Disposable diapers are made from a pad capable of absorbing moisture attached between nonwoven fabric in two layers designed to prevent any leakage. The bottom and top sheets of disposable diapers are made from waterproof plastic in order for the diaper to absorb for several times the weight in fluid. Then elastic garters are fitted around the edges to provide a close fit around the legs of baby.
The pad that is found n the middle of the diaper is made with synthetic polymer that is manufactured from fine particles of acrylic and another acrylic derivative that act like sponges for moisture absorption. The chemical compound enables the diaper to be absorbent without being to bulky or thick. When the pad gets weak, the tiny crystals within the polymer turn into gel. Wood pulp from pine trees is usually added with the polymer so it can create the fill material in the pad. The wood fibers would act like straws that can help suck up water.
Nonwoven fabric sheets will hold the absorbent diaper pad in place. It is made from plastic resins like polyester, nylon, polyethylene or polypropylene that is assembled by wet-laid or dry-laid process. The dry laid process is commonly use and it involves melting plastic resin. Then air pressure is applied to force the melted resin through the small holes. The fibers condense into a sheet when cooled. The heated rollers will flatten the fibers and bond these altogether. For the permeable top sheet, polypropylene is the material typically used. Though the back sheet appears like a cloth fabric, it is made from plastic. These sheets are produced first on roll as bolt of fabric and eventually cut into the proper width of diapers. The outer fabric coverings are manufactured often in different location.
Then the elastic bands are attached into the backing sheet using adhesive. It is done to help improve the diaper fit. Elastics are made from rubber, polyurethane foam or spandex. The backing sheet and absorbent pad are sent into conveyor. Once the top sheet is fed in place, the diaper is sealed either by heating or gluing. The adhesive mixture will be applied next to hot glue the materials together while it cools. Then adhesive tape is attached before cutting the roll in individual diapers for folding and packaging.