A circuit board inkjet printing ink stripping agent, and a preparation method and application thereof

Abstract

The application discloses a circuit board inkjet printing ink stripping agent and a preparation method and application thereof, and relates to the technical field of printed circuit board production. The circuit board inkjet printing ink stripping agent is composed of the following components in mass concentration: a stripping agent 1.5-7.0%, a cosolvent 1.0-5.0%, an accelerator 1.0-3.0%, an emulsifier 1.0-5.5%, a protective agent 0.2-2.7%, and the balance being water. The application provides a circuit board inkjet printing ink stripping agent and a preparation method and application thereof. The ink stripping agent realizes effective stripping of inkjet printing ink through the synergistic effect of the stripping agent, the cosolvent, the accelerator, the emulsifier and the protective agent, does not damage the copper on the substrate and the circuit, and reduces the probability of scrapping of the circuit board.

Description

Technical Field

[0001] This invention relates to the field of printed circuit board manufacturing technology, and in particular to a stripping agent for inkjet printing of circuit boards, its preparation method and application. Background Technology

[0002] In recent years, with the increasing demand for high-end products, the PCB industry is facing new reforms and development. The need to gradually eliminate outdated production capacity, upgrade PCB manufacturing processes, and reduce pollutant emissions during production is imperative. The PCB solder mask production process involves numerous steps: board entry → grinding → screen printing solder mask → pre-baking → alignment and exposure → development → QC inspection → character printing → post-baking → QC inspection. This complex process can lead to poor ink quality due to various factors. Inkjet printing technology, with its comprehensive digital manufacturing process, has gained widespread recognition in the PCB industry. It offers advantages such as high quality, low cost, and environmental friendliness, requiring only three processes: pre-treatment → inkjet printing → post-curing. This significantly reduces production line area, lowers equipment investment by over 50%, and greatly saves labor costs. This technology is gradually replacing traditional screen printing solder mask technology.

[0003] Inkjet printing has very strict requirements on ink type, equipment printing configuration and parameters, and pretreatment process. Even slight mismatches in any aspect can easily lead to problems such as ink diffusion, obvious deviations in printed lines, and ink shedding after baking, resulting in defective products and scrap, thereby increasing the production costs of enterprises. Therefore, an inkjet printing ink stripper is needed to remove ink from scrapped boards, enabling the reuse of defective products and effectively reducing the production costs of enterprises.

[0004] Currently, most PCB manufacturers use a high-temperature sodium hydroxide immersion method to remove ink, which involves immersing the PCB in a 90°C sodium hydroxide solution for 2-3 hours. This method can only remove regular inks and is very ineffective at removing inkjet printing inks. Furthermore, it can damage the PCB substrate and copper surface, rendering the PCB completely unusable.

[0005] Chinese patent CN 114980550 A discloses a circuit board ink stripping agent and a method for removing circuit board ink. Although this ink stripping agent has the advantages of high stripping efficiency and protection of copper from corrosion, it is only effective for removing conventional inks. Because the composition of inkjet printing inks differs significantly from that of conventional inks, these conventional ink stripping methods are unlikely to remove inkjet inks effectively, and may even damage the circuit board, causing open circuits, short circuits, and other defects. The substrate may also develop white spots and visible ripples, leading to the scrapping of the circuit board. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a circuit board inkjet printing ink stripper, its preparation method, and its application. This ink stripper contains effective components such as a stripper, a co-solvent, an accelerator, an emulsifier, and a protective agent. Furthermore, this circuit board inkjet printing ink stripping method replaces the traditional high-temperature, strong-alkali ink stripping method, exhibiting excellent ink stripping performance. Simultaneously, the stripping process operates at a lower temperature, and the effective components do not damage the substrate or the copper on the circuitry, significantly reducing the probability of circuit board scrap and demonstrating promising application prospects.

[0007] Specifically, the following technical solutions are included:

[0008] In a first aspect, a circuit board inkjet printing ink stripper is provided, comprising the following components by mass concentration:

[0009] The composition of the product is as follows: stripping agent 1.5-7.0%, cosolvent 1.0-5.0%, accelerator 1.0-3.0%, emulsifier 1.0-5.5%, protectant 0.2-2.7%, and the balance is water.

