Acidic degreasing agent for PCB multilayer board and preparation method thereof

Abstract

The present invention relates to the technical field of printed circuit board processing, and more specifically, it relates to a preparation method of an acidic degreasing agent for PCB multilayer boards. It is composed of the following weight percentages: organic acid 8-18%, corrosion inhibitor 0.1-1.8%, foam suppressant 0.1-0.3%, surfactant 0.1-5%, hydrophobic lipophilic adsorbent 0.1-5%, and the balance is water; the hydrophobic lipophilic adsorbent is one or more of hydrophobic lipophilic modified expanded pearlite powder, hydrophobic lipophilic modified expanded graphite powder, and hydrophobic lipophilic modified expanded vermiculite powder. By using hydrophobic lipophilic modified expanded pearlite powder, hydrophobic lipophilic modified expanded graphite powder, and hydrophobic lipophilic modified expanded vermiculite powder as hydrophobic lipophilic adsorbents, the degreasing agent has a better adsorption effect on grease, residual glue, ink, etc. during the degreasing process, and the possibility of secondary pollution after degreasing a large number of PCB multilayer boards is reduced, and the probability of producing defective products is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of printed circuit board processing, and more specifically, to an acidic degreasing agent for PCB multilayer boards and a preparation method thereof. Background Art

[0002] With the rapid development of microelectronics technology, printed circuit board manufacturing is developing towards multi-layer, functional and dense directions, making printed circuit board manufacturing technology more difficult and manufacturers have increasingly higher technical requirements for electroplating processes.

[0003] PCB multilayer board belongs to the multilayer circuit board in printed circuit board, which is often used in electrical products. PCB multilayer board is composed of multiple single-sided boards and / or double-sided boards, which are then connected through positioning systems and insulating adhesive materials, and the conductive patterns are interconnected according to design requirements to form four-layer, six-layer and other printed PCB multilayer boards, also known as multilayer printed circuit boards.

[0004] The production process of PCB multilayer boards is generally: acid dipping → full-board copper electroplating → pattern transfer → acid degreasing → secondary countercurrent rinsing → micro-etching → secondary acid dipping → tin plating → secondary countercurrent rinsing → acid dipping → pattern copper plating → secondary countercurrent rinsing → nickel plating → secondary water washing → citric acid dipping → gold plating → recycling → 2-3 level pure water washing → drying.

[0005] In this process, due to the copper plating and pattern transfer of the whole board, grease impurities, ink residual glue, metal oxides, etc. will appear on the circuit surface, so acid degreasing is required. After degreasing, the grease impurities, ink residual glue, and metal oxides on the surface can be removed, and the surface of the PCB multilayer board will be neat and wettable. At the same time, it plays a certain protective role on the PCB multilayer board to avoid premature oxidation during the transmission process.

[0006] Usually the production process of PCB multilayer boards is carried out continuously. In the industrial production process, in order to improve processing efficiency, PCB multilayer boards will be degreased in large quantities, and the shorter the degreasing time, the more beneficial it is to improve production efficiency.

[0007] Usually, degreasing agents will undergo saponification reaction with grease during the degreasing process. However, as the number of PCB multilayer boards to be degreased increases, the existing degreasing agents produce more reactants during the degreasing process. Therefore, the reactants are easily suspended in the degreasing agents and then easily adsorbed on the surface of the PCB multilayer boards again, causing stains on the PCB multilayer boards and reducing the degreasing pass rate of the PCB multilayer boards.

[0008] Although the degreasing agent can be replaced or added to prevent the PCB multilayer from being stained again, the degreasing agent is replaced too frequently, and the production line needs to be stopped during each replacement, thereby reducing the production efficiency of the PCB multilayer. Further research is needed for this purpose. Summary of the invention

[0009] In order to improve the production efficiency of PCB multilayer boards, reduce the re-contamination of the surface of PCB multilayer boards after degreasing of large quantities of PCB multilayer boards, and reduce the probability of defective products, the present application provides an acidic degreasing agent for PCB multilayer boards and a preparation method thereof.

