Automotive Front Dual-Density Polyurethane Seat Backrest Foam Core Assembly

This dual-hardness molded polyurethane seat backrest core is engineered for front-row passenger vehicle seats, integrated with an open-cell ventilation hole structure. Utilizing a graduated density design with a soft central lumbar contact zone and firm side bolsters, it delivers an optimal balance of plush initial contact and firm ergonomic back support. The high-density base layer and lateral bolsters lock driver posture in place during cornering while preventing long-term sagging. With enhanced fatigue resistance and vibration dampening compared to standard single-density foams, it alleviates lumbar fatigue and prevents permanent deformation over years of operation.

Parameter
Features

Surface Comfort Soft Zone	Density 32 to 38 kg/m3, Firmness 28 to 35 ILD (N) for ergonomic contouring and plush back support.
Bottom Load-Bearing Main Zone	Density 42 to 48 kg/m3, Firmness 40 to 50 ILD (N) for primary spinal support and long-term anti-sagging performance.
Side Bolster Support Zones	Density 50 to 55 kg/m3, Firmness 55 to 65 ILD (N) for lateral body positioning and posture shift prevention.
Resilience Rate	60% or higher (High resilience grade).
Compression Permanent Set	4% or lower (Tested at 50 degrees C for 22 hours under constant compression).
Tensile Strength	120 kPa or higher.
Tear Strength	2.0 N/mm or higher.
Safety & Environmental Standards
Flammability Rating	FMVSS 302 and GB 8410 Class B compliant for automotive interior safety.
Odor & VOC Level	Grade 3 or lower low-odor rating meeting vehicle eco-standards.

Key Features & Selling Points:
- Graduated Dual-Density Architecture: Features a soft center surface layer (28 to 35 ILD) combined with high-density structural zones (40 to 65 ILD) to support proper spinal alignment and immediate seating comfort.
- Lateral Side Bolster Support: High-density side wings (50 to 55 kg/m3) hold the upper body in position during turns, preventing side-to-side sliding.
- Anti-Sagging Long Life: Delivers a low compression set (4% or lower) and high tear resistance (2.0 N/mm or higher) to resist backrest sagging over extended drive times.
- Enhanced Shock & Vibration Dampening: Absorbs chassis vibrations to protect against back soreness and leg numbness during long-distance trips.
- Automotive Interior Safety Certified: Fully compliant with FMVSS 302 and GB 8410 Class B flame retardancy specifications with low-VOC Grade 3 or lower odor performance.