[0010] The stripping agent is selected from one or more of 4-nitrophenyl trifluoroacetate (CAS No.: 658-78-6), 2-methylcyclohexyl acetate (CAS No.: 5726-19-2), and ethylene glycol phenyl ether acetate (CAS No.: 6192-44-5);

[0011] The co-solvent is selected from one or more of N-benzyloxycarbonyl-L-proline (CAS No.: 1148-11-4), trans-4-hydroxy-D-proline (CAS No.: 3398-22-9), and trans-4-amino-L-proline (CAS No.: 16257-88-8);

[0012] The accelerator is selected from one or more of 7-amino-α-tetrahydronaphthone (CAS No.: 22009-40-1), 8-amino-1-tetrahydronaphthone (CAS No.: 210346-49-9), and 6-amino-1-tetrahydronaphthone (CAS No.: 3470-53-9);

[0013] The emulsifier is selected from one or more of N-(tert-butoxycarbonyl)glycine ethyl ester (CAS No.: 14719-37-0), N-tert-butoxycarbonyl-D-threonine methyl ester (CAS No.: 96099-84-2), and N-(tert-butoxycarbonyl)-D-serine β-lactone (CAS No.: 126330-77-6);

[0014] The protective agent is selected from one or more of 2-nitroiminoimidazoline (CAS No.: 5465-96-3), 1,3-dimethyl-2-(2-thienyl)imidazoline (CAS No.: 104208-13-1), and 2,2-difluoro-1,3-dimethyl-imidazoline (CAS No.: 220405-40-3).

[0015] Furthermore, the mass ratio of the co-solvent to the stripping agent is 1:(0.5-2).

[0016] Furthermore, the mass concentration of the stripping agent is 2.0-6.0%.

[0017] Furthermore, the mass concentration of the co-solvent is 1.5-4.0%.

[0018] Furthermore, the mass concentration of the accelerator is 1.5-3.0%.

[0019] Furthermore, the mass concentration of the emulsifier is 1.5-5.5%.

[0020] Furthermore, the mass concentration of the protective agent is 0.5-2.5%.

[0021] Furthermore, the circuit board inkjet printing ink stripper is composed of the following components by mass concentration:

[0022] The composition is as follows: stripping agent 2.0-6.0%, cosolvent 1.5-4.0%, accelerator 1.5-3.0%, emulsifier 1.5-5.5%, protectant 0.5-2.5%, and the balance is water.

[0023] Secondly, a method for preparing the ink stripper for inkjet printing of circuit boards as described in the first aspect is provided, comprising the following steps: weighing the stripper, cosolvent, accelerator, emulsifier, protectant and water in sequence, and stirring and mixing them at room temperature of 25°C for 15-20 minutes to obtain the ink stripper for inkjet printing of circuit boards.

[0024] Thirdly, a method for removing ink from printed circuit boards is provided, comprising the following steps: S1. First water wash; S2. Alkali wash; S3. Second water wash; S4. Removal; S5. Third water wash; S6. Drying; wherein, step S4 involves using the ink removal agent for printed circuit boards as described in the first aspect to remove ink from the printed circuit board.

[0025] The beneficial effects of this invention are as follows:

[0026] This invention provides an ink stripper for inkjet printing on circuit boards, its preparation method, and its application. In this ink stripper, the stripper is the most important component for its stripping effect. It primarily interacts with the ink through its functional groups, weakening the mutual attraction between resins, resulting in a loose structure and easy dispersion. The co-solvent is an auxiliary component of the ink stripper. It acts on the ink surface and continuously penetrates into the interior, generating osmotic pressure and accelerating the penetration of the stripper into the ink, promoting ink dissolution. The accelerator component promotes ink swelling, accelerating the stripping speed. The emulsifier reduces its surface tension, accelerates the reaction speed between the ink and the chemical, and improves stripping efficiency. The protective agent protects the circuit board from corrosion during ink stripping, maintaining the integrity of the circuitry. This invention, through the synergistic effect of the stripper, co-solvent, accelerator, emulsifier, and protective agent, effectively removes inkjet printing ink without damaging the substrate and copper on the circuitry, reducing the probability of circuit board failure. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a diagram of the printed circuit board before it is treated by the ink stripping method for printed circuit board according to Embodiment 1 of the present invention.

