PCB via-filling resin anti-diffusion agent, its preparation method and application method

Abstract

This invention discloses a PCB via-filling resin anti-diffusion agent, its preparation method, and its application method, relating to the field of printed circuit board manufacturing technology. The PCB via-filling resin anti-diffusion agent comprises the following components by weight percentage: main anti-diffusion agent 2.0%-4.0%; synergistic film-forming agent 1.0%-2.0%; surface energy modifier 0.5%-1.0%; adhesion promoter 1.0%-2.0%; and co-solvent 2.0%-6.0%. The PCB via-filling resin anti-diffusion agent provided by this invention is suitable for PCB via-filling resin pretreatment processes, effectively solving the problem of easy diffusion of low-viscosity resins, inhibiting the diffusion behavior of via-filling resin on the copper surface, and exhibiting excellent process reliability, significantly improving the yield of via-filling resin processes.

Description

Technical Field

[0001] This invention relates to the field of printed circuit board (PCB) manufacturing technology, and more specifically, to a PCB via-filling resin anti-diffusion agent, its preparation method, and its application method. Background Technology

[0002] Printed circuit boards (PCBs) are constantly evolving towards high-density interconnects, micro-vias, and high aspect ratios. Resin-filled via technology has become a crucial process for ensuring good electrical performance, heat dissipation, and mechanical stability in high-density interconnect structures. This process involves filling blind vias, buried vias, and through-holes in PCBs with specific resin inks, which then cure to form an insulator. This achieves electrical insulation within the vias, avoids chemical residues, and improves the filling effect during multilayer board lamination.

[0003] However, during the pre-baking and curing process after resin plugging, the surface energy of the printed circuit board substrate is high, and the surface roughening treatment performed before plugging further increases its surface roughness. As a result, under the action of capillary action and surface tension, the resin material is prone to unplanned diffusion from the inside of the target hole to the outside of the hole, thus forming a resin overflow area around the hole opening.

[0004] Such diffusion can lead to various process defects and reliability issues. First, the resin film remaining on the inner wall of non-support holes can affect the uniformity of subsequent chemical etching, potentially resulting in localized residual copper after etching, thus reducing the reliability of electrical connections. Second, overflowing resin can occupy the designated area of ​​the solder mask ink, reducing the thickness of the solder mask pattern edges and compromising the integrity of the solder mask layer. Furthermore, removing the diffused resin requires additional grinding or cleaning steps, increasing process complexity and production time, and consequently raising manufacturing costs.

[0005] In existing technologies, secondary drilling or strong oxidant cleaning are commonly used to suppress resin diffusion. However, these anti-diffusion methods have limitations in terms of effectiveness, cost, and process applicability, making it difficult to meet the precision manufacturing demands of high-density interconnect structures that are evolving towards higher precision and reliability.

[0006] Existing technologies also disclose some technical solutions related to anti-diffusion agents. For example, patent application CN119855060A discloses a PCB inkjet printing pretreatment agent and its preparation method and inkjet printing process. This pretreatment agent contains effective components such as anti-diffusion agents, wetting agents, homogenizers, dispersants, and cosolvents, which can form a uniform organic layer on the copper surface and substrate surface of the PCB. This organic layer can effectively reduce the surface tension between the copper surface and the substrate, inhibit the diffusion of ink on the PCB surface, and promote uniform ink distribution, which is conducive to the formation of stable and regular linear ink, thereby improving the product yield of fine line inkjet printing process. Patent application CN120018406A discloses a fine line pattern anti-diffusion agent and its preparation and application method. This anti-diffusion agent is composed of components such as oleophobic agents, bonding agents, adhesion promoters, wetting agents, and cosolvents, which can form an organic layer on the copper surface of the circuit board, enhance the bonding force between the copper surface and the ink, inhibit the diffusion of ink on the copper surface, and improve the product qualification rate of the inkjet solder resist process.

