Horizontal soaking and spraying combined etching processing system
By combining horizontal soaking and spray etching technology and using electrolytic oxidation regeneration reaction tanks, the problem of poor etching quality of thick copper circuit boards and easily oxidized metal resist layer circuit boards is solved, achieving efficient and environmentally friendly high-quality etching effect.
Patent Information
- Application Number
- CN202420261448.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Priority Date
- 2023-02-03
- Filing Date
- 2024-02-02
- Publication Date
- 2025-03-28
- Estimated Expiration
- 2034-02-02
AI Technical Summary
The existing etching process is difficult to meet the high-quality etching requirements of thick copper circuit boards and metal resist layer circuit boards that are easily oxidized, and traditional spray etching can easily lead to oxidation and damage of the resist layer.
An etching processing system combining horizontal immersion and spraying is used interphase through horizontal immersion etching production line and spraying etching production line, reducing the time length of spray etching, reducing the damage to the resist layer, and increasing the redox potential of the etching liquid through electrolytic oxidation regeneration reaction tank.
It effectively reduces the oxidation of silver and other metal corrosion-resistant layers that are easily oxidized, improves the etching quality of thick copper circuit boards, meets the standards of high-quality etching, and achieves the improvement of production efficiency.
Smart Images
Figure CN222691972U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of circuit board etching production, and in particular relates to an etching processing system combining horizontal immersion and spraying. Background Art
[0002] In the current production process of circuit boards, etching is an important production process. During the etching process, an anti-corrosion layer is used to protect the circuit pattern part that needs to be retained on the copper clad board, and the chemical reaction between the etching liquid and copper is used to chemically corrode and remove the unnecessary copper foil on the circuit pattern of the copper clad board, thereby obtaining the desired circuit pattern.
[0003] ⒈ Common anti-corrosion layers include polymer anti-corrosion layers and metal anti-corrosion layers. Common polymer anti-corrosion layers include ink and film, and common metal anti-corrosion layers include tin and tin alloys.
[0004] ⒉ Etching solution and copper etching agent: The solution used to etch copper foil in the etching production line is called etching working solution, or etching solution for short. The component in the etching solution that can corrode and dissolve metallic copper is called copper etching agent.
[0005] Circuit board etching solutions are divided into acidic etching solutions and alkaline etching solutions; the copper etching agents of common acidic etching solutions are mainly cupric chloride and ferric chloride, and the copper etching agents of common alkaline etching solutions are mainly cupric chloride ammonia complexes or other divalent copper ammonia complexes.
[0006] During the acid etching process, cupric chloride and / or ferric chloride react to generate cuprous chloride and / or ferrous chloride. Therefore, it is necessary to continuously add an oxidant and a replenishing liquid whose main component is hydrochloric acid to the etching production line to regenerate the copper etching agent to maintain etching production. During the alkaline etching process, the copper etching agent is oxidized and regenerated by air, and it is also necessary to continuously add a replenishing liquid whose main component is ammonia water and / or ammonium salt to maintain etching production.
[0007] The above-mentioned replenishing liquid is called etching liquid in the industry. When its raw material includes the residual liquid after copper is extracted from the etching waste liquid, it is called regenerated etching liquid. The solution that overflows from the etching production line by continuously adding etching liquid and oxidant to the acid etching production line is acidic etching waste liquid. The solution that overflows from the etching production line by continuously adding ammonia water and ammonium salt mixed replenishing liquid to the alkaline etching production line is alkaline etching waste liquid.
[0008] At present, the industry generally adopts a spray etching production line to complete etching by spraying an etching working liquid at about 50°C under pressure on the circuit board. Since the etching working liquid contacts the air over a large area during the spraying process, a large amount of oxygen is dissolved in the etching working liquid.
[0009] With the technological development of electronic communications and automotive electronic products, the industry has put forward new processing technology standards and requirements for the etching processing of metal anti-corrosion layer circuit boards and thick copper circuit boards in circuit boards. Some circuit boards use silver as the metal anti-corrosion layer, and the copper layer of thick copper circuit boards is getting thicker and thicker. When the traditional spray etching scheme is used to etch the circuit board with silver anti-corrosion layer, since silver metal is easily oxidized, the etching working liquid with temperature and a large amount of oxygen dissolved in it is sprayed onto the circuit board, which will cause the silver anti-corrosion layer to be rapidly oxidized and then react with the etching working liquid. When the traditional spray etching scheme is used to etch the thick copper circuit board, since the copper layer to be etched is thicker, the etching time is long, and a large spray pressure is required to exchange the etching working liquid between the circuits on the circuit board in time. Long-term high-pressure spraying with temperature is easy to damage the anti-corrosion layer and thus affect the etching quality. Therefore, it is difficult to achieve the etching quality standards of such special circuit products by using the existing etching operation method to etch the thick copper circuit board and the silver anti-corrosion layer circuit board, and the etching processing method needs to be improved. Utility Model Content
[0010] The utility model aims to provide an etching processing system combining horizontal immersion etching and spray etching, which uses the combination of immersion and spray etching production lines as a process improvement to improve the etching quality and meet the etching quality requirements of easily oxidized metal anti-corrosion layer circuit boards and thick copper circuit board products.
[0011] The purpose of the utility model is achieved through the following technical solutions:
[0012] A horizontal immersion and spray combined etching processing system comprises at least one section of spray etching production line, characterized in that it also comprises at least one section of horizontal immersion etching production line;
[0013] The horizontal immersion etching production line is mainly composed of an immersion etching tank / pool and a circuit board conveying mechanism, as well as a liquid jet water jet arranged in the tank / pool for exchanging the etching liquid in the tank / pool. The immersion etching tank / pool is used to contain the etching liquid, and the circuit board conveying mechanism is used to support the circuit board to be etched and advance and immerse it in the etching liquid contained in the immersion etching tank / pool. The circuit board conveying mechanism is at least partially located in the immersion etching tank / pool.
