PCB inkjet printing ink stripper, and preparation method and application thereof

Abstract

The application discloses a PCB inkjet printing ink stripping agent, a preparation method and application, and relates to the technical field of inkjet printing circuit board manufacturing. The PCB inkjet printing ink stripping agent comprises the following components with the following mass concentrations: a penetrating agent 3.0-6.0%; an assisting penetrating agent 2.0-4.0%; an accelerating agent 1.0-2.0%; a wetting agent 0.5-1.5%; and a protective agent 0.2-0.6%. The PCB inkjet printing ink stripping agent and the application replace the traditional high-temperature strong-alkali ink stripping method, have excellent ink stripping function, the temperature of the stripping process is relatively low, the effective components do not damage the copper on the substrate and the circuit, and the probability of circuit board scrapping can be greatly reduced.

Description

Technical Field

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

[0002] As electronic products evolve towards miniaturization, lightweighting, high density, and flexibility, the manufacturing process of printed circuit boards (PCBs) is also continuously iterating and upgrading. Inkjet printing technology, with its outstanding advantages such as non-contact processing, fully digital control, high-precision molding, no need for plate making, and high flexibility, is increasingly widely used in PCB manufacturing. Among them, inkjet printing solder resist ink technology is developing rapidly and is gradually replacing traditional screen printing and exposure development processes.

[0003] The traditional PCB solder mask process involves board entry → board grinding → screen printing solder mask → pre-baking → alignment exposure → development → QC inspection → character printing → post-baking → QC inspection. This process is not only complex and lengthy, but also susceptible to ink quality defects due to multiple factors. In contrast, inkjet printing technology, leveraging the digital nature of the entire manufacturing process, has gained widespread acceptance in the PCB industry. This technology boasts three major advantages: high quality, low cost, and environmental friendliness. Requiring only three steps—pre-treatment → inkjet printing → post-curing—it significantly reduces production line footprint, lowers equipment investment, and substantially saves labor costs for customers, thus having the potential to gradually replace the traditional screen printing solder mask process.

[0004] However, inkjet printing has extremely stringent requirements regarding ink type, equipment printing parameter configuration, and pretreatment processes. Improper adaptation in any step can lead to ink diffusion, significant printing line deviations, and ink stripping after baking, resulting in defective products or even scrap, directly increasing production costs for enterprises. Therefore, it is necessary to develop a highly efficient stripping agent specifically for inkjet printing inks. This agent can remove ink from scrapped boards, enabling the recycling and reuse of defective products and effectively controlling costs.

[0005] The composition of inkjet printing inks (such as resin, pigment, solvent, etc.) is fundamentally different from that of traditional inks. This exposes many drawbacks of the traditional high-temperature strong alkali stripping method: not only is the stripping time long and inefficient, but it may also result in incomplete stripping. Moreover, this method is prone to causing deformation, warping, delamination and copper corrosion of PCB substrates, resulting in a scrap rate of 25%-60% for circuit boards.

[0006] Patent CN114980550B discloses a circuit board ink stripping agent and a method for removing circuit board ink. This ink stripping agent relies on the principle of "like dissolves like," causing the ink to swell and eventually break off from the circuit board, thus achieving the effect of removing the ink. It also boasts high stripping efficiency and protects copper from corrosion. The ink stripping time is 150 minutes, and the stripping temperature is 50-60℃. Patent application CN118406404A discloses a circuit board inkjet printing ink stripping agent, its preparation method, and its application. This ink stripping agent, through the synergistic effect of the stripping agent, co-solvent, accelerator, emulsifier, and protectant, can effectively remove inkjet printing ink, reducing the probability of circuit board scrap. The ink stripping time is 10 minutes, and the stripping temperature is 50℃.

[0007] Existing ink stripping agents have good ink removal effects on both conventional inks and printing-specific inks, solving problems such as PCB substrate deformation, warping, delamination, and copper corrosion during ink stripping. However, they still have some drawbacks: existing ink stripping technologies have high stripping temperatures, long stripping times, and low efficiency, increasing production costs. Moreover, prolonged high-temperature stripping can also have adverse effects on the PCB board.

[0008] Therefore, to address the above pain points, there is an urgent need to develop a novel low-temperature ink stripper for PCB inkjet printing. This stripper should achieve efficient, rapid, and thorough stripping of inkjet printing ink at significantly reduced operating temperatures, while minimizing damage to the PCB substrate and metal circuitry. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides a PCB inkjet printing ink stripper, comprising a penetrant, a penetration enhancer, an accelerator, a wetting agent, and a protective agent. The objective of this invention is specifically achieved through the following technical solution to solve the aforementioned technical problems.

