High-Density vs Low-Density PBT Bristles: What's the Real Difference?

🔧 Test 1: Wear Resistance

Method: Reciprocating friction under 1000g load for 10,000 cycles. Measure wear mass.

Result: High-density: 0.23 mg wear | Low-density: 0.61 mg wear

💡 Conclusion: High-density is 2.65x more wear-resistant than low-density.

🔄 Test 2: Elastic Recovery

Method: Bend 90°, hold for 1 hour. Release and measure residual angle after 5 seconds.

Result: High-density: Fully recovered | Low-density: ~8° residual

💡 Conclusion: High-density recovers faster and more completely — low-density tends to "bend over".

⚠️ Test 3: Flex Fatigue

Method: Repeated bending at 60°, 2Hz. Record number of cycles until breakage.

Result: High-density: >150,000 cycles (no break) | Low-density: ~72,000 cycles

💡 Conclusion: High-density has over 2x fatigue life of low-density.

🧩 Test 4: Feel & Cost

• Feel: High-density: firm, tactile, with structure | Low-density: soft, lacks support
• Cost: High-density raw material cost ≈ 2–3% higher, but lifespan increased several times → extremely high cost-performance ratio