Electronic devices with moisture guiding structures

摘要

Electronic devices may have housings in which components are mounted. Some of the components may be sensitive to moisture. Other components may be insensitive to moisture and may form openings in a device housing that allow moisture to escape from within the housing. Components may be mounted on substrates such as printed circuit board substrates. Moisture repelling layers and moisture attracting layers may be patterned to form channels and other structures that guide moisture away from sensitive components towards insensitive components. Moisture repelling and attracting layers may also be used to limit the lateral spread of a conformal coating layer when coating components.

主权项

1. A housing; a moisture-sensitive component in the housing; and a moisture guiding structure within the housing that is formed from patterned coatings, wherein the patterned coatings comprise a hydrophilic coating layer that attracts moisture and a hydrophobic coating layer that repels moisture, wherein the hydrophilic and hydrophobic coating layers direct moisture away from the moisture-sensitive component, wherein the hydrophilic coating layer comprises a material selected from the group consisting of: metal oxide, material in which metal oxide particles have been incorporated within a binder, polyurethane, and polyethylene oxide, and wherein the hydrophobic coating layer comprises a material selected from the group consisting of: parylene, silicone, and polytetrafluoroethylene.