Sanitary Pads Raw Material Composition and Properties

# Sanitary Pads Raw Material Composition and Properties

Sanitary pads are essential hygiene products used by millions of women worldwide. Understanding the raw materials used in their production is crucial for ensuring quality, comfort, and safety. This article delves into the composition and properties of the primary raw materials used in sanitary pads.

## 1. Absorbent Core

The absorbent core is the most critical component of a sanitary pad. It is responsible for absorbing and retaining menstrual fluid. The core is typically made from a combination of the following materials:

– **Wood Pulp**: Wood pulp is a natural, biodegradable material that provides excellent absorbency. It is often used in its fluff form, which is lightweight and highly absorbent.
– **Superabsorbent Polymers (SAP)**: SAPs are synthetic materials that can absorb and retain large amounts of liquid relative to their own mass. They are often used in conjunction with wood pulp to enhance the absorbency of the pad.

## 2. Top Sheet

The top sheet is the layer that comes into direct contact with the skin. It must be soft, comfortable, and allow for quick liquid transfer to the absorbent core. Common materials used for the top sheet include:

– **Nonwoven Fabrics**: These are made from synthetic fibers such as polypropylene or polyester. They are designed to be soft, breathable, and allow for rapid liquid penetration.
– **Perforated Films**: Some pads use perforated plastic films as the top sheet. These films are designed to be soft and allow for quick liquid transfer while keeping the surface dry.

## 3. Back Sheet

The back sheet is the outermost layer of the pad, designed to prevent leakage and provide a barrier against moisture. Materials used for the back sheet include:

– **Polyethylene Films**: These are thin, flexible plastic films that are impermeable to liquids. They are commonly used due to their effectiveness in preventing leaks.
– **Breathable Films**: Some pads use breathable back sheets that allow air to pass through while still preventing liquid leakage. These films enhance comfort by reducing moisture buildup.

## 4. Adhesives

Adhesives are used to secure the pad to the underwear and to bond the different layers of the pad together. The adhesives must be strong enough to hold the pad in place but gentle enough to avoid skin irritation. Common types of adhesives include:

– **Hot Melt Adhesives**: These are thermoplastic adhesives that are applied in a molten state and solidify upon cooling. They provide strong bonds and are commonly used in sanitary pad manufacturing.
– **Pressure-Sensitive Adhesives**: These adhesives form a bond when pressure is applied. They are often used for the adhesive strips that secure the pad to the underwear.

## 5. Release Paper

Release paper is used to cover the adhesive strips before the pad is used. It is typically made from silicone-coated paper or film, which allows for easy removal without leaving residue.

## Properties of Sanitary Pad Raw Materials

The raw materials used in sanitary pads must possess specific properties to ensure the product’s effectiveness and comfort:

– **Absorbency**: The materials must be able to absorb and retain menstrual fluid efficiently.
– **Softness**: The top sheet and other layers in contact with the skin must be soft to prevent irritation.
– **Breathability**: The materials should allow air to circulate to reduce moisture buildup and enhance comfort.
– **Leakage Prevention**: The back sheet and absorbent core must work together to prevent leaks.
– **Biodegradability**: Increasingly, there is a demand for biodegradable materials to reduce environmental impact.

In conclusion, the raw materials used in sanitary pads are carefully selected to provide a balance of absorbency, comfort, and safety. Understanding these materials and their properties helps in appreciating the complexity and innovation behind this everyday essential product.