[0010] A PCB inkjet printing ink stripper is provided, comprising the following components by mass concentration:

[0011] Penetrant 3.0-6.0%;

[0012] Penetration enhancer 2.0-4.0%;

[0013] Accelerator 1.0-2.0%;

[0014] Wetting agent 0.5-1.5%;

[0015] Protectant 0.2-0.6%;

[0016] The penetrant is selected from one or a mixture of more of the following: triethyl 2-fluoro-2-phosphorylacetate (CAS No.: 2356-16-3), methyl 3-fluoro-4-carboxybenzoate (CAS No.: 74733-25-8), and methyl 3-fluoro-5-carboxybenzoate (CAS No.: 1393561-99-3);

[0017] The penetration enhancer is selected from one or a mixture of more than one of 2-(4-benzoyl-3-hydroxyphenoxy) acrylate (CAS No.: 16432-81-8), 2-(4-hydroxyphenoxy) propionate (CAS No.: 65343-67-1), and 2-(4-hydroxyphenoxy) methyl acetate (CAS: 70067-75-3);

[0018] The accelerator is selected from one or a mixture of more of the following: 2-amino-6-(trifluoromethyl)benzyl alcohol (CAS No.: 763027-00-5), α-(methylaminomethyl)benzyl alcohol (CAS No.: 6589-55-5), and 5-amino-2-fluorobenzyl alcohol (CAS No.: 84832-00-8);

[0019] The wetting agent is selected from one or a mixture of more of the following: 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether (CAS No.: 26675-46-7), chloromethyl trifluoromethyl sulfide (CAS No.: 460-58-2), and 2-chloro-1,1,2-trifluoroethyl difluoromethyl ether (CAS No.: 13838-16-9);

[0020] The protective agent is selected from one or a mixture of more of the following: 2-phenyl-4-trifluoromethylimidazole (CAS No.: 33469-36-2), 1-(trifluoroacetyl)imidazole (CAS No.: 1546-79-8), and 4-(4-fluorophenyl)-1H-imidazole (CAS No.: 65020-70-4).

[0021] Preferably, the PCB inkjet printing ink stripper consists of components with the following mass concentrations:

[0022] Penetrant 3.0-6.0%;

[0023] Penetration enhancer 2.0-4.0%;

[0024] Accelerator 1.0-2.0%;

[0025] Wetting agent 0.5-1.5%;

[0026] Protectant 0.2-0.6%;

[0027] The remainder is water.

[0028] More preferably, the PCB inkjet printing ink stripper is composed of the following components at the following mass concentrations:

[0029] Penetrant 4.0%;

[0030] Penetration enhancer 3.0%;

[0031] Accelerator 1.5%;

[0032] Wetting agent 1.0%;

[0033] Protectant 0.4%;

[0034] The remainder is water.

[0035] The above-mentioned method for preparing PCB inkjet printing ink stripper involves weighing the penetrant, penetrant aid, accelerator, wetting agent, and protective agent in sequence according to the proportions of each component, adding them to water, and mixing them evenly at room temperature.

[0036] The application of the PCB inkjet printing ink stripper of the present invention includes the following steps: soaking and / or spraying the inkjet-printed PCB with the PCB inkjet printing ink stripper.

[0037] Preferably, the application of the PCB inkjet printing ink stripper includes the following steps in sequence:

[0038] Remove section 1: Immerse the inkjet-printed PCB in the PCB inkjet printing ink remover for 1.5-2.5 minutes;

[0039] Remove 2 sections: Spray the inkjet-printed PCB after removing 1 section with the PCB inkjet printing ink stripper for 5-8 minutes at a spraying pressure of 1.5±0.5kg / cm2.

[0040] Remove 3 sections: Immerse the inkjet-printed PCB after removing 2 sections in the PCB inkjet printing ink stripping agent described above for 1.5-2.5 minutes.

[0041] Preferably, the temperature of the PCB inkjet printing ink stripper is 30±0.5℃.