[0010] In a first aspect, the present application provides an acidic degreasing agent for PCB multilayer boards, which is composed of the following weight percentages:

[0011] Organic acid 8-18%

[0012] Corrosion inhibitor 0.1-1.8%

[0013] Antifoam 0.1-0.3%

[0014] Surfactant 0.1-5%

[0015] Hydrophobic lipophilic adsorbent 0.1-5%

[0016] The balance is water;

[0017] The hydrophobic and oleophilic adsorbent is one or more of hydrophobic and oleophilic modified expanded pearlite powder, hydrophobic and oleophilic modified expanded graphite powder, and hydrophobic and oleophilic modified expanded vermiculite powder.

[0018] In the above scheme, the hydrophobic and oleophilic modified expanded perlite powder, hydrophobic and oleophilic modified expanded graphite powder, and hydrophobic and oleophilic modified expanded vermiculite powder used in this application all have the functions of adsorbing oil, impurities, oil reactants, metal ions, hydrophobic and oleophilic, and are combined with organic acids, corrosion inhibitors, surfactants, etc., so that the obtained degreasing agent can remove grease impurities, ink residual glue, metal oxides, etc. on the surface of PCB multilayer boards, and adsorb reactants, metal ions, residual glue, residual glue and other impurities generated in the degreasing agent, reduce the generation of impurities in the degreasing agent, avoid stains on PBC multilayer boards, and improve the qualified rate of PBC multilayer boards.

[0019] Among them, the hydrophobic and oleophilic modified expanded perlite powder, the hydrophobic and oleophilic modified expanded graphite powder, and the hydrophobic and oleophilic modified expanded vermiculite powder are porous, and a hydrophobic and oleophilic coating film is formed on their surface. Therefore, in the raw material system of the degreasing agent, it is not easy to absorb water, but has a better adsorption effect on the grease in the degreasing agent. Therefore, after the generated reactants and residual glue are adsorbed, the PCB multilayer board is avoided from being contaminated again, the PCB multilayer board is made clean and moist, and the probability of producing defective products is reduced. At the same time, the grease and oxide can be removed to a greater extent, the degreasing rate can be improved, the replacement frequency of the degreasing agent can be reduced, and the processing efficiency of the PCB multilayer board can be improved to a greater extent.

[0020] In summary, the reactants, metal ions and other impurities generated in the degreasing process are adsorbed by the hydrophobic and oleophilic adsorbent composed of one or more of the hydrophobic and oleophilic modified expanded perlite powder, the hydrophobic and oleophilic modified expanded graphite powder and the hydrophobic and oleophilic modified expanded vermiculite powder, and under the action of organic acid, corrosion inhibitor, foam inhibitor, surfactant and the like, the obtained degreasing agent has a better degreasing effect, and the degreasing agent has a better adsorption effect on grease, residual glue, ink and the like in the degreasing process, thereby reducing the possibility of secondary pollution after degreasing of a large number of PCB multilayer boards and reducing the probability of producing defective products.

[0021] Preferably, the particle sizes of the hydrophobic and oleophilic modified expanded pearlite powder, the hydrophobic and oleophilic modified expanded graphite powder, and the hydrophobic and oleophilic modified expanded vermiculite powder are all 100-300 meshes.

[0022] The selection of the above particle size range is better for this application. The hydrophobic and lipophilic adsorbent within this particle size range can have a better adsorption effect on the generated reactants, metal ions, residual glue, excess glue and other impurities, reduce the stains on the PCB multilayer board, and improve the product qualification rate of PCB multilayer oil removal.

[0023] Preferably, the hydrophobic and lipophilic adsorbent is prepared from the following raw materials in parts by weight:

[0024] Expanded pearlite powder 1-10 parts

[0025] Expanded graphite powder 0-2 parts

[0026] Expanded vermiculite powder 0-3 parts

[0027] 3-15 parts of hydrophobic lipophilic modifier.

