1) Solvent types

1. Aliphatic hydrocarbons such as petroleum solvents Benzene, Toluene, Kerosene.
2. Aromatic hydrocarbons such as coal tar solvents
3. Non-combustible solvents such as Chlorinated hydrocarbons, Fluorinated chlorinated hydrocarbons and trichloroethylene
4. Polar solvents such as Ketone, Alcohol, and Phenol
5. Emulsification solvents, biphasic solvents, emulsion cleaners, etc.
6. Others

2) Application methods

1. Immersion (immersion cleaning, solvent heated and used as warm liquid)
2. Immersion and mechanical method combined (work being rotated/vibrated, solvent flowed
3. Spray cleaning
4. Steam cleaning (Dissolving power is increased when the solvents are vaporized but will require vapor recovery system) Shown in [Fig.1]
5. Ultrasonic cleaning (An oscillator is placed in the immersion tank and the solvent is vibrated)

3) Applicable areas

1. Rough cleaning of heavy soiling
2. Pre-cleaning for pre-processes
3. When water based cleaning solution cannot be used
4. When hydrophilic surfaces is not needed
5. When rapid cleaning is needed
6. Precision cleaning

4) Characteristic

This method has high penetration ability on soiling and effective even at low temperatures. But since the organic solvents are inflammble, safety measures for the operators and environmental concerns of volatile organic compounds will increase the costs.