[0014] The liquid outlet of the liquid jet water jet is arranged above and / or below the circuit board conveying mechanism and / or between the components of the circuit board conveying mechanism, and the etching working liquid is drawn from the immersion etching tank / pool for spraying, or the etching working liquid is drawn from other containers loaded with etching working liquid for spraying.
[0015] The circuit board conveying mechanism is one of a reel conveying device, a roller conveying device, and a combined conveying device of reels and rollers, that is, a conveying device in which multiple roller reel branches and / or rollers are installed side by side and at least one of the roller reel branches and / or rollers is driven to rotate when started. Preferably, the conveying mechanism on the horizontal immersion etching production line adopts a roller conveying device. More preferably, the roller of the roller conveying device is an insoluble absorbent cotton roller, that is, it adopts an insoluble absorbent cotton roller combination. At present, the conventional circuit board etching conveying mechanism in the industry adopts a reel conveying device, which is a combination of multiple roller reel branches. The roller reel branches are made of multiple round hard plastic sheets (reel sheets) that are inserted on the main shaft at intervals. The combination of roller reel branches is conducive to the flow of etching working liquid on the circuit board surface when spray etching is used so that the newly sprayed etching working liquid can contact the circuit board. In the existing etching equipment, only absorbent cotton rollers are arranged at the inlet and outlet of the conveying mechanism of the etching production line to prevent the etching working liquid from flowing out from the inlet and outlet of the conveying mechanism. Since the material used for the rollers is relatively hard and they are in point contact with the circuit boards when conveying them, long-term conveyance can easily scratch the anti-corrosion layer of the circuit boards and cause quality problems.
[0016] When the transmission mechanism described in the utility model adopts an insoluble absorbent cotton roller combination, the outer layer material of the roller is a fabric or a polymer soft material that is insoluble in the etching working liquid, so it can better protect the anti-corrosion layer on the circuit board and reduce the quality problems caused by the anti-corrosion layer of the circuit board being scratched. Figure 5 Schematic diagram of an insoluble absorbent cotton roller.
[0017] The spray etching production line described in the utility model is a conventional spray etching device in the art, comprising a spray etching tank and a circuit board conveying mechanism, and a nozzle arranged near the circuit board conveying mechanism for spraying etching liquid to the circuit board conveying mechanism. The nozzle is arranged above and / or below and / or on the side of the circuit board conveying mechanism.
[0018] The utility model combines two etching processing methods, immersion and spraying, to improve the existing etching processing technology for thick copper circuit boards and circuit boards with metal anti-corrosion layers that are easily oxidized, and divides the etching operation of the circuit board into two or more sections, and alternately adopts horizontal immersion etching processing and spraying etching processing. That is, the copper that needs to be removed on the circuit board is removed by immersion etching, so as to shorten the length of the spray etching time, so as to effectively reduce the damage of the circuit board anti-corrosion layer by pressurized spraying, reduce the oxidation and dissolution of the metal anti-corrosion layer that is easily oxidized, such as silver, or avoid the problem of poor etching caused by the falling off of the polymer anti-corrosion layer or the metal anti-corrosion layer due to long-term spraying when etching thick copper plates, thereby improving the etching quality.
[0019] The horizontal immersion etching process described in the utility model has the following advantages:
[0020] (1) It can make the etching solution fully contact with the copper surface for etching reaction and improve the pool effect;
[0021] (2) Since there is no strong liquid jet, the external force impact of the liquid on the anti-corrosion layer is reduced, and the anti-corrosion layer is prevented from loosening due to long-term impact on the etching of thick copper plates, which affects the etching quality;
[0022] (3) Since the external force impact of the liquid on the circuit board anti-corrosion layer is reduced, the temperature of the etching working liquid can be increased to accelerate the etching reaction without easily damaging the anti-corrosion layer;
[0023] (4) Since the etching solution does not come into contact with the air over a large area and dissolve oxygen, the oxidation reaction on the metal anti-corrosion layer of the circuit board such as silver, which is easily oxidized, can be reduced.
[0024] As a preferred embodiment of the present invention, a spray etching production line is used to perform the final etching operation on the circuit board, which can effectively perform etching correction on the circuit pattern on the circuit board to obtain a better etching quality effect, which is equivalent to using the process advantage known as flash etching in the industry.
[0025] In order to achieve good etching quality effects for different etching objects, the utility model sets the etching liquid on the horizontal immersion etching production line and the etching liquid on the spray etching production line to have the same or different components and concentrations as well as the working temperatures of the etching liquids according to actual conditions.
[0026] The utility model can be improved as follows: a liquid suction pipe and / or a liquid suction knife is added to the horizontal immersion etching production line, that is, a liquid suction pipe and / or a liquid suction knife is added to the immersion etching tank / pool, which can be combined with the liquid spray water knife in the tank / pool to strengthen the rapid exchange of etching liquid. The improved structure is as follows Figure 4 The liquid inlet of the liquid pipette and the liquid inlet of the liquid blade are arranged above and / or below the circuit board conveying mechanism and / or between the components of the circuit board conveying mechanism.
[0027] The utility model can be improved as follows: at least one electrolytic oxidation regeneration reaction tank is added, and the electrolytic oxidation regeneration reaction tank is divided into an anode tank area and a cathode tank area by an electrolytic tank partition. The anode tank area is cyclically connected to the horizontal immersion etching production line and / or the spray etching production line through a liquid flow pipeline to electrolytically oxidize the etching working liquid on the horizontal immersion etching production line and / or the spray etching production line to regenerate the copper etching agent and return it to the etching production line.
