Manufacturing process for high-sensitivity touch multilayer thin plate of notebook computer

Abstract

The invention discloses a manufacturing process of a high-sensitivity touch multi-layer thin plate of a notebook computer, which comprises the following steps of: cutting, pattern manufacturing, pressing, plate edge cutting, drilling, copper deposition, outer layer dry film, outer layer acid etching, etching an etching line in an outer layer copper foil exposed area through a vacuum etching line process, manufacturing a multi-layer PCB (Printed Circuit Board), solder mask printing, milling and the like. The invention aims to overcome the defects in the prior art, and provides the manufacturing process for the high-sensitivity touch multilayer thin plate of the notebook computer, which has the advantages of optimized process route, higher precision, higher production efficiency and lower production cost.

Description

Technical Field

[0001] The invention specifically relates to a manufacturing process of a high-sensitivity touch multi-layer thin plate for a notebook computer. Background Art

[0002] With the rapid development of information technology, laptops have become an indispensable part of people's work, study and entertainment. As an important interface for human-computer interaction, the sensitivity and response speed of the touch screen are directly related to the quality of the user experience. In order to meet users' demand for thinner and higher-performance devices, the design and manufacturing process of laptop internal components are also constantly evolving. In particular, the touch multilayer thin plate (Multilayer Touch Panel) not only needs to have high sensitivity to achieve accurate touch response, but also needs to ensure sufficient mechanical strength and stability to adapt to various environments in daily use.

[0003] In recent years, with the continuous expansion of the mobile device market, consumers have higher and higher requirements for laptop touch screens. In addition to the basic touch response function, users also expect the screen to support advanced functions such as multi-touch and gesture recognition, which requires the touch multi-layer thin plate to not only have high sensitivity, but also be able to stably transmit complex touch signals. However, the traditional touch multi-layer thin plate manufacturing process mainly relies on manual operation or combined with some mechanical processing methods, and there are still the following deficiencies: the processing technology is complicated and there are many process steps. Due to the lack of automated control means, the connection between the various processes is not tight enough, and quality problems such as line short circuit and open circuit are prone to occur, which affects the reliability and service life of the product; low precision, traditional processes are prone to errors in cutting, drilling and other links, resulting in inconsistent finished product sizes, affecting assembly accuracy, and making it difficult to make lighter and finer product sizes; low efficiency, complicated manual operation steps, long production cycle, and difficult to adapt to the requirements of large-scale production and fast delivery; high cost: traditional processes require a lot of manpower investment, and at the same time, the utilization rate of materials is low, which increases the manufacturing cost. In addition, complex processes also make it difficult to ensure the consistency and repeatability of products.

[0004] The present invention is just produced based on the above-mentioned shortcomings. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a manufacturing process for a laptop computer high-sensitivity touch multi-layer thin plate which can optimize the process route, has higher precision, higher production efficiency and lower production cost.

[0006] The present invention is achieved through the following technical solutions:

[0007] A manufacturing process of a high-sensitivity touch multilayer thin plate for a notebook computer comprises the following steps:

[0008] S1. Cutting: cutting out several original copper clad laminates according to size requirements;

[0009] S2, pattern production, transfer the pre-designed circuit pattern to the copper foil surface of the original copper clad laminate through the LDI exposure machine, and make the original copper clad laminate into an inner core board;

[0010] S3, pressing, stacking the inner core board, the prepreg PP and the outer copper foil in sequence, and using a press to laminate the inner core board, the prepreg PP and the outer copper foil together to form an inner board;

[0011] S4, cutting the board edge, using an automatic cutting machine to cut off the remaining edge of the inner layer board according to the pre-designed size drawing;

[0012] S5, drilling, using a drilling machine to process functional holes according to the pre-designed dimension drawing;

[0013] S6, copper deposition, forming a conductive layer on the hole wall of the functional hole through a VCP electroplating process;

