Sanitary Napkins Raw Material Composition and Properties

# Sanitary Napkins Raw Material Composition and Properties

Sanitary napkins are essential personal hygiene products used by women during menstruation. Understanding the raw materials used in their production is crucial for ensuring comfort, safety, and effectiveness. This article delves into the composition and properties of the primary materials used in sanitary napkins.

## 1. Absorbent Core

The absorbent core is the most critical component of a sanitary napkin. It is responsible for absorbing and retaining menstrual fluid. The core 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. It is derived from softwood trees and processed to create a fluffy, fibrous material. The properties of fluff pulp include:

– High absorbency
– Soft texture
– Biodegradability

### Superabsorbent Polymers (SAP)

SAPs are synthetic materials that can absorb and retain large amounts of liquid relative to their mass. They are often used in conjunction with fluff pulp to enhance the absorbency of the core. Key properties of SAPs include:

– High liquid retention capacity
– Gel formation upon absorption
– Non-toxicity

## 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 such as polypropylene or polyester. They are chosen for their:

– Softness
– Breathability
– Moisture-wicking properties

### Perforated Films

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

– Smooth texture
– Quick-drying surface
– Durability

## 3. Back Sheet

The back sheet is the outermost layer of the sanitary napkin, designed to prevent leakage. It is typically made from:

### Polyethylene Film

Polyethylene film is a common material used for the back sheet due to its:

– Waterproof properties
– Flexibility
– Lightweight nature

### Breathable Microporous Films

Breathable microporous films are advanced materials that allow air to pass through while blocking liquids. They provide:

– Enhanced comfort
– Reduced risk of skin irritation
– Improved breathability

## 4. Adhesives

Adhesives are used to secure the sanitary napkin to the underwear. They are typically pressure-sensitive adhesives that are:

– Hypoallergenic
– Strong yet removable
– Non-irritating to the skin

## 5. Release Paper

Release paper is used to cover the adhesive before use. It is usually made from silicone-coated paper or film, offering:

– Easy removal
– Protection of the adhesive
– Smooth surface

## Conclusion

The composition and properties of raw materials used in sanitary napkins play a vital role in their performance and user comfort. From the absorbent core to the top sheet and back sheet, each component is carefully selected to ensure optimal functionality. Understanding these materials helps in making informed choices and appreciating the technology behind everyday hygiene products.