HL15 HL20 Hollow Glass Microsphere for Automotive Repair Putty and Paint
HL15 and HL20 Hollow Glass Microspheres are high-performance borosilicate hollow spherical inorganic fillers, specially developed for automotive repair putty, automotive refinish coatings and primer formulations.
These hollow microspheres feature low true density, good compressive strength, excellent flowability and uniform spherical shape. When incorporated into auto body putty, they effectively reduce the overall weight of the putty layer, lower material shrinkage during curing, minimize cracking and sagging problems. Meanwhile, they improve sanding performance, enabling easier polishing to acquire a smooth, flat substrate surface for subsequent topcoat spraying.
In automotive repair paint and primer systems, HL15 & HL20 microspheres deliver outstanding thermal insulation performance, enhance scratch resistance and dimensional stability of the coating film. Their stable chemical resistance helps improve the durability of finished paint layers.
HL15: Finer particle size, suitable for high-gloss fine putty and thin-layer refinish paint, brings ultra-smooth surface finish.
HL20: Slightly larger particle size, balances cost and filling efficiency, ideal for conventional automotive body repair putty.
Compared with conventional mineral fillers such as talc and calcium carbonate, HL series hollow glass microspheres significantly reduce coating density, save resin consumption, and reduce VOC emission. They are widely adopted in car body filler, repair putty, anti-corrosion primer and automotive thermal insulation coatings.
Chemical composition(%):
| SiO2 | 58-71 |
| Na2CO3 | 12-25 |
| B2O3 | 3-12 |
| Al2O3 | 0-10 |
| CaO | 0.2-1.0 |
| Fe2O3 | 0-0.5 |
| MgO | 0-0.05 |
Physical Index:
| True Density | 0.18-0.60g/cm3 |
| Bulk Density | 0.10-0.34g/cm3 |
| Crush Strength | 4-125Mpa/500-18000Psi |
| Survival | Min 90% |
| Flotation | Min 92% |
| Moisture | Max 0.5% |
| Particle Size | D50:20-70um |
| Max. Particle Size: | 200um |
| Melting Point | 1600°C |
Specifiction
| Spec. | True Density(g/cm3) | Bulk Density(g/cm3) | Compressive strength(Mpa/Psi) | D50(um) | D90(um) | Packing(Kgs) |
| HL15 | 0.13-0.17 | 0.08-0.09 | 4/500 | 65 | 120 | 8 |
| HL20 | 0.20-0.22 | 0.10-0.12 | 4/500 | 65 | 110 | 10 |
| HL25 | 0.24-0.27 | 0.13-0.15 | 5/750 | 65 | 100 | 12.5 |
| HL30 | 0.29-0.32 | 0.15-0.18 | 10/1500 | 55 | 85 | 15 |
| HL32 | 0.31-0.33 | 0.17-0.19 | 14/2000 | 45 | 80 | 15 |
| HL35 | 0.33-0.37 | 0.18-0.21 | 21/3000 | 40 | 70 | 15 |
| HL38 | 0.37-0.39 | 0.19-0.22 | 38/5500 | 40 | 65 | 20 |
| HL40 | 0.39-0.42 | 0.19-0.23 | 28/4000 | 40 | 70 | 20 |
| HL42 | 0.41-0.44 | 0.21-0.24 | 55/8000 | 40 | 60 | 20 |
| HL46 | 0.44-0.48 | 0.23-0.26 | 41/6000 | 40 | 70 | 22.5 |
| HL50 | 0.48-0.52 | 0.25-0.27 | 55/8000 | 40 | 60 | 25 |
| HL55 | 0.53-0.55 | 0.27-0.29 | 68/10000 | 40 | 60 | 25 |
| HL60 | 0.58-0.62 | 0.29-0.34 | 83/12000 | 40 | 65 | 30 |
| HL60S | 0.58-0.63 | 0.30-0.34 | 125/18000 | 35 | 55 | 30 |
| HS38 | 0.37-0.39 | 0.19-0.22 | 38/5500 | 30 | 50 | 20 |
| HM10 | 1.4-1.6 | 0.45-0.50 | 193/28000 | 5 | 10 | 30 |
| HM15 | 1.2-1.3 | 0.40-0.45 | 124/18000 | 7 | 15 | 30 |
| HM20 | 1.05-1.15 | 0.39-0.44 | 124/18000 | 9 | 20 | 25 |
| HM30 | 0.9-1.0 | 0.35-0.4 | 83/12000 | 14 | 30 | 25 |
| HS20 | 0.18-0.22 | 0.10-0.12 | 7/1000 | 60 | 90 | 10 |
| HS22 | 0.20-0.24 | 0.11-0.13 | 8/1200 | 45 | 70 | 10 |
| HS28 | 0.27-0.30 | 0.15-0.17 | 28/4000 | 45 | 65 | 15 |
| HS38 | 0.36-0.40 | 0.19-0.22 | 38/5500 | 30 | 50 | 20 |
| HS42 | 0.40-0.44 | 0.21-0.24 | 55/8000 | 25 | 40 | 20 |
| HS46 | 0.44-0.50 | 0.22-0.25 | 110/16000 | 20 | 30 | 22.5 |
| HS60 | 0.58-0.62 | 0.29-0.33 | 193/28000 | 16 | 25 | 30 |
| HS65 | 0.63-0.67 | 0.30-0.33 | 207/30000 | 13 | 20 | 32 |
| HS70 | 0.75-0.80 | 0.33-0.35 | 207/30000 | 10 | 15 | 35 |