[0029] Figure 2 This is a diagram showing the effect of the printed circuit board after being treated by the ink stripping method for printed circuit boards according to Embodiment 1 of the present invention. Detailed Implementation

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0032] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0033] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0034] To better understand the technical content of the present invention, the technical solution of the present invention will be further introduced and explained below with reference to specific embodiments.

[0035] In this specification, "%" refers to mass concentration or mass fraction, unless otherwise specified.

[0036] Preparation method of ink stripper for inkjet printing of circuit boards:

[0037] Weigh out the stripping agent, cosolvent, accelerator, emulsifier, protectant and water in sequence, and stir and mix them at room temperature of 25℃ for 15-20 minutes to obtain the ink stripping agent for circuit board inkjet printing.

[0038] Performance testing

[0039] The performance of the ink stripper for inkjet printing of the circuit board of the present invention is mainly reflected in three aspects. The first is the degree of ink removal, which is determined by visually observing whether there is ink residue on the circuit board after treatment by the ink stripper method. The second is the integrity of the substrate, which is determined by whether the removal of ink affects the substrate, and whether there are white spots or ripples on the substrate surface of the circuit board after treatment by the ink stripper method. The third is the integrity of the copper surface, which is determined by whether the removal of ink affects the copper surface, and whether the copper surface of the circuit board after treatment by the ink stripper method is corroded.

[0040] A method for removing ink from printed circuit boards:

[0041] S1. First water wash; S2. Alkali wash; S3. Second water wash; S4. Stripping; S5. Third water wash; S6. Drying; wherein, step S4 is to use the aforementioned circuit board inkjet printing ink stripper to strip the ink from the printed circuit board.

[0042] Specifically, the first water washing step S1 involves washing the printed circuit board (PCB) requiring ink stripping with tap water to remove surface impurities. The process parameters for the first water washing step are: spray method, water washing tank length 2.0m, tank liquid temperature 25±5 ℃, water washing tank length 2.0 m; linear speed 3.0±0.5 m / min, pressure 1.5±0.5 kg / cm 2 (The specific process parameters for the first water washing process used in the embodiments and comparative examples of this invention are: bath temperature 25℃, linear velocity 3.0m / min, and pressure 1.5 kg / cm².) 2 );

[0043] The alkaline washing process in step S2 involves immersing the printed circuit board that has undergone the first water washing process in S1 in an alkaline solution. The process parameters for the alkaline washing process are as follows: the solution in the alkaline washing tank is prepared by immersion, with 5% sodium hydroxide and the remainder being tap water; the pre-immersion time is 10±2 min, and the alkaline washing temperature is 50±5℃. (The specific process parameters for the alkaline washing process used in the embodiments and comparative examples of this invention are a pre-immersion time of 10 min and an alkaline washing temperature of 50℃).

[0044] The second water washing process in S3 involves rinsing the printed circuit board that has undergone the alkaline washing process in S2 with tap water. The process parameters for the second water washing process are as follows: spray method, tank length 2.0m, tank temperature 25±5℃, water washing tank length 2.0m; linear velocity 3.0±0.5 m / min, pressure 1.5±0.5 kg / cm². 2 (The specific process parameters for the second water washing process used in the embodiments and comparative examples of this invention are: bath temperature 25 ℃, linear velocity 3.0 m / min, and pressure 1.5 kg / cm².) 2 );

[0045] The S4 stripping process involves using the ink stripping agent for inkjet printing of the printed circuit board according to the embodiments or comparative examples of the present invention to remove ink from the printed circuit board after the second water washing process in S3. The process parameters for the stripping process are: immersion method, immersion time 10±2 min, and stripping temperature 50±5℃; (the specific process parameters for the stripping process used in the embodiments and comparative examples of the present invention are immersion time 10 min and stripping temperature 50℃).

[0046] The third water washing process in S5 involves washing the printed circuit board that has undergone the stripping process in S4 with tap water. The process parameters for the third water washing process are as follows: spray method, tank length 2.0m, tank temperature 25±5℃, water washing tank length 2.0m; linear speed 3.0±0.5 m / min, pressure 1.5±0.5 kg / cm². 2(The specific process parameters for the third water washing process used in the embodiments and comparative examples of this invention are: bath temperature 25℃, linear velocity 3.0m / min, and pressure 1.5 kg / cm².) 2 );

[0047] The drying process in S6 involves drying the printed circuit board that has undergone the third water washing process in S5 with DI water. The process parameters for the drying section are: drying temperature 75±5℃ and drying time 5±1 min. (The specific process parameters for the drying process used in the embodiments and comparative examples of this invention are drying temperature 75℃ and drying time 5 min).

