According to customers requires, Cirket also have conformal coating service. PCBA conformal coating has excellent insulation, moisture-proof, leakage-proof, shock-proof, dust-proof, corrosion-proof, anti-aging, mildew-proof, anti-part loosening and insulation corona resistance properties, which can extend the storage time of PCBA. Cirket is always using Spraying which also the most commonly used coating method in the industry.
Cirket PCBA conformal coating spraying process flow
1. Required tools
Conformal coating paint, paint box, rubber gloves, mask or gas mask, brush, adhesive tape, tweezers, ventilation equipment, drying rack and oven.
2. Spraying steps
Painting A side → surface drying → painting B side → curing under the room temperature
3. Coating requirements
(1) Clean and dry the board to remove moisture and water of the PCBA. The dust, moisture and oil on the surface of the PCBA to be coated must be removed first so that the coating can fully exert its protective effect. Thoroughly cleaning can ensure that corrosive residues are completely removed and the conformal coating adheres well to the surface of the circuit board. Baking conditions: 60°C, 10-20 minutes. The best effect for coating is spraying when the board is hot after being taken out of the oven.
(2) When brushing the conformal coating, the coating area should be larger than the area occupied by the components to ensure that all components and pads are covered.
(3) When brushing the conformal coating, the circuit board should be placed as flat as possible. There should be no dripping after brushing. The coating should be smooth and there should be no exposed parts. The thickness should be between 0.1-0.3mm.
(4) Before brushing or spraying conformal coating, Cirket workers ensure the diluted conformal coating is fully stirred and left for 2 hours before brushing or spraying. Use a high-quality natural fiber brush to gently brush and dip at room temperature. If using the machine , the viscosity of the coating should be measured (using a viscosity tester or flow cup) and the viscosity can be adjusted with a diluent.
• The circuit board components should be immersed vertically in the coating tankat least i minute until the bubbles disappear and then slowly removed. Please note that the connectors should not be immersed unless they are carefully covered. A uniform film will form on the surface of the circuit board. Most of the paint residue should flow back from the circuit board to the dipping machine. TFCF has different coating requirements. The speed of dipping the circuit board or components should not be too fast to avoid excessive bubbles.
(6) If there is a crust on the surface when using it again after dipping, remove the skin and continue to use it.
(7) After brushing, place the circuit board flat on the bracket and prepare for curing. It is necessary to heat to accelerate the curing of the coating. If the coating surface is uneven or contains bubbles, it should be placed under the room temperature for a longer time before curing in a high-temperature furnace to allow the solvent to flash out.
Precautions
1. During the spraying process, some components cannot be sprayed, such as: high-power heat dissipation surface or heat sink components, power resistors, power diodes, cement resistors, dip switches, adjustable resistors, buzzers, battery holders, fuse holders (tubes), IC holders, touch switches, etc.
2. It is forbidden to pour the remaining three-proof paint back into the original storage container. It must be stored separately and sealed.
3. If the workroom or storage room is closed for a long time (more than 12 hours), ventilate it for 15 minutes before entering.
4. If it accidentally splashes into the glasses, please open the upper and lower eyelidsimmediately and rinse with running water or saline, and then seek medical treatment.
Media Contact
Company Name: Shenzhen Cirket Electronics Co., Ltd.
Email: Send Email
Country: China
Website: https://www.cktpcba.com/
