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Sanitary Pad Raw Material Composition and Properties

Sanitary pads are essential hygiene products used by millions of women worldwide. The effectiveness and comfort of these products depend largely on the raw materials used in their production. Understanding the composition and properties of these materials is crucial for manufacturers and consumers alike. This article delves into the key raw materials used in sanitary pads, their functions, and their properties.

1. Top Sheet (Cover Stock)

The top sheet is the layer that comes into direct contact with the skin. It plays a vital role in providing comfort and dryness. The most common materials used for the top sheet include:

• Nonwoven Polypropylene: This material is soft, breathable, and allows for quick liquid penetration while keeping the surface dry.
• Perforated Film: Some pads use a thin plastic film with tiny holes to enhance dryness and prevent backflow.

Properties of the top sheet include high absorbency, softness, and hypoallergenic qualities to prevent skin irritation.

2. Absorbent Core

The absorbent core is the heart of the sanitary pad, responsible for retaining menstrual fluid. It typically consists of:

• Fluff Pulp: Made from wood pulp, this material is highly absorbent and biodegradable.
• Superabsorbent Polymers (SAP): These are synthetic materials that can absorb and retain large amounts of liquid relative to their size.

The combination of fluff pulp and SAP ensures maximum absorbency while maintaining a thin and comfortable pad.

3. Back Sheet

The back sheet is the bottom layer of the pad, designed to prevent leaks and provide a barrier against moisture. Common materials include:

• Polyethylene Film: This plastic film is waterproof and prevents leaks.
• Breathable Microporous Film: Some premium pads use this material to allow air circulation while still preventing leaks.

Properties of the back sheet include waterproofing, flexibility, and durability to withstand movement.

4. Adhesive

Adhesives are used to keep the pad in place on the underwear. The most common types are:

• Pressure-Sensitive Adhesive: This type of adhesive sticks firmly to fabric but can be removed without leaving residue.
• Hot Melt Adhesive: Used in the manufacturing process to bond different layers together.

Adhesives must be strong enough to keep the pad in place but gentle enough to avoid damaging clothing.

5. Release Paper

Release paper covers the adhesive before use. It is typically made from:

• Silicone-Coated Paper: This material allows for easy removal of the paper without affecting the adhesive.

The release paper must be easy to peel off and should not leave any residue.

6. Fragrance and Additives

Some sanitary pads include fragrances or additives to mask odors or provide additional comfort. These may include:

• Natural or Synthetic Fragrances: Used to provide a pleasant scent.
• Aloe Vera or Chamomile: Added to soothe the skin and