[0048] Example 1

[0049] An ink stripper for inkjet printing of circuit boards, comprising the following components by mass concentration:

[0050] The stripping agent is 3.0%, specifically 4-nitrophenyl trifluoroacetate;

[0051] The cosolvent is 2.0%, specifically N-benzyloxycarbonyl-L-proline;

[0052] Accelerator 2.5%, specifically 7-amino-α-tetrahydronaphthone;

[0053] Emulsifier 2.5%, specifically N-(tert-butyloxycarbonyl)glycine ethyl ester;

[0054] Protective agent 1.5%, specifically 2-nitroiminoimidazolidine;

[0055] The remainder is water.

[0056] The preparation method of ink stripper for inkjet printing of circuit boards includes the following steps: weighing stripper, cosolvent, accelerator, emulsifier, protectant and water in sequence, stirring and mixing at room temperature of 25°C for 15 minutes to obtain ink stripper for inkjet printing of circuit boards, and sealing and storing the obtained ink stripper for inkjet printing of circuit boards in a dry place at room temperature (25°C) for later use.

[0057] Example 2

[0058] An ink stripper for inkjet printing of circuit boards, comprising the following components by mass concentration:

[0059] The stripping agent is 3.0%, specifically 2-methylcyclohexyl acetate;

[0060] The cosolvent is 2.0%, specifically trans-4-hydroxy-D-proline;

[0061] Accelerator 2.5%, specifically 8-amino-1-tetrahydronaphthone;

[0062] Emulsifier 2.5%, specifically N-tert-butoxycarbonyl-D-threonine methyl ester;

[0063] The protective agent is 1.5%, specifically 1,3-dimethyl-2-(2-thienyl)imidazolidine;

[0064] The remainder is water.

[0065] Example 3

[0066] An ink stripper for inkjet printing of circuit boards, comprising the following components by mass concentration:

[0067] The stripping agent is 3.0%, specifically ethylene glycol phenyl ether acetate;

[0068] The cosolvent is 2.0%, specifically trans-4-amino-L-proline;

[0069] Accelerator 2.5%, specifically 6-amino-1-tetrahydronaphthone;

[0070] The emulsifier is 2.5%, specifically N-(tert-butoxycarbonyl)-D-serine β-lactone;

[0071] The protective agent is 1.5%, specifically 2,2-difluoro-1,3-dimethyl-imidazolidine;

[0072] The remainder is water.

[0073] Example 4

[0074] An ink stripper for inkjet printing of circuit boards, comprising the following components by mass concentration:

[0075] The stripping agent is 2.0%, specifically 4-nitrophenyl trifluoroacetate;

[0076] The cosolvent is 1.5%, specifically trans-4-amino-L-proline;

[0077] Accelerator 1.5%, specifically 8-amino-1-tetrahydronaphthone;

[0078] The emulsifier is 1.5%, specifically N-(tert-butoxycarbonyl)-D-serine β-lactone;

[0079] The protective agent is 0.5%, specifically 2-nitroiminoimidazolidine;

[0080] The remainder is water.

[0081] Example 5

[0082] An ink stripper for inkjet printing of circuit boards, comprising the following components by mass concentration:

[0083] The stripping agent is 6.0%, specifically ethylene glycol phenyl ether acetate;

[0084] The cosolvent is 4.0%, specifically trans-4-hydroxy-D-proline;

[0085] Accelerator 3.0%, specifically 7-amino-α-tetrahydronaphthone;

[0086] The emulsifier is 5.5%, specifically N-(tert-butyloxycarbonyl)glycine ethyl ester;

[0087] The protective agent is 2.5%, specifically 2,2-difluoro-1,3-dimethyl-imidazolidine;

[0088] The remainder is water.

[0089] Comparative Example 1

[0090] The only difference between Comparative Example 1 and Example 1 is that the ink stripper for circuit board inkjet printing does not contain a stripper.

[0091] Comparative Example 2

[0092] The only difference between Comparative Example 2 and Example 1 is that the ink stripper for circuit board inkjet printing does not contain a co-solvent.

