Printing ink hole plugging method for large-aperture blind hole and circuit board
By setting up spaced lower oil holes on the plug hole screen and scraping the plug hole ink in the direction using a scraper to make it fall into the blind hole in sequence, the plug hole ink cannot be stuffed or completely filled. Problem, improving the integrity and fullness of the plug hole.
Patent Information
- Application Number
- CN202411517596.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-29
- Publication Date
- 2025-02-18
AI Technical Summary
When the plug ink on the wire mesh is inserted into the large-size blind hole through the through holes on the aluminum sheet, it is easy to cause the plug holes to be unable to be inserted or completely filled, resulting in problems such as depression, yellowing and false leakage of plug holes. .
The plug hole mesh is adopted with a plurality of lower oil holes, and the lower oil holes are arranged at intervals. At least two lower oil holes are arranged at intervals in the first direction. The plug hole ink is scraped in the first direction through a scraper to make it pass through All lower oil holes fall into the blind holes in turn.
Through this method, the problem of ink in the plug hole in the blind hole cannot be inserted or completely filled is avoided, the integrity and fullness of the plug hole is improved, and the phenomenon of depression, yellowing and false leakage of plug holes is reduced.
Smart Images
Figure CN119485928A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of printed circuit boards, and in particular to an ink plugging method for large-diameter blind holes and a circuit board. Background Art
[0002] Large-aperture blind holes mainly refer to blind holes drilled on circuit boards by mechanical drilling machines in a controlled depth drilling manner. The aperture of such blind holes is generally greater than or equal to 0.35 mm. After drilling the blind holes, it is necessary to metalize the hole walls of the blind holes by chemical copper deposition and electroplating to obtain PTH (Plating Through Hole), thereby achieving the purpose of connecting the inner and outer layers of the circuit board. Since the blind holes have a "cup" structure, after the circuit board is surface treated, it is easy for residual medicine to remain in the holes of the blind holes. The residual medicine has the ability to oxidize / corrode copper, which will affect the conduction and signal transmission effects of the blind holes, and affect their reliability and service life. Therefore, in order to ensure the service life and reliability of the blind holes, plugging ink is generally used to seal the blind holes (plug holes).
[0003] The conventional plugging method is to use a screen with an aluminum sheet to plug the holes. That is, first, a through hole about 0.1mm larger than the overall aperture of the blind hole is drilled at the location of the hole to be plugged on the aluminum sheet, and then the plugging ink on the screen is plugged into the blind hole through the through hole on the aluminum sheet by silk screen printing and extrusion.
[0004] When the plugging ink on the silk screen is inserted into the blind hole through the through hole on the aluminum sheet, the plugging ink cannot be inserted into the blind hole or the plugging ink cannot completely fill the blind hole, which leads to the phenomenon of plugging hole depression, yellowing and false leakage when the plugging ink in the blind hole is pre-cured later. Summary of the invention
[0005] The present application provides an ink plugging method for large-aperture blind holes and a circuit board, which can improve the problem in the related art that when the plugging ink on the silk screen is plugged into the blind hole through the through hole on the aluminum sheet, the plugging ink cannot be inserted into the blind hole or the plugging ink cannot completely fill the blind hole.
[0006] In a first aspect, an embodiment of the present application provides an ink plugging method for a large-diameter blind hole, comprising:
[0007] Providing a substrate, wherein the substrate is provided with a blind hole;
[0008] Placing a plug hole screen above the substrate, wherein the plug hole screen is provided with a plug hole unit corresponding to the blind hole, wherein the plug hole unit includes a plurality of lower oil holes, the plurality of lower oil holes are arranged at intervals, and at least two of the lower oil holes are arranged at intervals in the first direction;
[0009] Place the plugging ink on the plugging stencil, and use a squeegee to scrape the plugging ink along the first direction, so that the plugging ink falls into the blind holes in sequence through all the lower ink holes.
[0010] In some embodiments, a plurality of the blind holes and a plurality of the plugging units are provided and are arranged in one-to-one correspondence.
[0011] In some embodiments, at least two of the lower ink holes are arranged at intervals in a second direction perpendicular to the first direction.
