Most foam mattresses are made of slow rebound foam. Slow rebound foam mattresses have excellent rebound properties, greatly reducing the need for tossing and turning in bed, thus improving sleep quality. The difference between slow rebound memory foam and traditional foam is that slow rebound memory foam is a special material unlike any other foam encountered before. Slow rebound memory foam is a material that can deform according to changes in body temperature. When pressure is applied to a slow rebound foam surface, it does not rebound until all the pressure is evenly distributed. When the external pressure stops, it slowly returns to its original shape.
Sponge mattresses, along with spring mattresses, are commonly used modern mattress types, characterized by their lightness and comfort. Modern products mostly use slow rebound memory foam, which can deform according to body temperature and evenly distribute pressure, exhibiting differentiated rebound characteristics compared to traditional foam. This type of mattress improves comfort by conforming to the body's shape and minimizes disturbance when a partner tosses and turns. However, it may have issues such as insufficient lumbar support potentially leading to strain, and poor breathability affecting health. Regularly changing the position of the mattress is necessary to prevent sagging. There is adulteration in the market where stone powder is added to reduce costs. The quality can be identified by observing the uniformity of the pores, testing the extrusion rebound speed, and comparing the tensile strength.