Common Materials Used in Sanitary Napkins

Sanitary napkins, also known as sanitary pads or menstrual pads, consist of multiple layers, each serving a specific functional purpose. The primary materials used include:

1. **Top Sheet (Acquisition Layer)**
Typically made from non-woven polypropylene or polyester fabric, sometimes blended with rayon or viscose. This layer is soft, breathable, and designed to rapidly absorb fluid while maintaining dryness against the skin. It may be treated with surfactants to enhance wettability.

2. **Distribution Layer**
Often composed of airlaid paper, cellulose fluff pulp, or synthetic fibers like PET or PE/PP bicomponent fibers. This middle layer disperses liquid evenly across the pad to maximize absorption efficiency and prevent pooling.

3. **Absorbent Core**
The main absorptive component usually combines wood pulp (bleached or unbleached), superabsorbent polymers (SAPs)—commonly sodium polyacrylate—and occasionally cotton or bamboo-derived cellulose. SAPs can absorb dozens of times their weight in fluid and lock it away through gel formation.

4. **Back Sheet (Barrier Layer)**
A thin, waterproof film—typically made from polyethylene (PE) or laminated polyolefin—to prevent leakage. Some eco-friendly variants use biodegradable films derived from cornstarch or PBAT blends

5. **Adhesive System**
Pressure-sensitive adhesives, often acrylic-based or hot-melt thermoplastic glues, secure the pad to underwear. Adhesive strips may be covered by removable silicone-coated paper liners.

6. **Additional Components**
Wings (if present) are extensions of the back sheet bonded with elasticized nonwovens for better fit; odor-control agents such as activated carbon or zinc compounds may be added; fragrance-free options omit perfumes entirely.

Manufacturers increasingly prioritize hypoallergenic, chlorine-free bleaching processes, dermatologically tested surfaces, and sustainable alternatives—including organic cotton topsheets, compostable cores, and reduced-plastic designs—to meet evolving health and environmental standards.