[0028] The hydrophobic and oleophilic modifier has good film-forming property, hydrophobicity and oleophilicity, and therefore, is easy to form a hydrophobic and oleophilic coating film on the surface of expanded graphite, expanded perlite powder and expanded vermiculite powder, and reduces the water absorption of the expanded graphite, expanded perlite powder and expanded vermiculite powder, so that the prepared hydrophobic and oleophilic modified expanded perlite powder, hydrophobic and oleophilic modified expanded graphite powder and hydrophobic and oleophilic modified expanded vermiculite powder have good hydrophobic and oleophilic effects, are not easy to absorb water when used in a degreasing agent, but are easy to adsorb generated reactants, metal ions, residual glue, excess glue and other impurities, so that stains are avoided on PCB multilayer boards during the degreasing process, the qualified rate of PCB multilayer boards after degreasing is improved, the frequency of replacing the degreasing agent is reduced, and the processing efficiency of PCB multilayer boards is improved.

[0029] Preferably, the hydrophobic and lipophilic modifier is prepared from the following raw materials in parts by weight:

[0030] Alkyl acrylate phosphate 0.1-0.7 parts

[0031] Dicyclopentenyl ethoxylated methacrylate 0.3-1 part

[0032] 3-(Methacryloyloxy)propyltrimethoxysilane 0.5-1.5 parts

[0033] 1.3-3.5 parts of fluorinated acrylate monomer

[0034] Initiator 0.01-0.03 parts

[0035] 10-20 parts of solvent.

[0036] Preferably, the hydrophobic lipophilic modifier is prepared by the following method:

[0037] According to weight parts, weigh fluorinated acrylate monomer, dicyclopentenyl ethoxylated methacrylate, alkyl acrylate phosphate, and initiator, mix evenly, heat to 65-75°C, react for 1-2h, then add 3-(methacryloyloxy)propyltrimethoxysilane, react for 1-3h, solvent, mix evenly to obtain a hydrophobic and lipophilic modifier.

[0038] The hydrophobic lipophilic modifier is prepared by the following method:

[0039] Weigh expanded pearlite powder, expanded graphite powder, expanded vermiculite powder and a hydrophobic and lipophilic modifier, mix them evenly, and perform reduced pressure distillation to obtain a hydrophobic and lipophilic modifier.

[0040] In the above scheme, after the copolymerization of alkyl acrylate phosphate, dicyclopentenyl ethoxylated methacrylate, 3-(methacryloyloxy)propyltrimethoxysilane, fluorinated acrylate monomer, and hydrogen-containing silicone oil into a film, it has hydrophobicity, lipophilicity, and adhesion to inorganic substances, so it is easy to adhere to the surface of expanded graphite, expanded perlite powder, and expanded vermiculite powder to form a hydrophobic, lipophilic, and acid- and alkali-resistant coating film.

[0041] Among them, the fluorinated acrylate monomer is hydrophobic and corrosion-resistant, can undergo self-polymerization, and can also react with other acrylate monomers. When cured into a film, it has better hydrophobicity, lipophilicity, and corrosion resistance.

[0042] Alkyl acrylate phosphate has good resistance to water boiling, moisture and heat, good chemical resistance and good adhesion. Dicyclopentenyl ethoxylated methacrylate has good water resistance, solvent resistance and good adhesion.

[0043] In summary, the present application adopts alkyl acrylate phosphate, dicyclopentenyl ethoxylated methacrylate, 3-(methacryloyloxy)propyltrimethoxysilane, fluorinated acrylate monomer, and hydrogenated silicone oil for compound polymerization to form a hydrophobic and lipophilic modifier having better hydrophobicity, lipophilicity, acid and alkali corrosion resistance, and film-forming properties.

[0044] Therefore, a stable coating film is formed on the surface of expanded graphite, expanded perlite powder, and expanded vermiculite powder, and its water absorption is reduced, the lipophilicity is improved, and the adsorption of reactants, metal ions, residual glue, residual glue and other impurities generated during the degreasing process is improved. Due to its acid and alkali resistance, it can play a better adsorption role in acidic degreasing agents for a long time. Therefore, in the degreasing process of large quantities of PCB multilayer boards, it can reduce the re-contamination of PCB multilayer boards and improve the qualified rate of PCB multilayer boards after degreasing.

