In 1916 the first industrial detergent was made. In 1970, scientists discovered phosphate. Soon after, scientists discovered that phosphate polluted the water. So phosphate detergent is banned. In the U.S.A. we use biodegradable detergents.
Biodegradable detergents are capable of being decomposed naturally.
Detergents work like this, the material must first become wet. Then detergent removes the film from the material. Finally, it holds in water until the film is rinsed away. Colorimeters are used to determine the color of different types of object compared to pure white. I used the colorimeter to measure the fabric colors after they have been washed and stained.