[0007] Currently, existing technologies offer some solutions to the ink diffusion problem during inkjet printing of ordinary PCB boards. However, anti-diffusion technologies specifically designed for via-filling resins remain scarce. Because via-filling resins differ significantly from inkjet inks in application scenarios, substrate characteristics, system state, and curing methods, existing anti-diffusion agents are insufficient to meet the anti-diffusion process requirements. Therefore, there is an urgent need to develop an anti-diffusion agent suitable for PCB via-filling resins to address the process defects caused by the diffusion of low-viscosity resins during PCB via-filling and improve the yield of low-viscosity via-filling resin processes. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a PCB via-filling resin anti-diffusion agent and its application method, applicable to the pretreatment process of via-filling resin. This anti-diffusion agent comprises a primary anti-diffusion agent, a synergistic film-forming agent, a surface energy modifier, an adhesion promoter, and a co-solvent. The primary anti-diffusion agent can undergo a bonding reaction with the PCB substrate, forming the main framework of the anti-diffusion layer, while simultaneously forming a cross-linked structure with the resin at the other end, providing basic adhesion. The synergistic film-forming agent optimizes interfacial compatibility, improves the structural stability of the composite system, enhances the material's flexural strength and impact resistance, and prevents interfacial debonding. The surface energy modifier significantly reduces the surface free energy of the coating, resulting in a high contact angle for the subsequent via-filling resin, creating a "resin-phobic" effect that inhibits lateral resin spreading. The adhesion promoter forms a strong chemical bond with the PCB substrate at one end and bonds with the resin at the other, significantly improving the anchoring effect of the coating on the via wall, preventing coating peeling and resin penetration. The co-solvent solves the dissolution problem of hydrophobic components in the system, ensuring a homogeneous and stable solution system and guaranteeing process applicability. Through synergistic effects, the components effectively suppress the diffusion of the pore-filling resin on the copper surface, significantly improving the product yield of the pore-filling resin process.

[0009] The objective of this invention is achieved through the following technical solutions.

[0010] A PCB via-sealing resin anti-diffusion agent is provided, comprising the following components by weight percentage:

[0011] Main anti-diffusion agent 2.0%-4.0%; synergistic film-forming agent 1.0%-2.0%; surface energy modifier 0.5%-1.0%; adhesion promoter 1.0%-2.0%; co-solvent 2.0%-6.0%;

[0012] The primary anti-diffusion agent is selected from one or more of tris(vinyldimethylsiloxy)methylsilane (CAS No.: 60111-52-6), vinyltris(trimethylsiloxy)silane (CAS No.: 5356-84-3), and vinyltris(2-methoxyethoxy)silane (CAS No.: 1067-53-4);

[0013] The synergistic film-forming agent is selected from one or more of bis(3-mercaptopropionic acid) ethylene glycol (CAS No.: 22504-50-3), 3-methoxybutylmercaptoacetate (CAS No.: 27431-39-6), and isooctyl 3-mercaptopropionic acid (CAS No.: 30374-01-7);

[0014] The surface energy modifier is selected from one or more of 3-fluorocatechol (CAS No.: 363-52-0), 3-bromocatechol (CAS No.: 14381-51-2), and 3-chlorocatechol (CAS No.: 4018-65-9);

[0015] The adhesion promoter is selected from one or more of the following: heteroazobicyclic phosphate (CAS No.: 90776-59-3), (R)-spirocyclodiol phosphate (CAS No.: 1352810-35-5), and 1-O-hexadecyl-sn-glycerol-2,3-cyclic phosphate (CAS: 799268-68-1);

[0016] The co-solvent is selected from one or more of 2-ethynylcyclopentanol (CAS No.: 22022-30-6), 1-ethynylcyclopentanol (CAS No.: 17356-19-3), and 1-ethynyl-1-cyclohexanol (CAS No.: 78-27-3).

[0017] Preferably, the PCB via-filling resin anti-diffusion agent of the present invention is composed of the following components by weight percentage: main anti-diffusion agent 2.0%-4.0%; synergistic film-forming agent 1.0%-2.0%; surface energy modifier 0.5%-1.0%; adhesion promoter 1.0%-2.0%; co-solvent 2.0%-6.0%; and the balance being water.

[0018] Preferably, the PCB via-filling resin anti-diffusion agent of the present invention is composed of the following components by weight percentage: 3.0% main anti-diffusion agent; 1.5% synergistic film-forming agent; 0.7% surface energy modifier; 1.5% adhesion promoter; 4.0% co-solvent; and the balance being water.

[0019] Preferably, the PCB via-sealing resin anti-diffusion agent of the present invention is composed of the following components by weight percentage: tris(vinyldimethylsiloxy)methylsilane 3.0%; bis(3-mercaptopropionic acid) ethylene glycol 1.5%; 3-fluorocatechol 0.7%; heteroazobiscyclic phosphate 1.5%; 2-ethynylcyclopentanol 4.0%; and the balance being water.