[0045] Preferably, the fluorine-containing acrylate monomer is trifluoroethyl methacrylate and / or hexafluorobutyl methacrylate.

[0046] Trifluoroethyl methacrylate and / or hexafluorobutyl methacrylate are used in combination with alkyl acrylate phosphate, dicyclopentenyl ethoxylated methacrylate, and 3-(methacryloyloxy)propyltrimethoxysilane for compound polymerization, so that the prepared hydrophobic and lipophilic adsorbent can be used in the raw material system of the degreasing agent, thereby achieving better adsorption effect and improving the qualified rate of PCB multilayer boards after degreasing.

[0047] Preferably, the organic acid is one or more of oxalic acid, tartaric acid, malic acid and glycolic acid.

[0048] Oxalic acid, tartaric acid, malic acid, and glycolic acid can all increase hydrogen ions and have strong acidity. They can be combined with corrosion inhibitors, foam inhibitors, surfactants, and hydrophobic and lipophilic adsorbents to achieve better degreasing effects. They can also adsorb impurities generated during the degreasing process of PCB multilayer boards, reduce the probability of re-contamination of PCB multilayer boards, improve the qualified rate of PCB multilayer board degreasing, and improve the production efficiency of PCB multilayer boards.

[0049] Preferably, the corrosion inhibitor is one or more of sodium tripolyphosphate, disodium hydrogen phosphate, coconut oil alkyl alcohol amide phosphate, and benzotriazole.

[0050] Sodium tripolyphosphate and disodium hydrogen phosphate are inorganic corrosion inhibitors that can form a passivation film or a dense protective film of metal salts on the metal surface to prevent metal corrosion. Coconut oil alkyl alcohol amide phosphate and benzotriazole are organic corrosion inhibitors that can adsorb on the metal surface, cover the metal surface or active sites, and thus prevent electrochemical corrosion of the metal.

[0051] When sodium tripolyphosphate, disodium hydrogen phosphate, coconut oil alkyl alcohol amide phosphate and benzotriazole are compounded, it plays a better corrosion inhibition role, keeps the raw material system of the degreasing agent stable, and makes the degreasing agent have a better degreasing effect. In addition, long-term use or large-scale use can promote the hydrophobic and lipophilic adsorbent to stably adsorb other impurities, and obtain a higher qualified rate of PCB multilayer boards.

[0052] Preferably, the foam suppressant is selected from one or more of polyoxyethylene polyoxypropylene amine ether, dimethyl silicone oil and diisobutyl carbinol.

[0053] Polyoxyethylene polyoxypropylene amine ether, dimethyl silicone oil, and diisobutyl carbinol can reduce the foaming during the degreasing process or the degreasing process, which affects the overall degreasing effect and improve the degreasing efficiency of the degreasing agent.

[0054] Preferably, the surfactant is one or more of dodecyl dimethyl betaine, hexafluorobutanol, sodium perfluorononenyloxybenzene sulfonate, and sodium dodecylbenzene sulfonate.

[0055] Dodecyl dimethyl betaine, hexafluorobutanol, sodium perfluorononenyloxybenzene sulfonate, and sodium dodecylbenzene sulfonate all have surface activity, which improves the degreasing effect of the degreasing agent. When dodecyl dimethyl betaine, hexafluorobutanol, sodium perfluorononenyloxybenzene sulfonate, and sodium dodecylbenzene sulfonate are used in combination, they play a synergistic role, thereby making the degreasing effect of the degreasing agent better. In addition, hexafluorobutanol and sodium perfluorononenyloxybenzene sulfonate have better stability to acid solution, so the degreasing effect will not be affected during long-term degreasing. In addition, the dispersibility of the hydrophobic and lipophilic adsorbent in the degreasing agent can be improved, which is more conducive to the adsorption of impurities such as residual glue and residual glue. After a large number of PCB multilayer boards are degreased, the degreased PCB multilayer boards are not easy to produce stains, thereby reducing the defective rate of PCB multilayer boards.

