0036] Application Example 9 The cleaning agent of Example 9 was used for cleaning operations: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (3) Pour the cleaning solution into the developing tank to the working level and soak for 10 minutes; then turn on the circulation pump and circulate and wash for 60 minutes. Wipe the parts that cannot be reached by the cleaning solution with a cloth dipped in the solution and drain the cleaning solution completely. (4) Use a high-pressure gun to rinse all corners inside the tank; (5) Pour 4% anhydrous sodium carbonate solution into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (6) Pour tap water into the developing tank to the working level, circulate and rinse for 20 minutes, and then drain.

[0037] Example 10 Preparation of cleaning agent: Under continuous stirring, add 110 mL of sulfuric acid (50% by mass), 1.2 g of ferrous sulfate, 5.0 mL of phenolsulfonic acid, 8.5 g of citric acid, 0.24 g of sodium dodecylbenzenesulfonate, and 25 mL of hydrogen peroxide (50% by mass) to 500 mL of water. Finally, dilute to 1 L with water to obtain the cleaning agent.

[0038] Application Example 10 Cleaning operations were performed using the cleaning agent from Example 10: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (3) Pour the cleaning solution into the developing tank to the working level and soak for 10 minutes; then turn on the circulation pump and circulate and wash for 60 minutes. Wipe the parts that cannot be reached by the cleaning solution with a cloth dipped in the solution and drain the cleaning solution completely. (4) Use a high-pressure gun to rinse all corners inside the tank; (5) Pour 2% anhydrous sodium carbonate solution into the developing tank to the working level, circulate and rinse for 10 minutes, and then drain completely; (6) Pour tap water into the developing tank to the working level, circulate and rinse for 20 minutes, and then drain.

[0039] This invention is the first to employ an advanced oxidation method to replace traditional acid or alkaline washing techniques. The resulting cleaning agent possesses extremely strong oxidizing capabilities, effectively oxidizing organic matter. It is suitable for dry film and green paint development processes in PCB manufacturing. Using this invention's dry and wet film cleaning agent to clean the developing tank effectively removes precipitated solids and eliminates oily substances and stubborn polymer residues from dry film and green paint tanks. Regular tank cleaning effectively ensures production quality and extends the lifespan of equipment. A comparison of the cleaning agent's performance with commercially available cleaning agents on PCB production lines is provided below. Figure 1As shown, there are still obvious residues after cleaning with ordinary cleaning agents, while the cleaning effect of the cleaning agent of the present invention is very ideal, with almost no residue, and the rollers are as good as new after cleaning.

[0040] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A dry / wet film cleaning agent, characterized in that, It includes the following components: sulfuric acid, ferrous sulfate, phenol sulfonic acid, citric acid, sodium dodecylbenzene sulfonate, hydrogen peroxide, and water.

2. A method for preparing the dry / wet film cleaning agent as described in claim 1, characterized in that, The process includes the following steps: adding sulfuric acid, ferrous sulfate, phenol sulfonic acid, citric acid, sodium dodecylbenzene sulfonate, and hydrogen peroxide to water at room temperature and under continuous stirring, and finally adjusting the volume with water to obtain the wet and dry film cleaning agent.

3. The preparation method according to claim 2, characterized in that, The volume of sulfuric acid added to each liter of cleaning agent is 90-110 mL.

4. The preparation method according to claim 2, characterized in that, The mass of ferrous sulfate added to each liter of cleaning agent is 0.8~1.2g.

5. The preparation method according to claim 2, characterized in that, The volume of phenol sulfonic acid added to each liter of cleaning agent is 4.5~5.5 mL.

6. The preparation method according to claim 2, characterized in that, The amount of citric acid added per liter of cleaning agent is 7.5~8.5g.

7. The preparation method according to claim 2, characterized in that, The mass of sodium dodecylbenzenesulfonate added to each liter of cleaning agent is 0.24~0.26g.

8. The preparation method according to claim 2, characterized in that, The volume of hydrogen peroxide added to each liter of cleaning agent is 20-30 mL, and the mass percentage concentration of hydrogen peroxide is 50%.

9. The application of the dry / wet film cleaning agent as described in claim 1 in the cleaning process of the dry film and green paint development process in PCB manufacturing.

10. The application according to claim 9, characterized in that, Specifically, it includes the following steps: (1) Drain the developing waste liquid in the developing tank and clean the sediment at the bottom of the tank. (2) Pour tap water into the developing tank to the working level, circulate and rinse, and then drain completely; (3) Add an appropriate amount of cleaning agent according to the volume of the developing tank and soak it; then turn on the circulation pump to circulate and wash, drain the cleaning agent completely, use a high-pressure gun to rinse all corners of the tank, and wipe clean any parts that cannot be sprayed by the chemical solution with a cloth dipped in the chemical solution. (4) Discharge after circulating and washing with 2%~5% sodium carbonate solution or potassium carbonate solution; (5) The developing tank is rinsed with tap water and then discharged.

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