Handling and Usage Guide for Ultra-Vanshield Gasket Products
Congratulations on your selection of the premier EMI/RFI Shielding product for your application. Though the Ultra-Vanshield product is a durable and easy to use item, as with any conductive gasket there are some simple steps that should be taken to maintain the electrical integrity of the product.
Storage:
- All Ultra-Vanshield products are shipped in their own environmentally sealed bags to protect the product from chemicals or dirt that may be present in your storage location. When not in use, the product should be kept in these sealed bags.
- Products containing pressure sensitive adhesive (PSA) should be kept stored at a maximum temperature of 95° F and a maximum relative humidity of 70%. The product may experience a short-term (less than 4-5 weeks) exposure to a maximum temperature of 140° F and a maximum relative humidity of 80% without damage.
- Shelf life of material under the above conditions is typically one year for items with PSA and ten years for products without PSA.
Usage and Installation Guidelines:
- As with any EMI product, it is important to eliminate the chance of deposition of an insulative barrier between the product and the two conductive surfaces to which it is being applied. First, the metals should be free from of oils and/or non-conductive materials. Second, the gasket should be clean. This can be accomplished with the following precautions.
- In order to avoid deposition of insulating oils on the product surface, cotton gloves preferably, or rubber gloves should be used on the factory floor to handle the gasket. If this is not possible, care should be taken that workers hands are clean and free of grease, hand lotions, food oils, etc., prior to handling the gasket.
- Regular cleansing of the gasket once in application is generally not necessary. However, if the gasket does got soiled either prior to application or in duty, the gasket should be cleaned with hot water and a mild soap (Palmolive) and thoroughly rinsed with water. Do not rub, or scrub the gasket with an abrasive pad.
- Hydrocarbon solvents such as toluene or mineral spirits
- Chlorinated solvents such as trichloroethylene
- Ketones such as acetone
- Alcohols
In cases where the product will be significantly exposed to the above materials, special Ultra-Vanshield materials are available.
If soap and water does not provide significant cleaning, rubbing alcohol (dilute isopropyl alcohol) can be used as a light solvent to clean the gasket. However, numerous cleanings with this material or aggressive rubbing is not recommended as the alcohol will tend to slightly and temporarily swell the gasket
- Stretching or elongation of the gasket may occur during installation. Excessive stretching (over 50% local elongation) can cause reduced shielding quality and should be avoided.
Gaskets with Pressure Sensitive Adhesive (PSA) require some extra steps in application;
- Mounting surfaces should be clean and free of grease, oils or liquids.
- Upon installation, the release liner should be carefully separated from the adhesive using a fingernail or sharp edge. Touching the adhesive with fingers should be avoided after removing the release liner as dirt and hand oils will reduce adhesion.
- The gasket, typically positioned and pressed into place, should be installed with a minimum of stretch, generally less than 5%. Being an elastomeric material, stretched gasket will attempt to return to its original shape. This may result in the gasket loosening or pulling off the intended substrate. The Gasket may be moved for up to 90 seconds after being applied, but this should be avoided if possible. Subsequent movement could reduce adhesive strength and may elongate the material; possibly affecting it's electrical properties. Ideally, PSA will reach its ultimate bond strength after 24 hours at room temperature.
Other factors to consider: pressure sensitive adhesives PSA for extusions.