[0014] S7, outer layer dry film, evenly stick the dry film on the outer copper foil, and heat the dry film and the copper foil to make them tightly bonded, irradiate the pre-designed circuit diagram onto the dry film through the LDI exposure machine, use a specific developer to remove the unexposed part of the dry film, expose the outer copper foil underneath, and keep the exposed part of the dry film unchanged to form a mask;

[0015] S8, acid etching of the outer layer, etching lines in the exposed area of ​​the outer copper foil through a vacuum etching line process to make a multi-layer PCB board;

[0016] S9, solder mask screen printing, use automatic spraying machine, screen printing equipment or inkjet printing process to evenly apply liquid solder mask on the surface of the entire multi-layer PCB board, and use screen printing equipment to print the pre-designed graphics on the surface of the multi-layer PCB board;

[0017] S10. Use a CNC gong machine to accurately cut the shape of the multi-layer PCB board, cut out the board according to the pre-designed size drawing, and make the finished product.

[0018] The above-mentioned manufacturing process of the laptop computer high-sensitivity touch multi-layer thin plate further includes the following steps between steps S2 and S3:

[0019] S2-1, inner layer AOI, the automatic optical inspection system collects the image information of the inner core board surface through the camera, and the inner layer automatic optical inspection system compares the image information with the pre-designed image, identifies the deviation, and promptly finds the defects of the inner core board surface pattern;

[0020] S2-2, browning treatment, using browning solution to change the color of the inner core board surface to brown or dark brown, forming a uniform, rough and highly active oxide layer on the copper foil surface of the original copper clad laminate.

[0021] In the manufacturing process of the laptop computer high-sensitivity touch multi-layer thin plate as described above, before step S5, the positioning mark hole is punched out using the dimension drawing pre-designed by the target drilling machine, and in step S5, the drilling machine processes the functional hole on the positioning mark hole.

[0022] The manufacturing process of the high-sensitivity touch multi-layer thin board for laptop computers as described above, after step S9, further includes the following steps: S9-1, placing the multi-layer PCB board in an oven, and baking it at a set temperature to completely cure the solder resist to form a solid protective layer.

[0023] The manufacturing process of the high-sensitivity touch multi-layer thin plate for laptop computers as described above, after step S8 and before step S9, also includes the following steps: S8-1, outer layer AOI, the automatic optical inspection system collects image information of the surface of the multi-layer PCB board through a camera, and the automatic optical inspection system compares the image information with the pre-designed image, identifies deviations, and promptly discovers defects in the surface pattern of the multi-layer PCB board.

[0024] The manufacturing process of the high-sensitivity touch multi-layer thin board for notebook computers as described above, after step S10, further includes the following steps: S11, Osp process, using the Osp process to attach a thin layer of OSP film to the copper surface that is not covered with ink after solder mask.

[0025] The manufacturing process of the high-sensitivity touch multi-layer thin plate for a laptop computer as described above, after step S7 and before step S8, further includes the following steps: S7-1, placing the multi-layer PCB board coated with dry film into a vacuum etching line for evacuation.

[0026] In the manufacturing process of the laptop computer high-sensitivity touch multi-layer thin plate as described above, in step S7-1, the ambient air pressure of the multi-layer PCB board is reduced to below 1000 Pa;

[0027] In the manufacturing process of the high-sensitivity touch multi-layer thin plate for notebook computers as described above, the thickness of the OSP film is between 0.2-0.29 um.

[0028] According to the manufacturing process of the high-sensitivity touch multi-layer thin board for notebook computers as described above, the surface roughness of the multi-layer PCB board after being manufactured into a finished product is between 0.2-0.4um.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] The manufacturing process of the high-sensitivity touch multi-layer thin plate for notebook computers provided by the present invention has a concise and clear workflow, adopts automated equipment for processing, has higher production accuracy, optimizes the process route, improves production efficiency, greatly reduces manual operation, improves product accuracy through precise control while avoiding material waste, and has lower production costs. The OSP production line using multi-layer thin plates can accurately control the resistance value of the OSP film thickness to improve product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 The schematic diagram of the manufacturing process of the high-sensitivity touch multilayer thin plate for notebook computers of the present invention is shown in FIG. Figure 1 ;

