walking into your warehouse to find insecticide cans leaking everywhere—this nightmare became reality for an Indonesian company in 2024, leading to a $910,000 dispute over rusted tinplate packaging. Tinplate cans dominate the aerosol market thanks to 75%+ global recycling rates and 35% lower energy use than aluminum cans, but corrosion remains a top headache. Here’s how to solve it.
1. Where Does Corrosion Strike?
| Corrosion Type | High-Risk Area | Real-World Scenario |
|---|---|---|
| Crevice Corrosion | Can body & lid seams | Cleaner cans rusting at seams |
| Galvanic Corrosion | Copper welds | Insecticide cans leaking at welds |
| Underfilm Corrosion | Damaged inner coating | Air freshener cans bulging inside |
| Pitting Corrosion | Bottom liquid pool | Water-based sprays developing pinholes |
2. Formula Protection (2025 Standards)
- Oil-based products (e.g., insecticides):Keep raw material moisture ≤50ppm (down from 100ppm) and add 5% ethanol to disperse water.
- Alcohol-based products (e.g., hairspray):Maintain pH ≥6.5 for domestic resins; add 0.15% sodium benzoate for 95% ethanol formulas.
- Water-based products (e.g., air fresheners):Use pH 7.0-9.0 for uncoated cans. Choose eco-friendly JC-300 rust inhibitor (1%-10% dilution protects for 1+ year).
3. Production Pitfalls to Avoid
- Stir non-homogeneous liquids at ≥60r/min during filling
- Use phase-separated filling for DME-water mixtures
- Conduct 180-day salt spray tests (double industry standard)
Q&A: Myths vs. Facts
Q: Thicker tinplate means better corrosion resistance?
A: No! A 0.2mm can with chromium-free passivation lasts twice as long as a 0.3mm regular can.
Q: Can chloride really “eat through” tinplate?
A: Yes! NaCl impurities in SLS caused full leakage in 1 month—switch to sodium lauroyl sarcosinate instead.
4. Choose the Right Supplier
Look for manufacturers with:
✅ Double-coated weld protection
✅ Water-based coatings (90% lower VOC emissions)
✅ 50-point airtightness tests per batch
Corrosion isn’t inevitable. With custom tinplate cans, smart formulas, and strict processes, your aerosols will stay intact for their 2-3 year shelf life.
