In PCBA processing process, the use of solder paste and flux will produce residual material, flux residues will gradually over time hardening and corrosion, such as metal halide salts formed on the PCB's adverse impact on reliability and service life, so the PCBA processing is completed, need to thoroughly remove residual flux, solder on the PCB board and other pollutants, In order to keep the surface of PCBA board clean and tidy, PCBA circuit board surface cleaning solvent on the market, so how do we choose?
1. Solvent Cleaning Agent
Solvent cleaning agent can be divided into hydrocarbon solvent, halogenated solvent, fluorinated solvent. Solvent-based cleaning agent is a self-cleaning and low residual cleaning agent, the disadvantage is easy to evaporate and volatile, in storage needs special attention. Due to the requirements of environmental protection policy, halogenated solvents and solvent use less fluoride in recent years, hydrocarbon cleaning agent need to pay attention to when using the machine and the fire prevention measures on the environment, but also want to consider the leakproof treatment of volatile organic compounds, only have to deal with these situations, can be used in small batch PCBA proofing hydrocarbon solvent cleaner. Hydrocarbon cleaner for some rosin and some non - cleaning flux residue, oil, dirt effect is better.
2. Water Based Cleaning Agent
Water-based cleaning agent can be used in most of the scene, just want to consider when selecting a water-based cleaning agent, circuit board surface metallization and the limitation of the compatibility, including lead oxide reactant, white metal, yellow metal, ink marks and compatibility of coating material, the second is the size, spacing and the complexity of assembly parts. Different types of flux residues vary in composition and the ability of water based cleaning materials to remove welding residues varies. At the same time, the water based cleaning agent cleaning process also atmosphere ultrasonic cleaning process and spray cleaning process, in the spray cleaning attack, the tolerance of foam is lower, no foam or foam is very small and can quickly dissipate.
When we know the residue on the PCBA circuit board residue composition, we can choose according to the actual needs to use solvent cleaning agent or water based cleaning agent, in meeting the cleaning conditions, we also need to consider environmental protection issues.