[0042] In some specific embodiments, the application of the PCB inkjet printing ink stripper includes the following steps in sequence:

[0043] Stripping Section 1: The inkjet-printed PCB is immersed in the PCB inkjet printing ink stripping agent described above. The specific process is as follows: immersion method, tank length 1.0m, line speed 0.5±0.1m / min, tank temperature 30±0.5℃;

[0044] Stripping Section 2: The inkjet-printed PCB after section 1 stripping is sprayed with the PCB inkjet printing ink stripping agent. The specific process is as follows: spraying method, tank length 3.0m, line speed 0.5±0.1m / min, tank temperature 30±0.5℃, pressure 1.5±0.5kg / cm2.

[0045] Stripping 3 sections: The inkjet-printed PCB after stripping 2 sections is immersed in the PCB inkjet printing ink stripping agent. The specific process is as follows: immersion method, tank length 1.0m, line speed 0.5±0.1m / min, tank temperature 30±0.5℃.

[0046] Furthermore, before the first section is removed, a water washing process is also included, in which the inkjet-printed PCB is washed with tap water.

[0047] Furthermore, after the removal of the three segments, a water washing process and a drying process are also included in sequence.

[0048] In the PCB inkjet printing ink stripper components of this invention, the penetrant is the most important component for stripping effect. It primarily utilizes the strong electron-withdrawing effect of the fluorine acyl group to make the carbonyl carbon positively charged, causing a nucleophilic substitution reaction with the ester bonds in the ink resin, breaking the resin's cross-linking structure. Simultaneously, the high electronegativity of the fluorine atom reduces surface energy, promoting ink swelling and dispersion. The penetrant aids in ink stripping; its hydrophobic phenoxy structure allows it to penetrate into the ink, disrupting the resin's cross-linking network. Furthermore, the hydroxyl group enhances the interaction with the polar groups in the ink through hydrogen bonding, improving dissolution efficiency. The accelerator involves an addition reaction between the amino group and groups in the ink, promoting resin chain breakage. Simultaneously, the fluorine atom and hydroxyl groups promote ink swelling and dispersion. The wetting agent reduces surface tension, accelerates the reaction rate between the ink and the solution, and improves stripping efficiency. Protective agents can protect circuit boards by adsorbing onto the copper surface through coordination during ink stripping, forming a passivation film, inhibiting the corrosion of copper by hydroxide ions, and reacting with hydroxyl groups on the substrate surface to generate stable chelates, preventing substrate delamination and corrosion, maintaining the integrity of the circuit. At the same time, these compounds can also reduce surface tension.

[0049] The PCB inkjet printing ink stripper and its application of the present invention replace the traditional method of removing ink with high temperature (50-60℃) strong alkali. It has excellent ink stripping function, and the stripping process temperature is relatively low (30±5℃). The effective components do not damage the substrate and the copper on the circuit, which can greatly reduce the probability of circuit board scrap and has good application prospects. Attached Figure Description

[0050] 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.

[0051] Figure 1 This is an optical microscope image of the PCB after the ink has been removed in Example 1.

[0052] Figure 2 This is an optical microscope image of the PCB after the ink has been removed, as shown in Comparative Example 16.

[0053] Figure 3 This is an optical microscope image of the PCB after the ink has been removed in Example 1.

[0054] Figure 4 This is an optical microscope image of the PCB after ink removal, as shown in Comparative Example 16. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0056] It should be noted that the contents or concentrations mentioned in the following examples / comparative examples are all mass concentrations.

[0057] The preparation method of the PCB inkjet printing ink stripper in Examples 1-5 is as follows: According to the formula of Examples 1-5, the penetrant, penetrant aid, accelerator, wetting agent, protective agent and the remaining water are weighed in sequence and added to the reaction vessel. The mixture is stirred and mixed at room temperature for 30 minutes to obtain the PCB inkjet printing ink stripper of the corresponding example. The obtained PCB inkjet printing ink stripper is sealed and stored in a dry place at room temperature for later use.

[0058] Example 1

[0059] The PCB inkjet printing ink stripper of this embodiment consists of the following components:

[0060] The penetrant content is 4.0%, specifically triethyl 2-fluoro-2-phosphorylacetate;

[0061] The penetration enhancer content is 3.0%, specifically ethyl 2-(4-benzoyl-3-hydroxyphenoxy)acrylate;

[0062] The accelerator content is 1.5%, specifically 2-amino-6-(trifluoromethyl)benzyl alcohol;

[0063] The wetting agent content is 1.0%, specifically 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether;

[0064] The protective agent content is 0.4%, specifically 2-phenyl-4-trifluoromethylimidazole;

[0065] The remainder is water.

