Acidic degreaser and preparation method thereof

Abstract

The invention discloses an acidic degreaser and a preparation method thereof, and relates to the technical field of printed circuit board surface treatment. The acidic degreasing agent is prepared from the following preparation raw materials in parts by weight: 20-35 parts of organic acid; 4-8 parts of inorganic acid; 3-6 parts of a corrosion inhibitor; 50 to 60 parts of a wetting agent; 3-6 parts of vermiculite powder; 10 to 17 parts of a surfactant; 6-10 parts of acid activated fruit shells; and 750 to 820 parts of deionized water. The acidic degreasing agent prepared by the invention has efficient and rapid degreasing efficiency, does not corrode the metal surface of the printed circuit board, is low in ammonia nitrogen content, conforms to the green and environment-friendly concept, and is suitable for the degreasing process of the printed circuit board.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of printed circuit board surface treatment, in particular to an acidic degreasing agent and a preparation method thereof. BACKGROUND

[0002] The acidic degreasing agent is a chemical preparation mainly composed of surfactants, corrosion inhibitors and penetrants, and is usually a colorless transparent liquid. In use, the acidic degreasing agent is added to the pickling solution, which has the dual functions of degreasing and derusting, slows down the corrosion of the acid solution to the metal, and is suitable for the pretreatment process of metal coating, electroplating and ceramic substrate production.

[0003] The substrate of the printed circuit board adopts a polyimide copper-clad plate. In the manufacturing process of the printed circuit board, in order to improve the corrosion resistance of the copper surface, a surface protective layer is formed on the copper surface through surface treatment, electroplating nickel gold, OSP, chemical tin plating or chemical nickel gold plating. Before the surface treatment, the printed circuit board is subjected to a degreasing process, which cleans the copper surface by removing grease, oxides, fingerprints and the like on the copper surface, so as to keep the copper surface clean and increase the wettability, thereby facilitating subsequent electroplating or chemical plating.

[0004] In the existing acidic degreasing agent, ammonium-containing compounds such as quaternary ammonium salt surfactants are often used as additives. However, these ammonium-containing compounds have high ammonia nitrogen content, and the wastewater after use can easily pollute the environment, which does not meet the environmental protection concept. SUMMARY

[0005] The present application aims to provide an acidic degreasing agent and a preparation method thereof. The acidic degreasing agent prepared by the present application has high and fast degreasing efficiency, does not corrode the metal surface of the printed circuit board, has low ammonia nitrogen content, meets the green environmental protection concept, and is suitable for the degreasing process of the printed circuit board.

[0006] The present application provides an acidic degreasing agent and a preparation method thereof, which adopts the following technical scheme: In a first aspect, the present application discloses an acidic degreasing agent, which comprises the following preparation raw materials in parts by weight: organic acid 20-35 parts; inorganic acid 4-8 parts; corrosion inhibitor 3-6 parts; wetting agent 50-60 parts; vermiculite powder 3-6 parts; surfactant 10-17 parts; acid-activated fruit shell 6-10 parts; and deionized water 750-820 parts.

[0007] Through the above technical scheme, the acidic activator of the present application achieves fast and efficient degreasing effect through the synergistic effect of organic acid, inorganic acid, corrosion inhibitor, wetting agent, vermiculite powder, surfactant, acid-activated fruit shell and deionized water in the degreasing process of the printed circuit board. At the same time, the raw material components of the present application have low ammonia nitrogen content, which meets the green environmental protection production requirements.

[0008] The complex of organic acid and inorganic acid is used to reduce the corrosion of the metal of the circuit board by adding a small amount of inorganic acid and corrosion inhibitor, the strong acidity of the inorganic acid is used to improve the oil removal effect, and the concentration of the organic acid in the system can be reduced; the wetting agent reduces the interfacial tension, so that the oil removal agent can wet and penetrate the surface of the circuit board; the surfactant can improve the stability of the oil removal agent system, and long-term oil removal effect can be achieved; the vermiculite powder as the filler can adsorb and flocculate the oil, and at the same time, the oil on the metal surface is stripped, so that the circuit board is not polluted again, and the clarity of the tank liquid can be maintained; the acid-activated nutshell can adsorb and intercept the oil through the porous structure, and at the same time, the acid-activated nutshell can be used to synergistically enhance the emulsification and dispersion capacity of the oil in the acidic environment.