[0012] In some embodiments, the distance between two adjacent lower ink holes is 0.075 mm - 0.1 mm, and the aperture of the lower ink hole is less than or equal to 1 / 2 of the aperture of the blind hole.
[0013] In some embodiments, the orthographic projection of the lower ink hole on the side of the substrate facing the plugging stencil includes an ink feeding part and a tolerance part. The ink feeding part is located inside the orthographic projection of the blind hole on the side of the substrate facing the plugging stencil, and the tolerance part is located outside the orthographic projection of the blind hole on the side of the substrate facing the plugging stencil.
[0014] In some embodiments, the maximum distance between the edge of the orthographic projection of the blind hole on the side of the substrate facing the plugging stencil and the tolerance part is 0.05 mm - 0.15 mm.
[0015] In some embodiments, the plugging stencil includes an aluminum sheet and a wire mesh connected to the edge of the aluminum sheet, and the tension of the wire mesh is 18 N / cm 2 -26 N / cm 2 。
[0016] In some embodiments, the distance between the plugging stencil and the substrate is 6 mm - 10 mm, and the pressure of the squeegee on the plugging stencil is 5 kg / cm 2 -8 kg / cm 2 。
[0017] In some embodiments, a plurality of the lower ink holes are arranged in a "pin" shape or a "field" shape.
[0018] In a second aspect, an embodiment of the present application provides a circuit board, which is processed by the ink plugging method for large-aperture blind holes as described in the first aspect.
[0019] The ink plugging method for large-aperture blind holes provided in the embodiment of the present application has the beneficial effect that: since the plugging screen is first placed above the substrate, the plugging screen is provided with a plugging unit corresponding to the blind hole, the plugging unit includes a plurality of lower oil holes, the plurality of lower oil holes are arranged at intervals, and at least two lower oil holes are arranged at intervals in the first direction, and then plugging ink is placed on the plugging screen, and a scraper is used to scrape the plugging ink along the first direction, so that the plugging ink falls into the blind hole in turn through all the lower oil holes. Therefore, when the plugging ink falls into the blind hole through one of the lower oil holes, the air at the bottom of the blind hole can be discharged through the other lower oil holes, thereby avoiding the phenomenon that the plugging ink cannot be plugged into the blind hole or the plugging ink cannot completely fill the blind hole.
[0020] The beneficial effects of the circuit board provided in the present application compared with the prior art can be referred to the description of the beneficial effects of the ink plugging method for large-aperture blind holes provided in the present application compared with the prior art, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.
[0022] Figure 1 It is a schematic diagram of the structure of a circuit board and a screen in the related art;
[0023] Figure 2 This is a flow chart of a method for plugging a large-diameter blind hole with ink in one of the embodiments of the present application;
[0024] Figure 3 This is a schematic diagram of the structure of a substrate and a plug-hole screen in one of the embodiments of the present application;
[0025] Figure 4 yes Figure 3 A cross-sectional view of the substrate and the plug hole screen shown;
[0026] Figure 5 is Figure 3 A schematic diagram showing a plugging ink being placed on the plugging screen and a scraper being used to scrape the plugging ink in a first direction so that the plugging ink falls into the blind holes in sequence through one of the lower oil holes;
[0027] Figure 6 is Figure 3 The schematic diagram shows that plugging ink is placed on the plugging screen and a scraper is used to scrape the plugging ink along a first direction so that the plugging ink falls into the blind holes in sequence through another lower oil hole.
[0028] The meanings of the marks in the figure are:
[0029] 1. Circuit board; 2. Screen; 3. Blind hole; 4. Through hole;
[0030] 10. Substrate; 11. Blind hole; 20. Plug hole screen; 21. Oiling hole; 211. Oiling part; 212. Tolerance part; 22. Screen frame; 30. Plug hole ink; 40. Scraper. DETAILED DESCRIPTION
[0031] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.
[0032] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.