[0056] In a second aspect, the present application provides a method for preparing an acidic degreasing agent for a PCB multilayer board, comprising the following steps: weighing an organic acid, a corrosion inhibitor, a foam suppressant, a surfactant, a hydrophobic and lipophilic adsorbent, and water in parts by weight and mixing them evenly to obtain a degreasing agent.

[0057] The above preparation method obtains a degreasing agent by uniformly mixing an organic acid, a corrosion inhibitor, a foam suppressant, a surfactant, a hydrophobic lipophilic adsorbent and water, and is used for degreasing PCB multilayer boards, achieving a better degreasing effect. In addition, when a large number of PCB multilayer boards are degreasing, the generation of stains on the PCB multilayer boards is reduced, thereby improving the degreasing qualified rate of the PCB multilayer boards.

[0058] In summary, this application has the following beneficial effects:

[0059] 1. The hydrophobic and oleophilic modified expanded perlite powder, hydrophobic and oleophilic modified expanded graphite powder and hydrophobic and oleophilic modified expanded vermiculite powder are porous, and a hydrophobic and oleophilic coating film is formed on their surface. Therefore, in the raw material system of the degreasing agent, it is not easy to absorb water, but has a better adsorption effect on the impurities in the degreasing agent. Therefore, after the generated reactants and residual glue are adsorbed, the PCB multilayer board is prevented from being contaminated again, making the PCB multilayer board clean and moist, reducing the probability of producing defective products, and at the same time, it can further limit the removal of grease and oxides, improve the degreasing rate, reduce the replacement frequency of the degreasing agent, and maximize the processing efficiency of the PCB multilayer board.

[0060] 2. After copolymerization of alkyl acrylate phosphate, dicyclopentenyl ethoxylated methacrylate, 3-(methacryloyloxy)propyl trimethoxysilane, fluorinated acrylate monomer, and hydrogenated silicone oil into a film, the film has hydrophobicity, lipophilicity, and adhesion to inorganic substances, so it is easy to adhere to the surface of expanded graphite, expanded pearlite powder, and expanded vermiculite powder to form a coating film with hydrophobicity, lipophilicity, and acid and alkali resistance. And then reduce its water absorption, improve lipophilicity, and then improve the adsorption of the generated reactants, metal ions, residual glue, excess glue, and other impurities in the degreasing process. Because of acid and alkali resistance, it can be used in acidic degreasing agents for a long time, and play a better adsorption effect. Therefore, in the degreasing process of large quantities of PCB multilayer boards, it can reduce the re-contamination of PCB multilayer boards and improve the qualified rate of PCB multilayer boards after degreasing. DETAILED DESCRIPTION

[0061] The present application is further described in detail below with reference to the embodiments.

[0062] The sources or parameters of some raw materials;

[0063] Table 1 Sources or parameters of some raw materials

[0064]

[0065] Example

[0066] Example 1

[0067] An acidic degreasing agent for a PCB multilayer board and a preparation method thereof, comprising the following steps: weighing 8kg of an organic acid, 0.1kg of a corrosion inhibitor, 0.3kg of a foam suppressant, 5kg of a surfactant, 5kg of a hydrophobic lipophilic adsorbent, and 81.6kg of water into a stirring device, stirring at a rotation speed of 100r / mi for 30min to fully mix the raw materials and obtain a degreasing agent.

[0068] The hydrophobic and oleophilic adsorbent is hydrophobic and oleophilic modified expanded perlite powder;

[0069] The hydrophobic and oleophilic modified expanded pearlite powder is prepared by the following method:

[0070] Weigh 5 kg of expanded perlite powder, 5 kg of 50% ethanol solution, and 0.5 kg of γ-(methacryloyloxy)propyltrimethoxysilane and put them into a stirring device. Stir for 30 minutes at a speed of 100 r / min, filter, and dry at 80°C for 2 hours to obtain hydrophobic and lipophilic modified expanded perlite powder.

[0071] The organic acid is composed of oxalic acid and tartaric acid in a weight ratio of 1.3:0.7; the corrosion inhibitor is sodium tripolyphosphate, the foam suppressant is polyoxyethylene polyoxypropylene amine ether; and the surfactant is dodecyl dimethyl betaine.