[0093] Comparative Example 3

[0094] The only difference between Comparative Example 3 and Example 1 is that the ink stripper for circuit board inkjet printing does not contain an accelerator.

[0095] Comparative Example 4

[0096] The only difference between Comparative Example 4 and Example 1 is that the ink stripper for circuit board inkjet printing does not contain emulsifiers.

[0097] Comparative Example 5

[0098] The only difference between Comparative Example 5 and Example 1 is that the ink stripper for circuit board inkjet printing does not contain a protective agent.

[0099] Comparative Example 6

[0100] The only difference between Comparative Example 6 and Example 1 is that the ink stripper for circuit board inkjet printing does not contain cosolvents and accelerators.

[0101] Comparative Example 7

[0102] The only difference between Comparative Example 7 and Example 1 is that the ink stripper for circuit board inkjet printing does not contain cosolvents and emulsifiers.

[0103] Comparative Example 8

[0104] The only difference between Comparative Example 8 and Example 1 is that the ink stripper for circuit board inkjet printing does not contain accelerators and emulsifiers.

[0105] Comparative Example 9

[0106] The only difference between Comparative Example 9 and Example 1 is that the stripper concentration in the inkjet printing ink stripper for circuit boards is 0.5%.

[0107] Comparative Example 10

[0108] The only difference between Comparative Example 10 and Example 1 is that the cosolvent concentration in the ink stripper for circuit board inkjet printing is 0.5%.

[0109] Comparative Example 11

[0110] The only difference between Comparative Example 11 and Example 1 is that the accelerator concentration in the ink stripper for circuit board inkjet printing is 0.5%.

[0111] Comparative Example 12

[0112] The only difference between Comparative Example 12 and Example 1 is that the emulsifier concentration in the ink stripper for circuit board inkjet printing is 0.5%.

[0113] Comparative Example 13

[0114] The only difference between Comparative Example 13 and Example 1 is that the concentration of the protective agent in the ink stripper for circuit board inkjet printing is 0.1%.

[0115] Comparative Example 14

[0116] The difference between Comparative Example 14 and Example 1 is that the mass ratio of cosolvent to stripper in the inkjet printing ink remover for circuit boards is 1:4.

[0117] Comparative Example 15

[0118] The only difference between Comparative Example 15 and Example 1 is that the stripping agent was replaced with an equal mass concentration of ethylene glycol butyl ether acetate (CAS No.: 112-07-2).

[0119] Comparative Example 16

[0120] The only difference between Comparative Example 16 and Example 1 is that the cosolvent was replaced with an equal mass concentration of proline-proline hydrochloride (CAS No.: 76932-06-4).

[0121] Comparative Example 17

[0122] The only difference between Comparative Example 17 and Example 1 is that the accelerator was replaced with an equal mass concentration of 1-tetrahydronaphthone (CAS No.: 529-34-0).

[0123] Comparative Example 18

[0124] The only difference between Comparative Example 18 and Example 1 is that the emulsifier was replaced with an equal mass concentration of N-(tert-butyloxycarbonyl)phosphatidylamino acid diethyl ester (CAS No.: 85232-02-6).

[0125] Comparative Example 19

[0126] The only difference between Comparative Example 19 and Example 1 is that the protective agent was replaced with an equal mass concentration of benzotriazole (CAS No.: 95-14-7).

[0127] Comparative Example 20

[0128] Comparative Example 20 differs from Example 1 in that it uses prior art (Chinese Patent CN202210868026.2). Specifically, Comparative Example 20, by mass fraction, consists of the following components:

[0129] N,N-Diethyl-4-aminobenzenesulfonamide 3.0%;

[0130] 3-O-cyclobutane carboxylic acid 3.0%;

[0131] 1-Methylindazole-3-carboxylic acid 2.0%;

[0132] Thiophene-2-carboxyaldehyde diethyl acetal 2.0%;

[0133] The remainder is water.

[0134] The preparation methods of the ink stripper for circuit board inkjet printing in Examples 2-5 and Comparative Examples 1-20 are the same as those in Example 1.

[0135] The ink stripper for circuit board inkjet printing in Examples 1-5 were subjected to performance testing. The test results are shown in Table 1 below.