[0033] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0034] References to "one embodiment", "some embodiments" or "an embodiment" described in the specification of this application mean that a particular feature, structure or characteristic described in conjunction with the embodiment is included in one or more embodiments of the present application. Thus, the phrases "in one embodiment", "in some other embodiments", "in some other embodiments", etc., which appear at different places in this specification, do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. In addition, in one or more embodiments, particular features, structures or characteristics may be combined in any suitable manner.
[0035] In order to illustrate the technical solution of the present application, a description is given below with reference to specific drawings and embodiments.
[0036] Please refer to Figure 1 , Figure 1 It is a structural schematic diagram of a circuit board and a screen in the related technology.
[0037] The conventional plugging method is to use a screen 2 with an aluminum sheet to plug the holes, that is, first drill a through hole 4 about 0.1 mm larger than the overall aperture of the blind hole 3 at the location of the hole to be plugged on the aluminum sheet, and then use the screen printing and scraping extrusion method to plug the plugging ink on the screen 2 through the through hole 4 on the aluminum sheet into the blind hole 3.
[0038] Since the interior of the blind hole 3 is in a "water cup" structure, when the plugging ink on the silk screen is inserted into the blind hole 3 through the through hole 4 on the aluminum sheet, the plugging ink will immediately seal the through hole 4 on the aluminum sheet and the opening of the blind hole 3, and the through hole 4 on the aluminum sheet cannot be vented, resulting in the air at the bottom of the blind hole 3 cannot be discharged, resulting in the phenomenon that the plugging ink cannot be inserted into the blind hole 3 or the plugging ink cannot completely fill the blind hole 3, which in turn leads to the phenomenon that the plugging hole is sunken, yellowed, and false leak plugging occurs when the plugging ink in the blind hole 3 is pre-cured later.
[0039] Among them, plugging depression means that there are bubbles in the plugging ink inside the hole of the blind hole 3 during plugging, which are discharged after pre-curing and baking, resulting in the plugging ink at the hole mouth of the blind hole 3 being depressed; yellowing means that when the plugging ink at the hole mouth of the blind hole 3 is sunken too much, the plugging ink at the angle between the surface copper at the hole mouth of the blind hole 3 and the hole wall of the blind hole 3 is too thin, and visually becomes the color of copper; false leak plugging means that due to the presence of air in the hole of the blind hole 3, the plugging ink is not plugged into the hole during plugging, and visually there is no plugging ink in the hole of the blind hole 3, as if no plugging has been done.
[0040] In view of this, the embodiments of the present application provide an ink plugging method for large-aperture blind holes and a circuit board, wherein a plugging screen is first placed above a substrate, the plugging screen is provided with a plugging unit corresponding to the blind hole, the plugging unit includes a plurality of lower oil holes, the plurality of lower oil holes are arranged at intervals, at least two lower oil holes are arranged at intervals in a first direction, plugging ink is then placed on the plugging screen, and a scraper is used to scrape the plugging ink along the first direction, so that the plugging ink falls into the blind hole in turn through all the lower oil holes, so when the plugging ink falls into the blind hole through one of the lower oil holes, the air at the bottom of the blind hole can be discharged through other lower oil holes, thereby avoiding the phenomenon that the plugging ink cannot be plugged into the blind hole or the plugging ink cannot completely fill the blind hole.
[0041] Please refer to Figures 2 to 6 , Figure 2 This is a flow chart of a method for plugging a large-diameter blind hole 11 with a plugging ink 30 in one embodiment of the present application. Figure 3 is a schematic diagram of the structure of the substrate 10 and the plug hole screen 20 in one embodiment of the present application, Figure 4 yes Figure 3 The cross-sectional view of the substrate 10 and the plug hole screen 20 shown in FIG. Figure 5 is Figure 3A schematic diagram showing that a plugging ink 30 is placed on the plugging stencil 20 as shown, and a squeegee 40 is used to scrape the plugging ink 30 in a first direction, so that the plugging ink 30 sequentially falls into the blind holes 11 through one of the ink feeding holes 21. Figure 6 is Figure 3 A schematic diagram showing that a plugging ink 30 is placed on the plugging stencil 20 as shown, and a squeegee 40 is used to scrape the plugging ink 30 in a first direction, so that the plugging ink 30 sequentially falls into the blind holes 11 through the other ink feeding hole 21.
