Office Chair Sponge Filling

The sponge filling of office chairs is a core factor affecting the user experience. Common types include high-resilience foam sponge, molded cotton, regular sponge, and recycled cotton (primary blended cotton), with performance differences directly impacting support, comfort, and durability.

I. Common Sponge Types and Characteristics

1. High-Resilience Foam Sponge
   Support performance is determined by rebound speed and density distribution: if the density is too low or rebound is too slow, the hips are prone to sinking, leading to fatigue; if too hard, short-term comfort decreases. Its layering process affects long-term compression deformation rate, with high-quality products reducing the risk of sagging after 3-5 years.

2. Molded Cotton
   Made from polyurethane material, its density can be precisely adjusted and is considered the most stable and healthy option. Its advantage lies in uniform structure, maintaining shape over the long term, suitable for scenarios requiring continuous support (such as continuous office work for 8 hours or more).

3. Regular Sponge
   Soft but lacking in elasticity, comfortable for short-term use but prone to support loss due to compression deformation over the long term, suitable for budget-limited or low-frequency use scenarios.

4. Recycled Cotton (Primary Blended Cotton)
   Made from reprocessed scraps from recycling processes, some merchants claim it meets national standards. However, be wary of inferior products: "primary blended cotton" bonded with glue from shredded sponge is prone to releasing harmful substances and exhibits significant deformation over long-term use, which can be initially identified by disassembling to observe internal structure or checking for sagging after 1 year of use.

II. Key Technical Parameters and Usage Scenarios

• Layered Thickness and Density Gradient: The layered design of the filling better reflects actual support effectiveness than simple hardness values. For example, the lumbar support area should use density-gradient sponge to fit the body's curves and relieve prolonged sitting pressure.
• Frame and Sponge Synergy: Wooden frames may undergo slight deformation in humid environments, jointly affecting product lifespan with sponge filling. It is recommended to choose metal frames or wooden frames treated for moisture resistance to reduce performance degradation.
• Long-Term Compression Deformation Rate: High-density sponge reduces the risk of sagging after 3-5 years by optimizing molecular structure, suitable for high-frequency use scenarios; regular sponge or inferior recycled cotton may exhibit significant deformation within half a year to one year.

III. Purchase Recommendations

Prioritize molded cotton or high-density layered sponge, avoiding recycled cotton substituted in low-priced products. When purchasing, ask merchants for density parameters (e.g., 45D or above for high density) and observe whether the seat cushion edges are flat (inferior products are prone to depression due to uneven filling). After long-term use, if the seat cushion shows irreversible sagging or odor, replace the filling or the entire chair promptly.