[0020] The preparation method of the above-mentioned PCB hole-filling resin anti-diffusion agent includes the following steps: adding the main anti-diffusion agent, synergistic film-forming agent, surface energy modifier, adhesion promoter and co-solvent into deionized water and mixing them evenly to obtain the PCB hole-filling resin anti-diffusion agent.

[0021] The present invention also provides a method for applying the above-mentioned PCB via-filling resin anti-diffusion agent, wherein the above-mentioned PCB via-filling resin anti-diffusion agent is used as a spray liquid in the anti-diffusion process, and the PCB via-filling resin anti-diffusion agent is sprayed onto the PCB before the resin via-filling process by spraying.

[0022] Preferably, the spray pressure is 1.5 ± 0.5 kg / cm². 2 Spraying time: 30±5 seconds.

[0023] Preferably, the temperature of the spray liquid is 25±0.5℃.

[0024] Furthermore, prior to the anti-proliferation process, a hydrochloric acid washing process and a water washing process are also included in sequence.

[0025] Furthermore, after the anti-diffusion process and before the resin plugging process, a water washing process and a drying process are also included in sequence.

[0026] In some specific embodiments, the application method of the PCB via-filling resin anti-diffusion agent of the present invention includes the following steps in sequence: S1 water washing process; S2 ultra-roughening process; S3 water washing process; S4 hydrochloric acid washing process; S5 water washing process; S6 anti-diffusion process; S7 water washing process; S8 drying process; S9 resin via-filling process; S10 baking process.

[0027] The S1 water washing process involves washing the printed circuit board (PCB) requiring resin plugging with deionized water. The process parameters are as follows: spray method, bath temperature 25±0.5℃, bath length 1.0m; linear velocity 2.0±0.1m / min, pressure 1.5±0.5kg / cm². 2;

[0028] The S2 ultra-roughening process involves using BTH-2085B ultra-roughening solution from Shenzhen Banming Technology Co., Ltd. to pre-treat the printed circuit board after the S1 water washing process. The process parameters for the ultra-roughening process are as follows: the amount of solution added is based on the initial BTH-2085B solution; spraying is used; the bath temperature is 25±0.5℃; the length of the water washing tank is 1.0m; the linear velocity is 1.0±0.1m / min; and the pressure is 1.5±0.5kg / cm. 2 ;

[0029] The S3 water washing process involves washing the printed circuit board that has undergone the S2 ultra-roughening process with deionized water. The process parameters for the 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 ;

[0030] The S4 hydrochloric acid washing process involves cleaning the printed circuit board (PCB) after the S3 water washing process with a hydrochloric acid solution to remove chemical residues from the PCB surface. The process parameters for the hydrochloric acid washing process are as follows: the solution is added at a hydrochloric acid mass fraction of 3.0%, diluted with tap water; a spray method is used; the bath temperature is 25±0.5℃; the washing tank length is 1.0m; the linear velocity is 2.0±0.1m / min; and the pressure is 1.5±0.5kg / cm². 2 ;

[0031] The S5 water washing process involves washing the printed circuit board that has undergone the S4 hydrochloric acid washing process with deionized water. The process parameters for the 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 ;

[0032] The S6 anti-diffusion process involves using the PCB via-filling resin anti-diffusion agent of this invention to treat the printed circuit board after the S5 water washing process to prevent diffusion. The process parameters for the anti-diffusion 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 ;

[0033] The S7 water washing process involves washing the printed circuit board that has undergone the S6 anti-diffusion process with deionized water. The process parameters for the 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 ;

[0034] The S8 drying process is to dry the printed circuit board that has passed the S7 water washing process. The process parameters of the drying section are: drying temperature 75±5℃, drying time 1±0.2min.

[0035] The S9 resin plugging process is to plug the printed circuit board that has passed the S8 drying process. The process parameters of the resin plugging process are as follows: the plugging equipment is a vacuum plugging machine of model DSV-800 produced by Suzhou Shengfeng, and the resin used is from Shenzhen Banming Technology Co., Ltd., model BTH-8000PHP-LV, with a viscosity of 320mPa•s after thawing.

[0036] The S10 baking process involves baking the printed circuit board that has undergone the S9 resin plugging process. The process parameters for the baking process are: baking at 140°C for 60 minutes, then heating to 160°C for 30 minutes, and then removing it and letting it stand at room temperature.

