1. Does gel really cool things down? How long does the effect last? How much better is it than regular memory foam?
Gel lowers the surface temperature through heat conduction and absorption (tests show 1-3 degrees C lower), but the effect is limited: surface-sprayed or low-content gel only lasts 30-60 minutes, while genuinely in-matrix gel infusion or PCM versions last longer. Low-priced products are often questioned as being pure marketing.
2. How do I choose density and ILD (firmness), and what is recommended for different applications?
Density is commonly 40-60 kg/m3 (about 2.5-4+ PCF); higher density is more durable and supportive.
ILD (Indentation Load Deflection) determines firmness: pillows use a lower ILD, mattresses and seat cushions use a medium to high ILD.
3. Will it sag quickly? What is its service life? Is it pure material or filler-extended?
Premium pure material (no cheap fillers) combined with high density can last 7-10 years, and the rebound rate after roll packing and transport is usually required to be 95-98% or higher. Low-priced products with added fillers are the biggest problem area.
4. What gel infusion methods are available? Can it be customized?
Uniform micro-bead infusion, vortex mixing, surface gel coating, and PCM phase change materials.