PCB (Printed Circuit Board) degumming and neutralizing device based on PTH (Plating Through Hole) production line and process thereof

Abstract

The invention provides a PCB glue removing and neutralizing device based on a PTH production line. The PCB glue removing and neutralizing device comprises a glue removing cylinder, a first washing cylinder, a pre-neutralizing cylinder, a second washing cylinder and a neutralizing cylinder which are sequentially arranged in the board feeding direction. The PCB glue removing and neutralizing device based on the PTH production line further comprises a liquid preparing assembly, the liquid preparing assembly comprises a liquid preparing cylinder, a stirring piece, a liquid conveying pipeline and a first switch valve, the liquid preparing cylinder is arranged close to the glue removing cylinder, the stirring piece is arranged at an opening of the liquid preparing cylinder, the stirring end of the stirring piece extends into the liquid preparing cylinder, and the liquid conveying pipeline is arranged on the liquid preparing cylinder. One end of the liquid conveying pipeline is communicated with the liquid outlet end of the liquid preparation cylinder, the other end of the liquid conveying pipeline is communicated with the liquid inlet end of the glue removing cylinder, and the first switch valve is arranged on the liquid conveying pipeline.

Description

Technical Field

[0001] The present disclosure relates to the field of printed circuit board (PCB) processing and production, and particularly to a debonding and neutralizing device and process for PCB boards based on a PTH production line. Background Art

[0002] The electroless copper plating of a PCB is usually also called immersion copper or PTH (Plating Through Hole), which is a self-catalytic redox reaction for the purpose of hole metallization to achieve conduction between layers. The process flow of PTH: swelling → debonding → pre-neutralization → neutralization → degreasing → micro-etching → pre-impregnation → activation → acceleration → electroless copper.

[0003] Currently, the chemical solution in the debonding tank of the PTH line is directly prepared in the tank, that is, an alkaline solvent, water, and potassium permanganate particles are directly added to the debonding tank, which also results in some suspended dot-like potassium permanganate particles in the debonding tank, causing the dot-like potassium permanganate to adhere to the board surface. To save water resources, the water washing tank after debonding, the water washing tank before the pre-neutralization tank, and the water washing tank before the neutralization tank are interconnected through pipelines. However, the chemical solutions in the pre-neutralization tank and the neutralization tank contain acidic solvents, resulting in the water in the water washing tank after debonding containing acidic solvents. When a PCB board with dot-like potassium permanganate adhering to its surface enters the water washing tank after debonding, the dot-like potassium permanganate will react violently with the acid therein. The specific reactions are as follows:

[0004] 2MnO4 - +2H + →Mn2O7+H2O;

[0005] Mn2O7→2MnO2+3 / 2O2;

[0006] O2+4Cu→2Cu2O;

[0007] 2Cu2O+O2→4CuO;

[0008] CuO+2H + →Cu 2+ +H2O;

[0009] The copper surface of the PCB board will be quickly corroded, resulting in local dot-like missing or perforation of the bottom copper of the PCB board. After the etching and tin stripping operation of the PCB board, the copper surface at the corroded part of the bottom copper shows concave dots, thereby increasing the line resistance of the PCB board and decreasing its electrical conductivity. Summary of the Invention

[0010] An object of the present disclosure is to overcome the deficiencies in the prior art and provide a debonding and neutralizing device and process for PCB boards based on a PTH production line that reduce the occurrence of concave dots on the bottom copper surface of the PCB board.

[0011] The object of the present disclosure is achieved by the following technical solutions:

[0012] A degumming and neutralizing device for PCB boards based on a PTH production line, comprising a degumming tank, a first water washing tank, a pre-neutralizing tank, a second water washing tank and a neutralizing tank arranged in sequence along the board feeding direction;

[0013] The degumming and neutralizing device for PCB boards based on the PTH production line further comprises a liquid preparation assembly, which includes a liquid preparation tank, a stirring member, a liquid delivery pipeline and a first switching valve. The liquid preparation tank is arranged adjacent to the degumming tank. The stirring member is arranged at the opening of the liquid preparation tank, and the stirring end of the stirring member extends into the liquid preparation tank. One end of the liquid delivery pipeline is communicated with the liquid outlet end of the liquid preparation tank, the other end of the liquid delivery pipeline is communicated with the liquid inlet end of the degumming tank, and the first switching valve is arranged on the liquid delivery pipeline.

[0014] In one embodiment, the liquid preparation assembly further comprises a liquid extraction pump, and the liquid extraction pump is arranged on the liquid delivery pipeline.

[0015] In one embodiment, the liquid preparation assembly further comprises a filter element filter, and the filter element filter is arranged on the liquid delivery pipeline.

[0016] In one embodiment, the degumming and neutralizing device for PCB boards based on the PTH production line further comprises a third water washing tank, and the third water washing tank is arranged adjacent to the neutralizing tank.

[0017] In one embodiment, the degumming and neutralizing device for PCB boards based on the PTH production line further comprises a board transfer assembly, which includes a ceiling track, an electrically driven moving block, a lifting member and a hanging basket member. The ceiling track is installed on the ceiling in the factory area of the PTH production line. The electrically driven moving block is slidably connected with the ceiling track. The lifting member is installed on the electrically driven moving block, and the hanging basket member is fixed on the lifting and moving end of the lifting member.

[0018] In one embodiment, the degumming and neutralizing device for PCB boards based on the PTH production line further comprises an overflow assembly, which includes an overflow main pipeline, a first overflow branch pipeline, a second overflow branch pipeline, a third overflow branch pipeline and a second switching valve. The overflow main pipeline is respectively communicated with one end of the first overflow branch pipeline, one end of the second overflow branch pipeline and one end of the third overflow branch pipeline. The other end of the first overflow branch pipeline is communicated with the first water washing tank. The other end of the second overflow branch pipeline is communicated with the second water washing tank. The other end of the third overflow branch pipeline is communicated with the third water washing tank. The second switching valve is arranged on the first overflow branch pipeline.