[0037] The PCB via-filling resin anti-diffusion agent provided by this invention can effectively suppress the diffusion of via-filling resin on the copper surface through the synergistic effect of its components, and significantly improve the product yield of the via-filling resin process. Attached Figure Description

[0038] 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.

[0039] Figure 1 The contact angle of the resin on the copper surface after the anti-diffusion process in Example 1;

[0040] Figure 2 The contact angle of the resin on the copper surface after the anti-diffusion process in Comparative Example 16 is shown.

[0041] Figure 3 This is an optical microscope image of a section showing the location of the plug hole in an example.

[0042] Figure 4 This is an optical microscope image of a section at the plug hole location in Comparative Example 16. Detailed Implementation

[0043] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0044] Unless otherwise stated, all contents or concentrations in the following examples and comparative examples are mass concentrations.

[0045] Example 1

[0046] Weigh out the main anti-diffusion agent, synergistic film-forming agent, surface energy modifier, adhesion promoter, co-solvent, and other components in sequence according to the following formula, and add the remaining water to the reaction vessel. Stir and mix at room temperature for 30 minutes to obtain the PCB hole-sealing resin anti-diffusion agent of this embodiment. Store the solution in a sealed container in a dry place at room temperature for later use.

[0047] The main anti-diffusion agent content is 3.0%, specifically tris(vinyldimethylsiloxy)methylsilane;

[0048] The content of the synergistic film-forming agent is 1.5%, specifically bis(3-mercaptopropionic acid) ethylene glycol;

[0049] The surface energy modifier content is 0.7%, specifically 3-fluorocatechol;

[0050] The adhesion promoter content is 1.5%, specifically heteroazo dicyclic phosphate;

[0051] The co-solvent content is 4.0%, specifically 2-ethynylcyclopentanol;

[0052] The remaining water is tap water.

[0053] Example 2

[0054] Weigh out the main anti-diffusion agent, synergistic film-forming agent, surface energy modifier, adhesion promoter, co-solvent, and other components in sequence according to the following formula, and add the remaining water to the reaction vessel. Stir and mix at room temperature for 30 minutes to obtain the PCB hole-sealing resin anti-diffusion agent of this embodiment. Store the solution in a sealed container in a dry place at room temperature for later use.

[0055] The main anti-diffusion agent content is 2.0%, specifically tris(vinyldimethylsiloxy)methylsilane;

[0056] The content of the synergistic film-forming agent is 1.0%, specifically bis(3-mercaptopropionic acid) ethylene glycol;

[0057] The surface energy modifier content is 0.5%, specifically 3-fluorocatechol;

[0058] The adhesion promoter content is 1.0%, specifically heteroazo dicyclic phosphate;

[0059] The co-solvent content is 2.0%, specifically 2-ethynylcyclopentanol;

[0060] The remaining water is tap water.

[0061] Example 3

[0062] Weigh out the main anti-diffusion agent, synergistic film-forming agent, surface energy modifier, adhesion promoter, co-solvent, and other components in sequence according to the following formula, and add the remaining water to the reaction vessel. Stir and mix at room temperature for 30 minutes to obtain the PCB hole-sealing resin anti-diffusion agent of this embodiment. Store the solution in a sealed container in a dry place at room temperature for later use.

[0063] The main anti-diffusion agent content is 4.0%, specifically tris(vinyldimethylsiloxy)methylsilane;

[0064] The content of the synergistic film-forming agent is 2.0%, specifically bis(3-mercaptopropionic acid) ethylene glycol;

[0065] The surface energy modifier content is 1.0%, specifically 3-fluorocatechol;

[0066] The adhesion promoter content is 2.0%, specifically heteroazo dicyclic phosphate;

[0067] The co-solvent content is 6.0%, specifically 2-ethynylcyclopentanol;

[0068] The remaining water is tap water.

[0069] Example 4

[0070] Weigh out the main anti-diffusion agent, synergistic film-forming agent, surface energy modifier, adhesion promoter, co-solvent, and other components in sequence according to the following formula, and add the remaining water to the reaction vessel. Stir and mix at room temperature for 30 minutes to obtain the PCB hole-sealing resin anti-diffusion agent of this embodiment. Store the solution in a sealed container in a dry place at room temperature for later use.