[0042] In a first aspect, an embodiment of the present application provides a plugging method for a plugging ink 30 of a large-aperture blind hole 11, including:
[0043] S100: Provide a substrate 10, and the substrate 10 is provided with blind holes 11.
[0044] Specifically, the substrate 10 may be a multilayer board that has been subjected to operations such as blanking, inner layer imaging, AOI (Automated Optical Inspection), lamination, drilling, electroless copper plating, panel electroplating, and outer layer circuit.
[0045] The substrate 10 may include multiple circuit layers, a conductive layer is disposed in the blind hole 11, and the conductive layer electrically conducts at least two circuit layers. In this embodiment, the aperture of the blind hole 11 is 0.45 mm.
[0046] S200: Place the plugging stencil 20 above the substrate 10. The plugging stencil 20 is provided with plugging units corresponding to the blind holes 11. The plugging units include a plurality of ink feeding holes 21, the plurality of ink feeding holes 21 are spaced apart, and at least two ink feeding holes 21 are spaced apart in the first direction.
[0047] Specifically, both the plugging units and the blind holes 11 may be provided in multiple numbers and are arranged in one-to-one correspondence. One blind hole 11 corresponds to a plurality of ink feeding holes 21, and the first direction may be Figure 5 and Figure 6 the direction indicated by the hollow arrow in. The plurality of ink feeding holes 21 may be arranged in a "Lv" shape, a "Pin" shape, or a "Tian" shape.
[0048] In this embodiment, the plugging unit includes four ink feeding holes 21 with an aperture of 0.2 mm, the four ink feeding holes 21 are arranged in a "Tian" shape, and the distance between adjacent two ink feeding holes 21 is 0.1 mm.
[0049] It should be noted that positioning holes may be provided on both the substrate 10 and the plugging stencil 20 for positioning the substrate 10 and the plugging stencil 20.
[0050] S300 : placing the plugging ink 30 on the plugging screen 20 , and using the scraper 40 to scrape the plugging ink 30 along the first direction, so that the plugging ink 30 falls into the blind holes 11 through all the oil holes 21 in sequence.
[0051] Specifically, in the first direction, the plugging ink 30 first falls into the blind hole 11 from one of the lower oil holes 21, and then falls into the blind hole 11 from other lower oil holes 21 arranged in the first direction with the current lower oil hole 21. A solder mask screen printing plugging machine can be used in combination with the plugging screen 20, and the plugging ink 30 on the plugging screen 20 can be squeezed into the corresponding blind hole 11 through the lower oil holes 21 by scraping glue and printing.
[0052] When the plugging ink 30 falls into the blind hole 11 through one of the lower oil holes 21, the air at the bottom of the blind hole 11 can be discharged through other lower oil holes 21 arranged in a first direction with respect to the current lower oil hole 21 (e.g., Figure 5 and Figure 6 The plugging screen 20 between two adjacent lower oil holes 21 can be used as a connection point to divide the plugging ink 30 into multiple strands, and the bubbles in the plugging ink 30 can be divided and discharged, thereby avoiding the phenomenon that the plugging ink 30 cannot be inserted into the blind hole 11 or the plugging ink 30 cannot completely fill the blind hole 11.
[0053] It is understandable that a small amount of air at the bottom of the blind hole 11 can also be discharged from the gap between the plug-via screen 20 and the substrate 10 .
[0054] As can be seen from the above, the method for plugging large-aperture blind holes 11 with plugging ink 30 provided in the embodiment of the present application is that the plugging screen 20 is first placed above the substrate 10, and the plugging screen 20 is provided with a plugging unit corresponding to the blind hole 11, and the plugging unit includes a plurality of lower oil holes 21, and the plurality of lower oil holes 21 are arranged at intervals, and at least two lower oil holes 21 are arranged at intervals in the first direction, and then the plugging ink 30 is placed on the plugging screen 20, and the plugging ink 30 is scraped along the first direction by a scraper 40, so that the plugging ink 30 falls into the blind hole 11 in turn through all the lower oil holes 21. Therefore, when the plugging ink 30 falls into the blind hole 11 through one of the lower oil holes 21, the air at the bottom of the blind hole 11 can be discharged through the other lower oil holes 21, thereby avoiding the phenomenon that the plugging ink 30 cannot be plugged into the blind hole 11 or the plugging ink 30 cannot completely fill the blind hole 11.