[0019] In one embodiment, the overflow assembly further includes a first overflow discharge pipe and a third on-off valve. The first overflow discharge pipe is communicated with the main overflow pipe, and the third on-off valve is arranged on the first overflow discharge pipe.

[0020] In one embodiment, the PCB degumming and neutralizing device based on the PTH production line further includes a particle real-time monitoring assembly. The particle real-time monitoring assembly is arranged in the liquid preparation tank, and the particle real-time monitoring assembly is communicatively connected with the first on-off valve.

[0021] In one embodiment, the particle real-time monitoring assembly includes an ultrasonic generating module and an ultrasonic sensor. Both the ultrasonic generating module and the ultrasonic sensor are arranged on the peripheral side wall in the liquid preparation tank, and the ultrasonic sensor is communicatively connected with the ultrasonic generating module and the first on-off valve respectively.

[0022] A PCB degumming and neutralizing process based on the PTH production line adopts the PCB degumming and neutralizing device based on the PTH production line described in any one of the above embodiments;

[0023] The PCB degumming and neutralizing process includes the following steps:

[0024] Add potassium permanganate, sodium hydroxide and water into the liquid preparation tank for stirring and dissolving to obtain an alkaline potassium permanganate solution;

[0025] Transfer the alkaline potassium permanganate solution in the liquid preparation tank through an infusion pipeline so that the alkaline potassium permanganate solution is transferred into the degumming tank;

[0026] Immerse the PCB board in the degumming tank for degumming treatment;

[0027] Immerse the degummed PCB board in the first water washing tank for the first water washing treatment;

[0028] Immerse the PCB board after the first water washing treatment in the pre-neutralization tank for pre-neutralization treatment;

[0029] Immerse the PCB board after the pre-neutralization treatment in the second water washing tank for the second water washing treatment;

[0030] Immerse the PCB board after the second water washing treatment in the neutralization tank for neutralization treatment.

[0031] Compared with the prior art, the present disclosure has at least the following advantages:

[0032] 1. By adding potassium permanganate, sodium hydroxide, and water into the liquid preparation tank, driving the stirring member to stir until the potassium permanganate is fully dissolved, and opening the first switching valve, the alkaline potassium permanganate solution in the liquid preparation tank is transported through the infusion pipeline into the degumming tank. In this way, the appearance of punctate potassium permanganate particles can be reduced, thereby reducing the occurrence of concave points on the bottom copper surface of the PCB board, and further ensuring that the PCB board has good electrical conductivity and improving the yield rate of the PCB board.

[0033] 2. By adopting the first water washing tank with independent water supply, that is, the water inlet assembly supplies water to the first water washing tank separately, so that the first water washing tank does not contain acidic solvents. As a result, the PCB board after degumming will not have the situation of solvent corroding the copper surface when entering the first water washing tank, thereby reducing the occurrence of concave points on the bottom copper surface of the PCB board, ensuring that the PCB board has good electrical conductivity, and further improving the yield rate of the PCB board.

[0034] 3. Even if there are residual tiny potassium permanganate particles in the degumming tank and adhering to the surface of the PCB board, the adhering tiny potassium permanganate particles will dissolve in the first water washing tank after being soaked and washed in the first water washing tank, so that the surface of the PCB board will not be adhered with potassium permanganate particles, ensuring that there will be no situation of the chemical solution corroding the copper surface in the pre-neutralization tank and the neutralization tank, thereby ensuring that the PCB board has good electrical conductivity and further improving the yield rate of the PCB board. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show some embodiments of the present disclosure, so they should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0036] Figure 1 It is a schematic structural diagram of a PCB board degumming and neutralizing device based on a PTH production line in an embodiment;

[0037] Figure 2 is Figure 1 a schematic structural diagram of another perspective of the PCB board degumming and neutralizing device based on the PTH production line shown;

[0038] Figure 3 It is a flowchart of a PCB board degumming and neutralizing process based on a PTH production line in an embodiment;

[0039] Figure 4 It is a microsection diagram of a PCB board produced after using the PCB board degumming and neutralizing device based on the present disclosure;

[0040] Figure 5It is a sectional view of a PCB board produced by a traditional PTH production line;

[0041] Figure 6 It is a physical diagram of a degumming and neutralizing device for PCB boards based on a PTH production line. Specific embodiments

[0042] To facilitate the understanding of the present disclosure, the present disclosure will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present disclosure are shown in the drawings. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the disclosure of the present disclosure can be understood more thoroughly and comprehensively.

[0043] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this disclosure belongs. The terms used herein in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0045] The present disclosure provides a degumming and neutralizing device for PCB boards based on a PTH production line, which includes a degumming tank, a first water washing tank, a pre-neutralizing tank, a second water washing tank and a neutralizing tank arranged in sequence along the board feeding direction. The degumming and neutralizing device for PCB boards based on a PTH production line further includes a liquid preparation assembly, the liquid preparation assembly includes a liquid preparation tank, a stirring member, a liquid delivery pipeline and a first switching valve. The liquid preparation tank is arranged adjacent to the degumming tank. The stirring member is arranged at the opening of the liquid preparation tank, and the stirring end of the stirring member extends into the liquid preparation tank. One end of the liquid delivery pipeline is communicated with the liquid outlet end of the liquid preparation tank, the other end of the liquid delivery pipeline is communicated with the liquid inlet end of the degumming tank, and the first switching valve is arranged on the liquid delivery pipeline.

