How disposable diapers are made

A disposable diaper is a stack of thin layers built around a core that soaks up urine and locks it in.

stations: 6
things upstream: 36
raw sources: 9
steps from the ground: 8

The short version

A disposable diaper is assembled in layers on a fast moving line. A core of air-laid paper fluff mixed with superabsorbent polymer is laid between a soft nonwoven layer on the skin side and a breathable polyethylene film on the outside. Elastics and tapes are added, and the web is cut and folded.

Fluff the core

Wood pulp is shredded into fluff and blended with superabsorbent polymer granules, then laid down as an absorbent pad. The superabsorbent grabs the liquid and keeps it from coming back out.

Goes in
Wood pulp Superabsorbent polymer
Cover the skin side

A layer of soft nonwoven fabric is laid next to the skin, with a distribution layer beneath that spreads wetness to the core. The nonwoven can be made of polypropylene.

Goes in
Polypropylene
Seal the outer shell

The outside is a breathable polyethylene film, or a film and nonwoven composite. It keeps wetness and soil from passing through.

Goes in
Polyethylene Adhesive
Add elastics and tapes

Elasticized fabric is attached around the legs and waist. Adhesive or mechanical fastening tapes go on the back, and some can be refastened.

Goes in
Adhesive
Cut and fold

The continuous web is cut into single diapers, which are folded into compact shape.
Count and bag

Diapers are counted by machine into stacks and sealed in plastic bags or boxes.

End of the lineDisposable diaper

Worth repeating

In 1946 Marion Donovan used a shower curtain from her bathroom to create the Boater, a diaper cover made from army surplus nylon parachute cloth.
Procter & Gamble began researching disposable diapers in 1956.
More than US$9 billion is spent on disposable diapers in North America each year.