# 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 heart of a sanitary pad, responsible for absorbing and retaining menstrual fluid. It is typically made from a combination of the following materials:

– Fluff Pulp: A highly absorbent material derived from wood pulp. It is soft, lightweight, and capable of holding a significant amount of liquid.
– Superabsorbent Polymers (SAP): These are synthetic materials that can absorb and retain large amounts of liquid relative to their own mass. SAP enhances the absorbency of the pad, preventing leakage.

## 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 penetration. Common materials used 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 Films: Some pads use a perforated plastic film as the top sheet, which allows for rapid liquid transfer to the absorbent core 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 Film: A thin, flexible plastic film that is impermeable to liquids. It is lightweight and provides an effective barrier against leaks.
– Breathable Films: These are microporous films that allow air and moisture vapor to pass through while blocking liquid. They enhance comfort by reducing heat and 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 types of adhesives used include:

– Hot Melt Adhesives: These are thermoplastic adhesives that are applied in a molten state and solidify upon cooling. They provide strong, durable bonds.
– Pressure-Sensitive Adhesives: These adhesives are tacky at room temperature and form a bond when pressure is applied. They are used for attaching the pad to the underwear.

## 5. Release Paper

Release paper is used to cover the adhesive on the back of the pad before use. It is typically made from:

– Silicone-Coated Paper: This paper is coated with a silicone release agent that allows it to be easily peeled away from the adhesive without leaving residue.

## Properties of Sanitary Pad Materials

The materials used in sanitary pads must possess several key properties to ensure effectiveness and user comfort:

– Absorbency: High absorbency is crucial for preventing leaks and maintaining dryness.
– Softness: The materials must be soft to prevent irritation and ensure comfort during use.
– Breathability: Good air circulation helps to reduce heat and moisture buildup, enhancing comfort.
– Flexibility: The pad should be flexible to conform to the body’s shape and movements.
– Hypoallergenic: Materials should be non-irritating and safe for sensitive skin.

In conclusion, the raw materials used in sanitary pads are carefully selected to provide optimal absorbency, comfort, and protection. Understanding these materials and their properties helps in appreciating the engineering and design that goes into creating an essential product for women’s health and hygiene.