Cor-Pak EX VpCI Film – 12″ x 12″ 1.25 mil (Cortec® Cor-Pak® EX)

Description

Cor-Pak® EX VpCI® film is a 1.25 mil (32 µm) high-density polyethylene sheet extruded with Cortec’s vapor-phase corrosion inhibitor, supplied here as 12″ × 12″ sheets perforated on a roll, 1,000 sheets per roll, the size for interleaving small stampings, blanks, bearings and machined parts in trays and cartons. It does the job of VCI paper, laid between parts or wrapped around a component, in a film that does not tear, shed fibers, absorb oil or go limp in humid air, and it adds a moisture barrier that paper cannot. Parts come out ready to use with nothing to degrease.

Cor-Pak EX protects ferrous and most non-ferrous metals and is rated 2, inside storage, in the Cortec Product Consultation Guide on carbon steel, stainless steel, cast iron, aluminum alloys, galvanized steel, copper, brass and solder: enclosed packaging, uncovered indoor storage, and shipment inside a crate or container. At 1.25 mil it is not a stand-alone outer package for heavy parts; it is the interleaf and inner wrap that keeps surfaces from touching and puts an inhibitor source against the metal, with a VpCI-126 bag or liner around the load as the outer barrier. HDPE gives it a better moisture barrier than the same gauge of LDPE, so Cortec positions it for hot, humid climates and for parts nesting in trays. It replaces VCI kraft paper interleaving, wax paper and oiled slip sheets, and it is recyclable.

Typical applications

• Interleaving between stamped blanks, plates and sheet-metal parts
• Layering parts that nest in trays, dunnage and returnable containers
• Wrapping individual machined components, gears and bearings
• Slip sheets between layers of castings on a pallet
• Inner wrap inside a VpCI-126 liner for export shipments
• Shrouding assemblies and sub-assemblies between operations
• Replacement for VCI paper where fibers, dust or paper tearing are a problem
• Hot and humid climates where a moisture barrier is needed against the metal

How to use Cor-Pak EX

1. Prepare the parts. Parts must be clean, dry and at room temperature, with no standing water, cutting fluid or fingerprints on the metal. Do not wrap parts still wet from a washer.
2. Interleave or wrap. Tear sheets from the roll at the perforation. Lay one sheet between each layer of parts, or between each part and the tray, so no bare metal touches bare metal. For a single component, wrap the sheet fully around it with the ends folded under: one layer against the metal, minimal trapped air. 12″ × 12″ sheets can be overlapped for a larger part or cut down for a small one.
3. Close the outer package. Put the tray, carton or pallet inside a VpCI-126 bag or gusseted liner, or under a VpCI-126 sheet, and close it; the outer film holds the vapor concentration.
4. Let the vapor work. Once closed, the VpCI vaporizes and condenses as a molecular layer on every metal surface in the enclosure, including surfaces the film does not touch. For a large crate or long storage add a VpCI-130-series foam pad or BioPad.
5. Unpack and dispose. Remove the sheets and use the parts; nothing to degrease. The film is recyclable HDPE.
6. Store the packaging. Original sealed packaging, indoors at ambient temperature; shelf life up to 24 months.

Combining with other VpCI packaging

The standard system is Cor-Pak EX between and around the parts, a VpCI-126 gusseted liner or VpCI-126 bag as the outer enclosure, and a VpCI-132 foam pad or BioPad in the void for long storage. Where the parts are oily and the package needs to absorb rather than repel, use VpCI-146 paper for the interleaf instead. Cushion heavy or sharp parts with Cor-Pak VpCI bubbles. Parts should be clean and dry before they are wrapped; see Build-All and Magido aqueous parts washers, and follow the wash with VpCI-377 or BioCorr if the parts need a dry-film rust preventative under the packaging.

Where it fits in the Cortec line

Cor-Pak EX is the thin HDPE interleaving film in Cortec’s range. VpCI-126 Blue is the heavier LDPE film for bags, liners and tubing that form the outer enclosure; VpCI-146 and VpCI-144 are the kraft-paper interleaves, 146 plain and 144 with a moisture-barrier coating; Cor-Pak VpCI Liner Film is the 1 mil HDPE sibling used for foam-in-place packaging; EcoWeave is the woven sheet for heavy or sharp loads; Cor-Pak VpCI stretch film unitizes the pallet. Within Cor-Pak EX the choice is sheet size, 12″ × 12″ or 18″ × 18″, with 36″ × 33″ sheets and 36″ and 48″ × 500′ rolls available on request. The VpCI product selection guide covers the whole packaging line.

Field notes

A Detroit automaker’s steering gear and axle parts rusted on the way to Mexico despite oil plus a competitor’s VCI paper. Lining the steel shipping bins with VpCI-126 film and interleaving the layers with Cor-Pak VpCI film kept them rust-free from damp Michigan through hot, humid transit, with reusable packaging. (Cortec Case History #097)

A Michigan brake-rotor maker replaced liquid rust preventive with VpCI-146 interleaving about 15 years ago. When it automated packing in 2020, the robot line cuts 48-inch by 10,000-foot rolls of VpCI-146, layers paper and rotors on plywood and auto-wraps the pallet in Cor-Pak VpCI stretch film, which replaced a competitor’s bags. Ten-plus years on paper, residue-free. (Cortec Case History #716)

A North Carolina precision-rod maker lost its imported specialty VCI paper during the COVID shipping disruption. Machine-grade 1.5 mil Cor-Pak VpCI stretch film, stronger and stretchier than VCI crepe paper, was converted to small rolls for the wrapping machine and met every requirement from domestic stock. (Cortec Case History #773)

Specifications

Product	Cor-Pak EX VpCI film, high-density polyethylene extruded with vapor-phase corrosion inhibitors
Gauge	1.25 mil (32 µm); Cortec lists 1.0–1.25 mil (25–35 µm)
Metals	Carbon steel, galvanized steel, stainless steel, copper and alloys, aluminum and alloys, brass, zinc
Consultation guide rating	2 – inside storage, on carbon steel, stainless steel, cast iron, aluminum, galvanized steel, copper, brass and solder
Construction	High-density polyethylene extruded with vapor phase corrosion inhibitors
Barrier	Excellent moisture barrier for its gauge; positioned for hot, humid climates
Moisture transmission	0.5 g per 100 in² per 24 h (Cortec comparison table) — comparable to 45 lb PE-coated kraft
Use	Interleaving, layering parts nesting in trays, wrapping components, inner wrap inside a VpCI-126 enclosure
Formats	Rolls and sheets, standard and custom sizes; perforated sheets 12″ × 12″, 18″ × 18″ and 36″ × 33″; rolls 36″ and 48″ × 500′
Sheets per roll	1,000 sheets per roll
Recycling	Recyclable HDPE
Note	Gel ink transfer is possible when the film is used over petroleum-based coatings
Shelf life	Up to 24 months stored indoors at ambient temperature in original sealed packaging
Size	12″ x 12″ 1.25 mil
Shipping weight	8 lb (3.6 kg)
Availability	In stock
Cortec product number	20802594

Solvent Recycling Systems is an authorized Cortec® distributor. See the full Cortec VpCI line, browse the VpCI product selection guide, or contact us for volume pricing and lead times.