[0028] The electrolytic anode and the electrolytic cathode are respectively arranged in the anode tank area and the cathode tank area of the electrolytic oxidation regeneration reaction tank, the electrolytic anode is connected to the positive electrode of the electrolytic power supply, and the electrolytic cathode is connected to the negative electrode of the electrolytic power supply. During the electrolysis process, the anolyte in the anode tank area is an etching working solution and circulates with the etching production line. The etching working solution on the etching production line enters the anode tank area, and the anolyte undergoes oxidation and regeneration of the copper etching agent and then flows back to the etching production line to continue the etching chemical reaction. That is, the electrolytic oxidation regeneration reaction tank is used to oxidize cuprous chloride and ferrous chloride in the acidic etching working solution to generate cupric chloride and ferric chloride copper etching agents, or to electrochemically oxidize the monovalent copper ammonia complex in the alkaline etching solution to generate a divalent copper complex copper etching agent. As a preferred embodiment, the catholyte in the cathode tank area is an etching waste liquid, and copper is electroprecipitated in the catholyte.
[0029] The electrolytic oxidation regeneration reaction tank can be connected to one or more etching production lines, and is used to electrolytically oxidize and regenerate the etching working solution on one or more etching production lines. Each electrolytic oxidation regeneration reaction tank can electrolytically oxidize and regenerate the etching working solution on one etching production line alone, or can electrolytically oxidize and regenerate the etching working solution on two etching production lines at the same time.
[0030] The electrolytic oxidation regeneration reaction tank of the utility model is used to electrochemically oxidize the etching working solution, so that the etching working solution can become a solution with a high concentration of copper etching agent, called high redox potential etching solution, and then return to the etching production line to continue etching.
[0031] When the utility model uses an acidic etching solution that does not contain iron, the main components of the etching solution are cupric chloride and hydrochloric acid, and it also contains ammonium chloride and / or sodium (potassium) chloride additives.
[0032] When the acidic etching solution contains ferric chloride, a higher redox potential value will be obtained, making the etching solution have better etching performance.
[0033] When the utility model etches the silver anti-corrosion layer circuit board, the main components of the alkaline etching solution used are ammonia water, ammonium sulfate, and tetraammine copper sulfate. [Cu(NH3)2]2SO4 is electrolytically oxidized and regenerated into Cu(NH3)4SO4 copper etching agent in an electrolytic oxidation regeneration reaction tank, which can enable the alkaline etching working solution to obtain a higher redox potential value.
[0034] The electrolytic anode of the utility model is an insoluble electrode, preferably at least one of a titanium-based coating insoluble anode, conductive graphite, and an electrode with a surface of metal platinum; more preferably, it is a titanium-based coating electrode.
[0035] The electrolytic cathode of the utility model is a conductive material, preferably conductive graphite and / or titanium plate, wherein stainless steel is preferably used when the cathode electrolyte is alkaline.
[0036] The electrolytic cell separator of the utility model is preferably at least one of an anion exchange membrane, a bipolar membrane, a reverse osmosis membrane, and a proton membrane. More preferably, when the electrolytes are all acidic, an anion exchange membrane is selected, and when the electrolytes are all alkaline, any one of a reverse osmosis membrane, a bipolar membrane, and a proton membrane is selected.
[0037] The utility model can also be improved as follows: at least one solution flow exchange tank is added; the arrangement of the solution flow exchange tank is selected from one of the following:
[0038] 1) The solution flow exchange tank is arranged at the connection between the horizontal immersion etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank, so that it is circulatedly connected with the horizontal immersion etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank through a liquid flow pipeline; or,
[0039] 2) The solution flow exchange tank is arranged at the connection between the spray etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank, so that it is circulatedly connected with the spray etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank through a liquid flow pipeline; or,
[0040] 3) The solution flow exchange tank is arranged at the connection between the horizontal immersion etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank, and at the connection between the spray etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank, so that it is respectively connected to the horizontal immersion etching production line, the spray etching production line, and the anode tank area of the electrolytic oxidation regeneration reaction tank through liquid flow pipelines for circulation.
[0041] The utility model can also be improved as follows: a temporary storage tank is added to temporarily store chemicals and process chemical reactions. The temporary storage tank is connected to at least one of the electrolytic oxidation regeneration reaction tank, the horizontal immersion etching production line, the spray etching production line, and the solution flow exchange tank through a pipeline, or is arranged on a connecting pipeline between at least two of the above.
[0042] The utility model can also be improved as follows: an overflow buffer tank is added to solve the problem of smooth flow of solution between tanks. The overflow buffer tank is connected to at least one of the electrolytic oxidation regeneration reaction tank, horizontal immersion etching production line, spray etching production line, solution flow exchange tank, and temporary storage tank through a pipeline, or is arranged on a connecting pipeline between at least two of the above.
[0043] The utility model can also be improved as follows: a hot and cold temperature exchanger is added to at least one of the electrolytic oxidation regeneration reaction tank, horizontal immersion etching production line, spray etching production line, solution flow exchange tank, temporary storage tank, and overflow buffer tank to control the working temperature of the etching solution and / or electrolyte.
[0044] The utility model can also be improved as follows: additional sensors and automatic detection and feeding controllers are provided to detect each reaction liquid in the system in real time, so that the etching process can be run according to a pre-programmed program. The sensor is placed in at least one of the following positions: ① placed in the electrolytic oxidation regeneration reaction tank, ② placed in the etching production line, ③ placed in a container connected to the electrolytic oxidation regeneration reaction tank or the etching production line; the sensor is selected from at least one of a thermometer, an acidity meter, a hydrometer, a pH meter, an oxidation-reduction potentiometer (ORP meter), a photoelectric colorimeter, a pressure gauge, a liquid level gauge, and a chlorine gas detector; the detection signal input end of the automatic detection and feeding controller is connected to the detection signal output section of the sensor, and the control signal output end of the automatic detection and feeding controller is connected to the control signal input end of at least one of the electrolytic power supply, pump, valve, hot and cold temperature exchanger, and etching production line in the system.