[0009] Optionally, the vermiculite powder is modified vermiculite powder, and the modified vermiculite powder is prepared by the following steps: The vermiculite powder, dodecyl dimethyl betaine and solvent water are mixed and stirred to prepare a slurry, the obtained slurry is placed in a ball mill for grinding for 2-3 h, the sample taken out after grinding is subjected to centrifugation, filtration, repeated washing with deionized water, drying and sieving, and the sample with a particle size of 200-300 mesh is screened out to obtain the modified vermiculite powder.

[0010] By using the above technical solution, through the synergistic effect of intercalation modification and grinding activation, the anion and cation groups in the dodecyl dimethyl betaine are bonded with the interlayer cations and silicon-oxygen layers of the vermiculite respectively, the intercalation efficiency is improved, the oil adsorption sites are increased after crushing, the stability in the acidic environment and the adsorption of the oil are improved, and the oil removal effect is further improved.

[0011] Optionally, the weight ratio of the vermiculite powder, dodecyl dimethyl betaine and solvent water is 10:(1.5-2.3):(50-60).

[0012] By using the above technical solution, the intercalation effect is improved by using the vermiculite powder, dodecyl dimethyl betaine and solvent water in a proper ratio.

[0013] Optionally, the acid-activated nutshell is prepared by the following steps: The nutshell is crushed, and the nutshell with a particle size of 0.5-2 mm is screened out, washed with water and dried for standby use; Citric acid is used as an activator, and the citric acid is diluted with water to a volume concentration of 30%-50% to obtain an acid solution; The nutshell is immersed in the acid solution, the solid-liquid ratio is 1:5-1:8 (nutshell mass / acid solution volume), the water bath is heated to 60-80°C and stirred for 2-3 h, and after the end, the nutshell is repeatedly washed with water until the filtrate is neutral, and the acid-activated nutshell is obtained after drying.

[0014] By adopting the technical scheme, the impurities on the surface of the shell can be removed and the porosity can be increased after the citric acid activation treatment, the oil is physically adsorbed through the developed pore structure of the shell, and the stability of the shell in the acidic environment is improved.

[0015] Optionally, the shell is selected from one or more of walnut shell, coconut shell and apricot shell.

[0016] Optionally, the organic acid is a mixture of citric acid and tartaric acid, and the molar ratio of citric acid to tartaric acid is 3:1-4:1.

[0017] By adopting the technical scheme, through the appropriate proportion, the strong chelating ability of citric acid and the steric hindrance effect of tartaric acid are used to synergistically act on the oil layer on the surface of the circuit board metal, the molecular structure is destroyed and the dissolution is accelerated.

[0018] Optionally, the surfactant is a mixture of coconut diethanol amide and sorbitan fatty acid ester in a mass ratio of (1.1-1.4):1.

[0019] By adopting the technical scheme, the surfactant is selected, the surface activity is improved, the dispersity of the vermiculite powder and the acid-activated shell in the system is improved, the oil removal effect is improved, and the quaternary ammonium salt surfactant is not used, which is more environmentally friendly.

[0020] Optionally, the inorganic acid is selected from one or more of sulfuric acid with a mass concentration of 20% and hydrochloric acid with a mass concentration of 37%.

[0021] By adopting the technical scheme, the inorganic acid has strong acidity and can remove stubborn oil and oxides.

[0022] Optionally, the corrosion inhibitor is selected from one or more of beta-cyclal C, p-benzene formaldehyde, coconut oil alkyl alcohol amide phosphate, and the wetting agent is selected from one or more of lauryl polyoxyethylene ether and platycodon saponin.

[0023] In a second aspect, the application provides a preparation method of an acidic oil removal agent, comprising the following steps: The inorganic acid, the organic acid, the corrosion inhibitor, the vermiculite powder and the acid-activated shell are sequentially added to the deionized water and fully mixed to obtain a mixed solution A, and then heated to a temperature of 50-60℃. The wetting agent and the surfactant are added to the mixed solution A, and stirred for 2-3h at a stirring rate of 150-180r / min to obtain the acidic oil removal agent.