[0046] Please refer to Figure 1 and Figure 2 , for a better understanding of the degumming and neutralizing device 10 for PCB boards based on a PTH production line of the present disclosure, the following further explanatory description is made on the degumming and neutralizing device 10 for PCB boards based on a PTH production line:

[0047] The debonding and neutralizing device 10 for PCB boards based on a PTH production line in one embodiment includes a debonding tank 100, a first water washing tank 200, a pre-neutralizing tank 300, a second water washing tank 400, and a neutralizing tank 500 arranged in sequence along the board feeding direction. The debonding and neutralizing device 10 for PCB boards based on the PTH production line further includes a liquid preparation assembly 600. The liquid preparation assembly 600 includes a liquid preparation tank 610, a stirring member 620, a liquid delivery pipeline 630, and a first switching valve 640. The liquid preparation tank 610 is arranged adjacent to the debonding tank 100. The stirring member 620 is arranged at the opening of the liquid preparation tank 610. The stirring end of the stirring member 620 extends into the liquid preparation tank 610. One end of the liquid delivery pipeline 630 is communicated with the liquid outlet end of the liquid preparation tank 610, and the other end of the liquid delivery pipeline 630 is communicated with the liquid inlet end of the debonding tank 100. The first switching valve 640 is arranged on the liquid delivery pipeline 630.

[0048] In this embodiment, by adding potassium permanganate, sodium hydroxide, and water into the liquid preparation tank 610, driving the stirring member 620 to stir until the potassium permanganate is fully dissolved, and opening the first switching valve 640, the alkaline potassium permanganate solution in the liquid preparation tank 610 is transported into the debonding tank 100 through the liquid delivery pipeline 630. In this way, the appearance of punctate potassium permanganate particles can be reduced, thereby reducing the appearance of concave points on the bottom copper surface of the PCB board, and further ensuring that the PCB board has good electrical conductivity and improving the yield rate of the PCB board.

[0049] Furthermore, by adopting the first water washing tank 200 with independent water supply, that is, the water inlet assembly supplies water to the first water washing tank 200 alone, so that the first water washing tank 200 does not contain acidic solvents. As a result, the PCB board after debonding will not have the situation of solvent corroding the copper surface after entering the first water washing tank 200, thereby reducing the appearance of concave points on the bottom copper surface of the PCB board, ensuring that the PCB board has good electrical conductivity, and further improving the yield rate of the PCB board.

[0050] Furthermore, even if there are residual tiny potassium permanganate particles in the debonding tank 100 and adhering to the surface of the PCB board, the adhering tiny potassium permanganate particles will dissolve in the first water washing tank 200 after being soaked and washed in the first water washing tank 200, so that the surface of the PCB board will not be adhered with potassium permanganate particles, ensuring that there will be no situation of the liquid medicine corroding the copper surface in the pre-neutralizing tank 300 and the neutralizing tank 500, thereby ensuring that the PCB board has good electrical conductivity and further improving the yield rate of the PCB board.

[0051] As shown in the figure, in one embodiment, the liquid dispensing assembly 600 further includes a liquid pumping pump 650, and the liquid pumping pump 650 is disposed on the infusion pipeline 630. It can be understood that by providing the liquid pumping pump 650 on the infusion pipeline 630, the alkaline potassium permanganate solution can be efficiently transferred from the liquid preparation cylinder 610 to the degumming cylinder 100.

[0052] As Figure 2 shown, in one embodiment, the liquid dispensing assembly 600 further includes a filter cartridge filter 660, and the filter cartridge filter 660 is disposed on the infusion pipeline 630. It can be understood that by providing the filter cartridge filter 660, the undissolved potassium permanganate particles with a particle size between 0.1 and 100 μm can be intercepted, so as to avoid the presence of suspended dot-like potassium permanganate with fine particles in the degumming process, thereby avoiding the situation that the PCB board surface is attached with dot-like potassium permanganate, and further ensuring that the PCB board has good electrical conductivity and improving the yield rate of the PCB board. Further, since the intercepted potassium permanganate has a particle size between 0.1 and 100 μm, when the alkaline potassium permanganate solution transfers towards the filter element of the filter cartridge filter 660 under the suction of the liquid pumping pump 650, the potassium permanganate particles in the filter element will be dissolved, avoiding the situation of filter element blockage and fully dissolving the potassium permanganate particles.

[0053] As Figure 1 shown, in one embodiment, the PCB board degumming and neutralizing device 10 based on the PTH production line further includes a third water washing cylinder 700, and the third water washing cylinder 700 is disposed adjacent to the neutralizing cylinder 500. It can be understood that after the PCB board is soaked and treated in the neutralizing cylinder 500, it is necessary to remove the residual neutralizing agent on the PCB board. By soaking the neutralized PCB board in the third water washing cylinder 700, the situation that the PCB board remains with sulfuric acid and is brought into the next process is avoided.

[0054] As Figure 1 and Figure 2 shown, in one embodiment, the PCB board degumming and neutralizing device 10 based on the PTH production line further includes a board transfer assembly 800. The board transfer assembly 800 includes a ceiling track 810, an electric drive moving block 820, a lifting member and a hanging basket member. The ceiling track 810 is installed on the ceiling in the PTH production line factory area. The electric drive moving block 820 is slidably connected to the ceiling track 810. The lifting member is installed on the electric drive moving block 820. The hanging basket member is fixed on the lifting mobile end of the lifting member. It can be understood that by driving the electric drive moving block 820 to move on the ceiling track 810, the hanging basket member can be moved to the corresponding cylinder, and by driving the lifting member to perform lifting operations, the hanging basket member can be immersed in the corresponding cylinder, and the hanging basket member can load PCB boards in batches to match the batch production of PCB boards.