[0072] Example 2-3

[0073] The difference between Example 2-3 and Example 1 is that the amount of raw materials used is different, as shown in Table 2;

[0074] Amount of raw materials used in Examples 1-3 (kg)

[0075]

[0076] Example 4

[0077] The difference between Example 4 and Example 2 is that the hydrophobic and lipophilic adsorbent is prepared by the following method:

[0078] Weigh 1.3 kg of fluorinated acrylate monomer, 1 kg of dicyclopentenyl ethoxylated methacrylate, 0.1 kg of alkyl acrylate phosphate, and 0.01 kg of initiator (benzoyl peroxide) into a reaction kettle and mix well, heat to 65 ° C, react for 1 hour, then add 0.5 kg of 3-(methacryloyloxy)propyltrimethoxysilane, react for 3 hours, add 10 kg of solvent, mix well, and obtain a hydrophobic and lipophilic modifier;

[0079] Weigh 0.1 kg of expanded pearlite powder and 3 kg of hydrophobic lipophilic modifier, mix them evenly, and distill them under reduced pressure at a temperature of 120° C. The vacuum gauge shows -0.1 MPa. Remove the solvent to obtain the hydrophobic lipophilic modifier.

[0080] The solvent was ethyl acetate.

[0081] The fluorinated acrylate monomer is trifluoroethyl methacrylate.

[0082] Embodiment 5-6

[0083] The difference between Example 5-6 and Example 4 is that the amount of raw materials used for the hydrophobic and lipophilic adsorbents is different: the amount of raw materials used in Examples 4-6 (kg)

[0084]

[0085] Example 10

[0086] The difference between Example 10 and Example 9 is that the fluorine-containing acrylate monomer is hexafluorobutyl methacrylate.

[0087] Embodiment 11

[0088] The difference between Example 11 and Example 9 is that the fluorine-containing acrylate monomer consists of 1.3 kg of trifluoroethyl methacrylate and 1.2 kg of hexafluorobutyl methacrylate.

[0089] Example 12

[0090] The difference between Example 12 and Example 4 is that the alkyl acrylate phosphate is replaced by dicyclopentenyl ethoxylated methacrylate in equal amounts.

[0091] Embodiment 13

[0092] The difference between Example 13 and Example 4 is that 3-(methacryloyloxy)propyltrimethoxysilane is replaced by dicyclopentenyl ethoxylated methacrylate in an equal amount.

[0093] Embodiment 14

[0094] The difference between Example 14 and Example 4 is that: alkyl acrylate phosphate,

[0095] Dicyclopentenyl ethoxylated methacrylate and 3-(methacryloyloxy)propyltrimethoxysilane were replaced with fluorinated acrylic monomers in equal amounts.

[0096] Embodiment 15

[0097] The difference between Example 15 and Example 11 is that the surfactant consists of 1 kg of dodecyl dimethyl betaine, 0.2 kg of hexafluorobutanol, 0.8 kg of sodium perfluorononenyloxybenzene sulfonate, and 1 kg of sodium dodecylbenzene sulfonate.

[0098] Example 16

[0099] The difference between Example 16 and Example 15 is that the corrosion inhibitor consists of 0.1 kg sodium tripolyphosphate, 0.1 kg disodium hydrogen phosphate, 0.5 kg coconut oil alkyl alcohol amide phosphate, and 0.2 kg benzotriazole.

[0100] Comparative Example

[0101] Comparative Example 1

[0102] The difference between Comparative Example 1 and Example 1 is that the hydrophobic and lipophilic adsorbents are replaced by surfactants in equal amounts.

[0103] Comparative Example 2

[0104] The difference between Comparative Example 2 and Example 1 is that the hydrophobic and lipophilic adsorbent is expanded perlite.

[0105] Performance testing

[0106] Detection method / test method

[0107] The degreasing agents obtained from Examples 1-16 and Comparative Examples 1-2 were subjected to the following tests.

