Defoamer
Foam looks like cleaning and often prevents it. In a machine the suppressor is what lets the water do mechanical work.
In detail
A defoamer is added to a formulation to stop it foaming, which sounds like sabotage and is the opposite. Foam is a poor medium for mechanical action: in a washing machine or a dishwasher a thick head of suds cushions the tumbling and the spray, absorbing the energy that was supposed to be dislodging soil. It also interferes with pumps and can push liquid out of a machine entirely. This is why detergent formulated for a machine and detergent formulated for a hand wash are not interchangeable, and why putting washing-up liquid in a dishwasher produces a kitchen floor covered in foam and dishes that are no cleaner. Defoamers are one of the functional classes a cleaning formulation is assessed in, and silicone-based ones are the commonest. Their presence is a sign that a product expects to be agitated.
Why
- Defoamer is explained by Mechanical action and abrasion
- Defoamer is explained by The four variables
Sources for this page
Sources
Safer Chemical Ingredients List — functional-use classes
United States Environmental Protection Agency (EPA), Safer Choice · Government or regulator
Relied on for: That defoamers are one of the functional-use classes in which cleaning-product ingredients are assessed. (states this directly)
Handbook of Detergents (Surfactant Science Series)
CRC Press / Taylor & Francis · Reference work
Relied on for: That foam interferes with the mechanical action of washing machines and dishwashers and that suds-suppressing agents are formulated in for that reason. (background and mechanism only)