Manufacturing procedure protective film easy for automatic laser windowing and preparation method of manufacturing procedure protective film

Abstract

The invention relates to the technical field of manufacturing process protective films, in particular to a manufacturing process protective film facilitating automatic laser windowing and a preparation method thereof.The manufacturing process protective film is prepared from, by weight, 80-120 parts of PVC resin powder, 20-45 parts of plasticizer, 1-5 parts of liquid stabilizer and 0.1-1 part of powder stabilizer.By optimizing a product formula system, the manufacturing process protective film facilitating automatic laser windowing is obtained. The provided product is used for the gold plating process of the golden finger of the PCB, a non-gold-plated area is protected, the mechanical property is just cut off by laser, the windowing efficiency is improved, meanwhile, the situation that the golden finger area of the circuit board below is burnt due to the fact that the protective film is broken down in the laser cutting process is avoided, and the actual application requirement is better met.

Description

Technical Field

[0001] The invention relates to the technical field of process protection films, in particular to a process protection film that is easy to automatically open a window with laser and a preparation method thereof. Background Art

[0002] The circuit board gold finger refers to an electronic component that is shaped like a finger and is usually located at one or both ends of the circuit board. It is used to connect to the slots of other circuit boards or devices to achieve the transmission of electrical signals. The surface of the circuit board gold finger is usually plated with a layer of gold or other metal to improve its conductivity and wear resistance. In the "gold finger" electroplating process of the circuit board, a process protective film needs to be used, which is attached to the surface of the circuit board to protect the non-electroplating area from leaking the plating solution, while the "gold finger" area needs to be automatically laser cut to cover the protective film in the area to expose the area for subsequent electroplating. The operation of automatically laser cutting the gold finger area is called "windowing" in the industry. In the process of "windowing", the process protective film needs to have mechanical properties that are just cut off by laser cutting to improve the efficiency of "windowing", but it cannot be too weak, which makes it very easy to break through the protective film during laser cutting and burn the "gold finger" area of ​​the circuit board below. A Chinese utility model (authorization announcement number CN209017364U) discloses a blue glue, which includes a base film layer and a coating layer arranged in sequence from top to bottom; it is composited by a polyvinyl chloride based film layer with a thickness of 50-100μm and an acrylic pressure-sensitive adhesive coating layer with a thickness of 5-25μm, and is mainly used to protect the circuit board from glue residue and avoid the phenomenon of bare copper residue in subsequent process glue. However, the performance of the polyvinyl chloride film layer needs to be further optimized to better meet the actual use requirements of laser automatic window opening. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a process protective film that is easy for automatic laser window opening. By optimizing the product formula system, the provided product can be used in the "gold finger" gold plating process of PCB circuit boards to protect non-gold-plated areas, and the mechanical properties are just cut off by laser cutting, thereby improving the "window opening" efficiency. At the same time, it avoids the protective film being penetrated during laser cutting and causing the "gold finger" area of ​​the circuit board below to be burned, thereby better meeting actual application needs.

[0004] On the one hand, the present invention provides a process protective film that is easy to open windows automatically by laser. The raw materials for its preparation include at least the following components by weight: 80-120 parts of PVC resin powder, 20-45 parts of plasticizer, 1-5 parts of liquid stabilizer, and 0.1-1 part of powder stabilizer.

[0005] As a preferred technical solution, the raw materials for preparing the process protection film that is easy to open windows automatically by laser also include 1-5 parts of colorant by weight.

[0006] As a preferred technical solution, the process protective film that is easy to open windows automatically by laser, its preparation raw materials include at least the following components by weight: 100 parts of PVC resin powder, 30-40 parts of plasticizer, 2-3 parts of liquid stabilizer, 0.3-0.6 parts of powder stabilizer, and 2-4 parts of colorant.

[0007] As a preferred technical solution, the PVC resin powder is calcium carbide process PVC resin powder.

[0008] As a preferred technical solution, the polymerization degree of the PVC resin powder is 800-1000.

[0009] As a preferred technical solution, the plasticizer at least includes an organic ester plasticizer.

[0010] As a preferred technical solution, the organic ester plasticizer is selected from at least one of dioctyl phthalate (DOP) and diisononyl phthalate (DINP), preferably dioctyl phthalate (DOP).

