Circuit boards with tangential hole structure and pad structure and circuit board processing method

Abstract

This invention discloses a circuit board with a tangential hole structure and a pad structure, and a method for processing the circuit board. The circuit board body has a solder resist gap between the hole structure and the pad structure; a solder resist layer formed by hot air is disposed on the solder resist gap. The solder resist gap between the hole structure and the pad structure provides the necessary space for the formation of the solder resist layer. By disposing of a solder resist layer formed by hot air on the solder resist gap, the solder resist ink can reduce viscosity and achieve sufficient leveling under heating conditions during the forming process, and the solvent can be controlled to evaporate and quickly set under the action of hot air. This results in a continuous, dense, and firmly adhered solder resist layer within the narrow solder resist gap. This improves production efficiency while avoiding solder resist collapse or pad contamination caused by insufficient leveling or delayed curing of the solder resist ink, reducing the risk of solder resist thinning, breakage, or copper exposure, and ensuring the structural integrity of the narrow solder resist layer and production efficiency.

Description

Technical Field

[0001] This invention relates to the field of circuit board processing technology, and in particular to a circuit board with a tangent hole structure and a pad structure, and a circuit board processing method thereof. Background Technology

[0002] Circuit boards are the basic carriers in electronic products used to realize the electrical connection and mechanical support of electronic components. By forming conductive lines, pads, and hole structures on an insulating substrate, they enable various electronic components to operate stably according to predetermined circuit relationships. As electronic products develop towards high density, miniaturization, and multi-functionality, the arrangement of conductive lines, pads, and hole structures on circuit boards is becoming increasingly compact, and the structural complexity and processing precision requirements of circuit boards are also constantly increasing.

[0003] In conventional circuit boards, hole structures typically include through-holes, blind vias, or buried vias, used to achieve interlayer electrical connections or to mount and fix component leads; pad structures are used for component soldering to ensure the reliability of electrical connections. To prevent solder diffusion and short circuits during soldering and to improve the environmental resistance of the circuit board, a solder resist layer is usually applied to the surface of the circuit board, exposing the pads while the remaining areas are covered by solder resist ink. In traditional design and manufacturing processes, to ensure the quality of the solder resist layer formation, sufficient solder resist spacing is generally reserved between the hole structures and the pad structures, allowing the solder resist ink to adhere stably during the forming process and form a continuous solder resist layer.

[0004] However, in high-density wiring or circuit board designs with special functional requirements, the hole structure and pad structure inevitably appear tangentially or at near-perfect proximity. In this configuration, only a narrow solder mask gap can be formed between the hole structure and the pad structure. For circuit boards with such tangential holes and pads, existing technologies typically face the following problems during solder mask forming: On the one hand, to prevent the solder mask ink in the narrow gap from being blown away, thinned, or even broken during forming, it is usually necessary to reduce the airflow or extend the natural leveling time. However, this approach can easily lead to insufficient curing of the solder mask ink and excessive edge fluidity, which in turn can cause solder mask layer collapse, pad contamination, or unstable solder mask coverage in the via area. On the other hand, to improve the curing efficiency and production efficiency of the solder mask ink, conventional processes often use strong airflow or fast curing conditions for solder mask forming. However, in the narrow area where the hole structure and pad structure are tangential, the airflow exerts a significant shearing effect on the incompletely cured solder mask ink, which can easily cause the solder mask layer to become thinner, break, or expose copper in this gap, thereby reducing the soldering reliability and long-term stability of the circuit board.

[0005] Therefore, when the existing circuit board processing technology faces the situation where the hole structure and the pad structure are tangential, the solder mask layer generally has the problem of not being able to balance the molding stability and curing efficiency, and cannot simultaneously ensure the structural integrity and production efficiency of the narrow solder mask layer. Summary of the Invention

[0006] The purpose of this invention is to provide a circuit board with a tangent hole structure and a solder pad structure, and a circuit board processing method, to solve the technical problem that the existing circuit board processing technology is unable to simultaneously ensure the structural integrity of the narrow solder mask layer and production efficiency.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] A circuit board with a tangent hole structure and a pad structure includes a circuit board body. The circuit board body is provided with a plurality of tangent structures, each tangent structure including a hole structure and a pad structure. The hole structure and the pad structure are tangent to each other, and a solder resist gap is left between the hole structure and the pad structure on the circuit board body. A solder resist layer formed by hot air is provided on the solder resist gap.

