Parylene XY is a transparent, thin (hundreds of nanometers to a few micrometers), well adhering, pin-hole and defect free conformal coating. They are coated uniformly on flat surfaces and component configurations with sharp edges, points, flat surfaces, crevices or exposed internal surfaces are coated uniformly without voids.

Parylene Process:

Sensors measure specific aspects of data-driven technology.  Included are such performance properties as acceleration, fluidity, humidity/temperature, position, pressure or vibration.  Sensors collect data  and respond with feedback for a multitude of electronic devices utilizing printed circuit boards (PCBs) and related sensitive electronics.  They have been successfully adapted for use across a wide range of applications, including aerospace/military, appliance, automotive, communications, consumer, industrial, medical and transportation uses.  

PCBs and the larger devices they power often need to function in harsh operating environments.  Conformal coatings -- liquid acrylic, epoxy, silicone and urethane resins, and chemical vapor-deposited (CVD) parylene – provide PCBs and similar electronics excellent barrier, dielectric and insulative protection through most performance conditions, sustaining their expected utility.  Substrate adhesion is necessary to conformal film reliability; coatings do not work if they delaminate or otherwise disengage from the components they are applied to protect. 

 Unlike liquid coatings – acrylic, epoxy, silicone and urethane – parylene (XY) does not use wet method application.  It can neither be brushed or sprayed onto substrate surfaces, nor will immersion – soaking the substrate in a bath of coating material – work.  In addition, XY’s:

The phrase “in-line parylene processing" is deceptive  because it does not accurately describe the method in which parylene (XY) is applied as a conformal coating.  It is true that some aspects of the traditional production line are relevant, but primarily in a fractional way. without the traditional station-to-station regimentation of standard in-line manufacturing processes.

After pertinent research you’ve determined parylene (XY) is the best conformal film for your coating assignment.  Especially relevant were XY’s uniform protective and insulative properties, which are useful for numerous applications, ranging from printed-circuit boards (PCBs) to medical implants to military-grade purposes.  Among parylene’s other advantages are: 

Liquid conformal polymers – resins of acrylic (AR), epoxy (ER), silicone (SR) and urethane (UR) – use wet application processes to attach to substrates.  Most prominent of these are brushing the wet coating onto an assembly, dipping (immersing) the assembly in a bath of liquid coating, or spraying the conformal film onto the designated surface.  The coating materials are wet when they are applied.  If

Parylene conformal coating (XY) provides insulative protection for complex electronic circuit assemblies expected to function through rigorous operating conditions -- potential chemical, electrical, moisture and vapor incursion during performance.   Applied through chemical vapor deposition (CVD), parylene penetrates deep within substrate surfaces, generating a level of assembly security surpassing that offered by liquid coatings such as acrylic, epoxy, silicone and urethane.  Yet, although XY is applied in a vacuum, it’s capacity to provide these extraordinary qualities does not exist in one.  Parylene’s durable protective value depends on film adhesion, a quality subject to persistent, thorough inspection throughout the production process.

Unlike liquid conformal coatings joined to substrate surfaces by wet application methods, polymeric parylene (XY) uses a unique chemical vapor deposition (CVD) process to assure adherence.  There is no intermediate liquid phase.  Rather, cross-link polymerization of powdered raw XY-dimer converts the solid to a vapor at the molecular level, polymerizing XY directly as a transparent film on assembly surfaces.