[0045] The utility model can also be improved as follows: because the etching liquid used in the horizontal immersion etching production line and the etching liquid used in the spray etching production line have different components, concentrations and temperatures, two independent electrolytic oxidation regeneration reaction tanks are configured for use by the horizontal immersion etching production line and the spray etching production line respectively.
[0046] The utility model can also be improved as follows: at least one of a level meter, a thermometer, an ORP meter, and a photoelectric colorimeter is installed in the solution flow exchange tank, and the working state of the electrolytic power supply is controlled according to the data of the sensor to ensure that the chemical reaction of the regenerated copper etching agent is carried out safely.
[0047] The utility model can also be improved as follows: a variable frequency pump or a combination of an adjustable opening valve and a pump is installed on the liquid flow pipeline between the etching production line and the solution flow exchange tank to adjust the input of the regeneration liquid or the liquid flow circulation speed between the two, so that multiple process parameters of the etching working liquid can be stabilized during the etching process to ensure the etching quality requirements.
[0048] Compared with the prior art, the utility model has the following beneficial effects.
[0049] 1. The utility model combines horizontal immersion and spray etching processing system with immersion and spray etching, which effectively reduces the oxidation of easily oxidized metal anti-corrosion layers such as silver and improves the etching quality of thick copper circuit boards.
[0050] 2. The utility model further adopts an electrolytic oxidation regeneration reaction tank to perform electrolytic oxidation regeneration on the etching working liquid on the horizontal immersion etching production line and / or the spray etching production line, and can also provide high redox potential etching liquid for the etching production line to improve production efficiency.
[0051] 3. The etching process implemented by the utility model is safe and reliable, and the equipment investment scale is small.
[0052] 4. The utility model can achieve a higher degree of automation and reduce the labor intensity of operators under the premise of meeting the improvement of etching process.
[0053] 4. When the utility model adopts the electrolytic oxidation regeneration reaction process, no external oxidant is required during the etching process, and there is no waste liquid increase, which meets the standard requirements for recycling in environmentally friendly production. BRIEF DESCRIPTION OF THE DRAWINGS
[0054] The utility model is further described below with reference to the accompanying drawings.
[0055] Figure 1 This is a schematic diagram of the structure of a horizontal immersion etching production line according to Example 1;
[0056] Figure 2 It is an etching processing system combining horizontal immersion and spraying according to Example 2 of the utility model;
[0057] Figure 3 It is the etching processing system combining horizontal immersion and spraying of Example 3 of the utility model;
[0058] Figure 3-1 for Figure 3 A magnified view of part A;
[0059] Figure 3-2 for Figure 3 A magnified view of part B;
[0060] Figure 4 This is a schematic diagram of the structure of a horizontal immersion etching production line of Example 3;
[0061] Figure 5 It is a schematic diagram of the structure of the insoluble absorbent cotton roller.
[0062] Reference numerals:
[0063] 1-electrolysis regeneration reaction tank, 2-horizontal immersion etching production line, 3-spray etching production line, 4-electrolysis tank partition, 5-electrolysis anode, 6-electrolysis cathode, 7-electrolysis power supply, 8-temporary storage tank, 9-sensor, 10-automatic detection feeder, 11-cold and hot temperature exchanger, 12-liquid flow agitator, 13-valve, 14-pump, 15-high redox potential solution, 16-etching waste liquid, 17-etching sub-liquid, 18-etching production circuit board, 1 9-overflow buffer tank, 20-jet water jet, 21-pipette or water jet, 22-nozzle, 23-clean water, 24-solid-liquid separator, 25-solution flow exchange tank, 26-frequency conversion pump, 27-adjustable opening valve, 28-metal copper, 29-acidic ferric chloride solution, 30-dilute sulfuric acid, 31-tail gas treatment tank, 32-electrolytic waste liquid after copper extraction, 33-transmission mechanism, 34-insoluble water-absorbing cotton roller, 35-etching solution, 36-immersion etching tank. DETAILED DESCRIPTION
[0064] The present invention is further described below through specific embodiments.
[0065] In the following embodiments, the electrolytic oxidation regeneration reaction tank, horizontal immersion etching production line, temporary storage tank, overflow buffer tank, and automatic detection and feeding controller used are all products produced by Guangdong Foshan Yegao Environmental Protection Equipment Manufacturing Co., Ltd. The electrolytic cell separators, spray etching production lines, sensors, solid-liquid separators, valves, and pumps used are all commercially available products. In addition to the above-mentioned products, those skilled in the art can also select other products with similar performance to the above-mentioned products listed in the utility model according to conventional selection, and all of them can achieve the purpose of the utility model.
[0066] Example 1
[0067] like Figure 1 As shown, it is a schematic diagram of the structure of the horizontal immersion etching production line of Example 1 of the utility model. The horizontal immersion etching production line 2 includes an immersion etching pool 36, and a circuit board conveying mechanism 33 and a liquid spray water knife 20 arranged in the pool, wherein the circuit board conveying mechanism 33 is located in the etching liquid 35 in the immersion etching pool 36, and the circuit board to be etched supported by it moves forward while being immersed in the etching liquid. There are several liquid spray water knives 20, which are respectively arranged above and below the transmission roller of the circuit board conveying mechanism 33.
[0068] The circuit board to be etched is a thick copper (1000 micron) circuit board.
[0069] The acidic etching solution mainly contains hydrochloric acid, cupric chloride and chloride salt.