[0024] By adopting the technical scheme, the oil removal agent preparation method is simple, the production cost is low, and the enterprise production cost is reduced.

[0025] In summary, the present application has at least one of the following beneficial effects: 1. The acid activator of the present application, through the synergistic effect of organic acid, inorganic acid, corrosion inhibitor, wetting agent, vermiculite powder, surfactant, acid-activated nutshell and deionized water, is applied in the oil removal process of printed circuit board to achieve rapid and efficient oil removal effect. At the same time, the raw material component of the present application has low ammonia nitrogen content, which meets the green and environmentally friendly production requirements.

[0026] By compounding organic acid and inorganic acid, adding a small amount of inorganic acid and corrosion inhibitor to reduce corrosion of the metal circuit board, using the strong acidity of inorganic acid to improve the oil removal effect, the concentration of organic acid in the system can be reduced; the wetting agent reduces the interfacial tension, facilitating the wetting and penetration of the oil removal agent on the surface of the circuit board; the surfactant can improve the stability of the oil removal agent system, realizing long-term oil removal effect; the vermiculite powder as a filler can adsorb and flocculate oil, and at the same time strip the oil from the metal surface, avoiding recontamination of the circuit board and maintaining the clarity of the tank liquid; the acid-activated nutshell can adsorb and retain oil through its porous structure, and at the same time, the acid-activated nutshell can synergistically enhance the emulsification and dispersion ability of oil in the acidic environment.

[0027] 2. Through the synergistic effect of intercalation modification and grinding activation, the anion and cation groups in dodecyl dimethyl betaine are bonded with the interlayer cations and silicon-oxygen layers of vermiculite, respectively, improving the intercalation efficiency, increasing the oil adsorption sites after crushing, improving the stability in acidic environment and the adsorption of oil, and further improving the oil removal effect. DETAILED DESCRIPTION

[0028] The present application will be further described in detail below in combination with Examples 1-5 and Comparative Examples 1-2. In the examples of the present application, if the specific conditions are not specified in the examples, the conventional conditions or the conditions recommended by the manufacturer are used. If the manufacturer of the reagent or instrument is not specified, it is a conventional product that can be purchased on the market.

[0029] The vermiculite powder was purchased from Lingshou County Nan Yu Mineral Product Processing Factory, and the particle size of 200-300 mesh vermiculite powder was selected; The dodecyl dimethyl betaine was purchased from Shandong Xuxiang Chemical Co., Ltd., with model BS-12 and CAS number 683-10-3.

[0030] Preparation Example Preparation Example 1 The modified vermiculite powder was prepared by the following steps: Mix 10 parts of vermiculite powder with 1.5 parts of dodecyl dimethyl betaine, 50 parts of solvent water to prepare a slurry, and place the obtained slurry in a ball mill for grinding for 2 hours. After grinding, the sample taken out is centrifuged, filtered, washed repeatedly with deionized water, dried in an oven at 105°C, and sieved. The sample with a particle size of 200-300 mesh is screened to obtain modified vermiculite powder.

[0031] Preparation Example 2 The modified vermiculite powder is prepared by the following steps: Mix 10 parts of vermiculite powder with 2.3 parts of dodecyl dimethyl betaine, 60 parts of solvent water to prepare a slurry, and place the obtained slurry in a ball mill for grinding for 3 hours. After grinding, the sample taken out is centrifuged, filtered, washed repeatedly with deionized water, dried in an oven at 105°C, and sieved. The sample with a particle size of 200-300 mesh is screened to obtain modified vermiculite powder.

[0032] Preparation Example 3 The acid-activated nutshell is prepared by the following steps: The nutshell is crushed, and nutshell with a particle size of 0.5-2 mm is screened, washed with water, and dried for standby use. Citric acid is used as an activator, and the citric acid is diluted with water to a volume concentration of 30% to obtain an acid solution. The nutshell is immersed in the acid solution, and the solid-liquid ratio is 1:8 (nutshell mass / acid solution volume). The water bath is heated to 60°C and stirred for 3 hours. After completion, the nutshell is taken out and washed repeatedly with water until the filtrate is neutral. The acid-activated nutshell is obtained after drying.