[0066] Example 2

[0067] The PCB inkjet printing ink stripper of this embodiment consists of the following components:

[0068] The penetrant content is 4.0%, specifically methyl 3-fluoro-4-carboxybenzoate;

[0069] The penetration enhancer content is 3.0%, specifically ethyl 2-(4-hydroxyphenoxy)propionate;

[0070] The accelerator content is 1.5%, specifically α-(methylaminomethyl)benzyl alcohol;

[0071] The wetting agent content is 1.0%, specifically chloromethyltrifluoromethyl sulfide;

[0072] The protective agent content is 0.4%, specifically 1-(trifluoroacetyl)imidazole;

[0073] The remainder is water.

[0074] Example 3

[0075] The PCB inkjet printing ink stripper of this embodiment consists of the following components:

[0076] The penetrant content is 4.0%, specifically 3-fluoro-5-formylbenzoic acid;

[0077] The penetration enhancer content is 3.0%, specifically methyl 2-(4-hydroxyphenoxy)acetate;

[0078] The accelerator content is 1.5%, specifically 5-amino-2-fluorobenzyl alcohol;

[0079] The wetting agent content is 1.0%, specifically 2-chloro-1,1,2-trifluoroethyl difluoromethyl ether;

[0080] The protective agent content is 0.4%, specifically 4-(4-fluorophenyl)-1H-imidazole;

[0081] The remainder is water.

[0082] Example 4

[0083] The PCB inkjet printing ink stripper of this embodiment consists of the following components:

[0084] The penetrant content is 3.0%, specifically triethyl 2-fluoro-2-phosphorylacetate;

[0085] The penetration enhancer content is 2.0%, specifically ethyl 2-(4-benzoyl-3-hydroxyphenoxy)acrylate;

[0086] The accelerator content is 1.0%, specifically 2-amino-6-(trifluoromethyl)benzyl alcohol;

[0087] The wetting agent content is 0.5%, specifically 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether;

[0088] The protective agent content is 0.2%, specifically 2-phenyl-4-trifluoromethylimidazole;

[0089] The remainder is water.

[0090] Example 5

[0091] The PCB inkjet printing ink stripper of this embodiment consists of the following components:

[0092] The penetrant content is 6.0%, specifically triethyl 2-fluoro-2-phosphorylacetate;

[0093] The penetration enhancer content is 4.0%, specifically ethyl 2-(4-benzoyl-3-hydroxyphenoxy)acrylate;

[0094] The accelerator content is 2.0%, specifically 2-amino-6-(trifluoromethyl)benzyl alcohol;

[0095] The wetting agent content is 1.6%, specifically 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether;

[0096] The protective agent content is 0.6%, specifically 2-phenyl-4-trifluoromethylimidazole;

[0097] The remainder is water.

[0098] Based on Example 1, ink strippers for Comparative Examples 1-15 were prepared; in addition, ink stripper for Comparative Example 16 was prepared.

[0099] Comparative Example 1

[0100] The only difference between Comparative Example 1 and Example 1 is that the components do not contain a penetrant.

[0101] Comparative Example 2

[0102] The only difference between Comparative Example 2 and Example 1 is that the components do not contain a penetration enhancer.

[0103] Comparative Example 3

[0104] The only difference between Comparative Example 3 and Example 1 is that the components do not contain accelerators.

[0105] Comparative Example 4

[0106] The only difference between Comparative Example 4 and Example 1 is that the components do not contain a wetting agent.

[0107] Comparative Example 5

[0108] The only difference between Comparative Example 5 and Example 1 is that the components do not contain a protective agent.

[0109] Comparative Example 6

[0110] The only difference between Comparative Example 6 and Example 1 is that the concentration of the penetrant in the component is 9.0%.

[0111] Comparative Example 7

[0112] The only difference between Comparative Example 7 and Example 1 is that the concentration of the penetration enhancer in the component is 6.0%.

[0113] Comparative Example 8

[0114] The only difference between Comparative Example 8 and Example 1 is that the accelerator concentration in the component is 4.0%.

[0115] Comparative Example 9

[0116] The only difference between Comparative Example 9 and Example 1 is that the concentration of wetting agent in the components is 3.0%.

[0117] Comparative Example 10

[0118] The only difference between Comparative Example 10 and Example 1 is that the concentration of the protective agent in the component is 1.2%.