[0070] The steps of etching production using the etching processing system of this embodiment are as follows:
[0071] (1) adding an acidic etching working solution 35 into a horizontal immersion etching production line and a spray etching production line;
[0072] (2) placing the circuit board into the spray etching production line for etching, adding an oxidant and an etching sub-liquid into the spray etching production line during the etching process to maintain the stability of the components and concentration of the etching working solution, and setting the etching time to etch until the thickness of the etched copper is reduced by 1 / 4 according to the etching rate;
[0073] (3) collecting the etched circuit board from the conveying outlet of the spray etching production line and transferring it to the horizontal immersion etching production line for etching. During the etching process, an oxidant and an etching sub-liquid are added to the horizontal immersion etching production line to maintain the stability of the components and concentration of the etching working solution, and the etching time is set according to the etching rate to etch until the thickness of the etched copper is reduced by 1 / 2;
[0074] (4) The etched circuit board is collected from the conveying outlet of the horizontal immersion etching production line and transferred to the spray etching production line for etching correction; during the etching process, oxidant and etching sub-liquid are added to the spray etching production line to maintain the stability of the components and concentration of the etching working solution; when the circuit board is collected from the spray etching production line when it is conveyed to the outlet, the etching is completed.
[0075] After the above steps, the thick copper circuit board is etched in the improved etching system so that the thick copper circuit board can meet the etching quality requirements.
[0076] Example 2
[0077] like Figure 2 As shown, it is a schematic diagram of the etching processing system combining horizontal immersion and spraying of Example 2 of the utility model, which includes an electrolytic oxidation regeneration reaction tank 1, a horizontal immersion etching production line 2, a spray etching production line 3, three temporary storage tanks 8, six sensors 9, three hot and cold temperature exchangers 11, three overflow buffer tanks 19, a solution flow exchange tank 25, and multiple valves and pumps.
[0078] The electrolytic oxidation regeneration reaction tank 1 is divided into an anode tank area and a cathode tank area by an electrolytic tank separator 4. An electrolytic anode 5 and an electrolytic cathode 6 are respectively arranged in the anode tank area and the cathode tank area. The electrolytic anode 5 is connected to the positive electrode of the electrolytic power supply 7, and the electrolytic cathode 6 is connected to the negative electrode of the electrolytic power supply 7. The electrolytic anode 5 is a platinum electrode, the electrolytic cathode 6 is conductive graphite, and the electrolytic tank separator 4 is an anion exchange membrane.
[0079] The horizontal immersion etching production line 2 has several liquid jet water knives 20 which are respectively arranged between the transmission rollers of the circuit board conveying mechanism 33 .
[0080] The solution flow exchange tank 25 is used for mixing and exchanging the etching working solution of the etching production line with the anode electrolyte of the anode tank area. The anode tank area of the electrolytic oxidation regeneration reaction tank 1 is connected to the solution flow exchange tank 25 in a circulation manner through a liquid flow pipeline; the horizontal immersion etching production line 2 and the spray etching production line 3 are respectively connected to the solution flow exchange tank 25 in a circulation manner through a liquid flow pipeline; wherein, the liquid flow pipelines for the above-mentioned liquid flow to flow into the solution flow exchange tank 25 are all provided with overflow buffer tanks.
[0081] This embodiment is also provided with temporary storage tanks 8-1, 8-2, and 8-3; specifically, the temporary storage tank 8-1 stores the etching sub-liquid, which is an acidic ferric chloride solution 29, and is connected to the horizontal immersion etching production line 2 and the spray etching production line 3; the temporary storage tank 8-2 is connected to the solution flow exchange tank 25, and is used to store the etching waste liquid 16; the temporary storage tank 8-3 is connected to the cathode tank area, and temporarily stores its overflow liquid.
[0082] The sensors 9-1 and 9-5 are acidity meters, sensors 9-2, 9-3 and 9-6 are redox potentiometers (ORP meters), sensor 9-4 is a liquid level meter, and sensor 9-7 is a specific gravity meter. Sensors 9-1 and 9-2 are arranged in the horizontal immersion etching production line 2, sensors 9-3 and 9-4 are arranged in the solution flow exchange tank 25, sensors 9-5 and 9-6 are arranged in the spray etching production line 3, and sensor 9-7 is arranged in the cathode tank area.
[0083] The pumps 26-1 and 26-2 provided on the pipeline from the solution flow exchange tank to the etching production line are variable frequency pumps, which are controlled by sensors 9-2 and 9-6 respectively.
[0084] The sensor 9-3 controls the opening or closing of the electrolytic power source 7 and the magnitude of its operating current.
[0085] The circuit board to be etched is a thick copper (1000 microns) circuit board 18 .
[0086] The acidic etching solution mainly contains hydrochloric acid, cupric chloride and ferric chloride.
[0087] The steps of etching production using the etching processing system of this embodiment are as follows:
[0088] (1) A high redox potential acidic etching working solution 15 is added to the anode tank area and solution flow exchange tank 25 of the horizontal immersion etching production line 2, the spray etching production line 3, the electrolytic oxidation regeneration reaction tank 1, and the acidic etching waste liquid is added to the cathode tank area of the electrolytic oxidation regeneration reaction tank 1.
[0089] Start pumps 14-10 and 14-11 to allow the etching working solution 15 to circulate in the anode tank area and the solution flow exchange tank 25. Sensor 9-3 controls the opening and closing of the electrolytic power supply 7 or adjusts the output electrolytic current according to the process setting value. In the process setting, the value of the redox potential of sensor 9-3 is higher than that of sensors 9-2 and 9-6.
[0090] The pump 26-1 is controlled by the sensor 9-2 to add the etching working solution with high redox potential that has been electro-oxidized in the solution flow exchange tank 25 to the horizontal immersion etching production line 2. The overflowing solution flows into the overflow buffer tank 19-1 and is pumped back to the solution flow exchange tank 25 by the pump 14-3.
[0091] According to the detection result of sensor 9-6, pump 26-2 is controlled to add the solution in solution flow exchange tank 25 to the spray etching production line 3, and the full liquid flows into buffer tank 19-2. Pump 14-7 is turned on to pump the solution back to solution flow exchange tank 25 for mixing and exchange.
