Here’s the revised text:
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1. Three anti-paint is a specially formulated coating designed to safeguard PCB circuit boards and related equipment from environmental degradation.
2. This three-proof paint exhibits excellent resistance to both high and low temperatures; upon curing, it forms a transparent protective film that offers outstanding insulation, moisture resistance, leakage protection, shock resistance, dust resistance, corrosion resistance, aging resistance, and corona resistance.
3. Under real-world conditions, such as exposure to chemicals, vibrations, high dust levels, salt spray, humidity, and extreme temperatures, circuit boards may experience corrosion, softening, deformation, and mold growth, potentially leading to malfunctions.
4. The three-proof paint is applied to the surface of the circuit board, creating a protective film designed to withstand moisture, salt spray, and mildew.
5. In environments with chemicals (such as fuels and coolants), vibration, humidity, salt spray, and high temperatures, circuit boards that lack this protective coating are susceptible to corrosion, mold, and short circuits, which can result in circuit failures.
6. By employing three-proof paint, circuits can be effectively shielded from damage, thereby enhancing the reliability of the circuit board, increasing safety factors, and extending its service life.
7. Additionally, because three-proof paint prevents leakage, it enables the use of higher power and closer spacing between printed boards, facilitating the miniaturization of components.
—
**Specifications and Requirements of the Tri-Proof Paint Process**
**Painting Requirements:**
1. **Spray Paint Thickness:** The paint film thickness should be maintained between 0.05mm and 0.15mm, with a dry film thickness of 25µm to 40µm.
2. **Secondary Coating:** To achieve the necessary thickness for products with high protection requirements, a secondary coating may be applied after the initial paint film has cured, depending on specific needs.
3. **Inspection and Repair:** Conduct a visual inspection to ensure the coated circuit board meets quality standards, addressing any issues found. For instance, if three-proof paint contaminates pins or other protected areas, use tweezers to hold a cotton ball dipped in washing solution for cleaning, ensuring not to disturb the normal paint film during this process.
4. **PCB Component Replacement:** After the paint film has cured, component replacement can proceed as follows:
(1) Solder components directly using an electric soldering iron, then clean the area around the pad with a cotton cloth moistened with washing solution.
(2) Solder replacement components.
(3) Apply three-proof paint with a brush to the soldered area, allowing the paint film to dry and solidify.
**Operation Requirements:**
1. Workspaces for three-proof paint application must be clean and free of dust, with adequate ventilation, prohibiting entry of unauthorized personnel.
2. Wear appropriate protective gear, including masks or respirators, rubber gloves, and chemical safety goggles, to prevent personal injury.
3. Clean tools promptly after use, and securely close containers of three-proof paint.
4. Implement anti-static measures for circuit boards, ensuring they are not stacked and are placed horizontally during the coating process.
**Quality Requirements:**
1. The PCB surface must be free of paint drips or flow. Care should be taken to avoid drips on partially isolated areas during application.
2. The three-proof paint layer must be smooth, glossy, and uniformly thick to adequately protect the surface of pads, components, or conductors.
3. The paint layer and components must be devoid of defects like bubbles, pinholes, ripples, shrinkage holes, dust, or foreign objects, with no chalking or peeling. Note: Avoid touching the paint film before it has dried.
4. Components or areas that are partially isolated must not receive three-proof paint.
**Parts and Devices That Cannot Be Coated with Conformal Paint**
1. **Non-Coating Devices:** High-power radiators, heat sinks, power resistors, high-power diodes, cement resistors, code switches, potentiometers (adjustable resistors), buzzers, battery holders, fuse holders, IC holders, touch switches, relays, various socket types, pin headers, terminal blocks, DB9 connectors, and non-indicating LED lights.
2. Components specified in drawings as incompatible with three-proof paint.
3. Devices outlined in the “Non-Three-proof Components (Area) Catalogue” are prohibited from using three-proof paint. If non-coatable devices require coating, it must be done as specified by the R&D department or drawings.
**Precautions for the Three-Proof Paint Spraying Process**
1. The PCBA must feature a crafted edge, with a minimum width of 5mm for machine tracking.
2. Maximum PCBA dimensions are 410mm x 410mm, and minimum dimensions are 10mm x 10mm.
3. The maximum height of mounted PCBA components should not exceed 80mm.
4. Maintain a minimum distance of 3mm between sprayed and non-sprayed areas of components on the PCBA.
5. Thorough cleaning ensures the removal of corrosive residues, promoting better adhesion of the three-proof paint; preferred paint thickness is between 0.1mm and 0.3mm, with baking conditions at 60°C for 10-20 minutes.
6. Certain components, such as high-power radiating surfaces, power resistors, and others listed, should not be sprayed during the application process.
**Introduction to PCB Tri-Proof Paint Rework**
When repair is needed on a circuit board, expensive components may be removed individually, while the remainder can be discarded. However, a more common method involves removing the protective film from all or parts of the board and replacing damaged components one by one. Ensure that the substrate, adjacent electronic components, and nearby structures remain undamaged during protective film removal. Common methods include using chemical solvents, micro-grinding, mechanical means, and desoldering through the protective film. Chemical solvents are frequently employed, relying on the compatibility of the solvent with the protective film. Micro-grinding utilizes high-speed particles to abrade the protective film, while the mechanical method is straightforward. Desoldering through the protective film requires first creating a drain hole to allow molten solder to escape.
