When metal parts are exposed to moisture, oxygen, or temperature swings during storage or shipping, rust and corrosion become a real threat. That’s where VCI bags come in.
VCI stands for Vapor Corrosion Inhibitor — a specialized type of poly bag designed to protect metal components from rust without oils, coatings, or desiccants. At M Plastics, we manufacture custom LDPE VCI bags for customers in automotive, aerospace, electronics, and other metal-sensitive industries.
What Is a VCI Bag?
A VCI bag is a polyethylene bag made with corrosion-inhibiting additives blended directly into the resin. These additives release an invisible vapor that forms a molecular shield on the surface of metal items stored inside the bag.
The result: clean, dry protection against corrosion for ferrous and non-ferrous metals — often without extra materials like paper wraps or anti-rust oils.
How VCI Technology Works
The VCI additive is incorporated into the LDPE during extrusion. When a metal item is sealed inside the bag, the additive slowly vaporizes, creating a corrosion-inhibiting atmosphere. That vapor:
- Bonds to the metal surface
- Blocks moisture, salt, and oxygen from reacting with the metal
- Dissipates once the part is removed, leaving it clean and ready for use
When and Where to Use VCI Bags
VCI bags are ideal for protecting metals during:
- Export shipments, especially overseas ocean freight
- Long-term storage of inventory
- Electronics and tool packaging
- Metal components and machine parts
VCI Formats We Produce
- Layflat bags for small parts or kits
- Side-gusseted bags for larger or bulkier items
- Wicketed VCI bags for high-speed automated packing
- Custom sizes, mil thicknesses, and print options
Contact our sales team for specifications on the VCI film we run for your application.
Final Thoughts
Rust can ruin quality, slow down assembly, and cost companies thousands in lost parts. VCI bags offer a clean, dry way to protect metal goods throughout the supply chain — without adding steps to your process.
Packaging metal parts? Request a quote and tell us what you’re protecting — we’ll help you spec the right VCI bag.
Have a Packaging Question?
M Plastics manufactures LDPE bags and film in Los Angeles with in-house extrusion and printing. Tell us what you're packaging and we'll help you spec the right bag.
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