[0055] The method for plugging a large-diameter blind hole 11 with a plugging ink 30 provided in the embodiment of the present application improves the problem of voids in the plugging ink 30 in the blind hole 11 and false copper exposure caused by depression at the hole mouth.
[0056] Optionally, the plugging ink 30 is placed on the plugging stencil 20, and the plugging ink 30 is scraped along the first direction using a squeegee 40. After the plugging ink 30 sequentially falls into the blind holes 11 through all the lower ink holes 21, a photosensitive solder resist ink can be printed on the entire surface of the substrate 10, followed by pre-baking. The solder resist ink is pre-cured at a low temperature of 75 °C to facilitate exposure. Then, through the method of image transfer, the solder resist ink in the areas for other functions such as welding, testing, heat dissipation, and inserting components is developed and removed, and the solder resist image is transferred to the substrate 10, with the time controlled within ≤10 min. After production, the plugging ink 30 in the blind holes 11 and the solder resist ink are fused with each other, and visually, the plugging is full, there is no false exposure of copper at the orifice edge with redness, and there are no plugging holes or false plugging leaks.
[0057] After printing a layer of photosensitive solder resist ink on the entire surface of the substrate 10, the substrate 10 can continue to undergo processes such as character printing, surface treatment, shaping, FQC (Final Quality Control), packaging, and shipping.
[0058] Optionally, before the plugging ink 30 is placed on the plugging stencil 20 and the plugging ink 30 is scraped along the first direction using a squeegee 40 so that the plugging ink 30 sequentially falls into the blind holes 11 through all the lower ink holes 21, the oxide on the surface of the substrate 10 can be removed and the surface of the substrate 10 can be cleaned.
[0059] Optionally, at least two lower ink holes 21 are arranged at intervals in the second direction, and the second direction is perpendicular to the first direction.
[0060] With such a setting, the plugging ink 30 can simultaneously fall into the blind holes 11 through at least two lower ink holes 21 arranged at intervals in the second direction, thereby improving the plugging efficiency and being more conducive to full plugging.
[0061] Optionally, multiple lower ink holes 21 are arranged in a "pin" shape or a "field" shape.
[0062] With such a setting, when the plugging ink 30 falls into the blind hole 11 through one of the lower ink holes 21, the air at the bottom of the blind hole 11 can be discharged through other lower ink holes 21 arranged at intervals in the first direction with respect to the current lower ink hole 21, and the other lower ink holes 21 will not be filled with the plugging ink 30, which is more conducive to exhaust. Also, the plugging ink 30 can simultaneously fall into the blind holes 11 through at least two lower ink holes 21 arranged at intervals in the second direction, thereby improving the plugging efficiency and being more conducive to full plugging.
[0063] Please refer to Figure 3 and Figure 4 , in this embodiment, the distance S between two adjacent lower ink holes 21 is 0.075 mm - 0.1 mm, and the diameter d of the lower ink hole 21 is less than or equal to 1 / 2 of the diameter D of the blind hole 11.
[0064] By adopting the above scheme, it is possible to avoid the spacing between two adjacent lower oil holes 21 being too small, resulting in the lower oil holes 21 being unable to be made on the plugging screen 20, and when the scraper 40 is used to scrape the plugging ink 30 along the first direction, the plugging screen 20 between the two adjacent lower oil holes 21 has a certain supporting strength. It is also possible to avoid the spacing between two adjacent lower oil holes 21 being too large, resulting in the sum of the cross-sectional areas of all the lower oil holes 21 exceeding the cross-sectional area of the blind hole 11 by too much, thereby causing the plugging ink 30 to accumulate at the edge of the blind hole 11.
