Sanitary Napkins Raw Material Composition and Properties

# Sanitary Napkins Raw Material Composition and Properties

Sanitary napkins are essential personal care products designed to provide comfort and hygiene during menstruation. Understanding the raw materials used in their production is crucial for ensuring quality and safety. This article delves into the composition and properties of the primary materials used in sanitary napkins.

## 1. Absorbent Core

The absorbent core is the heart of a sanitary napkin, responsible for absorbing menstrual fluid. It is typically made from a blend of fluff pulp and superabsorbent polymers (SAP).

### Fluff Pulp

Fluff pulp is a type of wood pulp that is highly absorbent and soft. It is derived from softwood trees like pine and spruce. The properties of fluff pulp include:

– High absorbency
– Soft texture
– Biodegradability

### Superabsorbent Polymers (SAP)

Superabsorbent polymers are synthetic materials that can absorb and retain large amounts of liquid relative to their own mass. They are usually made from polyacrylate compounds. The properties of SAP include:

– High absorption capacity
– Gel formation upon absorption
– Non-biodegradability

## 2. Top Sheet

The top sheet is the layer that comes into direct contact with the skin. It is designed to be soft, comfortable, and quick-drying. Common materials used for the top sheet include:

### Nonwoven Fabrics

Nonwoven fabrics are made from synthetic fibers like polypropylene or polyethylene. They are chosen for their:

– Softness
– Breathability
– Quick-drying properties

### Perforated Films

Perforated films are thin plastic sheets with tiny holes that allow liquid to pass through while keeping the surface dry. They are known for their:

– Smooth texture
– Durability
– Water resistance

## 3. Back Sheet

The back sheet is the outermost layer of the sanitary napkin, designed to prevent leakage and provide a barrier against moisture. It is typically made from:

### Polyethylene Films

Polyethylene films are lightweight, flexible, and waterproof. They are commonly used for their:

– Moisture barrier properties
– Flexibility
– Durability

### Breathable Films

Breathable films are microporous materials that allow air to pass through while blocking liquids. They are valued for their:

– Breathability
– Comfort
– Leakage prevention

## 4. Adhesives

Adhesives are used to secure the sanitary napkin to the underwear. They are usually made from:

### Hot Melt Adhesives

Hot melt adhesives are thermoplastic materials that become sticky when heated. They are chosen for their:

– Strong adhesion
– Quick setting time
– Flexibility

### Pressure-Sensitive Adhesives

Pressure-sensitive adhesives are tacky at room temperature and adhere upon application of light pressure. They are known for their:

– Ease of use
– Reliable adhesion
– Comfort

## 5. Release Paper

Release paper is a protective layer that covers the adhesive before use. It is typically made from:

### Silicone-Coated Paper

Silicone-coated paper is treated with a silicone layer to prevent the adhesive from sticking to it. It is characterized by its:

– Non-stick properties
– Smooth surface
– Easy removal

## Conclusion

The raw materials used in sanitary napkins are carefully selected to ensure optimal performance, comfort, and safety. From the absorbent core to the release paper, each component plays a vital role in the overall functionality of the product. Understanding the composition and properties of these materials helps in appreciating the engineering behind this essential personal care item.