Being soap free means we use ingredients other than soap to formulate our products. Many solid shampoos are soap based, but ours is Sydnet based (short for 'synthetic' + 'detergent'), meaning the surfactants are produced synthetically by combining plant oils with other natural molecules.Soap is made out of oil and lye combined and heated, resulting in a chemical reaction called saponification. In soap, the pH balance (or acid-base balance) is around 9, which is alkaline and opens up hair cuticles, letting water in and in turn weakening and damaging hair. We use surfactant-cleaning agents made from all vegetable, renewable resources, primarily coconut. These impart extra mildness on your hair and scalp with a balanced4.5- 5.5 pH, keeping your cuticles closed from damage. They work equally well in hard or soft water, and are naturally derived and biodegradable.