[0009] Optionally, the solder mask gap extends along a first direction, and the tangential structure includes a plurality of hole structures disposed on one side of the solder pad structure, with the plurality of hole structures spaced apart along the first direction.

[0010] Optionally, multiple hole structures share a common horizontal copper plating portion, and the solder mask gap is formed by the copper plating portion and the pad structure.

[0011] Optionally, the circuit board body has a blocking pad on one side of the solder resist gap, the blocking pad not contacting the hole structure and the pad structure; the solder resist ink in the solder resist gap has a flow direction to fill the solder resist gap, the blocking pad is located downstream of the solder resist gap along the flow direction, and the hot air has at least a part of a wind direction parallel to the flow direction.

[0012] Optionally, the tangential structure includes a hole structure disposed on one side of the pad structure, with a copper plating portion horizontally deposited on the outer side of the hole structure, and the solder mask gap is formed by the copper plating portion and the pad structure.

[0013] Optionally, the outer contour of the copper plating portion is circular or rectangular.

[0014] Optionally, the solder resist gap extends along a first direction, and the width of the solder resist gap remains unchanged along the first direction.

[0015] Optionally, the solder mask gap extends along a first direction and includes a middle section and an opening section. The middle section coincides with the hole structure along a second direction, and the opening section communicates with the middle section. The width of the opening section decreases along the direction closer to the middle section until the width of the opening section is equal to the width of the middle section.

[0016] Optionally, the circuit board body is provided with multiple sets of tangent structures, and the solder mask gaps of the multiple sets of tangent structures are all extended along the first direction.

[0017] A circuit board processing method for processing a circuit board with a tangent hole structure and a pad structure as described above, comprising:

[0018] A laminated circuit board body is provided, the circuit board body having several sets of tangential structures, the tangential structures including hole structures and pad structures, the hole structures and the pad structures being tangentially arranged, and the circuit board body having a solder mask gap between the hole structures and the pad structures.

[0019] Solder resist ink is applied to the circuit board body, and hot air is blown along the coating direction during the process of applying solder resist ink to the solder resist gaps.

[0020] Optionally, during the process of blowing hot air along the coating direction, a hot air source is provided, the hot air source being located above the solder resist gap, and the hot air source obliquely delivering hot air to the solder resist gap.

[0021] Optionally, during the process of blowing hot air along the coating direction, at least two hot air sources are provided; one hot air source is located on one side of the solder resist gap along the coating direction, and the other hot air source is located on the other side of the solder resist gap along the coating direction. The two hot air sources are arranged at an angle above the solder resist gap, and the point where the hot air from the two hot air sources merges coincides with the solder resist gap.

[0022] Optionally, during the process of blowing hot air along the coating direction, a hot air source is provided, which moves along the flow of solder resist ink along the solder resist gap.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention, by setting a set of tangentially arranged hole and pad structures on the circuit board body, enables the circuit board to meet the design requirement of near-perfect proximity between hole positions and pads under high-density wiring conditions, ensuring functional integration in terms of structure. Simultaneously, a solder resist gap is reserved between the hole and pad structures, providing the necessary spatial basis for the formation of the solder resist layer. A solder resist layer formed by hot air is set on the solder resist gap, allowing the solder resist ink to reduce viscosity and achieve sufficient leveling under heating conditions, while also achieving controlled evaporation and rapid setting of the solvent under the action of hot air. This results in a continuous, dense, and firmly adhered solder resist layer within the narrow solder resist gap. This improves production efficiency while avoiding solder resist collapse or pad contamination caused by insufficient solder resist ink leveling or delayed curing, reducing the risk of solder resist thinning, breakage, or copper exposure between the hole and pad structures, and ensuring the structural integrity of the narrow solder resist layer and production efficiency. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0027] Figure 1 This is a schematic diagram of a first partial structure of a circuit board provided in an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of a second partial structure of a circuit board provided in an embodiment of the present invention;