[0092] (2) putting the circuit board 18 into the horizontal immersion etching production line 2 for etching, and controlling the pump 14-2 to add the etching liquid 29 according to the detection result of the sensor 9-1 during the etching process; after the circuit board 18 is corroded and thinned by the horizontal immersion etching production line, it is transferred to the spray etching production line 3 for etching correction;
[0093] According to the detection result of the sensor 9-5 of the spray etching production line 3, the pump 14-1 is controlled to add the etching sub-liquid 29 to maintain the spray etching process; when the circuit board 18 is transferred from the spray etching production line 3 to the outlet and collected, the etching is completed.
[0094] (3) During the etching process, since the etching sub-liquid 29 is controlled to be directed to the horizontal immersion etching production line 2 and the spray etching production line 3 respectively, the volume of the etching working liquid continues to increase. The sensor 9-4 in the solution flow exchange tank 25 controls the pump 14-4 to pump the excess etching waste liquid to the tank 8-2 for temporary storage through the detection result.
[0095] In the above etching process, the electrolytic oxidation regeneration reaction tank 1 needs to continuously oxidize the cuprous ions and divalent ferrous ions in the etching working solution into divalent cupric ions and trivalent ferrous ions in the anode tank area, while the electrolytic cathode continuously electrolyzes metallic copper 28.
[0096] After the above steps, the thick copper circuit board 18 is etched in the improved etching system so that the thick copper circuit board can meet the etching quality requirements.
[0097] Example 3
[0098] like Figure 3As shown, it is a schematic diagram of the etching processing system combining horizontal immersion and spraying of Example 3 of the utility model, which includes three electrolytic oxidation regeneration reaction tanks 1-1, 1-2 and 1-3, a horizontal immersion etching production line 2, a spray etching production line 3, two temporary storage tanks 8, multiple sensors 9, an automatic detection and feeding controller 10, three hot and cold temperature exchangers 11, three liquid flow agitators 12, eight overflow buffer tanks 19, a solution flow exchange tank 25, and multiple valves and pumps.
[0099] The electrolytic oxidation regeneration reaction tank is divided into an anode tank area and a cathode tank area by an electrolytic tank separator. The anode tank area and the cathode tank area are respectively provided with an electrolytic anode and an electrolytic cathode. The electrolytic anode is connected to the positive electrode of the electrolytic power supply, and the electrolytic cathode is connected to the negative electrode of the electrolytic power supply.
[0100] The electrolytic anode 5-1 of the electrolytic oxidation regeneration reaction tank 1-1 is a graphite electrode, the cathode 6-1 is a copper plate, and the electrolytic tank separator 4-1 is a bipolar membrane. The electrolytic anode 5-2 of the electrolytic oxidation regeneration reaction tank 1-2 is an insoluble anode with a titanium-based coating, the electrolytic cathode 6-2 is a titanium plate, and the electrolytic tank separator 4-2 is a reverse osmosis membrane. The electrolytic anode 5-3 of the electrolytic oxidation regeneration reaction tank 1-3 is a platinum electrode, the electrolytic cathode 6-3 is stainless steel; the electrolytic tank separator 4-3 is a proton membrane.
[0101] The horizontal immersion etching production line 2 has undergone corresponding structural improvements. Figure 1 The horizontal immersion production line shown in the figure is equipped with multiple suction pipes and suction water knives (such as Figure 4 As shown), the fluidity of the etching working solution in the immersion etching tank is enhanced and the external force impact of the liquid flow on the etched silver anti-corrosion layer is reduced.
[0102] The horizontal immersion etching production line 2 is connected to the solution flow exchange tank 25 through a pipeline for circulating liquid flow. The solution flow exchange tank 25 is respectively connected to the anode tank area of the electrolytic oxidation regeneration reaction tank 1-1 and 1-2 through an overflow buffer tank and a pipeline for circulating liquid flow. The spray etching production line 3 is directly connected to the anode tank area of the electrolytic oxidation regeneration reaction tank 1-3 through an overflow buffer tank 19-7 and a pipeline for liquid flow circulation.
[0103] The hot and cold temperature exchanger 11-1 is installed in the horizontal immersion etching production line 2, the hot and cold temperature exchanger 11-2 is installed in the solution flow exchange tank 25, and the hot and cold temperature exchanger 11-3 is installed on the spray etching production line 3, and the temperature of each etching working solution is controlled according to the process.
[0104] The sensor 9-1 is a thermometer, 9-2 is a pH meter, 9-3 is an ORP meter, 9-4 is a thermometer, 9-5 is an ORP meter, 9-6 is a liquid level meter, 9-7 is a hydrometer, 9-8 is a hydrometer, 9-9 is a hydrometer, 9-10 is a thermometer, 9-11 is a hydrometer, and 9-12 is an ORP meter. Among them, sensors 9-1, 9-2, and 9-3 are arranged in the horizontal immersion etching production line 2, sensors 9-4, 9-5, and 9-6 are arranged in the solution flow exchange tank 25, sensors 9-7, 9-8, and 9-9 are respectively arranged in the cathode tank area of the electrolytic oxidation regeneration reaction tanks 1-1, 1-2, and 1-3, and sensors 9-10, 9-11, and 9-12 are arranged in the spray etching production line 3.
[0105] This embodiment also has temporary storage tanks 8-1 and 8-2; the temporary storage tank 8-1 is connected to the cathode tank area of each electrolytic oxidation regeneration reaction tank, and is used to store the solution overflowing from each cathode tank area; the temporary storage tank 8-2 is connected to the horizontal immersion etching production line 2 and the spray etching production line 3, and is used to store the etching waste liquid 16.
[0106] The circuit board that needs to be etched is a silver anti-corrosion layer circuit board 18 .
[0107] The etching liquid is a tetraammine copper sulfate etching liquid, and its main components are ammonia water, ammonium sulfate and tetraammine copper sulfate. The etching sub-liquid 17 is a mixture of ammonia water and ammonium sulfate.
