What types of sponges are used in industrial production?

A wood pulp cotton rag manufacturer discusses the types of sponges used in industrial production. Many types of sponges are used in industrial production, including foamed cotton, memory foam, molded cotton, and rubberized cotton.
Recycled Cotton: Recycled cotton is made from waste cotton, industrial scraps, and textile factory fabric scraps and yarn ends. In particular, the raw materials may contain waste medical cotton, therefore, recycled cotton can be harmful to human health. Storing recycled cotton and civilian cotton together can easily cause pollution. High-quality cotton wadding generally has a soft color, appearing white or milky white. The fibers are fluffy and uniform, with a soft feel and good elasticity. Recycled cotton made from old cotton, due to sulfur bleaching or washing with laundry detergent, has an odor, while recycled cotton made from clothing waste will have a medicinal or musty smell. Recycled cotton itself can be produced, but it can only be used for industrial and agricultural insulation in greenhouses and other similar facilities, not for everyday use. For industrial and agricultural insulation, black or white spots on recycled cotton are irrelevant. Recycled cotton is made from waste materials from fibrous industries. Because it has undergone multiple processes such as chemical bleaching and dyeing, it is harmful to the human body. Therefore, the state does not allow it to be used in people's cotton clothing and quilts or in places that come into direct contact with the human body.

Foamed cotton is a material made by foaming polyether, similar to leavened bread. It can be foamed mechanically or manually by surrounding the foam with wooden boards. The foamed cotton resembles a large square loaf of bread. It is then sliced using a slicing machine to achieve different thicknesses, and its firmness can be adjusted. Seat foam typically uses a density of 25-28 kg/m³, while other types use 20-22 kg/m³. While the firmness and density of the foam are directly related, they are also influenced by different additive formulations. Therefore, the industry categorizes foams as high-elasticity, gray-super-elastic, black-gray-super-elastic, and soft. When designing and using foams, a reasonable and scientific combination should be made according to different shapes and structures. Generally, different elasticity and density foams are used in the upper, middle, and lower sections. One type of foam is called fire-retardant cotton (flame-retardant cotton). This is actually foamed before adding fire retardants, such as chlorine and bromine, to the material formulation. This allows the foam to produce dense smoke when it catches fire, thus acting as a flame retardant.
Rubber foam is a type of sponge made primarily from natural latex. It possesses rubber-like properties, good elasticity and resilience, and does not deform. However, it is expensive, costing 3-4 times more than regular foam.
Shaped foam is made from polyurethane material mixed with foaming agents and other additives. It is pressed into simple molds and heated to create different shapes. It is suitable for swivel chair and sofa cushions, backrests, and in some cases, armrests. Currently, it uses a density of 55#-60# material, and its elasticity largely meets national standards. The elasticity and hardness of the foam can be adjusted depending on the part of the product. Generally, seat cushions are harder and denser, backrest cushions are less so, and backrest cushions are softer.