[0119] Comparative Example 11

[0120] The only difference between Comparative Example 11 and Example 1 is that the penetrant was replaced with an equal mass concentration of 4-nitrophenyl trifluoroacetate (CAS No.: 658-78-6).

[0121] Comparative Example 12

[0122] The only difference between Comparative Example 12 and Example 1 is that the penetration enhancer was replaced with an equal mass concentration of ethyl 4-phenoxybutyrate (CAS No.: 2364-59-2).

[0123] Comparative Example 13

[0124] The only difference between Comparative Example 13 and Example 1 is that the accelerator was replaced with an equal mass concentration of 2-methylbenzyl alcohol (CAS No.: 89-95-2).

[0125] Comparative Example 14

[0126] The only difference between Comparative Example 14 and Example 1 is that the wetting agent was replaced with an equal mass concentration of poly(perfluoromethyl isopropyl ether) (CAS No.: 69991-67-9).

[0127] Comparative Example 15

[0128] The only difference between Comparative Example 15 and Example 1 is that the protective agent was replaced with an equal mass concentration of benzotriazole (CAS No.: 95-14-7).

[0129] Comparative Example 16

[0130] Comparative Example 16 is the ink stripper described in prior art CN118406404A, and its specific components include:

[0131] The stripping agent is 6.0%, specifically ethylene glycol phenyl ether acetate;

[0132] The cosolvent is 4.0%, specifically trans-4-hydroxy-D-proline;

[0133] Accelerator 3.0%, specifically 7-amino-α-tetrahydronaphthone;

[0134] The emulsifier is 5.5%, specifically N-(tert-butyloxycarbonyl)glycine ethyl ester;

[0135] The protective agent is 2.5%, specifically 2,2-difluoro-1,3-dimethyl-imidazolidine;

[0136] The remainder is water.

[0137] The PCB inkjet printing ink stripper of the above embodiments and the ink stripper of the comparative example are respectively applied to the removal of inkjet printing ink, including the following steps: S1 water washing; S2 stripping 1 section; S3 stripping 2 sections; S4 stripping 3 sections; S5 water washing; S6 drying;

[0138] The S1 water washing process involves washing the PCBs that require inkjet printing ink removal with tap water. The process parameters for this water washing process are as follows: spray method, bath temperature 25±0.5℃, water washing tank length 1.0m; linear velocity 2.0±0.1m / min, pressure 1.5±0.5kg / cm. 2 ;

[0139] The S2 stripping step 1 involves using the ink stripping agent prepared in the above embodiment or comparative ratio to strip the inkjet printing ink from the PCB that has undergone the S1 water washing step; the process parameters for the stripping step 1 are: immersion method, tank length 1.0m, linear speed 0.5±0.1m / min, and tank temperature 30±0.5℃.

[0140] The S3 stripping step 2 involves using the ink stripping agent prepared in the above embodiment or comparative example to strip the inkjet printing ink from the PCB that has undergone the S2 stripping step 1. The process parameters for the stripping step 2 are: spray method, tank length 3.0m, linear speed 0.5±0.1m / min, temperature 30±0.5℃, and pressure 1.5±0.5kg / cm. 2 ;

[0141] The S4 stripping step 3 involves using the ink stripping agent prepared in the above embodiment or comparative example to strip the inkjet printing ink from the PCB that has undergone the S3 stripping step 2 process. The process parameters for the stripping step 3 process are: immersion method, tank length 1.0m, linear speed 0.5±0.1m / min, and temperature 30±0.5℃.

[0142] The S5 water washing process involves rinsing the PCB, which has undergone the three-stage stripping process in S4, with tap water. The process parameters for this water washing process are as follows: spray method, tank length 1.0m, temperature 25±0.5℃, linear speed 2.0±0.1m / min, and pressure 1.5±0.2kg / cm. 2 ;

[0143] The S6 drying process involves drying the PCB that has undergone the S5 water washing process. The process parameters for the drying section are: drying temperature 75±5℃ and drying time 1±0.2min.

[0144] The ink removal degree and substrate damage were tested on the PCBs with inkjet printing ink removed in the above embodiments / comparative examples. Ink removal degree: The surface of the circuit board after ink removal was observed using a metallographic microscope to determine if there was any ink residue. Substrate damage: The substrate surface of the circuit board after ink removal was observed to determine if there were any white spots or ripples, thus assessing whether ink removal affected the substrate.