[0029] Figure 3 A schematic diagram of a third partial structure of a circuit board provided in an embodiment of the present invention;

[0030] Figure 4 A schematic diagram of the fourth partial structure of the circuit board provided in an embodiment of the present invention;

[0031] Figure 5 A schematic diagram of the fifth partial structure of the circuit board provided in an embodiment of the present invention;

[0032] Figure 6 A schematic diagram of the sixth partial structure of the circuit board provided in an embodiment of the present invention;

[0033] Figure 7 A schematic diagram of the seventh partial structure of the circuit board provided in an embodiment of the present invention;

[0034] Figure 8 This is a schematic diagram of the circuit board processing method provided in an embodiment of the present invention;

[0035] Illustration: 100, Circuit board body; 110, Hole structure; 120, Pad structure; 130, Solder mask gap; 131, Middle section of the gap; 132, Opening section of the gap; 140, Copper plating; 150, Blocking pad. Detailed Implementation

[0036] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0037] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.

[0038] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0039] This embodiment discloses a circuit board with a tangent hole structure 110 and a pad structure 120. The tangent hole structure 110 and the pad structure 120 refer to the hole structure 110 and the pad structure 120 being in a near-tangent state. At this time, the minimum width of the solder mask layer between the hole structure 110 and the pad structure 120 can reach 0.1mm. The circuit board with the above-mentioned tangent hole structure 110 and pad structure 120 has the advantages of high integration and small size. In this embodiment, by improving the structure and forming method of the circuit board, the structural integrity of the narrow solder mask layer and production efficiency are ensured while meeting the high integration requirements of the circuit board.

[0040] like Figure 1 As shown, the circuit board with tangent hole structure 110 and pad structure 120 provided in this embodiment includes a circuit board body 100. The circuit board body 100 is provided with a plurality of tangent structures, including hole structure 110 and pad structure 120. The hole structure 110 and the pad structure 120 are tangent to each other, and the circuit board body 100 leaves a solder mask gap 130 between the hole structure 110 and the pad structure 120. A solder mask layer formed by hot air is provided on the solder mask gap 130. The hot-air formed solder resist layer refers to the solder resist ink being uniformly applied to the surface of the circuit board body 100 through methods such as screen printing, spraying, or scraping, forming an initial filling state in the solder resist gap 130 between the hole structure 110 and the pad structure 120. Simultaneously, as the solder resist ink enters and flows along the solder resist gap 130, hot air is supplied through a hot air source such as a hot air nozzle, hot air knife, or hot air pipe. This hot air acts on the flowing solder resist ink, heating it to reduce its viscosity and maintain good fluidity, thus promoting the full spread and continuous filling of the narrow solder resist gap 130. Furthermore, the hot air can controllably blow away the surface layer of the solder resist ink, accelerating solvent evaporation and allowing the leveled solder resist ink to set in time, preventing the solder resist layer from thinning, breaking, or shifting due to excessive flow.

[0041] In summary, this embodiment, by setting a set of tangentially arranged hole structures 110 and pad structures 120 on the circuit board body 100, enables the circuit board to meet the design requirement of near-perfect proximity between hole positions and pads under high-density wiring conditions, ensuring functional integration in terms of structure. Simultaneously, a solder resist gap 130 is reserved between the hole structures 110 and the pad structures 120, providing the necessary spatial basis for the formation of the solder resist layer. The solder resist layer formed by hot air is set on the solder resist gap 130, allowing the solder resist ink to reduce viscosity and achieve sufficient leveling under heating conditions during the forming process, while also achieving controlled evaporation and rapid setting of the solvent under the action of hot air. This results in a continuous, dense, and firmly adhered solder resist layer within the narrow solder resist gap 130. This improves production efficiency while avoiding solder resist collapse or pad contamination caused by insufficient solder resist ink leveling or delayed curing, reducing the risk of solder resist thinning, breakage, or copper exposure between the hole structures 110 and the pad structures 120, and ensuring the structural integrity and production efficiency of the narrow solder resist layer.