[0108] The process parameters of the etching working fluid of the horizontal immersion etching production line are different from those of the spray etching production line; one difference is that the temperature of the etching working fluid of the horizontal immersion etching production line is 55°C, which is 5°C higher than that of the spray etching production line; the second difference is that the ORP value of the etching working fluid of the spray etching production line is 120mv, which is 50mv higher than that of the spray etching production line; other parameters, such as copper ion concentration and pH value, are the same.
[0109] The pump 26 provided on the pipeline from the solution flow exchange tank to the horizontal immersion etching production line is a variable frequency pump, which is controlled by the sensor 9-3. The valve 27 provided on the pipeline from the spray etching production line to the solution flow exchange tank is an adjustable opening valve, which is combined with the pump 14-15 and controlled by the sensor 9-12.
[0110] This embodiment also provides a tail gas treatment tank 31 for receiving and treating the tail gas from the etching production line and the electrolytic oxidation regeneration reaction tank.
[0111] The detection signal input end of the automatic detection feeding controller 10 is connected to the detection signal output section of each sensor, and its control signal output end is connected to the control signal input end of at least one of the electrolysis power supply, etching power supply, pump, valve, and hot and cold temperature exchanger in the system of this embodiment.
[0112] The steps of etching production using the etching processing system of this embodiment are as follows:
[0113] (1) Add the etching working solution of the horizontal immersion etching production line to the anode tank area of the horizontal immersion etching production line and the electrolytic oxidation regeneration reaction tanks 1-1 and 1-2, and add the etching working solution of the spray etching production line to the anode tank area of the spray etching production line and the electrolytic oxidation regeneration reaction tank 1-3; and add the etching waste liquid to the cathode tank area of the electrolytic oxidation regeneration reaction tanks 1-1, 1-2 and 1-3 as the starting solution of the cathode electrolyte.
[0114] The automatic detection and feeding controller 10 processes the data transmitted by multiple sensors and issues instructions based on the detection and processing results to enable the system to automatically operate according to the pre-programmed program.
[0115] (2) Start pumps 14-4 and 14-5 to circulate the solution between the anode tank area in the electrolytic oxidation regeneration reaction tanks 1-1 and 1-2 and the solution flow exchange tank 25; start pump 14-15 to circulate the solution between the spray etching production line and the anode tank area in the electrolytic oxidation regeneration reaction tank 1-3.
[0116] According to the detection result of sensor 9-2, the pump on the sub-liquid adding pipeline is controlled to add etching sub-liquid to the horizontal immersion etching production line 2. According to sensor 9-3, pump 26 is controlled to add solution to the solution flow exchange tank 25, so that the etching working liquid of the horizontal immersion etching production line 2 is renewed, exchanged and oxidized. According to the detection result of sensor 9-12, the adjustable opening valve 27 is controlled, and under the operation of pumps 14-15, the etching working liquid of the spray etching production line 3 enters the anode tank area of the electrolytic oxidation regeneration reaction tank 1-3 for oxidation regeneration reaction, so as to obtain a high redox potential solution which flows back to the spray etching production line 3 to continue etching reaction.
[0117] The detection result of sensor 9-5 is used to control the on / off of electrolytic power supplies 7-1 and 7-2 and adjust the magnitude of the working current. The detection result of sensor 9-12 is also used to control the on / off of electrolytic power supply 7-3 and adjust the magnitude of the working current.
[0118] According to the detection result of sensor 9-1, the hot and cold temperature exchanger 11-1 is controlled to control the temperature of the etching working fluid of the horizontal immersion etching production line 2; according to the detection result of sensor 9-4, the hot and cold temperature exchanger 11-2 is controlled to control the temperature of the solution in the solution flow exchange tank 25; according to the detection result of sensor 9-10, the hot and cold temperature exchanger 11-3 is controlled to control the temperature of the etching working fluid of the spray etching production line 3.
[0119] (3) a silver anti-corrosion layer circuit board 18 is placed in the horizontal immersion etching production line 2 for etching. During the etching process, an etching sub-liquid is added to the horizontal immersion etching production line 2, and the etching working liquid and the etching working liquid treated by electro-oxidation in the solution flow exchange tank 25 circulate, so that the etching working liquid in the etching production line is supplemented with a divalent copper ammonia complex, i.e., a copper etching agent, to maintain a high redox potential. In this process, the electrolytic cathodes 6-1 and 6-2 electrolyze copper respectively.
[0120] After completing the horizontal immersion etching, the circuit board 18 is transferred to the spray etching production line for further etching. The etching sub-liquid 17 is also added to the spray etching production line 3 under process control. The etching working liquid circulates into the anode tank area of the electrolytic cell 1-3 to be oxidized, and after oxidation regeneration, it flows back to the spray etching production line 3 to participate in the etching reaction; in this process, the electrolytic cathode 6-3 electrolytically deposits metallic copper; the silver anti-corrosion layer circuit board 18 is transported from the spray etching line to the outlet for collection, and the etching is completed.
[0121] (4) During the etching process, etching liquid is added to the etching production line, and the etching waste liquid overflowing from the two etching production lines is collected and temporarily stored in the temporary storage tank 8-2.
[0122] In order to ensure the normal operation of the electrolytic oxidation regeneration reaction tanks 1-1, 1-2 and 1-3 during the etching process, the detection results of sensors 9-7, 9-8 and 9-9 are used to control pumps 14-10, 14-11 and 14-12 respectively, and etching waste liquid is added to the cathode tank areas of the electrolytic oxidation regeneration reaction tanks 1-1, 1-2 and 1-3 according to the process setting values; the overflow liquid from each cathode tank area is collected in the temporary storage tank 8-1.
[0123] During the etching process, the entire etching processing system is automatically detected by the feeding controller 10 to collect and process the data detected by each sensor, so that the etching processing system can operate safely according to the process setting program.
[0124] After the above-mentioned use steps, the silver-resistant layer circuit board 18 is etched in the improved alkaline etching system to meet the etching quality requirements of the silver-resistant layer-plated circuit board.
