How sanitary pads are made

A disposable pad is a sandwich, and its middle layer holds a powder that turns to gel when wet.

stations: 7
things upstream: 38
raw sources: 10
steps from the ground: 8

The short version

A disposable menstrual pad is layered: an absorbent core between a soft nonwoven top sheet and a liquid-proof polyethylene film backing. The core is ground fluff pulp wrapped in tissue, often with superabsorbent polymer powder that gels when wet. Hot melt seals the layers, a glue strip and release paper go on the back, and the strip is cut and wrapped.

Grind the pulp

Sheets of fluff pulp, made from wood, are ground up into loose fibers. The fluffed fiber is what gives the core its bulk and wicking.

Goes in
Wood pulp
Form the absorbent mat

The fibers are laid into a mat, with superabsorbent polymer added as an extra absorbent. Tissue is spread above and below it to hold the mat together.

Goes in
Superabsorbent polymer Paper
Lay the top sheet

A thermally bonded nonwoven fabric covers the core on the side that touches the body. It passes fluid quickly to the center and stays soft.

Goes in
Polypropylene
Wrap in film

A very thin polyethylene film goes on the outer side to stop leaks.

Goes in
Polyethylene
Seal and emboss

Hot melt adhesive and embossing seal the layers together around the edge of each pad.

Goes in
Adhesive
Apply the glue strip

A pressure-sensitive hot melt is laid on the outside of the backing so the pad stays on the underwear, and release paper covers it until use.

Goes in
Adhesive Paper
Cut and wrap

The layered strip is cut into pad shapes and each pad is folded and wrapped for sale.

End of the lineSanitary pad

Worth repeating

Disposable pads first appeared commercially around 1880 with the Southall sisters' pad.
Johnson & Johnson's Lister's Towels, from 1888, were the first commercial American disposable napkins.
Early pads were up to two centimeters thick, and leaks were a major problem.