[0055] As Figure 1 shown, in one embodiment, the degumming and neutralizing device 10 for PCB boards based on the PTH production line further includes an overflow assembly 900. The overflow assembly 900 includes an overflow main pipeline 910, a first overflow branch pipeline 920, a second overflow branch pipeline 930, a third overflow branch pipeline 940, and a second switching valve 950. One end of the overflow main pipeline 910 is respectively communicated with one end of the first overflow branch pipeline 920, one end of the second overflow branch pipeline 930, and one end of the third overflow branch pipeline 940. The other end of the first overflow branch pipeline 920 is communicated with the first water washing tank 200. The other end of the second overflow branch pipeline 930 is communicated with the second water washing tank 400. The other end of the third overflow branch pipeline 940 is communicated with the third water washing tank 700. The second switching valve 950 is arranged on the first overflow branch pipeline 920. It can be understood that the first water washing tank 200 corresponds to the water washing tank after degumming, the second water washing tank 400 corresponds to the water washing tank after pre-neutralization, and the third water washing tank 700 corresponds to the water washing tank after neutralization. And water is continuously added to the water washing tank for the water washing operation. To prevent the water in the second water washing tank 400 and the third water washing tank 700 from overflowing into the first water washing tank 200, the second switching valve 950 is arranged on the first overflow branch pipeline 920. In this way, it can be ensured that the first water washing tank 200 does not contain acidic solvent, further avoiding the situation of the chemical solution corroding the copper surface, ensuring that the PCB board has good electrical conductivity, and improving the yield rate of the PCB board. Further, to avoid wasting water resources, when the first water washing tank 200 is full, the second switching valve 950 can be opened, so that the water in the first water washing tank 200 overflows to the second water washing tank 400 and the third water washing tank 700 through the overflow main pipeline 910, the second overflow branch pipeline 930, and the third overflow branch pipeline 940. At this time, neither the second water washing tank 400 nor the third water washing tank 700 is full. Further, when either the second water washing tank 400 or the third water washing tank 700 is full, the second switching valve 950 is always in the closed state, ensuring that the water containing acidic solvent will not overflow into the first water washing tank 200, thereby ensuring that the PCB board will not have the situation of the chemical solution corroding the copper surface, and further ensuring that the PCB board has good electrical conductivity and improving the yield rate of the PCB board.

[0056] As Figure 1As shown, in one embodiment, the overflow assembly 900 further includes a first overflow discharge pipe 960 and a third switching valve 970. The first overflow discharge pipe 960 is communicated with the main overflow pipe 910, and the third switching valve 970 is arranged on the first overflow discharge pipe 960. It can be understood that when the second water washing tank 400 and the third water washing tank 700 are both full, the third switching valve 970 is opened to enable the overflow water to be uniformly recovered and treated through the first overflow discharge pipe 960.

[0057] Furthermore, in one embodiment, the overflow assembly 900 further includes a second overflow discharge pipe 980 and a fourth switching valve 990. The second overflow discharge pipe 980 is communicated with the degumming tank 100, and the fourth switching valve 990 is arranged on the second overflow discharge pipe 980. It can be understood that when the first water washing tank 200, the second water washing tank 400 and the third water washing tank 700 are all full, the fourth switching valve 990 can be opened to enable the water overflowing from the first water washing tank 200 to be uniformly recovered and treated through the second overflow discharge pipe 980, avoiding the situation that the water in the second water washing tank 400 and the third water washing tank 700 overflows into the first water washing tank 200 and ensuring that the water in the first water washing tank 200 does not contain acidic solvent.

[0058] As Figure 2 shown, in one embodiment, the PCB degumming and neutralizing device 10 based on the PTH production line further includes a particle real-time monitoring assembly 1000. The particle real-time monitoring assembly 1000 is arranged in the liquid preparation tank 610, and the particle real-time monitoring assembly 1000 is communicatively connected with the first switching valve 640. It can be understood that the particle situation in the liquid preparation tank 610 is monitored in real time through the particle real-time monitoring assembly 1000 to ensure the full dissolution of potassium permanganate and avoid the situation that there are dot-like potassium permanganate particles suspended in the alkaline potassium permanganate solution. Specifically, when the potassium permanganate particles in the liquid preparation tank 610 are fully dissolved, the particle real-time monitoring assembly 1000 feeds back a signal indicating no particles and transmits it to the first switching valve 640. After receiving the signal, the first switching valve 640 is in an open state, so that the alkaline potassium permanganate solution in the liquid preparation tank 610 can be transferred to the degumming tank 100.

[0059] As Figure 2As shown, in one of the embodiments, the particle real-time monitoring component 1000 includes an ultrasonic generating module 1010 and an ultrasonic sensor 1020. Both the ultrasonic generating module 1010 and the ultrasonic sensor 1020 are disposed on the peripheral side wall within the liquid dispensing cylinder 610. The ultrasonic sensor 1020 is communicatively connected to the ultrasonic generating module 1010 and the first switching valve 640 respectively. It can be understood that since the alkaline potassium permanganate solution is purple, it is impossible to directly observe with the naked eye whether there are undissolved particles. In this embodiment, the ultrasonic generating module 1010 generates high-frequency ultrasonic waves, and the high-frequency ultrasonic waves shuttle through the alkaline potassium permanganate solution within the liquid dispensing cylinder 610. If there are potassium permanganate particles present, the acoustic wave frequency will attenuate. The ultrasonic sensor 1020 receives the high-frequency ultrasonic waves and determines whether there are potassium permanganate particles based on the degree of attenuation of the acoustic wave frequency. In this way, it is possible to accurately determine whether the potassium permanganate particles within the liquid dispensing cylinder 610 are fully dissolved, so as to ensure that there are no potassium permanganate particles doped in the alkaline potassium permanganate solution, thereby avoiding the situation where dot-like potassium permanganate particles adhere to the surface of the PCB board when it is immersed in the degumming cylinder 100, and further ensuring that the PCB board has good electrical conductivity and improving the yield rate of the PCB board.

