SHIP - STORE - PROTECT

Corrosion Intercept Films

Intercept Shrink Film Provides 3-Way Protection:
Anti-Corrosion, Anti-Static, Anti-Mould/Mildew

Intercept Technology is a revolutionary product developed by Bell Labs. This new technology employs a reactive polymer that reacts with and neutralizes the gases that cause metals to corrode or rust. Intercept Technology currently is in use by Fortune 500 aerospace and telecommunication companies to provide stable, effective, long lasting corrosion and Electro-static discharge (ESD) protection while neutralizing destructive mold and mildew coming into contact with the resin.

Metallic corrosion is caused primarily by the reaction of corrosive or reactive atmospheric gases. These reactive gases (ozone, hydrogen sulfide, carbonyl sulfide, hydrogen chloride, sulfur dioxide) easily combine with metal surfaces causing corrosion and oxidation. Bell Labs determined that up to 80% of their latent, or premature field defects were being caused by, or related to corrosion.

Gases containing sulfur and chlorine are the major gases causing corrosion. Preventing corrosion means keeping these and other reactive gases from attacking or contacting the metal surfaces. Keeping these gases away from the metal surfaces will keep the surfaces clean and free of oxidation and corrosion.

How do you effectively keep the gases away? The answer is Intercept Technology * utilizing a revolutionary approach of inserting highly reactive Copper into the polymer matrix. This backbone of Copper forms a reactive barrier to the gases. Because of this torturous path through the Copper it is impossible for these gases to pass through Intercept to attack what is inside the shrink-wrapped film. While inside the container, the Intercept acts as a preferential corrosion site reacting and cleansing trapped air, making a safe micro-environment for your stored/shipped objects. Intercept also provides protection from static electricity – the silent killer of electronics.

Advantages

Intercept has been used successfully for years protecting everything from satellites and sensitive guidance systems, optical switches, major works of art, sculptures, silver, rubber components, paper, and even guitar strings. The copper in the material helps control the formation and growth of moulds and mildew when in intimate contact with the surface. One hallmark of this new polymer class is that it is so versatile. Bell Labs developed the Intercept technology as a way to better protect their own systems. They discovered that corrosion weakens electrical components, making them more sensitive to ESD effects. Also, corrosion adversely effects solderability – it is very difficult to solder through corrosion or oxidation. Intercept keeps surfaces pristine, enhancing solderability and extending useful operating life of the electronic system or component.

The technology now is available by FPM as Intercept Shrink film. Ideal for military and commercial aviation, boat, equipment, and materiel shipment/storage, Intercept provides 3-way protection, using only 1 product.