[0136] Table 1. Test results of ink stripper performance for inkjet printing of circuit boards in Examples 1-5

[0137]

[0138] Figure 1 This is a diagram of the printed circuit board before it is treated by the ink stripping method for printed circuit board according to Embodiment 1 of the present invention. Figure 2 This is an image showing the effect of a printed circuit board after being treated by the circuit board ink stripping method of Embodiment 1 of the present invention. Figures 1-2 As shown in the test results in Table 1, the ink stripper for inkjet printing of the present invention can efficiently remove inkjet printing ink from the circuit board. After removing the ink, the circuit board substrate has no white spots or ripples, and the copper surface has no corrosion. The circuit board remains intact, which can avoid scrap losses caused by damage to the circuit board.

[0139] The performance of the ink stripper for circuit board inkjet printing, compared with examples 1-8, was tested. The test results are shown in Table 2 below.

[0140] Table 2. Test results of ink stripper performance for inkjet printing of circuit boards in Comparative Examples 1-8

[0141]

[0142] As shown in Table 2, the difference between Comparative Examples 1-5 and Example 1 is that the ink stripper for circuit board inkjet printing lacks a single component of the stripper, co-solvent, accelerator, emulsifier, or protectant, respectively. The test results indicate that the stripper is the main active ingredient in the inkjet printing ink stripper of this invention; the absence of the stripper component leads to ink that cannot be removed. The co-solvent, accelerator, and emulsifier play an auxiliary role in ink removal; the absence of any one of these components results in a small amount of ink residue after removal. The protectant protects the circuit board from corrosion; the absence of the protectant results in white spots, exposed ripples, and severe copper corrosion on most substrates. Comparative Examples 6-7 differ from Example 1 in that they lack multiple components in the inkjet printing ink stripper for circuit boards, and their test results are worse than those of Comparative Examples 2-4. Therefore, this invention achieves the technical effect of efficiently removing inkjet printing from circuit boards through the synergistic effect of multiple components.

[0143] The performance of the ink stripper for circuit board inkjet printing (components 9-20) was tested, and the results are shown in Table 3 below.

[0144] Table 3. Test results of ink stripper performance for inkjet printing of circuit boards in Comparative Examples 9-20

[0145]

[0146] As shown in Table 3, the difference between Comparative Examples 9-13 and Example 1 lies in the fact that the individual components of the ink stripper, co-solvent, accelerator, emulsifier, and protectant in the ink stripper for PCB inkjet printing are all below the lower limit of the mass concentration specified in this invention. The test results show that, compared with Example 1, if the concentrations of the stripper, co-solvent, accelerator, emulsifier, and protectant are too low, it will affect the ink stripping effect, resulting in ink residue, white spots and ripples on the substrate, and severe corrosion of the copper surface. This is because the effective components in the stripper are too low to achieve the effect of completely stripping the ink. Therefore, the concentration of each component in the ink stripper for PCB inkjet printing of this invention should not be too low. Within the concentration range of the examples, the stable stripping of ink by the ink stripper and the integrity of the PCB substrate surface and copper surface can be ensured at the same time.

[0147] The difference between Comparative Example 14 and Example 1 is that the mass ratio of the co-solvent to the stripper is not within the range specified in this invention. The test results show that although there is no ink residue after stripping and no copper surface corrosion occurs, it leads to technical problems such as white spots and ripples on a few substrates. This is because an excessive amount of the component will interfere with the function of the other component. Therefore, it is necessary to control the mass ratio of the co-solvent to the stripper to be within the range of 1:(0.5-2) to ensure the stable stripping of ink by the ink stripper.

[0148] The difference between Comparative Example 15 and Example 1 is that the stripping agent used is replaced with an equal mass concentration of ethylene glycol butyl ether acetate; the difference between Comparative Example 16 and Example 1 is that the cosolvent used is replaced with an equal mass concentration of proline-proline hydrochloride; the difference between Comparative Example 17 and Example 1 is that the accelerator used is replaced with an equal mass concentration of 1-tetrahydronaphthone; the difference between Comparative Example 18 and Example 1 is that the emulsifier used is replaced with an equal mass concentration of N-(tert-butyloxycarbonyl)phosphatidylaminophosphate diethyl ester; the difference between Comparative Example 19 and Example 1 is that the protective agent used is replaced with an equal mass concentration of benzotriazole. Experimental data show that stripping agents, cosolvents, accelerators, emulsifiers, and protective agents with different types of branched functional groups also affect the ink stripping performance. This is due to the different functions of different functional groups, the mutual activation and passivation effects between different branched functional groups and the main chain, and steric hindrance.