[0032] Figure 2 The schematic diagram of the manufacturing process of the high-sensitivity touch multilayer thin plate for notebook computers of the present invention is shown in FIG. Figure 2 . DETAILED DESCRIPTION

[0033] The invention will be further described below in conjunction with the accompanying drawings:

[0034] The directions described in the specification of the present invention, such as "up", "down", "left", "right", "front", "back", etc., are based on the directions of the drawings and are intended to facilitate the description of the relationship between the various components. They do not indicate the unique or absolute positional relationship between the various components. They are only one of the implementation methods of the invention and are not a limitation on its implementation method.

[0035] This embodiment provides a manufacturing process for a high-sensitivity touch multi-layer thin plate for a notebook computer. Figure 1 to Figure 2 , Figure 2 yes Figure 1 The continuation form includes the following steps:

[0036] S1. Cutting: Cut out several original copper clad laminates according to the size requirements, using an automatic cutting machine to ensure high cutting accuracy and fast speed;

[0037] S2. Graphics production: transfer the pre-designed circuit graphics to the copper foil surface of the original copper clad laminate through the LDI exposure machine, make the original copper clad laminate into the inner core board, and use the fully automatic LDI (laser direct imaging) exposure machine to transfer the image graphics, and accurately copy the designed circuit pattern on the copper foil surface (i.e. the conductive layer) of the original copper clad laminate to ensure that the graphics accuracy reaches the micron level, thereby ensuring clear edges and smooth lines, reducing the probability of problems such as broken wires and short circuits, and thus improving the quality of the finished product. The highly automated exposure machine can complete the graphics transfer work of large quantities of products in a short time, greatly improving the efficiency and capacity of production. Compared with traditional manual methods, automated equipment reduces the possibility of human error while ensuring a high degree of consistency and repeatability. Before this process, the oil, oxide and other impurities on the surface of the original copper clad board can be removed to ensure good adhesion, and then the photosensitive material is coated. A layer of photosensitive resin (dry film or wet film) is evenly coated on the cleaned copper foil surface as a medium for receiving image transfer. In the process, the designed circuit pattern is printed on a transparent film (film) using film, and then it is closely contacted with the inner layer board coated with photosensitive material, and then irradiated with ultraviolet light, using ultraviolet light or other light sources to irradiate the photosensitive material through the film, so that the blocked part remains unexposed, while the remaining area hardens. For LDI equipment, it can be directly exposed according to the digital design file without physical film; then through chemical development and chemical dissolution, after exposure, the unhardened photosensitive material will be dissolved by a specific chemical solution (developer), exposing the copper layer below, while the cured part remains in place, forming the required circuit pattern. After the process, it can be inspected and corrected. AOI inspection uses automatic optical inspection (AOI) equipment to check the quality of the pattern, find and mark any possible defects, such as broken wires, short circuits, etc. If problems are found, the defective parts can be repaired manually or automatically to ensure the smooth progress of subsequent processes. After cleaning and drying, after the development is completed, the plate is thoroughly cleaned to remove residual chemicals and fully dried to prepare for the next etching process.

[0038] S3, lamination, the inner core board, prepreg PP and outer copper foil are stacked in sequence, the inner core board is covered with prepreg on the upper and lower parts, and the outermost layer is covered with outer copper foil, one inner core board is one layer, and a 2-6 layer structure is adopted in this embodiment, and a press is used to laminate the inner core board with prepreg PP (Prepreg, i.e. semi-cured sheet) and outer copper foil to make an inner board, and suitable PP (polypropylene), copper foil and other materials are selected to ensure the mechanical strength and electrical properties of the final product, wherein the laminating machine used in the laminating process can be the one previously used by the applicant. The applied patent number is CN202023345428.X, and the name is a patent scheme for a multi-layer PCB board pressing device; as a preferred method, the stacked inner core boards constitute a stack, and the entire stack is placed in a vacuum bag and evacuated to remove air and make the layers tightly combined, and then the vacuum bag is placed in a hot press and pressed at a set temperature (generally 170°C to 180°C) and pressure. The pressing time can be set according to the thickness of the board and the number of layers, such as the pressing time is 30 minutes to 60 minutes.

