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Parylene Conformal Coatings

Parylene conformal coating is an ultra-thin film polymer coating that provides a uniform pin-hole-free barrier coating to all shapes, edges, crevices, and recesses with the same thickness without suffering any of the edge effects of conventional coatings.

Parylene coatings are highly lubricious, dry film and environmentally protective conformal coatings applied to metals, elastomers, electronics, glass, ceramics and plastics. Our coating services provide the very best thin film conformal coating protection for critical components in many industries including Medical Device, Aerospace, Defence, Automotive and Electronics.

Parylene Coating – Process Video

Parylene Conformal Coating – Quality and Approvals

• CW Parylene coatings are tested to the relevant ISO10993 and USP Class VI tests.
• Our US FDA MAF#1176 is available to support client company 510k submissions.
• Parylene meets the requirements of IPC-CC-830 and Mil-I-46058C.
• Our coating facilities hold certification to ISO13485, ISO 9001, AS9100, and are ITAR registered where applicable.
• Our coating and masking materials are RoHS and Reach compliant.
• White room and Cleanroom (ISO7) facilities.

ISO 13485:2016

Parylene Conformal Coating – Industries

AEROSPACE AND DEFENCEELASTOMERS
ELECTRONICMEDICAL

Parylene Conformal Coating – Applications

Environmental Protection
Parylene is considered by many to be the very best thin film conformal coating for environmental protection particularly in high reliability applications.
It is the coating of choice to ruggedize critical electronics, devices and subassemblies in industries such as Aerospace, Defence and Medical.
Parylene provides protection from moisture, corrosive bodily fluids, chemicals, gases, temperature and fungus far surpassing the protective properties of most other conformal coatings.

Solves dry friction
Parylene is a highly lubricous dry film coating.
Parylene N has a low co-efficient of friction of 0.25 static and dynamic between 2.5 – 6µm.
Being particulate free and bio compatible, it is the favoured dry film lubricant for release-ability of manufacturing aids for medical device manufacture.
For elastomeric applications Parylene is used to remove tackiness from the substrate at coating thicknesses as low as 1500Ã….

Applications for Parylene coatings

Parylene Coating – Benefits

• Ultra thin lightweight film – coating thickness of less than 1 µm can be applied, penetrating micro porosity to provide pin hole free protection and lubricity.
• Uniform – thickness tolerances are typically held to ±20% from nominal.Tolerances as tight as ±5% are possible even for the most intricate and complex shapes.
• Stability – Parylene is inert and insoluble in most solvent systems within its temperature range. It is thermally stable between -200°C and 125°C and higher in an inert environment.
• Dielectric strength – extremely high dielectric strength of 7 kV/mil.
• Lubricant – Parylene acts as a dry film lubricant, eliminating the need for liquid release agents.
• Environmental barrier protection – Parylene provides protection from moisture, corrosive bodily fluids, chemicals, gases, temperature and fungus.
• Low stress process – applied at room temperature. Any object which can be exposed to medium vacuum can be coated with Parylene.
• Elasticity – elongation to break of Parylene C is 200%.
• Optical clarity – Parylene C is optically clear.
• Sterilisation – by any method has little impact to the physical properties of Parylene.
• FDA – Device and Drug master file held with the FDA to support client company 510k submissions.

Parylene Conformal Coating – Process

• Parylene is applied at room temperature with specialized vacuum deposition equipment that permits control of the coating rate and thickness.
• The deposition process takes place at the molecular level as the chemical, in a dimer form, is first converted into a gas under vacuum and heat; then it is pyrolized to cleave the dimer; and finally the monomer is deposited as a clear polymer film on all exposed surfaces in the deposition chamber.
• The single coating builds up one molecule at a time, encapsulating any and all exposed surfaces. The material is applied at rates of 1 to 2 µm per hour. Coating thicknesses from 0.1 to 76 µm can be applied in a single operation.
• Parylene will conform to any surface that is stable in a vacuum environment, regardless of the complexity of the geometry.
• Parylene is applied in a gaseous state, so there is no risk for bridging, spotting or pooling as can occur with a liquid conformal coating.

Parylene Coating Properties & Variants

While there have been many types of Parylene researched and developed over the past 40 plus years, Parylene N and C have the widest commercial use. Each has its own unique electrical and physical properties.

• Parylene conformal coatings are applied by vapour deposition under a vacuum in a coating chamber at room temperature. The Parylene coating process exposes objects to a gas-phase monomer at low pressure. Through vacuum deposition, Parylene condenses and polymerizes on the object’s surface in a polycrystalline formation. The Parylene coating grows at a rate 0.2µm – 0.3µm per minute depending on type N or C respectively.
• Parylene C is most widely used as it has good electrical and physical properties.
• Parylene N is selected for its high dielectric strength and where greater coating penetration is needed.

Parylene conformal coatings are normally applied using a batch process where parts are put into a chamber, either horizontal (tumbler) or vertical. The batch process offers a cost-effective solution for many applications.

CW Parylene N

Type N or Natural, has the highest dielectric strength of these two commercial versions, and a dielectric constant value independent of frequency. It is able to penetrate crevices more effectively than type C because of the higher level of molecular activity that occurs during deposition. Parylene N is commonly used where lubricity is most needed and for high frequency electrical applications because of its low dissipation and dielectric constant values.

CW Parylene C

Parylene C differs chemically from N, having a chlorine atom on the benzene ring that results in a useful combination of electrical and physical properties including particularly low moisture and gas permeability. Parylene C deposits on substrates at a faster rate than Parylene N, and has a lower throw capability and an associated reduction in crevice penetration activity. Parylene C is commonly used for environmental protection.

Other types of Parylene Coatings

For applications operating continuously in air temperatures greater than 125°C other variants are available. However, the deposition rates for these higher temperature capability variants are significantly slower than those for Parylene N or C and the cost of application will increase proportionally. For the majority of commercial applications, Parylene N or C will be the logical choice. However, in some cases an alternative variant may be more appropriate. We can advise on the best route on specific projects once the end use requirements are assessed.

Parylene Coating – Dimer Supplier

Parylene raw materials are called dimers. CWST offers IPC-CC-830 and USP Class VI approved Parylene dimers. These are the key raw materials used in the Parylene coating process. The most common types of commercial parylene raw material or dimers are Dimer C and Dimer N. Read More >>

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