The 28mm aluminum ROPP bottle cap is a widely used tamper-evident solution for glass bottled water. This cap is specifically designed to provide visible evidence of tampering, ensuring the product remains untouched before first use. It is widely applied in packaging for mineral water, purified water, soda water, juices, soft drinks, alcoholic beverages, edible oils, and some health supplements and pharmaceutical liquids.
Tamper-Evident Technology
The 28mm ROPP aluminum water cap achieves tamper-evidence through a mechanical interlock (tamper ring) and destructive opening mechanism. The tamper-evident ring is engineered with a break force of 8N, ensuring it is easy enough for female consumers to open while maintaining security integrity.
These 28mm tamper-evident aluminum ROPP caps are often lined with PE (polyethylene), butyl rubber, or silicone rubber materials to ensure optimal sealing performance and compatibility with various liquids.
What Does “28mm” Mean?
“28mm” refers to the outer diameter of the bottle neck, a standard size for water, juice, and pharmaceutical bottles.
ROPP Cap Specifications
Diameter – International Standard Sizes: | 18×12mm ROPP Cap 20×12mm ROPP Cap 22×15mm ROPP Cap 25×17mm ROPP Cap 28×18mm ROPP Cap 30×24mm ROPP Cap 31.5×18mm ROPP Cap 31.5×24mm ROPP Cap 33.5×24mm ROPP Cap |
| Material | Aluminum |
| Colors | Silver / Gold / Black / Red / Custom |
| Customer Service Options | Embossed logo, silk screen printing |
| Certifications | ISO9001, CE |
| Usage | For glass bottles |
| Origin | Made in China |
| MOQ | 10,000 pieces |
| Lead Time | Trial order: 3–10 days Bulk order: 25–45 days |
Core Advantages of 28mm ROPP Aluminum Water Caps
Security: Offers reliable tamper-evident protection to prevent contamination or adulteration.
Consumer Confidence: Clear tamper-evidence reassures consumers of the product’s originality and safety.
Versatility: Suitable for various liquid types and filling processes.
Customization: Color and logo printing available for brand enhancement.
Eco-Friendly: Made from recyclable aluminum, aligned with sustainable packaging trends.
Application Fields
Premium bottled mineral or natural water: e.g., glass-bottled Italian or Swiss glacier water
Functional or health beverages: where product purity and safety are critical
Oral liquids / Pharmaceuticals: such as syrups, nutritional solutions requiring pharma-grade sealing
Condiments / Edible oils: where oxidation and leakage must be prevented
Perfume, essential oils, and other small-volume glass bottles
Comparison with Plastic Bottle Caps
| Feature | 28mm Aluminum cap | Plastic Water Cap |
| Product Image | Premium, elegant, and refined | Good (tamper ring present but less visible) |
| Tamper-Evidence | Excellent (visible break ring via ROPP design) | Good (tamper ring present but less visible) |
| Sealing Performance | Excellent, pressure-resistant, suitable for various filling methods | Good, easy to reseal |
| Cost | Higher | Lower |
| Manufacturing Process | Complex, requires specialized equipment | Simpler, high production efficiency |
| User Experience | Slightly more force required, break ring visible | Easy to open and reseal |
| Environmental Impact | Highly recyclable, eco-friendly | Recycling/degradation challenges (some improved plastics exist) |
| Application | High-end bottled water, spirits, pharma, carbonated beverages | Mass-market water, food, daily chemical products |
About HAOMEI Aluminum
HAOMEI Aluminum is a trusted supplier in the packaging industry, specializing in screw-type aluminum caps, plastic anti-counterfeit bottle caps, and high-end aluminum-plastic composite caps. The company boasts advanced technology, modern production facilities, and a comprehensive quality inspection system. HAOMEI is ISO certified.
Our products are exported to more than 40 countries and regions, including Europe, the United States, South America, South Africa, Southeast Asia, Russia, Central Asia, and the Middle East.