[0011] As a preferred technical solution, the plasticizer also includes epoxidized soybean oil.

[0012] Preferably, the mass ratio of the organic ester plasticizer to the epoxidized soybean oil is (25-35):(3-5), preferably (25-35):5.

[0013] As a preferred technical solution, the liquid stabilizer is selected from at least one of a lead salt liquid stabilizer, a calcium zinc liquid stabilizer, a barium zinc liquid stabilizer, an organic tin liquid stabilizer, and an organic antimony liquid stabilizer, preferably a barium zinc liquid stabilizer, model PV4022, sourced from Guangzhou Baisha Plastic New Materials Co., Ltd.

[0014] As a preferred technical solution, the powder stabilizer is selected from at least one of a lead salt stabilizer, a calcium zinc stabilizer, a barium zinc stabilizer, an organic tin stabilizer, and a rare earth stabilizer, preferably PV-4031, which is sourced from Guangzhou Baisha Plastic New Materials Co., Ltd.

[0015] The protective film provided by the present invention is mainly used in the gold-plating process of the "gold finger" of the PCB circuit board. In the early stage of the present invention, the ethylene-based PVC resin powder with a polymerization degree of 1000-1200 was used to prepare the protective film, but the problem of difficulty in opening the window occurred during the window opening process. The present invention unexpectedly discovered during the exploration process that the protective film prepared by using calcium carbide-based PVC resin powder, especially calcium carbide-based PVC resin powder with a polymerization degree of 800-1000, has a suitable elongation and tensile strength, and can meet the application requirements of the laser automatic window opening process. Furthermore, the present invention introduces organic ester plasticizers, epoxy soybean oil and barium zinc liquid stabilizers in combination with powder stabilizers in the optimization system, and the raw materials work together to improve the flexibility, ductility and processing stability of the PVC film, ensure the product quality and mechanical properties of the PVC film, and better meet the actual application requirements.

[0016] On the other hand, the present invention provides a method for preparing a process protective film that is easy to open windows automatically by laser, which comprises at least the following steps: adding PVC resin powder, plasticizer, liquid stabilizer, powder stabilizer and colorant into an internal mixer for pre-plasticization, then using an extruder or a plastic training machine for plasticization, then calendering into a film, and cooling and solidifying to obtain the film.

[0017] The protective film provided by the invention has readily available raw materials, a simple preparation method, high production efficiency, and is easy to realize large-scale industrial production.

[0018] Beneficial Effects

[0019] 1. The present invention provides a process protective film that is easy to open windows automatically by laser. By optimizing the product formula system, the provided product can be used in the gold-plating process of the "gold finger" of the PCB circuit board to protect the non-gold-plated area, and the mechanical properties are just cut off by laser cutting, thereby improving the "window opening" efficiency and avoiding the breakdown of the protective film during laser cutting, resulting in burning of the "gold finger" area of ​​the circuit board below, thereby better meeting the actual application needs.

[0020] 2. The protective film prepared by the present invention using calcium carbide PVC resin powder, especially calcium carbide PVC resin powder with a polymerization degree of 800-1000, has a suitable elongation (MD and CD) and can meet the application requirements of the laser automatic window opening process.

[0021] 3. The present invention introduces organic ester plasticizers, epoxy soybean oil and barium zinc liquid stabilizers in combination with powder stabilizers into the optimized system. The raw materials work together to improve the flexibility, ductility and processing stability of the PVC film, thereby ensuring the product quality and mechanical properties of the PVC film and better meeting the actual application requirements.

[0022] 4. The process protection film provided by the present invention effectively improves the efficiency of circuit board window opening, reduces the failure rate of automatic laser window opening, and reduces the proportion of manual secondary rework, thereby achieving the effect of cost saving.

[0023] 5. The raw materials of the protective film provided by the present invention are easily available, the preparation method is simple, the production cost is low, the production efficiency is high, and it is easy to realize large-scale industrial production. DETAILED DESCRIPTION

[0024] Examples 1-7

[0025] Embodiments 1-7 of the present invention provide a process protection film that is easy to automatically open a window by laser. The formula is shown in Table 1 in parts by weight.