Intercept provides 3-way protection, using only 1 product

Frequently Asked Questions About Corrosion

  1. What is corrosion? Corrosion is an electrochemical reaction between metals and their environment to form metal oxides or salts.
  2. What causes corrosion? The presence of corrosive chemicals or gases such as chlorine, sulfur, oxygen, nitrous groups and their compounds. These chemicals cause an electrochemical reaction on the surface that results in corrosion.
  3. What is atmospheric corrosion? Corrosive gases in the atmosphere caused by the burning of fossil fuels, from saltwater evaporation, electrical discharges such as lightning, industrial processes, and engine exhaust release chemicals that contact metal surfaces and react to form corrosion.
  4. What is Corrosion Intercept? Corrosion Intercept is a reactive polymer developed by Bell Laboratories to prevent corrosion. Corrosion Intercept acts as a barrier to corrosive gases by neutralizing them as they penetrate the polymer compound. Corrosion Intercept acts as a scavenger of any latent corrosive gases present and neutralizes them as well. No chemicals or deposits are left on the protected metals.
  5. What is Corrosion Intercept Stretch Film? Corrosion Intercept stretch film is a film that contains a discrete layer of the Corrosion Intercept polymer. The layer is 100% Corrosion Intercept. The film also has the properties of a stretch wrap film with high elongation and a layer of high tack, which binds the package together. These properties make it suitable as a corrosion resistant packaging film. By using a thin film and wrapping an item a number of times the stretch wrap acts as a water vapor barrier, a strong container, and in this case a barrier to atmospheric corrosion. Corrosion Intercept Stretch Film contains no migrating plasticizers or chemicals that might discolor metals or affect electronic components.
  6. What is VCI? VCI is an abbreviation for Volatile Corrosion Inhibitor. They may contain any of a variety of often hazardous chemicals, often including a family of amine products, which when combined with aliphatic hydrocarbons or nitrates migrate from the packaging and deposit themselves on the surfaces to be protected. The temperature and the vapor pressure of the particular VCI being used control the rate of deposition. If the temperatures are high the VCI is used up quickly, if low the VCI may not be activated. Published MSDS sheets may, or may not, indicate potential health and safety implications from the vapors emitted by these products.
  7. How long will the product be protected? Corrosion Intercept will last for years depending upon the concentration of corrosive chemicals in the atmosphere. Properly stored film has an indefinite shelf life. There are no products that will migrate from the film to cause depletion and loss of effectiveness.
  8. Will the Corrosion Intercept work if there are oily deposits on the surfaces of the metals? Corrosion Intercept may be used in conjunction with light machine oils or non-VCI containing oils. Fingerprints need to be removed and the metal to be protected needs to be dry.
  9. How do you know if the product needs to be repackaged? Corrosion Intercept will change color as it is used up. If the product turns charcoal gray or yellow it is time to rewrap the product.
  10. Can Corrosion Intercept be recycled? There are no harmful chemicals in Corrosion Intercept. It may be recycled.
  11. Will Corrosion Intercept protect a product inside corrugated packaging? No. Film wrapped around the outside of a corrugated carton cannot protect the metal inside the carton. Corrosion Intercept will ensure that no additional pollutants enter the system and no reactive gases will be able to penetrate the packaging. Under normal conditions the major source of corrosive gases will come from external sources, not from the carton.
  12. Do varying temperatures affect the performance of Corrosion Intercept? No. However, condensation on the metal may result in corrosion that cannot be prevented. In these situations a non-metallic desiccant is recommended. In addition to being clean and dry, the items to be packaged should be near or at ambient temperatures to minimize condensation.
  13. How long will Corrosion Intercept protect metal products stored outdoors? Protection is dependent upon the external storage conditions. Wide changes in day and night time temperatures, proximity to heavy industrial sites, waste sites, or ocean locations. Long term exposure to sunlight and how well the product is wrapped are other variables that need to be considered. Please contact us for specific information regarding packaging and storage recommendations.
  14. How many Corrosion Intercept products are there? Do I need a different one for each metal to be protected?The reactive polymer protects both ferrous and non-ferrous metals. Unlike VCI's the Corrosion Intercept product is not dependent on vapor pressure, temperature, or type of cyclic amine used. You don't have to stock different formulas for each metal or temperature condition.
  15. Do residual chemicals on the metal interfere with the Corrosion Intercept's effectiveness? Corrosion Intercept acts as a barrier to atmospheric corrosion and acts as a preferential corrosion site for corrosive gases inside the wrapped product container. Corrosion Intercept cannot reverse any corrosion that has already occurred or stop corrosion if the corrosive element is in intimate contact with the surface to be protected. All surfaces should be clean and dry prior to packaging.
  16. Will Corrosion Intercept affect plastics or cause discoloration of metals? Corrosion Intercept has a neutral pH and will not affect optical plastics or glass. Corrosion Intercept contains no volatile compounds that could discolor metals.
  17. How does Corrosion Intercept compare to corrosion inhibitor papers? Corrosion Intercept is a polyethylene film with excellent moisture vapor barrier properties. Papers, on the other hand, are more absorbent and more porous than plastic films.
  18. Are gloves required to handle metal surfaces? Yes. The oils present on the hands will initiate corrosion of the metal. All surfaces of the metal parts should be clean and dry.
  19. How does Corrosion Intercept compare to the cost of using Cosmoline or oils for the protection of metals? Many oils and coatings contain hazardous substances and require protective clothing during application. In addition the labor cost involved in application and removal is significant compared to the one time wrapping of the product. The time from receipt to immediate use of a product wrapped with Corrosion Intercept is minutes compared to hours for coating removal. Solvents used for cleaning metal surfaces may be hazardous and require costly disposal and additional record keeping.
  20. Does protective clothing need to be worn to handle Corrosion Intercept? No, Corrosion Intercept is non-hazardous and non-allergenic.
  21. Does Corrosion Intercept attract dust? Because Corrosion Intercept does not leave any residue or coat the product to be protected there is nothing to attract dust to the surface of the metal. A recent paper published by Boeing Corporation indicated that dust could cause intermittent electrical failures. Dust may be attracted to surfaces with oil deposits or other organic coatings.