[0042] As an optional implementation method, such as Figures 1 to 3As shown, the solder mask gap 130 extends along a first direction, and the tangential structure includes multiple hole structures 110 disposed on one side of the pad structure 120, with the multiple hole structures 110 spaced apart along the first direction. It should be noted that the hole structure 110 is a hole on the circuit board that provides conductivity or signal transmission, and its hole wall is plated with a copper layer. When the circuit board does not require horizontal copper plating for the hole structure 110, it means that the minimum distance between the hole structure 110 and the pad structure 120 will be less than 0.1 mm. In this case, when plating copper on the hole wall, an additional portion of the copper layer is deposited, making the copper layer slightly higher than the circuit board body 100 and flush with the pad structure 120, thereby directly forming the solder mask gap 130 between the hole structure 110 and the pad structure 120, further improving the integration of the circuit board structure.

[0043] Furthermore, such as Figures 1 to 3 As shown, multiple hole structures 110 share a common horizontal copper plating layer 140, and the solder mask gap 130 is formed by the copper plating layer 140 and the pad structure 120. In this embodiment, the multiple hole structures 110 share a common horizontal copper plating layer 140. The copper plating layer 140 refers to a continuous copper layer structure formed on the surface of the circuit board body 100, surrounding the outer side of the multiple hole structures 110, through copper plating or electroplating processes. The copper plating layer 140 and the pad structure 120 are located on the same plane or a substantially parallel plane, and its height matches or is substantially the same as that of the pad structure 120. In this way, the multiple hole structures 110 form an integral copper structure interface on the circuit board surface, rather than each hole structure 110 existing independently and discretely on the circuit board surface. Under this structure, the solder mask gap 130 is formed by the interval between the continuously arranged copper plating layer 140 and the pad structure 120. Since the copper plating layer 140 is a continuous or quasi-continuous copper surface structure, it provides a stable structural basis for the continuous forming of the narrow solder mask layer. Specifically, since the copper plating portion 140 and the pad structure 120 are at the same or similar height plane, during the solder resist coating and hot air forming process, the flow interface of the solder resist ink within the solder resist gap 130 is mainly defined by two parallel or nearly parallel metal boundaries. This makes the solder resist ink more uniformly stressed during flow, reducing local accumulation, shrinkage, or breakage caused by height differences or abrupt boundary changes. Especially under the action of hot air, the solder resist ink forms a stable capillary spreading state between the copper plating portion 140 and the pad structure 120, and can also quickly complete leveling and shaping under heating conditions, thereby significantly improving the continuity and density of the solder resist layer within the narrow solder resist gap 130.

[0044] Furthermore, the copper plating section 140, as a metal structure arranged parallel to the pad structure 120, has a higher thermal conductivity than the substrate of the circuit board body 100. During hot air forming, it can transfer heat more evenly, making the solder resist ink within the solder mask gap 130 heat up more uniformly. This avoids problems such as premature curing or excessive evaporation in localized areas due to excessive temperature differences, thereby further reducing the risk of thinning, breakage, or copper exposure of the solder mask layer between the hole structure 110 and the pad structure 120. Thus, without increasing the design spacing between the hole structure 110 and the pad structure 120, the structural integrity, forming consistency, and production yield of the narrow solder mask layer are effectively improved, further leveraging the structural and process advantages of highly integrated circuit boards.

[0045] Furthermore, such as Figure 1 As shown, a blocking pad 150 is provided on one side of the solder mask gap 130 on the circuit board body 100. The blocking pad 150 does not contact the hole structure 110 and the pad structure 120. The solder mask ink in the solder mask gap 130 has a flow direction to fill the solder mask gap 130. The blocking pad 150 is located downstream of the solder mask gap 130 along the flow direction, and the hot air has at least a part of a wind direction parallel to the flow direction. The blocking pad 150 can serve as an electrical signal connection point of the circuit board body 100, and also as a physical isolation device to prevent excessive flow or overflow of solder mask ink into the pad area during the forming process, effectively ensuring the integrity of the solder mask layer. At the same time, the non-contact between the blocking pad 150 and the hole structure 110 and the pad structure 120 ensures that there will be no short circuit or other poor electrical connection between the blocking pad 150 and other circuit structures, maintaining the normal operating performance of the circuit board.