[0071] The main anti-diffusion agent content is 3.0%, specifically vinyltris(trimethylsiloxy)silane;

[0072] The content of the synergistic film-forming agent is 1.5%, specifically 3-methoxybutyl mercaptoacetic acid ester;

[0073] The surface energy modifier content is 0.7%, specifically 3-bromocatechol;

[0074] The adhesion promoter content is 1.5%, specifically (R)-spirocyclic diol phosphate;

[0075] The co-solvent content is 3.0%, specifically 1-ethynylcyclopentanol;

[0076] The remaining water is tap water.

[0077] Example 5

[0078] Weigh out the main anti-diffusion agent, synergistic film-forming agent, surface energy modifier, adhesion promoter, co-solvent, and other components in sequence according to the following formula, and add the remaining water to the reaction vessel. Stir and mix at room temperature for 30 minutes to obtain the PCB hole-sealing resin anti-diffusion agent of this embodiment. Store the solution in a sealed container in a dry place at room temperature for later use.

[0079] The main anti-diffusion agent content is 3.0%, specifically vinyltris(2-methoxyethoxy)silane;

[0080] The content of the synergistic film-forming agent is 1.5%, specifically isooctyl 3-mercaptopropionate;

[0081] The surface energy modifier content is 0.7%, specifically 3-chlorocatechol;

[0082] The adhesion promoter content is 1.5%, specifically 1-O-hexadecyl-sn-glycerol-2,3-cyclic phosphate;

[0083] The co-solvent content is 3.0%, specifically 1-ethynyl-1-cyclohexanol;

[0084] The remaining water is tap water.

[0085] Comparative Example 1

[0086] The only difference between Comparative Example 1 and Example 1 is that the components do not contain a primary anti-diffusion agent.

[0087] Comparative Example 2

[0088] The only difference between Comparative Example 2 and Example 1 is that the components do not contain a synergistic film-forming agent.

[0089] Comparative Example 3

[0090] The only difference between Comparative Example 3 and Example 1 is that the components do not contain surface energy modifiers.

[0091] Comparative Example 4

[0092] The only difference between Comparative Example 4 and Example 1 is that the components do not contain adhesion promoters.

[0093] Comparative Example 5

[0094] The only difference between Comparative Example 5 and Example 1 is that the components do not contain a cosolvent.

[0095] Comparative Example 6

[0096] The only difference between Comparative Example 6 and Example 1 is that the concentration of the main anti-diffusion agent in the component is 8.0%.

[0097] Comparative Example 7

[0098] The only difference between Comparative Example 7 and Example 1 is that the concentration of the synergistic film-forming agent in the components is 4.0%.

[0099] Comparative Example 8

[0100] The only difference between Comparative Example 8 and Example 1 is that the concentration of the surface energy modifier in the component is 2.0%.

[0101] Comparative Example 9

[0102] The only difference between Comparative Example 9 and Example 1 is that the concentration of adhesion promoter in the component is 4.0%.

[0103] Comparative Example 10

[0104] The only difference between Comparative Example 10 and Example 1 is that the concentration of the cosolvent in the component is 8.0%.

[0105] Comparative Example 11

[0106] The only difference between Comparative Example 11 and Example 1 is that the main anti-diffusion agent was replaced with an equal mass concentration of methoxydimethyl(phenyl)silane (CAS No.: 17881-88-8).

[0107] Comparative Example 12

[0108] The only difference between Comparative Example 12 and Example 1 is that the synergistic film-forming agent was replaced with an equal mass concentration of cyclohexylmethyl acetate (CAS No.: 937-55-3).

[0109] Comparative Example 13

[0110] The only difference between Comparative Example 13 and Example 1 is that the surface energy modifier was replaced with an equal mass concentration of 4-octylcatechol (CAS No.: 7580-46-3).

[0111] Comparative Example 14

[0112] Comparative Example 14 differs from Example 1 only in that the adhesion promoter is replaced with an equal mass concentration of dodecyl phosphate (CAS No.: 2627-35-2).

[0113] Comparative Example 15

[0114] The only difference between Comparative Example 15 and Example 1 is that the cosolvent was replaced with an equal mass concentration of cyclopentanol (CAS No.: 96-41-3).

