A new Apple patent application published today by the U.S. Patent & Trademark Office covers hydrophobic conformal coatings and silicon seals for waterproofing iOS devices. According to PatentlyApple, Apple’s invention is about improving moisture resistance of an assembled printed circuit board (PCB), and involves the use of a hydrophobic conformal coating, designed to increase moisture resistance of electrical components.
Apple’s filing details that a method is devised for applying a hydrophobic conformal coating to a PCB, that includes depositing a hydrophobic conformal coating across an exterior surface of the electromagnetic interference (EMI) shield and the PCB by a chemical vapor deposition (CVD) operation. Another method Apple notes is creating a hydrophobic seal around an electrical connector on a PCB, by configuring a silicone seal on the PCB to frame the electrical connector on the PCB such that the silicone seal covers a soldered portion of the electrical connector.
By providing an insulating layer or barrier around these highly susceptible parts, water resistance can be substantially increased without obscuring functional openings leading into a device housing of a particular electronic device. A thin hydrophobic (i.e., water resistant) conformal coating having a thickness between at least one and ten microns can be applied to a substrate using a plasma-assisted chemical vapor deposition (PACVD) process. The PACVD process charges the surface of the substrate so that the coating can be bonded to the charged surface.
As with every patent filing, which method Apple will finally settle on for waterproofing future iDevices is of course unknown at this time.