Material of Construction of cellulose pad
The material of construction for cellulose cooling pads is specifically engineered to maximize evaporative efficiency while maintaining structural integrity.
The primary material is cellulose, but it is never used in its raw form. It is combined with other materials and treated to create a functional and durable product.
Here is a detailed breakdown of the materials and their roles:
1. Primary Material: Cellulose Fibers
- Source: The cellulose typically comes from aspens or other hardwoods that are known for their long, absorbent fibers. These woods are chosen for their high porosity and excellent natural wicking ability.
- Form: The wood is processed into a pulp, which is then formed into sheets.
2. Binding Agents (Resins)Purpose: Raw cellulose paper would disintegrate quickly when wet. To make it rigid and
- durable, special water-resistant resins are used as binders.
- Type: These are typically phenol-formaldehyde or urea-formaldehyde resins. They are saturated into the cellulose paper and then cured (heated) to create a strong, rigid, and water-resistant bond between the fibers. This process is crucial for preventing the pad from turning to mush when saturated with water.
3. Corrugation and Lamination
- Process: The resin-impregnated cellulose paper is then passed through machines that give it its characteristic fluted or corrugated shape.
- Lamination: Multiple layers of this corrugated sheet are laminated together in a cross-fluted pattern (where the flutes of one layer are at an angle to the next). This creates the thousands of small, intersecting air and water channels that maximize surface area for evaporation.
4. Chemical Treatments (Additives)
To enhance performance and longevity, the cellulose material is often treated with additional chemicals:
- Wetting Agents: These are surfactants that reduce the surface tension of water, helping it to spread evenly and soak into the cellulose fibers more completely. This ensures the entire pad surface is wet for maximum efficiency.
- Anti-Rot and Fungicidal Additives: Since cellulose is an organic material, it can be a food source for algae, mold, and mildew. These additives inhibit biological growth, extending the pad’s life and maintaining hygiene.
- Fire Retardants: Some pads are treated with salts or other compounds to make them less combustible and self-extinguishing for improved safety.