[0065] Optionally, the orthographic projection of the lower oil hole 21 on the side of the substrate 10 facing the plug hole screen 20 includes a lower oil portion 211 and a tolerance portion 212, the lower oil portion 211 is located inside the orthographic projection of the blind hole 11 on the side of the substrate 10 facing the plug hole screen 20, and the tolerance portion 212 is located outside the orthographic projection of the blind hole 11 on the side of the substrate 10 facing the plug hole screen 20.
[0066] By adopting the above solution, it is possible to avoid the plugging ink 30 being unable to fall into the blind hole 11 through the lower oil hole 21 due to the alignment error between the substrate 10 and the plugging screen 20 .
[0067] Optionally, a maximum distance C between an edge of an orthographic projection of the blind hole 11 on a side of the substrate 10 facing the plugging screen 20 and the tolerance portion 212 is 0.05 mm-0.15 mm.
[0068] Such a configuration can avoid the plugging ink 30 being unable to fall into the blind hole 11 through the lower oil hole 21 due to the alignment error between the substrate 10 and the plugging screen 20, and can also avoid the maximum distance between the edge of the orthographic projection of the blind hole 11 on the side of the substrate 10 facing the plugging screen 20 and the tolerance portion 212 being too large, resulting in the accumulation of plugging ink 30 at the edge of the blind hole 11.
[0069] Please refer to Figures 3 to 6 In this embodiment, the plug hole screen 20 includes an aluminum sheet and a wire mesh connected to the edge of the aluminum sheet, and the tension of the wire mesh is 18N / cm 2 -26N / cm 2 .
[0070] By adopting the above scheme, it is convenient to use the scraper 40 to scrape the plugging ink 30 along the first direction, so that when the plugging ink 30 falls into the blind hole 11 through all the oil holes 21 in turn, the plugging screen 20 and the plate surface of the substrate 10 form a certain angle, so that part of the air at the bottom of the blind hole 11 is discharged from the gap between the plugging screen 20 and the substrate 10, and it is also possible to avoid the screen being easily broken when cutting the screen corresponding to the aluminum sheet due to excessive tension of the screen, and the screen being insufficient in tension after cutting the screen corresponding to the aluminum sheet.
[0071] It should be noted that the lower oil hole 21 can be processed on the aluminum sheet by mechanical drilling or laser drilling according to the design requirements of the plug hole aluminum sheet. The aluminum sheet after drilling is adhered to the blank screen with adhesive. After the adhesive is cured, the plug hole unit (the position of the plug hole lower ink area) or the screen corresponding to the aluminum sheet is cut off, and then the blank area of the screen edge is sealed with a sealing slurry (to prevent ink leakage). The plug hole screen 20 can also include a screen frame 22.
[0072] For example, the screen can be a 43T blank screen with a tension of 23N / cm 2 -25N / cm 2 After bonding the aluminum sheet and cutting off the screen corresponding to the ink area, the tension is 20N / cm 2 -23 N / cm 2 .
[0073] Optionally, the distance between the plug hole screen 20 and the substrate 10 is 6 mm-10 mm, and the pressure of the scraper 40 on the plug hole screen 20 is 5 kg / cm 2 -8kg / cm 2 .
[0074] Such a configuration can avoid that the plugging ink 30 is drawn and tailed at the edge of the blind hole 11 due to insufficient distance between the plugging screen 20 and the substrate 10 (the plugging ink 30 is adhered during plugging, and after the plugging is completed, the plugging screen 20 is lifted, and the adhered plugging ink 30 will be stretched into filaments, and when the plugging is disconnected, the drawn filaments will stick to the plate surface of the substrate 10 and the mesh bottom of the plugging screen 20), and can also avoid that the plugging screen 20 and the plate surface of the substrate 10 have an angle that is too small, resulting in poor air permeability, part of the air at the bottom of the blind hole 11 cannot be discharged from the gap between the plugging screen 20 and the substrate 10, and if the distance between the plugging screen 20 and the substrate 10 is too high, it will lead to insufficient plugging pressure, resulting in poor plugging ink.
[0075] For example, a semi-automatic lifting screen printing plugging machine is used for production, the distance between the plugging screen 20 and the substrate 10 can be 8 mm, the scraper 40 is a "shovel-type" scraper, and the pressure of the scraper 40 on the plugging screen 20 can be 6.8 kg / cm 2 .