[0046] Specifically, during hot air molding, the flow direction of the solder resist ink is influenced by the hot air. The hot air has at least a portion parallel to the flow direction of the solder resist ink, allowing it to directly act on the surface of the flowing ink, accelerating solvent evaporation and helping the ink to evenly fill the solder resist gap 130. This coordinated flow of hot air and solder resist ink ensures the ink flows rapidly and sets smoothly within the solder resist gap 130, preventing uneven ink flow due to uneven airflow or improper direction, which could affect the quality of the solder resist layer. By placing the blocking pad 150 downstream of the solder resist gap 130, the flow direction of the solder resist ink remains stable throughout the hot air molding process, reducing molding defects caused by excessively long or short flow paths. Furthermore, the design of the blocking pad 150 prevents the ink from being unnecessarily carried away by the hot air, ensuring the formation of a continuous and stable solder resist layer within the solder resist gap 130 during the molding process. While ensuring high integration of the circuit board, the structural integrity, molding consistency and production yield of the narrow solder mask layer are effectively improved, further leveraging the structural and process advantages of the high-integration circuit board.

[0047] As other alternative implementation methods, such as Figure 4 and Figure 5 As shown, the tangential structure includes a hole structure 110 disposed on one side of the pad structure 120. A copper plating portion 140 is horizontally deposited on the outer side of the hole structure 110. The solder mask gap 130 is formed by the copper plating portion 140 and the pad structure 120. The outer contour of the copper plating portion 140 is circular or rectangular.

[0048] Based on the above implementation methods, such as Figures 1 to 3 , Figure 5 and Figure 6 As shown, the solder resist gap 130 extends along a first direction, and the width of the solder resist gap 130 remains constant along the first direction. By designing the solder resist gap 130 to extend uniformly along the first direction while maintaining a constant width, stable flow of the solder resist ink within the gap is ensured, avoiding ink accumulation or thinning caused by uneven gap width. Furthermore, due to the uniformity of the solder resist gap 130's width, the ink evaporation and setting processes during hot air molding can occur in a stable environment, effectively improving the molding quality of the solder resist layer, avoiding problems such as insufficient local curing or uneven leveling, and enhancing the reliability and stability of the circuit board.

[0049] Based on the above implementation methods, such as Figure 4 and Figure 7 As shown, the solder mask gap 130 extends along the first direction and includes a gap middle section 131 and a gap opening section 132. The gap middle section 131 coincides with the hole structure 110 along the second direction. The gap opening section 132 communicates with the gap middle section 131. The width of the gap opening section 132 decreases along the direction close to the gap middle section 131 until the width of the gap opening section 132 is equal to the width of the gap middle section 131.

[0050] Understandably, in this embodiment, the copper plating portion 140 is designed as a rectangular structure with rounded corners. The rounded corners create a decreasing width of the gap opening segment 132, forming a funnel-like outline with the pad structure 120. This funnel-shaped solder resist gap 130, with its gradually decreasing width of the gap opening segment 132, effectively guides the solder resist ink towards the center of the gap during ink flow. This results in more uniform and stable ink flow during filling, reducing ink accumulation and loss in the outer area and preventing uneven solder resist layer thickness or flow caused by excessive ink diffusion. Simultaneously, the width of the middle segment 131 of the gap coincides with the hole structure 110 along the second direction, allowing the solder resist ink to precisely cover the area surrounding the hole structure 110 and ensuring a uniform solder resist layer in that area.

