What is Hygroscopic
Hygroscopic refers to the property of a material or substance to readily absorb and retain moisture from the surrounding air. It describes the ability of certain chemicals or substances to attract and hold water molecules when exposed to humid environments. This characteristic is particularly relevant in the PCB industry, where hygroscopic materials are commonly used as desiccants or moisture absorbents to prevent water damage to electronic components.
One example of a hygroscopic material used in the PCB industry is silica gel, which is often employed as a desiccant in PCB packaging. Silica gel has a strong affinity for water and can effectively adsorb moisture from the air, reducing the risk of water-related damage to the electronic components. Other alternative desiccants with hygroscopic properties include activated alumina, activated carbon, phosphorus-containing compounds, and metal salts. These materials also have the ability to remove moisture and other trace gases from the surrounding air.
The presence of water can impact the effectiveness of solvents, and the hygroscopicity of certain chemicals can result in self-contamination and decreased cleaning efficiency over time. Anhydrous solvents with minimal water content are often preferred to mitigate this issue.