[0060] It should be noted that since the dissolution of particles will cause changes in the concentration, viscosity, and temperature of the liquid, but during the preparation process of the alkaline potassium permanganate solution, the viscosity and temperature when the particles are completely dissolved are basically the same as those when there are dot-like potassium permanganate particles that are not dissolved. It is difficult to monitor in real time whether the potassium permanganate particles are completely dissolved by observing the changes in viscosity and temperature. Moreover, there will be a theoretical deviation value in the solution preparation in industrial production. Even if there are dot-like potassium permanganate particles, the concentration change is not obvious, that is, within the error range of the theoretical deviation value, that is, it is difficult to monitor in real time whether the potassium permanganate is completely dissolved by the concentration. Based on this, through multiple experimental efforts, the present invention discovers that by monitoring the change in acoustic wave attenuation in real time to determine whether there are undissolved particles in the alkaline potassium permanganate solution, the change in acoustic wave attenuation is relatively obvious, and it can accurately determine whether there are undissolved particles in the potassium permanganate solution. After the ultrasonic generating module and the ultrasonic sensor are adopted in the present disclosure, there are no dot-like potassium permanganate in the alkaline potassium permanganate solution within the degumming cylinder, and thus the section of the PCB board is prepared. Figure 4 , compared with the section of the PCB board obtained by the traditional process Figure 5 , there are no pits on the bottom copper of the PCB board.

[0061] Further, the ultrasonic sensor 1020 is also communicatively connected to the liquid extraction pump 650 and the stirring member 620 respectively. When the ultrasonic sensor 1020 determines that there are no potassium permanganate particles in the liquid preparation cylinder 610, it transmits infusion signals to the first switching valve 640, the liquid extraction pump 650 and the stirring member 620 respectively, starts the first switching valve 640 and the liquid extraction pump 650, and closes the stirring member 620 at the same time, so that the alkaline potassium permanganate solution in the liquid preparation cylinder 610 is transferred to the degumming cylinder 100 through the infusion pipeline 630.

[0062] Further, the sound wave frequency of the ultrasonic generation module 1010 is 1 - 10 MHz. It can be understood that potassium permanganate particles with a particle size of 0.1 - 10 μm can be monitored at this sound wave frequency. When the particle size of potassium permanganate is greater than 10 μm, the sound wave frequency directly completely attenuates, and when the particle size of potassium permanganate is less than 0.1 μm, it can be fully dissolved under the suction force of the liquid extraction pump 650. Therefore, the particle size of potassium permanganate less than 0.1 μm can be ignored. In this way, the situation where potassium permanganate particles are doped in the alkaline potassium permanganate solution can be effectively avoided, achieving the effect of precise preparation in the liquid preparation cylinder 610, effectively improving the situation of concave bottom copper points on the PCB board surface in the PTH production line, improving the electrical conductivity of the PCB board, and thus improving the yield rate of the PCB board.

[0063] It can be understood that since the sound wave attenuation coefficient mainly depends on the particle attenuation coefficient and the medium attenuation coefficient, and the medium attenuation coefficient is the alkaline potassium permanganate solution, that is, the sound wave attenuation coefficient is mainly determined by the particle attenuation coefficient. The specific relationship formula of the sound wave attenuation coefficient is as follows:

[0064] α = α 颗粒 +α 介质 ;

[0065] Among them, α 介质 at the sound wave frequency of 1 MHz is 0.01 dB / cm, and α 介质 at the sound wave frequency of 10 MHz is 0.1 dB / cm. Therefore, at 1 - 10 MHz, α 介质 is 0.01 dB / cm - 0.1 dB / cm;

[0066] The calculation formula of the attenuation coefficient is as follows:

[0067]

[0068] Among them, L is the distance that the sound wave propagates (unit: cm), that is, the distance between the ultrasonic generation module and the ultrasonic sensor, I0 is the initial sound wave intensity, and I is the sound wave intensity after propagating the distance L;

[0069] And the particle attenuation coefficient α is related to the particle volume fraction C, the particle size d, and the sound wave frequency f. The specific relationship formula is as follows:

[0070] α 颗粒 ∝C*f n *d m ;

[0071] wherein, n is from 1 to 2, m is from 3 to 4, the particle volume fraction C is from 0 to 1%, and the particle size d is from 0.1 to 10 μm;

[0072] It can be seen from the above relationship that the particle attenuation coefficient is directly proportional to the particle volume fraction, particle size, and acoustic wave frequency. According to the Epstein-Carhart-Allegra-Hawley (ECAH) theory or scattering model, for potassium permanganate particles with a size of 0.1 μm, the particle attenuation coefficient α 0.1 has a value of 0.01 dB / cm to 0.1 dB / cm. For potassium permanganate particles with a size of 10 μm, the particle attenuation coefficient α 10 has a value of 1 dB / cm to 10 dB / cm. Therefore, under the conditions of a particle volume fraction of 0 to 1%, a particle size of 0.1 to 10 μm, and an acoustic wave frequency of 1 to 10 MHz, the attenuation degree value of high-frequency ultrasonic waves is 0.01 dB / cm to 10 dB / cm. That is to say, when the attenuation degree of the acoustic wave frequency received by the ultrasonic sensor 1020 is less than 0.01 dB / cm, it is determined that there are no particles, and the infusion process can be carried out. When the attenuation degree of the acoustic wave frequency of the ultrasonic sensor 1020 is greater than or equal to 0.01 dB / cm, it is determined that there are particles, and the stirring member 620 continuously operates, so as to improve the measurement accuracy of the ultrasonic sensor 1020 and ensure the full dissolution of potassium permanganate.

[0073] It should be noted that when the particle volume fraction is greater than 1%, the acoustic wave is completely attenuated, that is, the particle scattering situation is serious. Through this relationship, it is possible to prevent the occurrence of point-like potassium permanganate particles with a size between 0.1 and 10 μm from adhering to the surface of the PCB board, realize precise preparation in the dispensing cylinder 610, make potassium permanganate fully dissolve, and further improve the yield rate of the PCB board.