[0145] The copper surface corrosion degree of the ink stripping agents in the above examples / comparative examples was tested to detect the degree of corrosion of the copper surface by the ink stripping agents. Specifically, a copper-clad laminate with dimensions of 4cm x 5cm and a copper thickness of 18μm was weighed using an electronic balance. The copper-clad laminate was then processed according to the three-stage stripping process described above. After removing the copper-clad laminate, the copper surface etching time (min) was recorded. After washing and drying, it was weighed again. The copper surface etching rate was calculated as weight difference (g) * 28 / etching time, in μm / min. The etching rate was required to be ≤0.5μm / min (preferably ≤0.3μm / min).

[0146] The test results are shown in Table 1 below.

[0147] Table 1 Test Results

[0148]

[0149] Example 1: Optical microscopic observation results of the PCB after ink removal. Figure 1 and Figure 3 As shown in the figure. The optical microscope observation results of the PCB after ink removal in Comparative Example 16 are as follows. Figure 2 and Figure 4 As shown.

[0150] As can be seen from the test results of Examples 1-5 in Table 1, the PCB inkjet printing ink remover of Examples 1-5 of the present invention can efficiently remove inkjet printing ink from PCBs at low temperature (30±0.5℃). After ink removal, there is no ink residue on the PCB surface, no white spots or ripples are exposed on the substrate, the copper surface etching rate is ≤0.08μm / min, and the PCB remains basically intact. Therefore, the PCB inkjet printing ink remover of the present invention can achieve efficient and thorough ink removal at a low temperature of 30℃, while protecting the copper surface and substrate surface, achieving a balance between efficient low-temperature removal and material safety.

[0151] The difference between Comparative Examples 1-5 and Example 1 lies in the fact that the PCB inkjet printing ink stripper formulation provided by this invention omits one of the following components: penetrant, penetration enhancer, accelerator, wetting agent, and protectant. Test results show that the stripper, as the core functional component of this ink stripping system, is significantly affected by its absence, resulting in substantial ink residue and ineffective removal. The penetration enhancer, accelerator, and wetting agent play a synergistic role in the removal of inkjet printing ink; the absence of any one of these components will leave a small amount of ink residue after stripping. The protectant primarily protects the circuit board and effectively prevents substrate corrosion; its absence will cause white spots or wavy corrosion marks on some substrates. Furthermore, the absence of any of the five components increases the etching rate of the copper surface, exacerbating copper corrosion, with the most significant increase observed when the protectant is absent.

[0152] The difference between Comparative Examples 6-10 and Example 1 is that the concentrations of the individual components (including penetrant, penetration enhancer, accelerator, wetting agent, and protectant) exceed the upper limit of the concentration range defined in this invention. Test results show that, compared to Example 1, the excessive addition of these components does not weaken the ink removal ability, and the damage to the copper and substrate surfaces is negligible. This indicates that within the concentration range set by this invention, the stripper already possesses highly efficient ink removal performance. While excessively increasing the component concentration does not affect the removal effect, it will lead to an unnecessary increase in chemical costs. Therefore, the concentrations of each component in the PCB inkjet printing ink stripper of this invention do not need to be too high. Within the concentration range defined in Examples 1-5, excellent ink removal efficiency and the integrity of the circuit board substrate and copper surface can be simultaneously guaranteed.

[0153] The difference between Comparative Examples 11-15 and Example 1 is that the penetrant, penetration enhancer, accelerator, wetting agent, and protectant were replaced with other compounds of equal mass concentration and with similar structures or functions. Test results show that using corresponding functional components with different branched structures or functional group types significantly affects ink removal performance, making it difficult to achieve the low-temperature, rapid, and thorough ink removal effect required by this invention.

[0154] The difference between Comparative Example 16 and Example 1 is that a prior art ink stripping method was used (see Chinese Patent Application CN118406404A). Test results show that, compared to Comparative Example 16, the ink stripper provided by this invention exhibits superior stripping efficiency for inkjet printing inks under low-temperature conditions, and avoids damage to the circuit board substrate and copper surface. No adverse phenomena such as ripples, white spots, or corrosion were observed.

[0155] In summary, the PCB inkjet printing ink stripper and its application provided by this invention contain effective components such as stripper, penetration aid, accelerator, emulsifier, and protectant. This method replaces the traditional high-temperature and strong alkali method for removing ink, has excellent ink removal function, and the removal process has a low temperature. The effective components do not damage the substrate and the copper on the circuit. It can be applied to the process of rapidly removing inkjet printing ink under low-temperature conditions on PCBs.