—
1. Three anti-paint is a specially formulated coating designed to safeguard PCB circuit boards and related equipment from environmental degradation.
2. This three-proof paint exhibits excellent resistance to both high and low temperatures; upon curing, it forms a transparent protective film that offers outstanding insulation, moisture resistance, leakage protection, shock resistance, dust resistance, corrosion resistance, aging resistance, and corona resistance.
3. Under real-world conditions, such as exposure to chemicals, vibrations, high dust levels, salt spray, humidity, and extreme temperatures, circuit boards may experience corrosion, softening, deformation, and mold growth, potentially leading to malfunctions.
4. The three-proof paint is applied to the surface of the circuit board, creating a protective film designed to withstand moisture, salt spray, and mildew.
5. In environments with chemicals (such as fuels and coolants), vibration, humidity, salt spray, and high temperatures, circuit boards that lack this protective coating are susceptible to corrosion, mold, and short circuits, which can result in circuit failures.
6. By employing three-proof paint, circuits can be effectively shielded from damage, thereby enhancing the reliability of the circuit board, increasing safety factors, and extending its service life.
7. Additionally, because three-proof paint prevents leakage, it enables the use of higher power and closer spacing between printed boards, facilitating the miniaturization of components.
—
**Specifications and Requirements of the Tri-Proof Paint Process**
**Painting Requirements:**
1. **Spray Paint Thickness:** The paint film thickness should be maintained between 0.05mm and 0.15mm, with a dry film thickness of 25µm to 40µm.
2. **Secondary Coating:** To achieve the necessary thickness for products with high protection requirements, a secondary coating may be applied after the initial paint film has cured, depending on specific needs.
3. **Inspection and Repair:** Conduct a visual inspection to ensure the coated circuit board meets quality standards, addressing any issues found. For instance, if three-proof paint contaminates pins or other protected areas, use tweezers to hold a cotton ball dipped in washing solution for cleaning, ensuring not to disturb the normal paint film during this process.
4. **PCB Component Replacement:** After the paint film has cured, component replacement can proceed as follows:
(1) Solder components directly using an electric soldering iron, then clean the area around the pad with a cotton cloth moistened with washing solution.
(2) Solder replacement components.
(3) Apply three-proof paint with a brush to the soldered area, allowing the paint film to dry and solidify.
**Operation Requirements:**
1. Workspaces for three-proof paint application must be clean and free of dust, with adequate ventilation, prohibiting entry of unauthorized personnel.
2. Wear appropriate protective gear, including masks or respirators, rubber gloves, and chemical safety goggles, to prevent personal injury.
3. Clean tools promptly after use, and securely close containers of three-proof paint.
4. Implement anti-static measures for circuit boards, ensuring they are not stacked and are placed horizontally during the coating process.
**Quality Requirements:**
1. The PCB surface must be free of paint drips or flow. Care should be taken to avoid drips on partially isolated areas during application.
2. The three-proof paint layer must be smooth, glossy, and uniformly thick to adequately protect the surface of pads, components, or conductors.
3. The paint layer and components must be devoid of defects like bubbles, pinholes, ripples, shrinkage holes, dust, or foreign objects, with no chalking or peeling. Note: Avoid touching the paint film before it has dried.
4. Components or areas that are partially isolated must not receive three-proof paint.
**Parts and Devices That Cannot Be Coated with Conformal Paint**
1. **Non-Coating Devices:** High-power radiators, heat sinks, power resistors, high-power diodes, cement resistors, code switches, potentiometers (adjustable resistors), buzzers, battery holders, fuse holders, IC holders, touch switches, relays, various socket types, pin headers, terminal blocks, DB9 connectors, and non-indicating LED lights.
2. Components specified in drawings as incompatible with three-proof paint.
3. Devices outlined in the “Non-Three-proof Components (Area) Catalogue” are prohibited from using three-proof paint. If non-coatable devices require coating, it must be done as specified by the R&D department or drawings.
**Precautions for the Three-Proof Paint Spraying Process**
1. The PCBA must feature a crafted edge, with a minimum width of 5mm for machine tracking.
2. Maximum PCBA dimensions are 410mm x 410mm, and minimum dimensions are 10mm x 10mm.
3. The maximum height of mounted PCBA components should not exceed 80mm.
4. Maintain a minimum distance of 3mm between sprayed and non-sprayed areas of components on the PCBA.
5. Thorough cleaning ensures the removal of corrosive residues, promoting better adhesion of the three-proof paint; preferred paint thickness is between 0.1mm and 0.3mm, with baking conditions at 60°C for 10-20 minutes.
6. Certain components, such as high-power radiating surfaces, power resistors, and others listed, should not be sprayed during the application process.
**Introduction to PCB Tri-Proof Paint Rework**
When repair is needed on a circuit board, expensive components may be removed individually, while the remainder can be discarded. However, a more common method involves removing the protective film from all or parts of the board and replacing damaged components one by one. Ensure that the substrate, adjacent electronic components, and nearby structures remain undamaged during protective film removal. Common methods include using chemical solvents, micro-grinding, mechanical means, and desoldering through the protective film. Chemical solvents are frequently employed, relying on the compatibility of the solvent with the protective film. Micro-grinding utilizes high-speed particles to abrade the protective film, while the mechanical method is straightforward. Desoldering through the protective film requires first creating a drain hole to allow molten solder to escape.
