Based on the principle "cleaning like with like", non-polar soiling such as oil and grease is best removed using non-polar cleaning media such as chlorinated hydrocarbons and non-halogenated hydrocarbons. With polar soiling such as salt and emulsions, on the other hand, the best cleaning results can be achieved with water, which is also polar.

Due to complex production processes and oils with high levels of additives, various bipolar cleaning tasks lie between these two extremes. Polar solvents are available for such applications. These single-component solvents ensure good cleaning results in both the polar and non-polar range.