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A 2-in-1 shampoo is a shampoo that can both cleanse and condition a person’s hair. A bottle of 2-in-1 shampoo has both cleansing molecules as well as conditioning molecules, an innovation made possible during the 1980s and spearheaded by Procter & Gamble™. The introduction of 2-in-1 shampoo made the masses interested in conditioners, whether in 2-in-1 bottles or single bottles. As of 2005, more than 20 percent of all the shampoos manufactured worldwide are 2-in-1 shampoos.
One major problem the innovators encountered was how to combine oil-removing cleansers and oil-based nourishing conditioners. Chemistry, however, made it possible for cleansing molecules and conditioning molecules to stay together in one bottle by using a micro-suspension method. The micro-suspension method allows the conditioning molecules to be suspended in a bottle of shampoo, preventing them from mixing with the surfactants.
There are different types of surfactants, but the one used specifically for 2-in-1 shampoos is the anionic surfactant. Anionic surfactants, like sodium lauryl sulphate, sodium laureth sulphate, and ammonium lauryl ether sulphate, are effective when it comes to cleansing and lathering. The surfactants are bound together by polymers, which are responsible for the suspension of the conditioning molecules and preventing them from mixing with the anionic surfactants by engulfing each one. Polymers, which have conditioning properties that help condition hair, release conditioning oils like silicone shortly after the rinsing process.
When a 2-in-1 shampoo is lathered on a person’s hair, the surfactants in it attract grime and excess oil that accumulate on the hair and scalp. Once all the dirt and oil attach themselves to the surfactant, the rinsing process gets rid of them, cleaning both the hair and scalp. The polymers and conditioning molecules are not soluble by water and become separated from the dirt-containing surfactants.
Without the surfactants, the polymers release conditioning molecules into the hair and scalp, and the conditioning process starts to take place. The conditioning molecules are believed to have a positive charge, while the damaged hairs are believed to have a negative charge. It is thought that their opposite charges bind the conditioning molecules to the hair and scalp.
The conditioning molecules coat individual hairs and fill out rough areas, smoothing the hair. Hair tangles are minimized because the coating decreases friction between hairs. Smooth hair makes hair pigments reflect more light, making the hair look shinier. Cationics, another type of surfactant, are mainly responsible for the conditioning properties of a 2-in-1 shampoo.