[0149] The difference between Comparative Example 20 and Example 1 is that the prior art circuit board ink stripper is used. Experimental data shows that, compared with Comparative Example 20, the circuit board inkjet printing ink stripper of the present invention has better ink stripping ability, can strip inkjet printing inks, and does not damage the circuit board. No ripples or corrosion occur on the substrate and copper.

[0150] In summary, the ink stripper for inkjet printing of circuit boards provided by this invention, its preparation method, and its application contain effective components such as stripping agents, co-solvents, accelerators, emulsifiers, and protectants. This method replaces the traditional high-temperature, strong-alkali ink stripping method, has excellent ink stripping function, and the stripping process has a lower temperature. The effective components do not damage the substrate or the copper on the circuit, which can greatly reduce the probability of circuit board scrap and has good application prospects.

[0151] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A stripping agent for inkjet printing on circuit boards, characterized in that, It consists of the following components in mass concentration: The composition of the product is as follows: stripping agent 1.5-7.0%, cosolvent 1.0-5.0%, accelerator 1.0-3.0%, emulsifier 1.0-5.5%, protectant 0.2-2.7%, and the balance is water. The stripping agent is selected from one or more of 4-nitrophenyl trifluoroacetate, 2-methylcyclohexyl acetate, and ethylene glycol phenyl ether acetate; The co-solvent is selected from one or more of N-benzyloxycarbonyl-L-proline, trans-4-hydroxy-D-proline, and trans-4-amino-L-proline; The accelerator is selected from one or more of 7-amino-α-tetrahydronaphthone, 8-amino-1-tetrahydronaphthone, and 6-amino-1-tetrahydronaphthone; The emulsifier is selected from one or more of N-(tert-butoxycarbonyl)glycine ethyl ester, N-tert-butoxycarbonyl-D-threonine methyl ester, and N-(tert-butoxycarbonyl)-D-serine β-lactone; The protective agent is selected from one or more of 2-nitroiminoimidazoline, 1,3-dimethyl-2-(2-thienyl)imidazoline, and 2,2-difluoro-1,3-dimethyl-imidazoline; The mass ratio of the co-solvent to the stripping agent is 1:(0.5-2).

2. The ink stripper for circuit board inkjet printing as described in claim 1, characterized in that, The mass concentration of the stripping agent is 2.0-6.0%.

3. The ink stripper for circuit board inkjet printing as described in claim 1, characterized in that, The mass concentration of the co-solvent is 1.5-4.0%.

4. The ink stripper for circuit board inkjet printing as described in claim 1, characterized in that, The mass concentration of the accelerator is 1.5-3.0%.

5. The ink stripper for circuit board inkjet printing as described in claim 1, characterized in that, The mass concentration of the emulsifier is 1.5-5.5%.

6. The ink stripper for circuit board inkjet printing as described in claim 1, characterized in that, The mass concentration of the protective agent is 0.5-2.5%.

7. The ink stripper for circuit board inkjet printing as described in claim 1, characterized in that, It consists of the following components in mass concentration: The composition is as follows: stripping agent 2.0-6.0%, cosolvent 1.5-4.0%, accelerator 1.5-3.0%, emulsifier 1.5-5.5%, protectant 0.5-2.5%, and the balance is water.

8. The method for preparing the ink stripper for inkjet printing of circuit boards as described in any one of claims 1-7, characterized in that, Includes the following steps: Weigh out the stripping agent, cosolvent, accelerator, emulsifier, protectant and water in sequence, and stir and mix them at room temperature of 25℃ for 15-20 minutes to obtain the ink stripping agent for circuit board inkjet printing.

9. A method for removing ink from printed circuit boards, characterized in that, Includes the following steps: S1. First water wash; S2. Alkali wash; S3. Second water wash; S4. Stripping; S5. Third water wash; S6. Drying; wherein, step S4 is to use the ink stripper for inkjet printing of circuit boards as described in any one of claims 1-7 to strip the ink from the printed circuit board.

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