[0051] In a preferred embodiment, solder resist ink is applied to the circuit board body 100 starting from the wider gap opening section 132. The wider design of the gap opening section 132 guides the ink flow. As the ink is gradually applied to the middle section 131 of the gap, it begins to flow towards and fill the narrower gap area. During this process, the ink flow rate gradually increases, and the assistance of hot air further facilitates smoother ink flow. The hot air heats the ink at a certain temperature and speed, reducing its viscosity and enhancing its fluidity, allowing it to effectively spread and evenly fill the narrow solder resist gap 130. Finally, when the solder resist ink approaches and completely fills the solder resist gap 130, the blocking pad 150 is located downstream of the solder resist gap 130 and does not contact the hole structure 110 or the pad structure 120. Through its physical barrier function, the blocking pad 150 effectively prevents ink from spreading to unwanted areas. Especially during ink flow, the blocking pad 150 prevents ink from overflowing or entering the pad area, thus avoiding pad contamination and unnecessary ink accumulation. Simultaneously, the blocking pad 150 ensures that the ink can smoothly fill along the ideal flow path, preventing uneven distribution or overflow caused by external interference during flow, thereby guaranteeing the stability and integrity of the solder resist layer. Therefore, this embodiment, by setting a funnel-shaped solder resist gap 130 on the circuit board body 100, and combining hot air forming process and the physical guidance of the blocking pad 150, ensures precise ink flow within the solder resist gap 130, effectively preventing excessive ink flow, accumulation, and loss, while ensuring uniform filling and timely setting of the ink within the solder resist gap 130. This design optimizes the solder resist layer forming process, avoids solder resist layer defects caused by uneven ink flow or overflow, thereby improving the manufacturing quality and reliability of the circuit board, and providing an efficient and stable solution for the production of highly integrated circuit boards.

[0052] Similarly, when copper is plated on the hole wall, an additional portion of the copper layer is deposited so that the copper layer is slightly higher than the circuit board body 100 and flush with the pad structure 120, thereby directly forming a solder mask gap 130 between the hole structure 110 and the pad structure 120. The solder mask gap 130 can also be designed in a funnel shape, and in conjunction with the setting of the blocking pad 150, the integration of the circuit board and production efficiency can be improved, and the stability and integrity of the solder mask layer can be guaranteed.

[0053] Based on the above implementation, the circuit board body 100 is provided with multiple sets of tangent structures, and the solder mask gaps 130 of the multiple sets of tangent structures are all extended along the first direction. Two or more sets of tangent structures can be provided according to the design requirements of the circuit board.

[0054] Example 2:

[0055] The circuit board processing method provided in this embodiment is used to process the circuit board with tangent hole structure 110 and pad structure 120 in Embodiment 1, including:

[0056] A laminated circuit board body 100 is provided. The circuit board body 100 is provided with several sets of tangent structures. The tangent structures include hole structure 110 and pad structure 120. The hole structure 110 and pad structure 120 are tangent to each other. The circuit board body 100 leaves a solder mask gap 130 between the hole structure 110 and the pad structure 120.

[0057] Solder resist ink is applied to the circuit board body 100, and hot air is blown along the coating direction during the process of applying solder resist ink in the solder resist gap 130.

[0058] Specifically, the ink is applied by spraying. The hot air velocity is preset to 0.2~1.5m / s, and the temperature is preset to 60~90°C. Further adjustments are made according to the type of solder resist ink and the complexity of the circuit board to ensure that the solder resist layer can completely fill the solder resist gap 130. For example, when the solder resist layer is not completely filled or the ink flow is uneven, the hot air velocity and temperature can be increased. When ink overflow occurs, the hot air velocity and temperature can be decreased. If the hot air velocity and temperature cannot simultaneously ensure that the solder resist layer can completely fill the solder resist gap 130 and that the ink does not overflow after adjustment, the gap opening section 132 and the blocking pad 150 are added.

[0059] As an optional implementation, during the process of blowing hot air along the coating direction, a hot air source is provided, which is located above the solder resist gap 130, and the hot air source obliquely delivers hot air to the solder resist gap 130.

