# Sanitary Pad Raw Material Composition and Properties

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

## Core Absorbent Material

The core of a sanitary pad is designed to absorb and retain menstrual fluid. The primary materials used in the core include:

– **Wood Pulp**: This is the most common absorbent material. It is highly absorbent and helps in quickly drawing moisture away from the body.
– **Super Absorbent Polymer (SAP)**: SAP is a synthetic material that can absorb many times its weight in liquid. It is often mixed with wood pulp to enhance the pad’s absorbency.

## Top Sheet

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

– **Nonwoven Fabric**: Made from synthetic fibers like polypropylene, nonwoven fabrics are soft, breathable, and allow for quick liquid penetration.
– **Perforated Film**: Some pads use a perforated plastic film as the top sheet, which is designed to feel dry even when wet.

## Back Sheet

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

– **Polyethylene Film**: This is a waterproof material that prevents menstrual fluid from leaking through the pad.
– **Breathable Microporous Film**: Some high-end pads use breathable films that allow air to circulate while still preventing leaks.

## Adhesive

To keep the pad in place, an adhesive is applied to the back sheet. The adhesive must be strong enough to hold the pad securely but gentle enough to be removed without causing skin irritation. Common adhesives include:

– **Hot Melt Adhesive**: This type of adhesive is applied in a molten state and solidifies upon cooling, providing a strong bond.
– **Pressure-Sensitive Adhesive**: This adhesive remains tacky at room temperature and bonds upon application of light pressure.

## Additional Components

Some sanitary pads include additional components for enhanced comfort and functionality:

– **Wings**: These are extensions on the sides of the pad that fold over the edges of underwear to provide extra security.
– **Fragrance**: Some pads are infused with a light fragrance to mask menstrual odor. However, fragrances can sometimes cause irritation for sensitive skin.
– **Moisturizers**: Certain pads include moisturizing agents like aloe vera to soothe the skin.

## Properties of Raw Materials

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

– **Absorbency**: The core materials must be highly absorbent to manage menstrual flow effectively.
– **Softness**: The top sheet should be soft and non-abrasive to prevent skin irritation.
– **Breathability**: The materials should allow air to circulate to reduce the risk of bacterial growth and discomfort.
– **Leakage Protection**: The back sheet must be impermeable to prevent leaks.
– **Hypoallergenic**: All materials should be hypoallergenic to minimize the risk of allergic reactions.

In conclusion, the raw materials used in sanitary pads are carefully selected to provide comfort, safety, and effectiveness. Understanding these materials and their properties can help consumers make informed choices about the products they use.