[0074] It should be additionally noted that dB / cm represents the amount of energy attenuation per centimeter of distance when the acoustic wave propagates in a medium. For example, 0.01 dB / cm means that the energy loss is about 0.23% of the original when the acoustic wave propagates 1 cm, and 10 dB / cm means that the energy loss is about 90% of the original when the acoustic wave propagates 1 cm.

[0075] Please refer to Figure 3 , this disclosure also provides a PCB board degumming and neutralizing process based on a PTH production line, using the PCB board degumming and neutralizing device based on a PTH production line described in any one of the above embodiments;

[0076] The degumming and neutralization process of the PCB board in one embodiment includes the following steps:

[0077] S100, adding potassium permanganate, sodium hydroxide and water into a liquid preparation tank for stirring and dissolving treatment to obtain an alkaline potassium permanganate solution.

[0078] In this embodiment, by mixing potassium permanganate, sodium hydroxide and water in the liquid preparation tank and fully dissolving the potassium permanganate particles under the action of a stirring member to form an alkaline potassium permanganate solution, it is avoided that there are dot-like potassium permanganate particles doped in the alkaline potassium permanganate solution, thereby avoiding the situation of the copper surface being corroded by the liquid medicine in the subsequent process, and further improving the situation of the bottom copper of the PCB board in the PTH production line and improving the conductivity of the PCB board.

[0079] Furthermore, since the alkaline potassium permanganate solution is purple and it is difficult to observe with the naked eye whether the potassium permanganate particles in the liquid preparation tank are completely dissolved. In this embodiment, while adding potassium permanganate, sodium hydroxide and water into the liquid preparation tank for stirring and dissolving treatment, the particles in the liquid preparation tank are monitored in real time through a particle real-time monitoring component, overcoming the difficulty of observing whether the particles are fully dissolved in the alkaline potassium permanganate solution, ensuring that the potassium permanganate particles are completely dissolved before transfer treatment, thereby avoiding the situation that there are dot-like potassium permanganate particles doped in the alkaline potassium permanganate solution, and further preventing the situation of the copper surface being corroded by the liquid medicine during the production process of the PCB board, avoiding the situation that the bottom copper of the PCB board is concave, and improving the conductivity and yield rate of the PCB board.

[0080] Furthermore, the specific operation steps for the particle real-time monitoring component to monitor the particles in the liquid preparation tank in real time are as follows:

[0081] Set the preset value of the attenuation degree of the ultrasonic sensor and the preset value of the sound wave frequency of the ultrasonic generating module;

[0082] Generate high-frequency ultrasonic waves with the preset sound wave frequency in the liquid preparation tank through the ultrasonic generating module to obtain the initial value of the sound wave intensity at the same time;

[0083] Receive the high-frequency ultrasonic waves in the liquid preparation tank through the ultrasonic sensor to obtain the final value of the sound wave intensity and calculate the actual value of the sound wave particle attenuation degree;

[0084] Judge and process the actual value of the sound wave frequency attenuation degree through the ultrasonic sensor. The specific judgment is as follows:

[0085] If the actual value of the sound wave particle attenuation degree is less than the preset value of the attenuation degree of the ultrasonic sensor, the ultrasonic sensor triggers an infusion signal;

[0086] If the actual value of the sound wave particle attenuation degree is greater than or equal to the preset value of the attenuation degree of the ultrasonic sensor, the ultrasonic sensor triggers a stirring signal.

[0087] It should be noted that since the positions of the ultrasonic wave generating module and the ultrasonic sensor are fixed, that is, the acoustic wave propagation distance L is a constant, the actual value of the acoustic wave particle attenuation degree can be calculated by obtaining the initial value and the final value of the acoustic wave intensity, that is, the actual value of the acoustic wave frequency attenuation degree minus α 介质 , and the preset attenuation degree is 0.01 dB / cm. By calculating the actual value of the acoustic wave particle attenuation degree in real time, it is determined whether there are potassium permanganate particles with a particle size greater than or equal to 0.1 μm in the liquid distribution cylinder. In this way, it can be ensured that the alkaline potassium permanganate solution does not contain punctate potassium permanganate particles, thereby avoiding the situation where the bottom copper surface of the PCB board is attached with punctate potassium permanganate after the degumming treatment, and further avoiding the situation where the bottom copper surface of the PCB board is concave punctate, improving the conductivity and the yield rate of the PCB board.

[0088] It should be added that when the ultrasonic sensor triggers the infusion signal, the stirring member stops outputting, the first switching valve and the liquid extraction pump are opened, and the suction force of the liquid extraction pump transfers the alkaline potassium permanganate solution in the liquid distribution cylinder to the degumming cylinder through the infusion pipeline. When the ultrasonic sensor triggers the stirring signal, the stirring member continuously outputs, and the first switching valve and the liquid extraction pump are in the closed state.

[0089] Furthermore, the preset acoustic wave frequency is 1 - 10 MHz.

[0090] Furthermore, since the value of α 介质 will change with the change of the acoustic wave frequency, in order to improve the measurement accuracy of the actual value of the acoustic wave particle attenuation degree, and each acoustic wave frequency corresponds to an acoustic wave intensity value, it is necessary to establish a database in which α 介质 , the acoustic wave frequency and the acoustic wave intensity value are in one-to-one correspondence. Also, because the ultrasonic wave generating module is communicatively connected to the ultrasonic sensor, by setting the database in the program of the ultrasonic sensor, when the ultrasonic wave generating module emits high-frequency ultrasonic waves, the ultrasonic sensor synchronously receives the actual value of the preset acoustic wave frequency, so that the ultrasonic sensor can quickly mobilize the initial value of the acoustic wave intensity and α 介质 corresponding to the actual value of the preset acoustic wave frequency through the database when calculating the actual value of the acoustic wave particle attenuation degree. In this way, the actual value of the acoustic wave particle attenuation degree can be quickly calculated, the signal response speed of the ultrasonic sensor can be improved to match the usage requirements of real-time particle monitoring, thereby ensuring that the alkaline potassium permanganate solution transferred from the liquid distribution cylinder does not contain potassium permanganate particles with a particle size greater than or equal to 0.1 μm, so that the PCB board will not be attached with punctate potassium permanganate when immersed in the degumming cylinder, to avoid the situation of the copper surface of the PCB board being corroded by the chemical solution in the subsequent process, and further ensuring that the PCB board has good conductivity and further improving the yield rate of the PCB board.