[0060] As another optional implementation, such as Figure 3 As shown, during the process of blowing hot air along the coating direction, at least two hot air sources are provided; one hot air source is located on one side of the solder resist gap 130 along the coating direction, and the other hot air source is located on the other side of the solder resist gap 130 along the coating direction. The two hot air sources are arranged at an angle above the solder resist gap 130, and the hot air from the two hot air sources merges at the same point as the solder resist gap 130.

[0061] Understandably, in this embodiment, two hot air sources are arranged at an angle, with one hot air source located on one side of the solder resist gap 130 along the coating direction and the other on the opposite side. The point where the hot air from both sources converges overlaps with the solder resist gap 130, forming a concentrated and uniform hot air field. This design, through the hot air arrangement, ensures that the ink flows uniformly and fills the solder resist gap 130 during the coating process, avoiding uneven ink flow or accumulation. The angled arrangement of the hot air sources can uniformly heat the ink, promote solvent evaporation, accelerate flow, and prevent the ink from curing too quickly or overflowing. The hot air convergence area directly acts on the ink, ensuring its uniform distribution and timely setting throughout the solder resist gap 130, thereby guaranteeing the integrity and stability of the solder resist layer. This hot air arrangement improves the uniformity and efficiency of the coating process, ensures the quality of the solder resist layer, and optimizes the production process.

[0062] It should also be pointed out that, in combination Figure 3 and Figure 8 As shown, in the area where the two hot air sources converge, there are two air components: one acts perpendicularly to the circuit board body 100, and the other is positioned along the coating direction. The perpendicular air component acts on the surface of the circuit board body 100, helping the ink to diffuse evenly and fill the narrow solder resist gap 130. This air component effectively promotes ink flow and ensures that the ink does not accumulate or over-diffuse due to uneven airflow during the coating process. The air component along the coating direction guides the ink to flow along the length of the solder resist gap 130, ensuring that the ink flows stably and evaporates promptly throughout the coating area, allowing the solder resist layer to form uniformly and stably. This effectively avoids problems such as uneven ink flow, incomplete curing, or ink accumulation, ensuring the integrity and stability of the solder resist layer on the high-density circuit board during the coating process, thereby optimizing the efficiency and quality of the entire production process.

[0063] Based on the above implementation, during the hot air blowing process along the coating direction, a hot air source is provided, which moves along the solder resist ink flow along the solder resist gap 130. Specifically, the movement of the hot air source is consistent with the ink flow direction, which can provide a uniform heating effect while the ink is flowing, thereby avoiding the phenomenon of uneven local ink cooling or drying, and ensuring that the ink can smoothly fill every corner of the solder resist gap 130. This reduces the instability of the solder resist ink flow caused by excessive evaporation and avoids the solder resist ink being excessively blown away or accumulated during the coating process. Through this setting of synchronous movement of the hot air source and the ink, not only is the efficiency of ink filling the solder resist gap 130 improved, but the uniformity and stability of the solder resist layer are also enhanced, thereby optimizing the production process and quality of high-density circuit boards.

[0064] To facilitate understanding by those skilled in the art, the circuit board fabrication method is described below:

[0065] S1. Press the etched multilayer inner board together to obtain the circuit board body 100;

[0066] S2. Drill holes in the circuit board body 100 to form a hole structure 110;

[0067] S3. Perform horizontal copper plating on the circuit board body 100 to form a copper plating part 140 and a pad structure 120.

[0068] S4. Electroplating, dry film treatment and etching treatment are performed sequentially on the circuit board body 100.

[0069] S5. Apply solder resist ink to the circuit board body 100. During the process of applying solder resist ink to the solder resist gap 130, blow hot air along the coating direction.

[0070] S6. The circuit board body 100 is cleaned, dried and packaged in sequence.

[0071] It should be understood that the above-mentioned drilling, horizontal copper plating, electroplating, dry film treatment, etching treatment, cleaning, drying and other treatments are all technical means well known to those skilled in the art, and will not be elaborated in detail in this embodiment.

