The use of volatile chemicals to inhibit corrosion dates back to the 1930's and beyond. VCI's are just beginning to be used in the electronics industry, and in particular for the excellent protection of copper, aluminum and most solders as well as other metals.

The principal of VCI chemistry is the passivating* of a metal part by surrounding the part with a vapor of a chemical that will actively attach itself to the metal as long as it is kept in the enclosure. The thin layer of chemical (possibly one molecule thick) protects the metal from oxygen reactions, thereby effectively reducing corrosion for many years. Removal from the enclosure and exposing the metal to the atmosphere will cause the volatile chemical to dissipate from the metal surface and bring the metal back to its original condition with no left over contamination that needs to be removed.

VCI chemicals have the common property of Sublimation , meaning the ability to go from a solid to a gas without going through a liquid phase. An increase in temperature will cause most chemicals to become a gas. By placing the chemical in an enclosure, the entrapped vapor will soon saturate the air causing the reaction to come to equilibrium and slow down or stop any further gas production. Cooler temperatures slow down both the corrosion reaction and the sublimation reaction.

The ability of the VCI materials to work in conjunction with our static control additives further enhances the successful use of VCI s in the broad electronics markets of today. By using a single material with these dual properties, we offer an ideal solution to industries requiring protection from corrosion as well as static. Due to the miniaturization that has occurred in the electronics industries, contamination has become a large, yet solvable, problem. A super clean package is absolutely required. Recent testing has proven that VCI chemistry is a safe and effective method of providing packaging materials for this market.

The attraction between two smooth surfaces (Van der Walls forces) can cause sticking of a metal part to the surface of a flat plastic bag. During periods of high humidity a thin layer of moisture can develop inside of an enclosure (Green House effect) and a pool of water will develop and may cause the blocking of the VCI from reaching the metal surface. Corrosion develops in these areas.

MBR

Our new Multiple Ribbed Bags developed by Gemini Plastic Enterprises Inc., has a ribbed formation on the inside of the bags eliminating the above two problems. An added benefit can be obtained in that the ribbed construction is able to offer additional surface area of the product within the bag to be exposed, and in effect allowing additional VCI s to be released. The saturation within the enclosure will occur quicker and be more effective.

ANTISTATIC

Gemini Plastics antistatic films either meet or exceed the surface resistivity and static decay rates as specified in Mil-B-81705 Type 2. We have been certified to Mil-B-81705-B Type 2 by the Department of the Navy since 1980. For ultra clean film and bags we use additive free virgin low density polyethylene and our amine free antistatic agent with color as an option.

 * passivate....To treat or coat (a metal) in order to reduce the chemical reactivity of its surface.