ZERUST® Z-PAK®

Yes, but we recommend placing and securing the desiccants away from the Z-PAK®. There should always be more Z-PAK® than desiccants in the same enclosure, as some types of desiccant may reduce the efficacy of the Z-PAK® depending on the location, type, and amount of desiccant used.

Z-PAK® has been tested with ZERUST® VCI bags to ensure that they are compatible during use. While it is possible to use Z-PAK® with non-ZERUST® VCI bags, we do not recommend doing so due to concerns about the compatibility between VCI chemistries. Always test before use if you intend to use Z-PAK® with other non-ZERUST® VCI products. We would also highly recommend using both Z-PAK® and ZERUST® VCI bags concurrently, as this will provide a more robust corrosion protection for the metal components you are protecting. Note that the Z-PAK® is a short-term (up to 3 or 6 months^‡, depending on application) fast-acting VCI, while the ZERUST® VCI bag provides a longer-term protection (for many months to years^‡). If your company decides to use non-VCI bags, such as plain LDPE bags, with Z-PAK®, be sure to check the dosage level and increase the number of Z-PAK® whenever necessary to ensure ample corrosion protection for your application.

Z-PAK® has been extensively tested to be compatible with our ZERUST® family of rust preventative oils and coatings. We, however, cannot claim the same for non-ZERUST® branded oils and coatings. Therefore, we highly recommend that you test before use with non-Zerust® products. Additionally, for the use of Z-PAK® with oils/coatings, precautions must be taken to ensure that the Z-PAK® is not soaked, stained, or covered with rust preventative oil, as this will prevent the VCI from diffusing out of the Z-PAK®.

Yes. Z-PAK® VCI does not interfere with the physical, chemical, or structural properties of the metal protected.

In general, we may prescribe using more Z-PAK® than usually needed in order to provide better ferrous (Carbon Steel, Silicon Steel, Stainless Steel, Cast Iron) metal protection – especially when there are concerns of process fluid contaminants or high risk of corrosion.

Under certain extremely humid conditions in the enclosure, the use of an excessive amount of Z-PAK® may lead to the formation of white crystals on the Z-PAK® packet and/or on surrounding areas near the Z-PAK®. The white crystals are from an excessive amount of the Z-PAK® VCI chemistry condensing and collecting with moisture. An excessive amount of Z-PAK® may also discolor yellow metals (such as Brass, Copper) present in the metal component. These white crystals are not corrosive and can be wiped away with alcohol/solvent. Trials should be conducted to find the optimum number of Z-PAK® to use for the condition of the enclosure and application.

It depends on the size of the package, the amount of Z-PAK® used, the temperature, and the humidity. Typically, after a few hours, the VCI is detectable in the package.

We may prescribe using more Z-PAK® than usually needed in order to provide better ferrous metal protection – especially when there are concerns of process fluid contaminants, high metal surface roughness, tightly packed components in the enclosure, high corrosion risk concerns, air leakage in an enclosure, challenging environment, etc.

There are many reasons that affect the duration of the protection, but a few common ones are: the amount of Z-PAK® used in a specific enclosure, the airtightness of the enclosure, temperature fluctuations during shipment/storage, relative humidity on the metal surface inside the enclosure, cleanliness of the metal surface, etc. International shipment applications typically undergo much harsher conditions (higher corrosion risk) than domestic shipment and storage. With multiple factors affecting the corrosion rate of metal surfaces, it is always recommended to conduct field trials to determine the optimum amount of Z-PAK® to use and set manufacturing control plans to reduce process variabilities.

For corrosion protection requirement beyond the indicated Z-PAK® protection period, use Z-PAK® with other ZERUST® products (such as ZERUST® VCI bags, ZERUST® Axxanol™ A35CD-32, and ZERUST® Axxanol™ 33CD) as part of the total corrosion protection system.

Not acceptable for use: Wet/damp material, sachets stuck together, material leaking out of the sachet, or broken seal. Acceptable for use: Due to anti-oxidants present in the outer packaging, slight discoloration of the sachet material might occur. Z-Pak® material might harden over time.

When Z-PAK® VCI Diffusers are stored incorrectly, such as in a very humid warehouse, excessive moisture may cause the Z-PAK® sachets to appear/feel hardened. However, this physical change will not affect the efficacy of the product and is still safe for use.

In order for the Z-PAK® VCI diffuser to work, the Z-PAK® must be allowed ample time to diffuse and saturate the inside of the enclosure with its VCI chemistry. This chemistry temporarily bonds to the surfaces of the metal inside the enclosure in order to protect them from corrosion. An enclosure that restricts or has no air movement/leakage will allow the Z-PAK® to reach the equilibrium saturation concentration inside the enclosure faster and start protecting the metal surface. If air leaks out of or into the enclosure, the Z-PAK® will have to diffuse and re-establish the equilibrium concentration inside the enclosure to start protecting again. Excessive air leakage will also deplete the Z-PAK® sooner (thereby shortening the protection period) as VCI escapes into the environment outside the enclosure. Therefore, keeping the enclosure airtight (no air leakage) is ideal, such as heat sealing the plastic bag opening or using hermetically sealed containers. When this is not possible, folding over and taping the plastic bag opening shut to create an airtight enclosure or adding tape to seal any openings or gaps in a rigid container will improve results significantly.

It will depend on the metal surface and the condition; in general, we advise the pack not to be placed in direct contact, if possible.

At constant high humidity in the enclosure for an extended period of time, the Z-PAK® VCI diffuser may become drenched with water condensation. This will affect the Z-PAK® effectiveness as water soaks the VCI chemistry out of the sachet and holds on to it – depleting the Z-PAK®, therefore, leaving less VCI chemistry for protecting the target metal surfaces. Therefore, never soak or immerse Z-PAK® in any type of liquid (oils, water, solvent, etc.).

Yes, but do not use more than the prescribed amount, do not put it in direct contact, and testing before use is recommended.

The VCI diffusing from the Z-PAK® has an “ammonia” smell. The amount of VCI diffused is within the acceptable US Occupational Safety and Health Administration (OSHA) limit. Please review the Z-PAK® SDS for details. As a precaution to users who are particularly sensitive to certain odors, newly received Z-PAK® VCI Diffuser (in the box of 1000) should be opened in well-ventilated areas of the factory/warehouse before transferring for use beside the assembly/work station. The initial accumulation of the Z-PAK® VCI inside the box may be overwhelming for some people, especially if stored in a warm warehouse or rack.

Yes, but always consult local and state regulations before disposal as policies may differ between cities or change over time.

For optimal corrosion protection, it is recommended to use Z-PAK® Packets within 2 years of the shipment date, as their effectiveness may diminish over time, especially if the packets have been exposed to air, moisture, or sunlight. Using packets beyond the 2-year shelf life is not advised unless they have been stored in optimal conditions (cool, dry, sealed packaging) and tested for vapor inhibiting ability.

Email sds@ntic.com to request the Safety Data Sheet for Z-PAK® Packets and/or all other ZERUST® products.