[0091] S200. Transfer the alkaline potassium permanganate solution in the liquid preparation cylinder through an infusion pipeline, so that the alkaline potassium permanganate solution is transferred into the degumming cylinder.

[0092] In this embodiment, open the first switching valve and the liquid extraction pump. The suction force of the liquid extraction pump transfers the alkaline potassium permanganate solution in the liquid preparation cylinder to the degumming cylinder through the infusion pipeline.

[0093] Further, when transferring the alkaline potassium permanganate solution in the liquid preparation cylinder through the infusion pipeline, simultaneously filter the alkaline potassium permanganate solution in the infusion pipeline through a filter element filter to filter out the potassium permanganate in the form of tiny particles with a small particle size doped in the alkaline potassium permanganate solution, ensuring that there are no potassium permanganate particles in the form of dots doped in the alkaline potassium permanganate solution. In this way, it is ensured that there are no suspended potassium permanganate particles in the form of dots in the degumming cylinder, thereby avoiding the occurrence of concave points on the bottom copper surface of the PCB board, and further ensuring that the PCB board has good electrical conductivity and improving the yield rate of the PCB board.

[0094] Further, the filtration accuracy of the filter element filter is 0.1 - 100 μm. It can be understood that potassium permanganate particles with a particle size less than 0.1 μm are in full contact and collision with the alkaline potassium permanganate solution under the action of the suction force of the liquid extraction pump, causing the potassium permanganate particles to dissolve. Therefore, potassium permanganate with a particle size less than 0.1 μm can be ignored and will dissolve during the transfer process, thus ensuring that there are no potassium permanganate particles in the form of dots in the alkaline potassium permanganate solution.

[0095] S300. Immerse the PCB board in the degumming cylinder for degumming treatment.

[0096] In this embodiment, the PCB board in the hanging basket part is immersed in the degumming cylinder through the plate transfer assembly, and then the residual gum residues on the PCB board after drilling are removed by the alkaline potassium permanganate solution, ensuring the cleanliness of the PCB board surface. At the same time, the alkaline potassium permanganate solution will etch the board surface to form a micro-rough surface, improving the palladium adsorption effect of the bottom copper, thereby improving the copper deposition effect and further improving the electrical conductivity of the PCB board.

[0097] S400. Immerse the PCB board after degumming treatment in the first water washing cylinder for the first water washing treatment.

[0098] In this embodiment, the PCB board in the hanging basket part is immersed in the first water washing cylinder through the plate transfer assembly. Then, by immersing the PCB board after degumming treatment in the first water washing cylinder, the first water washing cylinder with separate water supply is used to remove the residual alkaline potassium permanganate solution on the PCB board surface. Moreover, the first water washing cylinder does not contain acidic solvents, which can effectively avoid the situation of the copper surface being corroded by the chemical solution, thereby avoiding the occurrence of concave points on the bottom copper surface of the PCB board, improving the electrical conductivity of the PCB board, and further effectively improving the yield rate of the PCB board.

[0099] S500, immerse the PCB board after the first water washing treatment in a pre-neutralization tank for pre-neutralization treatment.

[0100] In this embodiment, the PCB board in the hanging basket part is immersed in the pre-neutralization tank through the plate transfer assembly. The solvent in the pre-neutralization tank contains sulfuric acid, which neutralizes the residual alkaline potassium permanganate solution on the surface of the PCB board, adjusts the pH value of the PCB board, and reduces the activity of the potassium permanganate solution, thereby effectively removing most of the residual alkaline potassium permanganate solvent on the surface of the PCB board.

[0101] S600, immerse the PCB board after the pre-neutralization treatment in the second water washing tank for the second water washing treatment.

[0102] In this embodiment, the PCB board in the hanging basket part is immersed in the second water washing tank through the plate transfer assembly to remove the residual pre-neutralization liquid on the surface of the PCB board.

[0103] S700, immerse the PCB board after the second water washing treatment in a neutralization tank for neutralization treatment.

[0104] In this embodiment, the PCB board in the hanging basket part is immersed in the neutralization tank through the plate transfer assembly. The liquid medicine in the neutralization tank also contains sulfuric acid, which can further remove the remaining alkaline potassium permanganate solution on the surface of the PCB board to facilitate the next process.

[0105] In one of the embodiments, after step S700, the de-gluing and neutralization process of the PCB board further includes step S800, immersing the PCB board after the neutralization treatment in the third water washing tank for the third water washing treatment. It can be understood that the PCB board in the hanging basket part is immersed in the third water washing tank through the plate transfer assembly to remove the residual neutralization liquid on the surface of the PCB board to facilitate the next process.

[0106] Compared with the prior art, the present disclosure has at least the following advantages:

[0107] 1. By adding potassium permanganate, sodium hydroxide and water to the liquid preparation tank, driving the stirring part to stir until the potassium permanganate is fully dissolved, and opening the first switching valve, the alkaline potassium permanganate solution in the liquid preparation tank is transported to the de-gluing tank through the infusion pipeline, so that the appearance of dot-like potassium permanganate particles can be reduced, thereby reducing the appearance of concave points on the bottom copper surface of the PCB board, and further ensuring that the PCB board has good electrical conductivity and improving the yield rate of the PCB board.