[0108] Large-scale degreasing experiment, check whether the surface is clean after degreasing:

[0109] The PCB multilayer board is a 10-layer PCB multilayer board, and the manufacturer is preferably Shenzhen Dingji Electronics Co., Ltd., with a board thickness of 1.6MM; batch number DJ5255; package PCBA; surface treatment, immersion gold; solder mask color; green oil; substrate FR-4T170; copper thickness 1OZ; line width and line spacing 3 / 3Mil;

[0110] Experimental process: 200 PCB multilayer boards were sprayed with 50g / m 2 The green oil is sent to the degreasing tank for degreasing, the degreasing time is 2 minutes, the degreasing temperature is 30°C, and then it is neutralized in the neutralizing liquid, the neutralizing liquid is a 5% sodium carbonate solution by mass, the neutralization time is 1 minute, and the neutralization temperature is 25°C. Then it is sent to the clean water tank for cleaning, the cleaning time is 30 seconds, and then it is sent to a 100°C oven for drying for 10 minutes to obtain a degreasing PCB multilayer board. After repeating the above experiments 20 times, 30 times, and 50 times respectively, observe whether there are residues, attachments, water stains, etc. on the surface through a 50x magnifying glass. If there is no above phenomenon, it is recorded as qualified, and the qualified rate is calculated;

[0111] Table 2 Experimental data of Examples 1-16 and Comparative Examples 1-2

[0112]

[0113] It can be seen from Example 1 and Comparative Examples 1-2 and Table 2 that after 30 batch degreasings, the qualified rate of Example 1 is higher than the qualified rate of Comparative Examples 1-2, indicating that the degreasing agent composed of the raw materials and proportions of the present application has a better degreasing effect, reduces the re-adhesion of impurities in the degreasing process of large-scale PCB multilayer boards, improves the qualified rate of PCB multilayer board degreasing, and thus improves the processing efficiency of PCB multilayer boards.

[0114] Comparing Example 2, Example 12-14 and Example 4 and combining Table 2, it can be seen that after 30 batch degreasings, the qualified rates of Example 2 and Example 12-144 are lower than the qualified rate of the embodiment, indicating that the hydrophobic oleophilic modifier prepared by compounding fluorinated acrylate monomer, dicyclopentenyl ethoxylated methacrylate and alkyl acrylate phosphate has a better hydrophobic oleophilic effect, and then the hydrophobic oleophilic adsorbent prepared by expanding graphite has better hydrophobicity and adsorption, and is used in the degreasing agent to reduce impurities, water stains, etc. adhered to the surface of the PCB multilayer board after batch degreasing, thereby improving the qualified rate of degreasing.

[0115] Comparing Example 5 and Example 9 and combining Table 2, it can be seen that after 30 batch degreasings, the qualified rate of Example 9 is higher than that of Example 5, indicating that the use of expanded perlite powder, expanded graphite, and expanded vermiculite powder compounding plays a synergistic role, and the hydrophobic lipophilic modifier prepared in the present application is combined to make the obtained hydrophobic lipophilic adsorbent have better hydrophobicity and adsorption, and is used in degreasing agents to reduce impurities, water stains, etc. adhered to the surface of PCB multilayer boards after batch degreasing, thereby improving the qualified rate of degreasing.

[0116] Comparing Example 9 and Example 11 and combining with Table 2, it can be seen that after 30 batch degreasings, the qualified rate of Example 11 is higher than that of Example 9, indicating that the use of trifluoroethyl methacrylate and hexafluorobutyl methacrylate compounding plays a synergistic role, and cooperates with dicyclopentenyl ethoxylated methacrylate and alkyl acrylate phosphate, so that the prepared hydrophobic lipophilic modifier has a better modification effect on expanded perlite powder, expanded graphite, and expanded vermiculite powder, so that the obtained hydrophobic lipophilic adsorbent is used in the degreasing agent, which reduces the impurities, water stains, etc. adhered to the surface of the PCB multilayer board after batch degreasing, and improves the qualified rate of degreasing.