[0115] Comparative Example 16

[0116] This comparative example uses an anti-diffusion agent from the prior art (Chinese patent application CN120018406A), specifically, its components include:

[0117] The oleophobic agent content is 0.1%, specifically o-fluorophenylethylamine;

[0118] The bonding agent content is 0.3%, specifically 2-propylthiopyridine-3-carbonyl chloride;

[0119] The adhesion promoter content is 0.5%, specifically 2,2-dimethylthionylpropane;

[0120] The wetting agent content is 1.5%, specifically vinyltris(dimethylsiloxane)silane;

[0121] The co-solvent content is 1.5%, specifically 1-N-methanesulfonyl-4-piperidinone;

[0122] The remainder is water.

[0123] The PCB via-filling resin anti-diffusion agent of the above embodiments or comparative examples is applied to the PCB via-filling resin anti-diffusion process. The process flow is as follows: S1 water washing process; S2 ultra-roughening process; S3 water washing process; S4 hydrochloric acid washing process; S5 water washing process; S6 anti-diffusion process; S7 water washing process; S8 drying process; S9 resin via-filling process; S10 baking process. Details are as follows.

[0124] The S1 water washing process involves washing the printed circuit board (PCB) requiring resin plugging with deionized water. The process parameters are as follows: spray method, bath temperature 25±0.5℃, bath length 1.0m; linear velocity 2.0±0.1m / min, pressure 1.5±0.5kg / cm². 2 ;

[0125] The S2 ultra-roughening process involves using BTH-2085B ultra-roughening solution from Shenzhen Banming Technology Co., Ltd. to pre-treat the printed circuit board after the S1 water washing process. The process parameters for the ultra-roughening process are as follows: the amount of solution added is based on the initial BTH-2085B solution; spraying is used; the bath temperature is 25±0.5℃; the length of the water washing tank is 1.0m; the linear velocity is 1.0±0.1m / min; and the pressure is 1.5±0.5kg / cm. 2 ;

[0126] The S3 water washing process involves washing the printed circuit board (PCB) after the S2 ultra-roughening process with deionized water. The process parameters for this water washing process are: 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 / cm². 2 ;

[0127] The S4 hydrochloric acid washing process involves cleaning the printed circuit board (PCB) after the S3 water washing process with a hydrochloric acid solution to remove chemical residues from the PCB surface. The process parameters for the hydrochloric acid washing process are as follows: the solution is added at a hydrochloric acid mass fraction of 3.0%, diluted with tap water; a spray method is used; the bath temperature is 25±0.5℃; the washing tank length is 1.0m; the linear velocity is 2.0±0.1m / min; and the pressure is 1.5±0.5kg / cm². 2 ;

[0128] The S5 water washing process involves washing the printed circuit board (PCB) that has undergone the S4 hydrochloric acid washing process with deionized 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 ;

[0129] The S6 anti-diffusion process involves using the PCB via-filling resin anti-diffusion agent from the examples or comparative cases to treat the printed circuit board after the S5 water washing process. The process parameters for the anti-diffusion process are as follows: spray method, bath temperature 25±0.5℃, water washing tank length 1.0m; linear speed 2.0±0.1m / min, pressure 1.5±0.5kg / cm. 2 ;

[0130] The S7 water washing process involves washing the printed circuit board (PCB) that has undergone the S6 anti-diffusion process with deionized 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 ;

[0131] The S8 drying process is to dry the printed circuit board that has passed the S7 water washing process. The process parameters of the drying section are: drying temperature 75±5℃, drying time 1±0.2min.

[0132] The S9 resin plugging process is to plug the printed circuit board that has passed the S8 drying process. The process parameters of the resin plugging process are as follows: the plugging equipment is a vacuum plugging machine of model DSV-800 produced by Suzhou Shengfeng, and the resin used is from Shenzhen Banming Technology Co., Ltd., model BTH-8000PHP-LV, with a viscosity of 320mPa•s after thawing.

[0133] The S10 baking process involves baking the printed circuit board that has undergone the S9 resin plugging process. The process parameters for the baking process are: baking at 140°C for 60 minutes, then heating to 160°C for 30 minutes, and then removing it and letting it stand at room temperature.

[0134] The PCBs of the above embodiments or comparative examples, after being treated with the through-hole sealing resin anti-diffusion process, were subjected to the following performance tests. The specific test methods are as follows:

[0135] Contact angle test: The contact angle between the copper surface of the printed circuit board and the resin after the S10 anti-diffusion process is measured using a contact angle meter. The method is to use a syringe to drip the thawed resin onto the copper surface. The larger the contact angle, the more the anti-diffusion agent reduces the surface energy of the copper surface, and the better the anti-diffusion effect of the resin on the copper surface.

