PP cotton, commonly known as doll cotton and hollow cotton, also known as filling cotton, is made of polypropylene fiber as artificial chemical fiber. Polypropylene fiber is (the density of plastic is relatively light, and it should be noted that polypropylene fiber is not confused with polyester fiber). From the production process, there are mainly two kinds: ordinary fiber and hollow fiber. This product has good resilience, smooth feel, low price and good warmth retention, and is widely used in toy filling and clothing.

PP cotton can be divided into two-dimensional PP cotton and three-dimensional PP cotton. Three-dimensional pp cotton is a kind of high-grade fiber cotton, and its raw material is better than two-dimensional PP cotton. Hollow fiber is used (the good price is around 15000, the common raw material is around 13000, and there are some below this price, but the raw material is too poor to achieve ideal rebound effect.