Parylene is a polymeric material that is commonly applied as a conformal coating layer in electronic applications. Parylene conformal coatings are used to provide environmental and/or dielectric isolation. They offer pinhole-free layers with low water permeability, high flexibility and high mechanical strength (see table). While parylene coatings are most frequently applied onto the electronic circuitry and sensors they also have impeccable properties that are beneficial for use in medical substrates.Read More
Parylene Coating Blog by Diamond-MT
Parylene is a chemically inert conformal coating . It has a well-established chemical vapor deposition process and patterning methods. It is a great candidate for use in various application areas (health, aerospace, oil and gas, microelectronics, and so on.) due to its mechanical, physical, optical and chemical properties. Parylene is known to withstand highly corrosive environments and it can be utilized as a barrier material against various etchants in different processes (e.g. Hydrofluoric acid (HF), nitric acid, and acetic acid; potassium hydroxide; and tetramethylammonium hydroxide).Read More
Parylene (XY -- poly(para-xylylene)) organic polymers are highly regarded through a wide range of industries – aerospace/defense, automotive, commercial, industrial, medical – for their utility as conformal coatings. Chemically inert, colorless, linear/polycrystalline and optically clear, XY coatings provide exceptional barrier protection, dielectric reliability, and insulation for printed circuit boards (PCBs) and similar electronic assemblies whose components must maintain performance through all operating conditions. Parylene conformal films safeguard function in the presence of biogases, biofluids, chemicals, moisture/mist, salt compounds, and temperature fluctuations.Read More
Many medical devices rely on sensors to detect and measures conditions affecting patient health. Generally, physical properties within the body – heartbeat, blood pressure, breath rate, temperature, -- are recorded and transmitted to medical personnel/technology, allowing continuous physiological monitoring of health-specific disorders, to improve the quality of diagnosis and treatment.Read More
Operationally, a tube is a hollow cylinder composed of glass, metal, plastic or a similar substance, designed to contain or transport something, typically liquids or gases. When many people think of tubing, they envision its use in construction or mechanics. Tubing of this nature is defined not only by its purpose and the stuff its made of, but also by two dimensions -- outside diameter (OD) and wall thickness (WT).Read More
Conformal coatings are surface treatments applied to a wide range of products and devices used for aerospace, automotive, biomedical, consumer, military and numerous other purposes. Their primary objective is providing a protective film that supports a selected device’s ease of use, operating function, and service life, through an exceptional variety of working environments. Liquid Teflon (PTFE) and parylene are two of the more widely used hydrophobic conformal coatings.Read More
Selection of the material used to coat a medical device is very influenced by the operational environment it will encounter when implanted in the body. Pertinent operational/performance factors typically include:Read More
Biocompatible parylene conformal coatings provide superior protection for medical stents. They represent an enabling technology consistently applied to medical devices of all types for 35 years, to diminish problems stemming from surface microporosity and consequent biofluid corrosion after implant. Providing a reliable barrier to chemicals and moisture, parylene’s static and dynamic coefficients of friction are comparable to those of Teflon.Read More
A metal alloy of nickel (Ni) and titanium (Ti), nitinol (NiTi) exhibits the properties of shape memory and superelasticity, which make it very useful for adaptation to conformal coatings. However, like parylene, nitinol is often difficult and expensive to produce; the extreme reactivity of the alloy’s titanium component requires exceptionally tight compositional control during combination and manufacture.Read More
Application of parylene’s xylylene monomer employs a chemical vapor deposition (CVD) process implemented under a vacuum. Unlike wet coating application methods – brushing, dipping, spraying, etc. – parylene CVD is not line-of-sight. Because the vaporous monomer envelopes all sides of the assembly being coated, appropriate process control allows vacuum deposition of an entirely conformal coating, one that penetrates deep into any crevices, rivulets, or sharp edges and points that exist on the assembly’s surface. The resultant parylene film is insulating, ultra-thin, and pinhole-free, exhibiting superior protective barrier qualities and very low moisture permeability.Read More
Driving development of such emerging areas as microfluidics, advanced bio-sensing, capsule endoscopy, and personalized medicine, microelectromechanical systems (MEMS) are enabling an array of breakthroughs that promise to enhance patient care and outcomes. Protecting sensitive MEMS products from the harsh conditions both inside the body and out is Parylene conformal coating, which is helping to bring these futuristic technologies to fruition.
Parylene conformal coatings are used in many different industries. With their hardness, chemical inertness and ability to perfectly coat any surface, they have expanded well beyond their original military and aerospace applications. Whether it's a protective coating for an LED or a protective shell around a coronary artery stent, the compound is found in places where you might not expect to find it.
Coronary stents are tubular medical implants that serve as a scaffold to open clogged or narrowed arteries in an effort to increase blood flow and reduce the potential for adverse cardiac events such as heart attacks. And providing critical support to these support structures is parylene conformal coating.
Parylene conformal coating boasts a bevy of benefits and properties that make it an appealing choice for a variety of medical device applications. Chief among parylene’s advantages for medical applications, however, is that it meets USP Class VI and ISO 10993 biocompatibility requirements—a characteristic that is essential for many critical medical products and that other types of conformal coating sometimes lack.
A downfall for wet chemistry, liquid coatings such as silicones, acrylics, epoxy, or urethanes is that they do not meet bio-compatibility requirements and cannot be applied with precise control. On the contrary, parylene does not out-gas and is very effective against the passage of contaminants from both the body to substrate or substrate to body.