# Sanitary Pads Raw Material Composition and Properties

Sanitary pads are essential personal care products designed to provide comfort and hygiene during menstruation. Understanding the raw materials used in their production is crucial for evaluating their quality, safety, and environmental impact. This article explores 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, responsible for absorbing menstrual fluid. It is typically made from a combination of the following materials:

– **Wood Pulp**: A natural, biodegradable material that provides excellent absorbency. It is often blended with superabsorbent polymers (SAP) to enhance its capacity.
– **Superabsorbent Polymers (SAP)**: These synthetic materials can absorb and retain large amounts of liquid relative to their mass. SAPs are highly effective in preventing leakage and ensuring dryness.

## 2. Top Sheet

The top sheet is the layer that comes into direct contact with the skin. It must be soft, non-irritating, and allow for quick liquid penetration. Common materials include:

– **Nonwoven Fabrics**: Made from synthetic fibers like polypropylene or polyethylene, these fabrics are designed to be soft and breathable while facilitating rapid liquid transfer to the absorbent core.
– **Perforated Films**: These are thin plastic films with tiny holes that allow liquid to pass through while keeping the surface dry.

## 3. Back Sheet

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

– **Polyethylene (PE) Film**: A lightweight, waterproof material that is flexible and durable. It ensures that the pad remains leak-proof while being comfortable to wear.
– **Breathable Microporous Films**: These films allow air to pass through while blocking liquids, enhancing comfort by reducing moisture buildup.

## 4. Adhesive

Adhesives are used to secure the pad to the underwear. They must be strong enough to hold the pad in place but gentle enough to avoid damaging fabrics or causing skin irritation. Common types include:

– **Hot Melt Adhesives**: These are applied in a molten state and solidify upon cooling, providing a strong bond.
– **Pressure-Sensitive Adhesives**: These adhesives form a bond when pressure is applied, making them easy to use and reposition.

## 5. Release Paper

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

– **Silicone-Coated Paper**: This paper is treated with silicone to prevent the adhesive from sticking to it, allowing for easy removal when the pad is ready to be used.

## Properties of Sanitary Pad Materials

The materials used in sanitary pads must possess specific properties to ensure optimal performance and user comfort:

– **Absorbency**: The ability to quickly absorb and retain menstrual fluid is crucial for preventing leaks and maintaining dryness.
– **Softness**: Materials that come into contact with the skin must be soft and non-irritating to prevent discomfort or allergic reactions.
– **Breathability**: Breathable materials help reduce moisture buildup, minimizing the risk of skin irritation and odor.
– **Flexibility**: The pad should be flexible enough to conform to the body’s shape, ensuring a comfortable fit.
– **Biodegradability**: With increasing environmental concerns, there is a growing demand for biodegradable materials that reduce the ecological footprint of sanitary pads.

In conclusion, the raw materials used in sanitary pads play a vital role in determining their effectiveness, comfort, and environmental impact. By understanding the composition and properties of these materials, consumers can make informed choices and manufacturers can continue to innovate and improve their products.