How to clean PCB?

Aug 23, 2022

As we all know, PCB will get dirty easily sometimes. So how do we clean dirt PCB and then use it again to reduce resource waste?

There is a magic water – PCB washing water – help us to do this magic play.

It is the abbreviation of circuit board chemical industrial cleaning agent, which is used to clean the flux and rosin remaining on PCB surface after soldering.

Types of the washing waters:

1.Chlorinated Solvent Washing Water:it is mixed with chlorinated solvent and other solvents, which dissolves rosin and removes flux quickly. So no residue and easy volatilization without drying after cleaning . For example: FREEBOND’s FRB-1.1.

2.Hydrocarbon Solvent Washing Water: With the widespread of hydrocarbon cleaning agents, hydrocarbon solvents are also used for the cleaning of PCBs; There are two kinds of hydrocarbon solvents – quick-drying type(have a better cleaning) and slow-drying one. It is environmental friendly, non-toxic, low in odor, and can be distilled and recycled. So it is mostly used for high-end precision PCBs. One sample is FRB-143.

3.Water-based Washing Water: with the merits of water-based washing water (eco-friendly, safely, non-toxic and non-volatile of irritant gases), it comes to people’s eyes recently. However, PCB with metal component pins should be taken into consideration. If the water is not anti-rust , the liquid may speed up the corrosion and rust of the pins.

The Usage of Those Waters:

1.Manual Brushing: firstly, dipping one of those waters on the PCB. Wait for some minutes. Then brush the circuit board. Because it will be helpful to the dissolution of rosin and the shedding of flux.

2.Ultrasonic cleaning: Generally, the board need to be placed in the fixture, to prevent damage of electronic components caused by ultrasonic vibration.

So firstly put the board in the fixture. Then place them in the ultrasonic cleaning tank. We need to choose the correct cleaning frequency and time of the ultrasonic wave. Finally, press the button to clean.