Parylene Coated Magnets

Accordingly, Parylene coated magnets—primarily using Parylene C—are magnets that have been treated with this coating, offering enhanced protection and durability.

These magnets, which include Neodymium, Samarium Cobalt, and ferrite types, are ideal for sensitive applications such as medical devices and microelectronics.

Magnets are coated with parylene using a chemical vapor deposition (CVD) process, typically at a deposition rate of approximately 0.002 mm per hour. While the required coating thickness can be as thin as 0.005 mm, it is often applied as thick as 0.015 mm for added durability.

The process starts with raw dimer in solid form, which is placed into a loading boat and heated in a vaporizer to temperatures between 100 °C and 150 °C. Under vacuum, the vaporized dimer is drawn into a high-temperature furnace, causing it to sublimate and split into monomer gas. This gas is then directed into a coating chamber, where it uniformly deposits onto the magnets. For small magnets, a barrel method is used, where magnets are slowly tumbled in a rotating barrel within the chamber, ensuring even coverage across all surfaces. The process doesn’t rely on electric charge but purely on surface exposure to the parylene vapor.

• Parylene coating is a low-stress conformal type that makes the magnets free of pinholes, while also being well-suited for micro magnets and special shaped magnets.
• Parylene coating has high electrical resistivity.
• Parylene is hydrophobic, acting as an effective barrier against ionic species like gases and moisture.
• Superior temperature stability is another benefit, with Parylene performing well from -200 to 150 degrees Celsius.
• Excellent chemical resistance to solvents, acids, and alkalis further enhances its durability.
• The vapor deposition process allows for precise control of coating thickness at the micron level.
• With its colorless and highly transparent qualities, Parylene does not alter the original appearance of the product.
• Parylene coating is FDA approved and complies with USP Class VI Plastics requirements, ensuring exceptional biocompatibility. Additionally, it is UL listed, MIL-I-46058C Type XY, and IPC-CC-830 approved, meeting rigorous safety and performance standards.
• Parylene coating may be applied to many materials including magnets in assemblies.
• However, the high cost of precursor materials makes Parylene coating more expensive.
• Lubricating properties of Parylene result in low adhesive bond strength.