Corrosion Inhibition

Corrosion on circuitry can be confined to mainly three main factors - atmospheric corrosion of the metals, galvanic corrosion, and fungus attack. We will handle each in turn.
Atmospheric corrosion is one of the most prevalent and most easily recognized and understood forms of corrosion. Atmospheric corrosion occurs whenever atmospheric gases attack a metal surface. Metals corrode (tarnish) by reaction with common gases in the atmosphere. These corrosive gases react with both Ferrous (Iron based) and Non-Ferrous metals, however these gases are the primary cause for Non-Ferrous metal (such as Silver, Tin, Copper, Brass, etc.) corrosion, though they are still extremely significant in Ferrous corrosion as well.

The common corrosive gases and examples of how they are produced:

Metals in nature always assume their most stable state, which in most cases are sulfides, chlorides, oxides or other salts. However, for metals to be used in electronics, as well as for cosmetic applications, these metals are refined and purified. Once the metal has been purified it can conduct electricity. However, purified metals are unstable and seek to react with corrosive gases - which are also chemically unstable. According to Rebecca Starling of General Dynamics:"90% of the trouble with corrosion in missiles originates on the drawing board. To be certain of adequate protection from corrosion, the designer must anticipate conditions during inert life (transportation, storage, rework, and repair) as well as during active operation. The designer’s responsibility is (1) ascertain the environmental extremes likely to be encountered - and (2) to provide corrosion protection against these conditions."

We need to recognize the fact that metals begin corroding as soon as they are exposed to the environment. We need to prevent the contact the metal has with the environment. We also recognize the fact that the most sensitive time for a metal is when it is inert. This is because once electricity is flowing through a metal, once the metal or circuit is active, the likelihood of corrosion drops significantly. It drops significantly because the metal is now temporarily being chemically altered by flowing electricity. This change makes the reaction with a corrosive gas more difficult (less driving
force) and hence far less prevalent or likely. In storage, shipment or manufacture, the circuit and the metals are not active and are targets for corrosive gas attack.

Corrosive gases are extremely active, more active as the temperature increases. Everything in nature seeks to be chemically (electrically) stable. Gases seek the path of least resistance, or in other words, seek the path with the highest driving force. Since metal surfaces are an ideal site, the surfaces must be protected. Intercept provides protection by being a preferential corrosion site. The gases find reacting with Static or Corrosion Intercept to be easier (higher driving force), so they naturally go to the Intercept. Intercept is preferential because of a combination of high level of surface area of its reactive components an also because of the chemical changes done to these Intercept active sites. By enclosing a metal object in Intercept, the Intercept creates a micro-environment cleansing the air of these reactive gases. By minimizing the exchange of air in the package, the Intercept continues to provide this clean micro-environment on the inside. Meanwhile, the Intercept protective enclosure prevents new corrosive gases from penetrating through the Intercept - at 7 ppb it takes Sulfur 10 years to penetrate .001" of Intercept.

This testing is the same whatever the substrate that the Intercept is coated onto. The corrosion protection is directly tied to how much Intercept is available - how thick the coatings are. The thicker the coating, the longer the protection, on any substrate.
One misconception of corrosion is that it is caused by water. Water does act as an excellent carrier for these corrosive gases and reactive ions. Ions are easily dissolved in water and are then carried by humidity, water vapor and steam. Water also acts as an accelerator - increasing the reaction rate of these gases and ions with the metal surfaces. However, water of and by itself does not cause corrosion - its what is in the water that does the damage. Intercept helps counteract these ions and water borne contaminates - for water permeating an Intercept film.

