It may seem like detergents have been part of our lives forever, but the truth is that the first detergents only began to be sold less than 90 years ago. In 1920, washing machines were still running on soap flakes – and with many problems: poor efficiency with hard water, forming of dirt deposits and damage to coloured clothing.
Detergents are long molecules with a tail that mixes well with fat and a head that mixes well with water. The detergent molecules surround the fat particles, turning the head that “likes” water to the outside, thus allowing stains to be captured and dissolved.
Detergents have been subject of constant improvements to increase their cleaning power, to better protect coloured clothing and to have a lower environmental impact.
A “detergent with gluttons” was famous in the past: a detergent mixed with enzymes. The role of the enzymes (or gluttons) was to attack the protein, fats and carbohydrates chains, breaking them into more soluble pieces, thus helping to remove food stains.
Another curious innovation was the addition of “optical whiteners” which are chemicals that don’t actually contribute to cleaning but attach themselves to fabrics and make them look whiter – and are responsible for detergents that “wash whiter than white”.
More recently we have several detergents on the market that use oxygen to oxidize the dirt – oxidation causes discoloration of the pigments common in fruits and other foods and also aids solubility.
But the future is in environment and clothes-friendly detergents. Research in this area is still very active and the results will soon be inside your washing machine.
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