The Role of Release Paper in Sanitary Napkin Adhesive Performance

In the manufacture of sanitary napkins, the release paper—also known as the peel strip or backing paper—is a critical but often overlooked component. While it serves the simple function of protecting the adhesive layer before use, its design and quality profoundly influence the user experience. Two of the most common complaints—"adhesive residue left on underwear" and "release paper won't peel off"—are directly traceable to the properties of the release paper.

The Core Principle: How Release Paper Works

Release paper consists of a base substrate (usually kraft paper or a polymer film) coated with a thin layer of silicone oil. This silicone layer creates a non-stick surface that allows the pressure-sensitive adhesive (PSA) on the napkin to be temporarily held without bonding permanently. The key parameters governing this interaction are:

• Silicone coating weight: The amount of silicone applied per unit area.

• Release force: The force required to separate the release paper from the adhesive.

• Adhesive peel strength: The bond strength between the adhesive and the target surface (underwear fabric).

The relationship between these three parameters must be carefully balanced. If the release force is too high, the user cannot peel the paper off easily. If the release force is too low, the paper may detach prematurely or, more critically, the silicone may transfer to the adhesive, reducing the adhesive's ability to stick.