A desiccant is a dehumidifying agent which attracts moisture from the atmosphere. It adsorbs and holds particles of water to itself.
The three most common types of desiccants are clay, silica gel, and molecular sieve.
Indicating silica gel is a bead or granule that has been washed with a concentration of cobalt chloride (a heavy metal salt). The cobalt chloride is a deep blue color when dry and turns from blue to purple to pink as it becomes saturated with moisture.
Another use of indicating silica gel is with a moisture-sensitive product that will be inspected regularly, as the indicating silica gel gives a quick visual indication of how well the product is doing. Due to the presence of cobalt chloride, indicating silica gel desiccant should never be used in contact with products for consumption, such as food or pharmaceuticals.
Indicating silica gel is also available in special packet sizes for use in electronics, pharmaceutical, or food packaging.
In order to achieve optimal protection, desiccants should be used within a closed/sealed moisture barrier or a rigid/sealed container. Humidity Indicator Cards are generally placed inside the container to show the humidity level and to indicate when the desiccant needs to be replaced.
It depends. The amount of desiccant required is usually dependent on the following factors:
• Volume of air space to be desiccated
• Nature of the material to be protected
• Moisture surrounding the package
• Type of desiccant to be used
• Length of time for protection
• Atmospheric conditions (temperature and relative humidity) when/where the product is sealed and during subsequent shipment and storage
When Envirotronics receives a call from someone looking for desiccant, our Desiccant Specialists will ask a number of questions to determine responses to the above information so they can calculate which type and size of desiccant will work best for the particular application
You may use our Desiccant Calculator to determine the amount of desiccant for your application.
For further information on how to determine the amount of desiccant required for your application, please contact us