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Why Parylene?
Parylene is considered by many to be the ultimate conformal coating for the protection of devices,
components and surfaces in the electronics, instrumentation, aerospace, medical and engineering industries.
- Parylene is unique in being created directly on the surface at room temperature.
- There is no liquid phase involved. Coatings are truly conformal, of uniform controllable thickness,
and are completely pinhole-free at thicknesses greater than 0.5μ.
- The coating completely penetrates spaces as narrow 0.01mm.
- No initiators or catalysts are involved in the polymerisation so the coating is very pure
and free from trace ionic impurities.
- Room temperature formation means the coatings are effectively stress-free.
- Any substrate that is vacuum-stable can be coated and the coating adheres strongly to all materials,
even stainless steel, provided the appropriate adhesion-promotion techniques are used.
- Parylenes are chemically and biologically inert and stable and make excellent barrier materials.
- Parylenes are almost completely unaffected by solvents, have low bulk permeability and are hydrophobic.
Coatings easily pass a 100hr salt-spray test.
- Parylenes have excellent electrical properties: low dielectric constant and loss with good high-frequency properties;
good dielectric strength; and high bulk and surface resistivities.
- Parylenes have good thermal endurance: Parylene C performs in air without significant loss of physical properties
for 10 years at 80°C and in the absence of oxygen to temperatures in excess of 200°C.
- Parylenes are transparent and can be used to coat optical elements.
- Coatings perform well as dry lubricants: static and dynamic friction coefficients are equal
and comparable to fluoropolymers with the advantage that they also have good wear and abrasion resistance.
- FDA approval of parylene-coated devices is well-documented. The coatings comply with USP Class VI Plastics
requirements and are MIL-I-46058C / IPC-cc-830B listed (as class XY).
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