[0033] Preparation Example 4 The acid-activated nutshell is prepared by the following steps: The nutshell is crushed, and nutshell with a particle size of 0.5-2 mm is screened, washed with water, and dried for standby use. Citric acid is used as an activator, and the citric acid is diluted with water to a volume concentration of 50% to obtain an acid solution. The nutshell is immersed in the acid solution, and the solid-liquid ratio is 1:5 (nutshell mass / acid solution volume). The water bath is heated to 80°C and stirred for 2 hours. After completion, the nutshell is taken out and washed repeatedly with water until the filtrate is neutral. The acid-activated nutshell is obtained after drying. Example

[0034] Example 1 An acidic oil removing agent, by weight, includes the following preparation raw materials: 20 parts of organic acid, specifically a mixture of citric acid and tartaric acid with a molar ratio of 3:1; 4 parts of inorganic acid, specifically 20% sulfuric acid by mass concentration; corrosion inhibitor 3 parts, specifically selected from beta-cyclocitral; wetting agent 50 parts, specifically selected from lauryl polyoxyethylene ether; vermiculite powder 3 parts; surfactant 10 parts, specifically selected from a mixture of 5.3 parts of cocodiethanolamide and 4.7 parts of sorbitan fatty acid ester; acid-activated nutshell 6 parts, specifically selected from the acid-activated nutshell prepared in Preparation Example 3, and the nutshell is walnut shell; deionized water 750 parts.

[0035] The preparation method of the acidic oil removal agent comprises the following steps: mineral acid, organic acid, corrosion inhibitor, vermiculite powder and acid-activated nutshell are sequentially added into deionized water and fully mixed to be uniform, and heated to a temperature of 50℃ to obtain a mixed solution A; wetting agent and surfactant are added into the mixed solution A, and stirred for a reaction time of 2h at a stirring rate of 180r / min to obtain the acidic oil removal agent.

[0036] Example 2 An acidic oil removal agent comprises the following preparation raw materials in parts by weight: organic acid 35 parts, specifically selected from a mixture of citric acid and tartaric acid, and the molar ratio of citric acid to tartaric acid is 4:1; mineral acid 8 parts, specifically selected from hydrochloric acid with a mass concentration of 37%; corrosion inhibitor 6 parts, specifically selected from p-xylylene; wetting agent 60 parts, specifically selected from platycodon saponin; vermiculite powder 6 parts; surfactant 17 parts, specifically selected from a mixture of 9.9 parts of cocodiethanolamide and 7.1 parts of sorbitan fatty acid ester; acid-activated nutshell 10 parts, specifically selected from the acid-activated nutshell prepared in Preparation Example 3, and the nutshell is coconut shell; deionized water 820 parts.

[0037] The preparation method of the acidic oil removal agent comprises the following steps: mineral acid, organic acid, corrosion inhibitor, vermiculite powder and acid-activated nutshell are sequentially added into deionized water and fully mixed to be uniform, and heated to a temperature of 60℃ to obtain a mixed solution A; wetting agent and surfactant are added into the mixed solution A, and stirred for a reaction time of 3h at a stirring rate of 150r / min to obtain the acidic oil removal agent.

[0038] Example 3 An acidic oil removal agent comprises the following preparation raw materials in parts by weight: organic acid 28 parts, specifically selected from a mixture of citric acid and tartaric acid, and the molar ratio of citric acid to tartaric acid is 3:1; Inorganic acid 6 parts, specifically selected from 20% mass concentration of sulfuric acid; Corrosion inhibitor 5 parts, specifically selected from coconut oil alkyl alcohol amide phosphate; Wetting agent 57 parts, specifically selected from 37 parts of lauryl polyoxyethylene ether and 20 parts of luffin; Vermiculite powder 4 parts; Surfactant 14 parts, specifically selected from a mixture of 7.9 parts of cocodiethanolamide and 6.1 parts of sorbitan fatty acid ester; acid-activated fruit shell 8 parts, specifically selected from the acid-activated fruit shell prepared in Preparation Example 4, and the fruit shell is apricot shell; Deionized water 790 parts.

