How to remove the third anti-paint of PCB?
After using the three-proof paint, we will encounter more or less the problem of how to eradicate it. Next, the removal method is discussed.
There are many ways to remove the three-proof paint, such as methanol and alkaline activator solution, ethylene glycol ether and alkaline activator solution, toluene and xylene, but the most effective way is to select special solvents for different three-proof paint.
The chemical composition of the three anti-paint can be divided into six categories: acrylate, silicone, polyurethane, epoxy resin, nanometer and water-borne. It is not ideal to use methanol and alkaline activator solution or ethylene glycol ether and alkaline activator solution to clean.
Correct eradication measures:
Cleaning solvents (special solvents for different types of three-proof paints), mechanical cleaning and high temperature dissolving coatings: If the coated device is repaired, the component can be removed by directly touching the coatings on the welded soldering iron. Then install new components, and then clean the area with brush or solvent; also clean with solvent; after drying, re-coat with paint.
There are stripping agents specially used to eradicate polyurethane three-proof paint, and there should be places where the three-proof paint is sold. Or toluene can be used with methanol and alkaline activator solution or ethylene glycol ether and alkaline activator solution. It is the most commonly used method to dissolve and solidify the three-proof paint film with a specific chemical solvent, because it is simple and easy to operate and will not cause harm to the product.
How can the three-proof paint be removed for PCB repair and repaired easily?
Printed circuit board coated with three-proof paint is generally the final process in PCB assembly. However, in the final detection, electronic components may have shortcomings, which requires three-proof paint coatings to be repairable.
For electronic components used in harsh environments, PCB coated with three anti-paint can provide a variety of protection for PCB: moisture-proof, anti-mildew, dust-proof, insulation, maximum reduction of dendrite growth, release stress and so on. The three-proof paint circuit board makes the electronic components more durable, improves the reliability of electronic equipment and reduces the maintenance cost.
When the PCB needs to be repaired, the valuable components on the PCB can be taken out by themselves and the rest can be discarded. But the more commonly used method is to remove all or part of the protective film on the circuit board and replace the damaged components one by one. When removing the protective film of the three-proof paint circuit board, it is necessary to ensure that it does not endanger the substrate under the components, other electronic components, structures adjacent to the repairing orientation, etc. The removal methods of protective film mainly include chemical solvents, micro-grinding, mechanical methods and dismantling and welding through protective film.
The article originated from Jiangmen single-sided and double-sided circuit boards.http://www.yonghongpcb.com