ADSORBENT BREATHER Disk Drive The Adsorbent Breather Filter (ABF) is comprised of a filtration membrane, adsorbent element, and a pressure-sensitive adhesive ring for securing the filter to the A diffusion channel can be incorporated within the adhesive layers. The ABF is designed to provide protection from particles, hydrocarbons, and acid gases. The high efficiency filtration membrane removes particles from incoming air and encapsulates the adsorbent element. The adsorbent is specially formulated to control humidity and to adsorb acid gases and hydrocarbons from internal and external sources. The most common adsorbents and their associated functions are as follows: • Activated Carbon: Relative humidity control and adsorption of hydrocarbons • Chemically Treated Activated Carbon: Relative humidity control and adsorption of acid gases and hydrocarbons • Silica Gel: Relative humidity control The ABF is located on the inside of the drive, preferably with a diffusion channel between the breather and the outside environment. The filter location should be in low pressure area of the disk drive so that air can enter through the breather. Generally, the best location is on the cover as close as possible Airflow restriction into the drive is affected by the size of the filter, choice of filter materials, and the design of the diffusion channel. There is a trade-off between the airflow restriction and the amount of diffusion protection. Adsorbent Material PTFE Membrane

ADSORBENT BREATHER FILTER (ABF) PRODUCT GUIDELINES AND SPECIFICATIONS Contamination Control Silicone-free release liner option available. Adhered with a high-temperature, low-outgassing, pressure-sensitive adhesive. Designed to pass the most stringent cleanliness specifications. Manufactured in a cleanroom environment DONALDSON CHEMICAL BREAKTHROUGH TEST Time (mins) An example of a typical chemical breakthrough graph of an ABF. Actual results vary depending on overall filter size, adsorbent type, and quantity. ABFs are designed to meet customer specifications. Contact Donaldson today for more...