What Glue Is Used in Sanitary Napkins? Hot-Melt Adhesives Explained

Sanitary napkins use hot-melt adhesives: solvent-free glues that are melted, applied in thin lines or sprays, and set as they cool. Most are made from synthetic rubber, such as SBS or SIS block copolymers, or from polyolefins, blended with tackifying resins and oil. Pads use them for three jobs:

• Construction: bonding the layers together.
• Positioning: holding the pad to underwear.
• Core stabilization: keeping the absorbent core in place.

What Is Hot-Melt Adhesive?

Hot-melt adhesive is a thermoplastic glue that is solid at room temperature, becomes liquid when heated, and bonds as it cools. Hygiene production lines melt it in heated tanks and apply it through nozzles as fine lines, spirals, or sprays, at the full speed of the line.

Because it contains no water or solvent, hot-melt does not need drying time and does not release solvent vapors during production. A typical hygiene hot-melt is a blend of three groups of ingredients:

• Polymer backbone: synthetic rubbers such as styrene-butadiene-styrene (SBS) or styrene-isoprene-styrene (SIS), or polyolefins. This gives strength and elasticity.
• Tackifying resin: makes the adhesive sticky.
• Oil or plasticizer: controls softness and how easily the glue flows.

Pressure-sensitive hot-melts based on styrene block copolymers have been used for pad positioning for decades. A typical example is described in US Patent 4,704,110 for hot-melt pressure-sensitive positioning adhesives.

Where Is Glue Used Inside a Sanitary Pad?

Glue is used in three places inside a sanitary pad, and each needs a different type of adhesive. Henkel, a major supplier of hygiene adhesives, groups its feminine care adhesives into the same three applications:

The release paper over the positioning adhesive is usually silicone-coated, so it lifts away without pulling the glue off. EDANA lists adhesives and release liner as standard parts of a pad in its overview of menstrual products composition. For the full layer structure, see our guide to what a sanitary napkin is made of.

What Makes a Good Positioning Adhesive?

A good positioning adhesive holds the pad firmly in place for hours, then peels off underwear cleanly without leaving residue or pulling fibers. It must balance two opposing goals: strong enough grip to stop shifting, but low enough to release without damage.

• Initial tack: the pad grips as soon as it is pressed onto underwear.
• Peel strength: the bond is high enough to stop shifting during movement and sitting.
• Clean release: no glue transfers to fabric and no fibers are pulled out.
• Fabric range: it works on cotton, synthetic, lace, and seamless underwear.
• Body-temperature stability: it does not soften too much and smear when warm.
• Breathability: the adhesive pattern on wings and backsheet still lets moisture vapor escape.

The adhesive pattern matters as much as the formula. Several narrow strips or a patterned coat can hold as well as a solid band while using less glue, peeling more cleanly, and keeping the backsheet breathable.

Why Does Construction Adhesive Matter?

Construction adhesive decides whether a pad stays in one piece during wear. If layers separate, the pad bunches, the core moves, and fluid finds a path to the edges, which leads to leaks.

The amount of construction glue is a trade-off. Too little and layers delaminate; too much and the pad turns stiff, less breathable, and less comfortable. Manufacturers control this with the adhesive add-on, meaning grams of glue per square meter, and with spray patterns that bond the layers without forming a solid film.

What Problems Does Bad Adhesive Cause?

Bad adhesive causes some of the most common sanitary pad complaints, and each one points to a specific adhesive property:

Adhesive problems are easy to miss in a quick sample check because they only appear during wear. That is why user trials matter. Our sanitary pad manufacturer checklist explains how to test samples before ordering.

Is the Glue in Sanitary Pads Safe?

The glue in sanitary pads sits inside the product or on the side facing the underwear, so it does not normally touch the skin. Like every pad material, it is covered by the chemical rules of the market where the pad is sold.

In the EU, chemical substances in products fall under REACH, and brands commonly ask suppliers for REACH test reports on the finished pad. A brand should also ask its manufacturer which adhesive supplier and grade is used, and for that supplier’s safety documentation. Low-odor grades are worth specifying, because users notice a glue smell as soon as they open the wrapper.

How Should Brands Specify Adhesive With a Manufacturer?

Brands should treat adhesive as a named part of the product specification, not a factory detail. Agree on these points in writing before mass production:

1. Adhesive supplier and grade for construction, positioning, and wings.
2. Peel strength range on a standard test fabric, measured by a defined method.
3. Tests on your customers’ fabrics: cotton, synthetic, and seamless underwear.
4. Aging and climate: how the adhesive performs after storage, and in hot or humid markets.
5. Odor: a check when the wrapper is opened.
6. No change without notice: the factory must tell you before switching adhesive supplier or grade.

The last point is important. A quiet switch to a cheaper adhesive is a common cause of sudden complaints about shifting or residue.

How Does TianZheng Use Adhesives?

TianZheng uses Henkel adhesive in its OEM sanitary pads. It is chosen for secure, no-shift placement and low odor, and paired with odor-neutralizing technology. The adhesive works together with the pad’s other published specifications:

• A 100% SAP core
• A 3D micro-embossed topsheet produced in-house
• A microporous breathable backsheet
• Secure wings

For private label projects, adhesive placement can be matched to pad length and wing design across day pads, night pads, and panty liners. See the full specification on our sanitary pad manufacturing page.

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