Guide to Protective Coatings for Rubber Keypads

A Definition of Rubber Keypad Protective Coatings

Protective keypad coatings are important for many electronic products, as they can enhance the value of the product. The protective keypad coatings also offer superb tactile operation and multiple finishing techniques. Rubber keypad protective coatings help to increase a keypad’s lifecycle by enhancing wear resistance. They also can preserve the product by helping to reduce dust and the chance of the surface feel of the silicone changing after heavy use.

What are Protective Coatings for Rubber Keypads?

Types of Protective Coatings for Rubber Keypads

It is extremely important to apply the correct protective coating to rubber keypads, based on their applications and intended use. Rubber keypad protective coatings include silicone coating, polyurethane, parylene, epoxy, and clear coat, among others.

Silicone Spray – Applied by spray and wear resistant. This coating is typically used for low to medium use applications. Wear resistance is better than that of screen printed coating. In fact, silicon spray overcoat can double the abrasion resistance of printed graphics on rubber keypads.

  • Clear matte protective spray coating offers good wear protection and a smooth, silky finish that helps reduce dirt and dirt attraction.
  • Clear silicon protective spray coating with antibacterial additive offers both wear protection and antibacterial resistance.

Polyurethane – Protective clear coating applied to 100% of the keypad. Wear resistant for very high use applications, and in some cases can increase abrasion resistance of graphics by 20 times.
Parylene – Protective clear coating applied to 100% of the keypad. This coating has high resistance to wear for high use applications. The best coating that is 100% applied to keypads and provides resistance to most chemicals.
Epoxy – Protective clear coating applied to keytops only. 100% wear resistant thick coating for high use applications. These clear epoxy drip coatings on keytops provide a hard plastic feel or lens effect.
Clear Coat – Lowest cost protective coating. This coating typically is applied for low use applications. Resistance increases with each coating.
Potential Health Benefits of Rubber Keypad Protective Coatings bannerspages_main_rubberkeypads
As concerns over illnesses and infections such as the flu and MRSA spread each year, hospitals and other industries look to control those illnesses and infections by adding anti-bacterial materials to the protective coatings on rubber keypads. The anti-bacterial additives used in the material or spray coating are produced by incorporating a silver-based component, since silver is a well-known biocide. When the additive is moistened with normal atmosphere or hand contact, the hydrolytic compound releases silver ions and kills the “microscopic bugs.”
To overcome the challenge of the additive’s expense, companies can incorporate the additive into a compatible polymer in a viscosity appropriate for spraying that can be used to coat the surface of the molding. This provides a lasting anti-bacterial coating as well as serves as a protective coating for any printing that also may have been applied. The surface only needs to be microns thick to have the same efficacy. Since the coating is in a cross-linked polymer that bonds with the bulk molding as a permanent coating, it resists washing off or hand abrasion.
As tests have shown, the anti-bacterial coating starts reducing bacteria immediately and shows significant reductions after just one hour. The coating seems to significantly reduce the spread of infection, cross contamination, and bio-film build up.
Final Thoughts on Protective Coatings for Rubber Keypads
As rubber keypads are produced, adding a protective coating at the end of production ensures the ruggedness and longevity of the keypad. Adding protective coatings to rubber keypads and their graphics is a smart option for protection from a variety of issues and situations. As advancements in coating technology and fluid dynamics have been made, extremely high quality and reliable options for rubber keypad protective coatings have become available.

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