[0039] S4, cutting the board edge, using an automatic cutting machine to cut off the remaining edge of the inner layer board according to the pre-designed size drawing, and maintaining the size consistency and edge flatness when removing the excess edge;

[0040] S5. Drilling: Use a drilling machine to process functional holes according to the pre-designed dimension drawing, that is, drill holes of the required diameter and position according to the design requirements. These functional holes are mainly used for vias, mounting holes and possible mechanical fixing points.

[0041] S6, copper deposition, forming a conductive layer on the hole wall of the functional hole through the VCP electroplating process, and ensuring uniform distribution of the coating through advanced copper deposition lines and VCP electroplating lines;

[0042] S7, outer layer dry film, evenly apply the dry film to the outer copper foil, and heat the dry film to make it tightly bonded with the copper foil, irradiate the pre-designed circuit diagram onto the dry film through the LDI exposure machine, use the fully automatic LDI exposure machine again to ensure the efficiency and quality of pattern transfer, use a specific developer to remove the unexposed part of the dry film, expose the outer copper foil below, and keep the exposed part of the dry film unchanged to form a mask. Compared with traditional wet film or liquid photoresist, dry film has higher resolution and can achieve more sophisticated circuit and pad design. Similarly, the pre-cleaning process and subsequent detection and repair process in step S2 can also be used in this step;

[0043] S8, outer layer acid etching, etching lines are etched in the exposed area of ​​the outer copper foil through the vacuum etching line process, and specific etching gases (such as chlorine, hydrogen fluoride, etc.) are injected into the cavity in a low-pressure environment. These gases will decompose into active ions under the action of the electric field, and the etching gas is excited by the radio frequency (RF) power supply to form plasma. The active ions and free radicals in the plasma can efficiently etch the exposed copper layer, and the active particles in the plasma selectively attack the copper layer that is not protected by the mask, gradually removing it, leaving the circuit pattern formed according to the design requirements, and making a multi-layer PCB board.

[0044] S9, solder mask screen printing, use automatic spraying machine, screen printing equipment or inkjet printing process to evenly apply liquid solder mask on the surface of the entire multi-layer PCB board, select ink with good adhesion and durability, and use screen printing equipment to print the pre-designed graphics on the surface of the multi-layer PCB board;

[0045] S10, use a CNC gong machine to accurately cut the shape of the multi-layer PCB board, cut out the board according to the pre-designed size drawing, and make the finished product;

[0046] S11, Osp process, the Osp process is used to attach a thin layer of OSP film to the copper surface that is not covered with ink after solder mask, which includes, pre-treatment: use special cleaning agent to remove grease, dust and other pollutants on the PCB surface to ensure that the copper surface is clean and flawless; micro-etching: slightly etch the copper surface to increase the roughness and improve the adhesion of the OSP film layer; coating OSP solution, using the immersion method: immerse the cleaned PCB in a tank containing OSP chemicals, and form a protective film on the copper surface through chemical reaction; curing, using natural drying, take out the PCB coated with OSP solution, and dry it naturally in the air for a few minutes to more than ten minutes, the specific time depends on the environmental conditions and OSP type, or use heating curing, short-term heating curing in a low-temperature oven (generally 80°C to 120°C, lasting 5 minutes to 30 minutes) to accelerate the reaction and enhance the performance of the film layer.