[0076] The plugging method of the large-diameter blind hole 11 using the plugging ink 30 provided in the embodiment of the present application can improve the plugging efficiency by 50% and save the cost by 50%.
[0077] In a second aspect, an embodiment of the present application provides a circuit board, which is processed by a plugging method using a plugging ink 30 for a large-diameter blind hole 11 as in the first aspect.
[0078] In the circuit board provided in the embodiment of the present application, during processing, the plugging screen 20 is first placed above the substrate 10, and the plugging screen 20 is provided with a plugging unit corresponding to the blind hole 11, and the plugging unit includes a plurality of lower oil holes 21, and the plurality of lower oil holes 21 are arranged at intervals, and at least two lower oil holes 21 are arranged at intervals in the first direction, and then the plugging ink 30 is placed on the plugging screen 20, and the plugging ink 30 is scraped along the first direction by a scraper 40, so that the plugging ink 30 falls into the blind hole 11 through all the lower oil holes 21 in sequence. Therefore, when the plugging ink 30 falls into the blind hole 11 through one of the lower oil holes 21, the air at the bottom of the blind hole 11 can be discharged through the other lower oil holes 21, thereby avoiding the phenomenon that the plugging ink 30 cannot be inserted into the blind hole 11 or the plugging ink 30 cannot completely fill the blind hole 11.
[0079] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.
Claims
1. A method for plugging large-diameter blind holes with ink, characterized in that: Including: Providing a substrate, the substrate being provided with blind vias; Placing a plugging stencil above the substrate, the plugging stencil being provided with plugging units corresponding to the blind vias, each plugging unit including a plurality of lower oil holes, the plurality of lower oil holes being spaced apart, and at least two of the lower oil holes being spaced apart in a first direction; Placing plugging ink on the plugging stencil and using a squeegee to scrape the plugging ink along the first direction, so that the plugging ink sequentially falls into the blind vias through all of the lower oil holes.
2. The ink plugging method for large-diameter blind holes according to claim 1, characterized in that: Both the blind vias and the plugging units are provided in a plurality and are provided in one-to-one correspondence.
3. The ink plugging method for large-diameter blind vias according to claim 1, characterized in that: At least two of the lower oil holes are spaced apart in a second direction, the second direction being perpendicular to the first direction.
4. The ink plugging method for large-diameter blind vias according to claim 1, characterized in that: The distance between two adjacent lower oil holes is 0.075 mm - 0.1 mm, and the aperture of the lower oil hole is less than or equal to 1 / 2 of the aperture of the blind via.
5. The ink plugging method for large-diameter blind vias according to claim 1, characterized in that: The orthographic projection of the lower oil hole on the side of the substrate facing the plugging stencil includes a lower oil part and a tolerance part, the lower oil part being located inside the orthographic projection of the blind via on the side of the substrate facing the plugging stencil, and the tolerance part being located outside the orthographic projection of the blind via on the side of the substrate facing the plugging stencil.
6. The ink plugging method for large-diameter blind vias according to claim 5, characterized in that: The maximum distance between the edge of the orthographic projection of the blind via on the side of the substrate facing the plugging stencil and the tolerance part is 0.05 mm - 0.15 mm.
7. The ink plugging method for large-diameter blind vias according to claim 1, characterized in that: The plug hole screen includes an aluminum sheet and a wire mesh connected to the edge of the aluminum sheet, and the tension of the wire mesh is 18N / cm 2 -26N / cm 2 .
8. The ink plugging method for large-diameter blind vias according to any one of claims 1 to 7, characterized in that: The distance between the plug hole screen and the substrate is 6mm-10mm, and the pressure of the scraper on the plug hole screen is 5kg / cm 2 -8kg / cm 2 .
9. The ink plugging method for large-diameter blind vias according to any one of claims 1 to 7, characterized in that: The plurality of lower oil holes are arranged in a "pin" shape or a "field" shape.
10. A circuit board, characterized in that: The circuit board is processed by the ink plugging method for large-aperture blind vias according to any one of claims 1 to 9.