[0039] The preparation method of the acidic oil removal agent comprises the following steps: The inorganic acid, organic acid, corrosion inhibitor, vermiculite powder and acid-activated fruit shell are sequentially added to the deionized water and fully mixed to obtain a mixed solution A, and then heated to a temperature of 55°C; The wetting agent and surfactant are added to the mixed solution A, and stirred for a reaction time of 2.5h at a stirring rate of 160r / min to obtain the acidic oil removal agent.

[0040] Example 4 The difference between this example and Example 1 is that the vermiculite powder in the raw materials of the acidic oil removal agent is different.

[0041] The vermiculite powder in this example is the modified vermiculite powder prepared in Preparation Example 1.

[0042] Example 5 The difference between this example and Example 1 is that the vermiculite powder in the raw materials of the acidic oil removal agent is different.

[0043] The vermiculite powder in this example is the modified vermiculite powder prepared in Preparation Example 2.

[0044] Comparative Example Comparative Example 1 The difference between this comparative example and Example 1 is that the acid-activated fruit shell in the raw materials of the acidic oil removal agent is different.

[0045] In this comparative example, no acid-activated fruit shell is added to the raw materials of the acidic oil removal agent.

[0046] Comparative Example 2 The difference between this comparative example and Example 1 is that the vermiculite powder in the raw materials of the acidic oil removal agent is different.

[0047] In this comparative example, no vermiculite powder is added to the raw materials of the acidic oil removal agent.

[0048] Performance test The following properties were detected for the acid activator prepared in Examples 1-5 and Comparative Examples 1-2, and the detection results were recorded.

[0049] The processed printed circuit board sample was cut into a 5 cm x 5 cm sample, and the corners were removed with sandpaper. The surface of the processed circuit board had contaminants such as oil stains, glue marks, grease, and oxidation points that were difficult to remove. The acid degreasing agent prepared above was used to treat the printed circuit board sample, and the specific process was as follows: the circuit board sample was immersed in the acid degreasing agent preheated to 30°C for 150 s, then washed with deionized water and ethanol for 60 s, and dried to obtain the degreased circuit board sample.

[0050] Detergent effect: whether there were oil stains, glue marks, grease, oxidation points, and other residues on the surface of the circuit board after treatment with the acid degreasing agent was observed, and the evaluation was performed according to a 10-point scale, with 10 points being the best and 0 points being the worst.

[0051] Corrosion resistance: whether there was metal corrosion on the surface of the circuit board after treatment with the acid degreasing agent was determined, and the evaluation was performed according to a 10-point scale, with 10 points being the best, indicating that there was no corrosion on the surface of the circuit board, and 0 points being the worst, indicating that there was a large amount of corrosion on the surface of the circuit board.

[0052] Ammonia nitrogen content: a small amount of acid degreasing agent was taken, and the ammonia nitrogen content was detected by the Nash reagent spectrophotometric method. The principle was that the alkaline solution of mercuric iodide and potassium iodide reacted with ammonia to form a light red-brown colloidal compound, which had strong absorption in the wavelength range of 410-425 nm.

[0053] Table 1 Test sample Oil removal effect Corrosion resistance Ammonia nitrogen content (mg / L) Example 1 10 10 24.3 Example 2 10 10 23.9 Example 3 10 10 24.7 Example 4 10 10 26.8 Example 5 10 10 27.1 Comparative Example 1 8 10 24.1 Comparative Example 2 7 10 23.5 According to the data in Table 1, the acid degreasing agent prepared in the present application, through the synergistic effect of organic acid, inorganic acid, corrosion inhibitor, wetting agent, vermiculite powder, surfactant, acid-activated nutshell, and deionized water, can obtain excellent degreasing effect after degreasing treatment of the printed circuit board, and there is no grease, oil stain, oxidation point, glue mark, and other stains on the surface of the circuit board. The circuit board shows excellent corrosion resistance, the acid degreasing agent can quickly wet and penetrate the surface of the circuit board, and will not cause corrosion to the metal surface of the circuit board. The ammonia nitrogen content of the acid degreasing agent is high, which meets the green and environmentally friendly production requirements.