[0047] As a preferred implementation, the following steps are also included between steps S2 and S3:

[0048] S2-1, inner layer AOI, the automatic optical inspection system collects the image information of the inner core board surface through the camera, and the inner layer automatic optical inspection system compares the image information with the pre-designed image, identifies the deviation, and promptly finds the defects of the inner core board surface pattern;

[0049] S2-2, Browning treatment, use browning solution to change the color of the inner core board surface to brown or dark brown, and form a uniform, rough and highly active oxide layer on the copper foil surface of the original copper clad board. Browning refers to the process of chemically treating the surface of the inner copper foil to change its color to brown or dark brown. The purpose of this treatment is to improve the adhesion between different materials during subsequent lamination and enhance the bonding force: through browning treatment, a uniform, rough and highly active oxide layer can be formed on the copper surface, which helps to increase the bonding strength between insulating materials such as epoxy resin and copper foil, and prevent stratification or debonding. Browning can also prevent oxidation of the copper surface to a certain extent, ensuring that it maintains good conductivity before lamination. Subsequently, the inner core board will be cleaned after immersion or spraying, and dried for use.

[0050] As a preferred embodiment, before step S5, a positioning mark hole is punched out using a pre-designed dimension drawing using a target drilling machine. In step S5, a drilling machine processes a functional hole on the positioning mark hole, and a high-precision target drilling machine is used to ensure that the drilling position is accurate, thereby providing positioning for the subsequent functional hole processing process.

[0051] As a preferred implementation, after step S9, the following steps are further included:

[0052] S9-1, baking board text screen printing, put the multi-layer PCB board into the oven, bake it at the set temperature, make the solder resist completely solidify, solidify the screen printing text and symbols, ensure that the text and symbols are firmly attached, determine the appropriate baking temperature and time, ensure that the text is clearly visible and durable, for example, the baking temperature is 120℃ to 150°, and the baking time is 30 minutes to 60 minutes;

[0053] Preferably, a baking process is subsequently performed, in which the multi-layer PCB board is placed in an oven and baked at a higher temperature to form a solid protective layer. The appropriate baking temperature and time are determined, such as a baking temperature of 130°C to 170°C and a baking time of 30 minutes to 90 minutes.

[0054] As a preferred implementation, after step S10 and before step S11, the following steps are also included:

[0055] S10-1, electrical testing, using specialized testing equipment, such as flying probe tester, ICT (In-Circuit Test) tester, automatic optical inspection (AOI) combined with electrical testing, to test the finished product to verify whether the electrical performance of the PCB finished product meets the design requirements. Electrical testing can detect problems such as short circuit, open circuit, abnormal resistance value, etc., to ensure that each PCB has the correct electrical connection and function before leaving the factory;

[0056] S10-2, Final Inspection AVI, Final Inspection AVI (Automated Visual Inspection) is an important quality control step in the manufacturing process of multi-layer printed circuit boards (PCBs). In this step, automated visual inspection equipment is used to conduct a comprehensive appearance inspection of the finished PCB products to identify and record any possible defects.

[0057] As a preferred implementation, after step S8 and before step S9, the following steps are also included:

[0058] S8-1, Outer layer AOI, the automatic optical inspection system collects image information on the surface of the multi-layer PCB board through a camera. The automatic optical inspection system compares the image information with the pre-designed image, identifies deviations, and promptly discovers defects in the surface pattern of the multi-layer PCB board.

[0059] As a preferred implementation, after step S7 and before step S8, the following steps are also included:

[0060] S7-1, the multi-layer PCB board with the dry film is placed in a vacuum etching line for positive vacuum treatment, wherein the ambient air pressure of the multi-layer PCB board is reduced to below 1000 Pa;

[0061] Preferably, the thickness of the OSP film is precisely controlled to be between 0.2-0.29 um.

[0062] Preferably, the surface roughness of the multi-layer PCB board is precisely controlled to be between 0.2-0.4 um after being made into a finished product.