One of the other major types of corrosion, especially for Ferrous metals, is galvanic corrosion. Galvanic corrosion is caused by the junction of two dissimilar metals. "Galvanic corrosion is caused by a flow of electricity from one metal to another or to a recipient (i.e. soil) of some kind, or from one part of the surface of the metal to another part. Differences in the metal can be seen as composition of the metal itself varying, or differences in grain boundaries, or localized shear or torque from the manufacturing process. Almost any lack of homogeneity of the metal surface or its environment may initiate a galvanic corrosion attack, by causing a difference in potential. Contact between dissimilar metals also causes this galvanic current to flow, due to the difference in potential of the two, or more, different metals." . The relative passivity of stainless steels or other metals or alloys is due to a presence of a corrosion-resistant oxide film on their surfaces. In most natural environments, such metals remain passive to corrosion but can still cause galvanic corrosion. This passive state for stainless steel can be changed to an active state (can corrode) when Chloride concentrations are high, such as in or near seawater (ocean travel or manufacturing within 25 miles of an ocean surface). So, galvanic and atmospheric corrosion can easily co-exist in severe environments, even with materials that are corrosion resistant.

Intercept is one of the few materials that is effective against galvanic corrosion. Circuit boards normally have several different metals - such as Copper, Tin, Silver, etc. These metals are at different levels in the galvanic series, so they will react with each other. Intercept, being a semi-conductor material has an activation threshold less than the galvanic current for these metals. When Static Intercept is in intimate contact with these metals the galvanic current is shunted to the Static Intercept - Intercept breaks the electron path between the dissimilar metals. Intercept acts as a sacrificial anode, protecting the galvanic couple and lengthening the life of the circuit board because it is protected during process, shipment and storage.
Microbial attack came to widespread notice during World War 2 when so much damage was done by fungus in the South Pacific. Although they thrive best in warm, humid environments, fungi can exist under cold or dry conditions. As more non-metallic materials are used in electrical and electronic assemblies, increased attention must be devoted to protection from fungal attack. In one large missile system, over 200 items were found to support fungus growth. However, the prevention of fungal attacks on circuit boards and their substrates is difficult. Even the use of materials that do not support fungal growth may not solve the problem because fungi can exist on a given material without feeding on it, creating an undesirable film deposit on the material.

Intercept can also protect against this fungal attack. It is a well documented fact that Copper in the proper form can retard fungal and microbial growth. Intercept, with its core of activated Copper, acts as a passive fungicide. Intercept will not actively kill the fungi, however Intercept will interfere with its growth and reproduction, ultimately killing the fungi. The micro-environment created by Static Intercept will be fungi free within a relatively short period of time increasing protection for past being transported to or from Asia, and other hot, humid locations.

Intercept provides the three layers of protection.

  1. protection from atmospheric corrosion
  2. protection from galvanic corrosion
  3. protection from fungi attack

Companies using Static Intercept have reported substantial decreases in latent defects (caused almost exclusively by corrosion and ESD) as well as in work in process failures (WIP materials) leading to increased yields. Intercept is safe and effective for direct wafer contact, as well as for storing and shipping boards, assemblies, missile components, and irreplaceable art works.

By preventing corrosion on the circuits the useful life of the circuits will be extended. By eliminating corrosion soldering problems can be completely eliminated - this is a major benefit for board, circuit and component manufacturers. Finally, latent defects are a major concern for all levels of electronic assemblies. Bell Labs determined that corrosion plays an extremely significant role in causing latent or field defects.

Corrosion cripples a circuit by reducing the conductive paths that the electricity has to flow over. As metals corrode they go from being conductive to insulative. This is a chemical change that steals productive life from the electronics. The thinning of the conductive paths, due to spots and fingers of corrosion, also reduces the heat dissipating properties of the metal. Corroded metals cannot dissipate heat like a conductive or pure metal can. This reduction of the heat dissipation leads to a build up of heat on the conductive paths and eventually a burn through, rendering the conductive path, and the circuit worthless. By using Intercept the conductive paths are protected during the time when the circuit and electronics are most susceptible to damage - namely manufacturing, shipping and storage. The secret is protecting the part during these critical times.