[0054] Compared with the comparative example 1 and the comparative example 2 and the example 1, when the vermiculite powder and the acid-activated nutshell are absent in the raw material components of the acid degreaser, the degreasing effect of the degreaser is reduced, and there are stubborn oil stains, oxidation points and other residues on the surface of the circuit board. This is because in the acid degreaser, the addition of the acid-activated nutshell can produce a synergistic effect with the environment of the organic acid and the inorganic acid, improve the emulsification and dispersion ability of the oil, and at the same time use the physical adsorption ability of the acid-activated nutshell itself to adsorb the oil, and the degreasing is carried out through physical and chemical aspects; and the vermiculite powder itself has strong physical adsorption ability, can flocculate the oil, and cooperate with the stripping of the oil from the metal surface, so as to synergistically improve the degreasing effect and cleaning ability of the surface of the circuit board through multiple aspects.

[0055] The specific embodiment is only an explanation of the present application, and is not a limitation of the present application. Those skilled in the art can make modifications to the specific embodiment without creative contribution after reading the present specification, but as long as the present application is within the scope of the claims, it is protected by the patent law.

Claims

1. An acidic oil remover, characterized by comprising: 1) 10 to 50% by weight of an acid, The preparation raw materials include the following by weight parts: organic acid 20-35 parts; inorganic acid 4-8 parts; corrosion inhibitor 3-6 parts; wetting agent 50-60 parts; vermiculite powder 3-6 parts; surfactant 10-17 parts; acid-activated nutshell 6-10 parts; Deionized water 750-820 parts.

2. The acidic oil remover according to claim 1, characterized in that: The vermiculite powder is modified vermiculite powder, which is prepared by the following steps: The vermiculite powder is mixed with dodecyl dimethyl betaine and solvent water to form a slurry, and the obtained slurry is placed in a ball mill for grinding for 2-3 h. The sample taken out after grinding is centrifuged, filtered, repeatedly washed with deionized water, dried, and sieved to obtain a sample with a particle size of 200-300 mesh, thereby obtaining the modified vermiculite powder.

3. The acidic oil remover according to claim 2, characterized in that: The weight ratio of the vermiculite powder, dodecyl dimethyl betaine and solvent water is 10:(1.5-2.3):(50-60).

4. The acidic oil remover according to claim 1, characterized in that: The acid-activated nutshell is prepared by the following steps: The nutshell is crushed, and nutshell with a particle size of 0.5-2 mm is sieved, washed with water, and dried for standby use; Citric acid is used as an activator, and the citric acid is diluted with water to a volume concentration of 30%-50% to obtain an acid solution; The nutshell is immersed in the acid solution, and the solid-liquid ratio is 1:5-1:8 (nutshell mass / acid solution volume). The water bath is heated to 60-80℃ and stirred for 2-3 h. After the end, the nutshell is taken out and repeatedly washed with water until the filtrate is neutral. The dried nutshell is acid-activated nutshell.

5. The acidic oil remover according to claim 4, characterized in that: The nutshell is selected from one or more of walnut shell, coconut shell, and apricot shell.

6. The acidic oil remover according to claim 1, characterized in that: The organic acid is selected from a mixture of citric acid and tartaric acid, and the molar ratio of citric acid to tartaric acid is 3:1-4:

1.

7. The acidic oil remover according to claim 1, characterized in that: The surfactant is selected from a mixture of coconut diethanolamide and sorbitan fatty acid ester in a mass ratio of (1.1-1.4):

1.

8. The acidic oil remover according to claim 1, characterized in that: The inorganic acid is selected from one or more of sulfuric acid with a mass concentration of 20% and hydrochloric acid with a mass concentration of 37%.

9. The acidic oil remover according to claim 1, characterized in that: The corrosion inhibitor is selected from one or more of beta-cyclocitral, p-phenylenediformaldehyde, and coconut oil alkyl alcohol amide phosphate, and the wetting agent is selected from one or more of lauryl polyoxyethylene ether and platycodon saponin.

10. A method of preparing an acidic oil remover according to any one of claims 1 to 9, characterized in that, The following steps are included: The inorganic acid, organic acid, corrosion inhibitor, vermiculite powder, and acid-activated nutshell are sequentially added to the deionized water and fully mixed to obtain a mixed solution A, which is heated to a temperature of 50-60℃; The wetting agent and surfactant are added to the mixed solution A, and stirred for 2-3 h at a stirring rate of 150-180 r / min to obtain the acidic oil removal agent.