Understanding Carbon Black Nomenclature
Walk into any rubber factory or coatings plant, and you'll find carbon black being used somewhere in the process. But not all carbon black is created equal. The grade you choose directly impacts your product's mechanical properties, processing behavior, and final performance.
The "N" prefix means normal curing rate. The three-digit number indicates the ASTM classification based on particle size and surface area:
- N330 series: Fine particles (~30nm), high surface area
- N550 series: Medium particles (~40-50nm), moderate surface area
- N660 series: Coarse particles (~60-80nm), low surface area
Carbon Black N330: High-Performance Choice
Particle Size: ~30nm | Surface Area: 75-91 m²/g | Typical Loading: 40-60 phr
N330 delivers maximum reinforcement with excellent tensile strength, tear resistance, and superior abrasion resistance. It's the go-to grade for tire treads, high-stress rubber parts, conveyor belts, and industrial rollers.
Carbon Black N550: Balanced Workhorse
Particle Size: ~40-50nm | Surface Area: 39-49 m²/g | Typical Loading: 30-50 phr
N550 strikes a balance between reinforcement and processability. Popular for tire carcass and sidewalls, mechanical rubber goods, and molded rubber products requiring good surface finish.
Carbon Black N660: Cost-Effective Option
Particle Size: ~60-80nm | Surface Area: 20-30 m²/g | Typical Loading: 20-40 phr
N660 excels in applications needing good flex cracking resistance, low compound viscosity, and cost reduction. Ideal for EPDM roofing membranes, wire and cable jacketing, and rubber mats.
Quick Comparison
| Property | N330 | N550 | N660 |
|---|---|---|---|
| Particle Size | ~30nm | ~40-50nm | ~60-80nm |
| Reinforcement | Excellent | Good | Fair |
| Abrasion Resistance | Best | Moderate | Lowest |
| Processability | Harder | Easier | Easiest |
Quality Parameters
We provide detailed technical data sheets with every batch including CTAB surface area, DBP absorption, pellet hardness, and sieve residue. We supply carbon black in 20kg multi-wall paper bags, 500kg jumbo bags, and bulk pneumatic tanker trucks.
Technical Support from JBSR
Our technical team has hands-on experience with rubber compounding across tire, hose, belt, and molded goods sectors. We can help you select the optimal grade or grade blend, troubleshoot dispersion issues, and optimize loading levels.