What material is the soundproof cotton?

Environmental protection polyester fiber soundproof cotton. ||||| 0/00% polyester fiber is an efficient sound-absorbing and heat-insulating material which is closest to nature, harmless to human body and pollution-free to the environment. Environmental-friendly polyester fiber is formed by laminating and hot-pressing bonding. Through the unique high-density tissue of the fiber, the sound can flow back in its cavity, effectively achieving the function of sound absorption and noise reduction. The biggest difference between it and traditional sound insulation materials is that it is environmentally friendly and harmless, has strong sound absorption ability, has no peculiar smell, is harmless to human body (does not itch), has uniform thickness, absorbs sound, has soft hand feeling, flat surface, good longitudinal and transverse strength and good sound absorption effect.