BOV (Bag-on-Valve) Aerosol Technology
Bag-on-Valve (BOV) is the fastest-growing segment in aerosol packaging. Unlike traditional aerosol where propellant mixes with the product, BOV separates them — the product sits in a sealed inner bag, and compressed air or nitrogen between the bag and can wall provides dispensing pressure. This fundamental difference creates unique production requirements and market advantages.
How BOV Differs from Traditional Aerosol
| Feature | Traditional Aerosol | BOV |
|---|---|---|
| Propellant-Product Contact | Mixed — propellant and product in same chamber | Separated — product in bag, propellant outside bag |
| Propellant Type | LPG, DME (liquefied gases) | Compressed air or N₂ |
| Spray Direction | Upright only (dip tube) | 360° — works upside down |
| Product Purity | Contains propellant | 100% pure product |
| Fill Process | Liquid fill → valve → gas fill | Gas under cap → liquid fill → seal |
| Per-Can Cost | Lower | ~20-30% higher (bag + valve cost) |
The BOV Filling Process
BOV filling follows a different sequence than traditional aerosol:
- Can Loading: Empty can with BOV valve assembly pre-inserted
- Under-Cap Gassing: Compressed air or N₂ is injected under the valve cap, pressurizing the space between the bag and can wall
- Liquid Filling: Product is injected through the valve stem into the inner bag
- Sealing: The valve is crimped to create a permanent seal
This sequence requires dedicated BOV equipment — standard aerosol fillers cannot perform under-cap gassing and through-stem filling simultaneously.
BOV Equipment Range
Semi-Automatic BOV Fillers
| Model | Capacity | Speed | Best For |
|---|---|---|---|
| FD9605 (Type A — Basic) | 30-500 ml | 500-800 cans/h | R&D, startups, small batches |
| FD9606 (Type B) | 30-500 ml | 600-1,000 cans/h | Small-scale production |
| FD9607 (Type C) | 30-500 ml | 800-1,200 cans/h | Medium production |
| FD9608 (Type D — High-Capacity) | 30-600 ml | 1,000-1,500 cans/h | Highest semi-auto BOV throughput |
Fully Automatic BOV Lines
| Model | Speed | Configuration |
|---|---|---|
| FD9901 (Type A — Basic) | 20-30 cans/min | Touchscreen + PLC; gassing + sealing + filling |
| FD9902 (Type B) | 30-40 cans/min | 2 gassing/sealing machines + 2 fillers; servo control |
| FD9903 (Type C) | 25-35 cans/min | Sample-can positioning for quick size change |
| FD9904 (Type D — High-Speed) | 40-60 cans/min | 2-can simultaneous feed; 6 fillers; premium components |
Cost Comparison: BOV vs. Traditional
Scenario: Personal care spray, 100 ml, 500,000 cans/year
| Cost Item | Traditional | BOV |
|---|---|---|
| Can + Valve (per unit) | $0.12-0.18 | $0.20-0.28 |
| Propellant Cost (per can) | ~$0.03 (LPG) | ~$0.01 (compressed air/N₂) |
| Packaging Cost Difference | — | ~$0.06-0.10 more per can |
| Annual Packaging Premium | — | $30,000-50,000 |
This premium is typically recovered through higher retail pricing — BOV products command 15-30% price premiums in personal care and pharmaceutical markets due to perceived quality and 360° spray convenience.
Market Applications
- Cosmetics: Sunscreens, facial mists, thermal water sprays, tanning products
- Pharmaceuticals: Wound care sprays, nasal saline, topical analgesics, oxygen-sensitive drugs
- Food: Cooking oils, whipped cream, cheese spreads, vinegar sprays
- Personal Care: Deodorants, dry shampoos, body sprays with natural formulations
- Industrial: High-purity lubricants, electronic contact cleaners, adhesives
Frequently Asked Questions
Can I convert my existing line to handle BOV?
No. BOV filling uses a fundamentally different process (under-cap gassing + through-stem filling) that standard equipment cannot perform. You need dedicated BOV equipment. However, you can run traditional and BOV lines in the same facility — many manufacturers do.
Is BOV worth the extra cost?
For the right products, yes. BOV enables: preservative-free claims (oxygen never contacts the product), 100% product evacuation (no waste for the consumer), 360° spray (superior user experience), and premium retail positioning. If your target market values these attributes and will pay a premium, BOV is a strong differentiator. If you compete on price in a commoditized category, traditional aerosol is more cost-effective.
What propellant do BOV systems use?
Compressed air or nitrogen (N₂). These are non-flammable, low-cost, and environmentally clean. The propellant never contacts the product, so there are no compatibility concerns. The compressed gas simply squeezes the inner bag to push product out.