The simplest way to inactivate any detergents left in the fabric is to neutralise the pH to between 6.5 and 7.5 through addition of a small amount of acetic acid. Through this method, the activity of the alkali and surfactants is eliminated.
For fabrics with a high content of synthetic fibres it may be necessary to add small amounts of cationic surfactants that can neutralise the charges of anionic surfactants and thus prevent static electricity. Using non-ionic or amphoteric surfactants normally makes such additions unnecessary.
Sometimes the fabric softeners also include small amounts of perfume to provide a pleasant scent. Please refer to the section on ‘other substances’ for further info.
Acetic acid is not a fabric softener in principle but is often used for this purpose in professional laundries.
Acetic acid is a weak organic acid – the key ingredient in vinegar. It is readily degradable and has no adverse effects in the environment except for the use of oxygen for degradation. It is also readily degradable under anaerobic conditions.
Acetic acid has to be stored and handled with care