[0026] Table 1

[0027]

[0028]

[0029] In Table 1: PV4022 and PV-4031 are from Guangzhou Baisha Plastic New Materials Co., Ltd.; PV4011 is from Guangdong Honglida Synthetic Materials Technology Co., Ltd.; PVE03 is from Guangdong Kucai Plastic Technology Co., Ltd. The polymerization degree of ethylene-based PVC resin powder is 1000±50, the model is s-PVC, and it is from Huayi; the polymerization degree of calcium carbide-based PVC resin powder is 950±50, the model is SG5, and it is from Yougubang.

[0030] On the other hand, Examples 1-7 of the present invention provide a method for preparing a process protective film that is easy for laser automatic window opening, comprising the following steps: adding PVC resin powder, plasticizer, liquid stabilizer, powder stabilizer, and colorant to an internal mixer for pre-plasticization, then using a plasticizer for plasticizing and plasticizing, then calendering into a film, and cooling and solidifying to obtain the film.

[0031] The thickness of the process protection film that is easy to open windows automatically by laser is 0.086 mm.

[0032] Performance Testing

[0033] 1. Referring to GB / T7753, the elongation at break (MD elongation and CD elongation) of the process protective film easy for laser automatic window opening provided in Examples 1-7 was tested. The test results are shown in Table 2.

[0034] Table 2

[0035]

[0036]

[0037] 2. The process protection film provided in Example 1-7 is compounded with Shuocheng J031 glue (the thickness of the glue film is 9±2um) to obtain blue glue, and the blue glue is covered on a four-row gold finger circuit board (with a 5mm margin of blue glue) at 80°C. The operator uses a machine (compressed air volume ≥500M / min, Zhengfeng Laser PTL-4010 / Automation Co., Ltd. Shenzhen) to perform laser automatic window opening. If the film is cut, it is recorded as successful window opening. If the film cannot be cut, it is recorded as difficult window opening. The window opening results are shown in Table 3.

[0038] Table 3

[0039]

Claims

1. A process protective film that is easy to open automatically by laser, characterized in that: The raw materials for its preparation include at least the following components by weight: 80-120 parts of PVC resin powder, 20-45 parts of plasticizer, 1-5 parts of liquid stabilizer and 0.1-1 part of powder stabilizer.

2. The process protective film that is easy to open windows automatically by laser according to claim 1, characterized in that: By weight, the raw materials for preparing the process protection film that is easy to open windows automatically by laser also include 1-5 parts of colorant.

3. The process protective film that is easy to open windows automatically by laser according to claim 2, characterized in that: The process protective film that is easy to open windows automatically by laser, is prepared from raw materials that include at least the following components by weight: 100 parts of PVC resin powder, 30-40 parts of plasticizer, 2-3 parts of liquid stabilizer, 0.3-0.6 parts of powder stabilizer, and 2-4 parts of colorant.

4. The process protective film that is easy to open windows automatically by laser according to claim 3, characterized in that: The PVC resin powder is calcium carbide process PVC resin powder.

5. The process protective film that is easy to open windows automatically by laser according to claim 4, characterized in that: The polymerization degree of the PVC resin powder is 800-1000.

6. The process protection film that is easy to open windows automatically by laser according to claim 5, characterized in that: The plasticizer at least includes an organic ester plasticizer.

7. The process protection film that is easy to open windows automatically by laser according to claim 6, characterized in that: The plasticizer also includes epoxidized soybean oil.

8. The process protection film that is easy to open windows automatically by laser according to claim 7, characterized in that: The mass ratio of the organic ester plasticizer to the epoxidized soybean oil is (25-35):(3-5).

9. The process protection film that is easy to open windows automatically by laser according to claim 2, characterized in that: The liquid stabilizer is selected from at least one of a lead salt liquid stabilizer, a calcium zinc liquid stabilizer, a barium zinc liquid stabilizer, an organic tin liquid stabilizer, and an organic antimony liquid stabilizer.

10. A method for preparing a process protective film that is easy to automatically open a window by laser according to any one of claims 2 to 9, characterized in that: At least the following steps are included: PVC resin powder, plasticizer, liquid stabilizer, powder stabilizer and colorant are added to an internal mixer for pre-plasticization, and then plasticized and plasticized by an extruder or a plastic training machine, and then calendered into a film, and the film is obtained after cooling and solidification.

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