[0136] Average diffusion amount test: After the S10 baking process, the printed circuit board is cut at the hole-filling area to make a slice. The hole-filling effect is observed through an optical microscope, the amount of resin diffusion to both sides is measured, and the average value is calculated. The smaller the average diffusion amount, the better the anti-diffusion effect of the resin on the copper surface.

[0137] Reliability test: The printed circuit board after the S10 baking process is placed in the solder bath, heated to 288 ℃ for 10 s, and then cooled to room temperature. This cycle is repeated 5 times. Then, the plugged hole is cut into a slice to observe whether the resin separates from the hole wall. If it does not separate, it indicates good reliability.

[0138] The test results are shown in Table 1 below:

[0139] Table 1 Performance Test Results

[0140]

[0141] Note: " / " indicates that the resin in adjacent wells is connected together and cannot be measured, indicating severe diffusion.

[0142] Example 1: The contact angle of the resin on the copper surface after the anti-diffusion process is as follows: Figure 1 As shown; Comparative Example 16, the contact angle of the resin on the copper surface after the anti-diffusion process is as follows: Figure 2 As shown; the optical microscope examination results of the section at the plugging location in Example 1 are as follows. Figure 3 As shown; the optical microscopic examination results of the sections at the plug positions in Comparative Example 16 are as follows. Figure 4 As shown.

[0143] As shown by the experimental data in Examples 1-5 of Table 1, the PCB via-filling resin anti-diffusion agent of the present invention is applicable to the via-filling resin anti-diffusion process and can effectively solve the technical problem of easy diffusion of low-viscosity resin. After treatment with the anti-diffusion agent described in the embodiments of the present invention, the contact angle of the resin on the copper surface is greater than 80.65°, and the average diffusion amount of the resin on the copper surface is less than 135.0 μm. Reliability testing verified that the resin is tightly bonded to the via wall, and no via wall separation phenomenon occurred, which can meet the application requirements of low-viscosity via-filling resin process.

[0144] The difference between Comparative Examples 1-5 and Example 1 lies in the absence of a single component from the primary anti-diffusion agent, synergistic film-forming agent, surface energy modifier, adhesion promoter, and co-solvent in the PCB via-filling resin anti-diffusion agent system. Table 1 shows that the primary anti-diffusion agent, synergistic film-forming agent, and surface energy modifier significantly affect the contact angle and average diffusion amount of the system. These components synergistically form a low-surface-tension hydrophobic resin film; the absence of any one component leads to a decrease in anti-diffusion effect. Simultaneously, the primary anti-diffusion agent and adhesion promoter have a significant impact on process reliability; the absence of either component causes resin separation from the via wall. The co-solvent ensures the complete dissolution of hydrophobic components in the system; the absence of this component degrades the overall formulation system performance. From the perspective of the overall formulation system, the absence of any single component adversely affects the anti-diffusion effect, indicating a synergistic effect among the five components; the absence of any one component leads to a reduction in product performance.

[0145] The difference between Comparative Examples 6-10 and Example 1 is that the concentrations of the main anti-diffusion agent, synergistic film-forming agent, surface energy modifier, adhesion promoter, and co-solvent in the PCB via-filling resin anti-diffusion agent exceed the upper limit of the concentration range defined in this invention. The test results shown in Table 1 indicate that, compared to Example 1, the excessive addition of each component did not significantly enhance or weaken the anti-diffusion performance, demonstrating that within the concentration range defined in this invention, the anti-diffusion agent already possesses highly efficient resin anti-diffusion performance. While excessively increasing the component concentration does not affect the anti-diffusion effect, it leads to an unnecessary increase in reagent costs. Therefore, the components of the PCB via-filling resin anti-diffusion agent of this invention do not need to be used at excessively high concentrations; excellent via-filling resin anti-diffusion performance can be ensured within the concentration range defined in this invention.

[0146] The difference between Comparative Examples 11-15 and Example 1 is that the main anti-diffusion agent, synergistic film-forming agent, surface energy modifier, adhesion promoter, and co-solvent were replaced with other compounds of equal mass concentration and similar structure or function. The test results shown in Table 1 indicate that using corresponding functional components with different branched structures or functional group types significantly and adversely affects the anti-diffusion performance of the resin, making it difficult to achieve the technical effect required by the pore-sealing resin process of this invention.