[0117] By comparing Example 11 and Example 15 and combining with Table 2, it can be seen that after 30 batch oil removals, the qualified rate of Example 15 is higher than that of Example 11, indicating that the surfactant obtained by using dodecyl dimethyl betaine, hexafluorobutanol, sodium perfluorononenyloxybenzene sulfonate, and sodium dodecylbenzene sulfonate, and then combining with the deoiling agent raw material system of the present application, has a better oil removal effect and improves the oil removal qualified rate.

[0118] By comparing Example 11 and Example 15 and combining with Table 2, it can be seen that after 30 batch degreasings, the qualified rate of Example 15 is higher than that of Example 11, indicating that the use of sodium tripolyphosphate, disodium hydrogen phosphate, coconut oil alkyl alcohol amide phosphate, and benzotriazole for compounding, and then combining with the degreasing agent raw material system of the present application, the degreasing agent has a better degreasing effect and improves the qualified rate of the product after degreasing.

[0119] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this document, a person skilled in the art may make modifications to the present embodiment as needed without any creative contribution. However, as long as the modifications are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. An acidic degreasing agent for PCB multilayer boards, characterized in that: Composed of the following percentages by weight: Organic acid 8-18% Corrosion inhibitor 0.1-1.8% Antifoam 0.1-0.3% Surfactant 0.1-5% Hydrophobic and lipophilic adsorbent 0.1-5% The balance is water; The hydrophobic and oleophilic adsorbent is one or more of hydrophobic and oleophilic modified expanded pearlite powder, hydrophobic and oleophilic modified expanded graphite powder, and hydrophobic and oleophilic modified expanded vermiculite powder.

2. The acidic degreasing agent for PCB multilayer boards according to claim 1, characterized in that: The particle sizes of the hydrophobic and oleophilic modified expanded pearlite powder, the hydrophobic and oleophilic modified expanded graphite powder and the hydrophobic and oleophilic modified expanded vermiculite powder are all 100-300 meshes.

3. The acidic degreasing agent for PCB multilayer boards according to claim 1, characterized in that: The hydrophobic and lipophilic adsorbent is prepared from the following raw materials in parts by weight: Expanded pearlite powder 1-10 parts Expanded graphite powder 0-2 parts Expanded vermiculite powder 0-3 parts 3-15 parts of hydrophobic lipophilic modifier.

4. The acidic degreasing agent for PCB multilayer boards according to claim 3, characterized in that: The hydrophobic and lipophilic modifier is prepared from the following raw materials in parts by weight: Alkyl acrylate phosphate 0.1-0.7 parts Dicyclopentenyl ethoxylated methacrylate 0.3-1 part 3-(Methacryloyloxy)propyltrimethoxysilane 0.5-1.5 parts 1.3-3.5 parts of fluorinated acrylate monomer Initiator 0.01-0.03 parts 10-20 parts of solvent.

5. The acidic degreasing agent for PCB multilayer boards according to claim 4, characterized in that: The fluorine-containing acrylic ester monomer is trifluoroethyl methacrylate and / or hexafluorobutyl methacrylate.

6. The acidic degreasing agent for PCB multilayer boards according to claim 1, characterized in that: The organic acid is one or more of oxalic acid, tartaric acid, malic acid and glycolic acid.

7. The acidic degreasing agent for PCB multilayer boards according to claim 1, characterized in that: The corrosion inhibitor is one or more of sodium tripolyphosphate, disodium hydrogen phosphate, coconut oil alkyl alcohol amide phosphate, and benzotriazole.

8. The acidic degreasing agent for PCB multilayer boards according to claim 1, characterized in that: The foam suppressant is one or more of polyoxyethylene polyoxypropylene amine ether, dimethyl silicone oil and diisobutyl carbinol.

9. The acidic degreasing agent for PCB multilayer boards according to claim 1, characterized in that: The surfactant is one or more of dodecyl dimethyl betaine, hexafluorobutanol, sodium perfluorononenyloxybenzene sulfonate, and sodium dodecylbenzene sulfonate.

10. A method for preparing an acidic degreasing agent for PCB multilayer boards according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: weighing organic acid, corrosion inhibitor, foam inhibitor, surfactant, hydrophobic lipophilic adsorbent and water according to weight parts, mixing them evenly, and obtaining degreasing agent.

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