Polyurethane Rubber Keypad Protective Overcoat: What is It and What does It do?

A Definition of a Polyurethane Rubber Keypad Protective Overcoat
Heap of rubber keypadsPolyurethane is a protective overcoat applied to 100% of a rubber keypad. This clear protectant provides wear resistance for very high use applications and, in some cases, can increase graphics’ abrasion resistance by 20 times. Adding protective coatings like polyurethane to rubber keypads makes them more rugged and prolongs their longevity. By applying a polyurethane protective overcoat to rubber keypads, you protect them from a variety of uses and situations, enhancing their quality and reliability.
Specifically, a polyurethane protective overcoat protects rubber keypads from oils, dirt, and contamination. The polyurethane may be applied in a glossy or matte finish, to meet the aesthetic requirements of the rubber keypad. The polyurethane coating is deposited on the top surface of the keypad, over the printing, and it does not affect or harm the printing in any way. A polyurethane protective overcoat is the protective coating of choice for rubber keypads that call for a higher abrasion or plastic feel, and typical applications include automotive and point of sale handheld devices.
Benefits of a Polyurethane Rubber Keypad Protective Overcoat
Protective keypad coatings, such as a polyurethane overcoat, protect electronic products. These protective overcoats also allow for superb tactile operation and increase a keypad’s lifecycle through enhanced wear resistance. On average, adding a polyurethane overcoat increases the longevity of a rubber keypad by four times. A polyurethane overcoat also protects rubber keypads from dust and from a changed feel after heavy use. Typically, a polyurethane rubber keypad protective overcoat protects keypads from chemicals, moisture, scratches, and other normal wear and tear. Polyurethane overcoats also protect the printed and molded colors on the keypad, plus the printed text on the keys themselves.
Benefits of a polyurethane rubber keypad protective overcoat include:

  • 100% top coating
  • Wear resistant for high-use applications
  • High resistance to wear in normal applications
  • Clear coating
  • Highly flexible to maintain the rubber keypad’s elasticity
  • Good adhesion properties between the top coat and the rubber keypad’s surface
  • Results in an easy to clean surface
  • Abrasion resistant
  • Resistant against organic solvents
  • Offers a substantial performance to cost ratio
  • Provides a moisture-resistant electronic switch solution for both laser-etched rubber keypads and screen-printed rubber keypads

It is important to keep in mind that without applying a polyurethane rubber keypad protective overcoat, the printed text and colors may wear off of the keypad with use and over time. The polyurethane rubber keypad protective overcoat provides a clear, seamless layer over top of the screen printing and keys.
Industries Utilizing Rubber Keypads with Polyurethane Protective Overcoat
Any industry that utilizes rubber keypads in harsh environments or in high usage situations benefits from the protection provided by a polyurethane rubber keypad protective overcoat. Industries that most commonly use rubber keypads with polyurethane protective overcoat include:

  • Military
  • Telecommunications
  • Medical devices
  • Laboratory instrumentation
  • Point of sales
  • Industrial equipment
  • Consumer electronics
  • Automotive
  • Aerospace

Process for Testing Polyurethane Rubber Keypad Protective Overcoat
phone-949084_640The RCA Abrasion Wear Test is the industry standard for testing rubber keypads that have been treated with a polyurethane protective overcoat. RCA abrasion testing gives manufacturers a cost-effective way to evaluate the performance of inks and coatings, such as a polyurethane rubber keypad protective overcoat, on common items. The RCA abrasion testing specification ASTM F2357 requires the use of the RCA Abrasion Wear Tester, manufactured by Norman Tool.
In fact, the RCA Abrasion Wear Tester is widely used by many silicone keypad and membrane switch manufacturers. The abrader also is used in the automotive, appliance, cell phone, plastics, and coating industries. The abrasion test uses an inexpensive, disposable abrasion paper that provides consistent ratings. At the end of the test, an evaluation of the amount of visible wear is performed.

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