[0147] Comparative Example 16 uses an anti-diffusion agent disclosed in the prior art (see Chinese Patent Application CN120018406A). The test results shown in Table 1 indicate that, compared to this comparative example, the PCB via-filling resin anti-diffusion agent provided by this invention has superior resin anti-diffusion performance and can better meet the process requirements of via-filling resin.

[0148] In summary, the PCB via-filling resin anti-diffusion agent and its application method provided by this invention contain effective components such as a main anti-diffusion agent, a synergistic film-forming agent, a surface energy modifier, an adhesion promoter, and a co-solvent. It can effectively solve the problem of easy diffusion of low-viscosity resin, inhibit the diffusion behavior of via-filling resin on the copper surface, and has excellent process reliability, which can significantly improve the yield of via-filling resin process. It is suitable for PCB via-filling resin pretreatment process.

[0149] 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 jack resin antipenetrant characterized by, Includes the following components by weight percentage: Main anti-diffusion agent 2.0%-4.0%; synergistic film-forming agent 1.0%-2.0%; surface energy modifier 0.5%-1.0%; adhesion promoter 1.0%-2.0%; co-solvent 2.0%-6.0%; The primary anti-diffusion agent is selected from one or more of tris(vinyldimethylsiloxy)methylsilane, vinyltris(trimethylsiloxy)silane, and vinyltris(2-methoxyethoxy)silane; The synergistic film-forming agent is selected from one or more of bis(3-mercaptopropionic acid) ethylene glycol, 3-methoxybutylmercaptoacetate, and isooctyl 3-mercaptopropionic acid; The surface energy modifier is selected from one or more of 3-fluorocatechol, 3-bromocatechol, and 3-chlorocatechol; The adhesion promoter is selected from one or more of the following: heteroazo bicyclic phosphate, (R)-spirocyclodiphenol phosphate, and 1-O-hexadecyl-sn-glycerol-2,3-cyclic phosphate. The co-solvent is selected from one or more of 2-ethynylcyclopentanol, 1-ethynylcyclopentanol, and 1-ethynyl-1-cyclohexanol.

2. The PCB via-sealing resin anti-diffusion agent according to claim 1, characterized in that, It is composed of the following components by weight percentage: main anti-diffusion agent 2.0%-4.0%; synergistic film-forming agent 1.0%-2.0%; surface energy modifier 0.5%-1.0%; adhesion promoter 1.0%-2.0%; co-solvent 2.0%-6.0%; balance is water.

3. The PCB via-sealing resin anti-diffusion agent according to claim 1, characterized in that, It consists of the following components by weight percentage: main anti-diffusion agent 3.0%; synergistic film-forming agent 1.5%; surface energy modifier 0.7%; adhesion promoter 1.5%; co-solvent 4.0%; balance is water.

4. The PCB via-sealing resin anti-diffusion agent according to claim 1, characterized in that, It consists of the following components by weight percentage: tris(vinyldimethylsiloxy)methylsilane 3.0%; bis(3-mercaptopropionic acid) ethylene glycol 1.5%; 3-fluorocatechol 0.7%; heteroazobiscyclic phosphate 1.5%; 2-ethynylcyclopentanol 4.0%; balance being water.

5. The method for preparing the PCB via-filling resin anti-diffusion agent according to any one of claims 1-4, characterized in that, Includes the following steps: The main anti-diffusion agent, synergistic film-forming agent, surface energy modifier, adhesion promoter and co-solvent are added to deionized water and mixed evenly to obtain the PCB hole-sealing resin anti-diffusion agent.

6. The application method of the PCB via-filling resin anti-diffusion agent as described in any one of claims 1-4, characterized in that, In the anti-diffusion process, the PCB via-filling resin anti-diffusion agent is used as a spraying liquid, and the PCB via-filling resin anti-diffusion agent is sprayed onto the PCB before the resin via-filling process.

7. The application method according to claim 6, characterized in that, The spray pressure is 1.5 ± 0.5 kg / cm 2 The spray time is 30 ± 5 seconds.

8. The application method according to claim 7, characterized in that, The temperature of the spray liquid is 25±0.5℃.

9. The application method according to claim 6, characterized in that, Before the anti-proliferation process, a hydrochloric acid washing process and a water washing process are also included in sequence.

10. The application method according to claim 6, characterized in that, After the anti-diffusion process and before the resin plugging process, a water washing process and a drying process are also included in sequence.

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