Sanitary Napkins Raw Material Composition and Properties

# Sanitary Napkins Raw Material Composition and Properties

Sanitary napkins, also known as sanitary pads, are essential hygiene products used by women during menstruation. 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 napkins.

## 1. Absorbent Core

The absorbent core is the most critical component of a sanitary napkin. It is responsible for absorbing menstrual fluid and keeping the user dry. 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 blended with superabsorbent polymers (SAP) to enhance its capacity to retain fluids.
– **Superabsorbent Polymers (SAP)**: SAPs are synthetic materials that can absorb and retain large amounts of liquid relative to their mass. They are highly effective in preventing leakage and ensuring long-lasting dryness.

## 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 absorption of menstrual fluid. Common materials used for the top sheet include:

– **Nonwoven Fabrics**: These are made from synthetic fibers such as polypropylene or polyethylene. They are designed to be soft, breathable, and quick-drying.
– **Perforated Film**: Some sanitary napkins use a perforated plastic film as the top sheet. This material is highly effective in preventing backflow and keeping the surface dry.

## 3. Back Sheet

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

– **Polyethylene Film**: This is a common material used for the back sheet due to its waterproof properties. It is lightweight, flexible, and provides an effective barrier against leaks.
– **Breathable Microporous Film**: Some high-end sanitary napkins use breathable films that allow air to pass through while still preventing liquid leakage. This enhances comfort by reducing moisture buildup.

## 4. Adhesive

Adhesives are used to secure the sanitary napkin in place within the underwear. The adhesive must be strong enough to hold the pad in place but gentle enough to avoid causing irritation or leaving residue. 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 a strong bond and are commonly used in sanitary napkin production.
– **Pressure-Sensitive Adhesives**: These adhesives form a bond when pressure is applied. They are easy to apply and remove, making them ideal for use in sanitary napkins.

## 5. Release Paper

Release paper is used to cover the adhesive before the sanitary napkin is used. It is typically made from silicone-coated paper or film, which allows for easy removal without damaging the adhesive.

## Properties of Sanitary Napkin Raw Materials

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

– **Absorbency**: High absorbency is crucial for preventing leakage and maintaining dryness.
– **Softness**: The materials must be soft to avoid irritation and ensure comfort during use.
– **Breathability**: Breathable materials help reduce moisture buildup and prevent discomfort.
– **Flexibility**: The materials should be flexible to conform to the body’s shape and provide a secure fit.
– **Biodegradability**: With increasing environmental concerns, biodegradable materials are becoming more popular in sanitary napkin production.

In conclusion, the raw materials used in sanitary napkins play a vital role in determining the product’s performance, comfort, and safety. By understanding the composition and properties of these materials, manufacturers can produce high-quality sanitary napkins that meet the needs of users