[0063] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A manufacturing process for a laptop computer high-sensitivity touch multi-layer thin plate, characterized in that: The following steps are included: S1. Cutting: cutting out several original copper clad laminates according to size requirements; S2, pattern production, transfer the pre-designed circuit pattern to the copper foil surface of the original copper clad laminate through the LDI exposure machine, and make the original copper clad laminate into an inner core board; S3, pressing, stacking the inner core board, the prepreg PP and the outer copper foil in sequence, and using a press to laminate the inner core board, the prepreg PP and the outer copper foil together to form an inner board; S4, cutting the board edge, using an automatic cutting machine to cut off the remaining edge of the inner layer board according to the pre-designed size drawing; S5, drilling, using a drilling machine to process functional holes according to the pre-designed dimension drawing; S6, copper deposition, forming a conductive layer on the hole wall of the functional hole through a VCP electroplating process; S7, outer layer dry film, evenly stick the dry film on the outer copper foil, and heat the dry film and the copper foil to make them tightly bonded, irradiate the pre-designed circuit diagram onto the dry film through the LDI exposure machine, use a specific developer to remove the unexposed part of the dry film, expose the outer copper foil underneath, and keep the exposed part of the dry film unchanged to form a mask; S8, acid etching of the outer layer, etching lines in the exposed area of ​​the outer copper foil through a vacuum etching line process to make a multi-layer PCB board; S9, solder mask screen printing, use automatic spraying machine, screen printing equipment or inkjet printing process to evenly apply liquid solder mask on the surface of the entire multi-layer PCB board, and use screen printing equipment to print the pre-designed graphics on the surface of the multi-layer PCB board; S10. Use a CNC gong machine to accurately cut the shape of the multi-layer PCB board, cut out the board according to the pre-designed size drawing, and make the finished product.

2. The manufacturing process of the notebook computer high-sensitivity touch multi-layer sheet according to claim 1, characterized in that: The following steps are also included between steps S2 and S3: S2-1, inner layer AOI, the automatic optical inspection system collects the image information of the inner core board surface through the camera, and the inner layer automatic optical inspection system compares the image information with the pre-designed image, identifies the deviation, and promptly finds the defects of the inner core board surface pattern; S2-2, browning treatment, using browning solution to change the color of the inner core board surface to brown or dark brown, forming a uniform, rough and highly active oxide layer on the copper foil surface of the original copper clad laminate.

3. The manufacturing process of the notebook computer high-sensitivity touch multi-layer sheet according to claim 1, characterized in that: Before step S5, a positioning mark hole is punched out using a dimension drawing pre-designed by a target drilling machine. In step S5, a drilling machine processes a functional hole on the positioning mark hole.

4. The manufacturing process of a notebook computer high-sensitivity touch multi-layer sheet according to claim 1, characterized in that: After step S9, the method further includes the following steps: S9-1. Place the multi-layer PCB board in an oven and bake it at a set temperature to completely cure the solder resist and form a solid protective layer.

5. The manufacturing process of a high-sensitivity touch multi-layer sheet for a notebook computer according to claim 1, characterized in that: After step S8 and before step S9, the following steps are also included: S8-1, Outer layer AOI, the automatic optical inspection system collects image information on the surface of the multi-layer PCB board through a camera. The automatic optical inspection system compares the image information with the pre-designed image, identifies deviations, and promptly discovers defects in the surface pattern of the multi-layer PCB board.

6. The manufacturing process of a notebook computer high-sensitivity touch multi-layer sheet according to claim 1, characterized in that: After step S10, the following steps are also included: S11, Osp process, uses Osp process to attach a thin layer of OSP film to the copper surface that is not covered with ink after solder mask.

7. The manufacturing process of a notebook computer high-sensitivity touch multi-layer sheet according to claim 1, characterized in that: After step S7 and before step S8, the following steps are also included: S7-1. The multi-layer PCB board covered with dry film is placed in the vacuum etching line for vacuum treatment.

8. According to the manufacturing process of the laptop computer high-sensitivity touch multi-layer thin plate according to claim 7, in step S7-1, the ambient air pressure of the multi-layer PCB board is reduced to below 1000 Pa.

9. The manufacturing process of a high-sensitivity touch multi-layer sheet for a notebook computer according to claim 6, characterized in that: The thickness of the OSP film is between 0.2-0.29 um.

10. The manufacturing process of a high-sensitivity touch multi-layer sheet for a notebook computer according to claim 1, characterized in that: The surface roughness of the multi-layer PCB board after being manufactured into a finished product is between 0.2-0.4um.

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