[0125] Comparative Example 1
[0126] The circuit board was etched using conventional spray etching equipment in the art. The circuit board to be etched and the etching solution used were the same as those in Example 1. After etching, it was found that the anti-corrosion layer on the circuit board surface was partially peeled off.
[0127] Comparative Example 2
[0128] The circuit board was etched using conventional spray etching equipment in the art. The circuit board to be etched and the etching solution used were the same as those in Example 3. After etching, it was found that most of the silver resist layer on the circuit board surface was dissolved and disappeared.
Claims
1. A horizontal immersion and spraying combined etching processing system, comprising at least one section of a spraying etching production line, characterized in that: Also included is at least one horizontal immersion etching line; The horizontal immersion etching production line mainly consists of an immersion etching tank / pool and a circuit board conveying mechanism, as well as a liquid jet water jet arranged in the tank / pool for exchanging etching liquid in the tank / pool; at least part of the circuit board conveying mechanism is located in the immersion etching tank / pool.
2. The etching processing system combining horizontal immersion and spraying according to claim 1, characterized in that: A pipette and / or a pipette knife are added to the horizontal immersion etching production line, that is, a pipette and / or a pipette knife are added to the immersion etching tank / pool.
3. The etching processing system combining horizontal immersion and spraying according to claim 2, characterized in that: The conveying mechanism on the horizontal immersion etching production line adopts a roller conveying device.
4. The etching processing system combining horizontal immersion and spraying according to claim 3, characterized in that: The conveying mechanism is an insoluble water-absorbing cotton roller combination.
5. The etching processing system combining horizontal immersion and spraying according to claim 4, characterized in that: At least one electrolytic oxidation regeneration reaction tank is added, and the electrolytic oxidation regeneration reaction tank is divided into an anode tank area and a cathode tank area by an electrolytic tank partition. The anode tank area is cyclically connected to the horizontal immersion etching production line and / or the spray etching production line through a liquid flow pipeline, so as to electrolytically oxidize and regenerate the copper etching agent of the etching working liquid on the horizontal immersion etching production line and / or the spray etching production line and return it to the etching production line.
6. The etching processing system combining horizontal immersion and spraying according to claim 5, characterized in that: An electrolytic anode and an electrolytic cathode are respectively arranged in the anode tank area and the cathode tank area of the electrolytic oxidation regeneration reaction tank, wherein the electrolytic anode is connected to the positive electrode of the electrolytic power supply, and the electrolytic cathode is connected to the negative electrode of the electrolytic power supply; The electrolysis anode is an insoluble electrode; the electrolysis cathode is a conductive material; The electrolytic cell separator is at least one of an anion exchange membrane, a bipolar membrane, a reverse osmosis membrane and a proton membrane.
7. The etching processing system combining horizontal immersion and spraying according to claim 6, characterized in that: At least one solution flow exchange tank is added; the solution flow exchange tank is arranged in one of the following ways: 1) The solution flow exchange tank is arranged at the connection between the horizontal immersion etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank, so that it is circulatedly connected with the horizontal immersion etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank through a liquid flow pipeline; or, 2) The solution flow exchange tank is arranged at the connection between the spray etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank, so that it is circulatedly connected with the spray etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank through a liquid flow pipeline; or, 3) The solution flow exchange tank is arranged at the connection between the horizontal immersion etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank, and at the connection between the spray etching production line and the anode tank area of the electrolytic oxidation regeneration reaction tank, so that it is respectively connected to the horizontal immersion etching production line, the spray etching production line, and the anode tank area of the electrolytic oxidation regeneration reaction tank through liquid flow pipelines for circulation.
8. The etching processing system combining horizontal immersion and spraying according to claim 7, characterized in that: A temporary storage tank is added; the temporary storage tank is connected to at least one of the electrolytic oxidation regeneration reaction tank, the horizontal immersion etching production line, the spray etching production line, and the solution flow exchange tank through a pipeline, or is arranged on a connecting pipeline between at least two of the above.
9. The etching processing system combining horizontal immersion and spraying according to claim 8, characterized in that: An overflow buffer tank is added; the overflow buffer tank is connected to at least one of the electrolytic oxidation regeneration reaction tank, the horizontal immersion etching production line, the spray etching production line, the solution flow exchange tank, and the temporary storage tank through a pipeline, or is arranged on a connecting pipeline between at least two of the above.
10. The etching processing system combining horizontal immersion and spraying according to claim 9, characterized in that: A hot and cold temperature exchanger is added in at least one of the electrolytic oxidation regeneration reaction tank, horizontal immersion etching production line, spray etching production line, solution flow exchange tank, temporary storage tank, and overflow buffer tank.
11. The etching processing system combining horizontal immersion and spraying according to claim 10, characterized in that: Additional sensors and automatic detection and feeding controllers are provided; the sensors are placed in at least one of the following positions: ① in an electrolytic oxidation regeneration reaction tank, ② in an etching production line, ③ in a container connected to an electrolytic oxidation regeneration reaction tank or an etching production line; the sensors are selected from at least one of a thermometer, an acidity meter, a hydrometer, a pH meter, a redox potentiometer, a photoelectric colorimeter, a pressure gauge, a liquid level gauge, and a chlorine gas detector; the detection signal input end of the automatic detection and feeding controller is connected to the detection signal output section of the sensor, and the control signal output end of the automatic detection and feeding controller is connected to the control signal input end of at least one of an electrolytic power supply, a pump, a valve, a hot and cold temperature exchanger, and an etching production line in the system.
12. The etching processing system combining horizontal immersion and spraying according to claim 11, characterized in that: Two independent electrolytic oxidation regeneration reaction tanks are configured for use by the horizontal immersion etching production line and the spray etching production line respectively.
13. The etching processing system combining horizontal immersion and spraying according to claim 12, characterized in that: A variable frequency pump or a combination of an adjustable opening valve and a pump is installed on the liquid flow pipeline between the etching production line and the solution flow exchange tank.