amides, polyvinyl alcohol and polyvinylpyrrolidone, surfactants, for example ethoxylated fatty acid glycerides, esters of fatty acids with polyols, for example pentaerythritol or trimethylolpropane, fatty alcohol ethoxylates with restricted homologue distribution and alkyl-oligoglucosides as well as electrolytes, such as sodium chloride or ammonium chloride.Suitable cationic polymers are, for exam