[0108] 2. By adopting the first water washing tank with independent water supply, that is, the water inlet assembly supplies water to the first water washing tank separately, so that the first water washing tank does not contain acidic solvent. Thus, after the degummed PCB board enters the first water washing tank, there will be no situation where the copper surface is corroded by the solvent, and further, the occurrence of concave points on the bottom copper surface of the PCB board is reduced, ensuring that the PCB board has good electrical conductivity and further improving the yield rate of the PCB board.

[0109] 3. Even if there are residual tiny potassium permanganate particles in the degumming tank and adhering to the surface of the PCB board, the adhering tiny potassium permanganate particles will dissolve in the first water washing tank after soaking and washing in the first water washing tank, so that the surface of the PCB board will not be adhered with potassium permanganate particles, ensuring that there will be no situation where the copper surface is corroded by the chemical solution in the pre-neutralization tank and the neutralization tank. Thus, it ensures that the PCB board has good electrical conductivity and further improves the yield rate of the PCB board.

[0110] The following are examples. It should be noted that the following examples do not exhaust all possible situations, and the materials used in the following examples can be obtained from commercial channels without special instructions.

[0111] The above-described embodiments only represent several implementation manners of the present disclosure, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the disclosed patent. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present disclosure, several modifications and improvements can still be made, and these all belong to the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure patent shall be subject to the appended claims.

Claims

1. A PCB board degumming and neutralization device based on a PTH production line, comprising a degumming tank, a first water washing tank, a pre-neutralization tank, a second water washing tank and a neutralization tank sequentially arranged along the board feeding direction, characterized in that: Also includes: A liquid preparation component, the liquid preparation component includes a liquid preparation cylinder, a stirring member, a liquid infusion pipeline and a first switch valve, the liquid preparation cylinder is arranged adjacent to the glue removal cylinder, the stirring member is arranged at the opening of the liquid preparation cylinder, the stirring end of the stirring member extends into the liquid preparation cylinder, one end of the liquid infusion pipeline is connected to the liquid outlet end of the liquid preparation cylinder, the other end of the liquid infusion pipeline is connected to the liquid inlet end of the glue removal cylinder, and the first switch valve is arranged on the liquid infusion pipeline.

2. The PCB board degumming and neutralization device based on the PTH production line according to claim 1 is characterized in that: The liquid preparation component also includes a liquid pump, and the liquid pump is arranged on the infusion pipeline.

3. The PCB board degumming and neutralization device based on the PTH production line according to claim 1, characterized in that: The liquid preparation component also includes a filter element filter, and the filter element filter is arranged on the infusion pipeline.

4. The PCB board degumming and neutralization device based on the PTH production line according to claim 1, characterized in that: It also includes a third water washing tank, which is arranged adjacent to the neutralization tank.

5. The PCB board degumming and neutralization device based on the PTH production line according to claim 1, characterized in that: It also includes a moving plate assembly, which includes a ceiling track, an electric drive moving block, a lifting component and a hanging basket component. The ceiling track is installed on the ceiling in the PTH production line factory area, the electric drive moving block is slidably connected to the ceiling track, the lifting component is installed on the electric drive moving block, and the hanging basket component is fixed on the lifting and moving end of the lifting component.

6. The PCB board degumming and neutralization device based on the PTH production line according to claim 4, characterized in that: It also includes an overflow component, which includes an overflow main pipe, a first overflow branch pipe, a second overflow branch pipe, a third overflow branch pipe and a second switch valve. The overflow main pipe is connected to one end of the first overflow branch pipe, one end of the second overflow branch pipe and one end of the third overflow branch pipe respectively. The other end of the first overflow branch pipe is connected to the first water washing tank, the other end of the second overflow branch pipe is connected to the second water washing tank, and the other end of the third overflow branch pipe is connected to the third water washing tank. The second switch valve is arranged on the first overflow branch pipe.

7. The PCB board degumming and neutralization device based on the PTH production line according to claim 6, characterized in that: The overflow assembly further includes a first overflow discharge pipe and a third switch valve. The first overflow discharge pipe is communicated with the overflow main pipe, and the third switch valve is arranged on the first overflow discharge pipe.

8. The PCB board degumming and neutralization device based on the PTH production line according to claim 1, characterized in that: It also includes a real-time particle monitoring component, which is arranged in the liquid preparation cylinder and is communicatively connected with the first switch valve.

9. The PCB board degumming and neutralization device based on the PTH production line according to claim 8, characterized in that: The real-time particle monitoring component includes an ultrasonic generating module and an ultrasonic sensor. The ultrasonic generating module and the ultrasonic sensor are both arranged on the peripheral side wall of the liquid dispensing cylinder. The ultrasonic sensor is communicatively connected to the ultrasonic generating module and the first switch valve respectively.

10. A PCB board degumming and neutralization process based on a PTH production line, characterized in that: A PCB board degumming and neutralization device based on a PTH production line according to any one of claims 1 to 9; The PCB board degumming and neutralization process comprises the following steps: Add potassium permanganate, sodium hydroxide and water into a liquid preparation tank for stirring and dissolving to obtain an alkaline potassium permanganate solution; The alkaline potassium permanganate solution in the liquid preparation tank is transferred through a liquid infusion pipeline so as to transfer the alkaline potassium permanganate solution to the glue removal tank; Immersing the PCB board in the degumming tank for degumming; Immersing the PCB after the degumming treatment in a first water washing tank for a first water washing treatment; Immersing the PCB board after the first water washing treatment in a pre-neutralization tank for pre-neutralization treatment; Immersing the pre-neutralized PCB in the second water washing tank for a second water washing treatment; The PCB board after the second water washing treatment is immersed in a neutralization tank for neutralization treatment.

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