[0072] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A circuit board with a tangent hole structure and a pad structure, characterized in that, The circuit board includes a circuit board body (100), on which a plurality of tangent structures are provided. The tangent structures include hole structures (110) and pad structures (120). The hole structures (110) and the pad structures (120) are tangentially arranged, and the circuit board body (100) leaves a solder mask gap (130) between the hole structures (110) and the pad structures (120). A solder mask layer formed by hot air is provided on the solder mask gap (130). The circuit board body (100) has a blocking pad (150) on one side of the solder resist gap (130). The blocking pad (150) does not contact the hole structure (110) and the pad structure (120). The solder resist ink in the solder resist gap (130) has a flow direction to fill the solder resist gap (130). The blocking pad (150) is located downstream of the solder resist gap (130) along the flow direction, and the hot air has at least a wind direction that is partially parallel to the flow direction.

2. A circuit board with a tangent hole structure and a pad structure according to claim 1, characterized in that, The solder mask gap (130) extends along a first direction, and the tangential structure includes a plurality of hole structures (110) disposed on one side of the pad structure (120), and the plurality of hole structures (110) are spaced apart along the first direction.

3. A circuit board with a tangent hole structure and a pad structure according to claim 2, characterized in that, Multiple hole structures (110) are horizontally plated with copper plating portions (140), and the solder mask gap (130) is formed by the copper plating portions (140) and the pad structures (120).

4. A circuit board with a tangent hole structure and a pad structure according to claim 1, characterized in that, The tangential structure includes a hole structure (110) disposed on one side of the pad structure (120), and a copper plating portion (140) is horizontally deposited on the outside of the hole structure (110). The solder mask gap (130) is formed by the copper plating portion (140) and the pad structure (120).

5. A circuit board with a tangent hole structure and a pad structure according to claim 4, characterized in that, The outer contour of the copper plating section (140) is circular or rectangular.

6. A circuit board with a tangent hole structure and a pad structure according to any one of claims 1-5, characterized in that, The solder resist gap (130) extends along a first direction, and the width of the solder resist gap (130) remains unchanged along the first direction.

7. A circuit board with a tangent hole structure and a pad structure according to any one of claims 1-5, characterized in that, The solder mask gap (130) extends along a first direction and includes a gap middle section (131) and a gap opening section (132). The gap middle section (131) coincides with the hole structure (110) along a second direction. The gap opening section (132) communicates with the gap middle section (131). The width of the gap opening section (132) decreases along the direction close to the gap middle section (131) until the width of the gap opening section (132) is equal to the width of the gap middle section (131).

8. A circuit board with a tangent hole structure and a pad structure according to any one of claims 1-5, characterized in that, The circuit board body (100) is provided with multiple sets of tangent structures, and the solder mask gaps (130) of the multiple sets of tangent structures are all extended along the first direction.

9. A circuit board processing method, characterized in that, For processing a circuit board with a tangent hole structure and a pad structure as described in any one of claims 1-8, comprising: A laminated circuit board body is provided, the circuit board body having several sets of tangential structures, the tangential structures including hole structures and pad structures, the hole structures and the pad structures being tangentially arranged, and the circuit board body having a solder mask gap between the hole structures and the pad structures. Solder resist ink is applied to the circuit board body, and hot air is blown along the coating direction during the process of applying solder resist ink to the solder resist gaps.

10. The circuit board processing method according to claim 9, characterized in that, During the process of blowing hot air along the coating direction, a hot air source is provided, the hot air source is located above the solder resist gap, and the hot air source obliquely delivers hot air to the solder resist gap.

11. The circuit board processing method according to claim 9, characterized in that, During the process of blowing hot air along the coating direction, at least two hot air sources are provided; one hot air source is located on one side of the solder resist gap along the coating direction, and the other hot air source is located on the other side of the solder resist gap along the coating direction. The two hot air sources are arranged at an angle above the solder resist gap, and the point where the hot air from the two hot air sources merges coincides with the solder resist gap.

12. The circuit board processing method according to claim 9, characterized in that, During the process of blowing hot air along the coating direction, a hot air source is provided, which moves along the flow of solder resist ink along the solder resist gap.

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