[0156] 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 PCB inkjet printing ink remover, characterized in that, Components including the following mass concentrations: Penetrant 3.0-6.0%; Penetration enhancer 2.0-4.0%; Accelerator 1.0-2.0%; Wetting agent 0.5-1.5%; Protectant 0.2-0.6%; The penetrant is selected from one or a mixture of more than one of 2-fluoro-2-phosphorylacetate, methyl 3-fluoro-4-carboxybenzoate, and methyl 3-fluoro-5-carboxybenzoate; The penetration enhancer is selected from one or a mixture of more than one of 2-(4-benzoyl-3-hydroxyphenoxy)acrylate, 2-(4-hydroxyphenoxy)propionate, and 2-(4-hydroxyphenoxy)acetic acid methyl ester; The accelerator is selected from one or a mixture of more than one of 2-amino-6-(trifluoromethyl)benzyl alcohol, α-(methylaminomethyl)benzyl alcohol, and 5-amino-2-fluorobenzyl alcohol; The wetting agent is selected from one or a mixture of more than one of 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether, chloromethyl trifluoromethyl sulfide, and 2-chloro-1,1,2-trifluoroethyl difluoromethyl ether; The protective agent is selected from one or a mixture of more of 2-phenyl-4-trifluoromethylimidazole, 1-(trifluoroacetyl)imidazole, and 4-(4-fluorophenyl)-1H-imidazole.

2. The PCB inkjet printing ink remover according to claim 1, characterized in that, It consists of components with the following mass concentrations: Penetrant 3.0-6.0%; Penetration enhancer 2.0-4.0%; Accelerator 1.0-2.0%; Wetting agent 0.5-1.5%; Protectant 0.2-0.6%; The remainder is water.

3. The PCB inkjet printing ink remover according to claim 1, characterized in that, It consists of components with the following mass concentrations: Penetrant 4.0%; Penetration enhancer 3.0%; Accelerator 1.5%; Wetting agent 1.0%; Protectant 0.4%; The remainder is water.

4. The method for preparing the PCB inkjet printing ink stripper as described in any one of claims 1-3, characterized in that, According to the proportions of each group, weigh out the penetrant, penetration enhancer, accelerator, wetting agent, and protectant in sequence, add them to water, and mix them evenly at room temperature to obtain the final product.

5. The application of the PCB inkjet printing ink remover as described in any one of claims 1-3, characterized in that, Includes the following steps: The inkjet-printed PCB is immersed and / or sprayed with the PCB inkjet printing ink stripper described above.

6. The application according to claim 5, characterized in that, The steps are as follows: Remove section 1: Immerse the inkjet-printed PCB in the PCB inkjet printing ink remover for 1.5-2.5 minutes; Stripping Section 2: After section 1 has been removed, the inkjet-printed PCB is sprayed with the described PCB inkjet printing ink stripping agent for 5-8 minutes at a spraying pressure of 1.5 ± 0.5 kg / cm². 2 ; Remove 3 sections: Immerse the inkjet-printed PCB after removing 2 sections in the PCB inkjet printing ink stripping agent described above for 1.5-2.5 minutes.

7. The application according to claim 6, characterized in that, The temperature of the PCB inkjet printing ink stripper is 30±0.5℃.

8. The application according to claim 5, characterized in that, The steps are as follows: Stripping Section 1: The inkjet-printed PCB is immersed in the PCB inkjet printing ink stripping agent described above. The specific process is as follows: immersion method, tank length 1.0m, line speed 0.5±0.1m / min, tank temperature 30±0.5℃; Stripping Section 2: The inkjet-printed PCB after section 1 stripping is sprayed with the aforementioned PCB inkjet printing ink stripping agent. The specific process is as follows: spraying method, tank length 3.0m, linear velocity 0.5±0.1m / min, tank temperature 30±0.5℃, pressure 1.5±0.5kg / cm 2 ; Stripping 3 sections: The inkjet-printed PCB after stripping 2 sections is immersed in the PCB inkjet printing ink stripping agent. The specific process is as follows: immersion method, tank length 1.0m, line speed 0.5±0.1m / min, tank temperature 30±0.5℃.

9. The application according to claim 6, characterized in that, The process of removing one section also includes a water washing process.

10. The application according to claim 9, characterized in that, After the three sections are removed, a washing process and a drying process are performed in sequence.

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